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78,630,061 | https://en.wikipedia.org/wiki/BO%20Lyncis | BO Lyncis, abbreviated BO Lyn and otherwise referred to as GSC 02985-01044, is a white-hued binary star in the northern constellation of Lynx. With an apparent magnitude of 11.49, it is too faint to be seen by the naked eye but can be observed using a telescope with an aperture of or larger. It is located at a distance of according to Gaia EDR3 parallax measurements, and is receding farther away from the Sun at a heliocentric radial velocity of 23.48 km/s.
It was first discovered to be a Delta Scuti variable in 1994 during a survey of blue horizontal branch stars, and was subsequently assigned its variable-star designation in 1997.
Stellar properties
The primary star is an A-type main-sequence star between the spectral types A5V and A8V, with a mass of approximately 1.76 and a luminosity fluctuating between 9.4 and 13.6 . A detailed spectral type of kA6hA5mA9 indicates that the classification would be A6 based on calcium K-lines, A5 based on hydrogen lines, and A9 based on the spectral lines of other metals.
It has been described as a high-amplitude Delta Scuti variable (HADS), also known as an AI Velorum star, with a period of 0.0933584 days (10.7114 cycles/day) and an amplitude of 0.23 mag. The relatively short period signals that the star has a low metallicity of around −0.3, meaning it has only 10−0.3 ≈ 50% as much iron content as the Sun. In 2005, the period was found to be steadily decreasing at a rate of −1.5 days/day (), which would later be revised to by Li et al. (2018). Concurrently, two additional possible pulsation frequencies were discovered, at 15.81 and 13.60 cycles/day.
The secondary star has a minimum mass of , which, coupled with the binary's blue color, suggests that it is an A- or F-type main-sequence star or a dim degenerate star. If the former is true, its luminosity is non-negligible, decreasing the apparent amplitude of the pulsating star (which happens to be relatively small for a HADS). Assuming an amplitude typical of the primary's spectral type at 0.40 mag, the luminosity of the secondary can be derived at ~8.4 , corresponding to a 1.67 late A-type main-sequence star. This places the inclination of the system at about 42°.
Stellar kinematics measurements imply that the star belongs to the old disk population of the Milky Way, though its distance above the Galactic plane is , which is two scale heights of the old disk population.
References
A-type main-sequence stars
Delta Scuti variables
Binary stars
Lynx (constellation)
J08430121+4059517
Lyncis, BO | BO Lyncis | [
"Astronomy"
] | 626 | [
"Lynx (constellation)",
"Constellations"
] |
78,630,383 | https://en.wikipedia.org/wiki/1%2C1-Dimethylurea | 1,1-Dimethylurea (DMU) is a urea derivative used as a polar solvent and a reagent in organic reactions. It is a solid, but forms a eutectic with a low melting point in combination with various hydroxylic additives that can serve as a environmentally sustainable solvent for various chemical reactions. The unsubstituted nitrogen, as an amine-like region, can serve as a nucleophile for a wide range of reactions, including reaction with acyl halides to form acylureas, coupling with vinyl halides, and multi-component condensation reaction with aldehydes. The unsubstituted amide-like portion can undergo oxidative coupling with alkenes to give dihydrooxazoles.
References
Ureas
Methyl compounds
Amide solvents | 1,1-Dimethylurea | [
"Chemistry"
] | 175 | [
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs",
"Ureas"
] |
78,630,467 | https://en.wikipedia.org/wiki/Antonio%20Pizzi | Antonio Pizzi (born in 1946) is an Italian-born, French-South African polymer and materials chemist and professor emeritus of industrial chemistry at the University of Lorraine, who is an expert in the fields of bioadhesives, bioresins and wood adhesives and an elected fellow (FIAWS) of the International Academy of Wood Science.
Career
Pizzi holds multiple advanced degrees, including a doctorate in chemistry (D.Chem.) from the University of Rome (1970), as well as a Ph.D. in organic chemistry and a D.Sc. degree in wood chemistry, both from universities of South Africa. His early career combined academic roles with industry experience, which provided a foundation for his novel research contributions.
From 1989 to 1995, he served as a professor of polymer chemistry at the University of the Witwatersrand in Johannesburg, where he also held the position of head of the Department of Chemistry from 1991 to 1993. In 1994, he returned to Europe to join the University of Lorraine in France, specifically the Laboratory of Study and Research on Wood Materials (LERMAB-ENSTIB).
Pizzi's research primarily focuses on polycondensation resins, particularly biosourced and synthetic wood adhesives. He is widely acknowledged for advancing the development and application of adhesives derived from renewable materials, as well as the composites bonded with them.
International recognition
Throughout his career, Pizzi has published extensively, authoring more than 1,000 research articles, patents, and over 12 books, including foundational works on bioadhesives and bioresins. His contributions have earned numerous international scientific awards, reflecting his influence on the field of industrial and polymer chemistry. Pizzi's work is particularly related to the areas of renewable resources and environmentally-friendly adhesive technologies.
His research work is well recognised in the fields of materials science and wood science and technology, having almost 30,000 citations at Scopus, and more than 47,000 citations at Google Scholar with an h-index of 99.
In October 2023, a referenced meta-research conducted by John Ioannidis and his team at Stanford University included Antonio Pizzi in Elsevier Data 2022, where he was ranked at the global top 2% of researchers of all time in the area of materials, having a superior composite index of 4.0955.
In addition, Pizzi has won the prestigious Schweighofer Wood Innovation award (2006), and also twice the Descartes Research Prize, awarded by the European Commission.
Books
Handbook of Adhesive Technology (2017), CRC Press
Lignocellulosic Fibers and Wood Handbook (2016), Wiley
Wood Adhesives (2010), CRC Press
Advanced Wood Adhesives Technology (1994), CRC Press
References
External links
Scopus
Google Scholar
CV of Antonio Pizzi (pg. 140)
Lermab
Italian scientists
French scientists
Fellows of the International Academy of Wood Science
Wood scientists
1946 births
Living people | Antonio Pizzi | [
"Materials_science"
] | 611 | [
"Wood sciences",
"Wood scientists"
] |
78,631,349 | https://en.wikipedia.org/wiki/5-Methylchrysene | 5-Methylchrysene is a polycyclic aromatic hydrocarbon (PAH) with a molecular weight of 242.3 g/mol and melting point of 117.5 °C (243.5°F). The chemical formula of it is C19H14. It has a vapour pressure of 0.00000025 mmHg. It can cause cancer according to an independent committee of scientific and health experts (California Office of Environmental Health Hazard Assessment (OEHHA)). It appears as purple crystals and it is water insoluble (0.062 mg/L at 27 °C)(80.6°F)but soluble in acetone. It is a carbopolycyclic compound.
5-Methylchrysene is a member of a group of chemicals called polycyclic aromatic hydrocarbons (PAHs). 5-Methylchrysene is a product of incomplete combustion and as a component of tobacco and marijuana smoke, which will result in its direct release to the natural environment. There is no commercial production of this compound. 5-Methylchrysene is formed during the incomplete burning of coal, oil, gas, wood, garbage, or other organic substances. PAHs generally occur as complex mixtures, for example as part of combustion products such as soot, not as single compounds. PAHs occur naturally in volcanoes and forest fires. They can also be found in substances such as crude oil and coal. They are found throughout the environment in the air, water, and soil.
It is a solid that exhibits a brilliant bluish-violet fluorescence in ultraviolet (= UV) light. When heated to decomposition it emits acrid smoke & irritating fumes. According to the MeSH Pharmacological Classification it is a carcinogen.
It has an OSHA Permissible Exposure Limit (=PEL)over an 8 hours Time Weighted Average (= TWA) of 0.2 mg/m3. This is also the Threshold Limit Values (TLV).
NIOSH recommends recommends an 10 Hours Time-Weighted Average (= TWA) Exposure Limit (= EL) of 0.1 mg/m3. NIOSH considers coal tar pitch volatiles to be potential occupational carcinogens. NIOSH usually recommends that occupational exposures to carcinogens be limited to the lowest feasible concentration.
Indoor air particulate samples (<10 um) were collected in Chinese homes from Xuan Wei county burning smokey coal, smokeless coal, and wood in 1983 and 1984; the concentration of 5-methylchrysene was 1.6 to 17 ug/m3, 0.21 to 3.5 ug/m3, and 0.03 to 0.05 ug/m3, respectively. Sampling was conducted in March and September, 2011.
5-Methylchrysene was detected outdoors at 21 and 13 pg/m3 in PM2.5 samples within 10 m of an 8-lane highway in Raleigh, NC, with an annual average daily traffic count of 125,000 vehicles and a parallel secondary road of 200 vehicles/day 275 m distant from the highway collection site, respectively.
Concentrations in mainstream smoke of US domestic brand cigarettes at a range of 2.5-3.9 ng/cigarette; limit of detection in smoke = 0.94 pg.
Dust/air mixture may ignite and explode. Vigorous reactions, sometimes amounting to explosions, can result from the contact between aromatic hydrocarbons, such as 5-METHYLCHRYSENE, and strong oxidizing agents. They can react exothermically with bases and with diazo compounds. Substitution at the benzene nucleus occurs by halogenation (acid catalyst), nitration, sulfonation, and the Friedel-Crafts reaction.
There is sufficient evidence in experimental animals for the carcinogenicity of 5-methylchrysene. 5-Methylchrysene is also possibly carcinogenic to humans (IARC Group 2B).
Associated disorders and diseases are adenoma, carcinoma, sarcoma, liver- and ling-neoplasms.
References
Carcinogens
Polycyclic aromatic hydrocarbons | 5-Methylchrysene | [
"Chemistry",
"Environmental_science"
] | 857 | [
"Carcinogens",
"Toxicology"
] |
75,630,144 | https://en.wikipedia.org/wiki/Tris%282%2C4%2C6-trimethoxyphenyl%29phosphine | Tris(2,4,6-trimethoxyphenyl)phosphine (TTMPP) is a large triaryl organophosphine whose strong Lewis-basic properties make it useful as an organocatalyst for several types of chemical reactions.
Reactions
TTMPP removes the trimethylsilyl group from ketene silyl acetals (the enol ether of esters) to give enolates that can then act as strong nucleophiles. It thus serves as a catalyst for Mukaiyama aldol reactions and group-transfer chain-growth polymerization reactions.
As a Brønsted base, TTMPP can deprotonate various alcohols, giving nucleophilic alkoxides that can undergo Michael addition reactions.
TTMPP can act as a Michael nucleophile itself to catalyze Baylis–Hillman reactions.
Uses
TTMPP is used as a ligand to form palladium-phosphine catalysts which are more reactive than triphenylphosphine-based catalysts.
References
Tertiary phosphines
Catalysts
Methoxy compounds
Phenyl compounds | Tris(2,4,6-trimethoxyphenyl)phosphine | [
"Chemistry"
] | 244 | [
"Catalysis",
"Catalysts",
"Chemical kinetics"
] |
75,630,534 | https://en.wikipedia.org/wiki/Konstantin%20Mitenev | Konstantin Vitalyevich Mitenev (born May 18, 1956) is a Russian artist, filmmaker, film actor, author.
Biography
In 1984, Mitenev joined the film studio Mzhalalafilm.
As an artist, Konstantin Mitenev was actively involved in Leningrad's underground art scene in the 1980s.
Mitenev began to engage in new media art after the international video festival "OSTranenie" at the Bauhaus, Dessau, in 1993.
Since the early 90s, he took part in the net art movement.
In 1996, he created the artistic projects UnDiNa (United Digital Nations) and Xyman (constructor of the body) with Alla Mitrofanova. In the same year, Konstantin Mitenev organized with Alla Mitrofanova the first Russian cyber-expedition NETMAN. He created the first network TV in Russia called Twins TV in 1997. Mitenev opened the first online art gallery in Russia, BioNet. He published a manifesto — Next Media.
At the suggestion of Geert Lovink, Konstantin Mitenev has organized A Great Clone Party, the world's first sound stream via the Internet between St. Petersburg and nine cities (Linz — Paris — Berlin — Geneva — Lausanne — St. Petersburg — Kobe — San Francisco). He called his computer Masha Pentium as a co-author (from now he signs as Kostya Mitenev & Masha Pentium - k@m).
Konstantin Mitenev met Bruce Sterling in St. Petersburg in late 90s. Later Mitenev became a character in his book Zeitgeist (necrorealist Viktor Bilibin). At the same time Konstantin Mitienev corresponded with curator Inke Arns.
In 2015, he held an art picket at the 56th Venice Biennale with an art picket Separation of Art From the State.
In 2022, he went to Venice for a collective exhibition with his thesis "Do Art, Not War". In the same year, Mitenev participated in an anti-war exhibition in Geneva. Also Mitenev took part in international media art festival CYFEST-14.
Konstantin Mitenev lives and works in Lausanne, Switzerland.
Konstantin Mitenev's works are in the collection of Kuryokhin Center, St. Petersburg, in the archives of CYLAND Media Art Lab.
References
External links
Konstantin Mitenev on Russian Art Archive Network: https://russianartarchive.net/en/catalogue/person/PBARF
Konstantin Mitenev on CYLAND Video archive: https://videoarchive.cyland.org/video_artists/mitenev-kostya/
1956 births
20th-century Russian artists
21st-century Russian artists
21st-century Russian male actors
Living people
Net.artists
Russian filmmakers | Konstantin Mitenev | [
"Technology"
] | 579 | [
"Multimedia",
"Net.artists"
] |
75,631,185 | https://en.wikipedia.org/wiki/Tremella%20versicolor | Tremella versicolor is a species of fungus in the family Tremellaceae. It produces small, pustular, gelatinous basidiocarps (fruit bodies) and is parasitic on the basidiocarps of Peniophora species, a genus of corticioid fungi, on dead attached or recently fallen branches. It was originally described from England.
Taxonomy
Tremella versicolor was first published in 1854 by British mycologists Miles Joseph Berkeley & Christopher Edmund Broome based on several collections from England on basidiocarps of Peniophora nuda on deciduous trees.
Description
Fruit bodies are gelatinous, orange-red to brownish red, initially up to 2.5 mm across, and discoid to pustular. Eventually they coalesce and become effused cerebriform (brain-like), up to 50 mm across. Microscopically, the hyphae have clamp connections and the basidia are tremelloid (ellipsoid, with oblique to vertical septa), 2 to 4-celled, 14 to 30 by 8 to 11 μm. Sterigmata and basidiospores are not formed in the initial, discoid to pustular stage; instead, clusters of small, ellipsoid conidiospores are released, typically with a thin wisp of ribbon-like hypha still attached. In the effused, cerebriform stage, smooth, globose to subglobose basidiospores are produced measuring 5.5 to 8 by 7.5 to 10 μm.
Similar species
Gelatinous fruit bodies of Hormomyces peniophorae are of similar size and shape and were described on basidiocarps of Peniophora lycii in England, but can be distinguished microscopically by having hyphae that lack clamp connections and no known teleomorph (basidia-bearing) state. Tremella versicolor was formerly confused with Tremella subencephala, but this forms fruit bodies on basidiocarps of the corticioid fungus Acanthophysium lividocoeruleum.
Habitat and distribution
Tremella versicolor is a parasite on basidiocarps of the lignicolous, corticioid genus Peniophora, including Peniophora lycii, P. cinerea, P. quercina, P. nuda, P. violaceolivida, P. reidii, and P. incarnata. The hosts typically grow on dead, attached or recently fallen branches of deciduous trees.
The species was originally described from England and has been recorded in Europe from Belgium, Denmark, Germany, Italy, the Netherlands, and Northern Ireland. Old reports from Sweden refer to Tremella subencephala. Tremella versicolor has also been reported from the USA.
References
versicolor
Fungi of Europe
Fungi of North America
Fungi described in 1854
Taxa named by Miles Joseph Berkeley
Parasitic fungi
Fungus species | Tremella versicolor | [
"Biology"
] | 654 | [
"Fungi",
"Fungus species"
] |
75,631,986 | https://en.wikipedia.org/wiki/Mathini%20Sellathurai | Mathini Sellathurai is an electrical engineer whose research topics include wireless communications, radar, cognitive radio, and multiple-input and multiple-output radio communications. Educated in Sri Lanka, Sweden and Canada, she has worked in Canada, the US, and Scotland, where she is professor in signal processing and dean of science and engineering at Heriot-Watt University.
Education and career
Sellathurai has a bachelor's degree in engineering from the University of Peradeniya in Sri Lanka. She earned a licenciate in signal processing and communications in 1997 from the KTH Royal Institute of Technology in Stockholm, Sweden, and completed a Ph.D. in 2001 from McMaster University in Hamilton, Ontario. Her doctoral dissertation was supervised by Simon Haykin and concerned the Bell Laboratories Layered Space-Time architecture for exploiting multi-path wireless communications; it won the 2002 Natural Sciences and Engineering Council Doctoral Prize. As a doctoral student, she also worked as a visiting researcher at Bell Labs in the US.
After postdoctoral research at the Communications Research Centre Canada from 2001 to 2004, she joined Heriot-Watt University in 2004.
Recognition
Sellathurai was named an IEEE Fellow, in the 2024 class of fellows, "for contributions to multi-user, multi-functional and multi-antenna wireless communications".
References
External links
Year of birth missing (living people)
Living people
Electrical engineers
Women electrical engineers
KTH Royal Institute of Technology alumni
McMaster University alumni
Academics of Heriot-Watt University
Fellows of the IEEE | Mathini Sellathurai | [
"Engineering"
] | 306 | [
"Electrical engineering",
"Electrical engineers"
] |
75,632,051 | https://en.wikipedia.org/wiki/Neptunium%28III%29%20bromide | Neptunium(III) bromide is a bromide of neptunium, with the chemical formula of NpBr3.
Preparation
Neptunium(III) bromide can be prepared by reacting neptunium dioxide and aluminium bromide:
Properties
Neptunium(III) bromide is a green solid. It can crystallize in two crystal systems:
α-NpBr3 is hexagonal with lattice parameters a = 791.7 pm and c = 438.2 pm. It has the same structure as uranium trichloride.
β-NpBr3 is orthorhombic with lattice parameters a = 411 pm, b = 1265 pm and c = 915 pm. It has the same structure as the bromides from plutonium to californium.
Neptunium(III) bromide also has a green hexahydrate, which is monoclinic.
Reactions
At 425 °C, neptunium(III) bromide bromide can be further brominated by bromine to form neptunium(IV) bromide.
References
External reading
Neptunium(III) compounds
Bromides
Actinide halides | Neptunium(III) bromide | [
"Chemistry"
] | 250 | [
"Bromides",
"Salts"
] |
75,632,375 | https://en.wikipedia.org/wiki/Thorium%28IV%29%20bromide | Thorium(IV) bromide is an inorganic compound, with the chemical formula of ThBr4.
Preparation
Thorium(IV) bromide can be obtained by reacting thorium dioxide, bromine and carbon at 800~900 °C. This method produces a mixture of alpha and beta forms of thorium bromide. The pure α-form product is obtained by heating the mixture at 330~375 °C for a long time. The pure β form is obtained by heating the product to 470 °C and then rapidly cooling it in ice water.
Thorium(IV) bromide can also be produced by the reaction of thorium and bromine. Thorium hydroxide reacts with hydrobromic acid to crystallize hydrates from the solution.
Properties
Thorium(IV) bromide exists in low-temperature α-type and high-temperature β-type. They are both white deliquescent solids and are easily soluble in water, ethanol and ethyl acetate. It reacts with fluorine gas under standard conditions and with chlorine or oxygen when heated. The beta form of thorium bromide is metastable at room temperature and converts to the alpha form over 10 to 12 weeks, with the conversion from alpha to beta occurring at around 420 °C. The α-type thorium(IV) bromide is an orthorhombic crystal, while the β-type thorium(IV) bromide is a tetragonal crystal with space group I41/amd. Some of its hydrates are known, and these hydrates form thorium oxybromide on heating.
References
External reading
Thorium(IV) compounds
Bromides
Actinide halides | Thorium(IV) bromide | [
"Chemistry"
] | 342 | [
"Bromides",
"Salts"
] |
75,633,903 | https://en.wikipedia.org/wiki/Anna%20Moore | Anna Marie Moore is an astronomer who was instrumental in the formation of the Australian Space Agency as part of the expert reference group of the Australian Government. She was nominated as a fellow of the Australian Academy of Technological Sciences and Engineering in 2023 for her contributions to space exploration. She is Director of The Australian National University Institute for Space and the Advanced Instrumentation Technology Centre.
Education
Moore was awarded a BA from Cambridge University, 1994, a Masters of Space Sciences from The University of London, 1995 and PhD in astronomy from the University of Sydney, 2000.
Career
Moore was employed at the Arcetri Observatory from 2004 to 2005, California Institute of Technology, from 2005 to 2017, and the Australian National University from 2017 onwards. She has received funding from various sources including the National Science Foundation, for SGER: United States participation in the 2007 Traverse to Dome A- Optical Sky Brightness and Ground Layer Turbulence Profiling. Moore also has received funding from the NSF for Gattini-UV South Pole camera research and the Australian Research Council for research on the Kunlun Infrared Sky Survey.
Moore is director of InSpace, and established and led the Institute for Space at ANU. At InSpace Director, she has exceeded normal diversity benchmarks by cultivating a workforce that is 75% women in an industry that is traditionally occupied by men. Her initiatives have facilitated the inclusion of female researchers within the InSpace Mission Specialist team and Technical Advisory Groups, two bodies that influence Australia's overarching space strategy.
During her tenure as Director of the Advanced Instrumentation and Technology Centre (AITC) at ANU, she played a role broaden the scope of space testing services for the aerospace sector in both Australia and New Zealand. She also ensured access for the space community to the AITC's National Space Test Facility (NSTF).
By early 2020, during the COVID-induced closures affecting much of Australian business, Moore facilitated the reopening of NSTF's first facility at ANU to open. This action ensured the continual fulfillment of heightened space testing demands from space companies, start-ups, and universities across Australia.
Select publications
Moore has authored over 100 peer-reviewed publications, with over 3060 citations and an H index of 29 as of 2023. Moore has also written various articles on space for The Conversation, on 'Why space matters' and space exploration in a post-covid world.
P Morrissey, M Matuszewski, DC Martin, JD Neill, H Epps, J Fucik, et al. (2018). The keck cosmic web imager integral field spectrograph. The Astrophysical Journal 864 (1), 93. DOI 10.3847/1538-4357/aad597
DC Martin, D Chang, M Matuszewski, P Morrissey, S Rahman, A Moore, et al. (2014). Intergalactic medium emission observations with the Cosmic Web Imager. I. The circum-QSO medium of QSO 1549+ 19, and evidence for a filamentary gas inflow. The Astrophysical Journal 786 (2), 106
JE Larkin, AM Moore, SA Wright, JE Wincentsen, D Anderson, et al. (2016) The infrared imaging spectrograph (IRIS) for TMT: instrument overview. Ground-based and Airborne Instrumentation for Astronomy VI 9908, 582–594
Awards
2023 – Fellow of the Australian Academy of Technological Sciences and Engineering
2021 – Australian Space Awards
References
External links
TROVE
ATSE
Living people
Astronomers
Alumni of the University of Cambridge
Fellows of the Australian Academy of Technological Sciences and Engineering
Australian women academics
Women in space
Australian women scientists
Year of birth missing (living people)
University of Sydney alumni | Anna Moore | [
"Astronomy"
] | 764 | [
"Astronomers",
"People associated with astronomy"
] |
75,634,850 | https://en.wikipedia.org/wiki/Amanita%20friabilis | Amanita gioiosa is a species of Amanita found across Europe. It grows amongst Alder.
References
External links
friabilis
Fungi of Europe
Fungus species | Amanita friabilis | [
"Biology"
] | 36 | [
"Fungi",
"Fungus species"
] |
75,634,875 | https://en.wikipedia.org/wiki/Amanita%20islandica | Amanita islandica is a species of Amanita found in Iceland growing among birch and spruce.
References
External links
islandica
Fungi of Europe
Fungi described in 1992
Fungus species | Amanita islandica | [
"Biology"
] | 37 | [
"Fungi",
"Fungus species"
] |
75,634,881 | https://en.wikipedia.org/wiki/Amanita%20silvicola | Amanita silvicola, also known as the woodland amanita or Kauffman's forest amanita, is a species of Amanita found in coniferous woods the Pacific Northwest and California.
A. silvicola is a small to medium-sized white mushroom, distinguishable from most other white Amanita species by its short stalk. Its cap ranges from 5–12 cm and is pure white, convex to flat, often with an incurved margin. The cap is initially rounded, covered in a "wooly" outer veil that later leaves soft patchy remnants across its surface as it flattens. The stem is patched with volva remains, and is slightly larger at its base. Gills are white, close and crowded, and free, just reaching the stem, or to narrowly adnate. The flesh of A. silvicola does not change colour when bruised or cut, but it's cap may discolour with age.
The edibibility of A. Silivicola is uncertain, but, due to its close resemblance to two poisonous mushrooms in the Amanita genus, A. pantherina and A. Smithiana, experimentation with this mushroom is strongly advised against.
Description
The cap of A. silvicola are 5 to 12 cm wide, dry and pure white in color. In advanced age and with decay, the cap may discolour, developing, as observed by Kauffman, "bright rose-colored spots and streaks". Younger fruiting bodies (mushrooms) are covered by a fluffy continuous universal veil, which breaks up irregularly across its slightly sticky surface into soft powdery patches instead of firm warts. The flesh of the cap thins considerably at its margin, which remains incurved into maturity. The gills are white and crowded together and have a free to narrowly adnate attachment, though sometimes reach towards the stipe in a deccurent tooth. The gills are medium broad, 6-7mm, with cottony edges, and in maturity they project below the margin of the cap. A. silvicola spores 8.0-10.0 μm by 4.2-6.0 μm, they are smooth, amyloid, ellipsoid and colourless, leaving a white spore print.
The stem is 50 to 120mm long,12 to 25mm thick and stout, tapering slightly as it reaches the cap. It sometimes has a slight ring on its cap. A. silvicola rarely roots, it has a basal marginate bulb (distinctly separate from the stem) at its base, about 3–4 cm thick with wooly veil remnants on its margin. The flesh of A. silvicola is white and does not change color when cut.
Habitat and distribution
Amanita silvicola is found in the Pacific northwest of North America, California, and more rarely in the Sierra Nevada mountains. The IUCN Red List has assessed it as Least Concern (LC), as the population is stable and "locally common" in the Pacific northwest and California.
A. silvicola is a terrestrial species, it can be found as a solitary mushroom or in small groups in coniferous woods, especially under Western Hemlock. It has a preference for areas of high rainfall.
Taxonomy and Etymology
The species was first described and named by Kauffman in 1925, who had collected the type specimen in Mt. Hood, Oregon on September 30, 1922. The species epithet silvicola is derived from silva, Latin for "wood" or "forest", and -cola, Latin suffix for "dweller of" or "inhabiting", referring to its habitat.
See also
:Category:Taxa named by Calvin Henry Kauffman
List of Amanita species
References
External links
silvicola
Fungus species | Amanita silvicola | [
"Biology"
] | 791 | [
"Fungi",
"Fungus species"
] |
75,634,884 | https://en.wikipedia.org/wiki/Non-normal%20modal%20logic | A non-normal modal logic is a variant of modal logic that deviates from the basic principles of normal modal logics.
Normal modal logics adhere to the distributivity axiom () and the necessitation principle which states that "a tautology must be necessarily true" ( entails ). On the other hand, non-normal modal logics do not always have such requirements. The minimal variant of non-normal modal logics is logic E, which contains the congruence rule in its Hilbert calculus or the E rule in its sequent calculus upon the corresponding proof systems for classical propositional logic. Additional axioms, namely axioms M, C and N, can be added to form stronger logic systems. With all three axioms added to logic E, a logic system equivalent to normal modal logic K is obtained.
Whilst Kripke semantics is the most common formal semantics for normal modal logics (e.g., logic K), non-normal modal logics are often interpreted with neighbourhood semantics.
Syntax
The syntax of non-normal modal logic systems resembles that of normal modal logics, which is founded upon propositional logic. An atomic statement is represented with propositional variables (e.g., ); logical connectives include negation (), conjunction (), disjunction () and implication (). The modalities are most commonly represented with the box () and the diamond ().
A formal grammar for this syntax can minimally be defined using only the negation, disjunction and box symbols. In such a language,
where is any propositional name. The conjunction may then be defined as equivalent to . For any modal formula , the formula is defined by . Alternatively, if the language is first defined with the diamond, then the box can be analogously defined by .
For any propositional name , the formulae and are considered propositional literals whilst and are considered modal literals.
Proof systems
Logic E, the minimal variant of non-normal modal logics, includes the RE congruence rule in its Hilbert calculus or the E rule in its sequent calculus.
Hilbert calculus
The Hilbert calculus for logic E is built upon the one for classical propositional logic with the congruence rule (RE): . Alternatively, the rule can be defined by . Logics containing this rule are called congruential.
Sequent calculus
The sequent calculus for logic E, another proof system that operates on sequents, consists of the inference rules for propositional logic and the E rule of inference: .
The sequent means entails , with being the antecedent (a conjunction of formulae as premises) and being the precedent (a disjunction of formulae as the conclusion).
Resolution calculus
The resolution calculus for non-normal modal logics introduces the concept of global and local modalities. The formula denotes the global modality of the modal formula , which means that holds true in all worlds in a neighbourhood model. For logic E, the resolution calculus consists of LRES, GRES, G2L, LERES and GERES rules.
The LRES rule resembles the resolution rule for classical propositional logic, where any propositional literals and are eliminated: .
The LERES rule states that if two propositional names and are equivalent, then and can be eliminated. The G2L rule states that any globally true formula is also locally true. The GRES and GERES inference rules, whilst variants of LRES and LERES, apply to formulae featuring the global modality.
Given any modal formula, the proving process with this resolution calculus is done by recursively renaming a complex modal formula as a propositional name and using the global modality to assert their equivalence.
Semantics
Whilst Kripke semantics is often applied as the semantics of normal modal logics, the semantics of non-normal modal logics are commonly defined with neighbourhood models. A standard neighbourhood model is defined with the triple where:
is a non-empty set of worlds.
is the neighbourhood function that maps any world to a set of worlds. The function denotes a power set.
is the valuation function which, given any propositional name , outputs a set of worlds where is true.
The semantics can be further generalised as bi-neighbourhood semantics.
Additional axioms
The classical cube of non-normal modal logic considers axioms M, C and N that can be added to logic E defined as follows.
A logic system containing axiom M is monotonic. With axioms M and C, the logic system is regular. Including all three axioms, the logic system is normal.
With these axioms, additional rules are included in their proof systems accordingly.
References
Modal logic
Semantics | Non-normal modal logic | [
"Mathematics"
] | 987 | [
"Mathematical logic",
"Modal logic"
] |
75,634,894 | https://en.wikipedia.org/wiki/Amanita%20diemii | Amanita diemii is a species of Amanita found growing under Nothofagus in Argentina and Chile.
References
External links
diemii
Fungi described in 1954
Fungus species | Amanita diemii | [
"Biology"
] | 39 | [
"Fungi",
"Fungus species"
] |
75,635,757 | https://en.wikipedia.org/wiki/Shang-Ping%20Xie | Shang-Ping Xie is a climatology and oceanography researcher who holds the Roger Revelle Chair at Scripps Institution of Oceanography. Known best for his research on interaction between the world's oceans and atmosphere and on El Niño–Southern Oscillation, Xie is noted as a Highly Cited Researcher by Clarivate.
Early life and education
Xie was born in Quzhou in 1963. He entered university after the Cultural Revolution had ended, and studied oceanography, though he had never seen the ocean before. His education includes:
Bachelor of Science, Shandong College of Oceanography (Ocean University of China), 1984
Study at Dalian College of Foreign Languages, 1984–85
Master of Science, Tohoku University, 1988
Doctor of Science, Tohoku University, 1991
He was a visiting scientist to Princeton University from 1991 to 1993, and a research associate for the University of Washington from 1993 to 1994.
Career
Xie had been employed at the University of Hawaiʻi as a professor of meteorology until he joined the Scripps Institution of Oceanography of the University of California, San Diego in 2012 as the inaugural Roger Revelle Chair, a title named for pioneering researcher Roger Revelle, established with an endowment from the Revelle family. While at Hawaiʻi, he was faculty in the International Pacific Research Center of the School of Ocean and Earth Science and Technology.
In April 2016, as a Scripps professor, Xie returned to the University of Washington as an endowed lecturer—he gave a lecture on El Niño in the Graduate Students' Distinguished Visiting Lecture series.
Research
In 2013, a study co-authored by Xie and published in Nature suggested that the slowdown in global warming was tied to cooling in parts of the Pacific Ocean. Further research into the slowdown was published in 2015, in the journal Nature Climate Change. Xie has also published research on modeling the role of human activity to global warming; a 2015 co-authored paper in Nature Geoscience modeled the evolution of global temperature, creating a new method of tracking anthropogenic global warming. The modelling was reported on again in 2016, when Xie and others modelled human activities' impact on warming. Other papers on climate change have included collaboration with authors affiliated with Duke University and University of Wisconsin–Madison. In 2019, Xie published research with scientists from the Lawrence Berkeley National Laboratory, where they modelled Hadley cells to predict changes in the monsoon season of parts of Asia. In a 2022 article published by the World Economic Forum and The Conversation and co-authored by Xie, the authors claim that tropical cyclones have been increasing in intensity over time.
In 2016, Xie was the organizer of a special issue of Advances in Atmospheric Sciences.
Xie has been included as a Highly Cited Researcher by Clarivate in the field of geosciences.
Awards
Sverdrup Gold Medal, conferred by the American Meteorological Society (2017)
Notes
References
External links
Profile at Scripps Institution of Oceanography
Living people
1963 births
Date of birth missing (living people)
Nationality missing
People from Quzhou
University of Hawaiʻi at Mānoa faculty
Scripps Institution of Oceanography faculty
Environmental scientists
Atmospheric scientists
Oceanographers | Shang-Ping Xie | [
"Environmental_science"
] | 650 | [
"Environmental scientists"
] |
75,637,218 | https://en.wikipedia.org/wiki/Ethylcholine%20mustard | Ethylcholine mustard is a neurotoxic nitrogen mustard that destroys cholinergic neurons. It's the hydrolysis product of the HN1 vesicant.
Mechanism of action
Under aqueous condition, ethylcholine mustard forms the highly reactive ethylcholine aziridinium (AF64A) ion. AF64A is transported into cholinergic neurons by the choline transporter. AF64A irreversibly inhibits the choline acetyltransferase and thereby inhibits acetylcholine synthesis. AF64A can also produce cytotoxic effects, leading to cell death.
The aziridinium ion can be isolated as picrylsulfonate salt.
See also
HN1 (nitrogen mustard)
References
Nitrogen mustards
Neurotoxins
Chloroethyl compounds
Ethanolamines | Ethylcholine mustard | [
"Chemistry"
] | 181 | [
"Neurochemistry",
"Neurotoxins"
] |
75,637,570 | https://en.wikipedia.org/wiki/Regret-free%20mechanism | In mechanism design, a regret-free truth-telling mechanism (RFTT, or regret-free mechanism for short) is a mechanism in which each player who reveals his true private information does not feel regret after seeing the mechanism outcome. A regret-free mechanism incentivizes agents who want to avoid regret to report their preferences truthfully.
Regret-freeness is a relaxation of truthfulness: every truthful mechanism is regret-free, but there are regret-free mechanisms that are not truthful. As a result, regret-free mechanisms exist even in settings in which strong impossibility results prevent the existence of truthful mechanisms.
Formal definition
There is a finite set X of potential outcomes. There is a set N of agents. Each agent i has a preference Pi over X.
A mechanism or rule is a function f that gets as input the agents' preferences P1,...,Pn, and returns as output an outcome from X.
The agents' preferences are their private information; therefore, each agent can either report his true preference, or report some false preference.
It is assumed that, once an agent observes the outcome of the mechanism, he feels regret if his report is a dominated strategy "in hindsight". That is: given all possible preferences of other agents, which are compatible with the observed outcome, there is an alternative report that would have given him the same or a better outcome.
A regret-free truth-telling mechanism is a mechanism in which an agent who reports his truthful preferences never feels regret.
In matching
Fernandez studies RFTT in two-sided matching. He shows that:
In a one-to-one matching market, the Gale–Shapley (GS) algorithm is RFTT for both sides, regardless of which side is proposing. Moreover, GS is the unique RFTT mechanism within the class of quantile-stable matching mechanisms. Outside that class, there are other RFTT mechanisms, but they are not natural. In particular, the Boston mechanism and top trading cycles are both not RFTT. Moreover, in a GS market, truth-telling is the unique report that guarantees no regret.
For example, suppose there are two women: Alice and Batya, and two men: Chen and Dan. The women preferences are Alice: Dan>Chen, Batya:Chen>Dan. The men preferences are Dan:Batya>None>Alice, Chen:Alice>Batya. Suppose the men are proposing. Then, with truthful reports, the matching is Dan-Batya, Chen-Alice. If Alice truncates her preferences and reports only Dan, then the matching is Batya-Chen, and Alice remains unemployed. In this case, Alice regrets not being honest, since being honest would guarantee that she is employed.
In a many-to-one matching market (such as hospitals-doctors matching), the doctor-proposing GS is RFTT for both sides, but the hospital-proposing GS is not RFTT. This supports the decision of NRMP to switch from hospital-proposing to doctor-proposing GS.
Chen and Moller study school choice mechanisms. They focus on the efficiency-adjusted deferred-acceptance rule (EADA or EDA). It is known that EDA is not strategyproof for the students; Chen and Moller show that EDA is RFTT. They also show that no efficient matching rule that weakly Pareto-dominates a stable matching rule is RFTT.
In voting
Arribillaga, Bonifacio and Fernandez study RFTT voting rules. They show that:
When a voting rule depends only on the top alternative of each agent (e.g. plurality voting), RFTT is equivalent to strategyproofness. This means that, for 3 or more outcomes, the only RFTT mechanisms are dictatorships (by the Gibbard–Satterthwaite impossibility theorem); and for 2 outcomes, a mechanism is RFTT if and only if it is an extended majority rule.
As an example, to see that plurality voting is not RFTT for 3 outcomes, suppose an agent's preference ranking is z>y>x. If he sees that x is elected, then in hindsight, voting y is a dominant strategy: it can never hurt (as x is already the worst outcome), and it can help (if y and x were tied).
For egalitarian voting rules: all neutral variants (i.e., breaking ties by a fixed order on agents) are RFTT. The anonymous variants (breaking ties by a fixed order on candidates) are RFTT iff there are at least m-1 voters, or the number of voters divides m-1.
For the veto voting rule (a scoring rule where all candidates receive 1 point except the least-preferred one who gets 0), the results are similar to the egalitarian rules. Similarly, k-approval is RFTT.
Other scoring rules may not be RFTT. In particular, Borda voting, plurality voting and Dowdall voting, and all efficient anonymous rules, are not RFTT.
All Condorcet-consistent voting rules that also satisfy a weak monotonicity condition are not RFTT. This condition holds, in particular, for the rules of Simpson, Copeland, Young, Dodgson, Fishburn and Black (in both anonymous and neutral versions). Successive elimination rules are also not RFTT.
In fair division
Tamuz, Vardi and Ziani study regret in fair cake-cutting. They study a repeated game variant of cut-and-choose. In standard cut-and-choose, a risk-averse cutter would cut to two pieces equal in his eyes. But in their setting, there is a different cutter each day, playing cut-and-choose with the same chooser. Each cutter knows all past choices of the chooser, and can potentially exploit this information in order to make a cut that will guarantee to him more than half of the cake. Their goal is to design non-exploitable protocols - protocols in which the cutter can never know what piece the chooser is going to choose, and therefore always cuts the cake into two pieces equal in his eyes. The idea is to restrict the positions in which the cutter can cut; such protocols are called forced-cut protocols. A simple non-exploitable forced-cut protocol is: in each day, take all pieces generated in the previous day (by forced and non-forced cuts), and force the cutter to cut each of these pieces into two. This protocol uses 2n cuts, where n is the number of days. There are protocols that use fewer cuts, depending on the number of dimensions of the cake:
If the cake is an n-dimensional convex set, then there is an envy-free forced-cut protocol that uses n cuts (one cut per day). Each day, the cutter is forced to make a cut in a different dimension, orthogonal to all previous cuts, so the information from previous days is not helpful.
If the cake is 1-dimensional, then:
There is an adaptive envy-free forced-cut protocol that uses 3 cuts per day. Each day, there is one adaptive forced-cut, and the cutter must make two additional cuts (one on each side of the forced cut).
There is no non-adaptive forced-cut protocol that uses any fixed number of cuts per day;
There is a non-adaptive forced-cut protocol that uses O(n2) cuts, where n is the number of days. At each day, there are n forced cuts at 1/(n+1),...,n/(n+1); the cutter must make n+1 cuts (one in each interval).
If the cake is a 2-dimensional set (e.g. a square), then there is a non-adaptive forced-cut protocol using 3 cuts per day. On each day t, there is a vertical forced cut at t/(n+1). The cutter must make a horizontal cut at each side of the vertical cut.
Cresto and Tajer also study regret in fair cake-cutting among two agents, where the regret comes from a change in preferences: after one player sees the choice of the other player, his preferences may change. They suggest a variant of cut and choose that avoids this kind of regret.
References
Mechanism design | Regret-free mechanism | [
"Mathematics"
] | 1,712 | [
"Game theory",
"Mechanism design"
] |
75,637,571 | https://en.wikipedia.org/wiki/Roger%20M.%20Rowell | Roger M. Rowell (born November 28, 1939) is an American biochemist and wood scientist of the Forest Products Laboratory at Madison and emeritus professor at the University of Wisconsin-Madison, who is an elected fellow (FIAAM) of the International Association for Advanced Materials and an elected fellow (FIAWS) of the International Academy of Wood Science.
Education and career
He obtained his bachelor of science degree in chemistry and mathematics from Southwestern College in Kansas in 1961, followed by an MSc degree in biochemistry from Purdue University in 1963. He got his PhD in biochemistry at the Purdue University in 1965, under the supervision of Professor R.L. Whistler.
Between 1966 and 2007, Rowell served as a leading research chemist at the USDA – Forest Products Laboratory in Madison, Wisconsin, with professorship appointments in the departments of Forestry and Biological Systems Engineering at the University of Wisconsin in Madison.
Since 2009, he holds the title of emeritus professor at the University of Wisconsin-Madison. His work includes more than 300 research papers, several international patents, and many conference presentations. Rowell's primary research has focused on biomaterials, wood chemistry, carbohydrate chemistry and chemical modification of wood.
He has been a visiting professor and scholar at several research institutes and universities in countries such as Japan, Sweden, China, Norway, South Korea, New Zealand. Rowell has served as a member of the editorial boards of various journals, including Forest Products Journal, Wood Science and Technology, and Wood Material Science and Engineering.
Recognition
In 1991, Rowell received an award from the American Chemical Society for his research contributions in wood chemistry, primarily related to the acetylation of wood.
Rowell has been an elected fellow in the Cellulose, Paper and Textile Division of the American Chemical Society, and also, a fellow in the Japan Society for the Promotion of Science. In 2009 he received the Outstanding Scientist Award of the USDA Forest Service as the research scientist of the year.
In October 2023, a referenced meta-research conducted by John Ioannidis and his team at Stanford University included Roger M. Rowell in Elsevier Data 2022, where he was ranked in the global top 2% of researchers of all time in the area of wood chemistry (forestry – chemistry).
Personal life
Rowell lives permanently in Madison, Wisconsin. He has been married with Judith Kay since 1961, and they have three children and eight grandchildren.
Books
Handbook of Wood Chemistry and Wood Composites (2005), Taylor and Francis, Boca Raton, FL, 487 pp
Paper and composites from agro-based resources (1996), CRC Lewis Publishers, Boca Raton, FL, 446 pp.
Materials interactions relevant to recycling of wood-based materials (1992), Materials Research Society Symposium Proceedings, Vol 266, 306 pp.
Emerging technologies for materials and chemicals from biomass (1992), Symposium Series 476, Am. Chem. Soc., Washington, D.C., 469 pp.
Archaeological Wood: Properties, Chemistry, and Preservation (1990), American Chemical Society Advances in Chemistry Series 225, Washington, DC, 472 pp.
Chemistry of Solid Wood (1984), American Chemical Society, Advances in Chemistry Series No. 207, Washington, D.C., 614 pp.
References
External links
Google Scholar
Scopus
University of Wisconsin–Madison faculty
Purdue University alumni
American scientists
Fellows of the International Academy of Wood Science
Wood scientists
1939 births
Living people | Roger M. Rowell | [
"Materials_science"
] | 702 | [
"Wood sciences",
"Wood scientists"
] |
75,638,809 | https://en.wikipedia.org/wiki/Tearful%20salutation | Tearful salutation or tearful greeting refers to a practice common among various indigenous groups in the Americas. Documented prominently among the Tupinambás, it involves a tearful ceremony when a foreigner or absent tribe member arrives in the village.
Distribution
The tearful salutation in South America was limited to the region east of the Andes. According to Alfred Métraux, it was the Tupi people who spread this custom. In relation to North America, the habit was widespread in the region between the headwaters of the Mississippi River and the coast of Texas, especially among the Kaddö group and the Sioux Indians. Georg Friederici reported finding evidence of the tearful salutation in Central America. Outside the American continent, it is observed in the Andaman Islands, Australia (in Queensland), and New Zealand.
Description
Among the Tupinambá people, the tearful salutation occurred when a foreigner or a tribe member absent for more than four days approached the host's dwelling. The guest would then lie down in a hammock; subsequently, the women of the dwelling gathered around, embracing him, placing their hands on his shoulders, neck, and knees, and covering his face with their hair. Squatting down, they would finally start to cry, sobbing and reciting speeches in rhymed prose. According to Claude d'Abbeville, they mentioned the guest was welcome and should be esteemed. According to , they also recalled the ancestors. stated they commented on what had happened while they were apart, imagining the difficulties the guest might have faced on the way. The guest had the obligation to cry as well, or at least cover his face and sigh. The crying only ceased upon request, which, however, was considered impolite. When the practice finally ended, a common greeting was heard: "" ().
The tearful salutation was also observed in various other indigenous groups, such as the Charruas and the Lenguas. Among the Guaranis, the practice was exactly the same as that of the Tupinambás. Karl von den Steinen observed two Jurunas greeting each other with tears. found the existence of the tearful salutation among the Carajás and the Kaiapós as well; relatives, upon meeting, remain silent and avoid looking at each other for a few minutes, and women cry for a brief period of time. The Oiampis, when encountering someone who has been absent for some time, turn their backs and remain silent for about ten minutes, indicating a trace of the practice. Jivaro women sing funeral songs when receiving outsiders.
Interpretation
Georg Friederici interprets the tearful salutation as an expression of sympathy for the guest, who would have faced dangers to visit the host. For Rafael Karsten, the custom would be an expression of pain caused by memories of deceased relatives, awakened by the visit. Alfred Métraux suggests some connection with the cult of the dead.
Notes
References
Bibliography
External links
Crying
Greetings
Indigenous people of the Americas
Meetings | Tearful salutation | [
"Biology"
] | 615 | [
"Crying",
"Behavior",
"Human behavior"
] |
75,639,463 | https://en.wikipedia.org/wiki/Aluminium%20gallium%20antimonide | Aluminium gallium antimonide, also known as gallium aluminium antimonide or AlGaSb (AlxGa1-xSb), is a ternary III-V semiconductor compound. It can be considered as an alloy between aluminium antimonide and gallium antimonide. The alloy can contain any ratio between aluminium and gallium. AlGaSb refers generally to any composition of the alloy.
Preparation
AlGaSb films have been grown by molecular beam epitaxy, chemical beam epitaxy and liquid phase epitaxy on gallium arsenide and gallium antimonide substrates. The result is a layered heterostructure on various III-V compounds.
Electronic properties
The bandgap and lattice constant of AlGaSb alloys are between those of pure AlSb (a = 0.614 nm, Eg = 1.62 eV) and GaSb (a = 0.610 nm, Eg = 0.73 eV). At an intermediate composition, the bandgap transitions from an indirect gap, like that of pure AlSb, to a direct gap, like that of pure GaSb. Different values of the composition at which this transition occurs have been reported over time, both from computational and experimental studies, with reported values ranging from x = 0.23 to x = 0.43. The spread in the reported values of the transition is mainly due to the closeness of the gap sizes at the Γ and L points in the Brillouin zone and variations in the experimentally-determined gap sizes.
