title: Tetrahedron

text: A regular tetrahedron can be embedded inside a cube in two ways such that each vertex is a vertex of the cube, and each edge is a diagonal of one of the cube's faces. For one such embedding, the Cartesian coordinates of the vertices are


title: Tetrahedron

text: This yields a tetrahedron with edge-length 2, centered at the origin. For the other tetrahedron (which is dual to the first), reverse all the signs. These two tetrahedra's vertices combined are the vertices of a cube, demonstrating that the regular tetrahedron is the 3-demicube.


title: Tetrahedron

text: The volume of this tetrahedron is one-third the volume of the cube. Combining both tetrahedra gives a regular polyhedral compound called the compound of two tetrahedra or stella octangula.


title: Tetrahedron

text: The interior of the stella octangula is an octahedron, and correspondingly, a regular octahedron is the result of cutting off, from a regular tetrahedron, four regular tetrahedra of half the linear size (i.e., rectifying the tetrahedron).


title: Tetrahedron

text: The above embedding divides the cube into five tetrahedra, one of which is regular. In fact, five is the minimum number of tetrahedra required to compose a cube. To see this, starting from a base tetrahedron with 4 vertices, each added tetrahedra adds at most 1 new vertex, so at least 4 more must be added to make a cube, which has 8 vertices.


title: Tetrahedron

text: Inscribing tetrahedra inside the regular compound of five cubes gives two more regular compounds, containing five and ten tetrahedra.


title: Tetrahedron

text: Regular tetrahedra cannot tessellate space by themselves, although this result seems likely enough that Aristotle claimed it was possible. However, two regular tetrahedra can be combined with an octahedron, giving a rhombohedron that can tile space as the tetrahedral-octahedral honeycomb.


title: Tetrahedron

text: However, several irregular tetrahedra are known, of which copies can tile space, for instance the characteristic orthoscheme of the cube and the disphenoid of the disphenoid tetrahedral honeycomb. The complete list remains an open problem.


title: Tetrahedron

text: If one relaxes the requirement that the tetrahedra be all the same shape, one can tile space using only tetrahedra in many different ways. For example, one can divide an octahedron into four identical tetrahedra and combine them again with two regular ones. (As a side-note: these two kinds of tetrahedron have the same volume.)


title: Tetrahedron

text: A corollary of the usual law of sines is that in a tetrahedron with vertices "O", "A", "B", "C", we have


title: Tetrahedron

text: One may view the two sides of this identity as corresponding to clockwise and counterclockwise orientations of the surface.


title: Tetrahedron

text: Putting any of the four vertices in the role of "O" yields four such identities, but at most three of them are independent: If the "clockwise" sides of three of them are multiplied and the product is inferred to be equal to the product of the "counterclockwise" sides of the same three identities, and then common factors are cancelled from both sides, the result is the fourth identity.


title: Tetrahedron

text: Three angles are the angles of some triangle if and only if their sum is 180° (π radians). What condition on 12 angles is necessary and sufficient for them to be the 12 angles of some tetrahedron? Clearly the sum of the angles of any side of the tetrahedron must be 180°. Since there are four such triangles, there are four such constraints on sums of angles, and the number of degrees of freedom is thereby reduced from 12 to 8. The four relations given by this sine law further reduce the number of degrees of freedom, from 8 down to not 4 but 5, since the fourth constraint is not independent of the first three. Thus the space of all shapes of tetrahedra is 5-dimensional.


title: Tetrahedron

text: Let be the points of a tetrahedron. Let Δ be the area of the face opposite vertex "P" and let "θ" be the dihedral angle between the two faces of the tetrahedron adjacent to the edge "PP".


title: Tetrahedron

text: The law of cosines for this tetrahedron, which relates the areas of the faces of the tetrahedron to the dihedral angles about a vertex, is given by the following relation:


title: Tetrahedron

text: Let "P" be any interior point of a tetrahedron of volume "V" for which the vertices are "A", "B", "C", and "D", and for which the areas of the opposite faces are "F", "F", "F", and "F". Then


title: Tetrahedron

text: For vertices "A", "B", "C", and "D", interior point "P", and feet "J", "K", "L", and "M" of the perpendiculars from "P" to the faces, and suppose the faces have equal areas, then


title: Tetrahedron

text: Denoting the inradius of a tetrahedron as "r" and the inradii of its triangular faces as "r" for "i" = 1, 2, 3, 4, we have


title: Tetrahedron

text: This formula is obtained from dividing the tetrahedron into four tetrahedra whose points are the three points of one of the original faces and the incenter. Since the four subtetrahedra fill the volume, we have formula_33.


title: Tetrahedron

text: Denote the circumradius of a tetrahedron as "R". Let "a", "b", "c" be the lengths of the three edges that meet at a vertex, and "A", "B", "C" the length of the opposite edges. Let "V" be the volume of the tetrahedron. Then


title: Tetrahedron

text: The circumcenter of a tetrahedron can be found as intersection of three bisector planes. A bisector plane is defined as the plane centered on, and orthogonal to an edge of the tetrahedron.


title: Tetrahedron

text: With this definition, the circumcenter of a tetrahedron with vertices ,, can be formulated as matrix-vector product:


title: Tetrahedron

text: Analogously to an obtuse triangle, the circumcenter is outside of the object for an obtuse tetrahedron.


title: Tetrahedron

text: There exist tetrahedra having integer-valued edge lengths, face areas and volume. These are called Heronian tetrahedra. One example has one edge of 896, the opposite edge of 990 and the other four edges of 1073; two faces are isosceles triangles with areas of and the other two are isosceles with areas of , while the volume is .


title: Tetrahedron

text: A tetrahedron can have integer volume and consecutive integers as edges, an example being the one with edges 6, 7, 8, 9, 10, and 11 and volume 48.


title: Tetrahedron

text: A regular tetrahedron can be seen as a degenerate polyhedron, a uniform "digonal antiprism", where base polygons are reduced digons.


title: Tetrahedron

text: A regular tetrahedron can be seen as a degenerate polyhedron, a uniform dual "digonal trapezohedron", containing 6 vertices, in two sets of colinear edges.


title: Tetrahedron

text: A truncation process applied to the tetrahedron produces a series of uniform polyhedra. Truncating edges down to points produces the octahedron as a rectified tetrahedron. The process completes as a birectification, reducing the original faces down to points, and producing the self-dual tetrahedron once again.


title: Tetrahedron

text: This polyhedron is topologically related as a part of sequence of regular polyhedra with Schläfli symbols {3,"n"}, continuing into the hyperbolic plane.


title: Tetrahedron

text: The tetrahedron is topologically related to a series of regular polyhedra and tilings with order-3 vertex figures.


title: Tetrahedron

text: An interesting polyhedron can be constructed from five intersecting tetrahedra. This compound of five tetrahedra has been known for hundreds of years. It comes up regularly in the world of origami. Joining the twenty vertices would form a regular dodecahedron. There are both left-handed and right-handed forms, which are mirror images of each other. Superimposing both forms gives a compound of ten tetrahedra, in which the ten tetrahedra are arranged as five pairs of stellae octangulae. A stella octangula is a compound of two tetrahedra in dual position and its eight vertices define a cube as their convex hull.


title: Tetrahedron

text: The Szilassi polyhedron and the tetrahedron are the only two known polyhedra in which each face shares an edge with each other face. Furthermore, the Császár polyhedron (itself is the dual of Szilassi polyhedron) and the tetrahedron are the only two known polyhedra in which every diagonal lies on the sides.


title: Tetrahedron

text: In numerical analysis, complicated three-dimensional shapes are commonly broken down into, or approximated by, a polygonal mesh of irregular tetrahedra in the process of setting up the equations for finite element analysis especially in the numerical solution of partial differential equations. These methods have wide applications in practical applications in computational fluid dynamics, aerodynamics, electromagnetic fields, civil engineering, chemical engineering, naval architecture and engineering, and related fields.


title: Tetrahedron

text: A tetrahedron having stiff edges is inherently rigid. For this reason it is often used to stiffen frame structures such as spaceframes.


title: Tetrahedron

text: At some airfields, a large frame in the shape of a tetrahedron with two sides covered with a thin material is mounted on a rotating pivot and always points into the wind. It is built big enough to be seen from the air and is sometimes illuminated. Its purpose is to serve as a reference to pilots indicating wind direction.


title: Tetrahedron

text: The tetrahedron shape is seen in nature in covalently bonded molecules. All sp-hybridized atoms are surrounded by atoms (or lone electron pairs) at the four corners of a tetrahedron. For instance in a methane molecule () or an ammonium ion (), four hydrogen atoms surround a central carbon or nitrogen atom with tetrahedral symmetry. For this reason, one of the leading journals in organic chemistry is called "Tetrahedron". The central angle between any two vertices of a perfect tetrahedron is arccos(−), or approximately 109.47°.


title: Tetrahedron

text: Water, , also has a tetrahedral structure, with two hydrogen atoms and two lone pairs of electrons around the central oxygen atoms. Its tetrahedral symmetry is not perfect, however, because the lone pairs repel more than the single O–H bonds.


title: Tetrahedron

text: Quaternary phase diagrams of mixtures of chemical substances are represented graphically as tetrahedra.


title: Tetrahedron

text: However, quaternary phase diagrams in communication engineering are represented graphically on a two-dimensional plane.


title: Tetrahedron

text: If six equal resistors are soldered together to form a tetrahedron, then the resistance measured between any two vertices is half that of one resistor.


title: Tetrahedron

text: Since silicon is the most common semiconductor used in solid-state electronics, and silicon has a valence of four, the tetrahedral shape of the four chemical bonds in silicon is a strong influence on how crystals of silicon form and what shapes they assume.


title: Tetrahedron

text: Tetrahedra are used in color space conversion algorithms specifically for cases in which the luminance axis diagonally segments the color space (e.g. RGB, CMY).


title: Tetrahedron

text: Especially in roleplaying, this solid is known as a 4-sided die, one of the more common polyhedral dice, with the number rolled appearing around the bottom or on the top vertex. Some Rubik's Cube-like puzzles are tetrahedral, such as the Pyraminx and Pyramorphix.


title: Tetrahedron

text: The tetrahedral hypothesis, originally published by William Lowthian Green to explain the formation of the Earth, was popular through the early 20th century.


