title: Pathology

text: Although the pathogens and their mechanics differ greatly from those of animals, plants are subject to a wide variety of diseases, including those caused by fungi, oomycetes, bacteria, viruses, viroids, virus-like organisms, phytoplasmas, protozoa, nematodes and parasitic plants. Damage caused by insects, mites, vertebrate, and other small herbivores is not considered a part of the domain of plant pathology. The field is connected to plant disease epidemiology and especially concerned with the horticulture of species that are of high importance to the human diet or other human utility.


title: Vikram (1986 Tamil film)

text: Vikram is a 1986 Indian Tamil-language action thriller film directed by Rajasekhar and stars Kamal Haasan, Sathyaraj, Amjad Khan, Lissy, Dimple Kapadia, Charuhasan and Janagaraj. This is the first Indian film to use computer for recording the songs and was adapted from a novel of same name written by Sujatha. This was Malayalam film actress, Lissy's Tamil film debut who was initially credited as Preethi as well as Hindi film actress, Dimple Kapadia's Tamil film debut. Although the film opened to mixed reviews, it performed very well at the box office and turned out to be a commercially successful venture for Raaj Kamal Films International, crossing 100 days in theatres. A sequel with the same name was released on 3 June 2022, carrying forward the story with Haasan reprising his role of Agent Vikram.


title: Vikram (1986 Tamil film)

text: On 15 March, Ashraf Hussain, Francis Adaikalaraj, RD Bohra are convicted and sentenced to 25 years' imprisonment for their involvement in various anti-national activities. Being unremorseful, the convicts play "Chinese Chequers" while the judge sentences them. Approaching the escort van, one of the convicts boisterously rebukes boasts to the press of becoming free soon. The next day, a nuclear-capable ICBM, Agni Putra, is being dispatched from an unknown location to Satish Dhawan Space Centre, Sriharikota only to be stolen by Sugirtharaja and his henchmen. Back in Headquarters, a visibly distraught panel of ministers and military top brass, led by Mr. Rao, chief of the RAW mulls over the dangerous prospects of the missile falling into terrorists' hands and finally picks the now off-duty agent, Commander Arun Kumar Vikram aka "Vikram" to locate the Agni Putra, with some resentment. The Secretary in the office, Thangaraj, eavesdrop on the mission briefing and passes the information to Sugirtharaja about Vikram, who sends a henchman to kill him. The plan fails as Vikram's three-month-pregnant wife, Ambika, accidentally gets shot by the sniper.


title: Vikram (1986 Tamil film)

text: Enraged, Vikram returns to duty and rebukes Rao for the costly leak and deftly exposes Thangaraj. After torture, Thangaraj names Sugirtharaja as the mastermind in front of the panel, and jumps to his death without giving further details. Desperate to find the missile, which is designed to auto-ignite within 10 days, Rao introduces Vikram to a computer expert Preethi, who knows the design of Agni Putra's on-board computer and its functions. Initially annoyed with Vikram's brutal ways, she mellows down eventually. Sugirtharaja's henchman destroys all the evidence at Thangaraj's home, before Vikram and Preethi arrive. The ensuing chase ends at a cinema theatre, playing a documentary news reel about India-Salamia friendship, where Vikram spots Sugirtharaja. Upon investigation, Vikram realises that the Kingdom of Salamia discourages intel-sharing with India. With the diplomatic route ruled out, Vikram and Preethi, disguising as folk artists, embark along with a troupe to Salamia, ruled by Sultan. Being saved from a snakebite by Vikram, Salamia's princess and Sultan's sister, Inimaasi falls for him. Though Preethi is constantly put off by Vikram's arrogance, she falls for him too.


title: Vikram (1986 Tamil film)

text: Vikram identifies the location of the missile and also discovers that the high priest is a mere puppet under Sugirtharaja's directions, who secretly reprograms the missile, while Preethi is caught by the guards. Preethi, then siding with Sugirtharaja, pretends to be cheated by Vikram and passes information to him, unbeknownst to Sugirtharaja. While trying to reprogram the on-board computer, he loses the information and inadvertently forays into a spa, where he meets Inimaasi. His attempts to expose the priest's treason are met with sheer dissent. The Sultan catches the couple, suspecting fornication, and sentences Vikram to be decapitated in public. Escaping execution, Vikram flees towards the desert, where a gun-toting Sugirtharaja and the Royal Sentries chase him until he gives in to dehydration and is left to die, when he is bitten by a black cobra. Back at the Royal Palace, the high priest stages a coup and holds the Sultan at gunpoint. Meanwhile, Inimaasi manages to escape and finds the delirious Vikram in the desert, and nurses him back. The couple then return to the palace and fight off the armed sentries, while the Sultan impales the high priest.


title: Vikram (1986 Tamil film)

text: Sugirtharaja, oblivious to the fact that Agni Putra's on-board computer has been tweaked, launches it, hoping to decimate New Delhi. At HQ, the Indian officials observe in despair as their computer screen shows a 2D animation of Agni Putra slowly descending upon New Delhi, only for the missile to later drift and plunge into the Bay of Bengal, disarming automatically. Back in Salamia, the royal guards sabotage the siege and restore order. A disillusioned Sugirtharaja forces Preethi into a glider plane and takes off. Vikram manages to board the plane using a lasso through skids. While scuffling, Sugirtharaja sets-off a bomb and jumps with the only parachute backpack available, strapped-on. As the plane explodes, Vikram and Preethi jump-off in a free fall and reach out to Sugirtharaja and grab his parachute, leading to his eventual death, through free fall. Afterwards, Vikram and Preethi get intimate mid-air and as they touch the ground, Inimaasi arrives, calling out to Vikram. Preethi, too, calls him. In a dilemma, Vikram frivolously runs away from both of them.


title: Vikram (1986 Tamil film)

text: Vikram was the second production venture of Kamal Haasan's Raaj Kamal Films International, after "Rajapaarvai".


title: Vikram (1986 Tamil film)

text: On multiple occasions, Kamal Haasan has mentioned that during the story discussion and pre-production of "Vikram", Mani Ratnam was his first choice to direct this film. However, things did not work out due to the fact that Mani was an untested director at that point of time, in terms of big budgeted commercial films. "Vikram" was the first Tamil film to have a budget of over , and features a made-up language spoken in the fictional country Salamia. In the reality television show "Bigg Boss", Haasan revealed that the language was actually created by him. The Salamia scenes were filmed in Rajasthan. Charuhasan's character was inspired by M from the "James Bond" series.


title: Vikram (1986 Tamil film)

text: Vikram was released on 29 May 1986. Upon release, critics drew comparison with the original novel written by Sujatha, and "Vikram" opened to mixed reviews. However, it did very well in the box office, crossing 100 days in several centres in Chennai and Coimbatore.


title: Vikram (1986 Tamil film)

text: According to Haasan, "Vikram" was unfavourably reviewed by film critics, but became a "commercial hit". Made with a budget of 1 crore, the movie eventually collected about 8 crores in box office worldwide. Kamal Haasan donated the proceeds of the film's first show to UNICEF, who were then collecting funds for the welfare of underprivileged children in African continent.


title: Vikram (1986 Tamil film)

text: The soundtrack was composed by Ilaiyaraaja. A total of five songs were composed out of which four were included in the soundtrack. This is the first Indian soundtrack album recorded through computer.


title: Vikram (1986 Tamil film)

text: 36 years later, Kamal Haasan reprised his role of Agent Vikram in the 2022 film of the same name written and directed by Lokesh Kanagaraj (a fan of Kamal Haasan and who was born in 1986).


title: Shemp Howard

text: Samuel Horwitz (March 11, 1895 – November 22, 1955), known professionally as Shemp Howard, was an American actor and comedian. He was called "Shemp" because "Sam" came out that way in his mother's thick Litvak accent.


title: Shemp Howard

text: He is best known as the third Stooge in the Three Stooges, a role he played when the act began in the early 1920s (1923–1932), while it was still associated with Ted Healy and known as "Ted Healy and his Stooges"; and again from 1946 until his death in 1955. During the fourteen years between his times with the Stooges, he had a successful solo career as a film comedian, including series of shorts by himself and with partners. He reluctantly returned to the Stooges as a favor to his brother Moe and friend Larry Fine to replace his brother Curly as the third Stooge after Curly's illness.


title: Shemp Howard

text: Howard was born Samuel Horwitz in Bensonhurst in Brooklyn, NY on March 17, 1895, and raised in Brooklyn. He was the third-born of the five Horwitz brothers born to Lithuanian Jewish parents Solomon Horwitz (1872–1943) and Jennie Horwitz (1870–1939). Irving (1891–1939) and Benjamin (Jack) (1893–1976) were his older brothers; Moses (Moe) (1897–1975) and Jerome (Curly) (1903–1952) were his younger brothers.


title: Shemp Howard

text: Howard's first name, Shmuel (after his grandfather), was anglicized to Samuel, and his parents and brothers usually called him Sam.


title: Shemp Howard

text: Shemp's brother Moe Howard started in show business as a youngster, on stage and in films. Moe and Shemp eventually tried their hands as minstrel-show-style "blackface" comedians with an act they called "Howard and HowardA Study in Black". At the same time, they worked for a rival vaudeville circuit, without makeup.


title: Shemp Howard

text: By 1922, Moe had teamed up with boyhood-friend-turned-vaudeville star Ted Healy in a "roughhouse" act. One day Moe spotted his brother Shemp in the audience and yelled at him from the stage. Quick-witted Shemp yelled right back, and walked up onto the stage. From then on he was part of the act, usually known as "Ted Healy and His Stooges". The Howard brothers were the original Stooges; Larry Fine joined them in 1928. On stage, Healy sang and told jokes while his three noisy stooges got in his way, and Healy retaliated with physical and verbal abuse. Shemp played a bumbling fireman in the Stooges' first film, "Soup to Nuts" (1930), the only film where he played one of Healy's gang.


title: Shemp Howard

text: After a disagreement with Healy in August 1930, Moe, Larry and Shemp left to launch their own act, "Howard, Fine & Howard," and joined the RKO vaudeville circuit. They premiered at Los Angeles's Paramount Theatre on August 28, 1930. In 1931 they added "Three Lost Soles" to the act's name, and took on Jack Walsh as their straight man. Moe, Larry and Shemp continued until July 1932, when Ted Healy approached them to team up again for the Shuberts's Broadway revue "Passing Show of 1932," and they readily accepted the offer. In spite of their past differences, Moe knew an association with the nationally known Healy would provide opportunities the three comics were not getting on their own.


