id int64 39 79M | url stringlengths 31 227 | text stringlengths 6 334k | source stringlengths 1 150 ⌀ | categories listlengths 1 6 | token_count int64 3 71.8k | subcategories listlengths 0 30 |
|---|---|---|---|---|---|---|
77,265,896 | https://en.wikipedia.org/wiki/Cyclohexane-1%2C2%2C3%2C4%2C5%2C6-hexol | Cyclohexane-1,2,3,4,5,6-hexol is a family of chemical compounds with formula , whose molecule consists of a ring of six carbon atoms, each bound to one hydrogen atom and one hydroxyl group (–OH). There are nine stereoisomers, that differ by the position of the hydroxyl groups relative to the mean plane of the ring. All these compounds are sometimes called inositol, although this name (especially in biochemistry and related sciences) most often refers to a particular isomer, myo-inositol, which has many important physiological roles and medical uses.
These compounds are classified as sugars, specifically carbocyclic sugars or sugar alcohols, to distinguish them from the more common aldoses like glucose. They generally have sweet taste.
These compounds form several esters with biochemical and industrial importance, such as phytic acid and phosphatidylinositol phosphate,
Isomers and structure
The nine stereoisomers of cyclohexane-1,2,3,4,5,6-hexol are distinguished by prefixes: myo-, scyllo-, muco-, -chiro-, -chiro-, neo-, allo-, epi-, and cis-inositol.
As their names indicate, - and -chiro inositol are chiral, a pair enantiomers (mirror-image forms). All the others are meso compounds (indistinguishable from their mirror images).
{|
|-
|
|
|
|- align=center
| myo-
| scyllo-
| muco-
|-
|
|
|
|- align=center
| neo-
| allo-
| epi-
|-
|
|
|
|-
| cis-
| D-chiro-
| L-chiro-
|}
Racemate
The designation rac-chiro-inositol has been used for the racemic mixture (racemate) of equal parts of the two chiro isomers. It crystallizes as a single phase, rather than separate D and L crystals, that melts at 250 °C (which is 4–5 °C higher than the melting point of the pure enantiomers) and decomposes between 308 and 344 °C. The crystal structure is monoclinic with the group. The crystal cell parameters are a = 1014.35 pm, b = 815.42 pm, c = 862.39 pm, β = 92.3556°, Z = 4. The cell volume is 0.71270 nm3, or about 0.178 nm3 per molecule (which is a bit smaller than the typical volumes of other isomers).
Ring conformation
As in cyclohexane, the C6 ring of these compounds can be in two conformations, "boat" and "chair". The relative stability of the two forms varies with the isomer, generally favoring the conformation where the hydroxyls are farthest apart from each other.
Melting points
Some of the stereoisomers crystallize in more than one polymorph, with different densities and melting points — which range from 225 °C for myo-inositol to about 360 °C for polymorph "B" of scyllo-inositol. There is a clear correlation between the melting points and the number and type of chains of hydrogen-bonded hydroxyls.
Biochemistry
All isomers except allo- and cis- occur in nature, although myo-inositol is substantially more abundant and important than the others.
In humans, myo-inositol is synthesized mostly in the kidneys, from glucose 6-phosphate. Small amounts of myo-inositol are then converted by a specific epimerase to -chiro-inositol, which is an important messenger molecule in insulin signaling.
A 2020 study found detectable amounts of epi-, neo-, chiro-, scyllo-, and myo-inositol in the urine of women, pregnant or not. Concentrations of myo and scyllo increased significantly in the third trimester of pregnancy, with scyllo varying between 20% and 40% of myo. Concentrations of epi, neo, and chiro were always a few percent of those of myo, except that chiro- reached 20% of myo in the second trimester of pregnancy.
The bacterium Bacillus subtilis can metabolize myo-, scyllo-, and D-chiro-inositol.and convert to and from these three isomers.
Phytic acids
Plants synthesize inositol hexakis-dihydrogenphosphate, also called phytic acid or IP6, as a storage of phosphorus Inositol penta- (IP5), tetra- (IP4), and triphosphate (IP3) are also called "phytates"
References
External links | Cyclohexane-1,2,3,4,5,6-hexol | [
"Chemistry"
] | 1,065 | [
"Inositol",
"Signal transduction"
] |
77,268,639 | https://en.wikipedia.org/wiki/Termitophile | Termitophiles are macro-organisms adapted to live in association with termites or their nests. They include vertebrates, invertebrates and fungi and can either be obligate termitophiles (those that cannot live without the termites) or non-obligate termitophiles (those that can live independently and make use of the termite nests facultatively or opportunistically). Termitophiles may spend a just a part or the whole of their lifecycle inside a termite nest. The term termitariophily has been suggested as a term to describe the situation where a foreign organism merely uses the termite nest.
Termites live in colonies and construct nests whose environments are controlled. The temperature, humidity, and other conditions inside the nests may be more favourable than the outdoor environment for the termitophiles while potentially also making use of the food resources within the nest, including the fungi grown by the colony or the eggs or larvae being reared.
Termitophilous insects avoid the defenses of the termite colony through one or more of a number of adaptations including having a rounded and smooth body, having bristles (often yellow) on their body surface, masking their odor to avoid detection, exuding chemicals from their body that the termites find pleasing, or by appearing like inanimate objects or mimicking termites.
Insects
A number of species of staphylinid beetles are known to be termitophiles. Cretotrichopsenius burmiticus has been described from 99 million year old Burmese amber and shows termitophilous adaptations. Some like Trichopsenius frosti and Xenistusa hexagonalis are known to follow the trail pheromones of their termite host Reticulitermes virginicus. Trichopsenius frosti also has a cuticular hydrocarbon profile closely matching that of its host. Staphylinid termitophiles mostly in the subfamily Aleocharinae curl their abdomen over their body. The abdomen may also show enlargement of physogastry and in a few species there are protruding appendages that mimic the body structure of a termite. The Australian species Austrospirachtha mimetes and Austrospirachtha carrijoi have abdomen resembling termites. Similar adaptations are seen in the South American Thyreoxenus alakazam and the African Coatonachthodes ovambolandicus.
A subfamily of scarab beetles, the Termitotroginae, are small, blind, and with reduced antennae. The genus Termitotrox (includes Aphodiocopris) is known from the fungus combs of termites in India and Africa. They are thought to be obligate termitophiles.
Some flies in the family Phoridae are termitophilous and grow as larvae within the termite nests. Some species have larvae that feed on the fungus comb while others are termite endoparasites or predators.
Fungi
Termite nest specific fungi include the Basidiobolus, Antennopsis, and some species of Xylaria. Several species of Termitomyces are grown intentionally as food by termites within their comb.
See also
Myrmecophiles
Symphiles
Inquiline
References
Symbiosis
Termites | Termitophile | [
"Biology"
] | 686 | [
"Biological interactions",
"Behavior",
"Symbiosis"
] |
77,268,780 | https://en.wikipedia.org/wiki/Lofting%20coordinates | Lofting coordinates are used for aircraft body measurements. The system derives from the one that was used in the shipbuilding lofting process, with longitudinal axis labeled as "stations" (usually fuselage stations, frame stations, FS), transverse axis as "buttocks lines" (or butt lines, BL), and vertical axis as "waterlines" (WL). The lofting coordinate frame is similar, but not the same as aircraft principal axes used to describe the aircraft flight. For the US-manufactured aircraft the ticks on the axes are labeled in inches, (for example, WL 100 is 100 inches above the base waterline).
Fuselage station
Fuselage stations are traditionally nonnegative, thus the origin is located at the nose of the plane or, sometimes, ahead of it. When compared to the coordinates used for aeromechanics, the fuselage stations are measured in the opposite direction than the ticks on the x-axis (and might not be aligned at all, if the wind-aligned coordinate system is used to describe the flight). Some manufacturers use the designation "body stations", with the corresponding abbreviation BS.
Waterline
Per the US Air Force Airframe Maintenance and Repair Manual (1960), a horizontal waterline extends from the nose cone of the aircraft to the exhaust cone. The base line of the aircraft is designated as waterline 0 (zero). The location of this base line varies on different types of aircraft. However. the planes of all waterlines above and below the zero waterline are parallel. The waterline number (WL or W.L.) in the US is expressed in inches, values increase upwards. Two typical alignments for the base line are the tip of the nose (negative WL are possible) or the "nominal ground plane" (measurements will be nonnegative).
Butt line
Butt line ticks increase to the right of the pilot with the origin at the centerline. When compared to the (right-handed) aeromechanics coordinate systems, the direction of the butt line is opposite to the y-axis.
Other
Many other reference points are used, especially on a large aircraft:
Aileron station (AS), distance from the inboard edge of an aileron;
Flap station (KS), distance from the edge of the flap;
Nacelle station (NS);
Elevator station (ES);
Vertical stabilizer station (VSS).
References
Sources
Aerospace engineering | Lofting coordinates | [
"Engineering"
] | 503 | [
"Aerospace engineering"
] |
77,269,045 | https://en.wikipedia.org/wiki/Russian%20Tsunami%20Warning%20System | Russian tsunami warning system (), also known as Russian tsunami warning service (), is a tsunami warning system in the Russian Far East which is operated and maintained by the Geophysical Service of the Russian Academy of Sciences together with the Far Eastern Regional Research Hydrometeorological Institute (). It is subordinated to the Federal Service for Hydrometeorology and Environmental Monitoring. The Russian tsunami warning system is known under the Russian acronym FP RSCHS-Tsunami ().
History
The Russian tsunami warning system development began in 1956 to 1959. This followed the tsunami and damage which occurred during the 1952 Severo-Kurilsk earthquake. After this, a government decree was issued for the organization of a tsunami warning service. Since 1956, the seismic part of the work was carried out by the Yuzhno-Sakhalinsk seismic station.
In 2003, following the creation of the Unified State System for the Prevention and Elimination of Emergency Situations (RSChS; (), the tsunami warning service received the status of a functional subsystem of the unified system with the acronym FP RSChS-Tsunami ().
In the second half of 2000, the system began a modernization process which included the deployment of new buoys.
Operations
The Russian tsunami warning system includes a network of seismological stations, a hydrophysical (level) network, tsunami warning centers, and a communication system for tsunami warnings. System components are located in Sovetskaya Gavan, Nevelsk, Rudnaya Pristan, Vladivostok, Nakhodka, Preobrazhenye, Uglegorsk, Poronaysk, Starodubskoye, Kholmsk, Korsakov, Cape Crillon, Yuzhno Kurilsk and Vodopadnaya.
See also
Search and rescue in Russia
Civil defense in Russia
Russian System of Disaster Management
External link
- Russian tsunami warning system
References
Warning systems
Russian warning system
Ministry of Emergency Situations (Russia)
Emergency population warning systems | Russian Tsunami Warning System | [
"Technology",
"Engineering"
] | 405 | [
"Warning systems",
"Emergency population warning systems",
"Safety engineering",
"Measuring instruments"
] |
77,269,960 | https://en.wikipedia.org/wiki/Manuel%20Bibes | Manuel Bibes, born on July 15, 1976, in Sainte-Foy-la-Grande, is a French physicist specializing in functional oxides, multiferroic materials, and spintronics. He is currently a Research Director at the National Center for Scientific Research (CNRS).
Biography
After earning an engineering degree from the Institut National des Sciences Appliquées de Toulouse in 1998, Bibes completed his Ph.D. under the supervision of Josep Fontcuberta at the ICMAB, at the Autonomous University of Barcelona in 2001, focusing on thin manganite films and their application in spintronics. His PhD was followed by a postdoctoral fellowship at the Joint Physics Unit CNRS/Thales (currently known as Laboratory Albert Fert) under the guidance of Prof. Albert Fert. Bibes joined the CNRS in 2003 at the Institute of Fundamental Electronics, now known as the Center for Nanoscience and Nanotechnology (C2N). Afterwards he completed research stays at MIT and the University of Cambridge as a visiting researcher and joined the Laboratory Albert Fert at 2007. All his research publications are listed in Google Scholar.
Throughout his career, Bibes has been a leader in research of multiferroic materials (which simultaneously exhibits magnetic and ferroelectric properties) and their utilisation in electrical control of magnetism. In 2009, his team discovered the phenomenon of giant tunnel electroresistance in ferroelectric tunnel junctions (results published in Nature) demonstrating their potential as artificial synapses. In 2016, in collaboration with the Spintec laboratory, he demonstrated that non-magnetic oxide interfaces can be used as ultrasensitive spin detectors. This findings led to a collaboration with Intel for the development of a new type of energy efficient transistor (MESO) aimed at replacing the current transistors based on CMOS technology. Since 2018, Manuel Bibes has been recognized as a Highly Cited Researcher by Clarivate Analytics. In June 2022, along with Agnès Barthélémy, Ramamoorthy Ramesh and Nicola Spaldin, he received the Europhysics Prize from the European Physical Society for their significant contributions to the fundamental and applied physics of multiferroic and magnetoelectric materials. In October 2024, he co-founds the start-up company Nellow, together with Laurent Vila and Jean-Philippe Attané from Spintec. Nellow aims to develop and commercialize chips with an ultralow power consumption for logic and artificial intelligence.
Awards and honors
Europhysics Prize, European Physical Society (2022)
ERC Advanced Grant, European Research Council (2019)
Friedrich Wilhelm Bessel Research Award, Alexander von Humboldt Foundation (2018)
Descartes-Huygens Prize, French Academy of Sciences and Royal Netherlands Academy of Arts and Sciences (2017)
Fellow of American Physical Society, APS (2015)
ERC Consolidator Grant, European Research Council, ERC (2014)
EU-40 Materials Prize, European Materials Research Society, EMRS (2013)
Extraordinary Doctorate Award, Autonomous University of Barcelona (2001)
Selected lectures and talks
Electric-field control of magnetism in oxide heterostructures (Seminar at Collège de France, May 30, 2017)
A journey through the oxide world (a talk at French Academy of Sciences, February 20, 2018)
References
External links
Official Website
Materials science
Condensed matter physicists
Oxides
Thin film deposition
21st-century French physicists
1976 births
Living people | Manuel Bibes | [
"Physics",
"Chemistry",
"Materials_science",
"Mathematics",
"Engineering"
] | 708 | [
"Applied and interdisciplinary physics",
"Condensed matter physicists",
"Thin film deposition",
"Coatings",
"Thin films",
"Materials science",
"Oxides",
"Salts",
"Condensed matter physics",
"nan",
"Planes (geometry)",
"Solid state engineering"
] |
77,270,074 | https://en.wikipedia.org/wiki/NGC%203200 | NGC 3200 is a large spiral galaxy located in the constellation Hydra. Its velocity relative to the cosmic microwave background is 3,877 ± 25 km/s, which corresponds to a Hubble distance of 57.2 ± 4.0 Mpc (~187 million ly). NGC 3200 was discovered by American astronomer Edward Singleton Holden in 1882.
The luminosity class of NGC 3200 is III and it exhibits a broad HI line.
To date, 21 non-redshift measurements give a distance of 43.086 ± 12.631 Mpc (~141 million ly) which is within the Hubble distance values. Note, however, that the NASA/IPAC database calculates the diameter of a galaxy using the average value of independent measurements, when they exist, and that consequently the diameter of NGC 3200 could be about 116.4 kpc (~380,000 ly ) if the Hubble distance were used to calculate it.
Supernovae
One supernova has been observed in NGC 3200: SN 1953D (type unknown, mag. 19.5) was discovered by Chai on 8 March 1953.
See also
List of NGC objects (3001–4000)
External links
NGC 3200 at NASA/IPAC
NGC 3200 at SIMBAD
NGC 3200 at LEDA
References
030108
210
Spiral galaxies
Hydra (constellation)
3200
Astronomical objects discovered in 1882 | NGC 3200 | [
"Astronomy"
] | 291 | [
"Hydra (constellation)",
"Constellations"
] |
77,270,675 | https://en.wikipedia.org/wiki/D%E1%BA%A7u%20Ti%E1%BA%BFng%20Lake | Dầu Tiếng Lake is an artificial lake in the three provinces of Tây Ninh, Bình Dương, and Bình Phước in the Southeast region, Vietnam. The lake was formed by damming the upper reaches of the Saigon River, making it the largest irrigation reservoir in Vietnam and Southeast Asia. Construction of the lake began in 1981 after surveys were conducted starting in 1976. The project was completed with over 100 million USD in funding, which the Vietnamese government borrowed from the World Bank, making it the first project in Vietnam to be built using US dollars since the Reunification of Vietnam on April 30, 1975.
Before construction, the lake's development sparked considerable debate among the leaders of Tây Ninh province regarding the choice of the lake's name and the project's feasibility. Nevertheless, the construction proceeded. Since 2017, Dầu Tiếng Lake has been classified as a project of national security importance due to concerns that a dam breach would affect the Ho Chi Minh City area. As of 2022, Dầu Tiếng Lake is managed by the Southern Irrigation Exploitation One Member Limited Liability Company under the management of the Ministry of Agriculture and Rural Development.
In 2005, along with Black Virgin Mountain, Dầu Tiếng Lake was selected to appear in the central part of the logo of Tây Ninh province.
Overview
Dầu Tiếng Lake spans across four districts: Dầu Tiếng (Bình Dương Province), Dương Minh Châu, Tân Châu (Tây Ninh Province), and Hớn Quản (Bình Phước Province) with a surface area of up to 270 km² and a total capacity of 1.58 billion m³ of water. The lake is located 20 km northeast of Tây Ninh city and 70 km north of Ho Chi Minh City. Formed by damming the upper reaches of the Saigon River, its main purpose is to regulate water flow into the Saigon River and provide irrigation for over 100,000 hectares of agricultural land in Tây Ninh and neighboring provinces such as Bình Dương, Ho Chi Minh City, and Long An. The Dầu Tiếng irrigation system consists of three main canals: East Canal, West Canal, and Tân Hưng Canal, which distribute water through over 1,550 km of branch canals in various localities. Additionally, the lake is used by local residents for aquaculture.
The project is regulating water to serve 93,000 hectares of land in Tây Ninh, including the districts of Tân Biên, Châu Thành, Bến Cầu, Dương Minh Châu, Gò Dầu, the town of Hòa Thành, Trảng Bàng, and the city of Tây Ninh; in Củ Chi district, Ho Chi Minh City; and in Đức Hòa district, Long An province.
History
Survey
After the unification of Vietnam in 1975, the government of the Socialist Republic of Vietnam decided to establish the Southern Irrigation Design Survey Team. Initial maps of the land for planning were adapted from the 1:100,000 maps of the Republic of Vietnam government. In 1976, Phạm Hùng, the Deputy Prime Minister of Vietnam, launched the movement "The entire population and army to undertake irrigation works" with the philosophy that "Irrigation is the foremost measure to rejuvenate the country." During this period, many officials from the North were sent to the South to survey and construct the lake, including Nguyễn Xuân Hùng from the Survey Design Institute (Ministry of Water Resources), who was the chief designer of the project. During the survey, seven officials died after stepping on mines in what is now the lake area. Before the official construction, some rubber plantation owners had intended to build a lake in the area for recreational purposes.
Before the official construction, many auxiliary dams were built by the Vietnamese military starting in 1977.
Construction
The Dầu Tiếng irrigation project was approved by the Prime Minister in 1979 and commenced construction on April 29, 1981, with a total investment of 110 million USD at Thuận Bình hamlet, Truông Mít commune, Dương Minh Châu district, Tây Ninh province, in the presence of Deputy Prime Minister Huỳnh Tấn Phát. At that time, the project faced opposition from Tây Ninh province leaders due to land concerns, as two-thirds of the lake's area was in Tây Ninh, but it was named after Dầu Tiếng, a location in Bình Dương. The opposition was so strong that Nguyễn Văn Tốt, the then-Secretary of Tây Ninh province, instructed all provincial agencies not to receive the Ministry of Water Resources or discuss the Dầu Tiếng project, including the Chairman of the Provincial People's Committee. According to Nông nghiệp newspaper, Minister of Water Resources Nguyễn Thanh Bình was even accused by Tốt to the Central Secretariat of fearing sabotage by the CIA. To placate Tây Ninh, Prime Minister Phạm Hùng named the lake Dầu Tiếng – Tây Ninh. However, Đặng Văn Thượng, the Deputy Secretary of the Provincial Party Committee and Chairman of the Provincial People's Committee of Tây Ninh, supported the project. At its peak, the construction involved up to 36,300 workers, with a minimum of 7,200 workers. Despite the initial opposition from the province, the project saw "significant contributions from the youth and people of Tây Ninh" after Thượng and his officials mobilized the public to dig canals and build the lake.
The capital for constructing the reservoir is said to have come from a preferential loan of over US$100 million from the World Bank, which was chaired at the time by Robert Strange McNamara. McNamara was a former United States Secretary of Defense and considered the "chief architect" of the Vietnam War. This was also the first loan successfully secured by the State of the Socialist Republic of Vietnam, making this project the first to be constructed with US dollars after 1975. The construction workforce at that time consisted of young people, with the number reaching tens of thousands at its peak. According to statistics from the Tay Ninh provincial youth union, by the time the project was put into operation, Tay Ninh and neighboring provinces and cities had mobilized over 450,000 youth members, completed nearly 15 million workdays, excavated more than 11.6 million cubic meters of earth, and constructed nearly 54,000 cubic meters of concrete and masonry, building thousands of kilometers of canals and thousands of structures along the canals. The reservoir was also built in the context of Vietnam being Khmer Rouge attacked on its border by Cambodia.
To obtain the vast area in 1982, thousands of households in Lộc Ninh commune, Dương Minh Châu district, gave up their land and moved to new residences in the Truông Mít and Bến Củi communes. On July 2, 1984, the reservoir began storing water, and on January 10, 1985, the Dầu Tiếng irrigation system with its two main canals, East and West, officially started operation. In 1985, right at the construction site, Thân Công Khởi, a former operator of a self-propelled scraper who participated in building the main dam and later the West canal (one of the two main arteries of the Dầu Tiếng reservoir), was awarded the title of Hero of Labor by the Chairman of the State Council Trường Chinh. He was the only person among the half a million workers to receive this title. During the 1985–1986 period, the reservoir was substantially completed to deliver water to Củ Chi district, with an annual flow of about 135 million cubic meters of water. From 1996 to 1999, the Tân Hưng canal was constructed to direct water from the Dầu Tiếng reservoir to irrigate the southern communes of the two districts Tân Châu and Tân Biên. In 2012, the Phước Hòa irrigation reservoir and canal system became operational, transferring water from the Bé River to the Sài Gòn River, thereby supplementing the water for the Dầu Tiếng reservoir. Thus, this is an irrigation project that transfers water from one river to another, with one reservoir replenishing another.
Activities
Since June 6, 2017, the Prime Minister and the Ministry of Public Security have deployed officials to Tay Ninh to decide to include the Dau Tieng water reservoir project in the list of important projects related to national security. By June 2019, the first solar power plant was established on the submerged area within the Dau Tieng reservoir. Upon completion, the plant became the largest clean energy project in Southeast Asia. In 2021, the Ministry of Agriculture and Rural Development assigned the reservoir's management company to implement a project to invest in, repair, and enhance the safety of the dam and water reservoir, with a budget of 157 billion dong, completed in 2022 after detecting cracks. The company also proposed an investment of 1,500 billion dong for repair and upgrade from 2021 to 2025. During the second phase of repairs, the Southern Water Irrigation Company cut off water for 90 days to the West main canal with the approval of the Tay Ninh People's Committee, extending from April 5, 2023, and resumed water flow on January 10, 2024, to serve the new agricultural season.
In 2024, Prime Minister Phạm Minh Chính assigned Tây Ninh to leverage the functions provided by the Dau Tieng reservoir. Previously, the province was tasked with developing the comprehensive multi-objective project "Dau Tieng Development Master Plan Phase 2022–2030, Vision 2050," which was later cancelled due to exceeding the province's authority in various laws, sectors, and planning aspects.
Exploitation
Tourism
In 2008, the Tây Ninh Provincial People's Committee called for investment in tourism areas within the lake, including Nhim Island, Sin Islet, Tan Thiet Islet, Tan Hoa Islet, Ba Chiem Islet, Ta Do Islet, Dong Ken Islet, and along the southern shore of the lake. In 2022, the Bình Dương Provincial People's Committee held a meeting to hear the consulting unit's report on the Ecotourism, Resort, and Recreation Project for the Nui Cau – Dầu Tiếng Protective Forest for the period 2021 – 2030, envisioning it as a "miniature Đà Lạt."
In 2016, many residents discovered an impromptu beach area in the Dầu Tiếng Lake area. Shortly thereafter, local authorities requested that residents dismantle and move out of the lake area as it was unregulated, posing potential security and drowning risks. By the end of May of the same year, the Tây Ninh Provincial People's Committee assigned relevant units to invest in infrastructure and transform the area into a natural beach named "Tây Ninh Sea.".
In 2022, under the management of the Tây Ninh Provincial Department of Culture, Sports, and Tourism, the Paragliding and Kite Flying Sports Federation was established. The launch event and paragliding performance were held at the Dầu Tiếng Lake area in Dương Minh Châu District, Tây Ninh province, over two days, April 30 and May 1. As part of Tây Ninh province's urban development plan, Dương Minh Châu has been approved to become a tourism service development area surrounding Ba Den Mountain and Dầu Tiếng Lake.
Fisheries
According to a survey conducted by the Livestock and Veterinary Bureau under the Tây Ninh Department of Agriculture and Rural Development, Dầu Tiếng Lake is home to more than 50 fish species, including 10 economically valuable species such as featherback fish, catfish, snakehead fish, and anchovy. However, according to statistics from the Institute of Fisheries II under the Ministry of Agriculture and Rural Development, the lake hosts around 60 fish species and numerous other aquatic species, with 15 species providing economic value such as carp, climbing perch, mystus fish, and catfish. Species belonging to the carp family are reported to account for about 33.33%, catfish family 30%, goby family 23.33%, and various other fish species. Since its construction, the number of fish species in the lake has increased by 14 compared to the upstream Saigon River, with 33 new species appearing and 19 species disappearing. The vanished aquatic species include climbing perch, fire snakehead, gourami, barred mystus, herring, giant gourami, and notably, giant freshwater prawn. The appearance of many other fish species is attributed to local residents farming various economically valuable fish in cages and pens. From 2005 to 2013, 7.8 million fish were released into the lake by local authorities to replenish the aquatic resources.
According to the Tay Ninh newspaper, the province annually allocates a budget of 500–700 million VND to release tens of millions of fish fry into Dau Tieng Lake to replenish aquatic resources. However, local authorities report that many fishermen in the lake have been using prohibited fishing gear such as stacked cages, gillnets, electrofishing, and light-attracting devices, causing severe damage to the lake's ecosystem. On March 25, 2024, the Southern Irrigation Exploitation One Member Limited Liability Company established a "Plan for coordinated inspection of activities within the protection scope of Dau Tieng irrigation works", which includes inspecting fishing gear and cage fish farming around the lake to protect the ecosystem and aquatic resources.
Irrigation
The Dau Tieng – Phuoc Hoa irrigation system, under the management of the Southern Irrigation Exploitation One Member Limited Liability Company, serves to provide water, control floods, repel salinity, and improve the environment for the downstream areas of the Saigon and Vam Co Dong river basins. The reservoir is currently the direct source of water for production for 116,953 hectares in the provinces and cities of Tay Ninh (92,953 ha), Ho Chi Minh City (12,000 ha), and Long An (12,000 ha); it also provides irrigation for 93,954 hectares along the Saigon and Vam Co Dong rivers. In 2017, Dinh La Thang proposed restarting the pipeline project connecting Dau Tieng Lake to the water plant in Ho Chi Minh City by calling for socialized investment. In 2018, the Tay Ninh government commenced construction of a project to bring water from Dau Tieng Lake to the west of the Vam Co Dong River to supply water to communes in Chau Thanh and Ben Cau districts of Tay Ninh province with a total investment of 1,246 billion VND. The project includes a steel pipe crossing the river with a span of 30 meters and a static clearance height of about 6 meters.
During the 2024 heatwave in Vietnam, Long An province requested the Southern Irrigation Exploitation One Member Limited Liability Company to release water from Dau Tieng Lake into the Vam Co Dong River to push back saltwater intrusion after the province declared a level 4 drought and salinity disaster on April 17. The company agreed and committed to releasing 7 million cubic meters of water through the Vam Co Dong River to support Long An. However, the Department of Agriculture and Rural Development of Long An province later requested the reservoir to increase the discharge rate to further assist the province. Previously, the reservoir had also released water to prevent saltwater intrusion in the Saigon River and the Dong Nai river system.
Minerals
In 2010, the People's Committee of Tay Ninh province agreed with Binh Phuoc province in Official Letter No. 1968 to hand over the licensing of mineral exploitation in the 16 km upstream area of the Saigon River, which is co-managed by the two provinces, to the People's Committee of Binh Phuoc province. Upon handing it over to Binh Phuoc, Tay Ninh stated that it would only coordinate management when necessary. Two months after the official letter took effect, Binh Phuoc granted the sole license to Thai Thinh Private Enterprise for sand exploitation for a period of 10 years. However, in 2017, this license was transferred to Phu Tho Production and Trading One Member Limited Liability Company. Subsequently, residents of Tan Hoa, Tan Chau reported to Tay Ninh province about serious erosion on the Tay Ninh side. Upon inspection, Thai Thinh Company had caused 150 meters of erosion into Tan Hoa territory without deploying buoys or mining signs. According to Tay Ninh provincial authorities, due to the vast area of the lake and the absence of residents in many areas, detecting illegal mineral exploitation within the lake is extremely difficult.
Notes
References
Artificial lakes
Saigon River
Hydraulic structures
Lakes of Vietnam
Irrigation projects
1981 establishments in Vietnam | Dầu Tiếng Lake | [
"Engineering"
] | 3,366 | [
"Irrigation projects"
] |
77,270,791 | https://en.wikipedia.org/wiki/Alternative%20title%20%28publishing%29 | An alternative title or alternate title in book publishing refers to a title that is presented alongside the primary title. It often uses a semi-colon or the term "or" in book titles, typically seen in the form "Title: or, Subtitle." This was a practice that started in the 17th century, and was common in both English and American literature. During this period, many books aimed to appeal to a broader audience by using more descriptive subtitles.
As an example, Mary Shelley gave her most famous novel the title Frankenstein; or, The Modern Prometheus, where or, The Modern Prometheus is the alternative title, by which she references the Greek Titan as a hint of the novel's themes. More examples are On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life and Moby-Dick; or, The Whale. This is contrasted to a subtitle, which is a portion of the title itself. The subtitle is considered to add extra explanation for the title.
This convention started to decline in the 19th century as book titles became more concise and marketing strategies evolved.
References
Book design
Publishing
Names | Alternative title (publishing) | [
"Engineering"
] | 243 | [
"Book design",
"Design"
] |
77,272,181 | https://en.wikipedia.org/wiki/IC%20361 | IC 361, also called Melotte 24 is an open cluster of stars in the constellation Camelopardalis. It was discovered by the British amateur astronomer William F. Denning on February 11, 1893. This cluster is located at a distance of from the Sun. It is very faint with an apparent visual magnitude of 11.7, requiring a telescope to view. Because of its faintness, this cluster has been poorly studied. The cluster spans an angular size of .
This intermediate–age cluster is located in or beyond the Perseus Arm of the Milky Way galaxy. It is situated near dark nebulae, resulting in significant levels of extinction due to interstellar dust. The cluster has a core radius of and a cluster radius of . At an estimated distance of this corresponds to a physical core radius of and a cluster radius of . It has an estimated age of 759 million years. The cluster is mildly metal deficient, matching the metallicity gradient of the Milky Way.
Two candidate blue stragglers have been identified in this cluster.
References
Further reading
Open clusters
Camelopardalis
0361 | IC 361 | [
"Astronomy"
] | 224 | [
"Camelopardalis",
"Constellations"
] |
77,272,538 | https://en.wikipedia.org/wiki/95%20Herculis | 95 Herculis is a double stellar system in the constellation Hercules, located 432 light-years from Earth.
Characteristics
From the naked eye, 95 Herculis appears as a single star shining at apparent magnitude 4.31. However, when further scrutinized using a telescope, it is revealed to be a double star, with two components separated by 6.3 arcseconds. This system has a color contrast due to the difference of each star's effective temperature.
The brightest component, called 95 Herculis A, is a white giant or subgiant with an apparent magnitude of 4.8. This evolved star has 2.9 times more mass than the Sun, is 6.8 times wider, and is 167 times more luminous. Its effective temperature of 8,000 Kelvin give it a blue-white hue typical of A-type stars. It is spinning rapidly with an projected rotational velocity of 233 km/s.
The secondary is called 95 Herculis B, a yellow giant of apparent magnitude 5.1. It is the most evolved star in the pair, having reached helium burning stage and now converting carbon into oxygen, while 95 Herculis A is still in the transition from hydrogen burning to helium burning. Albeit fainter than 95 Her A, 95 Her B emmits a significant part of its luminosity in the infrared, and hence the bolometric luminosity is 194 times solar. It is 3.2 times more massive than the Sun and 19 times wider. The effective temperature of the star is 4,900 Kelvin.
Orbit
The orbital elements 95 Herculis are not accurately known and no orbital motion has been detected. However, they projected separation is calculated at 900 astronomical units, with an orbital period of at least 11,000 years.
See also
Albireo
Gamma Andromedae
Gamma Leonis
References
Binary stars
Hercules (constellation)
A-type subgiants
G-type giants
Bright Star Catalogue objects
Henry Draper Catalogue objects
Hipparcos objects
TIC objects
Flamsteed objects | 95 Herculis | [
"Astronomy"
] | 416 | [
"Hercules (constellation)",
"Constellations"
] |
69,733,418 | https://en.wikipedia.org/wiki/Camelopardalis%20OB1 | Camelopardalis OB1 (Cam OB1) is a group of young stars that share a common origin and a similar motion through space, but, as a whole, are no longer gravitationally bound. The name indicates this stellar association is located in the area of the Camelopardalis constellation which includes a number of massive, short-lived OB stars. The association is ~ distant from the Sun, with members lying between and away. It is located on the edge of the local Orion Arm of the Milky Way galaxy and lies outside the traditional Gould Belt.
The member stars were first classified as an association by Georg (Jiří) Alter, B. Y. Israel, and Jaroslav Ruprecht in 1966. The open cluster NGC 1502 is considered a member of Cam OB1. A second cluster in Cam OB1, G144.9+0.4, was identified in 2010 with 91 OB candidate stars. Excluding these clusters, two O-type and 35 B-type stars have been identified as members. Stars have been forming in the region of this association for the last 100 million years, and star formation is still in progress. It has a combined mass of ~5,000 times the mass of the Sun.
References
Stellar associations
Camelopardalis | Camelopardalis OB1 | [
"Astronomy"
] | 259 | [
"Camelopardalis",
"Constellations"
] |
69,734,350 | https://en.wikipedia.org/wiki/%28Trimethylsilyl%29methyl%20chloride | (Trimethylsilyl)methyl chloride is the organosilicon compound with the formula (CH3)3SiCH2Cl. A colorless, volatile liquid, it is an alkylating agent that is employed in organic synthesis, especially as a precursor to (trimethylsilyl)methyllithium. In the presence of triphenylphosphine, it olefinates benzophenones:
See also
Trimethylsilyl chloride, a silyl chloride
References
Trimethylsilyl compounds
Organochlorides | (Trimethylsilyl)methyl chloride | [
"Chemistry"
] | 114 | [
"Functional groups",
"Trimethylsilyl compounds"
] |
69,735,469 | https://en.wikipedia.org/wiki/Chentsov%27s%20theorem | In information geometry, Chentsov's theorem states that the Fisher information metric is, up to rescaling, the unique Riemannian metric on a statistical manifold that is invariant under sufficient statistics.
The theorem is named after its inventor Nikolai Chentsov
See also
Fisher information
Sufficient statistic
Information geometry
References
N. N. Čencov (1981), Statistical Decision Rules and Optimal Inference, Translations of mathematical monographs; v. 53, American Mathematical Society, http://www.ams.org/books/mmono/053/
Shun'ichi Amari, Hiroshi Nagaoka (2000) Methods of information geometry, Translations of mathematical monographs; v. 191, American Mathematical Society, http://www.ams.org/books/mmono/191/ (Theorem 2.6)
Differential geometry
Information geometry
Statistical distance | Chentsov's theorem | [
"Physics",
"Mathematics"
] | 178 | [
"Mathematical structures",
"Physical quantities",
"Statistical distance",
"Distance",
"Category theory",
"Information geometry"
] |
69,736,905 | https://en.wikipedia.org/wiki/Modern%20triangle%20geometry | In mathematics, modern triangle geometry, or new triangle geometry, is the body of knowledge relating to the properties of a triangle discovered and developed roughly since the beginning of the last quarter of the nineteenth century. Triangles and their properties were the subject of investigation since at least the time of Euclid. In fact, Euclid's Elements contains description of the four special points – centroid, incenter, circumcenter and orthocenter - associated with a triangle. Even though Pascal and Ceva in the seventeenth century, Euler in the eighteenth century and Feuerbach in the nineteenth century and many other mathematicians had made important discoveries regarding the properties of the triangle, it was the publication in 1873 of a paper by Emile Lemoine (1840–1912) with the title "On a remarkable point of the triangle" that was considered to have, according to Nathan Altschiller-Court, "laid the foundations...of the modern geometry of the triangle as a whole." The American Mathematical Monthly, in which much of Lemoine's work is published, declared that "To none of these [geometers] more than Émile-Michel-Hyacinthe Lemoine is due the honor of starting this movement of modern triangle geometry". The publication of this paper caused a remarkable upsurge of interest in investigating the properties of the triangle during the last quarter of the nineteenth century and the early years of the twentieth century. A hundred-page article on triangle geometry in Klein's Encyclopedia of Mathematical Sciences published in 1914 bears witness to this upsurge of interest in triangle geometry.
