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59,957,256 | https://en.wikipedia.org/wiki/Dibutylchloromethyltin%20chloride | Dibutylchloromethyltin chloride (DBCT) is a toxic organotin compound. It is a potent and irreversible ATP synthase inhibitor. DBCT is a volatile liquid with powerful vesicant effects.
See also
Tributyltin chloride
Oligomycin
References
ATP synthase inhibitors
Organotin compounds
Organochlorides
Blister agents
Tin(IV) compounds | Dibutylchloromethyltin chloride | [
"Chemistry"
] | 85 | [
"Blister agents",
"Chemical weapons",
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
59,957,477 | https://en.wikipedia.org/wiki/Urogenital%20hiatus | The urogenital hiatus is a large midline opening in the anteromedial part of the pelvic floor (more precisely, the pubococcygeal muscle), extending between the pubis (anteriorly), and rectum (posteriorly). Each levator ani muscle forms either lateral border of the hiatus.
The hiatus acccomodates the apex of the prostate in males, and gives passage to the urethra in both sexes, the vagina in females, the deep dorsal vein of clitoris (females) or penis (males), and nerves of the penis in males.
Clinical significance
The urogenital hiatus has been linked to urinary stress incontinence.
See also
Coccyx (tailbone)
Pubococcygeus muscle
Pelvic floor dysfunction
Perineology
Perineal hernia
Female genital prolapse
References
Sexual anatomy
Muscles of the torso
Women's health | Urogenital hiatus | [
"Biology"
] | 194 | [
"Sexual anatomy",
"Sex"
] |
59,958,774 | https://en.wikipedia.org/wiki/NGC%204095 | NGC 4095 is an elliptical galaxy located 330 million light-years away in the constellation Coma Berenices. The galaxy was discovered by astronomer William Herschel on April 26, 1785. NGC 4095 is a member of the NGC 4065 Group and is a LINER.
See also
List of NGC objects (4001–5000)
References
External links
4095
038324
Coma Berenices
Astronomical objects discovered in 1785
Elliptical galaxies
NGC 4065 Group
LINER galaxies | NGC 4095 | [
"Astronomy"
] | 97 | [
"Coma Berenices",
"Constellations"
] |
59,959,559 | https://en.wikipedia.org/wiki/Technology-critical%20element | A technology-critical element (TCE) is a chemical element that is a critical raw material for modern and emerging technologies, resulting in a striking increase in their usage. Similar terms include critical elements, critical materials, energy-critical elements and elements of security.
Many advanced engineering applications, such as clean-energy production, communications and computing, use emergent technologies that utilize numerous chemical elements.
In 2013, the U.S. Department of Energy (DOE) created the Critical Materials Institute to address the issue. In 2015, the European COST Action TD1407 created a network of scientists working and interested on TCEs, from an environmental perspective to potential human health threats.
A study estimated losses of 61 metals to help the development of circular economy strategies, showing that usespans of, often scarce, tech-critical metals are short.
List of technology-critical elements
The set of elements usually considered as TCEs vary depending on the source, but they usually include:
Seventeen rare-earth elements
The six platinum-group elements
Twelve assorted elements
Elements such as oxygen, silicon, and aluminum (among others) are also vital for electronics, but are not included in these lists due to their widespread abundance.
Applications of technology-critical elements
TCEs have a variety of engineering applications in fields such as energy storage, electronics, telecommunication, and transportation. These elements are utilized in cellular phones, batteries, solar panel(s), electric motor(s), and fiber-optic cables. Emerging technologies also incorporate TCEs. Most notably, TCEs are used in the data networking of smart devices tied to the Internet of Things (IoT) and automation.
Environmental considerations
The extraction and processing of TCEs may cause adverse environmental impacts. The reliance on TCEs and critical metals like cobalt can run the risk of the “green curse,” or using certain metals in green technologies whose mining may be damaging to the environment.
The clearing of soil and deforestation that is involved with mining can impact the surrounding biodiversity through land degradation and habitat loss. Acid mine drainage can kill surrounding aquatic life and harm ecosystems. Mining activities and leaching of TCEs can pose significant hazards to human health. Wastewater produced by the processing of TCEs can contaminate groundwater and streams. Toxic dust containing concentrations of metals and other chemicals can be released into the air and surrounding bodies of water.
Deforestation caused by mining results in the release of stored carbon from the ground to the atmosphere in the form of carbon dioxide (CO2).
See also
Conflict resource
List of elements facing shortage
Rare-earth element
Strategic material
Renewable energy#Conservation areas, recycling and rare-earth elements
References
Sets of chemical elements
Scarcity
History of technology
Natural materials
Minerals | Technology-critical element | [
"Physics",
"Technology"
] | 543 | [
"Natural materials",
"Science and technology studies",
"Materials",
"History of technology",
"History of science and technology",
"Matter"
] |
59,960,516 | https://en.wikipedia.org/wiki/NGC%204098 | NGC 4098 is an interacting pair of spiral galaxies located 330 million light-years away in the constellation Coma Berenices. NGC 4098 was discovered by astronomer William Herschel on April 26, 1785. It was then rediscovered by Hershel on December 27, 1786 was listed as NGC 4099. NGC 4098 is a member of the NGC 4065 Group.
NGC 4098 is interacting with the galaxy pair VV 62.
A candidate supernova of an unknown type, which was designated as SNhunt287 (PSN J12060084+2036183), was discovered in NGC 4098 on April 25, 2015.
References
External links
4098
038365
Coma Berenices
Astronomical objects discovered in 1785
Spiral galaxies
NGC 4065 Group
Interacting galaxies
07091 | NGC 4098 | [
"Astronomy"
] | 172 | [
"Coma Berenices",
"Constellations"
] |
59,961,754 | https://en.wikipedia.org/wiki/Indistinguishability%20obfuscation | In cryptography, indistinguishability obfuscation (abbreviated IO or iO) is a type of software obfuscation with the defining property that obfuscating any two programs that compute the same mathematical function results in programs that cannot be distinguished from each other. Informally, such obfuscation hides the implementation of a program while still allowing users to run it. Formally, iO satisfies the property that obfuscations of two circuits of the same size which implement the same function are computationally indistinguishable.
Indistinguishability obfuscation has several interesting theoretical properties. Firstly, iO is the "best-possible" obfuscation (in the sense that any secret about a program that can be hidden by any obfuscator at all can also be hidden by iO). Secondly, iO can be used to construct nearly the entire gamut of cryptographic primitives, including both mundane ones such as public-key cryptography and more exotic ones such as deniable encryption and functional encryption (which are types of cryptography that no-one previously knew how to construct), but with the notable exception of collision-resistant hash function families. For this reason, it has been referred to as "crypto-complete". Lastly, unlike many other kinds of cryptography, indistinguishability obfuscation continues to exist even if P=NP (though it would have to be constructed differently in this case), though this does not necessarily imply that iO exists unconditionally.
Though the idea of cryptographic software obfuscation has been around since 1996, indistinguishability obfuscation was first proposed by Barak et al. (2001), who proved that iO exists if P=NP is the case. For the P≠NP case (which is harder, but also more plausible), progress was slower: Garg et al. (2013) proposed a construction of iO based on a computational hardness assumption relating to multilinear maps, but this assumption was later disproven. A construction based on "well-founded assumptions" (hardness assumptions that have been well-studied by cryptographers, and thus widely assumed secure) had to wait until Jain, Lin, and Sahai (2020). (Even so, one of these assumptions used in the 2020 proposal is not secure against quantum computers.)
Currently known indistinguishability obfuscation candidates are very far from being practical. As measured by a 2017 paper, even obfuscating the toy function which outputs the logical conjunction of its thirty-two Boolean data type inputs produces a program nearly a dozen gigabytes large.
Formal definition
Let be some uniform probabilistic polynomial-time algorithm. Then is called an indistinguishability obfuscator if and only if it satisfies both of the following two statements:
Completeness or Functionality: For any Boolean circuit C of input length n and input , we have
Indistinguishability: For every pair of circuits of the same size k that implement the same functionality, the distributions and are computationally indistinguishable. In other words, for any probabilistic polynomial-time adversary A, there is a negligible function (i.e., a function that eventually grows slower than for any polynomial p) such that, for every pair of circuits of the same size k that implement the same functionality, we have
History
In 2001, Barak et al., showing that black-box obfuscation is impossible, also proposed the idea of an indistinguishability obfuscator, and constructed an inefficient one. Although this notion seemed relatively weak, Goldwasser and Rothblum (2007) showed that an efficient indistinguishability obfuscator would be a best-possible obfuscator, and any best-possible obfuscator would be an indistinguishability obfuscator. (However, for inefficient obfuscators, no best-possible obfuscator exists unless the polynomial hierarchy collapses to the second level.)
An open-source software implementation of an iO candidate was created in 2015.
Candidate constructions
Barak et al. (2001) proved that an inefficient indistinguishability obfuscator exists for circuits; that is, the lexicographically first circuit that computes the same function. If P = NP holds, then an indistinguishability obfuscator exists, even though no other kind of cryptography would also exist.
A candidate construction of iO with provable security under concrete hardness assumptions relating to multilinear maps was published by Garg et al. (2013), but this assumption was later invalidated. (Previously, Garg, Gentry, and Halevi (2012) had constructed a candidate version of a multilinear map based on heuristic assumptions.)
Starting from 2016, Lin began to explore constructions of iO based on less strict versions of multilinear maps, constructing a candidate based on maps of degree up to 30, and eventually a candidate based on maps of degree up to 3. Finally, in 2020, Jain, Lin, and Sahai proposed a construction of iO based on the symmetric external Diffie-Helman, learning with errors, and learning plus noise assumptions, as well as the existence of a super-linear stretch pseudorandom generator in the function class NC0. (The existence of pseudorandom generators in NC0 (even with sub-linear stretch) was a long-standing open problem until 2006.) It is possible that this construction could be broken with quantum computing, but there is an alternative construction that may be secure even against that (although the latter relies on less established security assumptions).
Practicality
There have been attempts to implement and benchmark iO candidates. In 2017, an obfuscation of the function at a security level of 80 bits took 23.5 minutes to produce and measured 11.6 GB, with an evaluation time of 77 ms. Additionally, an obfuscation of the Advanced Encryption Standard encryption circuit at a security level of 128 bits would measure 18 PB and have an evaluation time of about 272 years.
Existence
It is useful to divide the question of the existence of iO by using Russell Impagliazzo's "five worlds", which are five different hypothetical situations about average-case complexity:
Algorithmica: In this case P = NP, but iO exists.
Heuristica: In this case NP problems are easy on average; iO does not exist.
Pessiland: In this case, BPP ≠ NP, but one-way functions do not exist; as a result, iO does not exist.
Minicrypt: In this case, one-way functions exist, but secure public-key cryptography does not; iO does not exist (because explicit constructions of public-key cryptography from iO and one-way functions are known).
Cryptomania: In this case, secure public-key cryptography exists, but iO does not exist.
Obfustopia: In this case, iO is believed to exist.
Potential applications
Indistinguishability obfuscators, if they exist, could be used for an enormous range of cryptographic applications, so much so that it has been referred to as a "central hub" for cryptography, the "crown jewel of cryptography", or "crypto-complete". Concretely, an indistinguishability obfuscator (with the additional assumption of the existence of one-way functions) could be used to construct the following kinds of cryptography:
Indistinguishability obfuscation for programs in the RAM model and for Turing machines
IND-CCA-secure public-key cryptography
Short digital signatures
IND-CCA-secure key encapsulation schemes
Perfectly zero-knowledge non-interactive zero-knowledge proofs and succinct non-interactive arguments
Constant-round concurrent zero-knowledge protocols
Multilinear maps with bounded polynomial degrees
Injective trapdoor functions
Fully homomorphic encryption
Witness encryption
Functional encryption
Secret sharing for any monotone NP language
Semi-honest oblivious transfer
Deniable encryption (both sender-deniable and fully-deniable)
Multiparty, non-interactive key exchange
Adaptively secure succinct garbled RAM
Correlation intractable functions
Attribute-based encryption
Oblivious transfer
Traitor tracing
Graded encoding schemes
Additionally, if iO and one-way functions exist, then problems in the PPAD complexity class are provably hard.
However, indistinguishability obfuscation cannot be used to construct every possible cryptographic protocol: for example, no black-box construction can convert an indistinguishability obfuscator to a collision-resistant hash function family, even with a trapdoor permutation, except with an exponential loss of security.
See also
Black-box obfuscation, a stronger form of obfuscation proven to be impossible
References
Cryptographic primitives
Software obfuscation | Indistinguishability obfuscation | [
"Technology",
"Engineering"
] | 1,864 | [
"Cybersecurity engineering",
"Software obfuscation"
] |
66,325,847 | https://en.wikipedia.org/wiki/Robert%20Charles%20McMaster | Robert Charles McMaster (1913 – July 6, 1986 Delaware, Ohio), a pioneer in nondestructive testing, was Regents Professor Emeritus of Welding Engineering and Electrical Engineering at Ohio State University (OSU). He has more than 300 publications and 19 patents. He was awarded with the ASNT Gold Medal in 1977.
Education
McMaster earned a B.S. in 1936 in electrical engineering from Carnegie Mellon University; an M.S. in 1938 in electrical engineering and a Ph.D. in electrical engineering and physics in 1944 from California Institute of Technology. His Ph.D. research focused on the effects of light on power transmission lines.
Personal life
His daughter is novelist Lois McMaster Bujold.
ASNT Robert C. McMaster Gold Medal
The American Society for Nondestructive Testing has renamed its gold medal award in 1990 to honor Robert C. McMaster for his outstanding contributions to the NDT profession. The Robert C. McMaster Gold Medal Award recognizes individuals for outstanding contributions or significant advancement in any area of NDT and/or the Society.
References
1913 births
1986 deaths
American electrical engineers
American engineers
Carnegie Mellon University alumni
California Institute of Technology alumni
Ohio State University faculty
People from Delaware, Ohio | Robert Charles McMaster | [
"Materials_science"
] | 246 | [
"Nondestructive testing",
"Materials testing"
] |
66,326,711 | https://en.wikipedia.org/wiki/Adams%20resolution | In mathematics, specifically algebraic topology, there is a resolution analogous to free resolutions of spectra yielding a tool for constructing the Adams spectral sequence. Essentially, the idea is to take a connective spectrum of finite type and iteratively resolve with other spectra that are in the homotopy kernel of a map resolving the cohomology classes in using Eilenberg–MacLane spectra.
This construction can be generalized using a spectrum , such as the Brown–Peterson spectrum , or the complex cobordism spectrum , and is used in the construction of the Adams–Novikov spectral sequencepg 49.
Construction
The mod Adams resolution for a spectrum is a certain "chain-complex" of spectra induced from recursively looking at the fibers of maps into generalized Eilenberg–Maclane spectra giving generators for the cohomology of resolved spectrapg 43. By this, we start by considering the mapwhere is an Eilenberg–Maclane spectrum representing the generators of , so it is of the formwhere indexes a basis of , and the map comes from the properties of Eilenberg–Maclane spectra. Then, we can take the homotopy fiber of this map (which acts as a homotopy kernel) to get a space . Note, we now set and . Then, we can form a commutative diagramwhere the horizontal map is the fiber map. Recursively iterating through this construction yields a commutative diagramgiving the collection . This meansis the homotopy fiber of and comes from the universal properties of the homotopy fiber.
Resolution of cohomology of a spectrum
Now, we can use the Adams resolution to construct a free -resolution of the cohomology of a spectrum . From the Adams resolution, there are short exact sequenceswhich can be strung together to form a long exact sequencegiving a free resolution of as an -module.
E*-Adams resolution
Because there are technical difficulties with studying the cohomology ring in generalpg 280, we restrict to the case of considering the homology coalgebra (of co-operations). Note for the case , is the dual Steenrod algebra. Since is an -comodule, we can form the bigraded groupwhich contains the -page of the Adams–Novikov spectral sequence for satisfying a list of technical conditionspg 50. To get this page, we must construct the -Adams resolutionpg 49, which is somewhat analogous to the cohomological resolution above. We say a diagram of the formwhere the vertical arrows is an -Adams resolution if
is the homotopy fiber of
is a retract of , hence is a monomorphism. By retract, we mean there is a map such that
is a retract of
if , otherwise it is
Although this seems like a long laundry list of properties, they are very important in the construction of the spectral sequence. In addition, the retract properties affect the structure of construction of the -Adams resolution since we no longer need to take a wedge sum of spectra for every generator.
Construction for ring spectra
The construction of the -Adams resolution is rather simple to state in comparison to the previous resolution for any associative, commutative, connective ring spectrum satisfying some additional hypotheses. These include being flat over , on being an isomorphism, and with being finitely generated for which the unique ring mapextends maximally.
If we setand letbe the canonical map, we can setNote that is a retract of from its ring spectrum structure, hence is a retract of , and similarly, is a retract of . In additionwhich gives the desired terms from the flatness.
Relation to cobar complex
It turns out the -term of the associated Adams–Novikov spectral sequence is then cobar complex .
See also
Adams spectral sequence
Adams–Novikov spectral sequence
Eilenberg–Maclane spectrum
Hopf algebroid
References
Algebraic topology
Homological algebra
Topology | Adams resolution | [
"Physics",
"Mathematics"
] | 824 | [
"Mathematical structures",
"Algebraic topology",
"Fields of abstract algebra",
"Topology",
"Space",
"Category theory",
"Geometry",
"Spacetime",
"Homological algebra"
] |
66,326,908 | https://en.wikipedia.org/wiki/Marinimicrobia | Marinimicrobia is a candidate phylum of bacteria, previously known as SAR406, MGA or Marine Group A. They have been found mainly at great depths such as the Challenger Deep, the Mariana Trench, and the Puerto Rico Trench. This phylum has a low representation in shallow pelagic samples and high abundance in deep samples. Although these bacteria are often associated with low dissolved oxygen environments, very little is known about their ecology and metabolic functions. Marinimicrobia form part of the FCB group along with other related bacterial phyla.
References
Bacteria phyla | Marinimicrobia | [
"Biology"
] | 122 | [
"Bacteria stubs",
"Bacteria"
] |
66,327,069 | https://en.wikipedia.org/wiki/Abditibacteriota | Abditibacteriota is a bacterial phylum previously known as FBP candidatus, which is widespread in extreme environments on Earth, from polar and desert ecosystems to wastewater and contaminated mining sites. The first cultured representative came from Utsteinen in the Sør Rondane Mountains (East Antarctica) and is a chemoheterotrophic, gram-negative, aerobic and oligotrophic bacterium. It has a limited number of carbon sources, optimized metabolism for survival in low nutrient habitats. Extreme resistance against antibiotics and toxic compounds was identified. Phylogenetically, it would be related to the phylum Armatimonadota according to molecular analysis.
References
Bacteria phyla | Abditibacteriota | [
"Biology"
] | 147 | [
"Bacteria stubs",
"Bacteria"
] |
66,327,755 | https://en.wikipedia.org/wiki/Ardei | Ardei is a possibly-paraphyletic suborder of order Pelecaniformes that include the families Ardeidae (herons, egrets, and bitterns) and Threskiornithidae (ibises and spoonbills). Traditionally the ardeids and threskiornithids were classified in the order Ciconiiformes along with Ciconiidae (storks), Phoenicopteridae (flamingos), Scopidae (hamerkop), Balaenicipitidae (shoebill), and even Cathartidae (New World vultures and condors). However, there were some osteological studies that have questioned the monophyly of Ciconiiformes, suggesting that the ardeids and threskiornithids originated from early gruiforms, with the latter being a transitionary taxon to order Charadriiformes. The non-monophyletic nature of Ciconiiformes is supported by recent genomic studies that have found support for threskiornithids, ardeids, scopids and balaenicipitids being closely related to Pelecanidae (pelicans).
The exact relationship between ardeids, threskiornithids and suborder Pelecani is still being investigated with two hypotheses. One hypothesis is ardeids and threskiornithids are each other's sister taxon in suborder Ardei (as presented here). The other hypothesis is the ardeids are the sister taxon to the pelecanid-related clade, with threskiornithids the basal most group. This hypothesis is supported from some morphological and the earliest representations of non-threskiornithid pelecaniforms come from the Oligocene deposits in Africa, while threskiornithids have been found in Eocene deposits of North America and Europe.
References
Paraphyletic groups | Ardei | [
"Biology"
] | 417 | [
"Phylogenetics",
"Paraphyletic groups"
] |
66,328,046 | https://en.wikipedia.org/wiki/CO2SYS | CO2SYS is a family of software programs that calculate chemical equilibria for aquatic inorganic carbon species and parameters. Their core function is to use any two of the four central inorganic carbon system parameters (pH, alkalinity, dissolved inorganic carbon, and partial pressure of carbon dioxide) to calculate various chemical properties of the system. These programs are widely used by oceanographers and limnologists to understand and predict chemical equilibria in natural waters.
History
Chemical equilibria in marine and freshwater systems were calculated according to various conventions for most of the 20th century, which led to discrepancies among laboratories' calculations and limited scientific reproducibility. CO2SYS was first published by Ernie Lewis and Doug Wallace in 1998 as a DOS-interface program written in QBasic. Subsequent developments have included several MATLAB implementations, two Microsoft Excel templates, a Python package "PyCO2SYS", and an R package inspired by CO2SYS, "seacarb". Development of the various CO2SYS programs continues as of 2021 with the addition of more chemical equilibrium parameters and compatibility with a wider range of environments, e.g. anoxic waters.
Chemical Overview
The aquatic inorganic carbon system is composed of the various ionic, dissolved, solid, and/or gaseous forms of carbon dioxide in water. These species include dissolved carbon dioxide, carbonic acid, bicarbonate anion, carbonate anion, calcium carbonate, magnesium carbonate, and others. The relative amounts of each species in a body of water depends on physical variables including temperature and salinity, as well as chemical variables like pH and gas partial pressure. Variables like alkalinity and dissolved (or total) inorganic carbon further define a mass and charge balance that constrains the total state of the system.
Given any two of the four central inorganic carbon system parameters (pH, alkalinity, dissolved inorganic carbon, partial pressure of carbon dioxide) the remainder may be derived by solving a system of equations that adhere to the principles of chemical thermodynamics.
References
Chemistry software | CO2SYS | [
"Chemistry"
] | 429 | [
"Chemistry software",
"nan"
] |
66,330,633 | https://en.wikipedia.org/wiki/Imo.im | imo is a proprietary audio/video calling and instant messaging software service. It allows sending music, video, PDFs and other files, along with various free stickers. It supports encrypted group video and voice calls with up to 20 participants. According to its developer, the service possesses over 200 million users and over 50 million messages per day are sent through it.
History
The product was created as a web-based application in 2005 for accessing multiple chat platforms, including Facebook Messenger, Google Talk, Yahoo! Messenger, and Skype chat. It was developed by Pagebites, which is a subsidiary of Singularity IM, Inc. and required a subscriber's phone number to verify the users' account. In March 2014, support for all third-party messaging networks ended.
In January 2018, the app reached 500 million installs.
imo.im has implemented end-to-end encryption for its chats and calls, ensuring that the conversations remain private between the sender and receiver.
See also
List of social platforms with at least 100 million active users
References
External links
Mobile applications
Android (operating system) software
IOS software
Windows instant messaging clients
Cross-platform software
Instant messaging clients
Social media
2007 software | Imo.im | [
"Technology"
] | 249 | [
"Instant messaging",
"Mobile content",
"Instant messaging clients",
"Social software"
] |
66,330,773 | https://en.wikipedia.org/wiki/Sriwijaya%20Air%20Flight%20182 | Sriwijaya Air Flight 182 was a scheduled domestic passenger flight from Jakarta to Pontianak, Indonesia. Five minutes after departing from Soekarno–Hatta International Airport on 9 January 2021, the Boeing 737-500 experienced an upset and crashed into the Java Sea off the Thousand Islands, killing all 62 people on board. A search of the area recovered wreckage, human remains, and items of clothing. The flight data recorder (FDR) was recovered on 12 January, and the data storage module of the cockpit voice recorder was recovered on 30 March. Flight 182 is the third deadliest accident involving a Boeing 737-500 after Aeroflot Flight 821 and Asiana Airlines Flight 733, and was the deadliest plane crash in 2021.
During the search, Indonesia's National Transportation Safety Committee (NTSC) used the available data from Flightradar24, and hypothesised that the plane's engines were still operating upon impact. It was known that the autothrottle on this aircraft had malfunctioned a few days earlier, and one line of investigation was whether this might have contributed to the accident.
A preliminary report released on 10 February 2021 suggested problems with the plane's autothrottle; the thrust lever for the left engine reduced thrust as the aircraft climbed, while the thrust lever for the right engine remained fixed. On 10 November 2022, the NTSC published the final report of the investigation, concluding that the crash had been caused by a combination of a faulty autothrottle and pilot error.
Background
Aircraft
The aircraft involved was a Boeing 737-524, registered as PK-CLC ( 27323, Line no.2616). It was equipped with two CFM International CFM56-3B1 engines. At the time of the accident, the aircraft had accumulated 62,983 hours and 40,383 cycles.
The aircraft was manufactured in 1994, and had its maiden flight on 13 May 1994. It was first delivered to Continental Airlines on 31 May 1994 under the registration N27610. The aircraft was transferred to United Airlines in 2010 after Continental and United merged. On 15 May 2012, the aircraft was sold to Sriwijaya Air. It was the first of a total of fifteen 737-500s received by Sriwijaya Air in 2012 to replace their 737-200s. Sriwijaya Air named the aircraft Citra.
Between March and December 2020, the aircraft was stored at Surabaya Juanda International Airport due to reduced demand for air travel during the coronavirus pandemic. The Ministry of Transportation stated that it inspected the aircraft on 14 December 2020 and issued a new certificate of airworthiness on 17 December 2020. It resumed service on 19 December 2020.
Passengers and crew
There were 62 people on board, of which 50 were revenue passengers (43 adults and 7 children). Of the 12 crew members, six were operating crew on the flight, while the other six were deadheading as passengers. The majority of the passengers were residents from West Kalimantan.
Among the passengers were Mulyadi Tamsir, a politician from the People's Conscience Party (Hanura) and chairman of the Indonesian Muslim Student Association (PB HMI).
The crew on the flight consisted of Captain Afwan, 54, who had over 17,904 hours of flight experience, 9,023 hours of them on the Boeing 737, First Officer Diego Mamahit, 34, who had over 5,107 hours of flight experience, 4,957 hours of them on the Boeing 737, and four flight attendants. Afwan was a former pilot in the Indonesian Air Force.
The six deadheading crew and several revenue passengers had transferred to Flight 182 from an earlier NAM Air flight that did not operate.
Flight timeline
Flight 182 was scheduled to depart from Soekarno–Hatta International Airport at 13:40 WIB (06:40 UTC), and to arrive at Supadio International Airport in Pontianak, West Kalimantan, at 15:00 WIB (08:00 UTC). Departure was delayed by monsoon rains, and Flight 182 took off from runway 25R at 14:36 local time (07:36 UTC). Due to the delay, it was expected to land in Pontianak at 15:50 WIB (08:50 UTC).
The aircraft departed on a standard instrument departure with a clearance to climb to . During its climb, Flight 182 went off course to the northwest. ATC asked the crew about the deviation and got no response. A few seconds later, the aircraft dropped off radar.
After being instructed by the ATC to stop climbing to , Captain Afwan lowered the target altitude and entered it into the autopilot. To compensate for the altitude decrease, as descending would cause an increase in airspeed, the autothrottle moved the levers back, to maintain the intended airspeed. The left lever moved backwards, while the right lever stayed in place due to the opening of the torque switch.
The aircraft was in a right turn, but as the left lever kept decreasing while the right lever was still at maximum climb power, thrust asymmetry forced the aircraft to start turning to the left. In order to maintain the heading, the autopilot tried to keep the aircraft in a right turn. The autopilot eventually banked the aircraft to the right with a bank angle of 19 degrees, the maximum allowed by the autopilot. The thrust asymmetry continued to increase until it overpowered the autopilot. The amount of asymmetry reached a dangerous level and the aircraft started to bank to the left, with the bank angle increasing by one degree per second. The pilots apparently did not notice the change of the aircraft's bank angle, as they were busy with other procedures.
The left lever kept reducing until it reached the idle stop position, causing the left bank angle to increase more quickly than before. The pilots had just received an instruction from ATC to climb to when the aircraft's alarm activated, warning the crew about the 37 degree left bank. Surprised, Captain Afwan grabbed his control column, disengaged the autopilot and tried to recover the aircraft. His input, however, worsened the bank angle, as he turned the aircraft further to the left for four seconds.
Before the autopilot was disconnected, it had been preventing the aircraft from overbanking to the left. As it was disconnected, the crew lost any protection from the autopilot. With Captain Afwan's left turn input, the aircraft banked through its maximum allowable bank angle and rolled through 90 degrees to the left. The nose then dropped and the aircraft rapidly descended towards the Java Sea below, inverted. First Officer Mamahit shouted to Captain Afwan regarding the bank angle, warning him that the aircraft had just entered an upset condition. Realizing his mistake, Captain Afwan pulled the yoke back and attempted to recover from the dive. Due to being inverted, the aircraft descended faster and his action led to an increased rate of descent. Flightradar24 reported that four minutes after takeoff, the aircraft dropped by in less than a minute. According to AirNav Radarbox flight data, the aircraft reported that the climb phase of the flight was interrupted by a rapid drop in altitude from at 07:40 UTC.
Captain Afwan managed to nearly level the wings and raise the nose up to 0°, but by then there was no more room for recovery as the altitude was too low and the aircraft was in overspeed condition. The aircraft crashed belly-first into the Java Sea near Laki Island and from Soekarno–Hatta International Airport. There were no survivors. According to the ATC, there was no distress call during the flight.
Search and recovery
The crash site was located from Soekarno-Hatta International Airport.
Personnel from a vessel provided by the Ministry of Transportation reported that body parts, fragments of clothing, electronics, personal belongings and wreckage had been recovered from the sea in waters near the Thousand Islands, with aviation fuel also reported around the location. The water near the crash site has a depth of around .
The National Search and Rescue Agency () immediately deployed personnel to the crash site while the National Police and the Ministry of Transportation set up crisis centres in Port of Tanjung Priok and Soekarno–Hatta International Airport. The Indonesian Navy deployed a number of vessels for the search and rescue operations, in addition to helicopters and KOPASKA (frogman) personnel.
The Indonesian government requested assistance from the South Korean government with the search. Through the Korea - Indonesia Marine Technology Cooperation Research Center (MTCRC), the South Korean Ministry of Oceans and Fisheries deployed a research vessel equipped with a detector to Indonesia. At least 15 personnel from MTCRC were also sent. The Singaporean government also provided assistance in the search.
Rescuers recovered a life vest, pieces from the aircraft's fuselage, and a destroyed wheel rim from the Boeing 737. Most of the wreckage was found at a depth of .
On the night of 9 January, an emergency slide from the aircraft was recovered from the waters near Lancang Island, Thousand Islands. The scattered debris and the small pieces of the wreckage indicated a high-speed impact. Much more wreckage was found over the next few days.
The Indonesian Navy pinpointed the exact coordinates of the crash site on 10 January, and the flight data recorder was retrieved two days later. The casing of the cockpit voice recorder was recovered on 15 January but the data storage module inside was missing. In the afternoon of 17 January, the CVR components and its casing, but without the data storage module, were handed over to the NTSC for further examination. The next day on 18 January, the search for the CVR, wreckage, and victims was extended for three more days.
On 21 January BASARNAS announced the search for victims and aircraft debris had been halted. A total of 122 pieces of debris had been recovered from the crash site, including one of the engine turbines. The search for the data storage module of the CVR continued until it was dredged up from the seabed on 30 March.
Investigation
The NTSC was immediately notified of the accident, with assistance from BASARNAS. NTSC stated that starting on 10 January 2021, just before 06:00 local time, search and rescue personnel would start searching for the aircraft's flight recorders. It added that the investigation will be assisted by the United States' National Transportation Safety Board (NTSB), with the Singaporean Transport Safety Investigation Bureau also offering assistance with the investigation. On 10 January, NTSC obtained raw data of the aircraft's flight path from radar and interviews with the air traffic controller. Investigators also retrieved the transcript of communications between the pilots and ATC.
Weather data retrieved from the Meteorology, Climatology, and Geophysical Agency (BMKG) confirmed the presence of moderate to heavy rain during takeoff with chance of thunderstorms reported. The data later showed that a high cumulonimbus cloud was present around Soekarno-Hatta International Airport with the minimum temperature of the cloud tops at , prompting speculation that the aircraft had encountered turbulence. Visibility was reported to be . Analysis by the Indonesian National Institute of Aeronautics and Space (LAPAN) showed that weather conditions were not extreme. LAPAN stated that a meso-convective system had been formed near the Java Sea at 11:00 WIB (04:00 UTC), but the system had already dissipated by the time Flight 182 took off. According to NTSC, there was no indication that there would be any significant cloud on the aircraft's flight route. NTSC confirmed, however, that the pilots had contacted Jakarta ATC to change its heading to 075 degrees due to bad weather.
An investigator with NTSC stated that based on the distribution of the debris, the aircraft possibly ruptured when it hit the water. Combining Flightradar24 data and the shape of the engine turbine's fan blade and turbine disc, NTSC speculated that the aircraft's engines were still operating upon impact; based on the evidence, the aircraft was still responsive at .
There was a public concern that the aircraft was not airworthy. The Federal Aviation Administration initially had issued an Airworthiness Directive to Boeing 737-500 operators concerning fatigue cracking on the left nacelle support overwing fitting flange fastener hole. The director of Sriwijaya Air, Jefferson Irwin Jauwena, insisted that the aircraft was airworthy. Moreover, the Ministry of Transportation later examined the aircraft's airworthiness and determined that the aircraft was safe to fly.
An Indonesian aviation expert said that the aircraft had been stored for repairs by Sriwijaya Air between 23 March and 23 October 2020. However, other experts speculated that the long time spent inactive may have caused deterioration and that technical problems may have developed.
On 15 January 2021, NTSC announced that the data from the FDR have been successfully downloaded. A total of 330 parameters were being examined and analysed by investigators. A Reuters report said that the data extracted, such as flight path, speed and engine condition, were "in good condition."
The preliminary report was released on 10 February 2021.
On 12 April 2021, the NTSC announced that all data from the CVR was successfully downloaded and included the accident flight.
The investigation conducted simulations of the accident based on the FDR and CVR data in flight training simulator. The first simulation attempt was conducted at the Las Vegas Flight Academy in Henderson, Nevada, on 27 October 2021. It was found that the simulator did not react similarly to the accident flight during an asymmetric thrust event. The simulation revealed that the thrust lever console was not closely monitored by the pilots. The investigation repeated the simulation session in NAM Training Center in Jakarta on 7 December 2021 and successfully recreated the accident flight. However, some objectives could not be achieved due to the difference in configuration between the simulator and the accident aircraft.
On 17 January 2022, the NTSC released its first interim statement.
Maintenance issue
According to Tempo magazine, sources close to the investigation committee revealed that the aircraft involved in the accident had a recurring autothrottle problem for at least a month. NTSC, however, stated that they did not have the maintenance data yet. According to a person familiar with the investigation, "the autothrottle was producing more thrust in one of the two jet engines" during the flight. If pilots did not set the power manually, "an aircraft could turn to the side or even make an abrupt descent." On 22 January it was revealed that a malfunction of the autothrottle system had been reported several days before the flight; the aircraft can fly without the system, however, as the pilot can set the throttles manually.
The investigation was focused on the faulty autothrottle system as multiple parameters from the FDR indicated that an abnormality had occurred in the system. NTSC later stated that the committee had sent 13 aircraft components, including the aircraft's autothrottle system, to United States and United Kingdom for further examination.
The maintenance logbook of the aircraft revealed that there had been recurring problems on the Mach/Airspeed indicator and the auto-throttle system of the aircraft. The Mach/Airspeed indicator was eventually replaced on 4 January, while the auto-throttle system was fixed on 5 January. The FDR data, however, confirmed that the auto-throttle had malfunctioned again on 9 January, the day of the accident. While the aircraft was climbing through 10,000 ft, the left engine thrust lever continued to decrease, while the thrust lever on the right engine remained in place. When the aircraft reached 10,000 ft, an aircraft upset happened. The autopilot disengaged and the aircraft rolled to the left with a bank angle of more than 45 degrees. A few seconds later, the auto-throttle then disengaged.
A further check of the logbook confirmed that the problematic autothrottle system had been reported multiple times by pilots of Sriwijaya Air. The problems had been reported as many as 65 times with the first report being made on 7 November 2013, nearly eight years before the crash. Issues regarding the autothrottle ranged from the inability of the autothrottle to engage and disengage during flight, inability of the autothrottle to hold the "Armed" position during flight, and systemic malfunction on the autothrottle altogether. Out of all 65 complaints, approximately 32 of them were related to unintended disengagement of the autothrottle in mid-flight. Pilots also filed as many as 69 reports regarding problems with the autopilot in addition to the autothrottle problems. There were also 61 complaints related to differences in engine parameters reading, all of which occurred throughout the aircraft's operation with Sriwijaya Air.
Attempts to rectify the issues had been made multiple times by engineers. Several engineers decided to troubleshoot the system in accordance with the written manual, while a majority of them tried to fix the problems by simply cleaning the electrical connector of the autothrottle components. After they completed the cleaning, the engineers would run tests with the built-in test equipment (BITE). In every case, the BITE test showed that there were no faults remaining. However, as the issue continued to appear despite multiple cleaning attempts, it was clear that the problems were not caused by dirty cable connectors.
Although there was a wide range of problems with the autothrottle systems, during the 9 January accident flight the problem that occurred on board was a difference in the engine parameter readings showing distinctly different thrust lever positions as the left lever continued to move backwards while the right lever stayed in position. Normally, both levers move simultaneously to prevent thrust asymmetry from occurring. The frozen-in-place right lever was particularly noted by investigators as there were multiple reports of the same problem on earlier flights. These included reports of difficulties in moving the right lever and also lack of robust response from that lever.
As the right lever in the accident flight did not move back simultaneously with the left lever, it was suspected that the source was related to friction forces in the thrust control cable. The connection between the servo motor and the thrust levers was suspected as the source of this problem, indicating a possible weak linkage between both components. The high friction forces eventually tripped the autothrottle torque switch, a feature that allows the pilots to override the autothrottle command. As the torque switch was accidentally opened, the autothrottle could not provide input to the lever and the lever eventually stopped moving in its track. Since it was only the right lever that had high friction and weak linkage, the left lever continued to move backwards, as the autothrottle was not overridden.
Although the linkage between the servo motor and the thrust lever could not be recovered due to the severity of the impact, this theory was deemed to be the most plausible cause of the problem with the right lever, as evidence from other tests did not support other hypotheses.
Thrust asymmetry
In most airliners, a thrust asymmetry would be detected by the aircraft's safety system, which would have immediately deactivated the autothrottle, but the accident aircraft's system did not operate correctly.
Reports of multiple thrust asymmetry incidents involving the engagement of the autothrottle led the Federal Aviation Administration (FAA) to issue a mandatory directive regarding the installation of a safety feature, the Cruise Thrust Split Monitor (CTSM), in 2000. The CTSM was responsible in deactivating the engaged autothrottle if a thrust asymmetry had indeed occurred in mid-flight. Activating it, however, was a little bit intricate. The system required a set of criteria before it was able to be activated. These were the position of the levers where the computers should detect significant difference between both levers, an engaged autothrottle which was not in the go-around mode, and the last was the position of the flight spoilers, which must be deflected by more than 2.5 degrees for at least 1.5 seconds. The reason for the system to measure the flight spoiler angle was that deflecting spoilers would indicate that the asymmetry was unwanted, and the nature of the emergency was real.
