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58,435,348 | https://en.wikipedia.org/wiki/List%20of%20international%20fellows%20of%20the%20Royal%20Academy%20of%20Engineering | The Royal Academy of Engineering is the UK national academy in the field of engineering. Its purpose is to bring together the most successful and talented engineers to advance and promote excellence in engineering.
Each year about 50 new fellows are admitted to the academy, after evaluation by the membership committee and election by existing fellows. Engineers who have achieved international distinction in their field, and who are not British citizens or residents, are elected and named as International Fellow and are entitled to use FREng after their names.
International fellows
Recently elected international fellows are shown below.
References
Royal Academy of Engineering
Royal Academy of Engineering
. | List of international fellows of the Royal Academy of Engineering | [
"Technology"
] | 119 | [
"Lists of engineers",
"Lists of people in STEM fields"
] |
72,310,868 | https://en.wikipedia.org/wiki/Acetaminophen%20Autism%20Mass%20Tort | On October 5, 2022, the U.S. Judicial Panel on Multidistrict Litigation (JPML) transferred some 66 autism and ADHD lawsuits to Senior District Judge Denise Cote in the Southern District of New York, thus consolidating all such acetominophen birth defect cases in a mass tort. The case specifically concerns the lack of warning regarding in utero use. On November 19 Judge Cote, among other matters, ruled against Walmart's preemption argument (which is often raised in pharmaceutical mass tort cases). Judge Cote likewise ruled against Johnson & Johnson in April 2023. Given the significant media attention and advertising the class action has been receiving, the number of plaintiffs is widely anticipated to considerably increase.
The case was thrown out December 18, 2023, with Judge Cote writing "“The unstructured approach adopted by the plaintiffs’ experts permitted cherry-picking, allowed a results-driven analysis, and obscured the complexities, inconsistencies, and weaknesses in the underlying data..."
References
United States District Court for the Southern District of New York cases
United States tort case law
21st-century controversies in the United States
Autism in the United States
Attention deficit hyperactivity disorder
Medical case law
Congenital malformation due to exogenous toxicity
Multidistrict litigation | Acetaminophen Autism Mass Tort | [
"Environmental_science"
] | 271 | [
"Toxicology",
"Congenital malformation due to exogenous toxicity"
] |
72,311,526 | https://en.wikipedia.org/wiki/Leucocoprinus%20acer | Leucocoprinus acer is a species of mushroom producing fungus in the family Agaricaceae.
Taxonomy
It was first described in 1988 by the mycologist Jörg Raithelhuber who classified it as Leucocoprinus acer.
Description
Leucocoprinus acer is a small white dapperling mushroom. Raithelhuber only described the species from a dried specimen and an illustration deposited at the herbarium of the University of Buenos Aires a decade earlier so the description may be incomplete.
Cap: 1.5-2.5 cm wide when mature, it starts hemispherical before expanding to convex. The surface is very pale, whitish with a shiny (micante), powdery (pruinose) coating whilst the centre disc has a pale red ochre colour (described as 'sinopicus' in the Latin description which refers to the pigment from Sinop, Turkey) or light chestnut brown in the German description. Stem: 3.5-4.5cm long and 2-4mm thick with a base that is not bulbous or only slightly bulbous, cylindrical. The Latin diagnosis describes the surface as pale (presumably whitish though not explicitly specified) with a red ochre colour at the base whilst the German only says that the stem is light chestnut brown. A stem ring is present and 'distinct' but no further details are supplied. Gills: White, moderately crowded (subconfertae) with the attachment described as sinuate to subfree. This would be unusual for a Leucocoprinus species as they are typically free with a collar. Spores: Subglobose or ovoid, smooth with an indistinct germ pore that is not detectable in some spores. Weakly dextrinoid. 8.8-10 x 6.5-7.2 μm. Cystidia: Claviform or truncated. Taste: bitter.
Since many Leucocoprinus species can exhibit a change of colour when dry and as no fresh material was examined to describe this species it is possible that this species may present with different colouration when fresh.
Etymology
The specific epithet acer is Latin for bitter and the species is presumably named for the taste noted in the description, however a bitter taste is not unique to this Leucocoprinus species.
Habitat and distribution
The specimens studied by Raithelhuber were found in Temperley, a district in Greater Buenos Aires, Argentina in 1972. They were observed to be growing in large groups in the morning.
References
acer
Fungi described in 1988
Fungi of South America
Fungus species | Leucocoprinus acer | [
"Biology"
] | 536 | [
"Fungi",
"Fungus species"
] |
72,311,960 | https://en.wikipedia.org/wiki/Kleptotype | In taxonomy, a kleptotype is an unofficial term referring to a stolen, unrightfully displaced type specimen or part of a type specimen.
Etymology
The term is composed of klepto-, from the Ancient Greek (kléptō) meaning "to steal", and -type referring to type specimens. It translates to "stolen type".
History
During the Second World War biological collections, like the herbarium in Berlin have been destroyed. This led to the loss of type specimens. In some cases only kleptotypes have survived the destruction, as the type material had been removed from their original collections. For instance, the type of Taxus celebica was thought to be destroyed during the Second World War, but a kleptotype has survived the war in Stockholm.
Kleptotypes have been taken by researchers, who subsequently added their unauthorised type duplicates to their own collections.
Consequences
Taking kleptotypes has been criticised as destructive, wasteful, and unethical. The displacement of type material complicates the work of taxonomists, as species identities may become ambiguous due to the lacking type material. It can cause problems, as researchers have to search in multiple collections to get a complete perspective on the displaced material. To combat this issue it has been proposed to weigh specimens before loaning types, and to identify loss of material through comparing the types weight upon return. Also, in some herbaria, such as the herbarium Kew, specimens are glued to the herbarium sheets to hinder the removal of plant material. However, this also makes it difficult to handle the specimens.
Rules concerning type specimens
The International Code of Nomenclature for algae, fungi, and plants (ICN) does not explicitly prohibit the removal of material from type specimens, however it strongly recommends to conserve the type specimens properly. It is paramount that types remain intact, as they are an irreplaceable resource and point of reference.
References
Biological concepts
Taxonomy (biology)
Zoological nomenclature
Botanical nomenclature | Kleptotype | [
"Biology"
] | 417 | [
"Zoological nomenclature",
"Botanical nomenclature",
"Botanical terminology",
"Biological nomenclature",
"Taxonomy (biology)",
"nan"
] |
72,312,626 | https://en.wikipedia.org/wiki/HD%20210056 | HD 210056, also known as HR 8432, is a solitary orange hued star located in the southern circumpolar constellation Octans. Eggen (1993) listed it as a member of the old disk population.
The object has an apparent magnitude of 6.13, making it barely visible to the naked eye. Based on parallax measurements from the Gaia satellite, the object is estimated to be 292 light years distant. It appears to be receding with a heliocentric radial velocity of . At its current distance, HD 210056's brightness is diminished by 0.2 magnitudes due to interstellar dust. It has an absolute magnitude of +1.41.
This is an evolved giant star with a stellar classification of K0 III. It has 1.59 times the mass of the Sun but has expanded to 7.72 times its girth. It radiates 29.7 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of . Based on asteroseismologic measurements, HD 210056 is estimated to be 2 billion years old. The star has about 90% of the Sun's metallicity — what astronomers define a star's abundance of chemical elements heavier than helium. It currently spins slowly with a projected rotational velocity lower than .
References
K-type giants
Octans
Octantis, 68
CD-76 01120
210056
109584
8432 | HD 210056 | [
"Astronomy"
] | 299 | [
"Octans",
"Constellations"
] |
72,312,657 | https://en.wikipedia.org/wiki/Leucocoprinus%20fibrillosus | Leucocoprinus fibrillosus is a species of mushroom producing fungus in the family Agaricaceae.
Taxonomy
It was first described in 1988 by the mycologist Jörg Raithelhuber who classified it as Leucocoprinus fibrillosus.
Description
Leucocoprinus fibrillosus is a small dapperling mushroom. Raithelhuber described the species from a dried specimen deposited in the Herbarium Anchieta - Fungi Rickiani in Brasil. The specimen had been deposited in 1943 by Johannes Rick who had identified it as Lepiota erythrella and provided an accompanying description of the fresh mushroom. Raithelhuber also examined two similar specimens from the herbarium at the University of Buenos Aires which he identified as Leucoagaricus erythrellus and Lepiota lanoso-farinosa.
Cap: 5-10cm wide, starting campanulate (bell shaped) before becoming hemispherical with a slight umbo and moderately thick flesh. The surface is smooth and pinkish-orange with radial fissures or wrinkles (rimose) and scales (subsquamous). Stem: 5-10cm long with a thickened base. The surface is white and it is cylindrical and hollow. The stem ring is movable or nearly movable. Gills: White. No other description is provided besides that the gill edges are entire (integrae). Spores: Ovoid to elliptical or subamygdaliform, thin walled and smooth without a germ pore. 7.3-8.4 x 3.5-4.5 μm. The spores are hyaline but the colour in Melzer's reagent is not made clear in the description with Raithelhuber describing them as 'not or slightly amyloid or pseudoamyloid' in the Latin diagnosis and 'at most weakly dextrinoid' in German.
The colouration of this mushroom is described as very variable presenting with reddening, bluing or green discolouration. However it is not noted specifically where this discolouration takes place so it may apply to the whole mushroom. Raithelhuber classified this mushroom as a Leucocoprinus species based on the campanulate, wrinkled cap and the discolouration but noted that the spores of Leucocoprinus species typically have a germ pore whilst this specimen was missing one. However Leucocoprinus are typically striated rather than wrinkled as described and this discolouration does not sound typical for them so the placement of this specimen in Leucocoprinus seems strange and it may simply not have been reclassified yet.
Etymology
The specific epithet fibrillosus is Latin for fibrous. Raithelhuber stated that the description largely agreed with Carlo Luigi Spegazzini's 1899 description of Lepiota erythrella var. fibrillosa so that name was retained.
Habitat and distribution
The specimens studied by Raithelhuber were found in the woods near São Salvador, Brazil in 1943.
References
fibrillosus
Fungi described in 1988
Fungi of South America
Fungus species | Leucocoprinus fibrillosus | [
"Biology"
] | 654 | [
"Fungi",
"Fungus species"
] |
72,312,718 | https://en.wikipedia.org/wiki/Martin%20Albrecht%20%28chemist%29 | Martin Albrecht (born December 12, 1971) is a Swiss chemist. He is Professor of Inorganic Chemistry at the Department of Chemistry, Biochemistry and Pharmacy at the University of Bern. He is known for his contribution to carbene chemistry, particularly with his work on 1,2,3-triazolylidene mesoionic carbene.
Education
Martin Albrecht completed his undergraduate education at the University of Bern from 1991 to 1996. His early research career started in 1996 during his PhD studies under the supervision of Prof. Dr. Gerard van Koten at Utrecht University, in The Netherlands. He studied the formation and properties of novel inorganic materials using the privileged pincer ligand platform which led, for example, to discoveries such as organoplatinium complexes that appeared applicable as very sensitive SO2 sensors. In 2001, Martin Albrecht was awarded the Backer price from the Royal Dutch Chemical Society (KNCV) in recognition of his PhD thesis work.
Career and Research
After his PhD, he joined, in 2001 Prof. Dr. Robert H. Crabtree's research team at Yale, USA, to develop the coordination chemistry of N-Heterocyclic carbene (NHC) ligands with various metals and to study their application as catalysts in C–H activation reactions.
This period was followed by a short stay, 2002–2003, as researcher R&D Coating Effects, in Ciba Specialty Chemicals (Basel, CH). Then, Martin Albrecht accepted a position as Alfred Werner assistant professorship in Fribourg, Switzerland working on NHC coordination chemistry, on the edge with biology. For this research, he was granted a European Research Council starting grant in 2005 for the CARBENZYMES project that aimed to understand the bonding properties of metalloenzymes.
In 2009, he joined the University College Dublin as a full Professor. He developed a productive research program using novel 1,2,3-triazolylidene mesoionic carbene ligands.
At that time, he received a European Research Council Consolidator Grant in 2014 for the synMICs project that aimed at the exploration of sustainable pathways for the efficient production of pharmaceutical drugs and for energy storage with 3d metals.
In 2015, he moved with his research group back to Bern, Switzerland to continue his research on donor flexible ligands as Professor of Inorganic Chemistry. Since 2021, he has been deputy director of the Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern. In 2021, the 1st year Biology Bachelor students recognized his commitment to teach young undergraduate students, to inspire them and to act as a scientific role model by nominating him for the "Teacher of the year 2021" award.
Major grants and Awards
2016 GIAN fellow (Indian Ministry of Human Resource Development)
2015 Catalysis Society of South Africa (CATSA eminent visitor)
2014 European Research Council Consolidator Grant
2013 Bessel Award (Humboldt Foundation)
2011 Fellow of the Royal Society of Chemistry (RSC)
2008 Visiting Professor (University of Otago, New Zealand)
2007 European Research Council Starting Grant
2002 Alfred Werner Assistant Professorship (Alfred Werner Foundation)
2001 Bakker price from the Royal Dutch Chemical Society (KNCV)
References
Swiss chemists
1971 births
Living people
University of Bern alumni
Inorganic chemists
Utrecht University alumni | Martin Albrecht (chemist) | [
"Chemistry"
] | 668 | [
"Inorganic chemists"
] |
72,313,293 | https://en.wikipedia.org/wiki/Data%20care | Data care refers to treating people and their private information fairly and with dignity. Data has progressively become more and more utilized in our society all over the world. When it comes to securely storing a medical patient's data, an employee's data, or a citizen's private data. The concept of data care emerged from the increase of data usage over the years, it is a term used to describe the act of treating people and their data with care and respect. This concept elaborates on how caring for people's data is the responsibility of those who govern data, for example, businesses and policy makers. Along with how to care for it in an ethical manner, while keeping in mind the people that the data belongs to. And discussing the concept of 'slow computing' on how this can be properly utilized to help in creating and maintaining proper data care.
Defining data care
To define data care means treating people and their private information fairly and with dignity in terms of their data. Data care is a term used by the cybersecurity industry, to teach people to be more careful with their data on social media and their mobile devices. Such information could be their banking information, address, and other personal information. In 2019, a United States bill required social media platforms to be more responsible with their users' private data, which will help in ensuring proper data care. This is one example in how implementing proper data care policy will help put pressure on these companies to achieve data justice. Data care aims to allow data navigation while countering data power, and encourages "slow computing" (see below), all of which will help in reducing datafication, and making it more difficult for people's data to become traceable. This will also encourage open source alternatives for data to become more difficult to trace. This is something the cybersecurity industry has been working toward for some time, as a means to help protect people's privacy. Proper data care will help those with weaker data literacy, it will help manage data in political campaigns, and help place pressure on companies to be more ethical in their data use. This can help in producing open source apps, and creating technology that prioritizes the public's private information. Proper data care will help achieve data justice, and lead to data sovereignty.
Ethics of care
Prioritizing proper care and respect towards people's data is of utmost importance, requiring good morals and proper ethical choices to protect people's privacy. Data care involves protecting people's data in medical practices, law, politics, the organization of society, war, and international relations. Hospitals keep their patient's data secure, data such as; routine healthcare data and patient contact. Data is now being kept electronically, replacing paper files. Data obtained from hospitals will often be subject to research, the results cannot be traced to individual participants, and the patients are informed beforehand in case they want to opt out of having their data used in research. Data care is seen as a form of ethics, considering moralities of justice and rights.
Understanding data
The global rise in digital data has led to billions of consumers worldwide, this could allow corporations to utilize this data in an unethical way. Data can be used by authority figures to access, use, or manage people's data, data could also be used to discriminate against low income individuals. Digital data is also being used to track and monitor people. With the rise of smart cities, the increase in digital and biometric registration are becoming the norm around the world. The concept of "data justice" brings awareness to this phenomenon, and encourages data to be used morally and ethically by establishing rules of law. Methods that can be used to enhance data care are to utilize tools such as ad blockers, cookie blockers, proper malware detection and interception, site blocking, encryption tools, and services to opt out of databases controlled by data brokers.
Slow computing
Data care calls for "slow computing," which is an ethical way to morally utilize people's data that intends to protect their privacy in regards to data-driven systems. In other words, slow computing prioritizes protecting people's private information on digital and mobile devices, so they may use these devices without feeling harassed, stressed, or exploited in any way. Then people will be able to enjoy using these devices in conjunction with the slow living movement of enjoyment, patience, sovereignty, authenticity, responsibility, and sustainability. Enforcing the idea of slow computing would involve encouraging corporations to employ market-led regulations on data, and promoting practices such as privacy-by-design. Also encouraging political parties to implement slow computing ideologies into their systems as policy proposals. Governments could also implement their own forms of slow computing for better data care, encouraging fair information principles, privacy-by-design, enacting new legislation that protects people's rights, while also employing other methods of slow computing in their programs and practices. Avoiding data extraction will also help improve data care; industry-led moves, government and policy makers employing new regulations, and data sovereignty agreed upon by communities. A digital society and economy that focuses on a slow computing world would focus on fairness, equity, and justice.
See also
Applied ethics
Computers, Freedom and Privacy Conference
Electronic Frontier Foundation
References
Information privacy
Computer ethics | Data care | [
"Technology",
"Engineering"
] | 1,072 | [
"Cybersecurity engineering",
"Information privacy",
"Computing and society",
"Ethics of science and technology",
"Computer ethics"
] |
72,314,003 | https://en.wikipedia.org/wiki/Magnetic%20chicane | A magnetic chicane also called a bunch compressor helps form dense bunches of electrons in a free-electron laser. A magnetic chicane makes electrons detour slightly from their otherwise straight path, and in that way is similar to a chicane on a road.
A magnetic chicane consists of four dipole magnets, giving electrons at the beginning of a bunch a longer path than electrons at the end of the bunch, thereby allowing the lagging electrons to catch up.
Free-electron laser
A free-electron laser depends upon a beam of tightly bunched electrons. Short bunches of electrons are produced by a photoinjector, but they quickly elongate, because electrons have negative charge and little mass, causing the bunch to expand. As the bunch is accelerated, the electrons gain mass and quickly approach the speed of light. After that, electrons at the end of the bunch cannot go any faster to catch up with electrons at the beginning of the bunch.
Chirp
This problem is solved by adjusting the phase of the driving electric field to more strongly add energy and mass to electrons at the trailing end of the bunch. This is called negative energy chirp, meaning the energy decreases along the direction of beam travel. Because the beam is traveling at almost the speed of light, the trailing electrons gain mass, rather than velocity. This results in a correlation between mass and position in the bunch.
Chicane
The chicane gives lagging electrons time to catch up. More massive electrons are deflected less by the magnetic field than lighter electrons, and therefor take a shorter path through the chicane, resulting in a shorter bunch. A chicane consists of four dipole magnets with the following roles:
Deflects the beam slightly away from the central axis of the accelerator, with lighter electrons deflected more than more massive electrons.
Deflects the beam in the opposite direction, making it parallel to the central axis, but with an offset. The offset is greatest for lighter electrons.
Deflects the beam back towards the central axis.
Deflects the beam back in the direction of the central axis.
Limitations
In practice, bunch compression cannot be done a single step. To avoid beam emittance blowup, beam compression is usually done by using two chicanes.
References
External links
RF and Space Charge Emittance in Guns, a basic definition of emittance
Space Charge Induced Beam Emittance Growth and Halo Formation
Electron beam
Free-electron lasers
Accelerator physics | Magnetic chicane | [
"Physics",
"Chemistry"
] | 508 | [
"Electron",
"Applied and interdisciplinary physics",
"Electron beam",
"Experimental physics",
"Particle physics",
"Particle physics stubs",
"Accelerator physics"
] |
72,314,236 | https://en.wikipedia.org/wiki/HD%20191220 | HD 191220, also known as HR 7698, is a solitary white hued star located in the southern circumpolar constellation Octans. It has an apparent magnitude of 6.14, placing it near the limit for naked eye visibility. The object is located relatively close at a distance of 245 light years based on Gaia DR3 parallax measurements but is slowly receding with a heliocentric radial velocity of . At its current distance, HD 191220's brightness is diminished by 0.22 magnitudes due to interstellar dust.
This is a chemically peculiar Am star with a stellar classification of A2/3mA8-F0, an A-type star with the metallic lines of a star with a class of A8-F0. It has double the mass of the Sun and 2.2 times its girth. It radiates 15.57 times the luminosity of the Sun from its photosphere at an effective temperature of . HD 191220 is estimated to be nearly a billion years old and has a near solar metallicity — what astronomers dub a star's abundance of chemical elements heavier than helium.
References
A-type main-sequence stars
Am stars
Octans
191220
100697
7698
CD-83 00253
Octantis, 45 | HD 191220 | [
"Astronomy"
] | 269 | [
"Octans",
"Constellations"
] |
72,315,475 | https://en.wikipedia.org/wiki/Karmitoxin | Karmitoxin is an amine-containing polyhydroxy-polyene toxin isolated from Karlodinium armiger strain K-0668. It is structurally related to amphidinols, luteophanols, lingshuiols, carteraols, and karlotoxins.
See also
Prymnesin-1
Prymnesin-2
References
Amines
Heterocyclic compounds with 1 ring
Oxygen heterocycles
Phycotoxins
Polyether toxins
Primary alcohols
Secondary alcohols | Karmitoxin | [
"Chemistry"
] | 112 | [
"Toxins by chemical classification",
"Polyether toxins",
"Functional groups",
"Amines",
"Bases (chemistry)"
] |
72,316,222 | https://en.wikipedia.org/wiki/OneLove | OneLove is an anti-discrimination, anti-racism, LGBT+ rights and human rights campaign, started during the 2020 football season by the Dutch Football Association, that invites football players to wear armbands with the rainbow-coloured OneLove logo. Attracting controversy when worn in nations that have homophobic or anti-LGBT+ laws, it became prominent during the men's 2022 FIFA World Cup.
History
The OneLove campaign kicked off in the Netherlands at the start of the 2020 football season, largely in response to racism in Dutch football, with an open letter rejecting any form of discrimination. The letter emphasised that, internationally, football unites millions of people from all parts of society. That message was shown on billboards in football stadiums where the Netherlands national team played their games. The OneLove logo was also worn on team jerseys during the KNVB Cup Final between Ajax and PSV. The campaign then spread its advertising to print and video media. Netherlands captain Georginio Wijnaldum wore the OneLove armband during UEFA Men's Euro 2020. In June 2021, another open letter was published, this time saying that the fans were proud of their teams for the OneLove campaign.
At the UEFA Women's Euro 2022, most captains wore either a OneLove or Stonewall rainbow armband, including winning England captain Leah Williamson, Sweden captain Kosovare Asllani, and Norway captain Ada Hegerberg, who was also wearing it to honour the victims of the 2022 Oslo shooting.
The OneLove campaign's impact in the Netherlands saw it spread to other European countries, with ten national men's teams (Belgium, Denmark, England, France, Germany, the Netherlands, Norway, Sweden, Switzerland and Wales) agreeing to wear the armband for all their UEFA Nations League and FIFA World Cup matches, beginning in September 2022. Two of those nations did not qualify for the 2022 FIFA World Cup, and England did not wear the armband while in official mourning of Elizabeth II.
In December 2022, during the 2022 World Cup, Dutch music artists Yellow Pearl and Noah Jaora collaborated on a single titled "OneLove", having consulted with the Dutch Football Association. The single was released to support the campaign.
The England women's team continued to wear the OneLove armband in 2023, also in recognition of Czech men's player Jakub Jankto coming out while an active international, with Williamson saying that she wished to continue wearing it at the 2023 FIFA Women's World Cup and that if there was a decision about it, "you hope it's not a last-minute call once [teams] get there". Shortly afterwards, FIFA president Gianni Infantino announced that they "are looking for a dialogue and we will have a solution in place well before the Women's World Cup." In the weeks before the tournament, FIFA upheld its ban of the OneLove armband, though it revealed its own similar design, with the same colours in a heart, as an option.
In March 2023, Dutch player Redouan El Yaakoubi chose to step away from captaining Excelsior Rotterdam so that he did not have to publicly support the campaign.
Armband design
The armband features a heart with multicoloured stripes and a numeral "1". The words "#ONE" and "LOVE" are on either side of the heart. The colours in the logo are not those of the rainbow or LGBT pride flag; instead, they symbolise "race and heritage (red/black/green) and all gender identities and sexual orientations (pink/yellow/blue)". The choices for the colour combinations were inspired by the Pan-African flag and the pansexual flag respectively.
Controversies
UEFA Men's Euro 2020
Rejection of the armband was first seen in 2021, when Wijnaldum wore it in a Men's Euro 2020 match against the Czech Republic that was held in Budapest, Hungary. The Hungarian government had shortly before passed a law that banned mentions of homosexuality and transgender issues in education. Dutch fans had also been stopped from taking rainbow flags into the stadium fan zone; UEFA said that any restrictions were made by local security and that it welcomed rainbow Pride symbols, adding that it had informed the Hungarian Football Federation that "rainbow-colored symbols are not political and in line with UEFA's #EqualGame campaign, which fights against all discrimination, including against the LGBTQI+ community, such flags will be allowed into the stadium."
2022 Men's FIFA World Cup
European players who had previously worn rainbow armbands informed FIFA of their intention to continue with the gesture at the 2022 Men's FIFA World Cup, held in Qatar. Their plan to do so gained widespread attention in the days before the start of the tournament, due to increasing criticisms of Qatar's attitude towards homosexuality.
After having arrived at the tournament, the relevant associations were warned that players would be at minimum booked for wearing rainbow armbands, rather than just receive the expected fine; a joint statement by England, Wales, Belgium, Denmark, Germany, Switzerland and the Netherlands confirmed they would not wear the armband as doing so would affect players. The decision from FIFA coming so late, as well as FIFA "silencing anti-discrimination work within the game", was criticised.
Instead of the captains, several people associated with national teams wore the armband. Most prominent was queer BBC pundit and former England women's captain Alex Scott, who wore the armband while reporting on the England vs Iran match on 21 November. German interior minister Nancy Faeser attended Germany's first game at the World Cup on 23 November, where she wore the armband. UK sports minister Stuart Andrew, who is gay, wore it while attending the match between England and Wales.
The German Men's team were particularly critical of FIFA's decision to ban the armband. At their first game, the team covered their mouths in protest of being silenced. When the lack of armband caused one of their sponsors to drop out, the German football association replaced the sponsor's logo with the OneLove symbol in their press centre at the World Cup.
Similar actions
In October 2017, Georgian footballer Guram Kashia wore a rainbow-striped captain's armband for Dutch club (against Heracles Almelo) in support of LGBT rights, leading to backlash in his country and calls for him to step down from the Georgian Men's national team.
The popularity of the OneLove armband in European football, and though it is not only in support of LGBT+ rights, prompted some captains to also wear a fully rainbow design armband produced by British LGBT+ advocacy group Stonewall, which had promoted its rainbow laces campaign for LGBT+ visibility in sport since 2013.
Germany Men's captain Manuel Neuer wore a rainbow armband inspired by the campaign throughout the Men's Euro 2020 and at a pre-tournament friendly. UEFA initially opened an investigation of Neuer and the German Football Association, suggesting his armband was a breach of political neutrality; the investigation closed with the determination that "the armband has been assessed as a team symbol for diversity and thus for a 'good cause.'" In the Men's Germany match against England at Wembley, after the investigation was dropped, Neuer continued to wear his rainbow armband and the three Lions' captain Harry Kane wore the OneLove armband. The match fell during June, a Pride Month; Kane had worn rainbow armbands on other occasions to no controversy, particularly in the Premier League for Tottenham, during Pride events.
See also
Show Racism the Red Card
References
21st-century social movements
2020s controversies
Anti-racism
Discrimination
Hashtags
Heart symbols
Human rights
LGBTQ political advocacy groups in the United Kingdom
LGBTQ-related controversies in sports
LGBTQ-related controversies in the United Kingdom
LGBTQ rights
Love
Mass media and entertainment controversies
FIFA Women's World Cup controversies
Slogans
2022 FIFA World Cup controversies | OneLove | [
"Mathematics",
"Biology"
] | 1,648 | [
"Behavior",
"Symbols",
"Heart symbols",
"Aggression",
"Discrimination"
] |
72,318,877 | https://en.wikipedia.org/wiki/Ilsemannite | Ilsemannite is an uncommon amorphous complex heterovalent molybdenum oxide, that was first published in 1871, and has been a valid species since pre-IMA. It is a grandfathered mineral, meaning the name ilsemannite is still believed to refer to a valid species. However, it is likely that specimens formed under different conditions, in different localities do not have the same composition, and may even be a mixture of compounds. Furthermore, it is hard to analyze the specimens due to them being a mixture, hence why adequate analyses are lacking of said mineral. Ilsemannite is believed to be identical to synthetic molybdic oxide.
Properties
Ilsemannite is soluble in water, which at first produces a greenish blue color, which later changes to a deep molybdenum-blue. This is probably why Native Americans believed that ilsemannite colored the waters blue in the Idaho Springs area, however, this has been debunked. Ilsemannite is now believed to consist of molybdenum (66.34%) and oxygen (33.19%), having a negligible amount of hydrogen (0.46%) in it. It has an earthy, dull, clay-like texture, and it is amorphous, meaning ilsemannite does not grow crystals. It does not show any radioactive properties.
In an occurrence near Ouray, Utah, researchers found ilsemannite specimens disseminated through a rock. Analyses showed that about 10% of the sample was water-soluble, and that the water-soluble portion contains iron sulfate. Back then, in 1917, researches concluded that specimens from other localities all showed that iron sulfate was present in each of them, which is why the formula of said mineral was believed to be MoO3·SO3·5H2O. A specimen from Saxony mixed with iron sulfate showed only small amounts of iron, and gave a strong sulfate reaction. Another specimen from Carinthia had the same reaction, however this specimen had only a trace of ferric iron, with no ferrous iron in it. The specimen from Cripple Creek, Colorado showed the exact same reaction.
During a study, it was found out that jordisite alters to ilsemannite more readily than it does to molybdenite, probably due to its amorphous state. This, among the scarcity of jordisite in mineral deposits, could explain why ilsemannite can be discovered in molybdenum districts. When first found, the mineral is usually black-blue or black in color, and it turns to blue-green and fades when exposed to sunlight. When put in a furnace alongside cinnabar, the calcined product's color changed to a purplish pink color. Chemical analyses of the material were not obtained due to the fact that the very thin coating surrounding ilsemannite couldn't be separated from the specimens. Underneath this coating there was a black, submetallic, sectile mineral first believed to be metacinnabar, but it was later proved to be a molybdenum compound. It was obvious that ilsemannite was an alteration product of this compound. The specimen from Colorado was described to have this coating as well, only that this time it was green. It is believed that the specimen was actually either a yellow iron sulfate, or a yellow molybdite, which was colored green due to the ilsemannite solution.
Occurrences and localities
Ilsemannite forms by the oxidation of molybdenum-bearing minerals, making it a secondary mineral. It is associated with gypsum, wulfenite, melanterite, halotrichite, molybdite, molybdenite, jordisite, and other oxidized uranium minerals; however, it had been found in association with cinnabar as well in 1939. In the aforementioned encounter, ilsemannite was found as veinlets and as irregular lenses or pods in association of the cinnabar specimens. These specimens were described to often stain the nearby calcites a light blue color. It has a type locality of Carinthia, and although it is an uncommon mineral, it has been described in more than a dozen of other localities since then. Despite this fact, there is still an uncertainty lingering around the chemical composition and the origin of the mineral.
References
Mineral County, Colorado
Amorphous solids
Molybdenum minerals | Ilsemannite | [
"Physics"
] | 938 | [
"Amorphous solids",
"Unsolved problems in physics"
] |
72,319,626 | https://en.wikipedia.org/wiki/Intuitive%20eating | Intuitive eating is an approach to eating that focuses on the body's response to cues of hunger and satisfaction. It aims to foster a positive relationship with food as opposed to pursuing "weight control". Additionally, intuitive eating aims to change users' views about dieting, health, and wellness, instilling a more holistic approach. It also helps to create a positive attitude and relationship towards food, physical activity, and the body.
The term "intuitive eating", coined by registered dietitians Evelyn Tribole and Elyse Resch, first appeared in a 1990s peer-reviewed journal article. In 2012, Tribole's and Resch's book Intuitive Eating: A Revolutionary Program that Works was published, identifying ten components of intuitive eating and reviewing the scientific research that has been conducted on it.
Characteristics
Unlike most diets, intuitive eating does not try to ban or restrict certain foods, with its mindset being that food should not be looked at as "good or bad". Practitioners are instead encouraged to listen to their body and eat what feels right for them.
Intuitive eating follows 10 guidelines:
Reject the diet mentality
Honor your hunger
Make peace with food
Challenge the food police
Feel your fullness
Discover the satisfaction factor
Cope with your emotions without using food
Respect your body
Exercise
Honor your health
Research
Weight loss and chronic disease control
Intuitive eating has been shown to be as effective as diet intervention for short-term weight loss, and to decrease weight significantly more than in control groups that had no diet intervention. Long-term weight loss from intuitive eating might be possible, but this possibility is not yet well-studied.
Intuitive eating may lead to less frequent overeating and better self-regulation in terms of calorie consumption.
Intuitive eating may be equally effective as a diabetes self-management education (DSME) and a lifestyle weight loss program, although further research is needed.
In overweight or obese pregnant women, intuitive eating can also help lower glucose levels.
Intuitive eating may help to lower cholesterol and fasting glucose levels, improve HbA1C levels, and lower systolic and diastolic blood pressure.
A study from 2022 showed that lifestyle interventions focused on weight loss that also included intuitive eating had better weight loss maintenance results than those without intuitive eating.
Disordered eating and body acceptance
Intuitive eating may help to decrease eating disorder symptoms and behaviors as well as decrease weight stigma and concerns about weight.
A 2022 review found that intuitive eating helped to decrease dieting.
A 2016 review found that it correlated with self-esteem and self-compassion. Another review found that it could lead to improved quality of life, body image, and body appreciation.
A 2019 study revealed that women who followed intuitive eating patterns were able to let go of the concepts of "good" and "bad" foods that are commonly promoted by diet culture, allowing them to eat a more balanced, sustainable, and non-restrictive diet.
Drawbacks and limitations
Intuitive eating has shown growth as a possible method for losing weight and yielding health benefits. However, researchers warn that there is not enough research to support that it can assist with weight loss long-term, or with maintaining weight loss. Furthermore, doctors and registered dietitians warn that this "non-diet" diet approach will yield different results for different people.
People with certain health conditions may be instructed by their doctor to follow a particular diet, eliminating the choice to follow an intuitive eating diet. Critics have also argued that because intuitive eating is so broad, with no given diet plan or food restrictions, it can be hard for some users to know what to eat and how much to eat. It can be a steep learning curve to accurately respond to one's hunger and fullness cues.
See also
Health at Every Size
Human nutrition
Body positivity
References
Diets
Eating behaviors of humans
Health movements
Pseudoscience | Intuitive eating | [
"Biology"
] | 780 | [
"Eating behaviors",
"Behavior",
"Human behavior",
"Eating behaviors of humans"
] |
72,320,235 | https://en.wikipedia.org/wiki/PW%20Telescopii | PW Telescopii, also known as HD 183806 or simply PW Tel, is a solitary variable star located in the southern constellation Telescopium. It has an average apparent magnitude of 5.58, making it faintly visible to the naked eye. Based on parallax measurements from the Gaia satellite, the star is estimated to be 395 light years distant. It appears to be approaching the Solar System with a heliocentric radial velocity of . The value is somewhat constrained, having an uncertainty of 26%. At its current distance, PW Tel's brightness is diminished by 0.05 magnitudes due to interstellar dust.
PW Tel was first noticed to vary in brightness in observations taken in 1978 by Pierre Renson. The star was confirmed to be variable and was given the variable star designation PW Telescopii in 1981. Further observations by Jean Manfroid in 1985 improved earlier data, including the star's period. PW Tel is an α2 CVn variable that has an amplitude of 0.011 magnitudes within the visual passband and a period of 2.92 days.
With a stellar classification of A0 Vp (SrCr), PW Tel is a chemically peculiar A-type main-sequence star. It has been recognised as an Ap star, as indicated by the "p" suffix, since the early 20th century, and it shows an overabundance of strontium and chromium in its spectrum. The abundance of some metals in the spectrum is several hundred times higher than in the Sun and it has an overall metallicity of [Fe/H] = 1.09, but this only reflects levels of those elements in the photosphere, not the whole star. Like most such stars it spins relatively slowly, with a projected rotational velocity of .
With 2.8 times the mass of the Sun and 3.4 times its radius, PV Tel radiates 100 times the luminosity of the Sun from its photosphere at an effective temperature of , giving it a bluish-white hue. PW Tel is metal enriched, having an iron abundance over 10 times that of the Sun.
References
Ap stars
A-type main-sequence stars
Telescopium
Telescopii, 63
Telescopii, PW
CD-13296
183806
96178
7416 | PW Telescopii | [
"Astronomy"
] | 493 | [
"Telescopium",
"Constellations"
] |
72,320,451 | https://en.wikipedia.org/wiki/Harmonic%20tensors | In this article spherical functions are replaced by polynomials that have been well known in electrostatics since the time of Maxwell and associated with multipole moments. In physics, dipole and quadrupole moments typically appear because fundamental concepts of physics are associated precisely with them.
Dipole and quadrupole moments are:
,
,
where is density of charges (or other quantity).
Octupole moment
is used rather seldom. As a rule, high-rank moments are calculated with the help of spherical functions.
