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71,551,291 | https://en.wikipedia.org/wiki/Marie-Louise%20Saboungi | Marie-Louise Saboungi is a Lebanese-born American condensed matter physicist at the Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), Sorbonne University, Paris, France.
Early life and education
Saboungi was born January 1, 1948, in Lebanon. She studied Mathematics and Physics at the Lebanese University in Beirut and obtained a Doctorat d’Etat in Physics at Aix-Marseille University, France in 1973, studying the statistical thermodynamics of molten salts.
Career
After her doctorate, Saboungi joined Argonne National Laboratory and worked there as Senior Scientist until 2002. Following this she was a director at the Centre de Recherche sur la Matière Divisée, CNRS until 2011. From 2007 to 2011 she was also Program Officer at Agence Nationale de la Recherche.
In 2011 she joined IMPMC at Sorbonne University, where she currently works.
She has also been a Distinguished Professor of Physics at University of Orléans in 2002–2011, and was appointed Distinguished Visiting Professor in Soochow University in 2014.
Research
Saboungi's work focuses on complex soft materials, including ionic liquids and aqueous electrolytes, with a view to applications in energy and biotechnology. She also studies silver chalcogenides, which display many fascinating phenomena including fast-ion conduction at higher temperatures, linear magnetoresistance over a broad range of magnetic fields, and topological insulator behavior.
Awards and honours
1990 – Fellow of the American Association for the Advancement of Science
1991 – Award for Leadership in the Professions, YWCA of Metropolitan Chicago
1992 – Fellow of the American Physical Society
2000, 2014 – Fellow of Japan Society for the Promotion of Science
2007 – Fellow, Alexander von Humboldt Foundation
2014 – Doctor Honoris Causa, University of the Andes, Mérida, Venezuela
Selected publications
Large magnetoresistance in non-magnetic silver chalcogenides, Nature 390, 57–60 (1997),
Electron distribution in water, J. Chem. Phys. 112, 9206 (2000),
Improving reinforcement of natural rubber by networking of activated carbon nanotubes, Carbon, 46, 7, June 2008, 1037–1045,
The Structure of Aqueous Guanidinium Chloride Solutions, J. Am. Chem. Soc. 2004, 126, 37, 11462–11470,
References
External links
List of patents
Living people
Condensed matter physicists
Women physicists
Fellows of the American Physical Society
Fellows of the American Association for the Advancement of Science
Aix-Marseille University alumni
Pierre and Marie Curie University people
1948 births | Marie-Louise Saboungi | [
"Physics",
"Materials_science"
] | 541 | [
"Condensed matter physicists",
"Condensed matter physics"
] |
71,552,759 | https://en.wikipedia.org/wiki/Aegis%20Sonix | Aegis Sonix is a music sequencer, software synthesizer and a score editor for the Amiga created by Aegis Development and published in 1987. The application offers a combination of a notation editor and an editor of digital sounds and is able to edit IFF music instruments and other digital sound files.
History
Commodore International developed but never officially released a sound application called Musicraft for its Amiga series of computers. Aegis Development bought rights to Musicraft from Commodore and contracted the original developers Mark Riley and Gary Koffler to continue its development. The application - now under the Aegis Sonix name - was released in 1987. in 1989, Aegis left the Amiga market and sold its software products to a Californian software producer Oxxi, Inc, which continued to use the Aegis brand.
Features
The software includes a score, keyboard, and an instrument editor. The program uses two file formats, the SMUS file format, which is an IFF based tracker module music format, and the INSTR file format which contains the instrument data. Sonix can also read music files created by Deluxe Music Construction Set and works as a MIDI sequencer. Sonix offers 8 music tracks: the first four are useable for 4 voices of the Amiga sound hardware and also for the MIDI instruments, the other four are available only for the MIDI instruments. All 8 tracks are independent of each other and can be used at the same time. The score editor allows to write notation for sheet music. The application serves primarily a music synthesis tool for creation of analog or digital sounds and is able to edit IFF music instruments and other digital sound files.
Reception
A review in the French magazine Tilt commended easy to use menus and good documentation and highlighted the combination of a notation editor and an editor of digital sounds as the main strong point of the application. The AmigaNews magazine evaluated the use of Sonix with MIDI and noted among several benefits few limitations: the program doesn't support recording of a key press on the MIDI keyboard. Sonix was also reviewed in the Keyboard magazine.
See also
Deluxe Music Construction Set
References
1987 software
Amiga software
Scorewriters
Music sequencers | Aegis Sonix | [
"Engineering"
] | 434 | [
"Music sequencers",
"Automation"
] |
71,553,058 | https://en.wikipedia.org/wiki/Panorama%20of%20the%20City%20of%20New%20York | The Panorama of the City of New York is an urban model of New York City that is a centerpiece of the Queens Museum. It was originally created for the 1964 New York World's Fair.
Early history
In June 1961, the New York City Board of Estimate awarded a contract to the architectural model makers Raymond Lester Associates for the construction of a scale model of New York City within the City Building. City officials planned to install suspended cars to allow visitors to see the model during the 1964 New York World's Fair. The Panorama was built by a team of 100 people working for Lester Associates in West Nyack, New York in the three years before the opening of the 1964 World's Fair.
Commissioned by World's Fair Corporation president Robert Moses as a celebration of the City's municipal infrastructure, this model includes every single building constructed before 1992 in all five boroughs, at a scale of 1 inch = 100 feet (1:1200). The model was constructed in 273 sections of Formica boards and polyurethane foam, originally depicting 835,000 individual structures. The section showing the Far Rockaway neighborhood was never installed, due to space limitations. The original Panorama included about 25,000 Plexiglass models of major buildings, 100,000 handmade models of less substantial structures, and 50,000 models of churches. For other structures such as tenements and brownstones, Lester Associates created 50,000 copies of each type of structure. In total, Lester Associates manufactured about two to three million buildings, including duplicates.
Displayed alongside the modern city, the 1964 exhibition also included a 1:300 diorama of a "Castello Model" based on the 17th century Castello Plan, borrowed from Museum of the City of New York.
The Panorama was one of the most successful attractions at the 1964 Fair, with "millions" of people paying 10 cents each for a 9-minute simulated helicopter ride around the City, a dark ride narrated by Lowell Thomas to a text written by Harvey Yale Gross. It was one of three colossal representations of geography at the fair, alongside the Unisphere and the New York State Pavilion. Visitors could also look at the model from a balcony and, for another 10 cents, could peer at specific neighborhoods using binoculars.
The panorama was also intended to serve as a standing urban planning tool after the fair, after Moses' vision. In this way it anticipated the technology of a 3D city model, though in practice it was of limited utility. It did however, play a role in the defeat of Donald Trump's 1980s Television City proposal, as a model put on the panorama by activists demonstrated the relative size of the development. Additionally, the opening of the Panorama was set to coincide with the 300-year anniversary of the English takeover of New Amsterdam—which occurred in 1664—and highlight the city's growth over that period.
After the Fair closed, the Panorama remained open to the public, and Lester's team updated the map in 1967, 1968, and 1969.
Later history
After another update in 1974, very few changes were made until 1992, when again Lester Associates was hired to update the model to coincide with the re-opening of the museum, after a two-year total renovation of the building by Rafael Viñoly. The model makers changed over 60,000 structures to bring it up-to-date at that time. There are now 895,000 structures total, including buildings made of plastic or wood. There are also bridges made of brass. The mechanical "helicopter" vehicles for conveying exhibition visitors were showing signs of wear, and were removed before the 1994 reopening. The current installation by Viñoly features accessible ramps and an elevated walkway which surround the Panorama, allowing viewers to proceed at their own pace, or to linger for as long a look as they desire. Because of space constraints, portions of the walkway are cantilevered over the outer edges of the map, but a glass floor still allows views of the model below. As in the original installation, tiny scale model airplanes take off and land at the model airport of LaGuardia Airport, mechanically guided by long wires.
In March 2009, the museum announced the intention to update the Panorama on an ongoing basis. To raise funds and draw public attention, the museum will allow individuals and developers to have accurate scale models made of buildings newer than the 1992 update created and added, in exchange for a donation of at least $50. More-detailed models of smaller apartment buildings and private homes, now represented by generic models, can also be added.
, the original Twin Towers of the World Trade Center are still on the map, even though some new buildings have been built on the actual site; the museum has chosen to allow the destroyed structures to remain until construction is complete, rather than representing the ongoing construction. The first new building to be added under the new program was the new Citi Field stadium of the New York Mets; the model of the old Shea Stadium was to be displayed elsewhere in the museum.
The New York City Panorama was featured in two 2011 fictional works: the movie New Year's Eve directed by Garry Marshall, and the book Wonderstruck by Brian Selznick, and also in a subsequent Wonderstruck film. A revamped lighting system was installed in 2017, as part of a sponsorship promoting the film. Photographer Spencer Lowell took images of the model in the art series New York, New York, New York in 2016, and these were acquired by the museum and versions were sold at art fairs. The model was also featured in the 2021 documentary series Pretend It's a City. Every year, the Queens Museum hosts the "Panorama Challenge", a trivia contest run by The City Reliquary; the inaugural contest was held in 2007. Contestants use the Panorama to identify various New York City landmarks.
In recent years, the panorama has often functioned as installation art, providing context for temporary site-specific works taking the form of model buildings, or otherwise displayed in the panorama's gallery.
A scale model of the 1964 New York World's Fair site, showing all the buildings and pavilions of the time, is located in a separate area devoted to World's Fair exhibits. It is built to the same scale as the Panorama by Lester and Associates, and was one of originally 7 travelling models. A larger model of the Fair site that was 1 inch : 32 feet was the one exhibited there in 1964.
See also
Shanghai Urban Planning Exhibition Center
Museum of Roman Civilization
References
1964 New York World's Fair
Closed amusement attractions
Dark rides
Installation art works
Maps of New York City
Robert Moses projects
Scale modeling
Trivia competitions | Panorama of the City of New York | [
"Physics"
] | 1,349 | [
"Scale modeling"
] |
71,553,727 | https://en.wikipedia.org/wiki/Princess%20Aubergine | Princess Aubergine (Baingan Bádsháhzádí) is an Indian folktale collected by Flora Annie Steel and sourced from the Punjab region. It concerns a princess whose lifeforce is tied to a necklace, and, as soon as it falls in the hand of a rival, the princess falls into a death-like sleep - comparable to heroines of European fairy tales Snow White and Sleeping Beauty. Variants exist in India, both with a heroine and a hero whose life is attached to a magical necklace.
Source
Richard Carnac Temple sourced the tale from an old woman of Purbia origin, at Kasur near Lahore.
Summary
A poor Brahman and his wife live in such a state of poverty, they resort to gathering roots and herbs to eat. One day, the Brahman finds an eggplant and brings it home to plant. He and his wife water it and it yields a large, purple fruit. The Brahman's wife takes a knife to cut open the large eggplant in the garden. When she stabs the large fruit, a low moan is heard. The wife stabs it again and a voice inside it the eggplant begs for the woman to be careful. The wife opens the eggplant and finds a little maiden inside, dressed in white and purple garments. The Brahman and his wife decide to adopt the girl as their daughter and name her Princess Aubergine.
Next to the Brahman's hut, a king lives with his queen and seven sons. One day, a slave-girl from the palace goes to the Brahman's hut to ask for some light, and sees Princess Aubergine. So lovely is she, that the slave-girl rushes back to the palace to tell the queen about her. The queen, despite being beautiful herself, is told that the Brahman's daughter is even more beautiful than her, and fears the king will replace her.
So the queen devises a plan: she invites Princess Aubergine to the palace, and convinces the girl to live there with her as the queen's sister. Time passes, and the Queen, adept in the arts of magic, learns through her powers that the Princess Aubergine is a fairy, and, while the maiden is asleep, casts spells on her to reveal the location of her lifeforce. The Princess murmurs that her lifeforce is in the queen's first son; by killing him, the queen will kill Aubergine.
The queen kills her firstborn son, and sends the servant-girl to check on Princess Aubergine, who is still alive. Failing her first attempt to kill the maiden, the queen goes back to enchanting the girl for her to disclose her secret. The princess keeps telling that her lifeforce lies in each of the queen's other sons, which are killed every time.
After all her sons have been killed, the queen, fueled with rage, manages to enchant Aubergine with even more powerful spells for her to reveal the location of her lifeforce: in a nine-lakh necklace, inside a tiny box, inside a bumblebee, inside a red and green fish that lives in a river somewhere far away.
The queen convinces her husband, the king, to procure her the nine-lakh necklace, like some sort of comfort due to the sudden loss of their sons, who, according to the queen, have died of a "mysterious illness". The king brings back the fish and the queen finds the fabled necklace. Meanwhile, Princess Aubergine, sensing her approaching death, goes back to her adoptive parents' hut and tells the Brahman to prepare her resting place: they must not bury her, but set her on her bed, deep in the wilderness, surround it with flowers, and build a mudwall around it.
The Brahman and his wife follow her instructions, and the queen's slave-girl reports back that Aubergine is not buried, by lies out in the open. The queen contents herself with this small victory, since she still has the necklace.
One day, the king decides to go on a hunt to occupy his mind off the loss of his seven sons, but the queen warns him against hunting in the north. The king hunts in the east, in the west, and in the south, and, out of options, begins to hunt in the north. The king sees the mudwall and the bed of flowers that surround Princess Aubergine's body. The king becomes entranced by her beauty and begins a long, secret vigil on her body. After a year, a son appears next to the maiden's body, and, some time later, the boy tells the king his mother, the maiden, comes alive at night to care for him, and dies in the morning.
The king then asks the boy about his origins, and the boy answers that he is the king's son and Aubergine's, sent to console him after the death of the king's seven sons by the hands of the queen. The boy also reveals that Aubergine can be revived by retrieving the nine-lakh necklace around the queen's neck, but he is the only one that can get it.
The king brings the boy with him to the palace. The queen, seeing the boy, tries to give him poisoned food, but the boy refuses to touch the food until the queen gives him the necklace to play. The queen, wanting to see the boy eat the food, gives him the necklace, and he hurries back to his mother Aubergine to revive her.
Upon placing the necklace on his mother, Princess Aubergine awakens. The king goes to her and talks her into coming to the palace with him and becoming his bride, but Aubergine refuses, until the king digs up a ditch, fills it with snakes and scorpions, and throws the queen inside it. The king orders some servants to fulfill her orders, then tells the king to come see something with him. Despite refusing, the queen is seized by the guards, tied up, thrown in the ditch and buried alive. Princess Aubergine and her son come to live in the palace with the king.
Analysis
Tale type
The tale is classified in the international Aarne-Thompson-Uther Index as tale type ATU 412, "The Maiden (Youth) with a Separable Soul in a Necklace". Folklorist Stith Thompson included in the same tale type stories about a heroine and a hero whose soul lies in a magical necklace.
According to German folklorist Hans-Jörg Uther, in the 2004 revision of the international index, tale type ATU 412 can appear in combination with another tale type: ATU 404, "The Blinded Bride". In this type, the heroine is blessed at birth by good spirits with the ability to produce gold with her tears and her hands, but, later in life, is blinded by a jealous rival, until a helper buys back her eyes.
Motifs
The tale contains the motif E711.4, "Soul in necklace".
Richard C. Temple stated that the original name of the tale, also known as baingan, bingan, begun and bhâņṭâ, refers to the plant Solanum melongena, that is, the eggplant or the aubergine.
Variants
India
Richard C. Temple noted that the tale "abound[ed] in various forms in the Pânjâb". In the second revision of the index, published in 1961, Stith Thompson located 7 variants in India.
In an Indian tale titled Princess Brinjal, a poor gardener asks a Koiri for alms, and is given a brinjal. The gardener's goes home, places the brinjal in a pot and cooks it. A rattle inside the pot draws the gardener's attention and he opens the pot to see a fairy (peri) and a "heavenly mansion" inside it. The princess introduces herself as "Princess Brinjal" and turns the gardener's poor hut in a grand palace, and they live together. Some time later, a Anir's wife goes to the Princess Brinjal and gives her some milk and curds, and is paid with a pearl. She goes to the Rája's palace to sell milk and curds, and is given wheat husks. She comments to a gatekeeper about Princess Brinjal's generosity, and the gatekeeper tells the Ráni about it. The Ráni fears her husband might want Brinjal as his new wife and decides to poison her. She goes to Brinjal's palace, who invites her in, despite knowing her plan. The Ráni, in turn, invites Brinjal to her palace, but she asks for the Ráni to pave a road between their palaces and decorate it with curtains, so that no man can see her. Princess Brinjal goes to the Ráni's palace. The Ráni tries to poison the princess with the food, but the princess declines to eat any dish. However, goaded by the Ráni, the princess tells her about a ruby necklace inside a box, located on the branches of a pipal tree. After the princess leaves, the Ráni asks her husband to get the necklace. He does and Princess Brinjal falls dead. Before she dies, she asks the gardener to build a tomb and lay her there. Time passes, and the Rája visits Brinjal's resting place. He drinks some water and eats half of a pomegranate. The same night, Brinjal awakens and eats the other half. She and the Rája fall in love and have a son. Brinjal tells the Ráj about the necklace; he takes it back from the Ráni and executes her, making Brinjal his new queen. The tale was sourced to a person named Ali Sajjad, a village accountant from Mirzapur, and collected by Pandit Ram Gharib Chaube, and also noted to be an "imperfect version" of Princess Aubergine.
Author M. N. Venkataswami collected an Indian tale titled The Fakeer's Daughter and the Wicked Queen. In this tale, a poor fakeer is visited by an even poorer fakeer in search of alms. The first fakeer's daughter becomes irritated with the second fakeer's insistence and drops a ladle of hot keer on the second fakeer's head, creating a blister on his hand. The second fakeer is instructed by the "angels from heaven" to let the blister be and, nine months later, a baby girl sprouts from the blister and asks for nourishing. The girl grows up and becomes a beautiful maiden. The rani of the place learns of the maiden's beauty, far surpassing her own, and decides to get rid of her, so she sends some servants to meet the maiden. The servants notice the "carcanet" (a collar) of jewels around her neck and, after a denied polite request, they take the jewels by force and bring them to the Rani. After the carcanet is hung up in the queen's room, the maiden dies. Her father, the second fakeer, is warned in a dream to place the body out in the open, under a sandalwood tree. Next to the body, flowers sprout and their fragrance draws the Raja to the maiden's resting place. He goes to pluck a beeda and eat, but four invisible paris ask him to bring back the jewels from the queen's room. The Raja takes the carcanet and places it on the sleeping maiden, who comes back to life, gives the beeda to the Raja and marries him, while the Rani is executed.
Author Mary Frere collected a Southern India tale titled Sodewa Bai. In this tale, a Ranee and a Rajah have a beautiful daughter named Sodewa Bai ('Lady Good Fortune'), and they summon the wise men to divine her future. The wise men interpret she will be very rich - since flowers and pearls fall from her lips whenever she speaks -, but caution the royal couple that they protect the necklace on the girl's neck, since she was born with it and removing it would mean her death. Years later, when the girl is fourteen years old, she has not found any suitor. Her parents also give her a pair of tiny slippers of gold and jewels. One day, she goes with some haidmaidens to fetch wildflowers in the slopes surrounding her palace, and lets one of her slippers slip away down the mountain. After learning of the loss, her parents announce a great reward for anyone that can return the missing pair. Meanwhile, the slipper in found in a jungle by the son of another Rajah, and the prince and his father marvel at the slipper, and decide the boy shall look for its owner to marry her. News of the proclamation of Sodewa Bai's parents reach his kingdom (since the prince lives in the Kingdom of the Plains) and he goes to the Mountain Kingdom of Sodewa Bai to deliver the missing slipper, and ask her to marry him. Sodewa Bai's parents tell the prince they will allow their marriage only if their daughter agrees, which she does, and they marry in a grand ceremony. After a while, the prince wants to take Sodewa Bai to his home kingdom, and his parents-in-law warn him to never let his wife take off her necklace. The prince agrees and goes back home, and the tale explains he was already married to a previous co-wife, who begins to dislike the presence of Sodewa Bai, whom she considers a rival. Sometime later, the prince, named Rowjee Rajah, has to leave to some distant part of his kingdom, and leaves Sodewa Bai under the care of his previous co-wife. After he leaves, the first wife notices the golden necklace on Sodewa Bai's neck, and inquires about it. The girl naïvely reveals the secret of the necklace, and the first co-wife orders a "negress" to steal the object at night. The servant does and places it on her own neck; Sodewa Bai does not wake up the next day and her parents-in-law believe her to be dead, so they move their body to an open tomb near a water tank. After Rowjee Rajah returns, he learns of his second wife's apparent death and mourns for her. Meanwhile, at her tomb, Sodewa Bai awakes everytime the servant removes the necklace at night, and falls into her death-like sleep in the morning. As time passes, she gives birth to a son, and she leaves pearls to float in the water tank. Rowjee Rajah notices the pearls in the water and decides to investigate on the first days, but returns after the baby is born, and hears someone inside the tomb. The prince realizes Sodewa Bai is alive and is told about the necklace, which is not around her neck. The prince returns to the palace, retrieves his wife's necklace and restores her life. Sodewa Bai returns to the palace with her son, and the first co-wife and her servant are punished.
In an Orissan tale collected from a Bhatra source in Nabarangpur district with the title Tale of Florist's Daughter and Serpent, a serpent opens its crest near a baby girl, which the girl's paternal aunt witnesses. Thinking the girl must be of the snake species, the baby's father abandons the baby in the forest under a tree. An old florist finds the baby crying and brings her home, keeping her hidden from his neighbours. The florist's wife contributes with the deception by pretending to be pregnant, then feigns labour pains and presents the baby girl as her own child. An astrologer then comes to name the girl and suggests the name Tulasa. When the girl grows a bit older, she goes to play with the princess by the king's fence, and the king's co-wives, afraid the girl might draw the king's attention away from her, expel her from approaching the palace. Later, when Tulasa becomes a beautiful young lady, she goes to the palace to sell some flowers. The co-queens notice their rival is there again, and decide to kill the girl and burn the body. They send some messengers to kill Tulasa in the jungle, but she tricks her would-be executors by saying her lifeforce is in the trunk of the king's prized elephant, which they should kill first. Tulasa escapes from the messengers, and her friend, the princess, learns of the co-queens' plot to kill the florist girl. The co-queens move to a second attempt; they order the messengers to kill her, and Tulasa, now, reveals the secret: somewhere in the seven seas, there are seven rooms, one with an idol inside; on the idol there are seven golden chains of seven tolas, wherein lies her death; the soldiers must behead the idol's head and the seven necklaces will be detached from its neck, killing her. The messengers follow Tulasa's instructions and destroy the idol and the necklaces, ending the girl's life. Thus, in order to cover up their crime, the messengers cover the girl's body and take her to be cremated, when the king arrives and asks them the meaning of their action. The messengers say they are taking a dead girl's body with no kith nor kin to be cremated, but the shroud falls from the body and reveals Tulasa's beauty to the king. Stunned at her beauty, the monarch orders them to explain themselves, when a monkey climbs down a tree and revives Tulasa with a herb. The little animal then explains everything to the king and says the girl is meant for him. At the end of the tale, the king executes his co-wives and takes Tulasa as his queen.
Pakistan
In a Sindhi tale published by Sindhologist Nabi Bakhsh Baloch with the title The Ghaibi (Unseen) Queen (Sindhi: "غيبي راڻي"), a farmer grows watermelons in his orchard. One day, his wife goes to the orchard and hears a voice, then rushes to tell her husband about it. The couple return to the orchard and find a watermelon which they bring home. From the watermelon a baby girl appears, whom they raise as their daughter. When she grows up, news of her beauty draws many suitors, who are rejected. A king learns of her beauty and goes to the farmer's house to ask for her hand. Their marriage is arranged, and the king brings the watermelon girl to his palace. The king is previously married to two co-queens, who become increasingly jealous of the way the king dotes on the new girl, so they hire a dhooti (evil woman) to discover something about the new queen that the duo can use against her. The dhooti pays a visit to the third queen and they talk: unknowingly, the watermelon girl reveals her life (soul) is located inside a pearl in her necklace, which, if one is to remove from her, she would lose her life. Armed with this information, the dhooti steals the necklace and brings it to the other queens. The watermelon girl, who is pregnant, begins to feel dizzy and suffocated, and, sensing the upcoming danger, she tells the king to have her body safely installed in a room, instead of being buried, in case she dies. The jealous queens celebrate the "death" of their rival, and keep the necklace in a safe place. The watermelon girl eventually dies and, just as she requested, her body is placed in a room. Back to the queens, they alternate using the necklace by morning and hiding it at night, which causes the watermelon girl to revive at night and die by day. A baby son is born to the girl, who tells her child to explain the situation to his father, the king. Time passes, and the king decides to pass by the room where his third queen's body is kept, and finds a child playing by his wife's body. He decides to wait for the evening, and discovers the girl comes back to life to play with the baby. The king reunites with his wife and is told of the co-queens' plot, then they trace a course of action: he will steal back the necklace. The next day, the king sends a poor man near the palace to beg for alms, and asks for the necklace. The queens give the necklace to the beggar, who returns it to the king, who places it around the watermelon girl's neck. The king brings his wife and son back to the palace and expels the two queens.
Egypt
Folklore scholar Hasan M. El-Shamy registers a single variant of type ATU 412 in the Middle East and Northern Africa, which he located in Egypt.
Folklorist Howard Schwartz published a Jewish-Egyptian tale titled The Wonder Child: a rabbi and his wife pray to God to have a child. One night, at midnight, during Shevuoth, they pray to God. The rabbi's wife has a dream about a girl clutching a jewel in her hand, and a voice tells her that the child and the jewel can never be parted. Nine months later, she gives birth to a girl with a jewel, and names her Kohava ("star"). The rabbi also places the jewel inside a necklace. Kohava grows up to be a lovely and talented maiden. One day, the queen announces she will go to the bath house, and invites every woman. Kohava insists she wants to visit the bath house. Kohava goes to the bath house and draws everyone's attention due to her beauty. Even the queen notices she is more beautiful then herself, and fear her son, the prince, will wish to marry her. So the queen orders her servants to bring instruments for the girl to play, which she does with ease. Astonished by her talents, the queen convinces the girl's parents to take her to the palace as one of her musicians. Kohava's mother advises her daughter never to take the necklace off her. After they reach the palace, the queen orders Kohava to be sent to prison, so she can perish there, but a guard gives her food. A while later, the queen goes to check on Kohava, and sees she is still alive, but notices the glowing necklace. The queen takes the necklace by force and the girl falls asleep. The queen orders the guard to dispose of the body, but he simply places her inside a hut. Then, the queen's son, the prince, goes on a hunt and finds Kohava, lying asleep in the hut. He falls in love with her, but she cannot awake. At any rate, the prince goes back home and tells his mother he is in love with a princess, and the queen gives him Kohava's necklace as a betrothal gift for his bride. The prince goes back to the hut and places the necklace around Kohava's neck. She wakes up sees the prince; they each relate the story, and the prince learns of his mother's cruelty. The prince announces he will marry, and asks his mother to prepare a grand celebration. The bride is walked in wearing seven veils, and, when she lifts them, the queen sees Kohava is alive and flees. Kohava and the prince live happily ever after. In his notes, Schwartz noted it to be a cross between European tales Snow White and Sleeping Beauty.
Caucasus Region
Georgia
The Georgian Folktale Index registers a similar narrative of a heroine's magical necklace, indexed as type 412, "The Marble Tears and Necklace". In the Georgian tale type, the heroine is capable of producing flower petals with her laughter and tears of pearls when she cries, and also possesses a magical necklace she can never part with. During the tale, the heroine falls into a death-like sleep when her rival steals the necklace. The prince, the heroine's husband, discovers the necklace, but it is their son that brings it back to the heroine.
Armenia
In a tale collected by Susan Hoogasian-Villa from an Armenian-American source, The Fairy Child, a king overhears his youngest daughter talking that woman is more important that man. Angered at her commentary, he marries his two elder daughters to rich princes and the youngest to a poor man. Regardless of her poor situation, the third princess gives birth to a girl. One night, the baby girl is visited by four angels, who give her blessings. The first gives her a necklace she is to never part with, otherwise she will die; the other angels bestow marvellous gifts upon her: when she bathes, her bathwater turns to gold; when she cries, pearls fall from her eyes, and when she laughs, red roses will bloom on her cheeks. Later, when she grows up, the heroine, now a woman, alerts her helper, an old man, that her rival will steal her necklace, and the heroine will appear to be dead, but she is not to be buried.
Karachay-Balkar people
In a tale from the Karachay-Balkars with the title "Алакез" ("Alakez"), an old couple suffer for not having children, until one day a girl is born to them, one cheek shining like the moon and the other like the sun. One night, as they place the girl in the cradle and occupy themselves with other chores, white genies come to the baby to bestow upon her gifts: the first ties a magical talisman (хамайылчи́к, 'hamayylchik') to her right hand, which will protect her at all times, and blesses her with the ability to cry diamond tears; the second blesses her with the ability to have gold appear whenever she bathes, and the third that wherever she steps flowers will appear. The girl grows up in beauty and charm, and, when she is of marriageable age, a young khan from a nearby khanate learns of her beauty and wishes to marry her. Thus, her parents prepare to send their daughter Alakez to the khan, escorted by an old woman neighbour and her own daughter. As they travel through a forest, the neighbour blinds Alakez and takes out her eyes, then dresses her own daughter as Alakez to trick the khan, and abandon the other girl in the woods. As the tale continues, a kind old man named Ivan takes Alakez in and she buys her eyes back. She also asks her friend Ivan to build a giant tower as her tomb, in case she dies, and the doors must open every day by themselves and mourn for her. Ivan fulfills her request. As for the neighbour woman, she learns of Alakez's magical talisman and orders a spy to steal it. He does and Alakez falls to the ground as if dead. Ivan then places her inert body in the tower. One night, the khan is riding next to the tower accompanied by a servant, and both hear the tower windows mourning for a girl. They enter the tower and see Alakez's dead body, the mark of a talisman on the right side of her body. The khan notices the servant has with him something that might be the perfect match, and bids him place it on the body. Alakez wakes up and asks to be taken to her friend Ivan and his wife, where the whole truth is told to the khan.
Turkey
Scholars Wolfram Eberhard and Pertev Naili Boratav devised a classification system for Turkish folktales and narratives, called Typen türkischer Volksmärchen ("Turkish Folktale Catalogue"). In their joint work, they registered a Turkish tale type indexed as TTV 240, "Rosenlachen und Perlenweinen" ("Rose-Laughter and Pearl-Tears"), with 29 variants listed. In the tale type, the heroine is born to a poor couple, and dervishes, fairies or peris come to bless the child with the ability to produce rose petals with her laughter and pearls with her tears, and also give her an amulet. Later in the tale, the heroine's rival steals the heroine's amulet; the heroine falls into a death-like sleep, and her body is placed in a mausoleum.
Uzbekistan
In an Uzbek tale titled "Дочь дровосека" ("The Woodcutter's Daughter"), a poor and childless woodcutter earns his living by chopping firewood in the mountains and selling it. One day, he chops down a very old tree and releases a good djinn, who, in gratitude, explains an evil djinn imprisoned him there, and gives the man a magical apple for the man and his wife to eat. The good djinn explains a girl will be born to them, but one that produces pearls with her tears, flowers with her words, and golden sand wherever she steps on. It happens thus, and a girl is indeed born to them. As she grows up, her father demands a particularly steep dowry for her, which shuns many suitors. One day, however, the evil djinn appears and demands the man delivers him his daughter as wife, which he refuses to do. A young batyr comes and drives away the djinn, and the woodcutter, in return, agrees to marry his daughter to the batyr. Some time later, as the journey is long for them, and they are old, the woodcutter and his wife cannot make the journey, when suddenly a rich old woman comes with her daughter and offers to take the girl to her bridegroom, since the old woman is his aunt. The woodcutter agrees, but, during the journey, the old woman demands the girl's pearl-producing eyes and makes her blind. Later, the girl buys her eyes back. The old woman joins forces with the evil djinn, who tells her to fetch a certain golden fish in the river which contains a special earring that holds the girl's lifeforce within. The old woman does as instructed, takes the earring and wears it; the girl enters a death-like state and her body is placed on a tomb. However, the girl wakes up whenever the old woman removes the earring, and falls dead when the earring is worn. One day, the batyr, who is the girl's bridegroom, hunts a white dove and follows it to the tomb, where he finds his true bride. The girl wakes up and explains his aunt has the earring with her lifeforce inside.
Male heroes
Lal Behari Dey collected a similar tale from Bengal in his work Folk-Tales of Bengal, albeit with a male hero. In this tale, Life's Secret, a king has two wives, Suo and Duo, both childless. One day, a fakeer goes to the palace to beg for alms, and is greeted by queen Suo, who gives him a handful of rice. In return, the fakeer gives her a nostrum, to be swallowed with the juice of a pomegranate flower; the queen will give birth to a son she will name Dalim Kumar ("Dalim" - pomegranate; "Kumar" - son). The fakeer also warns her that her son's life will be bound to a necklace of gold, inside a wooden box, inside a boal fish's heart that lives in a pool in the palace. In time, Suo gives birth to Dalim Kumar. The boy grows up and likes to play with pigeons. One day, a pigeon flies in Duo queen's quarters. Duo promises to return the pigeon if Dalim asks his mother the secret of this life. Dalim Kumar talks to his mother about it; at first, Suo relates in telling her son about it, but eventually concedes and tells him about the necklace. Dalim Kumar tells his step-mother about it. Duo begins a plan: with some herbs, she feigns that her bones are so frail that they crackle and pop, and her only cure is the boal fish. After the fish is caught, at the same time Dalim begins to feel unwell and, as the wooden box is open and Duo places Dalim's necklace around her neck, Dalim falls dead. The king's grief is so deep, and he orders his son's body to be placed in one of his garden-houses, with provisions, and trusts the son of his prime minister, Dalim Kumar's friend, with the keys to his tomb. Dalim Kumar wakes up at night while his step-mother does not wear the necklace, and dies in the daytime so long as Duo wears the necklace. After some time, the prime minister's son notices that, despite being dead, Dalim Kumar's body does not decay, and decides to investigate further. Dalim Kumar's friends discovers he is alive, and both plot to retrieve the necklace. Meanwhile, BIdhata-Purusha's sister gives birth to a daughter, and Bidhata-Purusha prophesises his niece shall marry a dead bridegroom. After she comes of age, her mother takes the girl with her to avoid her fate, and they reach Dalim Kumar's garden-palace. The girl enters the palace and meets Dalim Kumar, who claims to be her future dead bridegroom. Dalim Kumar's friend marries them and leaves them be. The next day, Dalim Kumar "dies" again, to his wife's consternation, but revives at night. The girl learns of his condition and, after some years, and the birth of their two children, decides to meet her step-mother-in-law and retrieve her husband's necklace. The girl disguises herself as a poor female barber and goes to Queen Duo's palace to hire herself. Unaware of the girl's identity, she takes her in as her servant. The girl instructs her elder son to play with the necklace around Duo's neck, and to cry if the boy parts with it. Duo lets the child play with the necklace, certain of her triumph. Dalim Kumar's wife steals the necklace and brings it back to her husband. Dalim Kumar, his friend and his family enter the king's palace with grandeur; the prince meets his parents and tells the whole truth. The king then sentences his queen Duo to be buried alive.