Applications
AlGaSb has been incorporated into devices such as heterojunction bipolar and high-electron-mobility transistors, resonant-tunneling diodes, solar cells, short-wave infrared lasers, and a novel infrared light modulator. It is sometimes selected as an interlayer or buffer layer in studies of GaSb and InAs quantum wells.
Al-rich AlGaSb is sometimes selected over AlSb in heterostructures for being more chemically stable and resistant to oxidation than pure AlSb.
References
Antimonides
Aluminium compounds
Gallium compounds
III-V compounds | Aluminium gallium antimonide | [
"Chemistry"
] | 434 | [
"III-V compounds",
"Inorganic compounds"
] |
75,639,840 | https://en.wikipedia.org/wiki/HD%2021819 | HD 21819, also designated as HR 1073, is a solitary star located in the northern circumpolar constellation Camelopardalis. It has an apparent magnitude of 5.97, making faintly visible to the naked eye under ideal conditions. The object is located relatively close at a distance of 248 light-years based on Gaia DR3 parallax measurements and it is drifting closer with a heliocentric radial velocity of . At its current distance, HD 21819's brightness is diminished by an interstellar extinction of 0.17 magnitudes and it has an absolute magnitude of +1.62.
HD 21819 has a stellar classification of A3 V, indicating that it is an ordinary A-type main-sequence star that is generating energy via hydrogen fusion at its core. Abt & Morell (1995) gave a slightly hotter star of A2 Vp, indicating that it is instead an Ap star with weak magnesium lines. It has twice the mass of the Sun and 2.06 times the radius of the Sun. It radiates 30.6 times the luminosity of the Sun from its photosphere at an effective temperature of , giving it a white hue when viewed in the night sky. HD 21819 is metal deficient with an iron abundance of [Fe/H] = −0.17 or 67.6% of the Sun's and it is estimated to be 737 million years old, having completed 55.7% of its main sequence lifetime. Like most hot stars it spins rapidly, having a projected rotational velocity of .
References
A-type main-sequence stars
Camelopardalis
BD+54 00693
021819
016599
1073
00316848255 | HD 21819 | [
"Astronomy"
] | 355 | [
"Camelopardalis",
"Constellations"
] |
75,640,014 | https://en.wikipedia.org/wiki/Ibrahim%20Eltayeb | Ibrahim Abdelrazzak Eltayeb () is a Sudanese mathematician and professor of applied mathematics at the University of Nizwa in Oman. He is a member of the African Academy of Sciences, the Royal Astronomical Society, The World Academy of Sciences (TWAS) and the Royal Society of Edinburgh.
Early life and education
Eltayeb was born in a village on the Nile river, about 500 km north of Khartoum in Sudan, where he attended government schools. He studied in the United Kingdom on a scholarship and received a BSc in mathematics from the University of London in 1968. In 1972, he obtained his PhD in mathematics from the University of Newcastle upon Tyne.
Career and research
Eltayeb began as a lecturer at the University of Khartoum in 1972 and was promoted to professor in 1980. He served as the dean of the university's Faculty of Mathematical Sciences from 1982 to 1984. In 1986, he moved to the Sultan Qaboos University in Oman, where he established the Department of Mathematics and Computing and directed it from 1988 to 1998. Following this, he served as professor of applied mathematics at the University of Nizwa in Oman.
Eltayeb has published more than 50 papers in journals, mainly in the fields of geophysics, geomagnetism, and aeronomy. He has also developed mathematical models and methods for studying the Earth's deep interior.
Honours and awards
Eltayeb was elected a fellow of the African Academy of Sciences in 1986, the Royal Astronomical Society of London in 1988, The World Academy of Sciences (TWAS) in 1996, and the Royal Society of Edinburgh in 2012. He received the TWAS Prize in Mathematics in 1995 and the COMSTECH Award in Mathematics in 2007. He served on the executive committee of the International Association of Geomagnetism and Aeronomy (IAGA) from 1991 to 1999 and chaired the scientific division I of IAGA on internal fields and secular variations from 1999 to 2003. He has been a member of the council of the Study of the Earth's Deep Interior (SEDI) since 1987 and was on the awards committee for mathematics international prize of TWAS from 1998 to 2006.
References
External links
Profile at TWAS
Profile at Royal Society of Edinburgh
Sudanese mathematicians
20th-century mathematicians
21st-century mathematicians
Applied mathematicians
Academic staff of the University of Nizwa
Academic staff of Sultan Qaboos University
Academic staff of the University of Khartoum
Alumni of the University of London
Alumni of Newcastle University
Fellows of the African Academy of Sciences
Fellows of the Royal Astronomical Society
Fellows of the Royal Society of Edinburgh
Year of birth missing (living people)
Living people
TWAS fellows | Ibrahim Eltayeb | [
"Mathematics"
] | 542 | [
"Applied mathematics",
"Applied mathematicians"
] |
75,640,090 | https://en.wikipedia.org/wiki/List%20of%20largest%20video%20game%20companies%20by%20revenue | This is a listing of largest video game publishers and developers ranked by reported revenue over $100 million. Sony Interactive Entertainment is the world's largest video game company, followed by Tencent and Microsoft Gaming. Out of the 59 largest video game companies, 14 are located in the United States, 11 in Japan, and 7 in South Korea.
Warner Bros. Games, Annapurna Interactive and Valve Corporation are not included in this list. Warner Bros. Games is a subsidiary of a larger company, and Annapurna Interactive and Valve Corporation are private companies, and there is no available data or estimate pertaining to their revenues. Before Microsoft Gaming acquired Activision Blizzard in 2023, they reported a revenue of $8.8 billion, which would make them the 6th biggest publisher on this list.
Companies
See also
List of video game publishers
List of largest video game employers
References
Video game industry
Video game publishers
Video game lists | List of largest video game companies by revenue | [
"Technology"
] | 184 | [
"Computing-related lists",
"Video game lists"
] |
75,640,894 | https://en.wikipedia.org/wiki/NATRAX | NATRAX (National Automotive Test Track), Pithampur, Dhar District, Madhya Pradesh, is Asia's longest and one of the high-speed state-of-the-art tracks in India for automotive testing and certification. It is the fifth largest track in the world.
Background
The 11.3-km high-speed track is built under NATRiP (National Automotive Testing and R&D Infrastructure Project), a project of the Ministry of Heavy Industries, Government of India, has an area of approximately 3000 acres and the track is developed in an area of about 1000 acres at a cost or Rs.1321 crores. The Automotive Mission Plan (2016–26) is a vision document by Government of India that was planned for the development of the industry in pursuit of economic growth and the track was part of it. It is located near the industrial township of Pithampur, in Dhar district of Madhya Pradesh. It is 50 km from the Indore, and is on the NH-52 by-pass road which connects Indore to Mumbai.
An auto show was held at NATRAX in May 2022. About 80 super cars and 60 super bikes from Indore, Bhopal and Delhi took part in different races at the show. The three-day show attracted about 1200 visitors, including students.
Track
It has two semi-circular curves that can test vehicles at a maximum neutral speed of 250 km per hour. The track can offer maximum speeds of 375 kmph on the curves with steering control. A lot of different tests, including measurement of maximum speed, acceleration, coast down, brake fade, constant speed fuel consumption, emission tests through real-road driving simulation, can be conducted at this track. It is also a Centre of Excellence (CoE) for vehicle dynamics.
The Minister of Heavy Industries and Public Enterprises Prakash Javadekar inaugurated the track on 29 June 2021. Dr. N. Karuppaiah is the centre head for the track. The track is also suitable for motorsports events but is yet to be homologated by the motorsports federations FIA or FIM. It is yet to get NABL accreditation to be able to issue homologation certificates to OEMs.
Facilities
Test tracks: High-speed track - The high-speed 11.3-km four-lane track is used to develop and homologate all kinds of vehicles. Original Equipment Manufacturers (OEM) can conduct all kinds of tests at one place.
Dynamic platform: The vehicle dynamic platform is the 300-metre steering pad and is connected to 1500-metre long-vehicle dynamic test area.
Multi-friction braking track: With a mu range from 0.15 to 0.9, the Braking Track can conduct braking tests on various surfaces like basalt, ceramic, high-friction asphalt and polish concrete for homologation.
NATRAX also has a gradient track, fatigue track, gravel and off-road track, handling track, comfort track, sustainability track and other facilities like noise track and wet-skid pad.
References
External links
NATRAX
Road transport
Vehicle technology
Road test tracks
Vehicle industry
Automotive industry
Research and development in India
Automotive industry in India | NATRAX | [
"Engineering"
] | 642 | [
"Vehicle technology",
"Mechanical engineering by discipline"
] |
75,641,385 | https://en.wikipedia.org/wiki/Observation.org | Observation.org is a worldwide platform of naturalists, citizen scientists, and biologists to collect, validate and share biodiversity observations. Observation.org may be accessed via its website or from its mobile applications like ObsIdentify. The Observation.org database holds 233 million nature observations and 79 million photos. It is published and hosted in the Netherlands under Dutch and European law by the non-profit foundation Observation International.
History
The history of Observation International started in 2003 with the website Waarneming.nl. In 2017 Waarneming.nl counted 50 million observations. Waarneming.be followed in 2008. There were 5000 daily visitors and a total of 1.5 million after 5 years. During the COVID-19 pandemic location data of observations were hidden to prevent gathering of bird watchers.
Quality assurance
Quality assurance measures on Observation.org is managed by established species experts responsible for curating the reference set of observations. Automated validation, supported by artificial intelligence, uses this reference set to aid validators in managing the extensive dataset. However, human experts retain final authority in all validation matters.
Open data
The observations that have been approved are shared as open data on Global Biodiversity Information Facility (GBIF). The dataset comprises approximately 82 million occurrences, 19 million annotated photos and 69,000 annotated sound recordings. Observation.org is the third largest publisher of the world on GBIF.
Use of Observation.org data
As of December 2023, more than 1,700 research results have been published that cite the Observation.org dataset on GBIF, often in the fields of ecology, conservation, climate change. This research includes for example the discovery of new species for a country , documentation of changes in behavior, monitoring invasive alien species, finding causes of local extinction and tracking zoonoses such as Avian influenza. Other examples are the integration of nature data into national research programmes and European biodiversity projects. The annotated Observation.org photos are used to train automatic species recognition models.
Users of Observation.org regularly participate in Bioblitzes to collaboratively collect nature observations. Examples of these Bioblitzes are the City Nature Challenge and the Biomaratón de Otoño in Spain.
Public Perception
The UK Centre for Ecology & Hydrology recommends the app ObsIdentify beside others for detection of alien species.
As apps for identification NatureSpot recommends seek and ObsIdentify.
The Sussex Wildlife Trust finds that ObsIdentify works particularly well with invertebrates.
ObsIdentify, iNaturalist, seek, iRecord and Picture This are the favorite identifying apps for the Natural History Society of Northumbria (NHSN)
Birdwatch (magazine) UK draws a positive conclusion after testing ObsIdentify. It is easy to use and provides a lot of information.
International names
In the Netherlands, Observation.org is primarily known as Waarneming.nl. In the Dutch Caribbean, the name Observation.org is used. In Belgium, the platform is primarily known as Waarnemingen.be (Flanders) and Observations.be (Wallonia).
References
External links
GBIF page for Observation.org
Biodiversity databases
Citizen science | Observation.org | [
"Biology",
"Environmental_science"
] | 648 | [
"Biodiversity databases",
"Environmental science databases",
"Biodiversity"
] |
75,641,952 | https://en.wikipedia.org/wiki/Bert%20Peletier | Lambertus Adrianus "Bert" Peletier (29 March 1937 – 16 December 2023) was a Dutch mathematician. He was a professor of analysis and applied mathematics at Leiden University from 1977 until his retirement in 2002.
Life
Lambertus Adrianus Peletier was born on 9 March 1937 in Rijswijk. His grandfather was a socialist Dutch minister in the Dutch Reformed Church, who lived with his family during World War II. Peletier's father was an engineer working for Shell plc and took him to his laboratory. He was interested in technique from a young age and desired to pursue a technical study. His maths teacher inspired him to study physics.
Peletier thus studied theoretical physics at Delft University of Technology. After graduating, Peletier had the opportunity to study one year at the Massachusetts Institute of Technology and became inspired by academic life. In 1967 he obtained his PhD at Eindhoven University of Technology, with a thesis titled: "On a class of wave equations". He subsequently spent time abroad at the University of Sussex and University of Minnesota and became more inspired by applied mathematics. In 1977 he became professor of analysis and applied mathematics at Leiden University. He retired in 2002.
His expertise lay in the field of nonlinear analysis. During the latter part of his career, in the late 1990s, he applied mathematics for the development of medicine. He especially focused on the latter after his retirement and worked intensively with pharmacologists. In 1995 he was one of the founders of the Lorentz Center, an institute for the organization of interactive workshops in the sciences.
Peletier was elected a member of the Academia Europaea in 1989. He was elected a member of Royal Netherlands Academy of Arts and Sciences in 1999. Peletier was elected a Fellow of the Society for Industrial and Applied Mathematics in 2009. In April 2013 Peletier was made a Knight in the Order of the Netherlands Lion.
Peletier died in Leiden on 16 December 2023, at the age of 86.
References
External links
Profile at the Mathematics Genealogy Project
1937 births
2023 deaths
20th-century Dutch mathematicians
21st-century Dutch mathematicians
Academic staff of Leiden University
Applied mathematicians
Delft University of Technology alumni
Eindhoven University of Technology alumni
Fellows of the Society for Industrial and Applied Mathematics
Knights of the Order of the Netherlands Lion
Mathematical analysts
Members of Academia Europaea
Members of the Royal Netherlands Academy of Arts and Sciences
People from Rijswijk | Bert Peletier | [
"Mathematics"
] | 492 | [
"Applied mathematics",
"Mathematical analysis",
"Applied mathematicians",
"Mathematical analysts"
] |
75,642,287 | https://en.wikipedia.org/wiki/Macrophage-activating%20lipopeptide%202 | Macrophage-activating lipopeptide 2 (MALP-2) is a lipopeptide Toll-like receptor (TLR)-2 and 6 agonist. It is used in immunological research to simulate Mycoplasma bacterial infections and activate immune cells. MALP-2 holds promise as a novel vaccine adjuvant due to its activation of TLRs. It also promotes vascular, bone, and wound healing.
Structure
MALP-2 has the structure S-2,3-bis(palmityloxy)-(2R)-propyl-cysteinyl-GNNDESNISFKEK and is a post-translationally modified CGNNDESNISFKEK peptide in which in the N-terminus cysteine residue sidechain is linked to a diacylglycerol moiety where the two acyl groups are both derived from palmitic acid.
Discovery
MALP-2 was initially named mycoplasma-derived high-molecular-weight material (MDHM) and, as the name suggests, had originally been isolated from Mycoplasma fermentans as an amphiphilic molecule with macropage-activating properties. This discovery helped explain how Mycoplasma bacteria can provoke immune responses despite lacking a cell wall.
References
Lipopeptides
Immunology | Macrophage-activating lipopeptide 2 | [
"Biology"
] | 281 | [
"Immunology"
] |
75,642,557 | https://en.wikipedia.org/wiki/The%20Scale%20of%20the%20Universe | The Scale of the Universe is an interactive online visualization tool and website first created in 2010 by Chinese-American twins Cary and Michael Huang, based in Moraga, California. Released on Newgrounds and the Huang brothers' web page, it features a scrollbar that players can use to navigate through orders of magnitude and view various objects within such size ranges. Sliding the scrollbar to the left and right causes the screen to zoom in and out respectively, utilizing resolution independence in the process.
In 2012, Cary and Michael Huang released a sequel titled The Scale of the Universe 2, in which clicking on objects brings up infoboxes that display information about them. The current version of The Scale of the Universe 2 uses Pixi.js instead of Flash, ported by Matthew Martori.
The Scale of the Universe was featured on NASA's Astronomy Picture of the Day on October 7, 2018.
In 2020, animation studio Kurzgesagt released the app Universe in a Nutshell, which took inspiration from The Scale of the Universe.
The main-belt asteroid 10003 Caryhuang was officially named by the International Astronomical Union on June 16, 2021, partly in recognition of Cary Huang's involvement in The Scale of the Universe.
Objects measured
Less than 1 meter
1 meter to 1 terameter
1 terameter and beyond
See also
Cosmic Eye
Cosmic Voyage
Powers of Ten
References
External links
The Scale of the Universe on Newgrounds
The Scale of the Universe 2 on Newgrounds
The Scale of the Universe 2 on iOS
Internet properties established in 2010
Flash games
Length
Size
Astronomy websites
Infographics | The Scale of the Universe | [
"Physics",
"Astronomy",
"Mathematics"
] | 320 | [
"Geometric measurement",
"Scalar physical quantities",
"Distance",
"Physical quantities",
"Quantity",
"Works about astronomy",
"Size",
"Length",
"Wikipedia categories named after physical quantities",
"Astronomy websites"
] |
75,642,655 | https://en.wikipedia.org/wiki/Reika%20Yokochi | Reika Yokochi (横地玲果, born November 9, 1975 in Saga, Kyushu Prefecture, Japan; died on February 17, 2024 in Chicago, USA) was a Japanese geochemist who worked on the origin and geological behavior of volatile elements. She held the position of Research Professor in the Department of the Geophysical Sciences at the University of Chicago. Yokochi led a laboratory specializing in the purification and analysis of noble gases for dating and tracing water circulation within Earth's crust.
Education and early career
Yokochi completed her doctoral studies in earth sciences at National Polytechnic Institute of Lorraine (French: L'Institut National Polytechnique de Lorraine) in 2005, supervised by Bernard Marty. Her PhD thesis focused on understanding the origin of volatile elements in Earth. She identified noble gases of solar origin in Earth's deep mantle. She also worked out the contribution of 244Pu-decay (t1/2=81 Myr) to fissiogenic 136Xe* in the deep Earth, suggesting a protracted loss of volatiles from Earth's mantle. Between 2005 and 2008, she was a postdoctoral researcher with Neil C. Sturchio at the University of Illinois Chicago, after which she joined the University of Chicago as researcher in 2008.
Research activities
Yokochi's research focuses on noble gas geochemistry. She uses noble gases radionuclides, notably Krypton-81 (81Kr; t1/2=230,000 yr), to study the age and circulation of groundwater in major aquifers worldwide, including the Nubian Sandstone Aquifer, Floridan Aquifer, and the geothermal waters of Yellowstone. Krypton-81 is produced by cosmic rays in the atmosphere and then dissolves into rainwater, eventually seeping into groundwater. The overall abundance of krypton in the atmosphere is only about 1.10 parts per million by volume (ppmv), and within this, the fraction of 81Kr is extremely small, about 5 × 10−13. Yokochi crafted a device capable of efficiently extracting krypton from vast quantities of groundwater, thus facilitating the accurate quantification of 81Kr using Atom Trap Trace Analysis (ATTA).
In a study of the Nubian Sandstone Aquifer in Israel's Negev Desert, Yokochi and colleagues utilized radiokrypton (81Kr) to date groundwater, discovering two major water recharge events. The first, about 38,000 years ago, originated from the Mediterranean, and the second, around 361,000 years ago, from the tropical Atlantic. These events, coinciding with periods of low orbital eccentricity, reveal the sensitivity of moisture transport to orbital forcing. The study highlights groundwater's potential as a record of ancient precipitation and long-term subsurface water storage.
Application of 81Kr to the Floridan Aquifer revealed freshwater recharge from the Last Glacial Period. Additionally, it detected fossil seawater predating the Last Glacial Maximum, indicating slow seawater movement and a limited but significant exchange of solutes with the ocean, contributing to the aquifer's dolomitization.
Yokochi also conducted experiments aimed at understanding how volatile elements are trapped in ices under conditions relevant to the formation of comets and icy moons. The results of those experiments showed that ice surfaces have heterogeneous adsorption energies, influenced by initial ice-deposition temperatures and thermal annealing. Adsorption sites with higher energy play a significant role at low pressures and higher temperatures, conditions relevant to the protosolar nebula. The experiments also showed that gas trapping occurs primarily through the burial of gas adsorbed on newly formed ice surfaces. Yokochi's experiments indicate that the formation temperature of comet 67P/Churyumov-Gerasimenko, as suggested by the observed Ar/H2O ratio, was around 40 K.
Yokochi contributed to the analysis of gases in samples returned from the Ryugu asteroid by JAXA's Hayabusa2 mission.
Awards and recognition
Yokochi received the Young Scientist Award from the Geochemistry Research Association of Japan in 2012; the same year, she was also named a NASA Planetary Science Early Career Fellow.
Personal life
Reika Yokochi was married to Nicolas Dauphas, a fellow planetary scientist; the couple has two children. She died on February 17, 2024 from EGFR-driven lung cancer, a disease that disproportionately affects nonsmoking women of East asian ancestry. Air pollution by particles less than 2.5 microns in diameter seems to be a factor contributing to the onset of EGFR-driven lung cancer.
References
1975 births
Living people
People from Saga Prefecture
Japanese geochemists
21st-century Japanese women scientists | Reika Yokochi | [
"Chemistry"
] | 972 | [
"Geochemists",
"Japanese geochemists"
] |
75,643,536 | https://en.wikipedia.org/wiki/Alternation%20of%20supports | Alternation of supports is a trait of Romanesque architecture (and Early Gothic), where the supports in a colonnade or arcade have different types. For example, periodic change between the strong supports (piers) and the weak ones (columns) provides visually obvious alternating supports. More subtle alternation can result, for example, from variations of the column shafts.
An early example of technique used for a decorative purpose can be found in Hagios Demetrios, a 5th century Byzantine church in Thessaloniki.
The technique became common at the end of the 10th century and appears to be coupled with the use of transverse arches: the arches rested on the tops of the stronger piers. The double-bay system, with its side aisles at a half of the width of the nave, required columns for the aisle vaults placed at half the step for the transverse arches of the nave, the additional columns sometimes carried smaller load and thus can be thinner.
The use of alternating supports was largely abandoned with the introduction of Gothic architecture and its more malleable pointed arches. There were some notable exceptions, however: for example, the lateral aisles of the Notre-Dame de Paris have alternating piers of lower and greater strength that provide a "powerful appeal to the eye and the senses", but had originally fulfilled a structural need, as the heavier piers carried an extra load from the intermediate supports in the buttress system. Also, the alternation can be found in some early Gothic designs of sexpartite vaults, where the support for the middle transverse rib carries less load.
Geography
The alternating supports became popular in Europe in the 11th century (early examples started to appear in the 9th century), with the use gradually transitioning from the decorative function to support for the double-bay system.
Italian architecture of the 11th and 12th century actively used the alternating system. However, frequently the column and pier alternation was used for purely decorative purposes, most likely following the Byzantine idea found in the Hagios Demetrios. Examples include San Miniato al Monte (), San Clemente al Laterano (dedicated in 1128), Santa Maria in Cosmedin (1123), Basilica di San Nicola in Bari (1197). The alternation was also used structurally, as in Modena Cathedral (1099-1184), probably as an evolution of the decorative use.
The second area of the frequent use of the alternation was Germany, with the earliest example still standing of the church of Saint Cyriakus, Gernrode (-1014). St. Michael's Church, Hildesheim (1022), Hildesheim Cathedral (1061), and Gandersheim Abbey (1094) form an 11th-century group of churches in Saxony with alternate supports in the "dactyl" arrangement (one pier-two columns in repetition). Dactyl pattern was not new to Saxony in the 11th century, as it was used previously in Gernrode and, likely, in the old Hildesheim Cathedral (852-872). Another group of churches with alternating piers and columns is located in former Lower Lorraine: Abbey of Echternach (1016-1031), church in Zyfflich (early 11th century), Susteren Abbey (mid-11th century), Lobbes Abbey (11th century). The group might also include St Bavo's Cathedral, Ghent. The churches in Lower Lorraine use simple alternation (pier-column) as a base of the double bay system, but without the galleries. A fully developed double bay system with galleries can be found in the church of Soignies.
The use of alternating supports was not common in Normandy, with notable exceptions of Jumièges Abbey (1052-1066) and Lyre Abbey (12th century), the former being an early example of a double-bay transition.
References
Sources
Romanesque architecture
Architectural terminology | Alternation of supports | [
"Engineering"
] | 804 | [
"Architecture stubs",
"Architectural terminology",
"Architecture"
] |
68,437,256 | https://en.wikipedia.org/wiki/Plethystic%20exponential | In mathematics, the plethystic exponential is a certain operator defined on (formal) power series which, like the usual exponential function, translates addition into multiplication. This exponential operator appears naturally in the theory of symmetric functions, as a concise relation between the generating series for elementary, complete and power sums homogeneous symmetric polynomials in many variables. Its name comes from the operation called plethysm, defined in the context of so-called lambda rings.
In combinatorics, the plethystic exponential is a generating function for many well studied sequences of integers, polynomials or power series, such as the number of integer partitions. It is also an important technique in the enumerative combinatorics of unlabelled graphs, and many other combinatorial objects.
In geometry and topology, the plethystic exponential of a certain geometric/topologic invariant of a space, determines the corresponding invariant of its symmetric products.
Definition, main properties and basic examples
Let be a ring of formal power series in the variable , with coefficients in a commutative ring . Denote by
the ideal consisting of power series without constant term. Then, given , its plethystic exponential is given by
where is the usual exponential function. It is readily verified that (writing simply when the variable is understood):
Some basic examples are:
In this last example, is number of partitions of .
The plethystic exponential can be also defined for power series rings in many variables.
Product-sum formula
The plethystic exponential can be used to provide innumerous product-sum identities. This is a consequence of a product formula for plethystic exponentials themselves. If denotes a formal power series with real coefficients , then it is not difficult to show that:The analogous product expression also holds in the many variables case. One particularly interesting case is its relation to integer partitions and to the cycle index of the symmetric group.
Relation with symmetric functions
Working with variables , denote by the complete homogeneous symmetric polynomial, that is the sum of all monomials of degree k in the variables , and by the elementary symmetric polynomials. Then, the and the are related to the power sum polynomials: by Newton's identities, that can succinctly be written, using plethystic exponentials, as:
Macdonald's formula for symmetric products
Let X be a finite CW complex, of dimension d, with Poincaré polynomialwhere is its kth Betti number. Then the Poincaré polynomial of the nth symmetric product of X, denoted , is obtained from the series expansion:
The plethystic programme in physics
In a series of articles, a group of theoretical physicists, including Bo Feng, Amihay Hanany and Yang-Hui He, proposed a programme for systematically counting single and multi-trace gauge invariant operators of supersymmetric gauge theories. In the case of quiver gauge theories of D-branes probing Calabi–Yau singularities, this count is codified in the plethystic exponential of the Hilbert series of the singularity.
References
Symmetric functions | Plethystic exponential | [
"Physics",
"Mathematics"
] | 631 | [
"Sequences and series",
"Symmetry",
"Mathematical structures",
"Symmetric functions",
"Generating functions",
"Algebra"
] |
68,438,168 | https://en.wikipedia.org/wiki/FLEUR | The FLEUR code (also Fleur or fleur) is an open-source scientific software package for the simulation of material properties of crystalline solids, thin films, and surfaces. It implements Kohn-Sham density functional theory (DFT) in terms of the all-electron full-potential linearized augmented-plane-wave method. With this, it is a realization of one of the most precise DFT methodologies. The code has the common features of a modern DFT simulation package. In the past, major applications have been in the field of magnetism, spintronics, quantum materials, e.g. in ultrathin films, complex magnetism like in spin spirals or magnetic Skyrmion lattices, and in spin-orbit related physics, e.g. in graphene and topological insulators.
Simulation model
The physical model used in Fleur simulations is based on the (F)LAPW(+LO) method, but it is also possible to make use of an APW+lo description. The calculations employ the scalar-relativistic approximation for the kinetic energy operator. Spin-orbit coupling can optionally be included. It is possible to describe noncollinear magnetic structures periodic in the unit cell. The description of spin spirals with deviating periodicity is based on the generalized Bloch theorem. The code offers native support for the description of three-dimensional periodic structures, i.e., bulk crystals, as well as two-dimensional periodic structures like thin films and surfaces. For the description of the exchange-correlation functional different parametrizations for the local density approximation, several generalized-gradient approximations, Hybrid functionals, and partial support for the libXC library are implemented. It is also possible to make use of a DFT+U description.
Features
The Fleur code can be used to directly calculate many different material properties. Among these are:
The total energy
Forces on atoms
Density of states (including projections onto individual atoms and orbitals characters)
Band structures (including projections onto individual atoms and orbitals characters and band unfolding)
Charges, magnetic moments, and orbital moments at individual atoms
Electric multipole moments and magnetic dipole moments
Heisenberg interaction parameters (via the magnetic force theorem or via comparing different magnetic structures)
Magnetocrystalline anisotropy energy (via the magnetic force theorem or via comparing different magnetic structures)
Dzyaloshinskii-Moriya interaction parameters (via the magnetic force theorem or via comparing different magnetic structures)
Spin-spiral dispersion relations (via the magnetic force theorem or via comparing different magnetic structures)
EELS spectra
Magnetic circular dichroism spectra
The Work function for surfaces
For the calculation of optical properties Fleur can be combined with the Spex code to perform calculations employing the GW approximation to many-body perturbation theory. Together with the Wannier90 library it is also possible to extract the Kohn-Sham eigenfunctions in terms of Wannier functions.
See also
List of quantum chemistry and solid state physics software
References
External links
The FLEUR project
Computational chemistry software
Density functional theory software
Physics software | FLEUR | [
"Physics",
"Chemistry"
] | 639 | [
"Computational chemistry software",
"Chemistry software",
"Computational physics",
"Computational chemistry",
"Density functional theory software",
"Physics software"
] |
68,439,489 | https://en.wikipedia.org/wiki/S139%20Booster | The S139 (S for Solid, 139 for weight of 139 tonnes) is a Solid Rocket Booster manufactured by the Indian Space Research Organisation at the Satish Dhawan Space Centre in the SPROB facility. The rocket motor was first developed for use in the Polar Satellite Launch Vehicle. Later it was utilised in the GSLV MKII. It uses hydroxyl-terminated polybutadiene (HTPB) as a propellant. It has a maximum thrust of 4800 kN.
Associated rockets
The S139 Booster has been used in 2 major ISRO rockets.
It is used in the PSLV as its core stage since 1993.
It is also used as a core stage in Geosynchronous Satellite Launch Vehicle MKII rocket.
It is also the part of a variant of the Unified Launch Vehicle which is under development.
Gallery
References
Rocket stages
Satish Dhawan Space Centre
Solid-fuel rockets
ISRO space launch vehicles
Expendable space launch systems
Polar Satellite Launch Vehicle
Geosynchronous Satellite Launch Vehicle | S139 Booster | [
"Astronomy"
] | 213 | [
"Rocketry stubs",
"Astronomy stubs"
] |
68,440,645 | https://en.wikipedia.org/wiki/Noreen%20Sher%20Akbar | Noreen Sher Akbar is a Pakistani applied mathematician specializing in fluid dynamics. After obtaining her Ph.D. in 2012, from Quaid-i-Azam University, she joined the faculty at National University of Sciences & Technology, where she is head of the Department of Basic Sciences and Humanities.
Akbar has won multiple honours for her research productivity including being listed as a Young Associate of the Pakistan Academy of Sciences. She was the 2012 winner of the Best Young Scientist award of the National Academy of Young Scientists, and the 2017 winner of the M. Raziuddin Siddiqi Prize and Gold Medal of the Pakistan Academy of Sciences.
References
External links
Year of birth missing (living people)
Living people
Pakistani mathematicians
Pakistani women academics
Fluid dynamicists
Quaid-i-Azam University alumni
Academic staff of the National University of Sciences & Technology | Noreen Sher Akbar | [
"Chemistry"
] | 169 | [
"Fluid dynamicists",
"Fluid dynamics"
] |
68,440,880 | https://en.wikipedia.org/wiki/Samarium%28III%29%20nitrate | Samarium(III) nitrate is an odorless, white-colored chemical compound with the formula Sm(NO3)3. It forms the hexahydrate, which decomposes at 50°C to the anhydrous form. When further heated to 420°C, it is converted to the oxynitrate, and at 680°C it decomposes to form samarium(III) oxide.
Synthesis
Samarium(III) nitrate is produced by the reaction of samarium hydroxide and nitric acid:
Uses
Samarium(III) nitrate is a lewis acid catalyst that is used to produce a nitrate precursor solution that is used as a nanocatalyst in the solid oxide regenerative fuel cells. The nanocatalyst is made by mixing samarium(III) nitrate hexahydrate, strontium nitrate, and cobalt(II) nitrate hexahydrate.
Samarium(III) nitrate is also used for the preparation of samarium doped ceria, which can be used in the fabrication of electrolytes for fuel cells. The samarium doped ceria is produced by mixing cerium(III) nitrate and samarium(III) nitrate together using triethylene glycol as a solvent for 5 hours at 200°C. Then it was dried for 4 hours at 110°C which resulted in a brown solid. Then it was heated up to 500°C for two hours which made the samarium doped ceria.
References
Nitrates
Acid catalysts
Samarium(III) compounds | Samarium(III) nitrate | [
"Chemistry"
] | 320 | [
"Acids",
"Acid catalysts",
"Nitrates",
"Oxidizing agents",
"Salts"
] |
68,442,235 | https://en.wikipedia.org/wiki/Weather%20forecasting%20for%20Operation%20Overlord | The Overlord planners for the invasion of Europe in 1944 specified suitable weather (wind, cloud, tidal and moon conditions) for the assault landing; with only a few days in each month suitable. In May and June 1944 frequent pre-assault meetings were held at Southwick House in Hampshire near Portsmouth by Eisenhower with Group Captain James Stagg of the RAF, the Chief Meteorological Officer, SHAEF, his deputy Colonel Donald Yates of the USAAF, and his three two-man teams of meteorologists. Stagg was a "dour but canny Scot.. " He had been given the rank of group captain in the RAF "to lend him the necessary authority in a military milieu unused to outsiders". The senior commanders were General Bernard Montgomery, Admiral Sir Bertram Ramsay and Air Marshal Sir Trafford Leigh-Mallory, plus Eisenhower's deputy, Air Marshall Arthur Tedder, his chief of staff Walter Bedell Smith and his deputy chief of Staff Major General Harold R. Bull.
Stagg reported the team consensus, although this has been glossed over in popular memory. Admiral Sir George Creasy remarked on 4 June: "Here comes six feet two inches of Stagg and six foot one inch of gloom....." (1.88m & 1.85m). British general Frederick Morgan (head of COSSAC) had half-jokingly said to him "Remember, if you don't read the runes (or signs) right, we'll string you up from the nearest lamppost".
Forecasting teams
The three weather forecasting teams at Southwick House were from the UK Met Office at Dunstable, the Eighth Air Force of the USAAF at High Wycombe, and the Royal Navy at Portsmouth; they usually met twice daily; at 9:30 am (0930 hours) and 4:00 pm (1600 hours), with Eisenhower and his senior commanders.
The Royal Navy team was Commander Geoffrey Wolfe and New Zealand Lieutenant Commander Lawrence Hogben. Hogben recalled that "We six never agreed on anything except that Stagg was not a good meteorologist and that he was a bit of a glory hound". At heart a geophysist, Stagg was appointed as SHAEF weatherman for his administrative skills to co-ordinate Army and RAF forecasting; he had only two years experience of forecasting in the Iraqi desert.
The civilian Met Office team was Charles K. M. Douglas and Norwegian Sverre Petterssen of the Norwegian Air Force. Douglas had told USAAF airmen Spaatz and Doolittle in 1942 that "a forecast for more than a day or two ahead in this country can be nothing more than speculation".
The USAAF team was Irving P. Krick and Ben Holtzman. Hogben thought their forecasts for daylight bombing runs over Germany made by looking at forty years of weather maps were "pure bunk" and the Norwegian Petterssen thought that Krick was "talking nonsense" in claiming reliable forecasts for up to five days. Pre-war they had forecasted for Hollywood film studios (e.g. for the "burning of Atlanta" scene in Gone with the Wind). Krick (a physics graduate and college professor) was regarded by his rivals as "brash" and "a salesman to his fingertips". Donald Yates was a former student of Krick. The American team was based at the USAAF facility Widewing used for SHAEF HQ at Camp Griffiss in Bushy Park near Teddington.
Tidal predictions
A full moon was desirable, as it would provide illumination for aircraft pilots and have the highest tides. Having the landings shortly before dawn, midway between low and high tide, with the tide coming in would improve the visibility of obstacles the enemy had placed on the beach while minimising the amount of time the men had to spend exposed in the open. Specific criteria were set for wind speed, visibility, and cloud cover. The previous night had to be reasonably light (moonlight) for darkened convoys; although airborne troops needed a full or nearly full moon but late-rising so with darkness until they were dropped.
The invasion zone tidal range was about 23 ft (7m) and the landings should be on a rising tide to allow landing craft to run aground, unload and then withdraw without becoming stranded. Landings had to be at about the same time on all beaches to avoid later arrivals meeting an alerted enemy, and Omaha had an exposed tidal flat of 300 yards (275m) to cross. It was decided that the assault should be one hour after low tide and within one hour of first light.
Arthur Doodson head of the Liverpool Tidal Institute advised the Royal Navy on European coastal areas, and was asked in October 1943 by Commander Ian Farquharson to make tidal predictions for Normandy, which was disguised as "Position Z". He created two tide-prediction machines. The required light and tidal conditions occurred for only six days a month, and when strong moonlight for airborne operations was added there were only three days per month.
Choice of date for Overlord
Originally 1 May 1944 was proposed at the Trident Conference attended by Roosevelt and Churchill in May 1943, but when the invasion force was expanded from landing three divisions to landing five divisions (as proposed by Eisenhower and Montgomery), it was delayed to acquire the extra landing craft needed. This allowed more time for air attacks on the defences. Suitable dates were 21–23 May, 5–7 June, 19–21 June and 3–5 July 1944 according to Admiral Alan Kirk.
At the Tehran Conference in November–December 1943, Thursday 1 June 1944 was tentatively chosen. For long-term planning it was called Y-day, so D-day must be Y plus 4, 5 or 6. As the assault machinery must be set in motion two days before the event, D-day must be decided by Y plus 2. For early June there were only three days (5, 6 and 7 June). For H-Hour (the hour of landing) one hour of daylight was needed beforehand. Stagg had said they might have to wait 150 years for the perfect weather which would please everyone, and also that a full moon and early low tide could be guaranteed on the 4th, 5th, 6th and 7 June.
On 17 May 1944 Eisenhower chose 5 June which allowed the possibility of postponing for one or two days, although the convoys might have to be refuelled for 7 June. For 5 June, units from the north would have to depart on 3 June to arrive in time. The first to depart were the blockships to be sunk off the Normandy coast that sailed south from their Scottish ports on 31 May 1944. With bad weather on 5 June the operation was postponed for a day to 6 June, and then a slight break in the weather was predicted. As many ships had to depart one or two days beforehand some were held at sea. The bad weather had led German commanders to rule out an invasion then, so the Allied landings took them by surprise.
The next suitable dates with the right combination of tides (but without a full moon, desirable for the airborne troops) would have been 18 to 20 June. On 17 June the team forecasts were all for good weather, but on 18 June the worst storm for forty years arrived, which would have made the initial landings impossible. Eisenhower later said to Stagg: "I thank the gods of war we went when we did".
Monday 29 May to Wednesday 31 May
Weather conditions were excellent on the 20th, and Stagg gave an optimistic long-range forecast for the first week of June. Admiral Ramsay noted "another boiling hot day" on Tuesday but "slightly cooler" on Wednesday.
Thursday 1 June
The first coded messages (about 160; repeated on the 2nd and 3rd ) over the BBC's Radio Londres told the French Resistance that the invasion was expected in two weeks, e.g. the quote from Paul Verlaine's 1866 poem Chanson d'automne (sung by Charles Trenet): Les sanglots longs des violons d'automne ("The long sobs of autumn violins"). It was intercepted by the Germans at 1:20 pm. Il fait chaud à Suez ("It's hot in Suez") initiated the widespread launching of disruptive guerrilla operations.
Admiral Ramsay noted "A dull morning, Overcast with slight rain. Cooler. No doubt the general lull is but a precursor of the storm to follow."
Friday 2 June
May had been consistently fine, but less favourable weather was predicted for D-Day, with indications that the relatively quiet weather might end about 6 June. After discussion with his commanders Eisenhower decided to keep existing orders. So Bombarding Force D sailed from the Clyde, and HMZ Nelson left Scapa for Milford Haven. Two midget submarines X-20 & X-23 left; they were to mark Sword and Juno beaches for Forces S and J (Operation Gambit). Admiral Ramsay noted "1000 hours. Commander's meeting at which main topic was the change for the worse in weather, affecting air (operations) generally and the carriage of airborne troops in particular." The Blacksod lighthouse in neutral Ireland had reported a rapidly falling barometer and a Force Six wind.
Stagg conferred and argued (without agreement) with the other meteorological centres over secure landlines. To Stagg "Had it not been fraught with such potential tragedy, the whole business was ridiculous. In less than half an hour I was expected to present to General Eisenhower an "agreed" forecast for the next five days which covered the time of launching of the greatest military operation ever mounted; no two of the expert participants in the discussion could agree on the likely weather even for the next 24 hours." At the 21:30 evening meeting Stagg was asked by Eisenhower "Well, Stagg, what have you got for us this time." He followed his instincts, overlooking the optimistic American team, saying "The whole situation from the British Isles to Newfoundland has been transformed in recent days and is now potentially full of menace". Some officers glanced out the window at the beautiful sunset in slight bewilderment (on Double British Summer Time, it was still light; France was an hour behind). Asked by Eisenhower about the likely situation on 6 and 7 June; he replied after a pause "If I answered that, Sir, I would be guessing, not behaving as your meteorological advisor".
Then Stagg and Yates left and withdrew to their tented sleeping quarters; the sky was almost clear and everything around was quiet. Later that night Eisenhower was told by his aide Harry Butcher about the message accidentally put out by Associated Press (picked up by CBS and Radio Moscow) that "Eisenhower's forces are landing in France"; the agency cancelled it 23 minutes later.
Saturday 3 June
In the morning Stagg was "all but physically nauseated" by the weather charts and the different analysis by the teams. He said to the commanders at 21:30 hours "Gentleman, the fears my colleagues and I had yesterday about the weather for the next three or four days have been confirmed" and gave a detailed forecast of rough seas, winds up to force six and low cloud. All seemed temporarily stunned; Eisenhower was motionless and had to recommend a provisional postponement.
By the afternoon the weather had deteriorated, to the dismay of the Southwick House meeting at 16:15. The two British teams predicted a sudden and serious decline with storms that would rule out air support and could make landing treacherous, though the American team thought better weather was in the offing for 5 June. Petterssen presented his own weather map showing a violent storm brewing. And Ramsay noted that "The report was bad"; the low cloud predicted would prohibit the use of airborne troops and the majority of air action (including air spotting for naval gunfire). The sea conditions were "unpromising but not prohibitive".
Stagg did not get a consensus, so told Eisenhower on 3 June that the weather two days hence was unlikely to meet the Overlord planners' requirements. At the meeting Tedder was against going and Ramsay was neutral. But Montgomery was insistent on going "regardless of casualties or air support", he was opposed by Ramsay and the airmen Tedder and Leigh-Mallory. So Eisenhower postponed a go-no go decision until dawn on Sunday 4 June. Messages e.g. "Bowsprit" or "Regatta postponed 24 hours" were to go out, some were not received until 4 June. Convoy U2A from Salcome and Dartmouth left on 4 June for Utah Beach but did not receive the broadcast recall notices, and was headed for France alone (panic in Southwick House ops room!). A search by two destroyers was unsuccessful, then a Walrus reconnaissance biplane located the convoy after an all-day search and dropped two coded messages in canisters; the second one was acknowledged when the convoy was 30 miles south of the Isle of Wight and 36 miles from Normandy, after sailing 150 miles at 6 knots. The convoy of about 150 vessels was carrying the 4th Infantry Division of Major-General Raymond O. Barton, and had to be hastily refuelled at Portland.
That night Stagg said that there was good news; there should be a brief break in the bad weather that caused the postponement but that he would know more in the morning. Ramsay noted that "from mid-day on the 4th, the weather got progressively worse" and "No enemy reaction" (as they had no air patrols). He got some vessels refuelled.
Sunday 4 June
By the morning of 4 June 1944 at the 4:15 briefing, conditions were clearly unsuitable for a landing; high winds and heavy seas made it impossible to launch landing craft, and low clouds would prevent aircraft from finding their targets. Ramsay recorded that while the sea conditions were 'unpromising but not prohibitive" the predicted low cloud would prohibit the use of airborne troops (and) the majority of air action including air spotting for naval gunfire. At 13:30 de Gaulle was told of the Overlord plans by Churchill aboard Churchill's armoured train near Portsmouth; he was "revolted at not being informed earlier". Churchill had commandeered the royal train and was lurking nearby at Droxford railway station; "unhelpfully breathing down everyone's necks".
Two more weather conferences were held on 4 June, at 17:15 and 21:00. Despite the hard wind outside Stagg and the team of meteorologists advised that the wind could improve to winds of up to 18 mph (29 km/h) or force 3–4 on the Beaufort scale; a basic requirement for landing craft.
At the 21:00 (9 pm) meeting rain and wind was battering the windows but Stagg said "Gentleman, since I presented the forecast last evening some rapid and unexpected developments have occurred over the North Atlantic". With a brief improvement from Monday afternoon the weather would not be ideal but it would do. Ramsay made it clear that if Overlord proceeded on Tuesday he would need to issue provisional warnings in the next half-hour, but if they restarted and were recalled again there was no question of continuing on Wednesday. Petterssen predicted a 36-hour gap of acceptable weather (some later American accounts ignore the American teams' proposal to go on the 5th, and credit them with seeing the improved weather gap on the 6th).
Ramsay wrote that "we decided to take a chance and go ahead; while the grounds were not good it seemed to be Tuesday – or not this week at all" and Eisenhower said "I'm quite positive we must give the order. I don't like it but there it is. I don't see how we can possibly do anything else"; but it was to be confirmed at a last early-morning conference.
Monday 5 June
Eisenhower wrote of "wind of almost hurricane proportions shaking and shuddering his Sharpener camp (and) it seemed impossible that in such conditions there was any reason for even discussing the situation." At four in the morning the final go/no go conference was held. Stagg told them "Some good news. Gentleman, no substantial change has taken place since last time, but as I see it, the little has changed is in the direction of optimism ... as the predicted good weather should last until tomorrow, with good visibility and winds not more than Force 4." Ramsay noted 'this time the prophets came in smiling, and Hogben mused "I was scared of getting it wrong ... we knew we were making history".
Eisenhower's three commanders Ramsay, Leigh-Mallory and Montgomery all advised "Go". Montgomery and Major General Walter Bedell Smith, Eisenhower's chief of staff, were eager to launch the invasion. Admiral Bertram Ramsay was prepared to commit his ships, while Air Chief Marshal Trafford Leigh-Mallory expressed concern that the conditions would be unfavourable for Allied aircraft. After much discussion and considering in silence for some minutes; at 4:15 am Eisenhower said "OK, We'll go".The room filled with cheering and Stagg thinks they "look like new men. It was a marvel to behold." After a few questions to Stagg they dispersed, and Stagg headed for his tent in the Southwick House grounds to get some sleep.
At mid-day Eisenhower was playing a game of draughts in his trailer with his aide Harry Butcher; he was losing, but at 12:30 pm he managed a draw, which he saw as a good omen. Eisenhower and Admiral Creasy went to Stagg's office at 4:00 pm; concerned that the sky is still cloudy and the wind is still up. Stagg says reassuringly "they are coming along, sir; there'll be good breaks in the cloud by dark tonight and reduced winds." He showed Eisenhower the latest weather chart, and Eisenhower puts his hand on his shoulder and says "Good, Stagg: keep it up a little longer". At 9:00 pm (21:00) Stagg is relieved to see breaks in the cloud overhead; his prediction seems to be coming true. At 9am he confirms the 4:15am forecast to Bull.