Based on the available data, the condition aboard the 9 January flight had actually met all the requirements for CTSM activation, yet the autothrottle did not disengage until later in the flight. The FDR recording showed that the CTSM system activated while the aircraft was diving towards the sea, instead of earlier during the climb, when the asymmetry had appeared for the first time. By the time the CTSM became active, the pilots had lost their control of the aircraft.
After a review of the aircraft's QAR (Quick Access Recorders), a system established by Sriwijaya Air to regularly download the content of flight recorders for monitoring purposes, it was discovered that the anomaly had happened to other flights before the crash. One flight was particularly noted for its striking similarities. On 15 March 2020, the flight suffered the same scenario with the 9 January flight. The left lever managed to move back, while the right lever stayed in place, creating a thrust asymmetry that caused the aircraft to be pulled to the left. Fighting to maintain the course, the autopilot turned the yoke to the right and put the aircraft to the maximum allowed bank angle that could be commanded by the autopilot. The pilots were initially unaware of the anomaly and the autopilot kept fighting the unwanted turn until it got overpowered by the asymmetric thrust. In the 15 March incident, however, both pilots became aware of the situation and successfully recovered the aircraft. In spite of the seriousness of the incident, neither pilot reported the incident to Sriwijaya Air. Investigation revealed that the commander of the aircraft during the 15 March incident was Captain Afwan, the same pilot of the 9 January flight, though he was not the pilot flying.
The investigation eventually stated that the most plausible cause of the delayed activation of the CTSM was due to the low signal value that had been emitted by the spoiler position sensor, specifically on the right side. This was evidenced by the timing of the authothrottle disengagement, which happened immediately after Captain Afwan commanded a bank angle over 19 degrees, the maximum allowable input for the autopilot. Prior to the disengagement, the autopilot made an input of 19 degrees to the right. Even though that condition had met all the required criteria for the activation of the CTSM, the autothrottle was still engaged as the signal that the CTSM had been receiving was lower than 2.5 degrees of spoiler deflection, causing it to not activate. After Captain Afwan added another bank angle input, which was greater than the allowed autopilot command, the signal sent a spoiler deflection value of greater than 2.5, causing the CTSM to turn on and disengaging the autothrottle. This was further proven by the fact that the exact same thing had happened during the 15 March incident. On that flight, the pilot also made an input greater than the allowed maximum bank angle that the autopilot could command, causing the CTSM to activate and disconnect the autothrottle.
The source of the failure, however, could not be pinpointed by investigators as they could not recover the essential components. They suspected that the aircraft might have either suffered an erroneous spoiler sensor, damaged spoiler linkage or improperly rigged sensor. Sriwijaya Air stated that they had never rigged the flight spoiler sensor as there was lack of requirement to inspect the sensor and that they had never had a requirement to do so.
Pilot error
Even though the aircraft had difficulties with the autothrottle system, this alone was not severe enough to cause the crash, as pilots are supposed to have been trained to handle these kinds of situations. The thrust asymmetry that occurred on board was a subtle but progressive failure that should be noticed by pilots, as there was enough time for the pilots to be aware of the evolving situation. The aircraft also should not have entered an upset condition. Other than the autothrottle and systems related to the aircraft's automation, the maintenance logbook indicated that there were no known defects on the other vital components such as the attitude indicator.
During the flight, the aircraft started to head off course by banking to the left instead of the right. While climbing past 10,450 feet, the wing position changed from right turn to level position. After rolling through the level position, the left wing began to sink further. For a period of 6 seconds, the bank angle increased to 7 degrees to the left. Normally, this would have been immediately noticed by the crew, but the pilots did not react until the bank angle warning began to sound several seconds later, indicating that the bank angle had exceeded the safe limit. The pilots had enough time to recognize this condition. Had the pilots actively monitored the attitude indicator and maintained situational awareness they would have immediately corrected the bank angle.
NTSC identified several factors that might have influenced the pilots' decreased situational awareness during the flight. Among the first was the fact that the aircraft was flying into clouds, based on the communication between ATC and the crew, as well as weather data from the area of the crash. The pilots had informed ATC about their intention to change heading due to the presence of storm system on their route. The Indonesian meteorology office, BMKG, stated that the visibility at the time was around 6 - 10 km and that it was cloudy. It is likely that they were operating in cloud, requiring an upset recovery on instruments.
Despite the lack of external visual cues, the onboard electronic attitude indicator was functioning normally and could still be used as reference. The investigation suspected that the pilots might have become too reliant on the autopilot system. After pressing the autopilot button, the autopilot turned the yoke to the right, heading to the correct course of the flight. By seeing the yoke that was turning to the right, the pilots assumed that the aircraft was also banking to the right. The pilots thought that the autopilot was working as intended and thus decided to turn their attention to other procedures, such as communication and altitude. The importance of monitoring their route and attitude were ignored, as they thought that the autopilot and autothrottle were operating normally. The phenomenon was described as confirmation bias. Meanwhile, as the asymmetry progressed, the autopilot could not turn the yoke further and eventually became overpowered.
By not monitoring the attitude of the aircraft, the aircraft turned to the left unnoticed until its warning system alerted the crew about the dangerous bank angle. In order to level the aircraft, Captain Afwan should have turned the yoke to the right. Instead, he turned the yoke further to the left. Apparently, as the autopilot had been turning the yoke to the right, Captain Afwan thought that the aircraft was banking dangerously to the right and instinctively turned the yoke to the left. His input eventually caused the aircraft to enter an upset condition with a bank angle of more than 90 degrees. Captain Afwan eventually made the situation worse by pulling the nose up even though the wings were not levelled, causing the aircraft to dive towards the ocean with a rate of descent of at least 45,000 ft per minute. With little room for recovery, the crew could not prevent the aircraft from impacting the water.
The discovery of Captain Afwan's failure in a basic skill such as the Upset Prevention and Recovery Training (UPRT) sparked concern and a more detailed investigation into the training program that he had been following during his career. The examination noted that he had undergone an upset and recovery training in May 2019, as part of a mandatory training implemented by Sriwijaya Air, with the result being described as "satisfactory". There were several notes regarding the need to improve on certain areas, such as standard callouts and several other procedures.
The investigation further discovered that the UPRT training that the crew had taken for the flight was lacking in detail, leading the NTSC to investigate the training system at Sriwijaya Air further.
Safety culture
While there were some shortcomings in Captain Afwan's personal skill as a pilot, the investigation into the training of pilots and the maintenance management in Sriwijaya Air led to the discovery of larger problems regarding the safety culture within the company.
Following the discovery of subpar training within the airline's syllabus, NTSC opted to conduct a first-hand inspection of the pilot training related to upset and recovery at the Sriwijaya Air training centre. While observing the pre-simulator briefing, it was revealed that Sriwijaya Air had modified some of the standard callouts, such as the "nose low upset" to "upset brown" and "nose high upset" to "upset blue". They also had modified some of the standard procedures for an upset recovery by adding additional irrelevant tasks for the pilot monitoring (PM) during the recovery, including the requirement for pilots to announce an upset condition and to initiate mayday calls before assisting the pilot flying (PF). These modifications were adopted without prior consultation with the Indonesian aviation authorities. During the session, the training instructor failed to emphasize certain steps and did not explain its importance. The instructor also missed several important training points, such as common mistakes in upset recovery, recommended strategies for aircraft upset and could not explain the importance of upset and recovery training to the NTSC.
The simulation of the upset and recovery training further showed deficiencies in the quality of Sriwijaya Air's pilot training. Due to the addition of irrelevant tasks to the PM during upset recovery attempt, the PM could not assist the PF in monitoring crucial information such as the aircraft's airspeed and altitude. In one of the training sessions, the trainee caused the aircraft to enter an accelerated stall condition, due to improper action during recovery. The instructor eventually had to intervene to correct their mistakes.
Looking further into UPRT in Indonesian aviation industry, the investigation found that there was also problem with the national implementation of the UPRT. Despite being made mandatory in 2017, the UPRT requirements were not explained in detail and the national standard had not been used as guidance or as a reference for airlines to use. Investigators stated that this might have contributed to Sriwijaya Air's inadequate and ineffective UPRT program.
Other than the training, the NTSC also pointed out other deficiencies within Sriwijaya Air's safety and maintenance management system. Review of the aircraft's maintenance logbook revealed that the autothrottle issue had never appeared until the aircraft was acquired by Indonesia's Sriwijaya Air. When it did appear, the engineer did not rectified it properly. The repeated use of BITE tests alone were indicative of a problematic maintenance culture within the airline. The NTSC stated that this practice was used by the engineers because it was thought to be easy, but by doing so it didn't eliminate the root-cause of the defect. Sriwijaya Air had already put a system in place to make sure that maintenance practices would be reviewed and monitored regularly to prevent recurring defects. The involved aircraft, however, suffered the exact same defects for nearly eight years, proving that there was lack of supervision of maintenance practices within Sriwijaya Air.
The NTSC also noted the pilots' action after the 15 March 2020 incident, in particular that they did not report the incident to Sriwijaya Air. The incident was regarded by the NTSC as serious, but both pilots failed to report it and did not write up the technical difficulties during the flight in the maintenance logbook. This same pattern was also discovered with the other pilots during the other thrust asymmetry incidents. Despite the seriousness, none of the pilots had reported the incidents to Sriwijaya Air.
To ensure that the prevailing safety procedures were followed properly, Sriwijaya Air had established the Flight Data Analysis Program (FDAP), which was responsible for monitoring events that were critical to the safety of the flight. Among those monitored were incidences of excessive bank angle and thrust asymmetry. FDAP would analyze the problems after receiving reports from the crew. NTSC, however, stated that the hazard-reporting system had not been well implemented or emphasized to each Sriwijaya Air employee. Reviews of the reports that had been received from the FDAP revealed that the majority of the reports had been made by ground personnel, while pilots rarely reported aircraft technical difficulties. Flight dispatchers had never filed any reports to the FDAP.
Sriwijaya Air safety management was criticized in the findings. The airlines' Quality, Safety and Security Department (QSS) was noted as having failed in its role. An assessment in November 2019 managed to identify nine out of 10 risks that were deemed "intolerable". The NTSC investigation suggested that, even after two years, there had been no attempt to reduce any of the nine intolerable risks to a tolerable level.
The investigation concluded that there had been inadequate implementation and multiple issues related to safety management in Sriwijaya Air, which contributed to the crash of Flight 182.
Final report
The final report was published on 10 November 2022. It concluded that the crash had been caused by asymmetrical thrust setting due to a faulty autothrottle system. A feature central to the immediate deactivation of the autothrottle, the Cruise Thrust Split Monitor (CTSM), failed to work properly due to signal interference from the aircraft's spoilers, causing the thrust asymmetry to increase. The aircraft turned left instead of right as intended and eventually entered an upset condition. Lack of upset and recovery training contributed to the pilots' inability to prevent and recover from the upset condition.
Responses
Immediate aftermath
In the immediate aftermath of the accident, the state's insurance company Jasa Raharja announced that it would compensate the relatives of the passengers and crew members aboard Flight 182. Each next-of-kin of the deceased would receive Rp 50 million (US$). Minister of Social Affairs Tri Rismaharini announced that her ministry would give Rp 15 million (US$) for each victim for compensation.
Delegations from Indonesia's House of Representatives visited the operation centre in Tanjung Priok. They later announced that the House would hold talks with the Ministry of Transportation about the accident. They also stated that they would hold talks with BMKG, Sriwijaya Air and NTSC. The Indonesian House of Representatives will scrutinize the operation of conduct of the Indonesian Ministry of Transportation regarding supervision of airliners' compliance with the aircraft's maintenance manual. A full evaluation of every airliner in Indonesia was later ordered.
Memorial
The Regent of Thousand Islands, Junaedi, stated that the government of Thousand Islands will build a monument dedicated to the victims of Flight 182 on Lancang Island. On 22 January 2021, family and loved ones of the victims were invited to spread flowers approximately where the plane had crashed. Prior to the event, the director of Sriwijaya Air expressed condolences to the victims.
Aviation safety
The crash of Flight 182 and the subsequent investigation brought the safety of Indonesian aviation under scrutiny, highlighting the poor safety record of the nation's aviation industry. With 697 fatalities in the past decade alone, the Aviation Safety Network stated that Indonesia had the deadliest aviation market in the world.
During the course of the investigation, Sriwijaya Air attempted to improve several company operational areas. Prior to the publication of the interim report, the airline included a more thorough UPRT program in the pilot training syllabus and disseminated the Boeing Flight Operation Technical Bulletin regarding UPRT, improved recurrent engineer training, revised the current Flight Data Analysis system, and performed further evaluations in other areas that had been deemed insufficient by investigators. Following the publication of the interim report, the airline gave further updates on the progress of their UPRT program, performed thorough autothrottle and spoiler inspections on the airline's Boeing 737 fleet, and also revised the company's FDAP and maintenance manual.
The findings related to UPRT prompted the Indonesian government to set up a task force for UPRT implementation. On 25 June 2021, the government approved the formation of the task force. The task force was assigned the creation of guidance, regulations, and implementation of UPRT throughout Indonesia, including consultations with internationally recognized experts on the matter. The implementation plan was successfully reviewed on 8 October and the proposed UPRT plan was completed by 21 October 2021.
In the aftermath of the crash, Boeing issued a technical direction on the possible failure on the wiring of the aircraft's flap indication system and the aircraft's related autothrottle system. Operators of the affected aircraft were mandated to conduct an inspection on their aircraft's autothrottle and wiring of the flap indication system within 250 hours after the issuance of the directive. The FAA then followed Boeing's bulletin and issued an airworthiness directive related to the findings. Boeing later announced that they would develop a service bulletin to provide additional guidance related to flap inspection.
On 25 March 2022, Boeing issued the revised maintenance planning document for the Boeing 737 series that required repetitive inspections on the spoiler and aileron deployment and associated position sensors.
In popular culture
The accident will be featured in season 25 of the Canadian documentary series Mayday, titled "Power Struggle".
See also
List of accidents and incidents involving commercial aircraft
List of accidents and incidents involving the Boeing 737
List of aviation accidents and incidents in Indonesia
Similar accidents and incidents:
TAM Transportes Aéreos Regionais Flight 402 (thrust reverser failure and lack of crew training leading to crash on take-off, 99 killed), 1996
TAROM Flight 371 (auto-throttle failure and pilot incapacitation, 60 killed), 1995
Notes
References
External links
Preliminary Report - National Transportation Safety Committee
2021 disasters in Indonesia
2020s in Jakarta
Accidents and incidents involving the Boeing 737 Classic
Aviation accidents and incidents in 2021
Aviation accidents and incidents in Indonesia
Aviation accidents and incidents in the Pacific Ocean
Airliner accidents and incidents caused by mechanical failure
Airliner accidents and incidents caused by pilot error
January 2021 events in Indonesia
Java Sea
Marine salvage operations
Soekarno–Hatta International Airport
Thousand Islands Regency
2021 disasters in Oceania | Sriwijaya Air Flight 182 | [
"Materials_science"
] | 7,919 | [
"Airliner accidents and incidents caused by mechanical failure",
"Mechanical failure"
] |
66,330,928 | https://en.wikipedia.org/wiki/Batsheva%20Kerem | Batsheva Kerem (born 1955) is an Israeli geneticist who was on the research team that identified and cloned the CFTR gene, which when mutated, is responsible for causing cystic fibrosis (CF). She later established the Israel National Center for CF Genetic Research. She discovered the most prevalent cystic fibrosis-causing mutations among the Israeli population, allowing for the establishment of nationwide genetic screening programs to identify carriers of these mutations and enabling prenatal diagnoses. She researches how some CF mutations prevent CFTR protein production by causing nonsense-mediated decay and abnormal mRNA splicing, and how therapies might be able to counteract those problems. She also studies the role of genetic instability in cancer. She is currently a professor at the Hebrew University.
Early life and education
Batsheva Kerem was born in Tel-Aviv in 1955 and raised in Israel. She served as an IDF officer in the military. She received a B.Sc. with distinction in biology from the Hebrew University in 1979, followed by a Ph.D. from the direct doctoral program of Hebrew University's Department of Genetics in 1986. Her Ph.D work was supervised by Menashe Marcus and Howard Cedar. She did a brief post doctoral fellowship with Tamar Schaap in the Department of Genetics at Jerusalem's Hadassah Medical School, from 1986 to 1987. She then moved to Canada for further postdoctoral training at the Hospital for Sick Children in Toronto, Canada (commonly known as SickKids), where she worked in the laboratory of Lap-Chee Tsui from 1987 to 1990.
Career
Kerem has spent her career at the Hebrew University. She was hired as a senior lecturer in 1990, at which time she established the Israel National Center for CF Genetic Research. She was promoted to associate professor in 1998 and Full Professor in 2003. She established the National Genomic Knowledge Center at Hebrew University's Institute of Life Sciences and served as its chair from 2000-2014. She served as the Head of Authority for research students from 2007-2011. She was appointed President Advisor for Promotion of Women in Science in 2013. She is a member of the European Research Council (ERC) for advanced scientists and has served on the editorial board of the European Journal of Human Genetics and EMBO Reports. She was appointed President of the Genetic Society of Israel in 2007.
Research
Kerem helped identify the gene behind cystic fibrosis, the CFTR gene (short for cystic fibrosis transmembrane conductance regulator), which was found to be an ion channel. This work was carried out when she was a postdoctoral fellow in the lab of Lap-Chee Tsui at the Hospital for Sick Children (SickKids) in Toronto, Canada, and was a collaboration between Tsui's lab, including fellow postdoctoral researcher Johanna Rommens, and a team of researchers led by Francis Collins at the University of Michigan. The CFTR gene was discovered through genetic linkage analysis involving looking for genetic markers that were present in patients with cystic fibrosis but not present in their non-affected relatives. Due to the phenomenon of recombination, whereby parts of chromosomes swap homologous segments during germ cell development, each chromosome a child inherits is a mix of the both of that parent's copies of that chromosome. Markers would only be consistently co-inherited with the gene behind cystic fibrosis if they were close together on the chromosome, so Kerem and other researchers used markers to find the approximate location of the gene. They then used a combination of chromosome walking and chromosome hopping or jumping to locate the CF gene, which they named cystic fibrosis transmembrane conductance regulator (CFTR). Kerem helped identify the globally most common CFTR mutation, F508del, a deletion of the 508th amino acid (protein letter) in the CFTR protein, which is normally a phenylalanine (abbreviated F).
Part of her work at SickKids involved examining blood samples sent from around the world and, when looking at the CFTR gene in samples sent from Israeli patients, she found that they didn't carry any of the previously-identified mutations. She became intrigued so, when she moved back to Israel in September 1990, she collected blood from most Israeli CF patients and searched their CFTR genes for mutations. She discovered that about 60% of Israel's Ashkenazi Jewish CF patients had a nonsense mutation abbreviated as W1282X (signifying that the genetic instructions for 1282rd amino acid in the protein, which is normally a tryptophan (W), has been mutated to a stop signal (X)). This early stop signal, a premature termination codon (PTC), caused the production of truncated, dysfunctional CFTR protein. She published this finding in 1992 and in 1997, Israel's government introduced population carrier screening for it.
Much of Kerem's later contributions to cystic fibrosis research involves studying defects in the production of CFTR caused by premature termination and improper RNA splicing. In order to make a protein, a cell first makes RNA copies of the DNA gene for that protein. These RNA copies contain regulatory regions called introns which are removed in a process called RNA splicing in order to produce mature messenger RNAs (mRNAs) which are used by the cell's protein-making machinery (ribosomes and helpers) to make the corresponding protein in a process called translation. Certain CF-causing mutations, instead of affecting the CFTR protein's shape and functioning, affect how the messenger RNA (mRNA) copies of the genetic recipe for CFTR are processed, thus preventing CFTR protein from being made.
In addition to identifying and classifying the wide spectrum of CFTR mutations, Kerem studies how therapies might be able to counteract the problems present among the various classes. For example, Kerem researches how pharmaceutical compounds that promote read-through of these stop codons might be able to counteract problems caused by premature termination codon (PTC) mutations such as the W1282X she discovered was common among Ashkenazi Jewish patients. Additionally, she invented a discovery platform which serves as the basis of the biotechnology company SpliSense, which is working to develop antisense oligonucleotides (ASOs) to counteract mRNA splicing mutations by using small segments of DNA complementary to specific regions of the RNA in order to hide improper splice sites and promote proper splicing.
In the late 1990s she began studying chromosome structure and function. She has investigated genome instability and made significant contributions to knowledge of the involvement of frequent fragile sites in cancer.
Personal life
Batsheva Kerem is married to Dr. Eitan Kerem, head of the Division of Paediatrics at the Hadassah Medical Organization, who also researches cystic fibrosis. They have carried out collaborative research together, including the development of potential therapeutics. The reason Batsheva chose a postdoctoral fellowship in Tsui's lab at SickKids was in part because she and Eitan were looking for job opportunities where they would be able to work nearby one another. She carried out her groundbreaking CF research in Tsui's lab while a mother to two children. Batsheva has spoken out about gender inequality in science and, when she was one of the few women to receive an EMET Prize, she used the opportunity to advocate for better representation of women among prize recipients.
Honors
Julodan Prize for Contribution to Medicine (1993)
Teva Prize for Excellence in Human Genome Research (1993)
Joels Senior Lectureship for Excellence in Science (1996)
Abisch-Frenkel Prize for Excellence in Life Sciences (2004)
EMET Prize Laureate – Life Sciences: Genetics (2008)
Key publications
References
Molecular geneticists
1955 births
Israeli geneticists
Living people | Batsheva Kerem | [
"Biology"
] | 1,622 | [
"Molecular geneticists",
"Molecular genetics"
] |
66,333,418 | https://en.wikipedia.org/wiki/Satellite%20dispenser | A satellite dispenser is a space tug usually released from the upper stage (sometimes called kick stage) of a rocket and designed to fly small secondary payloads to their desired location before deploying them.
Project West Ford launched 480,000,000 needles in space in 1961 and 1963 using a dispenser.
The company Moog Inc. launched a satellite dispenser on a Falcon 9 rocket on 14 July 2014, placing 6 Orbcomm satellites in orbit.
SHERPA is a satellite dispenser first launched on 3 December 2018 on a rideshare mission called SSO-A: SmallSat Express. The two SHERPA dispensers placed 64 satellites, after separating from the Falcon 9 Block 5 rocket once it entered a polar Sun-synchronous orbit around 575 kilometers above Earth.
Canisterized Satellite Dispenser is a satellite dispenser created by Planetary Systems Corp, launched on 17 April 2019 with the Cygnus NG-11 mission.
ION CubeSat Carrier is a satellite dispenser launched on 3 September 2020 on a Vega rocket, mission Vega flight VV16, and carried 12 SuperDove satellites from Planet Labs.
The company Launcher is developing an orbital transfer vehicle named Orbiter which will be able to carry up to 90U of cubesats or other smallsats.
See also
KickSat
Space tug
Notes | Satellite dispenser | [
"Astronomy"
] | 286 | [
"Astronomy stubs",
"Spacecraft stubs"
] |
66,333,589 | https://en.wikipedia.org/wiki/Nicholas%20Timothy%20Belaiew | Nikolai Timofeevich Beliaev or Nicholas Timothy Belaiew (26 June 1878 – 5 November 1955) was a Russian metallurgist. He was famous for his studies on Damascus steel and the idea of crystallization in metals and the production of Widmanstatten structures. He also wrote on the history of steel making.
Beliaev was born in St. Petersburg to General T. M. Beliaev and Maria Nikolayevna Septjurina. He was educated at Mikhailovskaya Artilleriiskaya Academy and was trained under Dmitry Konstantinovich Chernov and Henry Le Chatelier. He became a professor of metallurgy in 1909. During World War I he was wounded and he was sent to England in 1915. He received a Bessemer Gold Medal in 1937 from the British Institute of Steel and Iron in London. A major contribution was on the studies of crystal structure in steels both man-made and of meteoric origin and examined their mechanical properties. He also took an interest in Icelandic research.
References
1878 births
1955 deaths
Metallurgists | Nicholas Timothy Belaiew | [
"Chemistry",
"Materials_science"
] | 220 | [
"Metallurgists",
"Metallurgy"
] |
66,336,004 | https://en.wikipedia.org/wiki/Redmi%209C | The Redmi 9C and Redmi 9C NFC are entry-level Android smartphones developed by Xiaomi's sub-brand Redmi. The Redmi 9C NFC differs by having an NFC module and only two rear camera lenses, unlike the Redmi 9C, which has a triple rear camera setup. The Redmi 9C was introduced on June 30, 2020, along with the Redmi 9A. The Redmi 9C NFC was introduced on August 27, 2020.
Also on August 27, the Redmi 9 was introduced in India, which is an Indian version of the Redmi 9C NFC and differs by having more memory and no NFC module.
History
On October 6, 2020, the POCO C3 was introduced, which is an Indian version of the Redmi 9C and differs slightly in the design of the back panel and lacks a fingerprint scanner.
On September 23, 2021, the Redmi 9 Activ was introduced in India, which differs from the Indian Redmi 9 with two new colors and more RAM.
On September 30, 2021, the POCO C31 was introduced in India, which generally differs from the POCO C3 in colors and has a fingerprint scanner.
Specifications
Design
The front is made of glass and the case is made of plastic.
At the bottom is a microUSB port, a speaker, and a microphone. At the top, there's a 3.5mm audio jack. On the left side of the smartphone, there's a slot for 2 SIM cards and a microSD memory card up to 512 GB. On the right side, there are volume control buttons and a power button. The fingerprint scanner is located at the center on the back panel.
The phone is available with multiple colors, depending on the model:
The Redmi 9C and Redmi 9C NFC were sold in 3 colors: Midnight Gray, Sunrise Orange, and Twilight Blue.
In India, the Redmi 9 was sold in 3 colors: Midnight Gray, Sunshine Yellow, and Twilight Blue and Carbon Black, Coral Green, and Metallic Purple for the Redmi 9 Activ.
The POCO C3 was sold in 3 colors: Arctic Blue, Lime Green, and Matte Black.
The POCO C31 was sold in 2 colors: Royal Blue and Shadow Gray.
Processor and GPU
The smartphones feature a MediaTek Helio G35 SoC with PowerVR GE8320 GPU.
Battery
The battery has a capacity of 5000 mAh.
Camera
The Redmi 9C, POCO C3, and POCO C31 feature a triple rear camera setup consisting of a 13MP, wide-angle lens with phase-detection autofocus and a 2MP, macro lens and depth sensor. The Redmi 9C NFC, Indian Redmi 9, and Redmi 9 Activ lack the macro lens.
All smartphones in this series have a 5MP, wide-angle front-facing camera.
Both the rear and front cameras on all models can record video at 1080p resolution at 30 fps.
Display
The devices have a 6.53" IPS LCD screen with an HD+ (1600 × 720 pixels) resolution, a 20:9 aspect ratio, 269 ppi pixel density, and a teardrop notch for the front camera.
Storage
The Redmi 9C and Redmi 9C NFC were available in 2GB/32GB and 3GB/64GB storage configurations.
The POCO C3 and C31 were available in 3GB/32GB and 4GB/64GB storage configurations.
The Redmi 9 was available in 4GB/64GB and 4GB/128GB storage configurations.
The Redmi 9 Activ was available in 4GB/64GB and 6GB/128GB storage configurations.
Software
Both versions of the Redmi 9C, the Indian Redmi 9, and the Redmi 9 Activ were released with MIUI 12. The POCO C3 and C31 came with MIUI 12 for POCO. Both interfaces are based on Android 10. Both versions of the Redmi 9C, the Indian Redmi 9, and the Redmi 9 Activ have been updated to MIUI 12.5 based on Android 11, while the POCO C31 has been updated to MIUI 12.5 for POCO based on Android 11.
References
External links
Redmi 9C official website
Redmi 9C NFC official website in Ukrainian
Official Indian Redmi 9 website
Redmi 9 Activ official website
POCO C3 official website
POCO C31 official website
9C
Mobile phones with multiple rear cameras
Mobile phones introduced in 2020
Phablets
Discontinued smartphones | Redmi 9C | [
"Technology"
] | 946 | [
"Crossover devices",
"Phablets"
] |
78,005,937 | https://en.wikipedia.org/wiki/Kiyoshi%20Yabuuchi | Kiyoshi Yabuuchi (Yabuuchi Kiyoshi 薮内 清; 12 February 1906 (Meiji 39) – 2 June 2000 (Heisei 12)), often written in Kunrei-shiki romanization as Kiyosi Yabuuti, was a Japanese astronomer and historian of science. He gained an international reputation as a leading pioneer in the field of pre-1840 Chinese mathematics and Chinese astronomy.
Biography
Born in Kobe, Kiyoshi Yabuuchi studied science at Koyo Gakuin High School and Osaka High School (now part of Osaka University). At Kyoto University he studied the history of Chinese astronomy under Shinzo Shinjo and graduated from the Department of Astrophysics and the Graduate School of Science and Faculty of Science in 1929. Yabuuchi became in 1929 an assistant at Kyoto University and became in 1935 a consultant at the Kyoto Institute of Oriental Culture (now part of the Kyoto University Research Centre for the Cultural Sciences), later becoming a researcher there. In 1948 he was appointed a researcher at Kyoto University, and in 1949 he became a professor at the Institute for Research in Humanities at Kyoto University (now part of the Kyoto University Research Centre for the Cultural Sciences). There he developed research on the history of science in China to a world-class level through collaborative research. In 1967, he became director of the institute. During that time, he served, beginning in 1955, as vice president of the Astronomical Society of Japan. In 1959 he was a visiting professor in Teheran. In 1969, he retired from Kyoto University as professor emeritus and lived in Kyoto until he died at age 94. From 1969 to 1979, he was a professor at Ryukoku University. In retirement, Yabuuchi worked diligently to share his research with Japanese readers and scholars by means of public lectures, appearances on local television programs, and newspaper articles. He summarized all his public lectures into a collection of published works.
Yabuuchi's best known work on the history of Chinese mathematics, 支那数学史 (History of Chinese mathematics, published in 1944), was translated into French with the title Une histoire des mathématiques chinoises (2000, Editions Belin) by Kaoru Baba and Catherine Jami. In his intensive research into the history of Chinese astronomy, he particularly examined the influences of Islamic astronomy and the relationship between Indian astronomy and Chinese astronomy. Michio Yano, a former doctoral student of Yabuuchi, emphasized strong similarities between Yabuuchi's working methods and the methodology of the mathematician and astronomer Otto Neugebauer:
Awards and honors
Yabuuchi received in 1969 the Asahi Prize and in 1972 the George Sarton Medal. An asteroid discovered in April 1953 by Karl Wilhelm Reinmuth was named 2652 Yabuuti, based upon a suggestion by Kiichirō Furukawa, a former student of Yabuuchi. In 1976 Yabuuchi was awarded the Order of the Sacred Treasure, Second Class. In 1983 he was elected a member of the Japan Academy.
Selected publications
『支那の天文学』（恒星社厚生閣 1943）(History of Chinese Astronomy, published by Koseisha)
『中国の天文学』（恒星社厚生閣 1949）(Chinese Astronomy, published by Koseisha)
『支那数学史概説』（山口書店 1944）(Outline of the History of Chinese Mathematics; published by Yamaguchi Shoten)
『支那数学史』（山口書店 1944) (History of Chinese Mathematics; published by Yamaguchi Shoten)
Indian and Arabian astronomy in China. In: Silver Jubilee Volume of the Zinbun-Kagaku-Kenkyusyo Kyoto University. Kyoto 1954, p. 585.
Kaoru Baba (translator), Catherine Jami (translator): Une histoire des mathématiques chinoises. Éditions Belin, Pour la Science, Paris 2000, ISBN 2-7011-2404-2.
Sources
The 1972 George Sarton Medal Awarded to Kiyoshi Yabuuchi. In: Isis 64, 1973, p. 103.
Catherine Jami: In Memory of Prof. Kiyosi Yabuuti Presentation. In: East Asian Science, Technology, and Medicine. 18, 2001, , pp. 10–12.
Yabuuchi Kiyoshi as a Historian of Exact Sciences. In: East Asian Science, Technology, and Medicine. 18, 2001, , pp. 13–19.
Kiyoshi Yabuuchi. In: Archives internationales d’histoire des sciences. 51, 2001, , pp. 155–157.
References
1906 births
2000 deaths
20th-century Japanese historians
Historians of science
Historians of astronomy
Historians of mathematics
Kyoto University alumni
Academic staff of Kyoto University
Members of the Japan Academy | Kiyoshi Yabuuchi | [
"Astronomy"
] | 979 | [
"People associated with astronomy",
"Historians of astronomy",
"History of astronomy"
] |
78,006,261 | https://en.wikipedia.org/wiki/Semorinemab | Semorinemab (, ; developmental code names MTAU-9937A, RG-6100, RO-7105705) is a monoclonal antibody against tau which was under development for the treatment of Alzheimer's disease but was discontinued. It binds to the N-terminus of all six isoforms of tau. The drug was ineffective in the treatment of Alzheimer's disease in two phase 2 clinical trials. Clinical development of semorinemab for Alzheimer's disease was discontinued in February 2024.
References
External links
Semorinemab - AlzForum
Abandoned drugs
Experimental drugs for Alzheimer's disease
Experimental monoclonal antibodies | Semorinemab | [
"Chemistry"
] | 135 | [
"Drug safety",
"Abandoned drugs"
] |
78,006,491 | https://en.wikipedia.org/wiki/Existential%20Closedness%20conjecture | In mathematics, specifically in the fields of model theory and complex geometry, the Existential Closedness conjecture is a statement predicting when systems of equations involving addition, multiplication, and certain transcendental functions have solutions in the complex numbers. It can be seen as a conjectural generalisation of the Fundamental Theorem of Algebra and Hilbert's Nullstellensatz which are about solvability of (systems of) polynomial equations in the complex numbers.
The conjecture was first proposed by Boris Zilber in his work on the model theory of complex exponentiation. Zilber's conjecture is known as Exponential Closedness or Exponential Algebraic Closedness and covers the case of Existential Closedness when the transcendental function involved is the complex exponential function. It was later generalised to exponential functions of semiabelian varieties, and analogous conjectures were proposed for modular functions and Shimura varieties.
Statement
Informally, given a complex transcendental function , the Existential Closedness conjecture for states that systems of equations involving field operations and always have solutions in unless the existence of a solution would obviously contradict the (hypothetical) algebraic and transcendental properties of . Two precise cases are considered below.
Exponential Closedness
In the case of the exponential function , the algebraic property referred to above is given by the identity . Its transcendental properties are assumed to be captured by Schanuel's conjecture. The latter is a long-standing open problem in transcendental number theory and implies in particular that and are algebraically independent over the rationals.
Some systems of equations cannot have solutions because of these properties. For instance, the system has no solutions, and similarly for any non-zero polynomial with rational coefficients the system has no solution if we assume and are algebraically independent. The latter is an example of an overdetermined system, where we have more equations than variables. Exponential Closedness states that a system of equations, which is not overdetermined and which cannot be reduced to an overdetermined system by using the above-mentioned algebraic property of , always has solutions in the complex numbers. Formally, every free and rotund system of exponential equations has a solution. Freeness and rotundity are technical conditions capturing the notion of a non-overdetermined system.
Modular Existential Closedness
In the modular setting the transcendental function under consideration is the -function. Its algebraic properties are governed by the transformation rules under the action of – the group of rational matrices with positive determinant – on the upper half-plane. The transcendental properties of are captured by the Modular Schanuel Conjecture.
Modular Existential Closedness states that every free and broad system of equations involving field operations and the -function has a complex solution, where freeness and broadness play the role of freeness and rotundity mentioned above.
Relation to Schanuel's conjecture
Existential Closedness can be seen as a dual statement to Schanuel's conjecture or its analogue in the appropriate setting. Schanuel implies that certain systems of equations cannot have solutions (or solutions which are independent in some sense, e.g. linearly independent) as the above example of exponential equations demonstrates. Then Existential Closedness can be interpreted roughly as stating that solutions exists unless their existence would contradict Schanuel's conjecture. This is the approach used by Zilber. His axiomatisation of pseudo-exponentiation prominently features Schanuel and a strong version of Existential Closedness which is indeed dual to Schanuel. This strong version predicts existence of generic solutions and follows from the combination of the Existential Closedness, Schanuel, and Zilber-Pink conjectures. However, Existential Closedness is a natural conjecture in its own right and makes sense without necessarily assuming Schanuel's conjecture (or any other conjecture). In fact, Schanuel's conjecture is considered out of reach while Existential Closedness seems to be much more tractable as evidenced by recent developments, some of which are discussed below.
Partial results and special cases
The Existential Closedness conjecture is open in full generality both in the exponential and modular settings, but many special cases and weak versions have been proven. For instance, the conjecture (in both settings) has been proven assuming dominant projection: any system of polynomial equations in the variables and (or ), which does not imply any algebraic relation between , has complex solutions. Another important special case is the solvability of systems of raising to powers type. Differential/functional analogues of the Existential Closedness conjecture have also been proven.
See also
Schanuel's conjecture
Zilber-Pink conjecture
References
Conjectures
Complex geometry
Model theory | Existential Closedness conjecture | [
"Mathematics"
] | 962 | [
"Unsolved problems in mathematics",
"Mathematical logic",
"Conjectures",
"Model theory",
"Mathematical problems"
] |
78,006,672 | https://en.wikipedia.org/wiki/Dosage%20%28pharmacology%29 | In pharmacology and medicine, dosage refers to the prescribed regimen for administering a medication or substance, encompassing the amount, frequency, and duration of use. It is distinct from dose, which denotes a single, specific quantity of a drug or substance given at one time. Dosage typically includes information on the number of doses, intervals between administrations, and the overall treatment period. For example, a dosage might be described as "200 mg twice daily for two weeks," where 200 mg represents the individual dose, twice daily indicates the frequency, and two weeks specifies the duration of treatment.
References
Medication pharmacology | Dosage (pharmacology) | [
"Chemistry"
] | 129 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
78,006,722 | https://en.wikipedia.org/wiki/DA-Phen | DA-Phen, also known as dopamine–phenylalanine conjugate, is a synthetic dopamine prodrug which is under preclinical evaluation. Dopamine itself is hydrophilic and is unable to cross the blood–brain barrier, thus showing peripheral selectivity. DA-Phen was developed as a dopamine prodrug that would allow for entry into the central nervous system via passive diffusion and/or active transport.
DA-Phen is a conjugate of dopamine and the amino acid phenylalanine (Phe or Phen). It is slowly cleaved by brain enzymes (t½ = 460minutes) to yield free dopamine but is also rapidly hydrolyzed in human blood plasma (t½ = 28minutes). The drug was intended as a prodrug but may also directly interact with the dopamine D1-like and/or D2-like receptors. DA-Phen has shown centrally mediated effects in animals, including increased cognitive flexibility, improved spatial learning and memory, antidepressant- and anxiolytic-like effects, and decreased ethanol intake.
Other analogues, such as DA-Trp and DA-Leu, have also been developed and studied.
