document_title: Percy Jackson & the Olympians

question_text: what is the name of the 2nd percy jackson book

text: Percy Jackson & the Olympians

text: Origins[edit]

text: Development for both The Lightning Thief and the Percy Jackson series commenced when Rick Riordan began making stories for his son Haley Riordan, who had at the time been diagnosed with ADHD and dyslexia.[6] His son, Haley, had been studying Greek mythology in second grade and requested that his father tell him bedtime stories based on Greek myths. When Riordan ran out of myths, his son suggested that he make up new stories using existing mythological characters and new ones. This led Riordan to create the fictional character of Percy Jackson and create the story of how he travels across the United States to recover Zeus's lightning-bolt. Haley suggested that he should turn that story into a book, and Riordan wrote the book over the next year despite being busy at that time.[7]

text: Leaving his manuscript with his agent and editor for review, Riordan presented the book to a group of 6th, 7th, and 8th graders to read and critique. He gained their approval, and with their help, came up with the name of the book and created the way Percy's sword works.[8] In 2004, the book was sold to Miramax Books for enough money for Riordan to quit his job and focus on writing.[9] After it was released on 28 June 2005, it sold over 1.2 million copies. The book was released in multiple versions, including hardcover, paperback and audio editions.[10][11] It has been translated into multiple languages and published all over the world.[12]

text: Books[edit]

text: The Lightning Thief[edit]

text: The Lightning Thief is the first book in the series and was released on July 1, 2005.

text: After a harrowing experience at his school trip, Percy Jackson returns home for the summer vacation, wherein him and his mother Sally Jackson, travel to their cabin in Montauk to take their mind off things.However, the trip is cut short after a series of harrowing incidents, such as being attacked by the Minotaur. Percy finds himself at Camp Half-Blood, a training camp for demigods like him. He discovers that he is a demigod, son of Poseidon, the Greek god of the sea, earthquakes, and father of all horses, (which he made from sea foam). Percy also learns that his best friend, Grover Underwood, is actually a satyr, and that the Greek gods are accusing Percy of having stolen Zeus' master lightning bolt, the most powerful weapon in the world. To clear his name and save the world from another war between the Olympian gods, Percy sets out to retrieve the lightning bolt from Hades, who is suspected of being the real thief. Thus, Percy, Grover, and Annabeth Chase, a daughter of Athena, start on a journey to the underworld, facing numerous mythological monsters on the way. After confronting an innocent Hades, they learn that their friend Luke Castellan, son of Hermes, is the real thief who stole the bolt to allow Kronos, the defeated king of the Titans, a chance to rise again.

text: The book was adapted into a film by Chris Columbus and 20th Century Fox, under the title Percy Jackson & the Olympians: The Lightning Thief, and was released on February 12, 2010.

text: The Sea of Monsters[edit]

text: The Sea of Monsters is the second installment in the series, released on April 1, 2006.

text: Camp Half-Blood is under attack when Thalia's tree, which guards the borders of the camp, is poisoned and slowly begins to die. In order to save the tree and the camp, someone must recover the Golden Fleece, which is somewhere in the Sea of Monsters. At the same time, Percy finds out that Grover, who has left on a quest to find the missing god Pan, has been captured by the cyclops Polyphemus and that the Fleece is on Polyphemus' island. Together with Annabeth and his half-brother Tyson, a cyclops, Percy sets out to rescue Grover. Meanwhile, Clarisse La Rue, daughter of Ares, is sent on an official quest by Camp Half-Blood to retrieve the Fleece. The trip to the Sea of Monsters is long and hazardous and along the way the heroes encounter several dangers including Scylla and Charybdis, the sorceress Circe, the Sirens and their former friend Luke Castellan. Percy also learns about a prophecy from the Oracle about a child of one of the three most important gods (Zeus, Poseidon and Hades), playing a vital part in the success or failure of the resurrection of Kronos the Titan-King. The heroes eventually retrieve the Fleece and restore Thalia's tree but also unknowingly revive Thalia herself, daughter of Zeus, who had been turned into the tree by her father when she died.

text: The book was adapted into a film by Thor Freudenthal and 20th Century Fox, under the title Percy Jackson: Sea of Monsters, and was released on August 7, 2013.

text: The Titan's Curse[edit]

text: The Titan's Curse is the third installment in the series. It was released on May 11, 2007.[13]

text: On a mission to rescue half-bloods Bianca and Nico di Angelo; Percy, Annabeth, Thalia and Grover are attacked by a manticore and rescued by the goddess Artemis and her Hunters. However, Annabeth falls off a cliff whilst trying to fight the manticore and is said to be captured. Later, Artemis is captured by Luke's army while on the hunt for the Ophiotaurus, a cow-serpent monster that was foretold to bring the downfall of Olympus when its entrails are sacrificed to a fire. Her lieutenant Zoe Nightshade, daughter of Atlas, leads Bianca, Thalia and Grover on a quest to save her. Percy, who was not invited to join the party, follows them on behalf of Nico Di Angelo, promising that he will do his best to protect his sister, Bianca. The others eventually find Percy, and he joins their group. They become the prey of skeletons, who chase them across the country. Bianca is able to kill one, which leaves the others mystified. Bianca later dies as they make their way across a godly junkyard. They find Annabeth with Luke and Artemis, who is holding up the sky. Percy then takes it from Artemis and they trick Atlas into his original position under the sky. Thalia replaces Zoe, who dies, as Artemis' lieutenant. Thalia's induction as a lieutenant of Artemis ensures that she will become immortal, never aging to 16, thus escaping the Great Prophecy and leaving Percy to fulfill it. They return to camp and Percy informs Nico about Bianca's death during the journey. Nico blames Percy for failing to protect her and runs away, only after killing skeletons that invade the camp, so that Percy realizes that Hades is Nico's father.

text: The Battle of the Labyrinth[edit]

text: The Battle of the Labyrinth is the fourth installment in the series. It was released on May 6, 2008.

text: After being attacked by monsters, Percy returns to Camp Half-Blood and learns about the Labyrinth. Annabeth and Percy find an entrance into the Labyrinth in camp. Percy soon learns that Luke will use the entrance to lead his army through the Labyrinth straight into the heart of camp. Annabeth is chosen to lead a quest to prevent it, and chooses to bring Tyson, Percy, and Grover, even though it was traditional to bring only two companions on a quest, as explained by Chiron. While in the Labyrinth, Percy and Annabeth become separated from Grover and Tyson. They encounter Nico, who begins to forgive Percy. Percy and Annabeth arrive under Mount St. Helens. Percy accidentally causes St. Helens to erupt and washes ashore on Calypso's island, Ogygia. He returns to Camp Half-Blood, rather than staying with her, stating that "she would always be his biggest 'what-if'". Then he and Annabeth recruit a mortal girl, Rachel Dare to be a guide in the Labyrinth, using her sight through the Mist, the magical veil that separates the mythological world from the mortal world, and her knowledge for the quest. Daedalus is shown to be alive and to have given Ariadne's string to Luke. They find Grover and Tyson and discover Pan, and Grover tells him that he must return to the world. But Pan says that he cannot come and before dying tells Grover to tell those who will listen that he has died. Grover does what he is told. Percy also finds Luke's body in Kronos' coffin. A final demigod joins the Titans' cause, and Kronos fully rises, using Luke's body. They flee to camp, trying to stop the invasion. Kronos' forces attack the camp, but they are defeated. The book ends with Daedalus sacrificing himself after the battle to destroy the Labyrinth, as it is tied to his life force, and Nico Di Angelo fully forgiving Percy and proposing a dangerous plan for defeating the Titans.

text: The Last Olympian[edit]

text: The Last Olympian, the fifth and final book in the Percy Jackson series, was released on May 5, 2009.[14]

text: Percy Jackson learns that Kronos' forces are preparing to attack Olympus. Poseidon, Percy's father, decides that it is time for Percy to now fulfill the Great Prophecy. Seeking to defeat Kronos, like Achilles did, Percy bathes in the River Styx, making his body invulnerable except one small chosen part of his body (the small of his back). Kronos leads a siege of New York City and puts its citizens to sleep. Percy leads the campers, Hunters, nature spirits, and centaurs to protect Mount Olympus from Kronos and his forces. While they protect Olympus, the gods hold down the monster Typhon as he makes his way to New York. Kronos, possessing Luke's body, forces his way into Olympus and battles Percy in Olympus' throne room. Typhon reaches New York but is defeated after the arrival of Poseidon's forces, led by Tyson. Annabeth is able to make Luke come back to his senses, and Percy gives him Annabeth's knife. Luke stabs himself in his mortal spot (as he also was invulnerable from bathing in the River Styx) to destroy Kronos and save Mount Olympus, but Luke dies. The gods reward Percy and his friends, and offer him immortality. He rejects the offer, but instead requests the gods to claim all their children and to have cabins for all the gods, including the minor ones. Rachel Elizabeth Dare becomes the Oracle and recites the next Great Prophecy. The book finishes with Percy and Annabeth becoming a couple, and ominous clouds looming over Rachel's next Great Prophecy.

text: Supplementary works[edit]

text: The Demigod Files[edit]

text: The Demigod Files, also written by Rick Riordan, is the first companion book to the series. It was released February 10, 2009, featuring three short stories, interviews with the campers, puzzles and pictures.[15] It is set between The Battle of the Labyrinth and The Last Olympian.[16] The book received mixed reviews, with some reviewers criticizing the lack of substantial material and others commenting on the writing of the short stories. The stories are Percy Jackson and the Stolen Chariot, Percy Jackson and the Bronze Dragon, The Camper Interviews, and Percy Jackson and the Sword of Hades. At the end of the book, there are portraits on the characters of the series. [16]

text: The Ultimate Guide[edit]

text: The Ultimate Guide is a companion book, second to the series, released on January 19, 2010. This book has a magnetic cover and holographic character pictures that change into four different characters. Its 156 pages include trading cards, full-color diagrams and maps.[17] It also includes a dictionary of almost every monster Percy faces in the series, with pictures beside some, as well as various activities. The book tells of Percy Jackson's starting life as a half-blood, a tour of the Underworld by Nico di Angelo, the story of Sally Jackson's parents, and items used throughout the series. There is also a paperback version.