The second coded messages over the BBC's Radio Londres from 21:15 warned the French Resistance that the invasion would start in 24 to 48 hours; a message to begin sabotage operations. Many messages (about 270) were sent out, including the famous line from Paul Verlaine's poem Chanson d'automne Blessent mon Coeur / d'une longeur / monotone, or Wound my heart with a monotonous languor. The Verlaine message (intercepted at 9:33 pm) went to OKW in Berchtesgaden, but stopped on Jodl's desk; he distrusted the source (Helmut Meyer at 15th Army HQ in France) and did not send out a general alert. Speidel at Rommel's headquarters was also told by the Operations desk that von Salmuth has put Fifteenth Army on alert, but Spiedel said to Staubwasser to call OB West and to "go with what they say"; Operations Officer there Bodo Zimmermann said that because of the weather Seventh Army in need not be alerted, so the army defending Normandy was not alerted.
At German Seventh Army headquarters Max Pemsel sent a message that officers going to a "Kriegspiel" (wargame) at Rennes should not leave for Rennes before dawn on 6 June, as there would be evidence of a landing before daylight. Von Rundstedt in Paris thinks that there is no immediate prospect for the "Grossinvasion" and at 10 pm when General Blumentritt tells him that Fifteenth Army Intelligence (now under the SS) has received the second line of the Verlaine poem, he said that Eisenhower would not announce the invasion over the BBC and to pass it onto OKW and to Blaskowitz but not to order a general alert of the two armies along the coast: "No, especially not in this weather".
Bodo Zimmermann at OB West distrusts the BBC message when told by an "agitated" Major Doertenback at 9:30 pm but shortly when Major Brink says that Colonel Reile has recently intercepted other trigger messages he decides to act, calling von Rundstedt who authorises a warning message to all commands (not an alert), saying Heeresgruppe B should go to Alarmstufe II and other commands are to increase their vigilance. In Cherbourg Admiral Hennecke has been told of foul weather for several days but about 11:30 pm he was told of heavy air raids and news about ten minutes later of 50 or 60 twin-engined aircraft approaching the Cherbourg Peninsula he breaks up the musical evening they are attending. The German Navy had cancelled its usual patrol and minelaying operations for the night of 5–6 June. Allied planners had assumed that the landing force departure would be known to the enemy by at least H-12 (twelve hours before to the first scheduled landing) and its destination clear to them by H-4; but this did not occur, partly due to the weather.
Churchill sent a message to the impatient Stalin: "Eisenhower forced to postpone for one day but the weather forecast has undergone a most favourable change and tonight we go" Stalin had been told in November that the invasion would take place by 1 May; and had mocked the plans to Milovan Djilas on 5 June, saying that it would be called off "if there's fog in the Channel".
Tuesday 6 June
Airborne troops took off shortly before midnight. Pathfinders jumped at 00:10 to mark landing zones, and Horsa gliders landed from 00:15 as part of Operation Tonga, which was to capture the Pegasus and Horsa bridges over the Caen Canal and Orne River.
American troops started landing on the French coast at H-Hour or 6:30 am; Utah Beach from 6:31 and Omaha Beach from 6:35. British troops landed on Gold and Sword Beaches at 7:25. Canadian troops landed on Juno Beach at 7:45, delayed from 7.35 by heavy swell and poor visibility; the amphibious tanks arrived 15 minutes after the infantry. The infantry landings were completed by 9pm (21:00), with 34,000 men ashore.
The BBC announced that Allied Armies have started landing "on the northern coast of France" at 9:32 am, Read by John Snagge, the actual location was not given. The sun rose at 5:58 and set at 22:07, with a full moon and heavy clouds across the Cotentin Peninsula, but later the low cloud lifted. Winds reached force 5 (22 mph/35 km/h) but by day's end were force 4 (16 mph/26 km/h). When the sun rose the sky was grey, but by late morning sunny spells appeared and the temperature reached 15 °C.
Aftermath
Had Eisenhower postponed the invasion, the next available period with the right combination of tides (but without the desirable full moon for airborne troops) was two weeks later, from 18 to 20 June. But during the second window a major storm, a "one in forty years event" would have made the landings impossible. A depression pushing north from the Mediterranean met a cold front sweeping south-east from Iceland, causing a devastating storm lasting four days between 19 and 22 June, and of only slightly less ferocity than the February 1905 storm on the Calvados coast. Hogben stated "On 17 June, all six of us produced a forecast for the nineteenth for almost perfect conditions (but the invasion) would have been a complete catastrophe." Waiting until July was "too bitter to contemplate". They would have had to return the troops on the ships back to their bases in England (and probably isolate them). The damage done to the US Mulberry harbour showed the power of the storm.
Eisenhower said when visiting Bradley on 20 July that "When I die they can hold my body for a rainy day and bury me during a thunderstorm for this weather will be the death of me yet"; France was experiencing torrential rain plus mist and low clouds blanketing Normandy for several days, causing seemingly endless postponements.
Weather data
Stagg and the teams based the forecast weather improvements for June 6 on reports from a single weather ship 600 miles (1100 km) west of Ireland reporting a rising barometer, and a lighthouse keeper on the Blacksod Lighthouse in County Mayo in neutral northwest Ireland. Under a secret 1939 deal between Dublin and the Met Office in Dunstable, lighthouse keeper Ted Sweeney phoned on 4 June "heavy rain and drizzle cleared, cloud at nine hundred feet and visibility on land and sea very clear". He was asked to confirm immediately and also an hour later; he never realised that they were checking the weather for the invasion. On 2 June Sweeney had reported bad weather; a rapidly falling barometer and a Force Six wind. Hogben wrote: "We used data gathered from special recce (reconnaissance) flights, ship observations, UK weather sites and pinched what we could from the Germans – once we broke their weather codes – and redrew our charts every few hours. None of us were operating with any of the technology and equipment that our successors today take for granted, such as satellites, weather radar, computer modelling and instant communications, and predicting conditions more than a day or two in advance was hazardous. All we knew was that there were several storms blowing across the Atlantic towards us, any one of which would have whipped up the waters where the fleet was gathering, and provided unwelcome cloud over Normandy". There is evidence that the USAAF team telephoned the Met Office team to change their initial unfavourable forecast for the 5th, but they demurred. Hogben and the other forecasters later received the Bronze Star.
In 2020, Maureen Flavin Sweeney was acknowledged by the United States government for her role in weather forecasting from Blacksod which directly influenced the schedule of the operation. Sweeney's weather report from the 3 June 1944 showing rapidly decreasing pressure, led to the delay of the landings by 24 hours by Eisenhower. This was credited with saving the lives of numerous soldiers during the landing. Unbeknownst to Sweeney, the hourly weather reports she sent to the Irish Met Service from the post office she worked as an assistant were forwarded to Allied Expeditionary Force in England. Sweeney was contacted directly by someone from England to confirm the reported readings. She was presented with a special US House of Representatives honour in June 2020. Sweeney went onto marry the lighthouse keeper, Ted, and only became aware of their involvement in the delay of the landings in 1956.
German forecasters
In 1961 while going to his inauguration JFK asked Eisenhower what gave him the edge on D-Day; he replied "Because we had better meteorologists (or weather forecasters) than the Germans."
Allied control of the Atlantic meant that German meteorologists did not have access to as much information as the Allies on incoming weather patterns. As the Luftwaffe meteorological centre in Paris predicted two weeks of stormy weather, many Wehrmacht commanders left their posts to attend war games in Rennes, and men in many units were given leave. Marshal Erwin Rommel returned to Germany for his wife's birthday, and to meet Hitler to try to get more Panzers.
When Rommel consulted meteorologist Major Heinz Lettau at Army Group B he was advised that there could be no invasion in the next two weeks because of the weather. However some German forecasters had foreseen poor conditions on 4 and 5 June but moderating on 6 June. The forecast of Professor Werner Schwerdtfeger of the Luftwaffe centre at Potsdam for D-Day of "prevailing winds of Beaufort Force five, varying between four and six" was similar to Stagg's. They expected Allied landings at or near high tide to minimise the "killing zone" or before dawn under cover of darkness; so a full moon featured less in their calculations, and they thought that Allies would not risk landing in winds worse than Force three (8–12 mph or 13–19 km/h). But Ramsay accepted Force four winds (13–18 mph or 21–29 km/h), and had on 4 June labelled worse sea conditions "unpromising but not prohibitive". And OB West and the Luftwaffe used tides for the Pas-de-Calais rather than the different tides for Normandy. German maritime patrols out of Cherbourg had been cancelled because of the weather.
Professor Walter Stube the Luftwaffe meteorologist in Paris no longer got Atlantic weather data from Jan Mayen Land, Sabin Island in Greenland and Spitsbergen, so he was depended on information from Luftwaffe pilots returning from missions at sea. He had noticed that previous Allied invasions e.g. Italy required a guarantee of fine weather. He discussed by phone on the 4th with meteorologist Major Hermann Mueller at von Runstedt's headquarters in Paris who had data suggesting that an airborne operation would be possible and a seaborne landing conceivable although Channel conditions were far from ideal. But they agreed that an imminent landing was most unlikely, although Mueller would review later that day when later data was received from Le Havre. Rommel also agreed, and wondered why the Allies had not used the three periods of fine weather in May. So he decided to leave for Germany that morning. However Erich Marcks had said on 2 June that "If I know the British ... they'll go to church next Sunday for one last time, and come Monday (i.e. 5 June). After Tuesday they won't have another chance for the tides until June 28–29". He also expected the landings to be at Normandy rather than Calais (von Runstedt) or the Somme estuary (Rommel).
See also
Weather events during wars
Pressure, a 2014 play set in Southwick House, about the events before D-Day
Verlaine Message Museum (in Tourcoing, France)
Notes
References
Citations
Works cited
Further reading
1944 in France
1944 in England
1944 in science
June 1944
Naval meteorology
Operation Overlord
Weather forecasting
Weather prediction
1944 in military history | Weather forecasting for Operation Overlord | [
"Physics"
] | 6,217 | [
"Weather",
"Weather prediction",
"Physical phenomena"
] |
68,444,148 | https://en.wikipedia.org/wiki/Walther%20graph | In the mathematical field of graph theory, the Walther graph, also called the Tutte fragment, is a planar bipartite graph with 25 vertices and 31 edges named after Hansjoachim Walther. It has chromatic index 3, girth 3 and diameter 8.
If the single vertex of degree 1 whose neighbour has degree 3 is removed, the resulting graph has no Hamiltonian path. This property was used by Tutte when combining three Walther graphs to produce the Tutte graph, the first known counterexample to Tait's conjecture that every 3-regular polyhedron has a Hamiltonian cycle.
Algebraic properties
The Walther graph is an identity graph; its automorphism group is the trivial group.
The characteristic polynomial of the Walther graph is :
References
Individual graphs
Bipartite graphs
Planar graphs
Hamiltonian paths and cycles | Walther graph | [
"Mathematics"
] | 174 | [
"Graph theory stubs",
"Planar graphs",
"Graph theory",
"Mathematical relations",
"Planes (geometry)"
] |
68,444,579 | https://en.wikipedia.org/wiki/Takeuti%E2%80%93Feferman%E2%80%93Buchholz%20ordinal | In the mathematical fields of set theory and proof theory, the Takeuti–Feferman–Buchholz ordinal (TFBO) is a large countable ordinal, which acts as the limit of the range of Buchholz's psi function and Feferman's theta function. It was named by David Madore, after Gaisi Takeuti, Solomon Feferman and Wilfried Buchholz. It is written as using Buchholz's psi function, an ordinal collapsing function invented by Wilfried Buchholz, and in Feferman's theta function, an ordinal collapsing function invented by Solomon Feferman. It is the proof-theoretic ordinal of several formal theories:
, a subsystem of second-order arithmetic
-comprehension + transfinite induction
IDω, the system of ω-times iterated inductive definitions
Definition
Let represent the smallest uncountable ordinal with cardinality .
Let represent the th epsilon number, equal to the th fixed point of
Let represent Buchholz's psi function
References
Proof theory
Ordinal numbers
Set theory | Takeuti–Feferman–Buchholz ordinal | [
"Mathematics"
] | 240 | [
"Ordinal numbers",
"Set theory",
"Proof theory",
"Mathematical logic",
"Mathematical objects",
"Number stubs",
"Order theory",
"Numbers"
] |
68,444,639 | https://en.wikipedia.org/wiki/Indospicine | Indospicine is an amino acid not found in proteins, which occurs in Indigofera species. The chemical resembles arginine.
It is toxic to mammals and causes liver damage and abortion. Dogs are particularly sensitive to the toxic effect and can sicken or die after eating a grazing animal that has eaten Indigofera.
History
For years it was known that Indigofera spicata was toxic to cows, rabbits and sheep. Both leaves and seeds are poisonous. Leaves were shown to contain β-nitropropionic acid, which affected chickens, but it was not found in the seeds. M. P. Hegarty, and A. W. Pound performed experiments to isolate the toxin by examining its effect on mouse livers. They used absorption dialysis and paper chromatography to separate chemical components from seeds, focusing on strong bases. Ninhydrin revealed where the different chemicals were on the paper used for chromatography. Bands were cut out of the paper, the substances extracted and then tested on the mice. Only one band was hepatotoxic. The substance was crystallised as a hydrochoride. The hydrochloride melted between 131 and 134°C. (α) + 18°. The ratio of elements was established and a rough molecular weight. From the degradation products, the structure was determined.
Properties
Between pH 2 and 10.5 indospicine is an ion with a single positive charge. In stronger alkaline conditions, it decomposes to ammonia and an amide. In strong acid L-α-amino-pimelic acid is formed.
With ninhydrin, indospicine gives a purple colour. With nitroprusside-alkaline ferricyanide reagent a yellow colour is produced, indicating it is not a guanidine derivative.
References
Alpha-Amino acids
Toxic amino acids
Amidines | Indospicine | [
"Chemistry"
] | 390 | [
"Bases (chemistry)",
"Amidines",
"Functional groups"
] |
68,445,549 | https://en.wikipedia.org/wiki/Mizab%20al-Rahma | The Mīzāb al-Raḥma (, 'gutter of mercy'), also known as the Mīzāb al-Kaʿba ('gutter of the Kaʿba'), is a rain gutter projecting from the roof of the Kaʿba enabling rainwater to pour to the ground below.
Architecture
The roof of the Kaʿba is flat, but slopes gently down to the north-west corner. From this corner, the mīzāb juts out, conducting rainwater from the roof. The lip of the mīzāb has an appendage known as the "beard of the mīzāb". The ground below is paved with marble slabs and decorated with inlaid mosaic designs. The design of the mīzāb has changed over the years; the current form is golden. Its length is , which is included in the wall of the Kaaba, its cavity width is , the height of each side is , and its entry into the roof wall is .
A detailed description of the mīzāb around 1183–85 CE is offered by Ibn Jubayr:
The Mizab is on the top of the wall which overlooks the Hijr. It is of gilded copper and projects four cubits over the Hijr, its breadth being a span. This place under the waterspout is also considered as being a place where, by the favour of God Most High, prayers are answered. The Yemen corner is the same. The wall connecting this place with the Syrian corner is called al-Mustajar [The Place of Refuge]. Underneath the water-spout, and in the court of the Hijr near to the wall of the blessed House, is the tomb of Isma'il [Ishmael] - may God bless and preserve him. Its mark is a slab of green marble, almost oblong and in the form of a mihrab. Beside it is a round green slab of marble, and both [they are verde antico] are remarkable to look upon.
Role in worship
In his Kitāb Akhbār Makka, the ninth-century scholar al-Azraqī wrote with reference to the mīzāb that "anyone who performs the ṣalāt under the mat̲h̲ʿab becomes as pure as on the day when his mother bore him".
Ibn Jubayr offers a vivid account of worship at the mīzāb in 1183 CE:
One of the things that deserve to be confirmed and recorded for the blessings and favour of seeing and observing it is that on Friday the 19th of Jumada l-Ula, which was the 9th of September [1183], God raised from the sea a cloud which moved towards Damascus and rained heavily like an abundant fountain, according to the words of the Messenger of God--may God bless and preserve him. It came at the ending of the afternoon's prayers and with the evening of the same day, raining copiously. Men hastened to the Hijr and stood beneath the blessed water-spout, stripping off their clothes and meeting the water that flowed from it with their heads, their hands, and their mouths. They pressed round it in a throng, raising a great clamour, each one coveting for his body a share of the divine mercy. Their prayers went up, the tears of the contrite flowed, and you could hear nothing but the swell of voices in prayer and the sobs of the weeping. The women stood without the Hijr, watching with weeping eyes and humble hearts, wishing they could go to that spot. Some pilgrims listful of performing a meritorious act, and moved as well to pity, drenched their clothes in the blessed water and, going out to the women, wrung them into the hands of some of them. They took it and drank it and laved it over their faces and bodies.
History
The first Mīzāb that worked for the Kaʿba was that the Quraish made when building it before the Prophetic mission.
Then the Mīzāb of Abd Allah ibn al-Zubayr when he built the Kaʿba in 684 AD.
Then the Mīzāb of Al-Hajjaj ibn Yusuf, who rebuilt the Kaʿba in 692 AD.
Then the Mīzāb of Sheikh Abu al-Qasim Ramesht, which his slave reached after his death in 1142 AD.
Then the Mīzāb of Al-Muqtafi in 1146 AD.
Then the Mīzāb of Al-Nasir in 1279 AD.
Then the Mīzāb of Suleiman the Magnificent in 1551 AD.
Then the Mīzāb which was made from Egypt in 1554 AD.
Then the Mīzāb of The Ottoman Sultan Ahmed I Ibn Muhammad III in 1612 AD.
Then the Mīzāb of The Sultan Abdulmejid I in 1856 AD.
Then the Mīzāb, which was sent with Haji Rida Pasha in 1859 AD.
Then the Mīzāb of the reign of King Fahd bin Abdulaziz in 1997, when he replaced the old Mīzāb for the roof of the Ka'aba with a new one, stronger with the same specifications as the old one.
Further reading
Caїd Ben Chérif, Aux Villes Saintes de l’Islam (Paris, 1919), p. 75.
References
Kaaba
Stormwater management | Mizab al-Rahma | [
"Chemistry",
"Environmental_science"
] | 1,101 | [
"Water treatment",
"Stormwater management",
"Water pollution"
] |
68,445,623 | https://en.wikipedia.org/wiki/Retrieval%20Data%20Structure | In computer science, a retrieval data structure, also known as static function, is a space-efficient dictionary-like data type composed of a collection of (key, value) pairs that allows the following operations:
Construction from a collection of (key, value) pairs
Retrieve the value associated with the given key or anything if the key is not contained in the collection
Update the value associated with a key (optional)
They can also be thought of as a function for a universe and the set of keys where retrieve has to return for any value and an arbitrary value from otherwise.
In contrast to static functions, AMQ-filters support (probabilistic) membership queries and dictionaries additionally allow operations like listing keys or looking up the value associated with a key and returning some other symbol if the key is not contained.
As can be derived from the operations, this data structure does not need to store the keys at all and may actually use less space than would be needed for a simple list of the key value pairs. This makes it attractive in situations where the associated data is small (e.g. a few bits) compared to the keys because we can save a lot by reducing the space used by keys.
To give a simple example suppose video game names annotated with a boolean indicating whether the game contains a dog that can be petted are given. A static function built from this database can reproduce the associated flag for all names contained in the original set and an arbitrary one for other names. The size of this static function can be made to be only bits for a small which is obviously much less than any pair based representation.
Examples
A trivial example of a static function is a sorted list of the keys and values which implements all the above operations and many more.
However, the retrieve on a list is slow and we implement many unneeded operations that can be removed to allow optimizations.
Furthermore, we are even allowed to return junk if the queried key is not contained which we did not use at all.
Perfect hash functions
Another simple example to build a static function is using a perfect hash function: After building the PHF for our keys, store the corresponding values at the correct position for the key. As can be seen, this approach also allows updating the associated values, the keys have to be static. The correctness follows from the correctness of the perfect hash function. Using a minimum perfect hash function gives a big space improvement if the associated values are relatively small.
XOR-retrieval
Hashed filters can be categorized by their queries into OR, AND and XOR-filters. For example, the bloom filter is an AND-filter since it returns true for a membership query if all probed locations match. XOR filters work only for static retrievals and are the most promising for building them space efficiently. They are built by solving a linear system which ensures that a query for every key returns true.
Construction
Given a hash function that maps each key to a bitvector of length where all are linearly independent the following system of linear equations has a solution :
Therefore, the static function is given by and and the space usage is dominated by which is roughly bits per key for , the hash function is assumed to be small.
A retrieval for can be expressed as the bitwise XOR of the rows for all set bits of . Furthermore, fast queries require sparse , thus the problems that need to be solved for this method are finding a suitable hash function and still being able to solve the system of linear equations efficiently.
Ribbon retrieval
Using a sparse random matrix makes retrievals cache inefficient because they access most of in a random non local pattern. Ribbon retrieval improves on this by giving each a consecutive "ribbon" of width in which bits are set at random.
Using the properties of the matrix can be computed in expected time: Ribbon solving works by first sorting the rows by their starting position (e.g. counting sort). Then, a REM form can be constructed iteratively by performing row operations on rows strictly below the current row, eliminating all 1-entries in all columns below the first 1-entry of this row. Row operations do not produce any values outside of the ribbon and are very cheap since they only require an XOR of bits which can be done in time on a RAM. It can be shown that the expected amount of row operations is . Finally, the solution is obtained by backsubstitution.
Applications
Approximate membership
To build an approximate membership data structure use a fingerprinting function . Then build a static function on restricted to the domain of our keys .
Checking the membership of an element is done by evaluating with and returning true if the returned value equals .
If , returns the correct value and we return true.
Otherwise, returns a random value and we might give a wrong answer. The length of the hash allows controlling the false positive rate.
The performance of this data structure is exactly the performance of the underlying static function.
Perfect hash functions
A retrieval data structure can be used to construct a perfect hash function: First insert the keys into a cuckoo hash table with hash functions and buckets of size 1. Then, for every key store the index of the hash function that lead to a key's insertion into the hash table in a -bit retrieval data structure . The perfect hash function is given by .
References
Abstract data types
Associative arrays | Retrieval Data Structure | [
"Mathematics"
] | 1,093 | [
"Type theory",
"Mathematical structures",
"Abstract data types"
] |
68,445,647 | https://en.wikipedia.org/wiki/Positive%20element | In mathematics, an element of a *-algebra is called positive if it is the sum of elements of the form
Definition
Let be a *-algebra. An element is called positive if there are finitely many elements , so that This is also denoted by
The set of positive elements is denoted by
A special case from particular importance is the case where is a complete normed *-algebra, that satisfies the C*-identity (), which is called a C*-algebra.
Examples
The unit element of an unital *-algebra is positive.
For each element , the elements and are positive by
In case is a C*-algebra, the following holds:
Let be a normal element, then for every positive function which is continuous on the spectrum of the continuous functional calculus defines a positive element
Every projection, i.e. every element for which holds, is positive. For the spectrum of such an idempotent element, holds, as can be seen from the continuous functional
Criteria
Let be a C*-algebra and Then the following are equivalent:
For the spectrum holds and is a normal element.
There exists an element , such that
There exists a (unique) self-adjoint element such that
If is a unital *-algebra with unit element , then in addition the following statements are
for every and is a self-adjoint element.
for some and is a self-adjoint element.
Properties
In *-algebras
Let be a *-algebra. Then:
If is a positive element, then is self-adjoint.
The set of positive elements is a convex cone in the real vector space of the self-adjoint elements This means that holds for all and
If is a positive element, then is also positive for every element
For the linear span of the following holds: and
In C*-algebras
Let be a C*-algebra. Then:
Using the continuous functional calculus, for every and there is a uniquely determined that satisfies , i.e. a unique -th root. In particular, a square root exists for every positive element. Since for every the element is positive, this allows the definition of a unique absolute value:
For every real number there is a positive element for which holds for all The mapping is continuous. Negative values for are also possible for invertible elements
Products of commutative positive elements are also positive. So if holds for positive , then
Each element can be uniquely represented as a linear combination of four positive elements. To do this, is first decomposed into the self-adjoint real and imaginary parts and these are then decomposed into positive and negative parts using the continuous functional For it holds that , since
If both and are positive
If is a C*-subalgebra of , then
If is another C*-algebra and is a *-homomorphism from to , then
If are positive elements for which , they commutate and holds. Such elements are called orthogonal and one writes
Partial order
Let be a *-algebra. The property of being a positive element defines a translation invariant partial order on the set of self-adjoint elements If holds for , one writes or
This partial order fulfills the properties and for all with
If is a C*-algebra, the partial order also has the following properties for :
If holds, then is true for every For every that commutates with and even
If holds, then
If holds, then holds for all real numbers
If is invertible and holds, then is invertible and for the inverses
See also
Nonnegative matrix
Positive operator (Hilbert space)
Citations
References
Bibliography
English translation of
Abstract algebra
C*-algebras | Positive element | [
"Mathematics"
] | 751 | [
"Abstract algebra",
"Algebra"
] |
68,445,831 | https://en.wikipedia.org/wiki/Isotropic%20helicoid | In fluid dynamics, an isotropic helicoid is a shape that is helical, so it rotates as it moves through a fluid, and yet is isotropic, so that its rotation and drag are the same for all orientations of the particle. It was first proposed by Lord Kelvin in 1871, who described a specific geometry with twelve vanes placed around a sphere. As of 2021, such a phenomenon has yet to be proven by researchers.
References
Geometric shapes | Isotropic helicoid | [
"Mathematics"
] | 99 | [
"Geometric shapes",
"Mathematical objects",
"Geometric objects",
"Geometry",
"Geometry stubs"
] |
68,446,173 | https://en.wikipedia.org/wiki/Grating-coupled%20interferometry | Grating-coupled interferometry (GCI) is a biophysical characterization method mainly used in biochemistry and drug discovery for label-free analysis of molecular interactions. Similar to other optical methods such as surface plasmon resonance (SPR) or bio-layer interferometry (BLI), it is based on measuring refractive index changes within an evanescent field near a sensor surface. After immobilizing a target to the sensor surface, analyte molecules in solution which bind to that target cause a small increase in local refractive index. By monitoring these refractive changes over time characteristics such as kinetic rates and affinity constants of the analyte-target binding, or analyte concentrations, can be determined.
Explanation
GCI is based on phase-shifting waveguide interferometry. Light of the sensing arm of the interferometer is coupled into a monomode waveguide through a first grating, and undergoes a phase change until it reaches a second grating, depending on the local refractive index within the evanescent field (see image). The second grating is used for coupling in light of the reference arm of the interferometer, and interference created by the superposition of the sensing and reference waves after the second grating translates the phase changes into an intensity modulation. By rapid phase modulation of one of the arms using a liquid crystal element, and thanks to the long interaction length with the sample, extremely high sensitivities with respect to surface refractive index can be achieved even at acquisition rates above 10 Hz. Since the interference is created on chip and not through free-space propagation, a high robustness with respect to ambient disturbances such as vibrations or temperature changes is achieved.
References
See also
Receptor–ligand kinetics
Affinity
Ligand binding assay
Immunoassay
Label-free quantification
Electromagnetism
Nanotechnology
Spectroscopy
Biochemistry methods
Biophysics
Forensic techniques
Protein–protein interaction assays
Plasmonics
Optical phenomena | Grating-coupled interferometry | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering",
"Biology"
] | 403 | [
"Physical phenomena",
"Protein–protein interaction assays",
"Surface science",
"Fundamental interactions",
"Nanotechnology",
"Spectroscopy",
"Plasmonics",
"Electromagnetism",
"Instrumental analysis",
"Materials science",
"Biophysics",
"Biochemistry methods",
"Molecular physics",
"Spectrum ... |
68,446,709 | https://en.wikipedia.org/wiki/Coulomb%20crystal | A Coulomb crystal (also Ion Coulomb crystal) is a collection of trapped ions confined in a crystal-like structure at low temperature. The structures represent an equilibrium between the repulsive Coulomb interaction between ions and the electric and magnetic fields used to confine the ions. Depending on the confinement techniques and parameters, as well as the number of ions in the trap, these can be 1-, 2- or 3-dimensional, with typical spacing between ions of ~10μm, which is significantly larger than typical solid-state crystal structures. Outside of ion traps, Coulomb crystals also occur naturally in celestial objects such as neutron stars.
Description
The magnitude of the Coulomb interaction F between two ions of charge q and Q a distance R apart is given by
directed along the axis between the two ions, where a positive value represents a repulsive force and vice versa.
Trapping techniques include variations on the Paul trap and Penning trap, where the former uses only electric fields while the latter also uses magnetic fields to confine the ions. Considering the simple case of two ions confined in a linear Paul trap, we have a radiofrequency oscillating field, which itself can confine a single ion in the (axial?) direction.
Experimental realisation
The typical process for creating ICCs in the lab involves ionisation of an elemental source, followed by confinement in an ion trap, where they are imaged via their fluorescence. Changing parameters such as the axial or radial confining potentials may lead to different observed geometries of the crystal, even if the number of ions does not change.
For measurements involving highly charged ions, these are typically observed as "dark" areas in the fluorescence of the Coulomb crystal, due to their different energy levels. This effect is also noticeable when ions in the Coulomb crystal appear to disappear, without changing the structure of the crystal, due to mixing with impurities in a non-ideal vacuum.
Heating effects are also important in the characterisation of Coulomb crystals, since thermal motion can cause the image to blur. This may be stimulated by the cooling laser being slightly off-resonance, and so needs to be carefully monitored.
Applications and properties
Coulomb crystals of various ionic species have applications across much of physics, for example, in high precision spectroscopy, quantum information processing and cavity QED.
References
Electrostatics
Ions
Particle traps | Coulomb crystal | [
"Physics",
"Chemistry"
] | 494 | [
"Ions",
"Molecular physics",
"Particle traps",
"Matter"
] |
68,447,213 | https://en.wikipedia.org/wiki/Adriana%20Cristina%20Serquis | Adriana Cristina Serquis (born 7 November 1967) is an Argentine physicist, the president of the National Atomic Energy Commission (CNEA), and principal researcher of the National Scientific and Technical Research Council (CONICET). In 2014, she received the L'Oréal-UNESCO National Award For Women in Science for her contribution to the rational use of electrical energy.
Biography
Adriana Cristina Serquis was born in Buenos Aires on 7 November 1967. She took an interest in physics at an early age.
She earned a licentiate in physical sciences at the Faculty of Exact and Natural Sciences of the University of Buenos Aires in 1993, and a doctorate in physical sciences at the Balseiro Institute in 2000.
From 1994 to 2000, she was a fellow of the CNEA and CONICET. From 2001 to 2003, she was a post-doctoral researcher at Los Alamos National Laboratory in the United States.
As CONICET's principal researcher at the CNEA's Bariloche Atomic Center, her line of research was framed in developing advanced techniques for characterizing materials for clean energies, where she studied the synthesis and characterization of superconducting materials and nanometric oxides for high temperature fuel cells.
She also served as an adjunct professor at the Andean Headquarters of the National University of Río Negro, dictating materials for the chemistry program, and as a visiting professor at the Balseiro Institute.
She is president of the Argentine Crystallography Association and a member of the administrative council of the .
She was named president of the CNEA on 4 June 2021.
Awards
2006: Bernardo Houssay Young Researcher Award
2013: Merit Diploma in Nanotechnology from the Konex Foundation
2014: L'Oréal-UNESCO National Award For Women in Science
Selected publications
"Effect of lattice strain and defects on the superconductivity of MgB2", A Serquis, YT Zhu, EJ Peterson, JY Coulter, DE Peterson, FM Mueller, Applied Physics Letters 79 (2001), 4399–4401.
"Strongly enhanced current densities in superconducting coated conductors of YBa2Cu3O7–δ+ BaZrO3", JL MacManus-Driscoll, SR Foltyn, QX Jia, H Wang, A Serquis, L Civale, Nature Materials 3 (2004), 439–443.
"High performance nanostructured IT-SOFC cathodes prepared by novel chemical method", L. Baqué, A. Caneiro, M. S. Moreno, A. Serquis, Electroch. Comm. 10 (2008) 1905.
"Vertically aligned nanocomposite thin films as a cathode-electrolyte interface layer for thin film solid oxide fuel cells", S.M. Cho, J.S. Yoon, J.H. Kim, Z.X. Bi, A. Serquis, X.H. Zhang, A. Manthiram, and H.Y. Wang, Advanced Functional Materials 19 (2009) 3868–3873.
"Synthesis and structural characterization of Co-doped lanthanum strontium titanates", F. Napolitano, D. G. Lamas, A. Soldati, A. Serquis, IJHE 37 (2012) 18302–18309.
References
External links
Adriana Serquis at the Bariloche Atomic Center
1967 births
21st-century Argentine physicists
Argentine nuclear physicists
Argentine women physicists
Living people
Los Alamos National Laboratory personnel
Academic staff of the National University of Río Negro
Nanotechnologists
Scientists from Buenos Aires
University of Buenos Aires alumni | Adriana Cristina Serquis | [
"Materials_science"
] | 762 | [
"Nanotechnology",
"Nanotechnologists"
] |
74,313,930 | https://en.wikipedia.org/wiki/Artificial%20intelligence%20content%20detection | Artificial intelligence detection software aims to determine whether some content (text, image, video or audio) was generated using artificial intelligence (AI).
However, the reliability of such software is a topic of debate, and there are concerns about the potential misapplication of AI detection software by educators.
Accuracy issues
Multiple AI detection tools have been demonstrated to be unreliable in terms of accurately and comprehensively detecting AI-generated text. In a study conducted by Weber-Wulff et al., and published in 2023, researchers evaluated 14 detection tools including Turnitin and GPT Zero, and found that "all scored below 80% of accuracy and only 5 over 70%."
Text detection
For text, this is usually done to prevent alleged plagiarism, often by detecting repetition of words as telltale signs that a text was AI-generated (including AI hallucinations). They are often used by teachers marking their students, usually on an ad hoc basis. Following the release of ChatGPT and similar AI text generative software, many educational establishments have issued policies against the use of AI by students. AI text detection software is also used by those assessing job applicants, as well as online search engines.
Current detectors may sometimes be unreliable and have incorrectly marked work by humans as originating from AI while failing to detect AI-generated work in other instances. MIT Technology Review said that the technology "struggled to pick up ChatGPT-generated text that had been slightly rearranged by humans and obfuscated by a paraphrasing tool". AI text detection software has also been shown to discriminate against non-native speakers of English.
Two students from the University of California, Davis, were referred to the university's Office of Student Success and Judicial Affairs (OSSJA) after their professors scanned their essays with positive results; the first with an AI detector called GPTZero, and the second with an AI detector integration in Turnitin. However, following media coverage, and a thorough investigation, the students were cleared of any wrongdoing.
In April 2023, Cambridge University and other members of the Russell Group of universities in the United Kingdom opted out of Turnitin's AI text detection tool, after expressing concerns it was unreliable. The University of Texas at Austin opted out of the system six months later.
In May 2023, a professor at Texas A&M University–Commerce used ChatGPT to detect whether his students' content was written by it, which ChatGPT said was the case. As such, he threatened to fail the class despite ChatGPT not being able to detect AI-generated writing. No students were prevented from graduating because of the issue, and all but one student (who admitted to using the software) were exonerated from accusations of having used ChatGPT in their content.
An article by Thomas Germain, published on Gizmodo in June 2024, reported job losses among freelance writers and journalists due to AI text detection software mistakenly classifying their work as AI-generated.
To improve the reliability of AI text detection, researchers have explored digital watermarking techniques. A 2023 paper titled "A Watermark for Large Language Models" presents a method to embed imperceptible watermarks into text generated by large language models (LLMs). This watermarking approach allows content to be flagged as AI-generated with a high level of accuracy, even when text is slightly paraphrased or modified. The technique is designed to be subtle and hard to detect for casual readers, thereby preserving readability, while providing a detectable signal for those employing specialized tools. However, while promising, watermarking faces challenges in remaining robust under adversarial transformations and ensuring compatibility across different LLMs.
Anti text detection
There is software available designed to bypass AI text detection.
A study published in August 2023 analyzed 20 abstracts from papers published in the Eye Journal, which were then paraphrased using GPT-4.0. The AI-paraphrased abstracts were examined for plagiarism using QueText and for AI-generated content using Originality.AI. The texts were then re-processed through an adversarial software called Undetectable.ai in order to reduce the AI-detection scores. The study found that the AI detection tool, Originality.AI, identified text generated by GPT-4 with a mean accuracy of 91.3%. However, after reprocessing by Undetectable.ai, the detection accuracy of Originality.ai dropped to a mean accuracy of 27.8%.
Some experts also believe that techniques like digital watermarking are ineffective because they can be removed or added to trigger false positives. "A Watermark for Large Language Models" paper by Kirchenbauer et al. also addresses potential vulnerabilities of watermarking techniques. The authors outline a range of adversarial tactics, including text insertion, deletion, and substitution attacks, that could be used to bypass watermark detection. These attacks vary in complexity, from simple paraphrasing to more sophisticated approaches involving tokenization and homoglyph alterations. The study highlights the challenge of maintaining watermark robustness against attackers who may employ automated paraphrasing tools or even specific language model replacements to alter text spans iteratively while retaining semantic similarity. Experimental results show that although such attacks can degrade watermark strength, they also come at the cost of text quality and increased computational resources.
Multilingual text detection
One shortcoming of most AI content detection software is their inability to identify AI-generated text in any language. Large language models (LLMs) like ChatGPT, Claude, and Gemini can write in different languages, but traditional AI text detection tools have primarily been trained in English and a few other widely spoken languages, such as French and Spanish. Fewer AI detection solutions can detect AI-generated text in languages like Farsi, Arabic, or Hindi.
Image, video, and audio detection
Several purported AI image detection software exist, to detect AI-generated images (for example, those originating from Midjourney or DALL-E). They are not completely reliable.
Others claim to identify video and audio deepfakes, but this technology is also not fully reliable yet either.
Despite debate around the efficacy of watermarking, Google DeepMind is actively developing a detection software called SynthID, which works by inserting a digital watermark that is invisible to the human eye into the pixels of an image.
See also
AI alignment
Artificial intelligence and elections
Content similarity detection
Hallucination (artificial intelligence)
Natural language processing
References
Artificial intelligence
Cybernetics
Computational linguistics
Computational neuroscience
Computational fields of study
Data science
Educational assessment and evaluation
Formal sciences
Natural language processing
Speech recognition
Unsolved problems in computer science
Plagiarism detectors | Artificial intelligence content detection | [
"Mathematics",
"Technology"
] | 1,394 | [
"Unsolved problems in mathematics",
"Computational fields of study",
"Unsolved problems in computer science",
"Computational linguistics",
"Natural language processing",
"Computing and society",
"Natural language and computing",
"Mathematical problems"
] |
74,314,161 | https://en.wikipedia.org/wiki/Hassium%20tetroxide | Hassium tetroxide (also hassium(VIII) oxide) is the inorganic compound with the formula HsO4. It is the highest oxide of hassium, a transactinide transition metal. It has little use outside of scientific interest, where it is often studied in comparison to osmium tetroxide and ruthenium tetroxide, its lighter octavalent group 8 element analogs.
Physical properties
Because of the extreme cost and difficulty of producing hassium, hassium tetroxide has never been obtained in macroscopic amounts, as only a few molecules have ever been synthesized. As a result, many of its physical properties are experimentally uncharacterized and unknown. However, most research available generally shows hassium tetroxide to behave like a typical congener to osmium tetroxide. Hassium tetroxide is less volatile than osmium tetroxide.
Synthesis
Hassium tetroxide can be obtained by reacting atomic hassium with oxygen at 600 °C.
Reactions
Hassium tetroxide can be combined with sodium hydroxide in an acid-base reaction, in which case it acts like the acid, to form sodium hassate(VIII):
References
Sources
Oxides
Hassium | Hassium tetroxide | [
"Chemistry"
] | 260 | [
"Oxides",
"Salts"
] |
74,315,363 | https://en.wikipedia.org/wiki/Drought%20in%20Nigeria | Long-term drought in Nigeria has resulted in desertification and a shortage of land for raising cattle and growing crops. To obtain land for farming or grazing, farmers and herdsmen are encouraged to go to new areas, which frequently leads to violence Herdsmen and farmers have been engaged in increasingly violent fights over the previous two years. More than 2,000 people lost their lives in 2018. However, many residents of the villages in Nigeria's Plateau State are unwilling to leave because they consider the region to be their home. When a community is burned down, new bricks are created to repair the destroyed homes.
Analysis of the orbital photographs from the National Aeronautics and Space Administration (NASA) shows that about 900,000 km2 of former savanna grassland in the region of Africa has been severely decertified between the early 1960s and 1986 due to persistent drought occurrences (O'Connor 1995).
Drought is a phenomenon that occurs in Nigeria and impacts the whole nation. The arid and semiarid regions are more sensitive than the dryer south, but the degree of vulnerability varies. In Northern Nigeria, there are several records of drought occurrences that resulted in famines in the years 1914, 1924, 1935, 1943, 1951–1954, 1972–1973, Mortimore 1989 and 1991–1995 (Tarhule and Woo 1997).
A recent survey conducted in seven states of Nigeria by SBMIntel, an Africa-focused research firm, showed that approximately 79% of Nigerian farmers were impacted by the damaging effects of drought and flooding in 2020. Among them, 26.3% experienced significant disruptions to their harvests due to extreme weather conditions. About 52.60% were somewhat affected, while 21.1% reported no impact from the drought and flooding. The survey, titled "Nigerians just want to eat," highlights the major challenges faced by Nigerian farmers and food transporters, which could potentially hinder national food security. It was published this month.
Effects
Drought has led to an increase in global climate change and the demand for sustainable development.
Drought has also led to deadly land grabs. In the past few years there have been a growing number of skirmishes between farmers and cattle herders searching for pasture and water.
The significant impact of drought in Northern Nigeria has been evident over the past years, affecting crops and farmers' produce in the region. Drought is characterized by prolonged absence or insufficient distribution of precipitation, resulting in a long-term deficiency of rainfall in a specific area. This situation leads to water stress and widespread crop failure when the rain fails to meet the evapo-transpiration demands of the crops.
Experts have labeled the 2022 floods in Nigeria as the most severe since 2012. These floods have devastated crops on more than 500,000 hectares of farmlands, affecting numerous smallholder and commercial farmers throughout the country.
Climate change affects Nigeria's hydro power generation, as it leads to unpredictable rainfall and drought patterns, impacting water levels in dams like Kainji Dam. During drought, the hydro power output decreases, affecting national power distribution and disrupting industrial activities that rely on a stable power supply. Conversely, excessive rainfall due to climate change can result in severe flooding in neighboring communities.
States affected by droughts in Nigeria
The following states including Sokoto, Katsina, Zamfara, Kebbi, Jigawa and Kano in the north-west and Borno, Yobe, Gombe, Bauchi and Adamawa States in the north-eastern part of the country are mainly affected by droughts.
Climate
The Harmattan season which occurs between the end of November and the middle of March brings about drought in Nigeria. It sometimes creates big clouds of dust which can result in dust storms or sandstorms. The wind can increase fire risk and cause severe crop damage.
Government agency
The National Environmental (Desertification Control and Drought Mitigation) Regulations, 2011 play roles in the regulation of desertification in Nigeria. They also play important roles in sensitizing Nigerians about the causes and dangers of Decertification. They achieve this by encouraging Reforestation, Reseeding, Afforestation and conservation of areas under Desertification.
References
Deforestation in Nigeria
Plateau State
Environmental issues in Nigeria
Man-made disasters
Climate of Nigeria
Forestry in Nigeria
Forestry in Africa | Drought in Nigeria | [
"Biology"
] | 866 | [] |
74,315,578 | https://en.wikipedia.org/wiki/DNA%20Valley | DNA Valley (or DNA Alley) is a region in Maryland that serves as a biotechnology hub with a focus on genetic medicine. Roughly traced by Rockville, Frederick, and Baltimore, DNA Valley includes the innovation companies in the Maryland I-270 technology corridor, the various campuses of federal entities such as the FDA and NIH, as well as The University of Maryland, Johns Hopkins University, The Institute for Human Virology, and various laboratories with high biosafety levels such as Fort Detrick. Major DNA valley cities include: Baltimore, Columbia, Germantown, Silver Spring, Rockville, Bethesda, Gaithersburg, College Park, and Frederick. The counties that make up DNA valley are Montgomery County, Frederick County, Howard County, Baltimore County, Anne Arundel County, and Carroll County. According to the Bureau of Economic Analysis, these counties contributed a combined GDP of $310,407,270 in 2021, higher than several nations. Local business leaders like Jeff Galvin expect this figure to increase in step with the growth of the biotechnology sector.
DNA Valley is home to many of Maryland's biotechnology, pharmaceutical, and life science companies including AstraZeneca, BioNTech, GeneDx, Qiagen, American Gene Technologies, and GlaxoSmithKline. A defining feature of the region is its staggering concentration of scientists and doctors. According to New Scientist, "There are more MDs and PhDs per capita in a 10-mile radius of DC than anywhere else in the country".
Etymology
The name "DNA Valley" is championed by American Gene TechnologiesⓇ CEO, Jeff Galvin. Galvin came to Maryland and the life science industry after a successful career in Silicon Valley and immediately saw the similarities between the early days of the tech industry in Silicon Valley and the life science industry in Maryland. The earliest documented use of the name came from an article written by Alison George at New Scientist in 2004, as she recounted a cab ride where her driver referred to the D.C. area as "DNA Valley" because of the concentration of biotech companies in the area.
DNA valley is not an actual geographical valley and is instead named as such because of the similarities between the biotechnology and life science boom in Maryland and the tech boom that occurred in Silicon Valley in the 1970s and 1980s. Previous to the growth of the biotechnology industry, Maryland and the surrounding regions were predominantly focused on the seafood, agriculture, and logistics industries due to the abundant waterways available in the state.
History
Role of the NIH
The National Institutes of Health (NIH) have played a major role in the development of the life science industry boom in Maryland, and thus the creation of DNA Valley. The NIH originally moved its headquarters from the Old Naval Observatory to Bethesda, Maryland in 1938. In 1989, as part of the launch of the Human Genome Project, the National Center for Human Genome Research (now known as The National Human Genome Research Institute) was founded in Bethesda. This made Bethesda the national hub for genetic research as genetic researchers from around the country came to help sequence the human genome. This project, being one of the most influential scientific projects of the last century, planted the seeds for the eventual biotechnology hub that has formed in the area since. The infrastructure and attention to the industry that the NCHGR and the HGP brought to Maryland are what opened the door to the extensive cell and gene therapy industries that Maryland and DNA Valley are now home to.
The NHGRI is not the only NIH subsidiary that has led to DNA Valley becoming such a major life science hub. The NIH as a whole has fueled the biotech industry in Maryland as the research done at the federally funded facilities has resulted in new fields of research, new tools, and highly trained researchers that often remain in the area and create their own life science companies.
For example, the work done by Roscoe Brady, MD, PhD on viral vectors caught the attention of entrepreneur Jeff Galvin, inspiring him to found American Gene Technologies and pursue potential cures for diseases like HIV, PKU, and certain cancers.. The NIH also funds outside research in the area, which further allows for the industry to flourish as more companies want to be based near the NIH headquarters in Bethesda.
A variety of life science-related conferences are held annually at the NIH headquarters in Bethesda, such as workshops, trainings, and professional conferences, all of which not only bring attention and prestige to the life science industry in Maryland, but also result in a better trained and educated population in the area, allowing for the further success of the industry.
The NIH is not exclusively located in Bethesda and has a variety of campuses in Maryland. The Bayview Campus in Baltimore contains the research programs of the National Institute of Aging and the National Institute of Drug Abuse. The Frederick National Laboratory and Riverside Research Park are home to the National Cancer Institute, which includes the Center for Cancer Research. The widespread footprint of the NIH in Maryland directly correlates to the biotech boom that resulted in DNA Valley, as the highest concentrations of life science companies are located in the same locations of Rockville, Frederick, and Baltimore.