See also
Neurotransmitter prodrug
Lisdexamfetamine (dextroamphetamine–lysine conjugate)
DopAmide
Docarpamine
References
Amino acids
Catecholamines
Dopamine agonists
Experimental drugs
Monoamine precursors
Phenethylamines
Prodrugs | DA-Phen | [
"Chemistry"
] | 339 | [
"Amino acids",
"Biomolecules by chemical classification",
"Chemicals in medicine",
"Prodrugs"
] |
78,007,021 | https://en.wikipedia.org/wiki/O%2CO%E2%80%B2-Dipivaloyldopamine | O,-Dipivaloyldopamine, or simply dipivaloyldopamine, also known as 3,4-dipivaloyloxyphenethylamine, is a synthetic derivative of dopamine in which both of the hydroxyl groups have been acetylated. It was developed as a lipophilic prodrug of dopamine that would allow for entry of dopamine into the central nervous system.
Dopamine itself is too hydrophilic to cross the blood–brain barrier and hence is peripherally selective. This, in part, prevents dopamine itself from being employed medically for central nervous system uses. Whereas the experimental log P of dopamine is -0.98, the predicted log P (XLogP3) of O,O'-dipivaloyldopamine is 3.1. The optimal log P for brain permeation and central activity is at least 1.5.
O,-Dipivaloyldopamine produced hypothermia in animals, thought to be a centrally mediated dopaminergic effect, but failed to reverse behavioral depression induced by the monoamine depleting agent reserpine. On the other hand, another analogue, N,N-dimethyl-O,-dipivaloyldopamine (XLogP3 = 4.1), produced both hypothermia and reversed reserpine-induced behavioral depression.
See also
Neurotransmitter prodrug
O,-Diacetyldopamine
Docarpamine
Dipivefrin (O,-dipivalylepinephrine)
O-Pivalylbufotenine
References
Abandoned drugs
Catecholamines
Dopamine
Dopamine agonists
Monoamine precursors
Phenethylamines
Pivalate esters
Prodrugs | O,O′-Dipivaloyldopamine | [
"Chemistry"
] | 390 | [
"Chemicals in medicine",
"Drug safety",
"Prodrugs",
"Abandoned drugs"
] |
78,007,448 | https://en.wikipedia.org/wiki/Il%20Primo%20Dubai | Il Primo Tower is a supertall residential skyscraper in Dubai, United Arab Emirates. Built between 2017 and 2023, the tower stands at tall with 79 floors, currently sharing the fifth spot on the list of the tallest buildings in Dubai with the Gevora Hotel.
History
Architecture
The tower is located in the Downtown Opera District in the proximity of Burj Khalifa, the Dubai Mall and the Dubai Opera. The building topped out in 2021 by WSP Middle East, together with Emaar Development PJSC, features a 79-storey tower along with a podium and six levels of underground parking. The residential units are designed with vistas of famous city buildings and include various features and luxuries like marble flooring, soft lighting, and contemporary artwork.
The tower offers luxurious living conditions, especially throughout the upper floor penthouses designed by B8 Architecture Dubai studio. On the ground floor of the first penthouse, there is a tall living room with a sculptural spiral staircase at its center, which represents the main visual attraction. Next to it, there is a wine cellar in the bar-lounge area. The spiral staircase gallery connects the two main areas on the first floor.
See also
List of tallest buildings in Dubai
List of tallest buildings in the United Arab Emirates
List of tallest residential buildings
References
External links
Il Primo Tower at CTBUH
Il Primo Tower at SkyscraperPage
Il Primo Tower at Structurae
Residential skyscrapers in Dubai
Residential buildings completed in 2023
Buildings and structures completed in 2023
2023 establishments in the United Arab Emirates
Residential skyscrapers
High-tech architecture
Postmodern architecture | Il Primo Dubai | [
"Engineering"
] | 328 | [
"Postmodern architecture",
"Architecture"
] |
78,007,456 | https://en.wikipedia.org/wiki/3%2C4-Dihydroxymethamphetamine | 3,4-Dihydroxymethamphetamine (HHMA, 3,4-DHMA), or 3,4-dihydroxy-N-methylamphetamine, also known as α-methylepinine or α,N-dimethyldopamine, is the major metabolite of 3,4-methylenedioxy-N-methylamphetamine (MDMA). It is formed from MDMA by O-demethylation via cytochrome P450 enzymes including CYP2D6 as well as CYP1A2 and CYP3A4. Like MDMA, HHMA is a monoamine releasing agent.
Along with 3,4-dihydroxyamphetamine (HHA; α-methyldopamine), HHMA may be involved in the serotonergic neurotoxicity of MDMA. However, findings in this regard are conflicting, and the neurotoxicity of MDMA and related agents may instead be based on their mechanism of action without involvement of metabolites.
See also
3,4-Dihydroxyamphetamine (HHA; α-methyldopamine)
4-Hydroxy-3-methoxyamphetamine (HMA)
4-Hydroxy-3-methoxymethamphetamine (HMMA)
2,4,5-Trihydroxyamphetamine (THA)
2,4,5-Trihydroxymethamphetamine (THMA)
References
Catecholamines
Human drug metabolites
Human pathological metabolites
Methamphetamines
Monoaminergic neurotoxins
Norepinephrine-dopamine releasing agents | 3,4-Dihydroxymethamphetamine | [
"Chemistry"
] | 367 | [
"Chemicals in medicine",
"Human drug metabolites"
] |
78,008,700 | https://en.wikipedia.org/wiki/Cyclobutanedione | Cyclobutanedione may refer to:
1,2-Cyclobutanedione
1,3-Cyclobutanedione | Cyclobutanedione | [
"Chemistry"
] | 35 | [
"Isomerism",
"Set index articles on molecular formulas"
] |
78,008,724 | https://en.wikipedia.org/wiki/C18H18N4O2 | {{DISPLAYTITLE:C18H18N4O2}}
The molecular formula C18H18N4O2 may refer to:
Armesocarb
Mesocarb | C18H18N4O2 | [
"Chemistry"
] | 41 | [
"Isomerism",
"Set index articles on molecular formulas"
] |
78,008,871 | https://en.wikipedia.org/wiki/Trans-2-Hexenal | trans-2-Hexenal is an organic unsaturated aldehyde with a six-carbon chain. This clear, pale yellow liquid has a green, leafy, herbal fruit smell. It occurs naturally in a wide variety of plants, fruits, vegetables, and spices, and appears to be an important mediating and signalling chemical in plant-fungus and plant-insect interactions, such as the symbiosis between acacia ants and Acacias.
Occurrence
This aldehyde is a commonly produced volatile organic compound (VOC) among the flowering plants. It is among the VOCs known as green leaf volatiles, as they are released following damage to the leaf, whether by crushing, herbivory, or bacterial or fungal infection. It is also found in other parts of the plant. For example, it was found to constitute 34% of the total VOCs from fresh strawberry fruits and 28% of VOCs from fresh tomato fruits.
trans-2-hexenal appears to be an airborne signalling chemical that can upregulate plant defenses, from leaf to leaf on the same plant as well as between neighboring plants. It has been shown to inhibit the growth of fungal pathogens.
It is also implicated in the mutualistic relationship between Acacia and related trees and their ant partners. The bullhorn acacia tree, Vachellia cornigera, grows inflated hollow spines at the base of its leaves that serve as nesting places for its symbiotic partner, the acacia ant, Pseudomyrmex ferruginea. The tree produces sugary nectar and fat- and protein-rich nutrient packets at the tips of its leaflets to serve as food for the ants. In return, the ants react aggressively towards any pest or herbivore which damages the Acacia leaves. It is the release of trans-2-hexenal from the damaged leaf that the ants sense and react to.
Uses
This aldehyde is approved for use as a food additive and is used, highly diluted, in perfumery. It is said to lend a green apple, leafy, herbal, spicy banana note to a fragrance.
It may also find use as an antifungal agent, including as a post-harvest fruit preservative.
See also
Myrmecophyte, a plant that lives in a mutualistic association with ants
Synomone, a signalling chemical which benefits both parties in a symbiotic relationship
Plant defense against herbivory
Plant communication
cis-3-Hexenal, a similar aldehyde which also mediates plant-insect interactions
References
Insect pheromones
Insect ecology
Plant communication
Fungicides
Alkenals | Trans-2-Hexenal | [
"Chemistry",
"Biology"
] | 545 | [
"Insect pheromones",
"Fungicides",
"Chemical ecology",
"Plants",
"Plant communication",
"Biocides"
] |
78,009,095 | https://en.wikipedia.org/wiki/HIP%2081208 | HIP 81208 (HD 149274) is a young triple or quadruple hierarchical star system in the constellation of Scorpius. It consists of a B-type main sequence star (component A), a brown dwarf (B), and a red dwarf (C), the latter two distantly orbiting the primary star. The stars are part of the Scorpius–Centaurus association. In 2023, HIP 81208 C was found to be orbited by a substellar object, which is at the border between being a massive exoplanet and a low-mass brown dwarf. This made HIP 81208 the first stellar binary with substellar objects orbiting both stellar components ever discovered by direct imaging. With an apparent magnitude of 6.64, it is barely visible by the naked eye under dark skies.
Stellar properties
The dominant component of the system, HIP 81208 A is a bright blue-white star with a spectral type of B9V, which is about 2.2 times larger, 2.6 times more massive, and 60 times more luminous than the Sun. It is very young at only 17 million years old, less than 0.4% the age of the Solar System (4.6 billion years).
In 2023, two smaller objects, respectively designated HIP 81208 B and C, were detected near the star using the SPHERE instrument at the Very Large Telescope in Antofagasta Region, Chile. They both have similar proper motions to HIP 81208 A, strongly supporting that the objects are physically bound to it.
HIP 81208 B is a high-mass (67 ) brown dwarf with an effective temperature of , mostly due to residual heat from formation. It orbits the primary star at a distance of once every 247 years (albeit with a large margin of error), close to the orbital period of Pluto (247.94 years). HIP 81208 C orbits the star much farther at with a 2,242-year period, though its orbital parameters are also poorly constrained. It has a temperature of , only slightly hotter than the brown dwarf. Curiously, the orbits of the two companions are almost orthogonal to one another, and are probably in a Kozai resonance with the host star.
Possible fourth star
The 15th-magnitude star Gaia DR3 6020420074469092608 (2MASS J16360769-3543514), located at a separation of , shares a similar parallax and proper motion with HIP 81208, and is potentially located within the Hill sphere of the system. This hints at the possibility of a fourth stellar component even farther from the primary star than the confirmed two.
Planetary system
In 2023, a previously unresolved object was identified in orbit of HIP 81208 C. The object, with a mass of 14.8 , is right at the boundary between exoplanets and brown dwarfs, as it is close to the threshold for deuterium fusion (~13 ). This made the HIP 81208 system the first binary between two stars (A, C) discovered by imaging where both stars are orbited by substellar companions (B, Cb). It orbits the red dwarf host somewhere around distant with a period of roughly 285 years.
HIP 81208 Cb is also unique in that it is unusually close to its host star for being a giant planet or brown dwarf companion to a late M-type star. Other objects of a similar nature, at least those that have been directly imaged, usually have a mass similar to that of the host star that a binary-like formation is likely, but HIP 81208 Cb is light enough that such a formation mode can be ruled out. The true formation of the object, however, remains inconclusive.
Footnotes
References
B-type main-sequence stars
M-type main-sequence stars
Brown dwarfs
Triple star systems
Scorpius
149274
CD-35 11037
J16351384-3543287
081208 | HIP 81208 | [
"Astronomy"
] | 831 | [
"Scorpius",
"Constellations"
] |
78,010,827 | https://en.wikipedia.org/wiki/Stephan%20Roche | Stephan S. Roche is a Catalan theoretician studying quantum transport theory in condensed matter, spin transport physics and devices simulation. Roche has been a Catalan Institution for Research and Advanced Studies research professor since 2009 and the head of the theoretical & computational nanoscience Group at the Catalan Institute of Nanoscience and Nanotechnology.
Roche works in the fields of theoretical and computational nanoscience, with expertise in quantum transport physics in Dirac materials (graphene & topological insulators) and 2D materials-based van der Waals heterostructures. He made contributions of charge, thermal and spin transport phenomena in complex and disordered condensed matter. He also works on the development of linear scaling quantum transport approaches, methods which are now connected with Artificial Intelligence methods.
Research and career
S. Roche has co-authored around 270 journal papers.
He has been the Editor-in-Chief of J. Phys. Materials (IOP) since 2018 and the main organiser of the conference series GRAPHENE 20XX (www.grapheneconf.com) and, since 2011, QUANTUM MATTER 20XX (www.quantumconf.eu)
Awards and honours
Friedrich Wilhelm Bessel Award (Alexander Von-Humboldt Foundation, Germany) – 2009.
Selected publications
References
Nanotechnologists
Spanish physicists
Condensed matter physicists
Year of birth missing (living people)
Living people | Stephan Roche | [
"Physics",
"Materials_science"
] | 278 | [
"Nanotechnology",
"Condensed matter physicists",
"Condensed matter physics",
"Nanotechnologists"
] |
78,011,176 | https://en.wikipedia.org/wiki/MCG%20%2B08-11-011 | MCG +08-11-011 (MCG +8-11-11) known as UGC 3374, is a galaxy located in the constellation of Auriga. It is located 401 million light years from Earth and is classified as a Seyfert galaxy.
Characteristics
MCG +8-11-11 is classified a type 1 Seyfert galaxy. It is face-on spiral galaxy located at a projected distance of 123 megaparsecs. It has a soft X-ray luminosity originating from its nuclear core varying between 0.5 to 1 1044 erg s−1. It is also one of the brightest active galactic nuclei (AGN) observed in X-ray bands but radio-quiet. Through detected by most X-ray satellites, the galaxy wasn't one of the targets noticed by Chandra X-ray Observatory. It has an X-ray spectrum fitted by an estimated power law of Γ = 1.8 with an undetermined iron line likely originating from distant matter. The galaxy has soft gamma-ray emission at 3.9 σ level, higher than 90 keV.
Additionally, MCG +8-11-11 contains X-ray fluxes. Based on observations by the INTErnational Gamma-ray Astrophysics Observation (INTEGRAL), they have measurements of F20-100 keV = 8.46 x 10−11 erg cm−2 s−1 and F2-10 keV = 5.62 x 10−11 erg cm−2 s−1 respectively. Based from a spectral analysis conducted by NuSTAR, the galaxy has a bolometric luminosity estimated as Lbol = 14.2 x 1044 erg s−1. Furthermore, the black hole in MCG +8-11-11 has a mass of MBH = 7.19 ± 0.02 MΘ and an Eddington ratio of 7.54 x 10−1. The thermal emission from its accretion disk is hot with a temperature of kT = 0.088+0.018-0.007 keV.
Observations
MCG +8-11-11 has been observed in many occasions. In July 1995, its powerful gamma-ray flux was detected during a High Energy Astronomical Telescope balloon flight, suggesting its hard X-ray spectral feature was caused by a double-Compton backscattering exerted on its external cloud. A Suzaku observation conducted in 2010 finds out the galaxy exhibits spectral signatures from its accretion disk.
In November 2014, data from the observation by the 118 ks Chandra High Energy Transmission Gratings found MCG +8-11-11 shows lack of warm absorption and its Compton reflection signatures are described by out of direction material from the naked eye, based on an inclination angle of θ = 41+18−30 obtained by a MYTorus model. Between 2019 and 2020, it was determined that MCG +8-11-11 has a host-corrected AGN luminosity of 5100 Ά of (4.21 ± 0.65) x 1043 erg s−1 and a large disk-size according to a photometric reverberation mapping conducted by the Wise Observatory.
Radio source
MCG +8-11-11 hosts a triple radio source in its center with a projected size of 400 parsecs and an S-shaped morphology. However the central compartment of the source has a small diameter of 30 parsecs and is possibly confirmed as the active galaxy's core. The source is also found embedded in diffused emission with a major-axis position angle similar to its bar but offset by 50 degrees.
References
External links
UGC 3374 on SIMBAD
Seyfert galaxies
Auriga
018078
+08-11-011
03374
Active galaxies
05511+4625 | MCG +08-11-011 | [
"Astronomy"
] | 783 | [
"Auriga",
"Constellations"
] |
78,012,334 | https://en.wikipedia.org/wiki/Disputes%20on%20Wikipedia | Disputes on Wikipedia arise from Wikipedians, who are volunteer editors, disagreeing over article content, internal Wikipedia affairs, or alleged misconduct. Disputes often manifest as repeated competing changes to an article, known as "edit wars", where instead of making small changes, edits are "reverted" wholesale. Disputes may escalate into dispute resolution efforts and enforcement.
Disputes are encouraged to be discussed on talk pages, but can go straight to editing bans, and some editors just "walk away" from conflict, especially if they do not know how to defend their edits within Wikipedia's complex systems.
An early but persistent source of conflict is "proprietary editing", where an editor, who may have started an article, will not allow other editors to make changes to their content or language. Many current conflicts play out in articles about contentious topics, often with two entrenched opposing sides, that reflect debates and conflicts in society, based on ethnic, political, religious, and scientific differences.
Dispute resolution efforts have shifted over the years. For content disputes in English Wikipedia, as of 2024, editors most often resort to Requests for Comment, along with specialized discussion structures, such as Articles for Deletion. For alleged user misconduct, some Wikipedias rely on Arbitration Committees as the final word.
Disputes, editor behavior, and collaboration on Wikipedia have long been the subject of academic research, especially in the English Wikipedia. A 2023 review identified 217 articles about contributor goals, interactions, and collaboration processes, which identified 34 studies of "the causes and impact of conflict, the mechanisms for resolving conflict, and the measurement and prediction of conflict or controversial articles." The review examined numerous studies of editor coordination, especially on Talk pages, as well as algorithmic governance using bots to enforce Wikipedia policies. The review found that research attention peaked in 2012, and overall Wikipedia editing peaked in 2007.
Identification of disputes
As an open collaboration writing project, from the outset Wikipedia expected disagreements among contributors. The point at which disagreements turn into disputes, and conflicts, is not uniformly defined by Wikipedia communities and the scholars who study them.
Conflicts over content within articles often arise among editors, which may result in edit wars. An edit war is a persistent exchange of edits representing conflicting views on a contested article, or as defined by the website's policy: "when editors who disagree about the content of a page repeatedly override each other's edits." Edit wars are prohibited on Wikipedia and editors are encouraged to seek consensus through discussion, however administrative intervention may be applied if discussion is unfruitful in resolving the conflict. Generally, edit wars are provoked by the presence of highly controversial content, such as abortion or the Israeli–Palestinian conflict, but can also occur due to other disputed matters, such as the nationality of artist Francis Bacon. According to a 2020 study, the longest edit war sequence, with 105 reverts by 20 users, was a 2008 tug-of-war over the biography of Turkey's first president, Mustafa Kemal Atatürk.
Researchers also designed an analytical platform, titled Contropedia, to observe and measure protracted editing controversies, such as global warming.
Edit wars may be defined and detected in terms of reverts and mutual re-reverts. In 2004, the community instituted the three revert rule, which was examined in subsequent scholarship. The rule reportedly cut reverts in half. To identify editing disputes, scholars also tried using the number of article revisions, deletion rates between editors, or a tag placed on controversial articles. For example, up to mid-2020, there were in-depth Talk page arguments over 7,425 instances of a dispute tag. In 2012, Yasseri et al. identified disputes through a pattern recognition algorithm and tested it against human evaluations of article. By avoiding language-based criteria, they stated that their method "makes possible both inter-cultural comparisons and cross-language checks and validation". Accordingly, in a 2014 chapter, Yasseri led a different team to identify the most controversial articles in 10 Wikipedias, including Arabic, Hebrew, and Hungarian.
Later research has used other methods, even absent reverts and deletion patterns. A 2021 study claimed 80% accuracy in identifying "conflict-prone discussions" by their structural features, such as back and forth commenting by two editors (ABA pattern), before any contributions by a third person. Other features include phrases and pronoun usage that mark the level of politeness or collaboration. De Kock and Vlachos classified disputes with a natural language processing (NLP) model that improved on feature-based models.
Many disputes center on the deletion of written content, which can be seen as a kind of gatekeeping. In a comparative study of such network gatekeeping on French and Spanish decolonization cases, it was found that more active editors experience fewer deletions and appear to function within rival camps.
Impact of disputes
Disputes are widely seen as a drain on the Wikipedia community, without adding to useful knowledge, and as creating a competitive and conflict-based culture associated with conventional masculine gender roles. Research has focused on the impoliteness of disputes, which can harm personal identities, "violate boundaries", and diminish voluntarism. Entrenched editor conflicts are said to detract from the quality and purported neutrality of Wikipedia articles.
Occasionally, a behind-the-scenes dispute will garner negative media attention as a Wikipedia controversy. For example, after the 2019 ban of a user by the Wikimedia Foundation, media stories covered the internal debate and the resignation of 21 administrators from English Wikipedia. Nonetheless, adversarial editing has been defended by Wikipedia leadership as important for collaboration and scholars have argued that well-managed friction among editors can benefit the encyclopedia. Controversial topics may also attract editors, as found by a 2017 lab experiment with people exposed to German Wikipedia.
Features of disputes
With civility as a core principle of Wikipedia, user disputes often feature impoliteness. According to a study of disputes on 120 Talk pages, by and large "Wikipedians do not prolong the conflicts." The most common incivility is scorn, ridicule, or condescension, followed by "pointed criticism". Impolite comments got no traction, no response, two-fifths of the time. Regardless of the topic area, overt responses were divided: 37 percent of responses to rude conduct were defensive, such as explaining oneself or asking for information about the critic's concern. However, 53.5 percent of the time, people responded offensively. According to a similar study, personal attacks were reciprocated 26% immediately.
Editors use a range of rebuttal tactics, ranging from insults to derailing to counterargument and refutation. Higher quality rebuttals "correlate to more constructive outcomes". Coordination tactics include asking questions, providing information, supplying context, offering a compromise, conceding or admitting lack of knowledge. Deferential wording reduces conflict, such as the phrase "by the way" or hedging to signal an openness to compromise.
During editing disputes, Wikipedians have been found to adopt five conversational roles: architect (of the discussion structure), content expert, moderator, policy wonk, and wordsmith. The edit-focused roles, of expert and wordsmith, tended to be more successful than the conceptual, organizational roles, such as policy wonk. Indeed, when editors bring up Wikipedia policies during a general content dispute, "wiki-lawyering", they tend to escalate the editorial conflict. Still, researchers found that citing Wikipedia policy, such as Notability, does help settle disputes over the deletion of articles.
Editing disputes may go through stages or a life cycle, as David Moats showed for the use of sources in the early days of writing about the Fukushima nuclear accident.
Deletion disputes
Disagreements over the deletion of articles, and other types of encyclopedic content (e.g., categories and lists), are managed through discussion structures. Notably, Wikipedia (English) has had more than 400,000 Articles for Deletion (AfD) discussions since 2004, though the rate of AfD submissions has declined after Wikipedia article creation was restricted in 2017.
As of 2018, roughly 64 percent of debates ended in deletion and 24 percent in keeping the article, a ratio that is much lower than the early years of Wikipedia. Nearly all discussions are "closed" by a Wikipedian administrator. In 2019, researchers Mayfield and Black created an NLP model to forecast AfD outcomes. Consistent with previous research, they found that the first "vote" (i.e., comment) can generate a "herd effect" and predict outcomes 20 percent or more over the baseline.
Deletion disputes vary among the language Wikipedias. In English Wikipedia, about 20 percent of AfD comments justify their stance with a policy, compared to less than 3 percent in German and Turkish Wikipedia. Long-time Wikipedians play an outsized role in deletion disputes. Although over 160,000 users had spoken up in AfD discussions, over half the debate comments were made by only 1,218 users. This dominance of veteran editors has increased over time.
Contentious topics
In English and several other Wikipedias, an Arbitration Committee (ArbCom) handles a variety of intractable disputes, including conflicts among users who edit multiple articles within a topic. The Committee itself defines such a situation as a "contentious topic" and its sanctions may apply expansively to all articles with the topic. Disputes within contentious topics is a distinct area of research, some based on ArbCom cases and others on quantifiable variables.
Some topics appear to be unavoidably polarizing, such as abortion and climate change, although the level of editor conflict may not match the degree of public debate. In addition, a topic may be contentious in one language Wikipedia and not another. A 2014 study identified Israel, Adolf Hitler, The Holocaust, and God as the most hotly debated articles across 10 languages.
Editors have been found to line up in rival camps over contentious articles and topics. It is unclear how much such editors coordinate outside of the Wikipedia platform, contrary to Wikipedia policy. Apparent editor coordination can be detected through discourse analysis, such as the 2020 study of 1,206 contentious articles that found "contentious Wikipedia articles seem to clearly partition others into friends (those who have the same opinion on a given topic) and enemies." At the same time, Wikipedians can enhance their reputations with successful editing, which can influence other editors into like-minded approaches to a contentious topic. The most reputable editors tend to write lasting content and they are less involved in disputes.
In an analysis of 5,414 editor profiles, two types of rival camps were discerned: those whose viewpoints tended to be subsumed and those that tended to be maintained. Those found to "win" an edit war were more likely to ban opposing editors, revert edits, remove competing wikilinks, cite Wikipedia policies, show disrespect, be active in ArbCom proceedings, and especially exert control over cited references. Researchers expressed surprise that Wikipedia policies, designed to ensure balanced viewpoints, were instead leveraged to favor one point-of-view in contentious articles.
Looking at two contentious topics in French Wikipedia, Shroud of Turin and Sigmund Freud, researchers noticed a shift in focus from the editors' conflicting opinions to their disagreements over encyclopedic sources (e.g., are they scientific) and fellow editors (e.g., did they read the sources). Editors argued in adversarial, not collaborative, ways because of personal, non-encyclopedic goals, such as religious commitments, beyond Wikipedia. With Freud, the split among editors could be explained in terms of their competing epistemologies. However, the Shroud of Turin article was vulnerable to the meta-fallacy of bothsideism, according to the case study authors, because the "tenacity" of religious Wikipedians "might simply aim to enable other believers to continue to do so, by illustrating possible lines of argumentative defense, that indeed seem unending".
In a case study of two post-colonial topics, Algeria vs. France, and Gran Colombia vs. Spain, scholars found that the most active, presumably reputable, editors suffered the fewest deletions of their writing. Moreover, evidence suggested that fewer deletions were made by those who make use of Talk pages, as recommended by Wikipedia policy. The two ingroups with the most Wikipedians France and Gran Colombia were more likely to delete contributions by their presumed opposition from Algeria and Spain, respectively.
Dispute resolution
Soon after its founding, Wikipedia provided avenues to resolve content and conduct disputes. Just as editing disputes are difficult to define precisely, scholars have disagreed about identifying when disputes are resolved. Yasseri et al. categorized articles into three levels of disputation: Consensus, "Sequence of temporary consensuses", and "Never-ending wars".
For content disagreements, Wikipedia has experimented with a variety of mechanisms. Experienced editors have been found to reduce reverts by citing Wikipedia policies, especially "Neutral point of view" (NPOV), "Consensus", and "No original research". Editing disagreements may be resolved by argumentation, compromise, and explaining previous discussions. As of 2024, editors may pursue dispute resolution by requesting a third party opinion, an informal arrangement intended for two editors in disagreement.
If their dispute remains unresolved, another recourse is the Dispute Resolution Noticeboard (DRN). The DRN approach does not offer formal closure or a binding compromise, but many cases are rejected for not pursuing other avenues, so it has become less useful. Of 2,520 DRN cases through mid-2020, there were 237 successful resolutions, 149 failures, and 2,134 (85%) closed without a result.
Moreover, editors may submit content disagreements into the Requests for Comment (RfC) system. These requests, circulated to uninvolved editors by a bot, benefit from the RfC's distinctive structure and the imposition of a 30-day deadline. During a seven year period, (English) Wikipedia had over 7,300 requests for comment discussions. RfC discussions are often closed with a Wikipedia-style "consensus" on the content dispute. However, a significant number "go stale" because they are ignored by veteran editors or, conversely, the RfCs are overwhelmed with comments and too complex or controversial to be closed.
In the past, editors in unresolved content disputes could file for formal mediation by a Mediation Committee, which was discontinued due to inactivity in 2018. Dispute resolution was also provided by informal groups such as the "Mediation Cabal". A 2010 study, cited by Ren et al., found that "mediators can alter the text discussion between conflicting editors (e.g., by striking through some statements), clarify ambiguity, differentiate between personal and substantive arguments, and show the editors how their exchanges could be made more constructive. They can also help manage temporal discontinuities (i.e., when one party is unavailable, the other party may make misattributions), and reduce power differences among editors."
For user conduct issues, in 2003, Jimmy Wales created the Arbitration Committee (ArbCom), an overarching authority for binding resolution of conduct disputes. ArbCom cases are structured in a formal, though it tends to be flexible and informal as it works toward decisions. More than 500 complaints were submitted to ArbCom between 2004 through 2020. ArbCom examines evidence of misconduct but its decisions have been criticized for favoring the more socially effective parties.
History of disputes on Wikipedia
One of the first large-scale disputes about Wikipedia was an internal argument over advertising, starting with Larry Sanger and dissent by Spanish editors, which led to a 2002 fork of the Spanish Wikipedia. Edit warring gave rise to the rule against three repeated reverts by the same editor. In 2005–2006, Wikipedians debated whether to display controversial images from the Jyllands-Posten Muhammad cartoons. On internal matters, early disputes included the 2006 userbox controversy, which was resolved partly by placing templates in personal user pages and partly by administration actions by Jimmy Wales.
Meanwhile, in its first decade, Wikipedia set up dispute resolution mechanisms, including the Arbitration Committee, and refined policies to govern and reduce disputes. In its second decade, the Wikimedia Foundation funded and tracked research on disputes. Some Wikipedia dispute resolution efforts were disbanded. A Universal Code of Conduct for all Wikipedia organizations is designed to restrain the most egregious actions, some of which may arise from editing disputes.
See also
Ideological bias on Wikipedia
List of edit wars on Wikipedia
List of Wikipedia controversies (including some disputes among Wikipedia editors)
Further reading
Lih, Andrew (March 17, 2009). The Wikipedia Revolution: How a Bunch of Nobodies Created the World's Greatest Encyclopedia. Hyperion. .
Tkacz, Nathaniel. Wikipedia and the Politics of Openness. University of Chicago Press, 2020. ISBN 9780226192444
References
Wikipedia dispute resolution
Wikipedia history
Wikipedia disputes
Dispute resolution
Mediation
Human–computer interaction
Wikipedia content | Disputes on Wikipedia | [
"Engineering"
] | 3,555 | [
"Human–computer interaction",
"Human–machine interaction"
] |
78,013,417 | https://en.wikipedia.org/wiki/Ammonium%20hexachloroplumbate | Ammonium hexachloroplumbate is an inorganic chemical compound with the chemical formula .
Synthesis
Adding ammonium chloride to a solution of lead(IV) tetraacetate in concentrated hydrochloric acid.
Physical properties
Ammonium hexachloroplumbate forms yellow crystals of cubic system.
The compound is slightly soluble in cold water and decomposes in hot water.
Chemical properties
When added to cold concentrated sulphuric acid, the compound decomposes, yielding :
The compound chlorinates tetraorganolead and hexaorganodilead compounds.
References
Chloro complexes
Ammonium compounds
Chlorometallates | Ammonium hexachloroplumbate | [
"Chemistry"
] | 135 | [
"Ammonium compounds",
"Salts"
] |
78,013,627 | https://en.wikipedia.org/wiki/Drone-Enhanced%20Emergency%20Medical%20Services | Drone-enhanced Emergency Medical Services (DEMS) involve the use of highly autonomous Beyond Visual Line of Sight (BVLOS) drones to deliver critical medical supplies, such as Automated External Defibrillators (AEDs), life-saving medications, and remote diagnostic equipment, directly to emergency situations. This innovative approach is gaining traction globally, as it significantly reduces response times, thereby improving patient outcomes in time-sensitive scenarios like cardiac arrests and other emergencies where every second counts.
The evolution of drone technology in EMS has been fueled by advancements in unmanned aerial systems (UAS) and the growing recognition of their capabilities in addressing logistical challenges, particularly in remote or underserved areas. Initial trials in the early 2010s laid the groundwork for delivering medical supplies, while subsequent pilot programs have focused on specialized applications, including rapid delivery of emergency medical equipment and live video feeds to support first responders before their arrival at the scene. Despite the promising benefits of drone-enhanced EMS, some challenges remain, including public acceptance, regulatory hurdles, and the technological complexity of integrating these systems into existing emergency response frameworks. As healthcare organizations seek innovative solutions to improve emergency medical responses, addressing these challenges will be crucial.
History
The concept of using drones in emergency medical services (EMS) has evolved significantly over the past decade, driven by advancements in drone technology and the growing recognition of their potential in healthcare. Initially, drones were primarily used for military operations and recreational activities. However, their versatility has led to a broader range of use cases, including EMS.
Early developments
The use of drones for healthcare logistics can be traced back to early trials in the 2010s, which focused on delivering medical supplies to remote areas, aiming to address logistical challenges such as extreme weather, natural disasters, and limited transport infrastructure. These early implementations demonstrated the potential for drones to significantly improve medical delivery efficiency, particularly in emergencies where time is critical.
Expansion into Emergency medicine
As drone technology matured, EMS began to explore more specialized applications. By the mid-2010s, pilot programs were developed to test drones for the delivery of critical medical supplies, such as Automated External Defibrillators (AEDs), particularly for out-of-hospital cardiac arrest cases. These programs often involved collaboration between healthcare providers, technology developers, and regulatory agencies to ensure safety and operational compliance.
Future directions
Today, drones are increasingly being integrated into EMS, with applications ranging from rapid assessment of emergency situations to delivering medical supplies like AEDs and medical supplies and remote diagnostic equipment. The potential of drone technology continues to expand as regulatory frameworks evolve, and ongoing research promises further innovations in the field.
Technology
The technology behind drone-enhanced emergency medical services (DEMS) leverages advancements in unmanned aerial systems (UAS), enabling the rapid and autonomous delivery of medical supplies to incident sites before regular units arrive on scene. These drones operate Beyond Visual Line of Sight (BVLOS), allowing them to respond faster, cover greater distances, often equipped with advanced navigation systems, sensors, and real-time data transmission capabilities.
Adaptations for medical deliveries
The drones used in DEMS are often modified to meet healthcare-specific requirements. Delivery solutions are designed to carry a flexible payload adaptable to local conditions and needs. These adaptations ensure that sensitive medical materials can be delivered safely and effectively in an emergency.
Operational challenges
Despite their effectiveness, drones face several operational challenges. Factors such as weather conditions, battery life, and payload capacity can limit the performance of drones in emergency medical applications. However, ongoing advancements in drone technology aim to overcome these limitations. Some of these innovations include more efficient batteries, better obstacle detection systems, and improved communication networks that allow for more reliable operation in adverse conditions.
Real-time data transmission
In addition to delivering physical medical supplies, drones used in DEMS are often equipped with high-definition cameras and sensors, providing live video feeds and biometric data to emergency responders. This allows healthcare professionals to assess the situation remotely and guide on-site interventions before physical responders arrive.
Applications
Medical supply deliveries
Drones are being used in the rapid transportation of medical supplies in emergencies. For example, healthcare drones have been adapted to carry critical items such as defibrillators (AEDs), pharmaceuticals, anti bleeding equipment and remote diagnostic equipment which can make a significant difference in emergency response scenarios.
Emergency response and disaster relief
In emergency medical situations, such as out-of-hospital cardiac arrests, drones have been deployed to deliver AEDs quickly to the scene. Studies show that AED-equipped drones can reduce response times compared to traditional ground transportation. This reduction in time is crucial for improving patient outcomes, particularly in cardiac arrest cases where immediate defibrillation can save lives.
Drones have also been used in disaster relief, where they can rapidly deliver medical supplies to hard-to-reach areas following natural disasters or large-scale emergencies. These drones can fly over blocked roads and other obstacles, ensuring that medical help reaches those in need as quickly as possible.
Remote patient monitoring and telemedicine
Drones are also being used to support telemedicine and remote patient monitoring. By transmitting real-time video feeds and biometric data from delivered devices, enables healthcare professionals to assess patients' conditions remotely and provide real-time consultation and diagnosis. This is particularly useful in areas with limited healthcare resources, allowing for more timely interventions and support.
AED-drone trials
Several trials have evaluated the effectiveness of drones delivering AEDs in real-life cardiac arrest situations. A Swedish study in 2020-2023 reported that drones arrived before ambulances in 57% of cases, and AEDs were attached by bystanders in 35% of these cases. These drones achieved a 92% success rate in delivering AEDs within 9 meters of the target. The real-life case study published in the New England Journal of Medicine showed that a drone-delivered AED was successfully used to defibrillate a cardiac arrest patient before emergency medical services arrived.
See also
Unmanned Aerial Vehicle
Emergency Medical Services
References
Medicine | Drone-Enhanced Emergency Medical Services | [
"Biology"
] | 1,209 | [
"Medicine"
] |
78,014,319 | https://en.wikipedia.org/wiki/Baddies%20in%20Tech | Baddies in Tech is an American organization that provides a safe space for Black women in the technology sectors to network and grow their careers. The founding of Baddies in Tech in 2019 led to the creation of BaddieCon.
Organization
Baddies in Tech is a nonprofit DAO founded by Allie Joy Tsahey in 2019. Baddies in Tech's mission is “to build a public good that empowers and uplifts Black and brown female technologists globally.” Baddies in Tech also provide a database of resources for those looking for employment opportunities. Furthermore, the Baddies in Tech organization hosts events and tech conferences geared toward providing women a safe place to come together. Baddies in Tech maintains a Discord server as a place of conversation for their community.
References
Data and information organizations
Ethics of science and technology
Diversity in computing | Baddies in Tech | [
"Technology"
] | 170 | [
"Diversity in computing",
"Computing and society",
"Data",
"Ethics of science and technology",
"Data and information organizations"
] |
78,014,467 | https://en.wikipedia.org/wiki/Opus%20scutulatum | Opus scutulatum, literally "shield work", is a type of masonry construction used in Roman architecture. It consists of irregular chunks of stone or polychrome marbles on a background of white tesserae lacking figural decoration.
Description
A mosaic floor in opus scutulatum, also called crustae or lithostroton, consists of an almost always monochrome background with inlaid larger scutulae, literally “shields”. These scutulae consist of marble stone fragments of various sizes, colours and shapes. The fragments exist in many shapes; in addition to rectangular ones, triangular and diamond-shaped stones are common. The mosaics of the scutulatum style have the appearance of a simple mosaic pavement lacking figural decoration and were in use throughout the entire Roman Empire.
Pliny (Naturalis Historia XXXV.185) reports that opus scutulatum was first used in Rome at the beginning of the Third Punic War (149 BC) in the Temple of Jupiter Capitolinus.
References
Building stone
Pavements
Architectural elements
Ancient Roman construction techniques | Opus scutulatum | [
"Technology",
"Engineering"
] | 221 | [
"Building engineering",
"Architectural elements",
"Components",
"Architecture"
] |
78,014,902 | https://en.wikipedia.org/wiki/Caproate%20fermentation | Caproate fermentation is a metabolic process used by different bacteria to utilize different organic substrates for the production of caproic acid (hexanoic acid) as well as other valuable byproducts. Caproic acid is a valuable compound in food industries as a flavor additive, feedstock for chemical industries, antimicrobial agents in the pharmaceutical industry, and more. Though this process is used by varying bacterial species, the most common species utilizing caproate fermentation in its metabolic process is Clostridium kluyveri. This species, as well as others, utilize caproate fermentation through the breakdown of varying substrates for energy production, waste management and increased ability for survival in different environments.