In the early days, the expression "new triangle geometry" referred to only the set of interesting objects associated with a triangle like the Lemoine point, Lemoine circle, Brocard circle and the Lemoine line. Later the theory of correspondences which was an offshoot of the theory of geometric transformations was developed to give coherence to the various isolated results. With its development, the expression "new triangle geometry" indicated not only the many remarkable objects associated with a triangle but also the methods used to study and classify these objects. Here is a definition of triangle geometry from 1887: "Being given a point M in the plane of the triangle, we can always find, in an infinity of manners, a second point M' that corresponds to the first one according to an imagined geometrical law; these two points have between them geometrical relations whose simplicity depends on the more or less the lucky choice of the law which unites them and each geometrical law gives rise to a method of transformation a mode of conjugation which it remains to study." (See the conference paper titled "Teaching new geometrical methods with an ancient figure in the nineteenth and twentieth centuries: the new triangle geometry in textbooks in Europe and USA (1888–1952)" by Pauline Romera-Lebret presented in 2009.)
However, this escalation of interest soon collapsed and triangle geometry was completely neglected until the closing years of the twentieth century. In his "Development of Mathematics", Eric Temple Bell offers his judgement on the status of modern triangle geometry in 1940 thus: "The geometers of the 20th Century have long since piously removed all these treasures to the museum of geometry where the dust of history quickly dimmed their luster." (The Development of Mathematics, p. 323) Philip Davis has suggested several reasons for the decline of interest in triangle geometry. These include:
The feeling that the subject is elementary and of low professional status.
The exhaustion of its methodologic possibilities.
The visual complexity of the so-called deeper results of the subject.
The downgrading of the visual in favor of the algebraic.
A dearth of connections to other fields.
Competition with other topics with a strong visual content like tessellations, fractals, graph theory, etc.
A further revival of interest was witnessed with the advent of the modern electronic computer. The triangle geometry has again become an active area of research pursued by a group of dedicated geometers. As epitomizing this revival, one can point out the formulation of the concept of a "triangle centre" and the compilation by Clark Kimberling of an encyclopedia of triangle centers containing a listing of nearly 50,000 triangle centers and their properties and also the compilation of a catalogue of triangle cubics with detailed descriptions of several properties of more than 1200 triangle cubics. The open access journal Forum Geometricorum founded by Paul Yiu of Florida Atlantic University in 2001 also provided a tremendous impetus in furthering this new found enthusiasm for triangle geometry. Unfortunately, since 2019, the journal is not accepting submissions although back issues are still available online.
The Lemoine geometry
Lemoine point
For a given triangle ABC with centroid G, the symmedian through the vertex is the reflection of the line AG in the bisector of the angle A. There are three symmedians for a triangle one passing through each vertex. The three symmedians are concurrent and the point of concurrency, commonly denoted by K, is called the Lemoine point or the symmedian point or the Grebe point of triangle ABC. If the sidelengths of triangle ABC are a, b, c the baricentric coordinates of the Lemoine point are a2 : b2 : c2. It has been described as "one of the crown jewels of modern geometry". There are several earlier references to this point in the mathematical literature details of which are available in John Mackay' history of the symmedian point.
In fact, the concurrency of the symmedians is a special case of a more general result: For any point P in the plane of triangle ABC, the isogonals of the lines AP, BP, CP are concurrent, the isogonal of AP (respectively BP, CP) being the reflection of the line AP in the bisector of the angle A (respectively B, C). The point of concurrency is called the isogonal conjugate of P. In this terminology, the Lemoine point is the isogonal conjugate of the centroid.
Lemoine circles
The points of intersections of the lines through the Lemoine point of a triangle ABC parallel to the sides of the triangle lie on a circle called the first Lemoine circle of triangle ABC. The center of the first Lemoine circle lies midway between the circumcenter and the lemoine point of the triangle,
The points of intersections of the antiparallels to the sides of triangle ABC through the Lemoine point of a triangle ABC lie on a circle called the second Lemoine circle or the cosine circle of triangle ABC. The name "cosine circle" is due to the property of the second Lemoine circle that the lengths of the segments intercepted by the circle on the sides of the triangle proportional to the cosines of the angles opposite to the sides. The center of the second Lemoine circle is the Lemoine point.
Lemoine axis
Any triangle ABC and its tangential triangle are in perspective and the axis of perspectivity is called the Lemoine axis of triangle ABC. It is the trilinear polar of the symmedian point of triangle ABC and also the polar of K with regard to the circumcircle of triangle ABC.
Early modern triangle geometry
A quick glance into the world of modern triangle geometry as it existed during the peak of interest in triangle geometry subsequent to the publication of Lemoine's paper is presented below. This presentation is largely based on the topics discussed in William Gallatly's book published in 1910 and Roger A Johnsons' book first published in 1929.
Poristic triangles
Two triangles are said to be poristic triangles if they have the same incircle and circumcircle. Given a circle with Center O and radius R and another circle with center I and radius r, there are an infinite number of triangles ABC with Circle O(R) as circumcircle and I(r) as incircle if and only if OI2 = R2 − 2Rr . These triangles form a poristic system of triangles. The loci of certain special points like the centroid as the reference triangle traces the different triangles poristic with it turn out to often be circles and points.
The Simson line
For any point P on the circumcircle of triangle ABC, the feet of perpendiculars from P to the sides of triangle ABC are collinear and the line of collinearity is the well-known Simson line of P.
Pedal and antipedal triangles
Given a point P, let the feet of perpendiculars from P to the sides of the triangle ABC be D, E, F. The triangle DEF is called the pedal triangle of P. The antipedal triangle of P is the triangle formed by the lines through A, B, C perpendicular to PA, PB, PC respectively. Two points P and Q are called counter points if the pedal triangle of P is homothetic to the antipedal triangle of Q and the pedal triangle of Q is homothetic to the antipedal triangle of P.
The orthopole
Given any line l, let P, Q, R be the feet of perpendiculars from the vertices A, B, C of triangle ABC to l. The lines through P. Q, R perpendicular respectively to the sides BC, CA, AB are concurrent and the point of concurrence is the orthopole of the line l with respect to the triangle ABC. In modern triangle geometry, there is a large body of literature dealing with properties of orthopoles.
The Brocard points
Let of circles be described on the sides BC, CA, AB of triangle ABC whose external segments contain the two triads of angles C, A, B and B, C, A respectively. Each triad of circles determined by a triad of angles intersect at a common point thus yielding two such points. These points are called the Brocard points of triangle ABC and are usually denoted by . If P is the first Brocard point (which is the Brocard point determined by the first triad of circles) then the angles PBC, PCA and PAB are equal to each other and the common angle is called the Brocard angle of triangle ABC and is commonly denoted by The Brocard angle is given by
The Brocard points and the Brocard angles have several interesting properties.
Some images
Contemporary modern triangle geometry
Triangle center
One of the most significant ideas that has emerged during the revival of interest in triangle geometry during the closing years of twentieth century is the notion of triangle center. This concept introduced by Clark Kimberling in 1994 unified in one notion the very many special and remarkable points associated with a triangle. Since the introduction of this idea, nearly no discussion on any result associated with a triangle is complete without a discussion on how the result connects with the triangle centers.
Definition of triangle center
A real-valued function f of three real variables a, b, c may have the following properties:
Homogeneity: f(ta,tb,tc) = tn f(a,b,c) for some constant n and for all t > 0.
Bisymmetry in the second and third variables: f(a,b,c) = f(a,c,b).
If a non-zero f has both these properties it is called a triangle center function. If f is a triangle center function and a, b, c are the side-lengths of a reference triangle then the point whose trilinear coordinates are f(a,b,c) : f(b,c,a) : f(c,a,b) is called a triangle center.
Clark Kimberling is maintaining a website devoted to a compendium of triangle centers. The website named Encyclopedia of Triangle Centers has definitions and descriptions of nearly 50,000 triangle centers.
Central line
Another unifying notion of contemporary modern triangle geometry is that of a central line. This concept unifies the several special straight lines associated with a triangle. The notion of a central line is also related to the notion of a triangle center.
Definition of central line
Let ABC be a plane triangle and let ( x : y : z ) be the trilinear coordinates of an arbitrary point in the plane of triangle ABC.
A straight line in the plane of triangle ABC whose equation in trilinear coordinates has the form
f ( a, b, c ) x + g ( a, b, c ) y + h ( a, b, c ) z = 0
where the point with trilinear coordinates ( f ( a, b, c ) : g ( a, b, c ) : h ( a, b, c ) ) is a triangle center,
is a central line in the plane of triangle ABC relative to the triangle ABC.
Geometrical construction of central line
Let X be any triangle center of the triangle ABC.
Draw the lines AX, BX and CX and their reflections in the internal bisectors of the angles at the vertices A, B, C respectively.
The reflected lines are concurrent and the point of concurrence is the isogonal conjugate Y of X.
Let the cevians AY, BY, CY meet the opposite sidelines of triangle ABC at A' , B' , C' respectively. The triangle A'B'C' is the cevian triangle of Y.
The triangle ABC and the cevian triangle A'B'C' are in perspective and let DEF be the axis of perspectivity of the two triangles. The line DEF is the trilinear polar of the point Y. The line DEF is the central line associated with the triangle center X.
Triangle conics
A triangle conic is a conic in the plane of the reference triangle and associated with it in some way. For example, the circumcircle and the incircle of the reference triangle are triangle conics. Other examples are the Steiner ellipse which is an ellipse passing through the vertices and having its centre at the centroid of the reference triangle, the Kiepert hyperbola which is a conic passing through the vertices, the centroid and the orthocentre of the reference triangle and the Artzt parabolas which are parabolas touching two sidelines of the reference triangle at vertices of the triangle. Some recently studied triangle conics include Hofstadter ellipses and yff conics. However, there is no formal definition of the terminology of triangle conic in the literature; that is, the relations a conic should have with the reference triangle so as to qualify it to be called a triangle conic have not been precisely formulated. WolframMathWorld has a page titled "Triangle conics" which gives a list of 42 items (not all of them are conics) without giving a definition of triangle conic.
Triangle cubics
Cubic curves arise naturally in the study of triangles. For example, the locus of a point P in the plane of the reference triangle ABC such that, if the reflections of P in the sidelines of triangle ABC are Pa, Pb, Pc, then the lines APa, BPb and CPc are concurrent is a cubic curve named Neuberg cubic. It is the first cubic listed in Bernard Gibert's Catalogue of Triangle Cubics. This Catalogue lists more than 1200 triangle cubics with information on each curve such as the barycentric equation of the curve, triangle centers which lie on the curve, locus properties of the curve and references to literature on the curve.
Computers in triangle geometry
The entry of computers had a deciding influence on the course of development in the interest in triangle geometry witnessed during the closing years of the twentieth century and the early years of the current century. Some of the ways in which the computers had influenced this course have been delineated by Philip Davis. Computers have been used to generate new results in triangle geometry. A survey article published in 2015 gives an account of some of the important new results discovered by the computer programme "Discoverer". The following sample of theorems gives a flavor of the new results discovered by Discoverer.
Theorem 6.1 Let P and Q are points, neither lying on a sideline of triangle ABC. If P and Q are isogonal conjugates with respect to ABC, then the Ceva product of their complements lies on the Kiepert hyperbola.
Theorem 9.1. The Yff center of congruence is the internal center of similitude of the incircle and the circumcircle with respect to the pedal triangle of the incenter.
The Lester circle is the circle which passes through the circumcenter, the nine-point center and the outer and inner Fermat points. A generalised Lester circle is a circle which passes through at least four triangle centers. Discoverer has discovered several generalized Lester circles.
Sava Grozdev, Hiroshi Okumura, Deko Dekov are maintaining a web portal dedicated to computer discovered encyclopedia of Euclidean geometry.
References
Additional reading
Triangle geometry
History of geometry | Modern triangle geometry | [
"Mathematics"
] | 3,515 | [
"History of geometry",
"Geometry"
] |
69,736,916 | https://en.wikipedia.org/wiki/Architecture%20of%20Tunisia | The architecture of Tunisia began with the ancient civilizations such as the Carthaginians, Numidians, and Romans. After the 7th century, Islamic architecture developed in the region under a succession of dynasties and empires. In the late 19th century French colonial rule introduced European architecture, and modern architecture became common in the second half of the 20th century. The southern regions of the country are also home to diverse examples of local vernacular architecture used by the Berber (Amazigh) population.
Antiquity
Punic Carthage
Large regions of North Africa, particularly near the coasts, came under the control of Carthage, a Phoenician civilization, at the height of its power in the third century BC. The remains of Carthage are found near Tunis today and contain the remains of multiple periods ranging from the Punic period to the later Arab occupation. Vestiges of the Punic period include the "Punic Ports" (the city's ancient harbors) and a sanctuary and necropolis dedicated to Baal Hammon, known today as the Sanctuary of Tophet.
Numidia
The kingdom of Numidia was contemporary with the Carthaginian civilization and the Roman Republic. Among other things, the Numidians have left thousands of pre-Christian tombs. The oldest of these is Medracen in present-day Algeria, believed to date from the time of Masinissa (202–148 BC), which consists of a tumulus structure in ashlar masonry. Elsewhere, a number of "tower tombs" from the Numidian period can also be found in sites from Algeria to Libya. Despite their wide geographic range, they often share a similar style: a three-story structure topped by a convex pyramid. They may have initially been inspired by Greek monuments but they constitute an original type of structure associated with Numidian culture. An important example in present-day Tunisia is the Libyco-Punic Mausoleum at the site of Dougga.
Roman and Byzantine period
After defeating Carthage, Rome progressively took over the entire coast of North Africa from Egypt to the Atlantic coast of modern-day Morocco. Most of present-day Tunisia was occupied by the Roman province known as Africa. Significant remains of Roman architecture can be found in Tunisia today, including Roman Carthage, the amphitheater of El Jem, the site of Dougga (Thugga), the temples of Sbeitla (Sufetula), and others. After the fall of the Western Roman Empire, the Eastern Roman or Byzantine Empire continued to rule parts of the region up until the 7th century.
Early Islamic period
In the 7th century the region of North Africa became steadily integrated into the emerging Muslim world during the Early Arab-Muslim Conquests. The territory of Ifriqiya (roughly present-day Tunisia), and its newly founded capital city of Kairouan (also transliterated as "Qayrawan") became an early center of Islamic culture for the region. The Great Mosque of Kairouan was founded here by Uqba ibn Nafi in 670, though it was rebuilt under the Aghlabids. Islamic architecture continued to develop in the region afterwards.
Aghlabids
In the 9th century the province of Ifriqiya, while still nominally under the control of the Abbasid Caliphs in Baghdad, was de facto ruled by the Aghlabid dynasty. The Aghlabids were major builders and erected many of Tunisia's oldest Islamic-era monuments, including military structures like the Ribat of Sousse and the Ribat of Monastir, religious buildings like the Great Mosque of Sousse and the Great Mosque of Sfax, and practical infrastructure works like the Aghlabid Reservoirs of Kairouan. The al-Zaytuna Mosque in Tunis, which was founded earlier around 698, owes its overall current form to the Aghlabid emir Abu Ibrahim Ahmad (r. 856–863). Much of Aghlabid architecture, even their mosques, had a heavy and almost fortress-like appearance, but they nonetheless left an influential artistic legacy. For example, the Mosque of Ibn Khayrun (also known as the "Mosque of the Three Doors") possesses what is considered by some to be the oldest decorated external façade in Islamic architecture, featuring carved Kufic inscriptions and vegetal motifs.
One of the most important Aghlabid monuments is the Great Mosque of Kairouan, which was completely rebuilt by the emir Abu Muhammad Ziyadat Allah (r. 817–838) in 836, although various additions and repairs were effected later which complicate the chronology of its construction. The mosque features an enormous rectangular courtyard, a large hypostyle prayer hall, and a thick three-story minaret (tower from which the call to prayer was issued). The mihrab (niche symbolizing the direction of prayer) of the prayer hall is among the oldest examples of its kind, richly decorated with marble panels carved in high-relief vegetal motifs and with ceramic tiles with overglaze and luster. Next to the mihrab is the oldest surviving minbar (pulpit) in the world, made of richly-carved teakwood panels. Both the carved panels of the minbar and the ceramic tiles of the mihrab are believed to be imports from Abbasid Iraq. An elegant dome in front of the mihrab with an elaborately-decorated drum is one of architectural highlights of this period.
Fatimids
In Ifriqiya, the Fatimids also built extensively, most notably with the creation of a new fortified capital on the coast, Mahdia. Construction began in 916 and the new city was officially inaugurated on February 20, 921, although some construction continued. In addition to its heavy fortified walls, the city included the Fatimid palaces, an artificial harbor, and the Great Mosque of Mahdia. Much of this has not survived to the present day. Fragments of mosaic pavements from the palaces have been discovered from modern excavations. The mosque is one of the most well-preserved Fatimid monuments in the Maghreb, although it too has been extensively damaged over time and was in large part reconstructed by archeologists in the 1960s. It consists of a hypostyle prayer hall with a roughly square courtyard. The mosque's original main entrance, a monumental portal projecting from the wall, was relatively unusual at the time and may have been inspired by ancient Roman triumphal arches. Another unusual feature was the absence of a minaret, which may have reflected an early Fatimid rejection of such structures as unnecessary innovations.
Islamic Berber dynasties
Zirids
After the Fatimids moved their base of power to Cairo, Egypt, in the 10th century, new Berber dynasties such as the Zirids ruled nominally on their behalf. As independent rulers, however, the Zirids of Ifriqiya built relatively few grand structures. They reportedly built a new palace at al-Mansuriyya, a former Fatimid capital near Kairouan, but it has not been found by modern archeologists. In Kairouan itself the Great Mosque was restored by Al-Mu'izz ibn Badis. The wooden maqsura within the mosque today is believed to date from this time. It is the oldest maqsura in the Islamic world to be preserved in situ and was commissioned by al-Mu῾izz ibn Badis in the first half of the 11th century (though later restored). It is notable for its woodwork, which includes an elaborately carved Kufic inscription dedicated to al-Mu'izz. The Qubbat al-Bahw, an elegant dome at the entrance of the prayer hall of the al-Zaytuna Mosque in Tunis, dates from 991 and can be attributed to Al-Mansur ibn Buluggin.
Hafsids (and Almohads)
The patronage of the Almohads – as well as of the Almoravids who preceded them in the western Maghreb – is considered one of the most formative stages of "Moorish" (western Islamic) architecture, establishing many of the forms and motifs that defined architectural styles in the region during the subsequent centuries. Ifriqiya was far from the main Almohad capital at Marrakesh (present-day Morocco) and the Almohads themselves did not leave significant monuments here. However, they made Tunis the regional capital of their territories in Ifriqiya and established the city's kasbah (citadel) as their center of government.
The Hafsids, a branch of the Almohad ruling class, declared their independence from the Almohads in 1229 and developed their own state which came to control much of Ifriqiya and some of the surrounding region. They were also significant builders, particularly under the reigns of successful leaders like Abu Zakariya (ruled 1229–1249) and Abu Faris (ruled 1394–1434), though not many of their monuments have survived intact to the present-day. While Kairouan remained an important religious center, Tunis was the capital and progressively replaced it as the main city of the region and the main center of architectural patronage. Unlike the architecture further west, Hafsid architecture was built primarily in stone (rather than brick or mudbrick) and appears to have featured much less decoration. In reviewing the history of architecture in the region, scholar Jonathan Bloom remarks that Hafsid architecture seems to have "largely charted a course independent of the developments elsewhere in the Maghrib [North Africa]".
The Kasbah Mosque of Tunis was one of the first works of this period, built by Abu Zakariya (the first independent Hafsid ruler) at the beginning of his reign. Its floor plan had noticeable differences from previous Almohad-period mosques but the minaret, completed in 1233, bears very strong resemblance the minaret of the earlier Almohad Kasbah Mosque in Marrakesh. This Hafsid minaret influenced the design of later Tunisian minarets. Other foundations from the Hafsid period in Tunis include the Haliq Mosque (13th century) and the al-Hawa Mosque (1375), and the Bab al-Aqwas Mosque (15th century). The Hafsids also made significant renovations to the much older Great Mosque of Kairouan – renovating its ceiling, reinforcing its walls, and building or rebuilding two of its entrance gates in 1293 – as well as to the al-Zaytuna Mosque in Tunis. The Bardo Palace (today a national museum) was also begun by the Hafsids in the 15th century, and is mentioned in historical records for the first time during the reign of Abu Faris.
The Hafsids also introduced the first madrasas to the region, beginning with the Madrasa al-Shamma῾iyya built in Tunis in 1238 (or in 1249 according to some sources). This was followed by many others (almost all of them in Tunis) such as the Madrasa al-Hawa founded in the 1250s, the Madrasa al-Ma'ridiya (1282), and the Madrasa al-Unqiya (1341). Many of these early madrasas, however, have been poorly preserved or have been considerably modified in the centuries since their foundation. The Madrasa al-Muntasiriya, completed in 1437, is among the best preserved madrasas of the Hafsid period.
The Mausoleum of Sidi Qasim al-Jalizi, in the suburbs west of Tunis, was built towards the end of the 15th century (), founded by Sidi Qasim al-Jalizi (d. 1496), a zellij craftsman of Andalusi origin who was buried here at his death. While expanded in later centuries, the main mausoleum chamber still dates to the Hafsid period and displays a fusion of styles that is characteristic of the period. Rather than covered by a traditional vault or spherical dome, the chamber is covered by a pyramidal wooden roof with green tiles on the outside, typical of contemporary buildings further west in Morocco and al-Andalus. The hall's interior is decorated with several elements also characteristic of architecture further west, including carved stucco on the upper walls, flowery capitals, and cuerda seca tiles on the mihrab niche and lower walls that appear to be a local interpretation of the Hispano-Moresque style. On the other hand, the hall also features marble decoration on walls, columns, and around the framing of arches, which appear to be influenced by Ayyubid and Mamluk architecture further east.
Ottoman period
Over the course of the 16th century the central and eastern Maghreb – Algeria, Tunisia, and Libya – came under Ottoman control. Major port cities such as Algiers, Tunis, and Tripoli also became centers of pirate activity, which brought in wealth to local elites but also attracted intrusions by European powers, who occupied and fortified some coastal positions. After 1591, local power in Tunisia was effectively seized by the Janissaries, who appointed a Dey to lead them. In In the late 17th century and early 18th century, Ottoman control became largely nominal and Tunisia was ruled in practice by the Beys, who were drawn from the Muradid dynasty until 1702 and from the Husaynid dynasty after 1705. Architecture in Tunisia came under the influence of Ottoman architecture, especially in the coastal cities where Ottoman influence was strongest. Some European influences were also introduced, particularly through the importation of materials from Italy such as marble.
Religious and funerary architecture
In Tunis, the Mosque complex of Yusuf Dey, built or begun around 1614–15 by Yusuf Dey (r. 1610–1637), is one of the earliest and most important examples that imported Ottoman elements into local architecture. Its congregational mosque is accompanied by a madrasa, a primary school, fountains, latrines, and even a café (still functioning today), many of which provided revenues for the upkeep of the complex. This arrangement is similar to Ottoman külliye complexes. It was also the first example of a "funerary mosque" in Tunis, as the complex includes the founder's mausoleum, dated to 1639. While the hypostyle form of the mosque and the pyramidal roof of the mausoleum reflect traditional architecture in the region, the minaret's octagonal shaft reflects the influence of the "pencil"-shaped Ottoman minarets. Instead of the traditional square courtyard, a roughly U-shaped open space wraps around the mosque and a columned portico precedes its entrance. In this period, octagonal minarets often distinguished mosques following the Hanafi maddhab (which was associated with the Ottomans), while mosques which continued to follow the Maliki maddhab (predominant in the Maghreb) continued to employ traditional square-shaft minarets.
The Muradids built and restored many monuments and structures throughout the country during the 17th century, aided by a flourishing economy. The Mosque of Hammuda Pasha, built by Hammuda Pasha (r. 1631–1664) between 1631 and 1654, reprises many of these same elements as the Yusuf Dey Mosque. Both the Hammuda Pasha Mosque and, to a lesser extent, the Yusuf Dey Mosque make use of marble columns and capitals that were imported from Italy and possibly even carved by Italian craftsmen in Tunis. Hammuda Pasha was also responsible for starting in 1629 a major restoration and expansion of the Zawiya of Abu al-Balawi or "Mosque of the Barber" in Kairouan. While the Zawiya has been further modified since, one of its characteristic 17th-century features is the decoration of underglaze-painted Qallalin tiles on many of its walls. These tiles, generally produced in the Qallalin district of Tunis, are painted with motifs of vases, plants, and arches and use predominant blue, green, and ochre-like yellow colours which distinguish them from contemporary Ottoman tiles. The artistic height of these tiles was in the 17th and 18th centuries.
In Testour, the Great Mosque there was begun in 1615 and constitutes one of the most important examples of mosque architecture influenced by Andalusian morisco immigrants who fled Spain in this period. Its three-tiered minaret has a lower square shaft while its two upper tiers have octagonal shafts decorated with marble paneling, tiles, and – unusually – a 24-hour clock. Elements of the minaret and the mosque appear to be inspired by the architectural styles and construction methods of Aragon and Castile, where the moriscos originated. The minaret of the al-Qsar Mosque in Tunis, added in 1647 by Muhammad Laz Dey (r. 1647–1653) to the much older mosque, also combines a diversity of styles.
It wasn't until the end of the 17th century that the first Ottoman-style domed mosque was built. Muhammad Bey constructed the Sidi Mahrez Mosque – dedicated to Abu Muhammad Mahraz, d. 1022, who was buried here – which was completed by his successor, Ramadan ibn Murad, between 1696 and 1699. The mosque's prayer hall is covered by a dome system typical of Classical Ottoman architecture and first employed by Sinan for the Şehzade Mosque (c. 1548) in Istanbul: a large central dome flanked by four semi-domes, with four smaller domes at the corners and pendentives in the transitional zones between the semi-domes. The interior is decorated with marble paneling and Ottoman Iznik tiles. This was the only mosque in Tunisia designed in such a strongly Ottoman style and the last major foundation built under the Muradids.
Under Husayn ibn Ali (r. 1705–1735), founder of the Husaynid dynasty, the Zawiya (mausoleum complex) of Sidi Qasim al-Jalizi, was restored and expanded. A decorated courtyard had previously been added to the mausoleum in the 17th century, and Husayn added to the complex a nine-bay prayer hall.
Husayn's successor, 'Ali Pasha (r. 1740–1765), built four madrasas, more than any other previous ruler in Tunisia. The madrasas he built are distinguished by their rich decoration of marble paneling, carved stucco, and Qallalin tiles. Two of them, the Madrasa al-Bashiya (1752) and the Madrasa as-Slimaniyya (1754), are located behind the Zaytuna Mosque, near his mausoleum.
Most of the Husaynid beys, along with many of their family members and close associates, were buried in a mausoleum known as Turbet el-Bey, which includes decorative details in an Italianate style. One of the last and most impressive Husaynid-era mosques is the Mosque of Yusuf Sahib al-Taba' (one of Hamuda's ministers) in Tunis, built between 1808 and 1814. It is similar again to the Yusuf Dey Mosque, with decoration mixing both local and European influences.
Palace and domestic architecture
A notable example of domestic architecture from the early Ottoman period is Dar Othman, a palace built by 'Uthman Dey between 1594 and 1611, with later expansions and restorations. It is notable for the decoration of its entrance, which is faced with black and white marble, recalling 15th-century Hafsid decoration. It has an internal courtyard flanked on two sides by an arcade of horseshoe arches with alternating black and white stone, though this section may date from a later period. Italian and Ottoman/Turkish influences are evident in some of the details and decorative motifs.
Husayn ibn Ali transformed the Bardo Palace into a massive fortified complex with various amenities including a mosque, a madrasa, a hammam and a market. Later beys added further apartments and residences to it. One of these additions, the Dar al-Harim, is a reception hall with a cross-shaped layout and a central dome, something typical of Ottoman palace architecture. The complex continued to be modified up to the 21st century, now housing a national museum and the National Assembly.
Various other palaces were also built in Tunis and the surrounding areas in the Husaynid period. 'Ali's son, Hammuda, built another palace, the Dar al-Bey, near the Kasbah of the city, and another one called the Manuba (or Mannouba) Palace. A summerhouse from the latter was relocated in the 19th century to the present-day Belvedere Park in Tunis. Other examples of private mansions built in the old city of Tunis during this period include Dar Hussein, built in the 18th century and expanded and decorated again in the early 19th century, the Dar Ben Abdallah, dated to 1796, and Dar Lasram, built in the early 19th century.
Traditional Tunisian houses of this era, like those of preceding periods, were centered around a square or rectangular interior courtyard, around which most rooms were arranged. Arcaded galleries usually ran along each side of the courtyard, or sometimes on two sides facing each other. The largest rooms were transversal rectangular halls connected to the courtyards, or T-shaped halls with a part of the room projecting outwards at the middle back of the hall. Few windows opened to the outside, with most of the light being provided by the courtyard, and most embellishments were concentrated on the inside.
Colonial period to present day
French colonial rule
France invaded Tunisia in 1881, imposing the French Protectorate which lasted until 1956. Unlike Algiers, where the French demolished much of the old city after 1830 to build their own colonial edifices, in Tunis the French built their new planned city outside the existing historic walled city. The old city became known as the medina (from the Arabic word for "city") while the new city became known as the Ville Nouvelle (French for "New City"). The new European-built districts across the country were built in contemporary French and European architectural styles, but in many cases architects also constructed buildings in what they considered to be the "Arab" style. The latter style ranged from extravagant pastiches of Moorish/Islamic architecture to more academic designs resulting from study of the country's indigenous architecture. This "Arabizing" (arabisant) architecture (similar to Neo-Moorish) could be seen in many official buildings such as railway stations, post offices, and law courts, as well as in some private villas. One lavish example is the villa designed by Italian millionaire Georges Sebastian in 1939–40 near Hammamet.
Independence and present day
After the country's independence, and particularly from the 1970s onward, modern architecture predominated for the construction of new blocs of flats, office towers, and hotels. Some architects, such as Tarak ben Miled and Serge Santelli, nonetheless attempted to develop a style that combined ideas from both modern and traditional Tunisian architecture. Many Tunisians also left houses in the medinas to live in modern houses in the new cities that the Europeans had left. Conservation efforts, sometimes aided by UNESCO, began to be put in place to help preserve the historic fabric of historic cities.
Other local architectural styles
Southern Tunisia
Southern Tunisia, which has a more predominantly Berber (Amazigh) population is dotted with hilltop ksour (fortified villages) and multi-story fortified granaries (ghorfa), such as the examples in Medenine and Ksar Ouled Soltane, which are typically built with loose stone bound by a mortar of clay. These ghorfa consist of multiple vaulted rooms that are built one on top of the other, up to four stories high. The entrances to the rooms all face inward towards the central courtyard or square of the complex. The upper rooms are accessible by staircases. Another type of fortified granary, consisting of a square structure built in stone, was known as a kasbah (fortress).
In some towns – most famously Matmata – the inhabitants traditionally lived in underground dwellings. These consist of circular pits dug into the soft ground, with various rooms dug into the sides of the pit. Historical records mention the existence of such dwellings as far back as the 4th century BC. The pit dwellings were traditionally advantageous for climatic reasons: they were well-isolated from both the desert heat during hot summer days and the cold during winter. The walls of the pit were typically whitewashed in order to reflect sunlight and maximize lighting in the lower levels. There are various accounts and dates concerning the foundation of these settlements by previously nomadic inhabitants of the region. Some estimates place their foundation to around the 14th or 15th century, if not earlier. In the later 20th century many of these homes were abandoned in favour of modern houses, partly due to occurrences of dangerous floods in the 1960s and 1970s that made the underground dwellings unsafe. One of these former underground dwellings was used as a filming location for the first Star Wars movie, serving as the childhood home of Luke Skywalker.
Jerba
The island of Jerba in Tunisia, traditionally dominated by Ibadi Berbers, has a traditional style of mosque architecture that consists of low-lying structures built in stone, roofed with barrel vaults, and covered in whitewash. Their prayer halls are domed and they have short, often round minarets. The mosques are often described as "fortified mosques" because the island's flat topography made it vulnerable to attacks and as a result the mosques were designed partly to act as watch posts along the coast and in the countryside.
References
Architectural history
Berber architecture
Tunisia
Culture of Tunisia | Architecture of Tunisia | [
"Engineering"
] | 5,260 | [
"Architectural history",
"Architecture"
] |
69,737,874 | https://en.wikipedia.org/wiki/Architecture%20of%20Spokane%2C%20Washington | Spokane and its neighborhoods contain a patchwork of architectural styles that give them a distinct identity and illustrate the changes throughout the city's history. Spokane has a rich architectural history for a western city of its size and much of it is a product of its circumstances at the turn of the 20th century when as a rapidly growing city, the Great Fire of 1889 destroyed 32 blocks of the city center which was quickly rebuilt in a more grand fashion by a community flush with money coming from regional mining districts. Many of the architects that found work in the city and building on the blank slate of the downtown commercial district became highly esteemed architects such as Kirtland Cutter, who has been credited with giving the city a distinctive character. In particular, the city has a high concentration of Romanesque Revival style institutional and commercial buildings and American Craftsman bungalow residences. The architecture of Spokane gained national recognition in industry publications in the early 20th century.
In the second half of the 20th century, Spokane again became noticed for its architecture, this time by a new cadre of architects in the modern architecture movement, which flourished in the city. During this period which lasted from 1948 to the mid-1970s, prolific architects in the city such as Warren C. Heylman gave Spokane a great breadth of mid-century architecture. The modernists in Spokane gave the city a new look and were instrumental in the developments, design, and legacy of the Expo '74 World's Fair in what is now Riverfront Park. The city's landscape architecture and park system was strongly influenced by the Olmsted Brothers, who designed a comprehensive plan for Spokane's park system in 1908 and was implemented almost in its entirety with a $1 million ($ in dollars) bond issue in 1910. Manito Park, which was the city's primary community park until 1974, is noteworthy for having a European style formal garden with input from the Olmsted Brothers and a Japanese Garden designed by Nagao Sakurai.
Background
Spokane and its neighborhoods contain a patchwork of architectural styles that give them a distinct identity and illustrate the changes throughout the city's history. Spokane has a rich architectural history for a western city of its size and much of it is a product of its circumstances at the turn of the 20th century. As a rapidly growing city when Great Fire of 1889 destroyed 32 blocks of the city center, Spokane, flush with money coming from regional mines, experienced a building boom on the blank canvas that was the downtown commercial district by now-esteemed architects such as Herman Preusse, Kirtland Cutter, and John K. Dow, who found much work in the city. Much of the buildings built in the years following the Great Fire of 1889 were built of more fire resistant materials such brick, stone, and terra cotta and on a bigger scale and in a more ostentatious fashion than the wooden buildings of a western frontier town that preceded them. Within a year, Spokane had built 100 new buildings. As the city continued to build, it was described as "the best built modern city on the continent" in a 1908 issue of The Western Architect, where the article's author went on to praise the city's architecture as distinctive, unique, and beautiful and in harmony with its setting. After a little more than a decade of work from Spokane's early architects, the city was profiled again in another publication, The Architect and Engineer, where the author muses as to why some larger cities are unable to match Spokane in its architectural footprint.
Architectural styles
Most of Spokane's largest buildings and landmarks are in the downtown commercial district, where many architecturally significant structures were built after the Great Fire of 1889. Many notable Spokane buildings are done in the Romanesque Revival style that was popular for institutional buildings at the turn of the 20th century. Prominent examples of this style include the Great Northern clock tower, Review Building, Cathedral of Our Lady of Lourdes, Peyton Building, The Carlyle, First Congregational Church, and Washington Water Power Post Street substation.
Other well-represented architectural styles include Art Deco (Spokane City Hall, Paulsen Medical and Dental Building, Fox Theater, John R. Rogers High School, City Ramp Garage), Renaissance Revival (Davenport Hotel, Steam Plant Square, Thomas S. Foley Courthouse, Legion Building, San Marco), Neoclassical (Masonic Center, Hutton Building, Bing Crosby Theater), Chicago School (U.S. Bank Building, Liberty Building, Old City Hall) and Modernist (The Parkade, Ridpath Hotel, Bank of America Financial Center). The tallest building in the city, at , is the Bank of America Financial Center. Also of note is the French Renaissance Spokane County Courthouse in West Central (the building on the seal of Spokane County), the English Gothic Cathedral of St. John the Evangelist in Rockwood, the mimetic literalist Benewah Milk Bottles in Riverside and Garland, Tudor and Collegiate Gothic Mount Saint Michael in Hillyard, and the Cambern Dutch Shop Windmill in South Perry.