Spherical functions are convenient in scattering problems. Polynomials are preferable in calculations with differential operators. Here, properties of tensors, including high-rank moments as well, are considered to repeat basically features of solid spherical functions but having their own specifics.
Using of invariant polynomial tensors in Cartesian coordinates, as shown in a number of recent studies, is preferable and simplifies the fundamental scheme of calculations
.
The spherical coordinates are not involved here. The rules for using harmonic symmetric tensors are demonstrated that directly follow from their properties. These rules are
naturally reflected in the theory of special functions, but are not always obvious, even though the group properties are general
.
At any rate, let us recall the main property of harmonic tensors: the trace over any pair of indices vanishes
.
Here, those properties of tensors are selected that not only make analytic calculations more compact and reduce 'the number of factorials' but also allow correctly formulating some fundamental questions of the theoretical physics
.
General properties
Four properties of symmetric tensor lead to the use of it in physics.
A. Tensor is homogeneous polynomial:
,
where is the number of indices, i.e., tensor rank;
B. Tensor is symmetric with respect to indices;
C. Tensor is harmonic, i.e., it is a solution of the Laplace equation:
;
D. Trace over any two indices vanishes:
,
where symbol denotes remaining indices after equating .
Components of tensor are solid spherical functions. Tensor can be divided by factor to acquire components in the form of spherical functions.
Multipole tensors in electrostatics
The multipole potentials arise when the potential of a point charge is expanded in powers of coordinates of the radius vector ('Maxwell poles')
. For potential
,
there is well known formula:
,
where the following notation is used. For the th tensor power of the radius vector
,
and for a symmetric harmonic tensor of rank ,
.
The tensor is a homogeneous harmonic polynomial with described the general properties. Contraction over any two indices (when the two gradients become the operator) is null. If tensor is divided by , then a multipole harmonic tensor arises
,
which is also a homogeneous harmonic function with homogeneity degree .
From the formula for potential follows that
,
which allows to construct a ladder operator.
Theorem on power-law equivalent moments in electrostatics
There is an obvious property of contraction
,
that give rise to a theorem simplifying essentially the calculation of moments in theoretical physics.
Theorem
Let be a distribution of charge. When calculating a multipole potential,
power-law moments can be used instead of harmonic tensors (or instead of spherical functions ):
.
It is an advantage in comparing with using of spherical functions.
Example 1.
For the quadrupole moment, instead of the integral
,
one can use 'short' integral
.
Moments are different but potentials are equal each other.
Formula for a harmonic tensor
Formula for the tensor was considered in using a ladder operator.
It can be derived using the Laplace operator. Similar approach is known in the theory of special functions. The first term in the formula, as is easy
to see from expansion of a point charge potential, is equal to
.
The remaining terms can be obtained by repeatedly applying the Laplace operator and
multiplying by an even power of the modulus . The coefficients are easy to determine by substituting expansion in the Laplace equation . As a result, formula is following:
.
This form is useful for applying differential operators of quantum mechanics and electrostatics to it. The differentiation generates product of the Kronecker symbols.
Example 2
,
,
.
The last quality can be verified using the contraction with . It is convenient
to write the differentiation formula in terms of the symmetrization operation.
A symbol for it was proposed in, with the help of sum taken over all independent
permutations of indices:
.
As a result, the following formula is obtained:
,
where the symbol is used for a tensor power of the Kronecker symbol and conventional symbol [..] is used for the two subscripts that are being changed under symmetrization.
Following one can find the relation between the tensor and solid spherical functions. Two unit vectors are needed: vector directed along the -axis and complex vector .
Contraction with their powers gives the required relation
,
where is a Legendre polynomial .
Special contractions
In perturbation theory, it is necessary to expand the source in terms of spherical functions. If the source is a polynomial, for example, when calculating the Stark effect, then the integrals are standard, but cumbersome. When calculating with the help of invariant tensors, the expansion coefficients are simplified, and there is then no need to integrals. It suffices, as shown in, to calculate contractions that lower the rank of the tensors under consideration.
Instead of integrals, the operation of calculating the trace
of a tensor over two indices is used. The following rank reduction formula is useful:
,
where symbol [m] denotes all left (l-2) indices.
If the brackets contain several factors with the Kronecker delta, the following relation formula
holds:
.
Calculating the trace reduces the number of the Kronecker symbols by one, and the rank of the harmonic tensor on the right-hand side of the equation decreases by two. Repeating the calculation of the trace k times eliminates all the Kronecker symbols:
.
Harmonic 4D tensors
The Laplace equation in four-dimensional 4D space has its own specifics. The potential of a point charge in 4D space is equal to
. From the expansion of the point-charge potential with respect to powers the multipole 4D potential arises:
.
The harmonic tensor in the numinator has a structure similar to 3D harmonic tensor. Its contraction with respect to any two indices must vanish. The dipole and quadruple 4-D tensors, as follows from here, are expressed as
,
,
The leading term of the expansion, as can be seen, is equal to
The method described for 3D tensor, gives relations
,
.
Four-dimensional tensors are structurally simpler than 3D tensors.
Decomposition of polynomials in terms of harmonic functions
Applying the contraction rules allows decomposing the tensor with respect to the harmonic ones.
In the perturbation theory, even the third approximation often considered good. Here, the decomposition of the tensor power up to the rank l=6 is presented:
, ,
, ,
, ,
, ,
, :.
To derive the formulas, it is useful to calculate the contraction with respect two indices, i.e., the trace. The formula for then implies the formula for . Applying the trace, there is convenient to use rules of previous section. Particular, the last term of the relations for even values of has the form
.
Also useful is the frequently occurring contraction over all indices,
which arises when normalizing the states.
Decomposition of polynomials in 4D space
The decomposition of tensor powers of a vector is also compact in four dimensions:
, ,
, ,
, ,
, ,
, :.
When using the tensor notation with indices suppressed, the last equality becomes
, .
Decomposition of higher powers is not more difficult using contractions over two indices.
Ladder operator
Ladder operators are useful for representing eigen functions in a compact form.
They are a basis for constructing coherent states
. Operators considered here, in mani respects close to the 'creation' and 'annihilation' operators of an oscillator.
Efimov's operator that increases the value of rank by one was introduced in
. It can be obtained from expansion of point-charge potential:
.
Straightforward differentiation on the left-hand side of the equation yields a vector operator acting on a harmonic tensor:
,
where operator
multiplies homogeneous polynomial by degree of homogeneity .
In particular,
,
.
As a result of an - fold application to unity, the harmonic tensor arises:
,
written here in different forms.
The relation of this tensor to the angular momentum operator is as follows:
.
Some useful properties of the operator in vector form given below. Scalar product
yields a vanishing trace over any two indices. The scalar product of vectors
and is
,
,
and, hence, the contraction of the tensor with the vector can be expressed as
,
where is a number.
The commutator in the scalar product on the sphere is equal to unity:
.
To calculate the divergence of a tensor, a useful formula is
,
whence
( on the right-hand side is a number).
Four-dimensional ladder operator
The raising operator in 4D space
has largely similar properties. The main formula for it is
where is a 4D vector, ,
,
and the operator multiplies a homogeneous polynomial by its degree. Separating the variable is convenient for physical problems:
.
In particular,
,
.
The scalar product of the ladder operator and is as simple as in 3D space:
.
The scalar product of and is
.
The ladder operator is now associated with the angular momentum operator and additional operator of rotations in 4D space . They perform Lie algebra as the angular momentum and the Laplace-Runge-Lenz operators.
Operator has the simple form
.
Separately for the 3D -component and the forth coordinate
of the raising operator, formulas are
,
.
See also
Tensor
Spherical harmonics
Operator (physics)
Laplace-Runge-Lenz vector
Angular momentum operator
Ladder operator
Multipolar exchange interaction
References
External links
Harmonic analysis
Rotational symmetry
Quantum mechanics
Operator theory | Harmonic tensors | [
"Physics"
] | 2,023 | [
"Theoretical physics",
"Quantum mechanics",
"Symmetry",
"Rotational symmetry"
] |
72,323,059 | https://en.wikipedia.org/wiki/Structural%20identifiability | In the area of system identification, a dynamical system is structurally identifiable if it is possible to infer its unknown parameters by measuring its output over time. This problem arises in many branch of applied mathematics, since dynamical systems (such as the ones described by ordinary differential equations) are commonly utilized to model physical processes and these models contain unknown parameters that are typically estimated using experimental data.
However, in certain cases, the model structure may not permit a unique solution for this estimation problem, even when the data is continuous and free from noise. To avoid potential issues, it is recommended to verify the uniqueness of the solution in advance, prior to conducting any actual experiments. The lack of structural identifiability implies that there are multiple solutions for the problem of system identification, and the impossibility of distinguishing between these solutions suggests that the system has poor forecasting power as a model. On the other hand, control systems have been proposed with the goal of rendering the closed-loop system unidentifiable, decreasing its susceptibility to covert attacks targeting cyber-physical systems.
Examples
Linear time-invariant system
Consider a linear time-invariant system with the following state-space representation:
and with initial conditions given by and . The solution of the output is
which implies that the parameters and are not structurally identifiable. For instance, the parameters generates the same output as the parameters .
Non-linear system
A model of a possible glucose homeostasis mechanism is given by the differential equations
where (c, si, p, α, γ) are parameters of the system, and the states are the plasma glucose concentration G, the plasma insulin concentration I, and the beta-cell functional mass β. It is possible to show that the parameters p and si are not structurally identifiable: any numerical choice of parameters p and si that have the same product psi are indistinguishable.
Practical identifiability
Structural identifiability is assessed by analyzing the dynamical equations of the system, and does not take into account possible noises in the measurement of the output. In contrast, practical non-identifiability also takes noises into account.
Other related notions
The notion of structurally identifiable is closely related to observability, which refers to the capacity of inferring the state of the system by measuring the trajectories of the system output. It is also closely related to data informativity, which refers to the proper selection of inputs that enables the inference of the unknown parameters.
The (lack of) structural identifiability is also important in the context of dynamical compensation of physiological control systems. These systems should ensure a precise dynamical response despite variations in certain parameters. In other words, while in the field of systems identification, unidentifiability is considered a negative property, in the context of dynamical compensation, unidentifiability becomes a desirable property.
Identifiability also appears in the context of inverse optimal control. Here, one assumes that the data comes from a solution of an optimal control problem with unknown parameters in the objective function. Here, identifiability refers to the possibility of infering the parameters present in the objective function by using the measured data.
Software
There exist many software that can be used for analyzing the identifiability of a system, including non-linear systems:
PottersWheel: MATLAB toolbox that uses profile likelihood for structural and practical identifiability analysis.
STRIKE-GOLDD: MATLAB toolbox for structural identifiability analysis.
StructuralIdentifiability.jl: Julia library for assessing structural parameter identifiability.
LikelihoodProfiler.jl: Julia library for practical identifiability analysis.
See also
System identification
Observability
Model order reduction
Adaptive control
References
Dynamical systems | Structural identifiability | [
"Physics",
"Mathematics"
] | 784 | [
"Mechanics",
"Dynamical systems"
] |
72,324,730 | https://en.wikipedia.org/wiki/Alceon%20Group | Alceon Group is an Australian venture capital, private equity and investment firm. The company was established in 2010 by Trevor Loewensohn and Phil Green.
The company owns Decor Corporation, founded in Melbourne in 1958. It also acquired Marlin Brands in 2017, and Willow Ware Australia, founded in Melbourne in 1887.
Portfolio
Marlin Brands
Alceon Group owns 50% of Marlin Brands with Oaktree Capital Management.
Zanui – Homewares stores
Decor – Food storage containers, brushware and mops
Reva – Pegs
Starmaid – Document storage
Willow – BBQ needs, document storage
Mosaic Brands
In September 2014, Alceon Group attempted a takeover of womenswear retailer Noni B (later renamed Mosaic Brands). However, Alceon was blocked from taking the company private when Gannet Capital acquired a 12 per cent stake in Noni B. Alceon Group owns 36% of Mosaic Brands.
Willow Ware
Willow Ware had its origin in Wilson Brothers Pty, founded by Ralph and Richard, sons of Ralph Wilson, sen., (c. 1826 – 14 June 1901) and Elizabeth Wilson ( – 21 April 1912). With start-up capital from their parents, they began making tin cans in 1887, and constructed a factory in North Melbourne. Ralph Wilson (1865 – 10 December 1930) married Agnes Kirkwood Twaddell (1870–1946) in 1896, and lived at "Benarty", in High Street, Malvern. Ralph seems to have been a respected employer, but nothing has been found of his brother Richard's involvement, except for his retirement in 1906.
Apart from robberies and vandalism, the company was never in the news. It established the "Willow" brand in the 1920s, making Coolgardie safes, billies and other metal cookware, and became W., M., Y., and A. H. Wilson Ltd. The firm later moved to Tullamarine, and now only makes plastic products. Since 2018, the brand has been owned by Decor Corporation, a subsidiary of Marlin Management Services.
References
External links
Alceon Group | Shop Ethical! company profile
Australian companies established in 2010
Private equity firms of Australia
Food preservation
Cooler manufacturers
Vacuum flasks
Camping equipment manufacturers
Holding companies of Australia | Alceon Group | [
"Physics"
] | 465 | [
"Vacuum",
"Matter",
"Vacuum flasks"
] |
72,324,871 | https://en.wikipedia.org/wiki/Kollar%20carp | The Kollar carp (Cyprinus carpio x Carassius auratus) is a hybrid fish obtained by crossing common carp (Cyprinus carpio) and goldfish (Carassius auratus). Described by the Austrian zoologist Johann Jacob Heckel, its binomial name pays tribute to his compatriot, entomologist Vincenz Kollar. Having been considered a separate species from its original relatives, this fish has as synonym Carpio kollarii (Heckel, 1836). Although this carp is most often found in fish farms, they have also been recorded from the wild.
Diet
The Kollar Carp has a wide variety of diet options. It includes aquatic plants, insects, and smaller fish. This type of diet makes it an omnivore and a benthic feeder. It does have pharyngeal teeth which are resemble human molars and therefore help with being able to consume smaller fish, and insects.
References
Georges Cuvier and Achille Valenciennes, t. premier, Paris, F. G. Levrault, 1828, 573 p.( DOI 10.5962/bhl.title.7339, read online [archive]).
Georgia Aquarium https://www.georgiaaquarium.org/animal/common-carp/.
Michel Pascal, Olivier Lorvelec, Jean-Denis Vigne, Philippe Keith and Philippe Clergeau"", Holocene evolution of the fauna of Vertebrés of France: invasions and disappearances, Paris, National Museum of Natural History,No. 154 biological invasions, July 10, 2003, p. 111-332(read online [archive] [PDF], consulted on January 8, 2019).
Cyprininae
Fish hybrids
Intergeneric hybrids | Kollar carp | [
"Biology"
] | 372 | [
"Intergeneric hybrids",
"Hybrid organisms"
] |
72,325,774 | https://en.wikipedia.org/wiki/TQ-15 | The TQ-15 (, lit. Sky Lark 15) is a gas-generator cycle rocket engine burning liquid methane and liquid oxygen under development by Landspace. The most recent version of the TQ engine family, the TQ-15A, is intended to power the second stage of LandSpace's upgraded Zhuque-2 rocket.
History
In October 2022, the construction of a fresh batch of ZQ-2 rockets was announced by LandSpace. A new variant of the TQ family of engines, designated as TQ-15A, was used in the second stage. The weight of the engine was reduced by 400 kg as a result of the elimination of the TQ-11 vernier thrusters, and vectoring is now done with a thrust vector control system that can angle up to four degrees. Additionally, the thrust will be enhanced and equipped with restart capabilities for greater mission profile flexibility.
In March 2024, the first flight-ready TQ-15A was delivered for the assembly of Zhuque-2 Block 2.
On November 27, 2024, an upgraded Zhuque-2E with a TQ-15A engine powering the second stage successfully placed 2 satellites into orbit.
References
Rocket engines of China
Rocket engines using methane propellant
Rocket engines using the gas-generator cycle | TQ-15 | [
"Astronomy"
] | 260 | [
"Rocketry stubs",
"Astronomy stubs"
] |
72,325,950 | https://en.wikipedia.org/wiki/ISO/IEC%205230 | ISO/IEC 5230 (known as OpenChain) is an international standard on the key requirements for a high-quality open source license compliance program. The standard was published jointly by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC) in late 2020. The standard is based on the Linux Foundation OpenChain Specification 2.1. It focuses on software supply chains, easier procurement and license compliance. Organizations that meet the requirements of the standard can self-certify to ISO/IEC 17021, from an accredited certification body or after successfully completing an audit.
How the standard works
Most organizations and software products rely on numerous open source components made by third parties, such as frameworks, libraries and containers, coming from diverse and often unaffiliated sources. This is akin to a supply chain in a brick-and-mortar environment and making sure the supply chain is as reliable as possible is considered important from an operational, legal and security standpoint. Upon this premise, a number of players have decided to establish the ground rules for an organization to deal with open source software at whichever level of the supply chain they operate. A working group under the umbrella of the Linux Foundation, the OpenChain project. Later, when reaching the 2.0 version, the norms were presented for approval as an ISO/IEC standard.
According to the standard, in order to use open source components effectively, organization must be aware of and comply with all the components involved, the associated open source licenses, and obligations such as copyleft. ISO/IEC 5230 aims to establish a non-prescriptive common understanding of what needs to be addressed within a quality open source compliance program. This makes ISO/IEC 5230 applicable across many industries and organizations and provides benefits to procurement and software supply chains, as open source software tends to be very cumbersome in legal contracts and procurement.
The main topics covered by ISO/IEC 5230 and OpenChain-2.1 are:
Existence of an open source policy
Competencies of program participants (e.g., legal training for specific tasks).
Awareness of open source risks among all program participants
A clearly defined scope, e.g. only specified areas and product lines
Understand and collect licensing obligations for relevant use cases.
Access for external open source requests (e.g. to the OSS authors).
Compliance offices equipped with sufficient resources
Generate a Bill of Material
License compliance process (e.g., documents meeting obligations)
Archiving and provision of compliance artifacts
A guideline for community engagement and contributions
ISO/IEC 5230 does not define how exactly most of the tasks are to be performed, such as whether snippet scanning, revalidation of declared open source licenses is required, and what the compliance artifacts should look like. However, SPDX is now an ISO standard (ISO/IEC 5962) and is mentioned in ISO/IEC 5230 as an example of compliance artifacts.
Certification
A high-quality open source compliance program can be certified as compliant with ISO/IEC 5230 by a number of accredited registrars worldwide.
In some countries, the bodies that verify the conformity of management systems to certain standards are referred to as "certification bodies", while in others they are usually referred to as "registration bodies", "assessment and registration bodies", "certification/registration bodies" and sometimes "registrars".
ISO/IEC 5230 certification, like other ISO management system certifications, typically involves a three-step external audit process defined in ISO/IEC 17021:
Stage 1 is a preliminary, informal review of the open source compliance program, verifying, for example, the existence and completeness of key documents such as the organization's open source policy, clearing process, and staffing. This phase serves to familiarize the auditors with the organization and vice versa.
Stage 2 is a more detailed and formal compliance audit, where the open source compliance program is independently audited against the requirements set out in ISO/IEC 5230. Auditors look for evidence to confirm that the management system has been properly designed and implemented and is actually in operation. Certification audits are usually performed by ISO/IEC 5230 lead auditors. Passing this phase results in the open source quality program being certified as compliant with ISO/IEC 5230.
Continuous means that follow-up reviews or audits are conducted to confirm that the organization continues to be compliant with the standard. Maintenance of certification requires periodic re-audits to confirm that the quality open source compliance program continues to function as specified and intended. These should occur at least annually, but are often conducted more frequently (in consultation with management), especially while the Quality Open Source Compliance Program is still under development.
Additionally, ISO/IEC 5230 is functionally identical to OpenChain 2.1, which enables free self-certification via the project's web app.
Dissemination
On October 19, 2020, the Eclipse Foundation announced that it is the first open source foundation to be certified to ISO/IEC 5230. Several companies, including SAP, Toshiba, Samsung Electronics and LG Electronics have publicly announced their conformance to OpenChain.
External links
ISO/IEC 5230:2020-12 Information technology - OpenChain specification
OpenChain official website
OpenChain official translations
OpenChain Self Certification
Shane Coughlan: A Recap of the OpenChain Project.
OpenChain project on GitHub
Source
First version of this article was translated from the article on German Wikipedia.
References
ISO standards
Open source
Information assurance standards | ISO/IEC 5230 | [
"Technology"
] | 1,129 | [
"Computer standards",
"Information assurance standards"
] |
72,326,221 | https://en.wikipedia.org/wiki/Submarine%20detection%20system | Submarine detection systems are an aspect of antisubmarine warfare. They are of particular importance in nuclear deterrence, as they directly undermine one of the three arms of the nuclear triad by making counter-force attacks on submarines possible.
Types of system
They break down into two broad categories; acoustic and non-acoustic.
Acoustic systems in turn break down into active sonar systems and passive sonar systems designed to detect the acoustic signature of submarines such as SOSUS.
Non-acoustic systems can work on a variety of different physical principles, including the use of magnetic anomaly detectors and systems such as SOKS, which are believed to work by detecting phenomena such as trace chemicals, heat changes, and radioactivity left in a submarine's wake. There is evidence that some Royal Navy submarines are fitted with wake-detection systems.
References
Further reading
Soviet Antisubmarine Warfare: Current Capabilities And Priorities, 1972 CIA report, declassified and published in 1995
External links
Submarine Detection and Monitoring: Open-Source Tools and Technologies, at NPI.org
Anti-submarine warfare
Military technology
Nuclear warfare | Submarine detection system | [
"Chemistry"
] | 218 | [
"Radioactivity",
"Nuclear warfare"
] |
65,139,667 | https://en.wikipedia.org/wiki/LY-266%2C097 | LY-266,097 is a research ligand which acts as a potent and selective antagonist for the 5-HT2B receptor, with more than 100x selectivity over the related 5-HT2A and 5-HT2C receptor subtypes. However, other sources have stated that LY-266,097 is actually a biased agonist of the receptor, selective for Gq signaling but not β-arrestin2. The drug has been used to study the role of the 5-HT2B receptor in modulating dopamine release in the brain, as well as its involvement in other processes such as allodynia.
References
5-HT2B agonists
5-HT2B antagonists
Biased ligands
Chlorobenzene derivatives
Tryptamines | LY-266,097 | [
"Chemistry"
] | 171 | [
"Pharmacology",
"Medicinal chemistry stubs",
"Signal transduction",
"Biased ligands",
"Pharmacology stubs"
] |
65,140,300 | https://en.wikipedia.org/wiki/Differential%20effects | Differential effects play a special role in certain observational studies in which treatments are not assigned to subjects at random, where differing outcomes may reflect biased assignments rather than effects caused by the treatments.
Definition
For two treatments, differential effects is the effect of applying one treatment in lieu of the other. Differential effects are not immune to differential biases, whose possible consequences are examined by sensitivity analysis.
Methods
In statistics and data science, causality is often tested via regression analysis. Several methods can be used to distinguish actual differential effects from spurious correlations. First, the balancing score (namely propensity score) matching method can be implemented for controlling the covariate balance. Second, the difference-in-differences (DID) method with a parallel trend assumption (2 groups would show a parallel trend if neither of them experienced the treatment effect) is a useful method to reduce the impact of extraneous factors and selection bias. The differential effect of treatments (DET) was explored using several examples and models.
In the biomedicine area, differential effects of early hippocampal pathology were investigated on episodic and semantic memory. The differential effects of apolipoproteins E3 and E4 were also examined on neuronal growth in vitro.
See also
Randomization
Causality
Causal inference
Differential outcomes effect
References
Randomness
Inductive reasoning
Philosophy of statistics | Differential effects | [
"Mathematics"
] | 276 | [
"Philosophy of statistics"
] |
65,140,856 | https://en.wikipedia.org/wiki/Forbidden%20Dream | Forbidden Dream () is a 2019 South Korean historical drama film directed by Hur Jin-ho and written by Jung Bum-shik and Lee Ji-min. Screenplay by Choi Gun-ho. Based on a true story, it portrays Sejong the Great (Han Suk-kyu), king of the Joseon dynasty of Korea, and his relationship with his greatest scientist, Jang Yeong-sil (Choi Min-sik). It made its international debut at the 2020 New York Asian Film Festival in August 2020.
Synopsis
King Sejong (Han Suk-kyu), the greatest ruler in Chosun history seeks to enhance national prosperity and military power through astronomy with the help of his greatest scientist, Jang Yeong-sil (Choi Min-sik). For twenty years they forged a relationship but due to an incident, Jang Yeong-sil was removed from his post and disappeared completely.
Cast
Choi Min-sik as Jang Yeong-sil
Han Suk-kyu as Sejong
Park Sung-hoon as Lee Hyang
Shin Goo as Hwang Hui
Kim Hong-fa as Yi Cheon
Huh Joon-ho as Cho Mal-saeng
Kim Tae-woo as Jeong Nam-son
Kim Won-hae as Cho Soon-saeng
Im Won-hee as Lim Hyo-don
Yoon Je-moon as Choi Hyo-nam
Jeon Yeo-been as Sa-im
Oh Hee-joon as Young eunuch
Accolades
See also
The King's Letters
References
External links
2019 films
2019 drama films
2010s historical drama films
2010s Korean-language films
Drama films based on actual events
Films about astronomy
Films about scientists
Films directed by Hur Jin-ho
Films set in Joseon
Lotte Entertainment films
South Korean films based on actual events
South Korean historical drama films
2010s South Korean films
Hive Media Corp. films | Forbidden Dream | [
"Astronomy"
] | 383 | [
"Films about astronomy",
"Works about astronomy"
] |
65,140,928 | https://en.wikipedia.org/wiki/Timeline%20of%20the%20L%C3%BD%20dynasty | This is a timeline of the Lý dynasty, which ruled Đại Cồ Việt (1009–1054), and then the renamed Đại Việt (1054–1226).
11th century
12th century
13th century
References
Bibliography
*
Vietnam history-related lists
Historical timelines
Lý dynasty | Timeline of the Lý dynasty | [
"Physics"
] | 61 | [
"Wikipedia timelines",
"Spacetime",
"Physical quantities",
"Time"
] |
65,141,595 | https://en.wikipedia.org/wiki/Uzbekcosmos | The Space Research and Technology Agency under the Ministry of Digital Technologies of the Republic of Uzbekistan (Uzbek: O'zbekiston Respublikasi Raqamli texnologiyalar vazirligi huzuridagi Kosmik tadqiqotlar va texnologiyalar agentligi) also known as Uzbekspace Agency (Uzbek: "O'zbekkosmos" agentligi) is the official Uzbek state space agency. The agency is officially tasked with the development and implementation of a unified state policy and strategic directions in the field of space research and technology. Uzbekspace Agency was formed by decree of the President of the Republic of Uzbekistan Shavkat Mirziyoyev on August 30, 2019.
References
Space agencies
Space programs by country | Uzbekcosmos | [
"Engineering"
] | 165 | [
"Space programs",
"Space programs by country"
] |
65,141,659 | https://en.wikipedia.org/wiki/Criminal%20Justice%20%28Public%20Order%29%20Act%201994 | The Criminal Justice (Public Order) Act 1994 is legislation that covers public order offences in the Republic of Ireland. It is the main legislation on the matter of public order, deals with how people behave in public places and provides for crowd control at public events.
Gardaí have powers to arrest people without warrant for most offences under the act. In particular, someone suspected of committing a public order offence may be asked their name and address, and arrested without warrant upon refusal.
Offences
Intoxication in a public place
Intoxication in a public place is an offence under section 4 of the act. If a Garda suspects a person of being intoxicated they can confiscate any intoxicating substance from them.
The penalty is either a fixed charge of €100 or a maximum class E fine of €500 if the Gardaí decide to prosecute and there is a conviction.
Disorderly conduct in a public place
It is an offence to engage in offensive conduct between the hours of midnight and 7am or at any time if a Garda asks you to.
Offensive behaviour is unreasonable behaviour likely to cause serious offence or annoyance to other people. This is to deal with disorderly behaviour that falls short of threatening behaviour but which could still adversely affect people's lives.
An example is people shouting loudly after leaving a night club, which could annoy local residents.
The penalty for this is either a fixed charge fine of €140 or the maximum class D fine if the Gardaí prosecute and there is a conviction.
A person must give their name and address when asked for them if they want this offence treated as a fixed charge offence. Someone who doesn't give their name and address can be arrested without warrant and convicted of a summary offence for which the maximum fine is a class C fine.
Threatening, abusive or insulting behaviour in a public place
It is an offence to engage in threatening, abusive or insulting behaviour in a public place with the intent of breaching the peace.
An example is someone trying to provoke a fight with someone else using insults.
If found guilty of such an offence, someone can be given a class D fine and prison sentence of up to three months.
Begging in an intimidating or threatening manner
It is an offence to beg in an intimidating or threatening manner. Someone found guilty of this offence is liable on summary conviction to a class E fine or up to one month in prison or both.
Gardaí can direct someone to leave certain areas if they are begging there - e.g. a shop entrance or at an ATM.
It is also an offence to organise or direct someone else to beg. A summary conviction can mean a class A fine, up to 12 months in prison or both.
Distributing or displaying threatening, abusive, insulting or obscene material in a public place
It is an offence to distribute or display threatening, abusive, insulting or obscene material in a public place. A conviction can result in a class D fine, a prison sentence of up to three months or both.
Because the interpretation of something being obscene may be subjective, courts will apply the "ordinary man" test when deciding whether material is obscene or not.
Failure to comply with the direction of a member of the Garda Síochána
It is an offence to not comply with a Garda's request to stop behaving in a way that the Garda believes endangers the safety of others, their property or the public peace. Gardaí can ask people to "move on" to avert potential trouble.
It is an offence not to comply with these directions without a reasonable excuse or lawful authority to do so. Anyone convicted is liable on summary conviction to a class D fine, a maximum prison term of six months or both.
Wilful obstruction
It is an offence to prevent a person or their vehicle from passing freely in a public place without legal authority or a reasonable excuse. The penalty is a fine of up to €400.
Gardaí do not have a power to arrest for this offence, they can direct people to stop the obstruction. Failure to comply with the direction is an offence.
Entering a building with intent to commit an offence
It is an offence to enter a building or its vicinity with the intent to commit an offence or interfere with property. It suffices to be on the property as this offence is defined, but the prosecution must prove intent.
Anyone convicted will, on summary conviction, be liable for a class C fine, a maximum prison term of 6 months or both.
Trespass
It is an offence to trespass in a way that is likely to cause fear in someone else. This does not include any intent to commit crime or interfere with property. Someone found guilty of this crime is liable on summary conviction to a class C fine, a maximum term of imprisonment of 12 months or both.
A Garda can direct anyone they fine trespassing in such a manner to leave the area in a peaceable and orderly manner. Failure to comply with such a direction without a reasonable excuse or lawful authority is an offence. Anyone found guilty of this offence is liable to a class D fine, a maximum of six months imprisonment or both.
Riot
Riot is one of the most serious public order offences.
It is defined as when:
12 or more people use or threaten to use violence
with common purpose
their conduct would cause a reasonable person to fear for their safety or for that of someone else
they actually used violence.
This offence can be committed in a public or private place. It can be used in situations where people assemble in protest and their behaviour becomes unlawful violence. The penalty is an unlimited fine, a period of imprisonment for up to 10 years or both.
Violent disorder
Violent disorder is a similar offence to riot, but is of a lesser degree.
It is defined as when:
3 or more people are gathered at a place
they use or threaten to use violence
their conduct would cause someone of reasonable firmness who was present to fear for their own safety or that of someone else.
Apart from the number of people involved the differences between riot and are that violence must have been used in riot but not in violence disorder and that in riot the group must share a common purpose which violent disorder does not require.
The penalty is an unlimited fine, a period of imprisonment for up to 10 years or both.
Affray
This offence is when two or more people use or threaten to use unlawful violence between each other and their conduct would cause someone of reasonable firmness who was present to fear for their own safety or that of someone else. The violence must be between those involved and not aimed at innocent third parties. It requires unlawful violence, threats alone do not suffice.
The penalty is an unlimited fine, a period of imprisonment for up to 5 years or both.
Blackmail, extortion and demanding money with menaces
It is an offence for a person to make unwarranted demands with menaces to make personal gains for themselves or someone else or with the intent to cause a loss for someone else.
An exception exists if:
the person making the demands believes they have reasonable grounds for making them
they believe the use of menaces is a proper way of enforcing the demand.
The courts have held that "menaces" are to be interpreted broadly.
The penalty is an unlimited fine, a period of imprisonment for up to 14 years or both.
Assault with intent to cause bodily harm or commit an indictable offence
While the main law that deals with assault is the Non-Fatal Offences Against the Person Act 1997, section 18 of this act creates another offence of assault with intent to cause bodily harm or to commit an indictable offence. It covers aggravated assaults when there is intent to injure or commit an indictable offence.
The penalty is an unlimited fine, a period of imprisonment for up to 5 years or both.
Assault or obstruction of a peace officer
It is an offence to threaten a peace officer or someone providing medical services at a hospital.
Peace officers are:
members of the Garda Síochána
members of the Fire Brigade
Ambulance personnel
Prison officers
members of the Defence Forces.
This covers assaults on:
a peace officer or someone providing medical services at a hospital
anyone assisting a peace officer or someone providing medical services.
It is also an offence to assault such people to prevent the lawful arrest or detention of someone for an offence.
The penalty is an unlimited fine, a period of imprisonment for up to 7 years or both.
Someone could also be guilty of this offence for obstructing:
a peace officer or someone providing medical services at a hospital
anyone assisting a peace officer or someone providing medical services.
Someone found guilty of this crime is liable on summary conviction to a class C fine, a maximum term of imprisonment of 6 months or both.
References
External links
Criminal Justice (Public Order) Act, 1994 at Irish Statute Book
1994 in Irish law
Acts of the Oireachtas of the 1990s
Anti-social behaviour | Criminal Justice (Public Order) Act 1994 | [
"Biology"
] | 1,795 | [
"Anti-social behaviour",
"Behavior",
"Human behavior"
] |
65,146,708 | https://en.wikipedia.org/wiki/BevQ | BevQ is a queue management mobile application developed by Faircode Technologies of Kochi, Kerala. It is provided by the Kerala State Beverages Corporation under Government of Kerala.
History
This app was released together by the Government of Kerala and the Kerala State Beverages Corporation in order to implement social distancing in the liquor stores Kerala in the case of the COVID-19 pandemic in Kerala and to reduce the congestion of people. The BevQ App was released by Faircode Technologies on 27 May 2020 on the Google Play Store.
In January 2021, the app was withdrawn as bars had opened.
In June 2021, there was a commitment from the Kerala CM that the App will be relaunched again. It has been reported that over 132,000 new users downloaded the app in the 48 hours after the announcement.
Achievements
The BEVQ app, which works only in the state of Kerala, beat all other Indian food and drink apps in 2020 to see the highest growth in year-on-year sessions, according to the State of Mobile 2021 report by App Annie. The app even beat the likes of Domino’s, which is used all across India.
Around 300 government Liquor shops and 900 private liquor shops were enlisted in the platform. More than 200 million unique users registered in the platform. About 250,000 tokens were given out a day.
References
External links
Developer website
Android (operating system) software
Mobile applications | BevQ | [
"Technology"
] | 284 | [
"Mobile software stubs",
"Mobile technology stubs"
] |
65,148,027 | https://en.wikipedia.org/wiki/Statactivism | The French movement of statactivism advocates for the mobilization of statistics in support to social movements and agendas.
Content
The program of French statactivistts is to ‘fight against’ as well as ‘fight with’ numbers, using a variety of possible strategies:
‘Statistical judo’. This is a strategy of self-defence, whereby existing measures are ‘gamed’ as prescribed by the Goodhart's law;
Denouncing the inadequacy or bias or unfairness of existing indicators and measures, e.g. from official statistics of poverty or inequality;
Developing alternative indicators to substitute for those above;
Identifying social contexts and problems which are invisible to existing statistics
Statactivism's intellectually belongs to the tradition of sociology of numbers.
Following Alain Desrosières and Theodore Porter, statactivists use statistics as a “tool of weakness”, which offer to the weak members of society the opportunity to act against their oppression by making injustice visible.
See also
Sociology of quantification
Ethics of quantification
Society for the Social Studies of Quantification - SSSQ
Data activism
References
Statistical organizations
Quantification (science)
Mathematical and quantitative methods (economics) | Statactivism | [
"Mathematics"
] | 241 | [
"Quantity",
"Quantification (science)"
] |
65,148,231 | https://en.wikipedia.org/wiki/Maria%20Watkins | Marja "Maria" Ludwika Watkins (; 2 December 19182 September 2010) was a defence electronics engineer, lecturer and President of the Women's Engineering Society.
Early life
Ziff was born on 2December 1918 in Vienna, Austria, and grew up in the Polish city of Lvov. Her parents were of Ukrainian descent; her father was director of a bank, and her mother was a research chemist at Lvov University.
Education
In 1938, Ziff applied to study electrical engineering at the University of Edinburgh. She was accepted and moved to Scotland, surprising the professor who had offered her a place, as he had believed her application was from a Polish man. She became the first woman to study electrical engineering there. She joined the Women's Engineering Society on her arrival in the UK in 1939. In 1941, she graduated from the University of Edinburgh with a degree in Electrical Engineering (Communications). As the situation worsened in Europe, her family refused to join her. Following the invasion of Poland by Russia and Germany, her parents and grandparents died in the concentration camps, only her sister surviving. She never felt able to return to Poland.