text: Graphic novels[edit]

text: A graphic novel based on The Lightning Thief was published on October 12, 2010. It follows a shortened version of Percy's adventures in The Lightning Thief with full color drawings. A graphic novel based on the second book in the series, The Sea of Monsters was released on July 2, 2013. Another graphic novel based on the third book, The Titan's Curse was released on October 8, 2013.[18]

text: Demigods and Monsters[edit]

text: Demigods and Monsters is an unofficial companion book and was released on February 11, 2009.[19] With an introduction by Riordan, it features essays written by various young adult authors that explore, discuss and provide further insight into the Percy Jackson series. At 196 pages, it also contains information on the places and characters of the series, as well as a glossary of Greek myths.[20]

text: The Demigod Diaries[edit]

text: The Demigod Diaries contains four new stories with character interviews, illustrations of characters and more, puzzles, and a quiz. The four stories include the adventures of Thalia, Luke, and Annabeth, and others which precede the Percy Jackson and the Olympians series and a first-person narrative from Percy's viewpoint. Set a month after the events of The Last Olympian and before he goes missing in The Lost Hero, Percy and Annabeth retrieve Hermes' stolen staff. One of the stories is written by Riordan's son, Haley, and revolves around one of the demigods who fought for Kronos during the Second Titan War and survived the battle in Manhattan. As a part of the spin-off The Heroes of Olympus series, The Demigod Diaries contain a story involving Jason, Leo, and Piper that recounts their time spent at Camp Half-Blood between The Lost Hero and The Son of Neptune.

text: Characters[edit]

text: Reception[edit]

text: The Lightning Thief received mostly positive reviews and won awards including the School Library Journal Best Book of 2005.[21] The New York Times praised The Lightning Thief as “perfectly paced, with electrifying moments chasing each other like heartbeats”.[22] Author Rick Riordan said of the various awards:

text: "The ultimate compliment for a children's writer is when the kids like it."[23]

text: Like its predecessor, The Sea of Monsters won several prizes and received generally positive reviews as well.[24][25] It sold over 100,000 copies in hardcover by the time it was released in paperback[26] and reviewers have praised the storyline, themes and the author's style of writing.[27][28][29] Matt Berman, of Common Sense Media, praised the book, saying “The Percy Jackson series continues to be pure fun, with the author doing nearly everything right to produce a book that few kids will be able to resist.”[28] Kirkus reviewed The Battle of the Labyrinth as, “This volume can stand alone, but no one will be able to read just one […] look no further for the next Harry Potter, meet Percy Jackson as legions of fans already have.” As of February 13, 2016, it has been on the New York Times Children's Series Best Seller List for 379 weeks.

text: Some critics, especially Christian critics of Riordan have disapproved of the emphasis on pagan gods in his books. Riordan responds to these complaints by reminding his readers that first and foremost,[30] "The Lightning Thief explores Greek mythology in a modern setting, but it does so as a humorous work of fantasy. I’m certainly not interested in changing or contradicting anyone’s religious beliefs. Early in the book, the character Chiron makes a distinction between God, capital-G, the creator of the universe, and the Greek gods (lower-case g). Chiron says he doesn’t want to delve into the issue of God, but he has no qualms about discussing the Olympians because they are a "much smaller matter."

text: Critics such as The Calico Critic have also disagreed with the fusion of Greek mythology and modern American culture. They have stated that it is difficult to believe "the reality of the tale", claiming that "monsters in the St. Louis Arch" and "the entrance to Olympus in New York" were unimaginable, despite Riordan's explanations of why he chose these certain locations.[31]

text: However studies show that overall, readers appreciated the mundane language, witty tone and aesthetic plot of the novels, as well as how it introduced Greek mythology to them.[31]

text: In other media[edit]

text: Films[edit]

text: These films have been made from the books:

text:
Percy Jackson & the Olympians: The Lightning Thief
Percy Jackson: Sea of Monsters

text: Chris Columbus directed and produced Percy Jackson & the Olympians: The Lightning Thief for 20th Century Fox through 1492 Pictures.[32][33] The film was released in 2010 in the United States, Canada and in the United Kingdom on February 12 and in Australia on February 11.[34] Columbus has stated that he was drawn to directing the Percy Jackson movie because it gave him the "opportunity to do a movie that we haven't really seen before for this generation. When I was a kid, there were movies that dealt with Greek mythology, which in terms of visual effects was really primitive. So I thought this was an opportunity to deal with Greek mythology which children and adults all over the world are fascinated by and it was not a new genre but a new avenue, dealing with mythological creatures in a contemporary setting."

text: The second film in the series, Percy Jackson: Sea of Monsters,[35][36] was released on August 7, 2013.[5] Filming began in April 2012.

text: Chris Columbus stated that there will not be a third movie any time soon.[citation needed]

text: Video game[edit]

text: To accompany the film, a video game was produced. Michael Splechta gave it a 6/10, saying Percy Jackson & the Olympians might not make a splash when it comes to movie tie-in games, but fans of turn-based combat might find some redeeming qualities in this otherwise bare-bones game."[37]

text: Musical[edit]

text: On January 12, 2017, A Series of Unfortunate Events story editor Joe Tracz wrote a new Off Broadway musical adaptation of Percy Jackson tale “The Lightning Thief.[38]

text: Legacy[edit]

text: Sequel series[edit]

text: The Heroes of Olympus[edit]

text: The Heroes of Olympus is a sequel series, also based on Camp Half-Blood and the Greek and Roman mythologies. The first book The Lost Hero was released on October 12, 2010. Like the first series, there are five books.[39] The official website requires a password, later revealed as newhero. On December 1, 2010, the site went live.[40]

text: The second book in The Heroes of Olympus, The Son of Neptune, was released in October 2011. The third book, The Mark of Athena, was released on October 2, 2012. The fourth book, The House of Hades, was released on October 8, 2013. The fifth and final book of The Heroes of Olympus series, The Blood of Olympus, was released on October 7, 2014.[41]

text: The Trials of Apollo[edit]

text: Riordan is currently at work on yet another follow-up series to The Heroes of Olympus book series titled The Trials of Apollo is a sequel series to both Percy Jackson & the Olympians and The Heroes of Olympus. The first installment titled, The Hidden Oracle (2016), features Apollo and his journey after being cast down from Olympus. The second book titled The Dark Prophecy was released in May 2017.The third book titled The Burning Maze was released on May 1, 2018.

text: Related series[edit]

text: The Kane Chronicles[edit]

text: The novels are set within the same fictional universe as the three previous book series, and is narrated alternately in first-person by the two protagonist-siblings Carter and Sadie Kane. The siblings are descended from the two pharaohs Narmer and Ramses the Great and are powerful magicians. They and their friends are forced to contend with Egyptian gods and goddesses who still interact with the real world. The series includes a trilogy consisting of The Red Pyramid (2010), The Throne of Fire (2011), and The Serpent's Shadow (2012), as well as three crossover books with the Percy Jackson & the Olympians series.

text: Magnus Chase and the Gods of Asgard[edit]

text: The main protagonist Magnus Chase, son of the Vanir god of fertility Frey, narrates the novel in first person. He is a cousin of Annabeth Chase, a main character of the Percy Jackson and the Olympians and The Heroes of Olympus series, who links the two series together.[42] The series consists of a trilogy of books, The Sword of Summer (2015), The Hammer of Thor (2016), and The Ship of the Dead (2017).


document_title: Feeding the multitude

question_text: where did the feeding of the five thousand take place

root

text: Feeding the multitude

text: The Feeding of the 5,000[edit]

text: The Feeding of the 5,000 is also known as the "miracle of the five loaves and two fish", because the Gospel of John reports that five barley loaves and two small fish supplied by a boy were used by Jesus to feed a multitude. According to Luke's Gospel, when Jesus heard that John the Baptist had been killed, he withdrew by boat privately to a solitary place near Bethsaida. The crowds followed Jesus on foot from the towns. When Jesus landed and saw a large crowd, he had compassion on them and healed their sick. As evening approached, the disciples came to him and said, "This is a remote place, and it's already getting late. Send the crowds away, so they can go to the villages and buy themselves some food."

tag: p

text: Jesus said they did not need to go away, and therefore the disciples were to give them something to eat. They said they only had five loaves of bread and two fish, which Jesus asked be brought to him. Jesus directed the people to sit down in groups on the grass. In Mark's Gospel the crowds sat in groups of 50 and 100,[1] and in Luke's Gospel, Jesus' instructions were to seat the crowd in groups of 50,[2] implying that there were 100 such groups.

text: Taking the five loaves and the two fish and looking up to heaven, he gave thanks and broke the loaves. Then he gave them to the disciples, and the disciples gave them to the people. They all ate and were satisfied, and the disciples picked up twelve baskets full of broken pieces that were left over. The number of those who ate was about five thousand men, beside women and children. In John's Gospel, the multitude has been attracted around Jesus because of the healing works he has performed, and the feeding of the multitude is taken as a further sign (Greek: σημεῖον) that Jesus is the Messiah, the prophet who (according to the promise in Deuteronomy 18:15) is to come into the world" (John 6:14).[3]

text: The Feeding of the 4,000[edit]

text: This story, which only appears in the Gospels of Mark and Matthew, is also known as the miracle of the seven loaves and fishes, as the Gospel of Matthew refers to seven loaves and a few small fish used by Jesus to feed a multitude.[4] According to the Gospels, a large crowd had gathered and was following Jesus. Jesus called his disciples to him and said:

text: "I have compassion for these people; they have already been with me three days and have nothing to eat. I do not want to send them away hungry, or they may collapse on the way."

text: His disciples answered:

text: "Where could we get enough bread in this remote place to feed such a crowd?"

text: "How many loaves do you have?" Jesus asked.

text: "Seven," they replied, "and a few small fish."

text: Some commentators note the differences between some of the details of the accounts as a means of emphasizing that there were two distinct miracles: for example, the baskets used for collecting the food which remained were twelve 'κοφινους' (hand baskets) in Mark 6:43 but seven 'σπυριδας' (large baskets) in Mark 8:8. Cornelius a Lapide stated that a 'σπυρίς' or 'large basket' was double the size of a 'κόφινος'.[5] An indication of the size of a 'σπυρίς' is that the apostle Paul was let out of a building through a gap in the Damascus city wall inside one, in order to avert a plot to kill him.[6]

text: In Mark 8:16-21 Jesus distinguishes the two miracles in a conversation with His apostles.


document_title: Simba

question_text: who did the voice for simba in lion king

text: Simba

text: Development[edit]

text: Conception[edit]

text:
Simba was framed for this terrible murder, and on the one hand you can say it wasn’t his fault, but he wasn’t a stand-up guy, so a little bit of the theme of the movie is you have to stand up for yourself if you know you’re right. So that idea of redemption, that idea of that day in your life that you have to take responsibility for yourself, that you’re no longer a child, you’re an adult, all those themes resonated with us when we were making the movie and, thankfully, the audience appreciated them, as well.