Religious institutions
The Spokane area has a great number of architecturally significant religious institutions, cathedrals, and churches done in a variety of styles as different denominations sometimes have unique church architectural traditions. The most significant structures are likely the Romanesque Revival Cathedral of Our Lady of Lourdes designed in various stages by a combination of the firms Preusse & Zittel and Julian & Williams. and the English Gothic style Cathedral of St. John the Evangelist designed by Harold Whitehouse. The Cathedral of Our Lady Lourdes concept design is credited to Preusse & Zittel before construction began in 1902 and follows a cruciform plan with the apse on the south end and two 125-foot bell towers flanking the narthex entry on the north side with the nave, transept and aisles featuring ribbed vaults. The cathedral was dedicated in 1907 with Julian & Williams completing the project. The beginning of the story for the Cathedral of St. John the Evangelist begins in 1924, not long after newly arrived bishop, Edward Makin Cross came to town and hatched a plan to put a cathedral on the South Hill to succeed the All Saints Cathedral downtown, and hired church congregant, Harold C. Whitehouse to design it. Touring Europe for design inspiration, he eventually settled on using the English Gothic style with some French influences. The first stage of construction, the nave leading to the high altar was completed in late 1929, allowing for the first mass to be held, ten days before the 1929 stock market crash which led to a halt in construction for almost two decades. Construction resumed in 1948, and the chancel, sanctuary, transepts, and the Gothic tower were completed by 1954. The building is a solid masonry construction featuring a sandstone exterior quarried near Tacoma and sandstone interior from Idaho with some Indiana limestone; the building contains no structural wood or steel.
Other notable works include the Romanesque Revival St. Aloysius Church designed by Herman Preusse, the Gothic Revival Christ the Redeemer Church designed by John K. Dow, Westminster United Church of Christ also by Dow and Worthy Niver, Mount Saint Michael designed by Julius Zittel, First Presbyterian Church designed by Loren L. Rand, the Victorian New Community Church (formerly the Central United Methodist Church), Carpenter Gothic St. Aidan's Anglican Church, Pilgrim Baptist Church, and Manito United Methodist Church. The Manito United Methodist Church was designed by Kirtland Cutter and was modeled after the Basilica of Saint Francis of Assisi.
During the modernist movement in Spokane, some congregations sought not to build traditional churches, instead opting for something more unique. Two notable examples of this are the St. Charles Borromeo Catholic Church by Funk, Murray, and Johnson and the Convent of the Holy Names by Walker & McGough. The St. Charles Catholic Church, which also features art by local artist Harold Balazs and French stained glass artist, Gabriel Loire, is known for its thick unsupported thin shell concrete roof that once was said to be the "largest unbalanced hyperbolic-paraboloid in the world." The Convent of the Holy Names received an A.I.A. honor in 1967 recognizing it as the finest architectural design in the nation for that year.
Educational institutions
Some of Spokane's high schools and educational institutions are historic buildings and notable for their architecture. The first and one of the most striking is the Collegiate Gothic style Lewis and Clark High School designed by Loren Rand. Built in 1910 and 1911, Rand is said to have worked passionately on the project and dedicated an unusual amount of time on research, especially for the architectural embellishments which featured a clock tower and an entryway evoking elements of a European Gothic cathedral. Lewis and Clark High School was listed on the National Register of Historic Places (NRHP) in 2001 following a renovation and expansion. Also listed on the NRHP following a 2009 renovation and expansion is John R. Rogers High School, built in 1932 and designed by John Dow in Art Deco, a rarely used style for a high school, it features zigzags, chevrons, and vegetation etched on its exterior walls. During the years when modernist architecture was flourishing in the city, two high schools were constructed, Shadle Park High School and Joel E. Ferris High School. Shadle Park High School was built in 1957 well after the modernist movement had caught on nationwide and started peaking in the 1950s; as the first school to be constructed in this new forward-thinking, modern style, the high school was highly anticipated to be a bold statement that the city had entered a new era. The architect chosen for the design of the school was Culler, Gale, Martell & Norrie, a local firm that specialized in modern institutional buildings that was affiliated with Perkins and Will out of Chicago. In high contrast to the past high schools made of brick and mortar with symmetric layouts, Shadle Park High School was clad in a concrete and multi-tiered, asymmetrical glass façade and incorporated glass curtain walls and a variety of construction media including composite materials and on the interior it featured an asymmetrical hallway layout with shiny aluminum door frames and stair railings. As a showcase for modern construction, architecture, and education, the $3 million cost of the building was reportedly the most expensive project undertaken in city history. Shadle Park completed a renovation and expansion in 2008, which preserved its appearance and modernized it for the future. The last high school to be built in the city was Ferris High School in 1963. The design is most notable for its open air campus, with buildings connected via breezeways, a concept that was popular in California at the time but was highly unusual for the area and a problematic choice given Spokane's harsh winters. The high school was renovated in 2013 by NAC Architecture, tearing down all but the original Moritz Kundig designed auditorium and a gym that was added in 2007 to create a single wheel-and-spoke looking structure linking the existing buildings with classroom "wings" surrounded by a central mall.
Residential
Single family homes
As an early affluent Spokane neighborhood, the Browne's Addition neighborhood and residences contain the largest variety of residential architecture in the city. These residences are lavish and personalized, featuring many architectural styles that were popular and trendy in the Pacific Northwest from the late 19th century to 1930, such as the Victorian and Queen Anne styles. Some of these notable early Spokane residences include the Patsy Clark Mansion and the Campbell House in Browne's Addition.
The older neighborhoods of the early 20th century, such as West Central, East Central, Emerson/Garfield, Logan, Hillyard, and much of the lower South Hill, feature a large concentration of American Craftsman style bungalows. Of these, Hillyard is the most architecturally intact neighborhood in Spokane where 85 percent of the buildings are designated as being historic. These simple and affordable homes contrast greatly with those built earlier in the highly embellished and extravagant Browne's addition and instead exude a more modern for the time aesthetic that emphasizes decorative restraint, structural honesty, and solid workmanship. The Arts and Crafts or "California bungalow" was popularized and epitomized by the firm Greene and Greene in southern California. In 1911, it became apparent that the developers overbuilt the market and there was a sharp reduction in new home construction for a period of time.
As the city expanded mainly to the north in the middle of the 20th century, the bungalows in the Minimal Traditional style commonplace from the 1930s to the 1950s tend to predominate in the Northwest, North Hill, and Bemiss, Nevada Heights, and Whitman neighborhoods. These early architectural styles occupy the neighborhoods where the integrity of Spokane's street grid pattern is largely intact (especially the former streetcar suburb areas north of downtown and south of Francis Ave.), and the houses have detached carports with backyard alleys for deliveries, and refuse collection.
In the neighborhoods north of Francis Avenue, much of the neighborhood developments are almost exclusively single-family detached homes (such as those in Balboa/South Indian Trail, Five Mile, Town and Country, and Shiloh Hills) and consist of ranch-style houses, which made up the bulk of post World War II era neighborhoods in the country at the time. Ranch style houses of the post World War II era tend to feature two stories, a low pitched roof, horizontally oriented windows, and a prominent chimney. An isolated exception to the post war styles seen north of Francis Avenue is in Country Homes near Whitworth University, which was a real estate development of railroad tycoon Jay P. Graves in the early 1900s and contains an area with the older style bungalows seen elsewhere in the city. Other forms of residential contemporary architecture are prevalent in the north Spokane suburbs and south edges of Spokane as well as in the new Kendall Yards neighborhood north of downtown which is an urban infill development that adheres to New Urbanism design principles.
With the modernist movement strong in Spokane, there are some notable modern residences in the inventory of Spokane houses; modernist residences are almost always architect designed high-style houses. They are distinguished by their exterior with minimal ornamentation, often a flat or sloping roof, clean lines and flat planes with large windows that let the light in. Interior hallmarks of modernist design will often include built in cabinetry and heavy use of partial walls. Spokane has one Neutra house in its inventory, the Fischer House which was built in 1951 by renowned Los Angeles-based architect, Richard Neutra. Neutra came to America to work for Frank Lloyd Wright and was called "one of the world's half-dozen top modern architects" by Time magazine in 1949. The Fischer House is in the International style which for residences is typified by flat roofs, planar surfaces with minimal embellishment; the Fischer House is notably more rustic looking than his works in southern California, being built with wood rather than stucco as he was advised it would be more appropriate to the Pacific Northwest and consistent with the Northwest Regional style. The Sixteenth Avenue House located on the South Hill was designed by the firm Walker & McGough in 1951, and the Brooks House, which was designed by local architect Kenneth Brooks as his personal residence. Another local modernist architect that built personal residence in the style was William Trogdon, his house, the Trogdon house, was built in 1963 and typifies the Northwest Regional style.
Multi-family residences and apartments
In the late 19th and early 20th century in Spokane after the Great Fire of 1889, longer term multifamily residential housing primarily consisted of the single room occupancy (SRO), which was a type of affordable housing with frugal amenities aimed at working class laborers; usually featuring a private room with a window, bed, closet, and sometimes a sink with communal spaces, such as a restroom and shower on each floor and retail spaces on the first floor. These SROs such as the Otis Hotel, and Hotel Upton helped fulfill a need for housing during Spokane's boom years when hundreds of men came to the city by train to seek work in the regional mining and logging camps or work the fields in agriculture. The early commercial-style Otis Hotel is one of the few still extant examples of the over 150 SROs that were constructed during Spokane's most significant period of growth from 1900 to 1910. The pace of construction was such that the December 19, 1903, edition of The Spokesman-Review reported that the city "leads the nation in percentage of residential building construction."
The first "apartment houses", multifamily buildings designed for middle class renters, in the city appeared in the early 1900s. Previously hotels, lodging houses, and boarding houses were the only rentable living spaces available in the city and those accommodations catered predominantly to lower income, transient workers, whereas middle class families either owned or rented homes. Although the first example of the living arrangement was first introduced in New York in 1869, for middle class families, the idea of close living quarters and shared facilities was seen as a burden and unappealing and was slow to gain acceptance, however, the housing crisis in downtown Spokane, where land and space was growing more expensive made the idea of an apartment more desirable because they began to offer luxuries seen in hotels but with a smaller square footage and the convenience of living in the city. The early apartment styles in Spokane were typical of those in other cities, where the earliest offerings enticed tenants with privacy and urban living in a building with a familiar, domestic look that was reminiscent of a large single family home, and later progressed to residences with amenities seen in high-end hotels that maintain a residential look and feel that avoided the railroad apartment style that was common in tenements of the day by creating separate living and dining areas and finally to luxury suites in a boldly tall structure.
Some of the earliest apartment buildings in the city were pioneered by Albert Held, who was the architect behind the Amman, San Marco, Breslin, and Knickerbocker, which still exist today and were added to the National Register of Historic Places as the Apartment Buildings by Albert Held Thematic Group in 1987. This group of buildings are significant because they illustrate the evolution of apartment building design in Spokane. The Amman was built in 1904, and as possibly the first apartment built in Spokane, it typifies the first stage of apartment evolution, with its simple, rectangular and residential appearance and shingled hip roof with a simple interior, while the San Marco (built 1904) and Knickerbocker (built 1911) represent the intermediate stage of development when apartments were designed and looked like exclusive clubs, with highly ornamented façades and imposing entryway porticos along with a reception desk and elaborately designed interiors. The U-shaped and H-shaped buildings offer residents views of landscaped rear courtyards. Finally, the Breslin represents the last stage of early apartment development in Spokane. The six-story structure was built in 1910 and is much taller than the Amman at only one-half stories and is thought to be the tallest residential building built in Spokane prior to World War II. The Neoclassical Revival building has the appearance of a tall office building, with a cell-like repetition of paned glass windows.
The trend of building high luxury apartments with modern conveniences continued into the next decade. Post World War I, Spokane had a population of over 100,000 people and experienced a glut of high end apartment block construction in a wealthy portion of the Cliff/Cannon neighborhood along West Fifth, Sixth, Seventh, and Eighth Avenues. These units attracted aging "old wealth" residents who wished to downsize from maintaining a house and live care-free in an established mixed-use neighborhood close to public transportation and downtown. In many respects, the apartments built during the post World War I period differed very little from the earlier structures in form, height, scale, and method of construction, but architecturally, a trend toward modernism and a more streamlined look was emerging in buildings such as the NRHP-listed Roosevelt Apartments and the Culmstock Arms Apartments, both built in 1929, as opposed to the revivalist styles popular before. The focal point of the six-story apartment block is the central parapet with terra cotta embellishments and a massive "R/A" cartouche above its elaborate front entrance which has a balconette over mahogany-framed doors which are flanked by Corinthian columns and surrounded by Moorish elements and intricate brass filigree light fixtures. One of the most significant advances in apartment design at this time and present in the Roosevelt and Culmstock Arms Apartments was the inclusion of attached one-story automobile garages.
In the 1930s, Spokane was growing and developing outward from the downtown and the surrounding neighborhoods. One example that typifies the apartments the 1930s and 1940s is the NRHP-listed Robinwoods Apartments, in the vicinity of W. Ninth Avenue and Grand Boulevard on what was known as the Fernhill Addition of Spokane's South Hill. Unlike the exclusive club-like apartments that were still popular in the 1920s, the Robinwood Apartments were not built in an established neighborhood on the periphery of downtown but in a suburban development on largely undeveloped land that was only home to pine trees, wild roses, and syringes. Built in 1939, the complex is representative of the typical domestic, multi-family architecture built during the 1930s to 1940s and catered to residents with professional or paraprofessional occupations. Built in the Tudor Revival style, the Robinwood Apartments is an example of a "motel apartment" and consists of two identical Tudor Revival style buildings with a prominent landscaped courtyard in between. The buildings are two stories with a shingled roof and red brick wall cladding and a first floor featuring a red brick veneer and a second floor with a dark brown-colored false half-timbering that contrasts with a crème colored stucco infill. The Robinwood has an attached covered garage available to each unit, which is accessible at-grade through the basement level on the terraced hillside; with the automobile being ubiquitous and replacing the streetcar, a garage had become a common offering for upscale apartments of the time. The courtyard is considered a defining feature of the apartment complex and is accessed via two brick staircases illuminated at night by wrought iron carriage-style light fixtures that lead to a walkway of brick pavers into a lawn and garden planted with coniferous and deciduous trees, shrubs, and flower beds.
The Mid-century Studio Apartment is an apartment block in the Cliff-Cannon neighborhood at the edge of downtown. Designed by the firm McClure & Adkison with Bruce Walker as the lead designer in 1948, the Mid-century Studio Apartment is significant as probably the first modernist buildings in the city with its efficiently designed block structure and wooden-framed side walls.
Bridges
Spokane has some architecturally notable bridges that were built to span a variety of obstacles and designed for various modes of transportation over the years. Many of these bridges were built to span the Spokane River during Spokane's early 20th century boom years and people once referred to Spokane as the "City of Bridges."
Architects
Early architects
In the defining years after the Great Fire of 1889, many lauded architects were working the Spokane area that helped the city breathlessly rebuild into its Age of Elegance. These notable architects include Albert Held, Archibald G. Rigg, John K. Dow, Herman Preusse, Julius Zittel, Loren L. Rand, William W. Hyslop, Willis Ritchie, Gustav Albin Pehrson, Harold C. Whitehouse, Kirtland Cutter, and Karl G. Malmgren. Kirtland Cutter and Karl Malmgren often worked together as partners in their firm, Cutter & Malmgren. Preusse and Zittel, both natives of Germany also worked together in a partnership.
Likely the first trained architect to practice in the city was Herman Preusse, a German immigrant who studied at the College of Architecture in Holzminden before moving to the United States in 1870 and eventually finding himself in Spokane in 1882. As a growing city recently connected to a Northern Pacific railroad line, Spokane officials retained Preusse to plan the design of buildings in the commercial district and help establish an image of Spokane as a progressive, and prosperous emerging city in the west. Although most of his buildings burned up in the Great Fire of 1889, he remained productive and had more building contracts than any other architect in the city following the fire. Some of his most notable surviving works were for the Jesuits at Gonzaga College, where he was hired to do all of their architectural work and was willing to accept land as payment for it. Preusse is known for designing Gonzaga's St. Aloysius Catholic Church, Carnegie Library, Peyton Building, and Fernwell Building.
Kirtland Cutter
The principal architect of many buildings of this period is associated with Kirtland Cutter and his partner, Karl Malmgren as part of the Cutter & Malmgren firm. Cutter, a self-taught architect, spent much of his career working in Spokane and has become the most identifiable figure with early Spokane architecture scene and is credited in large part with giving the city its distinctive character with his "rare architectural force and genius for design". Structures designed by Cutter include the Spokane Club, Washington Water Power Post Street Electric Substation, the architectural embellishments on the Monroe Street Bridge (featured in the city seal), Central Steam Heat Plant, and the Davenport Hotel. In high demand following his firms' design of the Idaho Building at the Chicago World's Fair in 1893, Cutter found work constructing many mansions for mining and railroad magnates such as Patrick "Patsy" Clark and Daniel C. Corbin and son, Austin. Kirtland Cutter gained a reputation of being an architect retained by the very wealthy, which allowed Cutter the freedom to spare no expense with his creations. Arguably his most well known work is the Davenport Hotel. Built lavishly in the Renaissance Revival and Spanish Revival style, the Davenport Hotel cost two million dollars to complete and included new technologies at the time of its opening in September 1914, such as chilled water, elevators, and air cooling. The ornate hotel lobby has been referred to as "Spokane's living room", and in a 1921 edition of The Architect and Engineer the lobby was applauded by the author stating, there are "few if any finer lobbies in America".
Mid-century architects and the modernist movement
After World War II, a construction boom gave a platform and work to a new generation of Spokane architects that were associated with the modern architecture movement and is thought to have begun when the architect Kenneth W. Brooks arrived in the city in 1948. Brooks was employed at Skidmore, Owings & Merrill before moving to Spokane. Other notable architects during this period include Bruce M. Walker, John McGough, Royal McClure, Thomas R. Adkison, William "Bill" Trogdon, and Warren C. Heylman. Royal McClure is distinguished for having studied under pioneering modernist Walter Gropius at Harvard University. For the most part, the portfolio of this handful of productive architects and their partnerships' work eventually gained recognition nationally, receiving national awards, being featured in industry journals and consumer magazines, once again brought attention to the city's architecture scene and changed the face of the city. The modernist movement deliberately and disruptively broke away from the architectural styles of the past and embraced functionalism and rationalism and used new and innovative materials and construction methods. Modernist architecture encompasses a variety of styles but is broadly characterized by its place in time-post World War II era architecture in the 20th century and the aesthetic associated with it, characterized by the experimental and progressive trends in materials or construction. Modernist architecture eschewed the excessive ornamentation and embellishments that came before in favor of simplicity in design and form, highlighting horizontal and vertical lines and exposing construction materials such as wood and stone to complement a structures natural surroundings.
Notable buildings constructed in this period include the Brutalist style Spokane Civic Theatre and Temple Beth Shalom, the Googie style Dick's Hamburgers, and Shadle Park Reservoir, the Neo-expressionist style Sacred Heart Catholic Church, and the original portions of the Spokane International Airport and Concourses A and B, and the New Formalist style Thomas S. Foley U.S. Courthouse, and The Parkade parking garage. Among the most lauded buildings of this era of architecture in Spokane is the Washington Water Power Central Service Facility (Avista headquarters building) situated on a suburban campus on the banks of the Spokane River. The building was designed by Brooks & Walker in 1958 using the then-popular curtain wall construction, where panels or spandrels are attached to a non-structural framework on the outside of the building, which is meant to bring more light into the interior spaces. Also working on the project was Spokane artist Harold Balazs and San Francisco-based Lawrence Halprin doing the landscape architecture. The building was featured in the magazine Architectural Record and received a First Honor Award award by the American Institute of Architects (AIA), deeming it to be one of the five best buildings built in the country in 1959.
Some of the most prominent examples of modernist architecture came as a result of the preparations for the environmentally-themed Expo '74 World's Fair in what is now Riverfront Park. The modernist architects in Spokane, especially Kenneth Brooks, were keenly aware of the need for urban renewal downtown and "reclaiming the falls" and were active in the groups that shaped the developments that led up to Expo '74. The Fair design was largely the work of Tom Adkison and the firm Trogdon, Smith, and Grossmann and the most significant legacy structures of the fair, the Spokane Convention Center and First Interstate Center for the Arts were designed by Walker & McGough. Adkison, as executive architect was responsible for the overall development of the site while other architects were responsible for the exhibition structures. The environmental theme led to a minimalist design and construction with recycling in mind. After a request for proposal, the final contract to design the recognizable U.S. Pavilion was awarded to Seattle-based architecture firm Naramore, Bain, Brady & Johanson, now known as NBBJ. The building featured a soft shell canopy over a courtyard and a theater, with the translucent roof providing the building with natural light and fresh air. The design of the pavilion was described by the U. S. Department of Commerce as "an expression of environmental concern ... [with the] structure's smooth, graceful contour harmonized fully with the surrounding shoreline terrain". In the 2016 redevelopment and modernization of Riverfront Park, Olson Kundig Architects was contracted to conceptualize the design of the new structures and grounds, paying homage to the fairs original themes; one of the principal architects of the firm, Tom Kundig, was raised in Spokane and is the son of architect Moritz Kundig, who had a leading role in the firm who did the design of the same grounds to prepare for Expo '74.
In 2016, a study was conducted partly funded through a grant by the National Park Service and Washington State Department of Archaeology and Historic Preservation to document examples of the modernist movement in the city and help understand why it flourished in Spokane. The study counted 53 never before inventoried structures built by 27 architects from 1948 to 1973, of which 16 are commercial buildings, 13 are institutional, and 24 are residences. Some of the partnerships and firms created by the Spokane area modernists survive today in some form through mergers, such as NAC Architecture, Integrus Architecture, and ALSC Architects.
Warren C. Heylman
Warren C. Heylman is considered one of the city's foremost and influential architects in contemporary times and is credited with giving the city a great breadth of mid-century architecture. A native of Spokane, after studying engineering at the University of Kansas, he returned to Spokane to briefly work for G.A. Pehrson and Whitehouse & Price before starting his own firm in 1952. Heylman's career was most prolific during the 1960s and 1970s, where his main body of work was designing numerous residential houses, apartment buildings, and architectural embellishments. During Expo '74, Warren designed all of the international exhibition structures with the exception of the Chinese Pavilion. Some of his most noteworthy works in Spokane include The Parkade, Spokane International Airport, Spokane Regional Health Building, Cathedral Plaza, Riverfalls Tower, and the Burlington Northern Latah Creek Bridge over Hangman Valley. Before retiring in 1984, he received six AIA awards, a Concrete Institute Award (for the Parkade), and was inducted into the American Institute of Architects College of Fellows in 1983. The Riverfalls Tower was the first Heylman building in the city to be listed on the local historic register in 2021, listed two years before reaching the usual 50-year mimumum age guideline so the 98-year old Heylman could appreciate the event.
Historic preservation
Since the revitalization of Spokane's historic downtown core at the beginning of the 21st century after decades of suburbanization and losing foot-traffic to the suburbs where there was easy, plentiful parking, there has been renewed interest in the center of the city as a destination. There are three National Register Historic Districts downtown and about half the buildings are designated as historic. Some buildings during the decline amidst suburbanization were demolished simply to make way for parking lots for businesses.
Attitudes appreciative to historic preservation have been growing among some developers, moving more toward attempting to renovate, reuse or repurpose historic and architecturally significant buildings, and big successes came with the renovations of the Davenport Hotel in 2002 and the Fox Theater in 2007, both of which were under threat of demolition; the site of the Fox Theater was to become a parking garage.
Some historic buildings still have been lost to the wrecking ball however. A building that had a noticeable impact for preservation advocates and the community was the demolition of the Rookery Block in 2006 to make way for a potential office high-rise; the Rookery Block to some developers was deemed not economical to renovate, but some in the community saw it as architecturally interesting and worthy of being saved. The Rookery was demolished and today (as of January 2022) is still a public surface parking lot. Although a loss for preservationists, the situation was able to be used to lobby the city council to adopt an ordinance that prohibits the demolition of "historically eligible" buildings without erecting another structure in their place. A nomination was prepared for the Rookery Block, which originally consisted of three buildings, but it was demolished before it could be submitted.
Locally, eligible historic residential properties can apply to be listed on the Spokane Register of Historic Properties, which would make a property eligible for a federal tax credit toward necessary maintenance of the house; the register has over 400 listings (as of August 2021), most of which are residential homes. The Spokane Historic Preservation Office can offer support with the involved process of applying for the register and offer ideas and feedback when renovating a historic property, the Spokane Public Library's Northwest Room can also be used as a resource for finding relevant information regarding public records, newspapers, and neighborhood history in this process.
Most Endangered Places
The Washington Trust for Historic Preservation keeps a "Most Endangered Places" list for historic structures that are believed to be threatened with demolition. In Spokane County, there are currently (as of January 2022) two buildings on the list, the Jensen-Byrd Building and the Chancery Building.
The Jensen-Byrd Building in the University District is a former warehouse designed by Whitehouse & Price with low ceilings which poses unique challenges for adaptive reuse and the Chancery Building is a Kirtland Cutter building that is a contributing property in the Riverside Avenue Historic District, which had its tenant vacated in 2019 to make way for an apartment building.
Landscape architecture
Parks
The Spokane Parks and Recreation Department has of parkland (as of February 2022) on 87 parks in total. Spokane's park system is ranked 17th in the country (as of 2022) based on its ParkScore Index, a ranking methodology by the Trust for Public Land which derives its score from five metrics: acreage, investment, amenities, access, and equity.
From very early on, the city had high ambitions for its park system. Hoping to make the city into a leader in modern park planning, the first city Park Board president, Aubrey White, hired the nations' foremost landscape architecture firm, the Olmsted Brothers to design the nascent park system in 1907. Aubrey saw and admired the City Beautiful movement and the work of the Olmsteds on the East Coast (who most famously designed Central Park in New York City) and wanted to plan ahead to avoid the ill effects of rapid industrialization on a future park system. Aubrey opted to swiftly and preemptively acquire land while it was cheap and before the city expanded and it could be used for future private development. The Olmsteds toured the city and its landscapes and delivered a report in 1908 that ambitiously proposed major improvements to the city's existing parks (like Manito Park, Corbin Park, Adams Park/Cannon Hill Park, and Liberty Park) as well as four large parks, five smaller parks, and 11 playfields. The plan was modeled after similar ones the firm had drawn up for Seattle and Portland. Aubrey and other members of the parks commission envisioned turning Spokane into a "City of Parks", with a comprehensive and cohesive park system, and thus implemented the entirety of the Olmsted Brothers plan for the whole city. The plan was implemented with the narrow passage of a $1 million ($ in dollars) bond by 18 votes in 1910 and parks such as John A. Finch Arboretum, High Bridge Park, and Downriver Park are a result of the Olmsteds recommendations that were in the Olmsted Report revealed in 1913. The legacy that the Olmsted Brothers had on the city park system and their philosophy continue to be revisited by the city Parks and Recreation Department today.
As the Olmsteds envisioned, the city did eventually "come to its senses" and reclaim the downtown riverfront and falls for a park, Riverfront Park, following Expo '74. Post Expo '74, the contract to convert the site to a park was awarded to the landscape architecture firm Robert Perron and Associates. Perron sought to accentuate the site's natural features such as the upper and lower falls by using observation points that were previously occupied by industrial buildings and warehouses, train tracks, and parking lots. Flowing footpaths connect the various sites and follow the terraformed landscape, revealing elements and viewpoints around the edges of the park, at the center of which is a natural amphitheater. The more developed southern edge of the park adjacent to the downtown central business district features the more artificial and manicured elements of the park, such as green spaces, fountains, and pools while the northern edge retains a more rugged aesthetic that more closely resembles the appearance of the natural environment.
Prior to Riverfront Park, the primary community park for the city of Spokane for most of the last century has been Manito Park on the South Hill; originally called Montrose Park, the site had seen recreational use since 1886 and by 1904 when it was officially dedicated, it had obtained its present name which means "Spirit of Nature" in Algonquian. The park has a mirror pond, five distinct gardens, including the European style Duncan Gardens and Nishinomiya Tsutakawa Japanese Garden in addition to the Joel E. Ferris Perennial Garden, Lilac Garden, and Rose Hill as well as a conservatory, the Gaiser Conservatory. The symmetrical Duncan Gardens, designed by John Duncan and redesigned some by the Olmsted Brothers, features a granite fountain and gazebo and the beds are changed seasonally. The Nishinomiya Tsutakawa Japanese Garden is named for Spokane's Japanese sister city, Nishinomiya and Ed Tsutakawa, the local man who campaigned for the twinning relationship; the garden was designed by landscape architect Nagao Sakurai in 1967, who had once maintained the grounds of the Tokyo Imperial Palace and contains a waterfall, pond and bridge. The park was placed on the National Register of Historic Places in 2015.
Parkways
Spokane has some notable parkways. In addition to Manito Park, Manito Boulevard is a tree-lined parkway that leads up to the park that is used for various recreational activities such as walking or jogging. Other parkways such as Rockwood Boulevard and High Drive Parkway were developed with input from the Olmsteds. The Olmsted-designed Rockwood neighborhood has a parkway and also four "Triangle Parks". High Drive Parkway is described as "a picturesque driveway lying on the high bluff in the southwest portion of the city overlooking the Latah Creek valley" in the Olmsted Report to the city Park Board and has park benches and car pull outs for sightseeing; along High Drive is also High Drive Bluff Park that features of trails popular for dog walking, hiking, running, and biking. Other boulevards have green infrastructure such as a sponge city solution on Country Homes Boulevard in north Spokane, which replaced an asphalt stormwater flood control channel with a bioswale with elm and birch trees and foliage like wood sage, blue oat grass, and lilac in 2013.
Urban forestry
The city Parks and Recreation Department manages about 78,000 trees on its parkland as well as lining the city streets in its Urban Forestry Program. To increase the distribution of street trees, the city urban forestry program partners with The Lands Council, a local organization with a mission to "ensure every neighborhood has access to trees and green space". The city has the goal to increase the tree canopy coverage from 23 percent to 40 percent by 2030.
References
Further reading
External links
Spokane City/County Historic Preservation Office Historic Landmarks Commission
Mid-century Spokane Study webpage and the 2017 Mid-Century Survey Report: City of Spokane Mid-20th Century Modern Context Statement and Inventory
Modern Architecture Spokane, Washington State Department of Archaeology and Historic Preservation
Spokane Preservation Advocates
Architecture in the United States by city
Architecture in Washington (state)
Buildings and structures in Spokane, Washington
Landscape architecture | Architecture of Spokane, Washington | [
"Engineering"
] | 8,594 | [
"Landscape architecture",
"Architecture"
] |
69,741,485 | https://en.wikipedia.org/wiki/Koala%20conservation | Koala conservation organisations, programs and government legislation are concerned with the declining population of koalas (Phascolarctos cinereus), a well known Australian marsupial found in gum trees. The Australian government declared the species as endangered by extinction in 2022.
While the koala was previously classified as Least Concern on the Red List, it was uplisted to Vulnerable in 2016. Australian policy makers declined a 2009 proposal to include the koala in the Environment Protection and Biodiversity Conservation Act 1999. In 2012, the Australian government listed koala populations in Queensland and New South Wales as Vulnerable, because of a 40% population decline in the former and a 33% decline in the latter. A 2017 WWF report found a 53% decline per generation in Queensland, and a 26% decline in New South Wales. Populations in Victoria and South Australia appear to be abundant; however, the Australian Koala Foundation argues that the exclusion of Victorian populations from protective measures is based on a misconception that the total koala population is 200,000, whereas they believe it is probably less than 100,000.
History
Koalas were hunted for food by Aboriginals. A common technique used to capture the animals was to attach a loop of ropey bark to the end of a long, thin pole, so as to form a noose. This would be used to snare an animal high in a tree, beyond the reach of a climbing hunter; an animal brought down this way would then be killed with a stone hand axe or hunting stick (waddy). According to the customs of some tribes, it was considered taboo to skin the animal, while other tribes thought the animal's head had a special status, and saved them for burial.
The koala was heavily hunted by European settlers in the early 20th century, largely for its thick, soft fur. More than two million pelts are estimated to have left Australia by 1924. Pelts were in demand for use in rugs, coat linings, muffs, and as trimming on women's garments. Extensive cullings occurred in Queensland in 1915, 1917, and again in 1919, when over one million koalas were killed with guns, poisons, and nooses. The public outcry over these cullings was probably the first wide-scale environmental issue that rallied Australians. Novelist and social critic Vance Palmer, writing in a letter to The Courier-Mail, expressed the popular sentiment:
The shooting of our harmless and lovable native bear is nothing less than barbarous ... No one has ever accused him of spoiling the farmer's wheat, eating the squatter's grass, or even the spreading of the prickly pear. There is no social vice that can be put down to his account ... He affords no sport to the gun-man ... And he has been almost blotted out already from some areas.
Despite the growing movement to protect native species, the poverty brought about by the drought of 1926–1928 led to the killing of another 600,000 koalas during a one-month open season in August 1927. In 1934, Frederick Lewis, the Chief Inspector of Game in Victoria, said that the once-abundant animal had been brought to near extinction in that state, suggesting that only 500–1000 remained.
The first successful efforts at conserving the species were initiated by the establishment of Brisbane's Lone Pine Koala Sanctuary and Sydney's Koala Park Sanctuary in the 1920s and 1930s. The owner of the latter park, Noel Burnet, became the first to successfully breed koalas and earned a reputation as the foremost contemporary authority on the marsupial. In 1934, David Fleay, curator of Australian mammals at the Melbourne Zoo, established the first Australian faunal enclosure at an Australian zoo, and featured the koala. This arrangement allowed him to undertake a detailed study of its diet in captivity. Fleay later continued his conservation efforts at Healesville Sanctuary and the David Fleay Wildlife Park.
Modern threats
One of the biggest anthropogenic threats to the koala is habitat destruction and fragmentation. In coastal areas, the main cause of this is urbanisation, while in rural areas, habitat is cleared for agriculture. Native forest trees are also taken down to be made into wood products. In 2000, Australia ranked fifth in the world by deforestation rates, having cleared . The distribution of the koala has shrunk by more than 50% since European arrival, largely due to fragmentation of habitat in Queensland. The koala's "vulnerable" status in Queensland and New South Wales means that developers in these states must consider the impacts on this species when making building applications. In addition, koalas live in many protected areas.
While urbanisation can pose a threat to koala populations, the animals can survive in urban areas provided enough trees are present. Urban populations have distinct vulnerabilities: collisions with vehicles and attacks by domestic dogs. To reduce road deaths, government agencies have been exploring various wildlife crossing options, such as the use of fencing to channel animals toward an underpass, in some cases adding a ledge as walkway to an existing culvert. Dogs kill about 4,000 animals every year.
Koala populations and habitat were impacted by the 2020 bushfires. A local veterinarian estimated as many as 30,000 may have died in the Kangaroo Island fires, out of an estimated population of 50,000. Another predicted negative outcome of climate change is the effect of elevations in atmospheric levels on the koala's food supply: increases in cause Eucalyptus trees to reduce protein and increase tannin concentrations in their leaves, reducing the quality of the food source. In June 2020, a New South Wales parliamentary committee released a report stating that koalas could be extirpated from the state by 2050. Recommendations included establishing national parks on the Georges River and Mid-North Coast.
Droughts also affect the koala's well-being. For example, a severe drought in 1980 caused many Eucalyptus trees to lose their leaves. Subsequently, 63% of the population in southwestern Queensland died, especially young animals that were excluded from prime feeding sites by older, dominant koalas, and recovery of the population was slow. Later, this population declined from an estimated mean population of 59,000 in 1995 to 11,600 in 2009, a reduction attributed largely to hotter and drier conditions resulting from droughts in most years between 2002 and 2007. According to Australian environment minister Sussan Ley, the 2019–20 Australian bushfire season, and especially fires in NSW, resulted in the death of up to 8,400 koalas (30% of the local population) on New South Wales's mid-north coast.
The ability of koalas to withstand increasing temperatures associated with climate change is a growing concern for conservation efforts and has prompted research into how to monitor koalas’ body temperature at a distance. A team of scientists devised a non-invasive method to determine koala temperature using a thermal camera and thermal imaging software tools. The scientists found that the eyes of koalas yielded the most consistent temperature recordings of all body parts but were the most difficult structure to record.
Rescue and rehabilitation
Injured koalas are often taken to wildlife hospitals and rehabilitation centres. In a 30-year retrospective study performed at a New South Wales koala rehabilitation centre, trauma (usually resulting from a motor vehicle accident or dog attack) was found to be the most frequent cause of admission, followed by symptoms of Chlamydia infection.
Wildlife caretakers are issued special permits, but must release the animals back into the wild when they are either well enough or, in the case of joeys, old enough. As with most native animals, the koala cannot legally be kept as a pet in Australia or anywhere else. One virtually unknown risk to koalas is that of water in the lungs (aspiration pneumonia), which can happen when drinking water from a bottle, as seen in numerous viral videos of well-meaning, but uninformed, people giving thirsty koalas water bottles to drink. The safer way to provide a koala drinking water is via a bowl, cup, helmet or hat from which the koala can lap up the water it needs.
Introductions
Since 1870, koalas have been introduced to several coastal and offshore islands, including Phillip Island (Victoria) and Kangaroo Island (South Australia). Their numbers have significantly increased, and since the islands are not large enough to sustain such high koala numbers, overbrowsing has become a problem.
Since the 1990s, government agencies have tried to control their numbers by culling, but public and international outcry has forced the use of translocation and sterilisation, instead.
Western Port Islands, Victoria
In the 1920s, Lewis initiated a program of large-scale relocation and rehabilitation programs to transfer koalas whose habitat had become fragmented or reduced, to new regions, with the intent of eventually returning them to their former range.