title: Tetrahedron

text: Stanley Kubrick originally intended the monolith in "" to be a tetrahedron, according to Marvin Minsky, a cognitive scientist and expert on artificial intelligence who advised Kubrick on the HAL 9000 computer and other aspects of the movie. Kubrick scrapped the idea of using the tetrahedron as a visitor who saw footage of it did not recognize what it was and he did not want anything in the movie regular people did not understand.


title: Tetrahedron

text: The skeleton of the tetrahedron (comprising the vertices and edges) forms a graph, with 4 vertices, and 6 edges. It is a special case of the complete graph, K, and wheel graph, W. It is one of 5 Platonic graphs, each a skeleton of its Platonic solid.


title: Made for Love (TV series)

text: Made for Love is an American science fiction black comedy-drama television series based on the 2017 novel of the same name by Alissa Nutting. The series premiered on HBO Max on April 1, 2021. It stars Cristin Milioti, Billy Magnussen and Ray Romano. In June 2021, the series was renewed for a second season which premiered on April 28, 2022. Despite positive response to the series, in June 2022, the series was canceled after two seasons following the merger of HBO Max's parent company WarnerMedia with Discovery, Inc. to become Warner Bros. Discovery. It was removed in December 2022.


title: Made for Love (TV series)

text: After a woman escapes from a suffocating 10-year marriage to a tech billionaire, she discovers her husband had her fitted with a tracking device. The device, which he implanted in her brain, allows him to track her location, watch her live, and know her "emotional data" as she tries to regain her independence.


title: Made for Love (TV series)

text: "Made for Love" is an adaptation of the novel of the same name by Alissa Nutting. WarnerMedia gave the series a greenlight in June 2019 for their streaming service HBO Max. Patrick Somerville was the season one showrunner and writer, with S. J. Clarkson directing. "Made for Love" was the first original series from HBO Max. On June 28, 2021, HBO Max renewed the series for a second season. Executive producers Christina Lee and Nutting were showrunners for season two. The series was canceled after two seasons on June 10, 2022. An official statement on the series cancellation from representatives from HBO Max said:


title: Made for Love (TV series)

text: In July 2019, Cristin Milioti was cast to lead the series. Ray Romano was added in September 2019, with his deal only for one season. Noma Dumezweni would join in October 2019, with Billy Magnussen, Dan Bakkedahl and Augusto Aguilera added in November 2019. In December 2019, Raymond Lee was cast in a recurring role. In July 2021, Caleb Foote was promoted as a series regular for the second season. In November 2021, Sarunas J. Jackson who guest starred on the first season was promoted to a series regular while Chris Diamantopoulos and Angela Lin were cast in recurring roles with Paula Abdul to guest star for the second season.


title: Made for Love (TV series)

text: The series premiered on April 1, 2021 with the first 3 episodes available immediately. The second season premiered on April 28, 2022 with two episodes being released weekly.


title: Made for Love (TV series)

text: For the first season, review aggregator Rotten Tomatoes reported an approval rating of 94% based on 54 critic reviews, with an average rating of 7.20/10. The website's critics consensus reads,""Made for Love" satirical riffs on technology are undeniably clever, but the most valuable special effects in this twisty odyssey are Cristin Milioti's charisma and comedic timing." Metacritic gave the first season a weighted average score of 68 out of 100 based on 18 critic reviews, indicating "generally favorable reviews".


title: Made for Love (TV series)

text: Nina Metz of "Chicago Tribune" rated the series 3.5/4 and found the series "cheekily bewitching, both sardonic and deeply deeply disturbing..." Ben Travers of IndieWire gave the series a B- and said, "Herbert is the proof that "Made for Love" still knows the real deal: that true love can't be quantified, only felt. The more the show lets us feel it, the better off it will be."


title: Y tu mamá también

text: Y tu mamá también (Spanish for "And Your Mother Too") is a 2001 Mexican road film directed by Alfonso Cuarón and co-written by him and his brother Carlos. It stars Mexican actors Diego Luna and Gael García Bernal and Spanish actress Maribel Verdú.


title: Y tu mamá también

text: The film tells a coming-of-age story about two teenage boys who take a road trip with a woman in her late twenties. It is set in 1999 against the backdrop of Mexico's political and economic realities, specifically at the end of the uninterrupted seven decades of presidents from the Institutional Revolutionary Party and the rise of the opposition led by Vicente Fox.


title: Y tu mamá también

text: The film's explicit depiction of sex, nudity, and drug use caused complications in the film's rating. However, in Mexico, the film earned $2.2 million its first weekend in June 2001, setting a new record for the highest box office opening in Mexican cinema. In 2002, the film was released in English-speaking markets under its Spanish title, with a limited release in the United States. The film received critical acclaim and was nominated for Best Original Screenplay at the Academy Awards and as Best Foreign Language Film at the Golden Globe Awards.


title: Y tu mamá también

text: The film opens with "two teenage best friends", working-class Julio and upper-class Tenoch—each having sex with their respective girlfriends before the girls depart on a trip to Italy. Without their girlfriends around, the boys take the opportunity to live as bachelors.


title: Y tu mamá también

text: At a wedding, they meet Luisa, the Spanish wife of Tenoch's cousin, Jano. Trying to impress Luisa, the boys talk about a fictitious, secluded beach called Boca del Cielo ("Heaven's Mouth"); however, she initially declines their invitation to accompany them there. Later, Luisa visits a doctor; after her appointment, she receives a phone call from a drunken Jano, who tearfully confesses that he cheated on her. The next day, Luisa calls Tenoch and asks if their offer to accompany them to the beach is still open.


title: Y tu mamá también

text: Although Julio and Tenoch have little idea where they will actually go, the three set off, driving through rural Mexico. They talk about their relationships and sexual experiences to pass the time: the boys boast about their exploits, while Luisa speaks of Jano and recalls her first love, who died in a motorcycle accident.


title: Y tu mamá también

text: During an overnight stop, Luisa leaves a tearful message on Jano's answering machine explaining that she has left him. Tenoch enters her motel room in search of shampoo but finds her crying. Luisa seduces him, and the two have sex. Julio sees them through the open door and walks away, upset. Afterward, Julio tells Tenoch he had sex with Tenoch's girlfriend. The next day, Luisa notices the tension between the boys, so she has sex with Julio to equalize their perceived status. An upset Tenoch then reveals that he has had sex with Julio's girlfriend. Julio and Tenoch begin fighting, but stop when Luisa threatens to leave them.


title: Y tu mamá también

text: Driving along the coastal road that evening, they chance upon an isolated beach that is actually called Boca del Cielo. Making camp there, they begin to relax and enjoy the ocean, along with the company of a local family. After their campsite is ransacked by a herd of pigs, they spend the night in the nearby village, where Luisa makes another phone call to Jano, bidding him an affectionate but final farewell.


title: Y tu mamá también

text: That evening, Luisa, Julio, and Tenoch get drunk and joke about their sexual transgressions. Julio and Tenoch reveal that they each have frequently had sex with the other's girlfriend. Julio adds that he had sex with Tenoch's mother, but it is unclear whether he is serious. The three dance together sensually and then retire to their room. As Luisa kneels between the boys and stimulates them both, the boys embrace and kiss each other passionately.


title: Y tu mamá también

text: The next morning, the boys wake up together, naked. Tenoch goes outside to vomit, and the boys are eager to return home. The narrator explains that their journey back was quiet and uneventful, and that Luisa stayed behind to explore the nearby coves. The narrator states that the boys' girlfriends broke up with them, and Tenoch and Julio also stopped hanging out.


title: Y tu mamá también

text: A year later, in a chance encounter in Mexico City, Tenoch and Julio have a cup of coffee. They awkwardly catch up on each other's lives and news of their mutual friends. Tenoch informs Julio that Luisa died of cancer a month after their trip, and that she had been aware of her prognosis during the time they had spent together. Tenoch excuses himself because his current girlfriend is waiting for him. Before leaving, Tenoch tells Julio he will see him later; however, the narrator reveals that they will never see each other again.


title: Y tu mamá también

text: Cuarón did not want to cast Luna for the role of Tenoch because he was a teen idol and telenovela star in Mexico. García Bernal convinced Cuarón to hire Luna because their friendship would make the performance of their characters' friendship much easier. Cuarón ultimately hired Luna because he became convinced that their bond would produce a natural and honest performance.


title: Y tu mamá también

text: After working on "Great Expectations" and "A Little Princess", Alfonso Cuarón envisioned a film that was not influenced by production techniques used in Hollywood cinema. Cuarón wanted to reject commercial production techniques he had used in his previous films, like dollies, close-ups, and dissolves. Instead he embraced a documentary-realist style of filmmaking for "Y tu mamá también". Before making the film, Cuarón had worked for some time in Hollywood, prior to return to his roots in Mexican cinema. In an interview, Cuarón said: "I wanted to make the film I was going to make before I went to film school, ...a film in Spanish, and a road movie involving a journey to the beach."


title: Y tu mamá también

text: Additionally, Cuarón has cited "Adieu Philippine", a 1962 French New Wave film, as a crucial inspiration for "Y tu mamá también". Overlaps include a road trip featuring a love triangle, wide shots of a car curving down a road, an omniscient narrator, and a character dancing while staring into the camera.


title: Y tu mamá también

text: In "Y tu mamá también", Alfonso Cuarón reimagined the American road movie genre to depict Mexico's geography, politics, people, and culture. Cuarón wanted to use the road-film genre to challenge mid-20th century Latin-American Cinema movements that rejected the pleasure and entertainment typical of Hollywood commercial cinema created by using fictional characters and story. Cuarón aimed to only borrow the pleasure and entertainment of Hollywood cinema to synthesize with political and cultural exploration of Mexico. Using fictional characters and a story within the documentary-realist style, Cuarón was able to explore Mexico's geographical, cultural, and political landscapes.


title: Y tu mamá también

text: The director and screenwriter were not afraid of developing "Y tu mamá también" during the production process. Cuarón's script was minimal and unelaborate so the actors could contribute to its development during the rehearsal process. Throughout the film the actors improvised. Instead of using high-tech equipment, the entire film was shot with a handheld camera to create a documentary-realist look that mimicked candid footage. In an interview, Cuarón said it all went "back to our original idea of 15 years ago, in which we would do a low-budget road movie that would allow us to go with some young actors and semi-improvise scenes and have a bare storyline but not be afraid of adding things as we went."


title: Y tu mamá también

text: Y tu mama tambien was released on VHS in 2003 by Paramount Home Entertainment, and DVD in 2004 by Metro-Goldwyn-Mayer on MGM DVD, and also on DVD in 2006 by Paramount Home Entertainment and released on Blu-ray in 2012 by Paramount Pictures.