title: Shemp Howard

text: On August 16, 1932, in a contract dispute, Healy walked out of the Shuberts's revue during rehearsals. Three days later, tired of what he considered Healy's domineering handling of the Stooges' career, Shemp left Healy's act to remain with "Passing Show", which closed in September during roadshow performances and after pan reviews in Detroit and Cincinnati. Shemp regrouped to form his own act and played on the road for a few months. He landed at Brooklyn's Vitaphone Studios for movie appearance opportunities in May 1933. When he split from Healy, Shemp was immediately replaced by his and Moe's younger brother Jerry Howard (known as Curly).


title: Shemp Howard

text: Shemp Howard, like many New York-based performers, found work at the Vitaphone studio in Brooklyn. Originally playing bit roles in Vitaphone's Roscoe Arbuckle comedies, showing off his comical appearance, he was given speaking roles and supporting parts almost immediately. He was featured with Vitaphone comics Jack Haley, Ben Blue and Gus Shy, then co-starred with Harry Gribbon, Daphne Pollard, and Johnnie Berkes, and finally starred in his own two-reel comedies. A Gribbon-Howard short, "Art Trouble" (1934), also features then-unknown James Stewart in his first film role. The independently produced "Convention Girl" (1935) featured Shemp in a very rare straight role as a blackmailer and would-be murderer.


title: Shemp Howard

text: Shemp seldom stuck to the script. He livened up scenes with ad-libbed dialogue and wisecracks, which became his trademark. In late 1935, Vitaphone was licensed to produce short comedies based on the "Joe Palooka" comic strip. Shemp was cast as "Knobby Walsh," and though only a supporting character, he became the comic focus of the series, with Johnnie Berkes and Lee Weber as his foils. He co-starred in the first seven shorts, released in 1936–1937. Nine of them were produced, the last two done after Shemp's departure from Vitaphone.


title: Shemp Howard

text: Away from Vitaphone, Howard unsuccessfully attempted to lead his own group of "stooges" in the Van Beuren musical comedy short "The Knife of the Party". It was a rare failure in an otherwise successful solo career. In 1937 he followed his brothers' lead, moved to the West Coast, and landed supporting-actor roles at several studios, predominantly Columbia Pictures and Universal. He worked exclusively at Universal from August 1940 to August 1943, performing with such comics as W. C. Fields (playing Fields' bartender in the film "The Bank Dick", 1940); and with comedy duos Abbott and Costello and Olsen and Johnson. He lent comic relief to Charlie Chan and The Thin Man murder mysteries. He appeared in several Universal B-musicals of the early 1940s, including "Private Buckaroo" (1942; in which he clowned onstage with The Andrews Sisters during their performance of "Don't Sit Under the Apple Tree"), "Strictly in the Groove" (1942), "How's About It?" (1943), "Moonlight and Cactus" (1944) and "San Antonio Rose" (1941), in the latter of which he was paired with Lon Chaney, Jr. as a faux Abbott and Costello. Most of these projects took advantage of his improvisational skills. When Broadway comedian Frank Fay walked out on a series of feature films teaming him with Billy Gilbert, Gilbert called on his closest friend, Shemp Howard, to replace him in three B-comedy features for Monogram Pictures, filmed in 1944–45. He also played a few serious parts, such as his supporting role in "Pittsburgh" (1942) starring Marlene Dietrich and John Wayne.


title: Shemp Howard

text: During 1938–1940 and 1944–1946, Howard appeared in Columbia's two-reel comedies, co-starring with Columbia regulars Andy Clyde, The Glove Slingers, El Brendel, and Tom Kennedy. He was given his own starring series in 1944. He was working for Columbia in this capacity when his brother Curly was felled by a debilitating stroke on May 6, 1946. Curly had already suffered a series of strokes prior to the filming of "If a Body Meets a Body" (1945), and in January 1945 Shemp filled in for Curly at a week-long appearance at the St. Charles Theatre in New Orleans.


title: Shemp Howard

text: Shemp agreed to fill in for Curly in Columbia's popular Stooge shorts, knowing that if he refused, Moe and Larry would be out of work. He intended to stay only until Curly recovered, which never happened as Curly's health continued to worsen. Curly died on January 18, 1952, at the age of 48. Shemp agreed to remain with the group permanently.


title: Shemp Howard

text: Shemp's role as the third Stooge was much different from Curly's. While he could still roll with the punches in response to Moe's slapstick abuse, he was more of a laid-back dimwit as opposed to Curly's energetic man-child persona. And unlike Curly, who had many distinct mannerisms, Shemp's most notable characteristic as a Stooge was a high-pitched "bee-bee-bee-bee-bee-bee!" sound, a sort of soft screech done by inhaling. It was a multipurpose effect: He emitted this sound when scared, sleeping (done as a form of snoring), overtly happy, or dazed. It became his trademark sound as the "nyuk nyuk" sound had become Curly's. Because of his established solo career, he was also given opportunities in the films to do some of his own comic routines.


title: Shemp Howard

text: During this period, The Three Stooges ventured into live television appearances, beginning on Tuesday, October 19, 1948, with Milton Berle on his Texaco Star Theatre program.


title: Shemp Howard

text: Shemp appeared with Moe and Larry in 73 short subjects (77 when counting four that were made after Shemp's death by incorporating stock footage). The trio also made the feature film "Gold Raiders" (1951). Shemp suffered a mild stroke in November 1952, but recovered within weeks. The medical episode had no noticeable effect on his remaining films with the Stooges, many of which were remakes of earlier films that also used recycled footage to reduce costs.


title: Shemp Howard

text: In September 1925, Shemp married Gertrude Frank (1905–1982), a fellow New Yorker. They had one child, Morton (1927–1972). Gertrude Frank Howard outlived her husband and son, and was living when her first cousin Barney Frank (born 1940, the son of her father's brother) became a US Congressman.


title: Shemp Howard

text: Shemp used his somewhat homely appearance for comic effect, often mugging grotesquely or allowing his hair to fall in disarray. He even played along with a publicity stunt that named him "The Ugliest Man in Hollywood". ("I'm hideous," he explained to reporters.) Notoriously phobic, his fears included airplanes, automobiles, dogs, and water. According to Moe's autobiography, Shemp was involved in a driving accident as a teenager and never obtained a driver's license.


title: Shemp Howard

text: On November 22, 1955, Shemp went out with associates Al Winston and Bobby Silverman to a boxing match (one of Shemp's favorite pastimes) at the Hollywood Legion Stadium at North El Centro and Selma Avenues, one block above the Hollywood Palladium. While returning home in a taxi that evening, Shemp died of a massive heart attack, at the age of 60.


title: Shemp Howard

text: Moe's autobiography gives a death date of November 23, 1955, as do most subsequent accounts, because of Moe's book. But much of that book was finished posthumously by his daughter and son-in-law, and some details were confused. The Los Angeles County Coroner's death certificate states that Shemp Howard died on Tuesday, November 22, 1955, at 11:35 [PM] PST. Howard's obituary also appeared in the November 23 afternoon editions of Los Angeles newspapers, citing the death on the night of November 22. A different account is offered by his daughter-in-law Geri Greenbaum, wife of his son, who says Howard's death happened just as their taxi came over the rise on Barham Boulevard, heading to Howard's Toluca Lake home.


title: Shemp Howard

text: Shemp Howard was interred in a crypt in the Indoor Mausoleum at the Home of Peace Cemetery in East Los Angeles. His younger brother Curly is also interred there, in an outdoor tomb in the Western Jewish Institute section, as well as his parents Solomon and Jennie Horwitz and older brother Benjamin "Jack".


title: Shemp Howard

text: The Three Stooges earned a star on the Hollywood Walk of Fame at 1560 Vine Street on August 30, 1983.


title: Shemp Howard

text: Columbia had promised exhibitors eight Three Stooges comedies for 1956, but only four were completed at the time of Shemp Howard's death. To fulfill the contract, producer Jules White manufactured four more shorts by reusing old footage of Howard and filming new connecting scenes with a double, longtime Stooge supporting actor, Joe Palma, who is seen mostly from the back.


title: Shemp Howard

text: Palma came to be known by Stooge fans as the "Fake Shemp". Later, director Sam Raimi and his childhood friend actor Bruce Campbell referred to anyone playing body doubles or stand-ins in other films as "Shemp" or "a Fake Shemp", in reference to these postmortem Stooge scenes.


title: Shemp Howard

text: The re-edited films range from clever to blatantly patchy, and are often dismissed as second-rate. "Rumpus in the Harem" borrows from "Malice in the Palace", "Hot Stuff" from "Fuelin' Around", and "Commotion on the Ocean" from "Dunked in the Deep" (all originals released 1949; all re-edits released 1956). The best-received and most technically accomplished is "Scheming Schemers" (again 1956), combining new footage with recycled clips from "three" old Stooge shorts: "A Plumbing We Will Go" (1940), "Half-Wits Holiday" (1947) and "Vagabond Loafers" (1949).


title: Shemp Howard

text: When it was time to renew the Stooges's contract, Columbia hired comedian Joe Besser to replace Shemp. Columbia discontinued filming new Stooge short subject comedies in December 1957, releasing the last new short in June 1959, but kept the series going into the 1960s by reissuing Shemp's Stooge shorts to theaters. This, as well as a TV release of Stooge shorts, allowed Shemp Howard to remain a popular star for long after he died.


title: Shemp Howard

text: In the television biopic film "The Three Stooges" (2000), Shemp Howard was portrayed by John Kassir, who donned a floppy, straight-haired wig.


title: Miss Kobayashi's Dragon Maid

text: , also known as The Maid Dragon of Kobayashi-san is a Japanese manga series written and illustrated by Coolkyousinnjya. The series began serialization in Futabasha's "Monthly Action" magazine since May 2013 and is licensed in North America by Seven Seas Entertainment. Four spin-off manga have also been serialized in "Monthly Action".


title: Miss Kobayashi's Dragon Maid

text: An anime television series adaptation by Kyoto Animation aired in Japan between January and April 2017. A second season titled "Miss Kobayashi's Dragon Maid S" aired between July and September 2021. A video game titled "Miss Kobayashi's Dragon Maid: Sakuretsu!! Chorogon Breath" was released in Japan in March 2022 and was released in North America by Aksys Games in August 2022.


title: Miss Kobayashi's Dragon Maid

text: As office worker and programmer Kobayashi gets ready for work, she is greeted by a large dragon right outside her front door. The dragon immediately transforms into a human girl in a maid outfit, and introduces herself as Tohru. It turns out, that during a drunken excursion into the mountains the night before, Kobayashi had encountered the dragon, who claimed to have come from another world. Subsequently, Kobayashi had removed a holy sword from Tohru's back, earning her gratitude. With Tohru having no place to stay, Kobayashi offers to let the dragon stay at her home and become her personal maid, to which she agrees, having fallen in love with Kobayashi.