In 1929 the koala population on Phillip Island collapsed with the death of their manna gums, officially attributed to insect pests and fire. In 1930–31, 165 survivors were translocated to French Island and Quail Island.
The koalas on Quail Island thrived until 1943, when those on one half of the island were found to be dying from starvation After a period of population growth, and subsequent overbrowsing of gum trees on the island, about 1,300 animals were released into mainland areas in 1944.
The koalas on French Island also prospered and multiplied until in 1954, faced with dying trees, the population of 700 was moved to the mainland, in the vicinity of Camperdown and Ararat.
The practice of translocating koalas became commonplace; Victorian State manager Peter Menkhorst estimated that from 1923 to 2006, about 24,000 animals were translocated to more than 250 release sites across Victoria.
Kangaroo Island, South Australia
Kangaroo Island, commonly referred to as "K.I.", is one of Australia's largest islands, situated some 20km off the coast of South Australia, and had no historical koala population. Subspecies of the manna gum Eucalyptus viminalis, a favoured food of koalas, occur on the island.
Flinders Chase National Park, at the far west of the island, was set up in the early 20th-century as a habitat for Australian mammals and birds whose survival on the mainland was threatened, especially from foxes and rabbits, from which the island is free.
In 1923 six "native bears", as the koala was then popularly known, were donated by the National Park of Victoria, Wilson's Promontory, and taken across to KI on the Karatta in November 1923 by three members of the Fauna and Flora Board: J. C. Marshall, professors T. G. Osborn and Wood Jones, and Edgar R. Waite, director of the Adelaide Museum.
Another six pair, with young, were released by the board in 1925.
The population grew steadily: in 1934 researchers located several with difficulty, living on Eucalyptus ovata and the yellow gum E. leucoxylon; in 1943 a census found nearly 300, and in 1949 another team saw 18 full-grown adults in a quarter of a mile (some (400m), living on manna gums, pink gums (E. fasciculosa), and water gums.
By the 1990s the koala population had grown to the extent that they were consuming the leaves of their eucalypts at a rate beyond the trees' capacity to regenerate, and it was clear to scientists and others that some form of human intervention was necessary to avoid wholesale death of trees and distress to the koalas.
In 1996 (Liberal) conservation minister David Wotton appointed a panel of experts led by Hugh Possingham to examine the problems and recommend solutions. Their unanimous recommendation was humane culling (i.e. shooting) to reduce their numbers. The government however ruled out such action on public relations grounds — the tourist industry, on which the economies of South Australia and Kangaroo Island were highly dependent, would be greatly affected by hostile publicity, abetted by activists such as the Australian Koala Foundation. They chose instead a program of trapping and sterilization (tubal ligation under general anaesthetic) of selected females, who were then released on the mainland, a process which may be distressing to the animal, and very expensive given the number which had to be treated, but kinder, they said, than killing. By 2001 they had sterilized 3,400 adults and relocated another thousand, but had not even matched the "natural increase" of the population of some 27,000 individuals. And it cost $2,400 for each relocated koala.
A study of those relocated individuals found that they wandered far from their release site and most gained weight but more than one third died in the first year after relocation.
Notes
References
Koalas
Conservation dependent biota of Australia
Wildlife conservation | Koala conservation | [
"Biology"
] | 2,668 | [
"Wildlife conservation",
"Biodiversity"
] |
69,741,788 | https://en.wikipedia.org/wiki/Soraya%20de%20Chadarevian | Soraya de Chadarevian is a historian of molecular biology and a professor in the Department of History and the Institute for Society and Genetics at the University of California, Los Angeles. She has numerous publications on the history of molecular life sciences.
Education
Soraya de Chadarevian completed a five-year Diploma course in biology at the University of Freiburg, Germany and continued with a year of experimental work at the University of Bologna, Italy. She has then held many fellowships including the Walther Rathenau Program and the Max Planck Institute for History of Science in Berlin, Social Research at the Hamburg Institute, Churchill College at Cambridge, and the Institute for Advances Studies in the Humanities at the University of Edinburgh.
References
Molecular-biology-related lists
Living people
Year of birth missing (living people) | Soraya de Chadarevian | [
"Chemistry"
] | 159 | [
"Molecular biologists",
"Biochemists",
"Molecular biology"
] |
69,741,859 | https://en.wikipedia.org/wiki/M17%20%28amateur%20radio%29 | M17 is a digital radio modulation mode developed by Wojciech Kaczmarski (amateur radio call sign SP5WWP) et al. M17 is primarily designed for voice communications on the VHF amateur radio bands, and above. The project received a grant from the Amateur Radio Digital Communications in 2021 and 2022.
The protocol has been integrated into several hardware and software projects. In 2021, Kaczmarski received the ARRL Technical Innovation Award for developing an open-source digital radio communication protocol, leading to further advancements in amateur radio.
Technical characteristics
M17 uses Frequency-Division Multiple Access (FDMA) technology in which different communication streams are separated by frequency and run concurrently. It utilizes 4,800 symbols per second, 4-level frequency-shift keying (4FSK) with a root Nyquist filter applied to the bitstream. Radio channels are 9 kHz wide, with channel spacing of 12.5 kHz. The gross data rate is 9,600 bits per second, with the actual data transfer at 3,200. The transmission, called stream, is divided into 40-millisecond long frames, each prepended with a 16-bit long synchronization word. A group of 6 frames form a superframe and is needed to decode the link information data.
Protocol allows for low-speed data transfer (along with voice), e.g. GNSS position data.
The mode has been successfully transmitted through EchoStar XXI and QO-100 geostationary satellites.
The protocol's specification is released under GNU General Public License.
Voice encoding
M17 uses Codec 2, a low bitrate voice codec developed by David Rowe VK5DGR et al. Codec 2 was designed to be used for amateur radio and other high compression voice applications. It is based on linear predictive coding with mixed-harmonic sinusoidal excitation. The protocol supports both 3200 (full-rate) and 1600 bits per second (half-rate) modes.
Error control
Three methods are used for error control: binary Golay code, punctured convolutional code and bit interleaving. Additionally, exclusive OR operation is performed between data bits and a predefined decorrelating pseudorandom stream before transmission. This ensures that there are as many symbol transitions in the baseband as possible. A 16-bit cyclic redundancy check (CRC) code is used for data integrity assurance.
Application functions
The M17 protocol was primarily designed for amateur radio use.
Callsign encoding: 48-bit field holding up to 9 alphanumeric characters eliminates the need of a centralized user-ID database.
Stream and packet modes of operation.
Stream mode offers one 3200bps net bitrate channel (encoded speech or data) or two 1600bps channels (encoded speech alongside data).
Packet mode supports text messaging, APRS and AX.25.
Slow-speed side channel for short and repeated data transfers, e.g. GNSS position data or telemetry.
Encryption:
Bit scrambler encryption: a pseudorandom binary sequence created by combining an exclusive-or bitwise operation on the audio or data stream and a linear-feedback shift register using one of 3 feedback polynomials with 255, 65,535 and 16,777,215-bit repeat periods.
AES encryption: 128-bit block encryption cipher operating in CTR mode with user-selectable 128, 192 or 256-bit key.
Hardware support
With a small hardware modification, TYT MD-380, MD-390 and MD-UV380 handheld transceivers can be flashed with a custom, free, open source firmware to enable M17 support.
In July 2024, a US-based company Connect Systems, Inc. released the CS7000-M17, being the first commercial off-the-shelf handheld transceiver with native M17 support.
Bridging with other modes
Links between M17 and other digital voice modes and Internet linked networks exist, with several networks providing M17 access. Modes bridged include DMR, P25, System Fusion, D-STAR, NXDN, AllStarLink, EchoLink and IRLP.
Comparison with other standards
M17 over IP
Access nodes and repeaters can be linked using reflectors. Over 200 M17 reflectors exist worldwide (November 2024).
History
The project was started in 2019 by Wojciech Kaczmarski in Warsaw, Poland. A local amateur radio club he was a member of, was involved in digital voice communications. Kaczmarski, having experimented with TETRA and DMR, decided to create a completely non-proprietary protocol and named it after the club's street address - Mokotowska 17. As every part of the protocol was intended to be open source, Codec 2, released under the GNU LGPL 2.1 license, was chosen as the speech encoder.
Applications and projects with M17 support
OpenRTX - free and open-source firmware for ham radios
WPSD - digital voice software suite for amateur radio personal hotspots and repeaters
DroidStar - digital voice client for Android
Multi-mode Digital Voice Modem (MMDVM)
SDR++ - multiplatform, open-source software defined radio receiver
SDRangel - multiplatform, open-source software defined radio receiver/transmitter
OpenWebRX - web-based software defined radio receiver
mrefd - M17 reflector
rpitx - general radio frequency transmitter for Raspberry Pi
dsd-fme - digital speech decoder
mvoice - voice client and graphical repeater application (Raspberry and Linux)
See also
NXDN
D-STAR
Speech coding
Quadratic permutation polynomials (QPP)
References
Related links
M17 Project's website
M17 Project on GitHub
Twitter feed
WPSD project page
Robert Riggs' (WX9O) M17 baseband encoder/decoder library (C++, GPL)
OpenWebRX - web based SDR by Jakob Ketterl (DD5JFK), includes M17 decoder
SDR++ - free, open source SDR software with M17 support
mvoice - an open source program to connect to M17 reflectors
Article on the M17 Project in the Radio Society of Great Britain's RadCom magazine
Quantized radio modulation modes
Digital amateur radio | M17 (amateur radio) | [
"Technology"
] | 1,336 | [
"Wireless networking",
"Digital amateur radio"
] |
69,743,250 | https://en.wikipedia.org/wiki/Courant%E2%80%93Snyder%20parameters | In accelerator physics, the Courant–Snyder parameters (frequently referred to as Twiss parameters or CS parameters) are a set of quantities used to describe the distribution of positions and velocities of the particles in a beam. When the positions along a single dimension and velocities (or momenta) along that dimension of every particle in a beam are plotted on a phase space diagram, an ellipse enclosing the particles can be given by the equation:
where is the position axis and is the velocity axis. In this formulation, , , and are the Courant–Snyder parameters for the beam along the given axis, and is the emittance. Three sets of parameters can be calculated for a beam, one for each orthogonal direction, x, y, and z.
History
The use of these parameters to describe the phase space properties of particle beams was popularized in the accelerator physics community by Ernest Courant and Hartland Snyder in their 1953 paper, "Theory of the Alternating-Gradient Synchrotron". They are also widely referred to in accelerator physics literature as "Twiss parameters" after British astronomer Richard Q. Twiss, although it is unclear how his name became associated with the formulation.
Phase space area description
When simulating the motion of particles through an accelerator or beam transport line, it is often desirable to describe the overall properties of an ensemble of particles, rather than track the motion of each particle individually. By Liouville's Theorem it can be shown that the density occupied on a position and momentum phase space plot is constant when the beam is only affected by conservative forces. The area occupied by the beam on this plot is known as the beam emittance, although there are a number of competing definitions for the exact mathematical definition of this property.
Coordinates
In accelerator physics, coordinate positions are usually defined with respect to an idealized reference particle, which follows the ideal design trajectory for the accelerator. The direction aligned with this trajectory is designated "z", (sometimes "s") and is also referred to as the longitudinal coordinate. Two transverse coordinate axes, x and y, are defined perpendicular to the z axis and to each other.
In addition to describing the positions of each particle relative to the reference particle along the x, y, and z axes, it is also necessary to consider the rate of change of each of these values. This is typically given as a rate of change with respect to the longitudinal coordinate (x' = dx/dz) rather than with respect to time. In most cases, x' and y' are both much less than 1, as particles will be moving along the beam path much faster than transverse to it. Given this assumption, it is possible to use the small angle approximation to express x' and y' as angles rather than simple ratios. As such, x' and y' are most commonly expressed in milliradians.
Ellipse equation
When an ellipse is drawn around the particle distribution in phase space, the equation for the ellipse is given as:
"Area" here is an area in phase space, and has units of length * angle. Some sources define the area as the beam emittance , while others use . It is also possible to define the area as a specific fraction of the particles in a beam with a 2 dimensional gaussian distribution.
The other three coefficients, , , and , are the CS parameters. As this ellipse is an instantaneous plot of the positions and velocities of the particles at one point in the accelerator, these values will vary with time. Since there are only two independent variables, x and x', and the emittance is constant, only two of the CS parameters are independent. The relationship between the three parameters is given by:
Derivation for periodic systems
In addition to treating the CS parameters as an empirical description of a collection of particles in phase space, it is possible to derive them based on the equations of motion of particles in electromagnetic fields.
Equation of motion
In a strong focusing accelerator, transverse focusing is primarily provided by quadrupole magnets. The linear equation of motion for transverse motion parallel to an axis of the magnet is:
where is the focusing coefficient, which has units of length−2, and is only nonzero in a quadrupole field. (Note that x is used throughout this explanation, but y could be equivalently used with a change of sign for k. The longitudinal coordinate, z, requires a somewhat different derivation.)
Assuming is periodic, for example, as in a circular accelerator, this is a differential equation with the same form as the Hill differential equation. The solution to this equation is a pseudo harmonic oscillator:
where A(z) is the amplitude of oscillation, is the "betatron phase" which is dependent on the value of , and is the initial phase. The amplitude is decomposed into a position dependent part and an initial value , such that:
(It is important to remember that ' continues to indicated a derivative with respect to position along the direction of travel, not time.)
Particle distributions
Given these equations of motion, taking the average values for particles in a beam yields:
These can be simplified with the following definitions:
giving:
These are the CS parameters and emittance in another form. Combined with the relationship between the parameters, this also leads to a definition of emittance for an arbitrary (not necessarily Gaussian) particle distribution:
Properties
The advantage of describing a particle distribution parametrically using the CS parameters is that the evolution of the overall distribution can be calculated using matrix optics more easily than tracking each individual particle and then combining the locations at multiple points along the accelerator path. For example, if a particle distribution with parameters , , and passes through an empty space of length L, the values , , and at the end of that space are given by:
See also
Beam emittance
Beta function (accelerator physics)
Ray transfer matrix analysis
References
Accelerator physics | Courant–Snyder parameters | [
"Physics"
] | 1,221 | [
"Accelerator physics",
"Applied and interdisciplinary physics",
"Experimental physics"
] |
69,744,384 | https://en.wikipedia.org/wiki/Weather%20of%202016 | The following is a list of weather events that occurred in 2016.
Global conditions
Monthly summary
Summary by weather type
Winter storms and cold waves
Floods
Droughts, heat waves, and wildfires
Tornadoes
A small tornado outbreak occurred during a winter storm on February 2-3. An EF1 due to the outbreak caused $5.08 million. Three weeks later, the second largest tornado outbreak in February resulted in 7 deaths. The tornado outbreak caused $1.2 billion in damage.
Tropical cyclones
As the year began, a tropical low was over Australia, and Cyclone Ula was moving toward Tonga. Ula was followed by another 16 tropical cyclones, including Cyclone Winston, which was the most intense tropical cyclone in the Southern Hemisphere on record, with 10 minute sustained winds of 280 km/h (175 mph), and a minimum pressure of . At peak intensity, Winston made landfall on Fiji, the strongest ever to hit the country, and one of the strongest landfalls worldwide on record. Damage in Fiji totaled FJ$2.98 billion (US$1.4 billion), and 44 people were killed. In the Australian basin, there were 16 tropical cyclones, which made it the least-active season on record. Activity in the south-west Indian Ocean was also below average, with just tropical cyclones. Among these were Cyclone Fantala in April, which reached 10 minute sustained winds of 250 km/h (155 mph) while near the Seychelles, making it the strongest tropical cyclone on record in the basin.
The first northern hemisphere tropical cyclone was Hurricane Pali, a rare off-season hurricane which formed on January 7 southwest of Hawaii. There were an additional 22 tropical cyclones in the north-east Pacific Ocean during the year, including Hurricane Otto, which crossed from the Caribbean Sea in November, killing 23 people in Central America. Otto was the last of 16 tropical cyclones in the Atlantic Ocean. The first, Alex, was a rare January hurricane which hit the Azores. The strongest Atlantic hurricane of the year was Matthew, which attained 1 minute sustained winds of 165 mph (270 km/h) in the Caribbean. Matthew killed 603 people and left at least US$15 billion in damage after its path through Haiti, Cuba, The Bahamas, and offshore the southeastern United States. In August, Hurricane Earl killed 81 people in southeast Mexico after it struck Belize.
In the north Indian Ocean, there were ten tropical cyclones. Among these were Cyclone Roanu in May, which killed 135 people in Sri Lanka and Bangladesh, causing over US$2 billion in damage. In contrast to the unusually early start to activity in the north-east Pacific and the Atlantic, the first tropical cyclone in the north-west Pacific did not develop until May 25, when a tropical depression formed. It was the first of 51 tropical cyclones during the year. The strongest of the year was Typhoon Meranti, which reached 10 minute sustained winds of 220 km/h (140 mph) while moving through the Batanes in the Philippines. Meranti later struck China, and along its path it killed 47 people, with US$4.79 billion in damage. In July, Typhoon Nepartak killed 111 people and left US$1.89 billion in damage when it struck Taiwan and southeastern China. In August, Typhoon Lionrock became the first storm on record to strike the Tōhoku region of Japan, with 22 deaths in the country and 525 deaths from flooding in North Korea.
Timeline
This is a timeline of weather events during 2016. Please note that entries might cross between months, however, all entries are listed by the month they started.
January
January 12-17 - Hurricane Alex kills one person, and becomes the first Hurricane in January in the Atlantic since 1938.
January 21-29 - A historical blizzard, the most recent to be rated a category 5 on the Regional Snowfall Index scale, causes 55 deaths and between $500 million and $3 billion in damage.
February
A tornado outbreak consisting of 61 tornadoes, the second largest on record for February, caused 7 deaths and $1.2 billion.
March
April
May
May 1 – 2016 Fort McMurray wildfire: a wildfire erupts after record high temperatures in April in northern Alberta, forcing the evacuation of the entire city of Fort McMurray in Alberta. It is the largest mass evacuation in Canadian history. The wildfire destroys more than 3000 buildings, burns nearly 600,000 hectares of land, and causes nearly $10 billion in damages. The wildfire is the costliest natural disaster in Canadians history.
May 7-10 - A tornado outbreak of 57 tornadoes caused 2 deaths, 19 injuries and $1 billion in damage.
May 15 – A nighttime EF2 tornado in Brazil killed four people and injured 21 others.
May 22-26 - A tornado outbreak sequence spawns 98 tornadoes, which caused 11 injuries and $1.3 billion in damage.
June
June 23 - The Jiangsu tornado in China caused 98 deaths and 846 injuries, amounting to $760 million in damage. The tornado was rated EF4. Another unrated tornado caused an additional fatality.
July
August
September
September 9 - Philadelphia, for the first time in history, has a low above in September. The high that day also set a record at .
September 28 - October 10 - Hurricane Matthew unleashes catastrophic damage across the Caribbean Sea (especially in Haiti), and the Southeastern United States, causing 603 deaths and $16.47 billion in damage.
October
November
November 20–26 – Hurricane Otto killed 23 people and caused $192.2 million (2016 USD) in damage across Panama, Costa Rica and Nicaragua. Hurricane Otto was also the first hurricane since 1996 to survive the crossover from the Atlantic Ocean to the Pacific Ocean.
November 27-30 - A tornado outbreak that unleashes 48 tornadoes caused 6 deaths and 55 injuries. It also caused at least $3.7 million in damage according to NOAA, and $275 million according to Aon.
December
December 13 - A man in Florida was struck and killed by lightning. This was the first person to die due to lightning in December since 1998.
References
Weather by year
2016 meteorology | Weather of 2016 | [
"Physics"
] | 1,246 | [
"Weather",
"Physical phenomena",
"Weather by year"
] |
69,744,483 | https://en.wikipedia.org/wiki/CKLF-like%20MARVEL%20transmembrane%20domain-containing%20family | The CKLF-like MARVEL transmembrane domain-containing family (CMTM), previously termed the chemokine-like factor superfamily (CKLFSF), consists of 9 proteins, some of which have various isoforms due to alternative splicing of their respective genes. These proteins along with their isoforms are:
Chemokine-like factor (CKLF), the founding member of this family, has 4 known isoforms, CKLF1 to CKLF4.
CKLF like MARVEL transmembrane domain-containing 1 (CMTM1) has 23 known isoforms, CMTM1-v1 to CMTM1-v23.
CKLF like MARVEL transmembrane domain-containing 2 (CMTM2) has no known isoforms.
CKLF like MARVEL transmembrane domain-containing 3 (CMTM3) has no known isoforms.
CKLF like MARVEL transmembrane domain-containing 4 (CMTM4) has 3 known isoforms, CMTM4-v1 to CMTM4-v3.
CKLF-like MARVEL transmembrane domain-containing 5 (CMTM5) has 6 known isoforms, CMTM5-v1 to CMTM5-v6.
CKLF like MARVEL transmembrane domain containing 6 (CMTM6) has no known isoforms.
CKLF like MARVEL transmembrane domain containing 7 (CMTM7) has 2 isoforms, CMTM7-v1 and CMTM7-v2.
CKLF like MARVEL transmembrane domain-containing 8 (CMTM8) has two isoforms, CMTM8 and CMTM8-v2 (Little is known about the CMTM8-v2 isoform and the CMTM8 isoform is referred to as CMTM8 rather than CMTM8-v1.).
All of these proteins have domains (i.e. regions) similar to analogous domains in the chemokine proteins; tetraspanin proteins (also termed transmembrane-4 superfamily proteins); myelin and lymphocyte protein (also termed MAR protein); proteins that direct membrane vesicle trafficking; and other proteins that are embedded in cell membranes. The genes encoding (i.e. directing the production of) these proteins, CKLF, CMTM1, CMTM2, CMTM3, CMTM4, CMTM5, CMTM6, CMTM7, and CMTM8, respectively, also share similar regions that encode the domains just cited for their proteins. (The 8 CMTM genes were formerly termed CKLFSF1, CKLFSF2, CKLFSF3, CKLFSF4, CKLFSF5, CKLFSF6, CKLFSF7, and CKLFSF8.) The CKLF, CMTM1, CMTM2, CTMT3, and CMTM4 genes cluster together in band 22 on the long (i.e. "q") arm of chromosome 16; the CMTM6, CMTM7, and CMTM8 genes form a second cluster in band 22 on the short (i.e. "p") of chromosome 3; and the CMTM5 gene, located in band 11.2 on the q arm of chromosome 14, is not clustered with the other CMTM genes. These structural similarities and clusterings reflect the close relationships of these proteins and genes. Studies suggest that the members of this family may be involved in the development of various cancers autoimmune diseases, cardiovascular diseases, the male reproductive system, and angiogenesis (i.e. development of new blood vessels from pre-existing blood vessels). In most of these cases, however, further studies are needed to determine if these CMTM proteins and/or their corresponding genes and mRNAs will be promising targets to help in the diagnosis, prognosis, and/or treatment of these disorders.
References
Human proteins
DNA replication
Gene expression
Transcription coregulators | CKLF-like MARVEL transmembrane domain-containing family | [
"Chemistry",
"Biology"
] | 828 | [
"Genetics techniques",
"Gene expression",
"DNA replication",
"Molecular genetics",
"Cellular processes",
"Molecular biology",
"Biochemistry"
] |
69,745,190 | https://en.wikipedia.org/wiki/1%2C1%2C6-Trimethyl-1%2C2-dihydronaphthalene | 1,1,6-Trimethyl-1,2-dihydronaphthalene (TDN) is an aroma compound present in wine, particularly aged Rieslings. Chemically, it is classified as a 13C-norisoprenoid, as it has thirteen carbon atoms, and is derived from an isoprenoid by the loss of methylene groups.
In wines, TDN is generally considered to contribute to a desirable aroma in low concentrations, but an undesirable aroma in higher concentrations. The aroma is commonly described as a petrol note or by the French term goût de pétrole.
TDN is believed to be a degradation product of β-carotene and lutein. TDN can also by synthesized in the laboratory from either of the ionones, α-ionone or β-ionone.
References
Flavors
Terpenes and terpenoids
Oenology | 1,1,6-Trimethyl-1,2-dihydronaphthalene | [
"Chemistry"
] | 188 | [
"Organic compounds",
"Biomolecules by chemical classification",
"Terpenes and terpenoids",
"Natural products"
] |
69,745,198 | https://en.wikipedia.org/wiki/Geist%20%28liquor%29 | (German for 'spirit') is a distilled beverage obtained by maceration of unfermented fruit or other raw materials in neutral spirits, followed by distillation. This differs from fruit brandy, where the alcohol comes from fermenting the fruit's naturally occurring sugars. As such, geist can be made from a much wider range of materials, as it is not limited to fruits with sufficient fermentable sugars.
Geist can be produced from a single material (like Himbeergeist) or a combination of multiple ingredients.
Akvavit, most gins and white absinthes legally meet the description to be considered a geist, although they have more specific legal definitions.
European Union
Geist
As per the EU regulations that define of spirit drinks, geist must be produced by maceration of unfermented fruits and berries or vegetables, nuts, other plant materials, such as herbs, rose petals, or mushrooms, in ethyl alcohol of agricultural origin, followed by distillation.
Geist must contain at least 37.5% alcohol by volume, it cannot contain added colours or flavours, and it may not contain more than 10 grams of sweetening products per litre (expressed as invert sugar).
Spirit obtained by maceration and distillation
Geist can also be named "Spirit obtained by maceration and distillation" only if it has been produced from the following fruits, berries or nuts:
chokeberry
black chokeberry
chestnut
citrus fruits
hazelnut
crowberry
strawberry
sea-buckthorn
hollyberry
cornel cherry or cornelian cherry
walnut
banana
myrtle
prickly pear
passion fruit
bird cherry
sloe
blackcurrant
white currant
redcurrant
gooseberry
rosehip
arctic bramble
cloudberry
blackberry
raspberry
elderberry
rowanberry
sorb apple
wild service tree
ambarella
hog plum
high bush blueberry
wild cranberry
bilberry/blueberry
cowberry
Elderberry geist can therefore be named "Elderberry spirit obtained by maceration and distillation" but elderflower geist cannot.
See also
Eau de vie
Liquor
List of alcoholic drinks
References
Alcoholic drinks
Distilled drinks | Geist (liquor) | [
"Chemistry"
] | 441 | [
"Distillation",
"Distilled drinks"
] |
69,746,055 | https://en.wikipedia.org/wiki/Precociality%20and%20altriciality | Precocial species in birds and mammals are those in which the young are relatively mature and mobile from the moment of birth or hatching. They are normally nidifugous, meaning that they leave the nest shortly after birth or hatching. Altricial species are those in which the young are underdeveloped at the time of birth, but with the aid of their parents mature after birth. These categories form a continuum, without distinct gaps between them.
In fish, this often refers to the presence or absence of a stomach: precocial larvae have one at the onset of first feeding whereas altricial fish do not. Depending on the species, the larvae may develop a functional stomach during metamorphosis (gastric) or remain stomachless (agastric).
Precociality
Precocial young have open eyes, hair or down, large brains, and are immediately mobile and somewhat able to flee from or defend themselves against predators. For example, with ground-nesting birds such as ducks or turkeys, the young are ready to leave the nest in one or two days. Among mammals, most ungulates are precocial, being able to walk almost immediately after birth.
Etymology
The word "precocial" is derived from the Latin root praecox, the same root as in precocious, meaning early maturity.
Superprecociality
Extremely precocial species are called "superprecocial". Examples are the megapode birds, which have full-flight feathers at hatching and which, in some species, can fly on the same day. Enantiornithes and pterosaurs were also capable of flight soon after hatching.
Another example is the blue wildebeest, the calves of which can stand within an average of six minutes from birth and walk within thirty minutes; they can outrun a hyena within a day. Such behavior gives them an advantage over other herbivore species and they are 100 times more abundant in the Serengeti ecosystem than hartebeests, their closest taxonomic relative. Hartebeest calves are not as precocial as wildebeest calves and take up to thirty minutes or more before they stand, and as long as forty-five minutes before they can follow their mothers for short distances. They are unable to keep up with their mothers until they are more than a week old.
Black mambas are highly precocial; as hatchlings, they are fully independent, and are capable of hunting prey the size of a small rat.
Phylogeny
Precociality is thought to be ancestral in birds. Thus, altricial birds tend to be found in the most derived groups. There is some evidence for precociality in protobirds and troodontids. Enantiornithes at least were superprecocial in a way similar to that of megapodes, being able to fly soon after birth. It has been speculated that superprecociality prevented enantiornithines from acquiring specialized toe anatomy seen in modern altricial birds.
Altriciality
In birds and mammals altricial species are those whose newly hatched or born young are relatively immobile, lack hair or down, are not able to obtain food on their own, and must be cared for by adults; closed eyes are common, though not ubiquitous. Altricial young are born helpless and require care for a length of time. Altricial birds include hawks, herons, woodpeckers, owls, cuckoos and most passerines. Among mammals, marsupials and most rodents are altricial. Domestic cats, dogs, and primates, such as humans, are some of the best-known altricial organisms. For example, newborn domestic cats cannot see, hear, maintain their own body temperature, or gag, and require external stimulation in order to defecate and urinate. The giant panda is notably the largest placental mammal to have altricial, hairless young upon birth. The larval stage of insect development is considered by some to be a form of altricial development, but it more accurately depicts, especially amongst eusocial animals, an independent phase of development, as the larvae of bees, ants, and many arachnids are completely physically different from their developed forms, and the pre-pupal stages of insect life might be regarded as equivalent to vertebrate embryonic development.
Etymology
The word “altriciality” is derived from the Latin root alere, meaning "to nurse, to rear, or to nourish", and indicates the need for young to be fed and taken care of for a long duration.
Differences
The span between precocial and altricial species is particularly broad in the biology of birds. Precocial birds hatch with their eyes open and are covered with downy feathers that are soon replaced by adult-type feathers. Birds of this kind can also swim and run much sooner after hatching than altricial young, such as songbirds. Very precocial birds can be ready to leave the nest in a short period of time following hatching (e.g. 24 hours). Many precocial chicks are not independent in thermoregulation (the ability to regulate their body temperatures), and they depend on the attending parent(s) to brood them with body heat for a short time. Precocial birds find their own food, sometimes with help or instruction from their parents. Examples of precocial birds include the domestic chicken, many species of ducks and geese, waders, rails, and the hoatzin.
Precocial birds can provide protein-rich eggs and thus their young hatch in the fledgling stage – able to protect themselves from predators and the females have less post-natal involvement. Altricial birds are less able to contribute nutrients in the pre-natal stage; their eggs are smaller and their young are still in need of much attention and protection from predators. This may be related to r/K selection; however, this association fails in some cases.
In birds, altricial young usually grow faster than precocial young. This is hypothesized to occur so that exposure to predators during the nestling stage of development can be minimized.
In the case of mammals, it has been suggested that large, hearty adult body sizes favor the production of large, precocious young, which develop with a longer gestation period. Large young may be associated with migratory behavior, extended reproductive period, and reduced litter size. It may be that altricial strategies in mammals, in contrast, develop in species with less migratory and more territorial lifestyles, such as Carnivorans, the mothers of which are capable of bearing a fetus in the early stages of development and focusing closely and personally upon its raising, as opposed to precocial animals which provide their youths with a bare minimum of aid and otherwise leave them to instinct.
Human children, and those of other primates, exemplify a unique combination of altricial and precocial development. Infants are born with minimal eyesight, compact and fleshy bodies, and "fresh" features (thinner skin, small noses and ears, and scarce hair if any). However, this stage is only brief amongst primates; their offspring soon develop stronger bones, grow in spurts, and quickly mature in features. This unique growth pattern allows for the hasty adaptivity of most simians, as anything learned by children in between their infancy and adolescence is memorized as instinct; this pattern is also in contrast to more prominently altricial mammals, such as many rodents, which remain largely immobile and undeveloped until grown to near the stature of their parents.
Terminology
In birds, the terms Aves altrices and Aves precoces were introduced by Carl Jakob Sundevall (1836), and the terms nidifugous and nidicolous by Lorenz Oken in 1816. The two classifications were considered identical in early times, but the meanings are slightly different, in that "altricial" and "precocial" refer to developmental stages, while "nidifugous" and "nidicolous" refer to leaving or staying at the nest, respectively.
See also
Parental investment
Precocious puberty
References
Bibliography
External links
The altricial-precocial spectrum in birds
Animal developmental biology
Bird breeding
Developmental biology | Precociality and altriciality | [
"Biology"
] | 1,730 | [
"Behavior",
"Developmental biology",
"Reproduction"
] |
69,746,280 | https://en.wikipedia.org/wiki/Apennine%20Colossus | The Apennine Colossus () is a stone statue, approximately 11 meters high, in the estate of the Villa Demidoff in Vaglia, Tuscany, Italy. Giambologna (Flemish sculptor Jean de Boulogne) created the colossal figure, a personification of the Apennine mountains, in the late 1580s. It was constructed on the grounds of the Villa di Pratolino, a Renaissance villa that fell into disrepair and was replaced by the Villa Demidoff in the 1800s.
Description
The colossus is about high and is meant as a personification of the Apennine Mountains. It was the water source for the Pratolino, its fountains and secret water plays. The colossus has the appearance of an elderly man crouched at the shore of a lake and is surrounded by other sculptures depicting mythological themes from Ovid's Metamorphoses including Pegasus, Parnassus or Jupiter. It is presumed that Giambologna was inspired by the description of a mountain-like Atlas in Ovid's Metamorphoses, when he designed the figure of Apennine. Other sources cite the Atlas as described in the Aeneid of the Roman poet Virgil as an inspiration. With his left hand in front of him, the Apennine seems to squeeze the head of a sea monster through whose open mouth water emanates into the pond ahead of the statue. The stone colossus is depicted naked, with stalactites in the thick beard and long hair to show the metamorphosis of man and mountain, blending his body with the surrounding nature, populated by aquatic vegetation. The statue is described to originally have been emerging from its environment like being alive. The giant was able to sweat and weep over a network of water pipes. In the winter season, icicles would cover his body. The work was made of stone and plaster and appearing to be partially covered with moss and lichens.
Within the giant exist a series of chambers and caves on three levels. In the ground floor of the colossus exists a cave containing an octagonal fountain dedicated to the Greek goddess Thetys. The Italian painter Jacopo Ligozzi adorned the Grotto de Thetys with frescos of villages from the Mediterranean coast of Tuscany in 1586. In other chambers mining scenes based on the book De re metallica by the mineralogist Georgius Agricola were to be seen. In the giant's upper floor is a chamber big enough for a small orchestra and in the head a small chamber holds a fireplace out of which the smoke would escape through his nostrils. The chamber in the head had slits in the ears and the eyes. Francesco I de Medici, Grand Duke of Tuscany, enjoyed fishing while sitting in the head chamber, throwing the fishing line through one of the eye slits. At night the chamber was illuminated with torches, following which the eyes appeared to glow in the dark. Initially, the back of the Colossus was protected by a structure resembling a cave, as seen on an etching by Stefano della Bella. As Giambologna was an admirer of the Italian sculptor Michelangelo the cave-like structure was also compared with Michelangelo's style of the non-finito. On top of it, there was a terrace. The cave-resembling structure was demolished around 1690 by the sculptor Giovan Battista Foggini, who also built a statue of a dragon to adorn the back of the colossus. The dragon was described to have been a fountain, but it is assumed the dragon's belly was transformed into a fireplace while the dragon's neck and head had the function of its chimney. In 1876, the Italian sculptor Rinaldo Barbetti renovated the statue.
Location and ownership
The Pratolino is located about north of Florence at the foot of the Apennine mountain range. In it, there is a rectangular square called the Prato del Appennino, situated in front of the colossus.
After Francesco de' Medici's death in 1587 and that of his wife Bianca Capello the next day, the villa and its surroundings fell into decay. The Villa di Pratolino was demolished in 1822 and in 1872, the heirs of Leopold II, Grand Duke of Tuscany, sold the estate to the Demidoff family who built their own villa on it. In 1981, the Villa Demidoff was purchased by the Province of Florence and today the park and its giant are accessible to the public.
Gallery
References
External links
Medici villas
History of Florence
Sculptures by Giambologna
Colossal statues
1580s sculptures
Sculptures of dragons | Apennine Colossus | [
"Physics",
"Mathematics"
] | 943 | [
"Quantity",
"Colossal statues",
"Physical quantities",
"Size"
] |
69,746,652 | https://en.wikipedia.org/wiki/Merry%20Lindsey | Merry L. Lindsey is an American cardiac physiologist. In 2022 she was named the Dean of the School of Graduate Studies at Meharry Medical College. In 2019 she was named the Stokes-Shackleford Professor and Chair of the University of Nebraska Medical Center Department of Cellular and Integrative Physiology and the director of the Center for Heart and Vascular Research. In 2021, Lindsey was appointed editor-in-chief of the American Journal of Physiology. Heart and Circulatory Physiology.
Early life and education
Lindsey was born Stuart, Florida in 1970 and raised in South Florida, where she attended South Fork High School. Following high school, Lindsey earned her undergraduate degree in biology from Boston University and her PhD in cardiovascular sciences from Baylor College of Medicine.
Career
Upon completing her PhD, Lindsey worked at the Medical University of South Carolina as an assistant professor before joining the faculty at the University of Texas Health Science Center. In 2019, she left the Mississippi Center for Heart Research to accept an appointment as the Stokes-Shackleford Professor and Chair of the Department of Cellular and Integrative Physiology at the University of Nebraska Medical Center. Upon joining the department, Lindsey also became the founding director of the Center for Heart and Vascular Research. She joined Meharry Medical College as the dean of the School of Graduate Studies and Research.