In a tale collected by Tapanmohan Chatterji with the title Dalim-Koumar ou Le Prince Grenade, a king has two queens, Suo and Duo. Suo has a child, while Duo is childless, and envies the other. Suo's son is named Dalim-Koumar, since his life is tied to a pomegranate. One day, one of Dalim's doves flies to Duo's room and she catches it. Duo promises to return it, if the boy reveals where his "life" is. The boy retorts that his life is inside him, but the queen explains that an astrologer told the boy's mother the boy's life is inside the pomegranate, and Duo wants to know where it is. Dalim runs to his mother to ask her about it and, despite some avoidance, Suo tells him the secret. Dalim goes to tell Duo the information. Some time later, queen Duo feigns illness, and she tells the king her only cure is a certain pomegranate on a certain tree that lies away from the village. The king's servant takes the pomegranate from the tree, which instantly causes the boy to fall ill. Duo cracks open the fruit and finds a little box with a golden necklace inside. She wears it on her neck and Dalim falls dead immediately. The king and Suo cry for their lost son, and order his body to be placed inside a white marbled pavilion. Meanwhile, Dalim Kumar's fiancée, a princess, prepares herself for the sati, but promises to defeat death by the strength of her love and by giving offerings to the gods. The princess decides to vigil his body alone, in the pavilion. All the while, queen Suo retires to her chambers out of grief, and Duo becomes the king's favourite, being showered with affection and jewels, but, in order to avoid suspicions, takes off the necklace at night - which revives Dalim in his tomb. Thus, Dalim revives at night and dies in the morning. One day, Dalim Kumar awakes and sees the princess, his fiancée, in the pavilion, and they embrace. The prince tells the princess about the necklace, and she promises to fetch it and give it to him. After Dalim falls into a sleep again, the princess disguise herself as a barber woman and goes to queen Duo's palace. With a child in tandem, the princess convinces Duo to let the child play with the necklace. After fulfilling her task, the princess takes the necklace back to Dalim Kumar. He awakes and embraces his fiancée, thanking her for her help. The next day, Dalim Kumar and the princess enter his father's city to let him know his son is alive, and to punish the perfidious queen.
In a tale collected by author Mary Frere with the title Chundun Rajah, seven princes marry seven wives, who mistreat their sister-in-law, the princes' sister, except the seventh prince's wife. The women spread rumours about the princess until her brothers expel her from home. As a last humiliation, they shout at the princess to not return home until she marries Chundun Rajah ("King Sandlewood"), and when she does, to set wooden stools for them. The princess is given some food for the road, and finds a Rakshas's house. The Rakshas's pets, a little cat and a little dog, ask for some food and in returns let the princess take some of the Rakshas's antimony and saffron. Later, the princes finds a large tomb in the middle of the jungle, and enters it. The story then explains that the tomb belongs to Chundun Rajah: his family laid his body in the tomb, and, though many months have passed, his body has not decayed, because he comes alive at night and dies in the morning, and this only a Brahmin know. One night, Chundun Rajah wakes up and sees the princess. They tell each other their stories. Chundun Rajah marries the princess with the blessing of his Brahmin friend, and, one day, explains the origin of his malaise to the princess: a flying peri fell in love with Chundun Rajah, but he refused her advances, and, in vengeance, the peri stole the Chundun Har ("sandlewood necklace") that stored the youth's life within. In time, the princess gives birth to a boy, but, due to worry for her husband's state, she begins to fall ill. Their Brahmin friends suggests she seeks shelter with her relatives-in-law (Chundun Rajah's mother and sister), and to sit on a marble slab in their garden, which was Chundun's favourite. The princess takes her son and goes to her mother-in-law's palace to sit on the marble slab. Chundun Rajah's sisters notice her presence and go to talk to her, and notice that the little boy was very reminiscent of their dead brother. They take the princess and her son and give her a house to live in. Days pass, and Chundun Rajah's sisters hear some voices coming from the princess's house, and pay her a visit: they see their brother, Chundun Rajah, alive and well, and playing with his son. After a joyous reunion, Chundun Rajah tells them of the peri and the necklace. Some time later, Chundun Kumar is playing with his son in his wife's house, and the flying peris come in unseen, even the one wearing his necklace. Chundun's son sees that specific peri and tears off the necklace from her neck, making its beads fall to the ground. The peris fly out of the house, while the princess gathers the beads, rebuild the necklace and puts it on her husband's neck, ending his curse once and for all. Later, the princess invite her own brothers and their wives to her wedding to Chundun Rajah. Remembering her sisters-in-law's mocking remark, the princess has six of them sat on wooden stools, while the only one that was kind to her is given a better stool.
In a tale collected by Sunity Devi, Maharani of Coochbehar, with the title The Dead Prince, an astrologer has a sister. His sister gives birth to a girl and, after six days, asks her brother to predict her daughter's future - since, on the sixth day after birth, one's own future is written on their forehead by the Creator. The astrologer prophecizes that she will marry a dead man. Trying to avoid this fate, the girl's mother takes her daughter after she is 12 or 13 years old and wanders through a forest. Meanwhile, a Maharajah has two wives, a first Maharani with a son named Dalim Kumar, and a second Maharani, with no son. The second Maharani hates her step-son. One day, the prince is found dead, apparently he drowned while in the castle's grounds. The second Maharani suggests her husband burn the prince's body, but the boy's grieving mother asks her husband to build a palace to house the prince's body, with his instruments and provisions for 10 years. The Maharajah fulfills her request. Back to the girl and her mother, they are still wandering through forests and jungles, and the girl says she is thirsty. The girl stops to rest by a tree, while her mother goes in front of her to find any water source. They get separated: the mother thinks she lost her daughter and returns home, while the girl reaches the palace in the jungle. While she is there, one evening, the prince awakes and sees her. Days, months pass, and the girl and prince begin to like each other and marry. One day, the girl, now a woman, asks the prince his story. He tells that an astrologer predicted at the time of his birth his destiny as a great ruler, if he lived, and gave his father a necklace (which was "his life"), with a warning to not allow anyone wear it around their neck. So, to protect his son, the Maharajah places the necklace in a golden box and hid in the depths of a pool in the palace. However, the Maharajah's second wife, who also knew of the necklace, and ordered the fisherman to catch the fish that swallowed the golden box. The second Maharani stole the necklace and wore it around her neck - and it has been like this since then: whenever she wears the necklace in the morning, the prince dies, but come night, she takes off the necklace and the prince is alive. After hearing the story, the prince's wife, then, promises to get back the necklace. Some time later, some of the Maharajah's huntsmen and sportsmen report back to him that the prince's palace is haunted, since they hear a woman's voice and a baby's cry. The Maharajah ponders that, if his son was alive, he would have married and fathered a child at that time, but dismisses the huntsmen's concerns. Back to the prince's wife, she takes her child, disguises herself as a poor woman ("naptini") and goes to her father-in-law's palace to hire herself as a servant to the second Maharani. She has the Maharani play with her child, while she paints her feet, and the baby plays with the necklace. The prince's wife steals the necklace and rushes back to Dalim Kumar's palace to give him. Later, Dalim Kumar is visited by his father and mother, who rejoice that their son is alive. The prince suggests they throw the necklace to the depths of the ocean. Finally, the girl's mother learns of her daughter's survival and her story, and thanks her brother for his prediction.
In a tale from Assam, titled A Dead Husband, a man named Bidhata ("destiny") rules over fate. After his sister gives birth to a girl, Bidhata predicts that the girl shall have no want of food and drink, but she shall marry a dead husband. Trying to avoid this fate, Bidhata's sisters take her daughter and wander off. They reach a large, uninhabited palace on the way, and the girl is impelled inside it, leaving her mother outside the palace door. Inside, the girl cries due to being separated from her mother, but, at night, a handsome youth appears to her. The youth assuages her fears, and tells her he will die in the morning. The girl becomes a woman, and lives with the youth. One day, the youth explains he is a prince; his mother placed a necklace on his neck; after his mother died, his father remarried, and his new step-mother hated the prince and stole his necklace, causing him to fall into a death-like sleep immediately. The prince's step-mother placed the necklace in a water jug, and he wishes someone can retrieve the necklace. The prince's wife takes their child and goes to her father-in-law's palace to steal the necklace. She enters service as a maid, and wins the queen's trust. After some time, she takes back the necklace and rushes back to her husband. He is given the necklace and comes alive again. The prince goes back to his father and tells him the whole story. The king executes his wife, and welcomes his son and daughter-in-law.
See also
Momotaro
The Sleeping Prince (fairy tale)
Sleeping Beauty
Snow White
Syair Bidasari
Udea and her Seven Brothers
Uriko-hime
References
Indian fairy tales
Fictional princesses
Female characters in fairy tales
Sleep in mythology and folklore
ATU 400-459
Infanticide | Princess Aubergine | [
"Biology"
] | 9,738 | [
"Behavior",
"Sleep",
"Sleep in mythology and folklore"
] |
71,554,558 | https://en.wikipedia.org/wiki/Minoxidil%20sulfate | Minoxidil sulfate, also known as minoxidil sulfate ester or minoxidil N-O-sulfate, is an active metabolite of minoxidil (Rogaine, Loniten, others) and is the active form of this agent. Minoxidil acts as a prodrug of minoxidil sulfate. Minoxidil sulfate is formed from minoxidil via sulfotransferase enzymes, with the predominant enzyme responsible, at least in hair follicles, being SULT1A1. Minoxidil sulfate acts as a potassium channel opener, among other actions, and has vasodilating, hypotensive, and trichogenic or hypertrichotic (hair growth-promoting) effects. Its mechanism of action in terms of hair growth is still unknown, although multiple potential mechanisms have been implicated.
Minoxidil sulfate is a sulfate ester of minoxidil, not a sulfate salt of the compound. However, minoxidil sulfate forms an inner salt, which makes it more hydrophobic than minoxidil. This is in contrast to most sulfate esters, which are usually more hydrophilic than their non-ester forms. The bioactivation of minoxidil into minoxidil sulfate is very unusual and is among the only known instances of sulfation producing a more active drug form. Normally, sulfation tends to inactivate drugs by reducing their biological activity and increasing their excretion.
Minoxidil sulfate is highly unstable in aqueous solutions and alcohol-containing solvents, with a half-life of 6hours in aqueous solutions and a further much lower half-life in alcohol-containing solvents. This has served as a limiting factor in its potential pharmaceutical use and therapeutic effectiveness. Moreover, minoxidil sulfate has a 40% higher molecular weight than minoxidil, and this may reduce its absorption into the scalp. In any case, a minoxidil sulfate-based topical formulation has been investigated for the treatment of scalp hair loss. Additionally, minoxidil-sulfate-based topical formulations appear to be available for medical use in some parts of the world, for instance in Brazil.
References
Amine oxides
Aminopyrimidines
Antihypertensive agents
Hair loss medications
Human drug metabolites
1-Piperidinyl compounds
Potassium channel openers
Sulfate esters
Vasodilators | Minoxidil sulfate | [
"Chemistry"
] | 512 | [
"Chemicals in medicine",
"Amine oxides",
"Functional groups",
"Human drug metabolites"
] |
71,554,903 | https://en.wikipedia.org/wiki/Chuanyi%20Wang | Chuanyi Wang is a Chinese American, environmental chemistry scientist, academic, and an author. He is a Distinguished Professor and Academic Dean at the School of Environmental Science and Engineering at the Shaanxi University of Science & Technology. He is recognized for his research in environmental photocatalysis, environmental materials, surface/interface chemistry, nanomaterials, and pollution controlling.
Wang is the author and editor of two books, Recent Research Developments in Physical Chemistry: Surfaces And Interfaces of Nanostructured Systems and
Encyclopedia of Surface and Colloid Science.
Wang is a Fellow of Royal Society of Chemistry, and International Association of Advanced Materials (IAAM).
Education
Born in China on July 25, 1966, Wang graduated with Undergraduate Diplomas in Chemistry from Yancheng Teachers University in 1986 and Soochow University in 1991. He completed his PhD in 1998 from Technical Institute of Physics and Chemistry, Chinese Academy of Sciences.
Career
After completing his PhD in 1998, Wang held the Alexander von Humboldt Research Fellowship at the Free University Berlin and Institute for Solar Energy Research in Germany from 1999 to 2000. Between 2001 and 2006, he held the appointment of Research Associate and post-doctoral Research Associate at Tufts University. Following this appointment, he occupied the position of Research Assistant Professor at University of Missouri-Kansas City for two years. Starting from 2008 till 2009, he joined the University of Missouri-Kansas City as an Adjunct PhD Faculty. From 2010 to 2017, he served as a Distinguished Professor of Chinese Academy of Sciences (CAS). Currently, he holds the appointment of Honorary Professor at Wuhan University since 2014 and a Visiting Scientist at Tufts from 2019. He holds an appointment as a Distinguished Professor in the department of Environmental Science and Engineering at Shaanxi University of Science & Technology.
As of 2021, Wang is serving as an Academic Dean at School of Environmental Science and Engineering in Shaanxi University of Science & Technology. He served as a Director of Laboratory of Environmental Sciences and Technology, XJIPC and Vice-Director of Key Laboratory of Functional Materials & Devices for Special Environments of CAS.
Research
Wang has authored more than 270 publications. Wang's research work spans on environmental remediation, eco-materials, and surface/interface chemistry, and catalysis focused on nanosized metals and semiconductors.
Photocatalysis
Wang's research on photocatalysis is significant in reducing contaminants. He studied the selective photocatalytic N2 fixation induced by the nitrogen vacancies and indicated that Photocatalytic N2 fixation supported by nitrogen vacancies (NVs) leads to improved graphitic carbon nitride (g-C3N4).
Wang's research work focuses on the performance of nanostructured TiO2 particles. He conducted a comparative study that aimed to characterize the performance of TiO2 particles created in three different ways. The results from the study concluded that TiO2 nanoparticles prepared from organic precursors demonstrated an increased photocatalytic activity. Based on this method, Wang developed a method to uniformly distribute doped species like metal ions in semiconductor photocatalyst matrix.
Wang presented an in-depth view into the effectiveness of photocatalytic production under carbon vacancies. The findings suggested that Photocatalytic H2O2 production at Graphitic carbon nitrides (g-C3N4) carries the possibility to increase by 14 times with the carbon vacancies. He also studied the role of oxygen vacancies in the photocatalytic removal of NO under visible light. The study demonstrated that oxygen vacancies carry the potential to support selective photoreduction of NO to N2 and hinder the production of more toxic nitrogen dioxide.
Pollution Controlling
Wang's research characterized the importance of heavy metal adsorption by clay minerals. In a study conducted in 2019, he highlighted the primary adsorption mechanisms of the clay minerals like halloysite, bentonite, and attapulgite. This study reveals how wastewater contamination can be tackled with the utilization of clay mineral adsorbents.
Wang also focused his research on the removal of microplastics from the environment. In a recent study, he reviewed the removal methods, mechanisms, advantages of the efficient methods as well as the disadvantages of many microplastics removal methods.
Nanoparticles
Wang has extensively carried out research on nanoparticles and its implications for the environment. He formulated and characterized chitosan–poly(vinyl alcohol)/bentonite nanocomposites. The study of adsorption of Hg(II) ions by nanocomposites revealed that they carry high adsorption capacity for mercury ions, and can promote the adsorption selectivity of the nanocomposites.
Wang reviewed the interaction between silver nanoparticles and other nanoparticles. Discarded into the aquatic environment via waste or intentional release, the silver nanoparticles can lead to adverse effects on the aquatic life. With his study, it was revealed that Titanium oxide nanoparticles help in reducing the toxicity and dissolution of silver nanoparticles.
Surface/interface chemistry
Wang conducted a surface chemistry study on typical photocatalytic material TiO2 by means of second-order nonlinear laser spectroscopy, clarifying the distribution characteristics of hydroxyl groups on the surface of TiO2, and the properties of probe molecules methanol and acetic acid, as well as their adsorption modes and competitive adsorption with water molecules.
Awards and honors
1998 - Humboldt Research Fellowship, Alexander von Humboldt Foundation
1998 – Excellent Prize, President Scholarship of Chinese Academy of Sciences
2011 – Science and Technology Award, Chinese Materials Research Society
2014 – Tianshan Award of China, Government of Xinjiang Uygur Autonomous Region
2016 – China's Overseas Chinese Community Contribution Award (Innovative Talents), China Association for Science and Technology (CAST)
2018- Fellow of Royal Society of Chemistry (FRSC)
2020 – Named in the top 2 % of the most influential scientists in the world in their scientific career, 2021 (Physical Chemistry, #169 in 2020). Stanford University
2020 – IAAM Scientist Award, International Association of Advanced Materials
2022 - Fellow of International Association of Advanced Materials
2022 - Named in the top 2 % of the most influential scientists in the world in their scientific career, 2022 (Physical Chemistry, #87 in 2021). Stanford University
Bibliography
Books/chapters
Encyclopedia of Surface and Colloid Science, Third Edition (2002)
Recent Research Developments in Physical Chemistry: Surfaces And Interfaces of Nanostructured Systems (2017)
Selected articles
Wang, C. Y., Bahnemann, D. W., & Dohrmann, J. K. (2000). A novel preparation of iron-doped TiO2 nanoparticles with enhanced photocatalytic activity. Chemical Communications, (16), 1539–1540.
Wang, C. Y., Böttcher, C., Bahnemann, D. W., & Dohrmann, J. K. (2003). A comparative study of nanometer sized Fe (III)-doped TiO2 photocatalysts: synthesis, characterization and activity. Journal of Materials Chemistry, 13(9), 2322–2329.
Chen, S., Slattum, P., Wang, C., & Zang, L. (2015). Self-assembly of perylene imide molecules into 1D nanostructures: methods, morphologies, and applications. Chemical reviews, 115(21), 11967-11998.
Dong, G., Ho, W., & Wang, C. (2015). Selective photocatalytic N2 fixation dependent on gC3N4 induced by nitrogen vacancies. Journal of Materials Chemistry A, 3(46), 23435-23441.
Li, S., Dong, G., Hailili, R., Yang, L., Li, Y., Wang, F., ... & Wang, C. (2016). Effective photocatalytic H2O2 production under visible light irradiation at g-C3N4 modulated by carbon vacancies. Applied Catalysis B: Environmental, 190, 26–35.
References
Living people
1966 births
Environmental scientists
Scientists from Jiangsu
Soochow University (Suzhou) alumni
Academic staff of Shaanxi University of Science and Technology
University of Missouri–Kansas City faculty
People's Republic of China emigrants to the United States
Fellows of the Royal Society of Chemistry
21st-century American chemists | Chuanyi Wang | [
"Environmental_science"
] | 1,766 | [
"American environmental scientists",
"Environmental scientists"
] |
71,555,641 | https://en.wikipedia.org/wiki/Thom%E2%80%93Sebastiani%20Theorem | In complex analysis, a branch of mathematics, the Thom–Sebastiani Theorem states: given the germ defined as where are germs of holomorphic functions with isolated singularities, the vanishing cycle complex of is isomorphic to the tensor product of those of . Moreover, the isomorphism respects the monodromy operators in the sense: .
The theorem was introduced by Thom and Sebastiani in 1971.
Observing that the analog fails in positive characteristic, Deligne suggested that, in positive characteristic, a tensor product should be replaced by a (certain) local convolution product.
References
Theorems in complex analysis | Thom–Sebastiani Theorem | [
"Mathematics"
] | 128 | [
"Theorems in mathematical analysis",
"Mathematical analysis",
"Theorems in complex analysis",
"Mathematical analysis stubs"
] |
71,555,642 | https://en.wikipedia.org/wiki/Promethium%28III%29%20bromide | Promethium(III) bromide is an inorganic compound, with the chemical formula of PmBr3. It is radioactive salt. It is a crystal of the hexagonal crystal system, with the space group of P63/mc (No. 176).
Preparation
Promethium(III) bromide can be obtained by reacting hydrogen bromide and promethium(III) oxide:
Pm2O3 + 6 HBr —500°C→ 2 PmBr3 + 3 H2O
Promethium(III) bromide hydrate cannot be heated to form its anhydrous form. Instead it decomposes in water to form promethium oxybromide:
PmBr3 + H2O(g) → PmOBr + 2 HBr
References
Bromides
Promethium compounds
Lanthanide halides | Promethium(III) bromide | [
"Chemistry"
] | 175 | [
"Bromides",
"Salts"
] |
71,557,105 | https://en.wikipedia.org/wiki/Buford%20Dam | Buford Dam is a dam in Buford, Georgia which is located at the southern end of Lake Lanier, a reservoir formed by the construction of the dam in 1956. The dam itself is managed by the United States Army Corps of Engineers.
The dam is made of earth and concrete, supplemented by three saddle dikes, and was built to provide a water source for the Atlanta area, power homes, and prevent flooding of the Chattahoochee River.
Electricity from the dam is marketed by the Southeastern Power Administration.
Construction
Congress authorized construction of the dam in 1946, and in 1949 the federal government gave the State of Georgia $750,000 (equivalent to $ in ) towards the building of the dam and accompanying powerhouse.
On March 1, 1950, a groundbreaking ceremony was held, which included dignitaries such as Atlanta mayor William B. Hartsfield. The United States Army Corps of Engineers oversaw the construction of the dam.
During construction, land was bought in the area that would become the reservoir. Homes, churches, graveyards, and all other structures that would float were removed or burned. Many residents in the reservoir area fought the buying of their homes with unsuccessful civil lawsuits.
The powerhouse required crews to use dynamite to blast a U-shaped space through granite rock structures to hollow out an area for the powerhouse and release gates. During the construction of the dam, Johnnie Callahan died during a rockslide when cutting an intake tunnel into the face of the granite rock wall.
On February 1, 1956, the dam was completed when the sluice gates were closed and Lake Lanier began to fill. Unit 2 began operation on June 20, 1957, Unit 3 on July 26, 1957, and Unit 1 on October 10, 1957. The dam was dedicated on October 9, 1957. The power plant went into full-scale operation in July 1958, and the lake reached its intended level on August 1 of that year.
Operation
When water is released from the dam's turbines, several sirens sound as well as an AM warning broadcast.
The dam also has a diameter sluice which can be used to allow water to bypass the turbines.
Downriver from the dam is a trout breeding hatchery, which is one of the southernmost hatcheries for trout, due to the cool temperature of the water that the dam releases.
Powerhouse
The powerhouse at the dam has three generators: the main generator, a small 7.5 megawatt generator which runs constantly, and two 60 megawatt generators that run twice daily during times of peak electricity demand. The powerhouse provides of electricity annually to the metro Atlanta area. Control of the Buford Dam generators is done remotely from Carters Dam near Ellijay, Georgia via a microwave signal. The power generated is delivered to Georgia Power.
The powerhouse is cooled by the temperature of the water running through the dam, which is approximately year-round.
In 2002, the US Army Corps of Engineers spent $8.5 million to provide upgrades to the powerhouse.
Goats
Because the earthen slopes on the outer side of the dam exceed 40% grade (21.8°, 1 in 2.5) and contain rocks and drop off points, they are too steep and unsafe to practically maintain by a landscaping crew. To address this, the US Army Corps of Engineers use goats to maintain the grass and vegetation on the slope as it is more economically viable than alternatives. Goats have been used since the 1970s for this purpose, and there are sixteen goats that maintain the grounds, known as the "Chew Crew". There is also a donkey onsite that is used to protect the goats from coyotes.
References
1957 establishments in Georgia (U.S. state)
Buford, Georgia
Dams completed in 1957
Dams in Georgia (U.S. state)
Energy infrastructure completed in 1957
Engineering projects
Hydroelectric power plants in Georgia (U.S. state)
United States Army Corps of Engineers | Buford Dam | [
"Engineering"
] | 785 | [
"Engineering units and formations",
"United States Army Corps of Engineers",
"nan"
] |
71,557,608 | https://en.wikipedia.org/wiki/Aphanotorulus%20phrixosoma | Aphanotorulus phrixosoma is a dubious species of catfish in the family Loricariidae. It is native to South America, where it occurs in the upper Amazon River basin. The species reaches SL. It is believed to be a facultative air-breather.
A. phrixosoma was originally described as Plecostomus phrixosoma by Henry Weed Fowler in 1940, although it was transferred to the genus Squaliforma (now considered invalid) after the genus' designation by I. J. H. Isbrücker, I. Seidel, J. Michels, E. Schraml, and A. Werner in 2001. In 2004, Jonathan W. Armbruster classified the species within Hypostomus instead of Squaliforma. In 2016, following a review of Isorineloricaria and Aphanotorulus by C. Keith Ray and Armbruster (both of Auburn University), the species was reclassified as a member of Aphanotorulus.
A. phrixosoma is of questionable validity, as it is currently known to originate only from a single specimen that is believed by Ray and Armbruster to be a hybrid between Aphanotorulus horridus and Aphanotorulus unicolor. This is due to the fact that it was collected in an area where A. horridus and A. unicolor are sympatric, and because extensive sampling efforts near the type locality have yielded no additional specimens.
References
Hypostominae
Fish described in 1940
Species known from a single specimen | Aphanotorulus phrixosoma | [
"Biology"
] | 337 | [
"Individual organisms",
"Species known from a single specimen"
] |
71,558,241 | https://en.wikipedia.org/wiki/Syzkaller | Syzkaller is a software fuzzing framework that has been used for fuzzing the Linux kernel. It also supports other kernels.
As of 2021, the Syzkaller dashboard showed hundreds of bugs in the Linux kernel.
References
External links
Syzkaller GitHub repository
Security testing tools | Syzkaller | [
"Engineering"
] | 65 | [
"Software engineering",
"Software engineering stubs"
] |
71,558,587 | https://en.wikipedia.org/wiki/Instagram%20face | Instagram face is a beauty standard based on the filters and influencers popular on Instagram. An "Instagram face" has catlike eyes, long lashes, a small nose, high cheekbones, full lips, and a blank expression. Digital filters manipulate photographs and video to create an idealized image that, according to critics, has resulted in an unrealistic and homogeneous beauty standard. According to Jia Tolentino, the face is "distinctly white but ambiguously ethnic". The face has been described as a racial composite of different peoples.
While based on digital filters, the look is achieved in person using heavy applications of makeup or cosmetic surgery. Plastic surgery, Botox injections, and injectable filler have significantly increased in popularity since the rise of digital filters. Influencers market makeup products designed to recreate the look. In 2018, Americans underwent 7 million neurotoxin injections and 2.5 million filler injections and spent $16.5 billion on cosmetic surgery. 92% of the latter was performed on women. Botox usage has also been on the rise.
In 2019, The New Yorker referred to this phenomenon as "Instagram Face," identifying Kim Kardashian as its "patient zero." Similarly, her younger sister Kylie Jenner significantly impacted the trend with her 2015 lip filler confession, which acted as a catalyst, introducing Juvéderm to a new generation.
In 2024, cosmetic surgeon Paul Banwell said, "People used to come to see me asking to look like a particular celebrity, but many patients come to me now wanting to look like the filtered version of themselves." The increasing popularity of cosmetic surgeries towards a homogeneous ideal has resulted in the emergence of the "goopcore" sub-genre of body horror. The sub-genre combines graphic violence with body modifications from the beauty industry. Allie Rowbottom's goopcore novel Aesthetica centers around an influencer attempting to undo years of plastic surgery with a new experimental procedure.
See also
Filter (social media)
Body dysmorphic disorder
References
Face
Social media
Human appearance
Face | Instagram face | [
"Technology"
] | 429 | [
"Computing and society",
"Social media"
] |
71,560,254 | https://en.wikipedia.org/wiki/HD%20208741 | HD 208741, also known as HR 8380, is a yellowish-white hued star located in the southern circumpolar constellation Octans. It has an apparent magnitude of 5.91, making it faintly visible to the naked eye. Parallax measurements place it at a distance of 211 light years, and it is currently receding with a heliocentric radial velocity of .
HD 208741 has a 10th magnitude K-type main-sequence companion separated by . Together, they make up a wide binary system designated collectively as CPD−76°1542. Sir John Herschel, the discoverer of the pair, noted the primary to be a probable spectroscopic binary.
This object has a stellar classification of F3 III, indicating that it is a slightly evolved F-type star. Gaia Data Release 3 models it to be a dwarf that is 81.3% through its main sequence lifetime. At present it has 1.52 times the mass of the Sun and a slightly enlarged radius of due to its evolved state. It radiates at 12.9 times the luminosity of the Sun from its photosphere at an effective temperature of . HD 208741 has a metallicity twice the Sun's, making it metal enriched. It is estimated to be 1.1 billion years old, and is spinning with a projected rotational velocity of .
References
F-type giants
K-type main-sequence stars
208741
PD-76 01542
108849
8380
Octantis, 66
Double stars
Octans | HD 208741 | [
"Astronomy"
] | 319 | [
"Octans",
"Constellations"
] |
71,560,354 | https://en.wikipedia.org/wiki/Agaricus%20annae | Agaricus annae is a species of mushroom in the genus Agaricus. This species is in the family Agaricaceae.
References
annae
Fungi described in 1951
Fungus species | Agaricus annae | [
"Biology"
] | 39 | [
"Fungi",
"Fungus species"
] |
71,560,400 | https://en.wikipedia.org/wiki/Agaricus%20alabamensis | Agaricus alabamensis is a North American species of mushroom in the genus Agaricus. This species is in the family Agaricaceae. Its spores have a dark chocolate color.
References
alabamensis
Fungi of North America
Fungus species | Agaricus alabamensis | [
"Biology"
] | 53 | [
"Fungi",
"Fungus species"
] |
44,331,841 | https://en.wikipedia.org/wiki/YubiKey | The YubiKey is a hardware authentication device manufactured by Yubico to protect access to computers, networks, and online services that supports one-time passwords (OTP), public-key cryptography, authentication, and the Universal 2nd Factor (U2F) and FIDO2 protocols developed by the FIDO Alliance. It allows users to securely log into their accounts by emitting one-time passwords or using a FIDO-based public/private key pair generated by the device. YubiKey also allows storing static passwords for use at sites that do not support one-time passwords. Google, Amazon, Microsoft, Twitter, and Facebook use YubiKey devices to secure employee accounts as well as end-user accounts. Some password managers support YubiKey. Yubico also manufactures the Security Key, a similar lower-cost device with only FIDO2/WebAuthn and FIDO/U2F support.
The YubiKey implements the HMAC-based one-time password algorithm (HOTP) and the time-based one-time password algorithm (TOTP), and identifies itself as a keyboard that delivers the one-time password over the USB HID protocol. A YubiKey can also present itself as an OpenPGP card using 1024, 2048, 3072 and 4096-bit RSA (for key sizes over 2048 bits, GnuPG version 2.0 or higher is required) and elliptic curve cryptography (ECC) p256, p384 and more, depending on version, allowing users to sign, encrypt and decrypt messages without exposing the private keys to the outside world. Also supported is the PKCS#11 standard to emulate a PIV smart card. This feature allows code signing of Docker images as well as certificate-based authentication for Microsoft Active Directory and SSH.
Founded in 2007 by former CEO now Chief Evangelist Stina Ehrensvärd, Yubico is a Public company with offices in Santa Clara, CA, Bellevue, WA, and Stockholm, Sweden. Yubico CTO, Jakob Ehrensvärd, is the lead author of the original strong authentication specification that became known as Universal 2nd Factor (U2F).
YubiKey released the YubiKey 5 series in 2018, which adds support for FIDO2.
History
Yubico was founded in 2007 and began offering a Pilot Box for developers in November of that year. The original YubiKey product was shown at the annual RSA Conference in April 2008, and a more robust YubiKey II model was launched in 2009. Yubico's explanation of the name "YubiKey" is that it derives from the phrase "your ubiquitous key", and that "yubi" is the Japanese word for finger.
YubiKey II and later models have two "slots" available, for storing two distinct configurations with separate AES secrets and other settings. When authenticating the first slot is used by only briefly pressing the button on the device, while the second slot gets used when holding the button for 2 to 5 seconds.
In 2010, Yubico began offering the YubiKey OATH and YubiKey RFID models. The YubiKey OATH added the ability to generate 6- and 8-character one-time passwords using protocols from the Initiative for Open Authentication (OATH), in addition to the 32-character passwords used by Yubico's own OTP authentication scheme. The YubiKey RFID model included the OATH capability plus also included a MIFARE Classic 1k radio-frequency identification chip, though that was a separate device within the package that could not be configured with the normal Yubico software over a USB connection.
Yubico announced the YubiKey Nano in February 2012, a miniaturized version of the standard YubiKey which was designed so it would fit almost entirely inside a USB port and only expose a small touch pad for the button. Most later models of the YubiKey have also been available in both standard and "nano" sizes.
2012 also saw the introduction of the YubiKey Neo, which improved upon the previous YubiKey RFID product by implementing near-field communication (NFC) technology and integrating it with the USB side of the device. The YubiKey Neo (and Neo-n, a "nano" version of the device) are able to transmit one-time passwords to NFC readers as part of a configurable URL contained in a NFC Data Exchange Format (NDEF) message. The Neo is also able to communicate using the CCID smart-card protocol in addition to USB HID (human interface device) keyboard emulation. The CCID mode is used for PIV smart card and OpenPGP support, while USB HID is used for the one-time password authentication schemes.
In 2014, the YubiKey Neo was updated with FIDO Universal 2nd Factor (U2F) support. Later that year, Yubico released the FIDO U2F Security Key, which specifically included U2F support but none of the other one-time password, static password, smart card, or NFC features of previous YubiKeys. At launch, it was correspondingly sold at a lower price point of just $18, compared to $25 for the YubiKey Standard ($40 for the Nano version), and $50 for the YubiKey Neo ($60 for Neo-n). Some of the pre-release devices issued by Google during FIDO/U2F development reported themselves as "Yubico WinUSB Gnubby (gnubby1)".
In April 2015, the company launched the YubiKey Edge in both standard and nano form factors. This slotted in between the Neo and FIDO U2F products feature-wise, as it was designed to handle OTP and U2F authentication, but did not include smart card or NFC support.
The YubiKey 4 family of devices was first launched in November 2015, with USB-A models in both standard and nano sizes. The YubiKey 4 includes most features of the YubiKey Neo, including increasing the allowed OpenPGP key size to 4096 bits (vs. the previous 2048), but dropped the NFC capability of the Neo.
At CES 2017, Yubico announced an expansion of the YubiKey 4 series to support a new USB-C design. The YubiKey 4C was released on February 13, 2017. On Android OS over the USB-C connection, only the one-time password feature is supported by the Android OS and YubiKey, with other features not currently supported including Universal 2nd Factor (U2F). A 4C Nano version became available in September 2017.
In April 2018, the company brought out the Security Key by Yubico, their first device to implement the new FIDO2 authentication protocols, WebAuthn (which reached W3C Candidate Recommendation status in March) and Client to Authenticator Protocol (CTAP). At launch, the device is only available in the "standard" form factor with a USB-A connector. Like the previous FIDO U2F Security Key, it is blue in color and uses a key icon on its button. It is distinguished by a number "2" etched into the plastic between the button and the keyring hole. It is also less expensive than the YubiKey Neo and YubiKey 4 models, costing $20 per unit at launch because it lacks the OTP and smart card features of those previous devices, though it retains FIDO U2F capability.
Product features
A list of the primary features and capabilities of the YubiKey products.
ModHex
When being used for one-time passwords and stored static passwords, the YubiKey emits characters using a modified hexadecimal alphabet which is intended to be as independent of system keyboard settings as possible. This alphabet is referred to as ModHex and consists of the characters "cbdefghijklnrtuv", corresponding to the hexadecimal digits "0123456789abcdef".