Career
In 1942, Ziff became a technical assistant at Johnson and Phillips Ltd. The company made cabling and navigation items for aircraft, and she worked on technical problems of their distribution systems. Her job was varied, including working as a research assistant for new airplane guidance systems, to supervising the repair of overhead power cables shot down by drunken soldiers or repairing electrical exchanges damaged by bombings. She was one of the assistants to Jules Thorn, the founder of Thorn Electrical Industries, one of the United Kingdom's largest electrical businesses. She lived in Blackheath, London during the latter part of the Second World War, volunteering as an air raid warden in the evenings. During this time she was working on research for the PLUTO Pipeline Under The Ocean project and on a secret airplane guidance system.
In 1947, a year after her marriage, Watkins was appointed a lecturer at South East London Technical College. In 1959, she became a lecturer at Northampton College of Advanced Technology, now the City University, and was later promoted to Senior Lecturer, working there until 1985. She was a member of Council and Senate of City University for three years, and a member of Council and the Qualification board of the Institution of Electrical Engineers from 1976 to 1979.
In 1981, Watkins attended the International Conference of Women Engineers and Scientists (ICWES) in Bombay, combining it with travel around India and Nepal. She also attended the 1991 ICWES in Coventry. She undertook research in medical electronics and published at least 13 papers on these subjects. She was a visiting professor at Worcester Polytechnic Institute, Boston, USA from 1973 to 2010, spending a term teaching there in 1975. She was an advocate for international higher education programmes and founded a number of programmes for visiting students from the USA.
Memberships
Watkins was a Liveryman and senior steward of the Worshipful Company of Scientific Instrument Makers, and became a Freeman of the City of London. She was elected a Life Fellow of the Royal Society of Arts and a Fellow and active member of the Institution of Electrical Engineers. She was a long-term member of the Women's Engineering Society (WES) and took an active part in the London Branch. She played a key part in WES's submission to the Finniston Enquiry, heading up the education sections of the submission.
Watkins was a driving force in its work encouraging schoolgirls to consider engineering as a career, and acted as WES's careers officer for some years. She was elected WES President from 1980 to 1981, succeeding Veronica Milligan and being succeeded by Rosemary West. In 1981, she gave the annual Verena Holmes lecture entitled Chips for the Disabled, which examined how engineering could help support people living with disabilities. In 1984, she donated the Watkins Medal to WES to be awarded to the best female engineering graduate of the year. She held tea parties for women engineering students at City University and encouraged them to join WES for the support it could offer their careers.
Personal life
On 22February 1946, Ziff married Flight lieutenant Thomas "Tom" Brown Watkins (19211961), of the Royal Air Force and Leith, at St Saviour's Church, Lewisham. He was a fellow engineering student at Edinburgh and had returned from active service in the Second World War. In 1947, they made their home in Sydenham, joined by her younger sister, who had survived the war, and her mother-in-law. The couple had two sons, born in 1947 and 1951. She took his surname, and was often called Maria rather than Marja from this period onwards.
Death
Maria Watkins died in on 2September 2010 at Highgate, London, and was cremated on 13September 2010. Her obituary was published in The Woman Engineer journal.
References
1918 births
2010 deaths
Austrian women engineers
Electronics engineers
Engineers from Vienna
Presidents of the Women's Engineering Society
Women's Engineering Society
Austrian emigrants to the United Kingdom
Academics of City, University of London
Alumni of the University of Edinburgh
20th-century Austrian engineers
21st-century Austrian engineers
20th-century women engineers
21st-century women engineers | Maria Watkins | [
"Engineering"
] | 1,061 | [
"Electronics engineers",
"Electronic engineering"
] |
65,151,168 | https://en.wikipedia.org/wiki/Loam%20molding | Loam molding was formerly used for making cast iron or bronze cannon and is still used for casting large bells.
Loam (pronounced 'low-m') is a mixture of sand and clay with water, sometimes with horse dung (valuable for its straw content), animal hair or coke. The object of including dung or hair was to make the mould permeable and allow gas (such as steam) to escape during casting.
The mold for a cylindrically symmetrical object, such as a cannon, is built up in stages around a spindle, to which is fixed a strickle board with the shape of the eventual casting. The mold also has provision for the casting of a gunhead, beyond the muzzle of the cannon, into which slag can float during casting. If the object is to be hollow, a straw rope is wound around the spindle and covered in a friable material to the dimensions of the exterior of the cannon, the strickle board being turned on the spindle to ensure it is cylindrical. Decorative elements and models of the trunnions are then attached. This is then covered in a thick layer of loam. The mold is then fired. After this the straw rope is then pulled out with the rest of the material used to form the shape of the cannon.
The mould is then mounted vertically in a casting put in front of the furnace. If the cannon is to be cast hollow, a core is mounted in the mould. The furnace was then tapped and metal run into the mold. The mold is then broken off the casting. The gunhead is cut off, and the bore of the cannon reamed out using a boring mill.
The process for the cylinder for a steam engine would be similar. The process for casting a bell is of the same nature, but the procedure is necessarily different.
References
Metalworking
History of metallurgy
Metallurgy | Loam molding | [
"Chemistry",
"Materials_science",
"Engineering"
] | 389 | [
"Metallurgy",
"History of metallurgy",
"Materials science",
"nan"
] |
65,154,948 | https://en.wikipedia.org/wiki/Matrix%202%20of%205 | Matrix 2 of 5 (also known as Code 2 of 5 Matrix.) is a variable length, discrete, two width symbology. Matrix 2 of 5 is a subset of two-out-of-five codes. Unlike Industrial 2 of 5 code, Matrix 2 of 5 can encode data not only with black bars but with white spaces.
Matrix 2 of 5 was developed in 1970-х by Nieaf Co. in The Netherlands and commonly was uses for warehouse sorting, photo finishing, and airline ticket marking.
Matrix 2 of 5 can encode only digits 0-9. Matrix 2 of 5 can include optional check digit. Most of barcode readers support this symbology.
Encoding
Matrix 2 of 5 is a subset of two-out-of-five codes family and uses wide and narrow elements for encoding. Unlike previously developed Industrial 2 of 5 it uses both black bars and white spaces for data encoding. However, it has lower density then Interleaved 2 of 5 code, because it is discrete symbology and requires additional space between data patterns. Main advantage over Interleaved 2 of 5 codes is ability to encode odd number of characters in message.
Matrix 2 of 5 encodes only digits from 0 to 9 in three black bars and two white spaces, with every data pattern split by additional white space. Matrix 2 of 5 could include optional checksum character which is added to the end of the barcode.
Matrix 2 of 5 features:
character set is a number (0-9);
encoding density moderate: barcode length on 11% longer than Interleaved 2 of 5 symbology and on 82% than Code 128;
variable length of symbol;
can include optional checking character.
Four starting bars and spaces in pattern have own weights which encode value of the symbol (except zero). Also, last black bar is used as parity bit to avoid single error. Value of the symbol is a sum of nonzero weights of four first pattern elements.
N - narrow black bar or white space.
W - wide black bar or white space.
Narrow to wide components difference could be from 1/3 to 2/5.
The barcode has the following physical structure:
1. Quiet zone 10X wide
2. Start character
3. Variable length digit characters, properly encoded
4. Optional check digit
5. Stop character
6. Quiet zone 10X wide
Checksum
Matrix 2 of 5 may include an optional check digit which is calculated as mod 10/3 checksum. Because specification of Matrix 2 of 5 does not require checksum any other checksum types could be used with the symbology. However mod 10/3 checksum is most common.
,
where is the most right data digit.
Example for the first 6 digits 423456:
Result: 4234562 barcode
Datalogic 2 of 5
Data Logic 2 of 5 (also known as Code 2 of 5 Datalogic, China Post Code) is proprietary Chinese version of Matrix 2 of 5 symbology developed by Datalogic. It has difference from Matrix 2 of 5 code only in start/stop patterns usage and, in this way, it has all advantages and issues of Matrix 2 of 5.
Datalogic 2 of 5 was used mostly in Chinese Postal Services. Some readers currently still support this symbology
N - narrow black bar or white space.
W - wide black bar or white space.
See also
Automated identification and data capture (AIDC)
Barcode
Code 2 of 5
Datalogic
Interleaved 2 of 5
References
External links
Datalogic 2 of 5 description
Matrix 2 of 5 and Datalogic 2 of 5 generator
Matrix 2 of 5 structure
Automatic identification and data capture
Barcodes
Encodings | Matrix 2 of 5 | [
"Technology"
] | 738 | [
"Data",
"Automatic identification and data capture"
] |
66,404,390 | https://en.wikipedia.org/wiki/Wimkin | Wimkin is an alt-tech social network that claims to promote free speech. The site describes itself as "100% uncensored social media". Wimkin was launched in August 2020 and was founded by Jason Sheppard.
As of January 2021, Wimkin had 300,000 users.
History
Wimkin launched in August 2020 after being founded by Jason Sheppard.
On January 12, 2021, Apple removed Wimkin from the Apple App Store for hosting violent content, including calls for a civil war and the arrest of then-Vice President Mike Pence. Sheppard stated that Wimkin had removed the violent content after Apple reported it to them. However, Apple claimed that they "continued to find direct threats of violence and calls to incite lawless action" on Wimkin. After Wimkin was removed from the App Store, Wimkin's website was hit with a DDoS attack.
Google subsequently removed Wimkin from the Google Play Store, with a Google spokesperson saying of the ban that, "We don't allow apps that depict or facilitate gratuitous violence or other dangerous activities." In response, Sheppard accused Google of treating Wimkin unfairly, stating in an email that, "We're being treated entirely unfairly and if we aren't reinstated when we've worked tirelessly to comply and become a better platform, we will be seeking legal remedy to at the very least, shed some light into this tyrannical monopoly."
In a message on Wimkin's website following the removals, the company said that "We are working on getting back in both Apple Store and Google Play." Wimkin has since returned to both the App Store and Google Play.
After Parler, another social network, was pulled offline by its host Amazon Web Services on January 11, former users of that site started migrating to Wimkin. In the twelve days following the storming of the United States Capitol, Wimkin claimed that its userbase had grown by 20 percent, amounting to around 55,000 new users.
Users and content
While Wimkin has groups relating to mundane topics, such as pets and traveling, Wimkin also has groups relating to fringe content, such as the far-right conspiracy theory QAnon. There were also posts and a group on Wimkin attempting to organize a "Million Militia March" for January 20, 2021 on Inauguration Day, but the posts and group were removed.
In January 2021, David Eberti of The Wall Street Journal found posts on Wimkin comparing Democrats with Nazis and a meme saying "If you don't believe in violence, get ready to hide behind someone who does."
Moderation
Wimkin prohibits pornography, nudity, harassment, and inciting violence. The site also does not fact-check posts.
Reception
In January 2021, Chris Tye from WBBM-TV described Wimkin as a platform "used by members of the so-called Trump celebrity class." Also in January, Anthony Cuthbertson of The Independent called Wimkin "yet another social media app popular with far right users".
Design
According to SFGate, Wimkin functions like a combination of Twitter and Facebook, with users of the site being allowed to post to a wider audience, comment and like other posts, and join groups.
References
Real-time web
Delisted applications
Conspiracist media
Social networking websites
Online companies
Alt-tech
Internet properties established in 2020 | Wimkin | [
"Technology"
] | 714 | [
"Real-time web",
"Real-time computing"
] |
66,405,338 | https://en.wikipedia.org/wiki/Yeshimabeit%20Milner | Yeshimabeit "Yeshi" Milner is an American technologist and activist. She is the executive director and co-founder of Data for Black Lives.
Early life and education
Yeshimabeit Milner grew up in Miami, Florida. Starting in her late teens, Milner became involved in activism and data science. She worked with the Power U Center for Social Change as a high school senior. Milner attended Brown University, graduating in 2012 with a BA degree in Africana Studies.
Career
In 2013 at age 22, after returning to Miami after college, Milner started working with the Power U Center for Social Change and looking at Black infant mortality rates locally in trying to understand why they were disproportionately so high. They were able to retrieve data from 300 mothers, and as a result changed local policy.
One of her classmates at Brown University was mathematician Lucas Mason-Brown, together they founded Data for Black Lives in November 2017. The Data for Black Lives (D4BL) annual conference was started in 2018 by Yeshimabeit Milner and Lucas Mason- Brown. They use the slogan, "Abolish Big Data!" with hopes to redesign big data and to "put data into the hands of those who need it most". In 2020, the group was able to compile state-level data about the impact of COVID-19 on Black people and are working on compiling a nationwide database of technologies used by police departments. In 2021, Milner co-wrote a research piece for Demos on algorithmic racism from Big Tech companies.
Awards and accolades
Milner served on the board of the Highlander Research and Education Center in Tennessee. In 2018, she was awarded a Roddenberry Foundation Fellowship, which honors and invests in extraordinary people who can change the world. In 2020, Data for Black Lives and its founders were awarded the Forbes 30 Under 30 and the New York Times 2020 Good Tech Awards.
See also
African-American women in computer science
References
External links
Ashoka fellow profile
Echoing Greens fellow profile
Brown University alumni
People from Miami
21st-century African-American scientists
Living people
African-American activists
Women data scientists
American data scientists
Year of birth missing (living people)
Data activism
American social entrepreneurs
21st-century African-American academics
21st-century American academics | Yeshimabeit Milner | [
"Technology"
] | 465 | [
"Data",
"Data activism"
] |
66,405,666 | https://en.wikipedia.org/wiki/Palm%20cooling | Palm cooling (often referred to as palmar cooling) is a type of recovery intervention that involves cooling the palm of the hand during rest periods between bouts of strenuous physical activity. The palm cooling modality can be used to moderate increases in core temperature resulting from the level of physical activity, the wearing of protective clothing or a combination of both, for example in the activities of military personnel or firefighters.
Sporting activities, for example during timeouts of basketball or at half time in a game of football, where recovery time is limited, is another example where the level of physical activity combined with or without high ambient temperature can lead to raised core temperature. In these circumstances palm cooling can be used as it is important that the cooling intervention does not chill major muscle groups, which need to be kept warm to optimize performance when the physical activity is resumed.
There is some evidence of palm cooling during rest periods delaying the onset of fatigue, which is a major precursor of injury and an inhibitor of performance. Palm cooling is also used for strength & conditioning, for example between sets in a weight training programme or where obese subjects are taking part in a weight loss exercise programme.
Background
Thermoregulation
Human physiology involves a complex thermoregulation system for moderating core temperature.
In areas of glabrous, that is non-hairy, skin there are special blood vessels called arteriovenous anastomoses, or AVAs, which act as the body's radiators by allowing blood to reach the venous plexus close to the skin surface without going through capillaries and hence facilitate heat transfer.
These AVA's are common in mammals, for example in dogs the AVAs are concentrated in their tongues and in bears the nose is a key radiator of heat. In humans and apes the AVAs are concentrated in the palms of the hands, the soles of the feet and the upper face.
It is more practical to apply a cooling medium to the palms of the hands, rather than to the soles of the feet or the face, so cooling the palms became the focus for researchers.
TRPs
The human skin contains Transient Receptor Potential Channels (TRPs), which are activated by heat, cold, vibration, pressure and some chemicals such as menthol & camphor as well as some spices such as allicin (found in garlic) and capsaicin (found in chili peppers) etc. These TRPs are connected to the spinal canal and some research has shown that they can play an important role in moderating pain and creating a feel good factor by stimulating the release of dopamine and serotonin in the brain.
Some researchers have postulated that palm cooling has a neural impact alongside the mediation of blood temperature. TRPs could play a role in producing this neural impact.
History
The palm cooling concept was developed at Stanford University having evolved from research in the 1990s into palm warming for hypothermic individuals. Core temperature mediation via palm cooling was revisited in the early 2000s, following a commission by the US Military research facility DARPA (Defense Advanced Research Projects Agency) to conduct research into moderating heat stress.
The lead researchers at Stanford were the human thermoregulation specialists, Professor Craig Heller and Dr Dennis Grahn, who as part of the research project developed the Stanford Glove device, which facilitated palm cooling, or palm heating, while simultaneously applying a mild vacuum, that is a slight negative pressure.
The principle behind the use of slight negative pressure was to encourage additional blood flow to the skin in the palm, which was simultaneously cooled through conduction by a cooling medium flowing through a pad that the palm was placed on within the glove.
Research into the efficacy of palm cooling has been conducted at Stanford University, University of New Mexico, Humboldt State University, Ohio State University and the University of Tulsa; and in Australia at the University of Western Sydney and Charles Sturt University. Studies have been conducted into the use of palm cooling for strength & conditioning, for endurance activities and for weight loss in obese subjects (for whom prolonged physical activity can be challenging).
Equipment
There are now a wide variety of palm cooling devices available and they are gaining acceptance among fitness enthusiasts and high level sports teams and programs. The devices vary in a few specific ways. Those that use negative pressure (mild vacuum), those that operate in atmospheric pressure, those that include a self cooling system and others that need to be re-cooled after extended periods of use.
Using Negative Pressure
Palm cooling devices, such as the Stanford Glove or RTX Core Control Cooling device (RTX = Rapid Thermal eXchange), use mild vacuum while cooling the palm through conduction via a cooling medium which flows through a pad upon which the palm of the hand is placed inside the glove.
The theory behind the use of a mild vacuum is that the blood flow to the palm is increased thereby producing 33% greater heat transfer, which is occurring through conduction.
Using Atmospheric Pressure
Palm cooling devices, such as the CoreTx Palm Cooling unit, operate in atmospheric pressure where the palm is cooled through a combination of conduction and convection via a jet of fluid targeting the palm of the hand.
The theory behind operating in atmospheric pressure is that heat transfer may be facilitated through a combination of conduction and convection, which produces greater heat transfer than conduction on its own.
Negative Pressure versus Atmospheric Pressure
Published research comparing the use of mild vacuum and no vacuum when palm cooling provides contrary evidence where moderating core temperature is the objective. One study, by Matthew R Kuennen et al., shows no difference in outcomes between the use of mild vacuum and no vacuum, while another, by Dennis A Grahn et al., showed the use of mild vacuum to be more effective.
Effectiveness
Palm cooling research has expanded beyond managing heat stress to include endurance, strength & conditioning and weight loss.
Endurance
Dr Dennis Grahn et al., of Stanford University conducted research into the impact of palm cooling in aerobic exercise endurance in a hot environment. This study involved applying palm cooling for the duration of the experiment to one hand of the subject while running on a treadmill. It was found that palm cooling extended aerobic exercise work capacity when compared to no cooling.
A study by Andrew R Hsu et al., involving cyclists completing a 30 km time trial concluded that palm cooling for the duration of the trial lowered tympanic (ear) temperature, enabled a higher sustained workload and a faster completion time compared to no cooling.
Strength & Conditioning
Professor Craig Heller et al., conducted studies into the use of palm cooling as an aid to strength & conditioning. Dr Heller reported achieving strength gains on a par with the use of steroids simply by using intermittent palm cooling between training sets with the focus particularly on bench press and pull ups (chin ups). Male subjects achieved 27% greater improvements in work capacity when using palm cooling between sets compared to no cooling.
A study from 2021 by O'brien et al., compared rowing ergometry performance with the use of intermittent palm cooling vs not. This study concluded that lower heart rates and blood lactate concentrations from intermittent cooling caused subjects to experience less fatigue during those workouts and enabled more work to be performed.
A study by Young Sub Kwon et al., consisted of a randomised, double blind, cross over study where subjects used palm cooling (10 °C), palm heating (45 °C) and palm neutral (25 °C) interventions in a bench press study. All subjects used all 3 interventions and were randomly allocated to one of three groups. One group used palm cooling first, another group used palm cooling second and the third group used palm cooling last. For all three groups palm cooling produced on average a 26% increase in work capacity compared to palm neutral. Palm heating produced a 9% increase in work capacity compared to palm neutral.
A similar study was conducted by Young Sub Kwon, et al., where the subjects were all female. In this study the palm cooling produced a 16.8% increase in work capacity and palm heating produced a 13.6% increase in work capacity compared to palm neutral.
A study by J. F. Caruso et al., focused on palm cooling and the leg press exercise, which found clearance of blood lactate and heat removal was greater with intermittent palm cooling. Degradation in average power was also delayed when using palm cooling compared to no cooling.
Weight Loss
A study conducted by Dr Stacy Sims et al., of Stanford University, found the exercise capacity of sedentary obese women was increased with the use of palm cooling. The female subjects using cooling during their exercise sessions lost more weight and improved their exercise capacity compared to the non-cooling control group. Dr Sims said that the drop-out rate was reduced for the cohort of women using cooling.
Heat Stress Management
The initial research focused on mediating core temperature in hypothermic individuals through palm warming and the management of heat stress was investigated using a similar technique i.e. through palm cooling.
Dennis Grahn et al. conducted research at Stanford University and concluded core temperature could be mediated through palm cooling or palm heating when cooling the palm in conjunction with a mild vacuum.
Research conducted by Matthew R Kuennen et al. found palm cooling using the Stanford Glove device was ineffective during simulated armoured vehicle transport.
At the Veterans Affairs Palo Alto Health Care System Andrew R Hsu et al., conducted research into the effect of palm cooling during a cycling exercise in the heat and found no significant impact.
Tessa Maroni at the University of Western Australia lead a research study which compared cooling of one palm with the cooling of two palms. The conclusion was that cooling two palms simultaneously was no more effective than cooling one palm. Both modalities were equally effective in reducing core temperature in hyperthermic individuals as was the use of a cooling jacket.
References
Thermoregulation | Palm cooling | [
"Biology"
] | 2,003 | [
"Thermoregulation",
"Homeostasis"
] |
66,406,720 | https://en.wikipedia.org/wiki/HD%20108236 | HD 108236 is a G-type main-sequence star. Its surface temperature is 5660 K. HD 108236 is severely depleted in heavy elements compared to the Sun, with a metallicity Fe/H index of −0.28 (52% of the Solar System), and is probably older than the Sun at an age of 6.7 billion years.
According to WISE mission data, the star was suspected to be surrounded by a debris disk, but a reanalysis of the data rejected the debris disk hypothesis by 2014. The reason for the false positive was contamination from a nearby infrared source.
Planetary system
In 2020, four planets orbiting HD 108236 were discovered by the transit method, followed by another one in 2021.
See also
List of exoplanets discovered in 2020 - HD 108236 b through e
List of exoplanets discovered in 2021 - HD 108236 f
References
Centaurus
Planetary transit variables
G-type main-sequence stars
Planetary systems with five confirmed planets
J12261789-5121462
CD-50 6971
060689
108236 | HD 108236 | [
"Astronomy"
] | 229 | [
"Centaurus",
"Constellations"
] |
66,407,293 | https://en.wikipedia.org/wiki/K2-66b | K2-66b is a confirmed mega-Earth orbiting the subgiant K2-66, about from Earth in the direction of Aquarius. It is an extremely hot and dense planet heavier than Neptune, but with only about half its radius.
Planet properties
Mass, radius, and temperature
K2-66b is a mega-Earth with radius and mass . The planet's temperature is highly variable due to the variability of its host star, and is currently estimated at .
Orbit
The planet orbits every 5.07 days at 0.06 AU. It orbits within a "photoevaporation desert", where orbiting exoplanets should be very uncommon. K2-66b's orbit is nearly circular.
Star
The star, K2-66 is a G1 sub-giant in Aquarius. It has a sun-like temperature of 5887 K, which corresponds to its spectral class and is very close to that of the rotationally variable star Kepler-130. It has a radius of and a mass of . Its metallicity is −0.047, and its apparent magnitude is 11.71.
See also
Kepler
Mega-Earth
K2-56b
Sub-giant
G-type main sequence star
Density
List of exoplanets discovered in 2017
List of exoplanets discovered in 2016
Lava planet
Stellar evolution
References
External links
Kepler-130
SIMBAD: Kepler-130
Exoplanets discovered in 2017
Mega-Earths
Aquarius (constellation)
Transiting exoplanets
Exoplanets discovered by K2 | K2-66b | [
"Astronomy"
] | 317 | [
"Constellations",
"Aquarius (constellation)"
] |
66,408,231 | https://en.wikipedia.org/wiki/Wilcoxina%20rehmii | Wilcoxina rehmii is an ascomycete fungus of the Peziza group. It was first described in 1985. It has been identified in France, Kyrgyzstan, Canada, and the United States.
References
Pezizaceae
Fungi of Canada
Fungi of the United States
Fungi described in 1985
Fungi without expected TNC conservation status
Fungus species | Wilcoxina rehmii | [
"Biology"
] | 70 | [
"Fungi",
"Fungus species"
] |
66,409,059 | https://en.wikipedia.org/wiki/Xenodens | Xenodens (from Greek and Latin for "strange tooth") is a potentially dubious extinct genus of marine lizard belonging to the mosasaur family. It contains a single species, X. calminechari (From Arabic کالمنشار, meaning "like a saw"), which is known from Late Maastrichtian phosphate deposits in the Ouled Abdoun Basin, Morocco.
Description
Initial estimates suggested the fossil material could belong to an animal with a body length of around . The genus and type species were named for the purported short and flattened blade-like teeth that collectively form a set of saw-like jaws in this taxon. This is a strange feature that had never been seen in any other tetrapod but converge with the jaws of modern dogfish sharks and piranhas. In their 2021 description of this taxon, Longrich et al. hypothesized that these similarities were indicative of a broad diet of cephalopods, crustaceans, fish, and scavenged marine reptiles in Xenodens.
Classification
Xenodens is placed within Mosasaurinae, and its closest known relative is believed to be the durophagous Carinodens. In 2024, Sharpe, Powers & Caldwell reassessed the established holotype of Xenodens and argued that it represents a chimeric forged fossil. Their review suggested that the four teeth preserved in the specimen had been artificially added over two alveoli in the maxilla. The unusual morphology of the preserved teeth may result from intraspecific variation, as tooth shape can vary through ontogeny, so the possibility that the taxon represents an immature Carinodens cannot be precluded. As such, they interpreted the taxon as a nomen dubium in need of more detailed research based on CT scans to determine if the specimen is authentic.
External links
This ancient sea reptile had a slicing bite like no other, Xenodens calminechari, with life-restoration. Science News, February 2, 2021
Xenodens, a weird shark-toothed mosasaur from Morocco- Nick Longrich
References
Mosasaurines
Cretaceous Morocco
Mosasaurs of Africa
Fossil taxa described in 2021
Taxa_named_by_Nicholas_R._Longrich
Nomina dubia | Xenodens | [
"Biology"
] | 477 | [
"Biological hypotheses",
"Nomina dubia",
"Controversial taxa"
] |
66,411,817 | https://en.wikipedia.org/wiki/Thomas%20Ashburton%20Picken | Thomas Ashburton Picken (c. 1818 – 23 January 1891), known professionally as T. Picken, was a Scottish-born watercolourist, engraver and lithographer working in England between around 1834 and 1875. He worked for the printing firm Day and Haghe (later Day & Son) for many years, and first came to notice for his lithograph of The Destruction of Both Houses of Parliament when he was only about 16 years old. Although there is no evidence that he travelled abroad, he produced many lithographs of foreign parts after paintings by other artists. He specialised in detailed images of landscape, architecture, events of war, and ships. He produced lithographs of SS Great Eastern and the laying of the Atlantic cable, and he illustrated books.
Picken's father was the Scots novelist Andrew Picken, and his brother Andrew was a lithographer who also trained with Day and Haghe. Picken ended his days as a Poor Brother at The London Charterhouse, alongside his brother, James Canning (or Channing) Picken. His lithographs are now in many collections, including the Royal Collection Trust, the Library of Congress collection and the Royal Academy collection.
Arts background
Picken's father was Scots writer Andrew Picken (Paisley 1788 – London 23 November 1833), who published various novels including Traditional stories of old families (1833). Thomas' mother was Janet E. Coxon (or Coxson) (1793 – South Stoneham 1871). Andrew Picken senior's first book, Tales and Sketches of the West of Scotland (1824), about historical changes there, "gave great offence to the citizens of Glasgow" and this drove him out of the town. He died in London, where his family were "left in very precarious circumstances" when his son Thomas was around 15 years old. Thomas Picken was one of four sons, three of whom were lithographers. Two of his elder brothers were the lithographer Andrew (1815 – London 24 June 1845) and lithographic artist (later wine merchant) James Canning (or Channing) (Dublin ca.1817 – Brentford 1899). He had two younger sisters: Sophia (b. Glasgow 14 December 1821), and Eleanor Emma (Glasgow ca.1822 – Portsea 21 July 1898) who, as a miniaturist portrait painter, exhibited at the Royal Academy in 1842.
Life
Thomas Ashburton Picken was born around 1818, in Govan, Glasgow. He never married. In 1841 he was living in Great Randolph Street, Kentish Town, London, with his mother Janet, his brother James, and his sisters Emma and Sophia, and describing himself as an artist. In 1851 the census finds him living at 13 Murray Street, Camden, with his brother James and his sister Sophia. By 1861 he was lodging at 27 Rutland Street, St Pancras, London, with the family of sculptor Thomas Woolner (1825–1892). In 1871 he was living as a lodger at 11 Rutland Street, describing himself as a lithographic artist.
Picken and his brother James Canning (or Channing) Picken were accepted as Poor Brothers or male pensioners at the Charterhouse, London. Thomas was described there as a former lithographer and James as a former wine merchant, and Thomas was registered in 1879. On 23 January 1891 he died at the Charterhouse. He was buried on 24 January 1891 with his brother Andrew on the west side of Highgate Cemetery.
Career
Since Thomas Picken was working for Day and Haghe, later Day & Son, in 1834 at the age of around sixteen years, and served the company for the rest of his career, it is likely that he served his apprenticeship there, as did his brother Andrew. He was working as a watercolourist, engraver, lithographer and painter for that company in Camden, London from at least 1834, and flourished until at least 1875.
Probably one of Picken's earliest publications was his lithograph of The Destruction of Both Houses of Parliament, 1834, executed when he was only about 16 years old. No other original artist is credited for this work, so it is not impossible that the initial sketches were undertaken by Picken himself. The authorship of original works on which lithographs were based was usually credited, but such works are often unavailable. Therefore, the question arises as to the extent to which the mid-19th-century lithographers were responsible for the final composition and detail of their engravings. The Day and Haghe lithographer William Simpson said, "In lithography ... we [at times] had to work out rough materials into pictures ... if a man has any stuff in him it finds development."
No evidence of foreign travel has been found, but many of Picken's works after other artists represent locations around the world. He made detailed images of landscape, architecture, events of war, and ships. He illustrated books, and produced lithographs of SS Great Eastern, and the laying of the Atlantic cable.
Selected works
Palace of Westminster: Destruction of both Houses of Parliament, as seen from the Surrey side (1834), by Thomas Ashburton Picken.
Palace of Westminster: Destruction of both Houses of Parliament as seen from Abingdon Street on the Night of October 16th 1834 (1834), by Thomas Ashburton Picken.
King's College Hospital. North or entrance front (ca.1842), after architect Thomas Bellamy (1798–1876).
View of Quebec City, Canada (1845), after the artist and topographical engineer Benjamin Beaufoy (1814–1879).
St Paul's Cathedral (1851), after artist George Sidney Shepherd (ca.1786–1862).
Horse Guards Parade: General view (1851), after George Sidney Shepherd.
Wellington Arch, Hyde Park Corner (1852), after Louis Haghe (1806–1885).
The Great Eastern under weigh July 23rd (circa 1860).
Native Village and Palaver House near Cavalla (1868) after George Townshend Fox (1810–1886).
Some lithographs
Works published as sets
The eight engravings were lithograph copies by Thomas Ashburton Picken of Frances Emilia Crofton's original paintings.
. (This is a bound set of lithographs after Edmund Walker, rather than an illustrated book: Westminster Abbey; General Post Office; Greenwich Hospital; The Treasury Whitehall; The Quadrant Regent Street; St Paul's Cathedral, St Martin's Church; Trafalgar Square; Royal Exchange; Buckingham Palace; London Bridge; British Museum).
Book illustration
(In date order)
(Lithographs after David Roberts).
(Thomas Picken is credited for some of the lithographs).
(At least one lithograph in this book is by Picken after Pyne. Pyne is sometimes listed as "Payne".)
.(Lithographs after William Simpson, Sir William Allan, Clarkson Frederick Stanfield, George Cattermole, William Leighton Leitch, Thomas Creswick, David Roberts, James Duffield Harding, Joseph Nash, Horatio McCulloch, J. M. W. Turner, David Octavius Hill).
(Lithographs after James Baker Pyne).
(Lithograph plate XI after B. Spackman).
(Some of the illustrations are lithographed by Picken).
Exhibitions
Royal Academy of Arts (1857): One watercolour, The Castle Rock, Lynton, North Devon.
Society of Artists of Great Britain (1846–75): ten watercolours.
Collections
Besides the list below, Picken's lithographs are in numerous collections, including: Museum of Science and Industry, Victoria and Albert Museum, Government Art Collection, Library of Congress Collection, Museum of London, National Army Museum, National Library of Poland, National Maritime Museum, London, National Railway Museum, People's Collection, Wales, Royal Academy collection, Royal Museums Greenwich, University of British Columbia, University of Edinburgh collection, Villanova University, Yale Center for British Art, and the British Museum.
Royal Collection Trust: Five of the prints from the Eight Views set (1854), including Killarney, Dunbroody Abbey, Lough Rynn, Muckruss Abbey and Castle Otway after Frances Emilia Crofton, and Launch of the Trafalgar (1842) by T.A. Picken after William Ranwell.
Guildhall Library print room, Wakefield Collection: St Paul's Cathedral (1851).
London Metropolitan Archives and Guildhall Art Gallery: Palace of Westminster: Destruction of both Houses of Parliament, as seen from the Surrey side (1834), Palace of Westminster: Destruction of both Houses of Parliament as seen from Abingdon Street on the Night of 16th October 1834 (1834), Horse Guards Parade: General view (1851), Wellington Arch, Hyde Park Corner (1852),
Wellcome Collection: King's College Hospital. North or entrance front (ca.1842), after Thomas Bellamy, People strolling along Old Well Walk, Cheltenham (1842) by T. Picken after W. Hughes.
National Library of Wales, Welsh Landscape Collection: Various lithographs including Conwy Tubular Bridge (1849) after S. Crowther.
Reviews
Messrs Ackerman of the Strand have just brought out a beautiful lithograph representation of the Launch of the Trafalgar drawn by Mr Ranwell and lithographed by Mr T. Picken. So far as our acquaintance with art goes, this is the first attempt that has been made to do full justice, by pictorial representation, to that soul-stirring scene to every Englishman - a ship launch. The artist could not have made a better selection of subject than the one he has chosen. The launch of the Trafalgar presented, perhaps, the most animating scene of joyousness that ever occurred in this country. More brilliant assemblages take place at Coronations and other great state ceremonies; but the glitter of a pageant has always a certain coldness associated with its formalities. Here, however, was a kind of undress scene of royalty - a monarch brought into immediate contact with her people, and sharing with them in feelings which form their mutual security. Those who were present can never forget the scene - a scene from which, with its multitudinous objects, we should have considered beyond the reach of pictorial art, if we had not seen Mr Ranwell's admirable delineation of the subject. The moment which the artist has perpetuated in the beautiful lithograph before us, is that in which the noble vessel descended majestically into the water, amid the heartwarming huzzas of countless thousands. The situation of the spectator is on the river below the slip - a line of yachts, barges and other craft, with their crowded docks forming the immediate foreground. The figures are admirably disposed and brought up with all the sharpness of a line engraving. - Intermediately is a patch of water with a few light row-boats, and then a line of steamers with their thronged and brilliant assemblages. Next, occupying the centre of the picture, is the noble vessel herself, just settling into the water, a sufficient space being left between her bow and entrance of the dock to discover the Royal party. To describe the various accessory aids which the artist has judiciously drawn into his subject would occupy a page; whilst we only have space left to observe generally that this splendid specimen of lithography is a perfect novelty in art. We had no conception so large a drawing crowded with thousands of figures could be attempted by this process with any chance of success - whilst in distinctness of outline, in sharpness and clearness of body, in delicacy of lights and in fulness of tone his magnificent picture has, as we previously observed, all the power of a line engraving; and as a specimen of lithography stands without a rival. ("Launch of the Trafalgar", Kentish Mercury, 12 March 1842).
Bath from Sham Castle drawn on stone by T. Picken, from a painting by J. Syer. A very beautiful lithograph engraving of the city of Bath has recently been published by Mr Everitt, of the Repository of Arts in that town. The view is taken from Sham Castle, and the town appears unfolded as a map, all the streets and principal buildings being represented with the strictest regard to topographical accuracy. The surrounding country is also seen for many miles, and independently of the value of the engraving in an historical point of view, and as a work of reference, it is commendable for its general fidelity to nature and artistic treatment. ("Bath from Sham Castle", Morning Post, 28 September 1850).
Further research
Notes
References
External links
1818 births
1891 deaths
Burials at Highgate Cemetery
English lithographers
Draughtsmen
English illustrators
English watercolourists
Scottish lithographers
Scottish illustrators
Scottish watercolourists | Thomas Ashburton Picken | [
"Engineering"
] | 2,702 | [
"Design engineering",
"Draughtsmen"
] |
66,412,064 | https://en.wikipedia.org/wiki/Depleted%20uranium%20hexafluoride | Depleted uranium hexafluoride (DUHF; also referred to as depleted uranium tails, depleted uranium tailings or DUF6) is a byproduct of the processing of uranium hexafluoride into enriched uranium. It is one of the chemical forms of depleted uranium (up to 73-75%), along with depleted triuranium octoxide (up to 25%) and depleted uranium metal (up to 2%). DUHF is 1.7 times less radioactive than uranium hexafluoride and natural uranium.