In 2021, Lindsey was appointed editor-in-chief of the American Journal of Physiology. Heart and Circulatory Physiology, a journal published by the American Physiological Society. She received the Vincenzo Panagia Distinguished Lecture Award from the Institute of Cardiovascular Sciences at St-Boniface Hospital Research in 2021, and the Distinguished Investigator Award from the British Society for Cardiovascular Research in 2022.
References
External links
Living people
Medical journal editors
Boston University College of Arts and Sciences alumni
Baylor College of Medicine alumni
University of Nebraska Medical Center faculty
Medical University of South Carolina faculty
Physiology
Physiologists
Cardiovascular physiology
Cardiovascular researchers
Proteomics
University of Texas Health Science Center at San Antonio faculty
Year of birth missing (living people) | Merry Lindsey | [
"Biology"
] | 410 | [
"Physiology"
] |
69,748,347 | https://en.wikipedia.org/wiki/3%2C5-Difluoro-4-hydroxybenzylidene%20imidazolinone | 3,5-Difluoro-4-hydroxybenzylidene imidazolinone or DFHBI is an imidazolinone fluorophore used in various biochemical studies. The benzene ring of DFHBI can freely rotate around the single bond but when it is fixed in planar conformation, DFHBI fluoresces. It is a synthetic analog of the GFP fluorophore.
References
Imidazolinones
Fluoroarenes
Phenols | 3,5-Difluoro-4-hydroxybenzylidene imidazolinone | [
"Chemistry"
] | 109 | [
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
69,748,680 | https://en.wikipedia.org/wiki/Budapest%20Tram%20Line%201 | The Tram Line 1 of Budapest (in Hungarian: budapesti 1-es jelzésű villamosvonal) is a line operated by BKK Zrt., the transport authority of Budapest. It was commissioned in 1984 between Bécsi út / Vörösvári út and Lehel utca. It then has numerous extension phases, which in 2000 make it possible to connect north to south of Pest along the great ring road (Róbert Károly körút - Hungária körút - Könyves Kálmán körút), between the Árpád híd and Rákóczi híd bridges. Since March 2015, the line also crosses the Danube in its southern part, and it was further extended in 2019 to Kelenföld vasútállomás M. It now runs between Bécsi út / Vörösvári út and Kelenföld vasútállomás.
Line and Stations
References
Budapest
Public transport in Budapest | Budapest Tram Line 1 | [
"Physics"
] | 191 | [
"Physical systems",
"Transport",
"Transport stubs"
] |
78,632,337 | https://en.wikipedia.org/wiki/NGC%207637 | NGC7637 is a spiral galaxy in the constellation of Octans. Its velocity with respect to the cosmic microwave background is 3711 ± 3km/s, which corresponds to a Hubble distance of . It was discovered by British astronomer John Herschel on 17 October 1835.
Supernovae
Three supernovae have been observed in NGC 7637:
SN1992ao (typeII, mag. 17) was discovered by Robert H. McNaught on 28 July 1992.
SN2012ah (typeIa, mag. 14.8) was discovered by Stuart Parker on 21 February 2012.
SN2022iwt (type II, mag. 16.825) was discovered by ATLAS on 29 April 2022.
See also
List of NGC objects (7001–7840)
References
External links
7637
071440
23226-8211
012- G 001
Octans
18351017
Discoveries by John Herschel
Unbarred spiral galaxies | NGC 7637 | [
"Astronomy"
] | 199 | [
"Octans",
"Constellations"
] |
78,632,714 | https://en.wikipedia.org/wiki/Solar%20Data%20Analysis%20Center | NASA's Solar Data Analysis Center (SDAC) is a data center and repository at NASA/GSFC, responsible for managing and archiving data from scientific heliophysics missions. The center is a major distribution hub for solar images from the SDO and other solar space missions such as SOHO, Hinode and STEREO, and serves as an access point for the Virtual Solar Observatory and many other heliophysics and solar physics resources.
References
Space technology research institutes
Data centers | Solar Data Analysis Center | [
"Technology"
] | 97 | [
"Data centers",
"Computers"
] |
78,633,661 | https://en.wikipedia.org/wiki/Vertical%20circle%20%28instrument%29 | The vertical circle is an optical instrument used to measure angles in astronomy, which name is derived from the mathematical concept of the vertical circle from spherical geometry. It is a device for measuring astronomical angles, which can be rotated in altitude and azimuth. It consists of a telescope (in astronomical geodesy occasionally also with a reflecting telescope), which is mounted on a horizontal tilting axis and is supported by a stable altazimuth mount. It is similar in design to the meridian circle, but the latter only has a horizontal tilting axis without the means to change azimuth. The angular movements around the tilting and standing axes are measured with large, finely divided circles and a reading microscope.
Instruments like this were more common in 19th century observatories and were important for locating and recording coordinates in the cosmos, and observatories often had various other instruments for certain functions as well as advanced clocks of the period. The popularly known example in the observatories, was the Great Refractors which became larger and larger and came to have a dominating effect to the point that observatories were moved simply to have better conditions for their biggest telescope, in the modern style where observatories often have one instrument only in a remote location on the Earth or even in outer space. However, in the 19th century it was more basic with observatories often making recording of coordinates of different items and to determine the shape of the Earth and times.
See also
Meridian circle
Equatorial telescope
Comet seeker
References
Astrometry | Vertical circle (instrument) | [
"Astronomy"
] | 309 | [
"Astrometry",
"Astronomical sub-disciplines"
] |
78,633,817 | https://en.wikipedia.org/wiki/Peronospora%20violacea | Peronospora violacea is a floricolous downy mildew which infects plants in the Caprifoliaceae. It has been reported from hosts in the genera Dipsacus, Knautia, Lomelosia, Scabiosa, and Succisa.
It produces conidiophores on the petals and styles of the host, oospores inside the petal and style tissue, and suppresses the development of the anthers. Infection is systemic, with hyphae produced in the xylem of the host rhizomes and stems.
In infected plants of Succisa pratensis the flowers have longer, pinker petals on which the conidophores are produced. However, other authors report that on the same host it causes the host corollas to be brownish and dead-looking.
Gallery
References
Peronosporales
Plant pathogens and diseases | Peronospora violacea | [
"Biology"
] | 188 | [
"Plant pathogens and diseases",
"Plants"
] |
78,634,018 | https://en.wikipedia.org/wiki/Andreas%20Kordellas | Andreas Kordellas (30 November 1836 – 1909) was a Greek mineralogist and mining engineer.
Biography
On 30 November 1836, Andreas Kordellas was born in İzmir (known in Greek as Smyrna), then under the Ottoman Empire. His father was a merchant originally from Ampelakia on the island of Salamis. In 1852, Kordellas began study at an industrial school in Zittau, Saxony; in 1855, he transferred to the Bergakademie Freiberg, but also took classes in philosophy at the University of Bonn and in mining in Liège, Belgium. He graduated in 1858.
Kordellas briefly returned to Smyrna in 1860, but left for Athens in the same year. There, he found employment at the state Ministry of Finance. He drafted mining legislation alongside Panayiotis G. Vouyoukas and Ioannis Soutsos. He was appointed the foreman of the Naxos emery mines from 1861 to 1863. He was also employed to manage water supply for the city of Athens. In 1865, he left the Ministry of Finance to become the Director of Works for a private mining company, Hilarion Roux & Cie; the company was the first modern enterprise to exploit the ancient Mines of Laurion. He had investigated the mines in December 1860 while under state employ and wrote a report on the state of the mines in the region, seeing great promise in the re-smelting of slag at the site. He simultaneously served as the director of works for another mining company, I. V. Serpieris & Co., from 1865 to 1873. In 1887 he became the director of the Greek Metal Works Company of Lavrion.
Kordellas published various papers on mineralogy and geology. He was a member of the Greek organizing committee for the 1889 Exposition Universelle in Paris, France, for which he wrote a paper advertising Greece's mineral wealth. He was a professor of mineralogy and geology at the Hellenic Military Academy from 1882 to 1894, and the inaugural president of the Hellenic Polytechnic Association from 1899. He died in Athens in 1909. During the 1990s, archaeologists named an ancient ergasterion (silver processing workshop) found at Laurion the Kordellas Ergasterion in his honor.
References
Works cited
People from İzmir
1909 deaths
Greek geologists
Freiberg University of Mining and Technology alumni
University of Bonn alumni
Mining engineers
Mineralogists
1836 births | Andreas Kordellas | [
"Engineering"
] | 501 | [
"Mining engineering",
"Mining engineers"
] |
78,634,614 | https://en.wikipedia.org/wiki/Le%20Minerale | Le Minerale is a brand of bottled drinking water from Indonesia produced by PT Tirta Fresindo Jaya, a subsidiary of Mayora Group. The product was first launched in 2015.
Le Minerale competes with several other bottled drinking water brands in the Indonesian market, particularly Aqua, the leading brand in the industry. The company has also expanded its presence to international markets, including the Philippines, Singapore, Brunei, and Malaysia.
See also
Kopiko (brand)
References
Mayora Indah brands
Bottled water brands
Indonesian brands
Indonesian drinks
Mineral water
Products introduced in 2015 | Le Minerale | [
"Chemistry"
] | 115 | [
"Mineral water"
] |
78,635,504 | https://en.wikipedia.org/wiki/15.ai | 15.ai was a free non-commercial web application that used artificial intelligence to generate text-to-speech voices of fictional characters from popular media. Created by an artificial intelligence researcher known as 15 during their time at the Massachusetts Institute of Technology, the application allowed users to make characters from video games, television shows, and movies speak custom text with emotional inflections faster than real-time. The platform was notable for its ability to generate convincing voice output using minimal training data—the name "15.ai" referenced the creator's claim that a voice could be cloned with just 15 seconds of audio. It was an early example of an application of generative artificial intelligence during the initial stages of the AI boom.
Launched in March 2020, 15.ai gained widespread attention in early 2021 when it went viral on social media platforms like YouTube and Twitter, and quickly became popular among Internet fandoms, including the My Little Pony: Friendship Is Magic, Team Fortress 2, and SpongeBob SquarePants fandoms. The service distinguished itself through its support for emotional context in speech generation through emojis and precise pronunciation control through phonetic transcriptions. 15.ai is credited as the first mainstream platform to popularize AI voice cloning (audio deepfakes) in memes and content creation.
15.ai received varied responses from the voice acting community and broader public. Voice actors and industry professionals debated the technology's merits for fan creativity versus its potential impact on the profession, particularly following controversies over unauthorized commercial use. While many critics praised the website's accessibility and emotional control, they also noted technical limitations in areas like prosody options and language support. The technology sparked discussions about ethical implications, including concerns about reduction of employment opportunities for voice actors, voice-related fraud, and misuse in explicit content, though 15.ai maintained strict policies against replicating real people's voices.
15.ai's approach to data-efficient voice synthesis and emotional expression was influential in subsequent developments in AI text-to-speech technology. In January 2022, Voiceverse NFT sparked controversy when it was discovered that the company, which had partnered with voice actor Troy Baker, had misappropriated 15.ai's work for their own platform. The service was ultimately taken offline in September 2022. Its shutdown led to the emergence of various commercial alternatives in subsequent years.
History
Background
The field of artificial speech synthesis underwent a significant transformation with the introduction of deep learning approaches. In 2016, DeepMind's publication of the seminal paper WaveNet: A Generative Model for Raw Audio marked a pivotal shift toward neural network-based speech synthesis, demonstrating unprecedented audio quality through dilated causal convolutions operating directly on raw audio waveforms at 16,000 samples per second, modeling the conditional probability distribution of each audio sample given all previous ones. Previously, concatenative synthesis—which worked by stitching together pre-recorded segments of human speech—was the predominant method for generating artificial speech, but it often produced robotic-sounding results with noticeable artifacts at the segment boundaries. Two years later, this was followed by Google AI's Tacotron in 2018, which demonstrated that neural networks could produce highly natural speech synthesis but required substantial training data—typically tens of hours of audio—to achieve acceptable quality. When trained on smaller datasets, such as 2 hours of speech, the output quality degraded while still being able to maintain intelligible speech, and with just 24 minutes of training data, Tacotron failed to produce intelligible speech. The same year saw the emergence of HiFi-GAN, a generative adversarial network (GAN)-based vocoder that improved the efficiency of waveform generation while producing high-fidelity speech, followed by Glow-TTS, which introduced a flow-based approach that allowed for both fast inference and voice style transfer capabilities. Chinese tech companies also made significant contributions to the field, with Baidu and ByteDance developing proprietary text-to-speech frameworks that further advanced the state of the art, though specific technical details of their implementations remained largely undisclosed.
Development, release, and operation
15.ai was conceived in 2016 as a research project in deep learning speech synthesis by a developer known as "15" (at the age of 18) during their freshman year at the Massachusetts Institute of Technology (MIT) as part of MIT's Undergraduate Research Opportunities Program (UROP). The developer was inspired by DeepMind's WaveNet paper, with development continuing through their studies as Google AI released Tacotron the following year. By 2019, the developer had demonstrated at MIT their ability to replicate WaveNet and Tacotron's results using 75% less training data than previously required. The name 15 is a reference to the creator's claim that a voice can be cloned with as little as 15 seconds of data.
The developer had originally planned to pursue a doctorate based on their undergraduate research, but opted to work in the tech industry instead after their startup was accepted into the Y Combinator accelerator in 2019. After their departure in early 2020, the developer returned to their voice synthesis research, implementing it as a web application. According to the developer, instead of using conventional voice datasets like LJSpeech that contained simple, monotone recordings, they sought out more challenging voice samples that could demonstrate the model's ability to handle complex speech patterns and emotional undertones. The Pony Preservation Project—a fan initiative originating from /mlp/, 4chan's My Little Pony board, that had compiled voice clips from My Little Pony: Friendship Is Magic—played a crucial role in the implementation. The project's contributors had manually trimmed, denoised, transcribed, and emotion-tagged every line from the show. This dataset provided ideal training material for 15.ai's deep learning model.
15.ai was released in March 2020 with a limited selection of characters, including those from My Little Pony: Friendship Is Magic and Team Fortress 2. More voices were added to the website in the following months. A significant technical advancement came in late 2020 with the implementation of a multi-speaker embedding in the deep neural network, enabling simultaneous training of multiple voices rather than requiring individual models for each character voice. This not only allowed rapid expansion from eight to over fifty character voices, but also let the model recognize common emotional patterns across characters, even when certain emotions were missing from some characters' training data.
In early 2021, the application went viral on Twitter and YouTube, with people generating skits, memes, and fan content using voices from popular games and shows that have accumulated millions of views on social media. Content creators, YouTubers, and TikTokers have also used 15.ai as part of their videos as voiceovers. At its peak, the platform incurred operational costs of per month from AWS infrastructure needed to handle millions of daily voice generations; despite receiving offers from companies to acquire 15.ai and its underlying technology, the website remained independent and was funded out of the personal previous startup earnings of the developer—then aged 23 at the time.
Voiceverse NFT controversy
On January 14, 2022, a controversy ensued after it was discovered that Voiceverse NFT, a company that video game and anime dub voice actor Troy Baker had announced his partnership with, had misappropriated voice lines generated from 15.ai as part of their marketing campaign. This came shortly after 15.ai's developer had explicitly stated in December 2021 that they had no interest in incorporating NFTs into their work. Log files showed that Voiceverse had generated audio of characters from My Little Pony: Friendship Is Magic using 15.ai, pitched them up to make them sound unrecognizable from the original voices to market their own platform—in violation of 15.ai's terms of service.
Voiceverse claimed that someone in their marketing team used the voice without properly crediting 15.ai; in response, 15 tweeted "Go fuck yourself," which went viral, amassing hundreds of thousands of retweets and likes on Twitter in support of the developer. Following continued backlash and the plagiarism revelation, Baker acknowledged that his original announcement tweet ending with "You can hate. Or you can create. What'll it be?" may have been "antagonistic," and on January 31, 2022, announced he would discontinue his partnership with Voiceverse.
Inactivity
In September 2022, 15.ai was taken offline due to legal issues surrounding artificial intelligence and copyright. The creator has suggested a potential future version that would better address copyright concerns from the outset, though the website remains inactive as of 2025.
Features
The platform was non-commercial, and operated without requiring user registration or accounts. Users generated speech by inputting text and selecting a character voice, with optional parameters for emotional contextualizers and phonetic transcriptions. Each request produced three audio variations with distinct emotional deliveries sorted by confidence score. Characters available included multiple characters from Team Fortress 2 and My Little Pony: Friendship Is Magic; GLaDOS, Wheatley, and the Sentry Turret from the Portal series; SpongeBob SquarePants; Kyu Sugardust from HuniePop, Rise Kujikawa from Persona 4; Daria Morgendorffer and Jane Lane from Daria; Carl Brutananadilewski from Aqua Teen Hunger Force; Steven Universe from Steven Universe; Sans from Undertale; Madeline and multiple characters from Celeste; the Tenth Doctor Who; the Narrator from The Stanley Parable; and HAL 9000 from 2001: A Space Odyssey. Out of the over fifty voices available, thirty were of characters from My Little Pony: Friendship Is Magic. Certain "silent" characters like Chell and Gordon Freeman were able to be selected as a joke, and would emit silent audio files when any text was submitted.
The deep learning model's nondeterministic properties produced variations in speech output, creating different intonations with each generation, similar to how voice actors produce different takes. 15.ai introduced the concept of emotional contextualizers, which allowed users to specify the emotional tone of generated speech through guiding phrases. The emotional contextualizer functionality utilized DeepMoji, a sentiment analysis neural network developed at the MIT Media Lab. Introduced in 2017, DeepMoji processed emoji embeddings from 1.2 billion Twitter posts (from 2013 to 2017) to analyze emotional content. Testing showed the system could identify emotional elements, including sarcasm, more accurately than human evaluators. If an input into 15.ai contained additional context (specified by a vertical bar), the additional context following the bar would be used as the emotional contextualizer. For example, if the input was Today is a great day!|I'm very sad., the selected character would speak the sentence "Today is a great day!" in the emotion one would expect from someone saying the sentence "I'm very sad."
The application used pronunciation data from Oxford Dictionaries API, Wiktionary, and CMU Pronouncing Dictionary, the last of which is based on ARPABET, a set of English phonetic transcriptions originally developed by the Advanced Research Projects Agency in the 1970s. For modern and Internet-specific terminology, the system incorporated pronunciation data from user-generated content websites, including Reddit, Urban Dictionary, 4chan, and Google. Inputting ARPABET transcriptions was also supported, allowing users to correct mispronunciations or specify the desired pronunciation between heteronyms—words that have the same spelling but have different pronunciations. Users could invoke ARPABET transcriptions by enclosing the phoneme string in curly braces within the input box (for example, {AA1 R P AH0 B EH2 T} to specify the pronunciation of the word "ARPABET" ( ). The interface displayed parsed words with color-coding to indicate pronunciation certainty: green for words found in the existing pronunciation lookup table, blue for manually entered ARPABET pronunciations, and red for words where the pronunciation had to be algorithmically predicted.
Later versions of 15.ai introduced multi-speaker capabilities. Rather than training separate models for each voice, 15.ai used a unified model that learned multiple voices simultaneously through speaker embeddings–learned numerical representations that captured each character's unique vocal characteristics. Along with the emotional context conferred by DeepMoji, this neural network architecture enabled the model to learn shared patterns across different characters' emotional expressions and speaking styles, even when individual characters lacked examples of certain emotional contexts in their training data.
The interface included technical metrics and graphs, which, according to the developer, served to highlight the research aspect of the website. As of version v23, released in September 2021, the interface displayed comprehensive model analysis information, including word parsing results and emotional analysis data. The flow and generative adversarial network (GAN) hybrid vocoder and denoiser, introduced in an earlier version, was streamlined to remove manual parameter inputs.
Reception
Critical reception
Critics described 15.ai as easy to use and generally able to convincingly replicate character voices, with occasional mixed results. Natalie Clayton of PC Gamer wrote that SpongeBob SquarePants' voice was replicated well, but noted challenges in mimicking the Narrator from the The Stanley Parable: "the algorithm simply can't capture Kevan Brighting's whimsically droll intonation." Zack Zwiezen of Kotaku reported that "[his] girlfriend was convinced it was a new voice line from GLaDOS' voice actor, Ellen McLain". Rionaldi Chandraseta of AI newsletter Towards Data Science observed that "characters with large training data produce more natural dialogues with clearer inflections and pauses between words, especially for longer sentences." Taiwanese newspaper United Daily News also highlighted 15.ai's ability to recreate GLaDOS's mechanical voice, alongside its diverse range of character voice options. Yahoo! News Taiwan reported that "GLaDOS in Portal can pronounce lines nearly perfectly", but also criticized that "there are still many imperfections, such as word limit and tone control, which are still a little weird in some words." Chris Button of AI newsletter Byteside called the ability to clone a voice with only 15 seconds of data "freaky" but also called tech behind it "impressive". The platform's voice generation capabilities were regularly featured on Equestria Daily, a fandom news site dedicated to the show My Little Pony: Friendship Is Magic and its other generations, with documented updates, fan creations, and additions of new character voices. In a post introducing new character additions to 15.ai, Equestria Daily'''s founder Shaun Scotellaro—also known by his online moniker "Sethisto"—wrote that "some of [the voices] aren't great due to the lack of samples to draw from, but many are really impressive still anyway."
Multiple other critics also found the word count limit, prosody options, and English-only nature of the application as not entirely satisfactory. Peter Paltridge of anime and superhero news outlet Anime Superhero News opined that "voice synthesis has evolved to the point where the more expensive efforts are nearly indistinguishable from actual human speech," but also noted that "In some ways, SAM is still more advanced than this. It was possible to affect SAM’s inflections by using special characters, as well as change his pitch at will. With 15.ai, you’re at the mercy of whatever random inflections you get." Conversely, Lauren Morton of Rock, Paper, Shotgun praised the depth of pronunciation control—"if you're willing to get into the nitty gritty of it". Similarly, Eugenio Moto of Spanish news website Qore.com wrote that "the most experienced [users] can change parameters like the stress or the tone." Takayuki Furushima of Den Fami Nico Gamer highlighted the "smooth pronunciations", and Yuki Kurosawa of AUTOMATON noted its "rich emotional expression" as a major feature; both Japanese authors noted the lack of Japanese-language support. Renan do Prado of the Brazilian gaming news outlet Arkade and José Villalobos of Spanish gaming outlet LaPS4 pointed out that while users could create amusing results in Portuguese and Spanish respectively, the generation performed best in English. Chinese gaming news outlet GamerSky called the app "interesting", but also criticized the word count limit of the text and the lack of intonations. South Korean video game outlet Zuntata wrote that "the surprising thing about 15.ai is that [for some characters], there's only about 30 seconds of data, but it achieves pronunciation accuracy close to 100%". Machine learning professor Yongqiang Li wrote in his blog that he was surprised to see that the application was free.
Reactions from voice actors of featured characters
Some voice actors whose characters appeared on 15.ai have publicly shared their thoughts about the platform. In a 2021 interview on video game voice acting podcast The VŌC, John Patrick Lowrie—who voices the Sniper in Team Fortress 2—explained that he had discovered 15.ai when a prospective intern showed him a skit she had created using AI-generated voices of the Sniper and the Spy from Team Fortress 2. Lowrie commented:
He drew an analogy to synthesized music, adding:
In a 2021 live broadcast on his Twitch channel, Nathan Vetterlein—the voice actor of the Scout from Team Fortress 2—listened to an AI recreation of his character's voice. He described the impression as "interesting" and noted that "there's some stuff in there."
Ethical concerns
Other voice actors had mixed reactions to 15.ai's capabilities. While some industry professionals acknowledged the technical innovation, others raised concerns about the technology's implications for their profession. When voice actor Troy Baker announced his partnership with Voiceverse NFT, which had misappropriated 15.ai's technology, it sparked widespread controversy within the voice acting industry. Critics raised concerns about automated voice acting's potential reduction of employment opportunities for voice actors, risk of voice impersonation, and potential misuse in explicit content. The controversy surrounding Voiceverse NFT and subsequent discussions highlighted broader industry concerns about AI voice synthesis technology.
While 15.ai limited its scope to fictional characters and did not reproduce voices of real people or celebrities, computer scientist Andrew Ng noted that similar technology could be used to do so, including for nefarious purposes. In his 2020 assessment of 15.ai, he wrote:
While discussing potential risks, he added:
Legacy
15.ai was an early pioneer of audio deepfakes, leading to the emergence of AI speech synthesis-based memes during the initial stages of the AI boom in 2020. 15.ai is credited as the first mainstream platform to popularize AI voice cloning in Internet memes and content creation, particularly through its ability to generate convincing character voices in real-time without requiring extensive technical expertise. The platform's impact was especially notable in fan communities, including the My Little Pony: Friendship Is Magic, Portal, Team Fortress 2, and SpongeBob SquarePants fandoms, where it enabled the creation of viral content that garnered millions of views across social media platforms like Twitter and YouTube. Team Fortress 2 content creators also used the platform to produce both short-form memes and complex narrative animations using Source Filmmaker. Fan creations included skits and new fan animations, crossover content—such as Game Informer writer Liana Ruppert's demonstration combining Portal and Mass Effect dialogue in her coverage of the platform—recreations of viral videos (including the infamous Big Bill Hell's Cars car dealership parody), adaptations of fanfiction using AI-generated character voices, music videos and new musical compositions—such as the explicit Pony Zone series—and content where characters recited sea shanties. Some fan creations gained mainstream attention, such as a viral edit replacing Donald Trump's cameo in Home Alone 2: Lost in New York'' with the Heavy Weapons Guy's AI-generated voice, which was featured on a daytime CNN segment in January 2021. Some users integrated 15.ai's voice synthesis with VoiceAttack, a voice command software, to create personal assistants.
Its influence has been noted in the years after it became defunct, with several commercial alternatives emerging to fill the void, such as ElevenLabs and Speechify. Contemporary generative voice AI companies have acknowledged 15.ai's pioneering role. Y Combinator startup PlayHT called the debut of 15.ai "a breakthrough in the field of text-to-speech (TTS) and speech synthesis". Cliff Weitzman, the founder and CEO of Speechify, credited 15.ai for "making AI voice cloning popular for content creation by being the first [...] to feature popular existing characters from fandoms". Mati Staniszewski, co-founder and CEO of ElevenLabs, wrote that 15.ai was transformative in the field of AI text-to-speech.
Prior to its shutdown, 15.ai established several technical precedents that influenced subsequent developments in AI voice synthesis. Its integration of DeepMoji for emotional analysis demonstrated the viability of incorporating sentiment-aware speech generation, while its support for ARPABET phonetic transcriptions set a standard for precise pronunciation control in public-facing voice synthesis tools. The platform's unified multi-speaker model, which enabled simultaneous training of diverse character voices, proved particularly influential. This approach allowed the system to recognize emotional patterns across different voices even when certain emotions were absent from individual character training sets; for example, if one character had examples of joyful speech but no angry examples, while another had angry but no joyful samples, the system could learn to generate both emotions for both characters by understanding the common patterns of how emotions affect speech.
15.ai also made a key contribution in reducing training data requirements for speech synthesis. Earlier systems like Google AI's Tacotron and Microsoft Research's FastSpeech required tens of hours of audio to produce acceptable results and failed to generate intelligible speech with less than 24 minutes of training data. In contrast, 15.ai demonstrated the ability to generate speech with substantially less training data—specifically, the name "15.ai" refers to the creator's claim that a voice could be cloned with just 15 seconds of data. This approach to data efficiency influenced subsequent developments in AI voice synthesis technology, as the 15-second benchmark became a reference point for subsequent voice synthesis systems. The original claim that only 15 seconds of data is required to clone a human's voice was corroborated by OpenAI in 2024.
See also
AI boom
Character.ai
Deepfake
Ethics of artificial intelligence
WaveNet
My Little Pony: Friendship Is Magic fandom
Explanatory footnotes
References
Notes
Works cited
External links
Archived frontend
Internet properties established in 2020
Applications of artificial intelligence
2020 software
2020 in Internet culture
2020s in Internet culture
2020s fads and trends
Web applications
Speech synthesis
Deep learning software applications
Deepfakes
Generative artificial intelligence
My Little Pony: Friendship Is Magic fandom
Massachusetts Institute of Technology software | 15.ai | [
"Engineering"
] | 4,772 | [
"Artificial intelligence engineering",
"Generative artificial intelligence"
] |
78,636,345 | https://en.wikipedia.org/wiki/NGC%204545 | NGC4545 is a barred spiral galaxy in the constellation of Draco. Its velocity with respect to the cosmic microwave background is , which corresponds to a Hubble distance of . Additionally, 19 non-redshift measurements give a distance of . It was discovered by German-British astronomer William Herschel on 20 March 1790.
NGC 4545 Group
NGC 4545 is the brightest galaxy in a group of galaxies that bears its name. The NGC 4545 group (also known as LGG 295) has at least six members, including NGC 4510, NGC 4512, NGC 4521, UGC 7848, and UGC 7941.
Supernova
One supernova has been observed in NGC 4545: SN1940D (type unknown, mag. 15) was discovered by Josef J. Johnson on 25 July 1940.
See also
List of NGC objects (4001–5000)
References
External links
4545
041838
12323+6348
07747
+11-15-064
Draco (constellation)
17900320
Discoveries by William Herschel
Barred spiral galaxies | NGC 4545 | [
"Astronomy"
] | 221 | [
"Constellations",
"Draco (constellation)"
] |
78,637,776 | https://en.wikipedia.org/wiki/Microbotryum%20succisae | Microbotryum succisae is a smut fungus that infects the devil's-bit scabious, Succisa pratensis. It produces whitish to pale yellow spores in the host plant's anthers.
References
Plant pathogens and diseases
Microbotryales | Microbotryum succisae | [
"Biology"
] | 62 | [
"Plant pathogens and diseases",
"Plants"
] |
78,638,730 | https://en.wikipedia.org/wiki/McN%205707 | Mcn 5707 is a SNDRI agent designated for the treatment of depression. It was developed by Bruce Maryanoff of McNeil (now Johnson & Johnson) in the 1980s.
For related agents, see JNJ-7925476, McN 4612-z, McN-5292, McN-5558 & McN5652.
References
Serotonin–norepinephrine–dopamine reuptake inhibitors
Stimulants
Pyrroloisoquinolines
Drugs developed by Johnson & Johnson
Abandoned drugs
2-Chlorophenyl compounds | McN 5707 | [
"Chemistry"
] | 125 | [
"Drug safety",
"Abandoned drugs"
] |
78,639,376 | https://en.wikipedia.org/wiki/HD%2043317 | HD 43317 is a variable star in the equatorial constellation of Orion, the hunter. It has an apparent visual magnitude of 6.63, which is faint enough to be a challenge to view with the naked eye under good conditions. Based on parallax measurements, it is located at a distance of approximately 1,050 light years from the Sun. It is drifting further away with a heliocentric radial velocity of about 13 km/s. This star is a member of an open cluster designated OCSN 63.
Observations
During 2009–2010, HD 43317 was observed by the CoRoT space telescope during the LRa03 (long run) sequence for asteroseismological purposes. This program lasted for a period of 150.41 days, during which the star was under almost constant observation. After being combined with HARPS data, the star was classified as a hybrid slowly pulsating B-type star and a Beta Cephei variable. Both g (gravity) and p (pressure) mode pulsations were detected. It is spinning rapidly at about half of its critical velocity.
The photometry and spectrometry of HD 43317 showed rotational modulation of regions with temperature or chemical differences. These are an indirect indicator of a magnetic field. In addition, X-ray emission was detected by ROSAT, which also suggests a potential magnetic field. A magnetic field was directly detected with the Téléscope Bernard Lyot during 2012. The longitudinal field strength was found to vary with the rotation period, ranging from to . Modelling of the star's dipolar field found a strength between 1 and . This is strong enough to force uniform rotation in the outer radiative zone of the star.
The CoRoT light curve of the star displays 35 different frequencies, of which 28 are not related to the rotation period. Seismic modeling of the star determined a stellar mass equal to 5.8 times the mass of the Sun. At the core, the central mass fraction of hydrogen is 54%, compared to 70% for a newly formed main sequence star and 0.1% at the end of main sequence lifetime. Spectroscopic analysis shows an effective temperature of around 17,350 in the stellar atmosphere. A refined estimate of the surface magnetic field strength found a value of . The magnetic field near the core has a seismically modelled strength of . HD 43317 is the first main sequence star for which an interior magnetic field strength has been inferred.
This star has an estimated radius of 3.39 times the girth of the Sun, and is radiating 737.5 times the Sun's luminosity. It is about 28.4 million years old.
References
B-type main-sequence stars
Slowly pulsating B-type stars
Beta Cephei variables
Orion (constellation)
2232
Durchmusterung objects
043317
029739 | HD 43317 | [
"Astronomy"
] | 584 | [
"Constellations",
"Orion (constellation)"
] |
78,639,694 | https://en.wikipedia.org/wiki/NGC%204136 | NGC4136 is a barred spiral galaxy in the constellation of Coma Berenices. Its velocity with respect to the cosmic microwave background is , which corresponds to a Hubble distance of . Additionally, seven non-redshift measurements give a distance of . It was discovered by German-British astronomer William Herschel on 13 March 1785.
Morphology
Eskridge, Frogel, and Pogge published a paper in 2002 describing the morphology of 205 closely spaced spiral or lenticular galaxies. The observations were made in the H-band of the infrared and in the B-band (blue). Eskridge and colleagues described NGC 4136 as follows:
NGC 4274 Group
NGC 4136 is a member of the NGC 4274 group (also known as LGG 279) which has at least 19 galaxies, including NGC 4020, NGC 4062, NGC 4173, NGC 4203, NGC 4245, NGC 4251, NGC 4274, NGC 4278, NGC 4283, NGC 4310, NGC 4314, NGC 4359, NGC 4414, NGC 4509, NGC 4525, UGC 7300, and MCG+05-29-066.
Supernova
One supernova has been observed in NGC 4136: SN1941C (type unknown, mag. 16.8) was discovered by Rebecca B. Jones on 16 April 1941.
See also
List of NGC objects (4001–5000)
References
External links
4136
038618
12067+3012
07134
+05-29-025
Coma Berenices
17850313
Discoveries by William Herschel
Barred spiral galaxies | NGC 4136 | [
"Astronomy"
] | 338 | [
"Coma Berenices",
"Constellations"
] |
78,641,015 | https://en.wikipedia.org/wiki/NGC%202672 | NGC2672 is a elliptical galaxy in the constellation of Cancer. Its velocity with respect to the cosmic microwave background is , which corresponds to a Hubble distance of . Additionally, 11 non-redshift measurements give a distance of . It was discovered by German-British astronomer William Herschel on 14 March 1784.
The SIMBAD database lists NGC 2672 as an Active Galaxy Nucleus Candidate, i.e. it has a compact region at the center of a galaxy that emits a significant amount of energy across the electromagnetic spectrum, with characteristics indicating that this luminosity is not produced by the stars.
NGC 2672 is listed with the galaxy NGC 2673 as Holm 99 in Erik Holmberg's A Study of Double and Multiple Galaxies Together with Inquiries into some General Metagalactic Problems, published in 1937. These two galaxies are also listed in Halton Arp's Atlas of Peculiar Galaxies as Arp167, with the description "Comp. galaxy very condensed, has curved plume." Another study indicates that the two galaxies are interacting and NGC 2673 has two tidal plumes, while NGC 2672 is only weakly disturbed.
Supernova
One supernova has been observed in NGC 2672: SN1938B (type unknown, mag. 15.5) was discovered by Arno Wachmann in 1938.
See also
List of NGC objects (2001–3000)
References
External links
2672
024790
04619
+03-23-010
Cancer (constellation)
17840314
Discoveries by William Herschel
Elliptical galaxies
167
Interacting galaxies | NGC 2672 | [
"Astronomy"
] | 319 | [
"Cancer (constellation)",
"Constellations"
] |
78,641,754 | https://en.wikipedia.org/wiki/BX%20Trianguli | BX Trianguli is a binary system made up of two red dwarfs, in the constellation Triangulum. Both stars eclipse each other and have an orbital period of four hours and 40 minutes. They are located at around 170 light-years from Earth based upon parallax measurements.
Variability
This is an eclipsing binary variable, first identified by the Northern Sky Variability Survey survey in 2004 and given its variable-star designation BX Trianguli in 2010. Both stars in the system eclipse each other as seen from Earth, causing the brightness of the system to drop from a magnitude of 12.35 to 12.6/12.7 on the secondary/primary ecplise respectively.
The system has also been identified as a flare star. Six flares were recorded between 2014 and 2017, the strongest being identified in November 2014, four times stronger than a typical superflare. The large occurrence of flares on BX Trianguli is the highest among eclipsing binaries after Castor C (YY Geminorum) and might be related to rapid mass transfer between the components. These flares likely occur on BX Trianguli B.
BX Trianguli also has strong magnetic activity, manifested as starspots on the primary's surface and Hα emission.
Characteristics
This system is composed of two red dwarfs, which have an ultra-short period of just hours and a separation of 1.33 solar radii, or two and a half times the distance to the Moon. This orbit is one of the shortest known among main sequence stars. The primary star, named BX Trianguli A, has a mass equivalent to 58% the solar mass and a radius equivalent to 60% of the solar radius, while the secondary BX Trianguli B is smaller, at 28% and 27% of the solar mass and radius respectively. BX Trianguli has a semi-detached configuration, with the "A" component being distorted due to gravitational interactions with its partner.