title: Y tu mamá también

text: "Y tu mamá también" was produced by Anhelo Producciones, a company co-founded by Cuarón and Jorge Vergara, a well-known Mexican businessman and the film's producer. The company provided sufficient funding to make the film and launch an impressive marketing campaign. The $5 million film budget was substantial by Mexican film standards. Advertisement and publicity appeared across Mexico. Along with the help of Anhelo Producciones, the ratings board controversy gave the film a lot of free publicity in Mexico. On location production support was provided by Alianza Films International. The film was distributed in Mexico by 20th Century Fox. Shortly after the Mexican release, IFC Films acquired North American distribution rights to the film.


title: Y tu mamá también

text: It was released without a rating in the US because a market-limiting NC-17 was unavoidable. The MPAA's presumed treatment of the film based on the graphic depiction of sex, nudity and drug use in comparison to its much more accepting standards regarding violence, prompted critic Roger Ebert to question why movie industry professionals were not outraged: "Why do serious film people not rise up in rage and tear down the rating system that infantilizes their work?"


title: Y tu mamá también

text: A box office success both domestically and abroad, "Y tu mamá también" grossed $2.2 million in its first week, breaking Mexico's box office records for domestic films. It went on to gross a record $12 million in Mexico.


title: Y tu mamá también

text: The film became a global success after its distribution by U.S. independent companies Good Machine and IFC Films. The film grossed $13.8 million in the US and Canada, making it the second-highest grossing Spanish language film in the United States at the time, and poised Bernal for crossover success into American markets (Bernal's 2004 performance in "The Motorcycle Diaries" would go on to break this record). It grossed $33.6 million worldwide.


title: Y tu mamá también

text: Critically, "Y tu mamá también" garnered acclaim upon its original release. The review aggregator website Rotten Tomatoes reported that 92% of critics gave the film positive reviews, based upon a sample of 139, and an average rating of 8.10/10. The website's critical consensus states, "A road movie that's not only sexy, but intelligent as well". On Metacritic, which assigns a numbered rating out of 100 based on reviews from mainstream critics, the film received an average score of 88 based on 36 reviews, indicating "universal acclaim". Roger Ebert gave the film four stars out of four, saying, "Beneath the carefree road movie that the movie is happy to advertise is a more serious level—and below that, a dead serious level."


title: Y tu mamá también

text: "Y tu mamá también" won the Best Screenplay Award at the Venice Film Festival. It was also a runner up at the National Society of Film Critics Awards for Best Picture and Best Director and earned a nomination for Best Original Screenplay at the 2003 Academy Awards. The film made its US premiere at the Hawaii International Film Festival.


title: Y tu mamá también

text: In 2001, Alfonso and Carlos Cuarón sued the Mexican Directorate of Radio, Television, and Cinema (RTC) for the film's 18+ rating (A grade ‘C’ certificate from the RTC), which they considered illegal political censorship. They took legal action to expose the government-controlled ratings board, prompting its transformation into an autonomous organization free of government involvement and political influence. The 18+ rating was administered for strong sexual content, nudity involving teens, drug use, and explicit language, and prevented audiences under 18 from admittance. They claimed the ratings board was operating illegally by denying parents the responsibility to choose what their child can watch, violating fundamental legal rights in Mexico.


title: Inductor

text: An inductor, also called a coil, choke, or reactor, is a passive two-terminal electrical component that stores energy in a magnetic field when electric current flows through it. An inductor typically consists of an insulated wire wound into a coil.


title: Inductor

text: When the current flowing through the coil changes, the time-varying magnetic field induces an electromotive force ("emf") (voltage) in the conductor, described by Faraday's law of induction. According to Lenz's law, the induced voltage has a polarity (direction) which opposes the change in current that created it. As a result, inductors oppose any changes in current through them.


title: Inductor

text: An inductor is characterized by its inductance, which is the ratio of the voltage to the rate of change of current. In the International System of Units (SI), the unit of inductance is the henry (H) named for 19th century American scientist Joseph Henry. In the measurement of magnetic circuits, it is equivalent to . Inductors have values that typically range from 1µH (10H) to 20H. Many inductors have a magnetic core made of iron or ferrite inside the coil, which serves to increase the magnetic field and thus the inductance. Along with capacitors and resistors, inductors are one of the three passive linear circuit elements that make up electronic circuits. Inductors are widely used in alternating current (AC) electronic equipment, particularly in radio equipment. They are used to block AC while allowing DC to pass; inductors designed for this purpose are called chokes. They are also used in electronic filters to separate signals of different frequencies, and in combination with capacitors to make tuned circuits, used to tune radio and TV receivers.


title: Inductor

text: The term inductor seems to come from Heinrich Daniel Ruhmkorff, who called the famous induction coil he invented in 1851 an inductorium.


title: Inductor

text: An electric current flowing through a conductor generates a magnetic field surrounding it. The magnetic flux linkage formula_1 generated by a given current formula_2 depends on the geometric shape of the circuit. Their ratio defines the inductance formula_3. Thus


title: Inductor

text: The inductance of a circuit depends on the geometry of the current path as well as the magnetic permeability of nearby materials. An inductor is a component consisting of a wire or other conductor shaped to increase the magnetic flux through the circuit, usually in the shape of a coil or helix, with two terminals. Winding the wire into a coil increases the number of times the magnetic flux lines link the circuit, increasing the field and thus the inductance. The more turns, the higher the inductance. The inductance also depends on the shape of the coil, separation of the turns, and many other factors. By adding a "magnetic core" made of a ferromagnetic material like iron inside the coil, the magnetizing field from the coil will induce magnetization in the material, increasing the magnetic flux. The high permeability of a ferromagnetic core can increase the inductance of a coil by a factor of several thousand over what it would be without it.


title: Inductor

text: Any change in the current through an inductor creates a changing flux, inducing a voltage across the inductor. By Faraday's law of induction, the voltage formula_5 induced by any change in magnetic flux through the circuit is given by


title: Inductor

text: So inductance is also a measure of the amount of electromotive force (voltage) generated for a given rate of change of current. For example, an inductor with an inductance of 1 henry produces an EMF of 1 volt when the current through the inductor changes at the rate of 1 ampere per second. This is usually taken to be the constitutive relation (defining equation) of the inductor.


title: Inductor

text: The dual of the inductor is the capacitor, which stores energy in an electric field rather than a magnetic field. Its current–voltage relation is obtained by exchanging current and voltage in the inductor equations and replacing "L" with the capacitance "C".


title: Inductor

text: The polarity (direction) of the induced voltage is given by Lenz's law, which states that the induced voltage will be such as to oppose the change in current. For example, if the current through an inductor is increasing, the induced voltage will be positive at the current's entrance point and negative at the exit point, tending to oppose the additional current. The energy from the external circuit necessary to overcome this potential "hill" is being stored in the magnetic field of the inductor. If the current is decreasing, the induced voltage will be negative at the current's entrance point and positive at the exit point, tending to maintain the current. In this case energy from the magnetic field is being returned to the circuit.


title: Inductor

text: One intuitive explanation as to why a potential difference is induced on a change of current in an inductor goes as follows:


title: Inductor

text: When there is a change in current through an inductor there is a change in the strength of the magnetic field. For example, if the current is increased, the magnetic field increases. This, however, does not come without a price. The magnetic field contains potential energy, and increasing the field strength requires more energy to be stored in the field. This energy comes from the electric current through the inductor. The increase in the magnetic potential energy of the field is provided by a corresponding drop in the electric potential energy of the charges flowing through the windings. This appears as a voltage drop across the windings as long as the current increases. Once the current is no longer increased and is held constant, the energy in the magnetic field is constant and no additional energy must be supplied, so the voltage drop across the windings disappears.


title: Inductor

text: Similarly, if the current through the inductor decreases, the magnetic field strength decreases, and the energy in the magnetic field decreases. This energy is returned to the circuit in the form of an increase in the electrical potential energy of the moving charges, causing a voltage rise across the windings.


title: Inductor

text: The work done per unit charge on the charges passing the inductor is formula_9. The negative sign indicates that the work is done "against" the emf, and is not done "by" the emf. The current formula_2 is the charge per unit time passing through the inductor. Therefore the rate of work formula_11 done by the charges against the emf, that is the rate of change of energy of the current, is given by


title: Inductor

text: In a ferromagnetic core inductor, when the magnetic field approaches the level at which the core saturates, the inductance will begin to change, it will be a function of the current formula_16. Neglecting losses, the energy formula_11 stored by an inductor with a current formula_18 passing through it is equal to the amount of work required to establish the current through the inductor.


title: Inductor

text: formula_19, where formula_20 is the so-called "differential inductance" and is defined as: formula_21.


title: Inductor

text: In an air core inductor or a ferromagnetic core inductor below saturation, the inductance is constant (and equal to the differential inductance), so the stored energy is


title: Inductor

text: For inductors with magnetic cores, the above equation is only valid for linear regions of the magnetic flux, at currents below the saturation level of the inductor, where the inductance is approximately constant. Where this is not the case, the integral form must be used with formula_23 variable.


title: Inductor

text: When a voltage step is applied to an inductor, its short and long-term response are easy to calculate:


title: Inductor

text: Then, if the inductor "L" is connected to a battery of voltage "V" at time "t = 0", the circuit equation for "t > 0" is formula_24, whose solution is formula_25, with limits at "t = 0" and formula_26 as described in the bullets above.


title: Inductor

text: The constitutive equation describes the behavior of an "ideal inductor" with inductance formula_3, and without resistance, capacitance, or energy dissipation. In practice, inductors do not follow this theoretical model; "real inductors" have a measurable resistance due to the resistance of the wire and energy losses in the core, and parasitic capacitance due to electric potentials between turns of the wire.


title: Inductor

text: A real inductor's capacitive reactance rises with frequency, and at a certain frequency, the inductor will behave as a resonant circuit. Above this self-resonant frequency, the capacitive reactance is the dominant part of the inductor's impedance. At higher frequencies, resistive losses in the windings increase due to the skin effect and proximity effect.


title: Inductor

text: Inductors with ferromagnetic cores experience additional energy losses due to hysteresis and eddy currents in the core, which increase with frequency. At high currents, magnetic core inductors also show sudden departure from ideal behavior due to nonlinearity caused by magnetic saturation of the core.