History
The concept of depleted and enriched uranium emerged nearly 150 years after the discovery of uranium by Martin Klaproth in 1789. In 1938, two German physicists Otto Hahn and Fritz Strassmann had made the discovery of the fission of the atomic nucleus of the 235U isotope, which was theoretically substantiated by Lise Meitner, Otto Robert Frisch and in parallel with them Gottfried von Droste and Siegfried Flügge. This discovery marked the beginning of the peaceful and military use of the nuclear energy of uranium. A year later, Yulii Khariton and Yakov Zeldovich were the first to prove theoretically that with an enrichment of 235U in natural uranium, a chain reaction could be sustained. This nuclear chain reaction requires on average that at least one neutron, released by the fission of an atom of 235U, will be captured by another atom of 235U and will cause it also to fission. The probability of a neutron being captured by a fissile nucleus should be high enough to sustain the reaction. To increase this probability, an increase in the proportion of 235U is necessary, which in natural uranium constitutes only 0.72%, along with 99.27% 238U and 0.0055% 234U.
Competition
By the mid-1960s, the United States had a monopoly on the supply of uranium fuel for Western nuclear power plants. In 1968, the USSR declared its readiness to accept orders for uranium enrichment. As a result, a competitive market formed in the world, and commercial enrichment companies began to appear (e.g., URENCO and Eurodif). In 1971, the first Soviet contract was signed with the French Alternative Energies and Atomic Energy Commission, where nuclear power plants were actively built. In 1973, roughly 10 long-term contracts were signed with power companies from Italy, Germany, Great Britain, Spain, Sweden, Finland, Belgium and Switzerland. By 2017, large commercial enrichment plants have been operating in France, Germany, the Netherlands, Great Britain, the United States, Russia and China. The development of the enrichment market has led to the accumulation of over 2 million tons of DUHF in the world during this period.
Other forms of depleted uranium
Depleted uranium may exist in several chemical forms; in the form of DUHF, the most common form, with a density of 5.09 g/cm3, in the form of depleted triuranium octoxide (U3O8) with a density of 8.38 g/cm3, and in the form of depleted uranium metal with a density of 19.01 g/cm3.
Physical properties
Since the various uranium isotopes share the same chemical properties, the chemical and physical properties of depleted, enriched, and unenriched UF6 are identical, except for the degree of radioactivity. Like other forms of UF6, under standard conditions, DUHF forms white crystals, with a density of 5.09 g/cm3. At pressures below 1.5 atm, the solid DUHF sublimes into gas when heated, with no liquid form. At 1 atm, the sublimation point is 56.5 °C. The critical temperature of DUHF is 230.2 °C, and the critical pressure is 4.61 MPa.
Radioactivity
The radioactivity of DUHF is determined by the isotopic composition of uranium because the fluorine in the compound is stable. The radioactive decay rate of natural UF6 (with 0.72% 235U) is 1.7×104 Bq/g of which 97.6% is due to 238U and 234U.
When uranium is enriched, the content of light isotopes, 234U and 235U, increases. Although 234U, despite its much lower mass fraction, contributes more to the activity, the target isotope for nuclear industry use is 235U. Therefore, the degree of uranium enrichment or depletion is specified by the content of 235U. The reduction of 234U, and to a slight degree 235U, content reduces the radioactivity below unenriched UF6.
Production
Low enriched uranium with enrichment of 2 to 5% 235U (with some exceptions when using 0.72% in natural composition, for example in Canadian CANDU reactors) is used for nuclear power, in contrast to weapons-grade highly enriched uranium with 235U content of over 20% and usually over 90%. Various methods of isotope separation are used to produce enriched uranium, mainly gas centrifugation and, in the past, the gaseous diffusion method. Most of them work with gaseous UF6, which in turn is produced by fluorination of elemental uranium tetrafluoride (UF4 + F2 → UF6) or uranium oxides (UO2F2 + 2 F2 → UF6 + O2), both highly exothermic.
Since UF6 is the only uranium compound that is gaseous at a relatively low temperature, it plays a key role in the nuclear fuel cycle as a substance suitable for separating 235U and 238U. After obtaining enriched UF6, the remainder (approximately 95% of the total mass) is transformed into depleted UF6 , which consists mainly of 238U, because its 235U content is reduced by perhaps a factor of three, and its 234U content by a factor of six (depending on the degree of depletion). In 2020, nearly two million tons of depleted uranium was accumulated in the world. Most of it is stored in the form of DUHF in special steel tanks.
The methods of handling depleted uranium in different countries depends on their nuclear fuel cycle strategy. The International Atomic Energy Agency (IAEA) recognizes that policy determination is the prerogative of the government (para. VII of the Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management). Given the technological capabilities and concepts of the nuclear fuel cycle in each country, with access to separation facilities, DUHF may be considered as a valuable raw material on one hand or low-level radioactive waste on the other. Therefore, there is no unified legal and regulatory status for DUHF in the world. The IAEA expert report , 2001 and the joint report of the OECD, NEA and IAEA Management of Depleted Uranium, 2001 recognize DUHF as a valuable raw material.
Applications
As a result of chemical conversion of DUHF, anhydrous hydrogen fluoride and/or its aqueous solution (i.e. hydrofluoric acid) are obtained, which have a certain demand in non-nuclear energy markets, such as the aluminum industry, in production of refrigerants, herbicides, pharmaceuticals, high-octane gasoline, plastics, etc. It is also applied in the reuse of hydrogen fluoride in the production of UF6 via the conversion of U3O8 into uranium tetrafluoride (UF4), before further fluorination into UF6.
Processing
There are multiple directions in the world practice of DUHF reprocessing. Some of them have been tested in a semi-industrial setting, while others have been and are being operated on an industrial scale with an effort to reduce the reserves of uranium tailings and provide the chemical industry with hydrofluoric acid and industrial organofluorine products.
Depending on nuclear fuel cycle strategy, technological capabilities, international conventions and programs, such as the Sustainable Development Goals (SDG) and the UN Global Compact, each country approaches the issue of the use of accumulated depleted uranium individually. The United States has adopted a number of long-term programs for the safe storage and reprocessing of DUHF stocks prior to their final disposal.
Sustainable development goals
Under the UN SDG, nuclear power plays a significant role not only in providing access to affordable, reliable, sustainable and modern energy (Goal 7), but also in contributing to other goals, including supporting poverty, hunger and water scarcity elimination, economic growth and industry innovation. Several countries, such as the United States, France, Russia, and China, through their leading nuclear power operators, have committed to achieving the Sustainable Development Goals. To achieve these goals, various technologies are being applied both in the reprocessing of spent fuel and in the reprocessing of accumulated DUHF.
Transportation
International policies for transporting radioactive materials are regulated by the IAEA since 1961. These regulations are implemented in the policies of the International Civil Aviation Organization, International Maritime Organization, and regional transport organizations.
Depleted UF6 is transported and stored under standard conditions in solid form and in sealed metal containers with wall thickness of about 1 cm (0.39 in), designed for extreme mechanical and corrosive impacts. For example, the most common "48Y" containers for transportation and storage contain up to 12.5 tons of DUHF in solid form. DUHF is loaded and unloaded from these containers under factory conditions when heated, in liquid form and via special autoclaves.
Dangers
Due to its low radioactivity, the main health hazards of DUHF are connected to its chemical effects on bodily functions. Chemical exposure is a major hazard at facilities associated with the processing of DUHF. Uranium and fluoride compounds such as hydrogen fluoride (HF) are toxic at low levels of chemical exposure. When DUHF comes in contact with air moisture, it reacts to form HF and gaseous uranyl fluoride. HF is a corrosive acid that can be extremely dangerous if inhaled; it is one of the major work hazards in such industries.
In many countries, current occupational exposure limits for soluble uranium compounds are related to a maximum concentration of 3 μg of uranium per gram of kidney tissue. Any effects caused by exposure to these levels on the kidneys are considered minor and temporary. Current practices based on these limits provide adequate protection for workers in the uranium industry. To ensure that these kidney concentrations are not exceeded, legislation limits long-term (8 hours) concentrations of soluble uranium in workplace air to 0.2 mg per cubic meter and short-term (15 minutes) to 0.6 mg per cubic meter
Incidents during transportation
In August 1984, the freighter MS Mont Louis sank in the English Channel with 18 containers of slightly depleted (0.67% 238U) uranium hexafluoride on board, along with enriched and natural UF6. The 30 containers (type 48Y) of UF6 were recovered, as well as 16 of the 22 empty containers (type 30B). Examination of the 30 containers revealed, in one case, a small leak in the shutoff valve. There were 217 samples taken, subjected to 752 different analyses and 146 measurements of dose levels on the containers. There was no evidence of leakage of either radioactive (natural or recycled uranium) or hazardous chemical substances (fluorine or hydrofluoric acid). According to The Washington Post, this incident was not hazardous because the uranium cargo was in its natural state, with an isotope 235U content of 0.72% or less, and only some of it was enriched to 0.9%.
See also
Traveling wave reactor - a reactor concept that uses depleted uranium for fuel
Notes
References
Element toxicology
Uranium, Depleted
Uranium | Depleted uranium hexafluoride | [
"Physics",
"Chemistry"
] | 2,441 | [
"Element toxicology",
"Biology and pharmacology of chemical elements",
"Materials",
"Nuclear materials",
"Matter"
] |
66,412,668 | https://en.wikipedia.org/wiki/NE5532 | The NE5532, also sold as SA5532, SE5532 and NG5532 (commonly called just 5532) is a dual monolithic, bipolar, internally compensated operational amplifier (op amp) for audio applications introduced by Signetics in 1979. The 5532 and the contemporary TL072 were the first operational amplifiers that outperformed discrete class A circuits in professional audio applications. Due to low noise and very low distortion, the 5532 became the industry standard for professional audio. According to Douglas Self, "there is probably no music on the planet that has not passed through a hundred or more 5532s on its way to the consumer". The performance of the 5532 remained best in class for almost thirty years, until the introduction of the LM4562 in 2007. As of 2021, the 5532 remains in mass production as a generic product.
Unlike many other low-cost op amps, the 5532 exists only in a dual form, available in 8-pin PDIP, SO and SOIC packages. The single 5534, as well as the discontinued uncompensated dual 5533, is not fully compensated and is thus unstable at unity gain; the 5534 has lower noise density than the 5532 but is otherwise similar.
History
The op-amp was originally made by Signetics and sold by Philips Semiconductors as TDA1034 and later renamed.
Construction and operation
The 5532 is fully bipolar, with the exception of a sole JFET within a bias generator. Although the manufacturers did not release a first-hand explanation of its operation, the schematic has been public for decades. The signal path consists of two consecutive differential stages, a single-ended common emitter voltage amplification stage, and a class B push-pull output follower with a current-sensing overload protection. There are four internal compensation capacitors. The distortion "signature" (that is, the virtual absence of it) of the 5532 is defined largely by the three nested frequency compensation loops wrapped around the second and the third stages.
Input requirements
The input stage uses NPN transistors, thus the input bias currents flow into their bases, and cause negative voltage drop across the ground-to-input resistance. A typical 200nA bias current flowing through a typical 47kOhm resistor, for example, will cause a 10 mV voltage drop. These fairly stable shifts in operating points are usually not a concern. If possible, audio designers would allow them to accumulate over several stages, and then block the accumulated DC offset with a single output capacitor. Bias currents may not be allowed to flow through potentiometers, as it causes excessive crackling noise when the wipers are moved.
The inputs of the 5532 are protected with back-to-back diodes rated for currents up to 10 mA; these may open during fast input signal transients, and cause harsh output distortion. The 5532 is intended for linear operation only, and should not be used as a comparator, or otherwise subjected to large differential input voltages.
A typical 5532 operating from ±15 V supply rails retains linearity as long as the input voltages remains within ±13 V range. When common-mode voltage exceeds +13 V or goes below -13 V, the 5532 clips but remains operational as long as either input stays within the power supply voltages. Input overdrive does not cause output phase inversion which is common to the TL072 op amp.
Power supply requirements
The 5532 stands out among audio op amps in having an unusually high absolute maximum supply voltage rating of 44 V (compared to more common 36 V). In practice, each of the two amplifiers draws a fairly high 45 mA supply current, and the plastic package becomes appreciably warm at 34 V supply voltage. According to Douglas Self, using power supplies of more than 34 V is potentially unsafe, and certainly incompatible with most other op amps.
The 5532 is sensitive to power supply AC decoupling; failure to decouple leads to erratic internal high-frequency oscillation that does not propagate to the output directly, but causes apparent distortion. A single 0.1 μF high-quality capacitor, connected across the power supply pins and in close proximity to them, is normally sufficient to prevent such oscillations. The manufacturers recommend using two such capacitors, connected between each power supply pin and the ground; according to Douglas Self, this is not necessary and sometimes undesirable due to the risks of injecting noise currents into the signal ground.
Distortion
The 5532 attains lowest total harmonic distortion (THD) in an inverting (shunt-feedback) configuration with moderate gain and moderate signal levels, where the THD does not exceed 0.0005% throughout the audio frequency spectrum. High source impedances inject added thermal noise, but do not affect the THD of the inverting amplifier. Increasing output level to 10V does not affect performance through most of the audio frequency, except for the octave above 10kHz where the THD rises to 0.001%. For comparison, the classic μA741 can deliver the rated 0.001% THD only at frequencies below 100Hz; above the100 Hz mark the THD continuously increases, reaching 1% at around 20kHz.
In the non-inverting (series-feedback) configuration driven with a low-impedance source the 5532 demonstrates mild common-mode distortion. This form of distortion is most prominent at unity gain, but even there THD remains under 0.002% as long as the source impedance does not exceed 2 kOhm. The reported "sweet spot" lies around 1 kOhm source impedance, although this may be dependent on the manufacturer. As source impedances increase to 10 kOhm and beyond, 5532 performance radically worsens. Distortion is now dominated by components that are proportional to the square of common-mode signal voltage. Worst-case THD may exceed 0.02% at the treble end of the audio range.
Noise
The 5532, like all bipolar-input op amps, has significant current and voltage noise densities, typically 5nV/Hz1/2 and 0.7pA/Hz1/2, respectively, at 1kHz. Even accounting for the increase in noise densities at lower frequencies, voltage noise and current noise over the 20kHz audio bandwidth do not exceed 1μV and 100pA, respectively. The three noise components differential voltage noise referred to inputs, inverting input current and non-inverting input current are assumed to be uncorrelated with each other. In reality there is some correlation, but its effect is insignificant.
Current and noise densities of the far more expensive bipolar-input OP27 and OP270, as well as the 5534, are only about 23 dB lower. The LM4562 has half the voltage noise of the 5532, but more than twice current noise. FET input devices have much higher voltage noise densities but practically nonexistent current noise The extremely low-noise LT1028 is nominally 15dB quieter than the 5532, but is otherwise poorly suited for audio applications. The choice of the "lowest noise op amp" ultimately depends on which form of noise, voltage noise or current noise, is most critical in a specific application.
NE5534
The 5534 single operational amplifier is schematically identical to one half the 5532, with marginally different values of the internal compensation capacitors. The difference, however, is large enough to decompensate the amplifier. The 5534 is stable only at closed-loop gain of 3 and more. The slew rate is accordingly higher, typically 13V/μs compared to 9V/μs of the 5532; the unity gain crossover frequency is also higher, at around 3050 MHz. The unity gain bandwidth of 10MHz, same as for the 5532, is quoted for a fully compensated amplifier (implying the use of an external compensation capacitor). The input-referred noise densities are marginally lower. In practical applications, particularly large professional audio consoles, these advantages were not as important as was the added complexity, so the single 5534 did not see as much use as the dual 5532. The third IC in the family, the dual uncompensated 5533, has been long discontinued.
For unity-gain stability, the 5534 requires an external compensation capacitor of at least 22pF for the non-inverting circuit, and 11pF or more for the inverting circuit. Compensation inevitably decreases slew rate, compromising response to fast signal transients. This is unimportant in audio equipment, where the worst-case, theoretical slew rate at maximum output swing barely exceeds 2V/μs. In more demanding applications, stability and high slew rate may be maintained simultaneously with the help of a lead-lag RC network between the 5534 inputs. The corner frequency of lead-lag network is normally selected at around 35 MHz, one decade below the unity gain crossover frequency. The regular compensation capacitor must remain, but its value can be safely decreased to 3pF at unity gain.
Notes
References
Electronic amplifiers
Linear integrated circuits | NE5532 | [
"Technology"
] | 1,923 | [
"Electronic amplifiers",
"Amplifiers"
] |
66,413,347 | https://en.wikipedia.org/wiki/PSR%20J1544%2B4937 | PSR J1544+4937 is a pulsar and gamma-ray source. It is a millisecond pulsar with a very short rotation period of 2.16 milliseconds. Additionally, it has a planet or brown dwarf known as PSR J1544+4937 b.
See also
Black Widow Pulsar
References
Pulsars
Boötes | PSR J1544+4937 | [
"Astronomy"
] | 80 | [
"Boötes",
"Constellations"
] |
66,414,069 | https://en.wikipedia.org/wiki/Beno%C3%AEt%20Godin | Benoît Godin was a Canadian political scientist and sociologist.
Biography
Benoît Godin is mostly known for his research into the history of statistics, statistics of innovation, and of the ideological roots of the concept of innovation. After a first degree at the Université Laval (1984) in Québec (CA), he obtained a PhD at the Science Policy Research Unit (SPRU) the University of Sussex (UK) in 1994). From February 1993 until his death he was professor at Institut national de la recherche scientifique INRS, Québec (CA).
Work
The work of Benoît Godin covers both the history of quantification and that of innovation. He worked on measurement statistics in science, on the history of science proper, as well as that of technology and innovation. In the last years of his life he focused on the intellectual history of innovation, noting how the ‘superlative’ connotation of the term innovation is recent, in relative terms, as it had a rather negative connotation until the late 1960s or early 1970s.
Books
(As editor with Dominique Vinck) Critical Studies of Innovation: Alternative Approaches to the Pro-Innovation Bias.
See also
Innovation
Science and technology studies
Social construction of technology
References
External links
Page of Benoît Godin at INRS
Page of The Idea of Innovation, A project funded by the Canadian Social Sciences and Humanities Research Council (SSHRC).
CASTI Network, Conceptual Approaches to Science, Technology, and Innovation: An Interdisciplinary Research Network.
Sociologists of science
Science studies
Science and technology studies scholars
Social constructionism
Sociology of scientific knowledge
21st-century Canadian philosophers
Canadian philosophers of science
Philosophers of technology
1958 births
2021 deaths | Benoît Godin | [
"Technology"
] | 336 | [
"Science and technology studies",
"Science and technology studies scholars"
] |
66,414,967 | https://en.wikipedia.org/wiki/Mentophobia | Mentophobia or mentaphobia is a concept described by Donald Griffin, an American zoologist and the founder of cognitive ethology, to denote strong resistance from scientists to the idea that animals, other than humans, are conscious. Griffin argued that there is a taboo "against scientific consideration of private, conscious, mental experiences" that leads to the minimization of the significance of the consciousness of non-human animals, as well as human consciousness and asserted that this presents a significant barrier to scientific progress.
Mentophobia has been likened to Frans de Waal's concept of anthropodenial: "a blindness to the humanlike characteristics of other animals, or the animal-like characteristics of ourselves". It has also been compared with an observation by Daniel Dennett that "a curious asymmetry can be observed" when it comes to the certainty of human consciousness not being required for moral certainty, but moral certainty is not applied when it comes to the experiences of other animals.
David Chauvet in Contre la Mentaphobie ("Against Mentaphobia"), argues that the denial of the consciousness of animals alleviates the guilt that is associated with abuses directed towards them.
References
Further reading
Animal cognition
Animal ethics
Consciousness | Mentophobia | [
"Biology"
] | 258 | [
"Animals",
"Animal cognition"
] |
66,415,993 | https://en.wikipedia.org/wiki/Erwin%20Stolz | Erwin Stolz (1896 Giesshuebel/Sauerbrunn - 1987 Vienna) was a Czech painter and draughtsman.
Biography
After an experience as agricultural engineer and captivity in Italy during the World War I, he devoted himself to painting, working as a sign painter, industrial graphic artist and attending numerous art courses in Vienna. He had contacts to (1902–1983) who had an influence in the Viennese world in the spread of the avant-gardes, Erich Mallina (1873–1954) who introduced him in his mystical-religious worldview and in the theosophical society, George Kenner (1888–1971) who shared his experience in prison camps during the First World War, (1870–1946) who was a great illustrator and symbolist painter as Stolz himself and the artists of union Hagenbund. He was also a friend of Josef Matthias Hauer (1883–1959) a composer and music theorist near to Arnold Schoenberg whose art was considered degenerate art by nazism.
In his career Stolz followed various artistic currents. He had a classical training which was admirably expressed in portraits, in liberty paintings (nouveau and deco in particular) and in symbolism that distinguishes many of his drawings and temperas in which he expressed an art of great graphic quality highly influenced by Max Klinger (1857 - 1920) and Gust Klimt (1862 - 1918). In the 20s, however, alongside these trends he also became interested in expressionist painting and in the New Objectivity as can be appreciated in some portraits and in the numerous nudes made from 1925 to the end of the 30s which was his most fruitful period. After the World War II his painting was oriented above all in a surrealist key.
Artworks
Erwin Stolz excelled above all in ink drawing where in the 30s and 40s he touched absolute peaks not only of great formal and technical refinement but also of great creativity, succeeding in the not easy intent of rendering through the lines depth, atmospheric sense, tonalism in the absence of color or better with a single color, black, with which he was able to create not only the entire chromatic range but also to render the objective reality of what he represented.
Works
"Fighting Knights", oil on canvas, Signed with monogram, Galleria d'arte moderna Aroldo Bonzagni
"Mother and child eating grapes", Gouache and watercolor. Signed with monogram.
"Temptation", Tempera on paper. Signed with monogram
"After the fall - Eve and Adam", Gouache and tempera.Signed with monogram
"Mother and child in an enchanted winter landscape", Tempera on Cardboard. Signed with monogram
"Doge und Dogaresse", Tempera. Signed with monogram
"Im Garten Eden", Oil on Board. Signed with monogram.
"Emergence of spring", Tempera on paper laid on cotton. Signed with monogram.
"Lovers" Watercolor and gouache.Signed with monogram.
"Andante mysterioso", coloured pencils on paper, Signed with monogram, c. 1920, The Jack Daulton Collection, Los Altos Hills
"Magical Landscape", pen and ink on paper, Signed with monogram, c. 1920, The Jack Daulton Collection, Los Altos Hills
"Eve", Oil on paper (framed),Initialed and dated 1920, The Adriana Williams Collection, USA.
"Destiny", pen and black ink, signed with monogram, 1924
"Celestial figures", pen and black ink, with monogram,
"Tragedy", pen and black ink, with monogram,
"The bathers", pen and black ink, signed with monogram,1926
"The life of Jesus", pen and black ink, signed with monogram,1937
"Peasants at work", pen and black ink, signed with monogram,1938
"The holy family", pen and black ink, signed with monogram, c. 1925
References
1896 births
1987 deaths
20th-century Czech painters
20th-century Czech male artists
Symbolist painters
Art Nouveau painters
Draughtsmen
Painters from Vienna | Erwin Stolz | [
"Engineering"
] | 859 | [
"Design engineering",
"Draughtsmen"
] |
66,416,216 | https://en.wikipedia.org/wiki/%C3%89va%20Kondorosi | Éva Kondorosi, (born 1948) is a Hungarian-French biochemist who is known for her work on Rhizobium-legume symbiosis. She has been a member of the National Academy of Sciences since 2010. In 2015 she became a member of the German Academy of Sciences Leopoldina, and in 2020 she was appointed as a Chief Scientific Advisor to the European Commission.
Biography
Education
Éva Kondorosi was born in 1948 in Budapest, Hungary. She studied biology at the Faculty of Sciences in Budapest and later she earned a doctorate in genetics at the Loránd Eötvös University in Budapest.
Career
In 1973, Kondorosi joined the Biology Research Centre of the Hungarian Academy of Sciences in Szeged. As a young researcher, she continued her training and completed several internships abroad at: University of Sussex in the United Kingdom, Harvard and Cornell Universities in the United States, and the Max-Planck Society in Germany between 1973 and 1986. In 1989, she settled in France and joined the National Centre for Scientific Research (CNRS) as a research director at the Institute of Plant Sciences in Gif-sur-Yvette. Since March 2013, she has been emeritus research director of the CNRS. She obtained French nationality in 1995.
She has played a leading role in scientific collaboration between France and Hungary.
Throughout her career in France, she maintained close ties with her home institution, the Szeged laboratory. This allowed for collaboration between the Gif-sur-Yvette laboratory and the Szeged laboratory. As a result, the two institutions were twinned through the creation of the BAYGEN Institute (2007–2012), which is now an integral part of the Biology Research Center of the Hungarian Academy of Sciences in Szeged.
Currently, she works at the Biology Research Center of the Hungarian Academy of Sciences in Szeged and heads the Symbiosis Laboratory and the Functional Genomics Unit.
Kondorosi is a member and corresponding member of several academies, including the National Academy of Sciences in the United States and the Academia Europaea. She is a member of the Scientific Council, the European Research Council, and the European Molecular Biology Organization. She serves on the board of the International Society for Plant-Microbe Molecular Interactions (IS-MPMI). She helped launch UNESCO's Women in Science program and was a member of the international jury for the L'Oréal-Unesco For Women in Science Award.
Research
Kondorosi is recognized for her work in the study of Rhizobium - legume symbiosis, in particular for the discovery and characterization of a series of cysteine-rich nodule peptides that are important signaling molecules. Her research findings on cell cycle regulation during symbiosis, on the differentiation of Bacteroides, and on the production of peptides with antimicrobial activity have earned her international recognition. The plant responds to the presence of Rhizobium by creating nodules on the roots, in which the bacteria grow. The bacteria in the nodules are able to transform nitrogen from the air into a form that can be used by the plant, thus providing an essential nutrient, often scarce in the environment. Beyond the importance of its contribution to basic science, a better understanding of nitrogen fixation is crucial for food security and for reducing society's dependence on fertilizers, which are energy-intensive and whose production is a major source of greenhouse gases.
His current research focuses on the dual use of strategies used naturally by plants in agriculture and public health.
Personal life
Andor Tarnai, the late father of Éva Kondorosi, was a Hungarian writer and a literary historian. She was married to Ádám Kondorosi, a Hungarian biologist.
Distinctions and awards
2022: Best Molecular Biology Scientists, Research.com
2019: Prix de la Ville de Szeged
2018: Balzan Prize for Chemical Ecology
2017: Grand prix de la Fondation Szeged
2012: Hungarian Széchenyi Prize for outstanding scientific contribution
2012: International Society for Plant-Microbe Molecular Interactions (IS-MPMI) Award
2011: Prix de Szeged
2011: Biology Research Prize
2007: Hotchkiss Award
1985: Prize of the Hungarian Academy of Sciences
References
External links
Hungarian women scientists
French women scientists
Hungarian biochemists
French biochemists
Women biochemists
Living people
Members of the German National Academy of Sciences Leopoldina
1948 births | Éva Kondorosi | [
"Chemistry"
] | 906 | [
"Biochemists",
"Women biochemists"
] |
66,417,592 | https://en.wikipedia.org/wiki/Sodium%20nitrite/sodium%20thiosulfate | Sodium nitrite/sodium thiosulfate, sold under the brand name Nithiodote, is a fixed-dose combination medication used as an antidote for cyanide poisoning. It contains sodium thiosulfate and sodium nitrite. It is given by intravenous infusion into a vein.
It was approved for medical use in the United States in January 2011.
Medical uses
Sodium nitrite/sodium thiosulfate is indicated for the treatment of acute cyanide poisoning.
See also
Sodium nitrite
Sodium thiosulfate
References
External links
Combination drugs | Sodium nitrite/sodium thiosulfate | [
"Chemistry"
] | 121 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
66,418,511 | https://en.wikipedia.org/wiki/SM-102 | SM-102 is a synthetic amino lipid which is used in combination with other lipids to form lipid nanoparticles. These are used for the delivery of mRNA-based vaccines, and in particular SM-102 forms part of the drug delivery system for the Moderna COVID-19 vaccine.
Lipid nanoparticles are an extension of earlier RNA transfection methods such as cationic liposomes. Such systems are needed to protect the delicate mRNA molecules and shuttle them into cells without the immune system destroying them first. The nanoparticles enter the cells by triggering receptor-mediated endocytosis.
Ionisable lipids like SM-102 hold a relatively (/ close to) neutral charge at physiological pH but are positively charged within the nanoparticle (the amine group is protonated to form an ammonium cation). This allows them to bind to the negatively charged backbone of mRNA. The rest of the nanoparticle is formed from PEGylated lipids, which help stabilize the particle, and phospholipids and cholesterol molecules that contribute to the particle’s structure.
SM-102 is also used for non-invasive bioluminescence imaging when SM-102 containing luciferase-encoding mRNA is used for in-vivo luciferase expression in animal models.
Synthesis
The preparation of SM-102 was first described in a patent application to lipid nanoparticles by Moderna in 2017. The final step is an alkylation reaction in which a secondary amine is combined with a lipid bromo ester.
HO(CH2)2NH(CH2)7CO2CH(C8H17)2 + Br(CH2)5CO2C11H23 → SM-102
See also
ALC-0315
Moderna COVID-19 vaccine nanoparticle ingredients
Distearoylphosphatidylcholine
DMG-PEG 2000
References
Tertiary amines
Lipids
Ethanolamines
Esters | SM-102 | [
"Chemistry"
] | 413 | [
"Biomolecules by chemical classification",
"Esters",
"Functional groups",
"Organic compounds",
"Lipids"
] |
61,428,301 | https://en.wikipedia.org/wiki/HIP%2065426%20b | HIP 65426 b, formally named Najsakopajk, is a super-Jupiter exoplanet orbiting the star HIP 65426. It was discovered on 6 July 2017 by the SPHERE consortium using the Spectro-Polarimetric High-Contrast Exoplanet Research (SPHERE) instrument belonging to the European Southern Observatory (ESO), being the first planet discovered by the SPHERE instrument. It is 385 light-years from Earth in the Centaurus constellation.
Nomenclature
HIP 65426 b is a designation inherited from the host star's name, HIP 65426, following the exoplanet naming convention, where exoplanets receive lowercase letters. The designation HIP 65426 has its origin on the Hipparcos catalogue.
In August 2022, this planet and its host star were included among 20 systems to be named by the third NameExoWorlds project. The approved names, proposed by a team from Mexico, were announced in June 2023. HIP 65426 b is named Najsakopajk and its host star is named Matza, after Zoque words for "Mother Earth" and "star".
Overview
The exoplanet HIP 65426 b orbits its host star HIP 65426, an A-type main-sequence star with apparent magnitude 7.01, with a mass of , a radius of and an effective temperature of . This planetary system is located in the constellation Centaurus. The planet is around 14 million years old, much younger than the Solar System which is 4.5 billion years old, but is not associated with a debris disk, despite its young age, causing it to not fit current models for planetary formation. It is around 92 AU from its parent star, with a possible dusty atmosphere. It was discovered as part of the SHINE program, which aimed to find planetary systems around 600 new stars.
In September 2022, HIP 65426 b became the first exoplanet directly observed by the James Webb Space Telescope.
Planetary atmosphere
The spectrum taken in 2020 has indicated that HIP 65426 b is carbon-poor and oxygen-rich compared to Solar System gas giants.
Spectral analysis of data from the James Webb Space Telescope revealed strong evidence of silicate clouds containing enstatite with no evidence of a dusty atmosphere.
James Webb Space Telescope observations
In August 2022, a pre-print of the James Webb Space Telescope (JWST) observations was published. The JWST direct imaging observations between 2-16 μm of HIP 65426 b tightly constrained its bolometric luminosity to , which provides a robust mass constraint of . Evolutionary models suggest a radius 45% larger than that of Jupiter and an effective temperature of . Atmospheric models suggest lower radii down to and higher temperatures, but these results are unreliable. The team also constrained the semi-major axis and the inclination of the planet, but the new JWST astrometry of the planet did not significantly improve the orbit of the planet, especially the eccentricity remains unconstrained.
HIP 65426 b is the first exoplanet to be imaged by JWST and the first to be detected in wavelengths beyond 5 μm. The observations demonstrate that the James Webb Space Telescope will exceed its nominal predicted performance by a factor of 10 and that it will be able to image 0.3 planets at 100 au for main-sequence stars, Neptune and Uranus-mass objects at 100-200 au for M-dwarfs and Saturn-mass objects at 10 au for M-dwarfs. For α Cen A JWST might be able to push the limit to a 5 planet at 0.5 to 2.5 au.
See also
Lists of exoplanets
List of exoplanets discovered in 2017
References
Exoplanets detected by direct imaging
Exoplanets discovered in 2017
Giant planets
Centaurus
Exoplanets with proper names | HIP 65426 b | [
"Astronomy"
] | 801 | [
"Centaurus",
"Constellations"
] |
61,428,306 | https://en.wikipedia.org/wiki/Journal%20of%20Gene%20Medicine | The Journal of Gene Medicine is a monthly peer-reviewed medical journal covering gene therapy and other uses of genetic technologies for medical purposes. It was established in 1999 and is published by John Wiley & Sons. The editors-in-chief is Gening Jiang (Tongji University). According to the Journal Citation Reports, the journal has a 2020 impact factor of 4.565, ranking it 43rd out of 160 journals in the category "Biotechnology & Applied Microbiology".
References
External links
Gene therapy
Medical genetics journals
English-language journals
Wiley (publisher) academic journals
Monthly journals
Academic journals established in 1999
Biotechnology journals | Journal of Gene Medicine | [
"Engineering",
"Biology"
] | 123 | [
"Biotechnology literature",
"Gene therapy",
"Genetic engineering",
"Biotechnology journals"
] |
61,428,542 | https://en.wikipedia.org/wiki/XPoSat | The X-ray Polarimeter Satellite (XPoSat) is an Indian Space Research Organisation (ISRO)-manufactured space observatory to study polarisation of cosmic X-rays. It was launched on 1 January 2024 on a PSLV rocket, and it has an expected operational lifespan of at least five years.
The telescope was developed by the Raman Research Institute (RRI) in close collaboration with U R Rao Satellite Centre (URSC). Per ISRO, this mission will complement the efforts of US space agency NASA, which launched its Imaging X-ray Polarimetry Explorer (IXPE) in 2021 by observing space events across a broad energy range of 2–30 keV.
Overview
Studying how radiation is polarised gives away the nature of its source, including the strength and distribution of its magnetic fields and the nature of other radiation around it. XPoSat will study the 50 locally brightest (known) sources in the universe consisting of, variously, pulsars, black hole X-ray binaries, active galactic nuclei, neutron stars and non-thermal supernova remnants. The observatory was placed in a circular low Earth orbit of . The payloads onboard XPoSat will observe the X-Ray sources during its transit through the Earth's eclipse period.
History
The XPoSat project began in September 2017 with Indian Space Research Organisation (ISRO) grant of . Preliminary Design Review (PDR) of the XPoSat including the POLIX payload was completed in September 2018, followed by preparation of POLIX Qualification Model and beginning of some of its Flight Model components fabrication.
Launch
XPoSAT was successfully launched aboard PSLV-C58 on 1 January 2024 at 9:10 am IST. The launch was precise, leaving only a deviation of (±) 3 km. Following the launch, the final 4th stage of the PSLV dropped to a 350 x 350 km orbit to facilitate its use as PSLV Orbital Experimental Module POEM-3.
First Light
XSPECT
The XSPECT payload on XPoSat captured its first light from the Cassiopeia A (Cas A), a supernova remnant somewhat over 11,000 light years away on 5 January 2024. During its performance verification phase, XSPECT was directed towards this standard celestial source used for instrument evaluation which is among the brightest radio frequency sources in the sky. The observation commenced on 5 January 2024, capturing the supernova remnant's emission lines corresponding to elements such as magnesium, silicon, sulphur, argon, calcium, and iron.
POLIX
XPoSat's POLIX sensor has started making scientific observations including first-ever data of x-ray polarisation of the Crab Pulsar, its first subject. The observation, which verified the POLIX instrument's operation, took place between January 15 and 18, 2024. POLIX monitored this fast-spinning neutron star in the Crab Nebula that releases roughly thirty X-ray pulses per second. Through the identification of polarization in its incoming X-rays, POLIX provides fresh perspectives on the physical emission processes at the surface of neutron stars. On 10 January 2024, the instrument was gradually turned on.
Solar Observations
In response to a massive Solar Flare in May 2024, XpoSAT, along with Aditya-L1 and the Chandrayaan-2 Orbiter colleected data on the event. XSPECT was used in conjunction with data from ground based observatories to provide fast timed and good spectroscopic results in the X-Ray spectra.
Payloads
Two payloads of XPoSat are hosted on a modified IMS-2 satellite bus. Primary scientific payload is Polarimeter Instrument in X-rays (POLIX) to study the degree and angle of polarisation of about 50 locally brightest astronomical X-ray sources of different types during its mission in the energy range 8-30 keV. POLIX, a instrument, was developed by the Raman Research Institute.
Polarimeter Instrument in X-rays (POLIX)
POLIX is the primary scientific payload aboard XPoSat. It is a Thomson X-ray polarimeter, which measures the degree and angle of polarization (polarimetry parameters) of astronomical sources in the medium X-ray range (8-30 keV). It has been developed by Raman Research Institute.
