id int64 39 79M | url stringlengths 31 227 | text stringlengths 6 334k | source stringlengths 1 150 ⌀ | categories listlengths 1 6 | token_count int64 3 71.8k | subcategories listlengths 0 30 |
|---|---|---|---|---|---|---|
62,549,516 | https://en.wikipedia.org/wiki/Tan%20Tin%20Wee | Tan Tin Wee (born 1962) is a Singaporean bioinformatician and university lecturer. He is an associate professor at the Department of Biochemistry at the National University of Singapore and Chief Executive of the National Supercomputing Center (NSCC) Singapore. As the inventor and founder of multilingual internationalized domain names (IDN) and a pioneer of the Internet, he was inducted into the Internet Society of 2012 along with the founding fathers of the Internet in the first Internet Hall of Fame. He is well known in Singapore and the region for his work on propagating and developing the Internet.
Education
Tan studied Biochemistry at the University of Cambridge from 1982 to 1985, after which he received the Master of Science in Molecular Biology and Biotechnology at University College London. He followed it up with a PhD in molecular biology on vaccines at University of Edinburgh in 1990.
Biography
Tan returned to Singapore in 1990 to develop TechNet, Singapore's first network for a nationwide research community. In 1994, he and his Chinese language team wrote a program that matches the code for each character and then merged the images into one larger image. This program was also extended to the Tamil language. Tan was responsible for several key internet milestones, including the first Gopher Server, the Singapore InfoWeb and the forerunner of the present National Web Homepage. Under his leadership, the Internet Research and Development Unit (IRDU), developed the first regional Java website and the first functional multilingual domain name system (iDNS).
In addition to his NUS position, Tan is also chair of the agency for the Computational Resource Center for Science, Technology and Research, which is equipping Singapore with supercomputing capabilities for the twenty-first century. Tan also pioneered the use of new technologies for online computer communication.
In November 2014, his team, along with Australian, Japanese and US universities, as well as industry partners Obsidian Strategics and Tata Communications, demonstrated the first high-speed InfiniBand connection between three continents on a platform called InfiniCortex.
In 2015, the National Supercomputing Center was set up and Tan became the Chief Executive.
Personal life
Tan is married to Karen Seow. They have a daughter and a son.
Awards
For his work, he received national and international recognition: the Singapore Youth Award for Excellence (1994), the Vaccine Research Trust Annual Award (1989), the Japanese Chamber of Commerce and Industry (JCCI) Education Award (1997 ), the ASEAN Achievement Award (1997) from the ASEAN Business Forum, the Life Insurance Association (LIA) Award for community work, the 7th Innovation Award of the Indian Cultural Festival (1998), the Achievement Award (1998), the gold medal of the World Congress for Medical Informatics MEDINFO'92 and he is a member of the International Who's Who of Professionals (1999) and a member of the exclusive World Technology Network (2001) as one of 450 leading scientists and entrepreneurs worldwide.
He has been featured in books such as Singapore's Scientific Pioneers as one of 25 pioneers and the Singapore Tamils 200, a book which was released in honour of those who contributed to the Indian community development.
He has served in the board of directors of Keppel Telecommunications and Transportation, and currently serves in the management board of Keppel Data Centre REIT listed in Singapore stock exchange.
He is also a proponent of environmentally green data centers at TED talks.
References
External links
NSCC MANAGEMENT – NSCC
Singapore Campus Party Biography
The Accidental Internet Pioneer
Singapore's supercomputer ambitions get a timely, much-needed boost
1962 births
Living people
Singaporean academics
Alumni of the University of Cambridge
Alumni of University College London
21st-century Singaporean biologists
Alumni of the University of Edinburgh Medical School
Bioinformaticians
Internet pioneers | Tan Tin Wee | [
"Biology"
] | 769 | [
"Bioinformatics",
"Bioinformaticians"
] |
66,249,438 | https://en.wikipedia.org/wiki/Berkeley%2087 | Berkeley 87 is an open cluster in a heavily obscured region of the Milky Way in Cygnus. The rare WO type Wolf–Rayet star WR 142 is a member of Berkeley 87.
This cluster contains HD 229059 which, as of August 2021, is the nearest known star to Earth with a bolometric luminosity greater than 1 million L☉.
See also
List of most massive stars
References
Open clusters
Cygnus (constellation)
Star-forming regions | Berkeley 87 | [
"Astronomy"
] | 97 | [
"Cygnus (constellation)",
"Constellations"
] |
66,249,878 | https://en.wikipedia.org/wiki/Arctic%20Wolf%20Networks | Arctic Wolf Networks is a cybersecurity company that provides security monitoring to detect and respond to cyber threats. The company monitors on-premises computers, networks and cloud-based information assets from malicious activity such as cybercrime, ransomware, and malicious software attacks.