There is a star that could be bound to this system, called USNO-B1 1233−0046425, at roughly 3500 astronomical units of distance.
Planetary system
A circumbinary planet was discovered after analysis of eclipse timing variations by a high school student and his teacher. After rulling out alternative expanations for the eclipse timing variations, the two discoverers found that they are caused by a seven-Jupiter-mass planet at a separation of , with an orbital eccentricity of 0.4. The findings were published in 2024 at the American Association of Variable Star Observers's 113th Annual Meeting.
References
Triangulum
Planetary systems with one confirmed planet
M-type main-sequence stars
Binary stars
Objects with variable star designations
Flare stars
2MASS objects
Eclipsing binaries | BX Trianguli | [
"Astronomy"
] | 573 | [
"Triangulum",
"Constellations"
] |
78,641,902 | https://en.wikipedia.org/wiki/Lacra%20Pavel | Lăcrămioara (Lăcră) Pavel (born 1965) is a Romanian and Canadian game theorist and electrical engineer whose research applies game theory to network controllability for communications networks and transport networks. She is a professor of electrical and computer engineering at the University of Toronto.
Education and career
Pavel graduated from the Gheorghe Asachi Technical University of Iași in Romania in 1989. She received a Ph.D. in electrical engineering in 1996, from Queen's University at Kingston in Ontario, Canada.
She was a postdoctoral researcher for National Research Council Canada and then worked in industry before returning to academia in 2002, as a faculty member at the University of Toronto. She was promoted to full professor in 2013.
Book
Pavel is the author of the book Game Theory for Control of Optical Networks (Birkhäuser, 2012).
Recognition
Pavel was named to the 2025 class of IEEE Fellows "for contributions to game theory, control, and optimization for network systems".
References
External links
Home page
1965 births
Living people
Romanian electrical engineers
Romanian women engineers
Canadian electrical engineers
21st-century Canadian women engineers
Women electrical engineers
Game theorists
Gheorghe Asachi Technical University of Iași alumni
Queen's University at Kingston alumni
Academic staff of the University of Toronto
Fellows of the IEEE | Lacra Pavel | [
"Mathematics"
] | 257 | [
"Game theorists",
"Game theory"
] |
78,642,091 | https://en.wikipedia.org/wiki/Philip%20Warren | Philip Warren (born ) is an English ship model maker best known for building a matchstick Maritime Fleet. His constructions include over 500 vessels and 1,000 aircraft, as well as models of all Royal Navy ships since 1945.
Life and work
Philip Warren was born in Dorset, England, and was a director of a stationery wholesale company before his retirement. He started building models of naval boats at the age of 17 due to a fascination with ships. Like many children of his era, his interest in warships came about due to going through childhood during World War 2.
When he first began model making, he used balsa wood to make models. He switched to matchsticks because he found that material more suitable for static waterline warship models, and because matches were common. His models are hand-built and are made in 1/300th of the scale, using only a few building materials, including matchboxes, matchsticks, a razor blade, and glue. Completing his models requires him looking at photographs, drawings, and plans of real ships. His largest model is 1m (3ft) long.
When Warren began matchstick model making, matchboxes were easy to get a hold of, but in recent years, he has relied on donations to keep up with his work. He has continued model making into his 90s.
Models
Philip Warren's earliest model was the Royal Navy's HMS Scorpion, which was less detailed compared to later models. Following its completion, he built a different destroyer, a battleship, a cruiser, and later an aircraft carrier. As the years passed, his attention to detail and accuracy improved, making models with many moving parts, including missile launchers, radars, gun turrets, swing wings, and helicopter rotors. His collection of models includes 500 vessels and 1000 aircraft from the very last World War 2 battleships to nuclear-powered submarines and modern aircraft carriers.
In his over 70 years of model making, he built one or more of each class of Royal Navy ships from 1945 to the present day, including 7 Leander class frigates. In addition, he has also built Commonwealth ships. Also, Warren has constructed 60 US ships so far, including four giant supercarriers, two battleships, and various cruisers, demonstrating the evolution of vessels that contained guns to those with missiles. Additionally, he built around 50 ships from various Navies of other nations.
His aircraft models span from older aircraft, such as the Swordfish, to modern supersonic jets. Warren's model of the HMS Queen Elizabeth was completed before the original.
It can take Warren over a year to finish a model. He very rarely gets rid of models and has never made money from his hobby, despite being told by numerous museum curators that his models have considerable value. His models have not been built in historical sequence but preserved so well that it's difficult to tell which models are older. Warren’s ships take him approximately 1,500 matches to build. Adam Aspinall from The Mirror states, “Each vessel is correct to the tiniest detail.” In 1989, Philip gave the United Kingdom's Prince Andrew a model of the frigate Campbeltown. Trend Hunter named Warren the “Hobby King of Hobbydom” due to having built models of all of Britain's warships since the end of the Second World War.
Exhibits and Recognition
Various museums and charities have displayed Philip Warren's work, including the Fleet Air Arm Museum and Nothe Fort. The Duke of Gloucester honored him with a glass trophy for his service to the Northe Fort community for his yearly display of his matchstick fleet.
Personal life
Philip Warren was married to his wife Anita for 47 years until her death.
References
Year of birth missing (living people)
Living people
Model makers
Model
Scale modeling
People from Dorset | Philip Warren | [
"Physics"
] | 768 | [
"Model makers",
"Scale modeling"
] |
78,642,145 | https://en.wikipedia.org/wiki/Jumart | A jumart or jumar is a cryptozoological or folkloric hybrid between cattle (Bos taurus) and a species of equine (horse or donkey). Jumarts were once widely believed by Europeans to actually exist, and many people claimed to own or have encountered the animals. While they were discussed extensively in early scientific writings, such hybridization is now known to be biologically impossible, and many "jumarts" examined by later researchers were found to be hinnies (a horse/donkey hybrid) instead. The term is of French origin and most historical writings about supposed jumarts were in the French language.
References
Hybrid animals
French folklore | Jumart | [
"Biology"
] | 140 | [
"Intergeneric hybrids",
"Hybrid animals",
"Animals",
"Hybrid organisms"
] |
78,642,276 | https://en.wikipedia.org/wiki/Louisiana%20artificial%20reefs | The Louisiana Artificial Reef Program (ARP) was established in 1986 to create habitats for providing food, and shelter for marine life that includes coastal fish, using human-made structures. The program includes several types of artificial reefs that supports ecosystem development, recreational fishing and diving, and critical research. A secondary benefit for those close to shore is coastal protection by reducing the impact of storms, flooding, preventing loss of life, property damage, and coastal erosion.
In 1999, the Louisiana Artificial Reef Program created the world's largest artificial reef by area, referred to as Grand Isle #9, from the Freeport Sulfur Mine off Grand Isle.
As of 2021 oil companies have taken advantage of the Rigs-to-Reefs program with over 600 platforms converted and over 350 are in Louisiana.
History
In 1984 Congress passed the Louisiana Fishing Enhancement Act (LA R.S. 56:639.6 or Public Law 98-623, Title II). The law also created the National Artificial Reef Plan that allowed the establishment of a state reef-permitting system.
The Louisiana Artificial Reef Development Council (Artificial Reef Council) was also created under the Louisiana Artificial Reef Program. The members are the Secretary of the Louisiana Department of Wildlife and Fisheries, Dean of LSU College of the Coast and Environment, and the executive director of the Louisiana Sea Grant.
In 1990 the Coastal Wetlands Planning, Protection and Restoration Act (CWPPRA) was signed into law by then President George H. W. Bush to fund construction of coastal wetlands restoration projects. Since 1990 there has been 210 projects authorized.
The Rigs-to-Reefs program
In response to concerns of habitat loss when a rig ceases production the state created the Rigs-to-reefs program based on criteria from the national Rigs-to-reefs program. Companies can donate decommissioned platforms to the LDWF. Companies also donate half the money saved to the Louisiana Artificial Reef Trust Fund that was created along with the ARP. For platforms farther offshore this can be a tremendous savings as opposed to tearing the rig down and bringing it to shore. The Bureau of Safety and Environmental Enforcement (BSEE) oversees permitting. After a state accepts a donated rig the U.S. Army Corps of Engineers issues a permit, the state accepts liability and maintenance. In 2017 there were 350 platforms converted to reefs.
The process of Rigs-to-Reefs is complex and lengthy. After a company expresses interest to include a platform in the program, permits are required. The LDWF is the lead state agency, starts the permit process, and notifies all the other regulatory agencies. A process of planning, site selection, material selection, permitting, and monitoring of inshore, and nearshore artificial reef development. Both nearshore (normally considered 3 nautical miles) and inshore sites require additional permitting per the National Fishing Enhancement Act and Louisiana Fishing Enhancement Act. Nearshore and inshore sites see far more traffic than offshore.
The depth of or less means the oil platform jackets (legs) might have to be excluded. Leaving the jackets upright, but shortened to comply with minimum jacket to surface requirements, is usually the preferred option. Jackets already in place will have already become an unintended artificial reef. The reef design and development standards depends on certain factors being examined for each site. These include, among other things, environmental and biological factors as well as social and economic considerations. A United States Coast Guard buoy permit is required as the size of a buoy is dependent on the depth and location of water. All five Gulf of Mexico coastal states, Alabama, Florida, Louisiana, Mississippi, and Texas, have artificial reef programs, that includes decommissioned platforms. All five states have an artificial reef coordinator. In Louisiana the coordinator reviews an operator's reefing plan and secures a permit from the Corps of Engineers.
In water that extends from the states boundary to the continental shelf break of the continental margin, or seaward, whichever is farthest from the state boundary, the federal government has authority. Any potential rigs-to-reefs in areas under federal authority are also subject to US Corps of Engineers oversight and permitting as well as the Bureau of Safety and Environmental Enforcement (BSEE) and issuing of a permit. At the state level, the Coastal Management Division of the Louisiana Department of Natural Resources will examine the permits and plans to ensure compliance with state and federal guidelines. Once a structure is accepted into the State reef program, and the reefing operation is complete, the state assumes title and all responsibility for the structure. This includes an exemption from 30 CFR §250.1725(a).
The Coastal Protection and Restoration Authority (CPRA) is the lead agency concerning the criteria of coastal protection and funding. This includes the authority (oversight) for developing, implementing, and enforcing master and annual plans that are submitted to the Louisiana Legislature. The 2023 Coastal Master Plan, the fourth since inception and revised every six years, lays the foundation for current and future goals concerning the Louisiana coast protection, conservation, enhancement, and restoration. The authority of CPRA is vested by the Louisiana House and Senate through legislation (Louisiana Revised Statutes) R.S. 49:214.1, R.S. 49:214.5.3, and R.S. 49:214.5.3(E)
Opposition
Opponents to artificial reefs vary in their reasoning. Some materials have shown to not be suitable for artificial reefs because they are not "risk-free". Tires can become dislodged by storms, especially during extreme weather like hurricanes, and can potentially damaging natural coral reefs. Material erosion can result in toxic chemicals leaching into the water. Marine life can become entangled in the loose debris. In 1972 Firestone donated approximately 2,000,000 tires used at the "Osborne Reef" around a mile off the coast of Florida. Jack Sobel, Director of Strategic Conservation Science and Policy for The Ocean Conservancy and author stated, "We've literally dumped millions of tires in our oceans," and "I believe that people who were behind the artificial tire reef promotions actually were well-intentioned and thought they were doing the right thing. In hindsight, we now realize that we made a mistake." While some material or items have shown to be successful like the USS Spiegel Grove, sunk around from Key Largo, there are many things that are unknown like concerns that the reefs will attract the wrong species. The long term effect (100 to 200 years) is unknown, and over-fishing, because the sites are well advertised to attract fishermen.
List of artificial reefs
Converted oil platforms
As of 2021 oil companies have taken advantage of the Rigs-to-Reefs program with over 600 platforms converted and more than 350 in Louisiana.
The Lena platform, one of ExxonMobil's decommissioned platforms, located about 50 miles southeast of Grand Isle, was , and is the tallest structure to be converted to an artificial reef. The platform is in the Mississippi Canyon Area, Block 280, in 1,000 feet of water. It weighed and when upright was 50 feet taller than the Empire State Building. The platform was also the world's first First Cable-Stabilized Platform. Decommissioning began in 2017
Grand Isle #9: In 1999, the Louisiana Artificial Reef Program created the world's largest artificial reef by area. Created from the Freeport Sulfur Mine off Grand Isle, Louisiana the reef is made up of more than 68 structures with over 1.5 miles of bridgework. The reef is in 42–50 feet of water with of clearance.
Nearshore reefs
Louisiana Artificial Reef Program
Nearshore Reefs
Raising Cane’s Hotel Sid reef, located in the South Marsh Island Block 233 is a shallow artificial reef: A partnership between the Coastal Conservation Association (CCA) of Louisiana and Todd Graves founder of Raising Cane, who donated $500,000 to create an artificial reef named Raising Cane’s Hotel Sid reef. The reef is a combined partnership between the CCA’s REEF Louisiana Program, Danos Ventures (Amelia, Louisiana) and Climate technology company Natrx (Raleigh, North Carolina) the Louisiana Department of Wildlife and Fisheries (LDWF), Chevron, CCA’s Building Conservation Trust and Shell. The site is located where the platform Hotel Sid once stood. The platform removal destroyed an unintentional reef and the new reef is intended to mitigate that loss. The reef material, called Cajun Coral, are 3D printed concrete modules that allows project-specific ExoForms to be created.
References
External links
Louisiana Inshore and Nearshore Artificial Reef Plan
Atlantic States Marine Fisheries Commission "Special Report No. 38
Artificial reefs
Oil platforms
Coastal construction
Marine architecture
Reefs
Artificial landforms
United States Department of the Interior | Louisiana artificial reefs | [
"Chemistry",
"Engineering"
] | 1,772 | [
"Oil platforms",
"Structural engineering",
"Marine architecture",
"Petroleum technology",
"Construction",
"Coastal construction",
"Natural gas technology",
"Architecture"
] |
78,643,306 | https://en.wikipedia.org/wiki/HD%2077191 | HD 77191 is a spectroscopic binary composed of a Sun-like variable star and a probable red dwarf, located in the zodiac constellation of Cancer. It has the variable-star designation HL Cancri (abbreviated to HL Cnc). With an apparent magnitude of 8.88, it is too faint to be seen by the naked eye but observable using binoculars as a yellow-hued dot of light. 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 7.10 km/s.
The star is part of the Castor stream, a moving group of young stars that includes some of the brightest stars in the night sky, such as Castor, Fomalhaut, and Vega.
Stellar properties
The primary star is a G-type main-sequence star with the spectral type G0V, almost identical to the Sun in mass, effective temperature, and metallicity, but approximately 7% smaller in radius. Its spectrum shows clear signs of high stellar activity and a strong lithium doublet spectral line at wavelength 6707.8 Å, indicative of its youth, with an estimated age of . Accordingly, the star displays large starspots, which are responsible for slight variations in its brightness, first discovered in 2000 with a mean amplitude of about 0.025 mag and a period of (which is also the star's rotation period). Hence, the star is classified as a BY Draconis variable.
Data collected by Hipparcos suggested that the star was single, but radial velocity observations via the Coravel spectrograph at the University of Cambridge yielded a 44-day period orbit for a binary companion. By matching the primary's rotational velocities measured through Doppler broadening and its photometric period, the mass of the unseen secondary star is placed at roughly 0.38 , making it likely a red dwarf.
References
G-type main-sequence stars
M-type main-sequence stars
Binary stars
Spectroscopic binaries
Cancer (constellation)
Cancri, HL
077191
BD+11 01961
J09012277+1043585
044303 | HD 77191 | [
"Astronomy"
] | 467 | [
"Cancer (constellation)",
"Constellations"
] |
78,643,434 | https://en.wikipedia.org/wiki/Placemat%20%28graphic%20design%29 | A placemat in the context of graphic design is a visual, one-page summary of the key points of a topic or subject matter
usually layouted in landscape format.
It gets its name from the physical object of a household placemat whose size and aspect ratio it resembles.
References
Graphic design | Placemat (graphic design) | [
"Engineering"
] | 60 | [
"Design stubs",
"Design"
] |
78,643,718 | https://en.wikipedia.org/wiki/C/1911%20S2%20%28Qu%C3%A9nisset%29 | Comet Quénisset, also known by its modern formal designation C/1911 S2, is a non-periodic comet that has a 4,000-year retrograde orbit around the Sun. It is the second of two comets discovered by French astronomer, Ferdinand Quénisset.
Potential meteor shower
Orbital calculations by J. B. Dale revealed that although there would be no close encounter between the comet and the Earth, the former's descending node resulted in a minimum orbit intersection distance of about by 16 December 1911. This has led to other scientists predicting a meteor shower originating from this comet that will be coming from the constellation Vulpecula on April 27 of each year, though none has been observed so far.
References
External links
Non-periodic comets
Near-Earth comets | C/1911 S2 (Quénisset) | [
"Astronomy"
] | 156 | [
"Astronomy stubs",
"Comet stubs"
] |
78,644,233 | https://en.wikipedia.org/wiki/Perfect%20Timing%20Holding | Perfect Timing Holding (PTH) is a multinational group of companies headquartered in Turkey. It operates in Europe, Asia, America, and Africa.
PTH was established in 2000, through the merger of two family businesses: the Huseby company, founded in 1880 in America, and Yavuz, founded in 1925 in Turkey. PTH operates in several sectors, including real estate, higher education, information and communication technology, financial technology, healthcare, tourism, sports management and many more.
History
In 1880, Henry Huseby, a Northern Europe immigrant to the United States founded the Huseby Family company, based in Chicago and trading in antiques. After his death, his children diversified the business into media and tourism, expanding it within America and into Europe.
In 1925, Hüseyin Yavuz founded the Yavuz family business, a Turkish construction company operating in the Erzurum region of Turkey. His son, Mehmet Yavuz, expanded the company to Germany. In 1996, the eldest son, Şakir Yavuz took over the family business, diversifying into textiles, arts collection, consulting, sports management and media.
In 2000, the two companies merged, forming Perfect Timing Holding (PTH). With its headquarters in Türkiye, PTH operates in 22 countries across Africa, Asia, Europe, and America. Its subsidiaries include Atafom University International and the ConiaSoft software company.
References
Technological comparisons
Companies established in 2000
Turkish companies established in 1925
American companies established in 1880 | Perfect Timing Holding | [
"Technology"
] | 310 | [
"nan"
] |
78,645,068 | https://en.wikipedia.org/wiki/Extreme%20set | In mathematics, most commonly in convex geometry, an extreme set or face of a set in a vector space is a subset with the property that if for any two points some in-between point lies in , then we must have had .
An extreme point of is a point for which is a face.
An exposed face of is the subset of points of where a linear functional achieves its minimum on . Thus, if is a linear functional on and , then is an exposed face of .
An exposed point of is a point such that is an exposed face. That is, for all .
An exposed face is a face, but the converse is not true (see the figure). An exposed face of is convex if is convex.
If is a face of , then is a face of if and only if is a face of .
Competing definitions
Some authors do not include and/or among the (exposed) faces. Some authors require and/or to be convex (else the boundary of a disc is a face of the disc, as well as any subset of the boundary) or closed. Some authors require the functional to be continuous in a given vector topology.
See also
Face (geometry)
References
Bibliography
External links
VECTOR SPACES AND CONTINUOUS LINEAR FUNCTIONALS, Chapter III of FUNCTIONAL ANALYSIS, Lawrence Baggett, University of Colorado Boulder.
Analysis, Peter Philip, Ludwig-Maximilians-universität München, 2024
Convex geometry
Convex hulls
Functional analysis
Mathematical analysis | Extreme set | [
"Mathematics"
] | 295 | [
"Mathematical analysis",
"Functions and mappings",
"Functional analysis",
"Mathematical objects",
"Mathematical relations"
] |
78,645,761 | https://en.wikipedia.org/wiki/IRAS%2004125%2B2902 | IRAS 04125+2902 is a M-type star and a T Tauri variable located in the Taurus Molecular Cloud, from Earth. This young protostar has 70% of the Sun's mass, 1.45 times the Sun's radius and an effective temperature of . It has a very young age of three million years. It is surrounded by a transitional disk, inclined at 30° relative to Earth, and has one known exoplanet.
It is part of a binary system with 2MASS J04154269+2909558, the two being separated by a projected distance of 635 astronomical units, or 4 arcseconds in the sky. The companion was discovered in 2009, has a spectral type of M6.5, and does not show any infrared excess. Gaia astrometry is similar between 2MASS J04154269+2909558 and IRAS 04125+2902.
The dust disk around IRAS 04125+2902 is truncated, which could be caused by disk evolution or by an eccentric companion. It is unlikely that the wide companion is responsible for the disk truncation, as it's projected distance is much larger than the dust disk's outer limit, but given that the orbital eccentricity of the companion is unknown, this remains plausible.
Planetary system
IRAS 04125+2902 hosts one confirmed exoplanet, IRAS 04125+2902 b, which has an orbital period of nine days around its star, orbiting it closely. It was discovered in 2024 using the transit method and is the youngest transiting exoplanet so far discovered. It is notable as a precursor of super-Earths or sub-Neptunes, commonly found planets. The planet is currently similar to Jupiter in size and it's mass is constrained to be less than . Over time, it will become a sub-Saturn or sub-Neptune with 60% of its current size or less.
The outer disk is misaligned with the planet and the outer companion, which could be caused by infalling material from the Taurus molecular cloud, but this remains unclear. This misaligment also made it possible to detect IRAS 04125+2902 b via the transit method.
See also
V830 Tauri – Similar to IRAS 04125+2902 and has an unconfirmed planet
References
Binary stars
M-type main-sequence stars
IRAS catalogue objects
Circumstellar disks
Planetary systems with one confirmed planet | IRAS 04125+2902 | [
"Astronomy"
] | 525 | [
"Taurus (constellation)",
"Constellations"
] |
75,643,622 | https://en.wikipedia.org/wiki/Cheng%20Soo-chen | Cheng Soo-chen (; born 1955) is a Taiwanese biochemist.
Education and career
After graduating from National Taiwan University, Chen attended Duke University from 1978 to 1983, where she earned a doctorate in biochemistry. She conducted postdoctoral research at the National Institutes of Health from 1983 to 1984, and was a research fellow and senior research fellow at Caltech between 1984 and 1988.
Cheng began her affiliation with Academia Sinica in 1977, as a research assistant for the Institute of Biological Chemistry. After returning to Taiwan upon the completion of her Ph.D., Cheng joined Academia Sinica's Institute of Molecular Biology, starting out as an associate research fellow. She was promoted to research fellow in 1994, and became a distinguished research fellow in 2003. Cheng was deputy director of the Institute of Molecular Biology between 2006 and 2008, and served as institute director from 2013 to 2016. She held a joint appointment as distinguished research fellow for the Academia Sinica's Genomics Research Center from 2004 to 2016.
Cheng was adjunct faculty at National Yang-Ming University from 1989 to 2013, and began teaching at National Taiwan University as a full professor in 2013.
Honors and awards
Cheng shared the 2010 TWAS Prize in Biology with Satyajit Mayor. Chang was elected a member of Academia Sinica in 2012, and a fellow of The World Academy of Sciences in 2013.
References
Living people
1955 births
Taiwanese biochemists
Academic staff of the National Taiwan University
National Taiwan University alumni
Taiwanese expatriates in the United States
TWAS fellows
Members of Academia Sinica
Duke University alumni
20th-century Taiwanese scientists
Women biochemists
21st-century Taiwanese scientists
20th-century biochemists
21st-century biochemists | Cheng Soo-chen | [
"Chemistry"
] | 337 | [
"Biochemists",
"Women biochemists"
] |
75,643,932 | https://en.wikipedia.org/wiki/Victor%20Aladjev | Victor Zakharovich Aladjev (; born June 14, 1942) is an Estonian mathematician and cybernetician, creator of the scientific school on the theory of homogeneous structures.
Early life and education
Victor Aladjev was born in 1942 in Grodno to parents Zakhar Ivanovich Aladjev and Maria Adolfovna Novogrotska. His father participated in the underground resistance organization during World War II while in German-occupied Grodno.
Aladjev attended University of Grodno in 1959, later transferring to the University of Tartu, Estonia in 1962, where he earned his degree in mathematics in 1966. Subsequently, he entered the graduate school of the Estonian Academy of Sciences in 1969, achieving a doctorate in mathematics (DSc) in 1972, specializing in Theoretical Cybernetics and Technical Cybernetics. His doctoral work focused on the mathematical theory of homogeneous structures, resulting in the award of a DSc under the guidance of Professor Richard E. Bellman.
Scientific career
In 1970, Aladjev became the President of the Tallinn Research Group (TRG), contributing to the mathematical theory of homogeneous structures, particularly Cellular Automata (CA). Between 1972 and 1990, Aladjev held various senior positions in design, technological, and research organizations in Tallinn.
His involvement in international mathematical publications includes serving as a referent and editorial board member for Zentralblatt für Mathematik since 1972 and being a member of International Association of Mathematical Modeling (IAMM) since 1980. In 1993, he was elected to the International Federation for Information Processing (IFIP) working group on the mathematical theory of homogeneous structures and its applications.
In 1994, Aladjev was honored with election as an academician of the Russian Academy of Cosmonautics and the International Academy of Noosphere (IAN). The following year, in 1995, he achieved full membership in the Russian Academy of Natural Sciences (RANS). By 1998, he rose to the position of First Vice-president of the IAN.
Research
Aladjev is the author of more than 500 scientific works, including 90 monographs, textbooks, and articles. Particularly noteworthy is his 1972 monograph on the theory of homogeneous structures, acknowledged as one of the finest monographic publications by the Estonian Academy of Sciences. It received recognition in the Encyclopedia of Physical Science and Technology. This monograph not only unveiled numerous original findings, but also introduced fundamental terminology on cellular automata, now widely accepted in the field.
Aladjev is a member of the editorial boards of a number of scientific journals. He created the Estonian School for the mathematical theory of homogeneous structures, whose fundamental results received international recognition and have made certain contributions in the basis of a new division of the modern mathematical cybernetics. He also created the UserLib6789 library of new software (more than 850 tools) for which he was won the Smart Award network award, and a large unified MathToolBox package (more than 1420 tools) for Maple and Mathematica systems.
As part of the Visiting Professor program, Aladjev collaborated with various universities in the computer science, delivering lectures on Maple and Mathematica systems. In recognition of his contributions, he was awarded the Gold Medal European Quality in May 2015 by the European Scientific & Industrial Consortium (ESIC). Aladjev's work on cellular automata gained acknowledgment, with one publication listed in the top 100 e-books in discrete mathematics by BookAuthority.
Personal life
Apart from his academic pursuits, Aladjev actively participated in the annual international sport events (Spartakiad) from 1976 to 1990, achieving success and winning several medals in athletics and volleyball.
Selected publications
Computability in homogeneous structures. V Aladyev, Izv. Akad. Nauk. Estonian SSR, Fiz.-Mat, 1972
Survey of research in the theory of homogeneous structures and their applications. V Aladyev, Mathematical Biosciences, 1974.
Mathematical Theory of Homogeneous Structures and Their Applications. Victor Alajev. Valgus Press, Tallinn, 1980.
Computer laboratory for engineering researches. VZ Aladjev, ML Shishakov, TA Trokhova, Intern. Conf. ACA-2000.–Saint-Petersburg, Russia, 2000.
A workstation for solution of systems of differential equations. VZ Aladjev, ML Shishakov, TA Trokhova - 3rd Int., 2000.
Educational computer laboratory of the engineer. VZ Aladjev, ML Shishakov, TA Trokhova - Proc. 8th Byelorussia Mathemat. Conf, 2000.
Maple 6: Solution of the Mathematical, Statistical and Engineering–Physical Problems. V Aladjev, M Bogdevicius, Laboratory of Basic Knowledge's, Moscow, 2001.
New software for mathematical package Maple of releases 6, 7 and 8. V Aladjev, M Bogdevičius, O Prentkovskis, Technika, 2002.
Classical cellular automata. Homogeneous structures. Aladjev, V., Fultus Books, 2010. ISBN 9781596822221
Classical cellular automata: Mathematical theory and applications. Aladjev, V., Scholar's Press, 2014. ISBN 9783639713459
Toolbox for the Mathematica programmers. V. Aladjev, V. Vaganov., CreateSpace Independent Publishing Platform, 2016. ISBN 9781532748837
Software Etudes in the Mathematica: Tallinn Research Group. Aladjev, Victor; Shishakov, Michael, CreateSpace Independent Publishing Platform, 2017.
Selected problems in the theory of classical cellular automata. Aladjev, Victor Zachar; Shishakov, Michael Leonid; Vaganov, Vjacheslav Alexei, Independently published, 2018.
Functional and procedural programming in Mathematica. Aladjev, V.; Shishakov, M.; Vaganov, V., TRG press, 2020.
Cellular automata, mainframes, Maple, Mathematica and computer science in Tallinn Research Group. Aladjev, V., Kindle Press, 2022. ISBN 9798447660208
References
1942 births
Applied mathematicians
Living people
Estonian mathematicians | Victor Aladjev | [
"Mathematics"
] | 1,311 | [
"Applied mathematics",
"Applied mathematicians"
] |
75,644,239 | https://en.wikipedia.org/wiki/Dextran%20sulphate%20sodium | Dextran sulphate sodium (DSS), or dextran sodium sulphate (or any of the former with "sulfate") is a synthetic sulphated polysaccharide with anticoagulant activity used in immunological research to induce colitis. Dextran polymer molecules with a molecular weight of 36–50 kDa are frequently used to this end.
DSS-induced colitis
DSS-induced colitis is the most widely used mouse model of colitis, such as is seen in inflammatory bowel disease (IBD). Acute colitis can be achieved within 7-10 days, while chronic colitis can be induced by 3-5 cycles of the former with 1-2 weeks in between each cycle.
Mechanism
DSS is thought to induce colitis by causing injury to the colonic epithelium. The sulphate groups make the dextran molecules highly negatively charged and induce erosions in the epithelium, eventually compromising its integrity and increasing its permeability, while DSS's anticoagulant action promotes intestinal bleeding.
References
Anticoagulants
Polysaccharides | Dextran sulphate sodium | [
"Chemistry"
] | 240 | [
"Carbohydrates",
"Polysaccharides"
] |
75,645,078 | https://en.wikipedia.org/wiki/Loteprednol/tobramycin | Loteprednol/tobramycin, sold under the brand name Zylet, is a fixed-dose combination medication used for the treatment of inflammation of the eye. It is a combination of loteprednol, as the etabonate, a corticosteroid; and tobramycin, an aminoglycoside antibiotic. It is used as drops in the eye.
Loteprednol/tobramycin was approved for medical use in the United States in December 2004.
References
Further reading
Aminoglycoside antibiotics
Combination drugs
Corticosteroids
Ophthalmology drugs | Loteprednol/tobramycin | [
"Chemistry"
] | 129 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
75,645,118 | https://en.wikipedia.org/wiki/IBM%20Heron | IBM Heron is a 156-qubit tunable-coupler quantum processor created by IBM, originally unveiled during the IBM Quantum Summit 2023, which occurred on December 4, 2023, and is the highest performance quantum processor IBM has ever built.
It is currently in use on the IBM Quantum System Two, unveiled during the same event.
IBM claims that this processor eliminates cross-talk errors that emerged in their previous quantum processors, and that this processor is being made available for users via the cloud.
The first version is reportedly 5 times faster than their previous best record set by the IBM Eagle.
IBM Heron r2
During the IBM Quantum Developer Conference, a second revision (called r2) was released, which increased the qubit count from 133 to 156, and introduced a two-level system mitigation to reduce the impact of an important source of noise.
References
Quantum computing
IBM microprocessors | IBM Heron | [
"Technology"
] | 185 | [
"Computing stubs",
"Computer hardware stubs"
] |
75,646,993 | https://en.wikipedia.org/wiki/Oxalate%20chloride | An oxalate chloride or oxalato chloride is a mixed anion compound contains both oxalate and chloride anions.
Related compounds include oxalate fluorides and oxalate bromides.
Production
Oxalate chlorides may be produced by treating an oxalate salt with concentrated hydrochloric acid, or with a metal oxide dissolved in oxalic acid and hydrochloric acid solutions that are evaporated.
List
References
Oxalates
Chlorides
Mixed anion compounds | Oxalate chloride | [
"Physics",
"Chemistry"
] | 103 | [
"Matter",
"Chlorides",
"Inorganic compounds",
"Mixed anion compounds",
"Salts",
"Ions"
] |
75,647,518 | https://en.wikipedia.org/wiki/Counterexample-guided%20abstraction%20refinement | Counterexample-guided abstraction refinement (CEGAR) is a technique for symbolic model checking. It is also applied in modal logic tableau calculi algorithms to optimise their efficiency.
In computer-aided verification and analysis of programs, models of computation often consist of states. Models for even small programs, however, may have an enormous number of states. This is identified as the state explosion problem. CEGAR addresses this problem with two stages — abstraction, which simplifies a model by grouping states, and refinement, which increases the precision of the abstraction to better approximate the original model.
If a desired property for a program is not satisfied in the abstract model, a counterexample is generated. The CEGAR process then checks whether the counterexample is spurious, i.e., if the counterexample also applies to the under-abstraction but not the actual program. If this is the case, it concludes that the counterexample is attributed to inadequate precision of the abstraction. Otherwise, the process finds a bug in the program. Refinement is performed when a counterexample is found to be spurious. The iterative procedure terminates either if a bug is found or when the abstraction has been refined to the extent that it is equivalent to the original model.
Program verification
Abstraction
To reason about the correctness of a program, particularly those involving the concept of time for concurrency, state transition models are used. In particular, finite-state models can be used along with temporal logic in automatic verification. The concept of abstraction is thus founded upon a mapping between two Kripke structures. Specifically, programs can be described with control flow automata (CFA).
Define a Kripke structure as , where
is a finite set of states,
is an initial state in ,
is a total transition relation, and
is a function that labels each state with a set of propositional names that hold therein.
An abstraction of is defined by where is an abstraction mapping that maps every state in to a state in .
To preserve the critical properties of the model, the abstraction mapping maps the initial state in the original model to its counterpart in the abstract model. The abstraction mapping also guarantees that the transition relations between two states are preserved.
Model Checking
In each iteration, model checking is performed for the abstract model. Bounded model checking, for instance, generates a propositional formula that is then checked for Boolean satisfiability by a SAT solver.
Refinement
When counterexamples are found, they are examined to determine if they are spurious examples, i.e., they are unauthentic ones that emerge from the under-abstraction of the model. A non-spurious counterexample reflects the incorrectness of the program, which may be sufficient to terminate the program verification process and conclude that the program is incorrect. The main objective of the refinement process handle spurious counterexamples. It eliminates them by increasing the granularity of the abstraction.
The refinement process ensures that the dead-end states and the bad states do not belong to the same abstract state. A dead-end state is a reachable one with no outgoing transition whereas a bad-state is one with transitions causing the counterexample.
Tableau calculi
Since modal logic is often interpreted with Kripke semantics, where a Kripke frame resembles the structure of state transition systems concerned in program verification, the CEGAR technique is also implemented for automated theorem proving.
References
Model checking
Logical calculi
Modal logic | Counterexample-guided abstraction refinement | [
"Mathematics"
] | 733 | [
"Mathematical logic",
"Logical calculi",
"Modal logic"
] |
75,647,565 | https://en.wikipedia.org/wiki/Modal%20clausal%20form | Modal clausal form, also known as separated normal form by modal levels (SNFml) and Mints normal form, is a normal form for modal logic formulae.
Such a normal form is commonly used for automated theorem proving using tableau calculi and resolution calculi techniques due to its benefits of better space bounds and improved decision procedures. In normal modal logic, any set of formulae can be transformed into an equisatisfiable set of formulae in this normal form.
In multimodal logic where a represents an agent corresponding to an accessibility relation function in Kripke semantics, a formula in this normal form is a conjunction of clauses labelled by the modal level (i.e., the number of nested modalities). Each modal level consists of three forms as follows.
Literal clause: a disjunction of propositional literals .
Positive a-clause: where and are propositional literals.
Negative a-clause: where and are propositional literals.
These three forms are also called cpl-clauses, box-clauses and dia-clauses respectively. Note that any clause in conjunctive normal form (CNF) is also a literal clause in this normal form.
References
Normal forms (logic)
Modal logic | Modal clausal form | [
"Mathematics"
] | 267 | [
"Mathematical logic",
"Modal logic"
] |
75,647,732 | https://en.wikipedia.org/wiki/C18H26N2O | {{DISPLAYTITLE:C18H26N2O}}
The molecular formula C18H26N2O (molar mass: 286.419 g/mol) may refer to:
AP-238
Bay R 1531 | C18H26N2O | [
"Chemistry"
] | 52 | [
"Isomerism",
"Set index articles on molecular formulas"
] |
75,648,310 | https://en.wikipedia.org/wiki/Joaquim%20Martins | Joaquim R. R. A. Martins is an aerospace engineer, academic, and author. He is the Pauline M. Sherman Collegiate Professor in the Department of Aerospace Engineering at the University of Michigan, where he directs the Multidisciplinary Design Optimization Laboratory (MDO Lab). He also has a courtesy appointment in the Department of Naval Architecture and Marine Engineering.
Martins is known for his research in methods for multidisciplinary design optimization (MDO) and its applications to the design of aircraft and other engineering systems. He is the author of the textbook Engineering Design Optimization.