Its science objectives are to measure:
the strength and the distribution of magnetic field in the sources
geometric anisotropies in the sources
their alignment with respect to the line of sight
the nature of the accelerator responsible for energising the electrons taking part in radiation and scattering.
The experiment configuration consists of a collimator, central low Z (lithium, lithium hydride or beryllium) scatterer surrounded by xenon filled four X-ray proportional counters as X-ray detectors which collects the scattered X-ray photons. The instrument is rotated along the viewing axis leading to the measurement of the azimuthal distribution of the scattered X-ray photons which gives information on polarisation. Polarised X-rays will produce an azimuthal modulation in the count rate as opposed to uniform azimuthal distribution of count rate for unpolarised X-rays. POLIX has four independent detectors, each with its own front end and processing electronics. Localization of the X-ray photon in the detectors is carried out by the method of charge division in a set of resistive anode wires connected in series.
The prime objects for observation with this instrument are the X-ray bright accretion powered neutron stars, accreting black holes in different spectral states, rotation powered pulsars, magnetars, and active galactic nuclei. This instrument bridges an energy gap in detection capability, between the soft X-ray polarimeters utilising Bragg reflection (OSO-8) or Photoelectron tracks (IXPE), and hard X-ray polarimeters using Compton scattering such as the Cadmium Zinc Telluride Imager (CZTI) on AstroSat.
X-ray Spectroscopy and Timing (XSPECT)
XSPECT is the secondary payload on XPoSat. It measures spectroscopic information, timing of soft X-rays and electromagnetic spectrum generated by different types of matter. XSPECT is designed to pursue timing studies of soft X-rays (0.8-15 keV), complementary to what the Large Area X-ray Proportional Counter (LAXPC) does at high energies on AstroSat, while simultaneously providing adequate spectral resolution in the 1-20 keV band. It has an energy resolution of <200 eV at 5.9 keV (-20 °C) and a timing resolution of ~2 msec. It has been developed by the Space Astronomy Group of the U R Rao Satellite Centre.
The detector achieves modest effective area without the use of focusing optics using the large area Swept Charge Devices (SCD), a variant of X-ray charge-coupled Devices (CCDs). SCDs permit fast readouts (10–100 kHz) and moderately good spectral resolution at the cost of a position sensitivity. These devices are unique in requiring very benign cooling requirement (requiring only passive cooling) unlike traditional X-ray CCDs.
Key science objectives of XSPECT include understanding long-term behavior of X-ray sources through correlation of timing characteristics with spectral state changes and emission line variations.
See also
Imaging X-ray Polarimetry Explorer
List of X-ray space telescopes
X-ray astronomy satellite
X-ray telescope
References
{ INDIA’S PIONEERING X-RAY POLARIMETRY MISSION }
X-ray telescopes
Space telescopes
Satellites of India
2024 in India
2024 in spaceflight
Spacecraft launched in 2024 | XPoSat | [
"Astronomy"
] | 1,572 | [
"Space telescopes"
] |
61,430,825 | https://en.wikipedia.org/wiki/Sulcatone | Sulcatone (6-methyl-5-hepten-2-one) is an unsaturated methylated ketone with the molecular formula C8H14O. It is a colorless, water-like liquid with a citrus-like, fruity odor.
Sulcatone is one of a number of mosquito attractants, especially for those species such as Aedes aegypti with the odor receptor gene Or4.
References
Ketones | Sulcatone | [
"Chemistry"
] | 96 | [
"Ketones",
"Functional groups"
] |
61,432,067 | https://en.wikipedia.org/wiki/SISTINE | SISTINE (also known as SISTINE Mission and SISTINE Program) (acronym for "Suborbital Imaging Spectrograph for Transition region Irradiance from Nearby Exoplanet host stars") is a NASA mission designed to study distant stars as a way of finding life on exoplanets.
The technology to be employed is up to 100 times the UV spectroscopic ability of the Hubble Space Telescope.
The first test of the mission was launched on a Black Brant 9 rocket, a two-stage sounding rocket, at White Sands Missile Range, New Mexico, on 11 August 2019. This suborbital rocket can carry a payload of up to 1200 pounds, which, in the case of SISTINE, includes spectrographic equipment capable of covering the far ultra-violet spectral range of 100 to 160 nm, well suited to study strong atomic emission lines associated with the formation temperatures in the atmospheres of low-mass stars, and their effects on the potential atmospheres of exoplanets.
The second launch of SISTINE occurred on 8 November 2021. This launch focused on observing the spectra of Procyon A.
A third launch occurred on 6 July 2022 at 13:47 UTC from the Arnhem Space Centre in Nhulunbuy, Australia, reaching an apogee of . This launch focused on the spectra of Alpha Centauri A and B in the Alpha Centauri system which contains three stars and Proxima Centauri b, the closest exoplanet to the Earth.
The principal investigator of the mission is astronomer Kevin France, Assistant Professor at the Department of Astrophysical and Planetary Sciences, Laboratory for Atmospheric and Space Physics, University of Colorado in Boulder, Colorado.
See also
Sounding rocket
Ultraviolet astronomy
Ultraviolet–visible spectroscopy
References
Astrobiology
Astronomical observatories
Suborbital spaceflight | SISTINE | [
"Astronomy",
"Biology"
] | 374 | [
"Origin of life",
"Astronomical observatories",
"Speculative evolution",
"Astrobiology",
"Astronomy organizations",
"Biological hypotheses",
"Astronomical sub-disciplines"
] |
61,434,473 | https://en.wikipedia.org/wiki/C6H12N2O3 | {{DISPLAYTITLE:C6H12N2O3}}
The molecular formula C6H12N2O3 (molar mass: 160.17 g/mol, exact mass: 160.0848 u) may refer to:
Daminozide
Gamma-Glutamylmethylamide | C6H12N2O3 | [
"Chemistry"
] | 69 | [
"Isomerism",
"Set index articles on molecular formulas"
] |
61,434,721 | https://en.wikipedia.org/wiki/C25H28O5 | {{DISPLAYTITLE:C25H28O5}}
The molecular formula C25H28O5 (molar mass: 408.49 g/mol, exact mass: 408.1937 u) may refer to:
Debromomarinone
Isoemericellin
Molecular formulas | C25H28O5 | [
"Physics",
"Chemistry"
] | 64 | [
"Molecules",
"Set index articles on molecular formulas",
"Isomerism",
"Molecular formulas",
"Matter"
] |
61,435,097 | https://en.wikipedia.org/wiki/Athel%20Cornish-Bowden | Athel Cornish-Bowden (born 3 April 1943) is a British biochemist known for his numerous textbooks, particularly those on enzyme kinetics and his work on metabolic control analysis.
Education and career
Athel Cornish-Bowden worked on pepsin catalysis. This began a life long pursuit of work on enzyme catalysis and in later years work on the control of metabolism. More recently he has also turned his attention to work related to the origin and nature of life.
He obtained his D.Phil. at Oxford with Jeremy R. Knowles, and carried out post-doctoral work with Daniel E. Koshland Jr.
Research
Cornish-Bowden has authored over 200 peer-reviewed papers and nine textbooks on topics related to enzyme kinetics, mathematics and historical perspectives in science. According to Google Scholar, the textbook, Fundamentals of enzyme kinetics, has been cited over 3000 times by secondary sources.
Cornish-Bowden's research can be divided into three primary areas: Enzyme kinetics, metabolic control, done mainly in collaboration with Jannie Hofmeyr, and the origin of life. The following lists some of the topics and selected references to the work carried out and published by Cornish-Bowden:
Mechanisms of Pepsin Catalysis
Binding of ligands to Proteins
Kinetics of nitrite reductase
Kinetics of nitrate reductase
The evolution of macromolecules
Properties of multienzyme systems
The theory of self-organizing systems
Additionally, Cornish-Bowden has published a number of history of science papers commemorating the lives and achievements of historical figures in enzymology. His current interests include the definition of life and the capacity for life to self-organize.
Major research contributions
Cornish-Bowden is most well known for his introduction of the direct-linear plot for estimating enzyme parameters, his work on Hexokinase evolution and kinetics, and his insight into the control and regulation of metabolism.
Editorial and related work
Cornish-Bowden has participated on the editorial boards of various journals (the Biochemical Journal, the Journal of Theoretical Biology, FEBS Journal, BioSystems), and has been active on International Committees. He was secretary of the IUPAC-IUBMB Joint Committee on Biochemical Nomenclature
and in that capacity convened the committee that prepared the current IUBMB recommendations on enzyme kinetics.
He also contributed to recommendations on biochemical thermodynamics, and to proposals for system representation of biochemical networks.
Books
Fundamentals of Enzyme Kinetics
References
Systems biologists
Theoretical biologists
1943 births
Living people
British biochemists
Alumni of Wadham College, Oxford
British textbook writers
People from Ashburton, Devon | Athel Cornish-Bowden | [
"Biology"
] | 543 | [
"Bioinformatics",
"Theoretical biologists"
] |
61,437,188 | https://en.wikipedia.org/wiki/C25H41NO7 | {{DISPLAYTITLE:C25H41NO7}}
The molecular formula C25H41NO7 (molar mass: 467.60 g/mol, exact mass: 467.2883 u) may refer to:
Delsoline
Lycoctonine
Molecular formulas | C25H41NO7 | [
"Physics",
"Chemistry"
] | 63 | [
"Molecules",
"Set index articles on molecular formulas",
"Isomerism",
"Molecular formulas",
"Matter"
] |
61,437,236 | https://en.wikipedia.org/wiki/Qarhan%20Playa | The Qarhan Playa or also misleadingly described as , is a playa in the Golmud and Dulan counties of Haixi Prefecture, Qinghai, China. Formerly a single unitary lake, it is now an expansive salt flat divided into four greater sections (Dabusun, Big/Small Bieletan, Suli, and N./S. Huoluxun) which contain a number of smaller salt lakes, the largest of which is Dabusun Lake. The area is heavily exploited for its valuable salt, mineral, and rare earth reserves but parts are also protected as a national park and contribute to regional tourism.
Name
Qarhan is the GNC romanization of the area's Mongolian name, originally derived from the word for "white" (Modern , tsagaan, or , čaɣan). Cha'erhan is the pinyin romanization of the Mandarin pronunciation of , a modification of the original transcription into Chinese characters of the same name; it is also sometimes clipped into Charhan in English sources. The Chinese name, which does not distinguish between actual salt lakes and playas, also causes the playa to be called a "lake" or even "the largest salt lake in China" in less careful English sources.
Geography
The Qarhan Playa covers an area of , stretching over east to west and usually between north to south. The southwest lies in Golmud and the northeast in Dulan County, both in Haixi Prefecture, Qinghai, China. The roughly area of Qarhan inclusive of Taijinar to its west is sometimes known as the Sanhu ("Three Lakes"), after the two Taijinar lakes, Suli Lake, and Dabusun. Qarhan is part of the larger Qaidam Basin, lying between the Kunlun Mountains to the south, the Altun to the west, and the Qilian to the north. Qarhan's lakes lie between above sea level, with Dabusun and North Hulsan being the lowest and Xiezuo being the highest. The effect of elevation is such that despite lying on the same latitude as Greece, Algeria, and Virginia in the United States, Qarhan has a mean annual temperature of . The mean air speed is , and the mean relative humidity is 27.7%.
In the playa's hyperarid climate, there is generally only of annual rainfall but of annual evaporation. Despite this, meltwater rivers and mineral springs fill the basins of the salt flat's four main sectionsBieletan, Dabusun, Qarhan, and Huoluxunwith about ten large but shallow lakes usually collectively occupying an area of about : Suli Lake in the west, fed from the west by the Urt Moron; the Little and Big Biele Lakes beside it, fed from the south by the Tuolahai and Qingshui Rivers; West Dabusun and Dabusun Lake (the largest), in the center, fed from the south by the Golmud River; Dongling Lake to their northwest; Xiezuo and Tuanjie Lakes to their east, fed respectively by the intermittent Quanji and Shougong Rivers; and North and South Hulsan Lakes at the east end of the playa, fed from the east by the Qaidam, Nuomuhong, and Suolinguole Rivers. All of these are usually less than deep. There are also some ephemeral lakes. Most of the streams contributing to these lakes flow north into the playa from the Kunlun and its foothills. The Golmud River is the main contributor, providing a mean annual influx of 19.2 trillion L (5.07 trillion gal) of water. There is also contribution of about 1% from mineral springs, especially on the north end of the playa, which play an important role in the chemical composition of the sediment.
The local flora consists of sparse forbs (particularly members of Chenopodioideae) and shrubs, especially members of Ephedra and Tamarix.
Geology
Most of the Qarhan Playa is solid halite underlain by a layer of brine to about under the soil, and it holds enormous reserves of salt, with solid layers extending between . The 50 billion metric tons (55 billion short tons) are estimated sufficient to meet present world demand for 1,000 years. The area around Dabusun Lake has halite to depths of at least , although with alternating layers of mud in places. The salinity of the playa's lakes varies between 164.81 and 359.50 g/L (1.3–3 lb/gal); their pH values are between 5.4 and 7.85.
Other minerals include potash, carnallite (potassium magnesium chloride), calcium chloride, magnesium, lithium, boron, iodine, and sylvite. The basin is one of China's richest sources for potassium, with an estimated of potassium oxide. Its reserves are also important as the world's largest present-day accumulation of potassium-rich salt in the world, which helped scientists better understand the chemical and evaporation pathways involved in the creation of natural potash and disprove previous suppositions that it only formed in marine environments. The Bieletan subbasin in the west is the richest source of brine lithium in China, with an estimated reserve of of lithium chloride. The Sanhu as a whole holds 83% of the country's known lithium reserves, with some areas having concentrations of 330 ppm.
History
Paleoclimatologists believe that the playa's basin was created by tectonic activity during the Mesozoic. Between 770,000 and 30,000 years ago the basin constituted an enormous lake, which alternated nine times between being a fresh- and saltwater lake. Pollen studies suggest that the area of the lake bed which now underlies Dabusun was raised around in just the last 500,000 years. Tectonic activity also shifted the lake's tributaries and basins, although it remained with the present-day playa during this period. At around 30,000 years ago, this great freshwater lake spread over at least with a surface above the present levels of its successors, making it one of the largest lakes in the world. It was cut off and became saline again around 30,000 years ago and began precipitating salts about 25,000 years ago. It has been shrinking in size by evaporation for most of that time, eventually separating into the current separate lakes.
Until the recent commercial exploitation of the salts and other minerals, the district remained largely unpopulated, as the salt deposits made it difficult for the nomads of northwestern China to use the area for their herds.
National geological expeditions began investigating Qinghai in the 1950s, shortly after the establishment of the People's Republic of China. The major expedition to the Qarhan Playa was undertaken in 1955–6, but the area's important carnallite (and thus potassium) reserves were discovered accidentally by geologists Zheng Mianping and Liu Dagang during a stroll on 2 October 1957. The next year, an exploratory well discovered the Yanhu Gas Field north of Dabusun Lake. Over the next decade, more detailed surveying and prospecting were undertaken while China continued to depend on Canadian imports for its potash. Commercial exploitation of the basin's own potash began in 1989, following the expansion of the PRC's Opening Up and Reform Policy. The opening of the Qinghai Potash Fertilizer Factory increased China's production of potassium chloride sixfold, from less than a year at Haixi and Tanggu to just under a year. As of 2010, production was over a year at the main site, with smaller operations around the playa each producing a further a year.
During a 2016 inspection tour, Chinese Communist Party general secretary Xi Jinping praised the importance of the factories and their workers to the entire country but emphasized the need for Qarhan's development to be environmentally responsible. As part of a national program to increase the use of electric cars, automobile companies like BYD have since moved to the area, opened factories, and signed contracts with local mining companies to exploit the area's lithium supplies. Infrastructure has been improved, including an overhaul of Golmud Airport.
Tourism
The fertilizer factory is now open to the public for free tours, and its parent company maintains a nearby museum covering the geology of the playa and hosting various salt sculptures. The area was designated a national mining park on 1 August 2008.
Transportation
Sections of the G3011 Liuge Expressway and the Qingzang Railway run over the playa's salt flats.
See also
List of lakes and salt lakes in China
Notes
References
Citations
Bibliography
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Salt flats
Salt flats of China
Geography of Qinghai
Haixi Mongol and Tibetan Autonomous Prefecture | Qarhan Playa | [
"Chemistry"
] | 1,852 | [
"Salt flats",
"Salts"
] |
75,115,310 | https://en.wikipedia.org/wiki/Peter%20Gill%20%28chemist%29 | Peter Malcolm Wallace Gill (born 9 November 1962) is a New Zealand theoretical and computational chemist known for his contribution to density functional theory (DFT). He is an early and main contributor to the computational chemistry software Q-Chem and was the president of the company during 1998–2013. He is especially known for developing the PRISM algorithm for evaluating two-electron integrals and linear-scaling DFT, as well as self-consistent field method for excited state electronic structure.
Education and career
Gill was born in Auckland and received his BSc in 1983 and MSc in 1984 from the University of Auckland. He received a PhD in 1988 from the Australian National University under the supervision of Leo Radom. During this time, he investigated hemi-bonding and the convergence of perturbation theory in quantum chemistry. After graduation, he conducted postdoctoral work with John Pople at Carnegie Mellon University from 1988 to 1993. Following this stint, Gill accepted a lectureship at Massey University in 1993. He became a lecturer at the University of Cambridge in 1996. In 1999, Gill became the inaugural chair of theoretical chemistry at the University of Nottingham. He moved to Australia and became a professor at the Australian National University in 2004 and later moved to the University of Sydney in 2019 as the Schofield Chair in Theoretical Chemistry.
In 2001, Gill wrote an essay pronouncing the demise of density functional theory thanks to the rise of hybrid functionals for exchange interactions between electrons.
Honors and awards
Gill is the president of the World Association of Theoretical and Computational Chemists (WATOC) and received the Dirac Medal in 1999 and the Schrödinger Medal in 2011 from WATOC.
In 2013, Gill received the Fukui Medal from APATCC.
Gill was elected a Fellow of the Australian Academy of Science in 2014 and received the David Craig Medal from the Australian Academy of Science in 2019. In 2015 Gill was inducted to the International Academy of Quantum Molecular Science.
References
Living people
1962 births
New Zealand chemists
Scientists from Auckland
University of Auckland alumni
Australian National University alumni
Academic staff of the Australian National University
Academics of the University of Cambridge
Academics of the University of Nottingham
Academic staff of the University of Sydney
Computational chemists
Theoretical chemists
Fellows of the Australian Academy of Science
Academic staff of Massey University | Peter Gill (chemist) | [
"Chemistry"
] | 456 | [
"Quantum chemistry",
"Physical chemists",
"Computational chemists",
"Theoretical chemistry",
"Computational chemistry",
"Theoretical chemists"
] |
75,115,441 | https://en.wikipedia.org/wiki/DARPA%20lunar%20programs | Recognizing the rapid lunar exploration, DARPA envisions a thriving cislunar and lunar economy of scientific research and commercial development over the next decade. It has launched two programs to address the need for shareable, scalable commercial systems essential to a robust lunar economy.
Lunar Guidelines for Infrastructure Consortium (LOGIC)
LOGIC intends to bring industry, academia, and government together to identify critical lunar infrastructure interoperability and interface needs for commercial lunar infrastructure.
In October 2023, the Johns Hopkins University (JHU) Applied Physics Laboratory (APL) was selected to administer LOGIC as a permanent, self-sustaining, and independent forum for collaboration.
10-Year Lunar Architecture (LunA-10)
Announced in August 2023, LunA-10 will conduct a seven-month capability study to create core technology concepts toward a series set of adaptable, expandable systems that can work together and be shared, “minimizing lunar footprint and creating monetizable services for future lunar users.” The study is tailored to capabilities for commercial and economic uses, and will not be for military applications.
The LunA-10 study’s focus areas are based on key sectors identified in a report titled “Lunar market assessment: market trends and challenges in the development of a lunar economy” by PwC Australia in September 2021. Transit/mobility, energy, and communications are the three areas LunA-10 sees as forming the foundation of any other lunar industries. Industries that may integrate technologies into the LunA-10 infrastructure include construction, mining, medicine, sciences, communications, etc. In December 2023, 14 companies were funded to complete the study by June 2024 about the necessary infrastructure and capabilities required to develop a moon-based economy over the next ten years. They include Blue Origin, CisLunar Industries, Crescent Space Services, Fibertek, Inc., Firefly Aerospace, GITAI, Helios, Honeybee Robotics, ICON, Nokia of America, Northrop Grumman, Redwire Corporation, Sierra Space and SpaceX. For example, aerospace company Northrop Grumman will provide a conceptual study of a “lunar railroad” network for commercial ventures.
NASA has been working on a detailed architecture for lunar and Martian exploration. DARPA has coordinated with NASA to make LunA-10 complementary to NASA architecture studies.
An update on the program occurred in April 2024. With industry participants providing insight on how a lunar economy could be operationalized. Many proposals relied on the viability of in-situ resource utilization and low enough launch costs.
See also
Colonization of the Moon
NASA lunar outpost concepts
Lunar Architecture (NASA)
Space architecture
Exploration Systems Architecture Study
Moon Treaty
Outer Space Treaty
Lunar resources
Space industry
Demonstration Rocket for Agile Cislunar Operations (DRACO)
External links
NASA’s Lunar Surface Innovation Initiative
LOGIC
10-Year Lunar Architecture Capability Study (LunA-10)
NASA: A Researcher’s Guide to: Space Environmental Effects
NASA: Moon to Mars Architecture
Space Environment Exploitation (SEE)
References
Exploration of the Moon
Human spaceflights
Spaceflight | DARPA lunar programs | [
"Astronomy"
] | 609 | [
"Spaceflight",
"Outer space"
] |
75,115,484 | https://en.wikipedia.org/wiki/ASASSN-21qj | ASASSN-21qj, also known as 2MASS J08152329-3859234, is a Sun-like main sequence star with a rotating disk of circumstellar dust and gas which are leftovers from its stellar formation around 300 million years ago. The star is located 1,850 light years (567.2 parsecs) from Earth in the constellation of Puppis.
Planetary collision event
In 2021 the All-Sky Automated Survey for Supernovae reported that this star was rapidly fading. The published Astronomer's Telegram asked for follow-up observations. On twitter the astronomers Dr. Matthew Kenworthy and Dr. Eric Mamajek speculated about this object and amateur astronomer Arttu Sainio made his own investigation and discovered a brightening in NEOWISE data. He then joined the discussion on social media. The star brightened 2.5 years before the dimming event. More contributions came from amateur and professional astronomers, such as spectroscopic follow-up by amateur astronomers Hamish Barker, Sean Curry and the amateur Southern Spectroscopic project Observatory Team (2SPOT) members Stéphane Charbonnel, Pascal Le Dû, Olivier Garde, Lionel Mulato and Thomas Petit. Dr. Franz-Josef Hambsch observed this object with his remote observatory ROAD and submitted his observations to AAVSO. Other observations from professional telescope include ATLAS, ALMA, LCOGT and TESS.
In 2023, a scientific paper reported observations consistent with two ice-giant type exoplanets of several to tens of Earth masses having undergone a planetary collision event. The collision occurred at a distance of 2-16 AU (astronomical units) from the star. The infrared brightening is thought to be the result of dust produced by the disruption being heated by the collision, reaching a temperature of 1000 K (727°C; 1340°F) and then the dust slowly cooled off and expanded in size. Together with the newly formed planet, the dust cloud orbited the star and 1000 days later the dust moved in front of the star, causing a dimming event. Because of the dust cloud had now reached a large size, the dimming event would last for 600 days. The newly formed planet did not cause a transit.
Another work also studied the event in detail and concluded that the event was produced by the breakup of exocomets. This paper was later mentioned in an author correction of the first work. The system has been observed with JWST, with the data being studied by researchers.
A few other planetary collisions were discovered in the past, such as around NGC 2547–ID8, HD 166191 and V488 Persei.
See also
List of extrasolar planetary collisions
BD+20°307
References
Puppis
J08152329-3859234 | ASASSN-21qj | [
"Astronomy"
] | 577 | [
"Puppis",
"Constellations"
] |
75,116,198 | https://en.wikipedia.org/wiki/LGBT%20life%20expectancy | The life expectancy of lesbian, gay, bisexual and transgender (LGBT) people is a subject of research. Early research by the Cameron group purporting to find a significantly shorter life expectancy among homosexuals is not considered reliable, although it has been widely misused and cited. During the AIDS crisis, a loss in average life expectancy was observed among gay men.
In the late 2000s, research suggested "the claims of drastically increased overall mortality in gay men and lesbians appear unjustified". As of 2020, data from Sweden found no gap in mortality between homosexual and heterosexual individuals, although mortality may be higher in bisexuals. A 2022 study in the United States found no excess mortality among gay and bisexual males, but found excess mortality among bisexual and lesbian females.
There is not yet reliable research on life expectancy of transgender people, although false statistics have been widely circulated.
Gay and bisexual life expectancy
Flawed claims of significantly shorter life expectancy
Cameron studies
Early studies by the Paul Cameron purported to find that homosexuals had a life expectancy 20 to 30 years shorter than heterosexuals, however due to its methodology it has been criticized as unreliable. Cameron's work was described as "just ridiculous" by demographer Nicholas Eberstadt at the conservative American Enterprise Institute; and the epidemiologist Morten Frisch described his work ''of such a grave nature that no decent peer-reviewed scientific journal should let it pass for publication". Cameron had relied on newspaper obituaries which clearly referred to sexual orientation, with bias in sampling and errors in statistical technique. In the 1980s, Cameron was expelled from the American Psychological Association for violations.
Hogg et al.
Another study published in 1998 by Hogg et al. modelled the impact of AIDS deaths in Vancouver between 1987 and 1992, using a sample of men who attended a sexual health clinic, and estimated a loss of average life expectancy in the gay and bisexual population between 8 and 20 years. The authors released a statement in 2001 clarifying that their findings were relevant to the AIDS crisis, but were no longer relevant at the time of publication as AIDS deaths had fallen significantly, primarily due to antiretroviral therapy.
Misuse
Despite the flaws of Paul Cameron's research, and the limited applicability of the Hogg study, many anti-gay groups and individuals have cited these studies to characterize homosexuality as inherently unhealthy. Paul Cameron's research group has claimed that homosexuality is "as dangerous to public health as drug abuse, prostitution, and smoking". In 1997, the U.S. secretary of education William Bennett claimed that gay men die at 43 years during a television interview, a figure from a flawed Cameron study.
In response to frequent misuse, Hogg et al. clarified their findings were no longer applicable in 2001. In 2003, the economist Walter E. Williams cited the Hogg study to argue that homosexuals should pay more for life insurance, stating "that's a lifestyle shortening of life expectancy greater than obesity and tobacco use". In 2012, the Australian Anglican Archbishop Peter Jensen made similar claims on national television.
Frisch 2009 and 2013 studies
The Danish epidemiologist Morten Frisch carried out more robust research in 2009 using marriage data from Denmark. His study found excess mortality was limited to the first few years of marriage, consistent with some men who had preexisting illnesses (e.g. HIV/AIDS) marrying and dying. Frisch stated "we observed a drastic reduction from 9.63 excess deaths per 1000 person-years among those who married their partner in the pre-HAART period to 1.53 excess deaths per 1000 person-years for those who married during the HAART period". According to Frisch, "the claims of drastically increased overall mortality in gay men and lesbians appear unjustified".
In 2013, Frisch also carried out another study which found excess mortality in homosexual men had shrunk further. It linked same-sex marriage with increases in life expectancy.
2014 retraction
A 2014 study by Hatzenbuelher et al. purported to find that sexual minorities living in areas with high levels of anti-gay prejudice had their life expectancy reduced by 12 years. However, it was retracted in 2019 when it was discovered there was a coding error in the data, and that after correcting the error it "rendered the association between structural stigma and mortality risk no longer statistically significant".
2020 Swedish mortality study
A 2020 study in Sweden found that mortality among homosexual men and women did not significantly differ from heterosexuals, although it was elevated for bisexual men and women.
2022 United States mortality study
A 2022 study in the United States found no excess mortality among gay or bisexual males, but there was excess mortality among sexual minority females.
Transgender life expectancy
According to Bosson et al. "the systematic research needed to determine the average life expectancy of transgender people has not yet been conducted".
One unsubstantiated statistic widely circulated in the media claims that the life expectancy of transgender women of color (sometimes transgender women in general) is only 35 years old; however, this is not corroborated by any research. According to sociologist Laurel Westbrook, this inaccurate statistic was calculated by averaging the age of transgender murder victims. This is an erroneous methodology for calculating life expectancy, as murder victims are not a representative population of transgender people.
Several studies have been conducted that indicate that transgender individuals have an increased mortality rate, however these studies have not modelled life expectancy.
See also
Life expectancy
Anti-LGBT rhetoric
Epidemiology
References
Health care
LGBT
Public health | LGBT life expectancy | [
"Biology"
] | 1,154 | [
"Senescence",
"Life expectancy"
] |
75,117,289 | https://en.wikipedia.org/wiki/Hexagonia%20vesparia | Hexagonia vesparia, sometimes known as the wasp nest polypore, is a bracket fungus in the Polyporaceae family occurring mainly in tropical and coastal regions in Australia, but it has also been recorded in semi arid regions of Australia. The genus name came from the Latin word hexagonus meaning with six angles.
Description
Wasp nest polypore is an irregular hoof shaped bracket fungus approximately 25–80mm in diameter. With its hexagonal and radially elongated pores it gives the fungus the appearance of a wasp nest. The flesh has a hard woody texture that extends about five centimetres from the substrate with pores that change in colour from off white to dark brown depending on age. The spores are smooth and cylindrical 14–17 × 5–7 micrometres. The upper surface attached to the substrate can be hairy and has bumps and groves that look like channels
Distribution
Hexagonia vesparia has it greatest known distribution in Victoria, NSW and Perth, and sparingly in the Northern Territory, South Australia and Queensland. Fungal surveys have been limited in Australia with the focus on fauna and flora, however fungi are starting to be included, and recordings of Hexagonia vesparia and other fungi species are likely to expand distribution areas.
Habitat and ecology
Wasp nest polypore are found on both branches and trunks of living trees and dead logs in rainforest and wet sclerophyll forest, however they have been recorded in more semi arid areas of Eucalypt Mallee Woodland. Fungi are categorised into groups dependant on their shape, form, texture and function, known as morphogroups. Wasp nest polypore are categorised as fungi with pores and are saprophytic fungi, which is the largest macro fungi group.
Saprophytic fungi are the recyclers of an ecosystem and breakdown organic material by releasing an enzyme which absorbs lignin, cellulose or chitin from the material and turns it into a soluble compound for itself and that of other plants in the way of nutrients. They play a vital role in cleaning up dead material in forests and recycling nutrients such as carbon and nitrogen.
Reproduction
What is most visible of the bracket fungi is the reproductive fruiting bodies (basidiocarp) or the spore-bearing structure which extends out of the substrate. On the underside of the bracket are spore-producing tubes (basidium). Basidiomycota reproduce sexually and for germination to occur on the substrate, haploid spores of two different mating strains fuse (karyogamy),to produce dikaryotic a diploid zygote. The haploid basidiospores are dispersed through the air to other trees or by water drops, dropped onto dead logs. Thin elongated structures called (hyphae) form a network within the wood on which bracket fungi grow, these collective hyphae create the mycelium that extends into the wood, and colonises the host substrate.
Conservation
Hexagonia as a genus has no significant conservation concerns in Queensland and is not threatened in Western Australia. and other states in Australia have not listed any conservation status, however disturbances such as too frequent fire regimes and land clearing could cause a decline in this species because of the lose of their host. Further research is required to better understand the fire response of this species, however retaining dead wood - trees, logs and other organic matter in ecosystems promote diverse fungi species creating a resilient ecosystem.
References
Polyporaceae
Fungi of Australia
Endemic flora of Australia
Fungi described in 1839
Taxa named by Miles Joseph Berkeley
Fungus species | Hexagonia vesparia | [
"Biology"
] | 740 | [
"Fungi",
"Fungus species"
] |
75,118,592 | https://en.wikipedia.org/wiki/Expedition%2072 | Expedition 72 is the 72nd long-duration expedition to the International Space Station (ISS). The expedition began with the departure of Soyuz MS-25 on 23 September 2024 and is led by Sunita Williams, her second time serving as commander of the ISS. It will continue the extensive scientific research conducted aboard the ISS, focusing on various fields, including biology, human physiology, physics, and materials science. The crew members will also maintain and upgrade the space station systems.
Background, Crew, and Events
The expedition consists of Roscosmos cosmonauts Aleksey Ovchinin, Ivan Vagner, and Aleksandr Gorbunov, and NASA astronauts Barry E. Wilmore, Sunita Williams, Donald Pettit, and Nick Hague.
Wilmore and Williams arrived at the station on 6 June 2024 for what was expected to be a brief visit as part of the Boeing Crew Flight Test mission. However, their spacecraft experienced technical issues and returned to Earth uncrewed, and Wilmore and Williams were added to the Expedition 71/72/73 crew.
Ovchinin, Vagner, and Pettit arrived at the station on 11 September aboard Soyuz MS-26. Hague and Gorbunov arrived to the station on 29 September aboard SpaceX Crew-9. After a handover period, SpaceX Crew-8 departed on 23October.
In March 2025, SpaceX Crew-10 is expected to arrive, transporting NASA astronauts Anne McClain and Nichole Ayers, JAXA astronaut Takuya Onishi, and Roscosmos cosmonaut Kirill Peskov.
Roscosmos cosmonauts Sergey Ryzhikov and Alexey Zubritsky, along with NASA astronaut Jonny Kim, are expected to arrive at the station aboard Soyuz MS-27 in March 2025.
Expedition 72 will come to a close in March 2025 with the departure of Ovchinin, Vagner, and Pettit on Soyuz MS-26.
Crew
Notes
References
NASA
2024 in spaceflight
September 2024
Spaceflight
Expeditions to the International Space Station | Expedition 72 | [
"Astronomy"
] | 433 | [
"Spaceflight",
"Outer space"
] |
75,118,593 | https://en.wikipedia.org/wiki/Expedition%2073 | Expedition 73 will be the 73rd long-duration expedition to the International Space Station (ISS). The expedition will begin with the departure of Soyuz MS-26, expected to take place in March 2025. Takuya Onishi of the Japan Aerospace Exploration Agency (JAXA) will serve as the commander of the expedition, the third JAXA astronaut to take command of the station. It will continue the extensive scientific research conducted aboard the ISS, focusing on various fields, including biology, human physiology, physics, and materials science. The crew members will also maintain and upgrade the space station systems.
References
NASA
2025 in spaceflight
March 2025
Spaceflight
Expeditions to the International Space Station | Expedition 73 | [
"Astronomy"
] | 141 | [
"Outer space stubs",
"Spaceflight",
"Astronomy stubs",
"Outer space"
] |
75,118,641 | https://en.wikipedia.org/wiki/Soyuz%20MS-26 | Soyuz MS-26, Russian production No. 757 and identified by NASA as Soyuz 72S, is a Russian crewed Soyuz spaceflight launched from Site 31/6 at the Baikonur Cosmodrome on 11 September 2024 to the International Space Station. The mission transported three crew members, Roscosmos cosmonauts Aleksey Ovchinin and Ivan Vagner, along with NASA astronaut Donald Pettit.
When the spacecraft crossed the Karman line shortly after launch, there were a record 19 people in outer space: the three astronauts on the MS-26 mission, three more on China's Tiangong space station, four people on the SpaceX Polaris Dawn mission, and nine more on board the International Space Station.
Crew
Notes
References
External links
2024 in spaceflight
September 2024 events in Russia
September 2024 events in Kazakhstan
Crewed Soyuz missions
International Space Station
Baikonur Cosmodrome
Kyzylorda Region | Soyuz MS-26 | [
"Astronomy"
] | 196 | [
"Outer space stubs",
"Outer space",
"Astronomy stubs"
] |
75,118,664 | https://en.wikipedia.org/wiki/International%20Quiet%20Ocean%20Experiment | The International Quiet Ocean Experiment (IQOE) is a global scientific research program aimed at improving understanding of the distributions of sounds in the ocean, and studying the effects of underwater noise pollution on marine life. The program has worked on promoting research, observations, and modelling to advance understanding of ocean soundscapes and the effects of sound on marine organisms. The IQOE was launched in 2015 by the Scientific Committee on Oceanic Research (SCOR) and the Partnership for Observation of the Global Ocean (POGO). The program comprises an international consortium of scientists, industry partners, and governmental organizations working together to further understanding of the impact of underwater noise on the ocean environment.
History
The idea for the IQOE first took shape in 2011 during a workshop hosted by the Scientific Committee on Oceanic Research (SCOR) and the Partnership for Observation of the Global Ocean (POGO). This workshop brought together scientists from various disciplines and countries who recognized the need for a coordinated global effort to understand the effects of underwater noise.
Products
IQOE groups have produced a variety of products to accomplish the goals of the project:
IQOE Science Plan--Published in 2015, the IQOE Science Plan provides the scientific and societal rationales for the project and lays out actions designed to accomplish project goals. The plan is based on an open science meeting held in Paris, France in 2011 at the Intergovernmental Oceanographic Commission headquarters.
IQOE Newsletters--IQOE documents its activities and progress in 2-3 newsletters released each year.
Guidelines for Observation of Ocean Sound--This workshop report compiles the work of several IQOE-endorsed projects, as well as the IQOE WG on Standardization to recommend standards for passive ocean acoustic observations.