Since YubiKeys use raw keyboard scan codes in USB HID mode, there can be problems when using the devices on computers that are set up with different keyboard layouts, such as Dvorak. ModHex was created to avoid conflicts between different keyboard layouts. It only uses characters that are located in the same place on most Latin alphabet keyboards, but is still 16 characters, allowing it to be used in place of hexadecimal. Alternatively, this issue can be addressed by using operating system features to temporarily switch to a standard US keyboard layout (or similar) when using one-time passwords. However, YubiKey Neo and later devices can be configured with alternate scan codes to match layouts that aren't compatible with the ModHex character set.
This problem only applies to YubiKey products in HID mode, where it must emulate keyboard input. U2F authentication in YubiKey products bypasses this problem by using the alternate U2FHID protocol, which sends and receives raw binary messages instead of keyboard scan codes. CCID mode acts as a smart card reader, which does not use HID protocols at all.
Security issues
YubiKey 4 closed-sourcing concerns
Most of the code that runs on a YubiKey is closed source. While Yubico has released some code for industry standard functionality like PGP and HOTP it was disclosed that as of the 4th generation of the product this is not the same code that the new units ship with. Because new units are permanently firmware locked at the factory it is not possible to compile the open source code and load it on the device manually, a user must trust that the code on a new key is authentic and secure.
Code for other functionality such as U2F, PIV and Modhex is entirely closed source.
On May 16, 2016, Yubico CTO Jakob Ehrensvärd responded to the open-source community's concerns with a blog post saying that "we, as a product company, have taken a clear stand against implementations based on off-the-shelf components and further believe that something like a commercial-grade AVR or ARM controller is unfit to be used in a security product."
Techdirt founder Mike Masnick strongly criticized this decision, saying "Encryption is tricky. There are almost always vulnerabilities and bugs -- a point we've been making a lot lately. But the best way to fix those tends to be getting as many knowledgeable eyes on the code as possible. And that's not possible when it's closed source."
ROCA vulnerability in certain YubiKey 4, 4C, and 4 Nano devices
In October 2017, security researchers found a vulnerability (known as ROCA) in the implementation of RSA keypair generation in a cryptographic library used by a large number of Infineon security chips, as used in a wide range of security keys and security token products (including YubiKey). The vulnerability allows an attacker to reconstruct the private key by using the public key. All YubiKey 4, YubiKey 4C, and YubiKey 4 Nano devices within the revisions 4.2.6 to 4.3.4 were affected by this vulnerability. Yubico remedied this issue in all shipping YubiKey 4 devices by switching to a different key generation function and offered free replacements for any affected keys until March 31, 2019. In some cases, the issue can be bypassed by generating new keys outside of the YubiKey and importing them onto the device.
OTP password protection on YubiKey NEO
In January 2018, Yubico disclosed a moderate vulnerability where password protection for the OTP functionality on the YubiKey NEO could be bypassed under certain conditions. The issue was corrected as of firmware version 3.5.0, and Yubico offered free replacement keys to any user claiming to be affected until April 1, 2019.
Reduced initial randomness on certain FIPS series devices
In June 2019, Yubico released a security advisory reporting reduced randomness in FIPS-certified devices with firmware version 4.4.2 and 4.4.4 (there is no version 4.4.3), shortly after power-up. Security keys with reduced randomness may leave keys more easily discovered and compromised than expected. The issue affected the FIPS series only, and then only certain scenarios, although FIPS ECDSA usage was "at higher risk". The company offered free replacements for any affected keys.
Infineon ECDSA Private Key Recovery
In September 2024, security researchers from NinjaLab discovered a cryptographic flaw in Infineon chips that would allow a person to clone a Yubikey if an attacker gained physical access to it. The security vulnerability permanently affects all Yubikeys prior to firmware update 5.7. Yubico rated the issue as "moderate" citing the need for an attacker to have physical access to the key, expensive equipment, and advanced cryptographic and technical knowledge.
Social activism
In 2018, Yubico gave away free YubiKeys with laser engraved logos to new WIRED and ArsTechnica subscribers.
Yubico provided 500 YubiKeys to protesters during the 2019–2020 Hong Kong protests. The company states the decision was based on their mission to protect vulnerable Internet users and work with free speech supporters.
See also
FIDO Alliance
Nitrokey
OpenPGP card
References
External links
2007 establishments in California
Authentication methods
Companies based in Palo Alto, California
Companies based in Seattle
Companies based in Stockholm
Computer access control
Computer companies established in 2007
Cryptographic hardware
Technology companies based in the San Francisco Bay Area | YubiKey | [
"Engineering"
] | 2,823 | [
"Cybersecurity engineering",
"Computer access control"
] |
44,333,212 | https://en.wikipedia.org/wiki/NGC%206584 | NGC 6584 is a globular cluster in the constellation Telescopium that lies near Theta Arae and is 45000 light-years distant. It is an Oosterhoff type I cluster, and contains at least 69 variable stars, most of which are RR Lyrae variables: 46 stars were identified as RRab variables; 15 as RRc variables, 1 RRe variable, 4 eclipsing binaries and 3 long period variables. NGC 6584 is about 4 kpc from the Galactic Center and about 2.7 kpc from the Galactic plane.
As is typical for metal-poor globular clusters, NGC 6584 has an enhanced concentration of alpha elements relative to iron.
References
External links
Globular clusters
6584 | NGC 6584 | [
"Astronomy"
] | 158 | [
"Telescopium",
"Constellations"
] |
44,337,770 | https://en.wikipedia.org/wiki/Optica%20Optics%20Software | Optica is an optical design program used for the design and analysis of both imaging and illumination systems. It works by ray tracing the propagation of rays through an optical system. It performs polarization ray-tracing, non-sequential ray-tracing, energy calculations, and optimization of optical systems in three-dimensional space. It also performs symbolic modeling of optical systems, diffraction, interference, wave-front, and Gaussian beam propagation calculations. In addition to conducting simulations of optical designs, Optica is used by scientists to create illustrations of the simulated results in publications. Some examples of Optica being used in simulations and illustrations include holography, x-ray optics, spectrometers, Cerenkov radiation, microwave optics, nonlinear optics, scattering, camera design, extreme ultraviolet lithography simulations, telescope optics, laser design, ultrashort pulse lasers, eye models, solar concentrators and Ring Imaging CHerenkov (RICH) particle detectors.
History
Optica was originally developed by Donald Barnhart of Urbana, Illinois, USA, and has been in continual development since 1994. Wolfram Research first sold the original version as a Mathematica application. From 2005 to 2009, Optica Software was sold by iCyt Mission Technology Inc, Champaign, Illinois (renamed Sony Biotechnology Inc in 2010). At iCyt, Optica2 was renamed as Rayica, and Wavica and LensLab were also developed. Later Rayica-Wavica was combined and named back to Optica3. Since 2009, Optica Software has been a subsidiary of Barnhart Optical Research LLC.
References
External links
Optica Software Website
Wolfram Research Optics Page
Wolfram Research Optica3
Optical software
Physics software | Optica Optics Software | [
"Physics"
] | 348 | [
"Physics software",
"Computational physics"
] |
44,337,776 | https://en.wikipedia.org/wiki/TDLS | TDLS, shortened from Tunneled Direct Link Setup, is "a seamless way to stream media and other data faster between devices already on the same Wi-Fi network." Devices using it communicate directly with one another, without involving the wireless network's router.
Wi-Fi Alliance added certification for TDLS in 2012. It describes this feature as technology that enables devices to link directly to one another when connected to a traditional Wi-Fi network. Wi-Fi CERTIFIED TDLS devices can set up secure links and transfer data directly between them. TDLS-linked devices benefit from an optimized connection to do things such as streaming video or synching content, without burdening the network as a whole.
The IEEE has endorsed this as the IEEE 802.11z standard.
Google's Cast protocol used by Chromecast utilizes TDLS to initiate screen mirroring.
See also
Wi-Fi Direct
References
Wi-Fi
Wi-Fi Direct | TDLS | [
"Technology"
] | 192 | [
"Computing stubs",
"Wireless networking",
"Wi-Fi",
"Computer network stubs"
] |
44,338,182 | https://en.wikipedia.org/wiki/Epsilon%20Composite | Epsilon Composite is a French company created in 1987 by Stephane LULL, its current CEO. Its revenue in 2021 was 33.5 M€ with 230 employees.
Epsilon Composite designs and produces a wide range of Carbon-fiber-reinforced polymer (CFRP) products for various applications:
Manufacturing and printing machines (flexography and textile industries)
Energy (oil & gas offshore exploitation, wind turbines)
Civil Engineering
Camera support equipment (tripods)
Automotive and leisure applications
Aerospace (Airbus and Flying Whales Tier-1 supplier)
The main production process used by the company are pultrusion and its pull-winding variant.
The production site is located in Gaillan, France.
The company is regularly listed among the “key players in Carbon Fiber Reinforced Plastics Market” in independent market reports.
In 2021, one of the company's projects was selected as JEC Innovation Awards finalist in the Aerospace category.
Epsilon Composite won the 2023 Global Industrie Award for the development of an innovative composite overmolding process.
References
External links
Composite materials
Aerospace
Privately held companies of France
French companies established in 1987 | Epsilon Composite | [
"Physics"
] | 219 | [
"Aerospace",
"Composite materials",
"Materials",
"Space",
"Spacetime",
"Matter"
] |
44,338,719 | https://en.wikipedia.org/wiki/Taniyama%20group | In mathematics, the Taniyama group is a group that is an extension of the absolute Galois group of the rationals by the Serre group. It was introduced by using an observation by Deligne, and named after Yutaka Taniyama. It was intended to be the group scheme whose representations correspond to the (hypothetical) CM motives over the field Q of rational numbers.
References
Algebraic groups
Langlands program | Taniyama group | [
"Mathematics"
] | 86 | [
"Langlands program",
"Number theory"
] |
44,338,782 | https://en.wikipedia.org/wiki/Serre%20group | In mathematics, the Serre group S is the pro-algebraic group whose representations correspond to CM-motives over the algebraic closure of the rationals, or to polarizable rational Hodge structures with abelian Mumford–Tate groups. It is a projective limit of finite dimensional tori, so in particular is abelian. It was introduced by . It is a subgroup of the Taniyama group.
There are two different but related groups called the Serre group, one the connected component of the identity in the other. This article is mainly about the connected group, usually called the Serre group but sometimes called the connected Serre group. In addition one can define Serre groups of algebraic number fields, and the Serre group is the inverse limit of the Serre groups of number fields.
Definition
The Serre group is the projective limit of the Serre groups of SL of finite Galois extensions of the rationals, and each of these groups SL is a torus, so is determined by its module of characters, a finite free Z-module with an action of the finite Galois group Gal(L/Q). If L* is the algebraic group with L*(A) the units of A⊗L, then L* is a torus with the same dimension as L, and its characters can be identified with integral functions on Gal(L/Q).
The Serre group SL is a quotient of this torus L*, so can be described explicitly in terms of the module X*(SL) of rational characters. This module of rational characters can be identified with the integral functions λ on Gal(L/Q) such that
(σ−1)(ι+1)λ = (ι+1)(σ−1)λ = 0
for all σ in Gal(L/Q), where ι is complex conjugation. It is acted on by the Galois group.
The full Serre group S can be described similarly in terms of its module X*(S) of rational characters. This module of rational characters can be identified with the locally constant integral functions λ on Gal(/Q) such that
(σ−1)(ι+1)λ = (ι+1)(σ−1)λ = 0
for all σ in Gal(/Q), where ι is complex conjugation.
References
Algebraic groups
Langlands program | Serre group | [
"Mathematics"
] | 484 | [
"Langlands program",
"Number theory"
] |
44,339,074 | https://en.wikipedia.org/wiki/Atmospheric-pressure%20photoionization | Atmospheric pressure photoionization (APPI) is a soft ionization method used in mass spectrometry (MS) usually coupled to liquid chromatography (LC). Molecules are ionized using a vacuum ultraviolet (VUV) light source operating at atmospheric pressure (105 Pa), either by direct absorption followed by electron ejection or through ionization of a dopant molecule that leads to chemical ionization of target molecules. The sample is usually a solvent spray that is vaporized by nebulization and heat. The benefit of APPI is that it ionizes molecules across a broad range of polarity and is particularly useful for ionization of low polarity molecules for which other popular ionization methods such as electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) are less suitable. It is also less prone to ion suppression and matrix effects compared to ESI and APCI and typically has a wide linear dynamic range. The application of APPI with LC/MS is commonly used for analysis of petroleum compounds, pesticides, steroids, and drug metabolites lacking polar functional groups and is being extensively deployed for ambient ionization particularly for explosives detection in security applications.
Instrument configuration
The figure shows the main components of an APPI source: a nebulizer probe which can be heated to 350–500 °C, an ionization region with a VUV photon source, and an ion-transfer region under intermediate pressure that introduces ions into the MS analyzer. The analyte(s) in solution from the HPLC flows into the nebulizer at a flow rate that can range from μL/min to mL/min range. The liquid flow is vaporized by nebulization and heat. The vaporized sample then enters into the radiation zone of the VUV source. Sample ions then enter into the MS interface region, frequently a capillary through the combination of a decreasing pressure gradient and electric fields.
APPI has been commercially developed as dual ionization sources more commonly with APCI, but also with ESI.
Ionization mechanisms
The photoionization mechanism is simplified under vacuum conditions: photon absorption by the analyte molecule, leading to electron ejection, forming a molecular radical cation, M•+. This process is similar to electron ionization common to GC/MS, except that the ionization process is soft, i.e., less fragmentation. In the atmospheric region of an LC/MS system, the ionization mechanism becomes more complex. The unpredictable fate of ions is generally detrimental to LC/MS analysis, but like most processes, once they are better understood, these properties can be exploited to enhance performance. For example, the role of dopant in APPI, first developed and patented for the atmospheric ion source of ion mobility spectrometry (IMS), was adapted to APPI for LC/MS. The basic APPI mechanisms can be summarized by the following scheme:
Direct positive ion APPI
Dopant or solvent-assisted positive ion APPI
The fundamental process in photoionization is the absorption of a high-energy photon by the molecule and subsequent ejection of an electron. In direct APPI, this process occurs for the analyte molecule, forming the molecular radical cation M•+. The analyte radical cation can be detected as M•+ or it can react with surrounding molecules and be detected as another ion. The most common reaction is the abstraction of a hydrogen atom from the abundant solvent to form the stable [M+H]+ cation, which is usually the observed ion.
In dopant-APPI (or photoionization-induced APCI), a quantity of photoionizable molecules (e.g., toluene or acetone) is introduced into the sample stream to create a source of charge carriers. Use of a photoionizable solvent can also achieve the same effect. The dopant or solvent ions can then react with neutral analyte molecules via proton transfer or charge exchange reactions. The above table simplifies the dopant process. In fact, there may be extensive ion-molecule chemistry between dopant and solvent before the analyte becomes ionized. APPI can also produce negative ions by creating a high abundance of thermal electrons from dopant or solvent ionization or by photons striking metal surfaces in the ionization source. The cascade of reactions that can lead to M− or dissociative negative ions [M-X]− often involve O2 as an electron charge carrier. Examples of negative ionization mechanisms include:
Direct or dopant-assisted negative ion APPI
History
Photoionization has a long history of use in mass spectrometry experiments, though mostly for research purposes and not for sensitive analytical applications. Pulsed lasers have been used for non-resonant multiphoton ionization (MPI), resonance-enhanced MPI (REMPI) using tunable wavelengths, and single-photon ionization using sum frequency generation in non-linear media (usually gas cells). Non-laser sources of photoionization include discharge lamps and synchrotron radiation. The former sources were not adaptable to high sensitivity analytical applications because of low spectral brightness in the former case and large "facility-size" in the latter case. Meanwhile, photoionization has been used for GC detection and as a source for ion mobility spectrometry for many years suggesting the potential for use in mass spectrometry.
The first development of APPI for LC/MS was reported by Robb, Covey, and Bruins and by Syage, Evans, and Hanold in 2000. APPI sources were commercialized shortly thereafter by Syagen Technology and made available for most commercial MS systems and by Sciex for their line of MS instruments. Concurrent to the development of APPI was a similar use of a VUV source for low pressure photoionization (LPPI) by Syage and coworkers that accepted atmospheric pressure gas phase samples but stepped down the pressure for ionization to about 1 torr (~100 Pa) before further pressure reduction for introduction into a MS analyzer. This photoionization method is well suited as an interface between gas chromatography (GC) and MS.
Advantages
APPI is most used for LC/MS although it has recently found widespread use in ambient applications such as detection of explosives and narcotics compounds for security applications using ion mobility spectrometry. Compared to the more commonly used predecessor ionization sources ESI and APCI, APPI ionizes a broader range of compounds with the benefit increasing toward the non-polar end of the scale. It also has relatively low susceptibility to ion suppression and matrix effects, which makes APPI very effective in detecting compounds quantitatively in complex matrices. APPI has other advantages including a broader linear range and dynamic range than ESI as seen by the example in the left figure. It is also generally more selective than APCI with reduced background ion signals as shown in the right figure. This latter example also highlights the benefit of APPI vs. ESI in that the HPLC conditions were for non-polar normal-phase in this case using n-hexane solvent. ESI requires polar solvents and further hexane could pose an ignition hazard for ESI and APCI that use high voltages. APPI works well under normal-phase conditions since many of the solvents are photoionizable and serve as dopant ions, which allows specialized applications such as separation of enantiomers (right figure).
Regarding applicability to a range of HPLC flow rates, the signal level of analytes by APPI has been observed to saturate and even decay at higher solvent flow rates (above 200 μl/min), and therefore, much lower flow rates are recommended for APPI than for ESI and APCI. This has been suggested to be due to absorption of photons by the increasing density of solvent molecules., However, this leads to the benefit that APPI can extend to very low flow rates (e.g., 1 μL/min domain) allowing for effective use with capillary LC and capillary-electrophoresis.
Application
The application of APPI with LC/MS is commonly used for analysis of low polarity compounds such as petroleums, polyatomic hydrocarbons, pesticides, steroids, lipids, and drug metabolites lacking polar functional groups. Excellent review articles can be found in the References.
APPI has also been effectively applied for ambient ionization applications lending itself to several practical configurations. One configuration termed desorption APPI (DAPPI) was developed by Haapala et al. and is pictured in the figure here. This device has been applied to the analysis of drugs of abuse in various solid phases, drug metabolites and steroids in urine, pesticides in plant material, etc. APPI has also been interfaced to a DART (direct analysis in real time) source and shown for non-polar compounds such as steroids and pesticides to enhance signal by up to an order of magnitude for N2 flow, which is preferred for DART because it is significantly cheaper and easier to generate then the higher performing use of He. Commercial APPI sources have also been adapted to accept an insertable sampling probe that can deliver or liquid or solid sample to the nebulizer for vaporization and ionization. This configuration is similar to atmospheric solid analysis probe (ASAP) that is based on the use of APCI and therefore is referred to as APPI-ASAP. The benefits of APPI-ASAP vs. APCI-ASAP are similar to those observed in LC/MS, namely higher sensitivity to lower polarity compounds and less background signal for samples in complex matrices. Though ambient ionization has experienced a renaissance in the last decades, it has been used in the security industry for many decades, for example in swab detections at airports. The swabs collect condensed phase material from surfaces and are then inserted into a thermal desorber and ionizer assembly that then flows into the ion detector, which in most cases are an ion mobility spectrometer (IMS), but in later cases have been MS analyzers. A picture of a swab-APPI-IMS system used in airports and other security venues is given in the left figure
In fact, a swab-APPI-MS system designed for explosives and narcotics detection for security applications performs very well for all types of ambient analysis using a sampling wand and swab (right figure). A particular demonstration (unpublished) showed excellent sensitivity and specificity for detection of pesticide compounds on a variety of fruits and vegetables showing detection limits for 37 priority pesticides ranging from 0.02 to 3.0 ng well below safe limits.
See also
Atmospheric pressure chemical ionization
Chemical ionization
Corona discharge
Electrospray ionization
Secondary electrospray ionization
References
Concepts in physics
Mass spectrometry
Ion source | Atmospheric-pressure photoionization | [
"Physics",
"Chemistry"
] | 2,259 | [
"Spectrum (physical sciences)",
"Instrumental analysis",
"Mass",
"Ion source",
"Mass spectrometry",
"nan",
"Matter"
] |
44,339,334 | https://en.wikipedia.org/wiki/Rimose | Rimose is an adjective used to describe a surface that is cracked or fissured.
The term is often used in describing crustose lichens. A rimose surface of a lichen is sometimes contrasted to the surface being areolate. Areolate is an extreme form of being rimose, where the cracks or fissures are so deep that they create island-like pieces called areoles, which look the "islands" of mud on the surface of a dry lake bed. Rimose and areolate are contrasted with being verrucose, or "warty". Verrucose surfaces have warty bumps which are distinct, but not separated by cracks.
In mycology the term describes mushrooms whose caps crack in a radial pattern, as commonly found in the genera Inocybe and Inosperma.
References
Biology terminology
English words
Lichens | Rimose | [
"Biology"
] | 178 | [
"nan"
] |
44,339,868 | https://en.wikipedia.org/wiki/Contraves%20Cora | The Cora was a digital fire-control system designed by Hungarian-Swiss Peter Tóth and produced by the Swiss company Contraves.
Development
Peter Tóth started the design of Cora-1 in 1957. The system was intended for anti-aircraft fire direction with the Swiss Army. However, Cora-1 turned out to be too slow and too bulky for this application. It was programmed for other applications by programmers including Heinz Lienhard. One copy of the system was used at the École Polytechnique Fédérale de Lausanne (EPFL) for cartography, and was put on display during Expo 64. The unit was rediscovered in storage in 2011, and is now on display at the Musée Bolo, in the Computer Science department of the EPFL. Cora-1-was one of the first fully transistorized digital computers built in Switzerland according to the Von Neumann architecture.
An improved version of this computer was developed subsequently by a team led by Swiss engineer Peter Blum. Cora-2 was successfully used for anti-aircraft fire direction being compact enough to fit into the corresponding mobile control unit.
The Musée Bolo met with Peter Tóth and released several videos around his work on the Cora.
References
External links
Discovery of Two Historical Computers in Switzerland: Zuse Machine M9 and Contraves Cora and Discovery of Unknown Documents on the Early History of Computing at the ETH Archives, Making the History of Computing Relevant , Springer 2013
Schweizer Transistorrechner für militärische und zivile Zwecke, IT Magazine 2012/01
Military computers
Artillery components
Artillery operation
Applications of control engineering
Ballistics
Military electronics
Computer-related introductions in 1978 | Contraves Cora | [
"Physics",
"Technology",
"Engineering"
] | 335 | [
"Applied and interdisciplinary physics",
"Control engineering",
"Artillery components",
"Ballistics",
"Applications of control engineering",
"Components"
] |
44,340,383 | https://en.wikipedia.org/wiki/Kawasaki%27s%20Riemann%E2%80%93Roch%20formula | In differential geometry, Kawasaki's Riemann–Roch formula, introduced by Tetsuro Kawasaki, is the Riemann–Roch formula for orbifolds. It can compute the Euler characteristic of an orbifold.
Kawasaki's original proof made a use of the equivariant index theorem. Today, the formula is known to follow from the Riemann–Roch formula for quotient stacks.
References
Tetsuro Kawasaki. The Riemann-Roch theorem for complex V-manifolds. Osaka J. Math., 16(1):151–159, 1979
Theorems in differential geometry
Theorems in algebraic geometry
See also
Riemann–Roch-type theorem | Kawasaki's Riemann–Roch formula | [
"Mathematics"
] | 146 | [
"Theorems in differential geometry",
"Theorems in algebraic geometry",
"Theorems in geometry"
] |
44,342,518 | https://en.wikipedia.org/wiki/Multidimensional%20network | In network theory, multidimensional networks, a special type of multilayer network, are networks with multiple kinds of relations.
Increasingly sophisticated attempts to model real-world systems as multidimensional networks have yielded valuable insight in the fields of social network analysis, economics, urban and international transport, ecology, psychology, medicine, biology, commerce, climatology, physics, computational neuroscience, operations management, and finance.
Terminology
The rapid exploration of complex networks in recent years has been dogged by a lack of standardized naming conventions, as various groups use overlapping and contradictory terminology to describe specific network configurations (e.g., multiplex, multilayer, multilevel, multidimensional, multirelational, interconnected). To fully leverage the dataset information on the directional nature of the communications, some authors consider only direct networks without any labels on vertices, and introduce the definition of edge-labeled multigraphs which can cover many multidimensional situations. The term "fully multidimensional" has also been used to refer to a multipartite edge-labeled multigraph. Multidimensional networks have also recently been reframed as specific instances of multilayer networks.
In this case, there are as many layers as there are dimensions, and the links between nodes within each layer are simply all the links for a given dimension.
Definition
Unweighted multilayer networks
In elementary network theory, a network is represented by a graph in which is the set of nodes and the links between nodes, typically represented as a tuple of nodes . While this basic formalization is useful for analyzing many systems, real world networks often have added complexity in the form of multiple types of relations between system elements. An early formalization of this idea came through its application in the field of social network analysis (see, e.g., and papers on relational algebras in social networks) in which multiple forms of social connection between people were represented by multiple types of links.
To accommodate the presence of more than one type of link, a multidimensional network is represented by a triple , where is a set of dimensions (or layers), each member of which is a different type of link, and consists of triples with and .
Note that as in all directed graphs, the links and are distinct.
By convention, the number of links between two nodes in a given dimension is either 0 or 1 in a multidimensional network. However, the total number of links between two nodes across all dimensions is less than or equal to .
Weighted multilayer networks
In the case of a weighted network, this triplet is expanded to a quadruplet , where is the weight on the link between and in the dimension .
Further, as is often useful in social network analysis, link weights may take on positive or negative values. Such signed networks can better reflect relations like amity and enmity in social networks. Alternatively, link signs may be figured as dimensions themselves, e.g. where and This approach has particular value when considering unweighted networks.
This conception of dimensionality can be expanded should attributes in multiple dimensions need specification. In this instance, links are n-tuples . Such an expanded formulation, in which links may exist within multiple dimensions, is uncommon but has been used in the study of multidimensional time-varying networks.
General formulation in terms of tensors
Whereas unidimensional networks have two-dimensional adjacency matrices of size , in a multidimensional network with dimensions, the adjacency matrix becomes a multilayer adjacency tensor, a four-dimensional matrix of size . By using index notation, adjacency matrices can be indicated by , to encode connections between nodes and , whereas multilayer adjacency tensors are indicated by , to encode connections between node in layer and node in layer . As in unidimensional matrices, directed links, signed links, and weights are all easily accommodated by this framework.
In the case of multiplex networks, which are special types of multilayer networks where nodes can not be interconnected with other nodes in other layers, a three-dimensional matrix of size with entries is enough to represent the structure of the system by encoding connections between nodes and in layer .
Multidimensional network-specific definitions
Multi-layer neighbors
In a multidimensional network, the neighbors of some node are all nodes connected to across dimensions.
Multi-layer path length
A path between two nodes in a multidimensional network can be represented by a vector r in which the th entry in r is the number of links traversed in the th dimension of . As with overlapping degree, the sum of these elements can be taken as a rough measure of a path length between two nodes.
Network of layers
The existence of multiple layers (or dimensions) allows to introduce the new concept of network of layers, peculiar of multilayer networks. In fact, layers might be interconnected in such a way that their structure can be described by a network, as shown in the figure.
The network of layers is usually weighted (and might be directed), although, in general, the weights depends on the application of interest. A simple approach is, for each pair of layers, to sum all of the weights in the connections between their nodes to obtain edge weights that can be encoded into a matrix . The rank-2 adjacency tensor, representing the underlying network of layers in the space is given by
where is the canonical matrix with all components equal to zero except for the entry corresponding to row and column , that is equal to one. Using the tensorial notation, it is possible to obtain the (weighted) network of layers from the multilayer adjacency tensor as .
Centrality measures
Degree
In a non-interconnected multidimensional network, where interlayer links are absent, the degree of a node is represented by a vector of length . Here is an alternative way to denote the number of layers in multilayer networks. However, for some computations it may be more useful to simply sum the number of links adjacent to a node across all dimensions. This is the overlapping degree: . As with unidimensional networks, distinction may similarly be drawn between incoming links and outgoing links.
If interlayer links are present, the above definition must be adapted to account for them, and the multilayer degree is given by
where the tensors and have all components equal to 1. The heterogeneity in the number of connections of a node across the different layers can be taken into account through the participation coefficient.
Versatility as multilayer centrality
When extended to interconnected multilayer networks, i.e. those systems where nodes are connected across layers, the concept of centrality is better understood in terms of versatility. Nodes that are not central in each layer might be the most important for the multilayer systems in certain scenarios. For instance, this is the case where two layers encode different networks with only one node in common: it is very likely that such a node will have the highest centrality score because it is responsible for the information flow across layers.
Eigenvector versatility
As for unidimensional networks, eigenvector versatility can be defined as the solution of the eigenvalue problem given by , where Einstein summation convention is used for sake of simplicity. Here, gives the multilayer generalization of Bonacich's eigenvector centrality per node per layer. The overall eigenvector versatility is simply obtained by summing up the scores across layers as .
Katz versatility
As for its unidimensional counterpart, the Katz versatility is obtained as the solution of the tensorial equation , where , is a constant smaller than the largest eigenvalue and is another constant generally equal to 1. The overall Katz versatility is simply obtained by summing up the scores across layers as .
HITS versatility
For unidimensional networks, the HITS algorithm has been originally introduced by Jon Kleinberg to rate Web Pages. The basic assumption of the algorithm is that relevant pages, named authorities, are pointed by special Web pages, named hubs. This mechanism can be mathematically described by two coupled equations which reduce to two eigenvalue problems. When the network is undirected, Authority and Hub centrality are equivalent to eigenvector centrality.
These properties are preserved by the natural extension of the equations proposed by Kleinberg to the case of interconnected multilayer networks, given by
and , where indicates the transpose operator, and indicate hub and authority centrality, respectively. By contracting the hub and authority tensors, one obtains the overall versatilities as and , respectively.
PageRank versatility
PageRank, originally introduced to rank web pages, can also be considered as a measure of centrality for interconnected multilayer networks.
It is worth remarking that PageRank can be seen as the steady-state solution of a special Markov process on the top of the network. Random walkers explore the network according to a special transition matrix and their dynamics is governed by a random walk master equation. It is easy to show that the solution of this equation is equivalent to the leading eigenvector of the transition matrix.
Random walks have been defined also in the case of interconnected multilayer networks and edge-colored multigraphs (also known as multiplex networks). For interconnected multilayer networks, the transition tensor governing the dynamics of the random walkers within and across layers is given by , where is a constant, generally set to 0.85, is the number of nodes and is the number of layers or dimensions. Here, might be named Google tensor and is the rank-4 tensor with all components equal to 1.
As its unidimensional counterpart, PageRank versatility consists of two contributions: one encoding a classical random walk with rate and one encoding teleportation across nodes and layers with rate .
If we indicate by the eigentensor of the Google tensor , denoting the steady-state probability to find the walker in node and layer , the multilayer PageRank is obtained by summing up over layers the eigentensor:
Triadic closure and clustering coefficients
Like many other network statistics, the meaning of a clustering coefficient becomes ambiguous in multidimensional networks, due to the fact that triples may be closed in different dimensions than they originated. Several attempts have been made to define local clustering coefficients, but these attempts have highlighted the fact that the concept must be fundamentally different in higher dimensions: some groups have based their work off of non-standard definitions, while others have experimented with different definitions of random walks and 3-cycles in multidimensional networks.
Community discovery
While cross-dimensional structures have been studied previously, they fail to detect more subtle associations found in some networks. Taking a slightly different take on the definition of "community" in the case of multidimensional networks allows for reliable identification of communities without the requirement that nodes be in direct contact with each other.
For instance, two people who never communicate directly yet still browse many of the same websites would be viable candidates for this sort of algorithm.
Modularity maximization
A generalization of the well-known modularity maximization method for community discovery has been originally proposed by Mucha et al. This multiresolution method assumes a three-dimensional tensor representation of the network connectivity within layers, as for edge-colored multigraphs, and a three-dimensional tensor representation of the network connectivity across layers. It depends on the resolution parameter and the weight of interlayer connections. In a more compact notation, making use of the tensorial notation, modularity can be written as , where , is the multilayer adjacency tensor, is the tensor encoding the null model and the value of components of is defined to be 1 when a node in layer belongs to a particular community, labeled by index , and 0 when it does not.
Tensor decomposition
Non-negative matrix factorization has been proposed to extract the community-activity structure of temporal networks. The multilayer network is represented by a three-dimensional tensor , like an edge-colored multigraph, where the order of layers encode the arrow of time. Tensor factorization by means of Kruskal decomposition is thus applied to to assign each node to a community across time.
Statistical inference
Methods based on statistical inference, generalizing existing approaches introduced for unidimensional networks, have been proposed. Stochastic block model is the most used generative model, appropriately generalized to the case of multilayer networks.
As for unidimensional networks, principled methods like minimum description length can be used for model selection in community detection methods based on information flow.
Structural reducibility
Given the higher complexity of multilayer networks with respect to unidimensional networks, an active field of research is devoted to simplify the structure of such systems by employing some kind of dimensionality reduction.
A popular method is based on the calculation of the quantum Jensen-Shannon divergence between all pairs of layers, which is then exploited for its metric properties to build a distance matrix and hierarchically cluster the layers. Layers are successively aggregated according to the resulting hierarchical tree and the aggregation procedure is stopped when the objective function, based on the entropy of the network, gets a global maximum. This greedy approach is necessary because the underlying problem would require to verify all possible layer groups of any size, requiring a huge number of possible combinations (which is given by the Bell number and scales super-exponentially with the number of units). Nevertheless, for multilayer systems with a small number of layers, it has been shown that the method performs optimally in the majority of cases.
Other multilayer network descriptors
Degree correlations
The question of degree correlations in unidimensional networks is fairly straightforward: do nodes of similar degree tend to connect to each other? In multidimensional networks, what this question means becomes less clear. When we refer to a node's degree, are we referring to its degree in one dimension, or collapsed over all? When we seek to probe connectivity between nodes, are we comparing the same nodes across dimensions, or different nodes within dimensions, or a combination? What are the consequences of variations in each of these statistics on other network properties? In one study, assortativity was found to decrease robustness in a duplex network.
Path dominance
Given two multidimensional paths, r and s, we say that r dominates s if and only if: and such that .
Shortest path discovery
Among other network statistics, many centrality measures rely on the ability to assess shortest paths from node to node. Extending these analyses to a multidimensional network requires incorporating additional connections between nodes into the algorithms currently used (e.g., Dijkstra's). Current approaches include collapsing multi-link connections between nodes in a preprocessing step before performing variations on a breadth-first search of the network.
Multidimensional distance
One way to assess the distance between two nodes in a multidimensional network is by comparing all the multidimensional paths between them and choosing the subset that we define as shortest via path dominance: let be the set of all paths between and . Then the distance between and is a set of paths such that such that dominates . The length of the elements in the set of shortest paths between two nodes is therefore defined as the multidimensional distance.
Dimension relevance
In a multidimensional network , the relevance of a given dimension (or set of dimensions) for one node can be assessed by the ratio: .