History
Founded in 2012, Arctic Wolf focused on providing managed security services to small and mid-market organizations. The company was listed as a Gartner Cool Vendor in security for mid-sized enterprises in June 2018.
Acquisitions
In December 2018, Arctic Wolf announced the acquisition of the company RootSecure, and subsequently turned the RootSecure product offering into a vulnerability management service.
On February 1, 2022, Arctic Wolf acquired Tetra Defense.
In October 2023, Arctic Wolf acquired Revelstoke, a cybersecurity company.
Cylance was acquired from Blackberry Limited by Arctic Wolf in December 2024.
Funding
In March 2020, following a $60M D Round of funding, the company announced moving its headquarters from Sunnyvale, California to Eden Prairie, Minnesota in October 2020.
In October 2020, Arctic Wolf announced a $200M E Round of funding at a valuation of 1.3B$.
On July 19, 2021, Arctic Wolf secured $150M at Series F, tripling its valuation to $4.3B.
References
External links
Software companies established in 2012
Network management
Software companies of the United States
American companies established in 2012
Computer security companies
Information technology companies of the United States
Security companies of the United States | Arctic Wolf Networks | [
"Engineering"
] | 302 | [
"Computer networks engineering",
"Network management"
] |
66,250,693 | https://en.wikipedia.org/wiki/Andreas%20Papadopoulos%20%28politician%29 | Andreas Papadopoulos (1922-2009) was a Cypriot politician and engineer. He was Minister of Communications and Works in Cyprus from 16 August 1960 to 20 April 1966.
Life
Andreas Papadopoulos was born in Limasol in 1922. He was educated at Limmasol Greek Gymnasium and the School of Civil Engineers at Athens Technical University. After working as a civil engineer, he was appointed Minister of Communications and Works in Cyprus in 1960.
References
1922 births
2009 deaths
Greek Cypriots
Ministers of communications and works of Cyprus
Civil engineers
People from Limassol | Andreas Papadopoulos (politician) | [
"Engineering"
] | 111 | [
"Civil engineering",
"Civil engineers"
] |
66,250,770 | https://en.wikipedia.org/wiki/Kepler-429 | Kepler-429 (KIC 10001893) is a variable subdwarf B star in the constellation Lyra, about 5,900 light years away.
The brightness of Kepler-429 changes unpredictably by up to 0.13 magnitudes. It has been classified as a V361 Hydrae variable, but also as a V1093 Herculis variable, which typically has slower variations and a cooler temperature. Over 100 pulsation modes were identified with periods from 256 seconds to over three hours.
Planetary system
Kepler-429 has been reported to have three possible exoplanets, though their existence is questioned. They were detected by orbital brightness modulation.
See also
Kepler-70
References
B-type subdwarfs
Kepler objects of interest
Lyra | Kepler-429 | [
"Astronomy"
] | 163 | [
"Lyra",
"Constellations"
] |
66,251,126 | https://en.wikipedia.org/wiki/Spizellomyces%20punctatus | Spizellomyces punctatus is a chytrid fungus living in soil. It is a saprotrophic fungus that colonizes decaying plant material. Being an early diverging fungus, S. punctatus retains ancestral cellular features that are also found in animals and amoebae. Its pathogenic relatives, Batrachochytrium dendrobatidis and B. salamandrivorans, infect amphibians and cause global biodiversity loss. The pure culture of S. punctatus was first obtained by Koch (named Phlyctochytrium punctatum).
Genome
The genome of S. punctatus strain DAOM BR117 was sequenced under the Origins of Multicellularity project. Its genome size is about 24.13 Mb with a GC content of 47.6%. The genome has 9,424 predicted transcripts and 8,952 predicted protein-coding genes. The DDBJ/EMBL/GenBank accession number is ACOE00000000.
Genetic transformation
Agrobacterium-Mediated Transformation
Genetic transformation of S. punctatus zoospores by plant pathogen Agrobacterium tumefaciens EHA105 strain is successfully established. Several selection markers have been tested. The growth of S. punctatus is not inhibited by Geneticin (G418), Puromycin, and Phleomycin D10 (Zeocin) up to 800 mg/L. 200 mg/L Hygromycin and 800 mg/L Nourseothricin (CloNAT) completely inhibit S. punctatus growth. The scientists who develop this protocol use Hygromycin as the selection marker. S. punctatus HSP70 and H2B promoters drive sufficient gene expression for Hygromycin resistance and GFP expression tested in yeast. Controlled by stronger H2B promoter, however, GFP may not be successfully folded in S. punctatus. Other fluorescent proteins, including tdTomato, mClover3, mCitrine, and mCerulean3, are functional in S. punctatus.