Chemical structures and properties
Chemical Structure
Caproic acid is otherwise known as hexanoic acid. In solid state, the acid appears as a white crystalline structure, while when liquid, it appears clear with a yellow tint. Any contact with caproic acid will cause irritation to various parts of the body and is toxic to humans. The acid is formed through β-oxidation which elongates a short chain carboxylic acid origin using lactic acid as the electron donor to drive the process. This is done through a series of reactions driven by varying enzymes.
Chemical methods
Carboxylic acids and alcohols are required as substrates for caproate fermentation. Due to the danger of high concentrations in these substrates, they must be diluted. This danger factor results in more materials needed and a more meticulous process to perform fermentation, which is costly. Recent studies suggest that food waste can serve as an alternative source for these substrates, potentially reducing cost and waste. The interest in creating more efficient methods for producing caproates—specifically n-caproate (hexanoate) and n-caprylate (octanoate)—has been challenged by the natural efficiency of C. kluyveri. There are many different ways to produce caproate fermentation however, it is difficult to avoid disruption of the cell and effectively produce caproate. To efficiently produce caproate, optimal conditions are required including: pH, temperature, and environmental concentration.
Process of Fermentation
Certain bacterial species convert carbohydrates (like glucose) into caproate (hexanoate), a six-carbon fatty acid.
Throughout this process of fermentation, bacteria anaerobically break down carbohydrates like glucose through a series of biochemical reactions producing caproate. Furthermore, chain elongation of ethanol and acetate is also needed to create caproate. Ethanol is toxic to many bacterial species, so the ethanol must be pretty balanced in the process to ensure caproate production. Studies have found that with an ethanol/acetate ratio higher than 7:3 require no extra electron donors and a 10:1 ratio produced 8.42g/L of caproate. Additional byproducts are formed like hydrogen gas, carbon dioxide, and sometimes butyrate or acetate. Caproate is the main product, hence the name of caproate fermentation.
Function and Usage
Caproic acid a straight-chain saturated fatty acid has a use in many different areas. These areas being things like artificial flavoring because of its esters. This acid is found in different kind of fats and oils of animals. Not only for flavoring but caproic acid can be used in different medicinal applications as well. Caproic acid is used widely by the agricultural industry and can also be used in antibiotics and as lubricants. More recent studies have proposed the idea that caproic acid can be used to ferment organic waste. Considering that organic waste is 46% of the total waste produced each year.
Research and Industry
Following the Covid-19 pandemic, an international market for medium chain carboxylic acids like caproic acid has emerged. This market is estimated to grow to 358.8 million US dollars by 2030. Caproic acid, a MCCA (medium-chain carboxylic acid) having a multitude of implementations that include cosmetics, solvents, fuels, and antibiotic growth-promoting substitutes in animal feed. With such optimistic market growth being estimated, research surrounding the synthesis of caproic acids has increased and new methods are being explored. Among the methods being looked at is caproate fermentation through microbial cultures.
References
Wikipedia Student Program
Metabolism | Caproate fermentation | [
"Chemistry",
"Biology"
] | 930 | [
"Biochemistry",
"Metabolism",
"Cellular processes"
] |
78,015,277 | https://en.wikipedia.org/wiki/Elsa%20Abuin | Elsa Beatriz Abuin Saccomano (13 December 1942 – 18 April 2012) was an Argentine chemist. After fleeing the country due to La Noche de los Bastones Largos, she became a professor at University of Chile. A 1987 Guggenheim Fellow, she specialized in physical chemistry, especially in chemical kinetics.
Biography
Elsa Beatriz Abuin Saccomano was born on 13 December 1942 in Buenos Aires, Argentina. After getting her BS in Chemistry at the University of Buenos Aires in 1966, she intended to do her graduate studies in Argentina, before her research group fled the country due to the La Noche de los Bastones Largos. Led by Juan Grotewold and Eduardo Lissi, the Grotewold-Lissi group later settled at the Technical University of the State (UTE), where she was a professor at the Department of Engineering and got her PhD in Chemistry in 1974; her dissertation Fotoquímica de cetonas alifáticas en fase gaseosa was supervised by Lissi, and they would later author well over a dozen articles together afterwards.
Originally a teaching assistant, she later remained in TUE as part of their Kinetics and Photochemistry research group, as well as a full professor of chemistry, as a research scientist, and as director of the Faculty of Chemistry and Biology's graduate program. She also spent time abroad as a visiting professor at the National University of Río Cuarto and University of São Paulo.
As an academic, she specialized in physical chemistry, especially in chemical kinetics. In 1987, she published Macromoleculas en Solución, a UNESCO monograph. A long time contributor to the University of Santiago's series on physical chemistry books, she edited the fourth volume, which was published after her death in 2013. The journal Photochemistry and Photobiology said that she "was, without any doubt, a pillar in the development and consolidation of the chemical sciences in Chile".
In 1987, she was awarded a Guggenheim Fellowship for "a study of fluorescence probing of colloidal particles". she was the first Chilean woman to receive the fellowship. As part of the Fellowship, she did research in North America at the University of Rochester and University of Ottawa, the latter of where she worked under Tito Scaiano.
She also co-founded the Encuentros Latinoamericanos de Fotoquímica y Fotobiología conference and was an organizer as late as the 2010 conference.
Abuin died in 18 April 2012. Photochemistry and Photobiology published a special memorial issue dedicated to Abuin.
References
1942 births
2012 deaths
Physical chemists
Women physical chemists
Argentine chemists
20th-century Argentine scientists
20th-century Argentine women scientists
People from Buenos Aires
University of Buenos Aires alumni
University of Chile alumni
Academic staff of the University of Chile
Argentine exiles
Argentine expatriates in Chile
Expatriate academics | Elsa Abuin | [
"Chemistry"
] | 594 | [
"Women physical chemists",
"Physical chemists"
] |
78,018,326 | https://en.wikipedia.org/wiki/Sherry%20Suyu | Sherry H. Suyu is a Canadian observational cosmologist whose research uses gravitational lensing of supernovae and quasars to study the expansion of the universe. She works in Germany as a Max Planck Fellow at the Max Planck Institute for Astrophysics, associate professor and head of the Observational Cosmology group at the Technical University of Munich, and leader of the H0LiCOW and HOLISMOKES collaborations for gravitational lensing of quasars and supernovae respectively.
Education and career
Suyu grew up in Canada, and is a 2001 graduate of Queen's University at Kingston in Canada. She completed a Ph.D. at the California Institute of Technology in 2008. Her doctoral dissertation, Dissecting the gravitational lens B1608+656: Implications for the Hubble constant, was jointly supervised by Roger Blandford and Kip Thorne.
After postdoctoral research at the University of Bonn, University of California, Santa Barbara, and Stanford University, she worked as a faculty member at the Academia Sinica Institute of Astronomy and Astrophysics in Taiwan from 2013 to 2016, close to her parents. She returned to Germany in 2016 with a joint position at the Max Planck Institute for Astrophysics and Technical University of Munich. In 2022 she was promoted to associate professor and Max Planck Fellow.
Recognition
Suyu received the Significant Research Achievements Award of the Academia Sinica in 2013. She was the 2021 recipient of the Lancelot M. Berkeley − New York Community Trust Prize for Meritorious Work in Astronomy of the American Astronomical Society. In 2022, the Technical University of Munich gave her its Heinz Maier-Leibnitz Medal.
References
External links
Home page
Year of birth missing (living people)
Living people
Canadian cosmologists
Canadian women physicists
Women astronomers
Queen's University at Kingston alumni
California Institute of Technology alumni
Academic staff of the Technical University of Munich
Max Planck Institutes researchers | Sherry Suyu | [
"Astronomy"
] | 382 | [
"Women astronomers",
"Astronomers"
] |
78,021,309 | https://en.wikipedia.org/wiki/Priority%20Services%20Register | In the United Kingdom, Priority Services Registers are maintained by gas, electricity and water utilities as a means of ensuring that vulnerable customers are protected. Registration is free.
Benefits of registration include availability of temporary supplies in the event of an outage, protection from bogus callers, and assistance with understanding and paying bills.
According to Yorkshire Water Services, households are eligible for registration where, for example:
someone has limited mobility or cannot leave their home
someone has communication difficulties such as with their sight, speech or hearing
there is a person with a learning disability
someone has dementia
a family has a child under five years of age
a person has difficulties with paying their bills.
In the gas and electricity markets, Priority Services Registers are maintained by the supply companies and distribution network operators, and their use is endorsed by Ofgem. Water companies operate Priority Services Registers in accordance with guidance issued by Ofwat. In the gas industry, the register has a statutory definition:
References
Customer service
Water industry
Energy companies of the United Kingdom | Priority Services Register | [
"Environmental_science"
] | 202 | [
"Hydrology",
"Water industry"
] |
78,021,654 | https://en.wikipedia.org/wiki/BioLab%20Inc. | BioLab Inc. is a division of KiK Consumer Products that specializes in the manufacturing of chemicals for use in swimming pools. The company has faced ongoing scrutiny regarding its problematic safety record, most recently following a fire at its Conyers, Georgia plant which put 90,000 citizens of the region under shelter-in-place restrictions.
Company history
BioLab was founded in 1955 by Leon Bloom. Originally, it provided cleaning products to the poultry industry. The company pivoted into pool and spa chemicals with the release of BioGuard in 1962. It was sold to the Lonza group in 1979, after which Bloom retired. The company was then purchased in 1996 by Great Lakes Chemical Corporation which became Chemtura in a merger with Crompton Corporation. After Chemtura's bankruptcy, the company was acquired by Canadian company KiK consumer products, in January 2014, for a sum of 300 million.
In 2003, the company's headquarters moved to Lawrenceville, GA. At the time of Chemtura's bankruptcy, BioLab employed 4,750 employees, most of which were employed at facilities in Lawrenceville.
Louisiana plant
The company acquired its Lake Charles, Louisiana plant in 2013. The original facility had been built in 1979, but was destroyed in 2020 after flooding from Hurricane Laura resulted in water coming into contact with water-reactive chemicals and burned the plant down. At the time of the fire, the plant was the second largest producer of trichloroisocyanuric acid (TCCA) and disodium isocyanurate. The plant being offline, compounded by the 2020 COVID pandemic, resulted in supply shortages that stretched into 2022. This plant was rebuilt in neighboring Westlake, Louisiana, following a $170M investment from KiK. Construction on the site started in June 2021 and the plant reopened in July 2022. In March 2023, a chlorine leak from a pipe in the facility resulted in a shelter in place order and the temporary shutting down of interstate I-10. In July 2024, the Louisiana site warehouse caught fire, resulting in a temporary shutdown of interstate I-10.
Conyers plant
The company's Conyers plant was founded in 1973. At the time of the 2024 fire, the plant was Rockdale County's 8th largest employer, with 484 employees, as well as the company with the highest assessed property value at $113.4 million, representing 3% of the total assessed value of the county.
2004 Conyers plant fire
On May 25, 2004, Plant 14 warehouse caught on fire. The building which housed roughly 12.5 million pounds of pool chemicals and oxidizers, was a total loss. The fire resulted in the mandatory evacuation of citizens within a 1.5 mile radius, and the closure of I-20, as well as a voluntary evacuation of citizens north of the now-closed highway. Media reported that 28 people visited hospitals as a result of the fire, with no major injuries.
More than 150 firefighters were involved in fighting the blaze, using nearly 10 million gallons of water, which required Rockdale county to purchase water from nearby DeKalb county to refill its water capacity. Losses for the company were estimated to be in excess of $50 million. The site of the warehouse was later redeveloped into another warehouse, breaking ground in 2019, which subsequently burned down in the 2024 fire.
2020 Conyers plant fire
On September 14, 2020, a pipe connecting to a hot-water heater leaked, causing flooding in Plant 6 of the Conyers BioLab complex. The water came into contact with TCCA present on the floor, resulting in the flood water becoming milky-white. This was noticed by employees but soon afterwards began an exothermic decomposition. An employee wearing a respirator attempted to remove non-decomposing bags of TCCA in an attempt to isolate bags undergoing decomposition. After roughly 10 pallets had been moved, deteriorating conditions inside the warehouse made further removal too hazardous.
Rockdale County firefighters used water to spray decomposing bags of TCCA in the hopes of keeping the temperature of the reaction lower than the combustion temperature of the material. While no TCCA is reported to have caught on fire during this incident, decomposition vapors lead nine of the firefighters to be placed under observation at a local hospital. The total damage was estimated at over a million dollars.
Four days later, some of the TCCA that had been relocated to a semi-trailer caught on fire.
2024 Conyers plant fire
On the morning of September 29, 2024, at around 5a.m. EDT, a fire broke out on the roof of a warehouse in the Conyers complex, caused by a malfunctioning fire sprinkler, which drenched TCCA in water, causing a runaway fire and decomposition that sent upwards massive clouds of orange and black smoke. This smoke was visible from Hartsfield–Jackson Atlanta International Airport, away from the fire. The warehouse walls and roof later collapsed, and the fire was brought under control by 4 pm, although decomposition reactions producing toxic gasses were still happening.
The massive cloud of smoke and toxic decomposition products sparked evacuations and shelter-in-place orders for neighboring areas.
Interstate 20 in Georgia was closed due to the event. Residents of Conyers were ordered to evacuate, and a shelter-in-place order was put into effect for all of Rockdale County. EPA air monitoring systems in the area detected chlorine, chloramine, and chlorine compounds produced by the decomposition of TCCA. Areas in Fulton County, Georgia reported a "haze and strong chemical smell".
Drifting clouds of gas forced the evacuation of some Piedmont Rockdale Hospital patients to Newton Hospital away, though the latter also faced a shelter-in-place order a few hours later.
In the week before the fire, the area had experienced the effects of Hurricane Helene, which brought heavy rain, winds, and flooding to the region, but it is unknown whether the storm had any influence on the fire.
By October 1, six lawsuits had been filed against BioLab and its parent company. Meanwhile, the Rockdale Emergency Management Agency (EMA) issued a daily 7 am to 7 pm shelter-in-place recommendation until Friday, October 4. They cautioned that, due to the effects of weather and inversion layers, air quality could worsen to "concerning levels" at night.
On October 3, the American Red Cross opened a shelter for evacuated residents at Fairview Recreation Center in Stockbridge, Georgia, roughly southwest of Conyers.
As of October 14, the EPA is providing updated air quality reports for Rockdale County every 12 hours.
Other incidents
A 2015 fire in an outside storage area of the plant was rapidly contained by Rockdale County Firefighters, but resulted in six firefighters being treated for non-life-threatening injuries.
Smaller fires were also reported in 2010 and 2016.
References
1955 establishments in Georgia (U.S. state)
American companies established in 1955
Chemical companies established in 1955
Chemical companies of the United States
Manufacturing companies based in Georgia (U.S. state)
Chemical disasters
Fires in Georgia (U.S. state)
Fires in Louisiana
Industrial fires and explosions in the United States
Rockdale County, Georgia
Lake Charles, Louisiana | BioLab Inc. | [
"Chemistry"
] | 1,487 | [
"Chemical accident",
"Chemical disasters"
] |
78,023,401 | https://en.wikipedia.org/wiki/Grevillea%20milleriana | Grevillea milleriana is a flowering plant in the family Proteaceae native to a restricted distribution in the Maddens Plains area in New South Wales, Australia. It is currently only known from the holotype specimen.
Description
Grevillea milleriana is a low, spreading, sub-prostrate shrub which typically grows up to high and wide, with the lowest branches trailing along the ground. The leaves are long and wide and are either lobed or entire with up to 8 broadly triangular lobes. The upper surface of the leaves is glabrous or nearly so and the lower surface of the leaves is silky hairy. The flowers are arranged in groups near the ends of branches, long and about wide on a peduncle long, each flower on a pedicel long. The perianth is long, pink outside and purplish-pink inside with a brown, limb long. The style is glabrous and the pollen-presenter is long and wide.
Similar species
Grevillea milleriana is closely related to G. barklyana, G. macleayana and G. gilmourii, another species described in the same year. It can be distinguished from its relatives by its low, spreading habit, its longer pedicels () long and shorter anthers long.
Taxonomy
Grevillea milleriana was first formally described by Peter M. Olde in the journal Telopea from specimens collected near Maddens Plains in 2021. The specific epithet (milleriana) honours the discoverers of the species, R. T. Miller and Janice Miller.
The holotype was previously misidentified as a disjunct population of G. caleyi, a species which only occurs within the Terrey Hills region north of Sydney.
References
milleriana
Endemic flora of Australia
Flora of New South Wales
Proteales of Australia
Plants described in 2022
Species known from a single specimen | Grevillea milleriana | [
"Biology"
] | 386 | [
"Individual organisms",
"Species known from a single specimen"
] |
78,023,415 | https://en.wikipedia.org/wiki/Markarian%201018 | Markarian 1018 (Mrk 1018), also known as UGC 1597, is a lenticular galaxy with a peculiar structure located in the constellation Cetus. It is located at an approximate distance of 607 million light years from Earth and has an apparent dimensions of 0.99 by 0.52 arcmin. It is classified as a change looking Seyfert galaxy and galaxy merger.
Characteristics
Markarian 1018 is a post merger product of two colliding galaxies indicated by the presence of its disturbed galactic envelope, tidal tails and a faint loop of light surrounding it. It has a stellar mass measured as log M*/Mʘ = 10.92 and a total star formation of 0.6
Mʘ yr−1. It has an active galactic nucleus (AGN) like most types of active galaxies with the energy source originating from an accretion disk around its supermassive black hole. The mass of the black hole in Markarian 1018 varies however. In a 2011 study, its mass is around log (MBH/Mʘ) = 8.15 . But later studies showed the mass is (MBH/Mʘ) = 7.4. and subsequently (MBH/Mʘ) = 7.84.
The appearance of Markarian 1018 is known to shift from a bright to a dim state when observed in X-rays as well as both optical and ultraviolet models detected by Hubble Space Telescope, Sloan Digital Sky Survey and GALEX. This is likely caused by the disruption of the fueling of its black hole by an interaction of a likely secondary black hole in the galaxy.
The AGN of Markarian 1018 is described change looking. It was originally a type 1.9 Seyfert galaxy. Between the years 1979 and 1984, it underwent a transition to become a type I. During the change, its ultraviolet and optical line emission strengthened. However, Markarian 1018 has since changed back into type 1.9 after a period of 30 years. Its broad line flux declined with a Hα factor of 4.75 ± 0.5 while its broad emission lines vanished. This makes the galaxy the first known change looking AGN to undergo two transitions in a full cycle. It also shows a very weak continuum with the presence of indistinctive Hα and Hβ emission lines best fitted by a line component with a measurement of FWHM ≈ 7200 km s−1.
The X-ray source of Markarian 1018 has gone through a spectral variation. Between 2005 and 2019, its hardness ratio significantly increased from 0.2 ± 0.1 to 0.4 ± 0.1, between both the 0.5-2 and 2-10 keV bands. In additional, the broadband in the galaxy became dim, as the X-ray, ultraviolet and optical luminosities went down by factors of > 7, > 24 and ~ 9. This sharp decrease is suggested by lower ultraviolet emission. Further evidence also points out the hot medium properties of Markarian 1018 clearly remains the same while a warm component is found to cool down to a temperature of ~ 0.2 keV, suggesting the cooling process plays a major role in weakening the accretion disk's magnetic fields and the cause of ultraviolet dimming.
In late 2016, Markarian 1018 suddenly stopped dimming. It underwent a flaring period in which the galaxy showed an outburst; its magnitude level rising by ~ 0.25 U-band per month until early 2017 according to confirmation from Hubble and Chandra X-ray Observatory. Following resumption of monitoring in July 2017, it has since been only found ~ 0.4 magnitude higher than its flaring period. It has since gone through another outburst this time in 2020. While much of its optical spectrum and primary X-ray flux remained constant, its 6.4 keV iron line strengthened through increased emission. This suggests the accretion rate in Markarian 1018 has changed drastically in short-term.
References
External links
Mrk 1018 on SIMBAD
Markarian galaxies
01597
08029
+00-06-030
Seyfert galaxies
Active galaxies
Lenticular galaxies
Galaxy mergers | Markarian 1018 | [
"Astronomy"
] | 848 | [
"Cetus",
"Constellations"
] |
78,024,047 | https://en.wikipedia.org/wiki/Hezbollah%20tunnels | Hezbollah's underground tunnels (or Hezbollah Tunnels Network or Hezbollah's Underground Facilities, ) refer to a network of underground passages used by Hezbollah, primarily in southern Lebanon, along the Lebanon-Israel border. These tunnels are often used for military purposes, such as smuggling weapons, storing supplies, and allowing fighters to move discreetly. The tunnels have been a significant concern for Israel, which views them as a direct security threat. The presence of tunnels near the so-called blue line, as well as incursions into Lebanese territory by other countries, constitute a violation of UN Resolution 1701, such violations contribute to the ongoing tensions between Israel and Hezbollah.
History
Nicholas Blanford, a Beirut-based Hezbollah expert considers that Hezbollah's tunnel networks began in the mid-1980s after the 1982 Lebanon War resulting from the invasion of Lebanon by Israel that led to the creation of the Hezbollah. These tunnels were used shortly after launching its own military operations against the occupation state in the 1990s. However, the investment in tunnel construction has been increased since the early 2000s, due partially to the armed conflict with the South Lebanon Army and military operations against Israeli military posts in occupied Lebanese territory, and particularly since the 2006 Lebanon War. Israel has conducted operations to locate and destroy these tunnels, viewing them as a significant threat to its security.
Operation Northern Shield
In December 2018, Israel launched "Operation Northern Shield" to detect and destroy the tunnels. In recent years, the Israeli Defense Forces (IDF) claimed to have found and destroyed several tunnels crossing the border from Lebanon into Israel.
UN involvement
With the resolution 1701 of the Security Council agreed in 2006, the blue line was used to monitor the withdrawal of Israeli forces from southern Lebanon and the activities of armed groups. The resolution states that the area must be free of arms and armed personnel except for the Lebanese armed forces and UN peacekeepers, and no foreign forces can be present in Lebanon without the consent of its government. The United Nations Interim Force in Lebanon (UNIFIL) is responsible for ensuring compliance by all parties with this resolution and has reported violations of resolution UN 1701 by both sides, Israel and Hezbollah, according to the Security Council reports.
The UNIFIL was able to confirm the existence of only three of the tunnels that were reported by IDF. UNIFIL also confirmed that an old concrete factory in Kfar Kela had an opening to the tunnel, which crossed the Blue Line.
Purposes
These tunnels serve various purposes, including:
Military Operations: They allow Hezbollah fighters to move undetected and launch surprise attacks against Israeli forces.
Smuggling: The tunnels are used for smuggling weapons and supplies, often circumventing Israeli surveillance.
Shelter: They provide protection for fighters during airstrikes or ground operations.
Logistics: The network facilitates communication and transportation of goods and personnel.
See also
United Nations Interim Force in Lebanon
Hezbollah
South Lebanon conflict (1985–2000)
Israeli occupation of Southern Lebanon
References
Tunnel warfare
Hezbollah–Israel conflict
Israel–Lebanon border
Tunnels in Lebanon | Hezbollah tunnels | [
"Engineering"
] | 599 | [
"Military engineering",
"Tunnel warfare"
] |
78,024,473 | https://en.wikipedia.org/wiki/Cryptic%20plasmids | In molecular biology, a cryptic plasmid is a plasmid that doesn't appear to provide any clear advantage to its host, yet still persists in bacterial populations. These plasmids appear to lack any genetic functions of interest and do not seem to contain genes that could provide beneficial functions to their hosts. Given the lack of a clear advantage to their hosts and the likely cost of maintaining them, these plasmids are often referred to as selfish elements or genetic parasites.The maintenance of cryptic plasmids might be explained by mechanisms like horizontal gene transfer (e.g., conjugation, transduction) that balance their loss due to segregation. However, cryptic plasmids could potentially be important in antibiotic resistance, by contributing to heteroresistance in bacterial populations.
They have been found to be highly abundant, as seen in Lactobacillus where most plasmids are cryptic.
References
Gene delivery
Molecular biology
Mobile genetic elements | Cryptic plasmids | [
"Chemistry",
"Biology"
] | 203 | [
"Genetics techniques",
"Mobile genetic elements",
"Molecular and cellular biology stubs",
"Biochemistry stubs",
"Molecular biology techniques",
"Molecular genetics",
"Molecular biology",
"Biochemistry",
"Gene delivery"
] |
61,341,549 | https://en.wikipedia.org/wiki/Oana%20Caruana%20Pulpan | Oana Caruana Pulpan (born 17 April 1978) is a Maltese chess player. She was awarded the Woman FIDE Master title in 2009. She is a member of the Maltese Women's National Team. Her father introduced her to chess when she was very young and has been playing it since.
She is sponsored by the company she works with, Actavis. She is also a pharmacologist. She teaches chess classes at St. Catherine's High School in Pembroke, Malta.
References
1978 births
Living people
Chess Woman FIDE Masters
Maltese chess players
Pharmacologists | Oana Caruana Pulpan | [
"Chemistry"
] | 119 | [
"Pharmacology",
"Biochemists",
"Pharmacologists"
] |
61,341,798 | https://en.wikipedia.org/wiki/Exact%20diagonalization | Exact diagonalization (ED) is a numerical technique used in physics to determine the eigenstates and energy eigenvalues of a quantum Hamiltonian. In this technique, a Hamiltonian for a discrete, finite system is expressed in matrix form and diagonalized using a computer. Exact diagonalization is only feasible for systems with a few tens of particles, due to the exponential growth of the Hilbert space dimension with the size of the quantum system. It is frequently employed to study lattice models, including the Hubbard model, Ising model, Heisenberg model, t-J model, and SYK model.
Expectation values from exact diagonalization
After determining the eigenstates and energies of a given Hamiltonian, exact diagonalization can be used to obtain expectation values of observables. For example, if is an observable, its thermal expectation value is
where is the partition function. If the observable can be written down in the initial basis for the problem, then this sum can be evaluated after transforming to the basis of eigenstates.
Green's functions may be evaluated similarly. For example, the retarded Green's function can be written
Exact diagonalization can also be used to determine the time evolution of a system after a quench. Suppose the system has been prepared in an initial state , and then for time evolves under a new Hamiltonian, . The state at time is
Memory requirements
The dimension of the Hilbert space describing a quantum system scales exponentially with system size. For example, consider a system of spins localized on fixed lattice sites. The dimension of the on-site basis is 2, because the state of each spin can be described as a superposition of spin-up and spin-down, denoted and . The full system has dimension , and the Hamiltonian represented as a matrix has size . This implies that computation time and memory requirements scale very unfavorably in exact diagonalization. In practice, the memory requirements can be reduced by taking advantage of symmetry of the problem, imposing conservation laws, working with sparse matrices, or using other techniques.
Comparison with other techniques
Exact diagonalization is useful for extracting exact information about finite systems. However, often small systems are studied to gain insight into infinite lattice systems. If the diagonalized system is too small, its properties will not reflect the properties of the system in the thermodynamic limit, and the simulation is said to suffer from finite size effects.
Unlike some other exact theory techniques, such as Auxiliary-field Monte Carlo, exact diagonalization obtains Green's functions directly in real time, as opposed to imaginary time. Unlike in these other techniques, exact diagonalization results do not need to be numerically analytically continued. This is an advantage, because numerical analytic continuation is an ill-posed and difficult optimization problem.
Applications
Can be used as an impurity solver for Dynamical mean-field theory techniques.
When combined with finite size scaling, estimating the ground state energy and critical exponents of the 1D transverse-field Ising model.
Studying various properties of the 2D Heisenberg model in a magnetic field, including antiferromagnetism and spin-wave velocity.
Studying the Drude weight of the 2D Hubbard model.
Studying out-of-time-order correlations (OTOCs) and scrambling in the SYK model.
Simulating resonant x-ray spectra of strongly correlated materials.
Implementations
Numerous software packages implementing exact diagonalization of quantum Hamiltonians exist. These include ALPS, DoQo, EdLib, edrixs, Quanty and many others.
Generalizations
Exact diagonalization results from many small clusters can be combined to obtain more accurate information about systems in the thermodynamic limit using the numerical linked cluster expansion.
See also
Lanczos algorithm
References
External links
Quantum Simulation/Exact diagonalization
ALPS full diagonalization tutorial
Exact Diagonalization and Lanczos Method in E. Pavarini, E. Koch and S. Zhang (eds.): Many-Body Methods for Real Materials, Jülich 2019, ISBN 978-3-95806-400-3
Correlated electrons
Materials science
Condensed matter physics
Quantum mechanics | Exact diagonalization | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 848 | [
"Applied and interdisciplinary physics",
"Theoretical physics",
"Phases of matter",
"Quantum mechanics",
"Materials science",
"Condensed matter physics",
"nan",
"Correlated electrons",
"Matter"
] |
61,343,096 | https://en.wikipedia.org/wiki/Trifora | Trifora is a type of three-light window. The trifora usually appears in towers and belfries—on the top floors, where it is necessary to lighten the structure with wider openings.
Overview
The trifora has three openings divided by two small columns or pilasters, on which rest three arches, round or acute. Sometimes, the whole trifora is framed by a further large arch. The space among arches is usually decorated by a coat of arms or a circular opening. Less popular than the mullioned window, the trifora was, however, widely used in the Romanesque, Gothic, and Renaissance periods. Later, the window was mostly forgotten, coming back in vogue in the nineteenth century, in the period of eclecticism and the rediscovery of ancient styles (Neo-Gothic, Neo-Renaissance, and so on). Compared to the mullioned window, the trifora was generally used for larger and more ornate openings.
Gallery
See also
Monofora
Bifora
Quadrifora
Polifora
Diocletian window
References
AA.VV. Enciclopedia dell'Architettura, Garzanti, Milano 1996,
Pevsner, Fleming e Honour, Dizionario di architettura, Utet, Torino 1978 ; ristampato come Dizionario dei termini artistici, Utet Tea, 1994
Architectural elements
Windows | Trifora | [
"Technology",
"Engineering"
] | 293 | [
"Building engineering",
"Architectural elements",
"Components",
"Architecture"
] |
61,343,781 | https://en.wikipedia.org/wiki/Bifora%20%28architecture%29 | In architecture, a bifora is a type of window divided vertically into two openings by a small column or a mullion or a pilaster; the openings are topped by arches, round or pointed. Sometimes the bifora is framed by a further arch; the space between the two arches may be decorated with a coat of arms or a small circular opening (oculus).
The bifora was used in Byzantine architecture, including Italian buildings such as the Basilica of Sant'Apollinare Nuovo, in Ravenna. Typical of the Romanesque and Gothic periods, in which it became an ornamental motif for windows and belfries, the bifora was also often used during the Renaissance period. In Baroque architecture and Neoclassical architecture the bifora was largely forgotten, or replaced by elements like the three openings of the Venetian window. It was also copied in the Moorish architecture in Spain, where it is called (from Arabic ).
It returned in vogue in the nineteenth century in the period of eclecticism and rediscovery of the ancient styles in Gothic Revival and Romanesque Revival architecture.
Gallery
See also
Monofora
Trifora
Quadrifora
Polifora
References
Architectural elements
Windows | Bifora (architecture) | [
"Technology",
"Engineering"
] | 246 | [
"Building engineering",
"Architectural elements",
"Components",
"Architecture"
] |
61,344,228 | https://en.wikipedia.org/wiki/Quadrifora | Quadrifora is a type of four-light window. It appears in towers and belfries on top floors, where it is necessary to lighten the structure with wider openings. The quadrifora can also be a group closely set windows.
Overview
The quadrifora is divided vertically in four parts by three small columns or pilasters, on which four arches rest, round or pointed. Sometimes, the quadrifora is framed by a further larger arch; the space among the arches may be decorated by a coat of arms or a small circular opening.
Less popular than the bifora or trifora, the quadrifora was nevertheless used in the Romanesque, Gothic, and Renaissance periods. In the 19th century, it came back in vogue in the period of eclecticism and the revival of old styles. Compared to the trifora, the quadrifora was generally used for larger and more ornate openings.
Gallery
See also
Monofora
Bifora
Trifora
Polifora
References
Architectural elements
Windows | Quadrifora | [
"Technology",
"Engineering"
] | 211 | [
"Building engineering",
"Architectural elements",
"Components",
"Architecture"
] |
61,344,346 | https://en.wikipedia.org/wiki/Borate%20fluoride | The borate fluorides or fluoroborates are compounds containing borate or complex borate ions along with fluoride ions that form salts with cations such as metals. They are in the broader category of mixed anion compounds. They are not to be confused with tetrafluoroborates (BF4) or the fluorooxoborates which have fluorine bonded to boron.
Examples
References
Borates
Fluorides
Mixed anion compounds | Borate fluoride | [
"Physics",
"Chemistry"
] | 98 | [
"Matter",
"Mixed anion compounds",
"Salts",
"Fluorides",
"Ions"
] |
61,345,171 | https://en.wikipedia.org/wiki/VDM%20Metals | VDM Metals Group (formerly Vereinigte Deutsche Metallwerke) based in Werdohl, Germany, is a manufacturer of corrosion-resistant, heat-resistant and high-temperature nickel alloys, cobalt and zirconium alloys as well as high-alloyed special stainless steels. These materials are used in the chemical process industry, the oil and gas industry, aerospace, automotive and electronics / electrical engineering. VDM Metals operates production sites in Germany (Altena, Siegen, Unna and Werdohl) and the United States (Florham Park, NJ, and Reno, NV). The company employs about 2,000 people worldwide.
History
The original Vereinigte Deutsche Metallwerke AG (VDM) was founded in 1930 by the takeover of Heddernheimer Kupferwerk and Süddeutsche Kabelwerk AG in Frankfurt by Berg-Heckmann-Selve AG in Altena. The merger took place on the initiative of Metallgesellschaft, which was the main shareholder of Heddernheimer Kupferwerke since 1893 and also took over the majority of the new corporate group. The global economic crisis had forced a consolidation of previously competing companies.
The new company had a share capital of 30 million Reichsmark and had branches and manufacturing facilities in Heddernheim, Gustavsburg, Mannheim, Nuremberg, Cologne and in Altena, Werdohl and Duisburg. The group's companies remained independent under their previous name (e. g. Heddernheimer Kupferwerk GmbH), but the production program was redistributed by material group to the individual plants. In March 1934, VDM moved its headquarters to Frankfurt am Main. The incipient rearmament of the Wehrmacht skyrocketed the demand for light metal products. By 1939, the number of employees at VDM rose to 21,000, mainly due to the production of variable pitch propellers for aircraft of the Luftwaffe.
After 1945
Because of the great importance of the VDM for the war economy, almost all buildings and factories were heavily destroyed in the air raids on Frankfurt am Main during the Second World War. At the end of the war, the production collapsed completely, all works were shut down at the direction of the Allies and partly dismantled. It was not until 1946, under the leadership of Wilhelm Kirmser, that the gradual reconstruction and transition to civilian production began.
In the early 1950s, VDM became the world's largest manufacturer and distributor of raw, semi-finished and finished non-ferrous metals and alloys. The upswing reached its peak in the financial year 1960/61. Thereafter, the company continuously lost market share.
The crisis years after 1966
Already for 1966/67 no dividend could be paid to shareholders. A major cause of the difficulties was the fragmented corporate structure of six separate companies, which did not allow a consistent strategy and investment.
In 1969, the plant in Cologne was shut down and the remaining works were combined into seven business units:
Copper and copper alloys
Conducting materials
Prefabricated parts
Nickel and special materials
Light metal
Plastics processing
Packaging solutions
Despite the restructuring and some acquisitions in the 1970s, sales continued to decline. The company reacted with rationalization measures, a reorientation of the production strategy, the sale of individual company shares and the closure of unprofitable production units and plants. This reduced the number of employees from 14,200 (1970) to 6,700 in 1979. After a dramatic deterioration of the results in the financial year 1980/81, the parent plant in Frankfurt-Heddernheim was closed after 129 years on 31 March 1982.
At this point in time, only the plants of the business area nickel (Altena, Unna and Werdohl) were still productive. In the following years, VDM gradually separated from all remaining production facilities and changed its name to MG Vermögensverwaltung AG in 1988.
Post-1988 history
In 1988 the German steelmaker Krupp took over one third, one year later 100 percent of the shares in the VDM Nickel Technologie AG. This division was formed from the merger of the Werdohl and Altena plants into the business area nickel in 1974. In the following years Krupp VDM - as the company was called - initially took over Precision Rolled Products (PRP) with production sites in New Jersey and Nevada and, on 1 October 2009, the activities of the sister company ThyssenKrupp Titanium. From then on, VDM became part of the ThyssenKrupp stainless steel division and operated under the name ThyssenKrupp VDM until 2012.
Outokumpu interlude
Following the sale of the stainless steel division of ThyssenKrupp to Outokumpu in December 2012, VDM temporarily traded under the name Outokumpu VDM. At the end of November 2013 it was announced that VDM would be re-integrated into the ThyssenKrupp Group. Since 1 March 2014, VDM had once again been part of the ThyssenKrupp Group and has since been trading under the independent name of VDM Metals.
Goldberg years
In April 2015, ThyssenKrupp announced the sale of the VDM Group to the financial investor Lindsay Goldberg. On 1 August 2015, the sale was completed.
Acerinox ownership
In November 2019, the Spanish stainless steel producer Acerinox announced the signing of a share-purchase-agreement to acquire VDM Metals. After approval through the competent antitrust authorities the deal was closed in March 2020.
Inventions and material developments
Alloy C-264
Alloy C-264 is a superalloy developed by VDM Metals and launched in 2018. In addition to the alloying element nickel, the alloy contains 25 percent chromium, 20 percent cobalt, about 5.5 percent molybdenum. 1.1 percent aluminum, and 1.7 percent titanium. Various tests have shown that the material in the solution-annealed and hardened condition achieves higher hardness values and lower creep rates than, for example, Alloy C-263 (material number 2.4650, UNS N07263). The application temperature is up to .
Alloy 699 XA
In June 2018, a nickel base alloy with 29 percent chromium and 2 percent aluminum was introduced, which is characterized in particular by its metal dusting resistance. The material has the material number 2.4842 or UNS N06699.
References
German companies established in 1930
Thyssen AG
nickel alloys
superalloys | VDM Metals | [
"Chemistry"
] | 1,348 | [
"Nickel alloys",
"Superalloys",
"Alloys"
] |
61,346,315 | https://en.wikipedia.org/wiki/Shanhui%20Fan | Shanhui Fan (; born 1972) is a Chinese-born American electrical engineer and physicist, with a focus on theoretical, computational and numerical aspects of photonics and electromagnetism. He is a professor of electrical engineering, and a professor of applied physics (by courtesy) at Stanford University. He is the director of the Edward L. Ginzton Lab and Senior Fellow at the Precourt Institute for Energy.
Education
Fan did his undergraduate study in physics from the University of Science and Technology of China from 1988 to 1992. He completed his PhD in Electrical Engineering from Massachusetts Institute of Technology (MIT) in 1997, after which he continued as a postdoctoral researcher in the same group at MIT. His advisor was John D. Joannopoulos.
Career
Fan joined Stanford's faculty of electrical engineering in April 2001.
In 2012, he was a Visiting professor of physics at University of Sydney.
Since 2014, Fan has been the Director of the Edward L. Ginzton Lab. He was appointed Senior Fellow at the Precourt Institute for Energy and courtesy professor of Applied Physics through January 31, 2021.