title: Miss Kobayashi's Dragon Maid

text: Despite being efficient at housework, Tohru proves an unorthodox character, occasionally scaring Kobayashi and often bringing more trouble to Kobayashi's life than help. Additionally, Tohru's presence alone attracts other dragons, gods, and mythical beings to her new home. One of these dragons, Kanna, shows up at Kobayashi's door, demanding that Kobayashi return Tohru to the other world. It is then revealed that she'd been exiled from the other world, and having nowhere else to stay, Kobayashi takes her in and becomes her guardian. As both Tohru and Kanna settle into the human world, Kobayashi starts to think of them as family.


title: Miss Kobayashi's Dragon Maid

text: Coolkyousinnjya began publishing the series in the first issue of Futabasha's "Monthly Action" magazine on 25 May 2013. Seven Seas Entertainment licensed the series in North America, and they released the first volume in October 2016.


title: Miss Kobayashi's Dragon Maid

text: A spin-off manga illustrated by Mitsuhiro Kimura, titled , began serialization in "Monthly Action" on 24 December 2016. Seven Seas Entertainment also licensed the spin-off in North America.


title: Miss Kobayashi's Dragon Maid

text: A second spin-off drawn by Ayami Kazama, titled , began serialization in "Monthly Action" on 25 August 2017. The second spin-off is also licensed by Seven Seas.


title: Miss Kobayashi's Dragon Maid

text: A fourth spin-off series drawn by Nobuyoshi Zamurai began serialization in "Monthly Action" on 25 November 2020. The fourth spin-off is also licensed by Seven Seas.


title: Miss Kobayashi's Dragon Maid

text: On 18 April 2016, the wraparound cover of the fourth volume of the series revealed that an anime television series adaptation had been greenlit. The series was directed by Yasuhiro Takemoto at Kyoto Animation and aired in Japan between 12 January and 6 April 2017. Yuka Yamada handled series composition, Miku Kadowaki designed the characters, Nobuaki Maruki served as chief animation director, and the music was composed by Masumi Itō. Crunchyroll simulcast the series outside of Asia as it aired while Funimation released an English dubbed version from 1 February 2017. Plus Media Networks Asia licensed the first season in Southeast Asia and simulcasted it on Aniplus Asia. An original video animation episode was released on the seventh Blu-ray/DVD compilation volume on 20 September 2017. The opening theme is by Fhána, and the ending theme is by Yūki Kuwahara, Maria Naganawa, Minami Takahashi, and Yūki Takada. Madman Entertainment will import Funimation's release into Australia and New Zealand.


title: Miss Kobayashi's Dragon Maid

text: A second season was announced with the release of the eighth manga volume on 12 February 2019. Its status was unknown for a time following the death of Takemoto in the Kyoto Animation arson attack. Titled , the season aired between 8 July and 23 September 2021. Kyoto Animation returned to produce the season. Tatsuya Ishihara replaced Takemoto as director, although Takemoto is credited as "series director" under Ishihara. Yuka Yamada returned to supervise the series' scripts, Masumi Itō returned as music composer, and Miku Kadowaki and Nobuaki Maruki returned as character designer and chief animation director, respectively. The cast members also returned to reprise their roles. An original video animation was released with the special "Volume S" Blu-ray/DVD volume on 19 January 2022. The opening theme is by Fhána, and the ending theme for the first 11 episodes is "Maid With Dragons" by Super Chorogons. In the season finale, "Aozora no Rhapsody" plays as an ending theme, with the song also making a short appearance in episode 3. Bilibili licensed the second season in Southeast Asia.


title: Miss Kobayashi's Dragon Maid

text: On 23 September 2021, Bushiroad announced that Kaminari Games is developing a shoot 'em up video game based on the series. Titled "Miss Kobayashi's Dragon Maid: Burst Forth!! Choro-gon Breath", it was released on 24 March 2022 on Nintendo Switch and PlayStation 4 in Japan, which was followed by a worldwide launch on the same consoles on 25 August 2022.


title: Amy Pascal

text: Amy Beth Pascal (born March 25, 1958) is an American film producer and business executive. She served as the Chairperson of the Motion Pictures Group of Sony Pictures Entertainment (SPE) and Co-Chairperson of SPE, including Sony Pictures Television, from 2006 until 2015. She has overseen the production and distribution of many films and television programs, and was co-chairperson during the late-2014 Sony Pictures hack. The leak uncovered multiple emails from Pascal which were deemed racially insensitive. She left Sony and Pascal later admitted that she was fired from the company.


title: Amy Pascal

text: She rebounded starting her own production comapny, Pascal Pictures, which made its debut with the 2016 "Ghostbusters" reboot. In 2017, she produced "", "Molly's Game" and "The Post". She has received two Academy Award for Best Picture nominations, for producing "The Post" and "Little Women".


title: Amy Pascal

text: Pascal was born on March 25, 1958, in Los Angeles, California. Her father, Anthony H. Pascal, was an economic researcher at the RAND Corporation who wrote about African American social inequality and the cost of AIDS. Her mother, Barbara Pascal, was a librarian and owner of an art bookstore, Artworks. Her family is Jewish. Pascal attended Crossroads School in Santa Monica, then worked as a bookkeeper at Crossroads School while getting her international relations degree at UCLA.


title: Amy Pascal

text: Pascal started her career as a secretary working for producer Tony Garnett at the independent production company Kestrel Films. From 1986 to 1987, she served as Vice President of Production at 20th Century Fox.


title: Amy Pascal

text: Pascal joined Columbia Pictures in 1988, where she was responsible for the development of films including: "Groundhog Day", "Little Women", "Awakenings", and "A League of Their Own". She left Columbia in 1994 and served for two years as the President of Production for Turner Pictures while Scott Sassa was president of Turner Entertainment. During her time at Turner, Pascal hired Damon Lee as a development director.


title: Amy Pascal

text: Pascal rejoined Columbia in 1996 as the studio's president after Turner Pictures merged with Warner Bros. In 1999, Pascal became Chair of Columbia Pictures.


title: Amy Pascal

text: Pascal was named Co-Chairperson of Sony Pictures Entertainment in September 2006. She also served as Chairman of SPE's Motion Picture Group from December 2003 to February 2015. Pascal and SPE's Chairman and CEO Michael Lynton led all of SPE's lines of business, including: motion picture production, acquisition and distribution; television production, acquisition and distribution; television networks; digital content creation and distribution; operation of studio facilities; and development of new entertainment products, services and technologies.


title: Amy Pascal

text: Pascal has overseen the production and distribution of many films, including the "Spider-Man" franchise; the James Bond films "Casino Royale", "Quantum of Solace" and "Skyfall", the first Bond film to gross over $1 billion at the worldwide box office; "The Da Vinci Code" and "Angels & Demons"; Sony Pictures Animation's "The Smurfs", "Cloudy with a Chance of Meatballs", and "Hotel Transylvania"; and Best Picture Oscar nominees "American Hustle", "Captain Phillips", "Zero Dark Thirty", "Moneyball" and "The Social Network".


title: Amy Pascal

text: Pascal, along with Lynton, also oversaw Sony Pictures Television (SPT), which produces and distributes television programming for multiple platforms in the U.S. and internationally.


title: Amy Pascal

text: In 2013, Pascal was elected to the Board of Governors of the Academy of Motion Picture Arts and Sciences.


title: Amy Pascal

text: She clashed with investor Daniel S. Loeb, who accused both Pascal and Lynton of "poor financial controls." According to the "Financial Times", "she employed an assistant who earned more than $250,000 a year, and had use of a private jet and other perks in keeping with Hollywood's golden era rather than an age of austerity." At the end of 2014, Pascal was the only woman at Sony to earn over $1 million per annum, having earned US$3 million a year.


title: Amy Pascal

text: Pascal's contract with Sony was scheduled to expire in March 2015. On February 5, 2015, Pascal announced she would step down in May 2015 Pascal stated during a "Women in the World" discussion on February 11, 2015, that she had been "fired" by Sony.


title: Amy Pascal

text: Pascal started her own production company, with a four-year contract for funding and distribution via Sony Pictures Entertainment. The company, called Pascal Pictures, hired Rachel O'Connor as production chief and Ian Dalrymple to open and run a New York branch. Pascal Pictures was expected to continue Amy Pascal's "book-friendly" focus, and Dalrymple's office was expected to facilitate this. She produced the "Ghostbusters" reboot film and the Marvel Studios-produced "", in addition to theatre and television work. TriStar President Hannah Minghella obtained rights to "Maestra" by L. S. Hilton with the intent for Pascal to produce the film. Pascal Pictures made a winning bid for a memoir by Zoë Quinn about "Gamergate" called "Crash Override: How to Save the Internet from Itself", which was sold to Touchstone/Simon & Schuster for publication in September 2016. Pascal and Elizabeth Cantillon optioned rights for a TriStar TV series based on books by Eve Babitz set in 1960s-1970s Los Angeles. For a sum in the "mid-six to seven figures", Pascal made a deal for Michael Diliberti's "Athena", about a descendant of the goddess Athena who is recruited to a secret organization. Together with Sony, Pascal obtained rights for the TV crime drama "Darktown", which she plans to executive produce with Jamie Foxx.


title: Amy Pascal

text: In May 2019, it was announced that Pascal and her production company Pascal Pictures is leaving Sony and moving to Universal Pictures for a first-look deal after 30 years at Sony Pictures.


title: Amy Pascal

text: In 2001, Pascal was honored with the Women in Film's Crystal Award, which recognizes those whose work has helped to expand the role of women in the entertainment industry. Pascal has been included in "The Hollywood Reporter"s annual Women in Entertainment Power 100 list and "Forbes" ranking of the World's 100 Most Powerful Women. , she was ranked as the 28th most powerful woman in the world by "Forbes", up from 36th in 2013.


title: Amy Pascal

text: Pascal serves on the Honorary Committee of the Epilepsy Foundation of Greater Los Angeles. She has made charitable contributions to Teen Line.


title: Amy Pascal

text: She was awarded the 2008 Humanitarian Award from the Simon Wiesenthal Center, a non-profit organization based in Los Angeles which combats antisemitism and promotes human rights and tolerance. She received the award at the 2008 National Tribute Dinner, an annual fundraiser which raised US$2 million for the center. In her acceptance speech, she said, "I believe in what the museum is committed to: not just the literal event of the Holocaust but not letting anything like that happen again."