— Producer Don Hahn on Simba's role in the film.[1]

tag: div

text: The idea for The Lion King originated from Disney chairman Jeffrey Katzenberg in 1989[2] and was originally conceived under the title King of the Jungle.[3] The story, which has been compared to Bambi (1942),[4] was jokingly referred to as "Bambi in Africa" because of the similarities between the two films and their respective main characters.[5] Co-director Rob Minkoff said that both films are "more true-life adventure than mythical epic."[5] Though considered an original[6][7] coming-of-age[8] story that follows the life of Simba as he grows up and "tak[es] on the responsibility of adulthood," co-directors Roger Allers and Minkoff drew inspiration from other sources. In particular, the biblical figures Moses and Joseph served as creative inspiration for the character.[9] Producer Don Hahn said that, like them, Simba is "born into royalty, is then exiled, and has to return to claim [his] kingdom."[10]

text: Several film and entertainment critics have noted similarities and parallels between the stories of The Lion King and William Shakespeare's tragedy Hamlet, and their protagonists.[11][12][13][14] Allers said that these similarities were not initially intentional and came as a surprise to the filmmakers themselves; they noticed the similarities only after the story was established and they eventually decided to pursue it. According to Hahn, "When we first pitched the revised outline of the movie ... someone in the room announced that its themes and relationships were similar to Hamlet. Everyone responded favorably to the idea that we were doing something Shakespearean, so we continued to look for ways to model our film on that all-time classic."[10]

text: Screenwriter Jonathan Roberts said that, in a musical, songs are used to convey a character's emotions and "I wants." Composer Elton John and lyricist Tim Rice wrote the song "I Just Can't Wait to Be King" in order to give Simba a medium through which he can express his desire to become King of the Pride Lands. Roberts said, "It's a way for storytellers to move the story and deliver the direction of the character."[15]

text: Voice[edit]

text: Matthew Broderick provided the speaking voice of Adult Simba.[16] The first actor to be assigned to The Lion King,[7] Broderick learned of the role while he was on vacation in Ireland, where he received a telephone call from his agent informing him that the directors were interested in casting him as Simba.[17] At the time, Broderick was well known for portraying the title character in Ferris Bueller's Day Off (1986). The directors decided to cast him as Simba because they felt that he was "perfect" for the role; according to producer Don Hahn, Broderick's voice resembled "the kind of character who could be irresponsible and likeable, but you also felt that he could come back in a very heroic way."[18] Jonathan Taylor Thomas, who was starring as Randy Taylor on the television sitcom Home Improvement at the time,[19][20] was cast as the speaking voice of Young Simba.[21] His appearance and personality would later serve as creative inspiration for supervising animator Mark Henn.[6]

text: Though Broderick is a trained Broadway singer, he was not up to the task, and neither was non-singer Thomas, so Toto lead singer Joseph Williams and actor Jason Weaver were hired to dub their respective singing voices. Williams' voice is heard on the song "Can You Feel the Love Tonight".[22] Impressed by Weaver's performance as a young Michael Jackson in the miniseries The Jacksons: An American Dream, songwriters Elton John and Tim Rice recruited him to record "I Just Can't Wait to Be King" and "Hakuna Matata"[23] while the film was still in its early stages of production.[24] As directors, Roger Allers and Rob Minkoff worked closely with the actors in order to ensure credible performances.[25] As is frequently done in animated films, the filmmakers videotaped the actors while they recorded their dialogue, allowing the animators to incorporate their specific mannerisms into the designs of their characters.[26]

text: Characterization and animation[edit]

text: When The Lion King was green-lit, its concept and story were not well received by studio employees. To guarantee the release of at least one successful film, Disney CEO Jeffrey Katzenberg divided the studio into two separate projects: The Lion King and Pocahontas (1995), with Pocahontas expected to be the more successful of the two. Because of this assumption, the majority of the studio's more seasoned animators gravitated towards Pocahontas because The Lion King was deemed a "risk", while less experienced animators were assigned to work on The Lion King.[27] Co-director Rob Minkoff received this positively, saying that this decision "gave a lot of newer animators a chance to step up to leadership roles."[28]

text:
You can't just use your house cat as a model, thinking, "I can just draw him, only bigger." You need to know why a lion is a lion, the difference in movements between a lion, a tiger, a leopard or your house cat. We looked at this film as our Bambi. They had the same approach. Look at the way the deer are drawn in Snow White and the way they drew the deer in Bambi just a few years later. They look like real deer because the artists did their homework.

— Supervising animator Mark Henn on animating Simba.[29]

text: The role of animating Simba was divided between Mark Henn and Ruben A. Aquino. While Henn served as the supervising animator of Simba as a cub, credited as Young Simba,[30] Aquino was placed in charge of animating the character as he appears as an adult.[31] The Lion King was Disney's first animated feature film to feature absolutely no humans since Robin Hood (1973). According to Aquino, animating four-legged creatures is difficult because the artists are faced with the task of drawing "twice as many legs ... as you do with human characters" and must also attribute to them both human and animal-like qualities. For assistance, Aquino drew influence from previous animated films that feature four-legged creatures as their main characters, citing Bambi, Lady and the Tramp (1955) and The Jungle Book (1967) as his main sources of inspiration.[32]

text: Before The Lion King, Henn's experience as a supervising animator was limited to predominantly female characters;[4][33] he had just recently completed work on Ariel from The Little Mermaid (1989), Belle from Beauty and the Beast (1991) and Jasmine from Aladdin (1992).[29] When he became involved with The Lion King, Henn initially expressed interest in animating the film's villain, Scar, because he wanted to do "something different."[4] However, producer Don Hahn felt that he was better suited for animating Simba.[34] Henn approaches animating new characters by "put[ting himself] into the character’s situation." Simba proved to be a challenge because Henn was faced with the task of creating an animated character who would both appear and behave like a real lion cub. To achieve this, Henn visited zoos, sketched and studied live lion cubs that were brought into the studio for research, and frequently consulted with wildlife experts.[35]

text: When it came time to animate Simba during the "I Just Can't Wait to Be King" musical sequence, Henn felt it essential that the character remain on all fours at all times, despite the fact that he is meant to be dancing.[33] In terms of personality, Henn aimed to depict Simba as a "cocky, confident character" at the beginning of the film, who must eventually mature and learn to take responsibility.[4] The animators would often observe and document the voice actors while they recorded their dialogue, using their movements and mannerisms as a visual aid. Actor Jonathan Taylor Thomas, who provided the voice of Young Simba, served as inspiration for the design and personality of Simba. Henn said, "I loved watching Jonathan Taylor Thomas when he was a boy on Home Improvement, and getting to meet him and observe him."[36] Although Aquino was responsible for animating the majority of Simba's adult sequences, Henn animated the character's first appearance as an adult that occurs near the end of the "Hakuna Matata" musical number.[37]

text: Appearances[edit]

text: The Lion King[edit]

text: Released in theaters in 1994, The Lion King marks Simba's first appearance. All the animals in the Pride Lands gather at the foot of Pride Rock to commemorate the birth of Simba, who will eventually succeed to the throne and take his father Mufasa's place as king. Furious by the fact that he is no longer next in line, Simba's jealous uncle Scar refuses to attend the ceremony. While Simba grows into a rambunctious lion cub who frequently boasts about the fact that he will someday rule over the Pride Lands, Scar secretly plots against him.

text: Scar plots regicide and familicide against Simba and Mufasa by luring Simba into a vast gorge, where he triggers a wildebeest stampede. Notified by Scar that Simba is in danger, Mufasa rushes to his aid and manages to place him safely on a ledge. Weakened and unable to pull himself up the steep slope to safety, Mufasa asks his brother for assistance. However, Scar's true nature is revealed and he betrays Mufasa, throwing him into the gorge where he is killed by the fall.

text: Convinced by Scar that he is responsible for his father's death, Simba runs away to a distant jungle where he is befriended by Timon and Pumbaa, who teach him to ignore his past and avoid his responsibilities. There, he grows into a handsome young lion, while Scar wreaks havoc on the Pride Lands. When Simba is discovered by his childhood friend named Nala, she confronts him, warning him of Scar's tyranny and begging him to return home. Afraid of facing his past, Simba refuses until a wise mandrill named Rafiki leads him to Mufasa's ghost, who convinces him to return home and reclaim his kingdom from Scar.[38]

text: Simba returns to the Pride Lands and finds them barren because their natural resources have been squandered and abused by Scar. After witnessing Scar strike his mother Sarabi, Simba orders Scar to resign. At first thrown by the fact that he is alive, Scar soon regains composure and forces Simba to reveal that he is responsible for Mufasa's death, while cornering him at the edge of Pride Rock, hoping to subject him to a similar fate as his father. Having grown overconfident, Scar finally reveals to Simba that he killed Mufasa. Furious, Simba tackles Scar and forces him into announcing this to the pride, initiating a battle between Simba's pride of lionesses, Timon, Pumbaa and Scar's army of hyenas. Simba eventually defeats Scar and throws him into a pit, where he is cornered and killed by the hyenas, who overheard Scar blame them for what he'd done. Simba then takes his rightful place as king. When the kingdom returns to its former glory, the animals welcome the birth of King Simba and Queen Nala's first born.[39]

text: The Lion King II: Simba's Pride[edit]

text: A direct-to-video sequel released in 1998, Simba's Pride takes place shortly after the events of the first film, depicting Simba and Nala as king and queen of the Pride Lands. In a ceremony at Pride Rock, the Pride Lands commemorate the birth of Simba and Nala's daughter Kiara, whom Simba is overprotective of. He discovers that Kiara has disobeyed him by visiting the forbidden Outlands, home to an enemy pride of Scar's followers known as the Outsiders, and befriending a young member of the pride named Kovu. After a close confrontation with Kovu's mother Zira, the leader of the Outsiders and Scar's most loyal follower, Simba separates the two and reminds Kiara of her responsibilities as the future queen. Meanwhile, Zira plots to manipulate Kovu to exact revenge on Simba for Scar's death.