Rise of genetic medicine
The first speculation about the plausibility of introducing DNA sequences into patient's cells to cure diseases occurred in the 1960s. Then in 1972, Theodore Friedman and Richard Roblin published a paper in Science named "Gene Therapy for Human Genetic Diseases?", which detailed the possibility of inserting unmutated or healthy DNA to cure patients with genetic diseases. However, this paper also urged that the technology be furthered with caution as a result of the lack of understanding of the technology and its potential effects. They were primarily worried about the lack of knowledge about genetic recombination and gene regulation, lack of understanding about the relationship between genetic mutations and diseases, and the lack of understanding of the potential side effects of gene therapy.
For 18 years after that paper was published, further research was conducted to help limit the risks detailed by Theodore Friedman and Richard Roblin. Then in 1990, the first successful gene therapy trial was launched. A four-year-old girl named Ashanthi De Silva with severe combined immunodeficiency (SCID) was treated with gene therapy. Ashanthi was lacking the enzyme adenosine deaminase (ADA), which caused her T-cells to die, leaving her with little to no protection against infection. To treat this, Dr. W. French Anderson from the National Heart, Lung, and Blood Institute in Bethesda, Maryland, delivered the correct ADA gene, using a disabled virus, to white blood cells that had been removed from her body, and then injected the cells back into her body.
The rise of gene therapy was not easy as it suffered a major setback in 1999 with the trials at the University of Pennsylvania. During the trials, an 18-year-old named Jesse Gelsinger who had the genetic disease ornithine transcarbamylase deficiency, died from an immune response after being treated with a working gene carried by an adenovirus.
The early 2010s brought back the evolution of gene therapy as a potential cure to many different diseases. New delivery methods for the gene therapies were discovered, thus making the techniques significantly safer. Researchers also added enhancers and promoters, which allowed for better control of the gene as they could decide when and where it would be turned on and to what extent. These discoveries, along with others made during this period, allowed gene therapy to regain its momentum and move to the forefront of Medical Technology development. There was then a wave of approvals for gene therapy techniques from 2003 to 2012, including therapies for cancer, artery disease, and others. Since then, the rate of development and approval of gene therapies has increased, with the FDA expecting to approve between 10 and 20 gene therapies each year until 2025.
Economy
The D.C. / Maryland area has the second-highest rated life science hub in the United States, with Maryland alone providing 44,260 jobs in life science. Maryland life science businesses generated over $18.6 billion in 2018, paid over $4.9 billion in wages, with an average salary of $110,690. Maryland also boasted the 5th highest concentration of doctoral scientists and engineers and the highest STEM concentration in the country in 2022. Between 2017 and 2022, the life science research jobs increased by 19%, which was larger than the national growth rate of 16%, indicating a particular focus on the industry in Maryland.
The region has more than double the amount of federal research labs than any other state, partly due to the presence of the NIH headquarters in Bethesda, Maryland. Maryland also has the 11th lowest unemployment rate at 2.5% in 2023, which is partly a result of the booming biotech and life science industry in the area.
Housing
Maryland, and by association DNA Valley, has a severe affordable housing shortage, with only approximately 30 affordable and available rental units for every 100 extremely low income families and a total housing shortage of 120,000 units. This is possibly due to the boom in life science jobs in the area, while the creation of housing units has remained constant, leading to the imbalance. DNA Valley also includes some of the highest cost of living areas in the country, with D.C. having the second highest and Maryland having the sixth highest.
Notable companies
Thousands of life science companies are headquartered in DNA Valley. The following are some of the notable companies based in the area:
Demographics
Depending on what geographic regions (particularly parts of Washington, D.C.) are included in the meaning of the term, the population of DNA Valley is between 2 million and 3.5 million. According to the U.S. Census Bureau, almost a third of DNA Valley's population is Black or of African descent, 11% are of Hispanic descent and 6.9% is of Asian descent.
Diversity
DNA Valley is one of the most diverse areas in the country, with 3 of the 10 most diverse communities in the area, those being Gaithersburg, Germantown, and Silver Spring. Biotechnology as a whole is not a typically diverse field, being overwhelmingly dominated by white (56%) and Asian (21%) employees. Even greater disparity is seen among executives, with 72% of execs being White and 15% being Asian. The biotech hub in DNA Valley tends to differ from this norm, likely due to the diversity of the area.
Gender
Similarly to race, gender disparity is quite significant in the field of biotechnology, with males dominating the space, particularly in positions of power. 66% of executives and 79% of CEOs are men. DNA Valley follows this trend, as in 2021, women only made up around 22% of the executive positions at biotechnology companies. One possible explanation for this, as proposed by Harvard Senior Research Associate Vivek Wadhwa, is that parents tend to not encourage their daughters to pursue a career in science and engineering as much as they would with their sons. Wadhwa also cites the lack of potential role models for women in the science and engineering fields in comparison to men.
However, interestingly, Maryland has the highest average salary for female CEOS, at around $280,000, which may be in part due to the higher average salaries in Maryland in general. Washington D.C. also has the second-highest female CEO percentage in the country at 47.5%, which would change the DNA Valley numbers depending on whether you include D.C. in the geographical boundaries of the region.
There have been concerted efforts to fix the current lack of females in Maryland life science fields, including the founding of a Women in Bio (WIB) chapter in the D.C. region in 2011. The focus of this chapter is to promote diversity and inclusion for all women in life science-related fields. WIB also sponsors the Herstory Gala, in Rockville, Maryland every year to celebrate the women trailblazers in life sciences that have had an impact on the field in the DNA Valley area.
Statistics
Maryland, and thus DNA Valley, is considered one of the most diverse states in the country, based both on religious and ethnic group diversity. DNA Valley's population is made up of 32% Black, 7% Asian, 12% Hispanic or Latino, and 1% Native American people. In terms of religious affiliations, DNA Valley's population is divided into 69% Christian-based faiths (mostly made up of equal percentages of Evangelical Protestant, Mainline Protestant, Historically Black Protestant, and Catholic), 23% not affiliated with any faith, and 8% having non-Christian-based faiths, primarily made up of Jewish, Muslim, Buddhist, and Hindu faiths
Education
The funding for public schools in DNA Valley varies drastically depending on the area as a result of increased grants from private foundations in wealthier areas such as Montgomery County and particularly Bethesda. Less wealthy areas such as Garret County rely on state funding
See also
List of technology centers
List of life sciences
References
Biotechnology | DNA Valley | [
"Biology"
] | 2,674 | [
"Biotechnology",
"nan"
] |
74,316,081 | https://en.wikipedia.org/wiki/Leopardus%20narinensis | Leopardus narinensis, also called the red tigrina, Nariño cat, and Galeras cat by the scientists who discovered it, is a putative species of small wild cat in the genus Leopardus. It was described in 2023, based on a single skin collected in 1989.
Etymology
The specific epithet narinensis refers to the Nariño Department in southern Colombia, where the skin was collected. The proposed common names "Nariño cat" and "Galeras cat" also refer to where it was found (the Galeras volcano in the Nariño Department), while "red tigrina" refers to its markedly reddish coloring.
Taxonomy and phylogeny
The skin was first collected in 1989 and donated to a Colombian national institute, which later transferred its biological collections to the Alexander von Humboldt Biological Resources Research Institute, where it remained classified as an ocelot skin until 2001, when Manuel Ruiz-García noticed it while searching for jaguar and puma specimens. He recognized it as being a different species and, when other authorities on South American cats could not identify it, spent the next two decades researching the skin. The final paper was published in June of 2023.
The red tigrina is classified as a member of the genus Leopardus, the small spotted cats of South America.
A scientific paper published only two months later, in August 2023, considered the holotype of L. narinensis to be a specimen of L. tigrinus based on morphological comparison.
Phylogeny
Genetic analyses indicate that the Nariño cat diverged from other Leopardus species about 1.3–1.0 million years ago. Both its nuclear and mitochondrial DNA are noted to be different from every known species of cat. In those genetic tests, it was consistently recovered as a sister taxon to the kodkod-Geoffroy's cat clade.
Cladogram of L. narinensis position in the genus:
Characteristics
The Galeras cat is, like other tigrinas, a small spotted cat, but the base color of its fur is more reddish than in other tigrinas. The rosettes are black but with even more intensely red coloring on the inside. The top of the head and the dorsal crest are darker. The body is shorter and more robust, and the head is rounder and wider, the face flatter. The coat is denser and woollier.
Distribution and habitat
The holotype and only specimen was collected from the páramo of the Galeras volcano in southern Colombia, above sea level. The region has a high level of endemism due to isolation during the climatic changes at the end of the Pleistocene.
It has not been recorded by the camera traps that have been present in southern Colombia since 2018, and the species may already be nearly (or even totally) extinct.
References
External links
Leopardus
Felids of South America
Mammals described in 2023
Species known from a single specimen | Leopardus narinensis | [
"Biology"
] | 597 | [
"Individual organisms",
"Species known from a single specimen"
] |
74,317,371 | https://en.wikipedia.org/wiki/Neigh | A neigh () is the sound made by horses, horse hybrids such as the hinny, and other equines, such as the zebra. It consists of a succession of jerky sounds, initially high-pitched and gradually lower. Produced on exhalation by the larynx and modulated, it enables the animal to express its emotions (such as fear or satisfaction) and to inform other animals through the sound produced. The main function of neighing is to alert other equines to its presence in the absence of visual communication. However, horses rarely neigh.
Buffon established a classification of neighs into five categories, according to the emotion expressed by the horse, which has been widely used in subsequent works. Today, we only speak of neighing when the horse is vocalizing, and of squeaking or whinnying in other cases.
In literary works, the horse neigh is often the means by which it makes itself known to its rider and communicates with them. In divination practices, examination of the sound produced and the horse's attitude has given rise to hippomancy. Horse neigh plays a particularly important role in Tibetan Buddhist beliefs.
Etymology and terminology
In English and other Germanic languages, the Middle High German nēgen gave rise to the Old English hnǣgan and Middle English neyen, then the modern English verb ‘to neigh’. As in French, its use is attested before the 11th century. In the Tibetan language, gsaṅs refers to voice in a general sense, and skad-gsaṅs to neigh, i.e., literally, "the horse's voice". Tibetan dictionaries distinguish between two types of neighing, the one that resounds and the other one that becomes faint. In English, a similar distinction exists between nickering, whinnying and neighing, which designate three types of neighing. This terminological distinction does not exist in French.
In French, 'hennissement' is a masculine noun that, according to the Trésor de la langue Française informatisé, was attested in the 13th century and it is in the Histoire de l'empereur Henri de Constantinopled by Henry of Valenciennes (a text dated around 1220). 'Hennissement' is derived from the verb 'hennir', attested in 1100 for human beings, and 30 years later for the "cry of a horse", in Philippe de Thaon's Bestiaire. Moreover, 'hennir' is a borrowing from the Latin 'hinnire' which, as Quintilian notes in his Institutio Oratoria, is formed on an onomatopoeia of the "horse cry": the repetition of the vowel "i" evokes the sound of neighing. Other Romance verbs, such as the Italian 'nitrire', derive from it. An influence from Frankish 'kinni', meaning jaw, is also possible. The hinny neighs like a horse, while the mule bray like a donkey. In French, 'hennissement' and 'hennir''' are also used for the zebra.
History
From the earliest times humans have been aware of the sounds made by horses, which have been domesticated since antiquity, and has attributed all kinds of meanings to them. In Western Europe, Buffon's study of horses, in which he follows Cardan, describes five types of neighs. This study has been an authority for centuries, and it is included in Encyclopédie, ou dicctionnaire raisonné des sciences, des arts et de métiers, among others. According to him, these five horse neighs are used to express joy, desire, anger, fear and pain respectively. The five types of neighs are as follows:
the neigh of joy, in which the voice is heard for quite a long time, rising and ending on higher notes. The horse kicks at the same time, but lightly, and does not try to strike;
the neigh of desire, love and affection, in which the horse doesn't kick. It is heard for a long time, and the voice ends with lower, faster sounds;
the neigh of anger, during which the horse kicks and strikes dangerously, very short and high-pitched;
the neigh of fear, during which he also kicks, is hardly longer than that of anger. The voice is low, hoarse and seems to come entirely from the nostrils. This neigh is quite similar to the lion's roar; and
the neigh of pain, less a neigh than a whinny, which is low-pitched and follows breathing.
This classification, very popular and widely used, is no longer valid today.
According to some 19th-century encyclopedias, in some countries, particularly Hungary, it was customary to split the horse's nostrils to prevent neighing, particularly in times of war. This information is modified by the fact that neighing is modulated in the larynx. The splitting of a donkey's nostril to prevent braying is, however, well attested during the World War I.
Description
The neigh is a succession of jerky sounds, first high-pitched, then gradually lower, producing a sort of long "Hiiiihiiiihiii". Intensity and pitch can vary considerably. It can be so loud that it can be heard by the human ear from a distance of several kilometers, which means that horses, whose hearing is better developed, can hear it from an even greater distance. When a horse neighs, it opens its mouth, and its jaw and nostrils move. Neighing is more frequent in the entire horse than in the mare and gelding, and the timbre of their voices is not as strong. From birth, the male has a louder voice than the female. By the age of two or two-and-a-half, when puberty sets in, the voice of all horses becomes louder. The horse's vocalizations have complex sounds, a wide bandwidth and varied frequencies, making them richer than those of most domestic animals. Although the name "neigh" is generally applied to the horse's call, the hinny, a hybrid of stallion and donkey, readily neighs like a horse, while the mule, a hybrid of donkey and mare, is more likely to bray.
Mechanism
The horse neighs by inhaling to fill its lungs and then expelling the air that passes through its larynx. Neighing occurs in the larynx during exhalation, which is why horses with an open trachea are unable to neigh, as the air no longer passes through it. The other parts of the respiratory system contribute to neighing in a secondary way. The lungs expel air into the larynx. The pharynx and nasal cavities add power to the vocalization and modify it. The air expelled from the lungs pushes the lips away from the glottis, until the vocal cords return on themselves and momentarily close the respiratory tract, only to spread apart again, producing vibratory movements fast enough to give rise to sounds, much as happens when you blow into the reed of an oboe. The horse's throat, mouth and lips modify the nature of the sound emitted, while the power of the neigh is determined by the force with which air is expelled from the lungs.
Special features
The Haflinger breed, originally from the Tyrol in the Alps, is said by its breeders to have a wider range of neighs than other horses. This may be due to the fact that, in mountainous environments, horses have difficulty seeing each other and rely more on auditory communication.
Function and emotions
Neighing is one of the horse's means of communication, but far from the most widely used. Not resorting to neighing is a precaution against possible predators of this large herbivore, who might spot potential prey by the sound. Horses mainly use body language. They only resort to neighing in very specific cases, notably when they can't see other horses to decipher their movements. The primary function of neighing is to allow the animal to call other horses it can't see.
Horses use neighing a lot when they're young. When Przewalski's foals wake up, they neigh and receive a response from their mother, more rarely from another horse. They may try to locate the source of adult horses' neighing. The mare calls its foal by neighing if it wanders too far away, and the foal who is looking for its mother calls it in the same way: each probably recognizes the other's neigh very clearly.
Horse neighs are also a way for them to express their intentions, concerns and satisfactions, generally when these give rise to strong emotions, such as those experienced by two stallions fighting, or a stallion who senses and approaches a mare. There are differences depending on the sensations the animal feels and communicates. Researchers have studied the emotions that horses communicate to other horses when they neigh: while the tone is constant, the harmonics are varied and increase in proportion to anxiety. Frequency plays a role in communication.
Neigh of satisfaction
This neigh is rather low-pitched and soft. It's a sign of friendship, emitted mainly at mealtimes, and also by the mare to reassure its foal. According to English-speaking authors, this type of neighing is divided into two quite distinct types. Whinnying refers to the neigh of satisfaction, a form of recognition that expresses the horse's joy. Nickering is the mare's neigh to reassure its foal, but can also be emitted by horses in the presence of people they particularly like: the animal then expresses its satisfaction at being at the person's side. The first type of neigh is louder and higher-pitched than the second.
Neigh of worry and for calling
This neigh is much louder and higher-pitched, and can be heard from a great distance. It can be heard by a worried animal preparing to flee, or by a horse separated from its companions, looking for signs of other horses in the vicinity. The animal is waiting for a response that will provide the information it is seeking. This cry is easily recognizable, deafening a person standing next to the horse at the same time. What's more, the animal emitting it generally adopts a very specific position, raising its head to clear its throat, which increases the power of the sound produced. Brood mares often neigh to call their foals close to them when they stray too far.
Other sounds
Other sounds produced by the horse are not neighs, but squeaks of mirth or pain, or whinnies of suffering. The loudest squeak is also a threat: it indicates that the horse is about to express its anger physically, for example during a group feeding or when a mare pushes a stallion away.
In culture
As with all animals in human contact, the horse neigh can take on a variety of symbolic meanings. It plays a role in hippomancy, myths, tales, legends and popular texts. According to dream interpretations, neighing heralds news of a friend or a happy event to be celebrated among friends. In the visual arts, the rendering of a horse's neighing is particularly elaborate in Picasso's Guernica, in which the horse neigh is intended to convey the pain of an entire people. Films, especially westerns, frequently add recorded neighs to scenes with horses, which can give the false impression that the animal makes extensive use of this mode of communication.
Music
A frequent theme in modern Greek folk songs is that of the woman who hears a horse neigh and recognizes the cry of her husband's mount, but not the man she has just spent the night with, whom she believes to be her lover. The neighing acts as a catalyst, preceding the punishment of the adulterous wife. In other songs, the neighing may be a decoy, a love code, an instrument of recognition to identify the horse rider, or a tribute from the equine to its departed master. All these meanings testify to the deep relationship between man and horse.
Literature
In the Roman d'Alexandre, the fifteen-year-old future king passes the place where the terrible Bucephalus is confined one day and hears a loud neigh. When he asks which animal it belongs to, one of his father's men replies that Bucephalus is locked up there because it feeds on human flesh, making it very dangerous. When he hears Alexander's voice, Bucéphale lets out another neigh, this time very soft, and leans towards the young man he recognizes as his master.
One of the impressives of the Japanese language is that of a group of horses neighing to greet the departure or arrival of a person they recognize. In Ronsard's poem L'Ombre du cheval, the neighing gives a form of reality to an imaginary painting horse seen in a dream: the neighing awakens its master, becoming a clue to the animal's possible reality. Le vent du Nord set come le hennissement d'un Cheval noir is a 40-page story from the manga series Sabu to Ichi Torimono Hikae (1966-1972) by Shōtarō Ishinomori.
Beliefs, legends and divination
Neighing can be an indicator in hippomancy, divination using horses. As with coat characteristics and white markings, various popular beliefs attribute qualities to the horse's neighing. According to French belief in the mid-nineteenth century, horses that neigh most often, especially with joy and desire, are the best and most generous.
Buddhism and Hinduism
The horse neigh is a symbol of the wrathful Buddhist deity Hayagriva, whose head is surmounted by one to three green-necked neighing horses. This frightens Māra, Gautama buddha's tempting demon (as well as his avatars), and restores his faith in attaining enlightenment. Ash-Vagosha, whose name means "horse neigh", was a renowned Indian Buddhist of the 1st century, who wrote a biography of the Buddha. In Hinduism, thunder is created when Indra's chariot passes by, by the neighing of his horses.
Tibet
Various beliefs relating to neighs are particularly well documented in Tibet. According to the Tibetan hippologists who wrote the Touen-houang manuscripts (800-1035), a horse neigh sound comes from the wind, the force of life, from the base of its navel to its mouth. Depending on the sound and position of the horse when it neighs, it can be a good or bad omen for its master. Neighs that imitate the sound of a conch shell, large drum, lion, tiger, chariot roll, flute, bull, thunder or river; are signs of good fortune, especially if the animal lowers its head or turns it to the left when neighing. Similarly, a horse that neighs a lot when accompanying others, or makes others neigh, is a good sign. Conversely, if a horse neighs a lot while looking around, or if its cry resembles a donkey's bray, then it's a bad omen. A bad horse is one that imitates the cry of a camel, vulture, cat, jackal, dog, crow, monkey or owl. A horse that neighs when looking to the right or when touched, and is ridden by a king, promises its rider to rule the whole Earth. A sick horse, on the other hand, will soon die if it neighs while looking and breathing sideways. Finally, Tibetan hippologists recommend not to draw omens from very young, very old, sick, hungry or thirsty horses, but to pay close attention to neighing in all other cases.
Hippomancy in the West
Divination by means of neighing is also practiced in the West, but is less well documented. In his Dictionnaire Infernal, Collin de Plancy speaks of Celtic hippomancy, thanks to the neighing and movement of white horses fed and kept in consecrated forests, considered to be the guardians of divine secrets. In his Morales sur le livre de Job'', Pope Gregory I describes the horse as a true preacher, and its neigh as the voice of preaching. The myth of Balius and Xanthus, the horses of Achilles, one of which speaks and predicts the death of its master, provides some evidence of hippomancy through neighing.
Darius' horse
According to a legend recounted by Herodotus, the neighing of a horse plays a major role in the choice of government in ancient Persia. As seven conspirators were unable to agree on the preferable form of government, it was decided that they would all ride to the same place the next morning before sunrise, and that whoever's horse was first to neigh in greeting to the sun would be made King of the Persians. Darius' squire learns of this, and cheats by leading his master's stallion to a mare placed where he will be the next morning. When Darius' horse arrives before sunrise, the smell and memory of the previous day's mare cause him to neigh with joy, and the kingdom falls to his master. The six other conspirators dismount and proclaim Darius I king of the Persians. In reality, Darius was probably chosen by consensus among the conspirators, but this legend illustrates the importance of the horse's neigh in defining the future king.
See also
List of animal sounds
References
Bibliography
Onomatopoeia
Animal sounds | Neigh | [
"Biology"
] | 3,729 | [
"Ethology",
"Behavior",
"Animal sounds"
] |
74,317,822 | https://en.wikipedia.org/wiki/Jarek%20Gryz | Jarek Gryz is a computer scientist, data analyst, author, and academic. He is a professor in the Department of Electrical Engineering and Computer Science and a member of the Cognitive Science Program in the Department of Philosophy at York University in Toronto, Canada.
Gryz's research spans the field of data analysis, query optimization, artificial intelligence, and privacy in IT systems. He authored the book Database Query Optimization with Soft Constraints and has published over 100 peer-reviewed articles, He is the recipient of the Outstanding Contribution to Internationalization Award and the IBM Faculty Award as well as a Senior Member of the Institute of Electrical and Electronics Engineers (IEEE).
Education and early career
Gryz earned his MA degree in Philosophy from Warsaw University in 1989 and another MA degree in philosophy from the University of Maryland, College Park in 1992. He then shifted his subject of study and started a graduate program in the Department of Computer Science in 1993 and received a master's degree in computer science from the same institution in 1995. Subsequently, in 1996, he completed a brief internship at the Stanford Research Institute in Menlo Park, followed by a Ph.D. in computer science in 1997 under the supervision of Jack Minker, from the University of Maryland, College Park.
Career
Following his Ph.D., Gryz started his academic career as an Assistant Professor and became a professor at York University in Toronto. He has also held teaching appointments at Warsaw University in Poland, Reykjavik University in Iceland, and College of William and Marry in the United States In addition, he served as the Faculty Fellow of the IBM Centre of Advanced Studies in Canada from 1998 to 2013. He holds an appointment as a professor in the Department of Electrical Engineering and Computer Science and is a member of the Cognitive Science Program in the Department of Philosophy at York University in Toronto, Canada.
Research
Gryz's research has primarily focused on the field of database systems and has made contributions in various areas, including query optimization, data visualization, and data mining. Furthermore, he has explored the philosophical foundations of Artificial Intelligence.
Computer science
Gryz has worked primarily in the area of database query optimization. He proposed several techniques to improve query performance in relational databases using sampling, integrity constraints, views or a novel concept of soft constraints. Many of these algorithms have been implemented in the commercial version of DB2, IBM's relational database system. He further extended this work into other types of databases such as object-oriented, XML, and graph.
In the area of data mining, Gryz designed new algorithms for discovery of homogeneous regions in a binary matrix. He also worked on improving existing methods of frequent itemset mining. Furthermore, he branched into research on data visualization, which serves as a crucial element of analysis of massive data sets.[17].
Philosophy
Gryz's early research in philosophy focused on ethics. He examined the distinction between deontic and aretaic terms in moral vocabulary and offered a new interpretation of Stoic ethics. His interest in philosophy led to interdisciplinary research into philosophical foundations of AI, privacy in IT systems, and ethical issues, such as bias and interpretability of algorithms.
Awards and honors
2006 – Faculty Award, International Business Machines Corporation
2010 – Outstanding Contribution to Internationalization Award, York International
2016 – Senior Member, Institute of Electrical and Electronics Engineers (IEEE)
Bibliography
Books
Database Query Optimization with Soft Constraints (2008)
Selected articles
Gryz, J. (1999). Query rewriting using views in the presence of functional and inclusion dependencies. Information Systems, 24(7), 597–612.
Edmonds, J., Gryz, J., Liang, D., & Miller, R. J. (2003). Mining for empty spaces in large data sets. Theoretical Computer Science, 296(3), 435–452.
Chomicki, J., Godfrey, P., Gryz, J., & Liang, D. (2003). Skyline with presorting. In Proceedings of ICDE, 717–719.
Godfrey, P., Shipley, R., & Gryz, J. (2007). Algorithms and analyses for maximal vector computation. The VLDB Journal, 16(1), 5–28.
Yakovets, N., Godfrey, P., & Gryz, J. (2016). Query planning for evaluating SPARQL property paths. In Proceedings of the 2016 International Conference on Management of Data (pp. 1875–1889).
Godfrey, P., Gryz, J., & Lasek, P. (2016). Interactive visualization of large data sets. IEEE transactions on knowledge and data engineering, 28(8), 2142–2157.
Gryz, J., & Rojszczak, M. (2021). Black box algorithms and the rights of individuals: No easy solution to the" explainability" problem. Internet Policy Review, 10(2), 1–24.
References
Computer scientists
Data scientists
University of Warsaw alumni
York University
University of Maryland, College Park faculty
Year of birth missing (living people)
Living people | Jarek Gryz | [
"Technology"
] | 1,055 | [
"Computer science",
"Computer scientists"
] |
74,318,528 | https://en.wikipedia.org/wiki/Ethics%20%26%20the%20Environment | Ethics & the Environment is an academic journal focussed on environmental ethics published by Indiana University Press with support from the Willson Center for Humanities and Arts, the Philosophy Department, and the Franklin College of Arts & Sciences at the University of Georgia. The journal was established in 1996 by Victoria Davion. It is now edited by Piers H. G. Stephens.
Abstracting and indexing
The journal is abstracted or indexed in the Emerging Sources Citation Index, EBSCOhost, Scopus, and ProQuest.
References
External links
Journal page at University of Georgia
Environmental ethics journals
Biannual journals
English-language journals
Indiana University Press academic journals
Academic journals established in 1996 | Ethics & the Environment | [
"Environmental_science"
] | 136 | [
"Environmental ethics journals",
"Environmental ethics",
"Environmental science journals",
"Environmental social science stubs",
"Environmental science journal stubs",
"Environmental social science"
] |
74,318,621 | https://en.wikipedia.org/wiki/Jim%20Ballantine%20%28chemist%29 | James A Ballantine CChem FRS (21 February 1934 – 30 April 2013) was a chemist and academic at Swansea University.
Life and career
Ballantine was born in England but grew up in Scotland, he studied chemistry at Liverpool University and went on to complete his PhD. He started his career under Professor George Kenner with an ICI Post-doctoral Fellowship working on the synthesis of unsymmetrical porphyrins. In 1961, Ballantine took up a lectureship in Organic Chemistry at Swansea University, becoming Reader in 1981. Ballantine was the director of the Institute of Marine Studies at Swansea University, which he established in 1978, and was also the founding director of both the Environmental Monitoring Unit and EPSRC National Mass Spectrometry Service Centre. He retired in 1998.
Ballantine was an active member of the Royal Society of Chemistry, and he served for 23 years as the Hon Secretary and Treasurer of the South Wales West Local Section as well as in 1995 together with Bill Williams they gave the Science and Energy lecture all over Wales on some 800 occasions to some 80,000 pupils.
References
Academics of Swansea University
Fellows of the Royal Society of Chemistry
British chemists
Mass spectrometrists
Alumni of the University of Liverpool
1934 births
2013 deaths | Jim Ballantine (chemist) | [
"Physics",
"Chemistry"
] | 258 | [
"Biochemists",
"Mass spectrometry",
"Spectrum (physical sciences)",
"Mass spectrometrists"
] |
74,321,022 | https://en.wikipedia.org/wiki/Katherine%20Borden | Katherine Borden PhD FRSC is a Canadian researcher of Molecular Biology and Biochemistry at Northwestern University in Chicago, USA after a long tenure at University of Montreal in Quebec, Canada. She has worked on finding new cancer treatments using pre-existing drugs,. She uses a combination of biochemistry, structural biology, cell biological, and clinical studies to study RNA processing. She has received many awards for this work including selected as a Stohlman Scholar of the Leukemia and Lymphoma Society USA (2005), Distinguished Scientist of the Canadian Society for Clinical Investigation (2011), CSMB Canadian Science Publishing Senior Investigator Award (2022) and was inducted as a fellow of the Royal Society of Canada in 2022 and as Fellow of the Canadian Academy of Health Sciences (2024).
Research
Her work provided a series of transformative revelations into the role of dysregulated RNA metabolism in cancer using the eukaryotic translation initiation factor eIF4E as an exemplar. Her studies demonstrated that dysregulation of this factor influenced multiple steps in RNA processing of thousands of RNAs simultaneously thereby reprogramming the cell to become more oncogenic. eIF4E impacts the extent of m7G RNA capping, splicing, export and/or translation of these RNAs based on the presence of cis-acting elements within the RNAs as well as induction of wide scale changes to the production of factors substantially modulated the RNA processing landscape within cells. Her work showed that modulating of many of these factors influence cell survival and cell motility contributing to cancer.
Her studies also led to the finding that a substantial number of Acute Myeloid Leukemia (AML) patients were characterized by elevated eIF4E. This coupled to the discovery that eiF4E could bind to and be inhibited by an antiviral drug ribavirin led to the first clinical trials targeting eIF4E in patients. Indeed, these were also the first studies to target RNA translation or RNA export (and likely related RNA processing events) in humans. Targeting of eIF4E was safe and corresponded to objective clinical responses including remissions in patients. These studies also led to the discovery of a new form of drug resistance in patients, inducible drug glucuronidation. Drug glucuronidation impacts 50% of drugs usually through liver mediated drug deactivation. However, this work revealed that cancer cells could turn on the enzymes involved in this process.
Her lab developed the means to target this inducible drug glucuronidation, with Vismodegib, and showed in patients this reduced levels of glucuronidation enzymes which corresponded to ribavirin activity, targeting of eIF4E and objective clinical responses. However, eventually patients become resistant to the Visomdegib and thus, new modalities are required to overcome this form of drug resistance long term.
References
External links
Living people
Year of birth missing (living people)
Yale University alumni | Katherine Borden | [
"Chemistry"
] | 616 | [
"Biochemistry stubs",
"Biochemists",
"Biochemist stubs"
] |
74,324,439 | https://en.wikipedia.org/wiki/Thermal%20equation%20of%20state%20of%20solids | In physics, the thermal equation of state is a mathematical expression of pressure P, temperature T, and, volume V. The thermal equation of state for ideal gases is the ideal gas law, expressed as (where R is the gas constant and n the amount of substance), while the thermal equation of state for solids is expressed as:
where is the volume dependence of pressure at room temperature (isothermal), and is the temperature dependence of pressure at constant volume (isochoric), known as thermal pressure.
For the ideal gas at high pressure-temperature (high P-T), the soft gas is filled in a solid firm container, and the gas is restrained inside the container; while for a solid at high P-T, a solid is loaded inside the soft medium, and the solid can expands/shrinks in the soft medium when heated and compressed. Therefore, the compression/heating process of the gas could be either constant temperature (isothermal), constant pressure (isobaric) or constant volume (isochoric). Though the compression/heating process of solids can be constant temperature (isothermal), and constant pressure (isobaric), it can not be a constant volume (isochoric), At high P-T, the pressure for the ideal gas is calculated by the force divided by the area, while the pressure for the solid is calculated from bulk modulus (K, or B) and volume at room temperature, or from Eq (1) at high P-T. A pressure gauge's bulk modulus is known, and its thermal equation of state is well known. To study a solid with unknown bulk modulus, it has to be loaded with a pressure gauge, and its pressure will be determined from its pressure gauge.
The most common pressure gauges are Au, Pt, Cu, and MgO, etc. When two or more pressure gauges are loaded together at high P-T, their pressure readings should be the same. However, large discrepancies have been reported in pressure determination using different pressure gauges or different thermal equations of state for the same pressure gauge. Fig.1 is a schematic plot showing the discrepancy in paper.
Out of the total pressure in Eq.(1), the first term pressures on the right side of Ag, Cu, Mo, Pd at room temperature are consistent in a wide pressure range, according to the Mao ruby scale up to 1 Mba. In addition, the first term pressure of Ag, Cu, and MgO are consistent according to third-order Birch–Murnaghan equation of state. Therefore, the discrepancy of the total pressure, P(V, T), should be from the second term in Eq. 1, which is the thermal pressure Pth(V, T) at high P-T.
Thermal pressure
Anderson thermal pressure model
In 1968, Anderson developed for the thermal gradient, and its reciprocal correlate the thermal pressure and temperature in a constant volume heating process by . Note, thermal pressure is the pressure change in a constant volume heating process, and expressed by integration of .
Anderson thermal pressure model is the first thermal pressure model and it is the most common thermal pressure model as well.
Experimental
The thermal pressure is the pressure change in a constant volume heating. In the section above, there are large discrepancies in pressure determination using different pressure gauges or different thermal equations of state for the same pressure gauge, however, the pressure determination in the heating process need to be reliable to measure the thermal pressure in experiments. In addition, to measure the thermal pressure in experiments, the heating process has to be a volume constant (isochoric) process. According to the first section above, an heating for a solid can not be a isochoric, so the pressure change in a non-isochoric heating process is not exactly the thermal pressure.
When a solid is loaded with a pressure gauge, and heated/compressed together at high P-T, the thermal pressure of the solid does not equal that of its gauge. The pressure is a state variable, while the thermal pressure is a process variable. A solid is subject to the same pressure as its gauge, In a heating process from T1 to T2, if the solid's volume is kept constant by compression, most likely its pressure gauge's volume will not be constant in the same heating process. In paper, the authors demonstrate that, , and , so
which means the thermal pressure of a solid doesn't equal that of its gauge.
Determination from models
According to the Anderson model, thermal pressure is the integration of the product thermal expansion and bulk modulus , i.e. . In this model, both and are pressure dependent and temperature dependent, so integrating the αp and KT in an isochoric process over temperature is not straight forward. To bypass this issue, the P-T dependent and are assumed to constant and . But authors in publication demonstrated that the model predicted pressure of Au and MgO from constant and at ambient pressure deviate from its experimental values, and the higher temperature, the higher deviation. A cartoon plot for the pressures predicted from thermal pressure version equation of state in paper is shown in Fig. 2 here.
Authors in paper proposed an altenate way to make the integration of ) possible. They assumes the thermal expansion to be pressure independent, and reduce the P-T dependent and to only temperature dependent. But in a preprint paper, author proved that pressure independent thermal expansion leads to the bulk modulus to be temperature independent, which again reduce the P-T dependent and to constant and .
There are various other thermal pressure models, but accurately determined thermal pressures are required to prove these models.
Pressure-dependent thermal expansion equation of state
It was explained that the thermal pressure can not be accurately determined in experiments in section "The thermal pressure from an experiment" above, and the thermal pressure can't accurately calculated from Anderson model above.Thermal expansion equation of state has been proposed before, which consists of a thermal expansion at ambient pressure and followed by an isothermal compression at high temperature. In this model, there is no thermal pressure term, but accurate pressure determination high P-T and temperature dependent KT are of big challenge at the present. In paper, the authors proposed a different thermal expansion equation of state, which consists of isothermal compression at room temperature, following by thermal expansion at high pressure. To distinguish these two thermal expansion equations of state, the latter one is called pressure-dependent thermal expansion equation of state.
To deveop the pressure-dependent thermal expansion equation of state, in an compression process at room temperature from (V0, T0, P0) to (V1, T0,P1), a general form of volume is expressed as
.................................(1)
f in the above expression is the mathematical relation between volume and temperature, pressure. It could be expressed by various models, such as Murnaghan, modified Tait, natural strain, Vinet, Birch-Murnaghan, and others. Its inverse function of pressure can be written as
............................(2)
The thermal expansion in an isobaric heating process from (V1, T0, P) to (V, T2,P) can be expressed as
V1= V·exp(-∫T0T2αp·dx).......................................................(3)
The authors integrate the thermal expansion formula Eq. (3) into Eq. (2), and call V·exp(-∫αp·dx) as VM, and yield the general form of thermal expansion equation of state from (V0, T0, P0) to (V, T2,P)
...........................(4)
Here V is the volume after the isobaric heating. In paper, authors explained in detail how to develop Eq (4), and took the third order Birch Murnaghan as an example.
To partially prove the pressure-dependent thermal expansion equation of state, the authors collected a set of MgO x-ray diffraction data at various temperatures at ambient pressure. At ambient pressure, P=0 GPA is known, so, the volume, pressure, and temperature are all given. Then, authors predict the pressure value from the given (V, T) from pressure-dependent thermal expansion equation of state. The predicted pressures match with the known experimental value of 0 GPa, see in Figure 2. In addition of MgO, the authors demonstrate that the Au has a similar trend as well. In the future, the validation of the pressure-dependent thermal expansion equation of state at high P-T conditions is required.
The pressure dependent αp has to be determined from an isobaric heating process. It has been reported that the heating in DAC with membrane at high P-T were isobaric. Authors in the paper propose a reversible isobaric heating concept, in which the plotted heating data points and cooling data points line on the same curve. Authors consider this heating and cooling process very close to the ideal isobaric. A cartoon plot of reversible heating/cooling proposed in paper is shown as Fig. 3.
In paper, the authors demonstrated the reversible isobaric heating concept by MgO at 9.5 GPa. In a reversible heating process, no pressure determination at high P-T is required, thus, avoid the difficulty of accurately determining the pressure at high P-T.
References
Equations of state | Thermal equation of state of solids | [
"Physics"
] | 2,077 | [
"Equations of state",
"Statistical mechanics",
"Equations of physics"
] |
74,324,443 | https://en.wikipedia.org/wiki/Sanjoy%20Paul | Sanjoy Paul (born January 22, 1962) is an Indian-American computer scientist who is a fellow of Institute of Electrical and Electronics Engineers and The Institution of Engineering and Technology. He was also the recipient of the Thomas Alva Edison patent award from the Research and Development Council of New Jersey. In 1997, he received the IEEE William R. Bennett Jr. award for best original paper in IEEE/ACM Transactions on Networking.
He was one of the youngest IEEE fellows and is known for his research works in the areas of the Internet of things (IoT), Artificial intelligence/Machine learning (AI/ML), Computer network, 5G and Wireless network, Multimedia streaming, and Content distribution.
Early life and education
Paul completed his bachelor's in Electronics and Electrical Communications Engineering (ECE) from the Indian Institute of Technology Kharagpur, in 1985.
He attended the Wharton Business School, the University of Pennsylvania in 2005 for a Master of Business Administration (MBA).
Career
Paul was one of the youngest IEEE Fellows and served as an editor of IEEE/ACM Transactions on Networking, guest editor of IEEE Network Special Issue on Multicasting, steering committee member of IEEE COMSNETS (Communication Systems & Networks), general chair of International Conference on Distributed Computing and Networking (ICDCN) 2011, Internet Multimedia Services Architecture and Application (IMSAA) 2010, and COMSWARE (Conference on Communication System software and Middleware) 2007, Technical Program Chair of COMSWARE 2006, and as a Technical Program Committee Member of several IEEE and ACM International.
Selected publications
Books
1998 - Multicasting on the Internet and its Applications.
2010 - Digital Video Distribution in Broadband, Television, Mobile and Converged Networks: Trends, Challenges, and Solutions.
Articles
See also
List of fellows of IEEE Communications Society
References
Rice University staff
Fellows of the Institution of Engineering and Technology
Fellows of the IEEE
Living people
1962 births
San Jose State University faculty | Sanjoy Paul | [
"Engineering"
] | 392 | [
"Institution of Engineering and Technology",
"Fellows of the Institution of Engineering and Technology"
] |
74,324,652 | https://en.wikipedia.org/wiki/Vention | Vention is a Canadian automation company whose platform combines engineering software and plug-and-play automation components. It supplies parts, designs hardware, and provides e-commerce and 3-D computer-aided design (CAD) software. Vention is headquartered in Montreal, Canada, and has offices in Berlin, Germany, and Boston, Massachusetts.
Clients
Vention's customers include engineers at more than 3,000 factories owned by companies such as Toyota, General Electric, Tesla, Siemens, and Airbus, as well as Google, Amazon, Boeing and Lockheed. Customers create, design and order custom equipment on Vention's online platform to be used in their production lines, including test benches, robot work stations and assembly lines. The company launched code-free robot programming tools to let users program their robot in the cloud, order the entire robot cell, and deploy it on their manufacturing floor.
History
In 2016, Vention was founded in Montreal, Canada by Etienne Lacroix, a former General Electric Co. product manager and McKinsey consultant, and Max Windisch.
In 2017, Vention raised $3.5M USD with support from White Star Capital, Bolt, and Real Ventures. In the same year, Vention announced the beta launch of its 3D CAD software - MachineBuilder.
Vention launched its MachineMotion controller and MachineApps to create a plug-and-play approach when programming equipment motions in 2018. The following year, Vention raised $13M USD in Series A funding, led by Bain Capital Ventures. In the same year, Vention launched MachineLogic, a code-free environment to program, simulate, and deploy industrial automation sequences.
Vention raised $30M USD in Series B funding in 2020, led by Georgian Partners, Bain Capital Ventures, and White Star Capital. Vention opened an EMEA office in Berlin, Germany in 2021 to provide assistance to manufacturers on both sides of the Atlantic. In the same year, Vention announced alliances with FANUC, OnRobot, and Universal Robots.
In 2022, Vention raised over $95M USD in Series C financing, led by Georgian and Fidelity, and opened a new office in Boston, Massachusetts. In the same year, Vention launched MachineCloud, software for assisted industrial automation deployment.
Vention opened a new distribution center in Montreal, Canada in 2023 with over 70,000 sq feet to assemble, test, package, and ship all North American orders. In the same year, Vention opened its Vention Experience Center, a training and development center in its Montreal headquarters, to train automation practitioners.
References
Automation organizations
Manufacturing companies of Canada
Bain Capital companies | Vention | [
"Engineering"
] | 541 | [
"Automation organizations",
"Automation"
] |
74,325,364 | https://en.wikipedia.org/wiki/Kato%27s%20inequality | In functional analysis, a subfield of mathematics, Kato's inequality is a distributional inequality for the Laplace operator or certain elliptic operators. It was proven in 1972 by the Japanese mathematician Tosio Kato.
The original inequality is for some degenerate elliptic operators. This article treats the special (but important) case for the Laplace operator.
Inequality for the Laplace operator
Let be a bounded and open set, and such that . Then the following holds
in ,
where
is the space of locally integrable functions – i.e., functions that are integrable on every compact subset of their domains of definition.
Remarks
Sometimes the inequality is stated in the form
in
where and is the indicator function.
If is continuous in then
in .
Literature
References
Functional analysis
Inequalities
Differential operators | Kato's inequality | [
"Mathematics"
] | 162 | [
"Mathematical analysis",
"Functions and mappings",
"Functional analysis",
"Mathematical theorems",
"Mathematical objects",
"Binary relations",
"Mathematical relations",
"Inequalities (mathematics)",
"Mathematical problems",
"Differential operators"
] |
74,326,228 | https://en.wikipedia.org/wiki/Lunar%20Surface%20Magnetometer | The Lunar Surface Magnetometer (LSM) was a lunar science experiment with the aim of providing insights into the interior of the Moon and how its latent magnetic field interacts with the solar wind. It was deployed on the Moon as part of Apollo 12, Apollo 14 and Apollo 16 missions.
Background
Two lunar orbital satellites, Luna 10 and Explorer 35, laid much of the groundwork for a working understanding of the Moon's magnetic field. They established that the Moon has at best little more than a remnant field, and at worst no intrinsic magnetic field at all. Those spacecraft's instruments were not sensitive enough, and too far from the Moon's surface to distinguish between these two possibilities. In addition to these two missions, analysis had been conducted on regolith samples brought back from the Moon by Apollo 11. This analysis established some of the surface materials' magnetic properties.
Instrument
A lunar magnetometer experiment had a number of requirements that shaped its capabilities. The instrument needed to be able to operate during the lunar night since it was believed the collection of data from a full lunar rotation would be required. The instrument also needed to be able to perform its own self-calibrations on a regular cadence to account for wide temperature ranges experienced over a long period of time.
The instrument's main magnetic measurements were calculated from three Ames fluxgate magnetometer sensor heads, located at the end of three booms, positioned perpendicular to each other. Each sensor consists of a flattened toroidal core made of permalloy tape placed inside a wound sensing element. The sensors could be gimballed by motors, controlled either from commands sent from Earth or from commands generated by the Apollo Lunar Surface Experiments Package (ALSEP). These sensors were thermally controlled by thermistors driving the operation of resistance heaters. Alignment and positional measurement of the instrument were provided by two features: the onboard gravimeters that measured the tilt-angle of the magnetometer, and a sundial or "shadowgraph" that enabled astronauts to take an azimuthal reading. The sensor booms were folded to facilitate easier stowage and reduced strain during transportation during flight. When deployed, the three sensors were situated above the ground at a 35-degree angle from the surface.
To be able to measure the magnetic properties of the Moon as a whole, instrument placement would need to avoid any localised nickel-iron/stoney-iron material. If this material was magnetized or capable of producing localised induction fields, this would result in incorrect readings of the Moon-wide magnetic field.
The magnetometer received its power from a 70 watt radioisotope thermoelectric generator that provided power to a number of ALSEP instruments which enabled the LSM to operate both day and night. The instrument would on average use 3 watts of power. Power and a connection to the ALSEP radio transmitter were made available via a ribbon cable.
Deployment and missions
Apollo 12
The first LSM was fully deployed and activated on the Moon at 14:40 UTC November 19, 1969, by astronauts Charles Conrad and Alan Bean, within the Oceanus Procellarum. In the selenographic coordinate system, the instrument was located at 23.35W and 2.97S. The instrument returned the first measurements of a magnetic field intrinsic to the Moon, rather than induced by the solar wind. The instruments detected a field strength of 32-36 nanotesla that was likely produced mainly by a nearby localised magnetised body, between and from the magnetometer. This was due to constraints on the lunar magnetic dipole strength due to measurements made simultaneously by Explorer 35, and the ruling out of other artificial sources due to their size. The instrument likely detected a field effect caused by the hydromagnetic flow of the solar wind as it passed the Moon.
Apollo 16
While the instrument carried on Apollo 16 was similar to that on Apollo 12, its sensors were upgraded with high stability cores developed by the Naval Ordnance Laboratory.
References
Apollo program hardware
Magnetism in astronomy
Magnetometers | Lunar Surface Magnetometer | [
"Astronomy",
"Technology",
"Engineering"
] | 820 | [
"Magnetism in astronomy",
"Magnetometers",
"Measuring instruments"
] |
74,326,302 | https://en.wikipedia.org/wiki/Solar%20Wind%20Spectrometer | The Solar Wind Spectrometer was a scientific package that flew on the Apollo 12 and Apollo 15 missions to the surface of the Moon. The goal was to characterise the solar wind near the Moon's surface and to explore its interactions with the lunar environment. The experiments' principal investigator was Dr Conway W. Snyder of the Jet Propulsion Laboratory.
Instrument
The Solar Wind Spectrometer (SWS) experiment aimed to provide the ability "to measure energies, densities, incidence angles and temporal variations of the solar wind plasma that strikes the surface of the moon". The experiment instrument consist of seven Faraday cups, that measure the amount of charged particles. One central cup points perpendicularly to the surface. The other six cups are angled at 30 degrees from the surface, located around the central cup in 60-degree intervals. Each cup can measure incoming negatively charged electron flow and positively charged proton-alpha particle flow. The angle of the incoming particle was measured by using readings from all Faraday cups.