Martins is a Fellow of the Royal Aeronautical Society and the American Institute of Aeronautics and Astronautics. He is the recipient of the Ballhaus Prize, the British Aerospace Award, and a Marie Skłodowska–Curie Fellowship. He has been a member of the AIAA Multidisciplinary Design Optimization Technical Committee. Additionally, he is a member of the International Organizing Committee for the Aircraft Structural Design Conference and AIAA Aerodynamic Design Optimization Discussion Group.
Early life and education
Martins was born in Porto, Portugal, and grew up in the Azores, in the city of Horta. He earned his Master of Engineering in Aeronautics from Imperial College, London in 1995. Before moving to London, he completed one year at the University of Oslo. For his final Master of Engineering project, he was a Visiting Researcher at the Israel Institute of Technology. He then obtained a Master of Science in Aeronautics and Astronautics at Stanford University in 1997, where he became a Research Assistant and completed his Ph.D. in 2002.
Career
Martins started his academic career at the University of Toronto Institute for Aerospace Studies, where he was an assistant professor from 2002 to 2008 and associate professor until 2009. Throughout his tenure at the University of Toronto, he held the Canada Research Chair in Multidisciplinary Design Optimization. He then took the role of associate professor in the Department of Aerospace Engineering at the University of Michigan, where he was promoted to Full Professor in 2015. He held a Visiting Professorship at the ISAE–SUPAERO Institut Supérieur de l’Aéronautique et de l’Espace in Toulouse from 2015 to 2016, where he was a Marie Skłodowska–Curie Fellow. Since 2021, he has been the Pauline M. Sherman Collegiate Professor in the Department of Aerospace Engineering at the University of Michigan, concurrently holding a courtesy appointment as a professor in the Department of Naval Architecture and Marine Engineering.
Martins was the Technical Co-chair for the 12th AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference in 2008. He was a co-organizer for the Fields Industrial Optimization Seminars and NSF Workshop titled "The Future of Multidisciplinary Design Optimization: Advancing the Design of Complex Systems". Moreover, he co-organized the UTIAS–MITACS International Workshop on Aviation and Climate Change in Toronto.
Research
Martins' studies have contributed to the understanding of the architectures and practical applications of MDO. He, with Andrew B. Lambe, introduced the extended design structure matrix to show data dependencies and process flows in MDO. They also described and classified MDO architectures based on problem formulation, discussing their benefits and drawbacks from both theoretical and practical perspectives.
Martins developed methodologies and software for aerodynamic shape optimization based on computational fluid dynamics (CFD) for aircraft design as well as other applications, including the shape optimization of cars, wind turbines, and hydrofoils. He addressed the absence of a standard benchmark problem in aerodynamic shape optimization by tackling problems based on the Common Research Model wing.
Martins is best known for pioneering high-fidelity MDO where CFD is coupled to structural finite-element analysis, propulsion thermal cycle analysis, and conjugate heat transfer. The key contribution of his work is the coupled-adjoint method, which computes derivatives of coupled systems efficiently to inform gradient-based optimization algorithms such as SNOPT. Applications have included the aerostructural optimization of airliner wings, wind turbine blades, and hydrofoils.
In collaboration with his students and NASA Glenn Research Center, Martins generalized the coupled-adjoint method and implemented it in OpenMDAO framework. Much of the theory behind OpenMDAO is explained in his book, Engineering Design Optimization.
Martins has also co-developed the Python optimization interface pyOptSparse, the surrogate modeling toolbox (SMT), and the high-fidelity multiphysics MDO framework MPhys.
Awards and honors
1995 – British Aerospace Award, Imperial College London
2002 – Best Paper Award, AIAA/ISSMO Symposium on Multidisciplinary Analysis and Optimization
2003 – Ballhaus Prize for Best Thesis, Stanford University
2006 – Best Paper Award, AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference
2012 – Best Paper Award, AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference
2014 – Best Paper Award, AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference
2015 – Marie Skłodowska–Curie Fellowship
2019 – Best Paper Award in Applied Aerodynamics, AIAA SciTech Forum
2019 – Fellow, Royal Aeronautical Society
2020 – Fellow, American Institute of Aeronautics and Astronautics
2023 – Best Paper in Multidisciplinary Design Optimization, AIAA Aviation and Aeronautics Forum and Exposition
Bibliography
Books
Selected articles
Martins, J. R. R. A., Sturdza, P., and Alonso, J. J. (2003). The complex-step derivative approximation. ACM Transactions on Mathematical Software (TOMS), 29(3), 245–262. doi: 10.1145/838250.838251
Martins, J. R. R. A., and Lambe, A. B. (2013). Multidisciplinary design optimization: a survey of architectures. AIAA journal, 51(9), 2049–2075. doi: 10.2514/1.J051895
Gray, J. S., Hwang, J. T., Martins, J. R. R. A., Moore, K. T., and Naylor, B. A. (2019). OpenMDAO: An open-source framework for multidisciplinary design, analysis, and optimization. Structural and Multidisciplinary Optimization, 59, 1075–1104. doi: 10.1007/s00158-019-02211-z
Brelje, B. J., & Martins, J. R. R. A. (2019). Electric, hybrid, and turboelectric fixed-wing aircraft: A review of concepts, models, and design approaches. Progress in Aerospace Sciences, 104, 1–19. doi: 10.1016/j.paerosci.2018.06.004
Martins, J. R. (2022). Aerodynamic design optimization: Challenges and perspectives. Computers & Fluids, 239, 105391. doi: 10.1016/j.compfluid.2022.105391
Adler, E. J., & Martins, J. R. (2023). Hydrogen-powered aircraft: fundamental concepts, key technologies, and environmental impacts. Progress in Aerospace Sciences, 141, 100922. doi: 10.1016/j.paerosci.2023.100922
References
External links
OpenMDAO
Joaquim R. R. A. Martins on Google Scholar
Joaquim Martins on ResearchGate
21st-century non-fiction writers
Aerospace engineers
Alumni of Imperial College London
Fellows of the American Institute of Aeronautics and Astronautics
Living people
Fellows of the Royal Aeronautical Society
Stanford University alumni
University of Michigan faculty
Year of birth missing (living people) | Joaquim Martins | [
"Engineering"
] | 1,598 | [
"Aerospace engineers",
"Aerospace engineering"
] |
75,649,648 | https://en.wikipedia.org/wiki/SMASH%20Handheld | SMASH Handheld in hebrew: פגיון (Pigyon), is a high-tech fire-control system developed by the Israel-based company SMARTSHOOTER. The device is an external add-on solution that can be installed to most existing firearms. The Israel Defense Force praised the technology and described the device as "groundbreaking" after its successful use in the 2023 Israel-Hamas War, claiming that "it quadruples the forces" chances of hitting their target, and thousands of it have already been used by the soldiers in the Gaza Strip. In 2011, Smart Shooter raised 20 million dollars in a seed venture funding.
Mechanisms and functionality
SMASH which is a contraction of the three first letters of "Smart" and two first letters of "Shooter".
When installed on an assault rifle, it uses an advanced artificial intelligence-powered machine vision to assist in aiming shots more precisely. The dual-core computer with ballistic processing can recognize, track, and engage aerial (drone/UAS) and ground targets with precision.
It is currently in use by Israel, The United Kingdom, the USA, India, and other countries.
The system consists of a digital camera, a display for the shooter, a trigger guard, and a firing computer capable of locking onto a moving target, analyzing its speed, and environmental conditions (distance, wind, humidity), and estimating when and how a bullet fired by the shooter will hit the target with a 95% probability. SMASH locks on the target and tracks its movement to synchronize the shot release. When the computer identifies such a hit probability, it sends a signal to the shooter, marking with a red dot or a red cross on the sight display to allow for accurate aiming. The trigger guard prevents firing when the computer estimates a low chance of hitting the target. The sight's camera also records the shooting, allowing for operational investigation when necessary.
SMASH can also be used in a remote-controlled fire control system.
See also
Aselsan SMASH
References
Weapons platforms
Israeli inventions
Optical devices
Military equipment introduced in the 2020s | SMASH Handheld | [
"Materials_science",
"Engineering"
] | 420 | [
"Glass engineering and science",
"Optical devices"
] |
75,649,937 | https://en.wikipedia.org/wiki/Comparison%20of%20retired%20orbital%20launch%20systems | This comparison of retired orbital launch systems lists the attributes of all retired individual rocket configurations designed to reach orbit. For a list of proposed rocket configurations or individual configurations currently being launched check out Comparison of Orbital Launch Systems.
Retired rockets
Retired Atlas rockets
Retired Delta rockets
Retired Thor rockets
Notes
References
Outer space lists
Technological comparisons | Comparison of retired orbital launch systems | [
"Astronomy",
"Technology"
] | 62 | [
"nan",
"Outer space",
"Outer space lists"
] |
75,650,409 | https://en.wikipedia.org/wiki/Liqun%20Zhang | Liqun Zhang is the president of South China University of Technology and Xi'an Jiaotong University.
Education
Zhang obtained his BS (1990), MS (1992) and PhD (1995) degrees from Beijing University of Chemical Technology. He was a visiting scholar at the University of Akron from 1990 to 2000. He held a postdoctoral position at Case Western Reserve University from 2000 to 2001.
Career
Zhang has been a professor at the College of Materials Science and Engineering (CMSE) at BUCT since 1995, and College Dean since 2016.
He accepted a position as president of SCUT in 2021. During his tenure, the university has established partnerships with BASF, with NTU Singapore, with Mahidol University.
Zhang is a member of the editorial board of the scientific journal Nano-Structures and Nano-Objects.
His most cited work concerns the application of a Halloysite clay nanotube to achieve a delayed release of antioxidants in a rubber compound, thus achieving an enhancement to anti-ageing properties.
Awards and recognition
2012 - Sparks–Thomas award from the ACS Rubber Division.
2012 - SCEJ Asia Research Award, The Society of Chemical Engineering, Japan
2014 - Morand Lambla Award from International Polymer Processing Society
2021 - Colwyn medal of the IOM3
2021 - Fellow of the Chinese Academy of Engineering
References
Polymer scientists and engineers
Members of the Chinese Academy of Engineering
1960s births
Living people
Year of birth missing (living people)
Beijing University of Chemical Technology alumni | Liqun Zhang | [
"Chemistry",
"Materials_science"
] | 300 | [
"Polymer scientists and engineers",
"Physical chemists",
"Polymer chemistry"
] |
75,650,483 | https://en.wikipedia.org/wiki/Bayesian%20persuasion | In economics and game theory, Bayesian persuasion involves a situation where one participant (the sender) wants to persuade the other (the receiver) of a certain course of action. There is an unknown state of the world, and the sender must commit to a decision of what information to disclose to the receiver. Upon seeing said information, the receiver will revise their belief about the state of the world using Bayes' Rule and select an action. Bayesian persuasion was introduced by Kamenica and Gentzkow, though its origins can be traced back to Aumann and Maschler (1995).
Bayesian persuasion is a special case of a principal–agent problem: the principal is the sender and the agent is the receiver. It can also be seen as a communication protocol, comparable to signaling games; the sender must decide what signal to reveal to the receiver to maximize their expected utility. It can also be seen as a form of cheap talk.
Example
Consider the following illustrative example. There is a medicine company (sender), and a medical regulator (receiver). The company produces a new medicine, and needs the approval of the regulator. There are two possible states of the world: the medicine can be either "good" or "bad". The company and the regulator do not know the true state. However, the company can run an experiment and report the results to the regulator. The question is what experiment the company should run in order to get the best outcome for themselves. The assumptions are:
Both company and regulator share a common prior probability that the medicine is good.
The company must commit to the experiment design and the reporting of the results (so there is no element of deception). The regulator observes the experiment design.
The company receives a payoff if and only if the medicine is approved.
The regulator receives a payoff if and only if it provides an accurate outcome (approving a good medicine or rejecting a bad one).
For example, suppose the prior probability that the medicine is good is 1/3 and that the company has a choice of three actions:
Conduct a thorough experiment that always detects whether the medicine is good or bad, and truthfully report the results to the regulator. In this case, the regulator will approve the medicine with probability 1/3, so the expected utility of the company is 1/3.
Don't conduct any experiment; always say "the medicine is good". In this case, the signal does not give any information to the regulator. As the regulator believes that the medicine is good with probability 1/3, the expectation-maximizing action is to always reject it. Therefore, the expected utility of the company is 0.
Conduct an experiment that, if the medicine is good, always reports "good", and if the medicine is bad, it reports "good" or "bad" with probability 1/2. Here, the regulator applies Bayes' rule: given a signal "good", the probability that the medicine is good is 1/2, so the regulator approves it. Given a signal "bad", the probability that the medicine is good is 0, so the regulator rejects it. All in all, the regulator approves the medicine in 2/3 of the cases, so the expected utility of the company is 2/3.
In this case, the third policy is optimal for the sender since this has the highest expected utility of the available options. Using the Bayes rule, the sender has persuaded the receiver to act in a favorable way to the sender.
Generalized model
The basic model has been generalized in a number of ways, including:
The receiver may have private information not shared with the sender.
The sender and receiver may have a different prior on the state of the world.
There may be multiple senders, where each sends a signal simultaneously and all receivers receive all signals before acting.
There may be multiple senders who send signals sequentially, and the receiver receives all signals before acting.
There may be multiple receivers, including cases where each receives their own signal, the same signal, or signals which are correlated in some way, and where each receiver may factor in the actions of other receivers.
A series of signals may be sent over time.
Practical application
The applicability of the model has been assessed in a number of real-world contexts:
Disclosure of capital reserves by banks to financial regulators.
Grading of students' work by teachers, where the receivers are potential future employers.
Provision of feedback by an employer to employees.
Revelation of plot points from a creator of fictional work to entertain its reader or viewer.
Computational approach
Algorithmic techniques have been developed to compute the optimal signalling scheme in practice. This can be found in polynomial time with respect to the number of actions and pseudo-polynomial time with respect to the number of states of the world. Algorithms with lower computational complexity are also possible under stronger assumptions.
The online case, where multiple signals are sent over time, can be solved efficiently as a regret minimization problem.
References
Applications of Bayesian inference
Mechanism design | Bayesian persuasion | [
"Mathematics"
] | 1,031 | [
"Game theory",
"Mechanism design"
] |
75,653,244 | https://en.wikipedia.org/wiki/Sophie%20Tarbouriech | Sophie Tarbouriech (born 1964) is a French control theorist whose research interests include linear and nonlinear control with limited information, anti-windup mechanisms, and the control of hybrid dynamical systems, with applications including aircraft landing control and surgical anesthesia. She is a director of research for the French National Centre for Scientific Research (CNRS), affiliated with the Laboratory for Analysis and Architecture of Systems in Toulouse, and the editor-in-chief of Journal Europeen des Systemes Automatises.
Early life and education
Tarbouriech was born in 1964 in Carcassonne. She was a student at Toulouse III - Paul Sabatier University, where she earned a Diplôme d'Etudes Approfondies (the equivalent of a master's degree) in 1988. She completed her doctorate there in 1991, directed by Christian Burgat. She earned a habilitation there in 1998.
Recognition
Tarbouriech was named an IEEE Fellow, in the 2024 class of fellows, "for contributions to nonlinear control systems with isolated nonlinear elements".
References
External links
Home page
1964 births
Living people
People from Carcassonne
French electrical engineers
Women electrical engineers
Control theorists
Paul Sabatier University alumni
Research directors of the French National Centre for Scientific Research
Fellows of the IEEE
20th-century French women engineers
21st-century French women engineers
20th-century French engineers
21st-century French engineers | Sophie Tarbouriech | [
"Engineering"
] | 286 | [
"Control engineering",
"Control theorists"
] |
75,653,738 | https://en.wikipedia.org/wiki/Hover%20%28behaviour%29 | Hovering is the ability exhibited by some winged animals to remain relatively stationary in midair. Usually this involves rapid downward thrusts of the wings to generate upward lift. Sometimes hovering is maintained by flapping or soaring into a headwind; this form of hovering is called "wind hovering", "windhovering", or "kiting".
True hoverers
Hummingbirds
Hummingbirds hover over flowers to obtain nectar, flapping their wings at up to 70 beats per second.
Bats
Like hummingbirds, fruit bats and nectar bats hover over flowers while feeding on fruits or nectar. Comparison between bats and hummingbirds has revealed that these animals exert similar amounts of energy relative to body weight during hovering: hummingbirds can twist their wings more easily and are more aerodynamic, but bats have bigger wings and larger strokes.
Kingfishers
Small Kingfishers such as Belted kingfisher may hover over water before diving in to catch fish.
Larger species such as Ringed kingfisher are too heavy to hover for more than a few seconds.
Moths
Sphinx moths
Some sphinx moths (family Sphingidae) are known as hummingbird moths for their ability to hover over flowers while nectaring. Moths are relatively heavy insects and sometimes hang on to the flower with their forelegs as they hover.
Clearwing moths
Some clearwing moths (family Sesiidae) also hover while nectaring
or even puddling.
Females may also hover to inspect ovipositing sites.
Hoverflies
Hoverflies are flies that often hover over the plants they visit. This hovering behaviour is unlike that of hummingbirds since they do not feed in midair. Hovering in general may be a means of finding a food source; in addition, male hovering is often a territorial display seeking females,
while female hovering serves to inspect ovipositing sites.
Bee flies
Bee flies are parasitoids that can dart about in the air with great agility. Males hover as a courtship display,
while females hover over ovipositing sites - usually the entrance of a host insect nest - and shoot eggs into the nest using an ejecting movement of their abdomen.
Species that have a long proboscis can hover over flowers while feeding, much as hummingbirds do, though these flies may touch the flower with their legs for balance while hovering.
Odonata
Odonata is an insect order that includes dragonflies and damselflies. They are strong aviators renowned for their acrobatic flights, including the ability to hover, usually for a short pause during their ceaseless territorial patrols.
Dragonflies
In addition to short hovers while cruising, female dragonflies may hover over the water before or during oviposition, males may also hover-guard their mate at this time.
Damselflies
Some male damselflies hover in front of females or over the oviposition site during courtship; sometimes females also hover in response.
After mating, males may hover-guard their mate by either circling over her or by hovering while attached to her in tandem. Males hover-guarding in tandem do not need wings at all to remain suspended in the air; they are held aloft by clasping their mate with their abdomen, and can maintain their position even when the head and thorax are removed by predators.
Hymenoptera
Bees
Many bee species, such as bumblebees, hover momentarily as they approach flowers to feed.
Males of some species, including carpenter bees and carder bees, also hover while patrolling their territories.
Wasps
Among the social wasps, Stenogastrinae are known as hover wasps due to their distinctive hovering flight.
Males often hover to display banding patterns on their abdomen as a territorial display.
Among the solitary wasps, parasitoid species such as scoliid wasps exhibit hovering behaviour while hunting for prey to feed their larvae.
Males of some parasitoids may hover briefly while they patrol their territories, seeking females and chasing away rivals.
Wind hoverers
Raptors
Many birds of prey such as kestrels, harriers, and members of the Buteo genus can "windhover" by facing the wind.
Elanine kites also engage in "windhovering"; this behaviour is also called "kiting" due the common names of this genus.
Seabirds
Certain seabirds can windhover by soaring or flapping into the wind; often this behaviour takes advantage of thermals whipping off a coastal cliff.
Tropicbirds can even fly backwards against a strong headwind; Red-tailed tropicbird pairs use this ability to circle each other during courtship displays.
Smaller seabirds such as shearwaters and storm petrels feed by hovering low over the water surface,
flapping with half-open wings and paddling with their feet in a technique called "pattering" or "sea-anchoring".
The waves are accompanied by a slight horizontal wind that enables the birds to soar in place while using their feet to steady themselves.
References
Ethology
Bird behavior
Insect behavior | Hover (behaviour) | [
"Biology"
] | 1,041 | [
"Behavior by type of animal",
"Behavior",
"Behavioural sciences",
"Ethology",
"Bird behavior"
] |
75,653,754 | https://en.wikipedia.org/wiki/Olgotrelvir | Olgotrelvir (STI-1558) is an experimental antiviral medication being studied as a potential treatment for COVID-19. It is believed to work by inhibiting the SARS-CoV-2 main protease (Mpro), a key enzyme that SARS-CoV-2 needs to replicate, and by blocking viral entry.
Mechanism of action
Olgotrelvir is a prodrug that first converts to its active form, AC1115. AC1115 is believed to work by inhibiting the SARS-CoV-2 main protease (also known as 3C-like protease). This protein is a crucial enzyme responsible for cleaving viral polyproteins into functional subunits essential for viral replication. By binding to the active site of the protease, the drug prevents this cleavage process, effectively halting viral assembly and impeding the virus's ability to produce future virions.
Olgotrelvir also appears to inhibit cathepsin L (CTSL), a protein implicated in facilitating viral entry of SARS-CoV-2 into the host cell.
Clinical trials
In September 2023, the drug's developer, Sorrento Therapeutics, announced top-line data that olgotrelvir had met its primary endpoints in a phase III clinical trial that enrolled 1,212 patients with mild or moderate COVID-19. The drug appeared to shorten the recovery time of 11 COVID-19 symptoms in olgotrelvir-treated patients by 2.4 days on average compared to patients in the placebo group. The drug was also shown to reduce the viral load at day 4 in treated patients compared to the placebo group. Side effects were mostly mild and infrequent, with the most common being nausea (1.5% vs. 0.2%) and skin rash (3.3% vs. 0.3%), which occurred more often in the olgotrelvir group.
References
COVID-19 drug development
SARS-CoV-2 main protease inhibitors
Indolecarboxamides
Pyrrolidones
Sulfonic acids
Carboxamides
Experimental antiviral drugs | Olgotrelvir | [
"Chemistry"
] | 464 | [
"COVID-19 drug development",
"Functional groups",
"Drug discovery",
"Sulfonic acids"
] |
75,654,215 | https://en.wikipedia.org/wiki/Prabhakar%20function | Prabhakar function is a certain special function in mathematics introduced by the Indian mathematician Tilak Raj Prabhakar in a paper published in 1971. The function is a three-parameter generalization of the well known two-parameter Mittag-Leffler function in mathematics. The function was originally introduced to solve certain classes of integral equations. Later the function was found to have applications in the theory of fractional calculus and also in certain areas of physics.
Definition
The one-parameter and two-parameter Mittag-Leffler functions are defined first. Then the definition of the three-parameter Mittag-Leffler function, the Prabhakar function, is presented. In the following definitions, is the well known gamma function defined by
.
In the following it will be assumed that , and are all complex numbers.
One-parameter Mittag-Leffler function
The one-parameter Mittag-Leffler function is defined as
Two-parameter Mittag-Leffler function
The two-parameter Mittag-Leffler function is defined as
Three-parameter Mittag-Leffler function (Prabhakar function)
The three-parameter Mittag-Leffler function (Prabhakar function) is defined by
where .
Elementary special cases
The following special cases immediately follow from the definition.
, the two-parameter Mittag-Leffler function.
, the one-parameter Mittag-Leffler function.
, the classical exponential function.
Properties
Reduction formula
The following formula can be reduced to lower the value of the third parameter .
Relation with Fox–Wright function
The Prabhakar function is related to the Fox–Wright function by the following relation:
Derivatives
The derivative of the Prabhakar function is given by
There is a general expression for higher order derivatives. Let be a positive integer. The -th derivative of the Prabhakar function is given by
The following result is useful in applications.
Integrals
The following result involving Prabhakar function is known.
Laplace transforms
The following result involving Laplace transforms plays an important role in both physical applications and numerical computations of the Prabhakar function.
Prabhakar fractional calculus
The following function is known as the Prabhakar kernel in the literature.
Given any function , the convolution of the Prabhakar kernel and is called the Prabhakar fractional integral:
Properties of the Prabhakar fractional integral have been extensively studied in the literature.
References
Special functions
Fractional calculus
Integral equations | Prabhakar function | [
"Mathematics"
] | 518 | [
"Special functions",
"Integral equations",
"Calculus",
"Mathematical objects",
"Equations",
"Combinatorics",
"Fractional calculus"
] |
75,655,122 | https://en.wikipedia.org/wiki/Gwadar%20Seawater%20Desalination%20Plant | The Gwadar Seawater Desalination Plant is a desalination project in Gwadar, Pakistan, aimed at meeting water shortages in the city. The plant was established with the support of the Chinese government and is designed to provide clean drinking water to the residents of Gwadar. The desalination plant was inaugurated on 30 June 2023.
Capacity and function
The plant can treat 1.2 million gallons of seawater per day. The water problem in Gwadar city is expected to be solved to a great extent. The plant is operational and supplies 5,000 tonnes of drinking water per day.
Construction and development
The construction of the desalination plant was completed in collaboration with the Gwadar Port Authority and China Harbor Engineering Company. By November 15, 2022, about 30 percent of the construction work had been completed. The pace of work was expected to be completed before April 2023.
The cost of this project was 2 billion rupees, which was financed by the Chinese government.
References
Desalination plants
Water desalination
Infrastructure in Pakistan
China–Pakistan relations | Gwadar Seawater Desalination Plant | [
"Chemistry"
] | 222 | [
"Water treatment",
"Water technology",
"Water desalination"
] |
75,655,509 | https://en.wikipedia.org/wiki/Kuber%20%28tobacco%29 | Kuber is a smokeless tobacco product, known for its highly addictive properties and its unique presentation disguised as a mouth freshener. It originated in India and has gained attention for its widespread use and impact on public health in various countries, including Uganda.
Composition
The product is typically sold in small sachets, with contents resembling tea leaves. This deceptive packaging has contributed to its accessibility and misuse. Kuber is known for its high nicotine content, making it more potent and addictive than traditional cigarettes. Users commonly add it to tea or consume it directly by placing a pinch under the lower lip.
Effects on health
Kuber's high nicotine content raises significant health concerns, including:
Cardiovascular changes
Vascular constriction
Addiction
Cancer
Leukoplakia
Gum damage
Sensory impairment
Tooth loss
Withdrawal from kuber can result in cravings and changes in mood and appetite.
Legal status and regulation
The legal status of kuber varies by region. In some countries, its sale and distribution, especially under the guise of a mouth freshener, have led to legal scrutiny and regulatory measures. For instance, in Uganda, the government has taken steps to ban the use of kuber due to its impact on public health, particularly among youth. The governments of Malawi and Tanzania also banned the manufacture, import, sale, and consumption of kuber. Despite efforts to ban kuber in Kenya, it remains popular, particularly in Nairobi and Mombasa counties.
Societal impact
The widespread use of kuber, especially among young people in high schools and colleges, has raised societal concerns. Its addictive nature and the ease of access have led to a rise in nicotine addiction among adolescents, with implications for long-term public health and social dynamics.
References
Tobacco products
Carcinogens | Kuber (tobacco) | [
"Chemistry",
"Environmental_science"
] | 357 | [
"Carcinogens",
"Toxicology"
] |
75,655,576 | https://en.wikipedia.org/wiki/Gallium%20arsenide%20antimonide | Gallium arsenide antimonide, also known as gallium antimonide arsenide or GaAsSb (GaAs(1-x)Sbx), is a ternary III-V semiconductor compound; x indicates the fractions of arsenic and antimony in the alloy. GaAsSb refers generally to any composition of the alloy. It is an alloy of gallium arsenide (GaAs) and gallium antimonide (GaSb).
Preparation
GaAsSb films have been grown by molecular beam epitaxy (MBE), metalorganic vapor phase epitaxy (MOVPE) and liquid phase epitaxy (LPE) on gallium arsenide, gallium antimonide and indium phosphide substrates. It is often incorporated into layered heterostructures with other III-V compounds.
Thermodynamic Stability
GaAsSb has a miscibility gap at temperatures below 751 °C. This means that intermediate compositions of the alloy below this temperature are thermodynamically unstable and can spontaneously separate into two phases: one GaAs-rich and one GaSb-rich. This limits the compositions of GaAsSb that can be obtained by near-equilibrium growth techniques, such as LPE, to those outside of the miscibility gap. However, compositions of GaAsSb within the miscibility gap can be obtained with non-equilibrium growth techniques, such as MBE and MOVPE. By carefully selecting the growth conditions (e.g., the ratios of precursor gases in MOVPE) and maintaining relatively low temperatures during and after growth, it is possible to obtain compositions of GaAsSb within the miscibility gap that are kinetically stable. For example, this makes it possible to grow GaAsSb with the composition GaAs0.51Sb0.49, which, while normally within the miscibility gap at typical growth temperatures, can exist as a kinetically stable alloy. This composition of GaAsSb is latticed matched to InP and is sometimes used in heterostructures grown on that substrate.
Electronic Properties
The bandgap and lattice constant of GaAsSb alloys are between those of pure GaAs (a = 0.565 nm, Eg = 1.42 eV) and GaSb (a = 0.610 nm, Eg = 0.73 eV). Over all compositions, the band gap is direct, like in GaAs and GaSb. Furthermore, the bandgap displays a minimum in composition at approximately x = 0.8 at T = 300 K, reaching a minimum value of Eg = 0.67 eV, which is slightly below that of pure GaSb.
Applications
GaAsSb has been extensively studied for use in heterojunction bipolar transistors. It has also been lattice-matched with InGaAs on InP to create and study a two-dimensional electron gas.
A GaAsSb/GaAs-based heterostructure was used to make a near-infrared photodiode with peak responsivity centered at 1.3 μm.
GaAsSb can be incorporated into III-V–based multi-junction solar cells to reduce the tunneling distance and increase the tunneling current between adjacent cells.
References
External links
Properties of GaAsSb
Antimonides
Arsenides
Gallium compounds
III-V compounds | Gallium arsenide antimonide | [
"Chemistry"
] | 695 | [
"III-V compounds",
"Inorganic compounds"
] |
75,656,839 | https://en.wikipedia.org/wiki/IBM%20Osprey | IBM Osprey is a 433-qubit quantum processor created by IBM, revealed during the IBM Quantum Summit 2022, which occurred on November 9, 2022, in New York, United States.
It is 3 times larger than its predecessor, the IBM Eagle.
It needs to be cooled down to a temperature of ~0.02 K (-273.13 °C).
References
Quantum computing
IBM microprocessors | IBM Osprey | [
"Technology"
] | 89 | [
"Computing stubs",
"Computer hardware stubs"
] |
75,658,040 | https://en.wikipedia.org/wiki/N-Methyliminodiacetic%20acid | N-Methyliminodiacetic acid is an organic compound with the formula . It is a white solid, which as its conjugate base is used as a chelating agent for iron. It is a component of organoboron reagents as well.
Synthesis and reaction
It is prepared from imidodiacetic acid by N-methylation using the Eschweiler–Clarke reaction:
MIDA boronates are derivatives with the formula , where R is a cross-coupling partner.
Related compounds
Imidodiacetic acid (IDA)
N-(2-Carboxyethyl)iminodiacetic acid
Nitrilotriacetic acid (NTA)
N-Hydroxyiminodiacetic acid (HIDA), (registry number = 87339–38–6). See HIDA scan.
References
Dicarboxylic acids
Chelating agents
Tertiary amines | N-Methyliminodiacetic acid | [
"Chemistry"
] | 189 | [
"Chelating agents",
"Process chemicals"
] |
75,658,705 | https://en.wikipedia.org/wiki/Pentaerythritol%20tetrakis%283-mercaptopropionate%29 | Pentaerythritol tetrakis(3-mercaptopropionate) is an organic compound which is derived from pentaerythritol fully esterified with four equivalents of 3-mercaptopropionic acid. It is a colorless liquid at room temperature.
Uses
Pentaerythritol tetrakis(3-mercaptopropionate) is a common thiol monomer reacted with alkenes in the thiol-ene reaction to form polymeric networks. Being functionalized with four thiol groups, it can react with multifunctional alkenes to form thiol-ene networks.
References
Monomers
Propionate esters
Thiols | Pentaerythritol tetrakis(3-mercaptopropionate) | [
"Chemistry",
"Materials_science"
] | 149 | [
"Organic compounds",
"Monomers",
"Thiols",
"Polymer chemistry"
] |
75,658,720 | https://en.wikipedia.org/wiki/Kalandologion | A kalandologion (Greek καλανδολόγιον, 'almanac'; plural kalandologia) is a type of omen text that purports to predict the effects of the beginning of the year falling on a certain day of the week or in a certain sign of the zodiac. The predictions are meteorological, agricultural, epidemiological, social and political. Kalandologia are found in Greek, Syriac, Mandaic, Ethiopic, Latin, Coptic and Arabic. Before the end of the Middle Ages versions had appeared in many western vernaculars.
The origins of the genre are unclear. Attempts have been made to trace it back to Babylonian astrology or Hellenistic astrology. It is certainly ancient. The Jewish Treatise of Shem probably dates to the first century AD. In the Christian tradition, these texts are most commonly attributed to Ezra. John of Nikiu, writing in Egypt in the sixth century, attests that many Christians used a kalandologion attributed to Ezra. In his Canons, written early in the eighth century, Patriarch Nikephoros I of Constantinople condemns their use, calling them "unclean".
At least three distinct Greek kalandologia survive. The Latin version is known as the Revelatio Esdrae. Its earliest manuscript is from the ninth century. Although usually attributed to Ezra, there is a version misattributed to Bede. The Syriac and Arabic versions are attributed to Daniel and are known from tenth-century manuscripts. In English versions, the name of Ezra has been corruped to "Erra Pater". Vernacular versions attributed to Ezra are known from Old Occitan, Italian, Dutch, German and Czech. The Old French versions, including an Anglo-Norman one that begins the year on Christmas rather than 1 January, are usually attributed to Ezekiel. Many Greek copies are anonymous. The Coptic kalandologion regards the start of the year for prognostic purposes as the sixth of Ṭūba, which corresponded to the first (or kalends) of January, the start of the year in the Roman Empire. Several Coptic kalandologia include a second part that makes predictions based on the strength and direction of the wind in the week of the sixth of Ṭūba. The fragmentary Coptic kalandologion in the 9th-century papyrus P.Mich. inv. 590 is of the latter type, for example:
If the east wind comes on 8 Tubi, there will be a great winter, the weather will be good, the cattle will miscarry, the wheat will become as dry as cumin, the men will suffer severe illnesses, and the children will die.
If a south wind comes forth on the dawn of 9 Tubi, and the north winds comes forth at evening, it means a great summer, the crops will increase, the small livestock will miscarry but will not continue (to do so), and the honey will become profitable.
References
Further reading
Wilfong, Terry G. "Agriculture among the Christian Population of Early Islamic Egypt: Practice and Theory." In Alan K. Bowman and E. Rogan (eds.), Agriculture in Egypt from Pharaonic to Modern Times. Oxford University Press, 1999. pp. 217–236.
Divination
History of astrology | Kalandologion | [
"Astronomy"
] | 690 | [
"History of astrology",
"History of astronomy"
] |
75,659,158 | https://en.wikipedia.org/wiki/DBOS | DBOS (Database-Oriented Operating System) is a database-oriented operating system meant to simplify and improve the scalability, security and resilience of large-scale distributed applications. It started in 2020 as a joint open source project with MIT, Stanford and Carnegie Mellon University, after a brainstorm between Michael Stonebraker and Matei Zaharia on how to scale and improve scheduling and performance of millions of Apache Spark tasks.
The basic idea is to run a multi-node multi-core, transactional, highly-available distributed database, such as VoltDB, as the only application for a microkernel, and then to implement scheduling, messaging, file systems and other operating system services on top of the database.
The architectural philosophy is described by this quote from the abstract of their initial preprint: All operating system state should be represented uniformly as database tables, and operations on this state should be made via queries from otherwise stateless tasks. This design makes it easy to scale and evolve the OS without whole-system refactoring, inspect and debug system state, upgrade components without downtime, manage decisions using machine learning, and implement sophisticated security features.Stonebraker claims a variety of security benefits, from a "smaller, less porous attack surface", to the ability to log and analyze how the system state changes in real-time due to the transactional nature of the OS. Recovery from a severe bug or an attack can be as simple as rolling back the database to a previous state. And since the database is already distributed, the complexity of orchestration systems like Kubernetes can be avoided.
A prototype was built with competitive performance to existing systems.
DBOS Cloud
In March of 2024, DBOS Cloud became the first commercial service from DBOS Inc. It provides transactional Functions as a Service (FaaS), and is positioned as a competitor to serverless computing architectures like AWS Lambda. DBOS Cloud is currently based on FoundationDB, a fast ACID NoSQL database, running on the Firecracker service from AWS. It provides built-in support for features like multinode scaling and a "time-traveler" debugger that can help track down elusive heisenbugs and works in Visual Studio Code. Another feature is reliable execution, allowing a program to continue running even if the operating system needs to be restarted, and ensuring that no work is repeated.
Firecracker runs on stripped down Linux microkernel via a stripped down KVM hypervisor, so parts of the Linux kernel are still under the covers, but work is ongoing to eliminate them.
DBOS Cloud has been tested running across 1,000 cores running applications. The first API provided is for TypeScript, via the open-source DBOS Transact framework. It provides a runtime with built-in reliable message delivery and idempotency.
Holger Mueller of Constellation Research wondered how well DBOS the company can scale. “Will a small team at DBOS be able to run an OS, database, observability, workflow and cyber stack as good as the combination of the best of breed vendors?”
See also
PICK OS, another implementation of an operating system based on a DB.
References
External links
Operating systems | DBOS | [
"Technology"
] | 670 | [
"Operating system stubs",
"Computing stubs"
] |
75,659,247 | https://en.wikipedia.org/wiki/Beibei%20Wang%20%28engineer%29 | Beibei Wang (born 1983) is a Chinese-American electrical engineer known for her research in wireless sensor networks, cognitive radio, and the use of cooperative game theory in wireless communication. She is vice president for research at Origin Wireless, Inc.