text: Several years later, Simba grants an adolescent Kiara's request to embark on her first hunt, but has Timon and Pumbaa follow her in secret. Realizing this, Kiara rebels and pursue her hunt outside of the Pride Lands, where she nearly falls victim to a wildfire. Kiara is rescued by Kovu, who returns her to the Pride Lands, which is actually part of Zira's plan to overthrow Simba. Saying that he has left the Outsiders, Kovu asks Simba to let him join his pride. Simba reluctantly accepts, but distrusts Kovu because of his similarities to Scar, and continues to treat him ruthlessly. That night, Simba has a nightmare about attempting to save his father Mufasa from falling into the stampede but is stopped by Scar who turns into Kovu and throws Simba off the cliff into the stampede.

text: While Kiara and Kovu's friendship continues to grow, Simba, encouraged by Nala, attempts to show Kovu kindness by spending a day with him. Realizing that Kovu is beginning to side with Simba because of his love for Kiara, Zira ambushes and attacks Simba. Convinced by Zira that Kovu is responsible for the ambush, Simba exiles him and forbids Kiara to see him, but she makes her father realize that he is acting irrationally, before leaving to find Kovu. When a battle ensues between the Pride Landers and the Outsiders, Kiara and Kovu arrive and stop them, with Kiara telling them that they are one. When a furious Zira attacks Simba, she is intercepted by Kiara, causing the two to fall over the edge of a cliff. Having landed safely on a ledge, Kiara offers to help Zira, who is struggling to hang on. However, Zira, consumed by her resentment towards Simba, falls to her death. Simba finally approves of Kiara's love for Kovu and reconciles with his daughter, and accepts the two lions as future king and queen of the Pride Lands.[40]

text: The Lion King 1½[edit]

text: In The Lion King 1½, a direct-to-video followup released in 2004, Simba appears as a less prominent character because the film's primary focus is on Timon and Pumbaa's behind-the-scenes role and involvement in The Lion King,[41][42] in which they appear as supporting characters. Although the two films technically share the same story and timeline, the plot of The Lion King 1½ focuses more on Timon and Pumbaa. The meerkat and warthog unknowingly coexist alongside Simba, and the story fills in the two characters' backstories and events that led up to their long-lasting friendship, coinciding with and often initiating the events that affect Simba's life during the first film. These events include the commemorative bow that occurs during the opening "Circle of Life" musical number and the collapsing of the animal tower that takes place during "I Just Can't Wait to Be King."[43] The film also explores, in further detail, the relationship among the three characters as Timon and Pumbaa struggle to raise Simba as adoptive "parents" and disapprove of his relationship with Nala, portraying Simba as he grows from an energetic young lion cub, into an incorrigible teenager and, finally, an independent young lion.[44]

text: Timon & Pumbaa and television[edit]

text: The success of The Lion King and popularity of its characters led to the production of Timon & Pumbaa, an animated television series starring Timon and Pumbaa. Simba makes several appearances, including one episode in which Timon drags him out to try to revive Pumbaa's lost memory.

text: In the episode "Congo On Like This," Timon and Pumbaa (especially Timon) suspect that Simba has reverted to his carnivorous nature. The episode "Shake Your Djibouti" again features Simba, when Timon and Pumbaa are forced to train him to protect them from a laboratory monster. Another episode, entitled "Rome Alone," shows Simba being captured by Romans and forced into gladiatorial battle with another lion named Claudius. Simba makes brief appearances in "Once Upon a Timon", "Zazu's Off-By-One Day", and "Beethoven's Whiff". He also appears in a music video of "The Lion Sleeps Tonight".

text: Simba was featured as a guest in the animated series House of Mouse, in which he alternates between cub and adult.

text: The Lion Guard[edit]

text: In November 2015, a new series called The Lion Guard was released. Set within the time gap in The Lion King II: Simba's Pride,[45] it features Kion who is the son and youngest child of Simba and Nala, who as the second-born cub, is tasked with assembling a team to protect the Pride Lands.[46]

text: Broadway musical[edit]

text: The success of The Lion King led to the production of a Broadway musical based on the film. Directed by Julie Taymor, with a book by Irene Mecchi and Roger Allers, The Lion King premiered at the New Amsterdam Theatre on November 13, 1997, where it ran for nine years until being moved to the Minskoff Theatre on June 13, 2006.[47] The role of Simba was originated by Scott Irby-Ranniar and Jason Raize, with Irby-Ranniar portraying Young Simba and Raize portraying Adult Simba.[48]

text: Raize auditioned for the role of Adult Simba after hearing that Taymor was looking to cast an actor who was of "unidentifiable ethnicity."[49] Raize revealed in an interview that there was a lot of competition for the role because the musical required "triple-threat work -- singing, dancing and acting -- that you don't get to such an extent in other shows. It was more the sense of who can take the challenge and not be daunted by the task." Raize, who instantly felt that he "had a connection with Simba," eventually won the role with the approval of Taymor and choreographer Garth Fagan,[50] with Fagan admiring the fact that Raize was "willing to try, to fail, and then to try again."[8] Once cast, Raize found it difficult to maintain Taymor's "sense of duality" because Simba is "both man and beast." He said, "The tendency is to sacrifice one for the other, but you can't."[51] Although hundreds of children auditioned for the role of Young Simba,[52] the casting process was far less grueling for Irby-Ranniar who, according to Taymor, simply "walked in and he had the part."[53]

text: Miscellaneous[edit]

text: Books[edit]

text: In 1994, a six-volume book set titled The Lion King: Six New Adventures were released. Set after the events of the first film, they featured a cub named Kopa, who was the son of Simba and Nala.

text: Merchandising and video games[edit]

text: As part of the franchise's merchandising, Simba has appeared in various The Lion King-related products.[54] The character's likeness has been used in and adapted into a variety of items, including plush toys and figurines, clothing, bedding, household decor and appliances.[55] The success of the Broadway musical has also led to its own line of merchandising,[56] including the Simba beanbag doll, based on the character's appearance and costume in the Broadway show.[57][58]

text: Since the film's 1994 debut, Simba has appeared as a playable character in a variety of video game releases, both directly and indirectly associated with the franchise. The character's first appearance as a video game character was in The Lion King, which was released by Virgin Interactive on November 1, 1994, for the video game platforms Super Nintendo Entertainment System, Sega Game Gear, Nintendo Entertainment System and PC.[59] The game follows the plot of the original film and features Simba as both a cub and an adult.[60]

text: On December 28, 2000,[61] Activision released The Lion King: Simba's Mighty Adventure for Game Boy Color and PlayStation.[62] The game encompasses 10 levels and incorporates the plot of both The Lion King and The Lion King II: Simba's Pride as "Simba ... matures from a precocious cub to an adult lion."[63] Simba also appears as a playable character in Disney Interactive Studios' Disney's Extreme Skate Adventure, released on September 3, 2003, for Game Boy Advance, PlayStation 2, GameCube and Xbox,[64] and Disney Friends , released for Nintendo DS on February 26, 2008.[65] Additionally, Simba appears in the Square Enix Kingdom Hearts video game franchise as a friend and ally of the series' main character, Sora.[66][67][68][69][70]

text: Walt Disney Parks and Resorts[edit]

text: Live versions of Simba appear in the Lion King musical and in the parades and shows at the Walt Disney Parks and Resorts.

text: Simba was also the main character in "Legend of the Lion King," a former Fantasyland attraction in Walt Disney World's Magic Kingdom, which retold the story of the film using fully articulated puppets. Other Disney attractions that have featured Simba include the Mickey's PhilharMagic 3D show and the Hong Kong Disneyland version of It's a Small World.

text: He appears as one of the main characters at Epcot's Land Pavilion 12-minute edutainment film Circle of Life: An Environmental Fable.

text: Reception and legacy[edit]

text: Critical response[edit]

text: Although The Lion King itself has garnered universal acclaim from film critics,[71] reception towards Simba has been generally mixed. The Christian Science Monitor's David Sterritt hailed Simba as "a superbly realized character," specifically praising the scene in which the character "faces discipline by his dad after his adventure with the hyenas."[72] Owen Gleiberman of Entertainment Weekly wrote that Simba "has been given a marvelously expressive face" to the point of which "He seems more human than the Ken and Barbie types featured in Aladdin and The Little Mermaid."[73] Peter Travers of Rolling Stone described "the father-son relationship" shared by Simba and Mufasa as "movingly rendered,"[74] while About.com's David Nusair wrote, "it’s the touching father/son stuff that lies at the heart of the movie that cements The Lion King's place as an utterly timeless piece of work."[75] James Berardinelli of ReelViews enjoyed the fact that the film focuses more on the story of Simba himself as opposed to the romantic relationship developing between the character and Nala. However, Berardinelli criticized Matthew Broderick's vocal performance, describing it as "nondescript."[76] Rob Humanick of Slant Magazine hailed the fact that "it's never laid on [Simba] that his time as king will directly correspond with the eventual passing of his father" as one of the film's "most important facets." However, he criticized The Lion King's characters, describing them as well-designed but "lazy and troublesome."[77] The Austin Chronicle's Robert Faires felt that Simba and the other Lion King characters, though "true", were simply unoriginal retreads of preceding animated characters who were "swiped from other Disney cartoons."[78]

text: Hal Hinson of The Washington Post gave the character a negative review. Labeling Timon and Pumbaa the only interesting characters in The Lion King, Hinson questioned Simba's role as the film's hero.[79] Kenneth Turan of the Los Angeles Times agreed, "A movie's heroes may have their names above the title, but often as not it's the sidekicks who get the real work done." Turan went on to pan Simba, describing him as "irritatingly callow."[80] Chris Hick of the Deseret News complained about the fact that Simba and the other "characters in The Lion King are not as warm and fuzzy as other Disney animated features," crediting this with making "the film a bit tougher to warm [up] to."[81] ComingSoon.net strongly panned Simba as a lead character, writing, "typically for Disney animated fare, it's the hero who is the weak link being both blandly designed and blandly performed."[82] Acknowledging the character's Shakespearean origins, The Baltimore Sun's Stephen Hunter gave Simba a negative review, writing, "Alas ...Simba stands in for Hamlet, but he's a lot less complicated; in fact, he's less complicated than Morris the Cat or Sylvester." Hunter continued, "Simba the Exile is even less interesting than Simba the Prince."[83] Christopher Null of Contactmusic.com was critical of Weaver's performance as the singing voice of Young Simba, writing, "If there's anything annoying about the film, it's the singing. Young Simba sounds like a young Michael Jackson ... You almost don't want him to succeed." However, Null reacted more positively towards Broderick's performance.[84]