Dimension connectivity
In a multidimensional network in which different dimensions of connection have different real-world values, statistics characterizing the distribution of links to the various classes are of interest. Thus it is useful to consider two metrics that assess this: dimension connectivity and edge-exclusive dimension connectivity. The former is simply the ratio of the total number of links in a given dimension to the total number of links in every dimension: . The latter assesses, for a given dimension, the number of pairs of nodes connected only by a link in that dimension: .
Burst detection
Burstiness is a well-known phenomenon in many real-world networks, e.g. email or other human communication networks. Additional dimensions of communication provide a more faithful representation of reality and may highlight these patterns or diminish them. Therefore, it is of critical importance that our methods for detecting bursty behavior in networks accommodate multidimensional networks.
Diffusion processes on multilayer networks
Diffusion processes are widely used in physics to explore physical systems, as well as in other disciplines as social sciences, neuroscience, urban and international transportation or finance. Recently, simple and more complex diffusive processes have been generalized to multilayer networks. One result common to many studies is that diffusion in multiplex networks, a special type of multilayer system, exhibits two regimes: 1) the weight of inter-layer links, connecting layers each other, is not high enough and the multiplex system behaves like two (or more) uncoupled networks; 2) the weight of inter-layer links is high enough that layers are coupled each other, raising unexpected physical phenomena. It has been shown that there is an abrupt transition between these two regimes.
In fact, all network descriptors depending on some diffusive process, from centrality measures to community detection, are affected by the layer-layer coupling. For instance, in the case of community detection, low coupling (where information from each layer separately is more relevant than the overall structure) favors clusters within layers, whereas high coupling (where information from all layer simultaneously is more relevant than the each layer separately) favors cross-layer clusters.
Random walks
As for unidimensional networks, it is possible to define random walks on the top of multilayer systems. However, given the underlying multilayer structure, random walkers are not limited to move from one node to another within the same layer (jump), but are also allowed to move across layers (switch).
Random walks can be used to explore a multilayer system with the ultimate goal to unravel its mesoscale organization, i.e. to partition it in communities, and have been recently used to better understand navigability of multilayer networks and their resilience to random failures, as well as for exploring efficiently this type of topologies.
In the case of interconnected multilayer systems, the probability to move from a node in layer to node in layer can be encoded into the rank-4 transition tensor and the discrete-time walk can be described by the master equation
where indicates the probability of finding the walker in node in layer at time .
There are many different types of walks that can be encoded into the transition tensor , depending on how the walkers are allowed to jump and switch. For instance, the walker might either jump or switch in a single time step without distinguishing between inter- and intra-layer links (classical random walk), or it can choose either to stay in the current layer and jump, or to switch layer and then jump to another node in the same time step (physical random walk). More complicated rules, corresponding to specific problems to solve, can be found in the literature. In some cases, it is possible to find, analytically, the stationary solution of the master equation.
Classical diffusion
The problem of classical diffusion in complex networks is to understand how a quantity will flow through the system and how much time it will take to reach the stationary state. Classical diffusion in multiplex networks has been recently studied by introducing the concept of supra-adjacency matrix, later recognized as a special flattening of the multilayer adjacency tensor. In tensorial notation, the diffusion equation on the top of a general multilayer system can be written, concisely, as
where is the amount of diffusing quantity at time in node in layer . The rank-4 tensor governing the equation is the Laplacian tensor, generalizing the combinatorial Laplacian matrix of unidimensional networks. It is worth remarking that in non-tensorial notation, the equation takes a more complicated form.
Many of the properties of this diffusion process are completely understood in terms of the second smallest eigenvalue of the Laplacian tensor. It is interesting that diffusion in a multiplex system can be faster than diffusion in each layer separately, or in their aggregation, provided that certain spectral properties are satisfied.
Information and epidemics spreading
Recently, how information (or diseases) spread through a multilayer system has been the subject of intense research.
Multilayer network analysis software
Several software programs focusing on the analysis and visualization of multilayer networks have been introduced. Some popular solutions include multinet (C++ / Python / R), MuxViz (R), Pymnet (Python), with each software typically specializing in different analytical functions. However, most software currently face issues such as processing very large multilayer networks, while the interoperability between software also needs improvement.
References
Networks
Network theory | Multidimensional network | [
"Mathematics"
] | 4,319 | [
"Network theory",
"Mathematical relations",
"Graph theory"
] |
44,342,842 | https://en.wikipedia.org/wiki/Harborth%27s%20conjecture | In mathematics, Harborth's conjecture states that every planar graph has a planar drawing in which every edge is a straight segment of integer length. This conjecture is named after Heiko Harborth, and (if true) would strengthen Fáry's theorem on the existence of straight-line drawings for every planar graph. For this reason, a drawing with integer edge lengths is also known as an integral Fáry embedding. Despite much subsequent research, Harborth's conjecture remains unsolved.
Special classes of graphs
Although Harborth's conjecture is not known to be true for all planar graphs, it has been proven for several special kinds of planar graph.
One class of graphs that have integral Fáry embeddings are the graphs that can be reduced to the empty graph by a sequence of operations of two types:
Removing a vertex of degree at most two.
Replacing a vertex of degree three by an edge between two of its neighbors. (If such an edge already exists, the degree three vertex can be removed without adding another edge between its neighbors.)
For such a graph, a rational Fáry embedding can be constructed incrementally by reversing this removal process, re-inserting the vertices that were removed. Re-inserting a degree-two vertex uses the fact that the set of points that are at a rational distance from two given points are dense in the plane. Re-inserting a degree-three vertex uses the fact that, if three points have rational distance between one pair and square-root-of-rational distance between the other two pairs, then the points at rational distances from all three are again dense in the plane. The distances in such an embedding can be made into integers by scaling the embedding by an appropriate factor. Based on this construction, the graphs known to have integral Fáry embeddings include the bipartite planar graphs, (2,1)-sparse planar graphs, planar graphs of treewidth at most 3, and graphs of degree at most four that either contain a diamond subgraph or are not 4-edge-connected.
In particular, the graphs that can be reduced to the empty graph by the removal only of vertices of degree at most two (the 2-degenerate planar graphs) include both the outerplanar graphs and the series–parallel graphs. However, for the outerplanar graphs a more direct construction of integral Fáry embeddings is possible, based on the existence of infinite subsets of the unit circle in which all distances are rational.
Additionally, integral Fáry embeddings are known for each of the five Platonic solids.
Related conjectures
A stronger version of Harborth's conjecture, posed by , asks whether every planar graph has a planar drawing in which the vertex coordinates as well as the edge lengths are all integers. It is known to be true for 3-regular graphs, for graphs that have maximum degree 4 but are not 4-regular, and for planar 3-trees.
Another unsolved problem in geometry, the Erdős–Ulam problem, concerns the existence of dense subsets of the plane in which all distances are rational numbers. If such a subset existed, it would form a universal point set that could be used to draw all planar graphs with rational edge lengths (and therefore, after scaling them appropriately, with integer edge lengths). However, Ulam conjectured that dense rational-distance sets do not exist.
According to the Erdős–Anning theorem, infinite non-collinear point sets with all distances being integers cannot exist. This does not rule out the existence of sets with all distances rational, but it does imply that in any such set the denominators of the rational distances must grow arbitrarily large.
See also
Integer triangle, an integral Fáry embedding of the triangle graph
Matchstick graph, a graph that can be drawn planarly with all edge lengths equal to 1
Erdős–Diophantine graph, a complete graph with integer distances that cannot be extended to a larger complete graph with the same property
Euler brick, an integer-distance realization problem in three dimensions
References
Conjectures
Unsolved problems in graph theory
Planar graphs
Arithmetic problems of plane geometry | Harborth's conjecture | [
"Mathematics"
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"Mathematical problems"
] |
59,339,981 | https://en.wikipedia.org/wiki/Bowl%20Prechamber%20Ignition | Bowl Prechamber Ignition, abbreviated BPI, is a combustion process designed for Otto cycle engines running on an air-fuel mixture leaner than stochiometric . Its distinguishing feature is a special type of spark plug, capable of reliably igniting very lean air-fuel mixtures. This spark plug is called prechamber spark plug. The ignition electrodes of this spark plug are housed in a perforated enclosure, the prechamber. At the engine's compression stroke, some fuel (usually less than 5 % of the total injected fuel) is injected into the piston bowl; this fuel is then forced through the small holes into the prechamber due to the high pressure in the cylinder near top dead centre. Inside the prechamber spark plug, the air-fuel mixture is ignitable by the ignition spark. Flame jets occurring due to the small holes in the prechamber then ignite the air-fuel mixture in the main combustion chamber, that would not catch fire using a regular spark plug.
Bibliography
Maurice Kettner, Jürgen Fischer, Andreas Nauwerck, Jan Tribulowski, Ulrich Spicher, Amin Velji: The BPI Flame Jet Concept to Improve the Inflammation of Lean Burn Mixtures in Spark Ignited Engines. SAE. 2004. DOI 10.4271/2004-01-0035.
Richard van Basshuysen: Ottomotor mit Direkteinspritzung und Direkteinblasung: Ottokraftstoffe, Erdgas, Methan, Wasserstoff, 4th edition, Springer, Wiesbaden, 2017. . p. 58f.
Kurt Lohner, Herbert Müller (Autoren): Gemischbildung und Verbrennung im Ottomotor, in Hans List (Hrsg.): Die Verbrennungskramaschine, Band 6, Springer, Wien, 1967, , p. 285
Ignition systems
Engine components | Bowl Prechamber Ignition | [
"Technology"
] | 406 | [
"Engine components",
"Engines"
] |
59,340,033 | https://en.wikipedia.org/wiki/Robert%20T.%20Clubb | Robert Thompson Clubb is an American scientist. He a professor of chemistry, biochemistry, and molecular biology at University of California, Los Angeles.
Early life and education
Robert Thompson Clubb was born to surgical nurse Vera Alice Thompson of Yakima, Washington and Jerome M. Clubb a professor of history. Clubb has a sister. He earned a bachelor of science at University of Wisconsin. He completed a doctor of philosophy in biological chemistry at University of Michigan. His 1993 dissertation was titled Application and development of multi-dimensional NMR spectroscopic techniques to study protein structure in solution. Clubb's advisors and co-chairs of his thesis committee were Gerhard Wagner and Martha L. Ludwig. He received training in practical nuclear magnetic resonance spectroscopy from Venkataraman Thanabal. From 1993 to 1996, Clubb was a post-doctoral research fellow at the National Institutes of Health. His advisors were G. Marius Clore and Angela Gronenborn.
Career
Clubb is a professor of chemistry, biochemistry, and molecular biology at University of California, Los Angeles. He is the lab director of the Clubb Lab and co-director and staff researcher at the Nuclear Magnetic Resonance (NMR) Core Technology Center (DOE).
Personal life
Clubb is married to Joanna Hoffman Clubb. They reside in Culver City, California.
References
Living people
Year of birth missing (living people)
University of Wisconsin–Madison alumni
University of Michigan alumni
University of California, Los Angeles faculty
20th-century American chemists
21st-century American biochemists | Robert T. Clubb | [
"Chemistry"
] | 312 | [
"Structural biologists",
"Structural biology"
] |
59,340,777 | https://en.wikipedia.org/wiki/Vera%20Fischer%20%28mathematician%29 | Vera V. Fischer is a mathematician specializing in set theory, mathematical logic, and infinitary combinatorics. She is a privatdozent in the Kurt Gödel Research Center for Mathematical Logic at the University of Vienna.
Education and career
Fischer completed her doctorate in 2008 at York University in Canada. Her dissertation, The Consistency of Arbitrarily Large Spread between the Bounding and the Splitting Numbers, was supervised by Juris Steprāns.
Before joining the Kurt Gödel Research Center, she worked at TU Wien from 2014 to 2015, where she led a project under the Lise Meitner Programme of the Austrian Science Fund.
Recognition
In 2017, Fischer won the Start-Preis of the Austrian Science Fund.
In 2018, she won the Prize of the Austrian Mathematical Society.
References
External links
Home page
Year of birth missing (living people)
Living people
Women mathematicians
Mathematical logicians
Women logicians
Combinatorialists
York University alumni
Academic staff of TU Wien
Academic staff of the University of Vienna | Vera Fischer (mathematician) | [
"Mathematics"
] | 203 | [
"Mathematical logic",
"Combinatorialists",
"Combinatorics",
"Mathematical logicians"
] |
59,340,793 | https://en.wikipedia.org/wiki/Dallol%20%28hydrothermal%20system%29 | Dallol is a unique, terrestrial hydrothermal system around a cinder cone volcano in the Danakil Depression, northeast of the Erta Ale Range in Ethiopia. It is known for its unearthly colors and mineral patterns, and the very acidic fluids that discharge from its hydrothermal springs.
Etymology
The term Dallol was coined by the Afar people and means dissolution or disintegration, describing a landscape of green acid ponds and geysers (pH-values less than 1) and iron oxide, sulfur and salt desert plains.
Description
Dallol mountain has an area of about , and rises about above the surrounding salt plains. A circular depression near the centre is probably a collapsed crater. The southwestern slopes have water-eroded salt canyons, pillars, and blocks. There are numerous saline springs and fields of small fumaroles.
Numerous hot springs discharge brine and acidic liquid here. Small, widespread, temporary geysers produce cones of salt. The Dallol deposits include significant bodies of potash found directly at the surface. The yellow, ochre and brown colourings are the result of the presence of iron and other impurities. Older, inactive springs tend to be dark brown because of oxidation processes.
Formation
It was formed by the intrusion of basaltic magma into Miocene salt deposits and subsequent hydrothermal activity. Phreatic eruptions took place here in 1926, forming Dallol Volcano; numerous other eruption craters dot the salt flats nearby. These craters are the lowest known subaerial volcanic vents in the world, at or more below sea level. In October 2004, the shallow magma chamber beneath Dallol deflated and fed a magma intrusion southwards beneath the rift. The most recent signs of activity occurred in January 2011 in what may have been a degassing event from deep below the surface.
Physical properties
Dallol lies in the evaporitic plain of the Danakil Depression at the Afar Triangle, in the prolongation of the Erta Ale basaltic volcanic range. The intrusion of basaltic magma in the marine sedimentary sequence of Danakil resulted in the formation of a salt dome structure, where the hydrothermal system is hosted. The age of the hydrothermal system is unknown and the latest phreatic eruption that resulted in the formation of a diameter crater within the dome, took place in 1926. The wider area of Dallol is known as one of the driest and hottest places on the planet. It is also one of the lowest land points, lying below mean sea level. Other known hydrothermal features nearby Dallol are Gaet'Ale Pond and Black Lakes.
The hydrothermal springs of Dallol discharge anoxic, hyper-acidic (pH < 0), hyper-saline (almost 10 times more saline than seawater), high temperature (hotter than ) brines that contain more than 26 g/L of iron. The main gases emitted from the springs and fumaroles are carbon dioxide, hydrogen sulfide, nitrogen, sulfur dioxide; and traces of hydrogen, argon, and oxygen. Although several other hyper-acidic (pH < 2) volcanic systems exist, mainly found in crater lakes and hydrothermal sites, the pH values of Dallol decrease far below zero. The coexistence of such extreme physicochemical characteristics (pH, salinity, high temperature, lack of oxygen, etc.) render Dallol one of the very few ‘poly-extreme’ sites on Earth. This is why Dallol is a key system for astrobiological studies investigating the limits of life. Parts of the region are nearly sterile, except for a diverse array of "ultrasmall" archaea.
Dallol is highly dynamic; active springs go inactive and new springs emerge in new places in the range of days, and this is also reflected in the colors of the site that change with time, from white to green, lime, yellow, gold, orange, red, purple and ochre. In contrast to other hydrothermal systems known for their colorful pools (e.g. Grand Prismatic Spring), where the colors are generated by biological activity, the color palette of Dallol is produced by the inorganic oxidation of the abundant iron phases. Another fascinating feature of Dallol is the wide array of unusual mineral patterns such as salt-pillars, miniature geysers, water-lilies, flower-like crystals, egg-shaped crusts, and pearl-like spheres. The main mineral phases encountered at Dallol are halite, jarosite, hematite, akaganeite and other Fe-oxyhydroxides, gypsum, anhydrite, sylvite and carnallite.
Absence of life
In October 2019, a French-Spanish team of scientists published an article in Nature Ecology and Evolution that concludes that while the salt plains are teeming with halophilic microorganisms, there is no life in Dallol's multi-extreme ponds due to the combination of hyperacidic and hypersaline environments, and the abundance of magnesium (which catalyzes the denaturation of biomolecules). However another team reported for the first time evidence of life existing with these hot springs using a combination of morphological and molecular analyses. Ultra-small structures are shown to be entombed within mineral deposits, which are identified as members of the Order Nanohaloarchaea.
History
The Dallol area lies up to below sea level, and has been repeatedly flooded in the past when waters from the Red Sea have flowed into the depression. The last separation from the Red Sea was about 30,000 years ago.
The discovery of the volcano by the first European settlers certainly dates from the first colonization and expeditions in the region, in the 17th or 18th century. But the hostility of the depression, the unbearable heat which reigns there, and the dangers of the site (acid basins, toxic fumes), did not favour the exploration of the zones close to the crater. On the contrary, the Erta Ale was much more accessible, especially because the part of the rift where it is located (called the Erta Ale Range), is significantly higher. The last eruption of this phreato-magmatic volcano dates back to 2011.
Gallery
See also
List of volcanoes in Ethiopia
Dallol – a ghost town in the Dallol crater. It had the record high average temperature for an inhabited location on Earth.
References
Bibliography
On the Volcanoes of the World episode The Horn of Africa (2008; Science Channel)
External links
Photos from Dallol taken during an expedition to the Danakil in February 2008
YouTube
Wired
BBC
BBC
Afar Region
Astrobiology
Geologic formations of Ethiopia
Geochemistry
Hydrothermal vents
Iron minerals | Dallol (hydrothermal system) | [
"Chemistry",
"Astronomy",
"Biology"
] | 1,374 | [
"Origin of life",
"Speculative evolution",
"Astrobiology",
"nan",
"Biological hypotheses",
"Astronomical sub-disciplines"
] |
59,341,249 | https://en.wikipedia.org/wiki/Amanda%20Petford-Long | Amanda Karen Petford-Long is a Professor of Materials Science and Distinguished Fellow at the Argonne National Laboratory. She is also a Professor of Materials Science at Northwestern University.
Education and early career
Petford-Long studied physics at University College London, graduating in 1981. She earned a Doctor of Philosophy degree from the University of Oxford in 1985 for research on Beta-alumina solid electrolytes supervised by Colin Humphreys. She was a postgraduate student at St. Cross College, Oxford.
Career and research
Petford-Long served as professor at Corpus Christi College, Oxford, from 2002. She worked on spray coated nanocomposite materials and magnetic nanoparticles and used an atom probe. She was the only woman to be elected a Fellow of the Royal Academy of Engineering (FREng) in 2005. Petford-Long moved to Argonne National Laboratory in 2005.
She served as director of the Center for Nanoscale Materials from 2010 to 2014, developing new techniques for nanoscale characterisation. She delivered a lecture for the Chicago Council on Science and Technology in 2014.
She has explored the microstructure and magnetic field properties in multiferroic tunnel junctions. She works with Jacqueline Johnson on fluorozirconate glass for novel ceramics, using pulsed laser deposition to fabricate thin films. She has demonstrated that nanoparticle crystallisation impacts the optical properties of the glass ceramics. Pulsed laser deposition allows her to control the distribution of europium dopants and the nanocrystalline phase behaviour. The applications include up and down-converters for solar cells. She discussed their work on NPR in 2018.
Petford-Long develops in situ magnetised transmission electron microscopy (TEM) methods for examining magnetic thin film structures. She uses Lorentz transmission electron microscopy to identify the micromagnetic behaviour. She created skyrmions, chiral spin structures with no net charge. They used an ion-beam, allowing them to make skyrmion-like structures at a variety of length scales. She showed that non-repeating patterns in quasicrystals could be used to store information.
She serves as chair of the American Physical Society Division of Materials Physics from 2018 to 2019. She serves on the scientific advisory board of the Centre for Research on Adaptive Nanostructures and Nanodevices at Trinity College Dublin. She is Chair of the Argonne National Laboratory Chief Research Officer Council. She is an advocate for women in engineering and has been involved in initiatives to inspire young girls to choose engineering at college.
Awards and honors
Petford-Long is a Fellow of the American Physical Society, the Royal Microscopical Society and the Royal Academy of Engineering. She was elected a Distinguished Fellow at Argonne National Laboratory.
References
Year of birth missing (living people)
Living people
Female fellows of the Royal Academy of Engineering
Academics of the University of Oxford
Alumni of University College London
British materials scientists
Women materials scientists and engineers
British women physicists
British physicists
Alumni of St Cross College, Oxford
Fellows of the American Physical Society
20th-century English scientists
21st-century English scientists
20th-century English women scientists
21st-century English women scientists
English scientists | Amanda Petford-Long | [
"Materials_science",
"Technology"
] | 642 | [
"Women materials scientists and engineers",
"Materials scientists and engineers",
"Women in science and technology"
] |
59,342,907 | https://en.wikipedia.org/wiki/Agata%20Ciabattoni | Agata Ciabattoni is an Italian mathematical logician specializing in non-classical logic. She is a full professor at the Institute of Logic and Computation of the Faculty of Informatics at the Vienna University of Technology (TU Wien), and a co-chair of the Vienna Center for Logic and Algorithms of TU Wien (VCLA).
Education and career
Ciabattoni is originally from Ripatransone. She studied computer science at the University of Bologna, and completed her Ph.D. in 2000 at the University of Milan. Her dissertation, Proof-theory in many-valued logics, was supervised by Daniele Mundici.
She moved to Vienna in 2000 with the support of an EU Marie Curie Fellowship, and In 2007, she earned her habilitation at TU Wien.
She remains affiliated with TU Wien, as a professor in the faculty of informatics.
She also serves as the Collegium Logicum lecture series chair for the Kurt Gödel Society.
Contributions
One of Ciabattoni's projects at TU Wien involves using mathematical logic to formalize the ethical reasoning in the Vedas, a body of Indian sacred texts.
Recognition
In 2011, Ciabattoni won the Start-Preis of the Austrian Science Fund, the only woman to win the prize that year.
References
External links
Home page
Year of birth missing (living people)
Living people
Austrian mathematicians
Italian women mathematicians
Mathematical logicians
Women logicians
University of Bologna alumni
University of Milan alumni
Academic staff of TU Wien | Agata Ciabattoni | [
"Mathematics"
] | 306 | [
"Mathematical logic",
"Mathematical logicians"
] |
59,343,910 | https://en.wikipedia.org/wiki/New%20Zealand%20Hydrological%20Society | The New Zealand Hydrological Society (NZHS) is a non-profit organisation founded in 1961 to further the science of hydrology and its application to the understanding and management of New Zealand's water resources. The society is a constituent body of the Royal Society of New Zealand.
The society publishes the Journal of Hydrology (New Zealand) twice a year, since 1962.
References
External links
Hydrology organizations
Organizations established in 1961
1961 establishments in New Zealand
Professional associations based in New Zealand | New Zealand Hydrological Society | [
"Environmental_science"
] | 98 | [
"Hydrology",
"Hydrology organizations"
] |
59,354,087 | https://en.wikipedia.org/wiki/Trigonometric%20Rosen%E2%80%93Morse%20potential | The trigonometric Rosen–Morse potential, named after the physicists Nathan Rosen and Philip M. Morse, is among the exactly solvable quantum mechanical potentials.
Definition
In dimensionless units and modulo additive constants, it is defined as
where is a relative distance, is an angle rescaling parameter, and is so far a matching length parameter. Another parametrization of same potential is
which is the trigonometric version of a one-dimensional hyperbolic potential introduced in molecular physics by Nathan Rosen and Philip M. Morse and given by,
a parallelism that explains the potential's name. The most prominent application concerns the parametrization, with non-negative integer, and is due to Schrödinger who intended to formulate the hydrogen atom problem on Albert Einstein's closed universe, , the direct product of a time line with a three-dimensional closed space of positive constant curvature, the hypersphere , and introduced it on this geometry in his celebrated equation as the counterpart to the Coulomb potential, a mathematical problem briefly highlighted below.
The hypersphere is a surface in a four-dimensional Euclidean space, , and is defined as,
where , , , and are the Cartesian coordinates of a vector in , and is termed to as hyper-radius. Correspondingly, Laplace operator in is given by,
In now switching to polar coordinates,
one finds the Laplace operator expressed as
Here, stands for the squared angular momentum operator in four dimensions, while is the standard three-dimensional squared angular momentum operator. Considering now the hyper-spherical radius as a constant, one encounters the Laplace-Beltrami operator on as
With that the free wave equation on takes the form
The solutions, , to this equation are the so-called four-dimensional hyper-spherical harmonics defined as
where are the Gegenbauer polynomials. Changing in () variables as
one observes that the function satisfies the one-dimensional Schrödinger equation with the potential according to
The one-dimensional potential in the latter equation, in coinciding with the Rosen–Morse potential in () for and , clearly reveals that for integer values, the first term of this potential takes its origin from the centrifugal barrier on . Stated differently, the equation (), and its version () describe inertial (free) quantum motion of a rigid rotator in the four-dimensional Euclidean space, , such as the H Atom, the positronium, etc. whose "ends" trace the large "circles" (i.e. spheres) on .
Now the question arises whether the second term in () could also be related in some way to the geometry.
To the amount the cotangent function solves the Laplace–Beltrami equation on ,
it represents a fundamental solution on , a reason for which Schrödinger considered it as the counterpart to the Coulomb potential in flat space, by itself a fundamental solution to the Laplacian. Due to this analogy, the cotangent function is frequently termed to as "curved Coulomb" potential. Such an interpretation ascribes the cotangent potential to a single charge source, and here lies a severe problem. Namely, while open spaces, as is , support single charges, in closed spaces single charge can not be defined in a consistent way. Closed spaces are necessarily and inevitably charge neutral meaning that the minimal fundamental degrees of freedom allowed on them are charge dipoles (see Fig. 1).
For this reason, the wave equation
which transforms upon the variable change, , into the familiar one-dimensional Schrödinger equation with the trigonometric Rosen–Morse potential,
in reality describes quantum motion of a charge dipole perturbed by the field due to another charge dipole, and not the motion of a single charge within the field produced by another charge. Stated differently, the two equations () and () do not describe strictly speaking a Hydrogen Atom on , but rather quantum motion on of a light dipole perturbed by the dipole potential of another very heavy dipole, like the H Atom, so that the reduced mass, , would be of the order of the electron mass and could be neglected in comparison with the energy.
In order to understand this decisive issue, one needs to focus attention to the necessity of ensuring validity on of both the Gauss law and the superposition principle for the sake of being capable to formulate electrostatic there. With the cotangent function in () as a single-source potential, such can not be achieved. Rather, it is necessary to prove that the cotangent function represents a dipole potential. Such a proof has been delivered in. To understand the line of arguing of it is necessary to go back to the expression for the Laplace operator in () and before considering the hyper-radius as a constant, factorize this space into a time line and . For this purpose, a "time" variable is introduced via the logarithm of the radius. Introducing this variable change in () amounts to the following Laplacian,
The parameter is known as "conformal time", and the whole procedure is referred to as "radial quantization". Charge-static is now built up in setting =const in () and calculating the harmonic function to the remaining piece, the so-called conformal Laplacian, , on , which is read off from () as
where we have chosen , equivalently, .
Then the correct equation to be employed in the calculation of the fundamental solution is
.
This Green function to
has been calculated for example in.
Its values at the respective South and North poles, in turn denoted by , and , are reported as
and
From them one can now construct the dipole potential for a fundamental charge placed, say, on the North pole, and a fundamental charge of opposite sign, , placed on the antipodal South pole of . The associated potentials, and , are then constructed through multiplication of the respective Green function values by the relevant charges as
In now assuming validity of the superposition principle, one encounters a Charge Dipole (CD) potential to emerge at a point on according to
The electric field to this dipole is obtained in the standard way through differentiation as
and coincides with the precise expression prescribed by the Gauss theorem on , as explained in. Notice that stands for dimension-less charges. In terms of dimensional charges, , related to via
the potential perceived by another charge , is
For example, in the case of electrostatic, the fundamental charge is taken the electron charge, , in which case the special notation of
is introduced for the so-called fundamental coupling constant of electrodynamics. In effect, one finds
In Fig. 2 we display the dipole potential in ().
With that, the one-dimensional Schrödinger equation that describes on the quantum motion of an electric charge dipole perturbed by the trigonometric Rosen–Morse potential, produced by another electric charge dipole, takes the form of
Because of the relationship, , with being the node number of the wave function, one could change labeling of the wave functions, , to the more familiar in the literature, .
In eqs. ()-() one recognizes the one-dimensional wave equation with the trigonometric Rosen–Morse potential in () for and .
In this way, the cotangent term of the trigonometric Rosen–Morse potential could be derived from the Gauss law on in combination with the superposition principle, and could be interpreted as a dipole potential generated by a system consisting of two opposite fundamental charges. The centrifugal term of this potential has been generated by the kinetic energy operator on . In this manner, the complete trigonometric Rosen–Morse potential could be derived from first principles.
Back to Schrödinger's work, the hyper-radius for the H Atom has turned out to be very big indeed, and of the order of . This is by eight orders of magnitudes larger than the H Atom size. The result has been concluded from fitting magnetic dipole elements to hydrogen hyper-fine structure effects (see } and reference therein). The aforementioned radius is sufficiently large to allow approximating the hyper-sphere locally by plane space in which case the existence of single charge still could be justified. In cases in which the hyper spherical radius becomes comparable to the size of the system, the charge neutrality takes over. Such an example will be presented in section 6 below.
Before closing this section, it is in order to bring the exact solutions to the equations ()-(), given by
where stand for the Romanovski polynomials.
Application to Coulomb fluids
Coulomb fluids consist of dipolar particles and are modelled by means of direct numerical simulations. It is commonly used to choose cubic cells with periodic boundary conditions in conjunction with Ewald summation techniques. In a more efficient alternative method pursued by, one employs as a simulation cell the hyper spherical surface in (). As already mentioned above, the basic object on is the electric charge dipole, termed to as "bi-charge" in fluid dynamics, which can be visualized classically as a rigid "dumbbell" (rigid rotator) of two antipodal charges of opposite signs, and . The potential of a bi-charge is calculated by solving on the Poisson equation,
Here, is the angular coordinate of a charge placed at angular position , read off from the North pole, while stands for the anti-podal to angular coordinate of the position, at which the charge of opposite signs is placed in the Southern hemisphere. The solution found,
equals the potential in (), modulo conventions regarding the charge signs and units. It provides an alternative proof to that delivered by the equations ()-() of the fact that the cotangent function on has to be associated with the potential generated by a charge dipole. In contrast, the potentials in the above equations (), and (), have been interpreted in as due to so called single "pseudo-charge" sources, where a "pseudo-charge" is understood as the association of a point charge with a uniform neutralizing background of a total charge, .
The pseudo-charge potential, , solves .
Therefore, the bi-charge potential is the difference between the potentials of two antipodal pseudo-charges of opposite signs.
Application to color confinement and the physics of quarks
The confining nature of the cotangent potential in () finds an application in a phenomenon known from the physics of strong interaction which refers to the non-observability of free quarks, the constituents of the hadrons. Quarks are considered to possess three fundamental internal degree of freedom, conditionally termed to as "colors", red , blue , and green , while anti-quarks carry the corresponding anti-colors, anti-red , anti-blue , or anti-green , meaning that the non-observability of free quarks is equivalent to the non-observability of free color-charges, and thereby to the "color neutrality" of the hadrons. Quark "colors" are the fundamental degrees of freedom of the Quantum Chromodynamics (QCD), the gauge theory of strong interaction. In contrast to the Quantum Electrodynamics, the gauge theory of the electromagnetic interactions, QCD is a non-Abelian theory which roughly means that the "color" charges, denoted by , are not constants, but depend on the values, , of the transferred momentum, giving rise to the so-called, running of the strong coupling constant, , in which case the Gauss law becomes more involved. However, at low momentum transfer, near the so-called infrared regime, the momentum dependence of the color charge significantly weakens, and in starting approaching a constant value,
drives the Gauss law back to the standard form known from Abelian theories. For this reason, under the condition of color charge constancy, one can attempt to model the color neutrality of hadrons in parallel to the neutrality of Coulomb fluids, namely, by considering quantum color motions on closed surfaces. In particular for the case of the hyper-sphere , it has been shown in, that a potential, there denoted by , and obtained from the one in () through the replacement,
i.e. the potential
where is the number of colors, is the adequate one for the description of the spectra of the light mesons with masses up to . Especially, the hydrogen like degeneracies have been well captured. This because the potential, in being a harmonic function to the Laplacian on , has same symmetry as the Laplacian by itself, a symmetry that is defined by the isometry group of , i.e. by , the maximal compact group of the conformal group . For this reason, the potential in (), as part of , accounts not only for color confinement, but also for conformal symmetry in the infrared regime of QCD. Within such a picture, a meson is constituted by a quark -anti-quark color dipole in quantum motion on an geometry, and gets perturbed by the dipole potential in (), generated by and other color dipole, such as a gluon -anti-gluon , as visualized in Fig. 3.
The geometry could be viewed as the unique closed space-like geodesic of a four-dimensional hyperboloid of one sheet, , foliating outside of the causal Minkowski light-cone the space-like region, assumed to have one more spatial dimension, this in accord with the so-called de Sitter Special Relativity, . Indeed, potentials, in being instantaneous and not allowing for time orderings, represent virtual, i.e. acausal processes and as such can be generated in one-dimensional wave equations upon proper transformations of virtual quantum motions on surfaces located outside the causal region marked by the Light Cone. Such surfaces can be viewed as geodesics of the surfaces foliating the space like region. Quantum motions on open geodesics can give rise to barriers describing resonances transmitted through them. An illustrative example for the application of the color confining dipole potential in () to meson spectroscopy is given in Fig. 4. It should be pointed out that the potentials in the above equations () and () have been alternatively derived in, from Wilson loops with cusps, predicting their magnitude as , and in accord with ().
The potential in () has furthermore been used in in the Dirac equation on , and has been shown to predict realistic electromagnetic nucleon form-factors and related constants such as mean square electric-charge and magnetic-dipole radii, proton and nucleon magnetic dipole moments and their ratio, etc.
The property of the trigonometric Rosen-Morse potential, be it in the parametrization with in eq. (32)
which is of interest to electrodynamics, or in the parametrization of interest to QCD from the
previous section, qualifies it to studies of phase transitions in systems with electromagnetic or strong interactions on
hyperspherical "boxes" of finite volumes
. The virtue of such studies lies in the
possibility to express the temperature, , as the inverse, , to the radius of the hypersphere. For this purpose, knowledge on the partition function (statistical mechanics), here denoted by , of the potential under consideration is needed. In the following we evaluate for the case of the Schrödinger equation on
with linear energy (here in units of MeV),
where is the reduced mass of the two-body system under consideration. The
partition function (statistical mechanics) for this energy spectrum is defined in the standard way as,
Here, the thermodynamic beta is defined as with standing for the
Boltzmann constant. In evaluating it is useful to recall that with the increase of
the second term on the right hand side in () becomes negligible compared to the term proportional , a
behavior which becomes even more pronounced for the choices, , and . In both cases is
much smaller compared to the corresponding dimensionless factor, , multiplying . For this reason the partition function under investigation might be well approximated by,
Along same lines, the partition function for the parametrization corresponding to the Hydrogen atom on
has been calculated in, where a more sophisticated approximation has been employed. When transcribed to
the current notations and units, the partition function in presents itself as,
The infinite integral has first been treated by
means of partial integration giving,
Then the argument of the exponential under the sign of the integral has been cast as,
thus reaching the following intermediate result,
As a next step the differential has been represented as
an algebraic manipulation which allows to express the partition function in
() in terms of the function of complex argument according to,
where is an arbitrary path on the complex plane starting in zero and ending in
. For more details and physical interpretations, see.