Below the instrument was an electronics package located in a container with active thermal control. The electronics packages consists of power control circuits, sensor voltage control, ammeter circuits, and finally signal/data conditioning circuits. Thermal control was provided by three radiators, a sunshield and insulation.
Missions
Apollo 12
The Apollo 12 Solar Wind Spectrometer was deployed by astronaut Pete Conrad on the surface of the Moon on November 19, 1969. It was located at 3S, 23W. The instrument's initial state had dust covers over the Faraday cup entrances. During the early phase of the experiment's activation with the dust covers in place, background baseline data was collected. One hour after the departure of the Apollo 12 Lunar Module ascent stage at 15:25 on November 20, 1969, the dust covers were removed and the sensors exposed directly to the lunar environment.
Apollo 15
The Apollo 15 Solar Wind Spectrometer was deployed on the surface of the Moon on July 31, 1971, and was powered on at 19:37 UTC. It was located at 26N, 4E. The instrument's initial state had dust covers over the Faraday cup entrances. During the early phase of the experiment's activation with the dust covers in place, background baseline data was collected. One hour after the departure of the Apollo 15 Lunar Module ascent stage on August 2, 1971, the dust covers were removed and the sensors exposed directly to the lunar environment.
Science
Analysis of the two instruments' data found that the solar plasma found near to the lunar regolith surface was broadly similar to the solar plasma measured by probes some distance from the Moon. It also found that no plasma is detectable in the shadow of the Moon during the lunar night. The instrument was also able to distinguish plasma within interplanetary space and that found in the Earth's magnetosheath. Magnetosheath plasma would exhibit large and frequent changes in plasma velocity, density and speed. Highly variable spectra were observed at lunar sunrise, potentially due to interactions with the lunar surface.
Solar Wind Spectrometer data that was analysed after the landing of Apollo 14, confirmed the presence of a photoelectric layer and similar in nature to that found by the Charged Particle Lunar Environment Experiment.
The instrument detected a neutral gas-ion shockwave produced by the impact of the Apollo 13 S-IVB stage on the lunar surface. It was suggested that the source of this gas shockwave may be a result of the vaporisation of 1100 kg of plastic materials contained with the rocket stage. The shockwave was estimated to have travelled 140 km at a speed of 2 km/s.
References
Jet Propulsion Laboratory
Apollo 12
Apollo 15
Spectrometers
Lunar science
Apollo program hardware | Solar Wind Spectrometer | [
"Physics",
"Chemistry"
] | 752 | [
"Spectrometers",
"Spectroscopy",
"Spectrum (physical sciences)"
] |
74,326,685 | https://en.wikipedia.org/wiki/Bear%20%28app%29 | Bear is a note-taking application by Shiny Frog. Bear 2 launched for macOS, iOS and iPadOS in July 2023.
History
After 3 years of development, the initial version of Bear was released in October 2016 for macOS, iOS and iPadOS. It was released as free application, with an optional paid subscription, that unlocks more advanced features, e.g. note syncing and app themes. In the same year, the application received Apple's Mac App of the Year Award.
In 2017, support for the Apple Watch was added and Shiny Frog received an Apple Design Award for their work on Bear.
Within one year of the initial release, the team started to work on version 2, while still releasing continuous updates for Bear 1. To implement all the features planned for Bear 2, the development team had to build a new text-editing system, code-named Panda. This new system is also needed for a future Bear web application. Version 2 was eventually released in July 2023 for macOS, iOS and iPadOS.
Features
notes are written in Markdown
(nested) tags are used to organize the notes
export to plain text, Markdown, TextBundle and RTF
export to PDF, JPG, HTML, DOCX and ePub *
search inside PDFs and images *
synchronization with iCloud *
GIF support
support for sketches
web clippers for Safari, Google Chrome and Firefox
note encryption *
* marks features that are only available to paying users
See also
Comparison of note-taking software
References
Further reading
MacOS software
IOS software
Note-taking software
2016 software | Bear (app) | [
"Technology"
] | 329 | [
"Mobile software stubs",
"Mobile technology stubs"
] |
74,327,345 | https://en.wikipedia.org/wiki/Anatoly%20Radyushkin | Anatoly V. Radyushkin is a physicist.
Radyushkin completed his master's degree and PhD in physics at the Moscow State University in 1975 and 1978, respectively. He then earned a Doctor of Science degree at the Joint Institute for Nuclear Research in 1987. Radyushkin joined the Old Dominion University faculty in 1992, and also worked for the Thomas Jefferson National Accelerator Facility.
Radyushkin was elected a fellow of the American Physical Society in 1996, "[f]or pioneering studies of exclusive processes in quantum chromodynamics and applications of QCD sum rules to hadronic form factors." In 1998, he was one of three faculty members at Old Dominion to receive the university's Eminent Scholar Award. In 2015, the Southeastern Section of the APS named Radyushkin the recipient of the 2015 .
References
Theoretical physicists
Fellows of the American Physical Society
Old Dominion University faculty
Moscow State University alumni
Year of birth missing (living people)
Living people
20th-century physicists
21st-century physicists | Anatoly Radyushkin | [
"Physics"
] | 213 | [
"Theoretical physics",
"Theoretical physicists"
] |
74,327,465 | https://en.wikipedia.org/wiki/Time-traveler%20UFO%20hypothesis | The time-traveler hypothesis, also known as chrononaut UFO, future humans, extratempestrial model and Terminator theory is the proposal that unidentified flying objects are humans traveling from the future using advanced technology. Some notable people have given recent public exposure to the hypothesis, such as retired NASA aerospace engineer Larry Lemke, Wisconsin congressman Mike Gallagher, and American filmmaker Steven Spielberg.
The time-traveler hypothesis is considered extremely implausible by mainstream scholars and is generally regarded as unorthodox even among fringe conspiracy theorists who argue that UFOs are extraterrestrial spacecraft or interdimensional phenomena.
Antecedents
Origins of time travel speculation
The notion of time travel from the future to the past is thought to have been introduced for the first time in literature by French botanist and geologist Pierre Boitard in his popular 1861 book Paris avant les hommes (Paris before Men), featuring a man sent back to prehistoric Earth where he interacts with an ape-like ancestor, A few years later, in 1887, Camille Flammarion published Lumen, a novel featuring an alien soul traveling through different worlds and historical periods.
Although traveling back in time is almost-universally considered physically impossible, theoretical research has explored whether it might be possible. It has also been speculated by scientists such as J. Richard Gott, Ronald Mallet and others that humans may someday be able to time travel to the past.
Speculation of future human evolution
Many authors and researchers have speculated about the future evolution of mankind. In 1888 English author H. G. Wells published his famous science-fiction novella The Time Machine featuring a future evolution of humans and is generally regarded as one of the first modern instances of both time travel and speculative evolution. Other writers on speculative evolution include Edgar Rice Burroughs, British philosopher and science fiction writer Olaf Stapledon with his 1930 "future history" novel Last and First Men, American author Kurt Vonnegut in Galápagos, British writer Stephen Baxter in Evolution, Turkish artist and author Cevdet Mehmet Kösemen in All Tomorrows and others. Climate change, the technological singularity, space travel and genetic enhancement have also been identified as potential factors capable of altering the evolution of humans in the future, leading to different transhuman and posthuman scenarios.
UFOs and initial explanations
Human beings have reported unknown objects in the skies since antiquity. In the 1890s, a wave of mystery airships sightings was reported throughout the US, followed by Foo fighters and ghost rockets during World War II.
The modern UFO era began in the Summer of 1947, days after the United States announced plans to re-industrialize Germany over strenuous Soviet objection, sparking the Cold War. Amid fears of a Soviet response, civilian pilot Kenneth Arnold reported witnessing a formation of supersonic aircraft. Wartime prohibition of live "man on the street" broadcasts having ended, Arnold's sighting was covered nationwide on radio and print media. In the days and weeks following the Arnold sighting, a nationwide craze swept the nation as over 800 copycat sightings were published in the English-speaking press. 1947 sources speculated that the sightings resulted from novel US or Soviet technology, misidentification of mundane objects, or behavioral effects like mass hysteria; Fringe sources suggested that the sightings were a sign of the end of the world, were angelic or demonic, or were vehicles carrying people from other planets or other "dimensions".
Formation and spread
Implausibility of humanoid aliens
Contactee and Alien Abduction folklore often describe encounters with human or humanoid figures and abductors. In his 1964 article The Nonprevalence of Humanoids George Gaylord Simpson claimed that it is extremely unlikely that there exists any form of extraterrestrial intelligence in the Solar System or elsewhere and that, even if they did exist, it was even more unlikely that they would be humanoids. His article was cited and analysed, alongside evolutionary biologist Theodosius Dobzhansky’s similar view on the implausibility of the evolution of humanoid extraterrestrial life forms, in the famous 2014 collection of essays Archaeology, Anthropology and Interstellar Communication edited by astrobiologist Douglas Vakoch and published by NASA in 2014. In the late 1980s, evolutionary biologist and historian of science Stephen Jay Gould put forth his famous thought experiment that if evolution was rewound and played back again it would likely take a very different course and humans would never evolve, which in addition to his declared view against human-oriented evolutionary teleonomy, helped shaped the established view that if intelligent extraterrestrials did exist, they would likely not resemble humans. Biologist Jack Cohen has assumed a similar position about the iconic representation of the Grey alien from reports of UFO abduction and close encounters, stating that extraterrestrials from an alien world could not have evolved a physiology so similar to humans'.
Modern popularization
It is unclear exactly when the hypothesis in its complete form was first proposed. Early versions surfaced between the 1970s' pseudoscientific literature and 1990s internet culture, at times associated with the idioms "chrononaut UFOs", "time traveling humans" or simply "future humans". Examples include contributions by Jacques Vallée in his book The Invisible College, Radford University anthropology professor and former Forbes contributor David S. Anderson, Jenny Randles' 2001 book Time Storms, James Herbert Brennan's 1997 book Time-travel: a new perspective, which also draws parallels between the time travelers and elements of the pseudoarchaeological notion of ancient astronauts and Ooparts, and many others. In their 1998 book The Day After Roswell, US Army officer Philip J. Corso and American novelist William J. Birnes reported that German physicist and engineer Dr Hermann Oberth believed the craft recovered at Roswell could have been a time machine.
On April 27, 2012 History aired the "Time Travelers" episode from season 4 of the series Ancient Aliens produced by Prometheus Entertainment, available on Netflix since 2022. In the same year, the "Time Benders" episode from season 18 of the same series aired on History, exploring other aspects of the concept and featuring more speakers, including American professor of biological anthropology Michael P. Masters from the Montana Technological University in Butte, Montana and British journalist and Ministry of Defence civil servant Nick Pope. Pope linked the Rendlesham Forest incident in the UK and the Cabo Valdés Case in Chile with the time-traveler hypothesis, a connection he also explored in his 2014 book (written with John Burroughs, USAF, Ret., and Jim Penniston, USAF, Ret.) Encounter in Rendlesham Forest: The Inside Story of the World's Best-Documented UFO Incident, published by St. Martin's Press. The two episodes feature, among others, ufologists Giorgio A. Tsoukalos, Sean David Morton, authors Erich von Däniken, David Hatcher Childress, Philip Coppens, and theoretical physicist Ronald L. Mallett, discussing the time-traveler hypothesis in the contexts of pseudoarchaeology and pseudohistory.
In 2013, the Huffington Post published an article describing the time-traveler hypothesis and often referencing the Ancient Aliens episode. In the article, the author also reports an online conspiracy theory about how U.S. Navy Commander George W. Hoover allegedly revealed to his son, George Hoover Jr. and later to ufologist William J. Birnes, that the Roswell incident may have involved human beings from the future rather than aliens and that he believed those "beings" were not extraterrestrial, but rather "extratemporal" in nature. The article goes on linking Hoover's story to other alleged UFO sightings and UFO abduction accounts with similar statements and reports about aliens actually being "humans of the future who have found the technology to overcome the limitations of light speed and time travel paradoxes that keep present day humans from breaching the boundaries of time" and that their "often-humanoid appearance may suggest a link between the way we look today, and what we might look like thousands of years from now."
In his 2019 book Identified Flying Objects and subsequent 2022 volume The Extratempestrial Model, Dr Masters explored more in depth various aspects of the time-traveler hypothesis, including fringe ancient astronauts theories and possible future development scenarios of human anatomy such as brain growth, craniofacial evolution, bipedalism, paedomorphism and more. Masters and his theory were featured on various podcasts, such as Sean Patrick Hazlett's Through the Glass Darkly, and The Cryptid Factor co-hosted by New Zealand journalist David Farrier, comedian Rhys Darby, producers Dan Schreiber and Leon Kirkbeck.
In 2020 WatchMojo published a video on the topic. In the same year, TNW also published an article about Masters' extratempestrial model. In June 2022, British ESA astronaut Tim Peake mentioned the time-traveler hypothesis in an interview on Good Morning Britain. In a 2023 interview with Stephen Colbert from The Late Show, American filmmaker Steven Spielberg also mentions the theory.
A number of motives for the time-travelers are put forth in the different media where the hypothesis is discussed, such as historical or paleoanthropological interest to study our own past, as well as tourism.
In popular culture
The 1966 Sherwood Schwartz TV series It's About Time portrays 20th-century astronauts being sent back to the stone age after traveling around the earth faster than the speed of light. The astronauts have to contend with the suspicions and superstitions of local cave-dwellers, who regard their advanced technology as sorcery. The astronauts eventually repair their space capsule and return to 1967 with the prehistoric family they befriended.
In Gregory Benford’s 1980 novel Timescape, scientist Saul Shriffer, a colleague of Frank Drake at the SETI Project Ozma, believes that a cryptic signal is of extraterrestrial origin, when it fact it had been sent thirty-four years into the past by humans in the future.
In his 1984 science fiction/fantasy novel Birds of Prey, American author David Drake describes six sterile and mutually telepathic sisters who time travel back in time to save humanity from an intelligent but monstrous alien species similar to social insects. The plot suggests that in the future humanity evolves to be quite different from its present form and that the six sisters, along with many other future humans, had become more similar to the insectoid aliens, somewhat of a hybrid between hominids and worker ants or bees, in their attempt to fight them for survival.
In Michael Crichton's 1987 novel Sphere (and subsequent film adaptation of the same name), what was thought to be an alien craft at the bottom of the Pacific Ocean turns out to be a ship built by humans from the future.
In 1993, Syfy (at the time "Sci-Fi Channel") produced their first original TV film, Official Denial, directed by Brian Trenchard-Smith and written by Bryce Zabel, in which a man named Paul Corliss, played by Parker Stevenson, is abducted by aliens who at the end of the movie are revealed to be humans from the future.
In the fifteenth comic book of the Belgian series Blake and Mortimer, The Strange Encounter (2001), British physicist Philip Mortimer and Dr. Walt Kaufman from SUFOS (section of UFO Studies) investigate the corpse Major Lachlan Macquarrie disappeared in the Battle of Saratoga in 1777 after the appearance of three mysterious lights and reappeared in the present under the same circumstances, wearing a baldric inscribed with the words "Yellow King, 8061, Danger, Light, Plutonian, H, Poplar trees, Temple 1954". The same night of the autopsy, Mortimer fights an intruder wearing identical 18th century clothes and anachronistic items to Macquarrie. In the clash, the intruder falls and dies, revealing alien-like features under a human-suit. Based on the mysterious clue found on Major Macquarrie, they hypothesize that the alien could be from Pluto only to instantly realize that his physiology is unsuitable to survive the planet's harsh environment. Later, the dwarf-like alien scientist Dr. Z'ong reveals to Mortimer that commander Basam Damdu, absolute dictator of the Yellow Empire from The Secret of the Swordfish, along with his army, including Zong himself, are humans from 8061, a time when the earth is deserted due to a long nuclear war in the 21st century and humans are an endangered species with alien-like deformities. Some of these plot elements are similar to another earlier episode The Time Trap, where similar events such a post-nuclear dystopian Earth and a rising world order led by a tyrant take place in the 51st century, year 5060.
The English progressive rock band Yes wrote a song titled Aliens (Are Only Us from the Future) entirely dedicated to the subject. The track had been performed during Yes's In the Present world tour, but was never released, until the band's bassist Chris Squire decided to finally published it in 2012 together with English rock band Genesis’s guitarist Steve Hackett and Travis singer Fran Healy as co-writer, calling it simply "Aliens", on their only studio album, A Life Within a Day.
Jordan Peele's 2022 horror movie Nope references "futuristic humans coming back in time to stop us from destroying the planet."
The 2014 movie Interstellar contains deus ex machina beings who built the tesseract environment inside the supermassive black hole Gargantua and possibly placed the wormhole near Saturn that will lead the crew of the Endurance to three potentially habitable exoplanets. These "superior" entities – called bulk-beings by American physicist Kip Thorne in The Science of Interstellar, and referred to by the characters of the movie as "they" – are later revealed by the protagonist Cooper to be humans from the future who evolved to exist in five dimensions, guiding him and his daughter Murph through the necessary steps to crack the equation of quantum gravity and save humanity.
Terminology and connection to other theories
Although in his books and publications Dr Masters uses the neologism "extratempestrial" to describe his model and the alleged beings piloting the UFOs, the overall idea has been dubbed "the time-traveler hypothesis" by executive director of nonprofit Mutual UFO Network (MUFON), Jan Harzan.
The time-traveler hypothesis and the interdimensional hypothesis overlap by a certain degree. People in the ufology community, such as former MUFON director for the state of Pennsylvania John Ventre in an interview with KDKA News Radio, as well as American parapsychologist and engineer Harold E. Puthoff, refer to the two interchangeably. Dr Masters has stated that he considers his extratempestrial model a subcategory of the interdimensional hypothesis. Indeed, from a more scientific standpoint – albeit controversially – within the framework of the many-worlds interpretation of quantum mechanics, temporal paradoxes could be avoided if the time traveler would move from one dimension, or parallel universe, or timeline, to another.
Similarly to how the extraterrestrial hypothesis represents a potential solution to Fermi's paradox, the time-traveler hypothesis provides an alternative explanation for the absence of future time travelers. In an interview with Nova on PBS, astrophysicist and skeptic Carl Sagan stated that there's a possibility that time travelers from the future are already here and we simply don't have the means or the knowledge to recognize them as such, or have other names for them, such as "UFOs or ghosts or hobgoblins or fairies" and that he doesn't think "that the fact that we're not obviously being visited by time travelers shows that time travel is impossible."
Criticism
The time-traveler hypothesis is considered pseudoscientific. American astrophysicist Neil deGrasse Tyson has referred to the hypothesis as illogic. UFO skeptic Robert Sheaffer criticized Masters' work because it relies on "the belief that time travel is not only possible, but real."
British astronomer and science writer David J. Darling has stated that the extraterrestrial hypothesis and the time-travel hypothesis are equally reasonable yet highly unlikely and unnecessary and that, although certain aerial phenomena have indeed eluded identification, there is no apparent reason to justify the claim that they're artificial and/or not of this world. Furthermore, he added that "if some UFOs are 'alien' craft, it's just as reasonable to suppose that they might be time machines from our own future than that they're spacecraft from other stars. The problem is the 'if.' (...) Outside of the popular mythos of flying saucers and archetypal, big-brained aliens, there's precious little credible evidence that they exist. So, my issue with the (Masters') book is not the ingenuity of its thesis, but the fact that there's really no need for such a thesis in the first place."
Referring to the Rendlesham incident, science writer and UFO skeptic Ian Ridpath wrote that time-traveling UFO allegations from retired sergeant Jim Penniston's hypnosis session may have been influenced by him watching the sci-fi film Official Denial (which aired in 1993 and released on video in May 1994, a few months before Penniston's claim surfaced in September of the same year), suggesting a Life imitates art situation, with the film causing Penniston's false memory.
In February 2022, American futurist and science communicator Isaac Arthur discussed the odds against the time-traveler hypothesis on episode 23 Are Aliens Just Time Traveling Humans of the podcast It's Probably (not) Aliens, specifically debunking the concept as it was exposed on the ‘Time Travel’ episode of the Ancient Aliens series.
When asked about the plausibility of UFOs being future humans, Queensland University quantum physicist Fabio Costa told Popular Mechanics: "In a sense, traveling back in time requires two doors, one in the future and one in the past. You can only travel back if someone has opened the door to the past. So, people from the future cannot visit us... unless someone has already invented a time machine and nobody knows! (...) That leaves open the question: where is the time machine?"
See also
Time travel
Posthumanism
Transhumanism
Timeline of the far future
Longtermism
Speculative Evolution
Cryptoterrestrial hypothesis
Psychosocial hypothesis
Interdimensional hypothesis
Space animal hypothesis
References
Pseudoscience
Time travel
UFO conspiracy theories
Ufology | Time-traveler UFO hypothesis | [
"Physics",
"Technology"
] | 3,833 | [
"Physical quantities",
"Time",
"Science and technology-related conspiracy theories",
"Time travel",
"UFO conspiracy theories",
"Spacetime"
] |
74,327,726 | https://en.wikipedia.org/wiki/NGC%205532 | NGC 5532 is an elliptical galaxy located in the constellation Boötes. It is located at a distance of about 250 million light years from Earth, which, given its apparent dimensions, means that NGC 5532 is about 110,000 light years across. It was discovered by William Herschel on March 15, 1784. It is a Fanaroff–Riley type 1 (FR1) radio galaxy.
NGC 5532 is an elliptical galaxy located in a galaxy group. In the centre of the galaxy lies a warped disk, while the isophotes display boxiness and the centre of the galaxy doesn't coincide with the isophotal centre. The core appears obstructed in X-rays, with a column density of cm−2, which is considered high for a FR1 galaxy. In the centre of the galaxy lies a supermassive black hole whose mass is estimated to be (630 millions) based on the M–sigma relation.
Two straight radio jets emerge from the galaxy core and form sharp edged lobes that appear to engulf the jets, although this could be a projection effect. The jets are typical of a Fanaroff–Riley type 1 radio galaxy, with faint bases that brighten abruptly 2.7 arcseconds from the nucleus and then the brightness gets lower at the distance from the core increases. The jet appears moving with relativistic speeds, 0.8 times the speed of light at the start of the jet. The northern jet has been observed in X-rays by the Chandra X-ray Observatory, with emission detected at distances between 2 and 10 arcseconds from the core.
NGC 5532 is located in a galaxy group that also includes the galaxy NGC 5531. NGC 5532 forms a pair with lenticular galaxy NGC 5532A, which lies at a distance of about 16 kpc. 21 galaxies have been as members of the group, lying within one megaparsec from NGC 5532.
Two supernovae have been observed in NGC 5532: SN 2007ao (type Ia-p mag. 17.7), and SN 2023omo (type Ia-91bg-like, mag. 18.3).
Gallery
See also
NGC 4261 - a similar radio galaxy
References
External links
NGC 5532 on SIMBAD
Elliptical galaxies
Radio galaxies
Boötes
5532
09137
296
51006
Discoveries by William Herschel
Astronomical objects discovered in 1784 | NGC 5532 | [
"Astronomy"
] | 496 | [
"Boötes",
"Constellations"
] |
74,329,325 | https://en.wikipedia.org/wiki/Cyber%20Assessment%20Framework | The Cyber Assessment Framework is a mechanism designed by NCSC for assuring the security of organisations. The CAF is tailored towards the needs of Critical National Infrastructure, to meet the NIS regulations, but the objectives can be used by other organisations.
In addition to national public-sector and infrastructure bodies, the CAF is also being used by local government.
Principles
The CAF has fourteen objectives, grouped into four categories: These set high-level objectives which fit the needs of organisations handling high-impact data or performing essential functions. These have some similarities, but are not identical, to the categories of controls used by ISO 27001:2013.
Objective A: Managing security risk
A.1 Governance
A.2 Risk management
A.3 Asset management
A.4 Supply chain
Objective B: Protecting against cyber attack
B.1 Service protection policies and procedures
B.2 Identity and access control
B.3 Data security
B.4 System security
B.5 Resilient networks and systems
B.6 Staff awareness and training
Objective C: Detecting cyber security events
C.1 Security monitoring
C.2 Anomaly detection
Objective D: Minimising the impact of cyber security incidents
D.1 Response and recovery planning
D.2 Improvements
Each of these are linked to "outcomes" and "contributing outcomes". There are a total of 14 outcomes and 39 contributing outcomes. NCSC has published Indicators of Good Practice; IGP tables can be used to assess whether each objective has been "Achieved", "Not achieved", or "Partially achieved". Organisations are expected to self-assess, and to draw up an improvement roadmap. Competent Authorities review the assessment and the roadmap.
Further reading
Introduction to the Cyber Assessment Framework
See also
ISO 27001
GovAssure
Cyber Essentials
Security Policy Framework
References
Cybercrime in the United Kingdom
Government of the United Kingdom
Information technology organisations based in the United Kingdom
National security of the United Kingdom
Information assurance standards
Information governance | Cyber Assessment Framework | [
"Technology"
] | 388 | [
"Computer standards",
"Information assurance standards"
] |
74,329,409 | https://en.wikipedia.org/wiki/Smart%20data%20capture | Smart data capture (SDC), also known as 'intelligent data capture' or 'automated data capture', describes the branch of technology concerned with using computer vision techniques like optical character recognition (OCR), barcode scanning, object recognition and other similar technologies to extract and process information from semi-structured and unstructured data sources. IDC characterize smart data capture as an integrated hardware, software, and connectivity strategy to help organizations enable the capture of data in an efficient, repeatable, scalable, and future-proof way. Data is captured visually from barcodes, text, IDs and other objects - often from many sources simultaneously - before being converted and prepared for digital use, typically by artificial intelligence-powered software. An important feature of SDC is that it focuses not just on capturing data more efficiently but serving up easy-to-access, actionable insights at the instant of data collection to both frontline and desk-based workers, aiding decision-making and making it a two-way process.
Smart data capture automates and accelerates capture, applying insights in real time and automating processes based on extracted input. Smart data capture is designed to be repeatable and scalable to reduce low-level manual tasks and eliminate human error. To achieve this goal, smart data capture solutions are often made available using specialist software installed on commodity hardware such as smartphones. However, some solutions may rely on specialized hardware such as dedicated scanning devices, wearables or shop floor robots.
Differences from OCR
Optical character recognition applications are typically concerned with the actual data capture process; they are intended to faithfully reproduce text, words, letters and symbols from a printed document. Smart data capture is multimodal, capable of extracting data from a wider range of semi-structured and unstructured sources, going beyond basic text recognition to offer a wider scope of applications. By extending functionality to provide actionable insights at the point of capture, SDC is also a two-way process (capture-display), while OCR is more commonly one-way (capture only), primarily used for data input.
Smart data capture solutions typically have two parts:
Data capture (which includes OCR, barcode scanning, object recognition)
Functionality that then uses this data to provide actionable insights at the point of capture.
Applications
Smart data capture can be applied to almost any industry and application that requires visual information capture and interpretation. This may include:
Retail
Warehouse inventory control
Logistics, handling and shipping
Manufacturing
Field service
Healthcare
Transport and travel
Fraud detection
Immersive, augmented reality-driven experiences
Notes
Historically, PriceWaterhouseCoopers described smart data capture as a combination of robotic process automation and intelligent character recognition. This description is no longer sufficient because it is focused purely on text-based capture systems (automated OCR).
See also
Automatic identification and data capture
References
Automatic identification and data capture
Computer vision
Image processing | Smart data capture | [
"Technology",
"Engineering"
] | 589 | [
"Packaging machinery",
"Data",
"Automatic identification and data capture",
"Artificial intelligence engineering",
"Computer vision"
] |
72,832,029 | https://en.wikipedia.org/wiki/Sor%20%28geomorphology%29 | A sor (; ) is a closed drainless depression characteristic of the Central Asian deserts, found especially in Kazakhstan. The sor area is seasonally flooded, forming a lake, which becomes an inland salt marsh and then a salt flat as it dries.
The term forms part of some toponyms of Kazakhstan, such as Altybaysor, Aralsor, Atansor, Azhibeksor, Bauzhansor, Karasor, Koksengirsor, Mangisor, Maysor, Meshkeysor, Shandaksor, Sholaksor, Shureksor, Sorasha, Sorkol, Sormoildy, Tuzdysor, Zhaltyrsor, Zhyngyldysor and Sor Tuzbair.
Description
A sor forms in the flatland of arid areas or deserts. Heavy seasonal rains taking place usually in the spring bring the water to accumulate at the bottom of the depression. The intermittent lake is characterized by a clear-cut coastline. As the summer approaches the lake dries quickly owing to hot temperatures, forming a salt pan with a layer of salt of varying thickness. In the dry flat expanse the groundwater is located close to the surface.
Although usually a sor is located away from the seashore, an inlet in the southern coast of the Dead Kultuk had the characteristics of a sor and was known as "Sor Kaydak". However, in recent decades it lost its distinct shoreline owing to the rise of the level of the Caspian Sea and has become a salt marsh.
Flora
Located in areas of sparse vegetation, the typical sor landscape is quite barren. Tough halophytes such as Halocnemum are among the only species able to grow in such an environment.
See also
Inland salt marsh
Solonchak
References
External links
Salt Lake Colors, Kazakhstan
Geomorphology
Lacustrine landforms
Depressions (geology)
Salt flats
Turkic toponyms | Sor (geomorphology) | [
"Chemistry",
"Environmental_science"
] | 399 | [
"Hydrology stubs",
"Hydrology",
"Salt flats",
"Salts"
] |
72,832,641 | https://en.wikipedia.org/wiki/Digital%20multicast%20television%20network | A digital multicast television network, also known as a diginet or multichannel, is a type of national television service designed to be broadcast terrestrially as a supplementary service to other stations on their digital subchannels. Made possible by the conversion from analog to digital television broadcasting, which left room for additional services to be broadcast from an individual transmitter, regional and national broadcasters alike have introduced such channels since the 2000s. By March 2022, 54 such services existed in the United States.
Typically run on a lesser budget, national multicast services often rely on archive and imported content and are tailored to allow advertisers to reach specific demographics. Most of their revenue is derived from national advertising.
Digital multicast services by country
Australia
The first multichannel broadcast in Australia was ABC Kids, which broadcast from 2001 to 2003; in the succeeding years, the country's commercial broadcasters also launched secondary services to compete against DVDs and online piracy. However, their ability to do so was hampered at first by a ban on adding channels, with a focus on such services as datacasting and high-definition. It was not until 2009 that commercial broadcasters were allowed to add multichannels; in that year, the three major networks all did so, bringing the number of channels they offered from three to eleven.
The original commercial multichannels were generalist in nature, which made it difficult for advertisers to target specific demographics and therefore made them less lucrative. The shift to specifically targeted services and their reliance on existing programming has allowed these channels to survive despite drawing comparatively low shares of the audience: in 2018, 7mate led the group with an audience share of 4.1 percent among metropolitan audiences. However, after the Australian Communications and Media Authority permitted the commercial broadcasters to move required children's programming and national drama commitments to their multichannels, ratings and visibility fell precipitously; by 2013, the ABC had more viewers for its children's channels than the commercial broadcasters combined. The commercial broadcasters also became more reliant on news, sport, and reality competitions on their main channels.
Each of the five major broadcasters offers its own suite of multichannels:
ABC: ABC Kids, ABC Me, ABC News, ABC TV Plus
SBS: SBS Food, SBS Viceland, SBS World Movies, SBS WorldWatch, National Indigenous Television
Seven Network: 7Two, 7mate, 7flix, 7Bravo
Nine Network: 9Go!, 9Gem, 9Life, 9Rush
Network 10: 10 Bold, 10 Peach, Nickelodeon
Mexico
In 2017, TV Azteca launched a+ (now A Más), initially conceived as a hybrid regional-national service to be carried on its existing Azteca 7 transmitters in most of Mexico. The new channel—as well as news channel adn40, aired on Azteca Uno transmitters, achieved sufficient national coverage to be classified a national network by the Federal Telecommunications Institute in December 2017, making it mandatory for satellite TV providers to add it to their lineups.
United States
For most of the 2000s, digital multicasting in the United States remained less used. One of the earliest successful uses of subchannels was to broadcast automated weather information. The first such subchannel was the 69 News Weather Channel, launched in February 2001 by WFMZ-TV in Allentown, Pennsylvania, with the assistance of AccuWeather. In 2004, NBC and its affiliates launched NBC Weather Plus, which was available in its peak from more than 80 stations nationally. Another early subchannel user was The Tube Music Network, which broadcast music videos from 2005 to 2007 before closing for financial reasons.
2008 was a critical year in the shift toward programmed digital multicast services. NBC Weather Plus was shut down at the end of 2008 in a decision taken by the network's affiliates. Several new channels offering classic TV programming were launching or growing at the time. These included the Retro Television Network (RTN), started in 2005 by Equity Media Holdings as the first such service, and This TV, a movie service run as a joint venture between Weigel Broadcasting and film studio MGM. Another planned subchannel of this type, the .2 Network, was announced and signed up affiliates but never launched amid the Great Recession. These subchannels offered stations the ability to expand their advertising inventory and offer lower prices on the secondary services. In addition to services signing up national affiliates, some station groups were beginning to experiment around this time. CBS explored, but never launched, a complementary secondary channel, dubbed "CBS 2". In 2007, Ion Media, which owned a network of transmitters serving most major U.S. markets, launched kids channel Qubo and health and wellness service Ion Life. Weigel launched MeTV, which had formerly only been a local service in Chicago and Milwaukee, on a national basis in December 2010; four years later, it was the most widely distributed multicast network. It remains the most-watched; in 2021, it had an average prime time audience of 752,000, nearly double the next-highest diginet and greater than cable channels such as Bravo, Lifetime, and A&E.
As digital multicast services began to proliferate and gain viewers in the 2010s, they also became more specialized in an attempt to stand out and reach potential viewers. However, those that were not owned by large station groups and thus could not count on a backbone of significant national coverage struggled to negotiate distribution, having to do so with individual stations in each of the United States's more than 200 television markets. This market favored new services launched by the station groups. The business was also maturing significantly due to the rise of cord cutting, enabling some services to make a profit off advertising. Nielsen's list of top 100 television channels in 2016 did not contain any diginets; in 2018, eight made the list. This led to increased mergers and acquisitions activity. In 2017, the E. W. Scripps Company acquired Katz Broadcasting for $302 million. The purchase was notable for adding four diginets: the women-focused Escape (now Ion Mystery), the men-targeted Grit, Bounce TV to serve the Black market, and the comedy channel Laff. Scripps saw an opportunity to reduce the proportion of advertising on these services that was direct response and toward more expensive general-market advertising. The deal was seen as a validation of the diginet business. Scripps then acquired most of the Ion Media transmitter network and affiliated with the remainder in 2021, using the transmitters to broadcast a growing array of targeted, thematic diginets. Tegna, like Scripps an owner of full-service broadcast stations, acquired the Justice Network (now True Crime Network) and Quest for $91 million in 2019.
Multicast services typically pay local stations to affiliate, with higher payments going to stations with lower major channel numbers; owning the host station, as Scripps does with the Ion transmitters, allows for the reduction of costs by eliminating such payments in some markets. In some cases, switching stations can also lead to the service gaining carriage on cable in its broadcast area. For instance, in 2022, Sinclair Broadcast Group moved Comet, one of its three diginets, from WSBK-TV to WFXT in the Boston area, which also led to cable carriage for the Comet subchannel. In the late 2010s and early 2020s, diginets such as NBC-owned Cozi TV began making national distribution deals with satellite, paid streaming, and ad-supported streaming providers that previously had not carried them, further increasing their reach. Further, the use of more efficient generations of MPEG-2 encoders by TV stations allowed for the transmission of additional subchannels from the same transmitter; a representative for Harmonic, a seller of encoders, noted that stations were seeing a return on their investment within less than a year from the additional revenue stream opened up by adding another diginet.
Public television stations in the United States were also comparatively early adopters of multicasting, and public TV content distributors joined the game in the mid-2000s, such as with the launch of Create by American Public Television in January 2006. In 2016, PBS began providing a 24-hour PBS Kids service to member stations.
References
Digital television
Television technology | Digital multicast television network | [
"Technology"
] | 1,684 | [
"Information and communications technology",
"Television technology"
] |
72,834,766 | https://en.wikipedia.org/wiki/Gaussian%20brackets | In mathematics, Gaussian brackets are a special notation invented by Carl Friedrich Gauss to represent the convergents of a simple continued fraction in the form of a simple fraction. Gauss used this notation in the context of finding solutions of the indeterminate equations of the form .
This notation should not be confused with the widely prevalent use of square brackets to denote the greatest integer function: denotes the greatest integer less than or equal to . This notation was also invented by Gauss and was used in the third proof of the quadratic reciprocity law. The notation , denoting the floor function, is now more commonly used to denote the greatest integer less than or equal to .
The notation
The Gaussian brackets notation is defined as follows:
The expanded form of the expression can be described thus: "The first term is the product of all n members; after it come all possible products of (n -2) members in which the numbers have alternately odd and even indices in ascending order, each starting with an odd index; then all possible products of (n-4) members likewise have successively higher alternating odd and even indices, each starting with an odd index; and so on. If the bracket has an odd number of members, it ends with the sum of all members of odd index; if it has an even number, it ends with unity."
With this notation, one can easily verify that
Properties
The bracket notation can also be defined by the recursion relation:
The notation is symmetric or reversible in the arguments:
The Gaussian brackets expression can be written by means of a determinant:
The notation satisfies the determinant formula (for use the convention that ):
Let the elements in the Gaussian bracket expression be alternatively 0. Then
Applications
The Gaussian brackets have been used extensively by optical designers as a time-saving device in computing the effects of changes in surface power, thickness, and separation of focal length, magnification, and object and image distances.
References
Additional reading
The following papers give additional details regarding the applications of Gaussian brackets in optics.
Carl Friedrich Gauss
Continued fractions | Gaussian brackets | [
"Mathematics"
] | 435 | [
"Continued fractions",
"Number theory"
] |
72,835,176 | https://en.wikipedia.org/wiki/Soheila%20Sokhanvari | Soheila Sokhanvari (; born 1964) is an Iranian-born British multidisciplinary visual artist. She is known for her drawings and egg-tempera paintings, often featuring her memories, or based on family photographs. Sokhanvari now lives in Cambridge, where she is an associate artist at the Wysing Arts Centre, a contemporary arts residency centre.
Biography
Soheila Sokhanvari was born in 1964 in Shiraz, Pahlavi Iran. She left Iran in 1978 at the age of 14 before the Iranian Revolution, to study in the United Kingdom. After she moved away from her family and her homeland, she found greater importance in her family photos. She is a dual national with citizenship in Iran and in the UK.
She graduated with a degree (1986) in biochemistry from University of Cambridge. Sokhanvari also has a degree (2005) in fine art and art history from Anglia Ruskin University in East Anglia, United Kingdom; a postgraduate diploma from Chelsea College of Art and Design (now Chelsea College of Arts) in London; and she has a MFA degree from Goldsmiths' College.
Sokhanvari's early work featured crude oil, and eventually expanded to sepia drawings of family and pre-Iranian Revolution. Her more recent artwork is made with brightly colored egg tempera on vellum (calf skin) and she uses a squirrel hair brush (which are reminiscent of the materials used in Persian miniatures). She uses old family photographs as subjects for her paintings, and she heavily utilizes patterns. She has also painted the feminist entertainers and icons of Iran as a subject.
Sokhanvari's solo exhibitions include "Rebel Rebel" (2022–2023) at Curve Gallery, Barbican Centre in London; and "We Could Be Heroes..." (2023–2024) at Heong Gallery in Downing College, Cambridge. Her artwork can be found in museum collections including at the Los Angeles County Museum of Art, and National Gallery of Victoria.
See also
List of Iranian women artists
References
External links
Official website
Instagram
Living people
1964 births
21st-century Iranian painters
21st-century Iranian women artists
Alumni of Anglia Ruskin University
Alumni of Goldsmiths, University of London
Alumni of Chelsea College of Arts
Alumni of the University of Cambridge
Cytogenetics
Iranian emigrants to England
Iranian women painters
Multimedia artists
People from Shiraz
Women multimedia artists
21st-century women painters | Soheila Sokhanvari | [
"Technology"
] | 497 | [
"Multimedia",
"Multimedia artists"
] |
72,835,611 | https://en.wikipedia.org/wiki/Habitable%20Worlds%20Observatory | The Habitable Worlds Observatory (HWO) is a large infrared, optical, and ultraviolet space telescope recommended by the National Academies’ Decadal Survey on Astronomy and Astrophysics 2020. It will be optimized to search for and image Earth-size habitable exoplanets in the habitable zones of their stars, where liquid water can exist, by using a coronagraph to block out the light of their stars, as well as provide broad astrophysics observations. HWO builds upon studies conducted for two earlier mission concepts called the Large Ultraviolet Optical Infrared Surveyor (LUVOIR) and Habitable Exoplanets Observatory (HabEx).
Mission goals
HWO’s main objective would be to identify and directly image at least 25 potentially habitable worlds. It would then use spectroscopy to search for chemical biosignatures in these planets’ atmospheres, including gases such as oxygen and methane, which could serve as critical evidence for life. HWO would also use its high sensitivity and resolution capabilities to trace the evolution of galaxies and other cosmic structures.
The main science themes for HWO are:
Drivers of galaxy growth
Evolution of elements over cosmic time
Solar System in its galactic context
Living worlds
Development
In 2023, the National Aeronautics and Space Administration (NASA) established a Great Observatory Maturation Program (GOMAP) to unite government, industry, and academia to develop the technologies needed for HWO. GOMAP aims to draw on lessons from previous NASA missions to streamline development of the HWO concept and decrease budget and schedule risks for the future mission.
The HWO is designed to be launched on a super heavy-lift launch vehicle such as SpaceX's Starship, Blue Origin's New Glenn or the SLS. The current concept for the HWO includes a 6–8 meter mirror, however its design should allow for a larger mirror if launch vehicle technology allows by the time of its launch in the 2040s.
References
Space telescopes
Exoplanet search projects
Proposed astrobiology space missions
Proposed NASA space probes | Habitable Worlds Observatory | [
"Astronomy"
] | 413 | [
"Astronomy projects",
"Exoplanet search projects",
"Space telescopes"
] |
72,838,516 | https://en.wikipedia.org/wiki/Early%20Start%20Denver%20Model | The Early Start Denver Model (ESDM) is a form of intervention directed at young children that display early signs of being on the autism spectrum proposed by American psychiatrists Sally J. Rogers and Geraldine Dawson. It is intended to help children improve development traits as early as possible so as to narrow or close the gaps in capabilities between the individual and their peers.
Development
The American psychiatrists Sally J. Rogers and Geraldine Dawson began developing the Early Start Denver Model during the 1980s. While working at the University of Colorado, in Denver, Rogers provided what was first called the "play school model" of intervention which was applied to children in preschool during their regular play activities. The model was founded in Piaget's theory of cognitive development and came to be described by Rogers and Dawson as the Denver Model.
In 2010, the two researchers published Early Start Denver Model for Young Children with Autism: Promoting Language, Learning, and Engagement, in which the ESDM is manualized and described in detail. It is generally cited to be directed towards children between 12 and 48 months of age, and is closely related to Applied behavior analysis, influencing and being influenced by this field of work.
Description
The ESDM is aimed at using "joint activity routines" that explore the child's natural interests to explore their learning potential, shaping everyday activities between the child and their caregivers to maximize their development potential according to the child's assessment.
Rogers and Dawson describe the core features of the ESDM as:
an interdisciplinary team that implements a developmental curriculum addressing all domains;
focus on interpersonal engagement;
development of fluent, reciprocal, and spontaneous imitation of gestures, facial movements and expressions, and object use;
emphasis on both nonverbal and verbal communication development;
focus on cognitive aspects of play carried out within dyadic play routines;
partnership with parents.
Assessment
The intervention begins with measuring the child's skill levels in language, social skills, imitation, cognition, play, and motor and self-help skills. The assessment serves as a baseline for future reassessments, which are rerun every 12 weeks, and a model of it is presented in Rogers and Dawson's 2010 book, being called the ESDM Curriculum Checklist.
Intervention plan
Results from the first assessment are used to draw an intervention plan, which describes the activities to be performed with the child by the parents and therapists. An interdisciplinary team oversees the progress and readjusts the plan with every new 12-week assessment. The parents are also trained (or "coached") and play a role in the program, taking on some of the activities in the child's intervention plan or, in some cases, conducting it all together.
Among the domains focused on by the intervention plan are of particular importance: imitation, nonverbal communication (including joint attention), verbal communication, social development (including emotion sharing), and play.
Efficacy
Several studies have been published in an effort to assess its efficacy in mitigating the developmental delays in young children diagnosed with autism. Research of this kind is inherently complex, since it involves comparing groups receiving different types of treatment and it is ethically questionable to set aside a control group that would receive no treatment; therefore it is challenging to perform the objective measurement of treatment effects.
Rogers and Dawson have performed different trials of their methods. They published, with 6 other authors, a randomized controlled trial in 2012 that younger age and longer hours of weekly intervention hours positively correlate with improvements in most variables measured by the method. They followed up with a study published in 2015 where they tried to gauge the method's long-term efficacy by examining children at 6 years of age, 2 years after the ESDM had ended. By comparing one group that had received traditional methods of treatment with another group receiving the ESDM treatment starting at between 18 and 30 months of age, they found no significant differences between the groups in core autism symptoms immediately after treatment ended (at 4 years of age); the ESDM group did show, however, significant improvements in core autism symptoms after 2 years, implying that the benefits of the treatment at a younger age affect developmental traits that only become noticeable in later stages of development. This was the first study that analyzed the efficacy of ESDM treatment starting at an age younger than 30 months.
Meta-analyses and systematic reviews have shown that the ESDM is promising. A meta-analysis of 12 individual studies with a total of 640 children published in 2020 concluded that, compared to control groups receiving traditional forms of treatment, children receiving the ESDM showed significant improvements in cognition and language abilities (G-test numbers of 0.412 and 0.408, respectively). A separate meta-analysis using 11 studies described as high-quality randomized controlled trials analyzed results in four major domains related to ASD (autism symptoms, language, cognition, and social communication). The study found that children receiving the ESDM showed significant improvements in the cognition (g = 0.28), autism symptoms (g = 0.27), and language (g = 0.29) domains.
Usage in countries
The diagnosis of autism has undergone significant changes in recent decades, which means the forms of treatment have also changed. Therefore, countries have incorporated treatment options in heterogeneous ways, meaning that the Denver Model has been adopted with different intensities throughout the world. The list below presents a brief description of how each country's healthcare system (public or private) deal with this form of treatment:
Australia
The National Disability Insurance Scheme of the Australian government recognizes the ESDM as a form of "naturalistic developmental behavioural intervention" with enough scientific evidence to support it, and will cover the costs of treatment and parent-training sessions if the child is eligible for this type of treatment.
Brazil
The Agência Nacional de Saúde Suplementar (ANS), Brazil's regulating body for private healthcare plan providers, recognizes different forms of ASD within the scope of pervasive developmental disorders. It lists ESDM as one of the forms of treatment that should be taken into consideration by healthcare providers for children with developmental disorders. Since July 1, 2022, healthcare providers are obligated to provide the form of treatment prescribed by the child's doctor, and this includes the ESDM.
France
Since 2012, the Haute Autorité de Santé of France recognizes ESDM's efficacy and recommends that public healthcare institutions consider it as one of their options when treating children with ASD.
United States
All 50 states in the USA have legislation requiring the coverage of autism spectrum treatments by private health insurance companies. The Centers for Disease Control and Prevention (CDC) includes the ESDM as a developmental approach in the treatment of ASD.
A study of applying the ESDM at an early age was conducted to assess the cost-effectiveness of applying the ESDM at an early age rather than using the traditional methods of treatment at later stages. The study indicates that the average increased cost of treatment at younger ages was significantly smaller than the total savings in treatments at older ages, with children needing fewer sessions of ABA/EIBI, occupational, physical and speech therapy services.
References
Behavior analysis
Behavior
Behavior modification
Behavioral concepts
Treatment of autism | Early Start Denver Model | [
"Biology"
] | 1,453 | [
"Behavior",
"Behavioral concepts",
"Behavior modification",
"Behaviorism",
"Human behavior"
] |
72,839,318 | https://en.wikipedia.org/wiki/Tecno%20Phantom%20X2 | Tecno Phantom X2 and Tecno Phantom X2 Pro are Android-based smartphones manufactured, released and marketed by Tecno Mobile as part of the phantom sub-brand. The devices were unveiled during an event held on 20 January 2023 as successors to Tecno Phantom X.