title: Amy Pascal

text: In August 2014, in the wake of the 2014 Israel–Gaza conflict, alongside more than 190 members of the Hollywood entertainment industry, she signed a petition condemning Hamas started by Creative Community for Peace, a pro-peace non-profit organization. The petition read in part, "Hamas cannot be allowed to rain rockets on Israeli cities, nor can it be allowed to hold its own people hostage. Hospitals are for healing, not for hiding weapons. Schools are for learning, not for launching missiles. Children are our hope, not our human shields."


title: Amy Pascal

text: On December 9, 2014, a group called "Guardians of Peace" hacked into Sony's computer system, which led to the theft of internal company documents. The fallout became a major international diplomatic incident in North Korea–United States relations. In subsequent news coverage Pascal and producer Scott Rudin were noted to have had an exchange in these documents about Pascal's upcoming encounter with President Barack Obama. Pascal joked that the president, who is black, would possibly enjoy "Django Unchained" and "The Butler" (films which deal with slavery in the United States and the pre-civil rights era) or the comedy "Think Like a Man" which features an ensemble cast of black comedians. Rudin responded, ""Ride Along", I bet he likes Kevin Hart."


title: Amy Pascal

text: News reports branded the exchange as "racially insensitive," while others called it "racist." Pascal responded by saying "the content of my emails were insensitive and inappropriate but are not an accurate reflection of who I am."


title: Amy Pascal

text: Civil rights leader Al Sharpton suggested the apology was not sufficient, compared her to Donald Sterling, and called for more diversity in Sony's hiring pool. The screenwriter and producer Aaron Sorkin denounced the media's focus on Pascal's communications and many other emails released by the hack in an opinion piece for "The New York Times", characterising the coverage as "giving material aid to criminals" and writing "at least the hackers are doing it for a cause. The press is doing it for a nickel." In the popular press, coverage of the story was extended with actress and producer Lisa Kudrow suggesting Pascal should have known better, adding, "Don't write anything you don't want broadcast". At the Writers Guild of America Awards 2014 on January 7, 2015, Kudrow, who was the presenter, mentioned the Sony hack again, arguing that it was disturbing "because Scott Rudin and Amy Pascal thought "that" was witty banter."


title: Amy Pascal

text: Color of Change, a civil rights organization, launched a petition in December 2014 calling upon Sony to fire Pascal from her role, arguing, "Pascal's comments are confirmation of the manipulative, exploitative relationship corporations like Sony have with Black folks." They added, "We must hold Pascal accountable here; not just for her horrendous comments, but also for her role at the helm of a corporate agenda that views Black America as one big, lucrative joke."


title: Amy Pascal

text: In a 2020 interview with "Vulture", Thandiwe Newton accused Pascal of making racially insensitive and demeaning demands of her for the film remake of "Charlie's Angels", a film Newton ended up declining to star in due to Pascal's alleged behavior. Pascal responded by stating she was "horrified" by the story and had no recollection of it.


title: Amy Pascal

text: After Pascal left Sony, she was interviewed about Sony Entertainment's gender pay gap that had been exposed by the leaks. Tina Brown asked Pascal to explain why actresses did not realize they were being paid less than male actors. Pascal said, "People want to work for less money. I'll pay them less money. I don't call them up and go, 'Can I give you some more?' ... what women have to do is not work for less money... People should know what they're worth and say no."


title: Amy Pascal

text: Women making less than their male counterparts and male co-stars learned of the difference from the hack, such as actress Charlize Theron, who had been able to obtain a deal of more than $10 million in early January 2015 to match the fee of Chris Hemsworth, her male co-star in "The Huntsman" film production. The difference between what men and women made was pervasive at Sony Pictures under Pascal, with only one female out of the seventeen studio executives earning more than $1 million per year according to the unconfirmed emails, and Columbia Pictures co-presidents of production Michael De Luca and Hannah Minghella serving in identical jobs but with a million dollar difference in pay.


title: Amy Pascal

text: In 2016, Pascal launched her production company Pascal Pictures which produced their first film "Ghostbusters".


title: Amy Pascal

text: Pascal married Bernard Weinraub, a former foreign correspondent for "The New York Times" and playwright, in 1997. They reside in Brentwood, Los Angeles, with their son Anthony Weinraub.


title: Gomorrah (TV series)

text: Gomorrah () is an Italian crime drama television series created by Roberto Saviano for Sky Atlantic. Based on Saviano's book of the same name, the show premiered on Sky Atlantic in Italy on 6 May 2014 and ran for five seasons; the final season aired in 2021. The 2008 film of the same name is loosely based on the same book, but unrelated to the TV series.


title: Gomorrah (TV series)

text: The show, largely filmed in the Scampia neighbourhood of Naples, tells the story of Ciro Di Marzio (Marco D'Amore), a member of the Camorra's Savastano clan, headed by Pietro Savastano (Fortunato Cerlino), a high-ranking member. Ciro aims to navigate the dangers of the criminal world, while also fighting a brutal civil war. The Savastano family also consists of his wife Immacolata (Maria Pia Calzone) and son, Gennaro (Salvatore Esposito). The show also features rival crime boss Salvatore Conte (Marco Palvetti), while introducing the characters Annalisa Magliocca (Cristina Donadio), Patrizia Santore (Cristiana Dell'Anna), Giuseppe Avitabile (Gianfranco Gallo) and Enzo "Sangueblù" Villa (Arturo Muselli) in the show's later seasons.


title: Gomorrah (TV series)

text: The series has gained critical acclaim for its characterization, pacing, atmosphere, acting, directing, and writing. It has also become a ratings hit for Sky, regularly featuring as one of the network's most-watched cable shows.


title: Gomorrah (TV series)

text: The series has been sold in 190 countries worldwide. It premiered in the United Kingdom on Sky Atlantic on 4 August 2014; in the United States it debuted on SundanceTV on 24 August 2016 for the first two seasons, and continued on HBO Max since 22 January 2021. The spin-off film "The Immortal", which is both a prequel and a sequel to the events after the series' third season, was released on 5 December 2019.


title: Gomorrah (TV series)

text: Set in Naples in the 2010s, the series follows Ciro Di Marzio, a member in the Savastano Camorra clan of Secondigliano, headed by Pietro Savastano. When Pietro is arrested, an internal power struggle breaks out with his rivals as well as between the "old guard" of the clan and the "young guard" headed by his son Gennaro Savastano. Ciro and Gennaro eventually find themselves at odds with their own families, and the several alliances they make with various criminal groups, as they navigate the Naples underworld.


title: Gomorrah (TV series)

text: In Naples, the Savastano clan is commanded by the dreaded and respected Pietro Savastano. Looking to make his mark, Ciro Di Marzio is tasked to burn the house of the mother of Salvatore Conte, a rival drug lord. After completing the task without hesitation and slowly gaining the trust of Pietro, the elder Savastano later entrusts Ciro to ready his son Gennaro to become the future head of the clan.


title: Gomorrah (TV series)

text: Following a police check, Pietro is arrested and taken into custody; control of the clan unofficially passes into the hands of his wife, Immacolata, who deems Ciro and Gennaro unable to run the clan in Pietro's absence. Immacolata, who maintains a dislike for Ciro, orders him to travel to Spain in order to make-up with Conte and reunite the clans. She later tasks Gennaro to travel to Honduras, hoping his interactions with drug producers will fast-track his development into becoming head of the clan. Despite being able to make peace with Conte, Ciro is frozen out by Immacolata, a sentiment that is shared by Gennaro once he returns to Naples. Gennaro, becoming more detached and isolated, begins a cleanup of the clan's members, inviting more younger comrades, while engaging in actions that grow distrust amongst the old guard, including Ciro, who find Gennaro unable to handle the clan. A civil war then ensues between the two factions of the Savastano clan: the old guard who are faithful to Pietro and the younger members who are faithful to Gennaro.


title: Gomorrah (TV series)

text: Ciro, feeling ignored and devalued by Gennaro, aligns with the old guard, seeking to shift the internal equilibrium of the clan. Ciro also solicits support from Conte, managing to obtain Conte's respect during his trip to Spain. Ciro begins by killing Immacolata; however, Gennaro quickly discovers Ciro's betrayal and, no longer knowing whom to trust, enlists the members loyal to him in order to dismantle the old guard he believes to be Ciro's accomplices. Gennaro largely succeeds, killing everyone besides Ciro and Malammore, both of whom manage to go into hiding. Gennaro later discovers Ciro's whereabouts, sending the members loyal to him to kill him, but they are intercepted and brutally massacred by Conte's clan. Gennaro is later shot by Ciro, while Malammore breaks Pietro out of a police transport van during a prison transfer.


title: Gomorrah (TV series)

text: Following his escape from prison, Pietro realizes that his stay in Naples will be short-lived, and promptly flees to Cologne, leaving the clan in the hands of Malammore and the rest of the members that aided his escape. He also plots to seek vengeance on the people who ambushed Gennaro, who survived his shooting. Ciro, meanwhile, forms an alliance with Conte, at the expense of his relationship with his wife, Debora.


title: Gomorrah (TV series)

text: A year later, Gennaro is healed from his injuries and reunites with his father in Germany, where they align with the Avitabiles. After an arms deal goes awry, Pietro becomes wary of his power waning, and decides to return to Naples alone to resume control of the clan. Ciro and other members of Conte's clan encounter trouble with Conte, disliking his aims at creating a monopoly and gaining absolute power. They then devise a successful scheme to kill him. Pietro views this as the perfect opportunity to exact revenge, taking advantage of the disjointed clan by murdering several of them. Ciro learns of Pietro's return, and wishes to negotiate a settlement. Malammore's niece, Patrizia, informs Ciro that he will only be able to negotiate with Gennaro. Wary of a potential ambush, Ciro goes to Giuseppe, a mutual friend of his and Gennaro's, to act as guarantor during their negotiations. Gennaro eventually accepts the settlement conditions set by Ciro, which infuriates Pietro. Gennaro explains killing Ciro would have caused a war without any boundaries and expresses his wish to focus on business.


title: Gomorrah (TV series)

text: Pietro rejects the settlement, and continues to wage war, revealing to Patrizia that he wishes to defeat his son for undermining him. He is also suspicious of Patrizia's loyalties. After violently killing another member of the clan, he plants evidence to make it appear as though the murder was a result of in-house betrayal. In-fighting then becomes rife within the clan. However, after failing to subvert another member, Ciro learns of the true murderer and informs Gennaro. After Pietro murders Ciro's daughter, Ciro decides to murder Pietro. Disgusted by his father's actions, while also wishing to raise his son, named Pietro after his grandfather, in a world without in-fighting or violence, Gennaro agrees and informs Ciro of Pietro's whereabouts. Ciro murders Pietro at the Savastano family plot.