See also
Romanovski polynomials
Pöschl–Teller potential
References
Quantum mechanical potentials
Mathematical physics | Trigonometric Rosen–Morse potential | [
"Physics",
"Mathematics"
] | 3,514 | [
"Applied mathematics",
"Theoretical physics",
"Quantum mechanics",
"Quantum mechanical potentials",
"Mathematical physics"
] |
59,355,695 | https://en.wikipedia.org/wiki/Manx%20comet | A Manx comet is a class of rocky minor celestial bodies that have a long-period comet orbit. Unlike most bodies on a long-period comet orbit which typically sport long, bright tails, a Manx comet is tailless, more typical of an inner Solar System asteroid. The nickname comes from the Manx breed of tailless cat. Examples include C/2013 P2 (PANSTARRS), discovered on 4 August 2013, which has an orbital period greater than 51 million years, and C/2014 S3 (PANSTARRS), discovered on 22 September 2014, which is thought to originate from the Oort cloud and could help explain the formation of the Solar System.
References
External links
JPL Small-Body Database Browser: C/2013 P2 (PANSTARRS)
JPL Small-Body Database Browser: C/2014 S3 (PANSTARRS)
Comets
Oort cloud | Manx comet | [
"Astronomy"
] | 183 | [
"Astronomical hypotheses",
"Oort cloud",
"Astronomy stubs",
"Comet stubs"
] |
47,423,949 | https://en.wikipedia.org/wiki/Suillus%20abietinus | Suillus abietinus is a species of edible mushroom in the genus Suillus. Found in Greece, it was described as new to science in 1970 by Maria Pantidou and Roy Watling from collections made in Vytina, Arkadia.
References
External links
abietinus
Fungi of Europe
Fungi described in 1970
Fungus species | Suillus abietinus | [
"Biology"
] | 69 | [
"Fungi",
"Fungus species"
] |
47,424,055 | https://en.wikipedia.org/wiki/Washington%20Savannah%20River%20Company | Washington Savannah River Company LLC was an environmental remediation company that operated the Savannah River Site, Aiken, South Carolina until 2009.
Overview
Washington Savannah River Company, LLC provides environmental cleanup, nuclear waste collection and disposal, and remediation services. The company was formerly known as Westinghouse Savannah River Company LLC, changing its name to Washington Savannah River Company, LLC in September 2005. The company was founded in 1989 and is based in Aiken, South Carolina. The new firm assumed the operation of the Savannah River Site from DuPont who had built and run the plant from 1950. Washington Savannah River Company, LLC operates as a subsidiary of Westinghouse Government Services Company LLC.
In 2008 the Department of Energy awarded the contract to manage and operate the Savannah River Site (SRS) to Savannah River Nuclear Solutions and a contract to manage the liquid waste at the Site to Savannah River Remediation. In 2009 Washington Savannah River Company, LLC's contract ended as the two new contractors took over operations.
References
Companies established in 1989
Privately held companies based in South Carolina
Construction and civil engineering companies of the United States
Nuclear technology companies of the United States
Energy engineering and contractor companies
Savannah River Site
1989 establishments in South Carolina | Washington Savannah River Company | [
"Engineering"
] | 244 | [
"Energy engineering and contractor companies",
"Engineering companies"
] |
47,425,238 | https://en.wikipedia.org/wiki/Bone%20growth%20factor | A bone growth factor is a growth factor that stimulates the growth of bone tissue.
Known bone growth factors include insulin-like growth factor-1 (IGF-1), insulin-like growth factor-2 (IGF-2), transforming growth factor beta (TGF-β), fibroblast growth factors (FGFs), platelet-derived growth factor (PDGF), parathyroid hormone-related peptide (PTHrP), bone morphogenetic proteins (BMPs), and certain members of the growth differentiation factor (GDF) group of proteins.
The ultimate target of bone growth factors are osteoblasts, osteoclasts and fibroblasts. Human fibroblasts and osteoblasts were shown to be capable of producing bone growth factors after stimulation.
Major hormones influencing bone growth and morphology include growth hormone (GH), androgens such as testosterone and dihydrotestosterone, and estrogens such as estradiol.
Types
Transforming growth factor beta
Transforming growth factor beta (TGF-β) is a physiological regulator of osteoblast differentiation, and acts as a central component in the coupling of bone formation and its resorption during bone remodeling.
Bone morphogenetic proteins
Bone morphogenetic proteins (BMPs) are proteins that are made of acidic polypeptides and belongs to the TGF-B family. BMPs promote the regeneration of bone tissue and cartilage. BMP exhibits osteoinductive activity. Osteoinductive activity leads to bone formation, activates mesenchymal cells to transform into osteoblasts which ultimately yield bone formation. BMP targets and binds to mesenchymal cells and activates a transmembrane serine/threonine kinase receptor which will lead to the phosphorylation of molecules called SMADS. SMADS are transcription factors that will induce osteoblast growth.
Platelet derived growth factor
The majority of the substrates of platelet-derived growth factor (PDGF) exhibit similar structures to Src Homology 2 domain. These substrates will bind to the PDGFR receptors which will dimerize and autophosphorylate. This phosphorylation attracted PLC-gamma (induces cell proliferation), Ras (which goes through signaling cascade and acts as a transcription factor), phosphatidylinositol 3-kinase (PI3K) which also promotes a signaling cascade inducing transcription factors, and stress fiber formation, and induces the STAT pathway which activates transcription factors.
Fibroblast growth factor
Platelet-derived growth factors (PDGFs) are polypeptides found in various tissues, including bone, where it was originally postulated that it could act as an autologous regulator of bone remodeling. This protein has been initially isolated in human platelets, and is composed of two different polypeptide chains A and B. The combination of these polypeptides form the homodimeric (AA) or (BB), or heterodimeric (AB) chains of PDGF. Fibroblast growth factor (FGF) signaling cascade is started by the binding of 2 growth factors to the FGFR. Dimerization takes place and initiates the transphosphorylation of each receptor. These phosphorylation sites act as docking sites for proteins so they may induce downstream signaling. These proteins consist of FRS2-alpha and PLC-gamma. FRS2-alpha acts as a scaffold protein to hold GAB1 and GRB2 which then proteins bind to SHP2 and SOS. These several proteins act together to activates the Ras pathway (induces cell proliferation and differentiation) and the PI3K pathway (induces survival and cell fate determination). On the other side of the dimerized receptors, PLC-gamma activates DAG and IP3 which yield PKC and calcium ions. PKC and calcium will ultimately induce morphology, migration, and adhesion.
Insulin-like growth factors
Insulin-like growth factors (IGF) assist bone growth in the body. IGF's are single-chain polypeptides that are similarly structured to insulin. There are 2 IGFs: Insulin-like growth factor 1 (IGF-1), and Insulin-like growth factor 2 (IGF-2). IGF-1 is induced by growth hormone (GH), and targets cartilage, stimulating cell bone cell proliferation. Studies carried out by Yakar S, Rosen CJ have shown in animal models that IGF-1 can enhance longitudinal growth, periosteal circumference, and bone mineral density. IGF-1 is responsible for increasing overall body size, longitudinal bone size, and height, especially during puberty.
Parathyroid hormone-related protein
Parathyroid hormone-related protein (PTHrP) is important for endochondral bone formation. Martin (2005) found that PTHrP stimulates bone formation by increasing osteoblast differentiation and reducing osteoblast apoptosis. This causes an increase in osteoblasts allowing for new bone cells to be formed. PTHrP also regulates osteoclast formation, further allowing for bone growth.
Hormones
Estrogens cause the hips to widen and become rounded during puberty in females, and androgens cause the shoulders to broaden in males. Estrogens mediate epiphyseal closure in both males and females. Other hormones implicated in control of bone growth include thyroid hormone, parathyroid hormone, calcitonin, glucocorticoids such as cortisol, and vitamin D (calcitriol). According to menoPAUSE, a blog from University of Rochester, estrogen causes females to have their fat distributed in their breasts, thighs, and along their pelvic area, implying that the fat can be used as an energy source for future pregnancies. For men, androgens (such as testosterone) increases male's muscle-to-fat ratio.
Clinical significance
Potential treatment for osteoporosis
Osteoporosis is a bone disease where bone mass is less than the average and can increase fractures. Some causes that lead to osteoporosis is how old you are, and decreasing amount of estrogen, which is why it mainly occurs in older women (however it can also impact men as well).
During a recent study performed at Children's Medical Center Research Institute at UT Southwestern, Bone Growth Factor Osteolectin (Clec11a) has also shown regenerative properties. Ovaries were removed from mice to simulate osteoporosis of post menopausal women. Results were based on daily injections of Osteolectin to determine the effects. This research showed an increase in bone volume of mice with bone loss after their ovaries were removed.
To be more specific, in order to help people with osteoporosis, medication is used along with treating bone fractures. Clec11a is a glycoprotein that bone marrow expresses which Elifesciences states.
Tendon treatment
Several studies have shown a correlation between the administration of bone growth factors and the amelioration of the tendon-to-bone healing. The focus of these studies was primarily on the anterior cruciate ligament (ACL) located in the knee, due to the high number of injuries sustained by athletes. The University of Dammam, King Fahd Hospital in Saudi Arabia was able to show that the addition of SHMSP bone growth factor via powder facilitated the process of tendon-graft healing in rabbits. Comparison of this SHMSP test group to the control group illustrated a higher level of formation and organization within the knee.
The Hospital for Special Surgery in New York conducted a similar study, in which a collagen sponge containing bone protein was implanted in the ACL of rabbits. In this case, the bone protein isolated from bovine femurs contained several bone morphogenetic proteins, which are part of an important signaling system that aides in the structure of bones. As with the application of SHMSP, the inclusion of bone protein in the collagen sponge was seen to improve the healing process, when compared to control groups with the sponge alone or no sponge.
In a separate study also implemented by the Hospital for Special Surgery as well as the University of California, treatment of the anterior cruciate ligament utilized the recombinant human bone morphogenic protein rhBMP-2 in two phases. In phase one, the dosages of noggin, a regulator protein, as well as rhBMP-2 were properly calibrated, and in phase two these proteins carried on synthetic calcium phosphate matrix (CPM) were then injected into the ACL region. The results of this procedure also demonstrated an improvement in the collagen fiber formation between the tendon and the bone.
Hence, all three treatments were seen to improve the efficacy of tendon-to-bone healing via the different bone growth factors: SHMSP, bone protein, and rhBMP-2.
References
Bones
Connective tissue
Growth factors | Bone growth factor | [
"Chemistry"
] | 1,924 | [
"Growth factors",
"Signal transduction"
] |
47,428,380 | https://en.wikipedia.org/wiki/Autospore | Autospores are a type of spores that are produced by algae to enable asexual reproduction and spread. They are non-motile and non-flagellated aplanospores that are generated within a parent cell and have the same shape as the parent cell before their release. Autospores are also known as resting spores. Algae primarily use three different types of spores for asexual reproduction - autospores, zoospores, and aplanospores. Autospores occur in several groups of algae, including Eustigmatophyceae, Dinoflagellates, and green algae. One example of a colonial alga that produces autospores is Dichotomococcus. This alga generates two autospores per reproducing cell, and the autospores escape through a slit in the cell wall and remain attached to the mother cell. Some study on autospores and algae in general include looking into its use for biofuel, animal feed, food supplements, nutraceuticals, and pharmaceuticals.
Autospore Formation
Autospores are the daughter cells formed by the internal division of a single cell. Autospores are formed during favorable conditions. Autospores are formed as a result of fission in the mitotic phase of cell division of green algae. Fission in the mitotic phase of cell division of green algae forms autospores. Cells may use different methods to produce different numbers of autospores or multinucleated autospores; for example, the Dictyochloropsis genus of algae can produce between 4 and 16 autospores when they reproduce. The cell can undergo a multipartition after two rounds of fission as happens in Kirchneriella lunaris. Pseudokirchneriella subcapitata follows a similar method of multiple fission after two nuclear divisions, which forms four autospores, but also has two other methods: binary fission, producing two autospores, or "two-autospore type," and multiple fission which produces eight autospores known as "eight-autospore type." Chlorella vulgaris produces between 2 and 32 autospores which burst out of the mother cell and use its debris as food in a process called autosporulation as studied and depicted by Ru in Chlorella vulgaris: a perspective on its potential for combining high biomass with high value bioproducts. The particular path a cell uses to produce autospores may vary not only by species, but also by environmental factors such as toxins or metals, such as Pseudokirchneriella subcapitata selecting between eight and two-autospore production based on concentration of potassium dichromate (K2Cr2O7) or 3,5-dichlorophenol (3,5-DCP) as studied by Yamagishi in Cell reproductive patterns in the green alga Pseudokirchneriella subcapitata (=Selenastrum capricornutum) and their variations under exposure to the typical toxicants potassium dichromate and 3,5-DCP. There are two stages of autospore formation. There is some synthesis during the process of cell growth, then, during the cell division stage, the synthesis is rapid. Once mature, the autospores will be released through the rupturing of the cell wall. After being released from the cell's autosporangium, the autospore will begin to synthesize a new daughter cells.
Behavior of Autospores
Autospores are aflagellate, and thus do not move on their own, instead being directed by currents. Autospores are self-germinating, and are named for this ability: "auto" being Greek for self, and "spora" for seed. Some autospores, produced through autosporulation, feed on the remains of the parent cell immediately after release. Autospores are small copies of the parent cell, in both shape and functioning, and thus behave the same once grown, including producing more autospores.
Other Algal Reproductive Methods
Algae can reproduce asexually, sexually, and vegetatively. Vegetative methods of algal reproduction include sinple cell division, fission, fragmentation, splitting of colonial forms, hormogonia, vegetative bodies, formation of adventitious branches, tubers, and budding. Sexual methods of algal reproduction include isogamy, anisogamy, oogamy, autogamy, and hologamy. Autospores are one of three primary kinds of spores which algae use to reproduce asexually, along with zoospores and aplanospores. Algae can also asexually reproduce through less commonly known hypnospores, akinetes, heterocysts, endospores, exospores, androspores, neutral spores, carpospores, tetraspores, and palmella stage. Zoospores are flagellate and can move to seek better conditions, whereas aplanospores and autospores are aflagellate and move only by environmental effects such as current. Aplanospores and zoospores are produced endogenously, or internally. Autospores are identical copies of the parent cell and cannot develop into zoospores. They are released through the rupturing of the parent cell wall.
References
Green algae
Dinoflagellate biology
Fungal morphology and anatomy
Germ cells | Autospore | [
"Biology"
] | 1,138 | [
"Algae",
"Green algae"
] |
47,428,621 | https://en.wikipedia.org/wiki/TI-54 | The TI-54 was a scientific calculator produced by Texas Instruments, primarily marketed towards engineers and science professionals. It was introduced in 1981, and at the time was the only calculator that could deal with complex numbers. It was discontinued in 1983.
The TI-54 touted features such as "built in algebraic functions for both real and complex numbers", "hyperbolic and trig functions for real numbers", and conversion functions such as polar to rectangular, and degrees/minutes/seconds to decimal degrees. It also came with Texas Instruments' Constant Memory feature, which allowed for data storage even after the calculator was turned off.
Unfortunately, this calculator, like some others of the "slanted series", had the so-called ti key disease, which means that pressed keys were either not recognized at all or were recognized as having been pressed several times.
Solving arithmetic problems became a game of patience and the correct result was only obtained through pure luck.
Texas Instruments later launched a recall campaign due to massive user complaints and exchanged this model for a successor with an improved keyboard free of charge.
References
External links
Datamath Calculator Museum
Texas Instruments calculators | TI-54 | [
"Technology"
] | 242 | [
"Computing stubs",
"Computer hardware stubs"
] |
47,429,141 | https://en.wikipedia.org/wiki/Strain%20rate%20imaging | Strain rate imaging is a method in echocardiography (medical ultrasound) for measuring regional or global deformation of the myocardium (heart muscle). The term "deformation" refers to the myocardium changing shape and dimensions during the cardiac cycle. If there is myocardial ischemia, or there has been a myocardial infarction, in part of the heart muscle, this part is weakened and shows reduced and altered systolic function. Also in regional asynchrony, as in bundle branch block, there is regional heterogeneity of systolic function. By strain rate imaging, the simultaneous function of different regions can be displayed and measured. The method was first based on colour tissue Doppler. by using the longitudinal myocardial velocity gradient, already in use transmurally. Later, the regional deformation has also been available by speckle tracking echocardiography, both methods having some, but different methodological weaknesses. Both methods, however, will acquire the same data (measurements may differ somewhat, however, being method dependent), and also can be displayed by the same type of display.
The point of deformation imaging, is that a passive segment in the myocardium for instance after an infarct, may move due to the action of an adjacent segment (tethering). Thus the displacement or velocity of a segment do not tell about the function of that segment. Deformation imaging, on the other hand, measures the differences of motion and velocity within the segment, which is equivalent to the deformation.
Basic concepts
Strain means Deformation, and is defined as relative change in length. The Lagrangian formula εL = (L-L0)/L0 = ΔL/L0, where L0 is baseline length and L is the resulting length, defines strain in relation to the original length as a dimensionless measure, where shortening will be negative, and lengthening will be positive. It is usually expressed in percent. An alternative definition, Eulerian strain defines the strain in relation to the instantaneous length: εE = ΔL/L. For a change over time, the Lagrangian strain will be: εL = Σ ΔL/L0, and Eulerian Strain εE = Σ (ΔL/L). The term was first used by Mirsky and Parmley in describing regional differences in deformation between normal and ischemic myocardium
Strain rate is the rate of deformation. In ultrasound it is usually measured from the velocity gradient SR = (v2 - v1)/L where v2and v1 are the myocardial velocities at two different points, and L is the instantaneous distance between them. This is thus equivalent to the velocity difference per length unit (the spatial derivative of velocity) and has the unit s−1. Strain is then integrated from strain rate. This method, however, yields the Eulerian strain rate and strain. It has become traditional to use the Velocity gradient, but in integrating strain rate it is converted to Lagrangian strain by the formula εL = eεE - 1.
Strain in three dimensions: Basically, any object or body is three dimensional, and can be deformed in different directions simultaneously. Strain can be described as a tensor with three principal strains (εx, εy and εz in a Cartesian coordinate system), and six shear strains components. In the heart, it has been customary to describe the three principal strain components as longitudinal (in the direction of the long axis of the ventricles), circumferential (in the direction of the ventricular circumference), and transmural (the deformation across the wall. Transmural deformation has also been called "radial", but this is unfortunate as in ultrasound in general the term radial describes "in the direction of the ultrasound beam"). However, as the heart muscle is incompressible, the three principal strain must balance; ((εx+1)(εy+1)(εz+1) = 1). As the ventricle contracts in systole, there is longitudinal shortening (negative strain), circumferential shortening (negative strain) and transmural (wall) thickening (positive strain). Due to this, and the fact that the left ventricle in normal conditions contract with a relatively invariant outer contour, the longitudinal strain contains the main information, while transmural strain (wall thickening) is a function of wall shortening, wall thickness and chamber diameter, while circumferential shortening is mainly a function of wall thickening. It has been shown clinically that longitudinal strain rate and wall thickening are diagnostically equivalent.
Methods
Strain rate imaging can be done by two principally different methods.
Tissue Doppler
The Tissue Doppler method is based on the colour Doppler, giving a velocity field with velocity vectors along the ultrasound beam over the whole sector. It measures the velocity gradient between two points along the ultrasound beam with a set distance. It gives the same result as the velocity gradient. This method has been validated experimentally in a mechanical model, in an animal model, and in patients against echocardiography, coronary angiography and MR
The method is limited to one direction; along the ultrasound beam, can thus mainly be used from the apical window, and for longitudinal strain and strain rate measurements only. It is sensitive to angle deviation between the velocity vector (direction of motion) and the ultrasound beam, and is sensitive to noise, especially clutter noise. It has a high temporal resolution, at the cost of a relatively low lateral spatial resolution.
Speckle tracking
Speckle tracking echocardiography is based on grey scale echocardiography (B-mode), and the fact that the reflected echo from the myocardium shows a speckle pattern that is a mixture of small scatters and interference patterns. The pattern being random, each region of the myocardium (called a "kernel"), has a unique speckle pattern, and that this speckle pattern is relatively stable, at least from one frame to next. By this, the movement of a kernel from one frame to the next, can be tracked by a "best match" search algorithm. The most commonly used is the "sum of absolute differences", shown to be similarly accurate as Cross-correlation. The method thus tracks a kernels motion from one frame to the next. From the frame rate, the velocity vector can be calculated, both in magnitude and direction. From this, a velocity field again can be generated over the whole sector, as with tissue Doppler, and strain rate can be derived, and then strain can be integrated. Alternatively strain can be measured directly from the change in distance between speckles. (resulting in Lagrangian strain directly), and strain rate derived temporally (it then has to be converted to Eulerian strain rate). The speckle tracking methods varies with non-commercial and commercial systems. Speckle tracking has been shown to be comparable to tissue Doppler derived strain, and has been validated against MR
The method tracks independently of the beam directions, and can thus track in two dimensions. It is also said to be independent of the angle error inherent in the Doppler algorithm. However, as the radial resolution (along the beam) is far better than the lateral resolution which also decreases with depth, both the angle independence and the tracking ability across the sector is lower. Also, instead of angle independency, the resulting strain values are dependent on the ROI (Region Of Interest) size and shape. Finally, in order to achieve tracking quality, the values are in most commercial applications smoothed by a spline smoothing function along the ROI, so the regional measurements are not pure regional, but rather to a degree, spline functions of the global average. In addition, the method has a lower sampling rate due to the limited frame rate of B-mode, which reduces tracking validity, especially at high heart rates.
Display
Both methods measures the same physiological phenomena (deformation), and results can in principle be displayed the same way.
Curves
The most common way is by displaying curves of the strain and strain rate, typically the time course during one heart cycle. Each curve will then represent the deformation in one region of the myocardium, but acquisition of a full sector allows display of multiple curves simultaneously in the same image for comparison.
Colour display
Strain and strain rate values can be reduced to colour coded images, where strain or strain rate are shown as colours in semi-quantitative parametric imaging. This makes the method more robust, but numerical values are not available. On the other hand, this may result in a better spatial resolution. The displays most commonly used, are Bull's eye (reconstructed from multiple apical planes), which displays all parts of the left ventricle simultaneously, but only at one point in time. This is useful for either mid systolic strain rate or end systolic strain. Inhomogeneous strain rate or strain, representing regions with reduced contractility are often very evident visually.
Curved anatomical M-mode from either one wall, or both walls simultaneously, gives a space-time diagram of the deformation, showing both spatial or temporal inhomogeneities in deformation. It is most useful when applied to strain rate, due to the rapid shifts in phase visible as seen by the figure. The strain rate values are reduced to semi quantitative visual display, but this mode allows measurement of timing, as well as depth, and is best suited to space-time relation measurement
Clinical use
It is a major point that strain rate imaging is just a part of an integrated echocardiographic examination. Like all other measures, deformation measurements have limited accuracy, and should be considered together with the rest of findings. Also, a knowledge of the pitfalls and artefacts of the specific methods, is an advantage. However, the methods offer unique ways of imaging regional dysfunction, that may strengthen the conclusion.
Regional function
Normal values for strain and strain rate has been established by the HUNT study.
Myocardial infarction
In myocardial infarction, a limited region of the heart muscle has reduced or totally absent function. It has been shown to be at least as accurate as B-mode echocardiography. Deformation imaging has also been shown to be useful in following recovery of an infarcted myocardial area, to ascertain the amount of Myocardial stunning vs. necrosis.
Myocardial ischemia
In stress echocardiography (see Cardiac stress test), the regional dysfunction due to ischemia will become evident when the myocardial oxygen demand surpasses the Coronary flow reserve of a stenosed coronary artery. Strain rate imaging during stress has been shown to give incremental value over ordinary echocardiography, both diagnostic and prognostic. In stress echo, the increased heart rate has speckle tracking at a disadvantage, due to the limited frame rate that affects tracking at higher heart rates.
Ventricular dyssynchrony
In Left bundle branch block (LBBB), the asynchronous activation of the left ventricle gives asynchronous contraction as well. This asynchrony can be visualised by ordinary echocardiography. It can also be demonstrated by tissue velocities, but strain rate imaging will in addition demonstrate the distribution of the asynchrony, and the demonstration of the amount of inefficient work done by the asynchronous ventricle. Disappointingly, large scale studies have not been able to establish additional echo criteria for selection of Heart failure patients with LBBB who may respond to Cardiac resynchronization therapy, although smaller studies are promising
Global function
In later years, Global strain by speckle tracking has achieved popularity as the global functional measure. It has an advantage over Ejection fraction (EF), it shows reduced cardiac function also in hypertrophic hearts with small ventricles and normal ejection fraction (HFNEF), which is often seen in Hypertensive heart disease, Hypertrophic cardiomyopathy and Aortic stenosis. The EF is not a pure functional measure, as it is also dependent on wall thickness It has also been shown to be more sensitive than EF. However, the incremental diagnostic and prognostic value of measuring LV shortening was already shown for the absolute measure
Global strain is basically LV shortening/LV end diastolic length, which means that this is a normalisation of LV shortening for LV heart size. It remains to be proven that this actually confers additional information.
References
Further reading
Sutherland; Hatle; Claus; D'hooge;Bijnens (2006) Doppler Myocardial Imaging. BSWK, Belgium.
Marwick; Yu; Sun (2007) Myocardial Imaging: Tissue Doppler and Speckle Tracking. Wiley-Blackwell.
Cardiac imaging
Medical equipment
Medical ultrasonography | Strain rate imaging | [
"Biology"
] | 2,695 | [
"Medical equipment",
"Medical technology"
] |
47,429,957 | https://en.wikipedia.org/wiki/Penicillium%20rolfsii | Penicillium rolfsii is a species of fungus in the genus Penicillium which produces patulin.
References
Further reading
rolfsii
Fungi described in 1930
Taxa named by Charles Thom
Fungus species | Penicillium rolfsii | [
"Biology"
] | 43 | [
"Fungi",
"Fungus species"
] |
47,432,780 | https://en.wikipedia.org/wiki/Kepler-182 | Kepler-182 is a star in the constellation of Cygnus. In the night sky, it is located at right ascension and declination . The star is notable for having two planets in the circumstellar habitable zone.
It has a radius of and an effective temperature of 6,250 K.
Two exoplanets orbit it. The first, Kepler-182b, has a radius of and orbits the parent star every 9.8 days. The second, Kepler-182c, has a radius of and orbits the parent star every 20.7 days.
References
Planetary systems with two confirmed planets
546
Cygnus (constellation) | Kepler-182 | [
"Astronomy"
] | 135 | [
"Cygnus (constellation)",
"Constellations"
] |
47,433,672 | https://en.wikipedia.org/wiki/Hubert%20Bray | Hubert Lewis Bray is a mathematician and differential geometer. He is known for having proved the Riemannian Penrose inequality. He works as professor of mathematics and physics at Duke University.
Early life and education
He earned his B.A. and B.S. degrees in Mathematics and Physics in 1992 from Rice University and obtained his Ph.D. in 1997 from Stanford University under the mentorship of Richard Melvin Schoen.
Career
He was an invited speaker at the 2002 International Congress of Mathematicians in Beijing (in the section of differential geometry).
He is one of the inaugural fellows of the American Mathematical Society.
Hubert was appointed professor of mathematics in 2004, an additionally professor of physics in 2019. In 2019, he was appointed director of undergraduate studies of Duke's mathematics department.
Personal life
Hubert is the grandson of Hubert Evelyn Bray, professor of mathematics at Rice University and the first person awarded a Ph.D. by the then Rice Institute.
Hubert Bray and his brother Clark Bray share similar educations and jobs, both having studied at Rice University (undergraduate), Stanford University (graduate), and are professors of mathematics at Duke University.
References
Year of birth missing (living people)
Living people
20th-century American mathematicians
Duke University faculty
Fellows of the American Mathematical Society
American theoretical physicists
Stanford University alumni
Rice University alumni
American mathematical physicists
American geometers
Mathematical analysts
21st-century American mathematicians | Hubert Bray | [
"Mathematics"
] | 281 | [
"Mathematical analysis",
"Mathematical analysts"
] |
47,434,539 | https://en.wikipedia.org/wiki/Boletus%20mamorensis | Boletus mamorensis is an edible fungus of the genus Boletus native to Morocco. It is closely related to B. aereus.
See also
List of Boletus species
References
External links
Edible fungi
Fungi described in 1978
mamorensis
Fungi of Africa
Fungus species | Boletus mamorensis | [
"Biology"
] | 57 | [
"Fungi",
"Fungus species"
] |
47,434,894 | https://en.wikipedia.org/wiki/Boletus%20violaceofuscus | Boletus violaceofuscus is a fungus of the genus Boletus native to China. First Described by W.F Chiu in 1948. It is related to Boletus separans.
Description
The cap has a diameter of 4-7 cm, hemispherical when young, broad to almost flat when mature. Colored dark blue, "Blue Violet," and sometimes ageing to "Maroon Purple," the top is usually smooth, rarely wrinkled or with corrugations with a faintly velvety texture. Pore tubes on the underside are 3-6mm long and 0.5 to 1mm wide, white when young a pale yellowish when mature or bruised.
The stipe is 5-7cm long and 1-2 cm thick, not strongly attached to the cap with a narrow top tending toward the thick middle shape typical of Boletus. The stipe is somewhat the same color as the cap, but paler with distinct white mesh veins. The flesh is solid, white and tending to become spongy when old, prone to infestation with larvae.
The spores appear green-gray or olive under the microscope, with a tapered elliptical shape of 12-14um x 5-6um size.
See also
List of Boletus species
References
External links
Edible fungi
Fungi described in 1948
violaceofuscus
Fungi of China
Fungus species | Boletus violaceofuscus | [
"Biology"
] | 282 | [
"Fungi",
"Fungus species"
] |
47,435,132 | https://en.wikipedia.org/wiki/16%20Lacertae | 16 Lacertae is a triple star system in the northern constellation of Lacerta, located about 1,580 light years from the Sun. It has the variable star designation EN Lacertae; 16 Lacertae is the Flamsteed designation. This system is visible to the naked eye as a faint blue-white hued star with a maximum apparent visual magnitude of +5.587. It is moving closer to the Earth with a heliocentric radial velocity of –12 km/s.
The binary nature of the brighter component was discovered in 1910 by astronomer Oliver J. Lee at Yerkes Observatory. The first orbital elements were published by Otto Struve and Nicholay T. Bobrovnikov in 1925. This is a single-lined spectroscopic binary with an orbital period of 12.1 days and a small eccentricity of 0.05. It forms an eclipsing binary variable, although only the eclipse of the primary component has been detected. This component is a Beta Cephei variable star with three dominant pulsation modes having frequencies of around six per day. It has a stellar classification of B2 IV, matching a B-type subgiant star with 9.5 times the mass of the Sun and 5.6 times the Sun's radius.
The unseen secondary is an F-type star of class F6–7. The tertiary component is a magnitude 11.4 star with a class of F0. As of 2008, it was located at an angular separation of from the primary.
References
B-type subgiants
Beta Cephei variables
Eclipsing binaries
Spectroscopic binaries
Triple star systems
Lacerta
Lacertae, 16
Durchmusterung objects
216916
113281
8725
Lacertae, EN | 16 Lacertae | [
"Astronomy"
] | 364 | [
"Lacerta",
"Constellations"
] |
68,631,023 | https://en.wikipedia.org/wiki/Crossotheca | Crossotheca is an extinct genus of seed ferns (Pteridospermatophyta) widespread in coal measures of Carboniferous, Permian and Triassic age, with possible Devonian remains known from Belgium. The type species is C. crepini, named and described in 1883 by R. Zeiller, and the genus is known from fossils found in Belgium (?), Canada, China, England, France, Hungary, Ireland, Poland and the United States.
One species, C. höninghausi, is the male fructification of Lyginodendron oldhami and the same species is the microsporangia-bearing member of Lyginopteris.
Description
A fertile Crossotheca branch shows the following features:
The branch tips are slightly expanded into a circular or paddle-shaped limb.
At the tip of each branch there are a few bilocular sporangia attached together.
Each sporangium contains a number of microspores (pollens).
References
Pteridospermatophyta
Carboniferous plants
Permian plants
Triassic plants
Prehistoric plants
Prehistoric plant genera
Fossil taxa described in 1883 | Crossotheca | [
"Biology"
] | 236 | [
"Prehistoric plants",
"Plants"
] |
68,632,213 | https://en.wikipedia.org/wiki/CAR-302%2C668 | CAR-302,668 (302668, α-isopropylmandelic acid (1-methyl-1,2,3,6-tetrahydro-4-pyridyl)methyl ester) is an anticholinergic deliriant drug, invented under contract to Edgewood Arsenal in the 1960s. It is a reasonably potent incapacitating agent with an ED50 of 4μg/kg and a long duration of action of around 16-24 hours.
See also
CAR-302,282
EA-3834
References
Deliriants
Muscarinic antagonists
Incapacitating agents
Carboxylate esters
Tertiary alcohols | CAR-302,668 | [
"Chemistry"
] | 139 | [
"Incapacitating agents",
"Chemical weapons"
] |
68,632,404 | https://en.wikipedia.org/wiki/Direct-drive%20sim%20racing%20wheel | A direct-drive simulator steering wheelbase (sometimes abbreviated "DD wheel") is a simulator steering wheel with a direct-drive mechanism between the drive and output, i.e. without gearing (as opposed to simulator steering wheels with reduction gearing via gears or belts), and is used similarly as with other simulator steering wheels for providing torque feedback (often called ""force" feedback", or FFB) so that the driver, through movement in the steering wheel, gets an interface for sensing what is happening to the car in the simulator. It is an example of human–computer interaction in driving simulators, racing simulators, and racing video games, and is an example of haptic technology
Direct-drive steering wheels typically differ from geared or belted sim racing wheels by being stronger (having more torque), and being able to more accurately reproduce details from the simulator. They are typically constructed using a 3-phase brushless AC servomotor (on more expensive models), or sometimes a hybrid stepper-servomotor, or only a stepper motor (on very affordable models).
In a direct drive simracing steering wheel system, the wheelbase and the wheel rim are typically separate, so that is possible to switch between rims according to the use case, for instance formula wheelrims, GT wheelrims, oval racing or truck wheel rims. The base and the rim are typically connected through a quick release system.
History
Direct-drive mechanisms for use in industrial arms began to be possible in the 1980s, with the use of rare-earth magnets, of which today the most commonly used are neodymium magnets.
Before the 1980s, servo motors were not powerful enough (did not have enough torque) to be used directly, and therefore reduction gears or mechanical belts were added to the motor to leverage and multiply its power. Higher-power motors were not feasible due to the expensive rare-earth materials needed to build them. This problem was surpassed in the 1980s, with the development of less-expensive high-power magnets.