Listening forward: approaching marine biodiversity assessments using acoustic methods--This paper was produced by the IQOE Working Group on Acoustic Measurement of Ocean Biodiversity Hotspots to document the state of the science on using bioacoustic metrics to estimate marine biodiversity.
References
Noise pollution
Ocean pollution | International Quiet Ocean Experiment | [
"Chemistry",
"Environmental_science"
] | 404 | [
"Ocean pollution",
"Water pollution"
] |
75,118,682 | https://en.wikipedia.org/wiki/10G | 10G is a term used by some cable Internet access providers and industry groups in the United States in reference to broadband networks with a maximum potential download rate of ten gigabits per second (10 Gbit/s). The term was first used in this regard by industry association NCTA in January 2019, which said it had filed for a trademark on the term, and expanded on by CableLabs in a summer 2019 white paper.
The term "10G" has no connection to the numbered generations of cellular network standards such as 5G (fifth generation). Some articles discussing the term have posited that 10G suggests to casual readers that service would be twice as fast as 5G, when in fact the 5G standard already encompasses even faster speeds of up to 20 Gbit/s.
In early 2023, Comcast began referring to its Xfinity Internet service as now being on a "10G network", despite the fact that the top-speed service available in the vast majority of homes served by Comcast was still only 1 Gbit/s.
In October 2023, the National Advertising Division (NAD) of the Better Business Bureau ruled that it considered Comcast's use of 10G to be false or misleading, as it constituted an express claim that Comcast was using a tenth-generation network or was promising 10 Gbit/s speeds to all customers. The NAD recommended that Comcast should either discontinue its claims or clarify 10G as an "aspirational" technology. Comcast said it would appeal the decision by the self-regulatory body. However, by January 2024, Comcast said it would no longer use the "10G Network" branding in marketing.
See also
10 Gigabit Ethernet – a set of technologies for Ethernet communications that support up to 10 Gbit/s speeds
10G-PON and 10G-EPON – passive optical network standards that support up to 10 Gbit/s speeds
References
Internet access
Internet terminology
Comcast | 10G | [
"Technology"
] | 409 | [
"Internet access",
"IT infrastructure",
"Internet terminology",
"Computing terminology"
] |
75,118,815 | https://en.wikipedia.org/wiki/Common%20symbiosis%20signaling%20pathway | The common symbiosis signaling pathway (CSSP) is a signaling cascade in plants that allows them to interact with symbiotic microbes. It corresponds to an ancestral pathway that plants use to interact with arbuscular mycorrhizal fungi (AMF). It is known as "common" because different evolutionary younger symbioses also use this pathway, notably the root nodule symbiosis with nitrogen-fixing rhizobia bacteria. The pathway is activated by both Nod-factor perception (for nodule forming rhizobia), as well as by Myc-factor perception that are released from AMF. The pathway is distinguished from the pathogen recognition pathways, but may have some common receptors involved in both pathogen recognition as well as CSSP. A recent work by Kevin Cope and colleagues showed that ectomycorrhizae (a different type of mycorrhizae) also uses CSSP components such as Myc-factor recognition.
The AMF colonization requires the following chain of events that can be roughly divided into the following steps:
1: Pre-Contact Signaling
2: The CSSP2: A: Perception
2: B: Transmission
2: C: Transcription3: The Accommodation program
Outline
To accurately recognize the infection thread of a different species of organism, and to establish a mutually beneficial association requires robust signaling. AM fungi are also fatty acid auxotrophs; therefore they depend on a plant for supply of fatty acids.
At the pre-symbiotic signaling, plants and AMF release chemical factors in their surroundings so that the partners can recognise and find each other.' Plant root exudates play roles in complex microbial interaction, by releasing a variety of compounds, among which strigolactone has been identified to facilitate both AMF colonisation and pathogen infection.
Phosphate starvation in plant induces strigolactone production as well as AMF colonisation. Plants release strigolactone, a class of caroteinoid-based plant hormone, which also attracts the fungal symbionts, and stimulate the fungal oxidative metabolism along with growth and branching of the fungal partner. Strigolactone promotes hyphal branching in germinating AMF spores and facilitates colonisation.
The common symbiosis signalling pathway is called so because it has common components for fungal symbiosis as well as rhizobial symbiosis. The common signalling pathway probably evolved when the existing pathway for arbuscular mycorrhizae was exploited by rhizobia.
The perception happens when fungal Myc factor is detected by the plant. Myc factors are comparable to rhizobial nod factors. The chemical nature of some Myc-factors has recently been revealed as lipo-chito-oligosaccharide (Myc-LCOs) and chito-oligosaccharides (Myc-COs) that work as symbiotic signal.
The presence of Strigolactone enhances the production of Myc-CO production by AMF.
Myc-factor receptor (MFR) is still putative. However, a protein called DMI2 (or SYMRK) has a prominent role in perception process and it is thought to be a co-receptor of MFR. Other plants such as rice may employ different mechanisms using OsCERK1 and OsCEBiP to detect chitin oligomers. However, recent work has demonstrated that rice SYMRK is essential for AM symbiosis.
The transmission happens when the signal is transmitted after detection to the plant nucleus. This process is mediated by two nucleoporins NUP85 and NUP133, Alternatively, another hypothesis says HMG-CoA reductase is activated on perception, which then converts HMG-CoA into mevalonate. This mevalonate acts as a second messenger and activates a nuclear K+ cation channel (DMI-1 or Pollux). The transmission stage ends by creating a ‘calcium spike’ in the nucleus.
The transcription stage starts when a Calcium and Calmodulin dependent kinase (CCaMK) is activated. This kinase stimulates a target protein CYCLOPS. CCaMK and CYCLOPS probably forms a complex that along with DELLA protein, regulates the gene expression of RAM1 (Reduced Arbuscular Mycorrhyza1).
The accommodation process involves the extensive remodelling of host cortical cells. This includes invagination of host plasmalemma, proliferation of endoplasmic reticulum, golgi apparatus, trans-golgi network and secretory vesicles. Plastids multiply and form “stromules”. Vacuoles also undergoe extensive reorganization.
The Pre-Contact Signaling
Chemical signalling starts prior to the two symbionts coming into contact. From the host plant's side, it synthesizes and releases a range of caroteinoid based phytohormone, called strigolactones. They have a conserved tricyclic lactone structure also known as ABC rings. Strigolactone biosynthesis occurs mainly in plastid, where D27 (Rice DWARF 27; Arabidopsis ortholog ATD27), an Iron binding beta-carotene isomerase works at upstream of strigolactone biosynthesis. Then carotenoid cleavage dioxygenase enzyme CCD7 and CCD8 modifies the structure, which has following orthologs:
The alpha/beta fold hydrolase D3 and also D14L (D14-Like) (the later one has an Arabidopsis ortholog, KAI2, or KARRIKIN INSENSITIVE-2) is reported to have important roles in mycorrhizal symbiosis, notably, D3, D14 and D14L are localised in the nucleus.
NOPE1 or 'NO PERCEPTION 1', is a transporter protein in Rice (Oryza sativa) and Maize (Zea mays), also required for the priming stage for colonisation by the fungus. NOPE1 is a member of Major Facilitator Super family of transport proteins, capable of N-acetylglucosamine transport. Since nope1 mutants root exudates fail to elicited transcriptional responses in fungi, it strongly seems that NOPE1 secretes something (not yet characterised) that promotes fungal response.
Perception
There are two main type of root symbiosis; one is root nodule symbiosis by Rhizobia (RN-type) and another is Arbuscular Mycorrhiza (AM-type). There are common genes involved in between these two pathways. these key common components, form the Common Symbiosis pathway (CSP or CSSP). It has been proposed that, RN symbiosis has originated from AM symbiosis. The perception of the presence of the fungal symbiont takes place mainly through fungal chemical secretions generally termed as Myc-factors. Receptors for Myc-factors are yet to be identified. However, DMI2/SYMRK probably acts as a co-receptor of Myc factor receptor (MFR). The AM fungal secreted materials relevant to symbiosis are Myc-LCOs, Myc-COs, N-Acetylglucosamine
{| class="wikitable"
|+ Fungal Myc-factors and the plant protein they act on
|-
! Myc factor!! Plant protein it mainly act on
|-
| Myc-LCOs || LYS11 in Lotus japonicus
|-
| Short chain chitin oligomers (COs) || OsCERK1 and OsCEBiP in rice
|-
| N-acetylglucosamine || NOPE-1 in maize
|-
|}
Fungal Molecules that triggers CSSP
Myc-LCOs (lipochitooligosaccharides)
Like Rhizobial LCOs (Nod factors); Myc-LCOs play important role in perception stage. They are a kind of secreted compounds from AM fungi, mainly mixtures of lipo-chito-oligosaccharides (Myc-LCOs). In Lotus japonicus, LYS11, a receptor for LCOs, was expressed in root cortex cells associated with intra-radical colonizing arbuscular mycorrhizal fungi
Short chain chitin oligomers (Myc-COs)
AM host plants show symbiotic-activated calcium waves upon exposure to short chain chitin oligomers. It has been reported that production of these molecules by the AM fungus Rhizophagus irregularis, is strongly stimulated upon exposure to strigolactones. This suggests that plants secrete strigolactones and in response, the fungus increases short chain chitin oligomers, which in turns elicits the plant response to accommodate the fungus. The lysine motif domain of OsCERK1 and OsCEBiP is thought to be involved in the perception of short chain chitin oligomers.
N-Acetylglucosamine
NOPE-1 is transporter (described above). NOPE-1 also shows a strong N-acetylglucosamine uptake activity, and is thought to be associated with recognition of presence of fungal symbiont.
Some plant proteins are suspected to recognise Myc-factors, and the rice OsCERK1 Lysin motif (LysM) receptor-like kinase, is one of them.
Cell Surface Receptors
There are multiple families of pattern recognition receptors and co-receptors involved in recognition of microbial pathogens and symbionts. Some of the relevant families involved in CSSP, are Membrane bound LysMs (LYM), Soluble LysM Receptor like Protein, LYK (LysM receptors with active Kinase domain), LYR (LysM proteins with inactive kinase domain), etc.
Seemingly, different combinations of a LYK and LYR receptors perceive and generate differential signals, such as some combinations generate a pathogen recognition signal whereas some combinations generate symbiotic signals.
Receptor-like Kinases (RLKs) DMI2/ SYMRK is a receptor-like kinase, an important protein in endosymbiosis signal perception, reported in several plants (Mt-DMI2 or Mt-NORK in Medicago trancatula; Lj-SYMRK in Lotus japonicas; Ps-SYM19 in Pisum sativum; OsSYMRK in Rice). OsSYMRK lacks an N-terminal domain and exclusively regulate AM symbiosis (is not involved in the RN symbiosis). Notably, it has been found that a Nod-factor inducible gene, MtENOD11, is activated in the presence of AMF exudates; little is known about this phenomenon.
LysM receptor-like kinase Lysin Motif (LysM) receptor-like kinase are a subfamily related to membrane bound Receptor-like kinase (RLKs) with an extracellular region consisting of 3 Lysine motifs. They have some important orthologs in different plants, that vary in their function. In some plant species they are involved in AM symbiosis, in others they are not. Tomato (Solanum lycopersicum), a non-legume eudicot, also have a similar LysM receptor, SlLYK10 that Promotes AM symbiosis. There are some co-receptors of Myc-factor receptor viz., OsCEBiP in Rice, a LysM membrane protein can function as a co-receptor of OsCERK1 but it participates in a different pathway.
Most of these kinases are serine/threonine kinases, some are tyrosine kinases. Also, they are type-1 transmembrane proteins, that indicates their N-terminal domain towards the outside of the cell, and the C-terminal domain is towards inside of the cell.
Transmission
The transmission of signal cascades into the nucleus is not well understood. However, this transmission includes carrying the message up to the nuclear membrane and generation of a calcium wave. Some elements involved in this process are:
Nucleoporins
Lotus japonicus Nucleoporins LjNUP85 and LjNUP133 has potential role in transmission of the signal. Lj-NENA is another important nucleoporin that plays role in AM symbiosis.
HMGR and Mevalonate.
It has been proposed that the enzyme 3-hydroxy-3-methylglutaryl-CoA reductase (HMG CoA reductase or HMGR) has potential role in the transmission stage. The enzyme is activated by SYMRK/DMI2, and forms mevalonate. This mevalonate acts as a second messenger, and activates a nuclear potassium channel, DMI1 or POLLUX.
Nuclear membrane cation channels.
The nuclear calcium channel CNGC15, which is cyclic nucleotide gated ion channel; mediates the symbiotic nuclear Ca2+ influx, and it is countered by K+ efflux by DMI1.
TranscriptionCalmodulin is a widespread regulatory protein that functions along with Ca2+ in various biological processes. In AM symbiosis signalling, it modulates CCaMK. CCaMK or DMI3 is a calcium-and-calmodulin-dependent kinase (CCaMK) thought to be a key decoder of Ca2+ oscillations and an important regulatory kinase protein. Nuclear Ca2+ spiking promotes binding of Ca2+ calmodulin with CCaMK. Binding of Ca2+ calmodulin with CCaMK causes conformational change of CCaMK that stimulates a target protein, CYCLOPS, which has different orthologs. CYCLOPS is a coiled coil domain containing protein possibly form a complex with CCaMK that works along with DELLA proteins. DELLA proteins are a kind of GRAS-domain protein originally identified as repressors of the Gibberellin signalling pathway, however now it is seen that DELLA participates in many signalling pathways. There are two DELLA proteins in Medicago trancatula and Pisum sativum that play a role in symbiosis whereas in rice only one DELLA protein fulfils this task. Reduced Arbuscular Mycorrhiza or RAM1 is a GRAS protein whose gene is directly regulated by DELLA and CCaMK/ CYCLOPS. By using chromatin immunoprecipitation assays, it has been shown that RAM1 binds to RAM2 gene promoter. RAM1 also regulates many of the plant genes that participate in AMF accommodation.
Some GRAS proteins play a role in AM symbiosis but these roles are not yet fully understood. These include RAM1, RAD1 (REQUIRED FOR ARBUSCLE DEVELOPMENT 1), MIG1 (MYCORRHIZA INDUCED GRAS1), NSP1 and NSP2. WRKY transcription factor genes are thought to play very important roles in establishment of mycorrhizal symbiosis and they perhaps work through regulating plant defense genes.
The Accommodation program
Root cortex cells experience important changes in order to accommodate for the fungal endosymbiont. The pre-penetration apparatus (PPA) in outer cell layers and the peri-arbuscular membrane that surrounds arbuscules in inner cell layers need to be formed and the plant cell cytoplasm needs to rearrange, the vacuole retracts in size, the nucleus and nucleolus enlarge in size and chromatin decondense indicating heightened transcriptional activity. Plastids multiply and stay connected with “stromulus”. Furthermore, it was suggested that the apoplastic longitudinal hyphal growth is probably regulated by plant genes such as taci1 and CDPK1.
Genes and proteins playing a role in the accommodation programme
Although various proteins have been identified which may play role on how this accommodation process occurs, the detailed signalling cascade is not fully understood. Some of the proteins and mechanisms involved in the deposition on peri-arbuscular membrane are EXOCYST complex, EXO70 subunit, a symbiosis-specific splice variant of SYP132, VAPYRIN, and two variants of VAMP721. Plant enzymes FatM and RAM2 and ABC transporter STR/STR2 are putatively involved in the synthesis and supplying of a lipid 16:0 β-monoacylglycerol to the AM fungi. Recently discovered kinases that regulate the AMF accommodation programm include ADK1, AMK8, AMK24, ARK1 and ARK2.
The protein composition of the peri-arbuscular membrane is very different from that of the plasma membrane. It includes some special transporters such as phosphate transporters (Mt-PT4, Os-PT11, Os-PT13) and ammonium transporters (Mt-AMT2 and 3). It also includes ABC transporters such as STR/STR2 putatively involved in lipid transport.
Evolutionary significance
AM fungi and plants co-evolved and developed a very complex interaction that allow the plant accommodate the AM-fungal host. It has been proposed that the RN symbiosis has originated from the AM symbiosis.
See also
Receptor tyrosine kinase
Serine threonine kinase
Pattern recognition receptors
Monoglyceride
Strigolactone
Plant intelligence
Cell signalling
Signal transduction
Pathogen Associated Molecular Pattern
Microbe Associated Molecular Pattern
Mutualism
Karrikin signaling
Mevalonate pathway
References
Symbiosis
Mycology
Plant communication
Soil biology | Common symbiosis signaling pathway | [
"Biology"
] | 3,715 | [
"Behavior",
"Symbiosis",
"Plants",
"Biological interactions",
"Plant communication",
"Mycology",
"Soil biology"
] |
75,118,858 | https://en.wikipedia.org/wiki/Graphs%20with%20few%20cliques | In graph theory, a class of graphs is said to have few cliques if every member of the class has a polynomial number of maximal cliques. Certain generally NP-hard computational problems are solvable in polynomial time on such classes of graphs, making graphs with few cliques of interest in computational graph theory, network analysis, and other branches of applied mathematics. Informally, a family of graphs has few cliques if the graphs do not have a large number of large clusters.
Definition
A clique of a graph is a complete subgraph, while a maximal clique is a clique that is not properly contained in another clique. One can regard a clique as a cluster of vertices, since they are by definition all connected to each other by an edge. The concept of clusters is ubiquitous in data analysis, such as on the analysis of social networks. For that reason, limiting the number of possible maximal cliques has computational ramifications for algorithms on graphs or networks.
Formally, let be a class of graphs. If for every -vertex graph in , there exists a polynomial such that has maximal cliques, then is said to be a class of graphs with few cliques.
Examples
The Turán graph has an exponential number of maximal cliques. In particular, this graph has exactly maximal cliques when , which is asymptotically greater than any polynomial function. This graph is sometimes called the Moon-Moser graph, after Moon & Moser showed in 1965 that this graph has the largest number of maximal cliques among all graphs on vertices. So the class of Turán graphs does not have few cliques.
A tree on vertices has as many maximal cliques as edges, since it contains no triangles by definition. Any tree has exactly edges, and therefore that number of maximal cliques. So the class of trees has few cliques.
A chordal graph on vertices has at most maximal cliques, so chordal graphs have few cliques.
Any planar graph on vertices has at most maximal cliques, so the class of planar graphs has few cliques.
Any -vertex graph with boxicity has maximal cliques, so the class of graphs with bounded boxicity has few cliques.
Any -vertex graph with degeneracy has at most maximal cliques whenever and , so the class of graphs with bounded degeneracy has few cliques.
Let be an intersection graph of convex polytopes in -dimensional Euclidean space whose facets are parallel to hyperplanes. Then the number of maximal cliques of is , which is polynomial in for fixed and . Therefore, the class of intersection graphs of convex polytopes in fixed-dimensional Euclidean space with a bounded number of facets has few cliques.
References
Graph theory
Discrete mathematics | Graphs with few cliques | [
"Mathematics"
] | 562 | [
"Discrete mathematics",
"Mathematical relations",
"Graph theory",
"Graphs"
] |
75,119,990 | https://en.wikipedia.org/wiki/Siwoloboff%20method | The Siwoloboff method is used to determine the boiling point of small samples of liquid chemicals. A sample in an ignition tube (also called a fusion tube) is attached to a thermometer with a rubber band, and immersed in a Thiele tube, water bath, or other suitable medium for heating. A sealed capillary, open end pointing down, is placed in the ignition tube.
The apparatus is heated. Dissolved gases evolve from the sample first, and the air in the capillary tube expands. Once the sample starts to boil, heating is stopped, and the temperature starts to fall. The temperature at which the liquid sample is sucked into the sealed capillary is the boiling point of the sample.
References
Laboratory techniques | Siwoloboff method | [
"Chemistry"
] | 153 | [
"nan"
] |
75,120,580 | https://en.wikipedia.org/wiki/HD%20152843 | HD 152843 (also designated as TOI-2319) is a single star with a pair of close-orbiting exoplanets, located in the northern constellation of Hercules. It is positioned at a distance of 356 light years from the Sun based on parallax measurements, and at that range is too faint to be viewed with the naked eye, having an apparent visual magnitude of 8.85. The system is receding further away with a radial velocity of 10 km/s.
This is a G-type main-sequence star with a stellar classification of G0. It has 1.15 times the mass and 1.43 times the girth of the Sun. Around four billion years of age, HD 152843 is a quiet star, showing very little magnetic activity in its chromosphere. The abundance of iron, a measure of the star's metallicity, is somewhat lower than in the Sun. It is spinning with a projected rotational velocity of 8.4 km/s.
Planetary system
This star has two confirmed exoplanets orbiting it, being designated HD 152843 b and HD 152843 c. Both were discovered using NASA’s Transiting Exoplanet Survey Satellite (TESS) when they were observed transiting their host star.
HD 152843 b is the closest planet to HD 152843, orbiting its host star in just 11.62 days. The planet has 9.8 Earth masses and 3.1 Earth radii. The planet orbits the star at a distance of 0.105 astronomical units (au), has an orbital eccentricity of 0.05, and has an orbital inclination of 89.3°.
HD 152843 c is the second planet in the star system and farthest planet from its star. It has 9.7 Earth masses and 5.9 Earth radii. It orbits its host star at a speed of 7.1 kilometers a second, with its orbital eccentricity being 0.07 and an orbital inclination of 89.2°. Its low density of makes it a super-puff planet.
References
G-type main-sequence stars
Planetary systems with two confirmed planets
Hercules (constellation)
BD+20 3347
152843
2319
349488688
J16550834+2029287 | HD 152843 | [
"Astronomy"
] | 474 | [
"Hercules (constellation)",
"Constellations"
] |
75,120,620 | https://en.wikipedia.org/wiki/Kinetotroph | A kinetotroph or kinetic harvester is a hypothetical organism that would use kinetic energy to produce complex molecules like adenosine triphosphate (ATP). Kinetotrophs could obtain their energy from numerous sources like wind, tides, or currents; this would allow them to inhabit locations with minimal light for photosynthesis. Kinetotrophs could descend from chemotrophs, and have been hypothesized to take the form of sedentary ciliates and reed-like organisms.
There are no known kinetotrophs on Earth, likely because the process is less efficient than other sources of energy like light or chemicals. However, similar transducer systems have been observed in some organisms. For example, some fish possess a lateral line organ, which uses cilia to turn the movement of fluid into electric signals.
Mechanisms
The theoretical mechanics that would allow kinetotrophism vary widely. One pathway proposed by Dirk Schulze-Makuch and Louis N. Irwin involves lever-like proteins that would be moved by the flow of fluid. When inside a protein channel with cilia-like proteins that could act as channel guards, the levers could allow specific molecules into or out of the cell. Harnessing the Gibbs–Donnan effect, sodium ions could be made to enter the cell and fuel a hydrogen transporter similar to those in mitochondria, thus allowing for energy-storing molecules like ATP to be synthesized. This mechanism would act like a battery; thus, only enough time and a flow of fluid in the range of millimetres per second would be required for the synthesizing of complex molecules.
Another mechanism to derive energy from kinetics would be a spring-like structure. Fluid currents or tides could place pressure on cilia structures, bending them and creating tensile energy. When the pressure subsides, that tension would be released and could create usable energy.
Habitat
It has been proposed that kinetotrophs could exist underneath the ice sheet of the Jovian moon Europa. These organisms might attach to the underside of the ice sheet, or to substrates on the ocean floor. The kinetic energy these organisms would harness could be provided by convection cells, where currents are created by the varying temperatures of fluid throughout the water column.
References
Trophic ecology
Hypothetical life forms
Kinetic energy | Kinetotroph | [
"Physics",
"Biology"
] | 471 | [
"Mechanical quantities",
"Physical quantities",
"Hypothetical life forms",
"Kinetic energy",
"Biological hypotheses"
] |
75,121,335 | https://en.wikipedia.org/wiki/Helical%20armature | A helical armature is a form of air-gap electric motor or generator armature wound in a helical fashion as opposed to a conventional random or orthocyclic winding. Such a design is of interest in superconducting motor and generation technology, though comparatively little research has been done on the subject. An important and remarkable feature of helical armature windings is that they have no end windings. Moreover, as each conductor follows a helical path of constant pitch, helical windings are not easily divided into active and end regions. An important downside, though, is that such armatures provide poor winding factors.
Use in motors
Motors of helical armature design have a lower winding resistance, allowing the motor to run more efficiently, and giving it a longer lifespan. Helical windings also provide low inertia and smooth torque for low-speed DC motors. A disadvantage is that they have relatively low winding ratios.
Use in generators
An advantage of helical armature windings in superconducting generators is that they have higher VA ratings, lower armature resistance, and lower synchronous reactance. Future superconducting generators would benefit from a helical winding because due to the absence of active and end zone it can be supported uniformly, unlike a conventional winding. There is a <10% loss in motor flux though, but this would be compensated for by the various advantages in this design.
See also
Coil winding technology
References
Electric motors
Electronics | Helical armature | [
"Technology",
"Engineering"
] | 321 | [
"Electrical engineering",
"Engines",
"Electric motors"
] |
75,122,057 | https://en.wikipedia.org/wiki/Maria%20Gatu%20Johnson | Maria Gatu Johnson (born 1978) is a Swedish-American plasma physicist whose research involves the use of neutron spectrometry to study inertial confinement fusion and stellar nucleosynthesis. She works at the Massachusetts Institute of Technology as a principal research scientist in the MIT Plasma Science and Fusion Center.
Education and career
Gatu Johnson earned a master's degree in engineering physics from Uppsala University in Sweden in 2003, and completed a Ph.D. in applied nuclear physics there in 2010. Her work there involved the application of neutron spectrometry to the Joint European Torus, a magnetic confinement fusion experiment in England.
She was a postdoctoral researcher at the MIT Plasma Science and Fusion Center from 2010 to 2013, before becoming a permanent member of the research staff there. In 2023 she was promoted to principal research scientist. At the Plasma Science and Fusion Center, she has been in charge of the Magnetic Recoil Neutron Spectrometer (MRS) beginning in 2013.
Recognition
Gatu Johnson was the 2019 recipient of the Katherine E. Weimer Award of the American Physical Society (APS), given biennially to recognize early-career research excellence by a female plasma physicist. She is a recipient of the 2022 National Nuclear Security Administration Secretary's Honor Award, and of the 2023 Department of Energy Secretary's Achievement Award.
In 2022, the Burning Plasma Team of the National Ignition Facility, including Gatu Johnson, received the John Dawson Award for Excellence in Plasma Physics Research of the APS, given "for the first laboratory demonstration of a burning deuterium-tritium plasma where alpha heating dominates the plasma energetics".
She was named a Fellow of the American Physical Society in 2023, after a nomination from the APS Division of Plasma Physics, "for pioneering efforts in the cross-cut field of plasma-nuclear science and for groundbreaking studies of macroscopic plasma flows in Inertial Confinement Fusion implosions".
References
External links
1978 births
Living people
Swedish emigrants to the United States
Swedish physicists
Swedish women physicists
American physicists
American women physicists
Plasma physicists
Uppsala University alumni
Fellows of the American Physical Society | Maria Gatu Johnson | [
"Physics"
] | 435 | [
"Plasma physicists",
"Plasma physics"
] |
75,122,285 | https://en.wikipedia.org/wiki/International%20Particle%20Physics%20Outreach%20Group | The International Particle Physics Outreach Group (IPPOG) is a network of scientists, educators, and communicators from several countries that works to improve the public's understanding and appreciation of particle physics. Established in 1997 at CERN, IPPOG works in collaboration with particle physics laboratories and experiments, including CERN, the Pierre Auger Observatory, DESY, and GSI.
History
IPPOG started out as the European Particle Physics Outreach Group (EPPOG) in 1997 with the sponsorship of the European Committee for Future Accelerators (ECFA) and the High Energy Particle Physics Board of the European Physical Society (EPS-HEPP).
In November 2012, EPPOG became IPPOG and soon after added the US as its first country member, followed by Israel, Ireland, Slovenia, Australia and South Africa.
Activities
IPPOG focuses on creating and implementing outreach initiatives related to particle physics. These include exhibitions, educational materials, and events designed for various audiences. Additionally, IPPOG provides resources for science communicators, educators, and physicists to assist in their outreach efforts, aiming to convey the concepts of particle physics in a comprehensible manner.
References
External links
Physics education
CERN
Particle physics
1997 establishments in Switzerland | International Particle Physics Outreach Group | [
"Physics"
] | 256 | [
"Applied and interdisciplinary physics",
"Physics education",
"Particle physics"
] |
75,122,299 | https://en.wikipedia.org/wiki/275%20%28number%29 | 275 (two hundred [and] seventy-five) is the natural number following 274 and preceding 276.
In mathematics
275 is an odd composite number with 2 prime factors.
275 is equivalent to the number of partitions of 28 when no partition occurs only once. Partitions are the number of ways of writing a number as a sum of other positive integers.
275 is the sum of fifth powers of the first two primes (2^5 + 3^5 = 275).
275 is the maximum number of pieces made by cutting an annulus with 22 cuts.
275 is the smallest non semiprime that follows the equations n>1 and the greatest common denominator of n and b^n-b is 1 for some value of b.
References
Integers | 275 (number) | [
"Mathematics"
] | 155 | [
"Elementary mathematics",
"Integers",
"Mathematical objects",
"Numbers"
] |
75,122,486 | https://en.wikipedia.org/wiki/Monotone%20dualization | In theoretical computer science, monotone dualization is a computational problem of constructing the dual of a monotone Boolean function. Equivalent problems can also be formulated as constructing the transversal hypergraph of a given hypergraph, of listing all minimal hitting sets of a family of sets, or of listing all minimal set covers of a family of sets. These problems can be solved in quasi-polynomial time in the combined size of its input and output, but whether they can be solved in polynomial time is an open problem.
Definitions
A Boolean function takes as input an assignment of truth values to its arguments, and produces as output another truth value. It is monotone when changing an argument from false to true cannot change the output from true to false. Every monotone Boolean function can be expressed as a Boolean expression using only logical disjunction ("or") and logical conjunction ("and"), without using logical negation ("not"). Such an expression is called a monotone Boolean expression. Every monotone Boolean expression describes a monotone Boolean function.
There may be many different expressions for the same function. Among them are two special expressions, the conjunctive normal form and disjunctive normal form. For monotone functions these two special forms can also be restricted to be monotone:
The conjunctive normal form of a monotone function expresses the function as a conjunction ("and") of clauses, each of which is a disjunction ("or") of some of the variables. A clause may appear in the conjunctive normal form if it is true whenever the overall function is true; in this case it is called an implicate, because the truth of the function implies the truth of the clause. This expression may be made canonical by restricting it to use only prime implicates, the implicates that use a minimal set of variables. The conjunctive normal form using only prime implicates is called the prime CNF.
The disjunctive normal form of a monotone function expresses the function as a disjunction ("or") of clauses, each of which is a conjunction ("and") of variables. A conjunction may appear in the disjunctive normal form if it is false whenever the overall function is false; in this case, it is called an implicant, because its truth implies the truth of the function. This expression may be made canonical by restricting it to use only prime implicants, the implicants that use a minimal set of variables. The disjunctive normal form using only prime implicants is called the prime DNF.
The dual of a Boolean function is obtained by negating all of its variables, applying the function, and then negating the result. The dual of the dual of any Boolean function is the original function. The dual of a monotone function is monotone. If one is given a monotone Boolean expression, then replacing all conjunctions by disjunctions produces another monotone Boolean expression for the dual function, following De Morgan's laws. However, this will transform the conjunctive normal form into disjunctive normal form, and vice versa, which may be undesired. Monotone dualization is the problem of finding an expression for the dual function without changing the form of the expression, or equivalently of converting a function in one normal form into the dual form.
As a functional problem, monotone dualization can be expressed in the following equivalent ways:
Given a (prime) CNF expression, construct a (prime) CNF expression for the dual function.
Convert the (prime) CNF expression of a function into the (prime) DNF expression for the same function, or vice versa
Construct the transversal hypergraph of a given hypergraph. This is a hypergraph on the same vertex set that has a hyperedge for every minimal subset of vertices that touches all edges of the given hypergraph.
Given a family of sets, generate all minimal hitting sets of the family. These are sets of elements that include at least one element from each set, and have no proper subset with the same property. If the sets in the given family are interpreted as hyperedges in a hypergraph, their minimal hitting sets are the hyperedges of the transversal hypergraph.
Given a family of sets, generate all minimal set covers of the family. A set cover is a subfamily with the same union as the whole family. If the sets in the given family are interpreted as vertices in a hypergraph, with each element of the sets interpreted as a hyperedge incident to the sets containing that element, then the minimal set covers are the hyperedges of the transversal hypergraph.
Another version of the problem can be formulated as a problem of "exact learning" in computational learning theory: given access to a subroutine for evaluating a monotone Boolean function, reconstruct both the CNF and DNF representations of the function, using a small number of function evaluations. However, it is crucial in analyzing the complexity of this problem that both the CNF and DNF representations are output. If only the CNF representation of an unknown monotone function is output, it follows from information theory that the number of function evaluations must sometimes be exponential in the combined input and output sizes. This is because (to be sure of getting the correct answer) the algorithm must evaluate the function at least once for each prime implicate and at least once for each prime implicant, but this number of evaluations can be exponentially larger than the number of prime implicates alone.
It is also possible to express a variant of the monotone dualization problem as a decision problem, with a Boolean answer:
Test whether two prime CNF expressions represent dual functions
Test whether a prime CNF expression and a prime DNF expression represent the same function.
It is an open problem whether monotone dualization has a polynomial time algorithm (in any of these equivalent forms). The fastest algorithms known run in quasi-polynomial time.
The size of the output of the dualization and exact learning problems can be exponentially large, as a function of the number of variables or the input size. For instance, an -vertex graph consisting of disjoint triangles has hyperedges in its transversal hypergraph. Therefore, what is desired for these problems is an output-sensitive algorithm, one that takes a small amount of time per output clause. The decision, dualization, and exact learning formulations of the problem are all computationally equivalent, in the following sense: any one of them can be solved using a subroutine for any other of these problems, with a number of subroutine calls that is polynomial in the combined input and output sizes of the problems. Therefore, if any one of these problems could be solved in polynomial time, they all could. However, the best time bound that is known for these problems is quasi-polynomial time. It remains an open problem whether they can be solved in polynomial time.
Computational complexity
Equivalence of decision, enumeration, and exact learning
The problem of finding the prime CNF expression for the dual function of a monotone function, given as a CNF formula, can be solved by finding the DNF expression for the given function and then dualizing it. Therefore, finding the dual CNF expression, and finding the DNF expression for the (primal) given function, have the same complexity.
This problem can also be seen as a special case of the exact learning formulation of the problem. From a given CNF expression, it is straightforward to evaluate the function that it expresses. An exact learning algorithm will return both the starting CNF expression and the desired DNF expression. Therefore, dualization can be no harder than exact learning.
It is also straightforward to solve the decision problem given an algorithm for dualization: dualize the given CNF expression and then test whether it is equal to the given DNF expression. Therefore, research in this area has focused on the other direction of this equivalence: solving the exact learning problem (or the dualization problem) given a subroutine for the decision problem.
outline the following algorithm for solving exact learning using a decision subroutine:
Initialize sets of the prime CNF and prime DNF clauses that have been identified so far, initially empty.
Repeat the following steps:
Use the decision problem to test whether the current sets of prime CNF and prime DNF clauses are dual, and if so terminate the algorithm, returning the clauses that have been found.
Construct a truth assignment to the variables for which the function value is neither forced to be true by the known prime DNF clauses, nor forced to be false by the known prime CNF clauses. This construction may be performed by choosing values for the variables one at a time, at each step using the decision problem to preserve the property that the CNF and DNF clauses are non-dual when restricted to the chosen truth assignment.
Evaluate the function at this truth assignment. If it is true, then try changing variables one at a time from true to false to find a minimal truth assignment for which the function still evaluates as true. This minimal truth assignment corresponds to a prime DNF clause, not already known; add this to the set of known clauses.
Symmetrically, if the function evaluates to false, then try changing variables one at a time from false to true to find a maximal truth assignment for which the function still evaluates as false. This maximal truth assignment corresponds to a prime CNF clause, not already known; add this to the set of known clauses.
Each iteration through the outer loop of the algorithm uses a linear number of calls to the decision problem to find the unforced truth assignment, uses a linear number of function evaluations to find a minimal true or maximal false function value, and adds one clause to the output. Therefore, the total number of calls to the decision problem and the total number of function evaluations is a polynomial of the total output size.
Quasi-polynomial time
A central result in the study of this problem, by Michael Fredman and Leonid Khachiyan, is that monotone dualization (in any of its equivalent forms) can be solved in quasi-polynomial time. Their algorithms directly solve the decision problem, but can be converted to the other forms of the monotone dualization problem as described in . Alternatively, in cases where the answer to the decision problem is no, the algorithms can be modified to return a witness, that is, a truth assignment for which the input formulas fail to determine the function value. Its main idea is to first "clean" the decision problem instance, by removing redundant information and directly solving certain easy-to-solve cases of the problem. Then, in remaining cases it branches on a carefully chosen variable. This means recursively calling the same algorithm on two smaller subproblems, one for a restricted monotone function for which the variable has been set to true and the other in which the variable has been set to false. The cleaning step ensures the existence of a variable that belongs to many clauses, causing a significant reduction in the recursive subproblem size.
In more detail, the first and slower of the two algorithms of Fredman and Khachiyan performs the following steps:
Remove any clause that is not minimal among the given set of clauses. (That is, the removed clause uses a set of variables that is a superset of the variables in another clause of the same type.)