text: Despite the character's mixed reception, several critics have awarded specific praise to Broderick for his portrayal of Simba, including the San Francisco Chronicle's Peter Stack and The Washington Post's Desson Howe.[85][86] Annette Basile of Filmink described Broderick's performance as "excellent,"[87] while Peter Bradshaw of The Guardian called it "sumptuous." Digital Spy's Mayer Nissim described Broderick's portrayal of Simba as "wonderful."[88]

text: Impact and popularity[edit]

text: During the film's opening number, "Circle of Life", Rafiki introduces a newborn Simba to the crowd of animals gathered at the foot of Pride Rock by holding him high above their heads while parents Mufasa and Sarabi look on.[9] Since the film's 1994 release, this scene has grown to iconic status.[89] In November 2002, singer Michael Jackson sparked controversy by holding his son over the protective railing of a hotel balcony in Berlin. The event was witnessed by a large crowd of spectators who were watching from below.[90] Some sources have claimed that Jackson was harmlessly attempting to emulate the scene from The Lion King.[91]

text: When Kate Middleton, Duchess of Cambridge went into labor with hers and Prince William's baby in July 2013, the idea that the couple should reenact the famous scene from The Lion King became quite popular among Twitter users.[92][93] Radio journalist Darren Simpson reportedly tweeted, "when your baby arrives please re-enact the scene from the Lion King".[94] Shortly after Middleton gave birth to a boy, England native Tommy Peto initiated a petition asking the couple to welcome their baby by having the Archbishop of Canterbury emulate the scene by holding him over the balcony of Buckingham Palace. Ultimately, the idea was deemed "outside the responsibility of the government" and was declined.[95]

text: The scene has found itself the subject of both reference and parody in various forms of media, such as in the film George of the Jungle (1997).[96] In what is almost an exact replica of the scene, George, portrayed by actor Brendan Fraser, takes the place of both Rafiki and Mufasa by standing at the tip of Pride Rock and presenting his young son to a crowd of onlooking animals, accompanied by wife Ursula, portrayed by Leslie Mann.[97]

text: During the third season finale of Once Upon a Time, the main character Emma Swan asked her parents Snow White and David Nolan if they were going to hold up her yet unnamed baby brother like in The Lion King.[98] Since the release of The Lion King in 1994, the name "Simba" has increased in use and popularity among dog and cat owners. According to Comcast in 2010, the use of Simba as a dog name reemerged in popularity in 2009 after experiencing a noticeable decline in 2001, ranking the name ninth out of 10 on its list of "Top 10 Trendiest Dog Names of the Year."[99] In May 2013, Yahoo! Lifestyle included the name on its list of "Trendiest Dog Names."[100] According to YouPet, Simba is the 17th most popular cat name out of 100 candidates.[101] Care2 included Simba in its article "All-around Cool Cat Names,"[102] while DutchNews.nl reported that Simba ranks among the country's most popular cat names as of July 2013.[103] In its list of "Top Popular Pet Names," BabyNames.com placed Simba at number 64 on its list of most popular dog names out of the 100 that were considered.[104]


document_title: Production function

question_text: functions of capital as a factor of production

text: Production function

text: The theory of production functions[edit]

text: In general, economic output is not a (mathematical) function of input, because any given set of inputs can be used to produce a range of outputs. To satisfy the mathematical definition of a function, a production function is customarily assumed to specify the maximum output obtainable from a given set of inputs.  The production function, therefore, describes a boundary or frontier representing the limit of output obtainable from each feasible combination of input. (Alternatively, a production function can be defined as the specification of the minimum input requirements needed to produce designated quantities of output.) Assuming that maximum output is obtained from given inputs allows economists to abstract away from technological and managerial problems associated with realizing such a technical maximum, and to focus exclusively on the problem of allocative efficiency, associated with the economic choice of how much of a factor input to use, or the degree to which one factor may be substituted for another. In the production function itself, the relationship of output to inputs is non-monetary; that is, a production function relates physical inputs to physical outputs, and prices and costs are not reflected in the function.

text: In the decision frame of a firm making economic choices regarding production—how much of each factor input to use to produce how much output—and facing market prices for output and inputs, the production function represents the possibilities afforded by an exogenous technology. Under certain assumptions, the production function can be used to derive a marginal product for each factor. The profit-maximizing firm in perfect competition (taking output and input prices as given) will choose to add input right up to the point where the marginal cost of additional input matches the marginal product in additional output. This implies an ideal division of the income generated from output into an income due to each input factor of production, equal to the marginal product of each input.

text: The inputs to the production function are commonly termed factors of production and may represent primary factors, which are stocks.  Classically, the primary factors of production were Land, Labour and Capital. Primary factors do not become part of the output product, nor are the primary factors, themselves, transformed in the production process.  The production function, as a theoretical construct, may be abstracting away from the secondary factors and intermediate products consumed in a production process. The production function is not a full model of the production process: it deliberately abstracts from inherent aspects of physical production processes that some would argue are essential, including error, entropy or waste, and the consumption of energy or the co-production of pollution. Moreover, production functions do not ordinarily model the business processes, either, ignoring the role of strategic and operational business management. (For a primer on the fundamental elements of microeconomic production theory, see production theory basics).

text: The production function is central to the marginalist focus of neoclassical economics, its definition of efficiency as allocative efficiency, its analysis of how market prices can govern the achievement of allocative efficiency in a decentralized economy, and an analysis of the distribution of income, which attributes factor income to the marginal product of factor input.

text: Specifying the production function[edit]

text: A production function can be expressed in  a functional form as the right side of

text:
where

Q

{\displaystyle Q}

 is the quantity of output and

X

1

,

X

2

,

X

3

,
…
,

X

n

{\displaystyle X_{1},X_{2},X_{3},\dotsc ,X_{n}}

 are the quantities of factor inputs (such as capital, labour, land or raw materials).

text:
If

Q

{\displaystyle Q}

 is a scalar, then this form does not encompass joint production, which is a production process that has multiple co-products. On the other hand, if

f

{\displaystyle f}

 maps from

R

n

{\displaystyle \mathbb {R} ^{n}}

 to

R

k

{\displaystyle \mathbb {R} ^{k}}

 then it is a joint production function expressing the determination of

k

{\displaystyle k}

 different types of output based on the joint usage of the specified quantities of the

n

{\displaystyle n}

 inputs.

text: One formulation, unlikely to be relevant in practice, is as a linear function:

text:
where

a

0

,
…
,

a

n

{\displaystyle a_{0},\dots ,a_{n}}

 are parameters that are determined empirically.
Another is as a Cobb–Douglas production function:

text: The Leontief production function applies to situations in which inputs must be used in fixed proportions; starting from those proportions, if usage of one input is increased without another being increased, output will not change. This production function is given by

text:
Other forms include the constant elasticity of substitution production function (CES), which is a generalized form of the Cobb–Douglas function, and the quadratic production function. The best form of the equation to use and the values of the parameters (

a

0

,
…
,

a

n

{\displaystyle a_{0},\dots ,a_{n}}

) vary from company to company and industry to industry. In a short run production function at least one of the

X

{\displaystyle X}

's (inputs) is fixed. In the long run all factor inputs are variable at the discretion of management.

text: Moysan and Senouci (2016) provide an analytical formula for all 2-input, neoclassical production functions.[3]

text: Production function as a graph[edit]

text: Any of these equations can be plotted on a graph. A typical (quadratic) production function is shown in the following diagram under the assumption of a single variable input (or fixed ratios of inputs so they can be treated as a single variable). All points above the production function are unobtainable with current technology, all points below are technically feasible, and all points on the function show the maximum quantity of output obtainable at the specified level of usage of the input. From point A to point C, the firm is experiencing positive but decreasing marginal returns to the variable input. As additional units of the input are employed, output increases but at a decreasing rate. Point B is the point beyond which there are diminishing average returns, as shown by the declining slope of the average physical product curve (APP) beyond point Y. Point B is just tangent to the steepest ray from the origin hence the average physical product is at a maximum. Beyond point B, mathematical necessity requires that the marginal curve must be below the average curve (See production theory basics for further explanation.).

text: Stages of production[edit]

text: To simplify the interpretation of a production function, it is common to divide its range into 3 stages. In Stage 1 (from the origin to point B) the variable input is being used with increasing output per unit, the latter reaching a maximum at point B (since the average physical product is at its maximum at that point). Because the output per unit of the variable input is improving throughout stage 1, a price-taking firm will always operate beyond this stage.

text:
In Stage 2, output increases at a decreasing rate, and the average and marginal physical product both decline. However, the average product of fixed inputs (not shown) is still rising, because output is rising while fixed input usage is constant. In this stage, the employment of additional variable inputs increases the output per unit of fixed input but decreases the output per unit of the variable input. The optimum input/output combination for the price-taking firm will be in stage 2, although a firm facing a downward-sloped demand curve might find it most profitable to operate in Stage 1.
In Stage 3, too much variable input is being used relative to the available fixed inputs: variable inputs are over-utilized in the sense that their presence on the margin obstructs the production process rather than enhancing it. The output per unit of both the fixed and the variable input declines throughout this stage. At the boundary between stage 2 and stage 3, the highest possible output is being obtained from the fixed input.

text: Shifting a production function[edit]

text: By definition, in the long run the firm can change its scale of operations by adjusting the level of inputs that are fixed in the short run, thereby shifting the production function upward as plotted against the variable input. If fixed inputs are lumpy, adjustments to the scale of operations may be more significant than what is required to merely balance production capacity with demand. For example, you may only need to increase production by  million units per year to keep up with demand, but the production equipment upgrades that are available may involve increasing productive capacity by 2 million units per year.