title: Inductor

text: Inductors radiate electromagnetic energy into surrounding space and may absorb electromagnetic emissions from other circuits, resulting in potential electromagnetic interference.


title: Inductor

text: An early solid-state electrical switching and amplifying device called a saturable reactor exploits saturation of the core as a means of stopping the inductive transfer of current via the core.


title: Inductor

text: The winding resistance appears as a resistance in series with the inductor; it is referred to as DCR (DC resistance). This resistance dissipates some of the reactive energy. The quality factor (or "Q") of an inductor is the ratio of its inductive reactance to its resistance at a given frequency, and is a measure of its efficiency. The higher the Q factor of the inductor, the closer it approaches the behavior of an ideal inductor. High Q inductors are used with capacitors to make resonant circuits in radio transmitters and receivers. The higher the Q is, the narrower the bandwidth of the resonant circuit.


title: Inductor

text: where formula_3 is the inductance, formula_30 is the DC resistance, and the product formula_31 is the inductive reactance


title: Inductor

text: "Q" increases linearly with frequency if "L" and "R" are constant. Although they are constant at low frequencies, the parameters vary with frequency. For example, skin effect, proximity effect, and core losses increase "R" with frequency; winding capacitance and variations in permeability with frequency affect "L".


title: Inductor

text: At low frequencies and within limits, increasing the number of turns "N" improves "Q" because "L" varies as "N" while "R" varies linearly with "N". Similarly increasing the radius "r" of an inductor improves (or increases) "Q" because "L" varies with "r" while "R" varies linearly with "r". So high "Q" air core inductors often have large diameters and many turns. Both of those examples assume the diameter of the wire stays the same, so both examples use proportionally more wire. If the total mass of wire is held constant, then there would be no advantage to increasing the number of turns or the radius of the turns because the wire would have to be proportionally thinner.


title: Inductor

text: Using a high permeability ferromagnetic core can greatly increase the inductance for the same amount of copper, so the core can also increase the Q. Cores however also introduce losses that increase with frequency. The core material is chosen for best results for the frequency band. High Q inductors must avoid saturation; one way is by using a (physically larger) air core inductor. At VHF or higher frequencies an air core is likely to be used. A well designed air core inductor may have a Q of several hundred.


title: Inductor

text: Inductors are used extensively in analog circuits and signal processing. Applications range from the use of large inductors in power supplies, which in conjunction with filter capacitors remove ripple which is a multiple of the mains frequency (or the switching frequency for switched-mode power supplies) from the direct current output, to the small inductance of the ferrite bead or torus installed around a cable to prevent radio frequency interference from being transmitted down the wire. Inductors are used as the energy storage device in many switched-mode power supplies to produce DC current. The inductor supplies energy to the circuit to keep current flowing during the "off" switching periods and enables topographies where the output voltage is higher than the input voltage.


title: Inductor

text: A tuned circuit, consisting of an inductor connected to a capacitor, acts as a resonator for oscillating current. Tuned circuits are widely used in radio frequency equipment such as radio transmitters and receivers, as narrow bandpass filters to select a single frequency from a composite signal, and in electronic oscillators to generate sinusoidal signals.


title: Inductor

text: Two (or more) inductors in proximity that have coupled magnetic flux (mutual inductance) form a transformer, which is a fundamental component of every electric utility power grid. The efficiency of a transformer may decrease as the frequency increases due to eddy currents in the core material and skin effect on the windings. The size of the core can be decreased at higher frequencies. For this reason, aircraft use 400 hertz alternating current rather than the usual 50 or 60 hertz, allowing a great saving in weight from the use of smaller transformers. Transformers enable switched-mode power supplies that isolate the output from the input.


title: Inductor

text: Inductors are also employed in electrical transmission systems, where they are used to limit switching currents and fault currents. In this field, they are more commonly referred to as reactors.


title: Inductor

text: Inductors have parasitic effects which cause them to depart from ideal behavior. They create and suffer from electromagnetic interference (EMI). Their physical size prevents them from being integrated on semiconductor chips. So the use of inductors is declining in modern electronic devices, particularly compact portable devices. Real inductors are increasingly being replaced by active circuits such as the gyrator which can synthesize inductance using capacitors.


title: Inductor

text: An inductor usually consists of a coil of conducting material, typically insulated copper wire, wrapped around a core either of plastic (to create an air-core inductor) or of a ferromagnetic (or ferrimagnetic) material; the latter is called an "iron core" inductor. The high permeability of the ferromagnetic core increases the magnetic field and confines it closely to the inductor, thereby increasing the inductance. Low frequency inductors are constructed like transformers, with cores of electrical steel laminated to prevent eddy currents. 'Soft' ferrites are widely used for cores above audio frequencies, since they do not cause the large energy losses at high frequencies that ordinary iron alloys do. Inductors come in many shapes. Some inductors have an adjustable core, which enables changing of the inductance. Inductors used to block very high frequencies are sometimes made by stringing a ferrite bead on a wire.


title: Inductor

text: Small inductors can be etched directly onto a printed circuit board by laying out the trace in a spiral pattern. Some such planar inductors use a planar core. Small value inductors can also be built on integrated circuits using the same processes that are used to make interconnects. Aluminium interconnect is typically used, laid out in a spiral coil pattern. However, the small dimensions limit the inductance, and it is far more common to use a circuit called a "gyrator" that uses a capacitor and active components to behave similarly to an inductor. Regardless of the design, because of the low inductances and low power dissipation on-die inductors allow, they are currently only commercially used for high frequency RF circuits.


title: Inductor

text: Inductors used in power regulation systems, lighting, and other systems that require low-noise operating conditions, are often partially or fully shielded. In telecommunication circuits employing induction coils and repeating transformers shielding of inductors in close proximity reduces circuit cross-talk.


title: Inductor

text: The term "air core coil" describes an inductor that does not use a magnetic core made of a ferromagnetic material. The term refers to coils wound on plastic, ceramic, or other nonmagnetic forms, as well as those that have only air inside the windings. Air core coils have lower inductance than ferromagnetic core coils, but are often used at high frequencies because they are free from energy losses called core losses that occur in ferromagnetic cores, which increase with frequency. A side effect that can occur in air core coils in which the winding is not rigidly supported on a form is 'microphony': mechanical vibration of the windings can cause variations in the inductance.


title: Inductor

text: At high frequencies, particularly radio frequencies (RF), inductors have higher resistance and other losses. In addition to causing power loss, in resonant circuits this can reduce the Q factor of the circuit, broadening the bandwidth. In RF inductors, which are mostly air core types, specialized construction techniques are used to minimize these losses. The losses are due to these effects:


title: Inductor

text: To reduce parasitic capacitance and proximity effect, high Q RF coils are constructed to avoid having many turns lying close together, parallel to one another. The windings of RF coils are often limited to a single layer, and the turns are spaced apart. To reduce resistance due to skin effect, in high-power inductors such as those used in transmitters the windings are sometimes made of a metal strip or tubing which has a larger surface area, and the surface is silver-plated.


title: Inductor

text: Small inductors for low current and low power are made in molded cases resembling resistors. These may be either plain (phenolic) core or ferrite core. An ohmmeter readily distinguishes them from similar-sized resistors by showing the low resistance of the inductor.


title: Inductor

text: Ferromagnetic-core or iron-core inductors use a magnetic core made of a ferromagnetic or ferrimagnetic material such as iron or ferrite to increase the inductance. A magnetic core can increase the inductance of a coil by a factor of several thousand, by increasing the magnetic field due to its higher magnetic permeability. However the magnetic properties of the core material cause several side effects which alter the behavior of the inductor and require special construction:


title: Inductor

text: Low-frequency inductors are often made with laminated cores to prevent eddy currents, using construction similar to transformers. The core is made of stacks of thin steel sheets or laminations oriented parallel to the field, with an insulating coating on the surface. The insulation prevents eddy currents between the sheets, so any remaining currents must be within the cross sectional area of the individual laminations, reducing the area of the loop and thus reducing the energy losses greatly. The laminations are made of low-conductivity silicon steel to further reduce eddy current losses.


title: Inductor

text: For higher frequencies, inductors are made with cores of ferrite. Ferrite is a ceramic ferrimagnetic material that is nonconductive, so eddy currents cannot flow within it. The formulation of ferrite is xxFeO where xx represents various metals. For inductor cores soft ferrites are used, which have low coercivity and thus low hysteresis losses.


title: Inductor

text: Another material is powdered iron cemented with a binder. Medium frequency equipment almost exclusively uses powdered iron cores, and inductors and transformers built for the lower shortwaves are made using either cemented powdered iron or ferrites.


title: Inductor

text: In an inductor wound on a straight rod-shaped core, the magnetic field lines emerging from one end of the core must pass through the air to re-enter the core at the other end. This reduces the field, because much of the magnetic field path is in air rather than the higher permeability core material and is a source of electromagnetic interference. A higher magnetic field and inductance can be achieved by forming the core in a closed magnetic circuit. The magnetic field lines form closed loops within the core without leaving the core material. The shape often used is a toroidal or doughnut-shaped ferrite core. Because of their symmetry, toroidal cores allow a minimum of the magnetic flux to escape outside the core (called "leakage flux"), so they radiate less electromagnetic interference than other shapes. Toroidal core coils are manufactured of various materials, primarily ferrite, powdered iron and laminated cores.


title: Inductor

text: Probably the most common type of variable inductor today is one with a moveable ferrite magnetic core, which can be slid or screwed in or out of the coil. Moving the core farther into the coil increases the permeability, increasing the magnetic field and the inductance. Many inductors used in radio applications (usually less than 100 MHz) use adjustable cores in order to tune such inductors to their desired value, since manufacturing processes have certain tolerances (inaccuracy). Sometimes such cores for frequencies above 100 MHz are made from highly conductive non-magnetic material such as aluminum. They decrease the inductance because the magnetic field must bypass them.


title: Inductor

text: Air core inductors can use sliding contacts or multiple taps to increase or decrease the number of turns included in the circuit, to change the inductance. A type much used in the past but mostly obsolete today has a spring contact that can slide along the bare surface of the windings. The disadvantage of this type is that the contact usually short-circuits one or more turns. These turns act like a single-turn short-circuited transformer secondary winding; the large currents induced in them cause power losses.