title: Gomorrah (TV series)

text: Gennaro assumes full control of all drug trade in Naples. He becomes feared and respected among the underworld. However, Ciro loses the will to continue, and after killing Malammore to avenge his daughter, moves to Sofia to work for Valentin, an associate. He later finds out Mladen (Valentin's son) tried to set him up, and since he's Valentin's successor, he hesitantly orders Ciro's death. Ciro however, murders Valentin and his son Mladen, and returns to Naples, while Giuseppe is in prison after Gennaro reveals his criminal past to the police.


title: Gomorrah (TV series)

text: Giuseppe quickly avoids jail time by agreeing to a plea deal, and is placed on house arrest instead. He then orders the systematic destruction of Gennaro and his criminal empire, robbing and killing his lieutenants, which leaves him isolated in his war against Giuseppe. Gennaro then seeks assistance from Ciro and Annalisa, who are both eager to return to power. Ciro initially aims to locate allies outside Naples, however, he meets Enzo and Valerio, members of the Santo clan, who convince him only people from the city truly wish for Giuseppe's demise. Together, they help Gennaro resume business, while Gennaro also bribes lawmakers and police officials to aid his cause.


title: Gomorrah (TV series)

text: However, Enzo begins to have reservations when many of his men begin to die at the hands of the Confederates, and wishes to leave. The Confederates, outraged, attempt to murder his sister by bombing the restaurant she works at, which begins a war between Enzo and Valerio, against them. Ciro desperately proposes an armistice, which is reluctantly accepted. Enzo's reservations are maintained, however, which forces Gennaro to kill his sister, which he then blames on Arenella (a member of the Confederates). This increases Enzo's involvement, and they successfully organize an ambush on Giuseppe and Arenella.


title: Gomorrah (TV series)

text: Following this, Ciro pushes Gennaro to create peace with all their enemies. Peace is eventually accepted, and Gennaro divides the city and other land to the people who helped him win. Patrizia later kills Annalisa, which arouses Enzo's suspicions, as Patrizia vocally opposed murder during the war. He later stalks her, and learns Gennaro was involved in his sister's murder. Inviting both him and Ciro on his yacht under the pretense of celebration, Enzo reveals his intentions to kill Gennaro. Prior to shooting him, however, Ciro sacrifices himself in his place by admitting to murdering his sister, stating his desire to avoid another war, and wishing to re-join his family in heaven. Enzo then forces Gennaro to kill Ciro.


title: Gomorrah (TV series)

text: The show's first season premiered on Sky Atlantic and Sky Cinema 1 in Italy on 6 May 2014. It also aired on Rai 3 on 10 January 2015. Season 2 aired on 10 May 2016, season 3 on 17 November 2017, and season 4 on 29 March 2019. The fifth season was released in 2021.


title: Gomorrah (TV series)

text: After the success on television, the series also had a limited theatrical release by The Space Movies and Universal Pictures. The first season was screened on 200 Italian theaters from 22 September 2014, with three episodes per evening (150 minutes) for four consecutive Mondays.


title: Gomorrah (TV series)

text: The show's success has spawned its release to international markets, being sold in 190 countries worldwide. It premiered in the United Kingdom on Sky Atlantic on 4 August 2014, and in the United States on SundanceTV on 24 August 2016. The series was also released on Netflix in some countries (including in the US, Australia and New Zealand) and on SBS on Demand in Australia from 16 October 2020.


title: Gomorrah (TV series)

text: All the episodes and the movie are also set to be released on HBO Max in the US; season 3 debuted on 21 January 2021.


title: Gomorrah (TV series)

text: "Gomorrah" is one of Sky's most-watched cable shows, and has gained critical acclaim for its characterization, pacing, atmosphere, acting, directing, and writing. The first season holds a 95% rating on review aggregation website Rotten Tomatoes, based on 19 reviews and with an average rating of 7.31/10. The website's critics consensus reads: ""Gomorrah" brings a refreshing twist to a familiar story, with its realistic, unglamorous and often riveting portrayal of a Neapolitan crime organization organization". On Metacritic, it has a rating of 76 out of 100, based on 15 reviews.


title: Gomorrah (TV series)

text: Ben Travers of "IndieWire" called it the "darker, grown-up version of "The Sopranos"" and stated, "Despite its familiar construction, "Gomorrah" is significantly more frightening than others in its genre because of the history behind it." Mary McNamara of "The Los Angeles Times" wrote: "Aggressively dark, focused to the point of claustrophobia and often all but choking on its own authenticity, "Gomorrah" shocks the system like a real Italian espresso after years of skinny vanilla lattes ... in "Gomorrah", familiarity breeds relief rather than contempt." Brian Moylan of "The Guardian" stated, "For those who like mafia shows and the sort of anti-hero dramas that have become the stock in trade of 'peak TV', this is another excellent entry." "Sight & Sound" called the series "Italy's answer to "Breaking Bad"."


title: Gomorrah (TV series)

text: However, the show has received criticism from several Italian politicians. Naples mayor Luigi de Magistris claimed that bouts of violent crimes skyrocket in the city whenever an episode of the series is aired. He also added that the series "is likely to corrode the brains, souls, and hearts of hundreds of very young people." Anti-Mafia magistrate Giuseppe Borrelli has stated, "The series fails to capture any aspect of today's Camorra", the national anti-mafia prosecutor Federico Cafiero de Raho has stated, "it humanizes gangsters", while the state prosecutor in Catanzaro Nicola Gratteri has stated, "It makes them seem likable, which is dangerous."


title: Gomorrah (TV series)

text: A spin-off film titled "The Immortal" ("L'immortale") was released in theaters on 5 December 2019. The film is both a prequel and a sequel to the events after the series' third season, and stars Marco D'Amore reprising his role as Ciro Di Marzio.


title: Ionizing radiation

text: Ionizing radiation (or ionising radiation), including nuclear radiation, consists of subatomic particles or electromagnetic waves that have sufficient energy to ionize atoms or molecules by detaching electrons from them. Some particles can travel up to 99% of the speed of light, and the electromagnetic waves are on the high-energy portion of the electromagnetic spectrum.


title: Ionizing radiation

text: Gamma rays, X-rays, and the higher energy ultraviolet part of the electromagnetic spectrum are ionizing radiation, whereas the lower energy ultraviolet, visible light, nearly all types of laser light, infrared, microwaves, and radio waves are non-ionizing radiation. The boundary between ionizing and non-ionizing radiation in the ultraviolet area is not sharply defined, as different molecules and atoms ionize at different energies. The energy of ionizing radiation starts between 10 electronvolts (eV) and 33 eV.


title: Ionizing radiation

text: Typical ionizing subatomic particles include alpha particles, beta particles, and neutrons. These are typically created by radioactive decay, and almost all are energetic enough to ionize. There are also secondary cosmic particles produced after cosmic rays interact with Earth's atmosphere, including muons, mesons, and positrons. Cosmic rays may also produce radioisotopes on Earth (for example, carbon-14), which in turn decay and emit ionizing radiation. Cosmic rays and the decay of radioactive isotopes are the primary sources of natural ionizing radiation on Earth, contributing to background radiation. Ionizing radiation is also generated artificially by X-ray tubes, particle accelerators, and nuclear fission.


title: Ionizing radiation

text: Ionizing radiation is not immediately detectable by human senses, so instruments such as Geiger counters are used to detect and measure it. However, very high energy particles can produce visible effects on both organic and inorganic matter (e.g. water lighting in Cherenkov radiation) or humans (e.g. acute radiation syndrome).


title: Ionizing radiation

text: Ionizing radiation is used in a wide variety of fields such as medicine, nuclear power, research, and industrial manufacturing, but presents a health hazard if proper measures against excessive exposure are not taken. Exposure to ionizing radiation causes cell damage to living tissue and organ damage. In high acute doses, it will result in radiation burns and radiation sickness, and lower level doses over a protracted time can cause cancer. The International Commission on Radiological Protection (ICRP) issues guidance on ionizing radiation protection, and the effects of dose uptake on human health.


title: Ionizing radiation

text: Any charged particle with mass can ionize atoms directly by fundamental interaction through the Coulomb force if it carries sufficient kinetic energy. Such particles include atomic nuclei, electrons, muons, charged pions, protons, and energetic charged nuclei stripped of their electrons. When moving at relativistic speeds (near the speed of light, c) these particles have enough kinetic energy to be ionizing, but there is considerable speed variation. For example, a typical alpha particle moves at about 5% of c, but an electron with 33 eV (just enough to ionize) moves at about 1% of c.


title: Ionizing radiation

text: Two of the first types of directly ionizing radiation to be discovered are alpha particles which are helium nuclei ejected from the nucleus of an atom during radioactive decay, and energetic electrons, which are called beta particles.


title: Ionizing radiation

text: Natural cosmic rays are made up primarily of relativistic protons but also include heavier atomic nuclei like helium ions and HZE ions. In the atmosphere such particles are often stopped by air molecules, and this produces short-lived charged pions, which soon decay to muons, a primary type of cosmic ray radiation that reaches the surface of the earth. Pions can also be produced in large amounts in particle accelerators.


title: Ionizing radiation

text: Alpha particles consist of two protons and two neutrons bound together into a particle identical to a helium nucleus. Alpha particle emissions are generally produced in the process of alpha decay.


title: Ionizing radiation

text: Alpha particles are a strongly ionizing form of radiation, but when emitted by radioactive decay they have low penetration power and can be absorbed by a few centimeters of air, or by the top layer of human skin. More powerful alpha particles from ternary fission are three times as energetic, and penetrate proportionately farther in air. The helium nuclei that form 10–12% of cosmic rays, are also usually of much higher energy than those produced by radioactive decay and pose shielding problems in space. However, this type of radiation is significantly absorbed by the Earth's atmosphere, which is a radiation shield equivalent to about 10 meters of water.


title: Ionizing radiation

text: The alpha particle was named by Ernest Rutherford after the first letter in the Greek alphabet, α, when he ranked the known radioactive emissions in descending order of ionising effect in 1899. The symbol is α or α. Because they are identical to helium nuclei, they are also sometimes written as or indicating a Helium ion with a +2 charge (missing its two electrons). If the ion gains electrons from its environment, the alpha particle can be written as a normal (electrically neutral) helium atom .


title: Ionizing radiation

text: Beta particles are high-energy, high-speed electrons or positrons emitted by certain types of radioactive nuclei, such as potassium-40. The production of beta particles is termed beta decay. They are designated by the Greek letter beta (β). There are two forms of beta decay, β and β, which respectively give rise to the electron and the positron. Beta particles are less penetrating than gamma radiation, but more penetrating than alpha particles.