If the two sets of clauses (CNF and DNF in one version of the decision problem, or sets of CNF clauses that are supposed to represent two dual functions in another version) do not cover the same sets of variables, return that they are not dual.
If two clauses from different sets of clauses use disjoint sets of variables, return that they are not dual. In this case, the clauses imply contradictory function values for any truth assignment that is consistent with both of them.
If any clause in one class uses a number of variables that is larger than the number of clauses in the other class, return that they are not dual. If this clauses is to be minimal, it cannot be the case that removing any one variable from it produces a valid clause for the same function, but there are not enough clauses from the other class to block each of these removals.
For each clause, count the number of truth assignments whose function value is determined by the clause. This number is , for a clause with variables in a problem with variables. If the sum of these numbers, added over all clauses of both types, is fewer than the truth assignments that exist in total, then return that the two sets of clauses are not dual: at least one truth assignment must have a value that they do not determine.
If either set of clauses is empty, or both consist of only one clause, handle the problem as a special case in constant time.
In the remaining cases there exists a variable which occurs in a large fraction of one of the two sets of clauses. Branch on that variable. More precisely, if there are total clauses, then (to cover all of the truth assignments) at least one of the clauses must have at most variables. Each clause in the other set of clauses must have a non-empty intersection with this short clause, so one of the variables in the short clause occurs in at least a fraction of the other set of clauses.
When this algorithm branches on a variable occurring in many clauses, these clauses are eliminated from one of the two recursive calls. Using this fact, the running time of the algorithm can be bounded by an exponential function of .
A second algorithm of Fredman and Khachiyan has a similar overall structure, but in the case where the branch variable occurs in many clauses of one set and few of the other, it chooses the first of the two recursive calls to be the one where setting the branch variable significantly reduces the number of clauses. If that recursive call fails to find an inconsistency, then, instead of performing a single recursive call for the other branch, it performs one call for each clause that contains the branch variable, on a restricted subproblem in which all the other variables of that clause have been assigned in the same way. Its running time is an exponential function of .
Polynomial special cases
Many special cases of the monotone dualization problem have been shown to be solvable in polynomial time through the analysis of their parameterized complexity. These include:
Dualization of CNF or DNF formulas in which each variable appears in a bounded number of clauses, or exact learning of monotone functions that have formulas of this type.
Constructing transversal hypergraphs of uniformly sparse hypergraphs, in which every induced sub-hypergraph has bounded average degree, and of hypergraphs for which generalizations of the graph-theoretic concepts of treewidth or degeneracy are bounded.
Constructing transversal hypergraphs for which the complement (the hypergraph obtained by complementing each hyperedge) has low degree.
Applications
One application of monotone dualization involves group testing for fault detection and isolation in the model-based diagnosis of complex systems. From a collection of observations of faulty behavior of a system, each with some set of active components, one can surmise that the faulty components causing this misbehavior are likely to form a minimal hitting set of this family of sets.
In biochemical engineering, the enumeration of hitting sets has been used to identify subsets of metabolic reactions whose removal from a system adjusts the balance of the system in a desired direction. Analogous methods have also been applied to other biological interaction networks, for instance in the design of microarray experiments that can be used to infer protein interactions in biological systems.
In recreational mathematics, in the design of sudoku puzzles, the problem of designing a system of clues that has a given grid of numbers as its unique solution can be formulated as a minimal hitting set problem. The 81 candidate clues from the given grid are the elements to be selected in the hitting set, and the sets to be hit are the sets of candidate clues that can eliminate each alternative solution. Thus, the enumeration of minimal hitting sets can be used to find all systems of clues that have a given solution. This approach has been as part of a computational proof that it is not possible to design a valid sudoku puzzle with only 16 clues.
References
Computational problems
Families of sets
Hypergraphs
Covering problems
Quasi-polynomial time algorithms | Monotone dualization | [
"Mathematics"
] | 3,411 | [
"Computational problems",
"Combinatorics",
"Families of sets",
"Basic concepts in set theory",
"Mathematical problems"
] |
75,123,579 | https://en.wikipedia.org/wiki/James%20A.%20Shayman | James Alan Shayman is an American physician scientist, nephrologist, and pharmacologist. He is Professor of Internal Medicine and Pharmacology and the Agnes C. And Frank D. McKay Professor at the Medical School of the University of Michigan. He also serves as a staff nephrologist at the Ann Arbor Veterans Administration Medical Center.
Shayman's research interests span the study of lysosomal biology and related disorders. His group is most known for the development of small-molecule inhibitors of glycosphingolipid synthesis and their use in lysosomal glycosphingolipid storage disorders. His team also discovered and characterized a novel lysosomal phospholipase A2, PLA2G15 and is investigating its role in phospholipidosis. He has published over 160 articles.
Shayman is a Fellow of the American Heart Association and American Society of Nephrology as well as a Life Fellow of Clare Hall at the University of Cambridge. He has served as an Associate Editor for the Journal of Clinical Investigation and Translational Research and is serving in the same role for the Journal of the American Society of Nephrology.
Education and early career
Shayman obtained a Bachelor of Arts degree from Cornell University in 1976, and received an M.D. in 1980 from Washington University in St. Louis. From July 1980 to June 1983, he served as a house officer in Medicine at Barnes Hospital in St. Louis, Missouri. Beginning in 1983, he pursued a Postdoctoral Fellowship with a specialization in Nephrology and Pharmacology under the mentorship of Aubrey Morrison and Oliver H. Lowry at Washington University School of Medicine in St. Louis.
Career
Following his post-doctoral fellowship training, in 1985, Shayman began his academic career as an instructor in the Renal department of Washington University School of Medicine. He was recruited to the University of Michigan where from 1986 to 1992 he was appointed as assistant professor in the Department of Internal Medicine, Division of Nephrology. He subsequently was promoted to the positions of associate professor in 1992 and professor in 1997, respectively with a secondary appointment in Pharmacology. He has been serving as the Agnes C. and Frank D. McKay Professor.
Shayman was the Associate Chair for Research Programs at the Department of Internal Medicine and Associate Vice President for Research in Health Sciences of the University of Michigan. In addition, he has been serving as a staff nephrologist Veterans Administration Medical Center in Michigan.
Research
Shayman's research is focused on lysosomal biology, the pathophysiology of traditional lysosomal storage disorders, and the role of the lysosome in more prevalent diseases including diabetes mellitus and polycystic kidney disease. A particular emphasis has been on the development of drug therapeutics for disorders of glycosphingolipid metabolism. This work has resulted in several patents including "Amino ceramide-like compounds and therapeutic methods of use" and "Pyridine inhibitors of glucosylceramide synthase and therapeutic methods using the same."
Substrate reduction therapy
An early collaboration with Norman Radin focused on substrate reduction as an alternative to enzyme replacement therapy for the treatment of lysosomal disorders such as Gaucher disease. It was suggested that substrate reduction posits that inhibition of metabolites that accumulate in the lysosome due to the loss of activity of a specific hydrolase can be treated with reversible inhibitors of specific anabolic enzymes. Following an early collaboration with Radin, the Shayman group went on to develop inhibitors of glucosylceramide synthase followed by proof of concept studies in models of Gaucher and Fabry disease that experimentally established the viability substrate reduction therapy. Although this concept was initially met with skepticism from the academic and pharmaceutical communities, these compounds were eventually licensed to the Genzyme Corporation for clinical development in 2000. In 2014 eliglustat tartrate was approved by the Food and Drug Administration and the European Medicines Association. Eliglustat tartrate was the first orally bioavailable agent approved as the first stand-alone substrate reduction therapy for Gaucher disease type 1.
Glycosphingolipid synthesis inhibitor
Shayman's work on developing the "first in class" glycosphingolipid synthesis inhibitor led to the consideration of whether more common disorders might be amenable to targeting glucosylceramide synthase. Based on fundamental studies by his group and others demonstrating a role for glucosylceramide metabolism in conditions associated with aerobic glycolysis, including diabetes and polycystic kidney disease, glucosylceramide synthase inhibitors have been the focus of preclinical and clinical studies evaluating the potential for extended use applications of eliglustat and related compounds.
Brain penetrant glycolipid synthesis inhibitors
In collaboration with Scott D. Larsen, Shayman's work has also been directed toward the identification of brain-penetrant glycolipid synthesis inhibitors for the treatment of Gaucher disease types 2 and 3, GM2 gangliosidoses including Tay-Sachs and Sandhoff disease, and GM1 gangliosidosis. Using computational analysis comparing eliglustat to known CNS penetrant compounds, novel glucosylceramide synthase inhibitors were designed around the eliglustat pharmacophore, demonstrating the lower glucosylceramide and ganglioside levels within the brain.
Vasculopathy of fabry disease
The Shayman group has worked on the elucidation of the mechanisms underlying the vasculopathy of Fabry disease. His initial work led to the identification of three inducible models of vascular disease in the alpha-galactosidase A knockout mouse. These models included oxidant-induced arterial thrombosis, accelerated atherogenesis, and impaired arterial relaxation. Both decreased nitric oxide bioavailability and endothelial nitric oxide synthase uncoupling have been demonstrated to underlie these abnormalities. The insights led to identifying 3-nitrotyrosine as a biomarker for endothelial dysfunction in both experimental models and patients affected by classic forms of Fabry disease.
PLA2GXV
Attempts to delineate potential off-target effects of eliglustat led to the discovery of a novel lysosomal hydrolase, phospholipase A2 group XV (PLA2GXV). This enzyme was initially identified as a transacylase and named 1-O-acylceramide synthase. PLA2GXV is 50 percent identical to LCAT. In collaboration with John Tesmer and colleagues, the structure of PLA2GXV and, by extension, of lecithin cholesterol acyltransferase (LCAT) were solved. Mice engineered to be deficient in PLA2GXV developed a pulmonary phenotype associated with the conversion of alveolar macrophages to foam cells, a phenotype that resembles amiodarone toxicity. A 2021 work has also identified PLA2GXV as the site of action for many drugs that cause a form of toxicity termed phospholipidosis.
Awards and honors
1991 – Henry Christian Award, American Federation for Clinical Research
1994 – Elected Member, American Society for Clinical Investigation
2000 – Elected Member, Association of American Physicians
2001 – Fellow, American Heart Association
2003 – Fellow, American Society of Nephrology
2016 – Distinguished University Innovator Award, University of Michigan
2020 – Life Fellow, Clare Hall, University of Cambridge
Bibliography
Selected books
Renal Pathophysiology (1995) ISBN 978-0397513727
Essentials of Internal Medicine (2000) ISBN 978-0781719377
Selected articles
Rani CS, Abe A, Chang Y, Rosenzweig N, Saltiel AR, Radin NS, and Shayman JA. Cell cycle arrest induced by an inhibitor of glucosylceramide synthase. Correlation with cyclin-dependent kinases. J Biol Chem. 1995;270(6):2859-67.
Abe A, Shayman JA, and Radin NS. A novel enzyme that catalyzes the esterification of N-acetylsphingosine. Metabolism of C2-ceramides. J Biol Chem. 1996;271(24):14383-9.
Abe A, and Shayman JA. Purification and characterization of 1-O-acylceramide synthase, a novel phospholipase A2 with transacylase activity. J Biol Chem. 1998;273(14):8467-74.
Lee L, Abe A, and Shayman JA. Improved inhibitors of glucosylceramide synthase. J Biol Chem. 1999;274(21):14662-9.
Abe A, Gregory S, Lee L, Killen PD, Brady RO, Kulkarni A, and Shayman JA. Reduction of globotriaosylceramide in Fabry disease mice by substrate deprivation. J Clin Invest. 2000;105(11):1563-71.
Hiraoka M, Abe A, and Shayman JA. Cloning and characterization of a lysosomal phospholipase A2, 1-O-acylceramide synthase. J Biol Chem. 2002;277(12):10090-9.
Eitzman DT, Bodary PF, Shen Y, Khairallah CG, Wild SR, Abe A, Shaffer-Hartman J, and Shayman JA. Fabry disease in mice is associated with age-dependent susceptibility to vascular thrombosis. J Am Soc Nephrol. 2003;14(2):298-302.
Hiraoka M, Abe A, and Shayman JA. Structure and function of lysosomal phospholipase A2: identification of the catalytic triad and the role of cysteine residues. J Lipid Res. 2005;46(11):2441-7.
Abe A, Hiraoka M, and Shayman JA. A role for lysosomal phospholipase A2 in drug induced phospholipidosis. Drug Metab Lett. 2007;1(1):49-53.
Shayman JA. ELIGLUSTAT TARTRATE: Glucosylceramide Synthase Inhibitor Treatment of Type 1 Gaucher Disease. Drugs Future. 2010;35(8):613-20.
Shayman JA, Kelly R, Kollmeyer J, He Y, and Abe A. Group XV phospholipase A(2), a lysosomal phospholipase A(2). Prog Lipid Res. 2011;50(1):1-13.
Glukhova A, Hinkovska-Galcheva V, Kelly R, Abe A, Shayman JA, and Tesmer JJ. Structure and function of lysosomal phospholipase A2 and lecithin:cholesterol acyltransferase. Nat Commun. 2015;6:6250.
Hinkovska-Galcheva V, Treadwell T, Shillingford JM, Lee A, Abe A, Tesmer JJG, et al. Inhibition of lysosomal phospholipase A2 predicts drug-induced phospholipidosis. J Lipid Res. 2021;62:100089.
Wilson MW, Shu L, Hinkovska-Galcheva V, Jin Y, Rajeswaran W, Abe A, et al. Optimization of Eliglustat-Based Glucosylceramide Synthase Inhibitors as Substrate Reduction Therapy for Gaucher Disease Type 3. ACS Chem Neurosci. 2020;11(20):3464-73.
References
Physician-scientists
Nephrologists
American nephrologists
Pharmacologists
American pharmacologists
Cornell University alumni
Washington University School of Medicine alumni
University of Michigan faculty
Year of birth missing (living people)
Living people
Washington University School of Medicine faculty | James A. Shayman | [
"Chemistry"
] | 2,540 | [
"Pharmacology",
"Biochemists",
"Pharmacologists"
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75,123,813 | https://en.wikipedia.org/wiki/Social%20buffering | In social psychology, social buffering is a phenomenon where social connections can alleviate negative consequences of stressful events.
Although there are other models and theories to describe how social support can help reduce individuals' stress responses, social buffering hypothesis is one of the dominant ones. According to this idea, social partners, who can be familiar others or conspecifics, act as buffers in the face of stressful events, specifically while the stress is happening. The model further describes that social support is especially beneficial when levels of stress are also high, but buffering effects are not as relevant when levels of stress are low.
Social buffering has been explored in humans and other social animals, and is important to questions about physical and mental health. Research has attempted to gain insight about the protective effects of social support in several domains, such as biological, developmental, neurological, and clinical settings. Social buffering is also relevant to other psychological processes, including fear, social bonding, and emotional reactivity.
Background
Early history
Psychological research in the mid-twentieth century began to increasingly reveal the role of stressful life events on psychological well-being. This was also around the time that there was a focus on creating standardized approach to diagnosing mental illnesses, with the first Diagnostic and Statistical Manual of Mental Disorders (commonly referred to as the DSM) being published in 1952. With a honed focus on effective, universal ways to measure mental well-being, and the application of experimental psychology on social issues, a large literature on the effects of social support began to form. This occurred in an effort to fill in the gaps on the specific factors that mediate the relationship between life events and psychological consequences.
Specific focus on the attenuation of social support on the negative impacts of stressful events on physical and mental health began in the mid-1970s. This is around the time when the idea of social buffering began to take shape.
It is unclear where the phrase social buffering hypothesis was first mentioned, but one of the most credited and cited works on the topic was published by researchers Sheldon Cohen and Thomas A. Wills in 1985.
Social buffering has been an important feature in psychology since its early use, specifically relevant to social and health psychology. The framework has been applied to several other areas as well, and methods of measurement and definitions of relevant terminology continue to be refined and built upon.
Social support
Social buffering is a subset of social support, and not all occurrences of social support are social buffering. Social support encompasses both the expectation and actual act of being assisted, nurtured, attended to, or participation in a social network.
Research on social support makes the distinction between perceived support and received social support. Perceived social support refers to the amount of support people believe that they could potentially receive from their available support system, while received social support is the level of support that people have received. Some studies have shown that perceived social support may be better for mitigating the negative effects of stress on health and psychological well-being, suggesting there is a measurable difference between the types of social support, and proper definition of variables is important to research in the area.
Social support is robustly associated with positive health outcomes. Research has shown that people with larger social networks, higher-quality relationships, and greater access to social support resources have better mental and physical health. The effects of social support have been studied in many different domains of psychology, such as social, developmental, clinical, and health psychology, as well as neuroscience.
Competing model: direct effects hypothesis
The social buffering hypothesis is often compared to or evaluated with the direct effect hypothesis. This hypothesis differs from social buffering in that it holds that social support enhances physical and psychological well-being in general, regardless of the presence of stressors. This model says that social support is beneficial all the time, and that people with high social support have overall better health than those without it.
The two models tend to deal with different measures of social support. The direct effects hypothesis measures the level at which a person is integrated into a social network, while the social buffering hypothesis assesses how available the social resources are that help people respond to stressful events. The language around both hypotheses also tends to be different, with the direct effects hypothesis often looking at the enhancement of health and well-being as a result of the perception of support and integration in a network, whereas the buffering hypothesis is more concerned with protection (or prevention), especially in times of need.
Statistically, the direct effect hypothesis holds that there is no interaction between stress and social support, meaning the same beneficial effects will be observed notwithstanding of the level of stress. Conversely, according to the social buffering hypothesis, the magnitude of the beneficial effect from social support is larger when stress is present, which is reflected in a statistically significant observable interaction when the two effects are studied experimentally. This also means that knowledge of the degree of stress is required for the social buffering hypothesis, where this level may not be as relevant in the context of the direct effects hypothesis.
Despite these models providing somewhat separate explanations, research has found support for both hypotheses, and some work even suggests that both processes happen simultaneously. Researchers have suggested that work directed at critically comparing the two hypotheses may not actually benefit the field studying social support. Instead, it may be more beneficial to use either one as a model that aims to explain specific questions about how social support relates to mediators of health that can be behavioral, psychological, emotional, or biological.
Biology
Research studies done on social buffering and health consequences consistently show that the HPA axis plays a central role in the link between the two.
The hypothalamic–pituitary–adrenal (HPA) axis is a crucial regulator of neuroendocrine responses in the body. The HPA axis is made up of a series of pathways and feedback loops that involve the hypothalamus, anterior pituitary gland, and adrenal gland. It modulates several physiological processes, including the autonomic nervous system, immune system reactions, metabolism, and several other processes that are active during short-term physiological responses to stress. The HPA axis also plays a major role in bodily homeostasis, which includes regulating the cardiovascular system, reproductive system, and central nervous system in addition to those previously mentioned.
Proper functioning of the HPA axis is very important for adaptation and development, and both over- and under-reactivity can lead to a series of consequences. It is important for humans to experience high levels of circulating stress hormones early in life so that they can learn to effectively respond to threat and adapt to their environments. However, too much stress in childhood can lead to long-term and often irreversible dysfunction of the HPA axis.
HPA axis activity goes up during aversive or arousing situations, which can be induced by physical or psychosocial events. The HPA axis is particularly sensitive to psychological stressors, including uncertainty, novelty, and the feeling of being out of control. In addition to being influenced by psychological stressors, one of the most powerful and widely studied moderators of HPA axis activity induced by stressful events is social support. This is why the HPA axis is often a focal point in physiological research examining social buffering effects.
The biological mechanisms of social buffering have been explored, and several components have been identified as relevant:
Endocrine
There are several hormones involved in HPA axis endocrine regulation. One is corticotrophin-releasing factor (CRF). CRF stimulates the release of adrenocorticotropic hormone (ACTH), which is the crucial physiological regulator of increased activity of the HPA axis. Another is vasopressin (AVP), and glucocorticoids are the final step in the process. Social buffering is observed when high levels of social support are correlated with lower levels of stress hormone and HPA axis activation.
Oxytocin
Oxytocin has been recognized as an important hormone involved in the mechanism of social buffering. Oxytocin is a molecule that is often called the "love hormone". It is released into the blood in response to physiological and psychological stress, and increased oxytocin release from the hypothalamus inhibits activation of the HPA axis. Oxytocin is involved in stress processes by inhibiting the release of corticosteroids, ACTH release from the pituitary gland, and release of CRF from the hypothalamus. The central nervous system also meditates the inhibitory effect of oxytocin on the HPA axis. Oxytocin is also involved in the behavioral side of social buffering. Oxytocin's role in bonding means that it is related to the process of social support, in addition to being released in response to a stressor.
Opioids
Endogenous opioids, or endorphins, also appear to play a major role in social buffering, via a reinforcing effect that is active in social attachment. Opioid release is also observed when animals recognize each other, which supports the idea that animals find social support in others of the same species. This is necessary to see social buffering effects in animals, and opioid release also helps explain the seeking of affiliation in animals as well. Opioid release as a result of social stimulation has also been found to reduce corticotrophin-releasing factor activity in the brain and body.
Neural circuitry
Research on the brain regions involved in social buffering is less extensive compared to the role of the HPA axis and cortisol.
However, the prefrontal cortex has been identified as a region involved in the social buffering and stress responses. Higher activity in the prefrontal cortex has been found to be correlated with higher degrees of cortisol responses to stress. A similar relationship has been observed in the anterior cingulate cortex. Both the prefrontal cortex and anterior cingulate cortex have been shown to be involved in emotional responses and reactivity to stressful situations, and activity in these areas is closely related with HPA activation. The presence of social support causes cortisol levels to go down as well as decreased activity in these regions.
Social buffering has also been observed in regions that are thought to be involved in responding to threats to safety, which include the ventromedial prefrontal cortex, anterior cingulate cortex, posterior insula, and posterior cingulate cortex.
Clinical applications
Social support has been historically identified as very important for people's well-being, and it can be even more important for populations that are vulnerable to high stress and loneliness. Work on the social buffering hypothesis has been done on these populations, which include racial and ethnic minorities, sexual minorities, middle-aged and elderly, impoverished individuals, and other adversely affected demographic groups. This type of work aims to find specific applications of social buffering, often to provide frameworks for developing or assessing effectiveness of treatments or to build an understanding for prevention of the negative consequences of stressful life events.
A social buffering effect was observed in work done on suicidality, and findings indicate that focusing on buffering has the potential of being an effective area in developing interventions. The buffering effect has also been found to be strong in individuals with depression, meaning that social support can reduce symptoms of depression during times of stress. A relationship has also been drawn between social buffering and drug and alcohol use disorders, which lower likelihood of developing substance abuse disorders with higher social support.
Another issue that social buffering relates to is loneliness. The United States has a growing rate of loneliness, considered by some to be a "loneliness epidemic", and there is a documented rise in the number of people living alone in many cultures globally. Loneliness is strongly linked with many psychiatric disorders, including depression and anxiety, as well as several physical disorders, such as cardiovascular diseases and hypertension. Additionally, the rate of loneliness increases with age and has serious health consequences particularly in older populations. Research shows that high levels of social connectedness can help alleviate negative effects of loneliness that frequently accompany getting older. The robust connection between loneliness and poor mental and physical health is difficult to debate, and social buffering research can highlight the specific aspects of loneliness that are most damaging.
Social buffering is also relevant to the process of acculturation. Immigrants, guest workers, and international students may experience increased likelihood of isolation and psychological difficulties such as depressive symptoms. Research shows that those who have more interpersonal connections and participate in acculturation at higher degrees, benefit from the effects of social buffering. Increasing the size of one's social network has been shown to have salient buffering effects, particularly in older immigrants.
It Is important to note that social buffering works differently in different groups in society. There are gender, age, and cultural differences. Additionally, it can be difficult to study the effects of social support on stress in individuals who have impaired social functioning. These include individuals with social phobias and social anxiety disorder as well as autistic people.
Development
Social buffering is recognized as an essential way through which the nature of experiences in childhood affect development and subsequent health.
During infancy, parents play a large role in regulating the negative consequences of childhood, especially regarding fear or pain responses. Attachment is also very relevant to studies on development and stress reduction. Attachment theory posits that the type of attachment relationship a child forms with their parents influences their ability to regulate emotional states whether or not the parents are immediately present. Stress buffering effects are often seen with securely attached children, indicating that the type and stability of relationships is crucial to how well a child recovers from stressful events.
Some research shows that parents are especially important for social buffering up until around puberty or late childhood, when primary caregivers tend to become less influential than peers in social settings. This does not take away from the role that parents play in social buffering as a whole, and instead reflects how they are replaced by friends who become a major source of social support with buffering. Furthermore, major stressors during adolescence and puberty tend to be peers and social standing, so the social buffering provided by friends during this time is heavily interwoven with social networks and relates to an idea called the friendship protection hypothesis. The friendship protection hypothesis reflects the idea of the social buffering hypothesis and explains how children with at least one supportive friend are less negatively affected by bullying and peer rejection.
When looking at social buffering and development, a common approach to measuring stress responses involves looking at the HPA axis. The HPA axis is referred to as one of the primary hormonal stress systems. Research looking at stress and social buffering in development consistently shows that parents play a role in shaping HPA axis function, which is evidenced in part by how early social deprivation may later result in long-term dysfunction of stress reactivity. Social buffering effects have also been observed when a child is exposed to a threatening event. The presence of a parent during such a time can lower or completely block the activation of the HPA axis.
Additional support for the social buffering hypothesis and social neuroscience involves fear conditioning. The amygdala has been recognized as an important part in the process of fear learning, and research has shown that children have reduced amygdala activity when around a parent. In addition to this, greater connectivity between the prefrontal cortex and amygdala was observed when a child viewed their mother compared to a stranger. The prefrontal cortex is involved in emotional processes, so communication between the two brain areas indicates that parents play a large role in emotional regulation and provide neurological support for social buffering.
Although the functioning of stress processes and fear learning are evolutionarily crucial, research on social buffering shows that social support can reduce the negative developmental consequences of too high stress and potentially aid with proper biological functioning.
Animal research
Phenomena consistent with the social buffering hypothesis have been widely observed in non-human animals. The literature on animals uses the word conspecifics to refer to animals of the same species, and in each case it is clear that the effects are seen between like-animals and not due to the presence of other beings in general.
Social interaction and communication are very important for survival in many species of animals, aiding with cooperation and essential for protection from threats. Highly social animals, such as non-human primates, rodents, and birds, show positive physiological and psychological effects when they are together with animals of the same species. This was an idea that gained more attention in the early 2000s, while many of the experiments conducted in earlier research focused on the stress-inducing factors of social interaction.
Social buffering has been observed in a wide range of animals, including guinea pigs, horses, rhesus monkeys, and pigs. Studies have found support for social buffering both from a physiological, in the form of reduced HPA activity or lower cortisol levels, and behavioral perspective. Behavioral observations in rats, for example, include increased locomotor activity, indicating less fear, in a stress inducing open space in the presence of other rats, and an increase in the seeking of the proximity of other rats when they were exposed to stress.
Research on animals has also revealed several sensory cues for social buffering:
Olfactory cues – Highly social animals use chemical communication to transmit certain information, such as emotional status in times of stress that alters both the physiological responses and behavior of animals. Animals may also use appeasing pheromones to calm others down and reduce fighting behavior. An example of this in humans is that maternal breast odor is both attractive to infants and has positive emotional effects.
Vocal cues – Vocal communication can be used to indicate familiarity, emotions, and help with attachment formation. In marmosets, a species that use vocal communication, stress hormone levels decrease more when hearing a familiar voice compared to hearing an unfamiliar one.
Visual cues – In certain animals, visual cues may be enough to evoke the effects of social buffering. These effects were shown in sheep, where seeing pictures of other sheep's faces reduced behavioral and physiological stress responses. Zebrafish have been observed to communicate about danger with visual cues, leading to social buffering from conspecifics in response to the threat of predators.
References
Wikipedia Student Program
Social psychology
Psychology
Social networks
Interpersonal relationships | Social buffering | [
"Biology"
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"Behavior",
"Human behavior",
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75,126,181 | https://en.wikipedia.org/wiki/Nxtpaper | TCL NXTPAPER is a display technology developed by TCL Corporation that attempts to replicate the experience of reading on paper to improve eye comfort. TCL claims that the NXTPAPER technology reduces blue light emissions, which are often linked to digital eye strain and sleep disturbances. It also includes anti-glare properties, designed to make screen reading more akin to reading paper, further reducing strain on the eyes.
TCL has implemented NXTPAPER technology in various products, including tablets and smartphones. Devices featuring NXTPAPER displays include the TCL NXTPAPER 10s and TCL's 40 NXTPAPER series smartphones.
References
Chinese brands
Computer display standards
LCD brand names | Nxtpaper | [
"Technology"
] | 138 | [
"Mobile technology stubs"
] |
75,126,609 | https://en.wikipedia.org/wiki/Muironolide%20A | Muironolide A is a tetrachloro polyketide discovered in 200 that has two unusual structural details: a hexahydro-1H-isoindolone-triketide ring and a trichlorocarbinol ester. It is suspected that it is the product of a sponge–microorganism (cyanobacteria) association. It was isolated from the marine sponge Phorbas sp.
Biosynthesis and synthesis
Muironolide A possibly has its biosynthetic route coming from PKS 1 responsible for forming the lactonic ring, with an amino acid residue, which forms the isoindole ring present in the molecule and successive enzymatic transformations of reduction, oxidation, cyclication, denaturation and additions of halogens ( Chlorine - Cl) result in the final molecule.
There are proposals for synthetic routes that elucidate the synthesis process. In 2015, Xiao and collaborators carried out the synthesis and structural revision of muironolide A molecules.
Biological activities
Muironolide A has already been tested for antineoplastic activity in 56 different models using different cell lines and did not provide biological activity in any of them. Phorbas sp. also produces the macrolides phorboxazoles A and B and phorbaside A, which do have antifungal and cytostatic activity.
References
Polyketides
Cyclopropyl compounds
Lactones
Lactams
Trichloromethyl compounds
Heterocyclic compounds with 3 rings | Muironolide A | [
"Chemistry"
] | 319 | [
"Biomolecules by chemical classification",
"Natural products",
"Polyketides"
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75,126,778 | https://en.wikipedia.org/wiki/Shneider-Miles%20scattering | Shneider-Miles scattering (also referred to as collisional scattering or quasi-Rayleigh scattering) is the quasi-elastic scattering of electromagnetic radiation by charged particles in a small-scale medium with frequent particle collisions. Collisional scattering typically occurs in coherent microwave scattering of high neutral density, low ionization degree microplasmas such as atmospheric pressure laser-induced plasmas. Shneider-Miles scattering is characterized by a 90° phase shift between the incident and scattered waves and a scattering cross section proportional to the square of the incident driving frequency (). Scattered waves are emitted in a short dipole radiation pattern. The variable phase shift present in semi-collisional scattering regimes allows for determination of a plasma's collisional frequency through coherent microwave scattering.
History
Mikhail Shneider and Richard Miles first described the phenomenon mathematically in their 2005 work on microwave diagnostics of small plasma objects. The scattering regime was experimentally demonstrated and formally named by Adam R. Patel and Alexey Shashurin and has been applied in the coherent microwave scattering diagnosis of small laser-induced plasma objects.
Physical description
A plasma, consisting of neutral particles, ions, and unbound electrons, responds to the oscillating electric field of incident electromagnetic radiation primarily through the motion of electrons (ions and neutral particles can often be regarded as stationary due to their larger mass). If the frequency of the incident radiation is sufficiently low and the plasma frequency is sufficiently high (corresponding to the Rayleigh scattering regime), the electrons will travel until the plasma object becomes polarized, counteracting the incident electric field and preventing further movement until the incident field reverses direction. If the frequency of the incident radiation is sufficiently high and the plasma frequency is sufficiently low (corresponding to the Thomson scattering regime), electrons will only travel a short distance before the electric field reverses direction, making collisions with other particles unlikely during a given oscillation.
If the frequency on the incident radiation is intermediate and a high density of neutral particles and ions is present, electrons will travel far enough to collide many times with other particles but not far enough to significantly polarize the plasma object. This characterizes the collisional scattering regime. The linear oscillation of unbound electrons in a relatively-small space gives rise to a short-dipole radiation pattern.
This is analogous to a spring-mass-damper system, where the polarization of the plasma object creates the restoring force and the drag due to collisions with other particles creates the damping force. The phase shift of the scattered wave is 90º in the Shneider-Miles regime due to the drag force being dominant.
Note that, in this context, Rayleigh scattering is regarded as volumetric small particle scattering rather than an even broader short-dipole approximation of the radiation. Otherwise, Thomson scattering would fall under the banner of "Rayleigh". Mie scattering experiences a similar ambiguity.
Mathematical description
The scattering cross section of an object () is defined by the time-averaged power of the scattered wave () divided by the intensity of the incident wave (): .
Starting with the assumptions that a plasma object is small relative to the incident wavelength, thin relative to the skin depth, unmagnetized, and homogenous, the scattering cross-section of the plasma object can be determined by the following equation, where is the electron charge, is the electron mass, is the number of unbound electrons in the plasma object, is the geometrically-determined depolarization factor, is the incident wave circular frequency, is the plasma frequency, and is the effective momentum-transfer collisional frequency (not to be confused with collisional frequency).
(The above equation is derived from the Drude-Lorentz-Sommerfeld model. It neglects transient effects of electron motion and is only qualitatively applicable to Rayleigh scattering due to neglecting evanescence effects - strict consideration of boundary conditions is often required to capture the case of negative permittivity.). The total cross section can related to the cross section of an individual electron () according to the equation , since the electron motion will be in phase assuming that the plasma object is small relative to the incident wavelength.
The scattering regime is determined by the dominant term in the denominator. Collisional scattering refers to the assumption that , allowing the total scattering cross section to be expressed as:
The collisional scattering cross-section can also be expressed in terms of the Thomson scattering cross section (), which is independent of the plasma geometry and collisional frequency according to the following equation.
References
Spectroscopy | Shneider-Miles scattering | [
"Physics",
"Chemistry"
] | 929 | [
"Instrumental analysis",
"Molecular physics",
"Spectroscopy",
"Spectrum (physical sciences)"
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75,127,626 | https://en.wikipedia.org/wiki/Your%20Favourite%20London%20Sounds | Your Favourite London Sounds is an album compiled by English musician Peter Cusack and released in November 2001 by the London Musicians Collective (LMC). It collects 40 field recordings of sounds around the English city of London, most of which were recorded by Cusack. The project originated when the LMC hosted a temporary radio station for the 1998 Meltdown Festival, which Cusack used to ask festival goers and listeners what their favourite 'London sound' was. He received hundreds of responses, many of which were varied and often personal.
The sounds on the recording are highly diverse and vary between outdoor and indoor sounds, some of which are famous and some of which are more atypical. Several sounds are specific to London while others are broader. On release, the album received critical acclaim, including being named the week's best CD by The Guardian, and inspired radio and newspaper commentary. Cusack commented that it received more attention than his musical work. Ultimately, the London project was the first in Cusack's larger Favourite Sounds Project, which visited other cities across the world.
Background and recording
As part of John Peel's Meltdown Festival in June 1998, the London Musicians Collective (LMC) launched and ran a temporary radio station, Resonance 107.3 FM, over four weeks. It was the first ever London station dedicated to radio art, and later evolved into the artist-run Resonance FM. The LMC and particularly the member Peter Cusack, an improvisational musician, used Resonance 107.3 FM as an opportunity to undertake research, asking festival goers and listeners to send in or tell of their "favourite London sound". This formed the basis of a programme, London Soundscape. Cusack received hundreds of responses, and then travelled around London to capture all the relevant sounds himself, providing hours of raw material.
There was no overwhelming "favourite London sound" to emerge from the replies, with few people offering the same answer as anyone else. Many of the selections were surprisingly personal, and varied between outdoor and indoor sounds (such as post hitting a doormat). Cusack was surprised by how considered and largely serious the answers were, as well as how detailed and specific they could be. He found this "especially encouraging", saying: "It has been said in soundscape circles that because of ever increasing noise we are losing the ability to hear. I think this is nonsense. We may find it pretty difficult to talk or think about sound but we certainly hear it, including the details within all the noise." He expressed surprise at minor details that participants often included in their answers, ones which "may not be sonically apparent but which for them were important." He believed such sounds slowly gain personal significance to those who "travel the same route everyday". The sound of Big Ben was the most popular choice, while some surprising picks included arcade machines and traffic, but a large number of responses offered a collection of sounds rather than an individual one.
Realised in 2001, Your Favourite London Sounds is a CD based on responses from the questionnaire, featuring 40 examples of London sounds given as choices. Some of the recordings are the same as those which debuted on the 1998 radio station. Cusack compiled and edited the disc and recorded 35 of its tracks; the others were recorded by Matthias Krispert ("Brixton Station"), Tom Wallace ("Bus Pressure"), Bunny Schendler ("Euston Main Line Railway Station"), Clive Bell ("Tottenham Hotspurs Football Club, White Hart Lane") and Syngen Brown ("LRT Transformer, Putney").