Education and career
Wang earned a bachelor's degree in electrical engineering in 2004 from the University of Science and Technology of China. She completed her Ph.D. at the University of Maryland, College Park, in 2009. Her doctoral dissertation, Dynamic Spectrum Allocation and Sharing in Cognitive Cooperative Networks, was supervised by K. J. Ray Liu.
After postdoctoral research at the University of Maryland, she worked for Qualcomm from 2010 to 2014. In 2015, she joined Origin Wireless, which her advisor had founded in 2013.
Books
Wang is the coauthor of
Cognitive Radio Networking and Security: A Game-Theoretic View (2010)
Wireless AI: Wireless Sensing, Positioning, IoT, and Communications (2019)
Recognition
Wang was named an IEEE Fellow, in the 2024 class of fellows, "for contributions to wireless sensing and cognitive communications".
References
External links
Home page
1983 births
Living people
Chinese electrical engineers
21st-century Chinese women engineers
21st-century Chinese engineers
American electrical engineers
American women engineers
Women electrical engineers
Game theorists
University of Science and Technology of China alumni
University of Maryland, College Park alumni
Fellows of the IEEE | Beibei Wang (engineer) | [
"Mathematics"
] | 276 | [
"Game theorists",
"Game theory"
] |
75,659,300 | https://en.wikipedia.org/wiki/Metamerism%20%28chemistry%29 | In chemistry, metamerism is used to define the isomeric relationship between compounds with the same polyvalent, heteroatomic, functional group but differ in the main carbon chain or any of the side chains. It has rather been an obsolete term for isomerism, which has not been recognised by IUPAC in its publications. When Swedish chemist Jöns Jacob Berzelius used the term in 1831, he did so to describe those substances which possess the same percentage composition but had different properties. What Berzelius implied to be called metamerism is now considered as isomerism.
Examples
The isomers which have been cited as examples of metamers in chemical literature consist primarily of ethers; but this could by the same reasoning be extended to thioethers, secondary as well as tertiary amines, esters, secondary as well as tertiary amides, (mixed) acid anhydrides etc.
Ketones however, should be excluded from this class of isomeric relationship, as they primarily are part of position isomerism - as there is no heteroatom present in the functional group, so the two alkyl groups (main chain and side chain) are not disconnected from each other.
Textbook Use
There have been disputes on metamerism being included with other isomerisms such as position as well as chain isomerism, some authors still keep using it in their textbooks, mostly citing the examples of ethers and secondary amines.
See also
Stereoisomer
Structural isomer
Tautomers
References
External links
Isomerism | Metamerism (chemistry) | [
"Chemistry"
] | 318 | [
"Isomerism",
"Stereochemistry"
] |
71,337,033 | https://en.wikipedia.org/wiki/Praseodymium%20orthoscandate | Praseodymium orthoscandate is a chemical compound, a rare-earth oxide with a perovskite structure. It has the chemical formula of PrScO3.
Preparation
Praseodymium orthoscandate can be obtained by reacting praseodymium(III,IV) oxide with scandium oxide.
Properties
Praseodymium orthoscandate is a green solid. It has an orthorhombic perovskite-type crystal structure with space group Pnma (space group No. 62).
In 2021, with the help of electron ptychography, researchers were able to achieve the highest magnification. In this way, the researchers managed to enlarge the atoms of a praseodymium orthoscandate crystal by a factor of 100 million.
See also
Praseodymium
Scandium
Oxygen
References
Praseodymium(III) compounds
Scandium compounds
Oxides | Praseodymium orthoscandate | [
"Chemistry"
] | 198 | [
"Oxides",
"Salts"
] |
71,337,783 | https://en.wikipedia.org/wiki/N%20%3D%201%20supersymmetric%20Yang%E2%80%93Mills%20theory | In theoretical physics, more specifically in quantum field theory and supersymmetry, supersymmetric Yang–Mills, also known as super Yang–Mills and abbreviated to SYM, is a supersymmetric generalization of Yang–Mills theory, which is a gauge theory that plays an important part in the mathematical formulation of forces in particle physics. It is a special case of 4D N = 1 global supersymmetry.
Super Yang–Mills was studied by Julius Wess and Bruno Zumino in which they demonstrated the supergauge-invariance of the theory and wrote down its action, alongside the action of the Wess–Zumino model, another early supersymmetric field theory.
The treatment in this article largely follows that of Figueroa-O'Farrill's lectures on supersymmetry and of Tong.
While N = 4 supersymmetric Yang–Mills theory is also a supersymmetric Yang–Mills theory, it has very different properties to supersymmetric Yang–Mills theory, which is the theory discussed in this article. The supersymmetric Yang–Mills theory was studied by Seiberg and Witten in Seiberg–Witten theory. All three theories are based in super Minkowski spaces.
The supersymmetric Yang–Mills action
Preliminary treatment
A first treatment can be done without defining superspace, instead defining the theory in terms of familiar fields in non-supersymmetric quantum field theory.
Spacetime and matter content
The base spacetime is flat spacetime (Minkowski space).
SYM is a gauge theory, and there is an associated gauge group to the theory. The gauge group has associated Lie algebra .
The field content then consists of
a -valued gauge field
a -valued Majorana spinor field (an adjoint-valued spinor), known as the 'gaugino'
a -valued auxiliary scalar field .
For gauge-invariance, the gauge field is necessarily massless. This means its superpartner is also massless if supersymmetry is to hold. Therefore can be written in terms of two Weyl spinors which are conjugate to one another: , and the theory can be formulated in terms of the Weyl spinor field instead of .
Supersymmetric pure electromagnetic theory
When , the conceptual difficulties simplify somewhat, and this is in some sense the simplest gauge theory. The field content is simply a (co-)vector field , a Majorana spinor and a auxiliary real scalar field .
The field strength tensor is defined as usual as .
The Lagrangian written down by Wess and Zumino is then
This can be generalized to include a coupling constant , and theta term , where is the dual field strength tensor
and is the alternating tensor or totally antisymmetric tensor. If we also replace the field with the Weyl spinor , then a supersymmetric action can be written as
This can be viewed as a supersymmetric generalization of a pure gauge theory, also known as Maxwell theory or pure electromagnetic theory.
Supersymmetric Yang–Mills theory (preliminary treatment)
In full generality, we must define the gluon field strength tensor,
and the covariant derivative of the adjoint Weyl spinor,
To write down the action, an invariant inner product on is needed: the Killing form is such an inner product, and in a typical abuse of notation we write simply as , suggestive of the fact that the invariant inner product arises as the trace in some representation of .
Supersymmetric Yang–Mills then readily generalizes from supersymmetric Maxwell theory. A simple version is
while a more general version is given by
Superspace treatment
Superspace and superfield content
The base superspace is super Minkowski space.
The theory is defined in terms of a single adjoint-valued real superfield , fixed to be in Wess–Zumino gauge.
Supersymmetric Maxwell theory on superspace
The theory is defined in terms of a superfield arising from taking covariant derivatives of :
.
The supersymmetric action is then written down, with a complex coupling constant , as
where h.c. indicates the Hermitian conjugate of the preceding term.
Supersymmetric Yang–Mills on superspace
For non-abelian gauge theory, instead define
and . Then the action is
Symmetries of the action
Supersymmetry
For the simplified Yang–Mills action on Minkowski space (not on superspace), the supersymmetry transformations are
where .
For the Yang–Mills action on superspace, since is chiral, then so are fields built from . Then integrating over half of superspace, , gives a supersymmetric action.
An important observation is that the Wess–Zumino gauge is not a supersymmetric gauge, that is, it is not preserved by supersymmetry. However, it is possible to do a compensating gauge transformation to return to Wess–Zumino gauge. Then, after a supersymmetry transformation and the compensating gauge transformation, the superfields transform as
Gauge symmetry
The preliminary theory defined on spacetime is manifestly gauge invariant as it is built from terms studied in non-supersymmetric gauge theory which are gauge invariant.
The superfield formulation requires a theory of generalized gauge transformations. (Not supergauge transformations, which would be transformations in a theory with local supersymmetry).
Generalized abelian gauge transformations
Such a transformation is parametrized by a chiral superfield , under which the real superfield transforms as
In particular, upon expanding and appropriately into constituent superfields, then contains a vector superfield while contains a scalar superfield , such that
The chiral superfield used to define the action,
is gauge invariant.
Generalized non-abelian gauge transformations
The chiral superfield is adjoint valued. The transformation of is prescribed by
,
from which the transformation for can be derived using the Baker–Campbell–Hausdorff formula.
The chiral superfield is not invariant but transforms by conjugation:
,
so that upon tracing in the action, the action is gauge-invariant.
Extra classical symmetries
Superconformal symmetry
As a classical theory, supersymmetric Yang–Mills theory admits a larger set of symmetries, described at the algebra level by the superconformal algebra. Just as the super Poincaré algebra is a supersymmetric extension of the Poincaré algebra, the superconformal algebra is a supersymmetric extension of the conformal algebra which also contains a spinorial generator of conformal supersymmetry .
Conformal invariance is broken in the quantum theory by trace and conformal anomalies.
While the quantum supersymmetric Yang–Mills theory does not have superconformal symmetry, quantum N = 4 supersymmetric Yang–Mills theory does.
R-symmetry
The R-symmetry for supersymmetry is a symmetry of the classical theory, but not of the quantum theory due to an anomaly.
Adding matter
Abelian gauge
Matter can be added in the form of Wess–Zumino model type superfields . Under a gauge transformation,
,
and instead of using just as the Lagrangian as in the Wess–Zumino model, for gauge invariance it must be replaced with
This gives a supersymmetric analogue to QED. The action can be written
For flavours, we instead have superfields , and the action can be written
with implicit summation.
However, for a well-defined quantum theory, a theory such as that defined above suffers a gauge anomaly. We are obliged to add a partner to each chiral superfield (distinct from the idea of superpartners, and from conjugate superfields), which has opposite charge. This gives the action
Non-Abelian gauge
For non-abelian gauge, matter chiral superfields are now valued in a representation of the gauge group:
.
The Wess–Zumino kinetic term must be adjusted to .
Then a simple SQCD action would be to take to be the fundamental representation, and add the Wess–Zumino term:
.
More general and detailed forms of the super QCD action are given in that article.
Fayet–Iliopoulos term
When the center of the Lie algebra is non-trivial, there is an extra term which can be added to the action known as the Fayet–Iliopoulos term.
References
Supersymmetric quantum field theory | N = 1 supersymmetric Yang–Mills theory | [
"Physics"
] | 1,766 | [
"Supersymmetric quantum field theory",
"Supersymmetry",
"Symmetry"
] |
71,338,679 | https://en.wikipedia.org/wiki/A%20People%27s%20History%20of%20Computing%20in%20the%20United%20States | A People’s History of Computing in the United States is a non-fiction book by Joy Lisi Rankin. It focuses on American students and educators in the 1960s and 1970s, in particular, those at Dartmouth College, in the Minnesota education system, and at the University of Illinois. Rankin is especially interested in countering the "Silicon Valley mythology" and showing how "computing citizens" created their own networks and fostered a sense of computing for the public good, which she compares to today's "computing consumers".
References
External links
(Adapted excerpt from the book)
Press website
Technology books | A People's History of Computing in the United States | [
"Technology"
] | 121 | [
"Computing stubs",
"Computer book stubs"
] |
71,342,006 | https://en.wikipedia.org/wiki/Samsung%20Galaxy%20Watch%205 | The Samsung Galaxy Watch 5 (stylized as Samsung Galaxy Watch5) is a series of Wear OS-based smartwatches developed by Samsung Electronics. It was announced on 10 August 2022, and was released on 26 August 2022.
Specifications
References
External links
Consumer electronics brands
Products introduced in 2022
Smartwatches
Samsung wearable devices
Watch 5
Wear OS devices | Samsung Galaxy Watch 5 | [
"Technology"
] | 73 | [
"Wear OS devices",
"Smartwatches"
] |
71,342,728 | https://en.wikipedia.org/wiki/Standardised%20Precipitation%20Evapotranspiration%20Index | The Standardized Precipitation Evapotranspiration Index (SPEI) is a multiscalar drought index based on climatic data. It was developed by Vicente-Serrano et al. (2010) at the Institute Pirenaico de Ecologia in Zaragoza, Spain. It can be used for determining the onset, duration and magnitude of drought conditions with respect to normal conditions in a variety of natural and managed systems such as crops, ecosystems, rivers, water resources, etc.
The SPEI accounts not only for precipitation deficit but also for the role of the increased atmospheric evaporative demand on drought severity. Evaporative demand is particularly dominant during periods of precipitation deficit. The SPEI calculation requires long-term and high-quality precipitation and atmospheric evaporative demand datasets. These can be obtained from ground stations or gridded data based on reanalysis as well as satellite and multi-source datasets.
Datasets
Globally, the SPEIbase and Global Precipitation Climatology Centre (GPCC) drought index datasets are available at a relatively coarse spatial resolution. The SPEIbase is available at 0.5° resolution calculated from the Climatic Research Unit precipitation and potential evapotranspiration datasets. The GPCC drought index provides SPEI datasets at a 1.0° spatial resolution for limited timescales (1, 3, 6, 9, 12, 24, and 48 months).
Inputs to SPEI datasets can include high-resolution potential evapotranspiration (PET) from the Global Land Evaporation Amsterdam Model (GLEAM) and hourly Potential Evapotranspiration (hPET). GLEAM is a set of algorithms designed to calculate actual evaporation, PET, evaporative stress, and root-zone soil moisture.
Classification
See also
Keetch–Byram drought index
Palmer drought Index
References
External links
SPEI world database, updated monthly
R package that calculates the SPEI
Meteorological indices
Droughts
Hydrology | Standardised Precipitation Evapotranspiration Index | [
"Chemistry",
"Engineering",
"Environmental_science"
] | 409 | [
"Hydrology",
"Hydrology stubs",
"Environmental engineering"
] |
71,344,906 | https://en.wikipedia.org/wiki/Interactive%20application%20security%20testing | Interactive application security testing (abbreviated as IAST) is a security testing method that detects software vulnerabilities by interaction with the program coupled with observation and sensors. The tool was launched by several application security companies. It is distinct from static application security testing, which does not interact with the program, and dynamic application security testing, which considers the program as a black box. It may be considered a mix of both.
References
Security testing | Interactive application security testing | [
"Technology"
] | 90 | [
"Computer security stubs",
"Computing stubs"
] |
71,345,296 | https://en.wikipedia.org/wiki/Leucocoprinus%20griseofloccosus | Leucocoprinus griseofloccosus is a species of mushroom producing fungus in the family Agaricaceae.
Taxonomy
It was first described in 2018 by the French mycologists Vincent Lagardère & Guillaume Eyssartier from specimens found in 2017 in Mouréou, Arengosse in the South West Landes region of France. It was noted to be similar in appearance to Leucocoprinus cygneus with previous observations likely being confused with this species however it is differentiated from it by the grey flaky cap whilst L. cygneus is described as pure white and powdery.
Description
Leucocoprinus griseofloccosus is a small dapperling mushroom with thin white flesh.
Cap: Up to 1 cm. Quickly opens to convex with a very slight white or greyish umbo. Stem: 0.5-1.5 x 0.1-0.2 cm. Wider at the base. White with a thin stem ring that is tinged with grey at the edges. Gills: White, crowded, free with a powdery edge. Spores: Elliptical with a tiny germ pore. Dextrinoid. 5.5 - 6.3 x 3.3 - 3.8 μm. Smell: Faint.
Habitat and distribution
The specimens in France were found growing within rotting alder trunks beside a stream in mixed woodland. The woodland was located on clay rich soil within an ericaceous heath.
In November 2019 it was found in the UK for the first time with specimens observed to be growing in rotten Douglas fir logs at the New Forest Reptile Centre near Lyndhurst, South Hampshire. Another observation was made in October 2020 on rotting pine logs in Marlhill copse near Southampton airport.
Etymology
The specific epithet griseofloccosus is derived from the Latin griseus meaning grey and floccosus meaning flaky. This is a reference to the colour and texture of the veil.
Similar species
Leucocoprinus cygneus
References
Leucocoprinus
Fungi described in 2018
Fungi of Europe
Fungus species | Leucocoprinus griseofloccosus | [
"Biology"
] | 430 | [
"Fungi",
"Fungus species"
] |
71,345,347 | https://en.wikipedia.org/wiki/Hermann%20Josef%20Schnell | Hermann Schnell ( 16. September March 1916 – 7 September 1999) was a German organic chemist who developed the first commercial polycarbonate, Makrolon.
Hermann Schnell studied chemistry at the University of Freiberg. His supervisor was Hermann Staudinger a well-known polymer chemist.
After his phd he worked in the research laboratory of the Bayer AG in Uerdingen, starting in 1946. In 1953 he developed the synthesis of polycarbonates by reacting phosgene with bisphenol A. This material marketed as Makrolon was a commercial success.
References
1916 births
1999 deaths
Academic staff of the University of Freiburg
20th-century German chemists
German organic chemists
Polymer scientists and engineers | Hermann Josef Schnell | [
"Chemistry"
] | 149 | [
"Organic chemists",
"German organic chemists"
] |
71,345,884 | https://en.wikipedia.org/wiki/Leucocoprinus%20cygneus | Leucocoprinus cygneus is a species of mushroom producing fungus in the family Agaricaceae.
Taxonomy
It was first described in 1940 by the Danish mycologist Jakob Emanuel Lange who classified it as Lepiota cygnea until 1952 when it was classified as Pseudobaeospora cygnea by the French mycologist Marcel Locquin.
In 1978 the Belgian mycologist Paul Heinemann created the new genus Sericeomyces in an attempt to better arrange the species which are now recognised as belonging to the Lepiota, Leucoagaricus and Leucocoprinus genera. He reclassified this species as Sericeomyces cygneus but noted that placing it in this newly created genus was questionable. This proposed placement turned out to be short lived as it was also in 1978 that Austrian mycologist Meinhard Michael Moser classified it as Cystolepiota cygnea and the French mycologist Marcel Bon classified it as Leucocoprinus cygneus, which was ultimately the classification which was adopted.
Description
Leucocoprinus cygneus is a small dapperling mushroom with thin white flesh and a white, powdery cap.
Cap: 1.5–2 cm. Campanulate and expanding as it matures. Pure white and slightly silky. Stem: 3 cm tall by 2mm in thickness. Hollow and smooth with a ring. Gills: White, narrow, crowded and free. Spores: Ellipsoid with a tiny germ pore. Dextrinoid. 6.5 x 3.5 μm.
Etymology
The specific epithet cygneus (originally cygnea) derives from the Latin for cygnus meaning swan. This is in reference to the 'swan-like' colour of the cap.
Habitat and distribution
This species is rarely recorded. In the UK only two collections of L cygneus have been documented with one specimen in Kew's collection which was found in West Norfolk and a second in a collection in Edinburgh from a specimen found in South Devon. The first was found growing inside a hollow tree trunk whilst the second was found on damp ground. It is now speculated that the specimen found on the rotting wood may be Leucocoprinus griseofloccosus instead.
Similar species
Leucocoprinus griseofloccosus
References
Leucocoprinus
Fungi described in 1940
Taxa named by Marcel Locquin
Fungus species | Leucocoprinus cygneus | [
"Biology"
] | 502 | [
"Fungi",
"Fungus species"
] |
71,346,490 | https://en.wikipedia.org/wiki/GLASS-z12 | GLASS-z12 (formerly known as GLASS-z13) is a Lyman-break galaxy discovered by the Grism Lens-Amplified Survey from Space (GLASS) observing program using the James Webb Space Telescope's NIRCam in July 2022. Spectroscopic observations of GLASS-z12 by the Atacama Large Millimeter Array (ALMA) in August 2022 confirmed that the galaxy has a spectroscopic redshift of , making it one of the earliest and most distant galaxies ever discovered, dating back to just 350 million years after the Big Bang, 13.6 billion years ago. ALMA observations detected an emission line associated with doubly ionized oxygen (O III) at 258.7 GHz with a significance of 5σ, suggesting that there is very low dust content in GLASS-z12, if not the early universe as well. Also based on oxygen-related measurements, the age of the galaxy is confirmed.
GLASS-z12 derives its name from the GLASS survey that discovered it and its estimated photometric redshift of approximately z = . GLASS-z12 was initially announced as GLASS-z13 because it was thought to have a higher redshift of z = 13.1. This redshift value was later revised down to z = 12.4 in October 2022, resulting in the renaming of this galaxy.
GLASS-z12 has a light-travel distance (lookback time) of 13.6 billion years. However, due to the expansion of the universe, its present proper distance is 33.2 billion light-years. It was discovered alongside another galaxy, GLASS-z10, comparable to GN-z11, also one of the oldest galaxies discovered.
See also
CEERS-93316
Earliest galaxies
HD1 (galaxy)
JADES-GS-z13-0
List of the most distant astronomical objects
References
Galaxies
Sculptor (constellation)
Dwarf galaxies
Discoveries by the James Webb Space Telescope | GLASS-z12 | [
"Astronomy"
] | 396 | [
"Constellations",
"Sculptor (constellation)"
] |
71,347,515 | https://en.wikipedia.org/wiki/List%20of%20bridges%20known%20for%20strikes | This is a list of bridges and overpasses whose low clearance causes a notable amount of accidents, also known as bridge strikes. Simply being struck by a vehicle is not criteria for inclusion on this list. To be included, the bridge should have a notable history of strikes.
Many countries establish minimum standards for the structure gauge of bridges. For example, the United States requires a height of 14 feet (4.27 m) for highway bridges. Some vehicle standards are made to conform to these expectations. In much of the United States, the maximum height of a semi truck, in the absence of an approved overheight permit, is 13 feet, 6 inches (4.12 m). Some bridges were built before the adoption of these standards, and are undersized. Accidents involving these bridges have spurred mitigation efforts, such as installing sensors and signs that warn drivers. These efforts do not entirely eliminate strikes, prompting some efforts to increase the clearance height.
Viral videos of bridge strikes have generated substantial public interest. One of the most famous examples of this is the Norfolk Southern–Gregson Street Overpass, also known as the "11foot8" bridge, which was popularized by a YouTube channel.
Bridges
The bridges are listed in no particular order.
References
Strikes
Road hazards
\ | List of bridges known for strikes | [
"Technology"
] | 260 | [
"Road hazards"
] |
71,349,156 | https://en.wikipedia.org/wiki/Sergei%20Netyosov | Sergei Viktorovich Netyosov () is a Russian molecular biologist, a specialist in virus genomes.
Biography
Sergei Netyosov was born on April 19, 1953, in Leninsk-Kuznetsky, Kemerovo Oblast.
In 1975 he graduated from the Faculty of Natural Sciences at the Novosibirsk State University.
In 1975–1977 he worked at the Vorozhtsov Novosibirsk Institute of Organic Chemistry as a trainee researcher. From 1977 to 2007 he was an employee of the All-Russian Research Institute of Molecular Biology of the Glavmikrobioprom (In 1986, the organization was included in the Vector Institute).
Netyosov has been living in Koltsovo since 1980.
Since 1994 he has lectured at Novosibirsk State University.
Scientific activity
The scientist studies the genomes of human and animal viruses, viral proteins and participates in the development of antiviral vaccines.
He conducted research on the identification and analysis of the primary structures of a number of strains of influenza virus subtypes H1N1 and H5N1, Marburg and Ebola viruses, strain 205 of tick-borne encephalitis virus, hepatitis viruses A, B, C, E and G; revealed the presence of immunosuppressive domains in the genomes of filoviruses; conducted a large complex of works on accurate mapping of antigenic determinants of influenza and Venezuelan equine encephalomyelitis viruses etc.
The laboratory of a scientist, for example, is studying the mechanisms of filovirus replication based on a constructed mini-replicon of the Marburg virus.
The researcher has over 170 publications in Scopus, his h-index is 27.
Sergei Netyosov is a member of the Voprosy Virusologii Magazine editorial board.
References
Living people
1953 births
Molecular biologists
Novosibirsk State University alumni
Academic staff of Novosibirsk State University
Scientists from Novosibirsk
20th-century Russian biologists
People from Leninsk-Kuznetsky
21st-century Russian biologists | Sergei Netyosov | [
"Chemistry"
] | 428 | [
"Biochemists",
"Molecular biology",
"Molecular biologists"
] |
71,349,307 | https://en.wikipedia.org/wiki/2022%20California%20Proposition%2030 | Proposition 30 is a California ballot proposition that appeared in the general election on November 8, 2022. The measure was defeated. The initiative would have raised taxes on the wealthy to fund wildfire management and electric vehicle (and ZEV) incentives and infrastructure.
A "yes" vote supported the tax increase on income above $2 million; a "no" vote supported maintaining the current tax rate for people of this income.
Proposal
The initiative would have raised taxes by 1.75% on annual personal income in excess of $2 million and directed 45% of the revenue to incentives, 35% to charging stations, and 20% to wildfire prevention. The tax revenue the proposal would have generated was estimated to be between $3 and $4.5 billion annually. The tax would have sunset in 2043, or after California achieved a reduction in greenhouse gas (GHG) emissions of 80% below 1990 levels, whichever was earlier.
Wildfires and gas combustion contribute to air pollution and release greenhouse gases, so these measures could have improved air quality and contributed to climate mitigation. It would have combated wildfires by increasing the budget for the California Department of Forestry and Fire Protection by up to $1 billion annually.
Support and opposition
The campaign for Proposition 30 was mostly funded by the rideshare company Lyft, which could have used the incentives to facilitate compliance with the state's electric vehicle requirements. Specifically, ride-hailing companies are required by the state to log 90 percent of their miles in electric vehicles by 2030, and the proposition could have increased the number of drivers with electric vehicles. By April 2022, Lyft had already spent $8 million in support of the proposition. It was also supported by the California Democratic Party, California Environmental Voters, the State Building and Construction Trades Council of California, and the California State Association of Electrical Workers. It was supported by Representatives Ro Khanna and Barbara Lee, and mayors Sam Liccardo and Libby Schaaf. Environmental and transportation experts argued that Proposition 30 is necessary because the state's prior investments in electrification were insufficient.
The proposition was opposed by the California Republican Party, the California Teachers Association, the California Chamber of Commerce, and the Howard Jarvis Taxpayers Association. Governor Gavin Newsom also criticized Lyft, saying that the proposition was "a cynical scheme devised by a single corporation to funnel state income tax revenue to their company", noting that the state had already committed $10 billion for electric vehicles and their infrastructure. The campaign against Proposition 30 also produced a TV ad featuring Newsom, where he argued that the initiative was "a trojan horse that puts corporate welfare above the fiscal welfare of our entire state". The biggest donors to the opposition campaign were hedge fund manager William S. Fisher and billionaire Michael Moritz, and investment firm founder Mark Heising.
Environmental policy experts such as Bill Magavern of the Coalition for Clean Air refuted the governor's claims, clarifying that nothing in the measure directed money specifically to Lyft. “It doesn’t take money from any other purpose. This is money that otherwise would just be in the pockets of really rich people,” he said. “And I think when you’re talking about motives, you got to look who’s funding the governor’s attack: really rich people.” For this reason, Joe Garofoli of the San Francisco Chronicle alleged that Newsom opposed the measure to further his presidential ambitions. The measure's ultimate failure was widely attributed to Newsom's opposition.
Polling
Notes
References
Climate change adaptation
Emissions reduction
Electric vehicles in California
Wildfires in California
2022 California ballot propositions | 2022 California Proposition 30 | [
"Chemistry"
] | 737 | [
"Greenhouse gases",
"Emissions reduction"
] |
71,350,420 | https://en.wikipedia.org/wiki/Gauss%20separation%20algorithm | Carl Friedrich Gauss, in his treatise Allgemeine Theorie des Erdmagnetismus, presented a method, the Gauss separation algorithm, of partitioning the magnetic field vector, B, measured over the surface of a sphere into two components, internal and external, arising from electric currents (per the Biot–Savart law) flowing in the volumes interior and exterior to the spherical surface, respectively. The method employs spherical harmonics. When radial currents flow through the surface of interest, the decomposition is more complex, involving the decomposition of the field into poloidal and toroidal components. In this case, an additional term (the toroidal component) accounts for the contribution of the radial current to the magnetic field on the surface.
The method is commonly used in studies of terrestrial and planetary magnetism, to relate measurements of magnetic fields either at the planetary surface or in orbit above the planet to currents flowing in the planet's interior (internal currents) and its magnetosphere (external currents). Ionospheric currents would be exterior to the planet's surface, but might be internal currents from the vantage point of a satellite orbiting the planent.
Notes
References
.
.
Magnetism
Geomagnetism
Physical quantities
Harmonic analysis | Gauss separation algorithm | [
"Physics",
"Materials_science",
"Mathematics"
] | 251 | [
"Materials science stubs",
"Physical phenomena",
"Physical quantities",
"Quantity",
"Physical properties",
"Electromagnetism stubs"
] |
71,350,555 | https://en.wikipedia.org/wiki/MMSAT-1 | MMSAT-1 (also known as Lawkanat-1) was a Burmese microsatellite launched to the International Space Station (ISS) on 20 February 2021 and deployed into orbit from the ISS on 22 March 2021. It was Myanmar's first microsatellite and jointly built by Japan's Hokkaido University and Myanmar Aerospace Engineering University. It was delivered to the ISS by the American cargo spacecraft Cygnus NG-15. MMSAT-1 was temporarily held on ISS and its deployment was delayed due to the 2021 Myanmar coup d'état. It was deployed into orbit on 22 March 2021.
MMSAT-1 was intended to be used not only for environmental observation and mineral exploration, but also for natural disaster control, but human rights activists worried that the satellite could be used for military purposes. According to Hokkaido University, as Myanmar did not yet have the necessary equipment, the satellite would initially be operated from Japan.
MMSAT-1 reentered the atmosphere on 4 April 2023.
References
Earth observation satellites
Satellites of Myanmar
2021 in Myanmar
Spacecraft launched in 2021
Spacecraft which reentered in 2023
Satellites deployed from the International Space Station | MMSAT-1 | [
"Astronomy"
] | 233 | [
"Outer space stubs",
"Astronomy stubs",
"Outer space"
] |
71,351,682 | https://en.wikipedia.org/wiki/List%20of%20existing%20technologies%20predicted%20in%20science%20fiction | This list of existing technologies predicted in science fiction includes every medium, mainly literature and film. In 1964 Soviet engineer and writer Genrikh Altshuller made the first attempt to catalogue science fiction technologies of the time.
Alongside first prediction of a particular technology, the list may include all subsequent works mentioning it until its invention. The list includes technologies that were first posited in non-fiction works before their appearance in science fiction and subsequent invention, such as ion thruster. To avoid repetitions, the list excludes film adaptations of prior literature containing the same predictions, such as "The Minority Report". The list also excludes emerging technologies that are not widely available. The names of some modern inventions (atomic bomb, credit card, robot, space station, oral contraceptive and borazon) exactly match their fictional predecessors. A few works correctly predicted the years when some technologies would emerge, such as the first sustained heavier-than-air aircraft flight in 1903 and the first atomic bomb explosion in 1945.
Literature
Films and TV series
Notes
References
Sources
See also
Clarke's three laws
List of emerging technologies
List of hypothetical technologies
Materials science in science fiction
Prophets of Science Fiction
Prediction
existing technologies predicted in science fiction
existing technologies predicted in science fiction
existing technologies predicted in science fiction
History of technology | List of existing technologies predicted in science fiction | [
"Technology"
] | 259 | [
"Science and technology studies",
"History of science and technology",
"History of technology"
] |
71,351,866 | https://en.wikipedia.org/wiki/Cerium%28IV%29%20perchlorate | Cerium(IV) perchlorate is an inorganic compound composed of cerium and perchloric acid. It has the chemical formula of Ce(ClO4)4.
Uses
Cerium(IV) perchlorate is used as a catalyst in organic chemistry for the determination of strontium and for cerimetry. It has a very high redox potential at Ce4+/Ce3+ of +1.87 V in 8 M HClO4.
References
Cerium compounds
Perchlorates | Cerium(IV) perchlorate | [
"Chemistry"
] | 105 | [
"Salts",
"Inorganic compounds",
"Perchlorates",
"Inorganic compound stubs"
] |
71,354,355 | https://en.wikipedia.org/wiki/Hiroshi%20Suura | Hiroshi Suura (born August 19, 1925, Hiroshima, Japan – September 15, 1998) was a Japanese theoretical physicist, specializing in particle physics.
Education and career
Suura graduated in 1947 with a B.S. from the University of Tokyo and in 1954 with a Ph.D. in physics from Hiroshima University. From September 1955 to June 1956 he did research at the Institute for Advanced Study. From 1960 to 1965 he was a professor at Nihon University. From 1965 until his retirement as professor emeritus, he was a professor at the University of Minnesota.
In the theory of infrared corrections, Suura made important contributions, essential for many precise measurements involving elementary particles, especially electrons.
He was elected in 1967 a Fellow of the American Physical Society. On June 1, 1994, the University of Minnesota held a colloquium in honor of Hiroshi Suura. After his death, the Physical Society of Japan published a collection of articles as a memorial to him.
Selected publications
(over 1900 citations)
References
1925 births
1998 deaths
20th-century Japanese physicists
Particle physicists
University of Tokyo alumni
Hiroshima University alumni
Academic staff of Nihon University
University of Minnesota faculty
Fellows of the American Physical Society
People from Hiroshima | Hiroshi Suura | [
"Physics"
] | 242 | [
"Particle physicists",
"Particle physics"
] |
71,354,480 | https://en.wikipedia.org/wiki/CP-GEP | CP-GEP is a non-invasive prediction model for cutaneous melanoma patients that combines clinicopathologic (CP) variables with gene expression profiling (GEP). CP-GEP is able to identify cutaneous melanoma patients at low-risk for nodal metastasis who may forgo the sentinel lymph node biopsy (SLNB) procedure. The CP-GEP model was developed by the Mayo Clinic and SkylineDx BV, and it has been clinically validated in multiple studies.
Clinical relevance
The sentinel lymph node biopsy (SLNB) is the standard of care for detecting nodal metastases in cutaneous melanoma patients and has been the most informative prognostic factor to guide subsequent treatment. However, ~85% of patients undergoing this procedure have no evidence of nodal metastasis. These patients are exposed to the risk of surgical complications. Well-known complications of SLNB include seroma formation, infections, lymphedema and other comorbidities. Because the SLNb procedure is highly complex, involves multiple medical disciplines, and is difficult to standardize, the false-negative rate is relatively high at 15%. Likewise, SLNB results that show minimal tumor cell deposits are difficult to interpret and may falsely indicate high-risk disease. The use of CP-GEP is expected to reduce the number of negative, nontherapeutic SLNB, as it has been specifically developed to identify and deselect patients with a low risk of nodal metastasis (below 10%). Per current clinical guidelines (NCCN, 2022), patients with a risk of having nodal metastases below 10% may choose to forgo SLNB, whereas patients with a nodal metastases risk of greater than 10% are recommended to undergo SLNB surgery. A diagnostic tool (rule-out test) that deselects patients for SLNB is therefore likely to improve clinical care. Better patient selection for SLNB would increase the accuracy of the clinicopathological assessment and reduce the exposure to unnecessary SLNB surgeries, thereby optimizing the allocation of healthcare resources. Moreover, initial studies have shown that the CP-GEP model may help predict the likelihood of melanoma recurrence.
Model development
The CP-GEP model classifies patients as low or high risk for nodal metastasis based on patient age at melanoma biopsy (clinical factor), Breslow thickness (pathological factor) - a well-established risk factor currently used in clinical practice for melanoma staging – and the expression of eight genes from the primary tumor. These eight genes are involved in biological processes like fibrinolysis, angiogenesis, and epithelial-mesenchymal transition. The specific genes included in this CP-GEP model are MLANA, PLAT, ITGB3, SERPINE2, LOXL4, IL8, TGFBR1, and GDF15.
Technical specifications
The sample type used is Formalin-Fixed Paraffin-Embedded (FFPE) tissue from the diagnostic biopsy of the primary melanoma. This material is collected via a shaved/punched biopsy or full excision. A total of 50-micron sections (e.g., five sections of 10 micron, or 10 sections of 5 micron) is required for molecular analysis and no macrodissection is needed for further processing. Gene expression data is obtained via quantitative PCR. The CP-GEP model is a logistic regression model. A repeated nested cross-validation scheme (double loop cross validation) was used to determine the performance of CP-GEP
Clinical practice and GEP testing
In current clinical care, most providers adhere to the NCCN guidelines when considering SLNB referral of newly diagnosed melanoma patients. Currently, these guidelines do not recommend the usage of GEP testing in routine clinical practice, and state that pathological staging procedures should not be replaced. However, they do acknowledge the important potential of GEP tools in clinical care, and emphasize that these tests should be more extensively evaluated in prospective studies with large contemporary datasets of unselected patients. Scientific consensus has been reached by Grossman and colleagues from the Melanoma Working Prevention Group [ref] regarding the use of GEP tools in clinical practice. These guidelines are regarded as a benchmark for the development of GEP-based risk-stratification tools in the melanoma field.
References
Gene expression
Oncology
Clinical pathology | CP-GEP | [
"Chemistry",
"Biology"
] | 940 | [
"Gene expression",
"Molecular genetics",
"Cellular processes",
"Molecular biology",
"Biochemistry"
] |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.