Electroporation
A high-efficiency electroporation protocol for S.punctatus and two related chytrids species B. dendrobatidis and B. salamandrivorans has also been established. The optimal voltage for S. punctatus is 1000 V. The efficiency is about 95% using synchronized zoospores. Electroporation using unsynchronized zoospores can also reach more than 80% efficiency.
Life cycle
S.punctatus globular zoospores (3–5 mm) lacks a cell wall. The zoospores can swim with a motile cilium (20–24 mm) or crawl on surfaces by actin-filled pseudopods.
During encystment, the cilium is disassembled first via axoneme internalization. The initiation of this process is actin-dependent. The axoneme remains intact during internalization and the axonemal tubulin is degraded at least in part by the proteasome. The cell wall is formed after axoneme internalization. Five modes of axoneme internalization occur in S. punctatus: severing, reeling in retraction, lash-around retraction, ciliary compartment loss retraction, and vesicular retraction. First, severing is referred to as cilium detachment. Second, reeling in retraction is concurrent with or without cortical rotation and termed body-twist retraction and straight-in retraction, respectively. Third, during lash-around retraction, the cilium wraps around outside the zoospore with merging of ciliary membrane and plasma membrane. On 120 kPa fibronectin-coated hydrogels, this lash-around retraction occurs within a second. Fourth, for ciliary compartment loss retraction, ciliary membrane expansion is followed by merging of the ciliary compartment with the plasma membrane. Fifth, vesicular retraction is the creation of an axoneme loop bulge within the ciliary membrane before internalization.
After the cilium is retracted, the cyst germinates and generates a germ tube. The germ tube is then extended to form the rhizoidal system. Finally, the cyst develops into a sporangium, a reproductive structure, and mitosis begins. After five to eight times of synchronous mitosis, 32 – 256 zoospores form in the sporangium. Ciliogenesis probably occurs before cellularization. After cellularization, the zoospores escapes from the sporangium under suitable environmental condition.
The timing of the cell cycle has been quantified using the S.punctatus expressing H2B-TdTomato controlled by H2B promoter under microscopy. The retraction of the cilium and the start of encysting happen within one hour. The germ tube appears in one to three hours. The first mitosis happens in eight to twelve hours. It finishes five to eight times of synchronous mitosis in thirty hours. The average cell cycle takes about 150 minutes. Each nuclear division is completed in 1 minute.
Mitochondrial 5’ tRNA editing
This species is notable for having mitochondrial 5′ tRNA editing, a rare modification that is only known to also exist in the Amoebozoa species Acanthamoeba castellanii and Chytridiomycota species Harpochytrium94, Harpochytrium105, Monoblepharella15, and Hyaloraphidium curvatum. S. punctatus mitochondrial genome encodes eight tRNAs that recognize lysine, aspartic acid, tryptophan, methionine, tyrosine, glutamine, proline, and leucine codons. tRNALeu recognizes the UAG codon as leucine instead of the stop codon.
tRNAs form secondary structures that are composed of helical stems. Predicted from mtDNA, mismatches are found in the first three nucleotides of the eight tRNA acceptor stems. Sequencing of the mature mitochondrial tRNAs showed the replacement of pyrimidines or purines by purines (A to G, U to G, U to A, and C to A) that restore the base pairing. The editing sites are always restricted to the first three positions.
The mitochondrial 5’ tRNA editing of S.punctatus has been confirmed in vitro. Using mitochondrial extract, the 5’ mismatches of synthetic tRNA transcripts are removed and nucleotides are incorporated in a 3’ to 5’ direction by using the 3’ tRNA sequence as templates. The patterns of mitochondrial 5’ tRNA editing are similar to those found in A. castellanii.
Phytohormone receptor homologs
Ethylene and cytokinin receptors in plants are histidine kinases. Histidine kinases in fungi are hybrid histidine kinases due to the fusion of histidine kinase/histidine kinase-like ATPase catalytic domains (HK/HATPase domains) to the receiver domain. Ethylene and cytokinin receptor homologs are also found in several flagellated and unflagellated fungal genera, including Spizellomyces. In general, these two phytohormones are signaling molecules in plant biotic interactions. Ethylene and cytokinin receptors in early diversifying fungus may play important roles in colonizing land.