The Phantom X2 and Phantom X2 Pro is an upgraded version of Phantom X, coming with different features, including the OS, camera, design and battery. The phone has received generally favorable reviews, with critics mostly noting the performance, bigger battery and fast charging capacity.
Design
The Phantom X2 and Phantom X2 Pro come with the same design. The phones are fitted with a glass back and a front glass that is covered by Gorilla Glass Victus and an aluminum frame. Both devices come with a camera module that is placed centrally on the rear cover. The display of both phones features a punch hole placed centrally for the front camera.
Specifications
Hardware
Chipsets
Both devices utilize the MediaTek Dimensity 9000 system-on-chip.
Display
Both devices feature an AMOLED display with 1080p support and a display size of 6.8-inches. They utilize an optical in-screen fingerprint sensor. The devices have a curved-edge display with an OLED panel and support a 120 Hz refresh rate. They feature a 1080 × 2400 resolution with a 20:9 aspect ratio.
Storage
The Phantom X2 offers 4/8 GB of RAM, while the Phantom X2 Pro offers 4/12 GB of RAM. Both devices come with 64/128/256 GB of internal storage and lack a microSD card slot.
Battery
The devices contain a non-removable 5160 mAh Li-Po battery, supporting wired charging over USB-C at up to 45W.
Connectivity
The phones support 5G network, Wi-Fi 802.11 and Bluetooth 5.3.
Cameras
The Phantom X2 has a 64 MP wide sensor, a 13 MP ultrawide sensor and a 2 MP depth sensor, while the Phantom X2 Pro has a 50 MP wide sensor, a 13 MP ultrawide sensor and a 50 MP telephoto sensor with 2.5x optical zoom and a retractable lens. The front-facing camera of both devices uses a 32 MP sensor.
Supported video modes
The Tecno Phantom X2 series supports the following video modes:
4K@30/60fps
1080p@30/60fps
Software
Both devices run on Android 12 based software overlay HiOS 12 at launch, and come bundled with a slew of apps like IDA Engine 3.0, Aurora Engine, Ella 2.0 and Welife among others.
Reception
Harish Jonnalagadda from Android Central awarded the Phantom X2 Pro 3.2 stars out of 5, noting that the device "gets a lot right on the hardware side of things". Praise was directed towards the design, operating system, back camera with retractable portrait lens and battery. However, the software lack of refinement was criticized, while noting that "the phone will not get platform updates on time".
Adam Z. Lein from Pocketnow praised the Phantom X2 Pro for its camera, while noting that the device is "a nice entry into the competition as TECNO's flagship".
My Mobile India awarded the Phantom X2 4.5 stars out of 5, noting that the device "is a worthy example with which the company hopes to branch out into flagship territory".
Tech Arena24 praised the Phantom X2 Pro for its camera sensors and Gorilla Glass Victus protection. However, the lack of IP68 water and dust resistance rating, OIS stabilization, wireless charging, HDR10+, Dolby Vision, a brighter screen and up to three years of software update plan were criticized.
Oscar Frank praised the Phantom X2 Pro for its design, camera and processor while noting that the device is a "super smartphone from Tecno, if not the best they have to date". He however criticized the device for its speaker and microphone.
References
Android (operating system) devices
Phablets
Mobile phones introduced in 2022
Tecno smartphones | Tecno Phantom X2 | [
"Technology"
] | 851 | [
"Crossover devices",
"Phablets"
] |
72,839,347 | https://en.wikipedia.org/wiki/Leaky%20Acres%20Recharge%20Facility | The Leaky Acres Recharge Facility is a groundwater recharge facility located in Fresno, California. The facility began as a joint research project by the City of Fresno water division and the US Department of Agriculture. It first began percolating water in 1971 and was subsequently expanded and duplicated in other areas of the city.
History
Following years of population growth and installing wells to meet domestic water demands, the city of Fresno saw falling groundwater levels at their wells. In 1960, the average-depth-to-water was 68 feet, while in 1978 it was 81 feet. These falling water levels under the urbanized area stood in contrast to the rising water levels around the wastewater treatment plant located outside the city to the southwest, which received and disposed of the bulk of the stormwater flow.
A research project was begun with the intent to artificially recharge the aquifer using stormwater and other surface water, sending it under the urbanized area and hopefully lift groundwater levels. Fresno water division superintendent Charles Gorham worked with local United States Department of Agriculture station leader William Bianchi to develop a 117-acre groundwater recharge basin in central Fresno which they called "Leaky Acres".
They located the basin at Chestnut and Dakota Avenues, next to the Fresno International Airport. The experiment first began percolating water in 1971 and saw 0.7 of water per acre per day sink into the soil over a 4-month period. They reported their findings in 1972 and converted operations from an experiment to a permanent facility. There were early concerns about mosquitos and midges spawning in basins but some mitigation measures were put in place.
USDA station leader Bianchi wrote a technical report about the project which was selected as best paper of 1974 by the American Water Works Association. The association commended Bianchi for the successful project and for providing an example for other municipalities to solve groundwater recharge challenges.
An expansion adding approximately 70 acres to the facility was completed in 1979. Other agencies, such as the Fresno Irrigation District and the Fresno Municipal Flood Control District, built their own groundwater recharge facilities. The total construction and land costs for the expanded facility was $1,457,100.
Design
Leaky Acres has 117 acres of ponding surface in 10 basins. The basins are designed to speed up the process of water soaking into the ground. Drainage tile was placed five feet underground forming a type of French drain system. The water from the drainage tile flows into a well shaft which allows it to bypass soil layers which are not very permeable and into the aquifer.
Water is delivered from the Kings River to the facility headworks by the Fresno Irrigation District via the Gould Canal.
The effectiveness of the groundwater recharge through the soil was studied from 1971 to 1980. Over that period, the average recharge rate was 10,848 acre feet per year at 86 percent facility efficiency. The 10-year mean actual recharge rate based on actual water delivered, total ponded area, and total days of recharge was 4.7 inches per day.
References
Hydraulic engineering
Hydrology
Infrastructure
Water in California | Leaky Acres Recharge Facility | [
"Physics",
"Chemistry",
"Engineering",
"Environmental_science"
] | 637 | [
"Hydrology",
"Physical systems",
"Construction",
"Hydraulics",
"Civil engineering",
"Environmental engineering",
"Hydraulic engineering",
"Infrastructure"
] |
72,840,701 | https://en.wikipedia.org/wiki/V1334%20Cygni | V1334 Cygni, also referred to as ADS 14859 and HR 8157 in astronomical literature, is a star about light years from the Earth in the constellation Cygnus. It is a 5th magnitude star, which will be faintly visible to the naked eye of an observer located far from city lights. It is a classical Cepheid variable star, ranging in brightness from magnitude 5.77 to 5.96 over a period of 3.332816 days. V1334 Cygni is an important calibrator for models of Cepheid variables, because its presence in triple star system with a close binary pair has allowed its distance to be measured geometrically with 1% accuracy.
V1334 Cygni was discovered to be a double star in November of 1886, by George Hough using the 18.5 inch refractor at the old (Chicago) site of the Dearborn Observatory. It was given number 286 in his catalog. In the fall of 1966, V1334 Cygni was discovered to be a variable star accidentally, when Robert Mills used it as a presumed constant-brightness comparison star in a search for Cepheid variables. Follow-up observations by Mills in 1968 at Lowell Observatory found that the star showed "cepheid-like" brightness changes with a period of 3.335 days. It was given the variable star designation V1334 Cygni in 1970. In 2000, Nancy Evans deduced from radial velocity measurements that the star is actually a triple star system, with a close binary pair (containing the Cepheid variable) forming one "star" (component A) of the double star that had been identified more than a century earlier.
Attempts to identify component B (the companion star first seen by Hough in 1886) in the late 20th and early 21st centuries have been largely unsuccessful. This is surprising, because the speckle interferometry techniques employed by these later studies have far higher resolution than did Hough's refractor. But there are possible orbits for B which would be consistent with both a real 19th century detection and the non-detections a century later. There are doubts over whether a third star exists at all.
References
Cygnus (constellation)
105269
203156
Durchmusterung objects
Cygni, V1334
8157
Classical Cepheid variables
F-type bright giants
B-type main-sequence stars | V1334 Cygni | [
"Astronomy"
] | 494 | [
"Cygnus (constellation)",
"Constellations"
] |
72,841,600 | https://en.wikipedia.org/wiki/List%20of%20early-diverging%20flowering%20plant%20families | There are 27 families of flowering plants whose earliest ancestors diverged from what became the two most prominent groups of flowering plants, the eudicots and monocots. They are quite diverse, with woody and non-woody plants, evergreen and deciduous shrubs and trees, and plants that grow in soil, in water and on other plants.
Victoria amazonica has the largest undivided leaf of any plant, up to in diameter. The parasitic genera Hydnora and Prosopanche are the only flowering plants with no evidence of leaves or scales. Myristica fragrans, the source of nutmeg, was important in the 17th-century spice trade. Amborella may represent the earliest-diverging order of flowering plants.
Glossary
From the glossary of botanical terms:
annual: a plant species that completes its life cycle within a single year or growing season
basal: attached close to the base (of a plant or an evolutionary tree diagram)
herbaceous: not woody; usually green and soft in texture
perennial: not an annual or biennial
scale: a reduced leaf or a flattened outgrowth
woody: hard and lignified; not herbaceous
The APG IV system, the fourth in a series of plant taxonomies from the Angiosperm Phylogeny Group, places the early-diverging families in nine orders. Canellales, Laurales, Magnoliales and Piperales are grouped together as the magnoliid orders, with Chloranthales as a sister group. Amborellales, Nymphaeales and Austrobaileyales are the basal angiosperms or the ANA grade. Ceratophyllales may have been the last of the nine orders to diverge, but some fossil evidence links it to the older order Chloranthales.
Families
See also
List of plant family names with etymologies
Notes
Citations
References
See the Creative Commons license.
See their terms-of-use license.
Systematic
Early-diverging flowering plant families
Early-diverging flowering plant families
early-diverging flowering plant families | List of early-diverging flowering plant families | [
"Biology"
] | 422 | [
"Lists of biota",
"Lists of plants",
"Plants"
] |
72,842,129 | https://en.wikipedia.org/wiki/S/2016%20J%204 | S/2016 J 4 is a small outer natural satellite of Jupiter discovered by Scott S. Sheppard on 9 March 2016, using the 6.5-meter Magellan-Baade Telescope at Las Campanas Observatory, Chile. It was announced by the Minor Planet Center on 24 January 2023, after observations were collected over a long enough time span to confirm the satellite's orbit.
S/2016 J 4 is part of the Pasiphae group, a dispersed cluster of distant retrograde irregular moons of Jupiter that follow similar orbits to Pasiphae at semi-major axes between , orbital eccentricities between 0.2–0.6, and inclinations between 140–160°. It has a diameter of about for an absolute magnitude of 17.3, making it one of Jupiter's smallest known moons.
References
Pasiphae group
Moons of Jupiter
Irregular satellites
20160309
Discoveries by Scott S. Sheppard
Moons with a retrograde orbit | S/2016 J 4 | [
"Astronomy"
] | 193 | [
"Astronomy stubs",
"Planetary science stubs"
] |
72,845,151 | https://en.wikipedia.org/wiki/Kenneth%20T.%20Gillen | Kenneth T. Gillen is a retired Sandia National Labs researcher noted for contributions to service life prediction methods for elastomers
Education
Gillen completed his PhD in chemistry at University of Wisconsin - Madison in 1970 under advisor Joseph H. Noggle.
Career
Gillen joined Sandia National Labs in 1974, working on elastomeric seals in nuclear weapons and satellites. His research has focused on the prediction of the service life of polymers under exposure to temperature, radiation, humidity and mechanical stress. His most highly cited published work was the development of testing and analysis methods for the combined effects of diffusion and oxidation in polymers. His methods overcame limitations of earlier, less accurate methods based on the Arrhenius equation. His development of a technique for profiling of oxidation-induced stiffness gradients in aged elastomers was applied in the tire industry.
Gillen served as an editor of the Elsevier journal Polymer Degradation and Stability from 1999 to 2006.
He retired from Sandia in 2004 but continued in a part time consulting role until 2015.
Awards
2020 - Melvin Mooney Distinguished Technology Award from Rubber Division of the ACS
References
Polymer scientists and engineers
Living people
Year of birth missing (living people) | Kenneth T. Gillen | [
"Chemistry",
"Materials_science"
] | 243 | [
"Polymer scientists and engineers",
"Physical chemists",
"Polymer chemistry"
] |
72,850,413 | https://en.wikipedia.org/wiki/Porphyrellus%20formosus | Porphyrellus formosus, the dark velvet bolete, is a species of bolete fungus in the family Boletaceae, first described as Tylopilus formosus by Greta Stevenson in 1962, and moved to Porphyrellus genus in 2014 by J. A. Cooper.
It is endemic to New Zealand, forming mycorrhiza with southern beeches and mānuka. It's distinguishing feature is all-black and velvety surface of cap and stalk. It initially has white pores that turn golden when aged.
References
formosus
Fungi of New Zealand
Fungi described in 1962
Fungus species | Porphyrellus formosus | [
"Biology"
] | 127 | [
"Fungi",
"Fungus species"
] |
72,851,094 | https://en.wikipedia.org/wiki/Scythian%20genealogical%20myth | The Scythian genealogical myth was an epic cycle of the Scythian religion detailing the origin of the Scythians. This myth held an important position in the worldview of Scythian society, and was popular among both the Scythians of the northern Pontic region and the Greeks who had colonised the northern shores of the Pontus Euxinus.
Narrative
Five variants of the Scythian genealogical myth have been retold by Greco-Roman authors, which all traced the origin of the Scythians to the god Targī̆tavah and to the Scythian Snake-Legged Goddess:
Herodotus of Halicarnassus's recorded two variants of the myth, and according to his first version, one thousand years before the Scythians were invaded by the Persians in 513 BC, the first man born in hitherto desert Scythia was named Targitaos and was the son of "Zeus" (that is the Scythian Sky-god Pāpaya) and a daughter (that is the Scythian Earth-goddess Api) of the river Borysthenēs. Targitaos in turn had three sons, who each ruled a different part of the kingdom, named:
Lipoxais (; )
Arpoxais (; )
Kolaxais (; )
One day three gold objects – a battle-axe, a plough with a yoke, and a drinking cup – fell from the sky, and each brother in turn tried to pick the gold, but when Lipoxais and Arpoxais tried, it burst in flames, while the flames were extinguished when Kolaxais tried. Kolaxais thus became the guardian of this sacred gold (the of Tāpayantī), and the other brothers decided that he should become the high king and king of the Royal Scythians while they would rule different branches of the Scythians.
Kolaxais in turn had three sons who each ruled a part of the Scythian kingdom.
According to the second version of the myth recorded by Herodotus, Hēraklēs arrived in deserted Scythia with Gēryōn's cattle. Because of the extremely cold weather of Scythia, Hēraklēs covered himself with his lion skin and went to sleep. When Hēraklēs woke up, he found that his mares had disappeared, and he searched for them until he arrived at a land called the Woodland (; ), where in a cave he found a half-maiden, half-viper being who later revealed to him that she was the mistress of this country, and that she had kept Hēraklēs's horses, which she agreed to return them only if he had sexual intercourse with her. She returned his freedom to Hēraklēs after three sons were born of their union:
Agathyrsos (; )
Gelōnos (; )
Skythēs (; )
Before Hēraklēs left Scythia, the serpent maiden asked him what should be done once the boys had reached adulthood, and he gave her his girdle and one of his two bows, and told her that they should be each tasked with stringing the bow and putting on the girdle in the correct way, with whoever succeeded being the one who would rule his mother's land while those who would fail the test would be banished. When the time for the test had arrived, only the youngest of the sons, Skythēs, was able to correctly complete it, and he thus became the ancestor of the Scythians and their first king, with all subsequent Scythian kings claiming descent from him. Agathyrsos and Gelōnos, who were exiled, became the ancestors of the Agathyrsoi and Gelōnoi.
A third variant of the myth, recorded by Gaius Valerius Flaccus, described the Scythians as descendants of Colaxes (), who was himself a son of the god Iūpiter with a half-serpent nymph named Hora.
The version of the myth recorded by Gaius Valerius Flaccus suggests that Herodotus's first version of the Scythian genealogical myth might have ended with Lipoxais and Arpoxais murdering Kolaxais.
The fourth variant of the myth, recorded by Diodorus of Sicily, calls Skythēs the first Scythian and the first king, and describes him as a son of "Zeus" and an earth-born viper-limbed maiden.
The fifth version of the myth, recorded in the , recorded that after Hēraklēs had defeated the river-god Araxēs, he fathered two sons with his daughter Echidna, who were named Agathyrsos and Skythēs, who became the ancestors of the Scythians.
Among the two versions of the genealogical myth recorded by Herodotus of Halicarnassus, the first one was the closest to the original Scythian form, while the second one was a more Hellenised version which had been adapted to fit Greek mythological canons.
Some regional variations of the genealogical myth might have existed in Scythia, including possibly one which placed the setting of the myth near the mouth of the Tyras river, at the location of the city of Tyras, which was initially called "the snake-filled" () by the Greeks, possibly because the local inhabitants claimed that the home of the serpent-legged Scythian ancestral goddess was located there rather than at Hylaea.
The myth of the golden objects which fell from the sky was also present among other Scythic peoples such as the Saka of Central Asia, and therefore must have been an ancient Iranian tradition.
Interpretation
The Snake-Legged Goddess
The serpent-mother's traits are consistent across the multiple versions of the genealogical myth and include her being the daughter of either a river-god or of the Earth and dwelling in a cave, as well as her being half-woman and half-snake. The Scythian foremother was also an androgynous goddess who was often represented in art as being bearded.
The Snake-Legged Goddess was thus a primordial ancestress of humanity, which made her a liminal figure who founded a dynasty, and was therefore only half-human in appearance while still looking like a snake, itself being a creature capable of passing between the worlds of the living and of the dead with no hindrance.
The snake aspect of the goddess is linked to the complex symbology of snakes in various religions due to their ability to disappear into the ground, their venom, the shedding of their skin, their fertility, and their coiling movements, which are associated with the underworld, death, renewal, and fertility: being able to pass from the worlds above and below the earth, as well as of bringing both death and prosperity, snakes were symbols of fertility and revival. The legs of the goddess were sometimes instead depicted as tendrils, which also had a similar function by representing fertility, prosperity, renewal, and the afterlife because they grow from the Earth within which the dead were placed and blossom again each year.
The Snake-Legged Goddess was also a feminine deity who appeared in an androgynous form in ritual and cult, as well as in iconography and ritual. This androgyny represented the full inclusiveness of the Snake-Legged Goddess in her role as the primordial ancestress of humanity. The androgyny of the Snake-Legged Goddess also enhanced her inherent duality represented by her snake and tendril limbs.
The role of the Snake-Legged Goddess in the genealogical myth is not unlike those of sirens and similar non-human beings in Greek mythology, who existed as transgressive women living outside of society and refusing to submit to the yoke of marriage, but instead chose their partners and forced them to join her. Nevertheless, unlike the creatures of Greek myth, the Scythian serpent-maiden did not kill Hēraklēs, who tries to win his freedom from her.
The identification of the father of the Snake-Legged Goddess with the river-god Araxes corresponds to the non-mythological origin of the Scythians as recorded by Herodotus of Halicarnassus, according to which the Scythians initially lived along the Araxes river until the Massagetae expelled them from their homeland, after which they crossed the Araxes river and migrated westwards.
The myth of Aphroditē Apatouros
The Scythian genealogical myth was a continuation of the legend of () and the Giants as recorded by Strabo, according to which the goddess Aphroditē Apatouros had been attacked by Giants and called on Hēraklēs for help. After concealing Hēraklēs, the goddess, under guise of introducing the Giants one by one, treacherously handed them to Hēraklēs, who killed them. Aphroditē Apatouros and "Hēraklēs" then buried the Giants under the earth, due to which volcanic activity remained a constant in the region of Apatouron.
Aphroditē Apatouros was the same goddess as the Snake-Legged Goddess of the Scythian genealogical myth, while "Hēraklēs" was in fact Targī̆tavah, and her reward to him for defeating the Giants was her love.
The Greek poet Hesiod might have mentioned this legend in the , where he assimilated the Snake-Legged Goddess to the monstrous figure of Echidna from Greek mythology. In Hesiod's narrative, "Echidna" was a serpent-nymph living in a cave far from any inhabited lands, and the god Targī̆tavah, assimilated to the Greek hero Hēraklēs, killed two of her children, namely the Hydra of Lerna and the lion of Nemea. Thus, in this story, "Hēraklēs" functioned as a destroyer of evils and a patron of human dwellings located in place where destruction had previously prevailed.
"Hēraklēs"
The "Hēraklēs" of Herodotus of Halicarnassus's second version and from the 's version of the genealogical myth is not the Greek hero Hēraklēs, but the Scythian god Targī̆tavah, who appears in the other recorded variants of the genealogical myth under the name of Targitaos or Skythēs as a son of "Zeus" (that is, the Scythian Sky Father Papaios), and was likely assimilated by the Greeks from the northern shores of the Black Sea with the Greek Hēraklēs because of his important role in the foundational myths of the Greek colonists throughout the Mediterranean basin.
The arrival of "Hēraklēs" in the deserted Scythia corresponds to the mythical motif of the conquest of the empty land by the brave invader, while the stealing of his mares by the serpent maiden corresponds to the cattle-raid motif of Indo-Iranic mythology.
The reference to "Hēraklēs" driving the cattle of Gēryōn also reflects the motif of the cattle-stealing god widely present among Indo-Iranic peoples, and the reference to him stealing Gēryōn's cattle after defeating him in Herodotus of Halicarnassus's second version of the genealogical myth and of his victory against the river-god Araxēs in the 's version were Hellenised versions of an original Scythian myth depicting the typical mythological theme of the fight of the mythical ancestor-hero, that is of Targī̆tavah, against the chthonic forces, through which he slays the incarnations of the primordial chaos to create the Cosmic order.
The Hellenised myth of Targī̆tavah staying in Scythia might have been recorded in the , which mentions a bull-riding cattle-thief Titan, who, in this Hellenised narrative, might have been "Hēraklēs," to whom Targī̆tavah was identified, and who created the Cimmerian Bosporus by cutting a passage from the Maeotian swamp.
The stolen horses and the bow of Targī̆tavah in the second variant of the genealogical myth connected him to the equestrianism and archery of the Scythians.
The peoples of Scythia believed that Targī̆tavah had left a two-cubit long footprint in the territory of the Tyragetae, in the region of the middle Tyras river, which the local peoples of this area displayed proudly. Since only gods were able to leave footprints on the hard rock, this footprint was held as a sign of divine protection, and, being the ancestor of the Scythians, he became their protector and laid claim to their country and all of its inhabitants for eternity by pressing his footprint into the Scythian rock.
Targī̆tavah might also have been identified by the Greeks in southern Scythia with Achilles Pontarkhēs (), in which role he was associated with the Snake-Legged Goddess and was the father of her three sons.
Cosmogenesis
This myth explained the origin of the world, and therefore begun with the Heaven father Pāpaya and the Earth-and-Water Mother Api being already established in their respective places, following the Iranic cosmogenic tradition. This was followed by the process of creation proper through the birth of the first man, Targī̆tavah.
Ethnogenesis
The Scythian genealogical myth also ascribed the origin of the Scythians to the Scythian Sky Father Papaios, either directly or through his son Targī̆tavah, and to the Snake-Legged Goddess affiliated to Artimpasa, and also represented the threefold division of the universe into the Heavens, the Earth, and the Underworld, as well as the division of Scythian society into the warrior, priest, and agriculturalist classes.
The desert
The original deserted state of the land of Scythia when Targī̆tavah first arrived there in the myth followed the motif of the primordial state of the land, which was devastated and barren before the first king finally ended this state of chaos by establishing the tilling of the land and the practice of agriculture. One of the themes of both Herodotean versions of the Scythian genealogical myth as well as of the other Scythian origin myth known as the "Polar Cycle" is that of the Scythians' occupation of the virgin land.
The sons of Targī̆tavah
Lipoxais, Arpoxais, and Kolaxais
The names of Targī̆tavah's sons in the first version of the genealogical myth – Lipoxais, Arpoxais, and Kolaxais – end with the suffix "," which is a Hellenisation of the Old Iranian term meaning ruler:
Lipoxais, from Scythian , from an earlier form , means "king of radiance," in the sense of "king of the sun."
The first element, , is derived from the Indo-European root , meaning "to be bright" a well as "sky" and "heaven," and can also give the name the meaning of "king of heaven."
Arpoxais, from Scythian , means "king of the skillful" and "king of the toilers," as well as "king of the airspace."
The element might have been a cognate of the Sanskrit term (), which is the name of a group of Indic deities of the airspace.
Kolaxais, from Scythian , means "poleaxe-wielding king" or "hammer-wielding king," as well as "sceptre-wielding king," "thunderer king," and "blacksmith king," with the latter meaning "ruling king of the lower world."
The layers of the cosmos
The names of the three sons of Targī̆tavah therefore corresponded to the three layers of the cosmos:
Lipoxšaya was the "King of Radiance," and therefore of the Heavens;
R̥buxšaya was the King of the Airspace, and therefore of lightning;
Kolaxšaya was the Poleaxe/Hammer/Sceptre-wielding King and the Thunderer and Blacksmith king, and therefore of the Lower World.
Progenitors of the social classes
The genealogical myth also represented the formation of the three social classes of Scythian society, namely the warrior-aristocracy, the clergy, and the peasantry, with each of the sons of Targī̆tavah being forebears of social classes constituting the Scythian people:
Lipoxšaya was the ancestor of the Aukhatai (; );
The original Scythian form of the Hellenised name might have been , meaning "the blessed ones" or "the holy ones."
R̥buxšaya was the ancestor of the Katiaroi (; ) and the Traspies (; );
The original Scythian form of might have been derived from , meaning "three horses."
The original Scythian form of the Hellenised name might have been , meaning "possessors of cattle pastures";
Kolaxšaya was the ancestor of the Paralatai (; ), also known as the Royal Scythians, who were the warrior-aristocracy of the Scythians.
The name was a Greek reflection of the Scythian name , which was a title held by the Scythian warrior-aristocracy to which the kings belonged, with the kings being members of the Paralāta, although not all the Paralāta were kings. The name Paralāta was a cognate of the Avestan title (), which means "first created."
The three sons of Targī̆tavah represented the division of Scythian society into a system of tripartite classes which existed among all the Indo-European peoples, and is well-attested among the Indo-Iranic peoples, such as the three-fold class system of Zoroastrianism, as well as the system of the Indic peoples which divided the societies of the Indic peoples into the clerical class of the , the military aristocracy of the to which belonged the warriors and kings, and the wealth-producing ordinary community members of the .
These three classes, in turn, each corresponded to the typically Indo-Iranic tripartite structure of the universe of Scythian cosmology, which is also present in the Vedic and Avestan traditions, and according to which the universe was composed of the heavens, the airspace, and the earth.
The three sons of Targī̆tavah were thus ancestors of the various social classes of Scythian society who also represented the three levels of the Cosmos: the upper celestial realm, the middle sphere of the airspace, and the lower terrestrial world, with the central son representing the airspace linking the two others, which also parallels the roles of the Sky Father Papaios, the Earth-and-Water Mother Api, and their child, Targī̆tavah, that is the airspace.
The warrior class
The Scythian genealogical myth thus assigned to the Scythian kings a divine ancestry through descent from Kolaxšaya, as attested when the Scythian king Idanthyrsus claimed Papaios as his ancestor. The name was a Greek reflection of the Scythian name , which was a title held by Scythian kings, and was also a cognate of the Avestan title (), which means "first created."
According to the version of the genealogical myth recorded by Gaius Valerius Flaccus, Kolaxšaya and his warriors decorated their shields with "fires divided into three parts," flashing lightning, and pictures of red wings, with the colour red being characteristic of the warrior class in Indo-Iranic tradition.
The priestly class
In Gaius Valerius Flaccus's narrative, Auchus, that is Lipoxšaya, was born with white hair and wore a band which passed around his head three times and whose ends hanged backwards, with the colour white in Indo-Iranic tradition being that of priesthood, and the headband of Auchus being part of a priest's regalia which was depicted in the art of the various ancient Iranian peoples. These thus signalled Lipoxšaya as the progenitor of Aukhatai, that is the priestly component of Scythian society's tripartite class system.
The farmer class
R̥buxšaya, meanwhile, was the progenitor of the Katiaroi and Traspies, who formed the third section of the Scythian class system, that of the ordinary populace consisting of farmers and horse-breeders.
The sub-division of the farmer class into two groups, namely the Katiaroi connected to cattle the Traspies connected to horses, fits an Indo-Iranic motif of which the other iterations include the Zoroastrian Gə̄uš Uruuan (whose name means "the soul of the cow") and Druuāspā (whose name means "(the deity) with healthy horses"), as well as the Vedic Aśvins and their sons in later Hindu tradition, Nakula and Sahadeva. The name of the Traspies, likely derived from Scythian , meaning "three horses," is also semantically connected to that of the Aśvins.
The gold objects and the class structure
The three golden objects which fell from the sky also represented the various Scythian classes:
the battle-axe represents the warrior-aristocracy;
the battle-axe also functioned as a royal sceptre or staff
the cup, used during religious rituals for offering libations and to prepare , representing the priestly class;
the plough used by farmers to till the fields and the yoke associated with cattle-breeding represented the lowest class of the Katiaroi and Traspies.
The golden objects, that is the of Tāpayantī, as attested by their fiery nature, were the fires of the three classes of Scythian society, with the triunity of the Scythian representing the concept of fire, represented by the goddess Tāpayantī, being the primeval and all-encompassing element permeating the world and being present throughout it.
Although each of the three gold objects each corresponded to one of the three layers of the Scythian tripartite class structure, the fact that they all came into the possession of Kolaxšaya and his descendants meant that they had no connections to his elder brothers who also corresponded to two of the three Scythian social classes.
The plough-and-yoke and the cup, although representing the farmer and priestly functions, were instead symbols of royal power used in the coronation rites of the Scythian king, which themselves found a parallel in the consecration ceremony of Indic kings. The acquisition of the objects by Kolaxšaya represented the Scythian royal coronation ritual, according to which the world order was disturbed by the death of the previous king and was restored through the coronation of the new king.
The falling of the three objects from the sky and Kolaxšaya coming to possessing them was also a myth of the transfer of power from the older generation of gods to the newer one, similar to power leaving Ouranos in ancient Greek religion and Varuṇa in ancient Vedic religion to pass on to the newer generations.
Kingship
Kingship and the
The Scythian genealogical myth was a variant of an old Indo-European tradition present among the Indo-Iranic peoples, especially those who were part of the steppe cultures, according to which the royal dynasty and, by extension, the nation itself, were born from the union of a serpent-nymph and a travelling hero who was searching for his stolen horses. This motif became widely widespread in the region of the Caucasus.
Therefore, the ownership of the three golden objects which fell from the sky, which constituted the of Tāpayantī, by Kolaxšaya and his descendants constituted a heaven-given manifestation of divine origin of the royal power of the Scythian kings, and of the kings' proximity to Tāpayantī. The Scythian goddess Tāpayantī was herself linked to the , and the ownership of her thus provided to Kolaxšaya the (), that is the royal splendour, which among Iranic peoples was believed to transform the king into a sacred figure and a kind of deity who was sometimes believed to be the brother of the Sun and the Moon. Among the Scythic peoples, this notion of the association of the Sun with kingship was attested by the Massagetaean practice of sacrificing horses to the Sun-god.
The importance of the among the many Scythic peoples is attested by the fact that it is the most widespread element among recorded Scytho-Sarmatian names in the Pontic Steppe region.
The of Tāpayantī were thus the physical manifestations of the and were guarded by the kings, with this association being evident in how the golden objects burnt the brothers who were unworthy of kingship, but did not harm the legitimate king, Kolaxšaya. Like the typically Iranic conceptions of the attested in the Zoroastrian and Persian myths, the Scythian was of heavenly origin, and represented an emanation of the sacred fire, and therefore could be itself depicted as objects made of or decorated with gold. It was the who chose the king, legitimised him, and guaranteed his power, while the king himself was seen as being unable of being burnt like fire.
The Scythian concept of the was thus tripartite, with all of its three components belonging together to the king, although they could leave the king if he became unworthy. The three components of the also represented an emanation of the celestial fire and each corresponded to one of the three social classes of Scythian society, and were worshipped in religious rites.
All Iranic peoples considered gold to be a symbol of and its material incarnation, as well as the metal of the warrior-aristocracy, with the ownership of the in the form of gold being necessary for a warrior to be victorious. Thus, the connection of the and gold with the king represented its connection to the warrior-aristocracy to which the kings belonged. In consequence, Iranic kings surrounded themselves with gold, which was supposed to help them preserve their , hence why Scythian kings only used gold cups, which represented the priestly role of royal power. Due to this, the cups placed in the burials of the earliest Scythian kings at were all made of gold.
Because the was believed to have a solar nature, and therefore to be dangerous and capable of harming ordinary humans, the Scythian kings avoided direct contact with members of the populace, and instead communicated with them through the means of royally-appointed messengers who were buried with the kings after their deaths.
Kingship and the social classes
At the same time, the Scythian physical form of the royal consisted of three objects which each represented one of the three social classes of Scythian society, with the king himself thus encompassing and transcending these classes.
The narrative of the ancestor of the Paralāta, Kolaxšaya, succeeding in acquiring the gold objects, that is the of Tāpayantī, which had fallen from the sky was also an explanation of the supremacy of the tribe descended from him, that is the Royal Scythians, over the other Scythian tribes, and of the Scythian kings, who bore the title of Paralāta. The ownership of the of Tāpayantī thus gave to Kolaxšaya the right to rule, and they also represented the king's role whereby, as the ruler of all society, he also represented all the social classes, being this the chief warrior, the chief priest, and the chief farmer, with all three social roles united within him.
This conceptualisation of the king originating from the warrior-aristocracy but at the same time encompassing the three social functions and representing all the classes by being himself the incarnation of society was one of the fundamental concepts of Indo-Iranic ideology. This practise was also present among the Indic peoples, where the king originated from the warrior aristocracy, and was proclaimed to be a member of the priestly caste and symbolically married the , and then did the same with the producer caste. Other Indic coronation rites also included the symbolic birth of the king from the and castes, thus becoming a member of all three castes at the same time. Although information about coronation rites among the Iranic peoples is meagre, this appears to have been the case among them too.
Thus, the passage of the Scythian genealogical myth regarding the three brothers explained how the three sons of Targī̆tavah represented the three social classes, with the youngest of the sons, Kolaxšaya, who was the warrior, also united within himself the function of all three classes. It also explained the dominant role of the warrior-aristocratic class over the other classes.
The version of the Scythian genealogical myth retold by Diodorus of Sicily also made the sons of Skythes the progenitors of the social classes:
the corresponded to the warrior class of the ,
the corresponded to the rest of the Katiaroi and Traspies.
Pliny the Elder recorded a Scythian myth, according to which a struggle between the and the resulted in the destruction of the latter by the former, representing the establishment of the supremacy of the warrior class over the producer class. Only the warrior and producer classes are mentioned in this myth because the priestly class was completely subordinate to the warrior aristocracy.
Kingship and institutions
The Scythian genealogical myth originated among the royalty, and was used by the Scythian kings to establish the divine origin of their kingship and their right to rule by virtue of being the descendants of Kolaxšaya. By asserting the supremacy of the youngest brother over the elder ones, the genealogical myth also assigned such a preeminence to the Scythians, who claimed to be the "youngest of all peoples."
The genealogical myth also ascribed to the Scythians' political and social institutions an antiquity dating back to the mythical era of the ancestors, which in the Scythian worldview was seen as ensuring the "correctness" of these institutions, which in turn guaranteed the stability and prosperity of Scythian society.
In the genealogical myth, Targī̆tavah, the first man born from the union of the Heavenly Father and the Earth-and-Water Mother, represented the primordial unity. This unity incarnated by Targī̆tavah soon underwent fragmentation on the levels of kinship due to Targī̆tavah having three sons, ethnicity and territory in the form of each son founding a different tribe, and class due to the three objects representing three social classes and their respective functions. This fragmentation was finally stopped when the three objects chose Kolaxšaya, who became king when he gained possession of the gold objects which formed the totality of kingship, and his brothers proved themselves to be unworthy of possessing them and therefore became subordinate to him and the peoples descended from them became subordinate to the descendants of Kolaxšaya.
After the loss of the primordial state of perfect unity, the gods sought to restore as much of this unity as feasible by choosing Kolaxšaya, who thus encompassed and reintegrated the fragmented elements of the primordial totality within himself by becoming king.
In consequence, the following Scythian kings kept the gold objects as both a royal and national treasure which acted as the symbol and legitimising source of their power and position, and which they had to renew each year through religious rituals to preserve the walfare and unity of the Scythians. Thus, priest-kings were in charge of restoring the lost primordial unity among the Scythians.
The sons of Kolaxšaya
The division of the Scythian kingdom between the three sons of Kolaxšaya transposed the Scythian three-fold cosmological structure and social structure composed of three classes onto the institution of Scythian kingship, and therefore also explained the division of Scythia into three kingdoms of which the king of the Royal Scythians was the High King. Thus, Scythia was ruled by three kings, of whom one was the supreme king who guarded the of Tāpayantī. This threefold kingship is a structure recorded in historical times in Herodotus's account of the Scythian campaign of the Persian king Darius I, when the Scythians were ruled by the three kings, namely Idanthyrsus, Skōpasis, and Taxakis, with Idanthyrsus being the Scythian high king while Skōpasis and Taxakis were sub-kings.
Kolaxšaya's partition of his kingdom among his three sons also explained the three-fold division of the Scythians into the three tribal groupings of the Royal Scythians, the Nomadic Scythians, and the Agricultural Scythians.
The horse of Kolaxšaya
The mention of a "horse of Kolaxšaya" () in a , recorded by Alcman and dedicated to Artemis Orthia or the Dioscuri, suggests that Kolaxšaya possessed an unruly and fabulous horse of a fiery nature which had a white coat. This horse might have been believed to be the ancestor of all war horses.
According to Valerius Flaccus's version of the genealogical myth, the horse of Kolaxšaya was killed by the Greek hero Jason, who then killed Kolaxšaya himself. This might reflect the passage of the Scythian genealogical myth where Kolaxšaya himself was murdered by his brothers.
Agathyrsos, Gelōnos, Skythēs
The sons of Targī̆tavah according to the second version of the genealogical myth were each also ancestors of tribes belonging to the Scythian cultures:
Agathyrsos was the ancestor of the Agathyrsoi,
Gelōnos was the ancestor of the Gelōnoi,
Skythēs was the ancestor of the Scythians proper, who were named after him.
Each of the sons of Targī̆tavah in the second version of the genealogical myth respectively corresponded to the sons from the first version, with Agathyrsos corresponding to Lipoxšaya, Gelōnos corresponding to R̥buxšaya, and Skythēs corresponding to Kolaxšaya.
The "horse of Kolaxšaya" from the of Alcman might alternatively have referred to Scythian horses in general due to the Scythians possibly being considered to be "Kolaxšaya-ians" because of the identification of Skythēs with Kolaxšaya.
The trial of the sons
The tasks which the sons of Targī̆tavah had to perform as trial in this second version of the genealogical myth consisted of stringing a bow, and strapping a tight belt to which was attached a cup.
The bow was a military tool, with a similar set of tools being attributes of the Indic , and it corresponded to the battle-axe which formed part of the of the first version of the genealogical myth. This bow was therefore used to find out which brother was the warrior and would therefore be the ancestor of the warrior class.
The belt with the cup attached to it was a sacerdotal tool, with the belt being associated to priests in Indo-Iranic tradition: adherents of Zoroastrianism had to start wearing the from a young age, attesting of the initiatic role of the belt; and the belt was also used in the initiation rites of the Indic priestly caste; therefore, the belt with a cup attacked to it represented the Scythian king's role as a priest. Thus, after having proven that he was a warrior, Skythēs also obtained the cup and therefore earned the right to perform priestly functions.
Herodotus claimed that the Scythians of his time still wore cups hanging from their belts in memory of Skythēs.
The trial of the sons of Targī̆tavah was a warrior's trial as well as a priest's trial through which Skythēs, as the king, united the social classes composing Scythian society within himself. Thus, Skythēs was the first king and the progenitors of the Scythian kings.
The possession of the bow of Targī̆tavah in the second version of the Scythian genealogical myth thus corresponded to the possession of the in the first version, and the function of both was to test the candidate for kingship, with these objects collectively symbolising power and the king's acquisition of them meaning that he passed the rest to become the ruler. The acquisition of the and the bow of Targī̆tavah therefore was part of the king's initiation ritual.
The belt with a cup attached to it was also a symbol of royal power in multiple Iranic traditions, and the cup itself was used in coronation rites among the many Indo-Iranic peoples, including the Scythians. Golden cups were also placed in the burials of deceased kings.
The cup and the arrows were elements of the Scythian coronation rituals, but they were also symbols of unity among the Scythians, as were the axe and spear, hence why whenever the Scythians concluded a treaty of friendship, they poured wine in a cup and lowered a sword, arrows, an axe, and a spear into it.
Similarly, in the story of the cauldron of Ariantas, each arrowhead represented a Scythian warrior individually, and the copper vessel standing at the Holy Ways which made from all of the arrowheads functioned as the ritual unification of the Scythians.
The arrows and the cup were thus symbols of royal power used in the coronation rites of the Scythian king, which themselves found a parallel in the consecration ceremony of Indic kings. The acquisition of these objects by Kolaxšaya represented the Scythian royal coronation ritual, according to which the world order was disturbed by the death of the previous king and was restored through the coronation of the new king.
The name of the Scythians
The second version of the Scythian genealogical myth also explained the origin of the name of the Scythians as being derived from that of Skythēs ( in Proto-Scythian; in Scythian), whose name meant "archer," and after whom the Scythians were called ( in Proto-Scythian), meaning "archers."
Hellenisation
The second version of the genealogical myth was one that had been Hellenised, which was not an uncommon practice of ancient Greeks done with the aim of including Barbarian peoples into the orbit of their own civilisation. Greek colonists who settled in remote peripheral regions often connected these new areas to their own myths, deities, and heroes by identifying Greek heroes with the local peoples' mythological forefathers.
In Greek mythology, Hēraklēs had killed the giant Gēryōn and seized his cows, after which he sailed from Gēryōn's home island of Erytheia to Tartēssos in Iberia, from where he passed by the city of Abdēra and reached Liguria, and then going south to Italy and sailing to Sicily: on the way, he founded several cities and settlements which the Greeks supposedly later "regained." The population of new territories with characters from Greek mythology and history was thus done to justify their acquisition, and therefore the Greeks turned Hēraklēs into a founder of various nations, dynasties, and cities throughout the Oikoumenē from Iberia to India, with these feats being described in several epic which were composed and enjoyed popularity within ancient Greek society.
These various stories relating Hēraklēs to various ancestral heroes of non-Greek peoples often followed the same narrative of Hēraklēs returning from Erytheia after defeating the giant Gēryōn and stealing his cattle before losing his animals due to them being stolen by an often monstrous figure, after which Hēraklēs had to reacquire his animals by challenging the thief. Within the context of the Scythian genealogical myth, such a story of Hēraklēs was transposed onto the narrative of the union with the snake-maiden so as to emphasise his differences with his Scythian children, while Hēraklēs himself left nothing but a footprint in Scythia.
The Hellenisation of the Scythian genealogical myth was, consequently, carried out probably by the Pontic Olbians to further their own interests among the Scythians. Therefore, the Iranic cosmological features such as the union of heaven and earth and the birth of the primordial unity represented by Targī̆tavah were ignored, and humanity as well as divisions in terms of gender, geography, status, and ethnicity had already come into existence. Therefore, version of the Scythian genealogical legend Hellenised by the Pontic Greeks featured one of the most prominent Greek heroes and took place following his adventure on the sunset island of Erytheia where lived Gēryōn.
Thus, the production of cultic propaganda for the Greek heroes and deities was done by the colonists to establish their own rights over the lands where they had settled, as well as over the areas around them and their non-Greek populations, and the figures of Hēraklēs and Achilles were important in this process among the Greeks of Olbia and Borysthenes, with Hēraklēs being made into a divine coloniser who civilised the three peoples of Scythia and becoming the father of their eponymous ancestors.
The Olbia-centricity of this variant of the myth is exhibited by the mention of Hylaea, which was close to Pontic Olbia, but also by how it constituted an explanation for the cult of Targī̆tavah-Hēraklēs there. Nevertheless, even this Hellenised myth still contained many Scythian elements which had equivalents in various Iranic traditions.
In this version of the myth, the snake legs of the mother goddess and her dwelling place within the earth marked her as a native of Scythia. The ambiguous features of the mother goddess, such as her being both human and animal, high-ranking and base, monstrous and seductive, at the same time, corresponded to Greek perceptions of Scythian natives. Therefore, although she ruled over the land, her kingdom was empty, cold, uninhabited, and without any signs of civilisation. Thus, her status was inferior to that of Hēraklēs in this version of the myth regarding her appearance as well as her role within the myth itself, where she followed the advice and instructions of Hēraklēs but did not decide anything.
The Hellenised myth contrasted the chthonic cave-dwelling goddess with the Olympian Hēraklēs, who used the sun-chariot of Helios to complete certain of his labours and to rise to the deities of the celestial realm, and also possessed the bow of Apollo, which had similar attributes.
Therefore, it was Hēraklēs, a Greek, who incarnated both the power of otherness and the otherness of power, arrived into Scythia from abroad to change the situation: in this Hellenised version of the myth, it was through union with Hēraklēs that the pre-civilised Scythia could be transformed into a world more familiar to the Greeks by the introduction of the institution of kingship.
Meanwhile, the chthonic Scythian ancestress was later identified by the Graeco-Romans with the monstrous figure of Echidna from Hesiod's whom this latter author had located in Cilicia, which was then at the boundaries of Hesiod's known world, and whom Herodotus later located at the boundaries of his own known world, in the cold lands of Scythia that were separated from civilised eyes by the cold.
Unlike the negative role of Echidna and of various snakes in Greek mythology, the partially serpentine anatomy of the "Scythian Echidna" denoted her connection with the earth, and therefore of her autochthony, and her theft of the mares of Hēraklēs was more akin to the jokes played on their lovers by beautiful maidens who were always forgiven. And unlike the stories where the animals of Hēraklēs were stolen by hostile enemies, the serpent maiden instead opposed the hero's civilising march and in the end obtained an ambiguous victory by permitting him to leave a permanent sign of his passage through the descendance he had with her.
Before Hēraklēs left Scythia, the mother goddess asked him whether she should settle them in her own land or send them to Hēraklēs once they have grown up, which was a way for her to ask whether the sons were to be Scythians (if they were to live with their mother) or Greeks (if they were to live with their father). Hēraklēs's response was to give them his bow, belt, and cup, which were instruments of culture, and declared that whoever among them would be able to string the bow and gird himself with the belt would become king.
However, Hēraklēs did not claim any of the children and instead instructed that the son who passed his test and therefore was the most like Hēraklēs himself would inherit Scythia, while the other less able brothers who were therefore less like Hēraklēs would be exiled to the north, in the direction opposite to Hēraklēs's destination in Greece.
The bow of Hēraklēs itself represented prosperity, wisdom, and life, and the trial he instructed the mother to put their sons through was meant to choose the most intelligent, skillful and strong one among them to be the king. His sacred union with the Scythian goddess also represented that of the friendly interactions of the Greeks with non-Greeks.
Therefore, the addition of Hēraklēs in the second version of the genealogical myth ascribed to the Snake-Legged Goddess's sons a partial Greek ancestry, with the most youngest son proving himself to be the most worthy due to him being more Greek than his brothers through his physical prowess inherited from his father; as well as him obtaining the bow, belt and cup, which were tools of Greek culture; moreover, his inheritance of Scythia meant that he was the brother who lived the closest to the Greeks; and finally by establishing a "more virile" culture than his brothers, whose descendants, the promiscuous and luxury-loving Agathyrsi and the sedentary and farmer Gelonians, led lives which the Greeks perceived as being less masculine and therefore derived from their Asian mother.