In 2013, direct-drive sim steering wheels were introduced in large scale to the consumer mass market as a more advanced alternative to gear- and belt-driven steering wheels. The first commercially broadly available direct-drive wheel base was released in 2013 by the UK-based Leo Bodnar Electronics, after having been retailing to racing teams and professional centers since 2008. It was followed in 2015 by the US-based SimXperience AccuForce V1, and by the first do-it-yourself open-source hardware OpenSimwheel or "OSW" kits for users with good technical knowledge.
In 2015, a preliminary comparison of gear-driven and direct-drive wheels in the 0–30 Hz frequency range, for a study on hard real-time multibody simulation and high-fidelity steering wheel force feedback, concluded that direct-drive wheels are preferable.
Simucube was one of the manufacturers who previously provided Open Sim Wheel kits, and is a brand name owned by the Finnish manufacturer Granite Devices, which also supplies driver electronics for controlling servomotors and stepper motors, both for sim racing and industrial use. Granite Devices started as a hobby project by the Finn Kontkanen Tero when he was building a CNC milling machine, and realised that there was many alternating current servomotors of high quality on the market, but that driver electronics for controlling such motors was expensive or hard to come by. He investigated the operation of AC servos, and realized that it was possible to make usable control electronics with a handful of the latest electronic components and some real-time algorithms. The development of the controller then took around a year. The electronics are based on an IONI motherboard and STM32F4, and a proprietary firmware called MMos. An open source version of this software has been planned for release, but has not yet been released as of 2022.
Performance metrics
Issues, quality, and performance indicators of direct-drive wheels, and of sim racing wheels in general, include detail and fidelity of force feedback, smooth torque transmission, nearly-zero backlash, rotary encoder resolution, clipping, dynamic range, torque ripple, cogging torque, drivers and digital signal processing with control electronics, signal filtering, backdrive friction, low inertia, damping, fast response, precise positioning, electromagnetic interference, and latency.
Construction
Motors
The Leo Bodnar, OSW kits, Sim-pli.city and VRS systems are based on industrial servo motors (typically MiGE, Lenze, or Kollmorgen motors), while SimXperience's AccuForce, Frex, Simucube (which initially used a MiGE motor), Fanatec, and Simagic use custom-made motors. The types of motors used vary between high-end 3-phase brushless servomotors and lower budget hybrid stepper-servo motors. In-runner servo motors are typically smoother and more expensive than stepper or outrunner motors. Outrunner motors typically can produce more torque than inrunner motors, but need more cooling at higher torque levels.
Control electronics
Other than the motor, other parts of a complete direct-drive wheelbase include a rotary encoder (the position sensor), a controller board (that translate the FFB data from the game into steering wheel forces), and a motor driver board (servo drive), which fits into a slot of the controller board, and that controls the position, velocity and torque output of the motor. Examples of encoders are the Biss-C and the SinCos encoders, an example of a controller board is the Simucube board, and some examples of motor driver boards are the IONI and the Argon ones.
The motor encoder reads the position and/or motion (torque and rotation) of the shaft. The resolution of the encoder is typically measured in PPR (pulses per revolution), but sometimes CPR (counts, or steps, per revolution) is used instead, where 1 pulse equals 4 counts. The main advantage of very high resolution encoders is the ability to implement more advanced firmware or software FFB filters to the force feedback signal; for instance, encoders with a 21-bit resolution or more (2M steps or cpr), like the SinCos encoder, allow the servo-motor electronics to handle the filters more smoothly, and also allow to have more nuances in the FFB signal.
One of the main purposes of FFB filters is to optimize the FFB signal for a given wheelbase and rim device. The most basic FFB filters include the reconstruction filter, damper, friction and inertia. The reconstruction filter is included even in non-directdrive wheelbases, and has the effect of interpolating and smoothing the FFB signal from the game, to reduce the noise and artifacts from the FFB signal caused by the low update rate of a racing game. The wheel rim weight and size also have a significant effect on the perceived FFB signal, with lighter and smaller wheels being able to move faster and deliver more details.
More advanced FFB filters include static force reduction and slew rate reduction filter. The static force reduction filter was introduced to address a problem that emerged with high-torque DD wheelbase, due to their force output making too difficult to even turn the wheel with some cars in high-speed corners. The static force reduction filter introduced with Simucube 2 wheelbase allowed to address this issue while keeping a fully linear signal. A side-effect of this filter however is that while turning the wheel one feels a weakening of the FFB signal, which some drivers might dislike. Similarly, the slew rate reduction filter reduces or dampens sudden acceleration spikes in FFB torque, due for example to hitting kerbs or bumps. Therefore, the static force reduction and slew rate reduction filters make feasible to drive with higher maximum torque settings, which can enhance micro-details in the FFB signal.
Torque
The torque says something about how "powerful" the engine is, and can be specified in two ways:
Continuous torque, the greatest load of which the motor still can perform continuous movement at a continuous speed, and thus performing continuous work
Stall torque, the load which will cause the motor to stop so that it can no longer move, and thus produces a holding torque, but not performing any work
The latter always gives a higher number in newton-meters, and is therefore the number that usually is communicated the most by manufacturers to consumers, but is actually a less useful specification since the steering wheel in theory does not perform any work when rotation has stopped. One must therefore be aware of the type of torque specification given when comparing two motors. The relationship between the continuous torque and stall torque can vary between motors, and can say something about the motor characteristics (responsiveness versus strength).
For comparison, usually around 7-10 Nm is experienced in a street car, and on steering wheels with very high torque (e.g. 20 Nm) it may therefore be appropriate to adjust the torque down in the software. However, the stronger motors will often have a faster slew rate (the time an amplifier takes to respond to a signal) which gives better steering response and more realism.
Steering wheel mount
Similar to many real-world racing cars, sim-racing steering wheels usually come with a bolt circle of 6×70 mm, which means the wheel is mounted to the base via 6 evenly spaced out screws along a 70 mm circle on the steering wheel. Other bolt circles are sometimes used.
Some steering wheels attach to the base via quick release, as is commonly seen on many real-world racing cars, and these come in many varieties: Proprietary quick releases (e.g. Fanatec QR1 or Simucube SQR, the latter which has a wedge-shaped dovetail), or standardized quick releases such as the D1 spec (used by many manufacturers, including SimXperience, Simagic, Moza, IMMSource). D1 spec couplers are built to the same pattern as the NRG quick coupler approved for use in real-world racing cars per SFI Spec 42.1. Formerly, another common aftermarket quick release has been the Q1R type (not to be confused with the Fanatec QR1). Some quick releases have (often proprietary) integrated contact pins for transferring power and data to buttons and displays on the wheel, but these usually do not work across manufacturers. Others instead use wireless transmission via Bluetooth and inductive (magnetic) power transfer via the quick release. If using a steering wheel and base from two different manufacturers, it is usually possible to connect the steering wheel electronics to the base via a separate USB cable, for example connecting between USB-C, Micro, Mini, or Type B interfaces on the base and wheel.
Base mount
On bases with a high torque, the most robust mounting is usually achieved using an industry-standard front-mounted flange mount, and this is often preferred among sim racers, as such base mounts usually are less inclined to bend during heavy steering movements. This typically gives a shorter lever and therefore more sturdy mounting due to less torque on the mounting interface. A de facto industry standard among sim wheels, which again stems from a widely used mechanical industry standard, is a front mount with a bolt circle measuring 4×130 mm diameter and metric M8 screws, which means that four screws are evenly placed along a circle measuring 130 mm in diameter. This roughly corresponds to a square of 91.9 mm × 91.9 mm, which is often quoted as a square pattern with 92 mm long sides.
There are also a number of other proprietary patterns for mounting the base to a sim racing cockpit or table. Some of these instead have mounting on the sides or underside of the base.
List of direct-drive bases
Main specifications
Sorted chronologically by time of introduction:
Mount options and quick release
Legend:
See also
, for a comparison of other types of racing wheels
Full motion racing simulator
Linkage (mechanical)
Motion simulator
Power steering
Sawtooth wave
Servo drive
Servomechanism
Virtual reality headset
Notes
References
Further reading
Berber-Solano, T. P., Giacomin, J. A., & Ajovalasit, M. (2013) Effect of steering wheel acceleration frequency distribution on detection of road type, in Ingeniería mecánica, tecnología y desarrollo, 4(4), 145-151.
Walmsley, A., & Williams, L. R. T. (1991) The perception of torque pulses, in Perceptual and motor skills, 72(3_suppl), 1223-1227.
Yang, S., Tan, H. Z., Buttolo, P., & Johnston, M. (2004) Detection of torque vibrations transmitted through a passively-held rotary switch, in Proceedings of EuroHaptics 2004, 217-222.
External links
High end wheel comparison, by Gonzalo at boxthislap.org, December 11, 2017
SinCos impressions, by Gonzalo at boxthislap.org, December 7, 2017
Granite devices and OSW future, by Gonzalo at boxthislap.org, November 5, 2015
Sim Racing Garage Direct Drive FFB Wheel System Comparison, June 1, 2015
MMOS Direct drive wheel in 2020, at racedepartment.com, September 3, 2020
Driving simulators
Game controllers
Comparisons | Direct-drive sim racing wheel | [
"Technology"
] | 2,800 | [
"Driving simulators",
"Real-time simulation"
] |
68,632,682 | https://en.wikipedia.org/wiki/Time%20in%20the%20Comoros | Time in Comoros is given by a single time zone, officially denoted as East Africa Time (EAT; UTC+03:00). Comoros does not observe daylight saving time.
IANA time zone database
In the IANA time zone database, Comoros is given one zone in the file zone.tab – Indian/Comoro, which is an alias to Africa/Nairobi. "KM" refers to the country's ISO 3166-1 alpha-2 country code. Data for Comoros directly from zone.tab of the IANA time zone database; columns marked with * are the columns from zone.tab itself:
See also
Time in Africa
List of time zones by country
List of UTC time offsets
References
External links
Current time in Comoros at Time.is
Time in Comoros at TimeAndDate.com
Geography of the Comoros
Comoros
Comoros | Time in the Comoros | [
"Physics"
] | 177 | [
"Spacetime",
"Physical quantities",
"Time",
"Time by country"
] |
68,632,701 | https://en.wikipedia.org/wiki/Time%20in%20Tanzania | Time in Tanzania is given by a single time zone, officially denoted as East Africa Time (EAT; UTC+03:00). Tanzania does not observe daylight saving time.
IANA time zone database
In the IANA time zone database, Tanzania is given one zone in the file zone.tab – Africa/Dar es Salaam, which is an alias to Africa/Nairobi. "TZ" refers to the country's ISO 3166-1 alpha-2 country code. Data for Tanzania directly from zone.tab of the IANA time zone database; columns marked with * are the columns from zone.tab itself:
See also
Time in Africa
List of time zones by country
List of UTC time offsets
References
External links
Current time in Tanzania at Time.is
Time in Tanzania at TimeAndDate.com
Time by country
Geography of Tanzania
Time in Africa | Time in Tanzania | [
"Physics"
] | 175 | [
"Spacetime",
"Physical quantities",
"Time",
"Time by country"
] |
68,632,732 | https://en.wikipedia.org/wiki/Time%20in%20Uganda | Time in Uganda is given by a single time zone, officially denoted as East Africa Time (EAT; UTC+03:00). Uganda does not observe daylight saving time.
IANA time zone database
In the IANA time zone database, Uganda is given one zone in the file zone.tab – Africa/Kampala, which is an alias to Africa/Nairobi. "UG" refers to the country's ISO 3166-1 alpha-2 country code. Data for Uganda directly from zone.tab of the IANA time zone database; columns marked with * are the columns from zone.tab itself:
See also
Time in Africa
List of time zones by country
List of UTC time offsets
References
External links
Current time in Uganda at Time.is
Time in Uganda at TimeAndDate.com
Time by country
Geography of Uganda
Time in Africa | Time in Uganda | [
"Physics"
] | 172 | [
"Spacetime",
"Physical quantities",
"Time",
"Time by country"
] |
68,633,131 | https://en.wikipedia.org/wiki/Distillate%20%28motor%20fuel%29 | Distillate fuel, also called tractor fuel, was a petroleum product that was commonly used to power North American agricultural tractors from the early and mid-20th century. The product was crudely refined, akin to kerosene chemically, but impure.
Characteristics
North American distillate is broadly described as a fuel with heavier molecular weight than gasoline, and similar to or lighter than kerosene or No. 1 fuel oil. However, both usage of the term and formulation of the product varied widely. Octane ratings varied similarly, between 33 and 45.
Usage
Early railroad motor cars and tractors were offered with kerosene or gasoline-powered engines. Beginning in 1925, distillate-powered versions were offered, persisting until 1956, when the last "all-fuel" tractors were sold, while diesel-fueled tractors increased in popularity. Kerosene-engined tractors were phased out by 1934. Distillate fuel was used in machines with specific provisions for distillate, as well as all-fuel tractors which could handle kerosene, gasoline or distillate. Tractors designed for distillate could operate on gasoline, and were usually started with gasoline, but since they operated at a much lower compression ratio than gasoline-engined models, they developed less power on gasoline, and had to be warmed up with the more easily-volatilized gasoline before they could switch to distillate. Compression ratios for distillate could be about 4.7:1, while gasoline engines would run at 7:1 or more. Such machines were provided with small gasoline tanks for starting and warming up. However, distillate was often substantially less expensive than gasoline in farming regions, either because it was a less-refined product or because it was taxed at a lower rate or untaxed. "Power fuel" was a higher grade product that was somewhat short of gasoline in effectiveness.
Distillate fuel oil
Distillate was withdrawn from the market as cheaper and higher-grade gasoline and diesel fuels reached the markets. In time, "distillate" came to describe lighter fractions of diesel and fuel oil, with "No. 1 distillate" and "No. 2 distillate" referring to the lighter fractions of both products, albeit with different characteristics between fuel oil and diesel fuel.
See also
Tractor vaporising oil, a similar, but higher-quality product used from the late 1930s until 1974 in the United Kingdom and Australia
References
Petroleum products
Tractors
Fuels
Internal combustion piston engines | Distillate (motor fuel) | [
"Chemistry",
"Engineering"
] | 523 | [
"Tractors",
"Petroleum products",
"Chemical energy sources",
"Petroleum",
"Fuels",
"Engineering vehicles"
] |
68,637,122 | https://en.wikipedia.org/wiki/Book%20of%20the%20Zodiac | The Book of the Zodiac (; Modern Mandaic: Asfar Malwāši) is a Mandaean text. It covers Mandaean astrology in great detail. The book is used to obtain a Mandaean's baptismal name (malwasha). It is also an important source on Mandaean numerology.
Manuscripts and translations
An English translation of the text, based on Manuscript 31 of the Drower Collection (DC 31), was published by E. S. Drower in 1949. The manuscript is a kurasa, or unbound manuscript consisting of loose sheets.
Buckley has also located a privately held copy of the Book of the Zodiac dating from 1919, which belonged to Lamea Abbas Amara in San Diego.
There is also a manuscript of the Book of the Zodiac from 1789 CE that is currently held at the Bibliothèque National in Paris, which was used by Drower and may have also been used by Nicolas Siouffi.
Contents
Drower's manuscript (DC 31) consists of 289 pages in Mandaic. There are 20 individual books or sections, which are:
Book 1: The Book of the Signs of the Zodiac for Men
Book 2: The Book of the Signs of the Zodiac for Women
Book 3: The Book of Stars
Book 4: lists of astrological terms and calculations
Book 5: The Book of the Moon
Book 6: charms against evil spirits
Book 7: charms against evil spirits
Book 8: The Days of the Month
Book 9: illnesses
Book 10: astrological information
Book 11: selecting days for certain activities
Book 12: The Opening of a Door
Book 13: predictions
Book 14: predictions
Book 15: predictions
Book 16: predictions
Book 17: geographical regions governed by the planets and zodiac signs
Book 18: predictions
Book 19: transits of Saturn, halos of the sun, meteors and comets, and rainfall
Book 20: meteorology
There is also an appendix (labeled as Part II in Drower's text) that discusses omens, predictions, remedies, eclipses, and other topics.
See also
Ginza Rabba
Mandaean Book of John
References
External links
Code Sabéen 25 from Wikimedia Commons
Sfar Mulwasha (Mandaic text from the Mandaean Network)
Sfar Mulwasha (Mandaic text from the Mandaean Network)
Sfar Mulwasha (English translation)
Mandaean texts
Astrological texts
Numerology | Book of the Zodiac | [
"Mathematics"
] | 506 | [
"Numerology",
"Mathematical objects",
"Numbers"
] |
68,638,289 | https://en.wikipedia.org/wiki/Nikolay%20Korobov | Nikolai Mikhailovich Korobov (; November 23, 1917 – October 25, 2004) was a Soviet mathematician specializing in number theory and numerical analysis. He is best known for his work in analytic number theory, especially in exponential and trigonometric sums.
References
1917 births
2004 deaths
Soviet mathematicians
Russian mathematicians
Number theorists
Moscow State University alumni | Nikolay Korobov | [
"Mathematics"
] | 69 | [
"Number theory stubs",
"Number theorists",
"Number theory"
] |
68,638,522 | https://en.wikipedia.org/wiki/Buchholz%20hydra | In mathematics, especially mathematical logic, graph theory and number theory, the Buchholz hydra game is a type of hydra game, which is a single-player game based on the idea of chopping pieces off a mathematical tree. The hydra game can be used to generate a rapidly growing function, , which eventually dominates all recursive functions that are provably total in "", and the termination of all hydra games is not provably total in .
Rules
The game is played on a hydra, a finite, rooted connected tree , with the following properties:
The root of has a special label, usually denoted .
Any other node of has a label .
All nodes directly above the root of have a label .
If the player decides to remove the top node of , the hydra will then choose an arbitrary , where is a current turn number, and then transform itself into a new hydra as follows. Let represent the parent of , and let represent the part of the hydra which remains after has been removed. The definition of depends on the label of :
If the label of is 0 and is the root of , then = .
If the label of is 0 but is not the root of , copies of and all its children are made, and edges between them and 's parent are added. This new tree is .
If the label of is for some , let be the first node below that has a label . Define as the subtree obtained by starting with and replacing the label of with and with 0. is then obtained by taking and replacing with . In this case, the value of does not matter.
If the label of is , is obtained by replacing the label of with .
If is the rightmost head of , is written. A series of moves is called a strategy. A strategy is called a winning strategy if, after a finite amount of moves, the hydra reduces to its root. This always terminates, even though the hydra can get taller by massive amounts.
Hydra theorem
Buchholz's paper in 1987 showed that the canonical correspondence between a hydra and an infinitary well-founded tree (or the corresponding term in the notation system associated to Buchholz's function, which does not necessarily belong to the ordinal notation system ), preserves fundamental sequences of choosing the rightmost leaves and the operation on an infinitary well-founded tree or the operation on the corresponding term in .
The hydra theorem for Buchholz hydra, stating that there are no losing strategies for any hydra, is unprovable in .
BH(n)
Suppose a tree consists of just one branch with nodes, labelled . Call such a tree . It cannot be proven in that for all , there exists such that is a winning strategy. (The latter expression means taking the tree , then transforming it with , then , then , etc. up to .)
Define as the smallest such that as defined above is a winning strategy. By the hydra theorem, this function is well-defined, but its totality cannot be proven in . Hydras grow extremely fast, because the amount of turns required to kill is larger than Graham's number or even the amount of turns to kill a Kirby-Paris hydra; and has an entire Kirby-Paris hydra as its branch. To be precise, its rate of growth is believed to be comparable to with respect to the unspecified system of fundamental sequences without a proof. Here, denotes Buchholz's function, and is the Takeuti-Feferman-Buchholz ordinal which measures the strength of .
The first two values of the BH function are virtually degenerate: and . Similarly to the weak tree function, is very large, but less so.
The Buchholz hydra eventually surpasses TREE(n) and SCG(n), yet it is likely weaker than loader as well as numbers from finite promise games.
Analysis
It is possible to make a one-to-one correspondence between some hydras and ordinals. To convert a tree or subtree to an ordinal:
Inductively convert all the immediate children of the node to ordinals.
Add up those child ordinals. If there were no children, this will be 0.
If the label of the node is not +, apply , where is the label of the node, and is Buchholz's function.
The resulting ordinal expression is only useful if it is in normal form. Some examples are:
References
Further reading
External links
Trees (graph theory)
Mathematical games
Large numbers
Ordinal numbers
Theorems in discrete mathematics | Buchholz hydra | [
"Mathematics"
] | 931 | [
"Ordinal numbers",
"Mathematical theorems",
"Discrete mathematics",
"Mathematical games",
"Recreational mathematics",
"Mathematical objects",
"Theorems in discrete mathematics",
"Large numbers",
"Mathematical problems",
"Order theory",
"Numbers"
] |
68,639,524 | https://en.wikipedia.org/wiki/Toronto%20Declaration | The Toronto Declaration: Protecting the Rights to Equality and Non-Discrimination in Machine Learning Systems is a declaration that advocates responsible practices for machine learning practitioners and governing bodies. It is a joint statement issued by groups including Amnesty International and Access Now, with other notable signatories including Human Rights Watch and The Wikimedia Foundation. It was published at RightsCon on May 16, 2018.
The Declaration focuses on concerns of algorithmic bias and the potential for discrimination that arises from the use of machine learning and artificial intelligence in applications that may affect people's lives, "from policing, to welfare systems, to healthcare provision, to platforms for online discourse." A secondary concern of the document is the potential for violations of information privacy.
The goal of the Declaration is to outline "tangible and actionable standards for states and the private sector." The Declaration calls for tangible solutions, such as reparations for the victims of algorithmic discrimination.
Contents
The Toronto Declaration consists of 59 articles, broken into six sections, concerning international human rights law, duties of states, responsibilities of private sector actors, and the right to an effective remedy.
Preamble
The document begins by asking the question, "In a world of machine learning systems, who will bear accountability for harming human rights?" It argues that all practitioners, whether in the public or private sector, should be aware of the risks to human rights and approach their work with human rights in mind – conscious of the existing international laws, standards, and principles. The document defines human rights to include "the right to privacy and data protection, the right to freedom of expression and association, to participation in cultural life, equality before the law, and access to effective remedy"; but it states that the Declaration is most concerned with equality and non-discrimination.
Using the framework of international human rights law
The framework of international human rights law enumerates various rights, provides mechanisms to hold violators to account, and ensures remedy for the violated. The document cites the United Nations Human Rights Committee's definition of discrimination as "any distinction, exclusion, restriction or preference which is based on any ground [including but not limited to] race, colour, sex, language, religion, political or other opinion, national or social origin, property, birth or other status, and which has the purpose or effect of nullifying or impairing the recognition, enjoyment or exercise by all persons, on an equal footing, of all rights and freedoms."
Governments should proactively create binding measures, and private entities should create internal policies, to protect against discrimination. Measures may include protections for sensitive data, especially for vulnerable populations. Systems should be designed in collaboration with a diverse community in order to prevent discrimination in design.
Duties of states: human rights obligations
Governments today are deploying machine learning systems, often in collaboration with private entities. Even when development is contracted to such third parties, governments retain their obligation to protect human rights. Before implementation, and on an ongoing basis thereafter, they should identify risks and conduct regular audits, then take all necessary measures to mitigate these risks. They should be transparent about how machine learning is implemented and used, avoiding black box systems whose logic cannot be easily explained. Systems should be subject to strict oversight from diverse internal committees and independent judicial authorities.
Governments must also protect citizens from discrimination by private entities. In addition to oversight, they should pass binding laws against discrimination, as well as for data protection and privacy, and they should provide effective means to remedy for affected individuals. It is important for national and regional governments to expand on and contextualize international law.
Responsibilities of private sector actors: human rights due diligence
Private entities are responsible for conducting "human rights due diligence." Just like governments, private entities should identify risks before development by considering common risks and consulting stakeholders, "including affected groups, organizations that work on human rights, equality and discrimination, as well as independent human rights and machine learning experts." They should design systems that mitigate risks, subject systems to regular audits, and forego projects that carry too high of risks. They should be transparent about assumed risks, including details of the technical implementation where necessary, and should provide a mechanism for affected individuals to dispute any decisions that affect them.
The right to an effective remedy
"The right to justice is a vital element of international human rights law." Private entities should create processes for affected individuals to seek remedy, and they should designate roles for who will oversee these processes. Governments must be especially cautious when deploying machine learning systems in the justice sector. Transparency, accountability, and remedy can help.
References
Machine learning
Information ethics
2018 documents
Computing and society
Manifestos
Regulation of artificial intelligence | Toronto Declaration | [
"Technology",
"Engineering"
] | 950 | [
"Regulation of artificial intelligence",
"Machine learning",
"Computing and society",
"Ethics of science and technology",
"Artificial intelligence engineering",
"Information ethics"
] |
68,639,743 | https://en.wikipedia.org/wiki/List%20of%20investigational%20obsessive%E2%80%93compulsive%20disorder%20drugs | This is a list of investigational obsessive–compulsive disorder drugs, or drugs that are currently under development for clinical use in the treatment of obsessive–compulsive disorder (OCD) but are not yet approved.
Chemical/generic names are listed first, with developmental code names, synonyms, and brand names in parentheses.
This list was last comprehensively updated in September 2021. It is likely to become outdated with time.
Under development
Actively under development
Immunoglobulin (immune globulin 10%, 10% high purity immunoglobulin, 10% IVIG, NewGam, Newnorm, Octagam 10%, Octagam, Panzyga) – immunoglobulin / immunostimulant
Troriluzole (BHV-4157, BHV-4157a, FC-4157; trigriluzole) – prodrug of riluzole / glutamate modulator
Preclinical development
Cannabis extracts (various) – cannabinoid receptor modulators
No development reported
4'-Fluorocannabidiol (4'-F-CBD; fluorinated cannabidiol; HUF-101, HUF-102, HUF-103) – cannabinoid receptor modulator, other actions
AbbVie/Rugen research programme – unspecified mechanism of action
Agomelatine (Alodil, Melitor, Thymanax, Valdoxan, Vestin; AGO-178, AGO178C, S-20098, S-20098-F55) – serotonin 5-HT2C receptor antagonist and melatonin receptor agonist
CR-5542 – orexin receptor antagonist
Dual SSRIs and serotonin 5-HT1A receptor agonists (SSA-426, WAY-163426, WAY-211612, WAY-253752, WAY-426)
Risperidone (Risperdal, Risperdal Consta, Risperdal Depot; JNJ-410397-AAA, R-64766, R064766) – atypical antipsychotic / monoamine receptor modulator
Secretin (SecreFlo; INN-329, RG-1068) – hormone/diagnostic agent
Sosei Heptares research programme – various mechanisms of action
Not under development
Development discontinued
Bitopertin (R-1678, RG-6718, RG1678, RO-4917838) – glycine GlyT1 inhibitors / glycine reuptake inhibitor
Cycloserine (D-cycloserine; TIK-101) – glutamate NMDA receptor partial agonist
Elzasonan (CP-448187, CP-448187-01) – serotonin 5-HT1B and 5-HT1D receptor antagonist
F-14258 – serotonin 5-HT1B and 5-HT1D receptor antagonist
Fluoxetine/naltrexone (OREX-004) – selective serotonin reuptake inhibitor and opioid receptor antagonist
Mavoglurant (AFQ-056) – glutamate mGlu5 receptor antagonist
NPL-2003 – glutamate modulator
Ondansetron (Setrodon; TO-2061) – serotonin 5-HT3 receptor antagonist
RO-600175 – serotonin 5-HT2C receptor agonist
Roxindole (EMD-49980) – dopamine receptor agonist, serotonin receptor modulator, adrenergic receptor modulator, and serotonin reuptake inhibitor
SB-200646 (SB-200646A) – serotonin 5-HT2B and 5-HT2C receptor antagonist
Formal development never or not yet started
5-HT6 receptor agonists (e.g., WAY-181187, WAY-208466)
Antiandrogens (e.g., flutamide, cyproterone acetate, triptorelin)
Cannabinoids (e.g., nabilone, tetrahydrocannabinol (THC)/cannabis) – cannabinoid receptor modulators
NMDA receptor modulators (e.g., ketamine, memantine, nitrous oxide, rapastinel)
Nonsteroidal anti-inflammatory drugs (NSAIDs) (e.g., celecoxib, naproxen) – cyclooxygenase inhibitors
Rituximab (Rituxan) – monoclonal antibody against CD20
Serotonergic psychedelics (e.g., psilocybin/psilocybin mushrooms, lysergic acid diethylamide (LSD)) – serotonin receptor modulators
Tolcapone (Tasmar) – catechol-O-methyltransferase inhibitor
Clinically used drugs
Approved drugs
Clomipramine (Anafranil) – tricyclic antidepressant / monoamine reuptake inhibitor and receptor modulator
Escitalopram (S-citalopram; Cipralex, Entact, Lexapro, Seroplex, Sipralex, Sipralexa; LU-26054; MLD-55) – selective serotonin reuptake inhibitor
Fluoxetine (Prozac, Prozac Weekly, Reneuron, Sarafem; LY-110140) – selective serotonin reuptake inhibitor
Fluvoxamine (Depromel, Luvox, Luvox CR; SME-3110) – selective serotonin reuptake inhibitor and sigma-1 receptor agonist
Paroxetine (Aropax, Deroxat, Divarius, Dropax, Dropaxin, Frosinor, Motivan, Paxil, Paxil CR, Serestill, Seroxat, Tagonis; BRL-29060, BRL-29060A, FG-7051, NNC-207051, SI-211103) – selective serotonin reuptake inhibitor
Sertraline (Aremis, Besitran, Gladem, J Zoloft, Lustral, Serad, Serlain, Tatig, Zoloft; CP-51974, CP-51974-01) – selective serotonin reuptake inhibitor
Off-label drugs
Atypical antipsychotics (e.g., aripiprazole, olanzapine, quetiapine, risperidone) – monoamine receptor modulators
See also
List of investigational drugs
References
Further reading
External links
AdisInsight - Springer
Obsessive-compulsive disorder drugs, investigational
Dynamic lists
Experimental psychiatric drugs | List of investigational obsessive–compulsive disorder drugs | [
"Chemistry"
] | 1,485 | [
"Drug-related lists"
] |
55,955,952 | https://en.wikipedia.org/wiki/NGC%20966 | NGC 966 is an unbarred lenticular galaxy approximately 440 million light-years away from Earth in the constellation of Cetus. It was discovered by American astronomer Francis Preserved Leavenworth in 1886.
See also
Lenticular galaxy
List of NGC objects (1–1000)
Cetus (constellation)
References
External links
SEDS
Unbarred lenticular galaxies
Cetus
966
9626
Astronomical objects discovered in 1886
Discoveries by Francis Leavenworth | NGC 966 | [
"Astronomy"
] | 90 | [
"Cetus",
"Constellations"
] |
55,956,520 | https://en.wikipedia.org/wiki/Quantum%20crystallography | Quantum crystallography is a branch of crystallography that investigates crystalline materials within the framework of quantum mechanics, with analysis and representation, in position or in momentum space, of quantities like wave function, electron charge and spin density, density matrices and all properties related to them (like electric potential, electric or magnetic moments, energy densities, electron localization function, one electron potential, etc.).
Like the quantum chemistry, Quantum crystallography involves both experimental and computational work. The theoretical part of quantum crystallography is based on quantum mechanical calculations of atomic/molecular/crystal wave functions, density matrices or density models, used to simulate the electronic structure of a crystalline material. While in quantum chemistry, the experimental works mainly rely on spectroscopy, in quantum crystallography the scattering techniques (X-rays, neutrons, γ-Rays, electrons) play the central role, although spectroscopy as well as atomic microscopy are also sources of information.
The connection between crystallography and quantum chemistry has always been very tight, after X-ray diffraction techniques became available in crystallography. In fact, the scattering of radiation enables mapping the one-electron distribution or the elements of a density matrix.
The kind of radiation and scattering determines the quantity which is represented (electron charge or spin) and the space in which it is represented (position or momentum space).
Although the wave function is typically assumed not to be directly measurable, recent advances enable also to compute wave functions that are restrained to some experimentally measurable observable (like the scattering of a radiation).
The term Quantum Crystallography was first introduced in revisitation articles by L. Huang, L. Massa and Nobel Prize winner Jerome Karle, who associated it with two mainstreams: a) crystallographic information that enhances quantum mechanical calculations and b) quantum mechanical approaches to improve crystallography information. This definition mainly refers to studies started in the 1960s and 1970s, when first attempts to obtain wave functions from scattering experiments appeared, together with other methods to constrain a wavefunction to experimental observations like the dipole moment. This field has been recently reviewed, within the context of this definition.
Parallel to studies on wave function determination, R. F. Stewart and P. Coppens investigated the possibilities to compute models for one-electron charge density from X-ray scattering (for example by means of pseudoatoms multipolar expansion), and later of spin density from polarized neutron diffraction, that originated the scientific community of charge, spin and momentum density.
In a recent review article, V. Tsirelson gave a more general definition: "Quantum crystallography is a research area exploiting the fact that parameters of quantum-mechanically valid electronic model of a crystal can be derived from the accurately measured set of X-ray coherent diffraction structure factors".
The book Modern Charge Density Analysis offers a survey of the research involving Quantum Crystallography and of the most adopted experimental or theoretical methodologies.
The International Union of Crystallography has recently established a commission on Quantum Crystallography, as extension of the previous commission on Charge, Spin and Momentum density, with the purpose of coordinating research activities in this field.
External links
The Erice School of crystallography (52nd course): first course on Quantum crystallography (June 2018)
The XIX Sagamore Conference (July 2018)
The CECAM meeting on Quantum crystallography (June 2017)
The IUCr commission on Quantum crystallography
The International Union of Crystallography
References
Crystallography
Quantum mechanics | Quantum crystallography | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 726 | [
"Theoretical physics",
"Materials science",
"Quantum mechanics",
"Crystallography",
"Condensed matter physics"
] |
55,956,711 | https://en.wikipedia.org/wiki/NGC%206810 | NGC 6810 is a spiral galaxy approximately 87 million light-years away from Earth in the constellation of Pavo.
Observational history
NGC 6810 was discovered by John Herschel on July 10, 1834. It was later added to the New General Catalogue by John Louis Emil Dreyer.
Misclassification of NGC 6810
This galaxy used to be classified as a Seyfert 2 galaxy, but that is probably incorrect. Recent X-ray observations provide no evidence of any active galactic nucleus (AGN) activity, and high resolution optical spectra do not confirm the status of NGC 6810 as a Seyfert galaxy, thus it appears to have been misclassified.
Features
NGC 6810 is an early-type spiral of roughly equivalent mass to the Milky Way. X-ray, optical, IR and radio properties of NGC 6810 are all consistent with a starburst galaxy.
Galactic-scale superwind
Observation of NGC 6810 with XMM-Newton reveals the presence of extended soft X-ray emission within the optical disc of the galaxy (which is closely associated with star-forming regions) and also beyond the optical disc. This, along with Hα filamentation and peculiar minor axis ionized gas kinematics, strongly suggest that NGC 6810 is host to a galactic-scale superwind which is streaming from the starburst region.
The actively star-forming regions and the base radius of the outflow are unusually spread out, and extend out to a radius of ~6.5 kpc from the nucleus. Most superwinds in other galaxies appear to arise in ≲ 1 kpc-scale nuclear starburst regions. That makes NGC 6810 one of the few ‘disc-wide’ superwinds currently known, because NGC 6810's superwind base extends across nearly 70 percent of the entire galaxy's diameter. Only three other starburst galaxies are known to have broad superwind sources.