text: If a firm is operating at a profit-maximizing level in stage one, it might, in the long run, choose to reduce its scale of operations (by selling capital equipment). By reducing the amount of fixed capital inputs, the production function will shift down. The beginning of stage 2 shifts from B1 to B2. The (unchanged) profit-maximizing output level will now be in stage 2.

text: Homogeneous and homothetic production functions[edit]

text:
There are two special classes of production functions that are often analyzed. The production function

Q
=
f
(

X

1

,

X

2

,
…
,

X

n

)

{\displaystyle Q=f(X_{1},X_{2},\dotsc ,X_{n})}

 is said to be homogeneous of degree

m

{\displaystyle m}

, if given any positive constant

k

{\displaystyle k}

,

f
(
k

X

1

,
k

X

2

,
…
,
k

X

n

)
=

k

m

f
(

X

1

,

X

2

,
…
,

X

n

)

{\displaystyle f(kX_{1},kX_{2},\dotsc ,kX_{n})=k^{m}f(X_{1},X_{2},\dotsc ,X_{n})}

. If

m
>
1

{\displaystyle m>1}

, the function exhibits increasing returns to scale, and it exhibits decreasing returns to scale if

m
<
1

{\displaystyle m<1}

. If it is homogeneous of degree

1

{\displaystyle 1}

, it exhibits constant returns to scale. The presence of increasing returns means that a one percent increase in the usage levels of all inputs would result in a greater than one percent increase in output; the presence of decreasing returns means that it would result in a less than one percent increase in output. Constant returns to scale is the in-between case. In the Cobb–Douglas production function referred to above, returns to scale are increasing if

a

1

+

a

2

+
⋯
+

a

n

>
1

{\displaystyle a_{1}+a_{2}+\dotsb +a_{n}>1}

, decreasing if

a

1

+

a

2

+
⋯
+

a

n

<
1

{\displaystyle a_{1}+a_{2}+\dotsb +a_{n}<1}

, and constant if

a

1

+

a

2

+
⋯
+

a

n

=
1

{\displaystyle a_{1}+a_{2}+\dotsb +a_{n}=1}

.

text: If a production function is homogeneous of degree one, it is sometimes called "linearly homogeneous". A linearly homogeneous production function with inputs capital and labour has the properties that the marginal and average physical products of both capital and labour can be expressed as functions of the capital-labour ratio alone. Moreover, in this case if each input is paid at a rate equal to its marginal product, the firm's revenues will be exactly exhausted and there will be no excess economic profit.[4]:pp.412–414

text:
Homothetic functions are functions whose marginal technical rate of substitution (the slope of the isoquant, a curve drawn through the set of points in say labour-capital space at which the same quantity of output is produced for varying combinations of the inputs) is homogeneous of degree zero. Due to this, along rays coming from the origin, the slopes of the isoquants will be the same. Homothetic functions are of the form

F
(
h
(

X

1

,

X

2

)
)

{\displaystyle F(h(X_{1},X_{2}))}

 where

F
(
y
)

{\displaystyle F(y)}

 is a monotonically increasing function (the derivative of

F
(
y
)

{\displaystyle F(y)}

 is positive (

d

F

/

d

y
>
0

{\displaystyle \mathrm {d} F/\mathrm {d} y>0}

)), and the function

h
(

X

1

,

X

2

)

{\displaystyle h(X_{1},X_{2})}

 is a homogeneous function of any degree.

text: Aggregate production functions[edit]

text: In macroeconomics, aggregate production functions for whole nations are sometimes constructed. In theory they are the summation of all the production functions of individual producers; however there are methodological problems associated with aggregate production functions, and economists have debated extensively whether the concept is valid.[2]

text: Criticisms of the production function theory[edit]

text: There are two major criticisms[which?] of the standard form of the production function.[5]

text: On the concept of capital[edit]

text: During the 1950s, '60s, and '70s there was a lively debate about the theoretical soundness of production functions (see the Capital controversy). Although the criticism was directed primarily at aggregate production functions, microeconomic production functions were also put under scrutiny. The debate began in 1953 when Joan Robinson criticized the way the factor input capital was measured and how the notion of factor proportions had distracted economists. She wrote:

text: "The production function has been a powerful instrument of miseducation. The student of economic theory is taught to write Q = f (L, K ) where L is a quantity of labor, K a quantity of capital and Q a rate of output of commodities. [They] are instructed to assume all workers alike, and to measure L in man-hours of labor; [they] are told something about the index-number problem in choosing a unit of output; and then [they] are hurried on to the next question, in the hope that [they] will forget to ask in what units K is measured. Before [they] ever do ask, [they] have become a professor, and so sloppy habits of thought are handed on from one generation to the next".[6]

text: According to the argument, it is impossible to conceive of capital in such a way that its quantity is independent of the rates of interest and wages. The problem is that this independence is a precondition of constructing an isoquant. Further, the slope of the isoquant helps determine relative factor prices, but the curve cannot be constructed (and its slope measured) unless the prices are known beforehand.

text: On the empirical relevance[edit]

text: As a result of the criticism on their weak theoretical grounds, it has been claimed that empirical results firmly support the use of neoclassical well behaved aggregate production functions. Nevertheless, Anwar Shaikh  has demonstrated that they also have no empirical relevance, as long as alleged good fit outcomes from an accounting identity, not from any underlying laws of production/distribution.[7]

text: Natural resources[edit]

text: Natural resources are usually absent in production functions. When Robert Solow and Joseph Stiglitz attempted to develop a more realistic production function by including natural resources, they did it in a manner economist Nicholas Georgescu-Roegen criticized as a "conjuring trick": Solow and Stiglitz had failed to take into account the laws of thermodynamics, since their variant allowed man-made capital to be a complete substitute for natural resources. Neither Solow nor Stiglitz reacted to Georgescu-Roegen's criticism, despite an invitation to do so in the September 1997 issue of the journal Ecological Economics.[1] [8]:127-136 [2] [9]

text: The practice of production functions[edit]

text: The theory of production function depicts the relation between physical outputs of a production process and physical inputs, i.e. factors of production. The practical application of production function is obtained by valuing the physical outputs and inputs by their prices. The economic value of physical outputs minus the economic value of physical inputs is the income generated by the production process. By keeping the prices fixed between two periods under review we get the income change generated by the change of production function. This is the principle how the production function is made a practical concept, i.e. measureable and understandable in practical situations.


document_title: First interracial kiss on television

question_text: who had the first interracial kiss on tv

text: First interracial kiss on television

text: Claims[edit]

text: UK television[edit]

text: You in Your Small Corner 1962, and Hot Summer Night 1959[edit]

text: In June 1962, a live performance of the play You in Your Small Corner by Barry Reckord was broadcast on British television as part of the series Granada Play of the Week. The central theme of the play is a relationship between a young black intellectual and a white working class girl. During the play, a kiss takes place between actors Lloyd Reckord and Elizabeth MacLennan, and what has been described as an "explicit post-coital scene".[1]

text: You In Your Small Corner was rediscovered during preparations for a November 2015 British Film Institute panel discussion on "Race and Romance on TV" and was used in publicity for the event. As a result, panel moderator Samira Ahmed was able, on the night, to announce the rediscovery of an even earlier TV kiss by Lloyd Reckord, with Andrée Melly, in the ITV Armchair Theatre adaptation of Ted Willis's play Hot Summer Night, broadcast on 1 February 1959.[2][3]

text: Emergency Ward 10[edit]

text: One of the earliest interracial kisses on television occurred in a July 1964 episode of British soap opera Emergency Ward 10, during which characters Louise Mahler (portrayed by Joan Hooley) and Giles Farmer (portrayed by John White) kissed.[1][4][5] The scene in which Mahler and Farmer kissed was originally scripted to occur in Mahler's bedroom, but was rewritten so as to occur outdoors, due to concerns it would otherwise be too risqué (the earlier Lloyd Reckord plays had both been shown well after the 9pm adult-content watershed). According to an issue of the Daily Express published after the episode aired, "not a viewer rang-up to complain".[6] In a 2015 interview, conducted prior to the discovery of the You in Your Small Corner footage, Hooley noted that the historic importance of what had been known as the "first interracial kiss on television" had been inflated in popular memory:

text: A lot of people spoke about it more ten years later than they did at the time it was happening. So, it was much later that it occurred to me that I was part of history. I find it odd to have to admit that I was part of history because I don't see why there should be anything to do about it. I don't think there should have been all this fuss about it.

text: US television[edit]

text: I Love Lucy[edit]

text: The 1950s American television programme I Love Lucy broadcast multiple instances of real-life husband and wife Desi Arnaz, a Hispanic male, and Lucille Ball, a woman of North European ancestry, kissing.[7] However, despite Arnaz and Ball being frequently described as an "interracial couple", "Hispanic" is generally understood to be a catchall indicating persons of a Latin American, Iberian, or Filipino cultural background, as opposed to a race. Arnaz was usually considered to be a white male of Cuban ancestry.[8]

text: I Spy[edit]

text: A January 5, 1966 episode of I Spy titled "The Tiger"[9] featured a scripted interracial kiss between Eurasian actress France Nuyen and Robert Culp almost two years before "Plato's Stepchildren".[10]

text: Movin' with Nancy[edit]

text: A December 1967 episode of Movin' with Nancy featured a kiss between Nancy Sinatra and Sammy Davis, Jr., more than a year before the Star Trek episode "Plato's Stepchildren" aired.[11]

text: Star Trek[edit]

text: A 1968 episode of Star Trek, "Plato's Stepchildren",[1][12] which first aired on November 22, 1968, is often referred to as the first interracial kiss on American television. This claim is disputed by some who contend that in the scene in question, full lip contact between William Shatner and Nichelle Nichols did not occur, as the actors turned their heads away from the camera at the last moment to present the illusion of a kiss, meaning that this scene was not a true kiss.[13] The latter point has been disputed, with Shatner claiming that he and Nichols' lips never fully touched and Nichols asserting that the kiss was real.[14]

text: It is often ignored that "Mirror, Mirror", which originally aired on October 6, 1967, featured a scripted interracial kiss between Eurasian actress Barbara Luna and the aforementioned William Shatner a year prior.[15]


document_title: Rh blood group system

question_text: where does a rhesus negative blood come from

text: Rh blood group system

text: History of discoveries[edit]