title: Inductor

text: A type of continuously variable air core inductor is the "variometer". This consists of two coils with the same number of turns connected in series, one inside the other. The inner coil is mounted on a shaft so its axis can be turned with respect to the outer coil. When the two coils' axes are collinear, with the magnetic fields pointing in the same direction, the fields add and the inductance is maximum. When the inner coil is turned so its axis is at an angle with the outer, the mutual inductance between them is smaller so the total inductance is less. When the inner coil is turned 180° so the coils are collinear with their magnetic fields opposing, the two fields cancel each other and the inductance is very small. This type has the advantage that it is continuously variable over a wide range. It is used in antenna tuners and matching circuits to match low frequency transmitters to their antennas.


title: Inductor

text: Another method to control the inductance without any moving parts requires an additional DC current bias winding which controls the permeability of an easily saturable core material. "See" Magnetic amplifier.


title: Inductor

text: A choke is an inductor designed specifically for blocking high-frequency alternating current (AC) in an electrical circuit, while allowing DC or low-frequency signals to pass. Because the inductor resistricts or "chokes" the changes in current, this type of inductor is called a choke. It usually consists of a coil of insulated wire wound on a magnetic core, although some consist of a donut-shaped "bead" of ferrite material strung on a wire. Like other inductors, chokes resist changes in current passing through them increasingly with frequency. The difference between chokes and other inductors is that chokes do not require the high Q factor construction techniques that are used to reduce the resistance in inductors used in tuned circuits.


title: Inductor

text: The effect of an inductor in a circuit is to oppose changes in current through it by developing a voltage across it proportional to the rate of change of the current. An ideal inductor would offer no resistance to a constant direct current; however, only superconducting inductors have truly zero electrical resistance.


title: Inductor

text: The relationship between the time-varying voltage "v"("t") across an inductor with inductance "L" and the time-varying current "i"("t") passing through it is described by the differential equation:


title: Inductor

text: When there is a sinusoidal alternating current (AC) through an inductor, a sinusoidal voltage is induced. The amplitude of the voltage is proportional to the product of the amplitude (formula_33) of the current and the angular frequency (formula_34) of the current.


title: Inductor

text: In this situation, the phase of the current lags that of the voltage by π/2 (90°). For sinusoids, as the voltage across the inductor goes to its maximum value, the current goes to zero, and as the voltage across the inductor goes to zero, the current through it goes to its maximum value.


title: Inductor

text: If an inductor is connected to a direct current source with value "I" via a resistance "R" (at least the DCR of the inductor), and then the current source is short-circuited, the differential relationship above shows that the current through the inductor will discharge with an exponential decay:


title: Inductor

text: The ratio of the peak voltage to the peak current in an inductor energised from an AC source is called the reactance and is denoted "X".


title: Inductor

text: Reactance is measured in ohms but referred to as "impedance" rather than resistance; energy is stored in the magnetic field as current rises and discharged as current falls. Inductive reactance is proportional to frequency. At low frequency the reactance falls; at DC, the inductor behaves as a short circuit. As frequency increases the reactance increases and at a sufficiently high frequency the reactance approaches that of an open circuit.


title: Inductor

text: In filtering applications, with respect to a particular load impedance, an inductor has a corner frequency defined as:


title: Inductor

text: When using the Laplace transform in circuit analysis, the impedance of an ideal inductor with no initial current is represented in the "s" domain by:


title: Inductor

text: Inductors in a parallel configuration each have the same potential difference (voltage). To find their total equivalent inductance ("L"):


title: Inductor

text: The current through inductors in series stays the same, but the voltage across each inductor can be different. The sum of the potential differences (voltage) is equal to the total voltage. To find their total inductance:


title: Inductor

text: These simple relationships hold true only when there is no mutual coupling of magnetic fields between individual inductors.


title: Inductor

text: Mutual inductance occurs when the magnetic field of an inductor induces a magnetic field in an adjacent inductor. Mutual induction is the basis of transformer construction.


title: Inductor

text: where M is the maximum mutual inductance possible between 2 inductors and L and L are the two inductors.


title: Inductor

text: The table below lists some common simplified formulas for calculating the approximate inductance of several inductor constructions.


title: Acacia

text: Acacia, commonly known as the wattles or acacias, is a large genus of shrubs and trees in the subfamily Mimosoideae of the pea family Fabaceae. Initially, it comprised a group of plant species native to Africa and Australasia. The genus name is New Latin, borrowed from the Greek (), a term used by Dioscorides for a preparation extracted from the leaves and fruit pods of "Vachellia nilotica", the original type of the genus. In his "Pinax" (1623), Gaspard Bauhin mentioned the Greek from Dioscorides as the origin of the Latin name.


title: Acacia

text: In the early 2000s it had become evident that the genus as it stood was not monophyletic and that several divergent lineages needed to be placed in separate genera. It turned out that one lineage comprising over 900 species mainly native to Australia, New Guinea, and Indonesia was not closely related to the much smaller group of African lineage that contained "A. nilotica"—the type species. This meant that the Australasian lineage (by far the most prolific in number of species) would need to be renamed. Botanist Leslie Pedley named this group Racosperma, which received little acclaim in the botanical community.


title: Acacia

text: Australian botanists proposed a less disruptive solution setting a different type species for "Acacia" ("A. penninervis") and allowing this largest number of species to remain in "Acacia", resulting in the two Pan-Tropical lineages being renamed "Vachellia" and "Senegalia", and the two endemic American lineages renamed "Acaciella" and "Mariosousa". Although many botanists still disagreed that this was necessary, this solution was eventually officially adopted at the Melbourne International Botanical Congress in 2011.


title: Acacia

text: A number of species have been introduced to various parts of the world, and two million hectares of commercial plantations have been established. The heterogeneous group varies considerably in habit, from mat-like subshrubs to canopy trees in a forest.


title: Acacia

text: Several species in the genus bear vertically oriented phyllodes, which are green, broadened leaf petioles that function like leaf blades, an adaptation to hot climates and droughts. Some phyllodinous species have a colourful aril on the seed. A few species have cladodes rather than leaves.


title: Acacia

text: The genus was first validly named in 1754 by Philip Miller. In 1913 Nathaniel Lord Britton and Addison Brown selected "Mimosa scorpioides" (≡ "Acacia scorpioides" () = "Acacia nilotica" () ), a species from Africa, as the lectotype of the name. The genus as recognized in 1986 contained 1352 species. That year however, Pedley published a paper in which he questioned the monophyletic nature of the genus, and proposed a split into three genera: "Acacia" sensu stricto (161 species), "Senegalia" (231 species) and "Racosperma" (960 species), the last name first proposed in 1829 by Carl Friedrich Philipp von Martius as the name of a section in "Acacia", but raised to generic rank in 1835. In 2003, Pedley published a paper with 834 new combinations in "Racosperma" for species, most of which were formerly placed in "Acacia". All but 10 of these species are native to Australasia, where it constitutes the largest plant genus.


title: Acacia

text: In 2003, Anthony Orchard and Bruce Maslin filed a proposal to conserve the name "Acacia" with a different type in order to retain the Australasian group of species in the genus "Acacia". Following a controversial decision to choose a new type for "Acacia" in 2005, the Australian component of "Acacia s.l." now retains the name "Acacia". At the 2011 International Botanical Congress held in Melbourne, the decision to use the name "Acacia", rather than the proposed "Racosperma" for this genus, was upheld. Other "Acacia s.l." taxa continue to be called "Acacia" by those who choose to consider the entire group as one genus.


title: Acacia

text: Australian species of the genus "Paraserianthes" "s.l." are deemed its closest relatives, particularly "P. lophantha". The nearest relatives of "Acacia" and "Paraserianthes s.l." in turn include the Australian and South East Asian genera "Archidendron", "Archidendropsis", "Pararchidendron" and "Wallaceodendron", all of the tribe Ingeae.


title: Acacia

text: The origin of "wattle" may be an Old Teutonic word meaning "to weave". From around 700 CE, "" was used in Old English to refer to the interwoven branches and sticks which formed fences, walls and roofs. Since about 1810 it refers to the Australian legumes that provide these branches.


title: Acacia

text: One species of "Acacia" ("sensu stricto") is native to Madagascar, one to Reunion island, 12 to Asia, and the remaining species (over 900) are native to Australasia and the Pacific Islands. These species were all given combinations by Pedley when he erected the genus "Racosperma", hence "Acacia pulchella", for example, became "Racosperma pulchellum".


title: Acacia

text: Acacias in Australia probably evolved their fire resistance about 20 million years ago when fossilised charcoal deposits show a large increase, indicating that fire was a factor even then. With no major mountain ranges or rivers to prevent their spread, the wattles began to spread all over the continent as it dried and fires became more common. They began to form dry, open forests with species of the genera "Allocasuarina", "Eucalyptus" and "Callitris" (cypress-pines).


title: Acacia

text: The southernmost species in the genus are "Acacia dealbata" (silver wattle), "Acacia longifolia" (coast wattle or Sydney golden wattle), "Acacia mearnsii" (black wattle), and "Acacia melanoxylon" (blackwood), reaching 43°30' S in Tasmania, Australia.


title: Acacia

text: An "Acacia"-like long fossil seed pod has been described from the Eocene of the Paris Basin. "Acacia"-like fossil pods under the name "Leguminocarpon" are known from late Oligocene deposits at different sites in Hungary. Seed pod fossils of †"Acacia parschlugiana" and †"Acacia cyclosperma" are known from Tertiary deposits in Switzerland. †"Acacia colchica" has been described from the Miocene of West Georgia. Pliocene fossil pollen of an "Acacia" sp. has been described from West Georgia (including Abkhazia).


title: Acacia

text: Oldest records of fossil "Acacia" pollen in Australia are from the late Oligocene epoch, 25 million years ago.


title: Acacia

text: They are present in all terrestrial habitats, including alpine settings, rainforests, woodlands, grasslands, coastal dunes and deserts. In drier woodlands or forests they are an important component of the understory. Elsewhere they may be dominant, as in the Brigalow Belt, Myall woodlands and the eremaean Mulga woodlands.


title: Acacia

text: In Australia, "Acacia" forest is the second most common forest type after eucalypt forest, covering or 8% of total forest area. "Acacia" is also the nation's largest genus of flowering plants with almost 1,000 species found.


title: Acacia

text: Acacia is a common food source and host plant for butterflies of the genus "Jalmenus." The imperial hairstreak, "Jalmenus evagoras," feeds on at least 25 acacia species. Many reptiles feed on the sap as well, such as the native house gecko in Australia.


title: Acacia

text: Some species of acacia contain psychoactive alkaloids, and some contain potassium fluoroacetate, a rodent poison.