See also
List of NGC objects (6001–7000)
References
External links
SEDS
Unbarred spiral galaxies
Starburst galaxies
Pavo (constellation)
6810
63571
Astronomical objects discovered in 1834
Discoveries by John Herschel | NGC 6810 | [
"Astronomy"
] | 440 | [
"Constellations",
"Pavo (constellation)"
] |
55,957,212 | https://en.wikipedia.org/wiki/Caldanaerobacter | Caldanaerobacter is a Gram-positive or negative and strictly anaerobic genus of bacteria from the family of Thermoanaerobacteraceae.
Phylogeny
The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI)
See also
List of bacterial orders
List of bacteria genera
References
Further reading
Thermoanaerobacterales
Bacteria genera
Anaerobes | Caldanaerobacter | [
"Biology"
] | 99 | [
"Bacteria",
"Anaerobes"
] |
55,957,258 | https://en.wikipedia.org/wiki/Caldanaerobacter%20uzonensis | Caldanaerobacter uzonensis is a thermophilic, anaerobic and heterotrophic bacterium from the genus of Caldanaerobacter which has been isolated from a hot spring in Uzon Caldera in Russia.
References
Thermoanaerobacterales
Bacteria described in 2010
Thermophiles
Anaerobes | Caldanaerobacter uzonensis | [
"Biology"
] | 73 | [
"Bacteria",
"Anaerobes"
] |
55,957,399 | https://en.wikipedia.org/wiki/Kalle%20Lyytinen | Kalle Lyytinen (born August 19, 1953 in Helsinki) is the Iris S. Wolstein Professor of Management Design at Case Western Reserve University's Weatherhead School of Management, where he is also director of their Doctor of Management program. His research focuses on how organizations design and manage digital innovations. Lyytinen is notable for his breadth of scholarship and leadership in the field of Information Systems. In 2013, he received the Association for Information Systems Leo Award, which is the association's top honor.
Background
Lyytinen is notable for his breadth of scholarship and leadership in the field of Information Systems. In 2013 he received the Association for Information Systems Leo Award, which is the association's top honor. A study published in 2016 found that Lyytinen was the field's most central researcher - essentially the Paul Erdos of Information Systems. He is the former Editor-in-Chief of the Journal of the Association for Information Systems.
Lyytinen has written over 300 scholarly publications. Notable books include: Information Systems : The State of the Field, with John Leslie King, published by John Wiley & Sons in 2006, and, Information Systems Development and Data Modeling - Conceptual and Philosophical Foundations, with Rudy Hirschheim and Heinz Klein, published by Cambridge University Press in 1995/2008.
Lyytinen received his PhD, Econ Lic, and MS from the University of Jyvaskyla (Finland), and has received honorary doctorates from Umeå University (Sweden), Copenhagen Business School (Denmark), and Lappeenranta University of Technology (Finland).
References
1953 births
Living people
Case Western Reserve University faculty
Information systems researchers | Kalle Lyytinen | [
"Technology"
] | 342 | [
"Information systems",
"Information systems researchers"
] |
55,957,695 | https://en.wikipedia.org/wiki/NGC%201984 | NGC 1984 (also known as ESO 56-SC132) is an open cluster associated with an emission nebula, it is located in the constellation Dorado in the Large Magellanic Cloud. It was discovered by John Herschel on 16 December 1835. The apparent magnitude is 9.9 and its size is 1.50 by 1.20 arc minutes.
NGC 1984 contains a star called NGC 1984-16 which is at these co-ordinates 05 27 41.0 -69 08 06.
See also
Open Cluster
List of NGC objects (1001–2000)
Dorado (constellation)
References
External links
SEDS
Emission nebulae
Open clusters
ESO 56-SC132
1984
Dorado
Astronomical objects discovered in 1835
Discoveries by John Herschel
Large Magellanic Cloud | NGC 1984 | [
"Astronomy"
] | 158 | [
"Dorado",
"Constellations"
] |
55,957,766 | https://en.wikipedia.org/wiki/Transplatin | trans-Dichlorodiammineplatinum(II) is the trans isomer of the coordination complex with the formula trans-PtCl2(NH3)2, sometimes called transplatin. It is a yellow solid with low solubility in water but good solubility in DMF. The existence of two isomers of PtCl2(NH3)2 led Alfred Werner to propose square planar molecular geometry. It belongs to the molecular symmetry point group D2h.
Preparation and reactions
The complex is prepared by treating [Pt(NH3)4]Cl2 with hydrochloric acid.
Many of the reactions of this complex can be explained by the trans effect. It slowly hydrolyzes in aqueous solution to give the mixed aquo complex trans-[PtCl(H2O)(NH3)2]Cl. Similarly it reacts with thiourea (tu) to give colorless trans-[Pt(tu)2(NH3)2]Cl2. In contrast, the cis isomer gives [Pt(tu)4]Cl2. Oxidative addition of chlorine gives trans-PtCl4(NH3)2.
Medicinal chemistry
trans-Dichlorodiammineplatinum(II) has had far less impact on medicinal chemistry compared to its cis isomer, cisplatin, which is a major anticancer drug. Nonetheless, replacement of the ammonia with other ligands has led to highly active drugs that have attracted much attention.
References
Ammine complexes
Coordination complexes
Platinum(II) compounds
Chloro complexes
Platinum complexes | Transplatin | [
"Chemistry"
] | 335 | [
"Coordination chemistry",
"Coordination complexes"
] |
55,958,085 | https://en.wikipedia.org/wiki/TSD%20Desalination | TSD Desalination (Tethys Solar Desalination) is an Israeli startup company that provides solar-powered desalination technology. Jewish Business News named TSD one of 25 cool Israeli startups to watch in 2017, and CNBC mentioned TSD alongside IDE Technologies in a review of Israeli high-tech.
TSD was founded in 2014. Their technology, developed by Joshua Altman and Prof. Moshe Tshuva at Afeka College of Engineering in Tel Aviv, uses solar energy directly to power desalination and water treatment. Ze'ev Emmerich, a founder of TSD, claims their method is scalable and environmentally friendly, as well as being cheaper than reverse osmosis.
References
External links
Tethys Solar Desalination
Technology companies of Israel
Water desalination
Israeli companies established in 2014 | TSD Desalination | [
"Chemistry"
] | 170 | [
"Water treatment",
"Water technology",
"Water desalination"
] |
55,958,393 | https://en.wikipedia.org/wiki/Cosmoball | Cosmoball, also known as Goalkeeper of the Galaxy () is a 2020 Russian 3D superhero space opera film written and directed by Dzhanik Fayziev, based on the animated series Galactik Football, with the participation of the television channel Russia-1. The film is set in the future, a post-apocalyptic city in a world inhabited by survivors of an intergalactic war that has shifted the planet's poles. Above the city towers a huge alien ship - it is a stadium, the planet's fate rests in the hands of the willing and capable Cosmoball players who are defending the Earth. The fate of the planet depends on the result of the match between earthlings and aliens.
Andrey Rubanov also participated in the writing of the script, and among the producers are Sergey Selyanov and Innokentiy Malinkin. It stars Yevgeny Romantsov as Anton a goalkeeper to the national team, alongside Viktoriya Agalakova, Maria Lisovaya, Ivan Ivanovich, Liza Taychenacheva, Yevgeny Mironov, and Elena Yakovleva in supporting roles.
Location filming began on June 2, 2017 and principal photography locations included the Mosfilm Studios. Shooting took place at Mosfilmovskaya Street in Moscow, and lasted until mid-September 2017.
The film required a wide use of computer-generated imagery to portray the rare alien races and space monsters.
Cosmoball was scheduled to be theatrically released in Russia on August 27, 2020, in 2D, RealD 3D formats, with distribution in Russia handled by "Nashe Kino" (English: "Our Cinema").
The film was the first major Russian project to be released after the limitation of the number of viewers in cinemas due to the outbreak of the coronavirus. The film grossed 106 million rubles with a budget of 786 million rubles, becoming a box-office failure.
Plot
In a post-apocalyptic era, the Earth has been ravaged by a series of galactic wars, leading to the destruction of the Moon and the shifting of the Earth's poles, drastically changing the planet's climate. Moscow now lies in a tropical forest zone, while New York is covered in ice. The city is a hub of diversity, resembling an anti-utopian cyberpunk version of Brazil, where representatives of different races and subcultures, strange individuals, exotic animals, and engineering marvels coexist on sun-drenched streets.
Hovering over Moscow is an enormous alien spaceship, which serves as a stadium for the intergalactic sport of Cosmoball, a game that combines football and gladiator-style combat. The stakes are high as the outcome of each game affects the fate of entire worlds, including that of Earth.
In 2071, Earth is caught in the middle of a galactic conflict that has altered its climate. The polar shift has placed Moscow in a tropical zone, while New York is frozen. Above the city, the colossal alien spacecraft serves as a stadium for thrilling Cosmoball competitions that attract viewers from all over the galaxy. The game can only be played by athletes—individuals with extraordinary abilities, who are considered gods by the public. The people of the galaxy revere the athletes, as the outcome of their matches impacts the future of entire planets.
The protagonist, Anton, is an ordinary young man who dreams of finding a job to help support his family. However, everything changes when his hidden superhuman abilities are discovered, and he is recruited to play for the Cosmoball team. As Anton begins his journey as a player, he remains unaware of the significant role that fate has in store for him. The final match, in which he participates, will turn into a battle for the future of Earth.
Cast
Yevgeny Romantsov as Anton (Magli sputnik-droid), the Earthling's cosmoball team goalkeeper.
Growing up without a father, he hates cosmoball. Anton thinks only about how to prolong the life of his sick mother and is forced to steal medicines from pharmacies which have turned into strategically important and specially protected facilities. But ironically, it was he who was given the power of teleportation, which he does not yet know how to use, and it is he who will become the leader of the Earth national cosmoball team and the main defender of our planet.
Viktoriya Agalakova as Natalya 'Natasha' (Kisa sputnik-droid) the Earthling's cosmoball team captain.
A young girl who devoted her whole life to sports. Straight, decisive, and courageous, she is used to winning in everything.
Maria Lisovaya as Valaya / Anya
Has shapeshifting abilities. Anton runs into Anya in the slums of tropical Moscow, hiding from the police. Like Anton she also hates cosmoball. Bold and determined, she tries to push him into a strong protest.
Ivan Ivanovich as Pele (Susya sputnik-droid)
Pele is a virtuoso Latin American striker from snowy Brazil. The fastest and strongest on the Earth's national cosmoball team. He is used to taking care of his girls - Natasha and little Fan. Pele's neck and part of his face are covered with an intricate ethnic tattoo.
Yelizaveta Taychenacheva as Fan (Gosha sputnik-droid)
The smallest person on the Earth's national cosmoball team, she can deftly deceive the opponent by sneaking right in front of their nose, but quickly gets tired on the field.
Yevgeny Mironov as Belo, trainer-mentor
The Earth team is coached by an alien genius scientist with long white hair and purple eyes. Belo has his own interest on Earth and in the national team - only he fully understands what kind of evil they are opposing, and this victory in this confrontation became the meaning of his life.
Elena Yakovleva as Anton's mother
Mikhail Yefremov as Vasiliy, a police officer
Mikhail Stenin as Vasiliy's assistant
Dmitry Nazarov as a police chief
Svetlana Permyakova as an evil woman at the stock exchange
Yan Tsapnik as a sports commentator
Gosha Kutsenko as a red-faced security guard
The Amazonian team
Julia Vins as amazon U
Khristina Blokhina as amazon Vo
Valeriya Bukina as amazon Bu
Stanislav Rogachev as amazon Kho
The Siriusian team
Alexey Rakhmanov as captain of the Siriusians
Yevgeny Kosyrev as siriusian Stan
Pavel Dorofeev as a siriusian
Alexey Pavlov as a siriusian
The North American
Wolfgang Cerny as a bearded man with Times Square
Svetlana Ivanova as bearded man's wife
Production
Development
In August 2014, Dzhanik Fayziev announced that he is planning to film a blockbuster titled Cosmoball about a Russian superhero fighting alien invaders, inspired by the comics of the Marvel Universe, and not about the new work of Russian directors who have decided to take the superhero cinema to a completely new level, Russia Today reports.
Fayziev clarified that, according to the plot, people evolved and became part of a galactic society fighting creatures that look like "super-reactive turboballs", therefore battles with them resemble football, hence the name of the film. The nickname of the superhero is Lev Yashin.
Producing was done by Dzhanik Fayziev's company Bonanza Studio, which had success with the films The Turkish Gambit and Furious, a historical fantasy film.
He is also the co-producer and co-author of the script.
Executive producing of the film was entrusted to Sergey Selyanov (ru), director of the CTB Film Company. The preliminary development of the project took almost 5 years.
Maksim Osadchy known for his work on Stalingrad and The Duelist, was hired as cinematographer.
The authors of the script were Twister Murchison, Drew Row, and Andrey Rubanov.
In order to promote the film, main broadcasting companies of Russia - Channel One, Russia-1 and CTC Media joined forces.
Casting
The main roles in the film were performed by sports-men instead of professional actors. Lead actor Yevgeny Romantsov graduated from the Moscow State Academy of Physical Culture (majoring in theory and methodology of football and hockey). Romantsov previously took part in productions of the Gogol Center. Russian actress Viktoriya Agalakova (née Glukhikh) studied ballet, acrobatics, and choreography, which proved to be useful when filming dynamic scenes on suspensions. Agalakova works at the Saint Petersburg State Theater of Musical Comedy. They were accompanied by аctress Maria Lisovaya, a graduate of the Boris Shchukin Theatre Institute.
The fourth unknown actress who joined them was the winner of international competitions in rhythmic gymnastics Yelizaveta "Liza" Taychenacheva, an actress who previously competed in biathlon and the Children's teams of Youth Sports Schools "Youth of Moscow". They were all cast because of their sporting past.
They were joined by famous actors such as Yevgeny Mironov, Elena Yakovleva, Mikhail Yefremov, and others.
Director Dzhanik Fayziev's film is one of the most ambitious, expensive, and high-tech projects of all that is being shot in Russia. On the walls of the pavilion, there is a blue chroma key on which backgrounds will be drawn. In one frame with live actors - virtual characters, drawn from scratch or with the help of digital capture technology acting game motion capture.
Filming
Principal photography commenced in the scenery on the territory of Mosfilm Studios in Moscow, and lasted from June 2 to mid-September 2017.
On an area of over 3,500 square meters built transforming the scenery of the streets and interiors of post-apocalyptic Moscow, with thousands of props created by the artists specifically for the film.
In the shooting involved up to 500 actors for crowd scenes, and for each a unique costume was stitched.
In the Studio, costume designers were delivered 1.5 tons of items lightweight summer clothing from India were delivered.
When working with images, sophisticated prosthetics were used: one of the characters, Valaya — is in a suit covered with silicone pads throughout her whole body. This took seven hours to create for the make-up-artist.
Post-production
For the post-production of visual effects is engaged in the studio Main Road Post, according to the company's general director Arman Yakhin.
One of the biggest challenges of the project was a large number of digital characters (over 50), both completely virtual and recreated using motion capture of actors.
For this work, the walls of the Mosfilm pavilions were covered with blue chroma key, on which the backgrounds were painted.
In the first case, the actor on the court interacts with the dimensional toy, in the second - with the actor in a blue suit with inertial sensors. Through the use of augmented reality technology, the director could see on his monitor a full-fledged image immediately, that is, instead of a blue person - an alien.
Additional work on creating a unique world of the picture, was done by visual effects specialists from the studio Main Road Post.
Music
The music score was composed by Italian musician Tony Neiman.
Release
The film's original premiere date was previously scheduled for January 24, 2019. It was delayed because on this date the creative group had some difficulties.
In September 2018, it was announced that the release date was postponed to October 17, 2019. As previously assumed, the picture would be presented to viewers on August 27, 2020. On its previously scheduled release date, its former slot was taken by Maleficent: Mistress of Evil.
The film's premiere was held on August 25, 2020, at the cinema "Karo 11 October" in Moscow, and was released in cinemas in the following weekend. This was the first major Russian film release after the quarantine, and it was scheduled to be released in the Russian Federation by Nashe Kino in RealD 3D format on August 27, 2020.
Marketing
The first teaser for the film was shown on September 30, 2017, during the IgroMir / Comic-Con Russia festival, when the director presented the film to the audience.
Reception
Box office and VOD
The film became the first major national blockbuster in Russia to be released after the effects of the outbreak of the coronavirus in Russia that forced a restriction on the number of viewers in cinemas, and put in the amount of 106.6 million Russian rubles (about $1.4 million) compared to a budget of 786,4 million rubles.
The film was released on digital rental in Russia on October 9, 2020, at the KinoPoisk HD online cinema.
Critical response
The film received mostly low to average ratings from Russian critics, who noted the weak storyline and expressionless dialogues of the characters.
Nikolai Kornatsky from "Film Art" wrote that with the visual part, everything is also not cosmic. The graphics themselves - unprecedented for our cinema - are in no way inferior to either Valerian (2017) or Guardians of the Galaxy (2014). But this whole huge, loud and populous world all too often evokes a sense of déjà vu.
Anton Dolin noted that the film lacks a clearly invented world, the laws, and background of which the authors begin to explain to the audience from the first seconds, but they continue to struggle until the very end. An interesting plot, since three stories - about Dr. Frankenstein and the monster he spawned, about a naive boy who will eventually grow into a messiah, and about a sports competition - do not fit well with each other.
References
External links
Official website at the CTB Film Company
Cosmoball - Youtube
2020s Russian-language films
2020s superhero films
2020 science fiction action films
2020s sports films
2020s science fiction adventure films
2020 3D films
Russian superhero films
Teen superhero films
Russian science fiction action films
Russian action adventure films
Russian science fiction adventure films
Russian sports films
Teen sports films
Russian 3D films
Russian association football films
Russian superheroes
Social science fiction films
Animated films set on fictional planets
Films set in the future
Films about extraterrestrial life
Films set in Moscow
Films set in Russia
Films scored by Yuri Poteyenko
Films about alien invasions
Space adventure films
Space opera films
2020s dystopian films
Fiction about generation ships
Films about computing
Films about competitions
Earth in film
Fiction about intergalactic travel
Films using motion capture
Films with live action and animation
Mosfilm films
Films shot in Moscow
Films shot in Russia
Russian post-apocalyptic films
Russian dystopian films
Russian-language action adventure films | Cosmoball | [
"Technology"
] | 3,048 | [
"Works about computing",
"Films about computing"
] |
55,958,532 | https://en.wikipedia.org/wiki/Amazon%20Neptune | Amazon Neptune is a managed graph database product published by Amazon.com. It is used as a web service and is part of Amazon Web Services (AWS). It was announced on November 29, 2017. Amazon Neptune supports popular graph models property graph and W3C's RDF, and their respective query languages Apache TinkerPop's Gremlin, openCypher, and SPARQL, including other Amazon Web Services products.
Amazon Neptune general availability (GA) was announced on May 30, 2018 and is currently available in 22 regions. Neptune is HIPAA eligible. On December 12, 2018, it was announced that Amazon Neptune was in-scope for Payment Card Industry Data Security Standard, and ISO compliance programs.
History
Amazon Neptune is based on Blazegraph. Amazon acquired the Blazegraph developers and the Blazegraph open source development was essentially stopped in April 2018.
Features
External support
Amazon Neptune supports the open source Apache TinkerPop Gremlin graph traversal language, openCypher query language for property graphs, and the W3C standard Resource Description Framework's (RDF) SPARQL query language. All three can be used on the same Neptune instance, and allows the user to build queries to navigate highly connected data sets and provides high performance for both graph models. Neptune also uses other AWS product features such as those of Amazon S3, Amazon EC2 and Amazon CloudWatch.
Security
All Amazon Neptune database clusters are created and stored in an Amazon Virtual Private Cloud (VPC), which allows the user to isolate their database in their own private network. Using Neptune's VPC configuration, the user can configure firewall settings to their needs in order to control network access to database instances. Amazon Neptune is integrated with AWS Identity and Access Management (IAM), which allows the user to create AWS IAM groups and control the actions that the groups and other AWS IAM users can do. Neptune allows the user to encrypt databases using keys created through AWS Key Management Service (KMS). A database instance running with Neptune Encryption, encrypts all of the stored data, backups, snapshots and replicas in the same cluster. Amazon Neptune allows the user to use HTTPS to encrypt data during its transfer to and from clients or Neptune service endpoints using Transport Layer Security (TLS).
Storage
The data is stored in a cluster volume, a virtual volume utilizing SSD drives. These sizes of these volumes are dynamic, they increase depending how much data is stored in the database, with a maximum of 64 TB. The Amazon Neptune SLA policy is designed to offer a monthly uptime percentage greater that of 99.9%, increasing database performance and availability by integrating the engine with a virtual storage based on SSD drives, that are specially made for database workloads. Neptune maintains copies of the user's data in multiple Availability Zones. In case of failures, Neptune automatically detects any failed segments in a disk volume and repairs them.
Availability
Neptune is now generally available in the US East (N. Virginia), US East (Ohio), US West (Oregon), US West (N. California), Canada (Central), AWS GovCloud (US-West), AWS GovCloud (US-East), Europe (Ireland), Europe (London), Europe (Frankfurt), Europe (Stockholm), Europe (Paris), South America (São Paulo), Asia Pacific (Singapore), Asia Pacific (Sydney), Asia Pacific (Tokyo), Asia Pacific (Mumbai), Asia Pacific (Seoul), Asia Pacific (Hong Kong), China (Ningxia), China (Beijing), Operated by NWCD, and Middle-East (Bahrain) AWS regions.
Pricing
Pricing is determined by AWS regions, with each region having different prices for the available services.
On-Demand Instance Pricing lets the user pay only for what instance they use by the hour instead of a fixed sum. The price also differs depending on the instance class. Similarly, the user only pays for the storage consumed by the database, with no payments in advance. The price is based on the storage rate and I/O rate, which are billed in GB per month and per million request increments respectively. This pricing model is beneficial to short-term and small-scale projects and is available in all AWS regions. The price for backup storage is also billed in per GB-month increments albeit at different rates. Data Transfer is priced in per GB increments, the amount depends on whether the data is transferred in or out of Amazon Neptune and how much data is transferred per month (TB per Month).
Application
On September 12, 2018, it was announced that Neptune achieved HIPAA eligibility enabling it to process data sets containing protected health information (PHI). On December 12, 2018, it was announced that Amazon Neptune was in-scope for Payment Card Industry Data Security Standard, ISO 9001, ISO 27001, ISO 27017, and ISO 27018 compliance programs. The user can use Amazon Neptune in applications that are subject to PCI compliance or require ISO certification. On May 17, 2019, it was announced that Neptune achieved SSAE 16 eligibility
Neptune powers graph use cases such as recommendation engines, fraud detection, knowledge graphs, drug discovery, network security, and social networking.
Notable users
Some notable customers of Amazon Neptune include, Samsung Electronics, Pearson, Intuit, Siemens, AstraZeneca, FINRA, LifeOmic, Blackfynn, and Amazon Alexa
See also
Triplestore
Structured storage
NoSQL
References
Further reading
External links
Amazon Neptune official home page
Amazon Web Services
Cloud databases
Distributed data stores
Structured storage
NoSQL products
Internet properties established in 2016
Graph databases | Amazon Neptune | [
"Mathematics"
] | 1,183 | [
"Graph databases",
"Mathematical relations",
"Graph theory"
] |
55,958,638 | https://en.wikipedia.org/wiki/Multifidelity%20simulation | Multifidelity (or multi-fidelity) methods leverage both low- and high-fidelity data in order to maximize the accuracy of model estimates, while minimizing the cost associated with parametrization. They have been successfully used in impedance cardiography, wing-design optimization, robotic learning, computational biomechanics, and have more recently been extended to human-in-the-loop systems, such as aerospace and transportation. They include both model-based methods, where a generative model is available or can be learned, in addition to model-free methods, that include regression-based approaches, such as stacked-regression. A more general class of regression-based multi-fidelity methods are Bayesian approaches, e.g. Bayesian linear regression, Gaussian mixture models, Gaussian processes, auto-regressive Gaussian processes, or Bayesian polynomial chaos expansions.
The approach used depends on the domain and properties of the data available, and is similar to the concept of metasynthesis, proposed by Judea Pearl.
Data fidelity spectrum
The fidelity of data can vary along a spectrum between low- and high-fidelity. The next sections provide examples of data across the fidelity spectrum, while defining the benefits and limitations of each type of data.
Low fidelity data (LoFi)
Low-fidelity data (LoFi) includes any data that was produced by a person or Stochastic Process that deviates from the real-world system of interest. For example, LoFi data can be produced by models of a physical system that use approximations to simulate the system, rather than modeling the system in an exhaustive manner.
Moreover, in human-in-the-loop (HITL) situations the goal may be to predict the impact of technology on expert behavior within the real-world operational context. Machine learning can be used to train statistical models that predict expert behavior, provided that an adequate amount of high-fidelity (i.e., real-world) data are available or can be produced.
LoFi benefits and limitations
In situations when there is not an adequate amount of high-fidelity data available to train the model, low-fidelity data can sometimes be used. For example, low-fidelity data can be acquired by using a distributed simulation platform, such as X-Plane, and requiring novice participants to operate in scenarios that are approximations of the real-world context. The benefit of using low-fidelity data is that they are relatively inexpensive to acquire, so it is possible to elicit larger amounts of data. However, the limitation is that the low-fidelity data may not be useful for predicting real-world expert (i.e., high-fidelity) performance due to differences between the low-fidelity simulation platform and the real-world context, or between novice and expert performance (e.g., due to training).
High-fidelity data (HiFi)
High-fidelity data (HiFi) includes data that was produced by a person or Stochastic Process that closely matches the operational context of interest. For example, in wing design optimization, high-fidelity data uses physical models in simulation that produce results that closely match the wing in a similar real-world setting. In HITL situations, HiFi data would be produced from an operational expert acting in the technological and situational context of interest.
HiFi benefits and limitations
An obvious benefit of utilizing high-fidelity data is that the estimates produced by the model should generalize well to the real-world context. However, these data are expensive in terms of both time and money, which limits the amount of data that can be obtained. The limited amount of data available can significantly impair the ability of the model to produce valid estimates.
Multifidelity methods (MfM)
Multifidelity methods attempt to leverage the strengths of each data source, while overcoming the limitations. Although small to medium differences between low- and high-fidelity data are sometimes able to be overcome by multifidelity models, large differences (e.g., in KL divergence between novice and expert action distributions) can be problematic leading to decreased predictive performance when compared to models that exclusively relied on high-fidelity data.
Multifidelity models enable low-fidelity data to be collected on different technology concepts to evaluate the risk associated with each concept before actually deploying the system.
Bayesian auto-regressive Gaussian processes
In an auto-regressive model of Gaussian processes (GP), each level of output fidelity, , where a higher denotes a higher fidelity, is modeled as a GP, , which can be expressed in terms of the previous level's GP, , a proportionality constant and a "difference-GP" as follows:
The scaling constant that quantifies the correlation of levels and , and can generally depend on .
Under the assumption, that all information about a level is contained in the data corresponding to the same pivot point at level as well as , semi-analytical first and second moments are feasible. This assumption formally is
I.e. given a data at on level , there is no further information about level to extract from the data on level .
References
Data modeling
Estimation methods | Multifidelity simulation | [
"Engineering"
] | 1,057 | [
"Data modeling",
"Data engineering"
] |
55,958,732 | https://en.wikipedia.org/wiki/Data%20query%20language | Data query language (DQL) is part of the base grouping of SQL sub-languages. These sub-languages are mainly categorized into four categories: a data query language (DQL), a data definition language (DDL), a data control language (DCL), and a data manipulation language (DML). Sometimes a transaction control language (TCL) is argued to be part of the sub-language set as well.
DQL statements are used for performing queries on the data within schema objects. The purpose of DQL commands is to get the schema relation based on the query passed to it.
Although often considered part of DML, the SQL SELECT statement is strictly speaking an example of DQL. When adding FROM or WHERE data manipulators to the SELECT statement the statement is then considered part of the DML.
Related language types
Data definition language
Data manipulation language
Data control language
Transactional control language
References
Data modeling
SQL
Database management systems | Data query language | [
"Engineering"
] | 199 | [
"Data modeling",
"Data engineering"
] |
55,958,743 | https://en.wikipedia.org/wiki/Caldanaerobius | Caldanaerobius is a genus of thermophilic, obligately anaerobic bacteria from the family of Thermoanaerobacteraceae.
Phylogeny
The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI)
See also
List of bacterial orders
List of bacteria genera
References
Further reading
Thermoanaerobacterales
Bacteria genera
Thermophiles
Anaerobes | Caldanaerobius | [
"Biology"
] | 106 | [
"Bacteria",
"Anaerobes"
] |
55,958,870 | https://en.wikipedia.org/wiki/Caldanaerobius%20fijiensis | Caldanaerobius fijiensis is a thermophilic, obligately anaerobic and spore-forming bacterium from the genus of Caldanaerobius which has been isolated from a hot spring in Fiji.
References
Thermoanaerobacterales
Bacteria described in 2008
Thermophiles
Anaerobes | Caldanaerobius fijiensis | [
"Biology"
] | 69 | [
"Bacteria",
"Anaerobes"
] |
55,958,942 | https://en.wikipedia.org/wiki/Caldanaerobius%20polysaccharolyticus | Caldanaerobius polysaccharolyticus is a Gram-positive thermophilic, anaerobic, non-spore-forming bacterium from the genus of Caldanaerobius which has been isolated from organic waste leachate from Hoopeston in the United States.
References
Thermoanaerobacterales
Bacteria described in 2001
Thermophiles
Anaerobes | Caldanaerobius polysaccharolyticus | [
"Biology"
] | 82 | [
"Bacteria",
"Anaerobes"
] |
55,959,002 | https://en.wikipedia.org/wiki/Caldanaerobius%20zeae | Caldanaerobius zeae is a Gram-positive thermophilic, anaerobic, non-spore-forming bacterium from the genus of Caldanaerobius which has been isolated from organic waste leachate in Hoopeston in the United States.
References
Thermoanaerobacterales
Bacteria described in 2001
Thermophiles
Anaerobes | Caldanaerobius zeae | [
"Biology"
] | 77 | [
"Bacteria",
"Anaerobes"
] |
55,959,362 | https://en.wikipedia.org/wiki/Autocorrelation%20%28words%29 | In combinatorics, a branch of mathematics, the autocorrelation of a word is the set of periods of this word. More precisely, it is a sequence of values which indicate how much the end of a word looks likes the beginning of a word. This value can be used to compute, for example, the average value of the first occurrence of this word in a random string.
Definition
In this article, A is an alphabet, and a word on A of length n. The autocorrelation of can be defined as the correlation of with itself. However, we redefine this notion below.
Autocorrelation vector
The autocorrelation vector of is , with being 1 if the prefix of length equals the suffix of length , and with being 0 otherwise. That is indicates whether .
For example, the autocorrelation vector of is since, clearly, for being 0, 1 or 2, the prefix of length is equal to the suffix of length . The autocorrelation vector of is since no strict prefix is equal to a strict suffix. Finally, the autocorrelation vector of is 100011, as shown in the following table:
Note that is always equal to 1, since the prefix and the suffix of length are both equal to the word . Similarly, is 1 if and only if the first and the last letters are the same.
Autocorrelation polynomial
The autocorrelation polynomial of is defined as . It is a polynomial of degree at most .
For example, the autocorrelation polynomial of is and the autocorrelation polynomial of is . Finally, the autocorrelation polynomial of is .
Property
We now indicate some properties which can be computed using the autocorrelation polynomial.
First occurrence of a word in a random string
Suppose that you choose an infinite sequence of letters of , randomly, each letter with probability , where is the number of letters of . Let us call the expectation of the first occurrence of ? in ? . Then equals . That is, each subword of which is both a prefix and a suffix causes the average value of the first occurrence of to occur letters later. Here is the length of v.
For example, over the binary alphabet , the first occurrence of is at position while the average first occurrence of is at position . Intuitively, the fact that the first occurrence of is later than the first occurrence of can be explained in two ways:
We can consider, for each position , what are the requirement for 's first occurrence to be at .
The first occurrence of can be at position 1 in only one way in both case. If starts with . This has probability for both considered values of .
The first occurrence of is at position 2 if the prefix of of length 3 is or is . However, the first occurrence of is at position 2 if and only if the prefix of of length 3 is . (Note that the first occurrence of in is at position 1.).
In general, the number of prefixes of length such that the first occurrence of is at position is smaller for than for . This explain why, on average, the first arrive later than the first .
We can also consider the fact that the average number of occurrences of in a random string of length is . This number is independent of the autocorrelation polynomial. An occurrence of may overlap another occurrence in different ways. More precisely, each 1 in its autocorrelation vector correspond to a way for occurrence to overlap. Since many occurrences of can be packed together, using overlapping, but the average number of occurrences does not change, it follows that the distance between two non-overlapping occurrences is greater when the autocorrelation vector contains many 1's.
Ordinary generating functions
Autocorrelation polynomials allows to give simple equations for the ordinary generating functions (OGF) of many natural questions.
The OGF of the languages of words not containing is .
The OGF of the languages of words containing is .
The OGF of the languages of words containing a single occurrence of , at the end of the word is .
References
Formal languages
Combinatorics on words | Autocorrelation (words) | [
"Mathematics"
] | 832 | [
"Formal languages",
"Mathematical logic",
"Combinatorics on words",
"Combinatorics"
] |
55,959,454 | https://en.wikipedia.org/wiki/Intensity-duration-frequency%20curve | An intensity-duration-frequency curve (IDF curve) is a mathematical function that relates the intensity of an event (e.g. rainfall) with its duration and frequency of occurrence. Frequency is the inverse of the probability of occurrence. These curves are commonly used in hydrology for flood forecasting and civil engineering for urban drainage design. However, the IDF curves are also analysed in hydrometeorology because of the interest in the time concentration or time-structure of the rainfall, but it is also possible to define IDF curves for drought events. Additionally, applications of IDF curves to risk-based design are emerging outside of hydrometeorology, for example some authors developed IDF curves for food supply chain inflow shocks to US cities.
Mathematical approaches
The IDF curves can take different mathematical expressions, theoretical or empirically fitted to observed event data. For each duration (e.g. 5, 10, 60, 120, 180 ... minutes), the empirical cumulative distribution function (ECDF), and a determined frequency or return period is set. Therefore, the empirical IDF curve is given by the union of the points of equal frequency of occurrence and different duration and intensity Likewise, a theoretical or semi-empirical IDF curve is one whose mathematical expression is physically justified, but presents parameters that must be estimated by empirical fits.
Empirical approaches
There is a large number of empirical approaches that relate the intensity (I), the duration (t) and the return period (p), from fits to power laws such as:
Sherman's formula, with three parameters (a, c and n), which are a function of the return period, p:
Chow's formula, also with three parameters (a, c and n), for a particular return period p:
Power law according to Aparicio (1997), with four parameters (a, c, m and n), already adjusted for all return periods of interest:
In hydrometeorology, the simple power law (taking ) is used as a measure of the time-structure of the rainfall:
where is defined as an intensity of reference for a fixed time , i.e. , and is a non-dimensional parameter known as n-index. In a rainfall event, the equivalent to the IDF curve is called Maximum Averaged Intensity (MAI) curve.