Fan's research areas include nanophotonics, photonic crystals, metamaterials, topological photonics, plasmonics, solar cells.
, Fan has been granted approximately 57 patents.
Selected works
Coupled Mode Theory For Optical Resonances:
Modulation Induced Non-Reciprocity:
Daytime Radiative Cooling:
Awards and honors
R. W. Wood Prize, Optica (2022), "For foundational discoveries in photonics, ranging from resonator, topological, and non-reciprocal photonics to energy applications including the discovery of daytime radiative cooling based on a new kind of energy source."
Vannevar Bush Faculty Fellowship (2017)
Thomson Reuters Highly Cited Researcher in Physics (2015–)
Fellow, IEEE (2010), for “contributions to nanophotonics”.
Fellow, SPIE (2010)
Fellow, the American Physical Society (2008), for “contributions to the theory and applications of nanophotonic structures and devices, including photonic crystals, plasmonics and meta-materials.
Fellow, the Optical Society of America (2008), “For many deep and creative contributions to physics, analysis, and novel devices in semiconductor, dielectric and metallic optical nanostructures”.
The Adolph Lomb Medal from the Optical Society of America (2007), “For fundamental work in nano-photonic structures”.
The William O. Baker Award for Initiatives in Research (previously the NAS Award for Initiatives in Research) (2007), “For innovative research on the theory and applications of photonic crystal devices”.
David and Lucile Packard Foundation Fellowship for Science and Engineering (2003)
National Science Foundation Faculty Early Career Development Award (2002)
References
External links
Google Scholar, Shanhui Fan
Shanhui Fan Profile at Stanford University
1972 births
Living people
American electrical engineers
Chinese electrical engineers
Chinese emigrants to the United States
Educators from Henan
Engineers from Henan
Fellows of the IEEE
Fellows of SPIE
Fellows of Optica (society)
Fellows of the American Physical Society
MIT School of Engineering alumni
Metamaterials scientists
American optical engineers
People from Zhengzhou
Stanford University Department of Electrical Engineering faculty
University of Science and Technology of China alumni | Shanhui Fan | [
"Materials_science"
] | 660 | [
"Metamaterials scientists",
"Metamaterials"
] |
61,346,523 | https://en.wikipedia.org/wiki/Polifora | Polifora is a type of the multi-light window. It appears in towers and belfries on top floors, where it is necessary to lighten the structure with wider openings. The term polifora usually refers to the window with at least five parts.
Overview
The polifora is a multiple-part window, divided by small columns or pilasters. Each part has a small arch, which can be round or, more often, pointed. Central parts may sometimes be taller than side openings. The space among the arches is often decorated or perforated. The polifora is typical for Gothic architecture and widely used to decorate large cathedrals in the Northern Europe—particularly in Belgium and the Netherlands where the polifora became a true feature of distinction and personalization of the French Gothic style. The polifora is also widely used in Venetian Gothic architecture to decorate the main halls of Venetian palaces.
Such windows can sometimes take specific names that indicate the exact number of openings: pentafora (five parts) and hexafora (six parts) are the most common. Rarer are the windows with higher number of openings; for example the eight-part polifora of the Ca 'Foscari in Venice.
Gallery
See also
Monofora
Bifora
Trifora
Quadrifora
Glossary of architecture
References
Architectural elements
Windows | Polifora | [
"Technology",
"Engineering"
] | 277 | [
"Building engineering",
"Architectural elements",
"Components",
"Architecture"
] |
61,346,683 | https://en.wikipedia.org/wiki/Journal%20of%20Geodesy | The Journal of Geodesy is an academic journal about geodesy published by Springer on behalf of the International Association of Geodesy (IAG). It is the merger and continuation of Bulletin Géodésique and manuscripta geodaetica (both published 1976–1995).
This journal has an impact factor of 4.528 (2018).
References
External links
Journal of Geodesy - Springer
Earth and atmospheric sciences journals
Academic journals associated with international learned and professional societies
Springer Science+Business Media academic journals
Geodesy | Journal of Geodesy | [
"Mathematics"
] | 108 | [
"Applied mathematics",
"Geodesy"
] |
61,347,231 | https://en.wikipedia.org/wiki/List%20of%20mathematician-politicians | Historians of mathematics have noted the involvement of prominent mathematicians in politics at various times and places, notably in Italy during the period of unification at the end of the nineteenth century.
Those who become legislators attempt to use their mathematical skills to legitimise their political positions. However, some parliamentary colleagues tend to view them as failing to connect with the real world.
A maths columnist for Forbes suggested in 2018 that mathematicians in politics would contribute strengths including problem-solving, creativity, overcoming challenges, and collaboration.
John Derbyshire observed in 2003 that mathematicians have no dominant tendency; for example, Cauchy was a reactionary whereas Galois was a radical. He opines that the most influential research mathematicians do not give much thought to politics.
Notable mathematician-politicians
This is a list of people who at some points in their lives achieved notability both as academically trained mathematicians (with a graduate degree, or published in mathematical journals) and also as elected politicians (at a state or national level).
Tadatoshi Akiba (born 1942), member of parliament and mayor of Hiroshima in Japan
Kazimierz Bartel (1882–1941), prime minister and senator in Poland
Muhammad Baydoun (1952–2022), member of parliament and government minister in Lebanon
Vaclav Benda (1946–1999), senator in the Czech Republic
Alberto Beneduce (1877–1944), member of the Italian Reformist Socialist Party and minister of labour and social security
Boris Berezovsky (1946–2013), member of the security council and parliament of Russia
Daniel Biss (born 1977), member of the Illinois Senate and mayor of Evanston, Illinois in the United States
Émile Borel (1871–1956), member of parliament and government minister in France
Francesco Brioschi (1824–1897), member of parliament in Italy
Rudranath Capildeo (1920–1970), member of parliament in Trinidad and Tobago
Lazare Carnot (1753–1823), member of parliament and government in France
Ahmed Chalabi (1944–2015), member of parliament and government in Iraq
Marquis de Condorcet (1743–1794), member of parliament in France
Luigi Cremona (1830–1903), senator and government minister in Italy
Ulisse Dini (1845–1918), member of parliament in |Italy
Charles Dupin (1784–1873), government minister and senator in France
Sergio Fajardo (born 1956), department governor in Colombia
Ute Finckh-Krämer (born 1956), member of parliament in Germany
Taj Haider (born 1942), senator in Pakistan
Daniel Hershkowitz (born 1953), member of the Knesset and government minister in Israel
Reinhard Höppner (1948–2014), minister-president of Saxony-Anhalt in Germany
Eri Jabotinsky (1910–1969), member of the Knesset in Israel
Hermine Agavni Kalustyan (1914–1989), member of parliament in Turkey
Alexander Lubotzky (born 1956), member of the Knesset in Israel
Jerry McNerney (born 1951), congressman in the United States
Michael Meister (born 1961), member of parliament in Germany
Luigi Federico Menabrea (1809–1896), prime minister of Italy
Keith Mitchell (born 1946), prime minister of Grenada
Gaspard Monge (1746–1818), government minister in France
Mohammad-Ali Najafi (born 1952), minister of education in Iran and mayor of Tehran
Chike Obi (1921–2008), member of parliament in Nigeria
Paul Painlevé (1863–1933), prime minister of France
Frederick Pollock (1783-1870), member of parliament in the United Kingdom
Hugo Relander (1865–1947), minister of finance in Finland
Walter Romberg (1928–2014), minister in East Germany's only democratically elected government
George Saitoti (1945–2012), vice-president of Kenya
Blagovest Sendov (1932–2020), chairman of the national assembly of Bulgaria
Frank Terpe (1929–2013), minister in East Germany's only democratically elected government
Faustin-Archange Touadéra (born 1957), prime minister and president of the Central African Republic
Cédric Villani (born 1973), deputy in France
References
Lists of politicians
Politicians
Lists of people by second occupation | List of mathematician-politicians | [
"Technology"
] | 887 | [
"Lists of people in STEM fields",
"Lists of mathematicians"
] |
61,347,379 | https://en.wikipedia.org/wiki/Reiwa%20Shinsengumi | is a progressive and left-wing populist political party in Japan founded by actor-turned-politician Taro Yamamoto in April 2019. The party was formed by left-wing members of the Liberal Party who opposed its merger with the Democratic Party for the People. The party won more than 4% of the vote after contesting the House of Councilors election in July 2019, gaining two seats only about three and a half months after the formation of the party.
History
Founding
Taro Yamamoto, a member of the House of Councillors for Tokyo, founded the party on 1 April 2019. This was with the intent of standing multiple candidates, including himself, in the upcoming House of Councillors election later in the year. On 10 April, Yamamoto held a press conference and announced the party's platform.
2019 House of Councillors election
The party stood multiple candidates in the 2019 House of Councillors election. The party won 2.2 million votes in the national PR block, exceeding the 2% threshold needed to be recognised as a political party, and securing two seats. Nearly one million votes were cast for Yamamoto personally; however, because the party had nominated Yasuhiko Funago and Eiko Kimura, both of whom have disabilities, ahead of him in the party list, Yamamoto did not win a seat. The National Diet Building was adapted to allow barrier-free access for wheelchair users.
Notable party members include university professor Ayumi Yasutomi and former deputy representative of the North Korean abduction liaison Toru Hasuike.
2020 Tokyo gubernatorial election
Yamamoto was one of the 22 candidates participating in the 2020 Tokyo gubernatorial election, coming in third place with 10.72% of the votes. The party promises included a direct cash handout programme due to the COVID-19 pandemic.
2021 Japanese general election
Yamamoto joined with the leaders of the Constitutional Democratic Party, Japanese Communist Party, and Social Democratic Party in running a joint opposition coalition based on common policy goals. Yamamoto, who had been formerly running in Tokyo's 8th district, withdrew to run in the Tokyo PR block to avoid vote splitting against the CDP's Harumi Yoshida. The withdrawal came following pushback from local residents, who were hesitant to vote for Yamamoto, a "parachute candidate," over Yoshida, who had been active within the community for many years prior. The party further withdrew 7 candidates as part of the joint platform to avoid vote splitting between the opposition parties, accounting for 40% of Reiwa Shinsengumi's planned slate of candidates.
There are 20 other candidates besides Yamamoto, running under the Reiwa Shinsengumi banner. One of them is Takashi Takai, who was expelled from the Constitutional Democratic Party of Japan after ignoring COVID-19 state of emergency laws. Takai is Reiwa Shinsengumi's only sitting legislator, formerly elected on the CDP list for the Chūgoku proportional representation block. Takai will be running at Shiga Prefecture's 3rd District.
2022 House of Councillors election
Yamamoto announced his resignation from the House of Representatives seat to which he was elected in 2021 general election, and contested in Tokyo metropolitan constituency for the House of Councillors. Reiwa gained three seats in the election: Yamamoto winning a seat in Tokyo, along with two other candidates who took up seats in the nationwide proportional representation block.
Ideology and policies
Reiwa Shinsengumi has been described as progressive, left-wing populist, and sits on the left of the left–right political spectrum. Some scholars classify the party's views as radical left-wing. Eder-Ramsauer and Matsutani describe Reiwa Shinsengumi as an eclectic left-wing populist party that blends emancipatory radical democratic politics with an openness to communitarian ideas whilst opposing neoliberalism. On the other hand, Axel Klein, who takes an ideational approach, writes that the party does not meet the criteria that define (left) populism.
The party is variously described as being anti-austerity, anti-establishment, and anti-nuclear power as well as supporting animal welfare, minority rights, and economic interventionism. The party is sometimes considered a "liberal-populist" party, and the main supporters of this party are also left-liberals.
In a press conference held shortly after the founding of the party in 2019, Yamamoto announced that his party would push for the abolition of the consumption tax and instead, make the corporation tax a progressive tax and increase government bonds. In addition, he said that the party is against the construction of the Henoko base. In 2019, the party also said it would: ban nuclear power entirely, raise the minimum wage to per hour with public guarantee, implement laws protecting free education, disability rights, LGBT rights, animal rights, institute a basic income of ¥30,000 (circa $283 as of September 2020) per person per month whenever inflation is below 2% (benefits would end whenever inflation is not below the threshold and resume if it goes below again), and reinforce social services.
The party has announced that it would reverse/abolish many of the laws that were revised or passed by Prime Minister Shinzō Abe if elected, including the pre-emptive anti-terrorism law such as martial law State Secrecy Law and the 2015 Japanese military legislation.
Leader
Election results
House of Representatives
House of Councillors
Tokyo gubernatorial
Tokyo prefectural
Notes
References
2019 establishments in Japan
Political parties established in 2019
Political parties in Japan
Animal welfare organizations based in Japan
Anti-nuclear organizations
Disability organizations based in Japan
Disability rights organizations
Economic progressivism
Left-wing parties in Asia
Left-wing populism
LGBTQ political advocacy groups in Japan
Liberal parties in Japan
Progressive parties
Progressive parties in Japan
Populism in Japan
Social liberal parties
Political parties supporting universal basic income | Reiwa Shinsengumi | [
"Engineering"
] | 1,177 | [
"Nuclear organizations",
"Anti-nuclear organizations"
] |
61,347,778 | https://en.wikipedia.org/wiki/Anne%20Bennett%20Prize | The Anne Bennett Prize and Senior Anne Bennett Prize are awards given by the London Mathematical Society.
In every third year, the society offers the Senior Anne Bennett prize to a mathematician normally based in the United Kingdom for work in, influence on or service to mathematics, particularly in relation to advancing the careers of women in mathematics.
In the two years out of three in which the Senior Anne Bennett Prize is not awarded, the society offers the Anne Bennett Prize to a mathematician within ten years of their doctorate for work in and influence on mathematics, particularly acting as an inspiration for women mathematicians.
Both prizes are awarded in memory of Anne Bennett, an administrator for the London Mathematical Society who died in 2012.
The Anne Bennett Prizes should be distinguished from the Anne Bennett Memorial Award for Distinguished Service of the Royal Society of Chemistry, for which Anne Bennett also worked.
Winners
The winners of the Anne Bennett Prize have been:
2015 Apala Majumdar, in recognition of her outstanding contributions to the mathematics of liquid crystals and to the liquid crystal community.
2016 Julia Wolf, in recognition of her outstanding contributions to additive number theory, combinatorics and harmonic analysis and to the mathematical community.
2018 Lotte Hollands, in recognition of her outstanding research at the interface between quantum theory and geometry and of her leadership in mathematical outreach activities.
2019 Eva-Maria Graefe, in recognition of her outstanding research in quantum theory and the inspirational role she has played among female students and early career researchers in mathematics and physics.
2021 Viveka Erlandsson, "for her outstanding achievements in geometry and topology and her inspirational active role in promoting women mathematicians".
2022 Asma Hassannezhad, in recognition of her "work in spectral geometry and her substantial contributions toward the advancement of women in mathematics".
2024 Ana Ros Camacho, "for her ground-breaking work on categorical proofs of the Landau–Ginzburg/Conformal Field Theory correspondence and her tireless dedication to the advancement of women in mathematical physics"
The winners of the Senior Anne Bennett Prize have been:
2014 Caroline Series, in recognition of her leading contributions to hyperbolic geometry and symbolic dynamics, and of the major impact of her numerous initiatives towards the advancement of women in mathematics.
2017 Alison Etheridge, in recognition of her outstanding research on measure-valued stochastic processes and applications to population biology; and for her impressive leadership and service to the profession.
2020 Peter Clarkson, "in recognition of his tireless work to support gender equality in UK mathematics, and particularly for his leadership in developing good practice among departments of mathematical sciences".
2023 Eugénie Hunsicker, "for her outstanding work to improve equality and diversity in the mathematical community and for the depth of her mathematical achievements across an impressive range of areas, from L2 Hodge theory to data science."
See also
List of mathematics awards
References
Awards of the London Mathematical Society
Women in mathematics
Science awards honoring women | Anne Bennett Prize | [
"Technology"
] | 590 | [
"Science and technology awards",
"Women in science and technology",
"Science awards honoring women",
"Women in mathematics"
] |
61,348,137 | https://en.wikipedia.org/wiki/Gamma-ray%20burst%20precursor | A gamma-ray precursor is a short X-ray outburst event that comes before the main outburst of the gamma-ray burst progenitor. There is no consensus on the mechanism for this event, although several theories have been suggested.
History
The first gamma-ray precursor event was from GRB 900126, a long GRB. Immediately, because of the non-thermal nature of the emission, it was recognized that the mechanism of emission for this event was likely internal to the neutron star and not from the accretion disk. Systematic surveys were subsequently carried out to find the percentages of gamma-ray bursts that contained precursor events. Although it was found that 3% of bursts in the BATSE catalogue had a precursor event, a later review found that 20% of long GRBs have a precursor event, although slightly different search criteria were used in that review. That percentage was also found in another study, although others have also found percentages wavering around 10%.
Properties
The precursor event occurs in a wide range of time frames before the main burst. This time can range up to hundreds of seconds. The precursors typically, but not always, show a non-thermal spectrum. Notably, the first gamma-ray precursor to be detected showed a thermal spectrum, with a peak in the X-ray wavelengths. There is no set definition of a precursor. Some allow a broad definition, where the precursor is merely a less-energetic event that happens before the main burst, while some impose additional restrictions, such as the precursor having a longer duration than the actual burst. This is the main reason varying percentages of precursors in samples have been found.
Model
No consensus model exists for gamma-ray burst precursors. According to the collapsar model, a long-GRB results from the collision of jets with the material surrounding a collapsed star. In this model, the precursor could be generated from the jet becomes optically thin. Under this theory, it is difficult to explain the large time gap (hundreds of seconds in some cases) between the precursor and the gamma-ray burst. Various mechanisms for precursors being completely separate phenomena from the main GRB event have also been proposed. In one such scenario, the precursor occurs from the formation of a weak jet during the collapse of the progenitor. This theory explains the time gap between the precursor and burst, although no experimental evidence has differentiated it from others.
References
Gamma-ray bursts
Gamma-ray astronomy | Gamma-ray burst precursor | [
"Physics",
"Astronomy"
] | 500 | [
"Gamma-ray astronomy",
"Physical phenomena",
"Astronomical events",
"Gamma-ray bursts",
"Stellar phenomena",
"Astronomical sub-disciplines"
] |
61,348,732 | https://en.wikipedia.org/wiki/Felecia%20M.%20Nave | Felecia Diane McInnis Nave is an American chemical engineer and academic administrator. She is the 20th president of Alcorn State University and the first female to serve in the position.
Early life and education
Nave is a native of Prentiss, Mississippi. She earned a Bachelor of Science in chemistry from Alcorn State University, graduating cum laude in 1996. She earned a Master of Science in chemical and environmental engineering from University of Toledo. Nave also completed a PhD in engineering at the University of Toledo in 2005. Her dissertation was titled Impact of Mobile Phase Parameters on the Transport Properties of Proteins in Immobilized Metal Affinity Hydrogel Membranes. Maria R. Coleman was her doctoral advisor.
Career
Nave served on the faculty and served in administrative roles at Prairie View A&M University from 2003 to 2018. As provost at PVAMU, she guided the university's expansion both globally and locally. Nave spearheaded projects that involved new degree development, faculty and student development, diversity and inclusion, intensification of PVAMU's research efforts and strengthening the university's focus on STEM fields.
Nave was the provost and vice chancellor of academic affairs at North Carolina Central University. On July 1, 2019, Nave succeeded Alfred Rankins as president of Alcorn State University. Her formal inauguration occurred on April 16, 2021. Nave is the 20th president and first woman to serve in the role.
Personal life
Nave and her husband, Tracie Nave, have four children.
Awards and honors
In 2008, Nave won Prairie View A&M University College of Engineering Outstanding Service Award. In the same year, she was also invited to the Louis Stokes Council of Opportunity in Education Policy Summit at Washington DC. In 2009, Nave received the Prairie View A&M University Student Organization Advisor of the Year. She was also nominated for the National Society of Women Engineers Faculty Advisor Award. In 2013, she was selected as Diverse Issues Emerging Scholars Under 40. In 2015, Nave was the recipient of Top 30 Influential Women of Houston Award. She received the AICHE MAC Eminent Scholars Award in 2017, and University of Toledo Department of Chemical Engineering Outstanding Alumna Award in 2019.
See also
List of women presidents or chancellors of co-ed colleges and universities
References
External links
Living people
Year of birth missing (living people)
People from Jefferson Davis County, Mississippi
Scientists from Mississippi
Engineers from Mississippi
Chemical engineering academics
Alcorn State University faculty
Alcorn State University alumni
University of Toledo alumni
Prairie View A&M University people
North Carolina Central University faculty
African-American chemists
African-American women engineers
21st-century American women engineers
21st-century American engineers
African-American engineers
American chemical engineers
Women chemical engineers
20th-century American chemists
21st-century American chemists
20th-century American women engineers
20th-century American women scientists
Heads of universities and colleges in the United States
Women heads of universities and colleges
American academic administrators
African-American women academics
American women academics
20th-century African-American academics
20th-century American academics
21st-century African-American academics
21st-century American academics
20th-century African-American women
20th-century African-American scientists
21st-century African-American women
21st-century African-American scientists
Chemists from Mississippi
African-American women scientists | Felecia M. Nave | [
"Chemistry"
] | 652 | [
"Chemical engineering academics",
"Chemical engineers"
] |
61,349,287 | https://en.wikipedia.org/wiki/Limepit | A limepit is either a place where limestone is quarried, or a man-made pit used to burn lime stones in the same way that modern-day kilns and furnaces constructed of brick are now used above ground for the calcination of limestone (calcium carbonate, CaCO3) and by which quicklime (calcium oxide, CaO) is produced, an essential component in waterproofing and in wall plastering (plaster skim).
Primitive limepits
The production of lime in the Land of Israel has been dated as far back as the Canaanite period, and has continued in successive generations ever since. The man-made limepit was usually dug in ground near the place where limestone could be quarried. Remnants of old limepits have been unearthed in archaeological digs all throughout the Levant. In a country where hundreds of such limepits or limekilns for burning limestone were found, the Israel Antiquities Authority (IAA) describes dozens of them (), one discovered in Kiryat Ye'arim, another in Har Giora - East (2 km. north of Bar-Giora), as well as in Neve Yaakov, among other places. Two lime kilns, stratigraphically dated to the late Hellenistic period were excavated at Ramat Rachel, the latter of which being circular in shape (3.6 metres in diameter) and built into the ruins of a large pool, using earlier walls. A rounded kiln (2.5–2.8 metres in diameter) was found northeast of Jerusalem dating back to the Iron Age (seventh–sixth century BCE), and was built of stones and had a rectangular unit adjacent to it. In the Lachish area, several lime kilns were excavated by a team on behalf of the IAA, and which kilns were partially hewn in the bedrock and partially built of fieldstones, and last used at some point between the mid-15th century and the mid-17th century CE.
In Bedouin-Arab culture in Israel, the limepit was dug to a depth of about and about in diameter.
By all appearances, the pit was made after the same basic principle used in a "Dakota fire pit," which is made with an air inlet at the base, allowing for air-ventilation, but on a larger scale. Air intake was achieved by digging an adjacent channel which ran from a short distance into the limepit, or else an underground shaft (shafts) at floor level of limepit leading from an open area, allowing for a steady, free-flowing draught of air to be drawn into the limepit as it burns. In this way, there was no need for the use of bellows to reach a high temperature, but only to stoke the fire with wood continuously for several days for it to reach a temperature of 900° Celsius (1650° F). Its mode of operation was similar to that of a shaft kiln. After cooling, wood ashes that had accumulated were then separated from the burnt blocks of limestone. The limestone blocks were then crushed, afterwards slaked (the process of adding water and constantly turning the lime to create a chemical reaction, whereby the burnt lime, or what is known also as calcium oxide, is changed into calcium hydroxide), and mixed with an aggregate to form an adhesive paste (plaster) used in construction and for daubing buildings.
When properly burnt, limestone loses its carbonic acid () and becomes converted into caustic or quicklime (CaO). One-hundred parts of raw limestone yields about 56 parts of quicklime. In the West, quicklime was formerly a major component in common mortar, besides its predominant use in plastering. In some Middle-Eastern countries where rain-fall was scarce in the dry season, lime production for use in plastering home-made cisterns (in making them impermeable by adding thereto a pozzolanic agent) was especially important. This enabled them to collect the winter run-off of rain water and to have it stored for later use, whether for personal or agricultural needs. Lime is also an important component in the production of Nabulsi soap, in dyeing fabrics, and in use as a depilatory.
Basic design
Many limepits were sunken in the ground at a depth of between 2.5 and 5 meters and 3 to 4.5 meters in diameter, in a circular fashion, and some were built with a retaining wall along the inside for support, usually constructed of uncut field-stones. Simpler limepits were made without supportive walls. In the following account, Abu-Rabiʻa describes the practice of Bedouins in the Negev, during the late 19th and early 20th-century:
Lime is derived from chalk by burning. The Bedouins used it in plastering their cisterns. Burning chalk stone was performed in simple kilns in close proximity to where the chalk was found. Lime kilns were made by digging a round hole, three metres wide, two and a half metres deep. After the hole was dug, the chalk and fuel for a fire would be brought to it. Stones of chalk (limestone) would be arranged in a circular dome in the pit. The burning process would last three to six days, without letup. After the burning was finished, the kiln would be left to cool for four to six days. The lime would then be taken out. The large lime blocks along the edge of the pit were considered of the highest quality, while the small pieces towards the center of the pit were considered grade B. One camel load, or cantur (qentar / quntar = 100 ratels, or 250–300 kilograms), of lime would fetch 40 grush on the Jerusalem market in the early 1880s.
In Israel, the principal fuel used to keep the lime-kiln burning was the dried brushwood of prickly burnet (Sarcopoterium spinosum) and savory (Satureja thymbra), where often camel loads of this dried wood would be hauled to the lime-kiln. Monolithic stone structures were already in use for burning limestone (nāri) during the Ottoman period, throughout the Levant. Modern kilns for burning lime first appeared in Palestine during the British Mandate.
Chemical changes
The lime stones selected were those that had the least amount of impurities within them. Limepits were almost always built near the supply of limestone, and a sufficient pile of wood kindling was heaped in great store before the actual burning process began, a supply that was to last between 3 and 7 days of continual burning, both, by night and day. In the southern Mediterranean regions, one of the favorite wood sources was thorny burnet (Sarcopoterium spinosum). The fire was attended by men with long staves and pitchforks who pushed the burning material into the pit. Initially, a cloud of smoke billowed from the pit. After several days of burning, when the uppermost stone in the fire pit began to glow a fiery red, it signaled that the burning process of the lime was finished, and that the process of carbon dioxide emissions from the limestone has been completed, and that the lime was now ready for marketing as lime or powder. After being allowed to cool, the burnt limestone was extracted from the pit when it was light and brittle. During the burning process, the limestone loses about 50% of its original anatomical weight. The lime becomes ready for use only after water has been added.
Gallery
See also
Lime kiln
Lime plaster
Qadad (Method of waterproofing cisterns in South Arabia)
References
Bibliography
Eliyahu-Behar, A.; Yahalom-Mack, N.; Ben-Shlomo, D. (2017). "Excavation and Analysis of an Early Iron Age Lime Kiln", Israel Exploration Journal 67, pp. 14–31
Kilns
History of chemistry
Soil-based building materials
Lime kilns
Construction in Asia
Fireplaces
Building materials
Plastering
Firing techniques | Limepit | [
"Physics",
"Chemistry",
"Engineering"
] | 1,672 | [
"Building engineering",
"Chemical equipment",
"Coatings",
"Architecture",
"Construction",
"Lime kilns",
"Materials",
"Kilns",
"Plastering",
"Matter",
"Building materials"
] |
61,349,807 | https://en.wikipedia.org/wiki/Mollisquama%20mississippiensis | Mollisquama mississippiensis or the American pocket shark is a species of pocket shark native to the Gulf of Mexico. It is the second species of pocket shark to be described.
Discovery
The shark was first discovered by scientists from Tulane University that were conducting a study on sperm whales in 2010. In 2013, the National Oceanic and Atmospheric Administration identified it as a pocket shark, the first to be found in its region. A previously found specimen of a different pocket shark species was caught off the coast of Chile in 1979 and was used to identify the two different species due to their differences in size, vertebrae and numerous light-producing photophores.
Description
The head is bulbous, resembling that of a whale. The shark is very small, at only . Near the gills are two "pockets" that secrete a luminous fluid which may enable the shark to hunt. The body is grey with the fins being darker. The areas around the gills are cream colored. There are clusters of photophores around the body, which are able to produce light.
References
Fish described in 2019
Fish of the Gulf of Mexico
Dalatiidae
Species known from a single specimen | Mollisquama mississippiensis | [
"Biology"
] | 231 | [
"Individual organisms",
"Species known from a single specimen"
] |
61,349,865 | https://en.wikipedia.org/wiki/Ship%20and%20Ocean%20Industries%20R%26D%20Center | The Ship and Ocean Industries Research and Development Center (SOIC; ) is a Taiwanese government owned naval architecture and maritime research institute founded in 1976.
Overview
The prime mission of SOIC is to support Taiwan’s maritime industry. To further this mission it provides marine engineering planning, ship and ocean platform design, technical services, and knowledge integration services to private and public organizations and companies. SOIC has designed vessels for shipping giants, local industry, the Republic of China Navy, and the Coast Guard Administration.
History
SOIC was founded as United Ship Design and Development Center (USDDC) on 1 July 1976. The first chairman was Chieh-Jen Chiang. The first ship designed by USDDC was a 6,100 DWT log carrier. In 2012 the institute changed its name to Ship and Ocean Industries R&D Center to better communicate the scope of its activities.
In the 21st century SOIC has been involved in projects to advance Taiwan's offshore wind power industry.
Organization
The Yacht Industry Department of SOIC is the only government supported R&D center for yacht materials and design in the world.
Vessels designed
Pan Shi-class fast combat support ship
ROCS Wu Yi (AOE-530)
SOIC designed the Tuo Chiang-class corvette in collaboration with the Taiwanese Ministry of National Defense's Naval Shipbuilding Development Center.
SOIC, along with CSBC Corporation, Taiwan and foreign technical advisors, is involved in the development of Taiwan's Indigenous Defence Submarine.
Hybrid electric ferry in partnership with the Finnish company Visedo OY.
See also
Industrial Technology Research Institute
Automotive Research & Testing Center
Institute for Information Industry
Taiwan Textile Research Institute
References
1976 establishments in Taiwan
Organizations based in New Taipei
Science and technology in Taiwan
Research institutes in Taiwan
Research institutes established in 1976
Yacht design firms
Boat and ship designers
Marine engineering organizations | Ship and Ocean Industries R&D Center | [
"Engineering"
] | 363 | [
"Marine engineering organizations",
"Marine engineering"
] |
61,351,273 | https://en.wikipedia.org/wiki/Monofora | Monofora is a type of the single-light window, usually narrow, crowned by an arch, and decorated by small columns or pilasters.
Overview
The term usually refers to a certain type of window designed during the Romanesque, Gothic, and Renaissance periods, and also during the nineteenth-century Eclecticism in architecture. In other cases, the term may mean an arched window with a single opening.
Gallery
See also
Lancet window
Bifora
Trifora
Quadrifora
Polifora
References
Architectural elements
Windows | Monofora | [
"Technology",
"Engineering"
] | 104 | [
"Building engineering",
"Architectural elements",
"Components",
"Architecture"
] |
61,351,870 | https://en.wikipedia.org/wiki/Phase-field%20models%20on%20graphs | Phase-field models on graphs are a discrete analogue to phase-field models, defined on a graph. They are used in image analysis (for feature identification) and for the segmentation of social networks.
Graph Ginzburg–Landau functional
For a graph with vertices V and edge weights , the graph Ginzburg–Landau functional of a map is given by
where W is a double well potential, for example the quartic potential W(x) = x2(1 − x2). The graph Ginzburg–Landau functional was introduced by Bertozzi and Flenner. In analogy to continuum phase-field models, where regions with u close to 0 or 1 are models for two phases of the material, vertices can be classified into those with uj close to 0 or close to 1, and for small , minimisers of will satisfy that uj is close to 0 or 1 for most nodes, splitting the nodes into two classes.
Graph Allen–Cahn equation
To effectively minimise , a natural approach is by gradient flow (steepest descent). This means to introduce an artificial time parameter and to solve the graph version of the Allen–Cahn equation,
where is the graph Laplacian. The ordinary continuum Allen–Cahn equation and the graph Allen–Cahn equation are natural counterparts, just replacing ordinary calculus by calculus on graphs.
A convergence result for a numerical graph Allen–Cahn scheme has been established by Luo and Bertozzi.
It is also possible to adapt other computational schemes for mean curvature flow, for example schemes involving thresholding like the Merriman–Bence–Osher scheme, to a graph setting, with analogous results.
See also
Graph cuts in computer vision
References
Graph theory
Mathematical modeling | Phase-field models on graphs | [
"Mathematics"
] | 356 | [
"Discrete mathematics",
"Mathematical modeling",
"Applied mathematics",
"Graph theory",
"Combinatorics",
"Mathematical relations"
] |
61,351,935 | https://en.wikipedia.org/wiki/Fluorocarbonate | A carbonate fluoride, fluoride carbonate, fluorocarbonate or fluocarbonate is a double salt containing both carbonate and fluoride. The salts are usually insoluble in water, and can have more than one kind of metal cation to make more complex compounds. Rare-earth fluorocarbonates are particularly important as ore minerals for the light rare-earth elements lanthanum, cerium and neodymium. Bastnäsite is the most important source of these elements. Other artificial compounds are under investigation as non-linear optical materials and for transparency in the ultraviolet, with effects over a dozen times greater than Potassium dideuterium phosphate.
Related to this there are also chlorocarbonates and bromocarbonates. Along with these fluorocarbonates form the larger family of halocarbonates. In turn halocarbonates are a part of mixed anion materials. Compounds where fluorine connects to carbon making acids are unstable, fluoroformic acid decomposes to carbon dioxide and hydrogen fluoride, and trifluoromethyl alcohol also breaks up at room temperature. Trifluoromethoxide compounds exist but react with water to yield carbonyl fluoride.
Structures
The structure of the carbonate fluorides is mainly determined by the carbonate anion, as it is the biggest component. The overall structure depends on the ratio of carbonate to everything else, i.e. number (metals and fluorides)/number of carbonates. For ratios from 1.2 to 1.5 the carbonates are in a flat dense arrangement. From 1.5 to 2.3 the orientation is edge on. From 2.5 to 3.3 the arrangement is flat open. With a ratio from 4 to 11, the carbonate arrangement is flat-lacunar.
The simplest formula is LnCO3F, where Ln has a 3+ charge.
For monocations there is A3CO3F, where A is a large ion such as K, Rb or Tl.
For M = alkali metal, and Ln = lanthanide: MLnCO3F2 1:1:1:2; M3Ln(CO3)2F2 3:1:2:2; M2Ln(CO3)2F 2:1:2:1; M4Ln(CO3)2F3·H2O 4:1:2:3; M4Ln2(CO3)3F4 2:3:3:4. M2Ln(CO3)F2 2:1:1:3.
For B = alkaline earth and Ln = lanthanide (a triple-charged ion) BLn(CO3)2F 1:1:2:1; BLn2(CO3)3F2 1:2:3:2 B2Ln3(CO3)5F3 2:3:5:3; B2Ln(CO3)2F3 2:1:2:3; B2Ln(CO3)F5 2:1:1:5 B2Ln(CO3)3F 2:1:3:1; B3Ln(CO3)F7 3:1:1:7; B3Ln2(CO3)5F2 3:2:5:2.
For alkali with dication combinations: MB: MBCO3F MB3(CO3)2F3·H2O.
For dications A and B there is ABCO3F2 with a degenerate case of A = B.
KPb2(CO3)2F is layered. Each layer is like a sandwich, with lead and carbonate in the outer sublayers, and potassium and fluoride in the inner layer. K2.70Pb5.15(CO3)5F3 extends this structure with some of the layers also being a double-decker sandwich of carbonate, fluoride, carbonate, fluoride, carbonate.
In the rare-earth fluorocarbonates the environment for the rare-earth atoms is 9-coordinated. Six oxygen atoms from carbonate are at the apices of a trigonal prism, and fluoride ions cap the rectangular faces of the prism.
Formation
Carbonate fluoride compounds can be formed by a variety of related methods involving heating the precursor ingredients with or without water. Thallous fluoride carbonate was made simply by evaporating a fluoride thallium solution in ethanol and water in air. It absorbed sufficient carbon dioxide to yield the product. Most other carbonate fluorides are very insoluble and need high-temperature water to crystallise from. Supercritical water heated between 350 and 750 °C under pressures around 200 bars can be used. A sealed platinum tube can withstand the heat and pressure. Crystallisation takes about a day. With subcritical water around 200 °C, crystallisation takes about 2 days. This can happen in a teflon-coated pressure autoclave. The starting ingredients can be rare-earth fluorides and alkali carbonates. The high pressure is needed to keep the water liquid and the carbon dioxide under control, otherwise it would escape. If the fluoride levels are low, hydroxide can substitute for the fluoride. Solid-state reactions require even higher temperatures.
Bastnäsite along with lukechangite (and petersenite) can be precipitated from a mixed solution of CeCl3, NaF, and NaOH with carbon dioxide. Another way to make the simple rare-earth fluorocarbonates is to precipitate a rare-earth carbonate from a nitrate solution with ammonium bicarbonate and then add fluoride ions with hydrofluoric acid (HF).
Pb2(CO3)F2 can be made by boiling a water solution of lead nitrate, sodium fluoride and potassium carbonate in a 2:2:1 molar ratio.
Properties
The visible spectrum of fluorocarbonates is determined mainly by the cations contained. Different structures only have slight effect on the absorption spectrum of rare-earth elements. The visible spectrum of the rare-earth fluorocarbonates is almost entirely due to narrow absorption bands from neodymium. In the near infrared around 1000 nm there are some absorption lines due to samarium and around 1547 nm are some absorption features due to praseodymium. Deeper into the infrared, bastnäsite has carbonate absorption lines at 2243, 2312 and 2324 nm. Parisite only has a very weak carbonate absorption at 2324 nm, and synchysite absorbs at 2337 nm.
The infrared spectrum due to vibration of carbon–oxygen bonds in carbonate is affected by how many kinds of position there are for the carbonate ions.
Reactions
An important chemical reaction used to prepare rare-earth elements from their ores, is to roast concentrated rare-earth fluorocarbonates with sulfuric acid at about 200 °C. This is then leached with water. This process liberates carbon dioxide and hydrofluoric acid and yields rare-earth sulfates:
2 LnCO3F + 3 H2SO4 → Ln2(SO4)3 + 2 HF + 2 H2O + 2 CO2.
Subsequent processing precipitates a double sulfate with sodium sulfate at about 50 °C. The aim is to separate out the rare-earth elements from calcium, aluminium, iron and thorium.
At high enough temperatures the carbonate fluorides lose carbon dioxide, e.g.
KCu(CO3)F → CuO + KF + CO2
at 340 °C.
The processing of bastnäsite is important, as it is the most commonly mined cerium mineral. When heated in air or oxygen at over 500 °C, bastnäsite oxidises and loses volatiles to form ceria (CeO2). Lukechangite also oxidises to ceria and sodium fluoride (NaF). Ce7O12 results when heated to over 1000 °C.
2 Ce(CO3F) + O2 → 2 CeO2 + 2 CO2 + F2
Na3Ce2(CO3F)4F + O2 → 2 CeO2 + 3 CO2 + NaF + Na2CO3
At 1300 °C Na2CO3 loses CO2, and between 1300 and 1600 °C NaF and Na2O boil off.