title: Acacia

text: Aboriginal Australians have traditionally harvested the seeds of some species, to be ground into flour and eaten as a paste or baked into a cake. The seeds contain as much as 25% more protein than common cereals, and they store well for long periods due to the hard seed coats. In addition to utilizing the edible seed and gum, the people employed the timber for implements, weapons, fuel and musical instruments. A number of species, most notably "A. mangium" (hickory wattle), "A. mearnsii" (black wattle) and "A. saligna" (coojong), are economically important and are widely planted globally for wood products, tannin, firewood and fodder. "A. melanoxylon" (blackwood) and "A. aneura" (mulga) supply some of the most attractive timbers in the genus. Black wattle bark supported the tanning industries of several countries, and may supply tannins for production of waterproof adhesives.


title: Acacia

text: Wattle bark collected in Australia in the 19th century was exported to Europe where it was used in the tanning process. One ton of wattle or mimosa bark contained about of pure tannin.


title: Acacia

text: In ancient Egypt, an ointment made from the ground leaves of an Acacia (sensu lato) was used to treat hemorrhoids.


title: Acacia

text: The hardened sap of various species of the acacia tree (sensu lato) are known as acacia gum. Acacia gum is used as an emulsifier in food, a binder for watercolour painting, an additive to ceramic glazes, a binding in gum bichromate photography, a protective layer in the lithographic processes and as a binder to bind together fireworks.


title: Acacia

text: "Acacia honey" is not collected from plants in the acacia family, but rather from "Robinia pseudoacacia", known as black locust in North America. Honey collected from "Caragana arborescens" is sometimes also called (yellow) acacia honey. (See also Monofloral honey.)


title: Acacia

text: Some species of acacia – notably "A. baileyana", "A. dealbata" and "A. pravissima" – are cultivated as ornamental garden plants. The 1889 publication "Useful Native Plants of Australia" describes various uses for eating.


title: Acacia

text: Acacia is mentioned in an ancient Egyptian proverb referred to by Amenhotep II: "If you lack a gold battle-axe inlaid with bronze, a heavy club of acacia wood will do."


title: Acacia

text: Acacia (sensu lato) is repeatedly mentioned in the Book of Exodus, perhaps referring to "Vachellia tortilis" (previously known as "Acacia raddiana"), in regards to the construction of the Tabernacle.


title: Doom Patrol

text: Doom Patrol is a superhero team from DC Comics. The original Doom Patrol first appeared in "My Greatest Adventure" #80 (June 1963), and was created by writers Arnold Drake and Bob Haney, along with artist Bruno Premiani. Doom Patrol has appeared in different incarnations in multiple comics, and have been adapted to other media. Although not one of the most popular superhero teams, they have never been out of print for more than a few years since their introduction. The series' creator and fans have suspected that Marvel Comics copied the basic concept to create the X-Men, which debuted a few months later, but other fans also speculate that they share similarities with another Marvel superhero team, the Fantastic Four.


title: Doom Patrol

text: Doom Patrol are a group of super-powered misfits whose "gifts" caused them alienation and trauma. Dubbed the "world's strangest heroes" by editor Murray Boltinoff), the original team included the Chief (Niles Caulder), Robotman (Cliff Steele), Elasti-Girl (Rita Farr), and Negative Man (Larry Trainor); Beast Boy (Garfield Logan) and Mento (Steve Dayton) joined soon after. The team remained the featured characters of "My Greatest Adventure", which was re-titled "Doom Patrol" as of issue #86 (March 1964). The original series was canceled in 1968 when Drake killed the team off in issue #121, last of that series, (September–October 1968). Since then, there have been six "Doom Patrol" series, with Robotman as the only character to appear in all of them.


title: Doom Patrol

text: Doom Patrol first appeared in 1963, when the DC title "My Greatest Adventure", an adventure anthology, was being converted to a superhero format. The task, assigned to writer Arnold Drake, was to create a team that fit both of these formats. With fellow writer Bob Haney and artist Bruno Premiani, he created Doom Patrol, a team of super-powered misfits who were regarded as freaks by the world at large. According to Drake, editor Murray Boltinoff told him "My Greatest Adventure" was in danger of cancellation and he wanted him to create a new feature which might save it. Boltinoff was enthusiastic about Drake's initial pitch with Elasti-Girl and Automaton (changed to Robotman by the team's third appearance, issue #82), but Drake wanted a third character and enlisted Haney's help in coming up with Negative Man. The team was initially announced as "The Legion of the Strange".


title: Doom Patrol

text: Doom Patrol were announced on the cover art of "My Greatest Adventure" #80 (cover dated June 1963). Drake and Haney devised the plot for the issue together, and then each scripted half the issue independently (Drake the first half, Haney the second). Doctor Niles Caulder motivated the original Doom Patrol, bitter from being isolated from the world, to use their powers for the greater good. "My Greatest Adventure" was officially retitled "The Doom Patrol" beginning with issue #86.


title: Doom Patrol

text: The members of the Doom Patrol often quarrelled and suffered personal problems, something that was already common among superhero teams published by Marvel Comics such as Fantastic Four, but was novel among the DC lineup. Doom Patrol's rogues gallery matched the strange, weird tone of the series. Villains included the immortality-seeking General Immortus, the shape-shifting Animal-Vegetable-Mineral Man, and the Brotherhood of Evil led by the Brain, a disembodied brain kept alive by technology. The Brotherhood of Evil also included the intelligent gorilla Monsieur Mallah and Madame Rouge, who was given powers similar to those of Elongated Man, with the extra attribute of a malleable face, allowing her to impersonate various people.


title: Doom Patrol

text: The Doom Patrol had two crossovers: one with the Challengers of the Unknown, teaming up to fight Multi-Man and Multi-Woman; and second with the Flash in "The Brave and the Bold" #65.


title: Doom Patrol

text: As the popularity of the book waned, the publisher cancelled it. Drake killed off the entire Doom Patrol in the final issue, "Doom Patrol" #121 (September–October 1968) where Doom Patrol sacrificed their lives to Madame Rouge and General Zahl to save the small fishing village of Codsville, Maine. This was the first time in comic book history that a cancelled title was concluded with the death of its cast. Artist Bruno Premiani and editor Murray Boltinoff appeared at the beginning and the end of the story, asking fans to write to DC to resurrect Doom Patrol, although the latter was supposed to have been Arnold Drake. According to the writer, he was replaced with the editor because he had just resigned over a pay dispute and moved to Marvel Comics. He finished the script only out of friendship for Boltinoff. A few years later, three more issues appeared, reprints of earlier issues (#89, #95 and #90 appeared as #122, #123 and #124 respectively). A proper "Doom Patrol" revival did not occur until 1977, nine years after the original's demise.


title: Doom Patrol

text: Some similarities exist between the original Doom Patrol and Marvel Comics' original X-Men; Marvel acknowledged the similarity in its humor title "Not Brand Echh". Both include misfit superheroes shunned by society and both are led by men of preternatural intelligence who use wheelchairs. These similarities ultimately led series writer Arnold Drake to argue that the concept of the X-Men must have been based on the Doom Patrol.


title: Doom Patrol

text: In an interview shortly before his death in 2007, Drake took a more moderate position, stating that while it is possible Lee took his ideas from Doom Patrol, he could also have arrived at a similar concept independently: "Since we were working in the same vineyards, and if you do enough of that stuff, sooner or later, you will kind of look like you are imitating each other."


title: Doom Patrol

text: Though the Doom Patrol and the X-Men do share some similarities, there are major differences, such as the Doom Patrol tends to go on bizarre and weird adventures, while the X-Men share their own bizarre adventures they tended to be more focus on the themes of racism, prejudices, and hate crimes. Both have stories that shows them to carry their heroics and are family oriented with internal problems that are disputed or resolved as well as finding common ground with their morals and so forth but while the X-Men still do heroic stories somewhat with certain social political themes, the Doom Patrol was more centered to focus on wacky and bizarre stories more akin to the Fantastic Four.


title: Doom Patrol

text: Writer Paul Kupperberg, a longtime "Doom Patrol" fan, and artist Joe Staton introduced a new team in "Showcase" #94 (August–September 1977). DC was then lining up features for the "Showcase" revival—the series was initially an anthology that would debut new characters who could springboard into their own series if they proved sufficiently popular, and "Showcase" #94 was the first new issue of the series in almost seven years. Editor Paul Levitz instructed Kupperberg and Staton to do a Doom Patrol feature. Kupperberg opted to create a new lineup because he wanted to respect the story in which the Doom Patrol met their deaths, and was inspired by Len Wein and Dave Cockrum's then-recent "all-new, all-different X-Men". Kupperberg has since said he is not proud of the reboot, remarking that "[I was] missing the point of the Doom Patrol. The original group were outsiders and freaks, while my new guys were just comic-book superheroes. I was young and inexperienced and new to writing, with about two years under my belt before getting the gig."


title: Doom Patrol

text: The new team is led by Celsius (Arani Desai), the Chief's previously-unseen wife, who recreates the Doom Patrol to protect herself from General Immortus. Robotman is the only survivor of the original Doom Patrol, and his ruined body is replaced by a new, futuristic one built by Dr. Will Magnus. The Negative Spirit now possesses Russian cosmonaut Valentina Vostok, making her Negative Woman (although its presence does not render her radioactive), and she is able to transform her own body into its form rather than sending it out under control. The final member is Tempest aka Joshua Clay, a Vietnam veteran/deserter who fires energy blasts from his hands.


title: Doom Patrol

text: This new version of the team did not receive its own series following its three-issue tryout. Kupperberg said this was most likely due to poor sales, as even in the months prior to the DC Implosion he heard no word of a new "Doom Patrol" series. However, the team did receive a series of guest appearances in various DC titles, such as "Superman Family" (in a three part arc in the Supergirl feature that was intended for the recently canceled "Super-Team Family"), "DC Comics Presents" (teaming up with Superman in a story which revealed that Vostok's powers had changed to match Larry Trainor's exactly), and "Supergirl". Robotman also appeared as an occasional supporting character in the Marv Wolfman and George Pérez era of "Teen Titans", where it was revealed that Changeling, formerly DP associate Beast Boy, had arranged for Dayton Industries technicians to recreate the Caulder body design for Cliff. His first storyline here had him, the Titans, and a new Brotherhood of Evil battle Madame Rouge and General Zahl, the murderers of the original Doom Patrol, who died in the battle.