Theoretical approaches
To get an IDF curves from a probability distribution, it is necessary to mathematically isolate the total amount or depth of the event, which is directly related to the average intensity and the duration , by the equation , and since the return period is defined as the inverse of , the function is found as the inverse of , according to:
Power law with the return period, derived from the Pareto distribution, for a fixed duration :
where the Pareto distribution constant has been redefined as, since it is a valid distribution for a specific duration of the event, it has been taken as.
Function derived from the generalized Pareto distribution, for a given duration :
Note that for y , the generalized Pareto distribution retrieves the simple form of the Pareto distribution, with . However, with the exponential distribution is retrieved.
Function deduced from the Gumbel distribution and the opposite Gumbel distribution, for a given duration :
References
Empirical process
Mathematical analysis
Hydrology and urban planning | Intensity-duration-frequency curve | [
"Mathematics",
"Environmental_science"
] | 669 | [
"Mathematical analysis",
"Hydrology and urban planning",
"Hydrology"
] |
55,959,933 | https://en.wikipedia.org/wiki/Bladelet%20%28impeller%29 | Used in centrifugal impeller terminology, bladelets are the more 'Metro' version of the common engineering description of splitters (shorter blades that do not extend into the centre of the impeller). The term is thought to have originated among the middle-upper-level management at medical device engineering companies, near the turn of the millennium.
Marine propulsion | Bladelet (impeller) | [
"Engineering"
] | 75 | [
"Marine propulsion",
"Marine engineering"
] |
55,960,563 | https://en.wikipedia.org/wiki/Autogenous%20welding | Autogenous welding is a form of welding in which the filler material is either supplied by melting the base material or is of identical composition. The weld may be formed entirely by melting parts of the base metal, and no additional filler rod is used.
There is some variation in the use of this term. Those bodies concerned with teaching the craft skill of welding tend to define it as using no filler rod, i.e. the technique is based purely on the base metal. Those concerned with the welded joint's metallurgy may make no distinction between a filler rod and the base metal, provided that the final metallurgy is identical.
Most welding processes may be either autogenous or use additional filler. Some are characteristically autogenous and avoid filler. Some arc welding processes, including such major process such as manual metal arc (stick) welding and MAGS (wire-feed) welding, cannot be used autogenously, as they rely on the consumption of a filler rod to provide the arc.
Some processes are typically autogenous. These include some gas welding processes such as lead burning (although fillers may optionally be used) and oxy-acetylene welding in some positions, such as seam welding the edges of two overlapping sheets. Resistance welding, both spot welding and seam welding, is inherently autogenous, as there is no convenient way to apply a filler. Friction and laser welding have similar restrictions.
Some alloys are prone to changing their composition when heated, particularly a loss of zinc from brass by its evaporation as vapour. In these cases, an excess of 2–3% extra zinc may be provided in the filler rod to compensate. Silicon may also be used as an additive to reduce this loss.
A few materials, such as the HY-80 series of high-strength steels, require a non-autogenous process to control their metallurgy. However, advanced processes, such as hybrid laser arc welding, have been used to achieve the same effect autogenously.
References
Welding | Autogenous welding | [
"Engineering"
] | 425 | [
"Welding",
"Mechanical engineering"
] |
55,961,308 | https://en.wikipedia.org/wiki/Thomas%20Stewart%20Patterson | Thomas Stewart Patterson FRSE LLD (1872–1949) was a Scottish organic chemist.
Early life and education
He was born in Greenock, in 1872, but his family came to Edinburgh in his youth and he was then educated at Merchiston Castle School. He then studied Chemistry at Andersonian college in Glasgow under Prof William Dittmar.
He then went to Heidelberg where he gained his first doctorate (PhD) in 1896. He was greatly influenced there by Victor Meyer. Returning to Britain, he was the first Priestley scholar at the University of Birmingham. In 1904, he began lecturing in Chemistry at Glasgow University. In 1919, he became the first Gardiner chair of Organic Chemistry.
Career
In 1919, he was elected a Fellow of the Royal Society of Edinburgh. His proposers were Alexander Gray, George Alexander Gibson, John Glaister, Diarmid Noel Paton, Ralph Stockman, Thomas Hastie Bryce, Robert Muir, Frederick Orpen Bower and Robert Alexander Houston. He resigned from the Society in 1931.
He retired in 1942 and died in 1949.
Publications
An International Language for Chemistry (1924)
References
1872 births
1949 deaths
British organic chemists
20th-century Scottish chemists
People educated at Merchiston Castle School
People from Greenock
Academics of the University of Glasgow
Fellows of the Royal Society of Edinburgh | Thomas Stewart Patterson | [
"Chemistry"
] | 268 | [
"Organic chemists",
"British organic chemists"
] |
55,962,195 | https://en.wikipedia.org/wiki/MINERVA-Australis | MINERVA-Australis (stylized MINERVA-Australis) is a dedicated exoplanet observatory, operated by the University of Southern Queensland, in Queensland, Australia. The facility is located at USQ's Mount Kent Observatory, and saw first light in quarter two 2018. Commissioning of the facility was completed in mid-2019, and the facility was officially launched on 23 July 2019.
The facility follows the innovative model first deployed in the northern hemisphere's Miniature Exoplanet Radial Velocity Array (MINERVA), a northern hemisphere exoplanet facility located at the U.S. Fred Lawrence Whipple Observatory at Mt. Hopkins, Arizona. MINERVA-Australis is being used to perform follow-up and characterisation observations of exoplanets discovered by NASA's Transiting Exoplanet Survey Satellite (TESS), which was launched in April, 2018.
The project's principal investigator is USQ astronomer Rob Wittenmyer, who leads a consortium of partners from institutions across the world (UNSW Australia; Nanjing University; University of California, Riverside; MIT; George Mason University; University of Louisville; University of Texas at Austin; University of Florida).
Science objectives
The primary mission of MINERVA-Australis is to support observations carried out by the NASA TESS spacecraft, providing dedicated follow-up and characterisation of newly discovered exoplanets. During commissioning, the facility was used to pursue targets of opportunity, and to carry out work extending the baseline of the Anglo-Australian Planet Search program. MINERVA-Australis allows researchers to obtain precise radial velocity observations for target stars, enabling the masses of planets discovered by the TESS spacecraft to be directly measured, and has recently demonstrated a radial velocity precision of approximately 1 m/s.
In addition to providing high precision velocity measurements, MINERVA-Australis will also offer high-cadence photometric observations. This is to facilitate direct follow-up transit observations of TESS candidate planets (particularly those in fields from which TESS has moved on). It can also enable the observation of occultation events and other transient targets of opportunity.
During commissioning, observations made by the MINERVA-Australis array contributed to the discovery of 13 new exoplanets, working in collaboration with researchers at institutions across the globe.
The facility
MINERVA-Australis currently consists of four PlaneWave CDK700 telescopes,. Five CDK700's were available for the period July 2019 - April 2020, while a donated CDK700 telescope was waiting for another project to start. These 0.7 m telescopes have two ports, allowing each to be used for either spectroscopic or photometric observations. Each telescope sits in its own automated clam-shell Astrohaven dome, distributed in an approximate semi-circle around the main observatory building.
Photometric work is to be carried out using Andor cameras, with 2k x 2k back-illuminated CCDs with 15 μm pixels. These cameras offer an effective field of view greater than 20 arcminutes.
The telescopes are connected by optical fibre to a stabilised, R = 75,000 echelle spectrograph, covering the wavelengths 480 - 630nm, designed by KiwiStar Optics. The spectrograph uses simultaneous calibration in a separate fibre. Prior to 2020, the simultaneous calibration was provided by a Thorium-Argon lamp. Because of the wavelength range and the very low scattered light the simultaneous calibration source is now supplied by a Tungsten slit-flat lamp backlighting an iodine cell. This is a different approach to the normal iodine cell method that passes the starlight through an iodine cell.
See also
List of telescopes of Australia
References
External links
University of Louisville and Minerva Australis at Mt. Kent
Astronomical instruments
Astronomical surveys
Exoplanet search projects
Optical telescopes | MINERVA-Australis | [
"Astronomy"
] | 783 | [
"Exoplanet search projects",
"Astronomical surveys",
"Works about astronomy",
"Astronomical instruments",
"Astronomy projects",
"Astronomical objects"
] |
55,962,963 | https://en.wikipedia.org/wiki/NGC%205640 | NGC 5640 is a spiral galaxy approximately 660 million light-years away from Earth in the constellation of Camelopardalis. It was discovered by British astronomer William Herschel on December 20, 1797.
Supernova SN 1996ah
Supernova SN 1996ah was discovered in NGC 5640 on June 6, 1996 by J. Mueller, who was using the 1.2-m Oschin Schmidt telescope in the course of the second Palomar Sky Survey.
SN 1996ah had magnitude about 18 and was located southwest of the centre of NGC 5640 (coordinates: RA 14h20m39.020s, DEC +80d07m21.00s, J2000.0). It was classified as type Ia supernova.
See also
List of NGC objects (5001–6000)
References
External links
SEDS
Spiral galaxies
Camelopardalis
5640
51263
Astronomical objects discovered in 1797
Discoveries by William Herschel | NGC 5640 | [
"Astronomy"
] | 192 | [
"Camelopardalis",
"Constellations"
] |
55,963,154 | https://en.wikipedia.org/wiki/SN%201996ah | SN 1996ah was a supernova located in the spiral galaxy NGC 5640 in the constellation of Camelopardalis. It was discovered on June 6, 1996 by American astronomer Jean Mueller, who was using the 1.2-m Oschin Schmidt telescope in the course of the second Palomar Sky Survey.
SN 1996ah had magnitude about 18 and was located 5" west and 1" south of the center of NGC 5640. It was classified as type Ia supernova.
See also
Supernova
NGC 5640
Camelopardalis (constellation)
References
Supernovae
19960606
Camelopardalis | SN 1996ah | [
"Chemistry",
"Astronomy"
] | 126 | [
"Supernovae",
"Astronomical events",
"Constellations",
"Camelopardalis",
"Explosions"
] |
55,963,248 | https://en.wikipedia.org/wiki/Dengvaxia%20controversy | The Dengvaxia controversy () occurred in the Philippines when the dengue vaccine Dengvaxia was found to increase the risk of disease severity for some people who had received it.
A vaccination program run by the Philippine Department of Health (DOH) administered Sanofi Pasteur's Dengvaxia to schoolchildren. The program was stopped when Sanofi Pasteur advised the government that the vaccine could put previously uninfected people at a somewhat higher risk of a severe case of dengue fever through antibody-dependent enhancement. A political controversy erupted over whether the program was run with sufficient care and who should be held responsible for the alleged harm to the vaccinated children.
In late November 2017, the DOH suspended the school-based vaccination program. The DOH subsequently banned the vaccine's use and sale in the Philippines. The scare caused by the controversy has been suggested as a factor in the country's loss of confidence in vaccines and low immunization rates, resulting in an infectious disease crisis in the country in 2019, including a measles outbreak.
Events
On December 1, 2015, former President Benigno Aquino III met with executives of Sanofi Pasteur in a courtesy call in Paris, making the Philippines the first Asian country to approve the commercial sale of Dengvaxia.
In April 2016, the DOH launched the dengue vaccination campaign in Central Luzon, Calabarzon and Metro Manila, where about 700,000 individuals received at least one dose of the vaccine. The government paid P3.5-billion for the vaccine.
On November 29, 2017, French drugmaker Sanofi Pasteur released a statement stating that their dengue vaccine, Dengvaxia, posed risk to individuals vaccinated without having a prior dengue infection. Soon after, the Philippine Department of Health (DOH) suspended the vaccination on FCS program based in schools owing to the said concern, with DOH Secretary Francisco Duque saying "In the light of this new analysis, the DOH will place the dengue vaccination on hold while review and consultation is ongoing with experts, key stakeholders and the World Health Organization." On December 2, 2017, the government of Makati immediately suspended its anti-dengue vaccination drive following its statement.
In its statement, pharmaceutical company Sanofi Pasteur reported concerns that Filipinos, mostly schoolchildren, could potentially be at risk of a more severe disease, where the recipient of the vaccine had not had a previous dengue infection; however, a medical director of Sanofi said that the dengue vaccination would not cause "severe dengue." On December 4, 2017, Sanofi also denied that they made Filipinos into “guinea pigs,” explaining that the vaccine program was conducted by the DOH and not them. Senator JV Ejercito, chair of the Senate Committee on Health and Demography, sought to identify by January 2018 whether there was an irregularity in the procurement of the vaccine, while Senator Risa Hontiveros urged the government to address the health threats posed by the vaccine. The Food and Drug Administration of the Philippines ordered Sanofi to stop distributing of Dengvaxia into the country. Former Health Secretary Janette Garin said she welcomed the investigation which will be conducted by the Philippine Department of Justice. Presidential spokesperson Harry Roque told the media that 10 percent of the 733,000 to 830,000 schoolchildren were at risk of dengue infection. Since then, the Philippine Department of Education has closely monitored the students who have been injected by the vaccine. Hontiveros said that Sanofi should take liability for the medical expenses of those who contracted severe dengue fever after receiving doses of the vaccine.
Sanofi representative Thomas Triomphe "was forced to apologize" during the House of Representatives hearing on the Dengvaxia dengue vaccine. Former President Benigno Aquino III, who approved the vaccination program in 2016, expressed interest in attending the Senate hearing. On December 16, Aquino told reporters that "With the announcement of Sanofi and the reactions to it, there has been a lot of tension building up and I think it is incumbent upon me even as a citizen to try and allay certain fears, to put it in the proper perspective, to put it on the proper level."
Secretary Duque reminded the public, especially parents, that "the vaccine is not a 'standalone' preventive measure against dengue." On December 15, 2017, former Education and Skills Development chief Augusto Syjuco Jr filed "mass murder and plunder" complaints against Aquino and former health secretary Janette Garin over the controversial vaccination program. Former health secretary Enrique Ona blamed his successor Janette Garin, who advised former president Benigno Aquino lll to purchase the Dengvaxia.
On February 2, 2018, the University of the Philippines-Philippine General Hospital (UP-PGH) issued a report stating that three out of 14 children who died after receiving Dengvaxia indicated dengue despite immunization. On February 3, a group of doctors, including former health secretary Esperanza Cabral, urged the Public Attorney's Office (PAO) to stop conducting autopsies.
On February 5, 2018, during a probe at the House of Representatives, mothers of children who took part in a mass vaccination program confronted Garin, screaming at her and accusing her of killing their children. The women would later admit to the media that none of their children died after vaccination.
On February 21, 2018, Senator Richard Gordon said that the DOH must be liable for the controversy. On March 13, Senator Gordon formally terminated the investigation of the controversy.
On February 26, 2018, Aquino appeared for the first time at a House inquiry about the controversy; he said that the controversy has been "politicized," but the Malacañang Palace distanced itself from Aquino's allegations.
On February 27, 2018, the opposition Representatives such as Gary Alejano of Magdalo and Edcel Lagman of Albay urged President Rodrigo Duterte to intervene in the dispute between the PAO and DOH. On March 3, about 200 families of Dengvaxia vaccines joined the advocacy run held in Quezon Memorial Circle.
In 2018, Dengvaxia was approved in Europe and US in 2019, only for use in people who have been infected with dengue virus before and who live in areas where this infection is endemic.
Charges
On April 5, 2018, Public Attorney's Office filed the criminal charges (reckless imprudence resulting in homicide under Article 365 of the Revised Penal Code and violation of Republic Act No. 9745 (Anti-Torture Act) and torture) against the Former Health Secretary Janette Garin and other former officials. However, Garin said that the charges have no basis and vowed to file a counter-charge against PAO. The families of four children — Aejay Bautista (11), Lenard Baldonado (10), Zandro Colite (11), and Angelica Pestilos (10), whose deaths had been linked to Dengvaxia — also filed the charges.
On April 19, 2018, PAO filed criminal complaints before the Department of Justice (DOJ), including the incumbent Health Secretary Francisco Duque III, following the death of the 13-year-old girl after receiving Dengvaxia on November 17, 2017. Duque described the charges against him as "malicious and oppressive" and he also said that he has nothing to do with the implementation of the dengue immunization program since he was seated as the secretary in October 2017.
Gordon's draft report
On April 15, 2018, Gordon said he expected at least 10 senators to sign his report holding former President Benigno Aquino III and other officials liable. Senator Panfilo Lacson will not sign the report due to "unreasonable comments" about him. On April 17, Aside from Gordon, who already signed the report, Senators Ralph Recto, Manny Pacquiao, Win Gatchalian, Tito Sotto, Gregorio Honasan, Migz Zubiri, JV Ejercito, Nancy Binay, and Grace Poe have signed. On April 20, Senator Sonny Angara also signed.
Aftermath
Approximately 800,000 schoolchildren received the Dengvaxia vaccine and benefit from the protection it grants against dengue fever. However around 10% of those 800,000 had not had dengue fever before and therefore are at risk of severe infection because of the vaccine.
In the Philippines, the Dengvaxia controversy has contributed to overall vaccine hesitancy because of heightened concerns about vaccine safety. While concerns about vaccine safety are usually irrational, in the case of Dengvaxia there was a basis in evidence. Many parents of children who died blamed the vaccine.
Most of the deaths were caused by internal bleeding in the heart, lungs and brain, which are symptoms of hemorrhagic dengue.
According to the DOH, 729,105 grade 4 students from selected regions have received the first dose of the vaccine. Of these, 534,303 students had approved parental consent but only 491,990 students received the first dose of the vaccine.
Effects on COVID-19 vaccination program
A study published by the University of the Philippines College of Medicine directly attributes the Dengvaxia controversy as one of the major factors for the vaccine hesitancy of Filipinos affecting the COVID-19 vaccination program.
Reactions
Citizens, as well as Senator Ejercito, expressed frustration on February 5, 2018, blaming the PAO for panic in dengue vaccination. Attorney Persida Acosta of the PAO said that the PAO should not be blamed for that panic but Sanofi Pasteur itself.
Allegations of corruption
Employees of the Public Attorneys Office have asked the Office of the Ombudsman to issue a preventive suspension order against PAO chief Persida Acosta and her forensics chief Dr. Erwin Erfe for alleged corruption in the agency. It was alleged that Acosta has two "loyal" certified public accountants named Lira Hosea Suangco and Maveric Sales who are tasked to maintain office supplies such as bond paper to be used for the Dengvaxia cases. The funds, however, were used for other purposes. It was also alleged that Acosta and Erfe are using PAO funds to purchase tarpaulins, t-shirts, and coffins to be used in rallies.
In January 2021, the Ombudsman cleared Acosta and Erfe of criminal and administrative charges relating to the Dengvaxia issue, saying there was "no probable cause for malversation of public funds or property and illegal use of public funds or property."
See also
2019 Philippines measles outbreak – attributed to the aftermath of the controversy
References
Vaccine controversies
2017 in the Philippines
2018 in the Philippines
2017 controversies
2018 controversies
Health disasters in the Philippines
2018 health disasters | Dengvaxia controversy | [
"Chemistry",
"Biology"
] | 2,255 | [
"Vaccination",
"Drug safety",
"Vaccine controversies"
] |
55,964,039 | https://en.wikipedia.org/wiki/NGC%204252 | NGC 4252 is a spiral galaxy approximately 56 million light-years away from Earth in the constellation of Virgo. It belongs to the Virgo cluster of galaxies.
It was discovered by German astronomer Albert Marth on May 26, 1864.
See also
List of NGC objects (4001–5000)
References
External links
SEDS
Spiral galaxies
Virgo (constellation)
4252
39537
Astronomical objects discovered in 1864
Discoveries by Albert Marth
Virgo Cluster
07343 | NGC 4252 | [
"Astronomy"
] | 94 | [
"Virgo (constellation)",
"Constellations"
] |
55,964,224 | https://en.wikipedia.org/wiki/Alspach%27s%20conjecture | Alspach's conjecture is a mathematical theorem that characterizes the disjoint cycle covers of complete graphs with prescribed cycle lengths. It is named after Brian Alspach, who posed it as a research problem in 1981. A proof was published by .
Formulation
In this context, a disjoint cycle cover is a set of simple cycles, no two of which use the same edge, that include all of the edges of a graph. For a disjoint cycle cover to exist, it is necessary for every vertex to have even degree, because the degree of each vertex is two times the number of cycles that include that vertex, an even number. And for the cycles in a disjoint cycle cover to have a given collection of lengths,
it is also necessary for the sum of the given cycle lengths to equal the total number of edges in the given graph. Alspach conjectured that, for complete graphs, these two necessary conditions are also sufficient: if is odd (so that the degrees are even) and a given list of cycle lengths (all at most ) adds to (the number of edges in the complete graph) then the complete graph can always be decomposed into cycles of the given length. It is this statement that Bryant, Horsley, and Pettersson proved.
Generalization to even numbers of vertices
For complete graphs whose number of vertices is even, Alspach conjectured that it is always possible to decompose the graph into a perfect matching and a collection of cycles of prescribed lengths summing to . In this case the matching eliminates the odd degree at each vertex, leaving a subgraph of even degree, and the remaining condition is again that the sum of the cycle lengths equals the number of edges to be covered. This variant of the conjecture was also proven by Bryant, Horsley, and Pettersson.
Related problems
The Oberwolfach problem on decompositions of complete graphs into copies of a given 2-regular graph is related, but neither is a special case of the other.
If is a 2-regular graph with vertices, formed from a disjoint union of cycles of certain lengths, then a solution to the Oberwolfach problem for would also provide a decomposition of the complete graph into copies of each of the cycles of . However, not every decomposition of into this many cycles of each size can be grouped into disjoint cycles that form copies of , and on the other hand not every instance of Alspach's conjecture involves sets of cycles that have copies of each cycle.
References
Theorems in graph theory
Conjectures that have been proved | Alspach's conjecture | [
"Mathematics"
] | 538 | [
"Mathematical theorems",
"Theorems in discrete mathematics",
"Conjectures that have been proved",
"Mathematical problems",
"Theorems in graph theory"
] |
55,964,386 | https://en.wikipedia.org/wiki/NGC%20510 | NGC 510 is a double star in the constellation of Pisces. The stars are separated 8", and located 7' ESE of NGC 499 and 9' WNW of NGC 515.
The RNGC mislabels PGC 5102 as NGC 510.
Observational history
NGC 510 was discovered by Swedish astronomer Herman Schultz on November 11, 1867. The object was initially considered a "misty" object (a galaxy) based on the observations with research instruments of that time, and was included on the NGC list. Later it became clear that it was a double star.
See also
Double star
List of NGC objects (1–1000)
Pisces (constellation)
References
External links
SEDS
Double stars
Pisces (constellation)
510
Astronomical objects discovered in 1867
Discoveries by Herman Schultz (astronomer) | NGC 510 | [
"Astronomy"
] | 165 | [
"Pisces (constellation)",
"Constellations"
] |
55,964,410 | https://en.wikipedia.org/wiki/Carboxydothermus | Carboxydothermus is a genus of thermophilic, anaerobic bacteria from the family of Thermoanaerobacteraceae.
Phylogeny
The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI).
See also
List of bacteria genera
List of bacterial orders
References
Further reading
Thermoanaerobacterales
Bacteria genera
Thermophiles
Anaerobes | Carboxydothermus | [
"Biology"
] | 105 | [
"Bacteria",
"Anaerobes"
] |
55,965,344 | https://en.wikipedia.org/wiki/Spin%20Nernst%20Effect | The spin Nernst effect is a phenomenon of spin current generation caused by the thermal flow of electrons or magnons in condensed matter. Under a thermal drive such as temperature gradient or chemical potential gradient, spin-up and spin-down carriers can flow perpendicularly to the thermal current and towards opposite directions without the application of a magnetic field. This effect is similar to the spin Hall effect, where a pure spin current is induced by an electrical current. The spin Nernst effect can be detected by the spatial separation of opposite spin species, typically in the form of spin polarization (imbalanced spin accumulation) on the transverse boundaries of a material.
The spin Nernst effect of electrons was first experimentally observed in 2016 and published by two independent groups in 2017.
The spin Nernst effect of magnons (quanta of spin wave excitations) was theoretically proposed in 2016 in collinear antiferromagnetic materials, but its experimental confirmation remains elusive. In 2017, around the same time when its electronic counterpart was experimentally observed, the spin Nernst effect of magnons was first claimed in transition metal trichalcogenide MnPS3. However, the experiment involved ambiguities that cannot convincingly verify the spin Nernst effect of magnons, awaiting further experimental studies. With a more accurate description accounting for real device geometry, it was believed that optical detection should be more reliable than electronic detection. At present, optical detection of the spin Nernst effect of magnons has not been reported.
See also
Spin Hall effect
Nernst effect
References
Condensed matter physics
Spintronics
Walther Nernst | Spin Nernst Effect | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 338 | [
"Spintronics",
"Phases of matter",
"Materials science",
"Condensed matter physics",
"Matter"
] |
55,966,819 | https://en.wikipedia.org/wiki/Journal%20of%20Thermal%20Stresses | The Journal of Thermal Stresses is a monthly peer-reviewed scientific journal covering the theoretical and industrial applications of thermal stresses. It is published by Taylor & Francis. The journal was established in 1978 with Richard B. Hetnarski (Rochester Institute of Technology) as founding editor-in-chief. In July 2018 he was succeeded by Martin Ostoja-Starzewski (University of Illinois at Urbana-Champaign).
Abstracting and indexing
The journal is abstracted and indexed in:
CSA databases
Current Contents/Engineering, Computing, & Technology
Science Citation Index
According to the Journal Citation Reports, the journal has a 2020 impact factor of 3.28.
References
External links
Print:
Online:
Materials science journals
Monthly journals
English-language journals
Taylor & Francis academic journals
Academic journals established in 1978 | Journal of Thermal Stresses | [
"Materials_science",
"Engineering"
] | 158 | [
"Materials science stubs",
"Materials science journals",
"Materials science journal stubs",
"Materials science"
] |
55,967,394 | https://en.wikipedia.org/wiki/Glowing%20pickle%20demonstration | Applying line voltage across a pickled cucumber causes it to glow. A moist pickle contains salt as a result of the pickling process, which allows it to conduct electricity. Sodium (or other) ions within the pickle emit light as a result of atomic electron transitions, although it is not clear why the luminescence occurs at one end of the pickle.
The glowing pickle is used to demonstrate ionic conduction and atomic emission in chemistry classes, and also as a demonstration in lighting classes.
The first known fully documented demonstration was in a 1989 report from Digital Equipment Corporation. Although this was published as a full technical note and written up as a scientific paper, the publication date, April Fools' Day of that year, gives some indication as to the light-hearted nature of the document.
References
Chemistry classroom experiments
Electron states
Light sources | Glowing pickle demonstration | [
"Chemistry"
] | 174 | [
"Electron",
"Electron states",
"Chemistry classroom experiments"
] |
51,517,977 | https://en.wikipedia.org/wiki/NGC%20191 | NGC 191 is a spiral galaxy located in the constellation Cetus. It was discovered on November 28, 1785, by William Herschel.
NGC 191 is currently interacting with IC 1563. For that reason it was included in Halton Arp's Atlas of Peculiar Galaxies, under the section "Elliptical galaxies close to and perturbing spiral galaxies."
References
External links
Cetus
127
002331
0191
Intermediate spiral galaxies
Interacting galaxies | NGC 191 | [
"Astronomy"
] | 90 | [
"Cetus",
"Constellations"
] |
51,518,046 | https://en.wikipedia.org/wiki/NGC%20192 | NGC 192 is a spiral galaxy in the constellation Cetus. It was discovered on December 28, 1790 by William Herschel.
References
External links
0192
0401
002352
Barred spiral galaxies
Cetus
+00-02-104 | NGC 192 | [
"Astronomy"
] | 49 | [
"Cetus",
"Constellations"
] |
51,518,160 | https://en.wikipedia.org/wiki/Brian%20Robinson%20%28chemist%29 | Brian Harford Robinson (24 April 1940 – 30 August 2016) was a New Zealand inorganic chemist. He is noted for his contribution to cluster chemistry and the design of organometallic compounds with biomedical applications.
Early life and education
Born in Christchurch on 24 April 1940, Robinson was the son of Jack Robinson and Lurline Robinson (née Cross). He was educated at Christchurch Boys' High School, and then studied at the University of Canterbury, graduating Master of Science with second-class honours in chemistry in 1962. He completed a PhD at the same institution in 1964. His thesis, titled Studies in the coordination chemistry of certain transition metals, elucidated the first structure of a cluster compound and its unusual delocalised bonding.
On 12 May 1962, Robinson married Judith Rae, and they went on to have four children.
Academic and research career
After periods of post-doctoral research at the University of Newcastle upon Tyne and the University of Manchester in 1965 and 1966, Robinson was a faculty member in the Department of Chemistry at the University of Otago in Dunedin from 1967 to 2006. He became a professor in 1985 and the Mellor Professor of Chemistry in 1996, and served as the head of the Department of Chemistry from 1986 to 1998. When he retired in 2006 he was made a professor emeritus.
Building on his doctoral research, Robinson proposed that metal carbonyl clusters could participate in electron transfer reactions, and demonstrated that clusters are able to be reversibly reduced. Other research areas that he pursued included the design of organometallic compounds for use in biomedical research, and the development of molecular switches.
Later life and death
Following his retirement, Robinson continued to be an active researcher, including work to develop a post-surgical protective gel based on chitosan from squid. The resulting product was sold to American medical technology company Medtronic in 2012. In 2013, Robinson became chair of the board of the Dunedin branch of the University of the Third Age.
Robinson died in Wellington on 30 August 2016.
Honours and awards
In 1999 Robinson was elected a Fellow of the Royal Society of New Zealand. In 2010 he was awarded a Marsden Medal by the New Zealand Association of Scientists, in recognition of his lifetime contribution to science. He was also a Fellow of the New Zealand Institute of Chemistry, and the Society of Perfumers and Flavourists.
An active Rotarian, Robinson was a recipient of the Paul Harris Fellowship for community service in 2004.
References
1940 births
2016 deaths
Scientists from Christchurch
People educated at Christchurch Boys' High School
University of Canterbury alumni
New Zealand chemists
Inorganic chemists
Academic staff of the University of Otago
Fellows of the Royal Society of New Zealand
Fellows of the New Zealand Institute of Chemistry | Brian Robinson (chemist) | [
"Chemistry"
] | 540 | [
"Inorganic chemists"
] |
51,518,429 | https://en.wikipedia.org/wiki/NGC%20193 | NGC 193 is a lenticular galaxy located in the constellation Pisces. It was discovered on December 21, 1786, by William Herschel.
References
External links
0193
0408
+00-02-103
Pisces (constellation)
Lenticular galaxies
002359
Radio galaxies | NGC 193 | [
"Astronomy"
] | 60 | [
"Pisces (constellation)",
"Constellations"
] |
51,518,431 | https://en.wikipedia.org/wiki/Ramin%20Mazaheri | Ramin Mazaheri (; born 21 April 1983) is an Iranian audio engineer, music producer, and musician.
He has been cooperating, as an engineer, in the production of several significant albums, such as Aah-Baran (Mohammad-Reza Shajarian), Pieces from Iranian Composers (Tehran Symphonic Orchestra) Mian-e Khorshid Haye Hamisheh (Rastak Ensemble), To Life (Minus1), Rebel (Kourosh Yaghmaei); and some popular TV series, including Mokhtarnameh, Shahrzad, Mehmooni 1 & 2 and Shookhi Kardam; He also has produced several tracks for some Iranian singers such as Mazyar Fallahi and Ehsan Haghshenas.
Career
His career as an engineer started with accepting orders at his home studio in 2001, which he developed gradually. It was after he met Raymond Movsessian, a Professional audio engineer, who guided Ramin on professional levels, that he managed to establish Baran Studio in 2005.
In 2005, he was more productive in recording successful music Albums, In the same year he accepted to work with Raymond Movsessian, as an engineer assistant, at Mohammad Reza Shajarian Concert; He also recorded Naghsh e Khial, an Album by Ali Ghamsarai with Homayoon Shajarian as a vocalist; At the same time he was cooperating with some musicians like Mehdi Moghadam, Nariman, Amir yal Arjomand, Mani Rahnama, etc.
Baran Studio was transferred to a bigger place in 2010. Around this time Ramin cooperated with Mehran Modiri at Shookhi Kardam Series.
He recorded an album alongside Mehdi Paknejad (Setar Player) and Farhad Asadi (Tombak player) in 2011, which was released without any editing or mixing, so they decided to call it "Senavazi" ("Trio"). Shortly after that, they performed these pieces in Roudaki Hall. This was the first time that a sound engineer attended on the stage alongside the instrumentalists and microphones placement and soundcheck in front of the live studio audience.
He has worked in his career with many well-known artists and musicians such as Mohammad-Reza Shajarian, Kayhan Kalhor, Alexander Rahbari, The Kamkars, Shahram Nazeri, Behrouz Gharibpour, Mehdi Bagheri, Salar Aghili, Keyvan Kianian, Homayoun Shajarian, Kaveh Sarvarian, Hamzeh Yeganeh, Ali Shokat, Rastak Ensemble, Minus 1, Mohsen Namjoo, Hamed Behdad, Mehran Modiri, Ajam (band), Aref (singer), Reza Yazdani (singer), Mehdi Moghadam, Mazyar Fallahi, Amir Tavassoli, Farzin Gharahgozloo, Mohammad Reza Jadidi, Mohammad Esfahani, Alireza Assar, Payam Shams, Behrouz Saffarian, Masoud Fayyaz Zadeh, Milad Bagheri, etc.
Reza Abedyan, kamancheh player, in his interview with Melody Magazine, has said: "I felt so much happiness when I heard that for the first time a sound engineer attended on the stage alongside instrumentalists. Because it seems to me that this career always has been ignored by people".
Siamak Gholizadeh, in Etemad News has said: "Of course, the interesting and brilliant mix of Ramin Mazaheri cannot be ignored. The combination of electronic and rock music has rarely happened in Iran before, and this is the band (Baadzang) trump card in creating a new sound."
In 2017 he performed in 32nd Fajr International Music Festival, Research Section, on the "Sound, Recording and Accessories" topic. Also, "Kahgel" the album by Hamzeh Yeganeh, with his mixing and mastering, won the Barbad Award for the best Fusion album at that Festival.
In 2019 he was Judge (Jury) on Naser Farhoudi Award.
He produced video series as known as "The Sound of Music by Ramin Mazaheri" about how to record Iranian instruments.
Teaching and New Ventures
From 2016 to 2023, Ramin Mazaheri taught sound engineering and mixing at several universities in Iran, sharing his extensive knowledge and experience with the next generation of audio professionals.
In 2023, he founded Baran Sound Lab Inc. in Toronto, Canada, expanding his influence and expertise into the international arena. Baran Sound Lab Inc. focuses on innovative audio engineering solutions and music production, continuing the legacy of excellence established by Baran Studio in Iran.
Discography
As engineer (music)
As engineer (soundtrack - score)
As producer
References
External links
وب سایت رسمی رامین مظاهری
1983 births
Living people
Audio engineers
21st-century Iranian musicians
Iranian record producers | Ramin Mazaheri | [
"Engineering"
] | 1,071 | [
"Audio engineering",
"Audio engineers"
] |
51,518,452 | https://en.wikipedia.org/wiki/NGC%20194 | NGC 194 is an elliptical galaxy located in the constellation Pisces. It was discovered on December 25, 1790 by William Herschel.
References
External links
0194
0407
+00-02-105
Elliptical galaxies
Pisces (constellation)
002362 | NGC 194 | [
"Astronomy"
] | 56 | [
"Pisces (constellation)",
"Constellations"
] |
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