title: Ionizing radiation

text: High-energy beta particles may produce X-rays known as bremsstrahlung ("braking radiation") or secondary electrons (delta ray) as they pass through matter. Both of these can cause an indirect ionization effect. Bremsstrahlung is of concern when shielding beta emitters, as the interaction of beta particles with some shielding materials produces Bremsstrahlung. The effect is greater with material having high atomic numbers, so material with low atomic numbers is used for beta source shielding.


title: Ionizing radiation

text: The positron or antielectron is the antiparticle or the antimatter counterpart of the electron. When a low-energy positron collides with a low-energy electron, annihilation occurs, resulting in their conversion into the energy of two or more gamma ray photons (see electron–positron annihilation). As positrons are positively charged particles they can directly ionize an atom through Coulomb interactions.


title: Ionizing radiation

text: Positrons can be generated by positron emission nuclear decay (through weak interactions), or by pair production from a sufficiently energetic photon. Positrons are common artificial sources of ionizing radiation used in medical positron emission tomography (PET) scans.


title: Ionizing radiation

text: Charged nuclei are characteristic of galactic cosmic rays and solar particle events and except for alpha particles (charged helium nuclei) have no natural sources on the earth. In space, however, very high energy protons, helium nuclei, and HZE ions can be initially stopped by relatively thin layers of shielding, clothes, or skin. However, the resulting interaction will generate secondary radiation and cause cascading biological effects. If just one atom of tissue is displaced by an energetic proton, for example, the collision will cause further interactions in the body. This is called "linear energy transfer" (LET), which utilizes elastic scattering.


title: Ionizing radiation

text: LET can be visualized as a billiard ball hitting another in the manner of the conservation of momentum, sending both away with the energy of the first ball divided between the two unequally. When a charged nucleus strikes a relatively slow-moving nucleus of an object in space, LET occurs and neutrons, alpha particles, low-energy protons, and other nuclei will be released by the collisions and contribute to the total absorbed dose of tissue.<ref name="NASA/TP-1999-209320"> Kim, Myung-Hee Y.; Wilson, John W.; Cucinotta, Francis A.; Simonsen, Lisa C.; Atwell, William; Badavi, Francis F.; Miller, Jack, NASA Johnson Space Center; Langley Research Center, May 1999.</ref>


title: Ionizing radiation

text: Indirectly ionizing radiation is electrically neutral and does not interact strongly with matter, therefore the bulk of the ionization effects are due to secondary ionization.


title: Ionizing radiation

text: Even though photons are electrically neutral, they can ionize atoms indirectly through the photoelectric effect and the Compton effect. Either of those interactions will cause the ejection of an electron from an atom at relativistic speeds, turning that electron into a beta particle (secondary beta particle) that will ionize other atoms. Since most of the ionized atoms are due to the secondary beta particles, photons are indirectly ionizing radiation.


title: Ionizing radiation

text: Radiated photons are called gamma rays if they are produced by a nuclear reaction, subatomic particle decay, or radioactive decay within the nucleus. They are called x-rays if produced outside the nucleus. The generic term "photon" is used to describe both.


title: Ionizing radiation

text: X-rays normally have a lower energy than gamma rays, and an older convention was to define the boundary as a wavelength of 10 m (or a photon energy of 100 keV). That threshold was driven by historic limitations of older X-ray tubes and low awareness of isomeric transitions. Modern technologies and discoveries have shown an overlap between X-ray and gamma energies. In many fields they are functionally identical, differing for terrestrial studies only in origin of the radiation. In astronomy, however, where radiation origin often cannot be reliably determined, the old energy division has been preserved, with X-rays defined as being between about 120 eV and 120 keV, and gamma rays as being of any energy above 100 to 120 keV, regardless of source. Most astronomical "gamma-ray astronomy" are known "not" to originate in nuclear radioactive processes but, rather, result from processes like those that produce astronomical X-rays, except driven by much more energetic electrons.


title: Ionizing radiation

text: Photoelectric absorption is the dominant mechanism in organic materials for photon energies below 100 keV, typical of classical X-ray tube originated X-rays. At energies beyond 100 keV, photons ionize matter increasingly through the Compton effect, and then indirectly through pair production at energies beyond 5 MeV. The accompanying interaction diagram shows two Compton scatterings happening sequentially. In every scattering event, the gamma ray transfers energy to an electron, and it continues on its path in a different direction and with reduced energy.


title: Ionizing radiation

text: The lowest ionization energy of any element is 3.89 eV, for caesium. However, US Federal Communications Commission material defines ionizing radiation as that with a photon energy greater than 10 eV (equivalent to a far ultraviolet wavelength of 124 nanometers). Roughly, this corresponds to both the first ionization energy of oxygen, and the ionization energy of hydrogen, both about 14 eV. In some Environmental Protection Agency references, the ionization of a typical water molecule at an energy of 33 eV is referenced as the appropriate biological threshold for ionizing radiation: this value represents the so-called "W-value", the colloquial name for the ICRU's mean energy expended in a gas per ion pair formed, which combines ionization energy plus the energy lost to other processes such as excitation. At 38 nanometers wavelength for electromagnetic radiation, 33 eV is close to the energy at the conventional 10 nm wavelength transition between extreme ultraviolet and X-ray radiation, which occurs at about 125 eV. Thus, X-ray radiation is always ionizing, but only extreme-ultraviolet radiation can be considered ionizing under all definitions.


title: Ionizing radiation

text: Neutrons have a neutral electrical charge often misunderstood as zero electrical charge and thus often do not "directly" cause ionization in a single step or interaction with matter. However, fast neutrons will interact with the protons in hydrogen via linear energy transfer, energy that a particle transfers to the material it is moving through. This mechanism scatters the nuclei of the materials in the target area, causing direct ionization of the hydrogen atoms. When neutrons strike the hydrogen nuclei, proton radiation (fast protons) results. These protons are themselves ionizing because they are of high energy, are charged, and interact with the electrons in matter.


title: Ionizing radiation

text: Neutrons that strike other nuclei besides hydrogen will transfer less energy to the other particle if linear energy transfer does occur. But, for many nuclei struck by neutrons, inelastic scattering occurs. Whether elastic or inelastic scatter occurs is dependent on the speed of the neutron, whether fast or thermal or somewhere in between. It is also dependent on the nuclei it strikes and its neutron cross section.


title: Ionizing radiation

text: In inelastic scattering, neutrons are readily absorbed in a type of nuclear reaction called neutron capture and attributes to the neutron activation of the nucleus. Neutron interactions with most types of matter in this manner usually produce radioactive nuclei. The abundant oxygen-16 nucleus, for example, undergoes neutron activation, rapidly decays by a proton emission forming nitrogen-16, which decays to oxygen-16. The short-lived nitrogen-16 decay emits a powerful beta ray. This process can be written as:


title: Ionizing radiation

text: This high-energy β further interacts rapidly with other nuclei, emitting high-energy γ via Bremsstrahlung


title: Ionizing radiation

text: While not a favorable reaction, the O (n,p) N reaction is a major source of X-rays emitted from the cooling water of a pressurized water reactor and contributes enormously to the radiation generated by a water-cooled nuclear reactor while operating.


title: Ionizing radiation

text: In fissile materials, secondary neutrons may produce nuclear chain reactions, causing a larger amount of ionization from the daughter products of fission.


title: Ionizing radiation

text: Outside the nucleus, free neutrons are unstable and have a mean lifetime of 14 minutes, 42 seconds. Free neutrons decay by emission of an electron and an electron antineutrino to become a proton, a process known as beta decay:


title: Ionizing radiation

text: In the adjacent diagram, a neutron collides with a proton of the target material, and then becomes a fast recoil proton that ionizes in turn. At the end of its path, the neutron is captured by a nucleus in an (n,γ)-reaction that leads to the emission of a neutron capture photon. Such photons always have enough energy to qualify as ionizing radiation.


title: Ionizing radiation

text: Neutron radiation, alpha radiation, and extremely energetic gamma (> ~20 MeV) can cause nuclear transmutation and induced radioactivity. The relevant mechanisms are neutron activation, alpha absorption, and photodisintegration. A large enough number of transmutations can change macroscopic properties and cause targets to become radioactive themselves, even after the original source is removed.


title: Ionizing radiation

text: Ionization of molecules can lead to radiolysis (breaking chemical bonds), and formation of highly reactive free radicals. These free radicals may then react chemically with neighbouring materials even after the original radiation has stopped. (e.g., ozone cracking of polymers by ozone formed by ionization of air). Ionizing radiation can also accelerate existing chemical reactions such as polymerization and corrosion, by contributing to the activation energy required for the reaction. Optical materials deteriorate under the effect of ionizing radiation.


title: Ionizing radiation

text: High-intensity ionizing radiation in air can produce a visible ionized air glow of telltale bluish-purple color. The glow can be observed, e.g., during criticality accidents, around mushroom clouds shortly after a nuclear explosion, or the inside of a damaged nuclear reactor like during the Chernobyl disaster.


title: Ionizing radiation

text: Monatomic fluids, e.g. molten sodium, have no chemical bonds to break and no crystal lattice to disturb, so they are immune to the chemical effects of ionizing radiation. Simple diatomic compounds with very negative enthalpy of formation, such as hydrogen fluoride will reform rapidly and spontaneously after ionization.


title: Ionizing radiation

text: Ionization of materials temporarily increases their conductivity, potentially permitting damaging current levels. This is a particular hazard in semiconductor microelectronics employed in electronic equipment, with subsequent currents introducing operation errors or even permanently damaging the devices. Devices intended for high radiation environments such as the nuclear industry and extra-atmospheric (space) applications may be made "radiation hard" to resist such effects through design, material selection, and fabrication methods.


title: Ionizing radiation

text: Proton radiation found in space can also cause single-event upsets in digital circuits. The electrical effects of ionizing radiation are exploited in gas-filled radiation detectors, e.g. the Geiger-Muller counter or the ion chamber.


title: Ionizing radiation

text: Most adverse health effects of exposure to ionizing radiation may be grouped in two general categories:


title: Ionizing radiation

text: The most common impact is stochastic induction of cancer with a latent period of years or decades after exposure. For example, ionizing radiation is one cause of chronic myelogenous leukemia, although most people with CML have not been exposed to radiation. The mechanism by which this occurs is well understood, but quantitative models predicting the level of risk remain controversial.


title: Ionizing radiation

text: The most widely accepted model, the Linear no-threshold model (LNT), holds that the incidence of cancers due to ionizing radiation increases linearly with effective radiation dose at a rate of 5.5% per sievert. If this is correct, then natural background radiation is the most hazardous source of radiation to general public health, followed by medical imaging as a close second. Other stochastic effects of ionizing radiation are teratogenesis, cognitive decline, and heart disease.