When other rare-earth carbonate fluorides are heated, they lose carbon dioxide and form an oxyfluoride:
LaCO3F → LaOF + CO2
In some rare-earth extraction processes, the roasted ore is then extracted with hydrochloric acid to dissolve rare earths apart from cerium. Cerium is dissolved if the pH is under 0, and thorium is dissolved if it is under 2.
KCdCO3F when heated yields cadmium oxide (CdO) and potassium fluoride (KF).
When lanthanum fluorocarbonate is heated in a hydrogen sulfide, or carbon disulfide vapour around 500 °C, lanthanum fluorosulfide forms:
LaCO3F + CO2 → LaSF + 1.5 CO2
Note that this also works for other lanthanides apart from cerium.
When lanthanum carbonate fluoride is heated at 1000 °C with alumina, lanthanum aluminate is produced:
LaCO3F + 2 Al2O3 → LaAlO3 + CO2 + equiv AlOF
Within the hot part of the Earth's crust, rare-earth fluorocarbonates should react with apatite to form monazite.
Minerals
Some rare-earth fluorocarbonate minerals exist. They make up most of the economic ores for light rare-earth elements (LREE). These probably result from hydrothermal liquids from granite that contained fluoride. Rare-earth fluorocarbonate minerals can form in bauxite on carbonate rocks, as rare-earth fluoride complexes react with carbonate. Carbonate fluoride compounds of rare-earth elements also occur in carbonatites.
Artificial
These are non-linear optical crystals in the AMCO3F family
KSrCO3F
KCaCO3F
RbSrCO3F
KCdCO3F
CsPbCO3F
RbPbCO3F
RbMgCO3F
KMgCO3F
RbCdCO3F
CsSrCO3F
RbCaCO3F
KZnCO3F
CsCaCO3F
RbZnCO3F
References
Fluorides
Carbonates
Mixed anion compounds
Double salts | Fluorocarbonate | [
"Physics",
"Chemistry"
] | 2,200 | [
"Matter",
"Mixed anion compounds",
"Double salts",
"Salts",
"Fluorides",
"Ions"
] |
61,352,041 | https://en.wikipedia.org/wiki/Plumbing%20%28mathematics%29 | In the mathematical field of geometric topology, among the techniques known as surgery theory, the process of plumbing is a way to create new manifolds out of disk bundles. It was first described by John Milnor and subsequently used extensively in surgery theory to produce manifolds and normal maps with given surgery obstructions.
Definition
Let be a rank n vector bundle over an n-dimensional smooth manifold for i = 1,2. Denote by the total space of the associated (closed) disk bundle and suppose that and are oriented in a compatible way. If we pick two points , i = 1,2, and consider a ball neighbourhood of in , then we get neighbourhoods of the fibre over in . Let and be two diffeomorphisms (either both orientation preserving or reversing). The plumbing of and at and is defined to be the quotient space where is defined by .
The smooth structure on the quotient is defined by "straightening the angles".
Plumbing according to a tree
If the base manifold is an n-sphere , then by iterating this procedure over several vector bundles over one can plumb them together according to a tree§8. If is a tree, we assign to each vertex a vector bundle over and we plumb the corresponding disk bundles together if two vertices are connected by an edge. One has to be careful that neighbourhoods in the total spaces do not overlap.
Milnor manifolds
Let denote the disk bundle associated to the tangent bundle of the 2k-sphere. If we plumb eight copies of according to the diagram , we obtain a 4k-dimensional manifold which certain authors call the Milnor manifold (see also E8 manifold).
For , the boundary is a homotopy sphere which generates , the group of h-cobordism classes of homotopy spheres which bound π-manifolds (see also exotic spheres for more details). Its signature is and there exists V.2.9 a normal map such that the surgery obstruction is , where is a map of degree 1 and is a bundle map from the stable normal bundle of the Milnor manifold to a certain stable vector bundle.
The plumbing theorem
A crucial theorem for the development of surgery theory is the so-called Plumbing Theorem II.1.3 (presented here in the simply connected case):
For all , there exists a 2k-dimensional manifold with boundary and a normal map where is such that is a homotopy equivalence, is a bundle map into the trivial bundle and the surgery obstruction is .
The proof of this theorem makes use of the Milnor manifolds defined above.
References
Differential topology
Surgery theory
Fiber bundles
Vector bundles
Manifolds | Plumbing (mathematics) | [
"Mathematics"
] | 538 | [
"Space (mathematics)",
"Topological spaces",
"Topology",
"Differential topology",
"Manifolds"
] |
69,243,592 | https://en.wikipedia.org/wiki/Mercedes-Benz%20MB503%20engine | The Mercedes-Benz MB 503 was a German prototype four-stroke V-12 gasoline marine and aircraft engine, designed and concepted before World War II. The MB 503 was based on and derived from the Daimler-Benz DB 603 inverted V-12 aircraft engine. It was a liquid-cooled 12-cylinder inverted V12 enlargement of the DB 601, which was in itself a development of the DB 600. The eventual powerplants chosen to be used in the Panzer VIII Maus super-heavy tank were the MB 509 V-12 gasoline engine, derived from the Daimler-Benz DB 603; and also the MB 517 V-12 diesel engine.
See also
Mercedes-Benz MB507 - Diesel variant based on the Daimler-Benz DB 603.
References
Mercedes-Benz engines
Marine engines
Engines by model
Gasoline engines by model
V12 engines | Mercedes-Benz MB503 engine | [
"Technology"
] | 182 | [
"Marine engines",
"Engines",
"Engines by model"
] |
69,244,895 | https://en.wikipedia.org/wiki/Funga | Funga refers to the fungi of a particular region, habitat, or geological period. In life sciences, funga is a recent term (2000s) for the kingdom fungi similar to the longstanding fauna for animals and flora for plants. The term seeks to simplify projects oriented toward implementation of educational and conservation goals. The term highlights parallel terminology referring to treatments of these macroorganisms in particular geographical areas. An official proposal for the term occurred in 2018, despite previous use.
The Species Survival Commission (SSC) of the International Union for Conservation of Nature (IUCN) in August 2021 called for the recognition of fungi as one of three kingdoms of life, and critical to protecting and restoring Earth. Funga was recommended by the IUCN in 2021. They ask that the phrase animals and plants be replaced by animals, fungi, and plants, and fauna and flora by fauna, flora, and funga.
References
Ecology
Fungi
Ecology terminology | Funga | [
"Biology"
] | 188 | [
"Fungus stubs",
"Ecology terminology",
"Fungi",
"Ecology"
] |
69,248,246 | https://en.wikipedia.org/wiki/Identity%20safety%20cues | Identity safety cues are aspects of an environment or setting that signal to members of stigmatized groups that the threat of discrimination is limited within that environment and / or that their social identities are welcomed and valued. Identity safety cues have been shown to reduce the negative impacts impact of social identity threats, which are when people experience situations where they feel devalued on the basis of a social identity (see stereotype threat). Such threats have been shown to undermine performance in academic and work-related contexts and make members of stigmatized groups feel as though they do not belong. Identity safety cues have been proposed as a way of alleviating the negative impact of stereotype threat or other social identity threats, reducing disparities in academic performance for members of stigmatized groups (see achievement gaps in the United States), and reducing health disparities caused by identity related stressors.
Research has shown that identity safety cues targeted towards one specific group can lead individuals with other stigmatized identities to believe their identities will be respected and valued in that environment. Further, the implementation of identity safety cues in existing research did not cause members of non-stigmatized groups feeling threatened or uncomfortable. In fact, some work has suggested that the benefits of identity safety cues extend to members of non-stigmatized groups. For example, implementation of identity safety cues within a university context has been shown to increase student engagement, efficacy, and reduce the average number of student absences for all students, but especially those from stigmatized groups. Several types of identity safety cues have been identified.
Types of cues
Diversity philosophies and programing
There is evidence suggesting that when individuals or organizations communicate that they value diversity highly, concerns about identity threats are reduced. For example, Hall and colleagues tested the impact of communicating gender inclusive policies on self-reported belonging of women working at engineering firms. Across two studies, Hall and colleagues found that when women working at engineering firms were presented with information communicating gender inclusive policies, they reported increased belonging, fewer concerns about experiencing gender stereotyping in the workplace, and expected to have more pleasant conversations with male coworkers.
Within a classroom context, exposure to information stating that instructors or schools hold multicultural philosophies has been shown to increase student agency, self-confidence, and classroom engagement for students from stigmatized groups. Exposure to diversity philosophies and programming can have a lasting effect. In a recent study, Birnbaum and colleagues had first-year college students read a diversity statement that represented the schools’ diversity philosophy as either being in favor of multiculturalism or colorblindness. The students’ academic progress was tracked over the course of the next two years. Students from stigmatized groups who read the multicultural diversity statement had increased academic performance over the course of the two years compared to students who read the colorblind diversity statement. Similarly, a 2021 study found that when university students were presented with information about equity and non-discrimination policies in the classroom, students from stigmatized groups reported greater belonging within the classroom and reported fewer absences than students who were not presented with the same equity and non-discrimination policies. Further, students in this study also reported perceiving the instructor as behaving in a more inclusive manner and reported greater concerns about addressing social inequities when they were presented with information about equity and non-discrimination policies.
However, the evidence for the effectiveness of diversity philosophies and programming alone is mixed. For example, Valarie Purdie-Jones and colleagues ran a study comparing the effects of Black representation within the workplace and organizational claims of valuing diversity on Black professionals’ sense of organizational trust and belonging. Black professionals who were presented with information showing that an organization a higher number of Black employees reported feeling greater organizational trust and belonging. Similarly, organizational claims of valuing diversity led to an increased sense of organizational trust and belonging. However, the type of diversity philosophy communicated influenced how effective the philosophy was at increasing organizational trust and belong. Black professionals who received information stating that the organization held a color-blind philosophy of diversity (i.e., the idea that differences are insignificant and should not be attended to; See Color Blindness) felt lower organizational trust and belonging than Black professionals who received information stating that the organization held a multicultural perspective (i.e., the idea that differences between social groups are meaningful as diverse perspectives offer unique insight and strengths; See Multiculturalism). Similarly, a 2015 study from Wilton and colleagues exposed participants to either a colorblind or multicultural diversity statement and then measured their expectations about anticipated bias and racial and gender diversity. Participants who were exposed to a colorblind diversity statement expected to experience increased levels of bias and expected less racial and gender diversity than participants who were exposed to a multicultural diversity statement.
Minority representation cues
One form of identity safety cues that has shown promise is invoking the real or imagined presence of other members of stigmatized groups as a way of suggesting that ones’ social identity will not be devalued and are safe. The majority of this work has been done amongst racial minorities and women in contexts where they represent a numerical minority (e.g., STEM contexts, in male dominated workplaces). For example, a 2007 study explored the impacts of signaling balanced versus unbalanced gender ratios in STEM on belonging for female and male STEM majors. In this study, women who watch a video that showed a much larger number of men at a STEM conference exhibited greater levels of cognitive and physiological vigilance, reported a lower sense of belonging, and less desire to participate in the conference. However, women who watched a video showing a roughly equal number of men and women at the same STEM conference exhibited less vigilance, reported a heightened sense of belonging, and a greater desire to participate in the conference. Men's vigilance, sense of belonging, and desire to participate in the conference were unaffected by watching either video.
Having a role model with a shared stigmatized identity (e.g., female students having a female professor role model) has also been shown to have similar positive effects. For example, a 2019 study explored the effects of having a Roma or non-Roma role model on Roma children in Slovakia. Presenting Roma children with a known role model from their ethnic group was shown to increase academic achievement and reduce stereotype threat, as opposed to presenting children of role models from different ethnic groups. Similarly, research has found that being exposed to a female role model can help to reduce the identity threat women experience after being exposed to information about the biases women face in STEM.
Even though the majority of this work has been done in STEM contexts, similar work has been done in the context of the workplace. For instance, a 2008 study found that Black professionals who were presented with information showing that an organization had a higher number of Black employees felt a greater sense of trust and belonging in that organization compared to Black professionals who were presented with information showing that an organization had a small number of Black employees. However, for these cues to be effective, they must reasonably reflect the actual percentage of individuals that hold a stigmatized identity within a given context. A 2020 study found that whenever racial and ethnic minorities perceive an organization as falsely inflating the percent of employees that hold a stigmatized identity, racial and ethnic minorities report increased concerns about belonging, performance, and expressing themselves.
Environmental features
Environmental cues are features of an environment that reduce identity threat by communicating inclusive norms and values. Typically, these cues include background objects (e.g., posters, items on a table) or counter-stereotypic imagery (e.g., a rainbow flag in a gym predominantly frequented by heterosexual men and women). Studies exploring the impact of environmental cues on belonging in STEM by members of marginalized groups have found strong evidence for the power of environmental cues to influence one's sense of belonging and concerns about discrimination. For example, a 2009 study found that changing objects in a computer science classroom from objects considered stereotypical of computer science (e.g., Star Trek poster, video games) to non-stereotypical objects (e.g., nature poster, phone books) increased female STEM majors’ sense of belonging and interest in computer science by reducing associations between computer science and masculine stereotypes. In a different domain, the presence of gender-inclusive bathrooms is associated with greater perceived fairness within the workplace, more positive perceptions of workplace climate for women and racial and ethnic minorities, and increased perceptions of the workplace as egalitarian.
The presence of environmental cues has also been associated with differences in academic outcomes as well. For example, a 2013 study randomly assigned male and female students to give a persuasive speech in a virtual-reality classroom that had a photograph of a male world leader, a female world leader, or no photograph. When the room featured either a photograph of a male world leader or no picture, male students gave speeches that were longer and rated as better than the female students’ speeches. However, the presence of female leader photographs increased female students’ speaking time and their speeches were rated as higher quality. In a similar study, American Indian high school students who were randomly assigned to see stereotypic American Indian imagery in a classroom (e.g., Chief Wahoo of the Cleveland Indians) were less likely to mention academic achievement when asked about where they imagined themselves in the future than American Indian students who saw no image or a counter-stereotypic poster of an American Indian woman in front of a microscope.
Identity safe information
Another form of identity safety cues that has shown promise is providing members of stigmatized groups with information that reduces the importance or relevance of negative stereotypes, conveys non-biased expectations, and/or conveys a positive climate for members of stigmatized groups. The majority of this work has been done in academic contexts in order to reduce the impact of stereotype threat. For example, a prominent 1999 study explored if stereotype threat among female students could be reduced by telling the class that prior administrations of the math exam they were about to take had revealed no gender differences in performance. When students were informed that they were taking a “gender fair” math exam, female students performed equally well to male students taking the same exam. However, when female students were told before that the exam had been shown to produce gender differences, female students performed worse than male students. Similarly, telling women that there are no differences in women's and men's leadership abilities has been shown to eliminate gender gaps in leadership aspirations.
However, other studies have found that merely providing identity safe information alone is sometimes not enough to reduce stereotype threat or identity threat. For example, in one study women were presented with a text explaining that stereotypes and not gender differences were responsible for academic performance gaps between men and women and were then asked to complete a math task. It was found that women who were presented with information about stereotype threat and gender differences in academic outcomes performed significantly worse at the math task.
More recently, information about expectations for discrimination (or lack thereof) have also been explored as an identity safety cue. For example, a 2020 study from Murrar and colleagues explored the impact of informing university students that most of their peers endorsed positive diversity related values, cared strongly about inclusion in university classrooms, and typically behaved in a non-discriminatory manner. Being presented with this information caused all students, regardless of their background, to evaluate classroom climate more positively and to report more positive attitudes toward members of stigmatized groups. Further, students from stigmatized groups reported greater sense of belonging and better self-reported physical health. In a similar study, Black women who were informed of the presence of a non-Black female ally reported an increased sense of belonging in the workplace.
Contexts
Education
Much of the research on identity safety cues came from early attempts to mitigate the detrimental effects of stereotype threat. For instance, one of the first studies to use what is now known as an identity safety cue explored the impact of telling female students that there were no gender differences in a math exam (i.e., presenting identity safe information). A large portion of current research on identity safety cues continues to explore ways to reduce educational disparities between members of stigmatized groups and members of stigmatized groups.
Workplace
Another major focus of identity safety cue research is on methods that can successfully increase the belonging and retention of members of stigmatized groups within the workplace. For example, a 2015 study explored the impact of different philosophies of intelligence on female employees expectations to be stereotyped in the workplace and organizational belonging. When a consulting company displayed the belief that intelligence and abilities are malleable on their mission statement or website compared to the belief that intelligence is fixed women trusted the company more and expected to be stereotyped less. However, gender representation within the company did not affect women's trust in the company. Similarly, a 2019 study found that Latina women felt greater trust, belonging, and interest in a fictional STEM company when learning about a Latinx scientist employee than a White scientist (regardless of the gender of the scientist). More recently, a 2021 study explored whether the presence of an employee's pronouns in an employee biography acted as an identity-safety cue for sexual and gender minorities. The inclusion of pronouns resulted in more positive organizational attitudes among gender and sexual minority participants and increased perceptions of coworker allyship, regardless of whether the disclosure of pronouns was required or optional by the organization.
Healthcare
While the majority of research on identity safety cues has been done in either academic or workplace contexts, there has been a recent push to explore the effectiveness of these cues in healthcare contexts to see if they can help address disparities in health outcomes between members of stigmatized groups and members of non-stigmatized groups. For example, a recent study explored the impact of minority representation cues and communicating organizational diversity philosophies on Black and Latinx participants’ perceptions of a physicians’ racial biases, cultural competence, and general expectations of a visit with that physician. While physicians’ diversity statements did not influence participants’ anticipated quality of the visit, being informed that the physician had a diverse clientele increased greater anticipated comfort and perceptions of receiving better treatment for Black and Latinx participants. Similarly, in another recent study, researchers explored how minority representation cues and physicians’ diversity statements might influence sexual minorities’ perceptions of physician bias, cultural competence, anticipated comfort, expectations, and comfort disclosing their sexuality while visiting a physician. Both the diversity statement and minority representation cues reduced perceptions of physician bias, but only minority representation cues increased perceptions of the physician as culturally competent, increased anticipated comfort and quality, and led to greater comfort disclosing their sexuality. Related work has also been done with fathers in medical contexts. For instance, a 2019 study found that prenatal doctor's offices with environmental safety cues (e.g., pictures of fathers with babies) increased expectant fathers’ comfort with attending prenatal appointments and led to greater parenting confidence, comfort, increased intentions to learn about pregnancy, and greater intentions engage in healthy habits to aid their partner (e.g., avoiding smoking and alcohol during their partner's pregnancy).
See also
Architectural determinism
Health equity
Proxemics
Racial achievement gap in the United States
References
Behavior
Environmental psychology | Identity safety cues | [
"Biology",
"Environmental_science"
] | 3,095 | [
"Behavior",
"Environmental social science",
"Environmental psychology"
] |
69,248,558 | https://en.wikipedia.org/wiki/Ecosection | An ecosection is a biogeographic unit smaller than an ecoregion that contains minor physiographic, macroclimatic or oceanographic variations. They are a virtual ecological zone in the Canadian province of British Columbia, which contains 139 ecosections that vary from pure terrestrial units to pure marine units.
See also
Bioregion
Ecological classification
References
Biogeography
Ecology terminology | Ecosection | [
"Biology"
] | 76 | [
"Ecology terminology",
"Biogeography"
] |
69,249,364 | https://en.wikipedia.org/wiki/List%20of%20nonmetal%20monographs | The purpose of this annotated list is to provide a chronological, consolidated list of nonmetal monographs, which could enable the interested reader to further trace classification approaches in this area. Those marked with a ▲ classify these 14 elements as nonmetals: H, N; O, S; the 4 stable halogens; and the 6 naturally occurring noble gases.
Steudel R 2020, Chemistry of the Non-metals: Syntheses - Structures - Bonding - Applications, in collaboration with D Scheschkewitz, Berlin, Walter de Gruyter, . ▲
An updated translation of the 5th German edition of 2013, incorporating the literature up to Spring 2019. Twenty-three nonmetals, including B, Si, Ge, As, Se, Te, and At but not Sb (nor Po). The nonmetals are identified on the basis of their electrical conductivity at absolute zero putatively being close to zero, rather than finite as in the case of metals. That does not work for As however, which has the electronic structure of a semimetal (like Sb).
Halka M & Nordstrom B 2010, "Nonmetals", Facts on File, New York,
A reading level 9+ book covering H, C, N, O, P, S, Se. Complementary books by the same authors examine (a) the post-transition metals (Al, Ga, In, Tl, Sn, Pb and Bi) and metalloids (B, Si, Ge, As, Sb, Te and Po); and (b) the halogens and noble gases.
Woolins JD 1988, Non-Metal Rings, Cages and Clusters, John Wiley & Sons, Chichester, .
A more advanced text that covers H; B; C, Si, Ge; N, P, As, Sb; O, S, Se and Te.
Steudel R 1977, Chemistry of the Non-metals: With an Introduction to Atomic Structure and Chemical Bonding, English edition by FC Nachod & JJ Zuckerman, Berlin, Walter de Gruyter, . ▲
Twenty-four nonmetals, including B, Si, Ge, As, Se, Te, Po and At.
Powell P & Timms PL 1974, The Chemistry of the Non-metals, Chapman & Hall, London, . ▲
Twenty-two nonmetals including B, Si, Ge, As and Te. Tin and antimony are shown as being intermediate between metals and nonmetals; they are later shown as either metals or nonmetals. Astatine is counted as a metal.
Emsley J 1971, The Inorganic Chemistry of the Non-metals, Methuen Educational, London, . ▲
Twenty nonmetals. H is placed over F; B and Si are counted as nonmetals; Ge, As, Sb and Te are counted as metalloids.
Johnson RC 1966, Introductory Descriptive Chemistry: Selected Nonmetals, their Properties, and Behavior, WA Benjamin, New York. ▲
Eighteen nonmetals. H is shown floating over B and C. Silicon, Ge, As, Sb, Te, Po and At are shown as semimetals. At is later shown as a nonmetal (p. 133).
Jolly WL 1966, The Chemistry of the Non-metals, Prentice-Hall, Englewood Cliffs, New Jersey. ▲
Twenty-four nonmetals, including B, Si, Ge, As, Sb, Te and At. H is placed over F.
Sherwin E & Weston GJ 1966, Chemistry of the Non-metallic Elements, Pergamon Press, Oxford. ▲
Twenty-three nonmetals. H is shown over Li and F; Germanium, As, Se, and Te are later referred to as metalloids; Sb is shown as a nonmetal but later referred to as a metal. They write, "Whilst these heavier elements [Se and Te] look metallic they show the chemical properties of non-metals and therefore come into the category of "metalloids" (p. 64).
Phillips CSG & Williams RJP 1965, Inorganic Chemistry, vol. 1, Principles and non-metals, Oxford University Press, Clarendon. ▲
Twenty-three nonmetals, excluding Sb, including At. An advanced work for its time, presenting inorganic chemistry as the difficult and complex subject it was, with many novel insights.
Yost DM & Russell Jr, H 1946 Systematic Inorganic Chemistry of the Fifth-and-Sixth-Group Nonmetallic Elements, Prentice-Hall, New York, accessed August 8, 2021.
Includes tellurium as a nonmetallic element.
Bailey GH 1918, The Tutorial Chemistry, Part 1: The Non-Metals, 4th ed., W Briggs (ed.), University Tutorial Press, London.
Fourteen nonmetals (excl. the noble gases), including B, Si, Se, and Te. The author writes that arsenic and antimony resemble metals in their luster and conductivity of heat and electricity but that in their chemical properties they resemble the non-metals, since they form acidic oxides and insoluble in dilute mineral acids; "such elements are called metalloids" (p. 530).
Appleton JH 1897, The Chemistry of the Non-metals: An Elementary Text-Book for Schools and Colleges, Snow & Farnham Printers, Providence, Rhode Island
Eighteen nonmetals: He, Ar; F, Cl, Br, I; O, S, Se, Te; N, P, As, Sb; C, Si; B; H. Neon, germanium, krypton and xenon are listed as new or doubtful elements. For Sb, Appleton writes:
"Antimony is sometimes classed as a metal, sometimes as a non-metal. In case of several other elements the question of classification is difficult—indeed, the classification is one of convenience, in a sense, more than one of absolute scientific certainty. In some of its relations, especially its physical properties, antimony resembles the well-defined metals—in its chemical relations, it falls into the group containing boron, nitrogen, phosphorus, arsenic, well-defined non-metals." (p. 166).
Thorpe TE 1896, A Manual of Inorganic Chemistry, vol. 1, The Non-Metals, William Collins, Sons, & Co., London, p. 37
Sixteen nonmetals: Ar; F, Cl, Br, I; O, S, Se, Te; N, P, As; C, Si; B; H.
"In its chemical characters , antimony is closely allied to arsenic on the one hand, and to bismuth on the other; it constitutes, indeed, a connecting link between the metals and the non-metals." (p. 442)
Roscoe HE & Schorlemmer C 1891, A Treatise on Chemistry, Vol. 1 The Nonmetallic Elements, D Appleton and Company, New York
Fifteen nonmetals: H, B, C, Si, N, P, As, O, S, Se, Te, F, Cl, Br, I.
Appleton JH 1888, Beginners' Hand-book of Chemistry: The Subject Developed by Facts and Principles Drawn Chiefly from the Non-metals, Chautauqua Press, New York.
Fifteen nonmetals including B, Si, As, Sb and Se (the six noble gases were not then known; Ge had only been discovered in 1886). Te is shown in a list of the chemical elements but not mentioned elsewhere.
Gmelin L 1849, Handbook of Chemistry, vol. 2, Non-metallic elements, H Watts (trans.), Cavendish Society, London.
Twelve nonmetals (then called "metalloids"): H, B, C, N, O, F, P, S, Cl, Se, Br, I.
Monographs
Chemistry-related lists
Lists of science textbooks | List of nonmetal monographs | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 1,640 | [
"Nonmetals",
"Condensed matter physics",
"nan",
"Materials science"
] |
69,249,374 | https://en.wikipedia.org/wiki/Osmium%20tetrabromide | Osmium tetrabromide is the inorganic compound with the formula OsBr4. A black solid, this compound can be produced by heating osmium tetrachloride and bromine under pressure.
Structure
As determined by X-ray crystallography, osmium tetrabromide is an inorganic polymer. It is isomorphous with platinum tetrabromide and technetium tetrachloride. As such, osmium is in octahedral coordination. Each osmium center bonds to four doubly bridging bromide ligands and two mutually cis terminal bromide ligands.
Related compounds
OsBr3 is the only other binary osmium bromide is that has been crystallized.
References
Bromides
Platinum group halides
Osmium compounds | Osmium tetrabromide | [
"Chemistry"
] | 160 | [
"Bromides",
"Salts"
] |
69,249,998 | https://en.wikipedia.org/wiki/Mercedes-Benz%20MB507%20engine | The Mercedes-Benz MB 507 was a four-stroke, naturally-aspirated, V-12 diesel marine engine; derived from the MB 503 gasoline engine. The MB 507 was also based on the Daimler-Benz DB 603 inverted V-12 aircraft engine, and shared an identical bore, stroke, and displacement. Unlike the gasoline-powered MB 503, the diesel-powered MB 507 did not use a supercharger.
Applications
Panzer VIII Maus V2
References
Mercedes-Benz engines
Engines by model
Diesel engines by model
V12 engines | Mercedes-Benz MB507 engine | [
"Technology"
] | 117 | [
"Engines",
"Engines by model"
] |
69,250,303 | https://en.wikipedia.org/wiki/Mercedes-Benz%20MB517%20engine | The Mercedes-Benz MB 517 was a supercharged, four-stroke, V-12 diesel marine engine version of the MB 507; derived from the MB 503 gasoline engine. The MB 507 was also based on the Daimler-Benz DB 603 inverted V-12 aircraft engine, and shared an identical bore, stroke, and displacement. Unlike the gasoline-powered MB 503, the diesel-powered MB 507 did not use a supercharger.
Applications
Panzer VIII Maus V2
References
Mercedes-Benz engines
Engines by model
Diesel engines by model
V12 engines | Mercedes-Benz MB517 engine | [
"Technology"
] | 120 | [
"Engines",
"Engines by model"
] |
69,250,898 | https://en.wikipedia.org/wiki/Mecachrome%20V634%20engine | The Mecachrome V634 engine (also known as Mecachrome Formula 2 V6) is a 3.4-litre, turbocharged or naturally-aspirated, V6 racing engine, designed, developed and produced by Mecachrome, and is used in the FIA Formula 2 Championship, FIA Formula 3 Championship, and the World Endurance Championship.
Formula 3 engine
First generation (second-generation overall)
The series will remain using the 3.4-litre V6 naturally-aspirated direct-injected engines supplied by Mecachrome until at least the 2021 season due to FIA Formula 3 Championship not being interested in a turbocharged engine. The horsepower will be scaled down from .
Mecachrome V634 F3 V6 engines were crated and shipped to all FIA Formula 3 Championship teams on a serial-number basis as determined by the FIA to ensure equality and fairness in distribution.
Fuel and lubricants components
All Formula 3 cars currently use ordinary unleaded racing gasoline as fuel (similar to commercial vehicle unleaded street gasoline), which has been the de facto standard in third tier single-seater formula racing since the introduction of GP3 Series in 2010. Current Elf LMS 102 RON unleaded gasoline resembles ordinary unleaded gasoline but produces better mileage while being more environmentally-friendly and safer than other fuels. Since 2019, Elf exclusively continues providing the LMS 102 RON unleaded fuel and also Elf HTX 840 0W-40 lubricants for all FIA Formula 3 Championship cars.
Formula 2 engine
The V634 Turbo engine is a V6 turbocharged direct injection four-stroke piston Otto cycle 620 hp fuel-efficient engine developed and built by Mecachrome, and maintained by Teos Engineering. The engine was unveiled in 2017 along with the new Dallara F2 2018 chassis. Dutch turbocharger company Van Der Lee Turbo Systems currently supplies the turbochargers for all FIA Formula 2 Championship engines.
The valve train is a dual overhead camshaft configuration with four valves per cylinder. The crankshaft is made of alloy steel, with five main bearing caps. The pistons are forged aluminium alloy, while the connecting rods are machined alloy steel. The electronic engine management system is supplied by Magneti Marelli, firing a CDI ignition system. The engine lubrication is a dry-sump type, cooled by a single water pump.
The all-new engine fuel delivery system is gasoline direct injection instead of traditional electronic indirect injection. The power output of all-new FIA Formula 2 engine was increased from . Mecachrome will continue providing new FIA Formula 2 engines from the 2018 season and beyond. The Mecachrome V634 Turbo engine is rev limited down to 8,750 rpm and weighs up to including turbocharger. The firing ignition of the Mecachrome V634 Turbo engine is revolutionary digital inductive. The fuel-mass flow restrictor rate of the second-generation FIA Formula 2 Championship engine is roughly rated at .
The Mecachrome V634 Turbo 3.4-litre single-turbocharged direct-injected Mecachrome V6 engine is an evolution of the GP3 engine, which is the solely supplied engine for the FIA Formula 2 Championship. With the addition of a single turbo, the engine underwent rigorous dyno testing, ahead of its racing debut. The Mecachrome V634 Turbo engines sells for up to €67,000 per unit by leasing and rebuilding.
The current second-generation FIA Formula 2 engine allocation is limited to one per season and lasts up to after being rebuilt. Mid-season engine changes, including during race weekends, are banned and may result in a grid penalty for the session.
Turbocharger
Turbochargers were introduced from the start of 2018 season. The turbo configuration is single-turbocharged and produces up to of boost pressure. Dutch turbocharger company Van Der Lee Turbo Systems currently supplies the turbochargers for all FIA Formula 2 Championship all-new engines using the MT134-50120 model. The turbocharger spin limit is 130,000 rpm but cannot exceed 125,000 rpm due to lower turbo boost pressure.
Fuel and lubricants components
All Formula 2 cars currently use ordinary unleaded racing gasoline as fuel (similar to commercial vehicle unleaded street gasoline), which has been the de facto standard in second tier single-seater formula racing since the introduction of GP2 Series in 2005. Current Elf LMS 102 RON unleaded gasoline resembles ordinary unleaded gasoline but produces better mileage while being environmental-friendly and safer than leaded fuels. Since 2005 GP2 Series season, Elf exclusively continues providing the LMS 102 RON unleaded fuel and also Elf HTX 840 0W-40 lubricants for all FIA Formula 2 Championship cars due to in fact of Mecachrome's long-term technical partnership with Elf.
Ginetta LMP1 engine
For the Ginetta G60-LT-P1 racercar to be racing in the LMP1 category. A updated engine was developed with now direct injection opposed to the original port injection F2 engine and a larger turbocharger variant. Originally designed to have a output close to 800hp but power was significantly reduced in its first LeMans 24 outing to improve reliability.
Alpine LMDh engine
For the Alpine A424 LMDh racecar. A new version of the V634 DI engine was developed by Mecachrome with support from Alpines Viry-Chatillon team. The new endurance spec engine is making 675hp and has a redline of 9000rpm.
Applications
Dallara GP3/16
Dallara F3 2019
Dallara F2 2018
Dallara F2 2024
Ginetta G60-LT-P1
Alpine A424
References
External links
Mecachrome official website in French language
Mecachrome official website in English language
FIA Formula 2 official website
FIA Formula 3 official website
Engines by model
FIA Formula 2 Championship
V6 engines
Gasoline engines by model | Mecachrome V634 engine | [
"Technology"
] | 1,215 | [
"Engines",
"Engines by model"
] |
69,251,484 | https://en.wikipedia.org/wiki/List%20of%20digital%20keys%20in%20mobile%20wallets | Digital keys that operate over NFC and/or UWB are compatible with a variety of mobile wallets. These digital keys can be stored in smart devices through the use of mobile wallets that have access to the device's embedded secure element, such as Google Wallet for Android & Wear OS, Samsung Wallet for Android, Huawei Wallet for HarmonyOS, or Apple Wallet for iOS & watchOS.
In China, both Huawei Wallet and Samsung Wallet allow for emulation of unencrypted physical NFC tags. However, these emulated passes must be viewed in their respective Wallet apps before the device is tapped to transmit properly, unlike digital keys that are properly developed for such platforms.
The following is a list of digital keys and for what mobile wallets they are available.
Vehicles
The digital key specification for cars is maintained by the Car Connectivity Consortium. As of 2023, most implementations of the technology follow the Digital Key 2.0 standard. The first automobile to follow the Digital Key 3.0 standard was the BMW iX. Manufacturers can set limits on how many devices a key can be shared with. For instance, Kia only allows 15, while Mercedes-Benz permits up to 32.
Some vehicles may need software or hardware upgrades to support a specific digital wallet. Also, not all trims for these listed models have the necessary hardware to support digital keys.
Keys that are compatible with Google Wallet, Samsung Wallet, and Apple Wallet can be shared across platforms.
Google Wallet, Samsung Wallet, and Apple Wallet are capable of the following remote commands for supported vehicles: unlocking, locking, sounding the horn, and opening/closing the trunk. In addition, Samsung Wallet and Apple Wallet also support remote climate controls.
*Google Wallet for Wear OS only supports BMW and MINI vehicle keys.
Locks
In 2023, a new communication protocol named Aliro was announced by the Connectivity Standards Alliance to promote interoperability between smartphones, smartwatches, and access control readers, and should help guarantee improved availability for digital keys for locks across the major mobile wallets. Google, Samsung, and Apple have all been announced as participating members. The first specification will be available in 2025.
Hospitality and entertainment
Other
References
Near-field communication | List of digital keys in mobile wallets | [
"Technology"
] | 448 | [
"Near-field communication",
"Mobile telecommunications"
] |
69,251,682 | https://en.wikipedia.org/wiki/Toyota%20RV8%20engine | The Toyota RV8 engine family is a series of race car engines designed, developed and produced by Toyota Racing Development. They come in 2.65-liter, 3.0-liter and 3.4-liter, turbocharged and naturally-aspirated, V8 racing engine versions. They are used in the CART series, IRL IndyCar Series, Formula Nippon, Super GT, and Le Mans Prototype sports car racing, from 1996 to 2015. The naturally-aspirated engine, formerly used in Formula Nippon and Super GT, is itself derived from the Toyota Indy V8 Indy car racing V8 engine.
TS030 Hybrid engine
The TS030 uses a naturally aspirated gasoline V8 power unit, mounted at a 90-degree cylinder bank angle, and produces . Toyota engineers elected to base the engine on their Super GT project instead of constructing a new one. The six-speed sequential gearbox unit was transverse-mounted to the engine and the brakes were constructed from carbon materials.
The TS030 Hybrid featured a Kinetic energy recovery system (KERS) regenerative braking device produced by Toyota Racing Development (the Le Mans organisers, Automobile Club de l'Ouest (ACO), use the alternate name ERS) to charge a super capacitor. The extra power is directed to the rear wheels, giving an automatic horsepower increase of . Its motor generator unit acts as a generator under braking; this allows it to harvest direct energy from the drive shaft which slows the car and converts energy into electricity that is stored in the super capacitor, which was supplied by Nisshinbo and mounted in the car's passenger compartment. The result allows for faster lap times when the driver exits track turns and saves fuel by reducing engine usage leaving a corner. Toyota chose Aisin AW to build the front electric motor while Denso were selected to build the rear power unit.
TS040 Hybrid engine
The TS040 Hybrid also uses mid-mounted, naturally-aspirated petrol V8 engine, angled at 90 degrees, was carried over from the TS030 Hybrid. Its displacement, increased from to by lengthening the stroke for better efficiency, supplied to the rear wheels. The engine was developed to run with a fuel flow metre promoting a concept switch to efficiency from power. The bosses-mounted injection system were in the inlet tract and placed over the angled throttle valves relative to the inlet path. They were fitted with eight solenoid injectors which sent power each of the throttle runners and into the inlet portlets. Toyota installed two systems featuring knock control to detect vibration and real-time combustion pressure sensors to tune the spark timing among other engine components during a race for reliability purposes.
Applications
Formula Nippon/Super Formula
Lola B06/51
Swift 017.n
LMP1
Lola B10/60
Toyota TS030 Hybrid
Toyota TS040 Hybrid
Super GT (GT300)
Toyota Prius APR GT
CART/IndyCar series
Reynard 96I
Reynard 97I
Reynard 98I
Eagle MK-V
Eagle 987
Eagle 997
Reynard 02I
Lola B02/00
Swift 010.c
References
External links
Toyota engines
Toyota in motorsport
IndyCar Series
Champ Car
Super Formula
V8 engines
Gasoline engines by model
Engines by model | Toyota RV8 engine | [
"Technology"
] | 659 | [
"Engines",
"Engines by model"
] |
69,253,195 | https://en.wikipedia.org/wiki/Ericson%20fluctuations | Ericson fluctuations constitute one of the most characteristic features of quantum chaotic scattering in the regime of strongly overlapping resonances such as a compound nucleus. These fluctuations were predicted in 1960 by Torleif Ericson in two seminal articles, further developed in 1963, based on the same statistical assumptions as those used by E. Wigner, C. E. Porter and R. G. Thomas to describe generic properties of resonances in long-lived compound nuclear systems. In the present case the fluctuations occur in the "continuum" regime for which a large number of such resonances overlap coherently, owing to the short lifetime of the compound nucleus. At the time it was believed that this would lead to a structure-less behavior. Ericson realized that the opposite was the case with strong, random fluctuations.