text: The first rhesus blood type was discovered in 1937 by Landsteiner and Wiener, who named it after a similar factor found in rhesus monkey blood.  The significance of the discovery was not immediately apparent and was only realized in 1940, after subsequent findings by Philip Levine and Rufus Stetson.[2]  The serum that led to the discovery was produced by immunizing rabbits with red blood cells from a rhesus macaque. The antigen that induced this immunization was designated by them as Rh factor to indicate that rhesus blood had been used for the production of the serum.[3]

text: In 1939, Phillip Levine and Rufus Stetson published in a first case report the clinical consequences of non-recognized Rh factor, hemolytic transfusion reaction, and hemolytic disease of the newborn in its most severe form.[4] It was recognized that the serum of the reported woman agglutinated with red blood cells of about 80% of the people although the then known blood groups, in particular ABO were matched. No name was given to this agglutinin when described. In 1940, Karl Landsteiner and Alexander S. Wiener made the connection to their earlier discovery, reporting a serum that also reacted with about 85% of different human red blood cells.[5]

text: In 1941, Group O: a patient of Dr. Paul in Irvington, NJ, delivered a normal infant in 1931[6]: this pregnancy was followed by a long period of sterility. The second pregnancy (April, 1941) resulted in an infant suffering icterus gravis.[7] In May 1941, the third anti-Rh serum (M.S.) of Group O became available. [8]

text: Based on the serologic similarities,  Rh factor was later also used for antigens, and anti-Rh for antibodies, found in humans such as those previously described by Levine and Stetson. Although differences between these two sera were shown already in 1942 and clearly demonstrated in 1963, the already widely used term "Rh" was kept for the clinically described human antibodies which are different from the ones related to the rhesus monkey. This real factor found in rhesus macaque was classified in the Landsteiner-Wiener antigen system (antigen LW, antibody anti-LW) in honor of the discoverers.[9][10]

text: It was recognized that the Rh factor was just one in a system of various antigens. Based on different models of genetic inheritance, two different terminologies were developed; both of them are still in use.

text: The clinical significance of this highly immunizing D antigen (i.e., Rh factor) was soon realized. Some keystones were to recognize its importance for blood transfusion (including reliable diagnostic tests), hemolytic disease of the newborn (including exchange transfusion), and very importantly the prevention of it by screening and prophylaxis.

text: The discovery of fetal cell-free DNA in maternal circulation by Holzgrieve et al. led to the noninvasive genotyping of fetal Rh genes in many countries.

text: Rh nomenclature[edit]

text:
Rh haplotype notation

Fisher-Race
Wiener

Dce
R0

DCe
R1

DcE
R2

DCE
RZ

dce
r

dCe
r′

dcE
r″

dCE
rY

tag: table

text: The Rh blood group system has two sets of nomenclatures: one developed by Ronald Fisher and R.R. Race, the other by Wiener. Both systems reflected alternative theories of inheritance. The Fisher-Race system, which is more commonly in use today, uses the CDE nomenclature. This system was based on the theory that a separate gene controls the product of each corresponding antigen (e.g., a "D gene" produces D antigen, and so on). However, the d gene was hypothetical, not actual.

text: The Wiener system used the Rh–Hr nomenclature. This system was based on the theory that there was one gene at a single locus on each chromosome, each contributing to production of multiple antigens. In this theory, a gene R1 is supposed to give rise to the “blood factors” Rh0, rh′, and rh″ (corresponding to modern nomenclature of the D, C, and E antigens) and the gene r to produce hr′ and hr″ (corresponding to modern nomenclature of the c and e antigens).[11]

text: Notations of the two theories are used interchangeably in blood banking (e.g., Rho(D) meaning RhD positive). Wiener’s notation is more complex and cumbersome for routine use. Because it is simpler to explain, the Fisher-Race theory has become more widely used.

text: DNA testing has shown that both are partially correct.[citation needed] There are in fact two linked genes, the RHD gene which produces a single immune specificity (anti-D) and the RHCE gene with multiple specificities (anti-C, anti-c, anti-E, anti-e). Thus, Wiener’s postulate that a gene could have multiple specificities (something many did not give credence to originally) has been proven correct. On the other hand, Wiener’s theory that there is only one gene has proven incorrect, as has the Fischer-Race theory that there are three genes, rather than the 2. The CDE notation used in the Fisher-Race nomenclature is sometimes rearranged to DCE to more accurately represent the co-location of the C and E encoding on the RhCE gene, and to make interpretation easier.

text: Rh system antigens[edit]

text: The proteins which carry the Rh antigens are transmembrane proteins, whose structure suggest that they are ion channels.[12] The main antigens are D, C, E, c and e, which are encoded by two adjacent gene loci, the RHD gene which encodes the RhD protein with the D antigen (and variants)[13] and the RHCE gene which encodes the RhCE protein with the C, E, c and e antigens (and variants).[14] There is no d antigen. Lowercase "d" indicates the absence of the D antigen (the gene is usually deleted or otherwise nonfunctional).

text: Rh phenotypes are readily identified through the presence or absence of the Rh surface antigens. As can be seen in the table below, most of the Rh phenotypes can be produced by several different Rh genotypes. The exact genotype of any individual can only be identified by DNA analysis. Regarding patient treatment, only the phenotype is usually of any clinical significance to ensure a patient is not exposed to an antigen they are likely to develop antibodies against. A probable genotype may be speculated on, based on the statistical distributions of genotypes in the patient’s place of origin.

text: R0 (cDe or Dce) is today most common in Africa. The allele was thus often assumed in early blood group analyses to have been typical of populations on the continent; particularly in areas below the Sahara. Given the presence of high R0 percentages among Sephardim and Ashkenazim Jews compared to native European populations and the relative genetic isolation of Ashkenazim, Ottensooser et al. (1963) therefore suggested that high R0 frequencies were likely characteristic of the ancient Judea Jews, who had emigrated from Egypt prior to their dispersal throughout the Mediterranean Basin and Europe.[15] However, more recent studies have found R0 frequencies as low as 24.3% among some Afroasiatic-speaking groups in the Horn of Africa,[16] as well as higher R0 frequencies among certain other Afroasiatic speakers in North Africa (37.3%)[17] and among some Palestinians in the Levant (30.4%).[18]

text:
Rh phenotypes and genotypes

Phenotype expressed on cell

Genotype expressed in DNA

Prevalence(%) †

Fisher-Race notation
Wiener notation

D+ C+ E+ c+ e+ (RhD+)
Dce/DCE
R0RZ

0.0125

Dce/dCE
R0rY

0.0003

DCe/DcE
R1R2

11.8648

DCe/dcE
R1r″

0.9992

DcE/dCe
R2r′

0.2775

DCE/dce
RZr

0.1893

D+ C+ E+ c+ e− (RhD+)
DcE/DCE
R2RZ

0.0687

DcE/dCE
R2rY

0.0014

DCE/dcE
RZr″

0.0058

D+ C+ E+ c− e+ (RhD+)
DCe/dCE
R1rY

0.0042

DCE/dCe
RZr′

0.0048

DCe/DCE
R1RZ

0.2048

D+ C+ E+ c− e− (RhD+)
DCE/DCE
RZRZ

0.0006

DCE/dCE
RZrY

< 0.0001

D+ C+ E− c+ e+ (RhD+)
Dce/dCe
R0r′

0.0505

DCe/dce
R1r

32.6808

DCe/Dce
R1R0

2.1586

D+ C+ E− c− e+ (RhD+)
DCe/DCe
R1R1

17.6803

DCe/dCe
R1r′

0.8270

D+ C− E+ c+ e+ (RhD+)
DcE/Dce
R2R0

0.7243

Dce/dcE
R0r″

0.0610

DcE/dce
R2r

10.9657

D+ C− E+ c+ e− (RhD+)
DcE/DcE
R2R2

1.9906

DcE/dcE
R2r″

0.3353

D+ C− E− c+ e+ (RhD+)
Dce/Dce
R0R0

0.0659

Dce/dce
R0r

1.9950

D− C+ E+ c+ e+ (RhD−)
dce/dCE
rrY

0.0039

dCe/dcE
r′r″

0.0234

D− C+ E+ c+ e− (RhD−)
dcE/dCE
r″rY

0.0001

D− C+ E+ c− e+ (RhD−)
dCe/dCE
r′rY

0.0001

D− C+ E+ c− e− (RhD−)
dCE/dCE
rYrY

< 0.0001

D− C+ E− c+ e+ (RhD−)
dce/dCe
rr′

0.7644

D− C+ E− c− e+ (RhD−)
dCe/dCe
r′r′

0.0097

D− C− E+ c+ e+ (RhD−)
dce/dcE
rr″

0.9235

D− C− E+ c+ e− (RhD−)
dcE/dcE
r″r″

0.0141

D− C− E− c+ e+ (RhD−)
dce/dce
rr

15.1020

text: † Figures taken from a study performed in 1948 on a sample of 2000 people in the United Kingdom.[19]

text:
Rh phenotypes in patients and donors in Turkey[20]

Rh Phenotype
CDE
Patients (%)
Donors (%)

R1r
CcDe
37.4
33.0

R1R2
CcDEe
35.7
30.5

R1R1
CDe
5.7
21.8

rr
ce
10.3
11.6

R2r
cDEe
6.6
10.4

R0R0
cDe
2.8
2.7

R2R2
cDE
2.8
2.4

rr″
cEe
–
0.98

RZRZ
CDE
–
0.03

rr′
Cce
0.8
–

text: Hemolytic disease of the newborn[edit]

text: The hemolytic condition occurs when there is an incompatibility between the blood types of the mother and the fetus. There is also potential incompatibility if the mother is Rh negative and the father is positive. When any incompatibility is detected, the mother often receives an injection at 28 weeks gestation and at birth to avoid the development of antibodies toward the fetus. These terms do not indicate which specific antigen-antibody incompatibility is implicated. The disorder in the fetus due to Rh D incompatibility is known as erythroblastosis fetalis.

text:
Hemolytic comes from two words: "hema" (blood) and "lysis" (solution) or breaking down of red blood cells
Erythroblastosis refers to the making of immature red blood cells
Fetalis refers to the fetus.