This Hellenised version of the Scythian genealogical myth therefore presented Skythēs as being a largely but not completely Greek figure, and, in consequence, made his Scythian descendants a people of largely Greek origin. His bow, belt, and horses which he obtained from Hēraklēs were construed in this myth as gifts thanks to which Scythian warriors obtained their offensive, defensive, and mobile capabilities, while the traits which the Greeks perceived negatively among the Scythians, Agathyrsi, and Gelonians were ascribed to their pimordial mother.
The goal of this Hellenised Scythian genealogical myth was to impose a superiority of the Greeks over the Scythians as well as to establish a dependency of the Scythians on the Greeks regarding their "civilising" arts, and finally to portray the Scythians proper, who were more Hellenised, as being superior to their more northern and non-Hellenised neighbours such as the Agathyrsi and the Gelonians.
The divine footprint
The inhabitants of the Greek colony of Tyras, who identified Targī̆tavah with Hēraklēs, believed that the footprint near the Tyras river had been left by Hēraklēs, and that this was the location where he had attained immortality and divinity. Since only gods were able to leave footprints on the hard rock, this footprint was held among the Greeks as a sign of the divinity of Hēraklēs, with such footprints being held among Greeks to represent the presence of heroes and gods at cult sites.
The large size of the footprint was also linked to the ancient Greek image of gods and heroes being recognisable by their sizes and weight, so that the two cubit-long footprint could only have been left by a powerful hero whose body size corresponded to his body size, so that the achievements of Hēraklēs were only believable if they had been carried out by a hero from ancient times whose semi-divine origin manifested itself through a physique surpassing those of regular mortals of the post-mythical age.
Greek influence
To propagate this more Hellenised version of the genealogical myth which turned the Scythians into a people of partly Greek origin, and to compete with the first version of the myth, the Greek artisans on the northern shores of the Black Sea produced artistic depictions of this story to distribute as trade goods to the Scythians.
The role of Hēraklēs in Greek religion was that of a cultural hero who advanced human settlement and society by destroying incarnations of chaos, but he was also the archetype of the human conquest of death, with Gēryōn himself, whom Hēraklēs defeated, being a representation of death; this theme was continued in the myths of Hēraklēs going to the west to being the golden apples of the Hesperides and him dragging Cerberus out of the underworld. These myths transformed the figure of Hēraklēs into an unstoppable traveller who could go to the realm of Death and return from it.
Therefore, the Scythian rulers saw the Greek myth of their people as descendants from Hēraklēs as an attractive one, not unlike the similar beliefs held by the kings of Sparta and Macedonia. This is attested historically when the Macedonian king Philip II requested the permission of the later Scythian king Ateas to erect a statue to Hēraklēs at the mouth of the Danube, which shows that both the Macedonian and Scythian kings commonly respected Hēraklēs.
The Herodotean narrative
When Herodotus of Halicarnassus recorded the Hellenised version of the genealogical myth, he exhibited scepticism towards this narrative within his own text largely because he doubted that the Ocean encircled the earth, but also partly because he had close connections with the Western Greeks of Magna Graecia, who believed that Hēraklēs had driven the cattle of Gēryōn through their region of the world, and therefore did not accept that he had made a detour to the north to Scythia. Thus, Herodotus clarified that this was a myth told to him by the Pontic Greeks as a clarification to his Western Greek audience who would likely have been hostile to this myth.
Herodotus of Halicarnassus described this footprint as being the only wonder in Scythia. Its location, near the river Tyras, also had a symbolic value in the works of Herodotus, since in his worldview rivers separated not only great empires, but also the real world from the mythical world, so that anyone crossing them risked entering a strange world and could be punished through blindness. The status of Scythia as being uninhabited when Hēraklēs arrived there was itself described as a liminal area between the mythical and fantastical worlds in the narrative of Herodotus; the stormy and frosty climate of Scythia, which Herodotus typically used to describe distant lands inhabited by fantastical peoples and creatures, was also such an indication of Hēraklēs entering into a liminal region.
Since Herodotus perceived the Scythians and the Egyptians as being diametrical opposites, the footprint of Hēraklēs in Scythia was also the counterpart to the two cubit-long sandal of Perseus at Khemmis in Egypt: both marked places which had been sacralised by the appearance of heroes and where the divine and human realms overlapped; at the same time, while Hēraklēs had left his permanent footprint in Scythia, Perseus instead had a fleeting presence, so that the presence of his sandal in his sanctuary in Khemmis was a sign of his visit.
The Herodotean record of the Scythian genealogical myth was also intended to present to his audience another group of enemies whom the Greeks' Persian enemies had faced in the form of the Scythians and to create a common picture of the Greeks and Scythians who were both invaded by the Persians as a punishment for previous wrongdoing. This narrative itself was placed by Herodotus in the framework of the "primordial struggle" between Asia and Europe which was the Trojan War. Therefore, the narrative of Herodotus crafted a Greek ancestry for the Scythian "comrades" of the Greeks in their struggle against the Persians.
The various Herodotean presentations of the origin of the Scythians, including both versions of the genealogical myth as well as the "Polar Cycle," were intended to present the nomadic lifestyle that enabled the Scythians to defeat the Persians as resulting from an environmental disaster in the form of a northern cold which forced them to resort to a life of wandering and to therefore be recent arrivants in the Pontic Steppe.
The narrative of Hēraklēs wandering through the unfamiliar country of Scythia to search for his horse was itself recorded by Herodutus as a parallel to how the Persian army became lost and exhausted its forces while trying to pursue the Scythians during the Achaemenid invasion of Scythia in 513 BCE. At the same time, the Scythians, who were presented as descendants of Hēraklēs in this story, in consequence were protected by him through his divine power to ward off evil, which was also attested through his epithet of ().
Similarly, Hēraklēs reaching the abode of the Snake-Legged Goddess in the Woodland of Scythia after she abducted his horses in the myth paralleled how the Scythians intentionally drawing the Persians deeper into Scythia by laying deceptive trails.
Ritual
Relics
The peoples of Scythia believed that Targī̆tavah had left his footprint in the territory of the Tyragetae, in the region of the middle Tyras river, which the local peoples of this area displayed proudly. The location of this footprint was itself held to have a religious signification, since the Tyras river formed the western limit of the Eurasian steppe and its western banks were elevated, due to which the god of that river was worshipped in Scythia.
The inhabitants of the Greek colony of Tyras appear to also have had their own variation of the myth of Hēraklēs passing near their city, which is suggested by the presence of the image of Hēraklēs and bulls representing the cattle of Gēryōn on this city's coins.
Shrines
At Hylaea
A Greek language inscription from the later 6th century BC recorded the existence of a shrine at Hylaea which was held in common by both Scythians and Greeks. The shrine at Hylaea was the location of altars to:
the god of the Borysthenes;
Targī̆tavah, referred to in the inscription as Hēraklēs;
the Snake-Legged Goddess, referred to in the inscription as the "Mother of the Gods," because the Greeks identified her with their Mother Goddess Cybele due to her chthonic nature.
The inscription located this shrine in the wooded region of Hylaea, where, according to the Scythian genealogical myth, was located the residence of the Snake-Legged Goddess, and where she and Targī̆tavah became the ancestors of the Scythians; the deities to whom the altars of the shrine were dedicated to were all present in the Scythian genealogical myth. The altars at the shrine of Hylaea were located in open air, and were not placed within any larger structure or building.
The Olbiopolitan Greeks also worshipped Achilles in his form identified with Targī̆tavah at Hylaea.
Women performed rituals at the shrine of Hylaea, and the Scythian prince Anacharsis was killed by his brother, the king Saulius, for having offered sacrifices to the Snake-Legged Goddess at the shrine of Hylaea.
Thus, the Olbia-centricity of the Hellenised variant of the genealogical myth also constituted an origin myth for the cult of Targī̆tavah-Hēraklēs at Hylaea, and the mention of the horses of "Hēraklēs" being stolen by the Snake-Legged Goddess dwelling at Hylaea explained the presence of horses in the rituals of this cult.
At Tyras
A cult centre might have existed at the site of the footprint of Targī̆tavah-Hēraklēs on the Tyras river.
The ritual sleep
The ritual sleep was a ceremony conducted at the Holy Ways, where the great bronze cauldron representing the centre of the world was located. During this ceremony, a substitute ritual king would ceremonially sleep in an open air field along with the gold for a single night, possibly as a symbolical ritual impregnation of the earth. This substitute king would receive as much land as he could ride around in one day: this land belonged to the real king and was given to the substitute king to complete his symbolic identification with the real king, following which he would be allowed to live for one year until he would be sacrificed when the time for the next ritual sleep festival would arrive and a successor of the ritual king was chosen. This ceremony also represented the death and rebirth of the Scythian king.
This festival corresponded to the royal consecration ceremony of the Indic peoples, where the borders of the king's realm were determined by the territory around which his horse walked.
During the ritual sleep ceremony, the king of the Royal Scythians performed the duties of a priest, thus acting as a priest-king.
The ceremony of the ritual sleep was the main event of the Scythian calendar, during which the Scythian kings would worship the gold with rich sacrifices. The ceremony might have been held at the moment of the Scythian calendar corresponding to the fall of the gold objects from the heavens.
In art
The Scythian genealogical myth was often featured in Scythian art.
The struggle against chaos
A Scythian depiction of the combat of Targī̆tavah against the chthonic personification of chaos might have been present on one of the bone plaques decorating a comb from the , which was decorated with the scene of two Scythians fighting a monster with the front-legs of a lion, a scaly body, and a fish- or dragon-like split tail, with the monster's appearance connecting it to the element of water, and therefore to the chthonic realm; one of the Scythians in the scene is depicted as dying in the monster's leonine paws while the second man kills it with a spear.
The trial of the sons
The narrative where the three sons of Targī̆tavah were tasked to string the bow of their father might have been represented on a silver cup from Voronezh whose surface is decorated with three scenes where Targī̆tavah explains his first son the task, then banishes his second son for failing the task, and finally gives the younger son a bow as reward for fulfilling the task.
Unlike the Greek retelling of the myth, in which "Hēraklēs" returns to Greece and instructs the Snake-Legged Goddess to put their three sons through the trial of the bowstring, these scenes instead represent, in accordance with Scythian traditions of patrilineality, the divine paternal ancestor of the first king, that is Targī̆tavah himself, putting his sons through the trial.
Another representation of the trial of the sons of Targī̆tavah might have decorated an electrum vessel from the Kul-Oba kurgan, where Targī̆tavah is represented wearing a Greek-type , and his two elder sons who had failed the task of the bowstring are depicted being healed while the third son is shown stringing the bow.
Scythian coins
Coins of the Scythian king Eminakes struck at Pontic Olbia were decorated on their reverse with images of Targī̆tavah, who was Scythian kings' personal symbol, and who was depicted on the coins as the Greek Hēraklēs wearing his lion-skin, and stringing a bow while his knee is bent. Unlike other Greek coins in which Hēraklēs is depicted as an archer, his posture in the coins of Eminakes is similar to that of Targī̆tavah's son stringing the bow from the Kul-Oba vessel.
Coins of the later Scythian king Ateas were struck with the image of the head of Hēraklēs wearing a lion-shaped helmet. These coins primarily copied Macedonian ones, and were meant to signal the Scythian kingdom as being an equal of the Macedonian kingdom of Philip II, although the choice of the head of Hēraklēs was also meant to emphasise Ateas's descent from Hēraklēs, who was assimilated to Targī̆tavah.
Comparative mythology
Indo-Iranic parallels
Other Iranic parallels
Several parallels to the Scythian genealogical myth existed in various Iranic traditions.
Zoroastrian parallels
Social classes and Zoroastrian kingship
In the , the three sons of Zarathustra are assigned the roles of the progenitors of the three social classes, with the eldest son being the head priest, the second son being an agriculturist, and the third son being a warrior.
In another passage of the where Zarathustra appears in relation to the three social classes, Zarathustra bestows upon Vištāspa the blessing that he would have ten sons, of whom three would be priests, three would be warriors, and three would be farmer-agriculturists, and one who would be like Vištāspa himself.
The concept of the king encompassing and transcending the social classes is present in the Zoroastrian tradition, with the and the of the explicitly propounding this notion of kingship, which was reiterated by the 9th century AD Zoroastrian scholar Zādspram in his writings.
The blessing bestowed by Zarathustra to Vištāspa, according to which Vištāspa would have ten sons, of whom three would be priests, three would be warriors, three would be farmers, and the tenth would be like Vištāspa, was derived from the Iranic notion of the three sons as the progenitor of the three social classes, while the tenth son who was to be like Vištāspa represented the king within whom the functions of these three social classes were united.
Paralleled the role of the belt with a cup attached to it in establishing Skythēs's role as the supreme priest, Zarathustra was believed to have first established the practise wearing of the belt which adherents of Zoroastrianism had to start wearing from a young age.
Haošiiaŋha and his heirs
The name was a Greek reflection of the Scythian name , which was a cognate of the Avestan title (), which means "first created." In the , Haošiiaŋha was the first king and the ancestor of the warrior class, that is of the military aristocracy of which the kings were members, and the title was assigned in Zoroastrian literature to the first king, Haošiiaŋha, and to his descendants and successors, the Pishdadian dynasty.
In Avestan mythology, Haošiiaŋha Paraδāta held the role of the warrior-king who fought against non-Iranic "barbarians" and had both human and demonic enemies, and also laid the foundations of royal power and of sovereignty.
Haošiiaŋha's son Taxma Urupi, who also bore the title of , meanwhile corresponded to the priest-king, being opposed to the same enemies of Haošiiaŋha as well as to sorcerers, and he managed to use magic to turn Aŋra Mainiiu into his horse which he rode for thirty years. Taxma Urupi in Avestan mythology also curbed idolatry and promoted the worship of Ahura Mazdā, and was also credited with inventing writing, which were all attributes of a priest-king, thus making him the equivalent of Lipoxšaya.
Taxma Urupi's successor to the kingship, Yima, meanwhile held the role of a "prosperous king," which corresponded to R̥buxšaya's role as the progenitor of the farmer class. Taxma Urupi's creation of the underground enclosure, the , connected him to the lower world, which also signalled his association with the role of the progenitor of the farmer class. Yima's epithet of (), meaning "brilliant" and "shining" was a sign of his proximity to the Sun and the Moon due to his possession of the in his capacity of being king.
A myth similar to that of the golden objects falling from the sky was also present in the , where Ahura Mazdā offered to Yima a (either a pick or a shepherd's flute) and an (a cattle goad), both made of gold, which Yima used on the earth to increase the size of its part which was inhabitable.
The role of R̥buxšaya as the progenitor of the farmer class finds another parallel in the Zoroastrian tradition, where Haošiiaŋha's brother Vaēgerēδ was the creator of agriculture and the ancestor of the farmer class.
Θrita
In the of the , the hero Θrita was the third mortal man to have prepared the sacred drink. Θrita in turn had two sons, of whom Urvāxšaya was a religious mentor as well as a judge and a lawgiver, while Kərəsāspa was a famous heroic warrior who slew a horned dragon.
The
The and kingship
Ahura Mazdā offered to Yima the and which Yima used on the earth to increase the inhabitable part of the Earth in the , and Yima used his to perform this task the , thus identifying the with the and . This story paralleled the acquisition of the of Tāpayantī by Kolaxšaya, who thus became the possessor of the and of its physical symbols.
The was believed to follow the legitimate king and escape from usurpers, but it was also believed to leave the legitimate king and pass over to a better candidate should he become unjust and violate the laws. Thus, in the , when Yima started to believe lies, his left him three times in three parts: one part took on the form of the Vārᵊγna bird to pass onto the god Mithra, one part passed onto the prince Θraētaona, who became king, and the third part passed onto Θrita's son, the hero Kərəsāspa, who became a dragon-slaying hero just as Θraētaona had previously been, as a result of which Yima lost the kingship and was succeeded by Θraētaona.
The narrative of the leaving the legitimate king after corruption is present in the , where the king Kāy Us lost his after attempting to conquer the heavens.
In the , Nōtargā attempted to steal the of Frētōn by using witchcraft to place it inside a cow whose milk he gave to his three sons to drink. The rejected each of the sons, and instead passed into one of Nōtargā's daughters, who later gave birth to Kay Apīveh, who possessed the from birth and became the second Kayanian king and the true founder of the Kayanian dynasty, after which his passed on to his heirs. Although this myth is not directly connected to the Scythian genealogical myth, this narrative of the choosing its possessor is nevertheless similar to how the of Tāpayantī rejected Lipoxšaya and R̥buxšaya, and instead chose Kolaxšaya to become their possessor.
The and the social classes
Like among the Scythians, the in Zoroastrianism was also tripartite, which is reflected in a myth recorded by Zādspram, according to which humans at the time of Hōšang (Haošiiaŋha) - although the sets the story during the time of Taxmurup (Taxma Urupi) - were able to travel from one region of the earth to another on the back of the gigantic bull Srisōk. However, the sacred fire on the back of Srisōk fell into the sea and separated into three Zoroastrian Sacred Fires which possessed the and were established at three sites. These Three Fires were:
Ādur Farnbāg, which was dedicated to the priestly class;
Ādur Gušnasp, which was dedicated to the warrior class;
Ādur Burzēn-Mihr, which was dedicated to the farmer class.
Unlike the Scythian , the three components of the of the Sasanian period were kept separately due to a later Zoroastrian eschatological notion recorded in the , according to which the union of the Fire of the Priests and the Fire of the Warriors was capable of destroying evil, preserve creation, and the renewal of existence. Therefore, since evil still existed in the world, the reunification had to happen in the end times.
Although the Three Fires were located in physically separate spots, they were nevertheless all present within the same kingdom ruled by the same king, due to which the Sasanian kings possessed all three components of the .
Although Yima is depicted in later Zoroastrian literature as possessing only two physical manifestations of the , the and , in the , he used three fires to perform all his tasks during his reign, with these fires corresponding to the royal and to the three Scythian possessed by Kolaxšaya. The reference to the "three fires" suggests that in the earlier variants of the myth, Yima was a perfect king who owned an object representing the priestly function in addition to the and , thus possessing the sacred objects which represented the three aspects of kingship and the three social classes, thus corresponding exactly to the three objects which were in the possession of Kolaxšaya in the Scythian genealogical myth.
The discrepancy between Yima possessing three sacred objects in the earlier form of the myth and only two in the later variant is due to a later Zoroastrian development, recorded in the narrative from the , where Ahura Mazdā initially offered to Yima to study and preserve the Good Religion, which Yima refused. Ahura Mazdā then offered kingship of the whole world to Yima, and he accepted and therefore received the and , which are described in the text of the as the , meaning "royal powers," and which respectively represent the farmer and warrior functions. Since Yima refused to preserve religion, he did not possess the third physical manifestation of the representing the priestly class, which was to be owned by Zarathustra, hence why the objects possessed by Yima became reduced to two in later Zoroastrian myth.
These differences resulted from innovations by the priestly class to discredit the claims of the kings of being the divine agents, and which were canonised in the myth of Yima believing the lies. According to this myth, Yima performed faultless sacrifices which ensured that paradical conditions on prevailed on Earth during his thousand-year rule which were marked by perfect climate, the unity of all beings under his rule, the powerlessness of demons, and the absence of death, old age, hunger, and thirst. However, Yima then listened to the lies and claimed that he was the one who had created all the spiritual and material beings, after which he lost divine favour and his left him, and his perfection and Golden Age ended and were replaced by the present human world where death, disease, wars, demons, lying kings, and propaganda prevailed. This state of trouble could only be ended by the establishment of the Good Religion, which was founded by Zarathustra, who founded priestly institutions, teachings, practices, and texts; unlike othe ancient Iranic traditions which held that the king was the divinely-ordained agent who had to restore the primordial paradise, in the Zoroastrian tradition, kings caused disasters for themselves as well as their people and the world because they would inevitably lie, thus making kings themselves the responsibles for the end of this paradisal state.
Therefore, Yima's kingship in later Zoroastrian literature was incomplete, since he united within himself the warrior and farmer functions, but not the priestly one, hence why Yima is described in Zoroastrian literature as possessing the full royal but none of the religious , while Zarathustra possessed the full religious but none of the royal .
However, in some myths relating to Yima, he possessed a belt, which was a symbol of the priestly class, and Yima's belt was even said to be identical to the Zoroastrian religion in some texts, thus allowing him to use the belt to render Ahriman (the Avestan Aŋra Mainiiu) and his demons powerless. This paralleled the role of the belt with a cup attached to it in establishing Skythēs's role as the supreme priest.
According to the , Yima's passed on to:
Frētōn (the Avestan Θraētaona), who received the farmers' part of the ;
Sāmān Karsāsp (the Avestan Kərəsāspa), who received the warriors' part of the ;
Ošnar, a sage who received the priests' part of the .
In the of the , Ahura Mazdā told Zarathustra that whoever would be able to capture the that once belonged to Yima, which was hidden in the Vourukaša ocean, would obtain three boons, consisting of the boon of the priests, the boon of well-being and wealth, and the boon of victory with which he would be able to destroy all enemies. These three parts were reunited in the of the kings of the Kayanian dynasty.
In both the 's and the 's narratives, the three parts of Yima's are listed in the same order as the sons of Targī̆tavah, with the first part corresponding to the priests, the second part to the farmers, and the third part to the warriors.
The
In the Zoroastrian eschatological text, the , the hero Ferēdūn had three sons, who each represented the social classes, were also the ancestors of the three major populations of the known world:
the eldest, Salm, was the ancestor of the producer class, and became the ruler of Rome;
the second, Tōz, was the ancestor of the warrior-aristocracy, and became the ruler of Turkestan and the desert;
the third, Ēriz, was the ancestor of the priesthood, and became the ruler of Iran and India.
This variant of the myth had, however, undergone some modifications proper to Zoroastrianism, so that the dominant class descended from the youngest son of Ferēdūn was that of the priests rather than the warrior aristocracy. Some aspects of the original version of the myth were nevertheless still present, so that Ferēdūn still gave to Ēriz the , which was normally an attribute of the kings and of the warrior aristocracy; and the power of Ēriz it itself described in the as consisting of , that is of royalty and rulership. In the , Ēriz instead received from his father the (), that is speech, due to the replacement of the original royal attributes of Ēriz by priestly ones.
The roles of the sons of Ferēdūn as the ancestors of three peoples parallel the second version of the Scythian genealogical myth recorded by Herodotus of Halicarnassus, where the sons of "Hēraklēs" each became the ancestors of a Scythic tribe.
The sons of Mihr-Narseh
In the 5th century AD, the Sasanid Mihr-Narseh had his three sons appointed to important positions at the head of the three estates of Persian society:
the eldest son was named the , which was the second highest position within the clerical hierarchy;
the second son was appointed as the , that is the head of the agriculturists, who was also the minister in charge of taxation and finance;
the third son became the , that is the head of the warriors, and the grand marshal.
The order of the respective professions of the sons of Mihr-Narseh corresponded to the functions of the sons of both Zarathustra and Targī̆tavah, and Mihr-Narseh might have intentionally chosen this order of professions to emulate Zoroaster himself or one of the ancient pious kings of Zoroastrian mythology.
Mihr-Narseh also built four fire temples near his home town, with one being for himself and corresponding to the king's personal fire, which was also the prime fire of the empire, and the other three corresponding to each of his sons and which also corresponded to the three Great Fires of the Sasanid Empire.
The primordial unity
The theme of the primordial unity of creation was also present in the Zoroastrian cosmogenetic myth, where Ahura Mazdā created the Sky, Water, Earth, Plant, Animal, and Human. The first Plant, Animal, and Human each included within their bodies all of the good qualities which were present in the various plants, animals, and humans who later came into existence, so that this state of primordial perfection was characterised by integrity of body and spirit, due to which these original beings were free of vice, disease, suffering and death.
This primordial perfection was lost when Aŋra Mainiiu attacked the creations of Ahura Mazdā and killed the primordial plant, the primordial animal, and the primordial human in this specific order. However, the death of these primordial beings was not their end, and they instead fragmented into smaller parts which then became the many types of plants, animals, and humans, all of which contained both some good and some evil, and the ability to reproduce, which was itself the replacement of immortality by the perpetuation of the species. Thus, the original perfection was replaced by a combination of good and evil, and the shattered primordial unity became a multiplicity, with these changes creating the possibility for the arising of confusion and conflict.
Therefore, Ahura Mazdā expected that one day Aŋra Mainiiu would be vanquished, and the primordial perfection would be restored, which can only be accomplished by the suppression of liars, evil-doers, and all destructive forces. To achieve this, the Zoroastrian tradition made Zarathustra the one chosen by Ahura Mazdā to help righteous humans fight Aŋra Mainiiu by cultivating good thoughts, good words, and good deeds, the latter of which included ritual as well as ethical action. Therefore, Zoroastrianism considers unity and harmony as achievable by performing sacrifice, purification, and recitation of sacred hymns, due to which it places priests as the ones in charge of restoring the primordial perfection.
Thus, the goal of the priests in the Zoroastrian religion was to restore the primordial paradise which existed at the beginning of creation.
This theme is repeated in the myth of Yima, where the paradisal state of the world characterised by abundance, contentment, immortality and perfect peace under his rule corresponds to the primordial unity and perfection. However, once Yima believed the lie, the primordial unity underwent fragmentation, starting when he lost his , which split into three, after which Yima himself was eventually killed by demons and his body was dismembered, and the paradisal Golden Age ended and was replaced by a state of multiplicity, mixture of good and evil, and trouble in the form of the present world dominated by death, disease, wars, demons, and lying kings.
According to the Zoroastrian religion, the solution to these troubles was the establishment of the Good Religion by the divinely-ordained Zarathustra, who in consequence founded priestly institutions, teachings, practices, and texts.
Persian parallels
The primordial unity
The theme of the promordial unity was also present among the religion of the ancient Persians, and was often mentioned in Achaemenid royal inscriptions, in which the kings held Ahura Mazda as the source of all creation who brought Heaven, Earth, humanity, and happiness into existence. In these inscriptions, Heaven, Earth, humanity and happiness were all referred to in the singular to denote the state of primordial harmony and unity which initially existed, and during which humanity lived in absolute bliss characterised by peace, calm, and freedom from all conflict.
This primordial perfection was lost when the Lie entered existence and shattered unity, and spread. Finally, according to the Achaemenid inscriptions, this crisis was resolved when Ahura Mazda made Darius I king in an act of divine creation. Within this scheme, Darius presented himself as representing the institution of ideal kingship who led the divinely-orgained struggle ensure that good prevails over evil, truth prevails over falsehood, and unity prevails over multiplicity, hence why Darius's inscriptions ended by naming him as "one king over many, one commander over many" ().
In one of Darius's inscriptions from Susa, this cosmogenetic narrative is repeated, with Ahura Mazda being described as creating a "wonder," which is also the term used to refer to the palace that Darius had built in Susa: multiple other inscriptions from Susa describe Darius as having the most skilled artisans from all of the Achaemenid Empire's provinces work the most precious materials of their respective homelands to build the palace, which itself represented a microcosmic wonder which grandiosely restored the perfect unity of creation. In Darius's Susa inscription, his actions are referred to in such a way that he parallels Ahura Mazda, thus portraying Darius as the Creator God himself, rather than as a figure of salvation created by the Creator God.
Therefore, within the Achaemenid Persian religion, like in Zoroastrianism, the primordial perfection had to be restored through the suppression of liars, evil-doers, and all destructive forces. However, in the Achaemenid tradition, it was the king who was the agent chosen by Ahura Mazda to restore the primordial perfection by defeating rebels and enemies, proclaiming the truth, imposing the law, uniting all peoples under his rule, and building palaces and gardens where perfect happiness would re-emerge and radiate through creation.
Thus, the goal of the kings in the Achaemenid religion was to restore the primordial paradise which existed at the beginning of creation.
The three brothers
The myth of an ancient and pious king whose three sons were the progenitors of the three social classes appears to have existed among the Persians up till the Sasanian period in the 5th century AD.
The king and the social classes
The Achaemenid kings would wear the peasant clothes of their empire's founder, Cyrus II, and eat a peasant's meal before being consecrated by the priests, being a ritual whereby the king, who originated among the warrior-aristocracy, also became a member of the producer class. This suggests that the Indo-Iranic concept of the king originating among the warrior-aristocracy and then ritually becoming a member of the priestly and farmer classes, thus encompassing the three social functions and representing all the classes by being himself the incarnation of society.
In a prayer from Persepolis, the Achaemenid king Darius I asked Ahura Mazda to protect his kingdom from ills relating to the three social functions, and consisting of hostile armies (representing the warrior function), bad harvests (representing the producer function), and lies (representing the religious aspect). The king thus protected his realm from these three evils because he was himself held to be the good warrior, the protector of the land and of the peasants, and the just king, which were often mentioned virtues in Achaemenid royal inscriptions.
The Achaemenid king Xerxes I performed a sacrifice to the Sun-god on the shores of the Hellespont where, after having poured a libation, he threw in the sea a cup representing the priestly class, the golden which might have represented the farmer class, and an which represented the warrior class. Alternatively, the cup and the might both have represented the priestly class while the still represented the warrior classes, which parallels the second version of the Scythian genealogical myth whereby only the priests and the warriors were represented by objects.
The last Achaemenid king, Darius III, wore a ceremonial dress which was decorated with gold and precious stones, and whose colours were white for the priestly class, purple for the warrior class (the gold and the precious stones also represented this class), and dark blue or green for the farmer class. The colour schema of this ceremonial dress represented the unification of the three social classes within the figure of the king.
The golden objects of the Scythian genealogical myth, that is the of Tāpayantī, as attested by their fiery nature, were the fires of the three classes of Scythian society, which had an equivalent in later Sasanid Persia, where the Three Sacred Great Fires of Zoroastrianism were considered as each being sacred to one social class, with the triunity of both the Scythian and the Sasanian Great Fires representing the concept of fire, represented in the Scythian religion by Tāpayantī, being the primeval and all-encompassing element permeating the world and being present throughout it.
During the Sasanid period, the mythical , a composite creature whose anatomy consists of parts of a bird, a dog, and a fish, had been used as a symbol of royalty because the constituent parts of its body meant that it united within itself the three social classes which correspond to the three - celestial, earthly, chthonic - layers of the world in Iranic cosmology, similarly to how the Iranic kings encompassed within themselves and represented these three classes.
The
The notion of the transforming the king into a divine figure and a type of deity who was sometimes seen as the brother of the Sun and the Moon was also present among the pre-Islamic Persians. Instances of this concept include Herodotus's claim that Darius I was chosen to be king when his horse was the first to neigh at sunrise, and the 's record that Pābag's first dream, in which the Sun shining from the head of Sāsān and illuminating the whole world, was a sign that Ardašīr I would become king. Various Persian kings also held solar titles, and, like the Massagetae, the Persians also sacrificed horses to the Sun-god, with such sacrifices having been performed monthly at the tomb of Cyrus II, signalling that he had been assimilated to the Sun.
Due to the Iranic belief of gold being a material representation of , Achaemenid kings kept large numbers of gold objects in their palaces which would help them preserve their .
Because the was believed to be dangerous due to its solar nature, accidentally seeing the king's was considered capable of blinding or even killing whoever accidentally saw it. The Persian practice of , whereby all who met the Achaemenid king had to prostrate before him and had to wait for his permission to rise up again, might have developed as a way to prevent ordinary humans from losing their eyesight or lives by accidentally seeing the royal .
As a result of the perceived dangerous nature of the royal , Achaemenid kings were not supposed to come in direct contact with ordinary people. Therefore, as among the Scythians, all interactions between members of the ordinary population and the king had to be made through special intermediates appointed by the king himself.
During the Sasanian Empire, those who obtained audiences with the king had to cover their mouths with a white cloth called a (), which was also worn by Zoroastrian priests, in both cases with the aim of preventing the human breath from polluting the sacred fire, which in the temples were the physical fires burning in them, and for the king was his . The king's (called was thus assimilated with the burning fire.
According to the , in Pābag's third dream, he saw the Three Sacred Fires, that is Ādur Farnbāg, Ādur Gušnasp, and Ādur Burzēn-Mihr, burning inside the house of Sāsān and illuminating the whole world, which was a sign that a descendant of Sāsān would acquire kingship. This dream also represented the king as the ruler of the three social classes, due to which their corresponding Three Fires which constituted the in Middle Persian) belonged to him. The among Persians thus was also tripartite.
The text of the presented Ardašīr I as being the legitimate king through his possession of the Three Sacred Fires, and Ardašīr I he had a fourth sacred fire, called the Fire, consecrated during his coronation. This was a royal fire which represented the reign of Ardašīr I and was extinguished at his death, after which a new royal fire was consecrated by each Sasanian king. This royal fire represented the unity of the royal and the union of the three social classes within the king.
This concept was later recorded by Zādspram, according to whom Fire was the abode of the royal . This view is also present in , according to which the Three Sacred Fires represented the one body of the Fire and were contained in it. The Fire thus encompassed the Three Fires of the three social classes and was the incarnation of the royal , while the Three Fires were the incarnations of its constituent parts.
In a legend recorded by al-Bīrūnī, the Sasanian king Peroz I went to perform devotions in one of the most important Fire Temples, named Ādur-Xwarrah, where he embraced with his arms the fire of the temple in the same way that friends did when greeting each other, and the fire reached his beard but did not burn him. According to this legend, the king not burnt because he was himself as an emanation of the sacred fire.
The Persian imperial banner, known in Modern Persian as the (, meaning "standard of the kings"), had been used from Achaemenid times till the end of the Sasanian empire as the physical representation of the kings' . The identification of the with the is confirmed in the , where the / was identified with the gods' standard borne by Vərᵊθraγna. The Persians believed that the initially belonged to Θraētaona/Ferēdūn, who bore it during his struggle against Dahāg, and that Ferēdūn emerged victorious thanks to the banner, after which it was inherited successively by his descendants, the Persian kings, who believed that it would ensure their victory in war.
The
The legend of the three sons of was also preserved in the , although its social aspect is less obvious, but not fully lost either.
The Scythian genealogical myth's narrative of Kolaxšaya dividing his kingdom among his three sons, who in turn became the ancestors of the different Scythic tribes exhibits clear textual and narrative parallels in the Persian , with the story of the descendant of Hōšang (Haošiiaŋha), Ferēdūn, and the latter's three sons – Salm, Tūr, and Īraj – from the .
The narrative of the murder of Kolaxšaya by his elder brothers fits the common motif of the competition between three brothers in which the youngest is victorious and is then murdered by his elder brothers. This motif is also present in the , where Ferēdūn tested his three sons, with the youngest, Īraj winning the test, after which Ferēdūn partitioned his kingdom among his sons and giving the best part to Īraj, who was then murdered by his jealous elder brothers.Another story from the with which the Scythian genealogical myth exhibits textual and narrative parallels is that of Īraj's descendant, Rostam, who went looking for his horses which he had lost during his sleep. When looking for his, Rostam arrived at the palace of the king of Samangan, and in the night he was visited by the king's daughter, Tahmīna, who had stolen his horses, and who asked him in marriage. Rostam accepted Tahmīna's proposal and had a son with her, but Rostam had to leave Tahmīna after the marriage ceremony, although before departing he gave her a jewel from his bow as a symbol of future child.
The parallels between this Persian myth and the second version of the Scythian genealogical myth recorded by Herodotus of Halicarnassus thus attest that the latter myth was of a typically Iranic origin, or alternatively that the 's author, Ferdowsī, had read the second version of the Scythian genealogical myth as recorded by Herodotus.
In the , the Sasanian king Ardašīr I's (), that is his /, transformed itself into a , whose composite nature consisting of parts of a bird, a dog, and a fish, meant that it united within itself the three social classes which correspond to the three - celestial, earthly, chthonic - layers of the world in Iranic cosmology, similarly to how the Iranic kings encompassed within themselves and represented these three classes.
The Sword of Mars
According to Jordanes, the Hunnish king Attila from the Migration Period claimed to have obtained the sacred Scythian sword which had fallen from the sky that he called the "Sword of Mars," and which he believed made him powerful in war and made of him the "prince of the entire world." This was a later continuation of the Scythian tradition of the golden objects which had fallen from the heavens.
Ossetian parallels
In Ossetian folklore, the ancestor of the Ossetian people, Os-Bæǧatyr (), had three sons, respectively named Sidæmon (), Kusæg (), and Æǧwyz (), who each founded a clan. Each of the clans possessed certain attributes, and each of their ancestors among the three sons of Os-Bæǧatyr received an object made of gold corresponding to these attributes:
Sidæmon received a golden cloth, and his descendants were numerous in number;
Æǧwyz received a sword, and his descendants were valorous warriors;
Kusæg received a ball, and his descendants were renowned.
The myth of the sons of Os-Bæǧatyr therefore corresponded to the first variant of the Scythian genealogical myth, with the three sons who founded the three social classes and functions each receiving sacred objects made of gold which represented these functions. Unlike in the Scythian myth, however, each brother became the possessor of one of the three objects, reflecting the more egalitarian social norms of the Sarmatian ancestors of the Ossetians.
In the
The Scythian religion's three-fold division of the universe into three levels and society into three classes is present in the Ossetian , where the three clans of the Nartæ lived in three different neighbourhoods or villages of the same mountain:
the Æxsærtæggatæ () clan represented the warrior class and lived on the higher level of the mountain;
The ancestor of the Æxsærtæggatæ, Wærxæg, was a figure who exhibits similarities to Kolaxšaya.
the Alægatæ () clan represented the priestly class and lived on the middle level of the mountain;
the Borætæ () clan represented the farmer class and lived on the lower level of the mountain.
The different clans corresponded the different social classes, and the levels were they respectively lived represented their respective classes' position within the three-fold class structure of the Scytho-Sarmatian peoples. The location of the Æxsærtæggatæ at the highest level of the mountain was thus a representation of the dominance of the warrior aristocracy over the priestly and farmer classes.
A similar narrative to the myth of the struggle between the Paloi and the Napoi is present in the , where the clan of the Æxsærtæggatæ, who possess manhood and strength and therefore correspond to the -, exterminate the clan Borætæ, who were wealthy and therefore corresponded to the Katiaroi and Traspies. Only the warrior and producer classes are mentioned in this myth because the priestly class was completely subordinate to the warrior aristocracy.
In the , the hero Batyraʒ was born from the union of the hero Xæmyts and an unnamed nymph who was the daughter of the river-god Donbettyr, similarly to how the ancestor of the Scythians was born from the union of Targī̆tavah and the Snake-Legged Goddess in the Scythian genealogical myth.
Batyraʒ later had to go through three trials which represented the three social functions to prove himself as the best among the Nartæ: he had to prove himself as a heroic warrior in the first trial; conduct himself decently at feasts held during festivals in the second trial; and conducting himself nobly towards women.
As reward for succeeding in his trial, Batyraʒ received three ancestral treasures, which corresponded to the narrative of Kolaxšaya successfully passing the test to obtain the three golden objects in the first version of the Scythian genealogical myth, but also to the second version of the genealogical myth where Skythēs had to go through two different trials which each corresponded to one social function.
Batyraʒ thus corresponded to the Iranic concept of the ideal king whose rule is guaranteed by his possession of the physical representations of the three social classes and who embodies their three domains of activity; however, since kingship had ceased to exist among Ossetians, Batyraʒ therefore became the best among the Nartæ instead of the king.
The equivalent of the horse of Kolaxšaya in the might have been the celestial horse Ærfæn, who is often referred to as being winged and fiery-footed in the sagas. Ærfæn was the horse of Wastyrǵi, who was the patron saint of men and warriors, or of Wyryzmæg, the eldest member of the Æxsærtæggatæ who was also similar in certain ways to Kolaxšaya.
Within the , the closest parallel to Kolaxšaya was Soslan, and the three celestial boons of the Nartæ were called the treasures of Soslan. Among other presents from the gods, Soslan had received the horse Ærfæn, who was invulnerable just like Soslan and could be killed only by stabbing its hooves. Ærfæn later avenged Soslan by killing the responsible for his death, Syrdon.
Ærfæn itself was the ancestor of a group of miraculous horses named the Dur-dur, meaning "horses of stone," and who bore the epithet of (, from Old Iranic , meaning "strong horse," and also present in the Sarmatian anthroponym () and ethnonym ()). According to the , each of the clans of the Nartæ was connected to a clan of horses, and themselves might have belonged to the Æxsærtæggatæ, who corresponded to Kolaxšaya and the Paralāta.
The horse of Wyryzmæg and Soslan had a white coat, which connected it to the priestly function, while the horse of Wastyrǵi had a white or red coat, with the red colour being that of the warrior function: this colour combination thus represented the fusion of the priestly and warrior functions and the prominence of the warrior-aristocracy among the Scythian peoples.
Indic parallels
The meaning of the name of Lipoxšaya as possibly meaning "king of heaven" connected him to sun-deities or to gods of the heavens such as Dyauṣpitṛ and Iūpiter.
The name of R̥buxšaya was formed following the same structure as the Sanskrit theonym (), who was the leader of Ṛbhú and formed a triad with the other two members of the Ṛbhú. Likewise, R̥buxšaya formed a triad with the Katiaroi and the Traspies, with the name of the Traspies, which was semantically connected to the name of one the Ṛbhu, Vibhu, whose name meant "mighty" and "prosperous."
The name of the father of the Ṛbhu, Sudhanvan, meant "having a good bow," which made him an equivalent of Targī̆tavah, the possession of whose bow was necessary for his sons to obtain royal power.
Kingship
The narrative of the Kolaxšaya successfully passing the tests to become king in both versions of the genealogical myth also found a parallel in the Indic myth of the king Pṛthu as retold by Megasthenes, who identified him with the Greek god Dionysos and the Greek hero Hēraklēs. According to Megasthenes's narrative, when "Dionysos" first arrived in India, he found that there was no agriculture, with the people living in a state of savagery, the land remaining uncultivated and not bearing any fruits. "Dionysos" (that is, Pṛthu) then taught Indians to use weapons; and, after finding the land to be uncultivated and barren, he introduced the use of the plough and gave people the seeds of plants, and also taught them how to harvest and store food and grow grapes.
In the original Indic myth, Pṛthu was first consecrated king and the son of the tyrant Veṇā, under whom the land was wild and uncultivated, similarly to how Scythia was initially an uncultivated desert land when Targī̆tavah first arrived there. Before the first king, Pṛthu, was initiated into kingship, all the plants would wither and the people died from hunger. Pṛthu then milked various forms of agricultural knowledge from the Earth, who had taken the form of a cow, and then he first started the practice of tilling the land using a plough and sought to preserve all the food. Thus, thanks to Pṛthu, the Earth began to bear fruit, cows began to produce milk, there was food, and he was responsible for the beginning of settled life and the foundation of cities, trade, cattle-breeding, the tilling of the land, and for the establishment of truth and lies, that is of laws and justice.
The closest Indic parallel to the acquisition of power by Kolaxšaya through his mastery of the various objects was the ceremony through which the king was consecrated. The itself was initially a yearly ceremony through which the depleted forces of fertility in the world were restored before they would become depleted again by the end of each following year.
During the , the king performed the , that is the "harnessing of offerings into the yoke," through which he "harnessed" the year, itself divided into 12 months each represented by an offering, into the yoke used to till the land so as to usher in the rainy season. During the ceremony, the king was identified with the king of the gods, Indra, whose main role was to provide rain, and Indra was considered to be the one who was directing the plough in the field during the ceremony. Thus, the Indic king was identified with Indra during this sacrifice which ended the year and acquired the thirteenth month, that is the New Year.
The use of the plough and yoke harnessed to bulls to till the land during the , that is for the first time each year and to survey the land, was itself part of the functions of Indo-Iranic kings.
During the ceremony, the Indic king was also identified with the god who protected the law, Varuṇa. This thus represented the king's position as the chief judge of his realm, which made him the embodiment of law and righteousness, and therefore his role as the embodiment of the priestly functions.
The king was also offered a bow with three arrows during the , which represented his masculine royal power and his connection with his heirs.
The cup attached to the belt in the second version of the genealogical myth was also connected to the Indic coronation ritual whereby and holy waters used to anoint the king were prepared in similar vessels which were given to the king.
The plough-and-yoke was necessary for the consecration of kings and was a symbol of royal power, with the first tilling by the king and the symbolic delimitation of boundaries being associated to the use of bulls. The bowl and the arrows were also required for the coronation rite.
The plough-and-yoke, vessel and bow therefore signalled the king as representing the functions of all social classes within himself during the ceremony. These objects held the same function in the Scythian genealogical myth
The axe of Kolaxšaya meanwhile semantically corresponded to the percussive instruments wielded by Indra, who was also the god of thunder and rain, such as his (mace) and (thunderbolt).
The royal wielder of the mace was also connected to the Ṛbhu gods of the airspace, with Indra's being named after Ṛbhukṣan, who was the leader of the Ṛbhu. The Ṛbhu were also blacksmith gods who created the two horses of Indra; the Ṛbhu also accompanied Indra, and rode on the same chariot as him; Ṛbhukṣan also served Indra and both Indra and Ṛbhukṣan offered sacrifices together, even going so far as to merge.
This association to the Ṛbhu connected Indra to blacksmithing, with the blacksmith in ancient mythologies being a sacred figure who was a thunderer and a divine creator who was linked to ploughing and the liberation of the waters.
Non-Iranic parallels
In Greek mythology
The king Cecrops, who, in Greek mythology, was the first king of Athens who had introduced the Athenians to religious rituals and marriage, was an anguipede ancestral figure. Similarly to the Scythian Snake-Legged Goddess, Cecrops was an autochton born from the Earth, and he was human above the waist and a snake below it, which indicated his dual character as being associated with the nether world and death as well as with life and renewal.
In Italic mythology
The myth of the king Italus recorded by Aristotle was similar to that of Kolaxšaya in that it was a myth about the deeds of the first king, Italus, who taught the people to cultivate the land.
In Roman mythology, the story of the encounter of Hercules, who was the Italic equivalent of Hēraklēs, with the thief Cacus exhibits some parallels with the story of Hēraklēs's stay in Scythia: Cacus stole four bulls and four cows from the cattle of Geryon that Hercules was driving; this was a model for the historical sacrifice of cows and bulls at the site where Hercules was believed to have defeated Cacus. Although Cacus, like the Scythian Snake-Legged Goddess, had power over the land where he dwelt, the encounter between Hercules and Cacus in the Roman myth was wholly hostile, unlike the amorous one in the Scythian myth.
In Celtic mythology
The myth of Keltine
A genealogical legend similar to the Scythian genealogical myth existed in ancient Celtic mythology. This myth was later Hellenised by the ancient Greeks living on the southern coasts of Gaul and recorded by various classical authors.
The combination of the various versions of this myth provides a common narrative:
In Keltikē, that is the Celtic country, the king Bretan(n)os had a daughter named Keltinē or Keltō, who fell in love with "Hēraklēs" who was driving the cattle of Gēryōn from Iberia to Tiryns. Keltinē/Keltō stole the cattle of "Hēraklēs" to force him to have sexual intercourse with her, and from their union was born a son named Galatēs or Keltos to whom the mother gave a bow left by "Hēraklēs." Galatēs/Keltos became king after pulling the bow of "Hēraklēs," and the Celts were descended from him.
Another Celtic version adds that the princess, called Pyrene, bore Heracles a serpent for a son. Those legends are very similar to the Scythian genealogical myth, with common elements including "Hēraklēs" driving the cattle of Gēryōn from Iberia to Greece, and then meeting with a local woman who abducted his horses, having sexual intercourse with the woman, and the birth from this union of a son who founded a nation and became king by pulling his father's bow.
The acquisition of the golden objects by Kolaxšaya in the first version of the Scythian genealogical myth, especially, has an exact parallel in the inheritance of the bow of "Hēraklēs" by Galatēs/Keltos in the Celtic genealogical myth, with the latter corresponding to the Celtic inheritance law whereby, when heritage was partitioned between brothers, the youngest would receive the estate, all buildings, 8 acres of land, an axe, a cauldron, and a coulter.