The Ericson fluctuations were first observed in 1964 by P. Von Brentano et al. in nuclear physics giving rise to a vigorous theoretical and experimental programme. They have the curious feature of being both reproducible and random at the same time. The fluctuations are universal and have later been observed in many other areas such as photoionization of hydrogen, uni-molecular dissociation (physical chemistry), perturbed atomic and molecular systems and micro wave billiards.
Present theoretical descriptions of chaotic quantum scattering confirm the predicted properties of the Ericson fluctuations. The universality of the Ericson fluctuations are thus very well established.
References
Nuclear physics
Scattering theory
Interference | Ericson fluctuations | [
"Physics",
"Chemistry"
] | 294 | [
"Scattering",
"Scattering theory",
"Nuclear physics"
] |
69,253,835 | https://en.wikipedia.org/wiki/Online%20brand%20defense | Online brand defense is a concept in consumer behavior. It refers to the situation where a consumer defends a brand against criticisms on online platforms. The reason why a consumer does this varies. It might be due to attachment to the brand. It could also be due to belief in the brand's high product quality leading to the perception that the criticisms are unjustified.
Since the early 21st century, the concept of online brand defense has drawn scholarly interest within the field of marketing, in particular consumer psychology. Many experts in this field have been discussing ways to induce online brand defense in one's customers, because such behavior is thought to help defend the brand against negative word-of-mouth.
Examples
Former Democratic Party Hong Kong chairperson Emily Lau once openly complained Cathay Pacific, stating there was no beef in the beef porridge served. Owing to Lau's political stance, she was attacked by some internet users who disliked her.
Lisa Ch'ng once openly complained about the services of Cathay Pacific, along with breaching the privacy of cabin crew. Hong Kong Airlines (a main rival of Cathay Pacific) implicitly mentioned the incident on social media, which triggered the attack from Matt Yeung, the boyfriend of Lisa Ch'ng. In turn, both were criticized heavily by many internet users. Some users criticized Yeung for being arrogant solely by appealing to Chinese nationalism and patriotism.
See also
Brand relationship
Quality management
Word-of-mouth marketing
References
Brands
Consumer behaviour | Online brand defense | [
"Biology"
] | 297 | [
"Behavior",
"Consumer behaviour",
"Human behavior"
] |
69,257,395 | https://en.wikipedia.org/wiki/Pollux%20Peak | Pollux Peak is an mountain summit located in Yellowstone National Park, in Park County, Wyoming, United States.
Description
The peak is situated in the northeast quadrant of Yellowstone National Park and is the fourth-highest peak within the park. It is part of the Absaroka Range, which is a subset of the Rocky Mountains. Neighbors include Castor Peak to the southwest, and Saddle Mountain to the northwest on the opposite side of the Lamar River Valley. Topographic relief is significant as the northwest aspect rises over above Lamar River in approximately 1.5 mile. Pollux Peak is named for Pollux, the twin half-brother of Castor according to Greek mythology, and these two gods were considered protectors of travelers, of which there are many in Yellowstone Park. The mountain's name, which was officially adopted in 1930 by the United States Board on Geographic Names, was in use before 1899 when Henry Gannett published it in A Dictionary of Altitudes in the United States.
Climate
According to the Köppen climate classification system, Pollux Peak is located in a subarctic climate zone with long, cold, snowy winters, and cool to warm summers. Winter temperatures can drop below −10 °F with wind chill factors below −30 °F. Precipitation runoff from the mountain drains into tributaries of the Lamar River.
See also
List of mountains and mountain ranges of Yellowstone National Park
References
External links
Weather forecast: Pollux Peak
Mountains of Park County, Wyoming
Mountains of Wyoming
Three-thousanders of the United States
Mountains of Yellowstone National Park
Castor and Pollux | Pollux Peak | [
"Astronomy"
] | 309 | [
"Castor and Pollux",
"Astronomical myths"
] |
69,257,549 | https://en.wikipedia.org/wiki/Honda%20HR09E/HR10EG%20engine | The Honda HR-09E and Honda HR-10EG are 3.4-liter, naturally-aspirated, V8 racing engines, developed and produced by Honda for use in Formula Nippon and Super GT, starting in 2009.
HR10EG
The HR10EG V8 engine was based on the HR09E built for Formula Nippon. On December 22, 2009, Honda announced the HSV-010 GT as the successor to the NSX Super GT in the Super GT series.
For the 2011 season, the HSV-010 GT's radiator was divided in two and relocated to the sides of the car, with the goal of quicker cornering via a reduced moment of inertia with respect to yaw.
For the 2013 season, the last season under 2009 regulations, the radiator was moved back to the front of the car with lightened equipment. Instead, a shorter exhaust system with exhaust exits on both sides was used, allowing the V8 engine to rev higher. The HSV-010 GT's overall potential was improved, with the #17 Keihin HSV-010 placing second overall in the Teams' Championship.
Applications
Swift 017.n
Honda HSV-010 GT
References
External links
Honda Performance Development official website
Engines by model
Gasoline engines by model
Honda engines
Super Formula
Super GT
V8 engines | Honda HR09E/HR10EG engine | [
"Technology"
] | 275 | [
"Engines",
"Engines by model"
] |
70,752,698 | https://en.wikipedia.org/wiki/Stefan%20H%C3%BCfner | Stefan Hüfner (July 2, 1935 in Löwenberg, Silesia – January 17, 2013 in Saarbrücken, Saarland) was a German experimental physicist specialized in solid-state physics and photoemission spectroscopy.
Education and career
Hüfner studied mathematics and physics at the Goethe University of Frankfurt and the Technical University of Darmstadt. After graduating from 1960 to 1966, he was a scientific assistant at the Institute for Technical Physics at the TU Darmstadt. In 1963 he received his doctorate there, supervised by Karl-Heinz Hellwege. In 1966 he obtained habilitation in physics. He was a guest researcher at the Technical University of Munich and at the Bell Telephone Laboratories in Murray Hill, N.Y., USA. From 1967 to 1968 he was a privatdozent at the TU Darmstadt and the doctoral supervisor of Peter Grünberg, who was awarded the Nobel Prize in Physics in 2007.
In 1968 he received a call to the professorship for experimental physics at the Free University of Berlin as the successor to Professor Gerhard Simonsohn. In 1975, Hüfner moved to the professorship for experimental physics at Saarland University. In 1994 he became founding speaker of the Collaborative Research Center "Interface-determined Materials". In 2001 he took over the office of university vice president for planning and strategy, which he held until the beginning of 2003. In September 2003 he retired.
Honors and awards
Hüfner was an emeritus member of the advisory board of the Max Planck Institute for Nuclear Physics in Heidelberg, the Max Planck Institute for Physics in Munich, the Max Planck Institute for Plasma Physics in Greifswald and Munich and the Max Planck Institute for Quantum Optics in Munich and other advisory boards of the Max Planck Society. Since 2004 he has been a member and chairman of the Technical Committee for Engineering Sciences of the Elite Network of Bavaria. In 2006/2007 he was a visiting professor at the University of British Columbia in Vancouver, Canada.
He received honorary doctorates from the University of Fribourg and the Free University of Berlin.
Works
Hüfner authored the classic textbook on photoemission spectroscopy, first published in 1995 and has gone through three editions in total.
In addition to numerous scientific publications, Hüfner has also written several novels, including Der Tote von Dresden (Conte Verlag 2004, ) and Artikel eins. Ein Zukunftsroman (Conte Verlag 2006, ).
Bibliography
Textbooks and monographs
Fictions
Reviews
See also
Jürgen Kirschner
References
External links
Universität des Saarlandes: „Neuer Vizepräsident: Stefan Hüfner“, Januar 2001
2013 deaths
1935 births
Academic staff of Saarland University
Academic staff of the Free University of Berlin
20th-century German physicists
German materials scientists
German experimental physicists
Condensed matter physicists
Scientists at Bell Labs
Goethe University Frankfurt alumni
Technische Universität Darmstadt alumni
Academic staff of Technische Universität Darmstadt
People from Lwówek Śląski | Stefan Hüfner | [
"Physics",
"Materials_science"
] | 610 | [
"Condensed matter physicists",
"Condensed matter physics"
] |
70,752,806 | https://en.wikipedia.org/wiki/Data%20Management%20Association | The Data Management Association (DAMA), formerly known as the Data Administration Management Association, is a global not-for-profit organization which aims to advance concepts and practices about information management and data management. It describes itself as vendor-independent, all-volunteer organization,
and has a membership consisting of technical and business professionals. Its international branch is called DAMA International (or DAMA-I), and DAMA also has various continental and national branches around the world.
History
The Data Management Association International was founded in 1980 in Los Angeles. Other early chapters were:San Francisco, Portland, Seattle, Minneapolis, NewYork, and Washington D.C.
Data Management Body of Knowledge
DAMA has published the Data Management Body of Knowledge (DMBOK), which contains suggestions on best practices and suggestions of a common vernacular for enterprise data management. The first edition (DAMA-DMBOK) was published on 2009 November 1, and the second edition (DAMA-DMBOK2) was published on 2017 July 1.
DMBOK has been described by the authors as being an "equivalent" to the Project Management Body of Knowledge (PMBOK) and Business Analysis Body of Knowledge (BABOK). It encompasses topics such as data architecture, security, quality, modelling, governance, big data, data science, and more.
DAMA also provides a professional data management certification for individuals known as a Certified Data Management Professional (CDMP), which is based on the DMBOK as a study reference. It is an example of one of many competing certifications for data management professionals.
See also
Data management
References
External links
DAMA INTERNATIONAL
Data management
Bodies of knowledge
Standards organizations | Data Management Association | [
"Technology"
] | 344 | [
"Data management",
"Data"
] |
70,753,866 | https://en.wikipedia.org/wiki/Polyetherketones | Polyetherketones (PEK for short) are polymers whose molecular backbone contain alternating ketone (R-CO-R) and Ether (R-O-R) functionalities. The most common are Polyaryletherketones (PAEK), in which there is an aryl group linked in the (1–4)-position between each of the functional groups. The backbone, which is thus very rigid, gives the materials very high glass transition and melting temperatures compared to other plastics.
Synthesis
Polyetherketones can be obtained by condensation of 4,4′-difluorobenzophenone and potassium or sodium salt of hydroquinone:
Types
The most common of these high-temperature resistant materials is polyetheretherketone (PEEK).
Other types of polyetherketone are:
PEKK = Polyetherketoneketone
PEEKK = Polyether ether ketone ketone
PEKEKK = Polyetherketoneetherketoneketone
Applications
Space and aviation: aircraft parts (fins, wing flaps, nose caps, seats). Replacements for metal parts, also in the military field.
Machinery and automotive industry: high-performance molded parts such as bearing cages, gears, sealing rings, valve spring retainers, impellers. Coatings when high resistance to temperatures above 200 °C is required. Coatings made of PEEK or PEK, for example, are suitable for applications up to 230 °C (450 °F).
Electronics industry: wire and cable sheathing, flexible printed circuit boards, semiconductor production, offshore connectors.
Medical technology: endoscope handles, hip joint prostheses. Because polyetherketones can be sterilized without damaging them, PEK is often used for surgical applications.
Properties
PEK has a high temperature resistance. It is also characterized by high wear resistance. In addition, polyetherketones are highly resistant to chemicals: They are resistant to non-oxidizing acids, grease, lubricants, water vapor, hot water, and concentrated alkalis.
Literature
Beland, S. (1990). High performance thermoplastic resins and their composites. William Andrew.
Díez-Pascual, A. M., Naffakh, M., Marco, C., Ellis, G., & Gómez-Fatou, M. A. (2012). High-performance nanocomposites based on polyetherketones. Progress in Materials Science, 57(7), 1106–1190.
References
Ethers
Ketones
Polymers | Polyetherketones | [
"Chemistry",
"Materials_science"
] | 537 | [
"Ketones",
"Functional groups",
"Organic compounds",
"Ethers",
"Polymer chemistry",
"Polymers"
] |
70,754,760 | https://en.wikipedia.org/wiki/Ghislenghien%20disaster | The Ghislenghien disaster was an explosion of a natural gas pipeline in Ghislenghien (a village in the municipality of Ath, Belgium) on 30 July 2004. It was caused by a natural gas leak resulting from damage caused by a construction vehicle. The explosion and fire killed 24 people (primarily first responders) and injured 132.
It was the worst industrial disaster in Belgium since the 1956 Marcinelle mining disaster and is one of the worst peacetime disasters in the country's history.
The disaster led to a reform of the civil security service in Belgium.
Accident
Two gas pipelines link Norway to Paris through Zeebrugge, Belgium, and provides natural gas for France, Spain and Italy. Several weeks before the explosion, during construction of a factory in the Ghislenghien industrial zone, a piece of heavy equipment scratched a Fluxys high-pressure gas pipeline.
At 8:56 AM on 30 July 2004, while firefighters and Electrabel technicians were working to repair the leak, the pipeline exploded, following an increase of pressure in the pipe. A column of flames nearly 100 meters high raised into the sky. It was visible 15 kilometers away. A section of pipe measuring 11 meters and weighing multiple tons was sent flying 200 meters away. Due to the effects of the heat, electrical systems melted in nearby buildings hundreds of meters away. Heat was felt in a two-kilometer radius. Debris and building materials from the explosion were projected around a six kilometer radius.
An earthquake lasting over ten minutes was felt as far as Sirault, 20 kilometers away. The sound from the explosion was heard in numerous neighborhoods of south-eastern Brussels (Uccle, Linkebeek, Watermael).
The disaster killed 24 people (21 Belgian nationals and 3 French) and injured 132. Among the deceased were 5 members of the Fire Department of Ath (including the chief, Eddy Pettiaux) and police officer Pierre Dubois.
The five firefighters, the police officer and the Electrabel worker were given state funeral honors.
The last victim died in June 2005 due to complications from their burn injuries.
On 31 July, King Albert II returned from a state visit to Sweden to meet with victims' families. The day before, Prince Laurent and Prime Minister Guy Verhofstadt met with the families.
Investigation
A trial, aimed at establishing responsibility for the disaster, ran from 15 June 2009, to 22 February 2010, at the Court in Tournai. Eleven of the fourteen defendants were acquitted, including the municipality of Ath, Fluxys, and Husqvarna, the sponsor of the factory construction project. The three people found guilty were charged with "involuntary homicide by lack of foresight or precaution". Those charged included the architect responsible for the project, Tramo, the company involved in the project, and the construction manager.
On 28 June 2011, at the Court of Appeal in Mons, Judge Jean-François Jonckheer, rendered a judgement on the case. Judge Jonckheer's judgement revises many of the lower court's rulings and challenges the case law on several points. The appeals court found Fluxys responsible for the disaster, as well as Diamant Boart (now Husqvarna Belgium). Additionally, the Tramo company was acquitted. Fluxys introduced an appeal in cassation.
Aftermath
Reform of the Civil Security Service
Following the disaster, the government passed Law 15, which reformed the Belgian civil security services. By 2014, this led to the creation of emergency zones, which replaced regional fire services, which were previously under local control.
Regulations
In Belgium, the establishment of a cadastral survey of underground cables and pipes has been envisaged since 2007.
In France, regulations on the execution of construction projects DT-DICT was strengthened in 2012.
Additionally, a government order on 4 August 2006, imposed a revision of safety standards on gas pipelines, notably conducting hazard studies and reinforcing pipelines with HDPE plating to protect from possible construction damage.
References
Industrial fires and explosions
2004 disasters in Belgium
Fires in Belgium
July 2004
Explosions in Belgium
2004 in Belgium
Ath | Ghislenghien disaster | [
"Chemistry"
] | 843 | [
"Industrial fires and explosions",
"Explosions"
] |
70,758,152 | https://en.wikipedia.org/wiki/Cookeina%20tricholoma | Cookeina tricholoma, also known by its common name bristly tropical cup, is a species of fungus from the genus Cookeina.
References
Sarcoscyphaceae
Taxa named by Camille Montagne
Fungi described in 1834
Fungus species | Cookeina tricholoma | [
"Biology"
] | 50 | [
"Fungi",
"Fungus species"
] |
70,758,621 | https://en.wikipedia.org/wiki/Sony%20Xperia%201%20IV | The Sony Xperia 1 IV is an Android smartphone manufactured by Sony. Launched on May 11, 2022, it succeeds the Xperia 1 III as the latest flagship of Sony's Xperia series. The device was announced along with the mid-range Xperia 10 IV, with expected release dates by June 2022 (Asian markets) and as late as September 2022 for other markets including the US. US shipments were delayed and ultimately began in late October 2022.
Design
The Xperia 1 IV is designed with more professionalism in mind, while improving on the now-signature designs of its predecessors, the Xperia 1 II and Xperia 1 III. It features a grippier matte frame and rear frosted glass finish akin to the Xperia PRO-I, and a boxier design than the previous flagships. The phone has Corning Gorilla Glass Victus protection both on the front and the back as well as IP65 and IP68 certifications for water resistance.
The display still has symmetrical bezels on the top and the bottom, a hallmark Xperia design, where the front-facing dual stereo speakers and the front camera are placed. The left side of the phone is completely devoid of any controls or ports, with only antenna bands present. The microSD/SIM card combo tray now found at the bottom (or right-side if placed in landscape) along with the USB-C 3.2 port and the primary microphone, while the right side contains the fingerprint reader embedded into the power button, a volume rocker, and a dedicated 2-stage shutter button with an embossed finish, the previously included customisable shortcut button from the Mark 3 omitted. Xperia 1 IV is also the last Xperia 1 series to feature LED notification light as Xperia 1 V removed the feature the following year.
The rear cameras are arranged in a vertical strip like its predecessor, with the LED flash and color spectrum sensor along the top. The phone will be available in three colors: Black, White, and Purple, with only Black and Purple being available in the North American market.
Specifications
Hardware
The Xperia 1 IV is powered by the 4 nm (4LPE) Qualcomm Snapdragon 8 Gen 1 SoC and an Adreno 730 GPU, accompanied by 12 GB of LPDDR5 RAM, 256 GB or 512 GB storage space (expandable up to 1 TB), and single/dual-hybrid nano-SIM card slot depending on region. The phone features a 21:9 4K CinemaWide HDR 10-bit 120 Hz OLED display first seen in the Xperia 1 III, now improved with 50% more brightness. The Xperia 1 IV's touch sampling rate is 240 Hz. The phone has a larger 5000 mAh battery (from 4500 mAh of the 1 III), and supports 30 W Fast Charging alongside Qi wireless charging with reverse wireless charging support. The phone has front-facing dual stereo speakers with redesigned drivers, and support for 360 Reality Audio. There is also a 3.5 mm stereo audio jack with support for both high-resolution audio output as well as microphone input for plugged in peripherals such as an external microphone for vlogging.
Camera
The Xperia 1 IV has an improved triple camera setup from the 1 III. All three cameras are still 12 Megapixels, but sporting new sensors and optics for the ultrawide and telephoto. They consist of the main 12 MP Exmor RS IMX557 sensor behind a 24 mm f/1.7 lens with optical image stabilization (OIS), an ultrawide 12MP IMX563 sensor with 16 mm f/2.2 lens, both of which have phase-detection autofocus, and a 0.3 MP IMX316 3D TOF depth sensor. The latter is also the final time it was included in any Sony Xperia device as Xperia 1 V removes the 3D TOF depth sensor and RGBC-IR sensor as well.
The highlight of the 1 IV is its continuous zoom telephoto lens, a major improvement over its predecessor's variable zoom telephoto. It is a 12 MP 1/3.5" sensor with 1.0 μm pixels and PDAF, contained in the same periscope design like the 1 III, it can now zoom between 85mm all the way up to 125mm without any stepping or using digital zoom, just like a true digital camera. There is no confirm detail on the specific Sony IMX sensor used on the telephoto, other than some insights by independent reviewers such as GSMArena where they've discovered that it is "presumably" an IMX650, a 40-MP sensor with a 1/1.7-inch optical format that was last used on the Huawei P30 and P30 Pro smartphones. Whether or not this is true, either implementing the same 12-MP crop as the Xperia PRO-I on the IMX650, or the hardware information app HWiNFO used could be reporting incorrect data (which according to Notebookcheck seems unlikely), or if it's using a new or unknown IMX sensor altogether, remains to be seen.
All 3 cameras of the 1 IV use ZEISS T✻ (T-Star) anti-reflective coating on each lens and has support for 4K video recording up to 120 FPS and 2K for up to 120 FPS like its predecessors, and it improves on the 20 FPS burst feature where it is now available on all 3 cameras. Digital zoom on the main camera can reach the equivalent of 300mm with the "AI super resolution zoom" first featured on the 1 III. It also has improved Realtime Tracking with enhanced Eye AF for human, animals and birds, instantly locking focus on the subject's eyes without losing track upon sudden loss of focus from the frame.
For the first time, a new 12 MP front-facing camera with support for 4K video recording is present in the 1 IV. Surprisingly, it is the Sony IMX663 (in place of the previous Samsung ISOCELL sensor), the same sensor that was first used as the telephoto sensor for the Xperia 1 III and the Xperia PRO-I, making it on-par with the likes of Google's Pixel 6 Pro smartphone and marking another improvement over its predecessors' outdated 8 MP-resolution front cameras.
Software
The Xperia 1 IV runs on the latest Android 12, with promise for 2 major Android software revisions and 3 years of software support. It is also equipped with 3 different camera apps specifically made to take advantage of the 1 IV's camera hardware: "Photo Pro", developed by Sony's α (Alpha) camera division, focuses on the full manual control setup and configuration commonly seen on Sony Alpha line of professional cameras; the professional movie-oriented "Cinema Pro", developed by Sony's cinematography division CineAlta, and the "Basic Mode" first seen on the 1 III, replacing the stock camera app but with additional controls from the "Photo Pro".
See also
List of longest smartphone telephoto lenses
Notes
References
Android (operating system) devices
Flagship smartphones
Sony smartphones
Mobile phones introduced in 2022
Mobile phones with multiple rear cameras
Mobile phones with 4K video recording | Sony Xperia 1 IV | [
"Technology"
] | 1,502 | [
"Flagship smartphones"
] |
70,760,919 | https://en.wikipedia.org/wiki/Nail%20brace | A nail correction brace, also known as an orthonyxic brace or simply a nail brace, is a medical device used to correct the misalignment of fingernails or toenails in order to prevent the nails from growing in. Treatment is usually carried out by a podiatrist or the general practitioner. The latter can also prescribe the nail brace. It is a conservative treatment that can help avoid a surgical intervention.
The nail brace can be made of steel wire or plastic. The brace itself is inserted into the nail fold on both sides and fixed in the middle of the nail. Duration of treatment varies according to severity and averages around six months. During this time, the braces are easily relocated depending on the nail growth. The nail is thus held over the nail fold on both sides during its growth. This prevents it from growing in again. The brace does not cause any hindrance for sports (including swimming) etc.
The first known patents were submitted by Edward E. Stedman in 1872 and 1873 in Ohio (United States). The 1873 patent was later described and illustrated by doctor William Scholl in his textbook The Human Foot. Anatomy, deformities and treatment. In 1960s, the Scottish chiropodist Ross Fraser came up with the neologism orthonyxia and invented his own nail brace. This model was put into production and the idea of nail bracing treatment spread worldwide.
Studies find that various braces have high success rate in treatment of ingrown nails, and result in lesser pain and better patient satisfaction than surgical methods.
References
Podiatry
Medical devices | Nail brace | [
"Biology"
] | 327 | [
"Medical devices",
"Medical technology"
] |
70,761,613 | https://en.wikipedia.org/wiki/Xanthoparmelia%20cumberlandia | Xanthoparmelia cumberlandia is a lichen which belongs to the Xanthoparmelia genus. It is also known as a member of the rockfrong lichens due to its coloration.
Description
Grows to around 6–12 cm in diameter with irregular lobate lobes. The upper surface of the lichen has rounded lobed tips with yellow-green or blueish green areas on the surface.
Habitat and range
Commonly found attached to acid rocks in sheltered and semi-sheltered open coastal and intermontane areas at lower elevations as such it is commonly found in across North America except in deserts and open plains.
Chemistry
Xanthoparmelia cumberlandia produces constictic, norstictic, stictic, norstictic, usnic and menegazzic acids.
Taxonomy
The lichen was first formally described under the name Parmelia cumberlandia in 1847.
See also
List of Xanthoparmelia species
References
cumberlandia
Lichen species
Lichens of North America
Lichens described in 1934
Taxa named by Vilmos Kőfaragó-Gyelnik | Xanthoparmelia cumberlandia | [
"Biology"
] | 222 | [
"Fungus stubs",
"Fungi"
] |
70,762,414 | https://en.wikipedia.org/wiki/N-Acetyltryptamine | N-Acetyltryptamine is an organic compound with the molecular formula C12H14N2O. It is a partial agonist for the melatonin receptors. N-Acetyltryptamine is produced by Streptomyces djakartensis and other Streptomyces and Fusarium species.
References
Further reading
Acetamides
Tryptamines | N-Acetyltryptamine | [
"Chemistry"
] | 82 | [
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
70,762,463 | https://en.wikipedia.org/wiki/Speciociliatine | Speciociliatine is a major alkaloid of the plant Mitragyna speciosa, commonly known as kratom. It is a stereoisomer of Mitragynine and constitutes 0.00156 - 2.9% of the dried leaf material.
Pharmacology
Pharmacodynamics
Speciociliatine has found to be a ligand of the mu and kappa opioid receptors, however findings are varied as to whether it functions as an agonist or a competitive antagonist at those sites.
Pharmacokinetics
A preliminary pharmacokinetic analysis in male Sprague Dawley rats determined the elimination half-life of Speciociliatine to be 2.6 - 5 hours and the absolute bioavailability to be 20.7% (at an oral dose of 20 mg/kg).
References
Indoloquinolizines
Tryptamine alkaloids
Methyl esters
Methoxy compounds | Speciociliatine | [
"Chemistry"
] | 197 | [
"Tryptamine alkaloids",
"Alkaloids by chemical classification"
] |
70,762,688 | https://en.wikipedia.org/wiki/H3T6P | H3T6P is an epigenetic modification to the DNA packaging protein histone H3. It is a mark that indicates the phosphorylation of the 6th threonine residue of the histone H3 protein.
H3S10P and H3T6P levels are higher in cervical cancer cells and are responsible for cellular transformation.
The writing of H3T6P by androgen-dependent kinase signaling precludes the removal of active methyl tags from H3K4 during AR-stimulated gene expression. H3T6P levels are positively correlated with high Gleason scores in prostate carcinomas.
Nomenclature
The name of this modification indicates the protein phosphorylation of threonine 6 on histone H3 protein subunit:
Serine/threonine/tyrosine phosphorylation
The addition of a negatively charged phosphate group can lead to major changes in protein structure, leading to the well-characterized role of phosphorylation in controlling protein function. It is not clear what structural implications histone phosphorylation has, but histone phosphorylation has clear functions as a post-translational modification.
Effect of modification
H3S10P and H3T6P levels are higher in cervical cancer cells and are responsible for cellular transformation.
The writing of H3T6P by androgen-dependent kinase signaling precludes the removal of active methyl tags from H3K4 during AR-stimulated gene expression. PKCbeta(I) and H3T6P levels are positively correlated with high Gleason scores in prostate carcinomas. Inhibiting PKCbeta(I) reduces AR-induced tumor cell proliferation in vitro and cancer progression in vivo.
Histone modifications
The genomic DNA of eukaryotic cells is wrapped around special protein molecules known as histones. The complexes formed by the looping of the DNA are known as chromatin.
Post-translational modification of histones such as histone phosphorylation has been shown to modify the chromatin structure by changing protein:DNA or protein:protein interactions. Histone post-translational modifications modify the chromatin structure. The most commonly associated histone phosphorylation occurs during cellular responses to DNA damage, when phosphorylated histone H2A separates large chromatin domains around the site of DNA breakage. Researchers investigated whether modifications of histones directly impact RNA polymerase II directed transcription. Researchers choose proteins that are known to modify histones to test their effects on transcription, and found that the stress-induced kinase, MSK1, inhibits RNA synthesis. Inhibition of transcription by MSK1 was most sensitive when the template was in chromatin, since DNA templates not in chromatin were resistant to the effects of MSK1. It was shown that MSK1 phosphorylated histone H2A on serine 1, and mutation of serine 1 to alanine blocked the inhibition of transcription by MSK1. Thus results suggested that the acetylation of histones can stimulate transcription by suppressing an inhibitory phosphorylation by a kinase as MSK1.
Mechanism and function of modification
Phosphorylation introduces a charged and hydrophilic group in the side chain of amino acids, possibly changing a protein's structure by altering interactions with nearby amino acids. Some proteins such as p53 contain multiple phosphorylation sites, facilitating complex, multi-level regulation. Because of the ease with which proteins can be phosphorylated and dephosphorylated, this type of modification is a flexible mechanism for cells to respond to external signals and environmental conditions.
Kinases phosphorylate proteins and phosphatases dephosphorylate proteins. Many enzymes and receptors are switched "on" or "off" by phosphorylation and dephosphorylation. Reversible phosphorylation results in a conformational change in the structure in many enzymes and receptors, causing them to become activated or deactivated. Phosphorylation usually occurs on serine, threonine, tyrosine and histidine residues in eukaryotic proteins. Histidine phosphorylation of eukaryotic proteins appears to be much more frequent than tyrosine phosphorylation. In prokaryotic proteins phosphorylation occurs on the serine, threonine, tyrosine, histidine or arginine or lysine residues. The addition of a phosphate (PO43-) molecule to a non-polar R group of an amino acid residue can turn a hydrophobic portion of a protein into a polar and extremely hydrophilic portion of a molecule. In this way protein dynamics can induce a conformational change in the structure of the protein via long-range allostery with other hydrophobic and hydrophilic residues in the protein.
Epigenetic implications
The post-translational modification of histone tails by either histone-modifying complexes or chromatin remodeling complexes is interpreted by the cell and leads to complex, combinatorial transcriptional output. It is thought that a histone code dictates the expression of genes by a complex interaction between the histones in a particular region. The current understanding and interpretation of histones comes from two large scale projects: ENCODE and the Epigenomic roadmap. The purpose of the epigenomic study was to investigate epigenetic changes across the entire genome. This led to chromatin states, which define genomic regions by grouping different proteins and/or histone modifications together.
Chromatin states were investigated in Drosophila cells by looking at the binding location of proteins in the genome. Use of ChIP-sequencing revealed regions in the genome characterized by different banding. Different developmental stages were profiled in Drosophila as well, an emphasis was placed on histone modification relevance. A look in to the data obtained led to the definition of chromatin states based on histone modifications. Certain modifications were mapped and enrichment was seen to localize in certain genomic regions.
The human genome is annotated with chromatin states. These annotated states can be used as new ways to annotate a genome independently of the underlying genome sequence. This independence from the DNA sequence enforces the epigenetic nature of histone modifications. Chromatin states are also useful in identifying regulatory elements that have no defined sequence, such as enhancers. This additional level of annotation allows for a deeper understanding of cell specific gene regulation.
Methods
The histone mark can be detected in a variety of ways:
1. Chromatin Immunoprecipitation Sequencing (ChIP-sequencing) measures the amount of DNA enrichment once bound to a targeted protein and immunoprecipitated. It results in good optimization and is used in vivo to reveal DNA-protein binding occurring in cells. ChIP-Seq can be used to identify and quantify various DNA fragments for different histone modifications along a genomic region.
2. Micrococcal Nuclease sequencing (MNase-seq) is used to investigate regions that are bound by well-positioned nucleosomes. Use of the micrococcal nuclease enzyme is employed to identify nucleosome positioning. Well-positioned nucleosomes are seen to have enrichment of sequences.
3. Assay for transposase accessible chromatin sequencing (ATAC-seq) is used to look in to regions that are nucleosome free (open chromatin). It uses hyperactive Tn5 transposon to highlight nucleosome localisation.
References
Epigenetics
Post-translational modification | H3T6P | [
"Chemistry"
] | 1,616 | [
"Post-translational modification",
"Gene expression",
"Biochemical reactions"
] |
70,762,697 | https://en.wikipedia.org/wiki/Boudabousia | Boudabousia is a genus of bacteria from the family of Actinomycetaceae.
References
Actinomycetales
Bacteria genera
Taxa described in 2018 | Boudabousia | [
"Biology"
] | 35 | [
"Bacteria stubs",
"Bacteria"
] |
70,764,490 | https://en.wikipedia.org/wiki/Bj%C3%B6rn%20Ekwall | Björn Ekwall (13 June 1940 – 19 August 2000) was a Swedish cell toxicologist, known for his pioneering work in in vitro toxicology.
Biography
Ekwall was born in Uppsala in 1940. He studied at Uppsala University Medical School and got his Doctor of Medicine degree in 1969. After a short time, he served as a lecturer at the Department of Anatomy at Uppsala University. He completed his PhD at the same university and was a postdoc for six months at Materials Science Technology Laboratories, Memphis, Tennessee, between 1981 and 1982.
During 1982-1983 he worked as a consultant at the Toxicology Laboratory of the Swedish Food Administration. In 1983 he founded the Cytotoxicology Laboratory (CTLU) in Uppsala.
Selected work and publications
Ekwall is known for his two main projects: Multicentre Evaluation of In Vitro Cytotoxicity (MEIC) and Evaluation-Guided Development of In Vitro Toxicity and Toxicokinetic Tests (EDIT) which became basis for later international EU projects such as ACuteTox, Sens-it-iv and ReProTect. MEIC evaluated the usefulness of in vitro tests for the estimation of human acute systemic toxicity. Started in 1999, the purpose of EDIT was to establish and validate in vitro tests relevant to toxicokinetics and for organ-specific toxicity, to be incorporated into optimal test batteries for the estimation of human acute systemic toxicity.
He has authored and co-authored many publications, including the following:
Toxicity to HeLa cells of 205 drugs as determined by the metabolic inhibition test supplemented by microscopy, Toxicology, 17 (1980), pp. 273–295
Preliminary studies on the validity of in vitro measurement of drug toxicity using HeLa cells II. Drug toxicity in the MIT-24 system compared with mouse and human lethal dosage of 52 drug, Toxicology Letters, 5 (1980), pp. 309–317
MEIC- a new international multicenter project to evaluate the relevance to human toxicity of in vitro cytotoxicity tests, Cell Biology and Toxicology, 5 (1989), pp. 331–347
Overview of the final MEIC results II. The in vitro/in vivo evaluation, including a selection of a practical battery of cell tests for prediction of acute lethal blood concentrations in human, Toxicology in Vitro, 13 (1999), pp. 665–673
EDIT: a new international multicenter program to develop and evaluate batteries of in vitro tests for acute and chronic systematic toxicity, ATLA, 27 (1999), pp. 339–349
Björn Ekwall Memorial Foundation (BEMF)
The foundation was established in 2001 by the Scandinavian Society for Cell Toxicology (SSCT) in memory of Björn Ekwall. The foundation rewards Björn Ekwall Memorial Award (BEMA) to the scientist from around the world each year for excellent work in cell toxicology contributing towards the replacement of animal experiments by alternative toxicity tests and approaches.
Recipients of Björn Ekwall Memorial Award (BEMA)
So far, the following scientists have received the BEMA.
References
Swedish scientists
1940 births
2000 deaths
Toxicologists
20th-century Swedish biologists
Uppsala University alumni
People from Uppsala | Björn Ekwall | [
"Environmental_science"
] | 642 | [
"Toxicologists",
"Toxicology"
] |
70,764,591 | https://en.wikipedia.org/wiki/Enisamium%20iodide | Enisamium iodide is a derivative of isonicotinic acid. Based on its systematic chemical name of N-benzyl-1-methylpyridin-1-ium-4-carboxamide iodide, the shortened name carbabenzpiride is sometimes used. Enisamium iodide is a registered antiviral drug sold in Ukraine, Kazakhstan, Mongolia, Belarus, and other Eastern European countries under the trade names Amizon, Amizon Max, Amizonchik.
In 2019, the World Health Organization assigned enisamium iodide ATC code – J05AX17 (Antivirals for systemic use of direct action) and included it in the ATC / DDD index.
History
The compound enisamium iodide was first synthesized by scientists of the Institute of Pharmacology and Toxicology of the National Academy of Medical Sciences of Ukraine. In 1997, enisamium iodide was registered as a non-narcotic analgesic and antipyretic. However, it is no longer used for these indications. Amizon is marketed as an antiviral drug for the treatment and prevention of influenza and SARS.
In 2005, Doctor of Medical Sciences, Professor, and a corresponding member of the National Academy of Sciences and the National Academy of Medical Sciences of Ukraine, Frolov was the first to demonstrate the antiviral activity of enisamium iodide in in vitro experiments.
Recent studies have shown that the antiviral effect of enisamium is due to inhibition of viral RNA polymerase of influenza virus.
Since 2008, the non-clinical program, which included a set of pharmacological, pharmacokinetic and toxicological studies, has been performed in several research institutes and laboratories in Germany, the United Kingdom, the Czech Republic, the Netherlands, Switzerland and the United States.
Pharmacological properties
Mechanism of action
The antiviral activity of enisamium iodide is associated with inhibition of influenza virus RNA polymerase. Enisamium iodide effectively inhibited SARS-CoV-2 virus replication in vitro in Caco-2 cells.
Pharmacodynamics
Enisamium has antiviral activity against various strains of influenza A (H1N1, H3N2, H5N1, H7N9), influenza B virus, respiratory syncytial virus, as well as strains of alpha-coronavirus NL-63 and beta-coronavirus SARS-CoV-2, etc. In vitro studies using influenza virus-infected normal human bronchial epithelial cells conducted at the Illinois Institute of Technology Research Institute (IITRI), Chicago, USA, showed a decrease in viral titers due to incubation with enisamium iodide (24 FAV00A). year on 3 log (1000 times). In addition, the polymerase chain reaction with reverse transcription revealed suppression of the expression of the M-gene of influenza virus by almost 2 orders of magnitude.
Medical use
Amizon tablets are indicated for the treatment and prevention of influenza and acute respiratory viral infections. Amizon Max and Amizonchik syrup according to the instructions for medicines are intended for the treatment of influenza and SARS. Amizon Max is also used to treat COVID-19 of moderate severity in combination with basic therapy.
Clinical efficacy and safety
In 2010, the third phase of clinical trials on the basis of FBDU "Research Institute of Influenza" of the Ministry of Health of the Russian Federation (St. Petersburg, Russia) was completed with 100 patients (60 patients with influenza and SARS received enisamium iodide, 40 – placebo).
In the enisamium iodide group, the mean duration of fever was shown to be 2.7 days, and in the placebo group, 3.8 days. Thus, as a result of taking enisamium iodide, the duration of fever was reduced by an average of 1.1 days. When assessing well-being, a significant improvement on the 3rd day of treatment was noted by 43.3% of patients in the main group and 15% in the control group (p <0.001). On day 7 of treatment, almost all patients (59 out of 60) who received enisamium iodide returned to their usual way of life, while 37.5% of those who took placebo continued to feel unwell and had not yet returned to normal. work and leisure.
Enisamium was more effective when treatment was started earlier.
From May 2020 to March 2021, a batotocent clinical placebo-controlled, double-blind, randomized trial of enisamium iodide (Amizon Max) in patients with moderate to severe COVID-19 was conducted at 14 health care facilities in Ukraine. receiving inpatient treatment.<
The results of the clinical trial allowed to include in the instructions for medical use of the drug Amizon Max new indications for use, in particular - the treatment of COVID-19 moderate severity in combination with basic therapy.