title: Doom Patrol

text: Eclipse Comics published "Doom Patrol: The Official Index" with covers drawn by John Byrne in 1984. The two-part series included all of their appearances from "My Greatest Adventure" #80 to their final appearance before their 1980s return.


title: Doom Patrol

text: Kupperberg's enthusiasm for the Doom Patrol remained, and in addition to writing some of the team's post-"Showcase" appearances, he eventually wrote a proposal for a new Doom Patrol series. The proposal was green-lit, and Kupperberg laid the groundwork for the new series by writing the John Byrne-illustrated "Secret Origins Annual" #1, published in 1987, which recapped the origins of the two iterations of the Doom Patrol that had existed thus far. In October 1987, DC relaunched "Doom Patrol", written by Kupperberg and illustrated by Steve Lightle. Lightle took on the assignment with reluctance, having read and disliked Kupperberg's new Doom Patrol in "Showcase" #94–96, and soon quit due to several grievances, such as not being involved in plotting the comic despite the editor repeatedly promising that he would be. He was replaced by a young Erik Larsen after issue #5. Kupperberg later commented, "I like Erik's work, but I don't think he was exactly right for the Doom Patrol. To tell the truth, I don't think either Erik or myself were happy with the arrangement, but we did our best to make it work." For his part, Larsen said he was perfectly happy on the series, in part because on the few occasions where he disliked an aspect of Kupperberg's plots, he would simply revise the plot when he drew the issue. In retrospect, Larsen felt that this practice was overstepping his bounds, but said the editor never objected to it.


title: Doom Patrol

text: This incarnation was a more conventional superhero series than the original volume. It included new members who were hired to the team: the magnetically empowered strong-girl Lodestone (Rhea Jones); Karma (Wayne Hawking), whose psychic power make anyone trying to attack him fall over themselves; and Scorch (Scott Fischer), whose body generates phenomenal quantities of heat focused through his hands, requiring him to wear protective gloves at all times. A DC Comics Bonus Book appeared in issue #9 (June 1988). According to Kupperberg, sales on the series "started out okay, and descended to the point where I was removed from the book and replaced by Grant Morrison in the hopes he could salvage the title."


title: Doom Patrol

text: After the first 18 issues (and various crossovers and annuals), Kupperberg was replaced by Grant Morrison and the comic was no longer submitted to the CCA for approval (relieving the stories and images depicted of several constraints), starting with issue #19. Kupperberg agreed to help Morrison by writing out characters Morrison did not want to use: Celsius and Scott Fischer died before issue #18 - Celsius was killed in an explosion in DC Comics' "Invasion!" event, and Scott Fischer (already suffering from a recurrence of childhood leukemia) was the only known active superhero casualty of the Dominators' gene-bomb (also in "Invasion!"); Karma had left the team as he was still on the run from the law (he became a member of the Suicide Squad and died on his first mission with them in the "War of the Gods" crossover event); the Negative Spirit left Negative Woman's body; and Lodestone plunged into a coma, where she would remain for the first half of Morrison's run on the book. Tempest gave up fieldwork to become the team's physician. Conversely, Morrison picked up a throw-away character from "DP" #14, who was slipped into the art on the last page of #18 to set up Morrison's use: Dorothy Spinner is an ape-faced girl with powerful "imaginary friends." Morrison also substantially retooled Negative Man: Larry Trainor (revealed to be alive in the Kupperburg run, as a prisoner of an underground society but now powerless) is forcibly merged with the Negative Spirit (now a cosmic entity) and a black doctor named Dr. Eleanor Poole, to create a multigender multiracial gestalt entity known as Rebis. The new writer introduced some new characters to the team, including the multiple personality-afflicted Crazy Jane and sentient neighborhood Danny the Street.


title: Doom Patrol

text: Morrison used DC's "Invasion" crossover to restart the book. They incorporated bizarre secret societies, elements of Dada, surrealism, and the cut-up technique pioneered by William S. Burroughs and Brion Gysin. They also borrowed the ideas of Jorge Luis Borges and Heinrich Hoffmann. The original creator, Arnold Drake, said Morrison's was the only subsequent run to reflect the intent of the original series.


title: Doom Patrol

text: Over the course of the series, Morrison dedicated some issues to parody and homage. Willoughby Kipling led the Doom Patrol on a parody of the Brujería story arc of "Swamp Thing: A Murder of Crows" in issues #31–32. Issue #42 featured the origin of Flex Mentallo, who was supposed to be the character in the Charles Atlas ad. A belated lawsuit from the Charles Atlas Company showed that DC was protected under Fair Use doctrine in addition to an expired statute of limitations. Issue #53 featured a dream sequence that mimicked the Stan Lee/Jack Kirby "Fantastic Four", borrowing plot points both from the Galactus Trilogy (FF #48–50) and FF #51, "This Man, This Monster." A 1992 special called "Doom Force" was released as a one-shot and was meant to mimic and parody the "X-Force" book by Rob Liefeld. Issue #45 parodied Marvel's Punisher and Alan Moore in a satire called the Beard Hunter, a perpetually clean-shaven serial killer who murders bearded men and targets the Chief.


title: Doom Patrol

text: Morrison's villains were extremely unusual and strange, even by Doom Patrol's eccentric standards. For example:


title: Doom Patrol

text: In issue #57, it was revealed that the Chief had secretly caused the "accidents" which turned Cliff, Larry Trainor, and Rita Farr into super beings. Chief stated he caused them to gain their powers (or in the case of Robotman, destroyed his original body in order to obtain his brain to put into his robot body) because of his hatred for them. He felt they were spoiled and narcissistic as well as shallow individuals, and that by turning them into "freaks," he could "improve" them as human beings. He further revealed that he lied about not being married to Celsius (the leader of the second Doom Patrol, who Caulder claimed was insane/lying about being married to him) out of anger. He was upset over how the experiments performed on her (like with Elasti-Girl) only gave her super-powers and did not turn her into a freak. When Tempest and Robotman found out his role in "creating" Robotman, Elasti-Girl, and Negative Man, Tempest was killed and Robotman paralyzed. Having been exposed as a villain, Caulder planned to unleash nanobots into the world, hoping to create a catastrophe that would "improve" humanity, regardless of the carnage it would cause. But Caulder's plan was hijacked by the Candlemaker, a violent cosmic horror who is freed by Dorothy in exchange for his resurrection of Tempest (who Candlemaker re-killed). Candlemaker then decapitated Caulder and sought to use the nanobots to enslave humanity. Dorothy, Crazy Jane, and Robotman (freed by the former two) defeated Candlemaker with help from the new reborn version of Rebis. Rebis briefly left the team to mate with a double of himself in order to be "reborn" in a new body as part of a cosmic ritual. However, during the battle, Jane was sent flying into a portal and landed in a world without heroes. Forcibly institutionalized for her mental issues in this new world, the final issue of Morrison's run had Robotman locate Jane as she was about to kill herself and take her to live with Cliff within the confines of Danny the Street.


title: Doom Patrol

text: Morrison left the book with issue #63, and Rachel Pollack took over writing the book the next issue. Pollack's first issue was also the first under the new Vertigo imprint of DC Comics (although the trade paperback editions of Morrison's work do bear the imprint, the original issues did not). Returning characters for Rachel Pollack's run included Cliff Steele, Niles Caulder (kept alive by the nanobots, but reduced to a disembodied head, usually kept on a tray filled with ice), and Dorothy Spinner. Pollack's run had Dorothy as a primary member of the Patrol; she brought her imaginary friends to her aid in combat. Overall, Pollack's run dealt with issues such as the generation gap, humanity, identity, transgender issues, bisexuality, and borrowed elements from Judaism and Kabbalah in the last few issues. The angel Akatriel is used as a major character in the last seven issues.


title: Doom Patrol

text: The first story arc of her run was called "Sliding in the Wreckage". Cliff's computer brain started to malfunction, and he regressed into flashbacks from previous storylines. Dorothy was haunted by African spirits while dealing with living alone in the real world. The Chief was given a new body by Will Magnus, but to atone for his sins, Caulder ripped his head off the body and was kept in cryogenic storage. Meanwhile, the entire Earth had been suffering from random outbreaks of weirdness, contributed by the arrival of something called "The Book of Ice." A government agency known as the Builders, similar to the Men from N.O.W.H.E.R.E., were trying to stop the outbreak, which was apparently linked to a race of shapeshifters known as the Teiresias. As the Chief was kept in a cryogenic state, he appeared in the land of the Teiresias as a face carved in a mountain. They warned him that his arrival in this world was causing the craziness in the real world. Throughout the storyline, little people with backward letters for heads had been seen altering people. These people were apparently older version of nanomachines, referred to as "nannos". At the Doom Patrol headquarters, Builder agents attacked, and in the craziness, two of the Teiresias approached Dorothy with a new brain for Cliff, but to insert it she needed the Chief's expertise. In the Teiresias world, nannos "repaired" the Chief so he could live as a severed head. After his awakening, the craziness seemed to stop, and Dorothy, Cliff, and the Chief each realized that they needed to be together.


title: Doom Patrol

text: The team relocated to Violet Valley's Rainbow Estates, a house haunted by ghosts of those who died in sexual accidents. There, three new members joined. The Bandage People, George and Marion, who were once two workers for the Builders but managed to escape; and the Inner Child, a manifestation of the ghosts' purity and innocence. Another later newcomer of the team was Kate Godwin, aka Coagula, one of the first transgender superheroes. A one-time ally of the team called the Identity Addict, who could become different superheroes by shedding her skin like a lizard, integrated herself back into the team while using the False Memory identity to change the team's memories until she was kicked out by Dorothy.


title: Doom Patrol

text: Villains that the team fought, besides the Builders, included the Fox and the Crow, two animal spirits whose feud Dorothy and Cliff were subsequently pulled into; the Master Cleaner, a being with a human fetus inside a bubble for a head who began "cleaning" the world by stripping it down to nothing and replacing the stolen items, including people, with a paper ticket; and a group of Hassidic healers who called themselves the False Healers and their leader, the Rabbi of Darkness.


title: Doom Patrol

text: Toward the end of the series, Cliff Steele's brain became entirely robotic, until Dorothy Spinner used her imaginary friends to "repair" it. The Chief would later die after trying to enter the Sephirot or Tree of Life.


title: Doom Patrol

text: A new artist, Ted McKeever, took over the artwork for most of the final 13 issues. Pollack continued writing the title until its cancellation with issue #87, in February 1995.