title: Ionizing radiation

text: Although DNA is always susceptible to damage by ionizing radiation, the DNA molecule may also be damaged by radiation with enough energy to excite certain molecular bonds to form pyrimidine dimers. This energy may be less than ionizing, but near to it. A good example is ultraviolet spectrum energy which begins at about 3.1 eV (400 nm) at close to the same energy level which can cause sunburn to unprotected skin, as a result of photoreactions in collagen and (in the UV-B range) also damage in DNA (for example, pyrimidine dimers). Thus, the mid and lower ultraviolet electromagnetic spectrum is damaging to biological tissues as a result of electronic excitation in molecules which falls short of ionization, but produces similar non-thermal effects. To some extent, visible light and also ultraviolet A (UVA) which is closest to visible energies, have been proven to result in formation of reactive oxygen species in skin, which cause indirect damage since these are electronically excited molecules which can inflict reactive damage, although they do not cause sunburn (erythema). Like ionization-damage, all these effects in skin are beyond those produced by simple thermal effects.


title: Ionizing radiation

text: Ionizing radiation has many industrial, military, and medical uses. Its usefulness must be balanced with its hazards, a compromise that has shifted over time. For example, at one time, assistants in shoe shops used X-rays to check a child's shoe size, but this practice was halted when the risks of ionizing radiation were better understood.


title: Ionizing radiation

text: Neutron radiation is essential to the working of nuclear reactors and nuclear weapons. The penetrating power of x-ray, gamma, beta, and positron radiation is used for medical imaging, nondestructive testing, and a variety of industrial gauges. Radioactive tracers are used in medical and industrial applications, as well as biological and radiation chemistry. Alpha radiation is used in static eliminators and smoke detectors. The sterilizing effects of ionizing radiation are useful for cleaning medical instruments, food irradiation, and the sterile insect technique. Measurements of carbon-14, can be used to date the remains of long-dead organisms (such as wood that is thousands of years old).


title: Ionizing radiation

text: Ionizing radiation is generated through nuclear reactions, nuclear decay, by very high temperature, or via acceleration of charged particles in electromagnetic fields. Natural sources include the sun, lightning and supernova explosions. Artificial sources include nuclear reactors, particle accelerators, and x-ray tubes.


title: Ionizing radiation

text: The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) itemized types of human exposures.


title: Ionizing radiation

text: The International Commission on Radiological Protection manages the International System of Radiological Protection, which sets recommended limits for dose uptake.


title: Ionizing radiation

text: The global average exposure of humans to ionizing radiation is about 3 mSv (0.3 rem) per year, 80% of which comes from nature. The remaining 20% results from exposure to man-made radiation sources, primarily from medical imaging. Average man-made exposure is much higher in developed countries, mostly due to CT scans and nuclear medicine.


title: Ionizing radiation

text: Natural background radiation comes from five primary sources: cosmic radiation, solar radiation, external terrestrial sources, radiation in the human body, and radon.


title: Ionizing radiation

text: The background rate for natural radiation varies considerably with location, being as low as 1.5 mSv/a (1.5 mSv per year) in some areas and over 100 mSv/a in others. The highest level of purely natural radiation recorded on the Earth's surface is 90 µGy/h (0.8 Gy/a) on a Brazilian black beach composed of monazite. The highest background radiation in an inhabited area is found in Ramsar, primarily due to naturally radioactive limestone used as a building material. Some 2000 of the most exposed residents receive an average radiation dose of 10 mGy per year, (1 rad/yr) ten times more than the ICRP recommended limit for exposure to the public from artificial sources. Record levels were found in a house where the effective radiation dose due to external radiation was 135 mSv/a, (13.5 rem/yr) and the committed dose from radon was 640 mSv/a (64.0 rem/yr). This unique case is over 200 times higher than the world average background radiation. Despite the high levels of background radiation that the residents of Ramsar receive there is no compelling evidence that they experience a greater health risk. The ICRP recommendations are conservative limits and may represent an over representation of the actual health risk. Generally radiation safety organization recommend the most conservative limits assuming it is best to err on the side of caution. This level of caution is appropriate but should not be used to create fear about background radiation danger. Radiation danger from background radiation may be a serious threat but is more likely a small overall risk compared to all other factors in the environment.


title: Ionizing radiation

text: The Earth, and all living things on it, are constantly bombarded by radiation from outside our solar system. This cosmic radiation consists of relativistic particles: positively charged nuclei (ions) from 1 amu protons (about 85% of it) to 26 amu iron nuclei and even beyond. (The high-atomic number particles are called HZE ions.) The energy of this radiation can far exceed that which humans can create, even in the largest particle accelerators (see ultra-high-energy cosmic ray). This radiation interacts in the atmosphere to create secondary radiation that rains down, including x-rays, muons, protons, antiprotons, alpha particles, pions, electrons, positrons, and neutrons.


title: Ionizing radiation

text: The dose from cosmic radiation is largely from muons, neutrons, and electrons, with a dose rate that varies in different parts of the world and based largely on the geomagnetic field, altitude, and solar cycle. The cosmic-radiation dose rate on airplanes is so high that, according to the United Nations UNSCEAR 2000 Report (see links at bottom), airline flight crew workers receive more dose on average than any other worker, including those in nuclear power plants. Airline crews receive more cosmic rays if they routinely work flight routes that take them close to the North or South pole at high altitudes, where this type of radiation is maximal.


title: Ionizing radiation

text: Cosmic rays also include high-energy gamma rays, which are far beyond the energies produced by solar or human sources.


title: Ionizing radiation

text: Most materials on Earth contain some radioactive atoms, even if in small quantities. Most of the dose received from these sources is from gamma-ray emitters in building materials, or rocks and soil when outside. The major radionuclides of concern for terrestrial radiation are isotopes of potassium, uranium, and thorium. Each of these sources has been decreasing in activity since the formation of the Earth.


title: Ionizing radiation

text: All earthly materials that are the building blocks of life contain a radioactive component. As humans, plants, and animals consume food, air, and water, an inventory of radioisotopes builds up within the organism (see banana equivalent dose). Some radionuclides, like potassium-40, emit a high-energy gamma ray that can be measured by sensitive electronic radiation measurement systems. These internal radiation sources contribute to an individual's total radiation dose from natural background radiation.


title: Ionizing radiation

text: An important source of natural radiation is radon gas, which seeps continuously from bedrock but can, because of its high density, accumulate in poorly ventilated houses.


title: Ionizing radiation

text: Radon-222 is a gas produced by the α-decay of radium-226. Both are a part of the natural uranium decay chain. Uranium is found in soil throughout the world in varying concentrations. Radon is the largest cause of lung cancer among non-smokers and the second-leading cause overall.


title: Ionizing radiation

text: These can all be applied to natural and man-made sources. For man-made sources the use of Containment is a major tool in reducing dose uptake and is effectively a combination of shielding and isolation from the open environment. Radioactive materials are confined in the smallest possible space and kept out of the environment such as in a hot cell (for radiation) or glove box (for contamination). Radioactive isotopes for medical use, for example, are dispensed in closed handling facilities, usually gloveboxes, while nuclear reactors operate within closed systems with multiple barriers that keep the radioactive materials contained. Work rooms, hot cells and gloveboxes have slightly reduced air pressures to prevent escape of airborne material to the open environment.


title: Ionizing radiation

text: In nuclear conflicts or civil nuclear releases civil defense measures can help reduce exposure of populations by reducing ingestion of isotopes and occupational exposure. One is the issue of potassium iodide (KI) tablets, which blocks the uptake of radioactive iodine (one of the major radioisotope products of nuclear fission) into the human thyroid gland.


title: Ionizing radiation

text: Occupationally exposed individuals are controlled within the regulatory framework of the country they work in, and in accordance with any local nuclear licence constraints. These are usually based on the recommendations of the International Commission on Radiological Protection.


title: Ionizing radiation

text: The ICRP recommends limiting artificial irradiation. For occupational exposure, the limit is 50 mSv in a single year with a maximum of 100 mSv in a consecutive five-year period.


title: Ionizing radiation

text: The radiation exposure of these individuals is carefully monitored with the use of dosimeters and other radiological protection instruments which will measure radioactive particulate concentrations, area gamma dose readings and radioactive contamination. A legal record of dose is kept.


title: Ionizing radiation

text: Some human-made radiation sources affect the body through direct radiation, known as effective dose (radiation) while others take the form of radioactive contamination and irradiate the body from within. The latter is known as committed dose.


title: Ionizing radiation

text: Medical procedures, such as diagnostic X-rays, nuclear medicine, and radiation therapy are by far the most significant source of human-made radiation exposure to the general public. Some of the major radionuclides used are I-131, Tc-99m, Co-60, Ir-192, and Cs-137. The public is also exposed to radiation from consumer products, such as tobacco (polonium-210), combustible fuels (gas, coal, etc.), televisions, luminous watches and dials (tritium), airport X-ray systems, smoke detectors (americium), electron tubes, and gas lantern mantles (thorium).


title: Ionizing radiation

text: Of lesser magnitude, members of the public are exposed to radiation from the nuclear fuel cycle, which includes the entire sequence from processing uranium to the disposal of the spent fuel. The effects of such exposure have not been reliably measured due to the extremely low doses involved. Opponents use a cancer per dose model to assert that such activities cause several hundred cases of cancer per year, an application of the widely accepted Linear no-threshold model (LNT).


title: Ionizing radiation

text: The International Commission on Radiological Protection recommends limiting artificial irradiation to the public to an average of 1 mSv (0.001 Sv) of effective dose per year, not including medical and occupational exposures.


title: Ionizing radiation

text: In a nuclear war, gamma rays from both the initial weapon explosion and fallout would be the sources of radiation exposure.


title: Ionizing radiation

text: Massive particles are a concern for astronauts outside the earth's magnetic field who would receive solar particles from solar proton events (SPE) and galactic cosmic rays from cosmic sources. These high-energy charged nuclei are blocked by Earth's magnetic field but pose a major health concern for astronauts traveling to the moon and to any distant location beyond the earth orbit. Highly charged HZE ions in particular are known to be extremely damaging, although protons make up the vast majority of galactic cosmic rays. Evidence indicates past SPE radiation levels that would have been lethal for unprotected astronauts.


title: Ionizing radiation

text: Air travel exposes people on aircraft to increased radiation from space as compared to sea level, including cosmic rays and from solar flare events. Software programs such as Epcard, CARI, SIEVERT, PCAIRE are attempts to simulate exposure by aircrews and passengers. An example of a measured dose (not simulated dose) is 6 μSv per hour from London Heathrow to Tokyo Narita on a high-latitude polar route. However, dosages can vary, such as during periods of high solar activity. The United States FAA requires airlines to provide flight crew with information about cosmic radiation, and an International Commission on Radiological Protection recommendation for the general public is no more than 1 mSv per year. In addition, many airlines do not allow pregnant flightcrew members, to comply with a European Directive. The FAA has a recommended limit of 1 mSv total for a pregnancy, and no more than 0.5 mSv per month. Information originally based on "Fundamentals of Aerospace Medicine" published in 2008.