Contents
According to The Los Angeles Times writer Jill Lawless, Your Favourite London Sounds is an aural collage of London's distinctive soundscape, one which "has inspired Londoners to close their eyes and listen to their city." Author David M. Frohlich writes the project demonstrates that the favourite sounds of London are "highly idiosyncratic, and just as likely to include man-made sounds as natural sounds", while Lawless said the release "confirms Londoners' intense and idiosyncratic relationship with the urban soundscape." The subjects are diverse, ranging from frying onions, "rain on skylight while lying in bed", "the call to prayer from an east London mosque", double-decker buses, coffee makers, a voicemail message, a bicycle crossing a canal towpath, a hissing bus door, a noisy street market, birds, traffic, taxis, trains, geese, wailing sirens, humming power plants, lapping rivers and "electronic bleeps at supermarket checkouts." Kenneth Goldsmith opines that the project provides "an odd way to think about a city", while according to John L. Walters, the release is "not that outlandish" as many of Cusack's prior albums, including Where Is the Green Parrot? (1999), similarly include lengthy field recordings.
Some sounds are specific to London, such as the London Underground sounds (such as the "mind the gap" announcement) and the bell on the 73 Bus. Cusack said many people "mentioned bus sounds – but not just any bus. It had to be the No. 73 bus, or the No. 12 bus. It was much more personal than I was expecting." He believed that different parts of the world sound very different to each other one part of the world, adding: "On the London Underground, the way the 'mind the gap' echoes down the tunnel comes to you in such a London way, you can't fail to know where you are when you hear it." As Goldsmith describes, some sounds captured in language-laden locations (such as coffee shops and markets) catch locals in conversation, bringing "a specific local flavour to the tracks", while other sounds are not often associated with cities, including rolling thunder and "the unaccompanied chirping of birds". Several sounds are presented with brief descriptions, which Goldsmith says gives them "more poetic weight".
Lawless says that in addition to "predictable natural sounds," such as a fountain, blackbirds, and rising and falling barges moored in the Thames, there are less predictable sounds and several "extremely delicate and specific" ones, such as bicycle wheels riding over "loose concrete slabs" on a specific towpath, while others are more generic, including turnstiles moving on entry to a football game. She also notes the inclusion of several endangered sounds, such as "the slamming of old-fashioned train doors, some of the few not yet replaced by mechanical sliding doors." According to David Toop, sounds vary from famous (Big Ben and "mind the gap"), social (a club queue and Dalston Market), highly personal (a phone message), "universally shared soundmarks" ("post through letterbox", "key in door") and unusual "ear-of-the-musician" answers. Toop also characterises some sounds as possessing "a distinct air of cinema futurism", citing the "disembodied announcements echoing in public space, polyglot languages overhead on the transport system, impersonal reminders of heightened security in the beleaguered city, ageing machinery grinding toward obsolesce, its tortured wails a taunting reminder of our financially draining dependence on clockwork history."
The disc opens with the sound of Big Ben, the most popular choice, which was captured at street level. Cusack's favourite sound is "a nightingale singing against the hum of an electricity substation", admiring the juxtaposition between "the birdsong and the crass, everyday urban hum." He also singled out the sounds of Brick Lane for clearly presenting the area's strong Bangladeshi community. Toop's own choices were the spatial sounds of distant emergency sirens at night and the high-pitched croaks of swifts, whose appearances throughout the year provoke "seasonal nostalgia". Drummer Charles Hayward's choice was "the Deptford Grid electricity sub-station at the edge of the Thames, a saturating drone washed by waves from the river." Hayward admired how people can walk through the overtones, and appreciates "the strange conjunction of that and the sounds of the river, and the sounds of people walking through the pebbles." The sound of an espresso machine was described by Walters as "a delicious, drawn-out sequence of clunks and drips, hissing and explosive boiling recorded in close-up, fetishistic detail"; it is introduced by its nominator as "not specifically a London sound". On the track "Deptford Market", Cusack is heard explaining to a woman that he is recording "all the clanging as you take all the stuff down."
Release and reception
Your Favourite London Sounds was released as a CD in November 2001 by the LMC's eponymous label. The booklet lists further responses which are not captured on the recording, including "a baby laughing on the Underground", "my boyfriend's orgasms and I love yous" and "none, I war earplugs." Despite the humdrum nature of its contents, the CD was critically praised by reviewers and inspired newspaper articles and radio discussions. Cusack commented that the release had received "far more interest than any of my musical work has ever had". He was pleased with the final recording, commenting: "It was obvious from the responses that people did listen in a lot of detail."
In his review for The Guardian, Walters called Your Favourite London Sounds a "strangely comforting" and "pleasingly mundane" disc with a concept that is theoretically endless. He noted that the LMC consider it to be an "audio postcard" and believed it would sell strongly in tourist shops across London, adding: "It's a Christmas present for homesick émigrés; a souvenir; a generous sample library; a versatile source of filler material for radio schedulers; an audio document of contemporary urban life. It will bring a smile of recognition to many harassed city-dwellers." He named it the newspaper's "CD of the week." In the New York Press, Goldsmith believed the group of sounds to be somewhat uninteresting, with subjective selections that suggest the participants were "not really thinking about how to define the ultimate sound of London." However, he added that as the sounds they choice were those they "encountered in their day-to-day routine", the resulting release is "a more realistic sonic picture of the city than you would get from a promotional or commercial project that tried to describe a city." He also credited the project with allowing him to notice more sounds in his native New York City. The Wire included the album in the "Outer Limits" section of their list of the best records of 2001.
Legacy
The London project was ultimately the beginning of what became Cusack's ongoing Favourite Sounds Project, which later explored diverse cities including Manchester, Birmingham, Southend-on-Sea, Prague, Berlin, Toronto and Beijing. As with the London instalment, all its successors focused on discovering what locals find positive about their cities and neighbourhoods and how they interact with them. In The Bloomsbury Handbook of the Anthropology of Sound (2021), Sam Auinger and Dietmar Offenhuber single out the London edition for reflecting "changes in the sensory qualities of the city as a result of the expansion of the Thames shore into a recreational area."
Frohlich, in his 2004 book Audiophotography: Bringing Photos to Life with Sounds, considers Your Favourite London Sounds to have been part of the emergence of sound-based artistic projects which explore the sentimental value of sound, projects which reveal "a rich set of meanings and preferences for particular kinds of sounds." Clive Bell of Variant magazine considers the recording of Deptford Creek to have been "particularly memorable" for bringing the power station hum with the sound of the Thames. Emily Nunn of The Chicago Tribune considers the London project to be the apogee of Cusack's field recording work, and notes Favourite Sounds of Beijing (2007) as a sequel. She believed such projects were "somewhat old-fashioned" by 2006 standards, but noted the London disc "sold well enough to pay for the project." Your Favourite London Sounds also inspired Jesse Seay's Your Favourite Chicago Sounds (2006), an online public archive of Chicago sounds that Cusack helped organise.
Track listing
"Big Ben" – 0:51
"London Bridge Station" – 2:07
"Brixton Station" – 1:49
"'Mind The Gap', Bank Underground Station" – 0:49
"The Bank of England, 1.00AM" – 1:36
"Blackbird Dawn Chorus, 4.00AM in May" – 2:05
"Brick Lane" – 1:51
"Bagel Shop, Brick Lane" – 1:22
"The Bell on the 73 Bus" – 0:25
"Bus Pressure" – 1:00
"Butlers Wharf: Thames Sounds" – 2:01
"Canal Towpath Stones" – 2:01
"Club Queue, Hoxton" – 1:47
"Coffee, Soho" – 1:39
"Dalston Market" – 1:29
"Deptford Market" – 2:09
"Deptford Grid Electricity Sub-Station"– 2:20
"Regent's Park to Oxford Circus" – 5:00
"Escalator, King's Cross Underground Station" – 0:40
"Euston Main Line Railway Station" – 1:21
"Slamming Doors, Victoria Station" – 1:36
"Evening Birds in Abney Park Cemetery, Early May" – 1:59
"Michelle's Phone Message" – 0:58
"Fountain in Victoria Park, 1.00AM" – 1:25
"The Great Court of the British Museum " – 2:09
"Helicopter/East London Mosque" – 5:51
"Key in Door" – 0:36
"Onions Frying in My Flat" – 1:10
"Post Through Letterbox" – 1:20
"Nightingale/Hum" – 0:56
"London Thunder" – 4:09
"Rain on Skylight While Lying in Bed" – 1:31
"Bleeps at the Supermarket Checkout" – 0:46
"Tottenham Hotspurs Football Club, White Hart Lane" – 2:55
"St James's Park: Two Species of Baby" – 0:59
"Under the Flyover, Hackney Wick" – 1:06
"Taxis Waiting at Euston Station" – 0:59
"LRT Transformer, Putney" – 1:40
"Swifts Over Stoke Newington" – 0:54
"16th Floor Up" – 2:35
Personnel
Adapted from the liner notes of Your Favourite London Sounds.
Peter Cusack – compiling, editing, recording (all tracks except 3, 10, 20, 34 and 38)
Matthias Kispert – recording ("Brixton Station")
Tom Wallace – recording ("Bus Pressure")
Bunny Schendler recording ("Euston Main Lin Railway Station")
Clive Bell – recording ("Tottenham Hotspurs Football Club, White Hart Lane")
Syngen Brown – recording ("LRT Transformer, Putney")
Tom Brake – voice ("Coffee, Soho")
Evrah – idea ("LRT Transformer, Putney")
Dave Mandl – photography
Ed Baxter – booklet design
References
2001 albums
Field recording
Sound collage albums
Sound effects albums
Culture in London
Arts in London
Works about London
London in popular culture | Your Favourite London Sounds | [
"Engineering"
] | 3,197 | [
"Audio engineering",
"Field recording"
] |
75,128,351 | https://en.wikipedia.org/wiki/EEVE | EEVE is a Belgian company that develops and produces personal robots.
Since its foundation in 2017, EEVE has used two alternative names: AIRobots (2017) and The Toadi Order (2018–2020).
EEVE's flagship product, the perimeter-free lawn robot Willow, is a robot capable of mowing lawns and conducting surveillance, with the ability to equip additional tools and operate solely on computer vision and artificial intelligence. Willow was introduced in the United States via a Kickstarter campaign in 2020 with object recognition and security features. The first test robot deliveries in the US occurred in 2023.
See also
Robotic lawn mower
References
External links
Domestic robots
Lawn mower manufacturers | EEVE | [
"Technology"
] | 143 | [
"Home automation",
"Domestic robots"
] |
63,622,786 | https://en.wikipedia.org/wiki/DUT-5 | DUT-5 (DUT ⇒ Dresden University of Technology) is a material in the class of metal-organic frameworks (MOFs). Metal-organic frameworks are crystalline materials, in which metals are linked by ligands (linker molecules) to form repeating three-dimensional structures known as coordination entities. The DUT-5 framework is an expanded version of the MIL-53 structure and consists of Al3+ metal centers and biphenyl-4,4'-dicarboxylate (BPDC) linker molecules. It consists of inorganic [M-OH] chains, which are connected by the biphenyl-4,4'-dicarboxylate linkers to four neighboring inorganic chains. The resulting structure contains diamond-shaped micropores extending in one dimension.
Structural analogs
The DUT-5 structure was initially synthesized with Al3+ as metal center, but other isostructural materials, whose structures are comparable to DUT-5, have also been prepared with metals having oxidation states of +II or +IV .
Due to the tool-box like design of metal-organic framework materials, other organic molecules, which are structurally similar to biphenyl-4,4'-dicarboxylate, have also been used as linker molecules for the synthesis of functionalized DUT-5 materials, which contain uncoordinated functional groups in their framework structure. For the functionalized DUT-5 materials, the additional functional groups at the functional biphenyl-4,4'dicarboxylate linkers in the DUT-5 framework have been used for post-synthetic modification reactions to further modify the framework structure after the initial synthesis or to alter the adsorption properties.
References
Metal-organic frameworks | DUT-5 | [
"Chemistry",
"Materials_science"
] | 370 | [
"Porous polymers",
"Metal-organic frameworks"
] |
63,622,817 | https://en.wikipedia.org/wiki/S.%20Patricia%20Becerra | Sofia Patricia Becerra is a biochemist specializing in the retina. She researches protein structure and function in relation to drug development for combating blindness. Becerra is a senior investigator at the National Eye Institute.
Early life and education
Becerra was born in Lima. She attended Pontifical Catholic University of Peru before completing a bachelor of science at Cayetano Heredia University. Becerra received her Ph.D. in biochemistry from the University of Navarra in 1979 studying lipid-protein interactions of liver mitochondria enzymes. She received postdoctoral research training with at the National Cancer Institute studying enzymology of DNA polymerases and exonucleases, followed by training at the National Institute of Allergy and Infectious Diseases (NIAID) in molecular virology of adeno-associated virus. She returned to Wilson's lab as an expert to study structure-function relationships of HIV reverse transcriptase.
Career
Becerra joined the National Eye Institute (NEI) as a visiting scientist in 1991, became an investigator in 1994, and was promoted to principal investigator in 2001 to study the biochemistry of PEDF. The interests of her section are in protein structure as it relates to function, with a focus on the interactions of components involved in cell differentiation, survival, and maintenance. Her research at NEI has applied these interests to systems in the retina. Becerra also investigates protein structure and function in relation to drug development for combating blindness.
Selected works
References
Living people
Year of birth missing (living people)
National Institutes of Health people
20th-century women scientists
21st-century women scientists
Women medical researchers
Expatriate academics in the United States
20th-century Peruvian scientists
21st-century Peruvian scientists
Peruvian women scientists
Peruvian medical researchers
Peruvian chemists
Women biochemists
Peruvian biologists
20th-century biochemists
21st-century biochemists
Peruvian emigrants to the United States
Scientists from Lima
University of Navarra alumni | S. Patricia Becerra | [
"Chemistry"
] | 396 | [
"Biochemists",
"Women biochemists"
] |
63,622,954 | https://en.wikipedia.org/wiki/Auxiliary%20normed%20space | In functional analysis, a branch of mathematics, two methods of constructing normed spaces from disks were systematically employed by Alexander Grothendieck to define nuclear operators and nuclear spaces.
One method is used if the disk is bounded: in this case, the auxiliary normed space is with norm
The other method is used if the disk is absorbing: in this case, the auxiliary normed space is the quotient space
If the disk is both bounded and absorbing then the two auxiliary normed spaces are canonically isomorphic (as topological vector spaces and as normed spaces).
Induced by a bounded disk – Banach disks
Throughout this article, will be a real or complex vector space (not necessarily a TVS, yet) and will be a disk in
Seminormed space induced by a disk
Let will be a real or complex vector space. For any subset of the Minkowski functional of defined by:
If then define to be the trivial map and it will be assumed that
If and if is absorbing in then denote the Minkowski functional of in by where for all this is defined by
Let will be a real or complex vector space. For any subset of such that the Minkowski functional is a seminorm on let denote
which is called the seminormed space induced by where if is a norm then it is called the normed space induced by
Assumption (Topology): is endowed with the seminorm topology induced by which will be denoted by or
Importantly, this topology stems entirely from the set the algebraic structure of and the usual topology on (since is defined using the set and scalar multiplication). This justifies the study of Banach disks and is part of the reason why they play an important role in the theory of nuclear operators and nuclear spaces.
The inclusion map is called the canonical map.
Suppose that is a disk.
Then so that is absorbing in the linear span of
The set of all positive scalar multiples of forms a basis of neighborhoods at the origin for a locally convex topological vector space topology on
The Minkowski functional of the disk in guarantees that is well-defined and forms a seminorm on
The locally convex topology induced by this seminorm is the topology that was defined before.
Banach disk definition
A bounded disk in a topological vector space such that is a Banach space is called a Banach disk, infracomplete, or a bounded completant in
If its shown that is a Banach space then will be a Banach disk in TVS that contains as a bounded subset.
This is because the Minkowski functional is defined in purely algebraic terms.
Consequently, the question of whether or not forms a Banach space is dependent only on the disk and the Minkowski functional and not on any particular TVS topology that may carry.
Thus the requirement that a Banach disk in a TVS be a bounded subset of is the only property that ties a Banach disk's topology to the topology of its containing TVS
Properties of disk induced seminormed spaces
Bounded disks
The following result explains why Banach disks are required to be bounded.
Hausdorffness
The space is Hausdorff if and only if is a norm, which happens if and only if does not contain any non-trivial vector subspace.
In particular, if there exists a Hausdorff TVS topology on such that is bounded in then is a norm.
An example where is not Hausdorff is obtained by letting and letting be the -axis.
Convergence of nets
Suppose that is a disk in such that is Hausdorff and let be a net in
Then in if and only if there exists a net of real numbers such that and for all ;
moreover, in this case it will be assumed without loss of generality that for all
Relationship between disk-induced spaces
If then and on so define the following continuous linear map:
If and are disks in with then call the inclusion map the canonical inclusion of into
In particular, the subspace topology that inherits from is weaker than 's seminorm topology.
The disk as the closed unit ball
The disk is a closed subset of if and only if is the closed unit ball of the seminorm ; that is,
If is a disk in a vector space and if there exists a TVS topology on such that is a closed and bounded subset of then is the closed unit ball of (that is, ) (see footnote for proof).
Sufficient conditions for a Banach disk
The following theorem may be used to establish that is a Banach space.
Once this is established, will be a Banach disk in any TVS in which is bounded.
Note that even if is not a bounded and sequentially complete subset of any Hausdorff TVS, one might still be able to conclude that is a Banach space by applying this theorem to some disk satisfying
because
The following are consequences of the above theorem:
A sequentially complete bounded disk in a Hausdorff TVS is a Banach disk.
Any disk in a Hausdorff TVS that is complete and bounded (e.g. compact) is a Banach disk.
The closed unit ball in a Fréchet space is sequentially complete and thus a Banach disk.
Suppose that is a bounded disk in a TVS
If is a continuous linear map and is a Banach disk, then is a Banach disk and induces an isometric TVS-isomorphism
Properties of Banach disks
Let be a TVS and let be a bounded disk in
If is a bounded Banach disk in a Hausdorff locally convex space and if is a barrel in then absorbs (that is, there is a number such that
If is a convex balanced closed neighborhood of the origin in then the collection of all neighborhoods where ranges over the positive real numbers, induces a topological vector space topology on When has this topology, it is denoted by Since this topology is not necessarily Hausdorff nor complete, the completion of the Hausdorff space is denoted by so that is a complete Hausdorff space and is a norm on this space making into a Banach space. The polar of is a weakly compact bounded equicontinuous disk in and so is infracomplete.
If is a metrizable locally convex TVS then for every bounded subset of there exists a bounded disk in such that and both and induce the same subspace topology on
Induced by a radial disk – quotient
Suppose that is a topological vector space and is a convex balanced and radial set.
Then is a neighborhood basis at the origin for some locally convex topology on
This TVS topology is given by the Minkowski functional formed by which is a seminorm on defined by
The topology is Hausdorff if and only if is a norm, or equivalently, if and only if or equivalently, for which it suffices that be bounded in
The topology need not be Hausdorff but is Hausdorff.
A norm on is given by where this value is in fact independent of the representative of the equivalence class chosen.
The normed space is denoted by and its completion is denoted by
If in addition is bounded in then the seminorm is a norm so in particular,
In this case, we take to be the vector space instead of so that the notation is unambiguous (whether denotes the space induced by a radial disk or the space induced by a bounded disk).
The quotient topology on (inherited from 's original topology) is finer (in general, strictly finer) than the norm topology.
Canonical maps
The canonical map is the quotient map which is continuous when has either the norm topology or the quotient topology.
If and are radial disks such that then so there is a continuous linear surjective canonical map defined by sending
to the equivalence class where one may verify that the definition does not depend on the representative of the equivalence class that is chosen.
This canonical map has norm and it has a unique continuous linear canonical extension to that is denoted by
Suppose that in addition and are bounded disks in with so that and the inclusion is a continuous linear map.
Let and be the canonical maps.
Then and
Induced by a bounded radial disk
Suppose that is a bounded radial disk.
Since is a bounded disk, if then we may create the auxiliary normed space with norm ; since is radial,
Since is a radial disk, if then we may create the auxiliary seminormed space with the seminorm ; because is bounded, this seminorm is a norm and so
Thus, in this case the two auxiliary normed spaces produced by these two different methods result in the same normed space.
Duality
Suppose that is a weakly closed equicontinuous disk in (this implies that is weakly compact) and let
be the polar of
Because by the bipolar theorem, it follows that a continuous linear functional belongs to if and only if belongs to the continuous dual space of where is the Minkowski functional of defined by
Related concepts
A disk in a TVS is called infrabornivorous if it absorbs all Banach disks.
A linear map between two TVSs is called infrabounded if it maps Banach disks to bounded disks.
Fast convergence
A sequence in a TVS is said to be fast convergent to a point if there exists a Banach disk such that both and the sequence is (eventually) contained in and in
Every fast convergent sequence is Mackey convergent.
See also
Notes
References
Bibliography
External links
Nuclear space at ncatlab
Functional analysis | Auxiliary normed space | [
"Mathematics"
] | 1,922 | [
"Functional analysis",
"Mathematical objects",
"Functions and mappings",
"Mathematical relations"
] |
63,623,321 | https://en.wikipedia.org/wiki/Unit%20%28Norway%29 | Unit, which labels itself as the Norwegian "directorate for ICT and joint services in higher education and research", is the within the Ministry of Education and Research which provides governance of and access to shared information and communications technology (ICT) services. Unit was created on January 1, 2018, following a merger of BIBSYS, and parts of Uninett.
See also
National Library of Norway
Open access in Norway
Project DEAL
References
Further reading
External links
2018 establishments in Norway
Government agencies established in 2018
Organisations based in Trondheim
Government agencies of Norway
Information and communications technology | Unit (Norway) | [
"Technology"
] | 112 | [
"Information and communications technology"
] |
63,623,716 | https://en.wikipedia.org/wiki/NAD%2B%20Five-prime%20cap | In molecular biology, the NAD+ five-prime cap (NAD+ 5' cap) refers to a molecule of nicotinamide adenine dinucleotide (NAD+), a nucleoside-containing metabolite, covalently bonded the 5' end of cellular mRNA. While the more common methylated guanosine (m7G) cap is added to RNA by a capping complex that associates with RNA polymerase II (RNAP II), the NAD cap is added during transcriptional initiation by the RNA polymerase itself, acting as a non-canonical initiating nucleotide (NCIN). As such, while m7G capping can only occur in organisms possessing specialized capping complexes, because NAD capping is performed by RNAP itself, it is hypothesized to occur in most, if not all, organisms.
The NAD+ 5' cap has been observed in bacteria, contrary to the long-held belief that prokaryotes lacked 5'-capped RNA, as well as on the 5' cap of eukaryotic mRNA, in place of the m7G cap. This modification also potentially allows for selective degradation of RNA]within prokaryotes as different pathways are involved in the degradation of NAD+-capped and uncapped 5′-triphosphate-RNAs.
In eukaryotic cells, while the more commonly observed m7G cap promotes the stability of the mRNA and supports translation, the NAD+ cap targets the RNA transcript for decay, facilitated by the non-canonical decapping enzyme, DXO. Considering the centrality of NAD in redox chemistry and post-translational protein modification, its attachment to RNA represents potentially undiscovered pathways in RNA metabolism and regulation.
Function in prokaryotes
In prokaryotes, the 5' NAD+ modification is established by bacterial RNAP during transcription initiation and has been shown to display functions analogous to those of the eukaryotic 5' cap. In-vitro transcribed NAD-modified RNA was shown to be more resistant to RNase E, the main enzyme in the decay pathway of E. coli. NAD-modification further was shown to decelerate RNA processing by RNA pyrophosphohydrolase (RppH), which is known to trigger RNase-E-mediated decay through the conversion of 5′-triphosphate-RNA to 5′-monophosphate-RNA. Nudc, a nudix phosphohydrolase, can decap NAD-RNA through hydrolyzing NAD(H) into NMN(H) and AMP, causing RNase-E-mediated decay, but is inactive against 5′-triphosphate-RNA. This 5' modification allows for the selective initiation of degradation for a subset of RNAs as the NAD-capped RNAs are stabilized in the presence of RppH, but are decapped by Nudc, while the 5′-triphosphate-RNAs are susceptible to RppH but not Nudc.
Next generation sequencing (NGS) of the NAD-RNA conjugates in E. coli revealed an abundance of a specific group of small regulatory RNAs (sRNAs) which are known to be involved in stress response systems, as well as enzymes involved in cellular metabolism. The small number of RNA transcripts with a NAD cap might allow the cell to selectively degrade these RNAs separate from other pathways. Considering that the stress responses are known to affect NAD+ concentration, this finding further supports the possibility of undiscovered pathways linking the energetic state of a cell to mRNA turnover.
NAD capping has also been suggested to recruit specific proteins to the 5' end of the RNA as NAD is one of the most common protein ligands. NAD-binding pockets are well characterized in many proteins and could help the localization of the RNA to an enzyme or receptor. Many NAD-utilizing metabolic enzymes can also bind to RNA, presenting the possibility of unknown ribonucleoprotein complexes.
Function in eukaryotes
NAD+ 5' capped RNA have been found in yeast, humans, and Arabidopsis thaliana. In eukaryotes, the NAD+ cap is removed by non-canonical decapping enzymes from the DXO family. DeNADing by DXO results in a 5' end monophosphate RNA distinct from NudC which results in NMN plus 5′ monophosphate RNA. Importantly, DXO is ~6 fold more efficient at decapping NAD+ compared to m7G, suggesting that it selectively degrades NAD-capped RNA rather than the more common m7G cap, similar to NudC.
The m7G cap has been shown to promote translation through recruitment of the initiation complex onto the mRNA. However, the NAD+-cap does not provide a similar function as NAD+-capped and polyadenylated mRNA displayed similar levels of translation in vitro to uncapped mRNA. Additionally, the 5' NAD+ cap further promotes decay of the RNA it is attached to, NAD+-capped and polyadenylated mRNA were demonstrated in vitro to be less stable than mRNAs lacking a 5' cap, suggesting that the NAD+ modification is actively facilitating DXO-mediated RNA decay.
While the relationship between RNA-binding proteins, such as glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and NAD+ concentration is established, the NAD+ cap has been hypothesized to represent a direct link between RNA expression levels and cellular metabolism. It is known that energy stresses such as glucose deprivation and caloric restriction influence NAD+ concentrations and can possibly impact NAD+ capping. Additionally, as low-nutrient conditions can affect mRNA stability, and seeing as NAD+ caps promote mRNA decay, it is possible that the energetic state of a cell could affect NAD+-capping and thus mRNA turnover. Certain findings, such as the higher abundance of NAD+-capped transcripts in stationary-phase bacteria as well as yeast grown on synthetic media, point toward this possibility.
References
Coenzymes
Nucleotides
Cellular respiration
Anti-aging substances | NAD+ Five-prime cap | [
"Chemistry",
"Biology"
] | 1,277 | [
"Cellular respiration",
"Anti-aging substances",
"Coenzymes",
"Organic compounds",
"Senescence",
"Biochemistry",
"Metabolism"
] |
63,623,830 | https://en.wikipedia.org/wiki/TMC-310911 | TMC-310911 (also known as ASC-09) is an antiviral drug which was originally researched as a treatment for HIV/AIDS. It is a protease inhibitor related to darunavir. While TMC-310911 was not ultimately developed as a medication for the treatment of AIDS, research has continued into potential applications in the treatment of other viral diseases, and in March 2020 it was entered into clinical trials for the treatment of COVID-19.
See also
Brecanavir
TMC-647055
References
Antiviral drugs
Isobutyl compounds | TMC-310911 | [
"Biology"
] | 123 | [
"Antiviral drugs",
"Biocides"
] |
63,626,564 | https://en.wikipedia.org/wiki/The%20Stonemason%20%28book%29 | The Stonemason: A History of Building Britain is a book written by Andrew Ziminski, published by John Murray in 2020. The book is divided into four parts, combining a chronological and geological approach, with each part concentrating on a single type of stone and how it is used in a particular architectural style and period. Partly an autobiography, the book features examples that are principally drawn from the author's own work in an area broadly corresponding to Wessex, and chapters are arranged to reflect the passage of a single year, beginning and ending at Samhain. Each chapter is preceded by a linocut print produced by Clare Venables.
The first part, "Sarsen", describes the neolithic structures around Avebury and Stonehenge, beginning at West Kennet Long Barrow. This is followed by "Limestone", which describes the Roman baths of Aquae Sulis and some surviving Anglo-Saxon churches, such as St Laurence's Church, Bradford-on-Avon. "Marble" considers the rise of Gothic architecture, and the influence of Purbeck Marble, which like other types of Purbeck stone is in fact a type of limestone. Finally "Concrete" discusses the influence of the Industrial Revolution on architecture around Bath, Somerset, and particularly the role played by the Kennet and Avon Canal and the Great Western Railway.
As well as being a working stonemason, Ziminski is a William Morris Craft Fellow at the Society for the Protection of Ancient Buildings, and a Fellow of the Society of Antiquaries of London.
Ziminski's second book, Church Going, his guide to the history and architecture of churches in Britain, was announced in March 2023 and published in October 2024.
Reviews
The book has received many positive reviews. In The Daily Telegraph Christopher Howse writes that "The mark of Ziminski's approach is that he knows what he is doing" and that "Ziminski is no mere recorder of impressions. He brings plenty of helpful information from history, geology and architecture." In The Sunday Telegraph Robert Leigh-Pemberton compares Ziminski to William Morris, concluding that "Ziminski is undertaking something more profound than the charm of this delightful book first suggests."
In The Spectator Harry Mount notes his "unparalleled understanding of this country's stones", while in Literary Review Will Wiles emphasises "the remarkable way that Ziminski weaves together architecture, craft, landscape, archaeology and natural history". In History Today Gillian Darley describes Ziminski as "thoughtful, observant and well-informed", while in The Times Literary Supplement Emma Wells writes that "Absorbing and engaging, The Stonemason perfectly captures the genius loci of the British landscape and its ancient buildings."
In The Times Jonathan Morrison praises the book as "uncompromisingly learned" and containing "moments of great lyricism", but notes that "the greatest regret is that you do not emerge feeling that you understand the stonemason's craft that much better". However, he concludes that "Ziminski fills you afresh with a longing to visit one of the most extraordinary regions in the world". Writing in the Evening Standard, Julian Glover describes the book as "compelling", "rooted in the making of England", and "a magical read".
References
External links
Book page at John Murray Press
HistoryExtra interview with Andrew Ziminski
Authors Website
2020 non-fiction books
John Murray (publishing house) books
Stonemasonry
British architectural history | The Stonemason (book) | [
"Engineering"
] | 732 | [
"Construction",
"Stonemasonry"
] |
63,626,991 | https://en.wikipedia.org/wiki/NGC%201325 | NGC 1325 is a flocculent spiral galaxy situated in the constellation of Eridanus. Located about 75 million light years away, it is a member of the Eridanus cluster of galaxies, a cluster of about 200 galaxies. It was discovered by William Herschel on 19 December 1799.
NGC 1325 has a Hubble classification of SBbc, which indicates it is a barred spiral galaxy with moderately wound arms. Its angular size on the night sky is 4.5' x 1.7'. The disk of the galaxy is inclined at an angle of 71° with the main axis aligned along a position angle of 232°. The rotation curve for the galaxy is flat across much of the radius from the core. The galaxy is moving away from the Milky Way with a heliocentric radial velocity of 1,588 km/s.
Supernovae
Two supernovae have been observed in NGC 1325:
SN 1975S was discovered by Justus Dunlap and Yvonne Dunlap at Corralitos Observatory on 30 December 1975 . Designated with a magnitude of 14.6, it was positioned east and north of the galactic nucleus. The color of this supernova and the rapid decline of the lightcurve suggest it was a type II supernova.
SN 2021yja (type II-P or typeIc, mag. 15.334) was discovered by ATLAS on September 8, 2021. A core-collapse supernova, it was initially categorized as a type II, but may instead be a type Ic.
References
External links
Eridanus (constellation)
Barred spiral galaxies
1325
012737
Eridanus Group | NGC 1325 | [
"Astronomy"
] | 336 | [
"Eridanus (constellation)",
"Constellations"
] |
63,626,999 | https://en.wikipedia.org/wiki/C/2019%20U6%20%28Lemmon%29 | C/2019 U6 (Lemmon), or Comet Lemmon is a long period comet with a near-parabolic orbit discovered by the Mount Lemmon Survey on October 31, 2019. It made its closest approach to the Sun on June 18, 2020. In June 2020 it was visible near the naked eye limit at an apparent magnitude of 6.0. It is the 3rd brightest naked eye comet of 2020 after C/2020 F3 (NEOWISE) and C/2020 F8 (SWAN). It remained visible near the naked eye limit in June.
This perihelion passage will decrease the comet's orbital period from about 10500 years to about 5200 years.
Even though C/2019 U6 has an Earth-MOID of , the closest approach to Earth was on June 29, 2020 at a distance of .
References
External links
Non-periodic comets
Near-Earth comets
Astronomical objects discovered in 2019
Comets in 2019
Comets in 2020 | C/2019 U6 (Lemmon) | [
"Astronomy"
] | 194 | [
"Astronomy stubs",
"Comet stubs"
] |
63,627,025 | https://en.wikipedia.org/wiki/NGC%201353 | NGC 1353 is a flocculent spiral galaxy situated in the constellation of Eridanus. Located about 70 million light years away, it is a member of the Eridanus cluster of galaxies, a cluster of about 200 galaxies. It was discovered by William Herschel on 9 December 1784.
NGC 1353 has a Hubble classification of SBb, which indicates it is a barred spiral galaxy. It is moving away from the Milky Way at 1547 km/s. Its size on the night sky is 3.4 by 1.4 arcminutes, which corresponds to a real size of 69,000 ly.
See also
NGC 2841, a famous flocculent spiral galaxy
References
External links
Eridanus (constellation)
Barred spiral galaxies
1353
013108
Eridanus Group | NGC 1353 | [
"Astronomy"
] | 166 | [
"Eridanus (constellation)",
"Constellations"
] |
63,627,199 | https://en.wikipedia.org/wiki/NGC%201439 | NGC 1439 is an elliptical galaxy located in constellation of Eridanus. Situated about 77 million light years away, it is a member of the Eridanus cluster of galaxies, a cluster of about 200 galaxies. It was discovered by William Herschel on 9 December 1784.
NGC 1439 has a Hubble classification of E1, which indicates it is an elliptical galaxy with no extensions. It is moving away from the Milky Way at a rate of 1,668 km/s. Its size on the night sky is 2.4' x 2.2' which is proportional to its real size of 54 000 ly.
NGC 1439 is an early-type galaxy. Despite their name, early-type galaxies are much older than spiral galaxies, and mostly comprise old, red-colored stars. Very little star formation occurs in these galaxies; the lack of star formation in elliptical galaxies appears to start at the center and then slowly propagates outward.
Most of the galaxies like NGC 1439 are dust poor. However, NGC 1439 contains more dust than usual.
Gallery
References
External links
Eridanus (constellation)
Elliptical galaxies
1439
013738
Eridanus Group | NGC 1439 | [
"Astronomy"
] | 239 | [
"Eridanus (constellation)",
"Constellations"
] |
63,627,281 | https://en.wikipedia.org/wiki/NGC%201332 | NGC 1332 is an almost edge-on elliptical galaxy located in constellation of Eridanus. Situated about 70 million light years away, it is a member of the Eridanus cluster of galaxies, a cluster of about 200 galaxies. It is also the brightest member of the NGC 1332 Group. It was discovered by William Herschel on 9 December 1784.
NGC 1332 has a Hubble classification of E, which indicates it is an elliptical galaxy. It is moving away from the Milky Way at a rate of 1,553 km/s. Its size on the night sky is 4.5' x 1.4' which is proportional to its real size of 92 000 ly.
NGC 1332 is an early-type galaxy. Despite their name, early-type galaxies are much older than spiral galaxies, and mostly comprise old, red-colored stars. Very little star formation occurs in these galaxies; the lack of star formation in elliptical galaxies appears to start at the center and then slowly propagates outward.
One supernova has been observed in NGC 1332: SN 1982E (type unknown, mag. 14) was discovered by Marina Wischnjewsky on 29 March 1982.
Black hole
NGC 1332 is known by its possessing a supermassive black hole at the center. In 2016, a team from United States and China used the Atacama Large Millimeter/submillimeter Array (ALMA) to collect high resolution data. They were able to measure the mass of the black hole. They determined the mass of about 660 million solar-masses with an uncertainty of just 10%. NGC 1332's black hole is the most massive black hole in the Eridanus Cluster, and it is even more massive than NGC 1399's black hole (NGC 1399 is the Fornax cluster's central galaxy).
Gallery
See also
List of NGC objects (1001–2000)
References
External links
Eridanus (constellation)
Elliptical galaxies
1332
012838
Eridanus Group
-04-09-011
[[Category:ESO objects|548- G 018]
UGCA objects
[[Category:IRAS catalogue objects|03240-2130]
17841209
Discoveries by William Herschel | NGC 1332 | [
"Astronomy"
] | 463 | [
"Eridanus (constellation)",
"Constellations"
] |
63,627,383 | https://en.wikipedia.org/wiki/NGC%201347 | NGC 1347 is a barred spiral galaxy situated in the constellation of Eridanus. It is at a distance of 81 million light years and is a member of the Eridanus cluster, a cluster of about 200 galaxies.
NGC 1347 has a Hubble classification of SBc, which indicates it is a barred spiral galaxy. It is moving away from the Milky Way at a rate of 1,760 km/s. Its size on the night sky is 1.5' x 1.3' which is proportional to its real size of 35 000 ly.
NGC 1347 forms a pair, named Arp 39, with the galaxy PGC 816443.
References
Eridanus (constellation)
Barred spiral galaxies
1347
039
012989
Eridanus Group | NGC 1347 | [
"Astronomy"
] | 159 | [
"Eridanus (constellation)",
"Constellations"
] |
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