title: Doom Patrol

text: In December 2001, writer John Arcudi and artist Tan Eng Huat launched a new "Doom Patrol" series. This relaunch was not under the Vertigo imprint and returned the title to the mainstream DC universe. The series lasted for 22 issues before it was cancelled.


title: Doom Patrol

text: Arcudi's run largely ignored Morrison and Pollack's runs at first; Arcudi stated in interviews at the time, that the disconnect with the Vertigo run was due to DC editorial having an agreement in play banning writers from using characters and concepts from his run; most notably Rebis/Negative Man and Crazy Jane. However, due to negative fan response to the run; Arcudi was allowed to make reference to the Vertigo series to explain what had happened to the characters from the Pollack run.


title: Doom Patrol

text: The run featured two Doom Patrols: a corporate run Doom Patrol employed by Thayer Jost for Jost Enterprises featuring existing DC characters (Metamophoro, Elongated Man, the second Doctor Light and Beast Boy) and a second "underground" Doom Patrol, run by Robotman and featuring new characters: Fast Forward who could look 60 seconds into the future, Kid Slick who could become entirely frictionless, Fever who could set herself alight, and Freak who possessed mysterious powers from a patristic entity in her soul. The later Doom Patrol were the main characters of the run, with the Jost owned group disbanding when it is revealed by Metamorpho that Robotman had reportedly died four years earlier which results in the 'imposter' Robotman in the team to vanish into nothingness.


title: Doom Patrol

text: The Doom Patrol later rebuild the real Robotman once they recover his head and come to an agreement that Thayer Jost will fund the group so long as Jost has the distributing rights to the Doom Patrol which he uses to create a Doom Patrol TV series based on the Silver Age Team. Over the course of the run Fast Forward loses control of his powers when he tries to look beyond 60 seconds into the future and has to suppress them with medicine in order to function while Kid Slick and Fever start a relationship with one another despite the latter accidentally hospitalising the former with her powers. It is later revealed that part of Robotman's agreement with Jost involves Jost funding for Dorothy Spinner's healthcare as she has been in a coma for the last four years, Cliff deduces that the 'imposter' Robotman was an imaginary Cliff that Dorothy had subconsciously manifested.


title: Doom Patrol

text: Visiting Dorothy, Cliff regained his lost memories and how Dorothy became comatose. Deciding to end the Doom Patrol, Colagula and Cliff took Dorothy to Kentucky to meet her previously unknown birth mother to offer Dorothy a chance at a more 'normal' life, but fearing that Colagula and Cliff were abandoning her, Dorothy had an explosive psychic outburst that reportedly killed Colagula and Cliff, and left her comatose. After finding out that Dorothy was permanently brain dead, Cliff gave the doctors permission to turn off her life support. The death of Dorothy ended Robotman's contract with Jost resulting in Fast Forward, Fever, Kid Slick and Freak being evicted and striking out together with royalty money that Jost gave them from his Doom Patrol TV series, while Cliff set off into the world once again alone.


title: Doom Patrol

text: In August 2004, DC launched a new "Doom Patrol" series after the new team debuted in "JLA". John Byrne wrote and illustrated this series, with inks by Doug Hazlewood. Touted as "Together again for the first time!", Byrne rebooted the series, eliminating all previous Doom Patrol continuity.


title: Doom Patrol

text: The series debuted as part of a six-part storyline that ran in "JLA" #94–99 as "The Tenth Circle", though Byrne only drew this arc as it was written by Chris Claremont.


title: Doom Patrol

text: This reboot was both controversial and short-lived. Besides the removal of the popular Morrison run (and its characters) from canon and the butterfly effect it had on the Teen Titans (which did its best to limit references to Beast Boy's past and avoided using the Brotherhood of Evil until the Byrne run was canceled and Geoff Johns could restore the previous lore),the series garnered controversy over a scene where Robotman and Elasti-Girl are sent back in time and inhabit their younger selves' bodies. During their time in the past, Robotman declares his love for Elasti-Girl. However, due to an age gap between the two heroes, Rita is trapped in her twelve-year-old self's body when the adult Cliff reveals his romantic feelings and kisses her. DC canceled Byrne's series with issue #18. The events in DC's "Infinite Crisis" crossover saw the restoration of the Doom Patrol's full continuity, with the inclusion of all previous incarnations with the reveal that Superboy Prime had "retcon punched" the previous versions of Doom Patrol from existence and for him to "retcon punch" them back into existence after being shot with an arrow that briefly imprisoned Superboy Prime into a rectangular shaped mini-Phantom Zone by Speedy II.


title: Doom Patrol

text: DC editorial used the events of the "Infinite Crisis" storyline to restore the Doom Patrol's continuity. In escaping from the paradise dimension they had inhabited since the end of "Crisis on Infinite Earths", Superboy-Prime and Alex Luthor created temporal ripples which spread throughout reality, causing overlaps on parallel timelines of certain events (Hypertime), such as restoring Jason Todd to life.


title: Doom Patrol

text: In the reprinted edition of "Infinite Crisis", additional scenes added to the collection showed Fever, Kid Slick, Ava, Nudge, Grunt, and Vortex among a two-page spread of heroes.


title: Doom Patrol

text: While assisting the Teen Titans in battling Superboy-Prime, members of the Doom Patrol had flashbacks to their original history. Robotman and Niles Caulder regained memories of the previous Doom Patrol teams with which they had worked. This battle apparently undid some of Superboy-Prime's timeline changes and resulted in a timeline incorporating all previous incarnations of the Doom Patrol, but with Rita Farr and Larry Trainor still alive. The Chief confirmed that Rita was indeed killed by Zahl's explosion. The Chief claimed that he later found her skull and treated it with synthetic proteins until her malleable body was regrown from it.


title: Doom Patrol

text: Steve Dayton is again using the Mento helmet and he is mentally unstable; however, he remembers his time as the Crime Lord. The Chief appears to be manipulating the Doom Patrol members once again; he claims to wish to return them to normal so "maybe one day [they] won't be freaks anymore." After the Doom Patrol encounters the Titans, the Chief tells them that Kid Devil should be a member of the Doom Patrol instead of the Titans, since his unique appearance and nature will always separate him from others. However, Beast Boy, Elasti-Girl, and Mento all stand up to the Chief and force him to step down as the Doom Patrol's leader, with Mento taking over that role.


title: Doom Patrol

text: Two former members of the Teen Titans were dramatically altered during the course of the "Infinite Crisis". Mal Duncan, now code-named Vox, and his wife (Bumblebee) now reside in the Doom Patrol's castle headquarters.


title: Doom Patrol

text: The Doom Patrol later appear in "The Four Horsemen" series (2007), with Caulder back in charge. According to "Titans" (vol. 2) #1, Beast Boy has recently become the team leader.


title: Doom Patrol

text: On February 7, 2009, it was announced at the New York Comic Con that Keith Giffen would be spearheading a revival of Doom Patrol, a title which he has long said he wanted to write. He was joined by artist Matt Clark, who has also long expressed a desire to work on the team. The new series focused on the core members Elasti-Girl, Negative Man, Robotman, and the Chief, while other members such as Mento, Bumblebee, and Vox were to be seen later. The title launched with a 10-page ongoing Metal Men co-feature written by J. M. DeMatteis.


title: Doom Patrol

text: In the first issue, Rita takes on the alias "Elasti-Woman", and according to the team shrink, she's "mothering" Bumblebee, who's now eight inches tall after being shrunk—rather conveniently for her codename—to the size of a bee in "Infinite Crisis".


title: Doom Patrol

text: Nudge, Byrne's addition to the team, was killed in the line of duty and Grunt took off with her corpse.


title: Doom Patrol

text: The current team is working out of Oolong Island (from "52"), which has been turned into a resort town while still maintaining a large super-science background. The Challengers of the Unknown's Rocky Davis is also working closely with the team for spiritual support.


title: Doom Patrol

text: Former member Crazy Jane appears in issue #7. Danny the Street, in a reduced aspect, appears in issue #8.


title: Doom Patrol

text: In September 2011, The New 52 rebooted DC's continuity. In this new timeline, the Doom Patrol is briefly mentioned in issue #24 of Justice League. The team is depicted to be identical in appearance to Paul Kupperberg's 1977 Doom Patrol, consisting of members Celsius, Joshua Clay, and Negative Woman, with additional members Karma and Scott Fischer.


title: Doom Patrol

text: During the "Forever Evil" storyline, Valentina Vostok, Karma, and Scott are killed during a confrontation with Johnny Quick and Atomica of the Crime Syndicate, while Celsius and Joshua Clay are presumably killed. Upon learning of his team's demise, Doctor Niles Caulder sets about assembling a new Doom Patrol.


title: Doom Patrol

text: Following the defeat of the Crime Syndicate, the newly created Doom Patrol is introduced in issue #30 of Justice League. The team includes Robotman, Elasti-Girl, Negative Man and M.I.A. Justice League member Element Woman, whom Caulder refuses to let leave the group and tricks into thinking she was abandoned by the Justice League.


title: Doom Patrol

text: The team attempt to capture Jessica Cruz, the new Power Ring, to force her to join the team. During their attempt to capture her, Caulder demands the team refuse to save civilians in a collapsing building to allow him to lobotomize Cruz and force her to serve him. The Justice League save the people in the building and Lex Luthor manages to hold Caulder back so Batman can convince Cruz to go with the League instead. During their fight, Luthor reveals that Caulder (as he did in the Morrison run) was responsible for causing the "accidents" that gave the Doom Patrol their powers and that both Celsius and Joshua Clay used the chaos of the events of "Forever Evil" to fake their deaths and escape from Caulder. It is also revealed that Caulder poisoned an entire fishing village as part of an experiment, and cured the residents only after Luthor discovered the truth and threatened to expose him.


title: Doom Patrol

text: A new Doom Patrol series written by Gerard Way and drawn by Nick Derington was created as part of the Young Animal imprint. The first issue was published on September 14, 2016. The series has created a multitude of original characters as well as some taken from former team rosters.


title: Doom Patrol

text: Casey Brinke, a fictional character that Danny The Street created in order to communicate with people through comic books, was contacted by Danny when he became threatened by a group of aliens known as Vectra. They wished to profit from his power to create life by turning his fictional people into cheap meat at a fast food restaurant. Danny reached out to Casey, hoping that she could find and join the Doom Patrol after explaining her origin story, both the fictional origin story he had created for her and how she had become a real person.