There were nevertheless also some differences between the Scythian and Celtic genealogical myths:
the consort of "Hēraklēs" was the Snake-Legged Goddess in the Scythian myth, while she was a beautiful princess in the Celtic myth;
the horses of the chariot of "Hēraklēs" were stolen in the Scythian myth, while the cattle of Gēryōn that "Hēraklēs" was driving were stolen in the Celtic myth;
three sons were born from the union of "Hēraklēs" and the local woman in the Scythian myth, while only one son was born in the Celtic myth.
Despite their similarities, the exact relationship between the Scythian and Celtic genealogical myths is still unclear.
Mélusine
The fairy Mélusine from mediaeval Celtic folklore also exhibited parallels to the role of the Snake-Legged Goddess in the Scythian genealogical myth. After her husband broke his oath to her and saw her reptilian body, Melusine was forced to leave him.
In Germanic mythology
The motif of the weapon given to the mortals was present in mediaeval Germanic myth, with the transmission of a sword being connected to a prophecy in both the and the ; due to the production techniques and the use of steel, which was a scarce material, swords were seen as symbols of status in mediaeval Germanic societies.
These swords were also seen as magical objects with their own names and personalities, with their power being considered to be of otherworldly origin that was either supernatural or chthonic, and in the myths they were often manufactured by Dwarves. The fate of these swords' owners was linked to them in mysterious and deadly ways, and whoever obtained them also gained the virtues of their previous owners.
In Slavic mythology
Like the Scythian blacksmith-king Kolaxšaya, it was Kyi, who was one of three brothers and a blacksmith, who founded the city of Kyiv in Slavic mythology.
Turkic borrowings
The Scythian genealogical myth was borrowed by certain Turkic peoples who had assimilated the Saka peoples of Central Asia. Such a borrowed version is present in the Uyghur version of the , according to which the ancestor of the Oghuz Turks, Oghuz Qaghan, had two wives.
The first wife of Oghuz Qaghan came down to the earth from the sky in a ray of blue light, and with her he had three sons, named:
Kün (meaning "Sun"),
Ay (meaning "Moon"),
Yultuz (meaning "Star").
Oghuz Qaghan's second wife was first found inside a tree in the middle of a lake, and with her he had three sons, named:
Kök (meaning "Sky"),
Tagh (meaning "Mountain"),
Dëngiz (meaning "Sea").
Oghuz Qaghan's sons from his first wife became the ancestors of the s, while his sons from his second wife became the subjects of the qaghans. This myth is based on the opposition of the celestial and earthly binary whereby the woman from heaven became the ancestress of the rulers and the woman from the earth became the ancestress of the subjects.
Although the celestial characters of the sons of the celestial wife of Oghuz Qaghan correspond to the celestial nature of their mother, the sons of Oghuz Qaghan's earthly wife do not all have earthly characters, and instead represent the three layers of the universe, with Kök (Sky) standing for the celestial realm, Tagh (Mountain) for the earthly realm, and Dëngiz for the marine and chthonic realm.
The narrative of the three brothers representing the three layers of the universe who were born from the earthly maiden did not represent the traditional Turkic cosmology, but instead corresponded to the Iranic one due to having been borrowed from the Saka peoples of Central Asia. Since early Turkic societies were different from Iranic ones, the myth's meaning relating to the origin of social functions was therefore not retained when it was borrowed, due to which the difference between the three brothers did not play any important role in the Turkic legend and even contradicted the myth itself.
References
Sources
Further reading
Accessed 20 June 2023.
Accessed 20 June 2023.
Accessed 20 June 2023.
Hinge, George (2008). "Dionysos and Herakles in Scythia - The Eschatological String of Herodotus' Book 4". In: P. Guldager Bilde and J.H. Petersen (eds.). Meetings of Cultures in the Black Sea Region: Between Conflict and Coexistence. Aarhus: Aarhus University Press. pp. 369–97.
. Accessed 20 June 2023.
Schiltz, Véronique. "Le Roi scythe. Iconographie du pouvoir scythe au IVe s. avant J.-C.". In: Les princes de la protohistoire et l’émergence de l’État. Actes de la table ronde internationale organisée par le Centre Jean Bérard et l'Ecole française de Rome Naples, 27-29 octobre 1994. Rome: École Française de Rome, 1999. pp. 115–123. (Publications de l'École française de Rome, 252).
Ustinova, Yulia. “Aphrodite Ourania of the Bosporus: The Great Goddess of a Frontier Pantheon”. In: Kernos [Online], 11 (1998): 209-226. Online since 21 April 2011, connection on 20 June 2023. URL: http://journals.openedition.org/kernos/1228.
Scythian religion
Iranian mythology
Asian mythology
European mythology
Genealogy
Melusine | Scythian genealogical myth | [
"Biology"
] | 23,850 | [
"Phylogenetics",
"Genealogy"
] |
71,320,302 | https://en.wikipedia.org/wiki/Come%20into%20My%20Cellar | Come into My Cellar, alternatively titled Boys! Raise Giant Mushrooms in Your Cellar!, is a science fiction short story by American writer Ray Bradbury. It was originally published in Galaxy Magazine in October 1962, and was subsequently included in the short-story collection S is for Space.
The story is about an alien invasion in the form of fungi who take over the body and free will of whoever consumes them, and disperse by sending Special Delivery packages to new victims with mushrooms to be grown and eaten.
Ray Bradbury mentioned having the idea for the story while eating steak and mushrooms with a group of editors, and not being taken seriously by them. He then joked that he didn't eat mushrooms for the following years.
Plot summary
Hugh Fortnum wakes up to the noises of his family and neighbour. He opens the window and greets his neighbour Mrs. Goodbody, intent in treating her bushes against bugs and pests, and convinced of being the first line of defence against flying saucers.
Hugh hears the doorbell and walks downstairs to find his wife Cynthia holding a Special Delivery package from New Orleans for their son Tom. The small package is from the Great Bayou Novelty Greenhouse, and contains ‘The Sylvan Glade Jumbo-Giant Guaranteed Growth Raise-Them-in-Your-Cellar-for-Big-Profit Mushrooms’. Tom goes down to the cellar and starts planting the mushrooms. As the advertisement says, they will show fabulous growth within only 24 hours.
Toward noon, Hugh Fortnum is driving to the market when he picks up his friend Roger Willis, a biology teacher. Roger is scared and tells Hugh about his intuitive belief that something is wrong with the world. Hugh asks Roger what to do about it, and Roger tells him to wait and observe the world for a few days. Roger leaves, and Hugh drives away.
Hugh sits on his porch with his wife and asks her if she has had any sort of intuition lately. She ponders the question and answers that she did not, when Tom appears, showing them the remarkable growth of the mushrooms he’s cultivating in the cellar. In just seven hours, hundreds of greyish brown mushrooms are sprouting from the soil. Cynthia feels uneasy, asks if what Tom is growing really are mushrooms and Tom leaves angrily for the cellar. The phone rings and it’s Dorothy, Roger Willis’ wife. She says that her husband is gone, and asks for Hugh’s help.
Hugh goes over to Roger and Dorothy Willis' house and sees that Roger’s clothes are gone. Dorothy and the son Joe are confused about the sudden disappearance of Roger. Before promising Dorothy that he will try to find Roger, Hugh sees Joe walking down to the cellar.
Hugh goes back home to find his neighbour, Mrs. Goodbody, fighting off aphids, waterbugs, woodworms, and now Marasmius oreades. He explains to his wife about the disappearance of Roger Willis when a delivery boy brings him a telegram from Roger, saying that he is in New Orleans and that Hugh must refuse all Special Delivery packages at all costs. Hugh calls the police.
In the evening, the phone rings at the Fortnum’s house. It is Roger, saying he is on a business trip and asking Hugh why he sent the police to find him. He also tells Hugh that his wife and son knew about his trip, and that he will be back in five days. Roger passes the phone to an angry lieutenant, asking Hugh for explanations.
Hugh calls Dorothy, and she confirms that her son received, like all kids in the neighbourhood, a Special Delivery package a few days earlier, the same as Tom received in the morning. Watching a meteor in the sky, Hugh starts to suspect that something invaded Earth. He ponders that an alien invasion would not come by meteors or flying saucers, but by means of spores, seeds, pollens or viruses raining on Earth from space; and he thinks that a spore germinating into a mushroom would not need arms and legs to send itself around via Special Delivery, if it could be eaten by a person, infiltrate their blood and take over their cells. Just like what happened to Roger Willis, concludes Hugh, who became something else after eating the mushrooms grown by his son.
Cynthia goes to bed and Hugh pours himself a glass of milk. In the fridge, he finds a fresh-cut mushroom, left by Tom for his parents to eat after he himself had a mushroom sandwich. Hugh leaves the mushrooms at the bottom of the stairs leading upstairs. He calls to his son Tom who is down in the cellar tending his crop. Tom tells his dad to come down to see the harvest. Hugh goes down into the dark cellar, shutting the door behind him.
Reception
The Master of Arts thesis by Şeyma Karaca discusses the story (with the alternative title "Boys! Raise giant mushrooms in your cellar!") from a perspective of mental metamorphosis and alien invasion.
The "SF Personality" series #24 by Hardy Kettlitz summarizes the story and highlights the increasing paranoia throughout it, giving the interpretation that, at the end, Hugh Fortnum walks into the cellar without knowing what awaits him.
John Booth for Wired included the short story as one of "Ten stories by Ray Bradbury to get you into the Halloween spirit" due to its suspence and lurking menace.
In the essay by Eric S. Rabkin "Is Mars heaven? The Martian chronicles, Fahrenheit 451 and Ray Bradbury's landscape of longing" in "Visions of Mars: Essays on the Red Planet in Fiction and Science", the author highlights how the story, with invaders from outer space taking over the body and the mind of citizens, fits within the narrative of its historical times (Cold War).
Adaptations
Ray Bradbury wrote the Alfred Hitchcock Presents TV show Special Delivery (1959) based on a similar plot.
Under the pen name Luis Peñafiel, Narciso Ibáñez Serrador adapted the story into the two-part episode "La Bodega" for the 1966 Spanish anthology tv series Historias para no dormir.
The story was adapted into the short movie The Ray Bradbury Theater: Boys! Raise Giant Mushrooms In Your Cellar! (1989).
The comic strip Come into My Cellar by English comic artist Dave Gibbons is based on Ray Bradbury's short story
References
External links
Come into My Cellar on the Internet Speculative Fiction Database
Comic strip Come into My Cellar by English comic artist Dave Gibbon on the Internet Speculative Fiction Database
Short stories by Ray Bradbury
Science fiction short stories
Fungi and humans
Fictional fungi | Come into My Cellar | [
"Biology"
] | 1,343 | [
"Fungi and humans",
"Fungi",
"Humans and other species"
] |
71,321,817 | https://en.wikipedia.org/wiki/Carboxylate-based%20metal%E2%80%93organic%20frameworks | Carboxylate–based metal–organic frameworks are metal–organic frameworks that are based on organic molecules comprising carboxylate functional groups.
Divalent Carboxylates
The divalent metal carboxylate based frameworks MOF-5 and HKUST-1 are examples of prototypical MOF materials and triggered a huge growth in the field of metal-organic frameworks. A keyword search for “metal-organic frameworks” registers>1,600 publications in 2010 and >2,000 for 2011, a strong indication of the worldwide interest in this area and indicates that the growth is continuing. More recent work on divalent carboxylates with longer and more complex organic components is pushing the limits of gas adsorption and storage properties with the highest surface areas and lowest densities of all known crystalline materials.
MOF-5 & MOF-177
MOF-5 is an early and heavily studied example of a MOF material. The material is an example of a cubic 3-dimensional extended lattice composed of Zn4O inorganic clusters connected by terephthalate linkers. Each cluster involves 6 carboxylate groups of 6 terephthalate molecules bridging zinc atoms leading to an octahedral type arrangement around the cluster which, when expanded in three dimensions, reproduces the cubic arrangement of the material. The structure is retained upon solvent removal and the literature states that the Langmuir surface area (a monolayer-equivalent surface area) is stated to be of the order of 3000 m2g−1, significantly higher than that of most zeolites and at the time, among the highest of all known materials. One downside to the large open pore structure is the potential for interpenetration of 2 frameworks. In the case of MOF-5 and the IRMOF family of isoreticular structures, if the pore size is sufficient to contain a Zn4O cluster and the dicarboxylate is of sufficient length, then the formation of a second extended lattice can occur within the first. This interpenetration or catenation of two frameworks results in a significant reduction in the porosity as the majority of the void space in the cage is filled with the other framework. Examples of interpenetration are reported for some members of the IRMOF series.
MOF-177 is another example of a MOF material containing the tetrahedral Zn4O cluster but with a more complex and extended tricarboxylate linker. The carboxylate molecule in this case in the large BTB molecule (BTB = benzene-1,3,5-tribenzoic acid). This large yet rigid tri-carboxylate unit connects to the cluster in the same manner as in the MOF-5 structure but as there are three carboxylate units and a triangular geometry, this produces a more spherical porous cage structure rather than the cubic pore geometry in MOF-5. MOF-177 has been shown to have one of the largest surface areas of known materials to date. Literature states a Langmuir surface area value of 4500 m2g−1 with N2 adsorption giving a type I isotherm with adsorption of 1350 mg g-1 between 0.4 and 1 P/P0.50 These values show that MOF-177 is a highly porous open framework MOF material with a 3-dimensionally connected array of porous cages.
HKUST-1
HKUST-1 is another early example of a divalent carboxylate MOF. Reported around the same time as MOF-5, HKUST-1 is a copper ‘paddlewheel’ based MOF where two copper ions form a dimeric unit with four bridging carboxylates creating a square planar geometry around two adjacent copper sites. The two copper ions in the paddlewheel coordinate to the oxygen of two water molecules to create a double square pyramidal geometry for the two metal sites in the hydrated form of the structure. Activation of the material prior to adsorption studies results in the removal of the terminal water molecules resulting in a coordinatively unsaturated metal site. The rigid, porous structure of the HKUST-1 framework combined with the accessibility of the activated metal sites upon dehydration has led to a lot of interest in adsorption, separation and catalysis applications.
CPO-27 / MOF-74
While surface area and pore volume is important to the adsorption properties of MOF materials, another consideration is the availability of coordinatively unsaturated metals sites. The divalent metal carboxylate CPO-27(M) (where M = ) was reported by Dietzel and co-workers, while at a similar time work by Rosi et. al. produced the isostructural zinc analogue, referred to as MOF-74. The divalent metal and 2,5-dihydroxyterephthalic acid linker form a honeycomb like array of hexagonal channels. The inorganic component is a helical chain of edge sharing NiO6octahedra where each metal is bound to two oxygens from hydroxyl groups on the ligand, three oxygens from carboxylate groups and one water molecule. MOF-74 was prepared using DMF as the solvent and as such, has terminal DMF molecules bound to the free metal sites on the chain. The helical chains of CPO-27(Ni) are separated by the planar acid linker. This organic molecule acts as a rigid pillar between chains with each linker bound to three different metal sites from each chain. Removal of the solvent molecules from the terminal metal sites creates five-coordinate metal cations with little freedom to rotate or distort the chain to change the coordination environment. This unfavourable coordination environment means that the activated metal site has a high enthalpy of adsorption and is readily filled by adsorbed guest species. The chain is topologically identical to that of the nickel bisphosphonate STA-12(Ni) but differs upon dehydration where the additional flexibility of the bisphosphonate linker allows the chain to twist and distort reducing the accessibility of the coordinatively unsaturated metal site. The availability of this metal site in the CPO-27 framework has been explored for a number of different adsorption applications involving gases such as CO2, H2 and NO.
Trivalent Carboxylates
Some of the most widely studied of all metal organic frameworks are trivalent metal carboxylate materials. Extensive work in this area has provided an understanding of the crystal chemistry of a wide variety of the trivalent first row transition metals
MIL-47 & MIL-53
The vanadium terephthalate MIL-47, first reported by Barthelet and co-workers, is an example of a metal organic framework consisting of infinite corner sharing metal chains of VO6 octahedra bridged by the linear terephthalate organic linker. This connectivity results in the formation of large diamond shaped channels. The channels in as-prepared vanadium MIL-47 contain some residual guest terephthalic acid and is reported as having the formula VIII(OH)(CO2-C6H4-CO2) and a hydroxide μ2-OH ion forming the infinite chains. Activation of the solid by heating in a tube furnace at 573 K for 24 hours results in deprotonation of the hydroxide on the chains to form a μ2-oxo and oxidation of the vanadium, to give VIVO(CO2-C6H4-CO2) as the formula for the activated material. The activated MIL-47(V) is anhydrous at room temperature under ambient pressure, as the channels are hydrophobic, being lined with phenyl rings and with no accessible metal sites or favourable hydrogen bonding positions the channels are hydrophobic.
MIL-53 was first reported with chromium (Cr3+) and shortly after with aluminium (Al3+) with terephthalic acid as the linker. MIL-53 is isostructural with MIL-47, the main difference is that MIL-53 only contains the trivalent metal and a μ2-hydroxide bridge whereas the activated MIL-47 is the tetravalent V4+ with μ2-oxobridging. As the activated form of the MIL-53 contains the metal hydroxide chains, the channels are hydrophilic with the hydroxide protons available for hydrogen bonding. When activated MIL-53(Cr or Al) is exposed to moisture, X-ray diffraction shows the material adopts a ‘closed’ structure, due to the strong hydrogen bonding interaction between the hydroxyl groups of the inorganic chains and the adsorbed water molecules. As a result of this hydration behavior, the unit cell volume reduces by ~30%, fully reversible upon subsequent dehydration. Such large structural changes, in response to adsorption of gas or solvent molecules, is commonly referred to as ‘breathing’.
Since the initial reports of the chromium and aluminium MIL-53, extensive work has been undertaken in this area, and the range of MIL-53 materials now extends to: Cr3+,Al3+, Fe3+, Ga3+, In3+, and Sc3+.
MIL-68
Work by Barthelet and co-workers also identified MIL-68, another trivalent metal terephthalate. The framework is a polymorph of the MIL-47/MIL-53 structure with the chemical formula, MIIIOH(CO2-C6H4-CO2) initially reported for V3+and later with In3+ and Ga3+. In this case the metal hydroxide chains connect to form two types of unidirectional channels, triangular and hexagonal in shape, creating a‘kagome lattice’ like network of pore channels. The cross-sectional diameters of the triangular and hexagonal channels are 6 Å and 17 Å respectively.
N,N’-Dimethylformamide (DMF) solvent molecules were observed in the smaller triangular channels of as-prepared MIL-68(In) reported by Volkringer et. al, disordered over two positions, with hydrogen bonding between the oxygen of the DMF and the hydroxyl group of the inorganic chain. The solvent was removed by calcination at 200 °C overnight in a furnace. The activated samples were stored under inert atmosphere to prevent rehydration which would lead to hydrolysis and ultimately decomposition of the structure. Adsorption studies on the indium and gallium forms of MIL-68 give a value for the BET surface area of 1117(24) m2 g-1,746(31) m2g−1 and 603(22) m2g−1 for the gallium, indium and vanadium forms respectively. A number of activation procedures were attempted and NMR analysis used to verify complete removal of guest molecules to obtain the surface area results. The BET values suggest that the indium and vanadium analogues were not fully activated prior to adsorption. Notably, a recent computational study of the theoretical surface area, gave a value of 3333 m2g−1 for MIL-68(V) suggesting that there may still be activation issues with all the MIL-68 derivatives, rendering some of the porosity in accessible.
MIL-88
Further study on the metal carboxylate systems of trivalent iron and chromium yielded a series of materials referred to as MIL-88(A-D). First reported as an iron fumarate, and based on the trimeric building unit obtained on the crystallization of iron (and chromium) acetate, MIL-88 is a family of isoreticular materials prepared withdicarboxylate linkers.
Reactions using the metal acetate trimeric building unit are thought to proceed via a ligand exchange mechanism where the acetate of the starting material is replaced with a longer linear dicarboxylate to create the three dimensional framework. MIL-88 is an isoreticular series with increasing length of dicarboxylate forming the same network topology prepared using the fumaric acid (MIL-88A), terephthalic acid (-88B),naphthalene-2,6-dicarboxylic acid (-88C) and 4,4’-biphenyldicarboxylic acid (-88D). The framework consists of both one dimensional channels, and trigonal bipyramidal cages. Solvent exchange experiments on the terephthalate form, MIL-88B, show that large organic molecules such as lutidine and butanol are able to enter the framework and induce an increase in cell volume over the dried material. The three metals in the trimeric cluster share a μ3-O and are bridged to the adjacent metals with four carboxylate groups, leaving a coordinatively unsaturated metal site pointing into the cages within the framework. To maintain charge balance in the material, there must be one negatively charged species on the cluster, either a hydroxide or fluoride (depending on the synthesis conditions) occupying one of the unsaturated metal sites and the other two could be water or exchanged solvent species.
MIL-88(Cr and Fe) also exhibits a breathing behaviour in response to solvent exchange and gas adsorption. The mechanism for the breathing is similar to that observed in the MIL-53 where there is a hinge like motion around the axis of the two oxygen atoms of the carboxylate. The observed expansion and contraction of the unit cell volume is, however, much greater than that observed in MIL-53. As the trimeric units are connected in three dimensions, rather than the columnar rows of terephthalates connecting the chains in MIL-53, the change occurs over all three axes resulting in a cell volume expansion for the terephthalate form (MIL-88B) of 125% from the fully dried form (1500 Å3) to the most open form observed upon methanol solvation (3375Å3).
References | Carboxylate-based metal–organic frameworks | [
"Chemistry",
"Materials_science"
] | 2,986 | [
"Porous polymers",
"Metal-organic frameworks"
] |
71,322,459 | https://en.wikipedia.org/wiki/Kaniadakis%20distribution | In statistics, a Kaniadakis distribution (also known as κ-distribution) is a statistical distribution that emerges from the Kaniadakis statistics. There are several families of Kaniadakis distributions related to different constraints used in the maximization of the Kaniadakis entropy, such as the κ-Exponential distribution, κ-Gaussian distribution, Kaniadakis κ-Gamma distribution and κ-Weibull distribution. The κ-distributions have been applied for modeling a vast phenomenology of experimental statistical distributions in natural or artificial complex systems, such as, in epidemiology, quantum statistics, in astrophysics and cosmology, in geophysics, in economy, in machine learning.
The κ-distributions are written as function of the κ-deformed exponential, taking the form
enables the power-law description of complex systems following the consistent κ-generalized statistical theory., where is the Kaniadakis κ-exponential function.
The κ-distribution becomes the common Boltzmann distribution at low energies, while it has a power-law tail at high energies, the feature of high interest of many researchers.
List of κ-statistical distributions
Supported on the whole real line
The Kaniadakis Gaussian distribution, also called the κ-Gaussian distribution. The normal distribution is a particular case when
The Kaniadakis double exponential distribution, as known as Kaniadakis κ-double exponential distribution or κ-Laplace distribution. The Laplace distribution is a particular case when
Supported on semi-infinite intervals, usually [0,∞)
The Kaniadakis Exponential distribution, also called the κ-Exponential distribution. The exponential distribution is a particular case when
The Kaniadakis Gamma distribution, also called the κ-Gamma distribution, which is a four-parameter () deformation of the generalized Gamma distribution.
The κ-Gamma distribution becomes a ...
κ-Exponential distribution of Type I when .
κ-Erlang distribution when and positive integer.
κ-Half-Normal distribution, when and .
Generalized Gamma distribution, when ;
In the limit , the κ-Gamma distribution becomes a ...
Erlang distribution, when and positive integer;
Chi-Squared distribution, when and half integer;
Nakagami distribution, when and ;
Rayleigh distribution, when and ;
Chi distribution, when and half integer;
Maxwell distribution, when and ;
Half-Normal distribution, when and ;
Weibull distribution, when and ;
Stretched Exponential distribution, when and ;
Common Kaniadakis distributions
κ-Exponential distribution
κ-Gaussian distribution
κ-Gamma distribution
κ-Weibull distribution
κ-Logistic distribution
κ-Erlang distribution
κ-Distribution Type IV
The Kaniadakis distribution of Type IV (or κ-Distribution Type IV) is a three-parameter family of continuous statistical distributions.
The κ-Distribution Type IV distribution has the following probability density function:
valid for , where is the entropic index associated with the Kaniadakis entropy, is the scale parameter, and is the shape parameter.
The cumulative distribution function of κ-Distribution Type IV assumes the form:
The κ-Distribution Type IV does not admit a classical version, since the probability function and its cumulative reduces to zero in the classical limit .
Its moment of order given by
The moment of order of the κ-Distribution Type IV is finite for .
See also
Giorgio Kaniadakis
Kaniadakis statistics
Kaniadakis κ-Exponential distribution
Kaniadakis κ-Gaussian distribution
Kaniadakis κ-Gamma distribution
Kaniadakis κ-Weibull distribution
Kaniadakis κ-Logistic distribution
Kaniadakis κ-Erlang distribution
References
External links
Giorgio Kaniadakis Google Scholar page
Kaniadakis Statistics on arXiv.org
Probability distributions | Kaniadakis distribution | [
"Physics",
"Mathematics"
] | 776 | [
"Functions and mappings",
"Probability distributions",
"Mathematical objects",
"Mathematical relations",
"Statistical mechanics"
] |
71,323,650 | https://en.wikipedia.org/wiki/Holmium%20acetylacetonate | Holmium acetylacetonate is a coordination compound with the formula Ho(C5H7O2)3. This anhydrous acetylacetonate complex is often discussed but unlikely to exist per se. The 8-coordinated dihydrate Ho(C5H7O2)3(H2O)2 is a more plausible formula based on the behavior of other lanthanide acetylacetonates. The dihydrate has been characterized by X-ray crystallography.
Attempts to dehydrate other lanthanide acetylacetonates results in decomposition.
Further reading
References
Holmium compounds
Acetylacetonate complexes | Holmium acetylacetonate | [
"Chemistry"
] | 139 | [
"Inorganic compounds",
"Inorganic compound stubs"
] |
71,324,481 | https://en.wikipedia.org/wiki/Heave%20compensation | Heave compensation is motion compensator technology applied to minimizing the vertical movement of a load supported by lifting gear mounted on a heaving platform. Techniques include active heave compensation and passive heave compensation—the two traditional types of heave compensation—as well as balanced heave compensation. Devices that perform heave compensation are known as heave compensators.
Description
Heave compensation is move compensator technology used to minimize the movement of a load in one direction. This direction is often vertical, as for a load supported by lifting gear mounted on a heaving platform. In offshore drilling, heave compensation is used to reduce the impact on the drill system from motions, including those of waves and the vessel.
Types
There are two traditional basic types of heave compensation are active heave compensation and passive heave compensation. Balanced heave compensation is also used, and differs from the two traditional approaches.
Active heave compensation
Active heave compensation has a control system that uses power to drive the lifting gear to keep the load stabilized along the vertical axis to compensate for any movement of the platform specific point, using power to gain positional accuracy.
Passive heave compensation
Passive heave compensation uses a relatively soft spring which isolates the load from most of the vertical force variation to reduce transmissibility of transient loads.
Balanced heave compensation
Balanced heave compensation converts the non-linear force of a gas spring or hydro-pneumatic spring into an adjustable, substantially linear force supporting the load.
Compensators
A heave compensator is a kind of motion compensator. Whereas most motion compensators will compensate for movement in all directions, the heave compensator will compensate for movement in only one direction, for instance, for vertical movement. In practice, the words motion compensator and heave compensator are used interchangeably. Sensor technologies being used are inertial sensors and GNSS (example: iMAR Navigation) or image processing.
The simplest motion compensator is the anchor chain of a ship. Not only does the anchor prevent the ship from drifting, but the chain itself dampens the movement of the ship due to undulating motion of the waves. Generally, motion compensators are implemented as springs. For very large forces (dozens to hundreds of tonnes), the springs are implemented as gas springs: hydropneumatic devices — a plunger cylinder buffered by a volume of gas.
Examples of heave compensators include:
Drill string compensators
Riser tensioners
Conductor tensioners
Guideline tensioners
More advanced heave compensated systems are often specified as systems with passive heave compensation or active heave compensation or combinations of these. A new approach to advanced heave compensation systems is offered by balanced heave compensation, increasing safety while lowering energy consumption and spring adjustment times.
References
Mechanisms (engineering) | Heave compensation | [
"Engineering"
] | 592 | [
"Mechanical engineering",
"Mechanisms (engineering)"
] |
71,325,287 | https://en.wikipedia.org/wiki/4-Isopropenylphenol | 4-Isopropenylphenol is an organic compound with the formula . The molecule consists of a 2-propenyl group (CH2=C-CH3) affixed to the 4 position of phenol. The compound is an intermediate in the production of bisphenol A (BPA), 2.7 Mkg/y of which are produced annually (2007). It is also generated by the recycling of o,p-BPA, a byproduct of the production of the p,p-isomer of BPA.
Synthesis and reactions
The high-temperature hydrolysis of BPA gives the title compound together with phenol:
The compound can also be produced by catalytic dehydrogenation of 4-isopropylphenol.
4-Isopropenylphenol undergoes O-protonation by sulfuric acid, giving the carbocation, which undergoes a variety of dimerization reactions.
References
4-Hydroxyphenyl compounds
Commodity chemicals
Isopropenyl compounds | 4-Isopropenylphenol | [
"Chemistry"
] | 215 | [
"Isopropenyl compounds",
"Commodity chemicals",
"Functional groups",
"Products of chemical industry"
] |
71,326,091 | https://en.wikipedia.org/wiki/Charles%20T.%20Prewitt | Charles Thompson Prewitt (March 3, 1933 – April 28, 2022) was an American mineralogist and solid state chemist known for his work on structural chemistry of minerals and high-pressure chemistry.
Education and career
Prewitt studied geology at Massachusetts Institute of Technology as an undergraduate and received his PhD in 1962 in crystallography at the same place under the supervision of Martin Buerger, where he worked on the structure determination of wollastonites and pectolites. He moved to DuPont Central Research Laboratory in Wilmington, Delaware, where he worked with Robert D. Shannon to compile the effective ionic radii, which became an important foundation of modern crystal chemistry. Afterwards, Prewitt became a professor at Stony Brook University in 1969. In 1986, he was hired by the Carnegie Institute of Science to head the Geophysics Laboratory until 1998. He later became an adjunt faculty member at University of Arizona.
Honors and awards
Prewitt was a Fellow of the Japan Society for the Promotion of Science in 1983. He was the vice president and president of the Mineralogical Society of America in 1983 and 1984, respectively. He was awarded the Roebling Medal from the Mineralogical Society of America in 2003. He received the inaugural Medal for Excellence from the International Mineralogical Association in 2008.
Bibliography
References
1933 births
2022 deaths
Massachusetts Institute of Technology alumni
University of Arizona faculty
DuPont people
Stony Brook University faculty
American mineralogists
American inorganic chemists
20th-century American chemists
People from Lexington, Kentucky
American chemists
Solid state chemists | Charles T. Prewitt | [
"Chemistry"
] | 313 | [
"American inorganic chemists",
"Solid state chemists",
"Inorganic chemists"
] |
71,329,185 | https://en.wikipedia.org/wiki/Praseodymium%28V%29%20oxide%20nitride | Praseodymium(V) oxide nitride is a compound of praseodymium in the oxidation state of +5 with the chemical formula PrNO. It was first reported in 2000. However, the compound was not verified to have an oxidation state of +5 until 2017. This compound is produced by the reaction of praseodymium metal and nitric oxide in 4K and solid neon. The crystal structure is linear with the praseodymium forming a triple bond with the nitrogen and a double bond with the oxygen. Calculation shows a significant level of f-orbital covalence of Pr-X bonds.
Reactions
Praseodymium(V) oxide nitride further reacts with nitric oxide to form complexes such as NPrO(NO) and NPrO(NO)2 which shows that this compound is a lewis acid. This compound also decomposes to praseodymium(IV) oxide and nitrogen:
PrNO → PrO2 + N2
References
Praseodymium compounds
Nitrides
Oxides | Praseodymium(V) oxide nitride | [
"Chemistry"
] | 217 | [
"Oxides",
"Salts"
] |
71,329,952 | https://en.wikipedia.org/wiki/Department%20of%20Climate%20Change%2C%20Energy%2C%20the%20Environment%20and%20Water | The Department of Climate Change, Energy, the Environment and Water (DCCEEW) is a department of the Australian Government. The department was established on 1 July 2022, superseding the water and environment functions from the Department of Agriculture, Water and the Environment and energy functions from the Department of Industry, Science, Energy and Resources.
The current and inaugural head of the department is the Secretary, David Fredericks.
References
2022 establishments in Australia
Australia, Climate Change, Energy, the Environment and Water
Climate Change, Energy, the Environment and Water | Department of Climate Change, Energy, the Environment and Water | [
"Engineering"
] | 112 | [
"Energy organizations",
"Energy ministries"
] |
77,262,226 | https://en.wikipedia.org/wiki/F%C5%ABrin | A is a small, bowl-shaped Japanese wind chime typically hung during the summer. A piece of paper called tanzaku (短冊) is usually hung from each fūrin to cause it to ring even with just a slight breeze. The sound of the fūrin and the sight of the paper blowing in the wind are seen by many Japanese people as having a cooling effect during the hot Japanese summer.
History
The origins of fūrin are believed to be from the Chinese Tang Dynasty when metal wind chimes were hung in bamboo forests and used to tell fortunes. The word fūrin was first used in Japan during the Heian period when they were hung from eaves, particularly at Buddhist temples, as talismans to ward off evil spirits. They can still be found at many shrines and temples in Japan.
Glass fūrin were first made during the late Edo period. Glass is the most popular material used for fūrin in modern Japan and these glass fūrin are referred to as Edo Fūrin (江戸風鈴). It was also during the Edo period that fūrin were first seen to have cooling properties during the Japanese summer. It is this perceived effect that makes fūrin a summer fūbutsushi (風物詩), or an item characteristic of a certain Japanese season.
During the Edo period, these fūrin, which were made by free glassblowing, were very expensive and primarily used by feudal lords and wealthy merchants. Mass-produced glass fūrin in modern Japan have made them affordable and widespread at Japanese households, but the tradition of free-blowing glass to make fūrin is still practiced by some craftsmen in Japan. Fūrin made from metal and other materials can also still be found throughout Japan.
Fūrin events
During summer in Japan, various events are held throughout the country in which many, sometimes thousands, of fūrin are hung. These fūrin displays, often at temples or shrines, are popular seasonal attractions. Notable events include:
Mizusawa Station, Ōshū, Iwate Prefecture - During summer hundreds of fūrin are displayed at the platform of Mizusawa Station. The sound of these fūrin was chosen as one of the 100 Soundscapes of Japan.
Kawasaki Daishi Fūrin Market - A summer market at Kawasaki Daishi Temple in Kawasaki, Kanagawa Prefecture which sells thousands of fūrin from across Japan.
Kawagoe Hikawa Shrine - about 1,500 fūrin decorate Hikawa Shrine in Kawagoe, Saitama Prefecture during summer.
Gallery
References
Lucky symbols
Wind-activated musical instruments
Objects believed to protect from evil
Amulets
Talismans
Religious objects
Shinto religious objects
Superstitions of Japan
Culture of Japan | Fūrin | [
"Physics"
] | 543 | [
"Religious objects",
"Physical objects",
"Matter"
] |
77,262,906 | https://en.wikipedia.org/wiki/Bufoceratias%20microcephalus | Bufoceratias microcephalus, the small-head toady seadevil, is a species of deep sea marine ray-finned fish belonging to the family Diceratiidae, the double anglers. This is a bathypelagic species which is known only from its holotype which was taken from a depth between in the eastern Indian Ocean off the coast of Java at 8°31.3'S, 110°25.0'E - 8°30.8'S, 110°23.6'E.
References
microcephalus
Deep sea fish
Fish described in 2016
Species known from a single specimen | Bufoceratias microcephalus | [
"Biology"
] | 132 | [
"Individual organisms",
"Species known from a single specimen"
] |
77,263,088 | https://en.wikipedia.org/wiki/List%20of%20Red%20Funnel%20ships | The following list is of Ferries and boats that have been operated by Red Funnel.
Between 1840 and the 1960s, Red Funnel line and its predecessors operated 40 different classic passenger ferries, many of these being paddle steamers. Later ferries sometimes had space allocated for carrying cars but it was not until 1959 that the first purpose-built car ferry was introduced. Classic passenger vessels continued in service until the Balmoral was sold in 1969.
Paddle steamers
Twin-screw steamers
Motor vessels
Car ferries
Although some earlier ferries provided space for cars, Red Funnel introduced its first purpose-built car ferry in 1959. Besides the Raptor-class vessels that are still in service, the following car ferries have been used by Red Funnel:
Fast passenger ferries
The first fast ferry introduced by Red Funnel was the Sea Coach Island Enterprise, a motor cruiser capable of carrying 11 passengers at 20 knots. She was built by the British Power Boat Company in Hythe, and operated from 1933 to 1938.
Hovercraft
In 1968 the company ran trials with an HM2 sidewall hovercraft, number 002, in order to compete with the Seaspeed service which used an SRN6 between Southampton and Cowes. Due to the unreliability of the craft it never entered passenger service. In 1981 Red Funnel acquired a pair of HM2 MkIIIs, GH2019 & GH2024, which were primarily used on the charter service for Vosper Thorneycroft transporting workers from the Isle of Wight to the Woolston yard and back each day. These two craft were disposed of in June 1982 and the charter was subsequently operated by the augmented hydrofoil fleet.
Hydrofoils
The first hydrofoils to operate on the Southampton to Cowes route, and the first in commercial service in the United Kingdom were the Italian-designed Shearwater and Shearwater 2. These were introduced by Red Funnel in 1969, and each seated 54 passengers. They were replaced in 1973 by two 67-seat RH70 hydrofoils, built by Cantière Navale Rodriguez, named Shearwater 3 and Shearwater 4. The latter was delivered some five months after the former and in the interim, a PT20 craft, Fleccia di Reggio, was chartered to stand in. In 1982 Shearwater 5 and Shearwater 6 were added to the fleet. In 1991, with the introduction of the first Red Jet catamarans, the hydrofoils were demoted to backup duties until they were finally withdrawn in 1998.
Red Jets
Tugs and tug tenders
Some tugs also had passenger accommodation to enable them to serve as tenders to liners not berthing in Southampton and to augment the excursion fleet on occasion.
Medina crossing
Hythe Crossing Ferries
In 2023, the Hythe Ferry was acquired by Red Funnel, previous ferries to have operated on the service include:
ex Gosport Ferry, Southsea Queen bought in 1978 to operate cruises and act as a standby vessel for the ferry.
introduced in 1982. She utilised the engines removed from Hotspur III.
was borrowed from the Hurst Castle ferry service in 2013.
removed from service following a collision with the pier on 13 May 2016. As a result of the collision the Maritime and Coastguard Agency withdrew the vessel's passenger safety certificate and vessel was later sold.
was built in 1946 and served on the service until 2014. Hotspur IV was the last in a line of similar ferries. One of her earlier half-sisters, Hotspur II of 1936, saw further service as a ferry on the Firth of Clyde under the name Kenilworth.
References
Ships
Transport lists
Business-related lists
Maritime history | List of Red Funnel ships | [
"Physics"
] | 728 | [
"Physical systems",
"Transport",
"Transport lists"
] |
77,263,284 | https://en.wikipedia.org/wiki/Syntrichia%20caninervis | Syntrichia caninervis, also known as steppe screw moss, is a desert moss species distributed throughout the world. As an extremophile, it is able to withstand desiccation under dry conditions with little access to water and is commonly found in hypolithic communities. It makes use of a novel adaptation to the desert environment to harvest and collect water sources such as dew, fog, snow, and rain, using tiny hairs instead of roots. In laboratory experiments, S. caninervis has shown the ability to survive in a simulated Martian environment.
Description
The plant was first described by English bryologist William Mitten (1819–1906) to the Linnean Society of London in May 1858, with a description published in their journal in February 1859. It belongs to the Syntrichia genus and the Pottiaceae family. It is commonly known as steppe screw moss.
Distribution and habitat
S. caninervis has a widespread global distribution and is an extremophile commonly found in extreme desert environments and hypolithic communities with the capacity to withstand desiccation under dry conditions. It has been observed growing in China, Mongolia, Siberia, central and southwestern Asia, Europe, and North America. In Tibet, Antarctica, and circumpolar regions, it is part of the biological soil crust, which is a resilient type of ground cover often found in arid lands. In North America, the plant is found throughout the western and northwestern United States and in two western Canadian provinces. In the United States, it is found as far east as New Mexico, Colorado, Wyoming and Montana, all the way through Idaho, Utah, Arizona, and Nevada, and as far west as California, Oregon, and Washington. Two of the most common plant communities in the United States are found in the Mojave Desert and in the Columbia River drainage basin. In Canada, it is found in British Columbia and Alberta.
Extremophile characteristics
Drought tolerance
S. caninervis is well-known for its ability to tolerate drought conditions, making it well-adapted to desert environments. Among these adaptions is its tiny hairs on the leaves that allow it to exploit multiple different sources of water, such as dew, fog, snow, and rain. Another example is its ability to photosynthesize once remoistened after desiccation.
Extreme temperature tolerance
Research has shown that S. caninervis can survive freezing temperatures as low as (in liquid nitrogen) for up to 30 days. It has also demonstrated the ability to withstand storage at for up to 5 years. In both cases, the moss was able to regenerate upon thawing, with dehydrated specimens showing faster recovery compared to hydrated ones.
Radiation resistance
S. caninervis exhibits remarkable tolerance to gamma radiation. It can survive exposure to doses of up to 500 Gy, which is lethal to most plants and far exceeds the lethal dose for humans (around 50 Gy). Some studies have even suggested that exposure to 500 Gy of gamma radiation may promote the plant's growth.
Simulated Martian conditions
In laboratory experiments, S. caninervis has demonstrated the ability to survive simulated Martian conditions. These conditions included an atmosphere composed of 95% CO₂, temperature fluctuations between , high levels of UV radiation, and low atmospheric pressure. Dried moss plants achieved a 100% regeneration rate within 30 days after being subjected to these conditions for up to 7 days.
Varieties
The Global Biodiversity Information Facility lists the following five varieties for Syntrichia caninervis:
Syntrichia caninervis var. abranchesii (Luisier) R.H.zander
Syntrichia caninervis var. astrakhanica Ignatov, Ignatova - Suragina
Syntrichia caninervis var. caninervis Mitt.
Syntrichia caninervis var. gypsophila (J.J.Amann ex G.Roth) Ochyra
Syntrichia caninervis var. pseudodesertorum (Vondr.) M.T.Gallego
References
Extremophiles
Pottiaceae
Plants described in 1877 | Syntrichia caninervis | [
"Biology",
"Environmental_science"
] | 824 | [
"Organisms by adaptation",
"Extremophiles",
"Environmental microbiology",
"Bacteria"
] |
77,264,320 | https://en.wikipedia.org/wiki/International%20Development%20and%20Early%20Learning%20Assessment | The International Development and Early Learning Assessment (IDELA) is a method of measuring early development in children at a pre-primary school level.
It was developed for Save the Children between 2011 and 2015.
Background
Cognitive, socio-emotional and physical development during early childhood is crucial to the child's ability to achieve their potential, and to the social and economic health of society as a whole.
However, poverty, stunting and lack of intellectual stimulus in low- and middle-income countries damage early development of almost half of all children aged 3 to 4, which will affect them through their lives.
One of the main reasons is lack of access to early childhood education programs, particularly for poor, rural families.
Existing tools for ECCD measurement had mostly been used in high-income countries, and were hard to adapt to poorer countries.
Often they were costly, and many had limitations such as measuring only one skill or age group, or relying on reports from parents or teachers rather than direct measurement.
Objectives
Before IDELA was developed there were no tools for measuring early Early Childhood Care and Development (ECCD) in low and middle income country that balanced the needs for consistency across different countries, ease of use and psychometric rigor.
IDELA was to be a feasible, holistic, rigorous, open source instrument that ccould easily be adapted to different societies.
It would support continuous program improvement across the many field sites of Save the Children and their partners, increase accountability among ECCD initiatives, and provide data about ECCD outcomes that governments and agencies could use to identify and scale up successful ECCD programs.
Development
Development of IDELA began in 2011 based on four early childhood development domains, drawn from existing standards for early childhood education: physical, language/literacy, numeracy/cognitive and social-emotional.
Over 65 items were considered at first, but these were reduced to 33 during qualitative review.
Between 2013 and 2015 data was collected from 11 sites in different countries.
Although there were limitations to the approach, results show that IDELA is a practical and rigorous method of measuring learning and development before children begin their primary schooling.
Assessment approach
Children from 42 to 78 months old can be assessed in about 30 minutes.
A trained assessor sits with the child, follows a scripted protocol for each test and observes the child's response.
After six of the most challenging tests, and after the child interview, the assessor records whether the child was persistent, motivated and attentive in trying to complete the task.
Materials needed are a pencil, blank paper, small items for counting (such as beans or buttons), nine picture cards related to eight items on the assessment, and
a storybook that contains pictures and text.
Skills assessed are:
Results
A 2019 study of IDELA results in Afghanistan, Bolivia, Ethiopia, Uganda and Vietnam confirmed that IDELA was useful for evaluating programs and monitoring progress within a country, but found it did not give a valid basis for comparison between countries.
A study published in 2021 used data from Ghana to test how well IDELA predicted future skills in reading, as measured by the Early Grade Reading Assessment (EGRA), and in mathematics as measured by the Early Grade Mathematics Assessment (EGMA).
Results showed strong correlation, with scores in the Emergent Literacy domain a strong predictor of EGRA scores, and the scores in the Emergent Numeracy domain a strong predictor for EGMA scores.
See also
Assessment of basic language and learning skills
Educational psychology
References
Sources
Child development
Educational psychology
Behaviorism | International Development and Early Learning Assessment | [
"Biology"
] | 713 | [
"Behavior",
"Behaviorism"
] |
77,264,532 | https://en.wikipedia.org/wiki/Bambi%20%28software%29 | Bambi is a high-level Bayesian model-building interface written in Python. It works with the PyMC probabilistic programming framework. Bambi provides an interface to build and solve Bayesian generalized (non-)linear multivariate multilevel models.
Bambi is an open source project, developed by the community and is an affiliated project of NumFOCUS.
Etymology
Bambi is an acronym for BAyesian Model-Building Interface.
Library features
Model specification using a Wilkison-like formula style
Bayesian inference using MCMC and Variational Inference methods
Interface with ArviZ, as Bambi returns an object
Model interpretation via conditional adjusted comparisons, predictions, and slopes
A wide array of response families
Default priors that the users can modify if needed
See also
Stan, a probabilistic programming language for statistical inference written in C++
References
External links
2016 software
Computational statistics
Free Bayesian statistics software
Monte Carlo software
Numerical programming languages | Bambi (software) | [
"Mathematics"
] | 195 | [
"Computational statistics",
"Computational mathematics"
] |
77,264,849 | https://en.wikipedia.org/wiki/Xylaria%20terricola | Xylaria terricola is a species of terrestrial fungus known from tropical Asia. It produces an asexual branching structure with a single stem as an anamorph and no teleomorph or sexual state has been recorded. While other Xylaria species have been found to have termitophilous associations, there is no evidence of X. terricola being in any such association and grows out of soil.
The species was described from Taiwan in 2017 as arising from the soil with a main axis to about 2-5 cm height. There is repeated branching of the structures ending in gray conidium bearing parts. The stipe is black and glabrous with the interior gray to brown. The species is known only from the anamorph and no teleomorphic structures have been observed. The stromata resemble that of Xyloroemium flabelliformis and while most Xylaria produce anamorph and teleomorphs from the same stromata, it has been suggested that the teleomorph may possibly arise from separate stromata as in Xyloroemium. Several Xylaria species are known to be associated with termite nests, growing from the fungus combs of the termites, but many grow on rotting wood and other substrates. No specific substrate was traceable in Xylaria terricola and it appears to grow in soil. The termitophilic Xylaria species are placed in the subgenus Pseudoxylaria. DNA sequence analysis places Xylaria terricola within the termitophile clade.
References
Xylariales
Fungus species
Fungi described in 2017
Fungi of Asia
Species described in 2017 | Xylaria terricola | [
"Biology"
] | 341 | [
"Fungi",
"Fungus species"
] |
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