title: Ionizing radiation

text: Hazardous levels of ionizing radiation are signified by the trefoil sign on a yellow background. These are usually posted at the boundary of a radiation controlled area or in any place where radiation levels are significantly above background due to human intervention.


title: Ionizing radiation

text: The red ionizing radiation warning symbol (ISO 21482) was launched in 2007, and is intended for IAEA Category 1, 2 and 3 sources defined as dangerous sources capable of death or serious injury, including food irradiators, teletherapy machines for cancer treatment and industrial radiography units. The symbol is to be placed on the device housing the source, as a warning not to dismantle the device or to get any closer. It will not be visible under normal use, only if someone attempts to disassemble the device. The symbol will not be located on building access doors, transportation packages or containers.


title: Percentile

text: In statistics, a "k"-th percentile (percentile score or centile) is a score "below which" a given percentage "k" of scores in its frequency distribution falls (exclusive definition) or a score "at or below which" a given percentage falls (inclusive definition).


title: Percentile

text: For example, the 50th percentile (the median) is the score below which 50% of the scores in the distribution are found (by the "exclusive" definition), or at or below which 50% of the scores are found (by the "inclusive" definition).


title: Percentile

text: Percentiles are expressed in the same unit of measurement as the input scores; for example, if the scores refer to human weight, the corresponding percentiles will be expressed in kilograms or pounds.


title: Percentile

text: The percentile score and the "percentile rank" are related terms. The percentile rank of a score is the percentage of scores in its distribution that are less than it, an exclusive definition, and one that can be expressed with a single, simple formula.


title: Percentile

text: Percentile scores and percentile ranks are often used in the reporting of test scores from norm-referenced tests, but, as just noted, they are not the same. For percentile rank, a score is given and a percentage is computed. Percentile ranks are exclusive. If the percentile rank for a specified score is 90%, then 90% of the scores were lower. In contrast, for percentiles a percentage is given and a corresponding score is determined, which can be either exclusive or inclusive. The score for a specified percentage (e.g., 90th) indicates a score below which (exclusive definition) or at or below which (inclusive definition) other scores in the distribution fall.


title: Percentile

text: The 25th percentile is also known as the first "quartile" ("Q"), the 50th percentile as the median or second quartile ("Q"), and the 75th percentile as the third quartile ("Q").


title: Percentile

text: When ISPs bill "burstable" internet bandwidth, the 95th or 98th percentile usually cuts off the top 5% or 2% of bandwidth peaks in each month, and then bills at the nearest rate. In this way, infrequent peaks are ignored, and the customer is charged in a fairer way. The reason this statistic is so useful in measuring data throughput is that it gives a very accurate picture of the cost of the bandwidth. The 95th percentile says that 95% of the time, the usage is below this amount: so, the remaining 5% of the time, the usage is above that amount.


title: Percentile

text: Physicians will often use infant and children's weight and height to assess their growth in comparison to national averages and percentiles which are found in growth charts.


title: Percentile

text: The 85th percentile speed of traffic on a road is often used as a guideline in setting speed limits and assessing whether such a limit is too high or low.


title: Percentile

text: In finance, value at risk is a standard measure to assess (in a model-dependent way) the quantity under which the value of the portfolio is not expected to sink within a given period of time and given a confidence value.


title: Percentile

text: The methods given in the "definitions section" (below) are approximations for use in small-sample statistics. In general terms, for very large populations following a normal distribution, percentiles may often be represented by reference to a normal curve plot. The normal distribution is plotted along an axis scaled to standard deviations, or sigma (formula_1) units. Mathematically, the normal distribution extends to negative infinity on the left and positive infinity on the right. Note, however, that only a very small proportion of individuals in a population will fall outside the −3"σ" to +3"σ" range. For example, with human heights very few people are above the +3"σ" height level.


title: Percentile

text: Percentiles represent the area under the normal curve, increasing from left to right. Each standard deviation represents a fixed percentile. Thus, rounding to two decimal places, −3"σ" is the 0.13th percentile, −2"σ" the 2.28th percentile, −1"σ" the 15.87th percentile, 0"σ" the 50th percentile (both the mean and median of the distribution), +1"σ" the 84.13th percentile, +2"σ" the 97.72nd percentile, and +3"σ" the 99.87th percentile. This is related to the 68–95–99.7 rule or the three-sigma rule. Note that in theory the 0th percentile falls at negative infinity and the 100th percentile at positive infinity, although in many practical applications, such as test results, natural lower and/or upper limits are enforced.


title: Percentile

text: however all definitions yield similar results when the number of observations is very large and the probability distribution is continuous. In the limit, as the sample size approaches infinity, the 100"p" percentile (0<"p"<1) approximates the inverse of the cumulative distribution function (CDF) thus formed, evaluated at "p", as "p" approximates the CDF. This can be seen as a consequence of the Glivenko–Cantelli theorem. Some methods for calculating the percentiles are given below.


title: Percentile

text: There are many formulas or algorithms for a percentile score. Hyndman and Fan identified nine and most statistical and spreadsheet software use one of the methods they describe. Algorithms either return the value of a score that exists in the set of scores (nearest-rank methods) or interpolate between existing scores and are either exclusive or inclusive.


title: Percentile

text: The figure shows a 10-score distribution, illustrates the percentile scores that result from these different algorithms, and serves as an introduction to the examples given subsequently. The simplest are nearest-rank methods that return a score from the distribution, although compared to interpolation methods, results can be a bit crude. The Nearest-Rank Methods table shows the computational steps for exclusive and inclusive methods.


title: Percentile

text: Interpolation methods, as the name implies, can return a score that is between scores in the distribution. Algorithms used by statistical programs typically use interpolation methods, for example, the percentile.exc and percentile.inc functions in Microsoft Excel. The Interpolated Methods table shows the computational steps.


title: Percentile

text: One definition of percentile, often given in texts, is that the "P"-th percentile formula_2 of a list of "N" ordered values (sorted from least to greatest) is the smallest value in the list such that no more than "P" percent of the data is strictly less than the value and at least "P" percent of the data is less than or equal to that value. This is obtained by first calculating the ordinal rank and then taking the value from the ordered list that corresponds to that rank. The ordinal rank "n" is calculated using this formula


title: Percentile

text: An alternative to rounding used in many applications is to use linear interpolation between adjacent ranks.


title: Percentile

text: we seek a linear interpolation function that passes through the points formula_5. This is simply accomplished by


title: Percentile

text: where formula_7 uses the floor function to represent the integral part of positive , whereas formula_8 uses the mod function to represent its fractional part (the remainder after division by 1). (Note that, though at the endpoint formula_9, formula_10 is undefined, it does not need to be because it is multiplied by formula_11.) As we can see, is the continuous version of the subscript , linearly interpolating between adjacent nodes.


title: Percentile

text: There are two ways in which the variant approaches differ. The first is in the linear relationship between the "rank" , the "percent rank" formula_12, and a constant that is a function of the sample size :


title: Percentile

text: There is the additional requirement that the midpoint of the range formula_14, corresponding to the median, occur at formula_15:


title: Percentile

text: The second way in which the variants differ is in the definition of the function near the margins of the formula_18 range of : formula_19 should produce, or be forced to produce, a result in the range formula_20, which may mean the absence of a one-to-one correspondence in the wider region. One author has suggested a choice of formula_21 where is the shape of the Generalized extreme value distribution which is the extreme value limit of the sampled distribution.


title: Percentile

text: Note that the formula_29 relationship is one-to-one for formula_30, the only one of the three variants with this property; hence the "INC" suffix, for "inclusive", on the Excel function.


title: Percentile

text: In addition to the percentile function, there is also a "weighted percentile", where the percentage in the total weight is counted instead of the total number. There is no standard function for a weighted percentile. One method extends the above approach in a natural way.


title: Percentile

text: Suppose we have positive weights formula_35 associated, respectively, with our "N" sorted sample values. Let


title: The Hound of the Baskervilles

text: The Hound of the Baskervilles is the third of the four crime novels by British writer Arthur Conan Doyle featuring the detective Sherlock Holmes. Originally serialised in "The Strand Magazine" from August 1901 to April 1902, it is set in 1889 largely on Dartmoor in Devon in England's West Country and tells the story of an attempted murder inspired by the legend of a fearsome, diabolical hound of supernatural origin. Holmes and Watson investigate the case. This was the first appearance of Holmes since his apparent death in "The Final Problem", and the success of "The Hound of the Baskervilles" led to the character's eventual revival.


title: The Hound of the Baskervilles

text: One of the most famous stories ever written, in 2003, the book was listed as number 128 of 200 on the BBC's The Big Read poll of the UK's "best-loved novel". In 1999, a poll of "Sherlockians" ranked it as the best of the four Holmes novels.


title: The Hound of the Baskervilles

text: Dr James Mortimer recounts to Sherlock Holmes in London an old legend of a curse that reportedly runs in the Baskerville family since the time of the English Civil War, when Sir Hugo Baskerville was killed by a huge demonic hound, with the same creature haunting the mires of Dartmoor ever since, causing the premature death of many Baskerville heirs. He reveals that his friend Sir Charles Baskerville, who took the legend of the hound seriously, was found dead in the yew alley of his estate, Baskerville Hall, in the midst of Dartmoor. The death was attributed to a heart attack, but Mortimer reveals that Sir Charles's face retained an expression of horror, and not far from his body were the footprints of a gigantic hound. Mortimer now fears for the next in line, Sir Henry Baskerville.


title: The Hound of the Baskervilles

text: Though he dismisses the curse as nonsense, Holmes agrees to meet Sir Henry, who is arriving from Canada, where he has been living. A young and jovial man, Sir Henry is sceptical about the legend and is eager to take possession of Baskerville Hall, in spite of receiving an anonymous note, warning him to stay away from the moor. When someone shadows Sir Henry while he is walking down a street, however, Holmes asks Watson to go with the Sir Henry and Mortimer to Dartmoor, in order to protect Sir Henry and search for any clues about who is following him.


title: The Hound of the Baskervilles

text: The trio arrive at Baskerville Hall. It has a married couple, the Barrymores, as butler and housekeeper. The estate is surrounded by the moor and borders the Grimpen Mire, where animals and humans can sink to death. The news that a convict named Selden, a murderer, has escaped from nearby Dartmoor Prison and is hiding in the nearby barren hills adds to the gloomy atmosphere.