References
Further reading
Drugs in Ukraine
Drugs
Quaternary ammonium compounds
Amides
Anilides | Enisamium iodide | [
"Chemistry"
] | 1,068 | [
"Pharmacology",
"Products of chemical industry",
"Functional groups",
"Chemicals in medicine",
"Amides",
"Drugs"
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70,766,818 | https://en.wikipedia.org/wiki/Slow%20violence | Slow violence is violence which occurs gradually and is not necessarily visible. Slow violence is incremental and is dynamic across time, in contrast with a conception of general violence as an event or action that is immediate, explosive and spectacular. Outcomes of slow violence include environmental degradation, long-term pollution and climate change. Slow violence is also closely linked to many instances of environmental racism.
The origins of the concept of slow violence can be traced back to the 1960s with the introduction of the idea of structural violence. In 1969, Johan Galtung conceived of structural violence. Some views include that structural violence and slow violence are closely linked, as structural inequality can morph into forms of slow violence. However, slow violence is thought to be different from structural violence, as slow violence occurs over a period of many years or generations.
The term slow violence itself was coined by Rob Nixon in his 2011 book Slow Violence and the Environmentalism of the Poor. Nixon defines slow violence as "a violence that occurs gradually and out of sight, a violence of delayed destruction that is dispersed across time and space, an attritional violence that is typically not viewed as violence at all". Rob Nixon states that people lacking resources or people who are living in poverty are the main casualties of slow violence, as it is "built on the bedrock of social inequality". Use of the term has since transitioned to involve applications outside of environmental concerns.
Interpretations of slow violence are varied. Thom Davies challenges the idea that slow violence is 'out of sight', but that instead it could be out of sight to a particular person or people. He contrasts an immobile and fixed nature of structural violence with his and Nixon's ideas of a geographically and temporally dynamic movement of slow violence over time. Davies also states that a lack of understandings of process, interactions, and effects can result in slow violence. Ahman produces work that contributes to the shared idea that both slow violence and its responses are characterized by manipulations of time. Shannon O'Lear provides another definition stating that slow violence is indirect and latent, and that "it can result from epistemic and political dominance of particular narratives or understandings."
Digital slow violence is characterized by the gradual and often unnoticed adverse effects in the digital realm, such as extended online harassment and unauthorized sharing of personal information, which collectively can affect individuals' well-being over extended periods.
Types of slow violence
The definition and use of slow violence has evolved throughout time to include the following examples:
Slow violence in energy
Petrochemical infrastructure
Communities surrounded by petrochemical infrastructure endure toxic pollution, which is defined by Thom Davies as a type of violence. However, this type of slow violence is not entirely invisible to the people they impact. People subject to slow violence gradually witness the daily impacts of that violence. Davies records instances of slow violence caused by petrochemical infrastructure in Freetown, Louisiana, where 136 petrochemical plants reside. This instance of slow violence is a form of environmental racism, as it is occurring on land with a population of 95% African Americans.
Fairfield Renewable Energy Project
In 2009, a trash incinerator called the Fairfield Renewable Energy Project was set to be constructed in Maryland's Curtis Bay neighborhood. The energy the incinerator generated from burning waste and garbage would power other neighborhoods located in Baltimore and was presented as a renewable energy source. At the time, state officials were considering reclassifying incineration as a Tier 1 renewable energy source. Curtis Bay community members, high school students, activists, and scholar Chloe Ahmann argued that the project would also build upon the preexisting slow violence the neighborhood was facing in the form of further pollution. Curtis Bay is surrounded by various forms of industry such as parts of the petrochemical, steel, fertilizer, oil, and chemical industries, as well as a medical waste incinerator and various dumps. The way the impacts of these industries and other projects have accumulated over time is an example of slow violence. As described by Ahmann, health conditions – such as gastroschisis, cancers, and fatal cases of asthma – have appeared over multiple generations, all of which are concentrated in this neighborhood. Ahmann also points out how residents’ mindsets can illustrate the impact of slow violence. Many remarked on a feeling of normalcy about these conditions – that this was how it had always been. Others expressed frustrations about the inability to concretely connect current health conditions to their former occupations or long residency in the neighborhood that exposed them to hazards or unhealthy conditions.
The Fairfield Renewable Energy Project was met with resistance and eventually stopped. It also brought attention to other acts of slow violence stemming from the industrial structure of the Curtis Bay neighborhood.
Jharia coalfields
The Jharia coalfields are the location of India’s biggest and longest running coal mines. They account for a significant percentage of the country’s coal production.
Coal mining is an extractive industry because it is a process that removes natural resources from nature. Extractive processes have been recognized by Nixon to create a specific type of tension that is characteristic of slow violence. For example, the workers that initially arrive to do the extractive labor and those that remain after and live through the longer-term impacts have different experiences. In the case of the Jharia coalfields, this is evident in both impacts on workers’ health and impacts on the surrounding environment. Both are examples of slow violence because, while they have harmful effects on the peoples and environments in the area, these effects are gradual. It is these collective effects that gradually accumulate which Nixon identifies as slow violence. In the case of Jharia miners or other laborers, their health is impacted by consistent coal fires that release harmful chemicals like “sulfur dioxide, nitrogen oxides, lead and methane” into the environment. The effects range from respiratory challenges that may develop into disorders and nervous system damage. Environmental impacts are also spread out over time. Before mining started, the areas were “thick forests…populated with tribal communities”. To create space for mining, these areas were deforested, and the tribal communities displaced. These communities also became “vulnerable to large-scale capitalist exploitation in the form of cheap causal labor”. The environmental slow violence that occurred in the area has appeared in the form of chemical changes in the soil and water, unpredictable land movement, underground fires, and physical landscape degradation. S. and Shah attribute this to “years of unscientific mining and lack of standard practices such as backfilling”.
The coal industry supports energy modernity, or “the improved conditions of social life enabled by energy transition from less efficient energy sources…to more efficient ones”. The physical and mental distance from urban environments that the Jharia coalfields embody is an example of the ways that the impacts of energy are often invisible, hidden from the consumer or actor. While energy is consumed, seemingly inconsequentially, the environment and the health of miners slowly deteriorates.
Indigenous reserves
Slow violence has been recorded as affecting the Indigenous peoples that once inhabited Yuquot, British Columbia. Indigenous peoples were relocated from Yuquot to Ahaminaquus Indian Reserve 12, in Vancouver Island by the Canadian government in the late 1960s The Department of Indian Affairs leased 30 acres of this land to Tasis Company who opened a Kraft pulp mill in 1968, on the same day of the closure of the Yuquot day school. The mill produced noise, air and water pollution, while also resulting in a road constructed over Muchalaht graves. Over time, the Department of Indian Affairs required the Indigenous peoples to give up their rights to reside on Ahaminaquus land, as well as their right to pursue health related claims from their residency. The Indigenous peoples claimed to have lost cultural opportunities and practices as a direct result of the pollution, as it was degrading the land. Paige Raibmon states that these circumstances represent modern-day colonialism.
Policing
Contemporary policing has been reported as a form of slow violence against marginalized communities. Rory Kramer and Brianna Remster state that police impose slow violence on Black and Brown Americans through racial and class-based harms inflicted by the state. Slow violence results in cultural trauma for people of colour, which is defined as "when members of a collective feel they have been subjected to a horrendous event that leaves indelible marks upon their group consciousness, marking their memories forever and changing their future in fundamental and irrevocable ways."
Women and slow violence
Women globally face instances of slow violence. Amy Piedalue who conducted research in Hyderabad, India states that the women "live and work in spaces of dispossession and marginalization", and that the slow violence they endure is specific to the dense urban settlement they exist in. They experience mobility constraints, due to economic resources being limited, as well as public safety concerns. Piedalue also reports that slow violence in these urban settlements is seen through illness, unemployment, hunger, the decaying of sanitation and infrastructures, and limited access to education.
Gender-based violence has also been experienced in the context of layered disasters over time in Bangladesh. Rezwana highlights the multi-dimensional and extended temporality of slow violence as an important facet in disaster response and recovery.
Urban housing and land ownership
Slow violence has been used in discussion of urban housing crises, such as in Chahim's work in Mexico City. Throughout the time of Chahim's fieldwork, it was identified that the flooding of drainage systems were engineered to consistently impact the poorer areas of Mexico City while preserving higher class areas. Normalization of this occurrence over time within the poorer population contributed to a slow temporality, and the violence Chahim identified was in the form of consistent and inequitably disruption of lives and property without consent.
Feminist geographer Rachel Pain brought Nixon's concept into conversation with feminist readings of trauma to document how housing dispossession in the UK has also been an example of slow violence. Pain describes how globalization, gentrification and displacement, and other psychological effects of violence experienced over time and across generations lead to "chronic urban trauma". Pain has also extended Nixon's framework to highlight how such dispossession targets particular categories of people and places, adding critical feminist and anti-racist perspectives that were missing from Nixon's framework.
Slow violence has also been mentioned in concerns related to rhino poaching in Mozambique's Limpopo National Park. A call for such violence to be addressed in order to better mobilize a response was featured in a literary work. This work also discussed the region's experience of slow violence through conservation-related resettlement.
Colonialism
Slow violence through time and space is also said to be enacted through means of colonialism such as that of the Hawaiian overthrow by the U.S.
Authors on the subject of the Overthrow of the Hawaiian Kingdom identify slow violence in the context of slow invasion. This can include physical invasion but also invasion through epidemics, missionaries, plantations, militarism, tourism, unemployment, displacement, health problems, and gendered representation/oppression. Tengan claims that the stereotypical Hula Girl's gendered and sexualized nature both attracts tourism and hinders movements towards honoring traditional Hawaiian masculinities, and is an example of slow invasion of gendered representation in his 2014 work. Hawai'ian sovereignty has continued to be denied despite lawsuits regarding the matter.
Asylum seekers
Slow violence has also been related to immigration and asylum seeking processes. Violence enacted through abandonment by political frameworks as an outcome of the mechanisms of power relations is said to leave gradual long-term effects on the mental and physical health of asylum seekers. This involves a denial of the basic rights of humans as outlined by Agamben. This is said to qualify both the experience of slow violence and spurring the response of slow resistance.
Resistance to slow violence
Communities impacted by slow violence can resist this violence through counter-violent agendas, sometimes referred to as slow resistance.
Slow resistance
Slow resistance has been referenced as a response to slow violence, and can include resistance through protests, exercising performative rights, everyday resistance, hunger strikes, and more. Slow resistance can function as an "umbrella concept" that can include many forms of non-organized and organized forms of resistance. Global resistance against racial violence amidst the effects of the COVID-19 pandemic is a specific characterization of slow resistance as discussed by Pain.
Resistance itself has been classically analyzed by Foucault as being able to be expected where there is power and forms of violence. In contrast, from the perspective of Abu-Luhgod, it is easier to first spot resistance than to begin with identifying power. Identifying these forms of resistance, and in particular slow resistance, may assist in better identifying slow violence. Resistance has also been identified as a conscious act through choice of language discourse by the disempowered, but this perspective has its critiques of being limited.
Environmental resistance
Resistance towards slow violence often occurs in the form of environmentalism. These movements when countering slow violence may refuse the distinction between environmental and social justice. For example, in Kenya, the Green Belt Movement mobilize the gradual violence of deforestation and soil erosion. The Movement was positioned at the crossroads between environmental and women's rights, because the environmental degradation being countered has common origins with the dispossession of economic resources during the colonial regime, especially towards women.
Manipulations of time
Slow nonviolence has been suggested as a method of counter-violence by Piedalue who theorizes it, "as focused on long-term incremental change, which not only responds to violence but is also productive of alternative visions and modalities of nonviolent social relationships and interdependencies". Piedalue states that slow nonviolence is a method of undoing future and past violence. Slow nonviolence approaches include protests, engagement from media sources, and public events, but as Piedalue states it operates mostly "through the intimacies of everyday life" and spaces such as homes or schools.
Other studies of slow violence, such as Chloe Ahmann’s report on the Fairfield Renewable Energy Project, highlight other ways time can be used to create resistance to slow violence. She describes three types: incrementality, deferral or delay, and concentration. Incrementality most closely mirrors slow violence by working to gradually create resistance, increasing its effects over time. An example of this could be small victories in legislative battles, stalling or delaying projects momentarily, or slowly building public awareness to create a growing community of resistance. This strategy accumulates and creates counter-systems as it progresses. Deferral or delay often takes the form of enforcement of regulations or legislative action. These strategies use the timelines of judicial or legislative processes – which are often lengthy – as a barrier that limits the ability of those creating or contributing to slow violence. This then eases the pressure of time constraints for activists or protestors. Finally, concentration utilizes deadlines and quick action to pressure actors and force a decision to be made.
Environmental photography
Environmental photography is a valuable tool for resisting, or uncovering the effects of, slow violence. Capturing the impacts of slow violence can interrupt the invisibility of long timelines over which it acts or unhide it from view if it is physically obscured or distant. Photographs of the Jharia coalfields, as described by Meenakshi S. and Krupa Shah, contrast the “slowly unfolding horrors of slow violence” with the “quicker sensation of the visual medium”. In cases like these where slow violence is occurring in locations set far aside from public view, photography can bridge this gap. Photography not only captures the effects of slow violence in the moment, but through exposure to the realities of these extractive energy industries, it can actively resist slow violence by bringing these affects to a wider audience.
Digital slow violence
Overview
Rachel Brydolf-Horwitz investigates digital slow violence, which expands on Rob Nixon's concept of slow violence. Traditional notions of violence emphasize quick, explosive, and visually stunning acts. Slow violence, on the other hand, is distinguished by its gradual and cumulative nature, which frequently goes unrecognized due to its temporal complexity and lack of instant, dramatic exposure. In the context of digital technologies, this kind of violence is further disguised by the complicated and ever-changing structure of the digital environment, which covers not just the tools themselves but also the social behaviors and assumptions they impact.
In her research, Brydolf-Horwitz utilizes the example of Rehtaeh Parsons of Nova Scotia to demonstrate how digital technology may allow slow violence through repeated verbal and textual attacks, as well as the nonconsensual sharing of personal photos. The phrase "cyberbullying" is commonly used to characterize such behaviors, although it can sometimes hide the deeper, more long-term harm perpetrated on people. By offering terminology to express these experiences, Brydolf-Horwitz emphasizes the need of recognizing and treating the unseen and difficult-to-address components of digital slow violence. Recognizing targets is vital for accountability and providing assistance and resources.
Digital slow violence emphasizes the need for a more comprehensive knowledge of how violence emerges in the digital era. It prompts to evaluate the long-term consequences of digital connections and how they might impair people's well-being.
A case study from Nova Scotia
The story of Rehtaeh Parsons from Nova Scotia exemplifies the concept of digital slow violence, as explored by Rachel Brydolf-Horwitz in "Embodied and Entangled: Slow Violence and Harm via Digital Technologies." This case highlights the serious ramifications of using modern technology as instruments for harassment and abuse, which can have negative effects. In 2011, the suicides of three young women in Nova Scotia, including Parsons, pushed cyberbullying to the forefront, leading the formation of a government Task Force on Bullying and Cyberbullying. Digital technology played a critical role in magnifying the abuse experienced by these individuals, prompting a public uproar and government action.The example of Parsons' experience emphasizes the mix of sexual assault and cyberbullying. After attacking the victim at a party, the perpetrators widely shared a photograph of the incident, sparking an aggressive and unrelenting campaign of internet harassment against Parsons. This instance clearly depicts the notion of gradual violence through digital means, in which the injury is sustained over time.
Digital activism
In the digital age, social media platforms have become pivotal in highlighting environmental issues and mobilizing collective action. A compelling example of this is the response to the red tide event in Florida, which was not initially covered by traditional news outlets. Through the power of social media, over 5.8 million viewers were exposed to the environmental disaster via a TikTok video created by Paul Cuffaro, showcasing the devastating fish kills. This incident underscores the potential of digital platforms to bring attention to environmental catastrophes that might otherwise remain unnoticed.
Furthermore, the event's massive involvement on social media, notably on TikTok, where the hashtag "Red Tide" received over 27.3 million views, demonstrates the importance of digital activism in environmental campaigning. This instance highlights how social media not only allows for the speedy transmission of essential environmental information, but also empowers individuals to contribute to a greater knowledge and understanding of environmental concerns. The shift in media attention to the red tide occurrence, driven by user-generated material, demonstrates the dynamic capacity of internet communities to influence public discourse and perhaps shape legislative responses to environmental concerns.
Digital challenges and surveillance capitalism
In the realm of digital technology, surveillance capitalism represents a significant challenge, particularly through the mechanism of online behavioral advertising (OBA). This form of advertising, which tracks an individual's online activities to deliver personalized ads, has been identified as a source of "slow violence" against users. This section delves into the various ways OBA inflicts harm, drawing on findings from a study that categorized the negative impacts of OBA into four broad areas: psychological distress, loss of autonomy, behavior constriction, and algorithmic marginalization.
Psychological distress: Users typically express uneasiness and concern about the precision and intrusiveness of targeted marketing. This emotional disturbance originates from the intrusive nature of OBA, where users believe their privacy is continuously invaded, resulting to a state of perpetual vigilance and anxiety about what is being observed and inferred about their life.
Loss of autonomy: Surveillance capitalism, through OBA, undermines user autonomy by providing the illusion of choice. In fact, user behavior is extensively affected and formed by underlying algorithms that anticipate and manipulate user activities for commercial advantage. This manipulation limits actual free choice, making consumers feel vulnerable and controlled.
Normalization of discomfort: The pervasive nature of targeted ads leads to a normalization of invasive data practices, where users, despite their discomfort, come to accept these practices as an unavoidable aspect of digital life. This resignation to surveillance capitalism diminishes user dignity and perpetuates a cycle of exploitation.
Legal and design considerations: Addressing the harms of OBA requires a dual approach: legal recognition of privacy harms as tangible injuries and a shift in the design philosophy of digital platforms. Moving beyond optimizing platforms for advertising efficiency to prioritizing user control and privacy can help mitigate the slow violence inflicted by surveillance capitalism.
References
Further reading
Farmer, Paul. 2004. “Anthropology of Structural Violence.” Current Anthropology 45(3): 305-325
Violence | Slow violence | [
"Biology"
] | 4,408 | [
"Behavior",
"Aggression",
"Human behavior",
"Violence"
] |
70,767,357 | https://en.wikipedia.org/wiki/Daedalea%20circularis | Daedalea circularis is a species of mushroom in the order Polyporales.
References
Fomitopsidaceae
Fungi described in 2013
Fungi of China
Taxa named by Bao-Kai Cui
Fungus species | Daedalea circularis | [
"Biology"
] | 42 | [
"Fungi",
"Fungus species"
] |
70,767,363 | https://en.wikipedia.org/wiki/Full%20BASIC | Full BASIC, sometimes known as Standard BASIC or ANSI BASIC, is an international standard defining a dialect of the BASIC programming language. It was developed by the American National Standards Institute (ANSI) X3.60 group in partnership with the European ECMA. It describes an advanced version of BASIC with many features including structured programming, matrix math, input/output for file handling, and many other options.
ANSI's BASIC standardization was a two-stage process. The first, carried out as Minimal BASIC starting in 1974, was an effort to clearly define and standardize the original Dartmouth BASIC language so it could be correctly implemented on different platforms. After its release in late 1977, attention turned to Full BASIC which would be based on the more powerful Structured BASIC being developed at Dartmouth College. The complexity of the system and the many additions promoted by members of the standards committee led to the effort bogging down and the first draft standard was not ready until 1986, four years late.
The standard was ratified on 26 June 1986 as ECMA-116 and January 1987 as ANSI X3.113-1987. It was completely ignored; the microcomputer revolution had occurred while the specification was being argued over, and by the early-1980s Microsoft BASIC running on tens of millions of home computers had already come and gone. Watching the process drag on, the Dartmouth participants left to produce True BASIC based on parts of the standard, but this saw little use. De facto standards like Microsoft's dominated the market and formed the basis for newer languages like Microsoft Visual Basic which incorporated similar concepts.
History
Minimal BASIC
The introduction of Dartmouth BASIC in 1964 combined a number of emerging concepts in the computer field, including timesharing and direct interaction with the user, known at the time as a "conversational interface". General Electric, who supplied the GE 235 mainframe computer it ran on, used a modified version of Dartmouth's system to start a service bureau which would eventually evolve into the GEnie online service. Many other companies, Tymshare and CompuServe notable among them, quickly introduced hosted BASIC services of their own, following the Dartmouth model.
In 1968, Hewlett-Packard (HP) introduced the HP 2000 series minicomputers, which offered the same features of the earlier mainframe systems in a rack-mount system that could be configured in a complete form for around $100,000 (). Their HP Time-Shared BASIC had a number of differences from Dartmouth, and these were soon copied by other mini vendors like Data General. One holdout was Digital Equipment Corporation (DEC), who did not introduce a BASIC of their own design until 1972. This version, BASIC-PLUS was different from either the HP or Dartmouth dialects. By the early 1970s where were three major dialects and dozens of minor variations being used in the market.
In January 1974 a new group formed under the ANSI umbrella to define a single standard BASIC. The Dartmouth team formed a core part of the group. Dartmouth was working on a greatly expanded version of BASIC known as Structured BASIC (SBASIC) which became the basis for ANSI. At the time, few other dialects supported its many new features. The group decided that a complete standard based on SBASIC would take some time to agree on, so the ANSI BASIC effort was split into two milestones. The first, Minimal BASIC, would produce a standard that included only the most basic features that would be required of any implementation. Even long-supported features from Dartmouth like matrix math would be left out. The draft standard for Minimal BASIC was released in January 1976, the final draft in July 1977, and it was ratified that December. Arthur Luehrmann, a physicist from Dartmouth College who was a proponent of BASIC and part of the ANSI group later stated:
"X3J2's first few years were spent (in hindsight, some might say 'wasted') on standardizing what amounts to the original 1964 Dartmouth Basic... Minimal Basic was more a toy than an actual language."
Full BASIC
The group then turned their attention to Full BASIC. By this time the microcomputer revolution was in full flight, and millions of machines running Microsoft BASIC or a similar BASIC were entering the market. In spite of this, none of the participants were microcomputer vendors or suppliers. Instead, the participants remained mainframe vendors like IBM, Control Data and General Electric, minicomputer vendors like Digital Equipment Corporation (DEC), Data General and Wang Laboratories, and other very large companies like 3M, American Express and Kodak.
The effort immediately ran afoul of the second-system effect as every member began to add their own list of "must have" features. Some wanted the language to continue the tradition of being aimed at educational uses running on small machines and desired a simple language with only rudimentary file support and similar features. Others were mainframe users that wanted to support loadable modular programs and other expansive programming features to compete with languages like COBOL or FORTRAN while offering better string manipulation. A third group was primarily interested in business applications, especially European users where BASIC had become a primary business language, and they demanded the system include extensive file handling and decimal math that did not suffer from rounding problems.
John G. Kemeny and Thomas E. Kurtz, the original designers of BASIC and members of the ANSI group, were critical of the process. In a 1982 article, Kurtz wrote about how even seemingly small issues had turned into major controversies. He used the example of the statement. When arrays were first added to BASIC, they started at index 1, such that made an array with three slots, 1, 2 and 3. In some cases, an index 0 is more natural, so was added in later versions of the Dartmouth code so the same definition would have four slots, 0 to 3. During Minimal, there was continual debate about what the default base should be, and 0 was finally selected. Five years later, during the Full efforts, it was decided that arrays could define any lower bound using new syntax, . This eliminated the demand for and the decision was made to change the default to 1 again.
Initially, the X3.60 group was targeting a summer 1982 date for the first technical review copy, which would be sent to the ANSI X3 committee in the fall. During this period the proposed standard would be sent out, and comments from the public would be accepted. The final draft would be sent back to X3 in 1983 for ratification that year. This proved rather optimistic. The first draft was not released until January 1985 and the final draft in 1986 for ratification in January 1987. During this time, the standard grew so large that it was ultimately split into a core module and five optional add-ons, which included complex file handling, real-time computing support, fixed decimal math, optional editing commands and even a platform-independent graphics module.
The result was criticized during the public comment period. One reviewer noted it had grown so large that "the resulting language rivals any current programming language in complexity" and that "conforming to the entire standard would compare with the most substantial compiler projects ever attempted". It goes on to describe, for instance, how there are no less than five different ways to describe a subroutine, three to define a string's maximum length and two ways to define an array. Referring to the issue of array bounds, it is noted that the committee agreed the adopted solution was "intolerable" and made plans to fix it "later".
There is no evidence that any of the participants actually built a conforming version after the release of the standard and any mention of ongoing effort promptly disappears. From 1987, the only mentions of the standard are that it exists and that True BASIC encompassed some of its features. Additionally, with millions of micros running some variation of MS's de facto standard by this point, the new ANSI standard was seen as the non-standard solution. Much of the original success of BASIC on the micro platforms was that it allowed programs to be typed in from printed source code, but by the mid-1980s this had been replaced by shrinkwrap applications and the need for BASIC as a distribution system had faded. On the large-systems side, the original use as a teaching language was being increasingly replaced by Pascal, as the external problems BASIC aimed to address, like interactivity and online editing, were now available in most systems.
True BASIC
The standards process was so slow that even the author of Structured BASIC eventually gave up on it. Stephen Garland was asked to prepare a series of College Board tests for high school students, and wrote them in Pascal instead. This was somewhat controversial given that many computers in wide use, like the Commodore 64 and TRS-80 did not have a full implementation of Pascal. Luehrmann, was critical of the effort, suggesting a more general course that would be applicable to more students.
It became clear to the Dartmouth participants in the ANSI group that the effort had no hope of being completed in any reasonable time period. They left the effort and started a new company to bring their version of the language to market as True BASIC. True BASIC combined many of the features of the core standard but also made a number of changes of its own. Among the most notable was that line numbering was now optional. The language was not well received, with many reviews expressing the same concerns about feature bloat that had been raised about the Full BASIC standard. Jerry Pournelle derided it as "madness" and John Dvorak dismissed it as "sad" and "doomed to failure."
Description
Program editing
Like previous versions of BASIC, Full BASIC was designed to work in a line editor environment and thus uses line numbers to indicate individual or ranges of lines to be edited or removed. Line numbers could range from 1 to 50,000, in contrast to Minimal which was 0 through 9999. This meant that valid Minimal programs using line 0 were invalid in Full. Logical lines were at least 132 characters long. Logical lines could be extended across several physical lines using the "continuation character", the ampersand. Unfortunately, the ampersand was also selected as the string concatenation operator, which complicated the parser.
Additional editing commands included and , which by this time were common on newer microcomputer dialects. A new concept was , which copied a range of lines into a new file and deleted them from the original program, allowing them to be extracted to a subprogram. These could then be invoked using the command. could also include an optional followed by a list of parameters, in which case it was expected to return a value in a variable with the same name as the program (see "Structure", below).
Basic functionality
Many of the commonly used keywords found in Minimal or other dialects remained; , , and for instance. There were numerous minor changes to these commands. For instance, at edit time keywords can be typed in upper or lower case, or any mixture. As was the case in the past, they were normally displayed in uppercase, while a new convention was to use snake case for multi-character variable names.
Dartmouth BASIC introduced the statement for in-line comments and this was universally supported in other dialects. Many dialects also added a short-form, most commonly using the single-quote, , as seen in Microsoft BASIC. For Full, they selected the exclamation mark, for this role, although there appears to be no reason not to use the single quote as it is not otherwise used - strings do not allow single-quote delimiters for instance. A more controversial change was that the keyword was now required for all assignments in order to make the parsing simpler, whereas in every other dialect was optional. This included Minimal, so any Minimal code using this short-cut was incompatible with Full.
On top of the relatively small set of 23 keywords and 11 functions from Minimal, Full added dozens of its own, for a total of 176 keywords (defining 161 separate concepts), 38 mathematical functions and 14 string functions if all extensions were included. A simple list of the keywords, laid out in three columns, fills two pages in the standards document.
Structure
The major difference between Full and Minimal was the addition of block-oriented structured programming constructs. In Minimal, and most BASIC interpreters, the program logically consisted of independent lines of code and one could start execution at any point by ing any line number. The only exception to this rule was the loop, where all of the lines from the FOR to NEXT were logically considered to be a single block of code. Branching into or out of a FOR block would result in odd behaviour, typically implementation dependant but generally some form of error like "NEXT WITHOUT FOR".
In Full, branching into a FOR...NEXT block is not allowed, nor is branching out without using the statement. Implementations were supposed to check for such statements and disallow them, for instance, finding cases where to code ed into a loop. Checking for such code is difficult in an interpreter which normally examines the program line-by-line; checking for branches into a block from other code in the program would normally require whole-program parsing like a compiler.
In Full, several existing keywords were extended, and others added, to provide additional block structures. Notable was the multi-line , which allowed multiple lines of code to run if the condition was met or failed. was added to make decision trees, which formerly would have been implemented using the or multiple s to select a line to run. loops remained as they were in Minimal, but a new was added with top tested and bottom tested varieties. All loops could now be safely exited using the and commands.
On top of these changes to the block structures, Full also added keywords for defining procedures, functions and program blocks. Programs as a whole were now opened with the optional keyword followed by a program name, and ended, as before, with . Routines could be constructed with and called using . Multi-line functions were created with and did not declare a return type as that was part of the name - string function names ended with the dollar sign. The return value was provided by setting a variable to the same name as the function, for instance, a function named "DOIT" would contain a line like . Functions could call other functions and themselves, meaning that the language was naturally recursive. Full also retained the earlier style of one-line function definitions using the keyword, but removed the requirement for the function name to start with "FN". For instance, .
In previous BASICs, there was no concept of scope and all variables were global. This is not adequate for the construction of large modular programs, as one section of code may have been written using common variable names like and might change the value of that variable. As the variable is global, it retains the modified value when it returns to the original code. A key concept of structured programming is the local variable, which holds its value separate from other variables with the same name in other locations in the composite program. As BASIC did not have the concept of scope, many programs relied on the global behaviour and used variables to pass information in and out of subroutines. To allow both concepts in the new language, Full BASIC added the keyword that could be added to a function or subroutine and made any variables within in local. As BASIC programs generally placed subroutines at the end of the program's source code, the keyword was added to provide forward declarations.
Data types and variables
Full BASIC introduced long variable names, finally breaking free of the single letter or letter-digit names of the past. It set the new limit at 31 characters. One minor downside to this change was that keywords had to have spaces between them, whereas most earlier versions allowed the spaces to be left out. This was because with single-letter names a line like can be parsed as "FORS", which can not possibly be a variable in a two-letter variety of BASIC. In Full, this would have to be typed because "FORS" is a valid variable name. As was the case in earlier BASICs, data types in Full were denoted by suffixes on the variable name. Minimal had avoided this issue by only having numeric variables, but Full included strings as well, denoted using the dollar-sign, for instance .
Full BASIC required decimal math for the default implementation of the floating point system. As this was not universally supported in hardware, especially on minis and micros, it also added the which indicates that math should be carried out using the system's default floating point implementation, whatever that may be. It can be returned to BCD mode with . This is in addition to the fixed-point math option, if installed. Numeric and string variables otherwise worked like those in other BASICs.
A new addition was the fixed-point math extension, which allowed variables to have specified accuracy. This was turned on using the command followed by an asterisk and a format specifier, for instance, would set all numeric variables to have 8 digits of accuracy and two decimal places. Such a declaration must be placed before any mathematics code in the rest of the program. Furthermore, any single variable could be individually defined using something like .
Most BASICs supported the construction of array variables using the keyword, for instance, defines two arrays, the single-dimension A and two-dimension (matrix) B. In Full BASIC, the lower bound of any array was normally 1, so in this case, the variable A has five "slots", numbered 1 though 5. Using above this declaration would add another slot at index 0. Full also added a new system to directly specify the lower and upper bounds using the keyword, for instance, which makes a one-dimensional 101-slot array. To further confuse matters, could also be used to create arrays; the same dimensions as the last example could be created with .
Mathematics, logic and matrices
The list of supported math operators included all of those from Minimal, , , , and . The new function returns the remainder of an integer division. The list of logical operators was expanded, , and had been removed from Minimal and now re-added, and the alternative forms of comparison operators were added, , and .
The list of primary built-in functions remained similar to previous versions of BASIC, including common examples like or . Trig functions were expanded to include , , , , and . The new function returned the angle between the origin and a given X,Y point. BASIC normally calculated angles in radians, but would convert all parameters and outputs to degrees, and the system exposed the function which was used in these conversions and elsewhere.
Dartmouth BASIC had introduced matrix operations relatively early in its evolution, and these were part of Full. These overload the existing math functions, so one can multiply two arrays using or multiply the contents of an array by a scalar if the B parameter is not an array. The system also adds several array-only functions, which includes o, ert and erminate, among others. The addition of matrix math also requires modification of existing keywords like and , which output or input multiple elements as needed to fill the array parameter.
Matrixes may be redimensioned as part of a by specifying the new bounds, like . The new dimensions must have a total number of elements equal or smaller than the original , so in this example if the original definition was , the input would cause an error.
Strings
Early versions of Dartmouth BASIC did not include string variables or manipulation, the only strings in a program were constants like . Version 4, of 1968, added string variables and a single method to manipulate them, , which converted strings to and from an array containing the ASCII values of the characters. For instance, would produce an array of values in A, where A(0) was 72, the decimal ASCII value for "H". This made string manipulation fairly difficult, for instance, to extract the "HELLO" from "HELLO, WORLD!", one would have to:
10 A$="HELLO, WORLD!"
20 DIM A(25), B(5)
30 CHANGE A$ TO A
40 FOR I=1 TO 5
50 B(I)=A(I)
60 NEXT I
70 CHANGE B TO B$
Many dialects of BASIC had added their own methods of performing more useful string manipulation to avoid such complication. For Full BASIC, the committee selected a variation on the concept introduced by HP, "string slicing". This concept treats the string as an array of characters and can access them using an array-like specification known as a "slice". To extract "HELLO" from "HELLO, WORLD" in Full, one would use . The concept is similar to that of , but this method produces results that are themselves strings, not numeric values, and thus one can to produce "HELLO". One significant difference between Full's approach and previous ones like HP is that it used a different syntax for the slicing, whereas the earlier systems used array syntax. For instance, in HP, the equivalent line is . As this is the same syntax as array accesses, HP (and similar) generally did not allow string arrays, whereas this was allowed in Full.
This approach should be contrasted with the solution selected by DEC, the use of functions that return new strings, , and . This was the solution picked up by Microsoft when they wrote their BASIC on the PDP-10. Converting between the two can be error prone, to perform the equivalent of , Full would use .
Input/Output
Another area of focus for Full BASIC was input/output (I/O). Minimal BASIC's only I/O was the and commands and the ability to hard-code data using the statements and it. Almost all practical dialects added and to create a "channel" that was then used to refer to that particular file or device.
now included an optional , followed by a string, a colon and then the input variables, for instance . By this time almost all BASICs included a similar feature without the word and using the existing print separator semicolon instead of colon, for instance in MS BASIC the same line would be . On top of this, Full also added the new and keywords: , which will continue execution after 30 seconds even if the user enters nothing, and will put the time it took, possibly the 30 seconds, into the variable T. For systems lacking a clock (which was not uncommon at the time), T would always return -1.
ing was similarly expanded with the optional statement, which had already appeared on a number of implementations. The was normally followed by a format string using number signs, asterisks and percent signs to mark decimal places. The format string could be placed in a string variable and then referred to, or an optional separate line containing a could be referred to by line number. Full also added new commands to set the printing area, and . The current values of these various settings (and others) could be returned using . For instance, followed by would set J to 30.
Full supported file operations with and and a channel number prefixed with a number sign, for instance, . Data can then be written using and or and the new . Additional file handling commands included and , and all of these commands had numerous options and modes. Much of this stemmed from the different types of physical devices that were still common in the late 1970s, magnetic tape, for instance, could only be accessed sequentially so the new standard offered options for or , etc. The list of options and their interactions and limitations covers many pages in the standard. For instance, it is possible to to a file of type, but not type, which required .
Exception handling and debugging
Like many BASICs of the era, Full added the command which would print out line numbers as the program executed. It could also redirect the printing of the line numbers to another device or file using , where #3 was a previously opened channel. It also added the and related statement, the latter of which would cause an exception if debugging had previously turned on. Debugging status was limited to a particular program, so it could be turned on in one program and off in a subprogram, for instance.
Additionally, Full added true exception handlers, based on the block. There were two ways to use this, if the code block started with the following code was executed as a block and any exception within it would cause it to jump to the section, which operates similar to an . It can also be used by defining a separate subroutine-like block using which would then be called by name using . The code could test which exception had occurred using the meta-variables or the , neither of which needed an . exited the error handler and returned to the line of the error, while could be used within the mainline code to ignore errors even within blocks.
Graphics
Around the same time that Full was being designed, a parallel effort was underway to define the Graphics Kernel System, or GKS. This was offered as one of the optional modules in Full. This added dozens of special keywords like and with syntax that did not match that of the other modules in the standard. For instance, the command turned on clipping to the current viewport such that items drawn outside its boundaries would not be visible; this took a string value instead of a boolean, . Several common image modification commands were added, , , and .
As images are often built up from common elements, Full added the new block structure, which is otherwise similar to a and invoked with rather than . The difference is that the output of a picture block can be modified with the modification using . For instance, if one defined a which produced a circle of radius one, a smaller circle could be drawn and moved to the side with .
Real-time
Full's real-time module added the concept of "parallel sections", through the keyword. These looked like subroutines (and pictures) but had a number of additional keywords that controlled their invocation. For instance, one could define code that would respond to an and then cause it to run by issuing a elsewhere in the code. The messages could invoke multiple handlers using the ports concept.
The system also allowed these blocks and objects to be connected to external code that would create these messages. One could, for instance, have code that waited on a device that periodically created text output, and then the appropriate handler would automatically be called when new text was available. Because the actual data from such devices tends to be multi-part, not something simple like a string or number, the real-time library also added the ability to define s that could then be read or written as an atomic unit. These were then read and written using the and commands, or if the data was , the otherwise similar and .
Although many real-time programs can be modelled as a system simply responding to external events, it is also common for the program itself to periodically post these events. For this, Full added the command and the associated which would pause execution for a given (a number of seconds) or (an explicit time-of-day) or until an was seen.
ECMA vs. ANSI
The ECMA and ANSI standards were not developed jointly but in parallel, though with overlapping committee membership. Conversely, the ISO working group for BASIC did not develop a standard of their own, instead planning to adopt either the ECMA or ANSI standard.
Independently of ANSI, the ECMA committee responsible for the BASIC standard split it in two: ECMA BASIC-1 and ECMA BASIC-2. BASIC-1 included some of the file manipulation system but lacked the exception handling, while BASIC-2 added the full suite of file commands, fixed decimal math and the exception handling system. Additionally, in BASIC-1 all fundamental keywords like were reserved words which simplified the parser, while in BASIC-2 they followed the ANSI pattern and could be used within user-created subroutines and functions.
The ISO working group had initially planned to use ECMA's standard. Faced with the problem of two different candidate standards, in September 1987 it was directed to develop a single international standard unifying the two. This was accomplished by specifying that compliance to either standard could be claimed as conformance to the ISO standard.
Notes
References
Citations
Bibliography
Further reading
External links
Decimal BASIC - a relatively complete implementation of Full BASIC and its graphics modules
BASIC programming language
American National Standards Institute standards
Ecma standards | Full BASIC | [
"Technology"
] | 5,851 | [
"American National Standards Institute standards",
"Computer standards",
"Ecma standards"
] |
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