tag: ul

text: When the condition is caused by the Rh D antigen-antibody incompatibility, it is called Rh D Hemolytic disease of the newborn or Rh disease. Here, sensitization to Rh D antigens (usually by feto-maternal transfusion during pregnancy) may lead to the production of maternal IgG anti-D antibodies which can pass through the placenta. This is of particular importance to D negative females at or below childbearing age, because any subsequent pregnancy may be affected by the Rh D hemolytic disease of the newborn if the baby is D positive. The vast majority of Rh disease is preventable in modern antenatal care by injections of IgG anti-D antibodies (Rho(D) Immune Globulin). The incidence of Rh disease is mathematically related to the frequency of D negative individuals in a population, so Rh disease is rare in old-stock populations of Africa and the eastern half of Asia, and the Indigenous peoples of Oceania and the Americas, but more common in other genetic groups, most especially Western Europeans, but also other West Eurasians, and to a lesser degree, native Siberians, as well as those of mixed-race with a significant or dominant descent from those (e.g. the vast majority of Latin Americans and Central Asians).

text:
Symptoms and signs in the fetus:
Enlarged liver, spleen, or heart and fluid buildup in the fetus' abdomen seen via ultrasound.
Symptoms and signs in the newborn:
Anemia that creates the newborn’s pallor (pale appearance).
Jaundice or yellow discoloration of the newborn’s skin, sclera or mucous membrane. This may be evident right after birth or after 24–48 hours after birth. This is caused by bilirubin (one of the end products of red blood cell destruction).
Enlargement of the newborn’s liver and spleen.
The newborn may have severe edema of the entire body.
Dyspnea or difficulty breathing.

text: Population data[edit]

text: The frequency of Rh factor blood types and the RhD neg allele gene differs in various populations.

text:
Population data for the Rh D factor and RhD neg allele[21]

Population

Rh(D) Neg

Rh(D) Pos

Rh(D) Neg alleles

African Americans

∼ 7%

93%

∼ 26%

Basques[22]

21%-36%

65%

∼ 60%

Britain[23]

17%

83%

China[23]

<1%

>99%

Ethiopians[23]

1%-21%

99%-79%

Europeans (others)

16%

84%

40%

India[23]

0.6%-8.4%

99.4%-91.6%

Indonesia[23]

<1%

>99%

Japan[23]

<1%

>99%

Koreans[24]

<1%

>99%

Madagascar[23]

1%

99%

Moroccans[25]

9.5%

90.5%

Moroccans (High Atlas)[26]

∼ 29%

71%

Native Americans

∼ 1%

99%

∼ 10%

Nigeria[27]

6%

94%

Saudi Arabia[28]

8.8%

91.2%

29.5%

Subequatorial Africa[23]

1%-3%

99%-97%

United States[23]

15%

85%

text: Inheritance[edit]

text: If both of a child’s parents are Rh negative, the child will definitely be Rh negative. Otherwise the child may be Rh positive or Rh negative, depending on the parents' specific genotypes.[29]

text: The D antigen is inherited as one gene (RHD) (on the short arm of the first chromosome, p36.13–p34.3) with various alleles. Though very much simplified, one can think of alleles that are positive or negative for the D antigen. The gene codes for the RhD protein on the red cell membrane. D− individuals who lack a functional RHD gene do not produce the D antigen, and may be immunized by D+ blood.

text: The epitopes for the next 4 most common Rh antigens, C, c, E and e are expressed on the highly similar RhCE protein that is genetically encoded in the RHCE gene, also found on chromosome 1. It has been shown that the RHD gene arose by duplication of the RHCE gene during primate evolution.[citation needed] Mice have just one RH gene.[30]

text: The RHAG gene, which is responsible for encoding Rh-associated glycoprotein (RhAG), is found on chromosome 6a.

text: The polypeptides produced from the RHD and RHCE genes form a complex on the red blood cell membrane with the Rh-associated glycoprotein.[31]

text: Function[edit]

text: On the basis of structural homology it has been proposed that the product of RHD gene, the RhD protein, is a membrane transport protein of uncertain specificity (CO2 or NH3) and unknown physiological role.[32][33] The three-dimensional structure of the related RHCG protein and biochemical analysis of the RhD protein complex indicates that the RhD protein is one of three subunits of an ammonia transporter.[34][35] Three recent studies[36][37][38] have reported a protective effect of the RhD-positive phenotype, especially RhD heterozygosity, against the negative effect of latent toxoplasmosis on psychomotor performance in infected subjects. RhD-negative compared to RhD-positive subjects without anamnestic titres of anti-Toxoplasma antibodies have shorter reaction times in tests of simple reaction times. And conversely, RhD-negative subjects with anamnestic titres (i.e. with latent toxoplasmosis) exhibited much longer reaction times than their RhD-positive counterparts. The published data suggested that only the protection of RhD-positive heterozygotes was long term in nature; the protection of RhD-positive homozygotes decreased with duration of the infection while the performance of RhD-negative homozygotes decreased immediately after the infection. The overall change in reaction times was always larger in the RhD-negative group than in the RhD-positive.

text: Origin of RHD polymorphism[edit]

text: This section  possibly contains original research. Please improve it by verifying the claims made and adding inline citations. Statements consisting only of original research should be removed. (December 2009) (Learn how and when to remove this template message)

text: For a long time, the origin of RHD polymorphism was an evolutionary enigma.[39][40][41] Before the advent of modern medicine, the carriers of the rarer allele (e.g. RhD-negative women in a population of RhD positives or RhD-positive men in a population of RhD negatives) were at a disadvantage as some of their children (RhD-positive children born to preimmunised RhD-negative mothers) were at a higher risk of fetal or newborn death or health impairment from hemolytic disease. It was suggested that higher tolerance of RhD-positive heterozygotes against Toxoplasma-induced impairment of reaction time [36][37] and Toxoplasma-induced increase of risk of traffic accident[38] could counterbalance the disadvantage of the rarer allele and could be responsible both for the initial spread of the RhD allele among the RhD-negative population and for a stable RhD polymorphism in most human populations. It was also suggested that differences in the prevalence of Toxoplasma infection between geographical regions (0–95%) could also explain the striking variation in the frequency of RhD-negative alleles between populations. According to some parasitologists,[36] it is possible that the better psychomotor performance of RhD-negative subjects in the Toxoplasma-free population could be the reason for spreading of the “d allele” (deletion) in the European population. In contrast to the situation in Africa and certain (but not all) regions of Asia, the abundance of wild cats (definitive hosts of Toxoplasma gondii) in Europe was very low before the advent of the domestic cat.

text: Weak D[edit]

text: In serologic testing, D positive blood is easily identified. Units which are D negative are often retested to rule out a weaker reaction. This was previously referred to as Du, which has been replaced.[42]:322 By definition, weak D phenotype is characterized by negative reaction with anti-D reagent at immediate spin (IS), negative reaction after 37 °C incubation, and positive reaction at anti-human globulin (AHG) phase. Weak D phenotype can occur in several ways. In some cases, this phenotype occurs because of an altered surface protein that is more common in people of European descent. An inheritable form also occurs, as a result of a weakened form of the R0 gene. Weak D may also occur as "C in trans", whereby a C gene is present on the opposite chromosome to a D gene (as in the combination R0r', or "Dce/dCe"). The testing is difficult, since using different anti-D reagents, especially the older polyclonal reagents, may give different results.

text: The practical implication of this is that people with this sub-phenotype will have a product labeled as "D positive" when donating blood. When receiving blood, they are sometimes typed as a "D negative", though this is the subject of some debate. Most "Weak D" patients can receive "D positive" blood without complications.[42]:323 However, it is important to correctly identify the ones that have to be considered D+ or D−. This is important, since most blood banks have a limited supply of "D negative" blood and the correct transfusion is clinically relevant. In this respect, genotyping of blood groups has much simplified this detection of the various variants in the Rh blood group system.

text: Partial D[edit]

text: It is important to differentiate weak D (due to a quantitative difference in the D antigen) from partial D (due to a qualitative difference in the D antigen). Simply put, the weak D phenotype is due to a reduced number of D antigens on a red blood cell. In contrast, the partial D phenotype is due to an alteration in D-epitopes. Thus, in partial D, the number of D antigens is not reduced but the protein structure is altered. These individuals, if alloimmunized to D, can produce an anti-D antibody. Therefore, partial D patients who are donating blood should be labeled as D-positive but, if receiving blood, they should be labeled as D-negative and receive D-negative units.[31]

text: In the past, partial D was called 'D mosaic' or 'D variant.' Different partial D phenotypes are defined by different D epitopes on the outer surface of the red blood cell membrane. More than 30 different partial D phenotypes have been described.[31]

text: Rhnull phenotype[edit]

text: Rhnull individuals have no Rh antigens (no Rh or RhAG) on their red blood cells.[43] This condition is rare.[43] As a consequence of Rh antigen absence, Rhnull red blood cells also lack LW and Fy5 and show weak expression of S, s, and U antigens. Red blood cells lacking Rh/RhAG proteins have structural abnormalities (such as stomatocytosis) and cell membrane defects that can result in hemolytic anemia.[31][43]

text: Other Rh group antigens[edit]

text: Currently, 50 antigens have been described in the Rh group system; among those described here, the D, C, c, E and e antigens are the most important. The others are much less frequently encountered or are rarely clinically significant. Each is given a number, though the highest assigned number (CEST or RH57 according to the ISBT terminology) is not an accurate reflection of the antigens encountered since many (e.g. Rh38) have been combined, reassigned to other groups, or otherwise removed.[42]:324

text: Rh antibodies[edit]

text: Rh antibodies are IgG antibodies which are acquired through exposure to Rh-positive blood (generally either through pregnancy or transfusion of blood products). The D antigen is the most immunogenic of all the non-ABO antigens.  Approximately 80% of individuals who are D-negative and exposed to a single D-positive unit will produce an anti-D antibody. The percentage of alloimmunization is significantly reduced in patients who are actively exsanguinating.[44]

text: All Rh antibodies except D display dosage (antibody reacts more strongly with red cells homozygous for an antigen than cells heterozygous for the antigen (EE stronger reaction vs Ee).

text: If anti-E is detected, the presence of anti-c should be strongly suspected (due to combined genetic inheritance). It is therefore common to select c-negative and E-negative blood for transfusion patients who have an anti-E. Anti-c is a common cause of delayed hemolytic transfusion reactions.[31]