Opsins
Two opsin types exist: Type 1 opsins are used by prokaryotes and by some algae (as a component of channelrhodopsins) and fungi, whereas animals use type 2 opsins. Type 2 opsins belong to Class A family of G-protein coupled receptors. Both types are seven-transmembrane receptors and bind covalently retinal as chromophore, which turns them into photoreceptors sensing light. However, both types are not related on the sequence level.
In other fungi such as Blastocladiella emersonii, a flagellated early-diverging fungus, type 1 opsins are used for phototaxis. However, in S. punctatus type 1 opsins do not exist, but a putative type 2 opsin. It shares with other G-protein-coupled receptors a number of conserved motifs and amino acids including the lysine corresponding to residue 296 in cattle rhodopsin, which is important for retinal binding and light sensing. It is as suggested by template-based structure modelling also structurally similar to animal type 2 opsins. At least computationally, it can bind retinal as chromophore. However, it prefers binding 9-cis-retinal, unlike most classical animal type 2 opsins, such as cattle rhodopsin, which binds 11-cis-retinal in the dark state. However, the biological function of the S. punctatus opsin is unknown. Whether it is indeed a type 2 opsin is also unclear, since it is absent from a comprehensive opsin pyhlogeny that covers as many opsins as possible. In principle, if it is a photoreceptor, it could have evolved light sensitivity, independently.
Fanzor endonuclease
Fanzor is a protein encoded by eukaryotic transposons and is thought to have originated from TnpB, an effector of the prokaryotic RNA-guided system known as OMEGA. TnpB is also considered the putative ancestor of Cas12, an RNA-guided endonuclease utilized in the CRISPR-Cas system. This suggests a connection between Fz, TnpB, and Cas12, despite their different roles and context in prokaryotic and eukaryotic cells. Spizellomyces punctatus was used extensively to study the structure of Fanzor.
References
Chytridiomycota
Fungus species | Spizellomyces punctatus | [
"Biology"
] | 2,127 | [
"Fungi",
"Fungus species"
] |
66,251,281 | https://en.wikipedia.org/wiki/Gem%C3%BCtlose%20psychopathy | Gemütlose psychopathy was one of the initial seven forms of psychopathy identified by Emil Kraepelin and later psychiatrists. It was of particular interest to forensic psychiatrists and criminologists as it and haltlose personality disorder were considered the only two psychopathies that "had high levels of criminal behavior" without external influence, and thus made up the minority of psychopaths who are "virtually doomed to commit crimes" by virtue only of their own constitution.
They were described by Kurt Schneider as essentially lacking honor, pity, shame, remorse or conscience.
It is not a term in regular use today, but was used to describe what is today known as antisocial personality disorder.
Characteristics
Homburger opined that there was no means of rehabilitating youth, as they were disrespectful and devoid of any moral sense – taking pleasure in images of vengeance and screaming madly.
Dr. E.H. Hughes noted that two-thirds of Huntington's disease patients had previously been diagnosed as Haltlose or Gemütlose psychopaths.
Masturbation is more prevalent in Haltlose and Gemütlose psychopaths than in other disorders. In adolescence they struggle with an overactive sex drive.
Notable cases
Wolfgang Scheler, the son of philosopher Max Scheler, was sent to Schneider at his father's request in 1923 and diagnosed as both a haltlose and Gemütlose psychopath. After two decades of an unstable life that involved pimping among other crimes, he was sent to Sachsenhausen concentration camp in 1939; there are no further records of him.
In 1969, it was suggested that maternal deprivation experiments on monkeys could induce a primate form of Gemütlose psychopathy.
References
Anti-social behaviour
Forensic psychiatry
Mental health in Germany
Criminology | Gemütlose psychopathy | [
"Biology"
] | 377 | [
"Anti-social behaviour",
"Behavior",
"Human behavior"
] |
66,253,186 | https://en.wikipedia.org/wiki/John%20Haddon | John Haddon (1845–1924) was a Scottish physician, dietitian and vegetarianism activist.
Biography
Haddon's father was Andrew Haddon (1818–1894), his mother was Anne White (1821–1878) and he had ten siblings. He was educated at the University of Edinburgh where he obtained his M.D. degree. He was awarded the Thesis Gold Medal in 1869. He set up his medical practice in Manchester and later Hawick. Around 1880 he published a paper on Public Health for the Manchester and Salford Sanitary Association. In 1882 at the age of 37, Haddon went on a world trip across the Atlantic through America and Canada and through the Pacific. He contributed to the Hawick Archaeological Society in 1897.
Haddon resided in Denholm and authored papers on dietetics. He designed and commissioned "The Text House" in Denholm, a category B listed building. He held a number of unorthodox views. Haddon opposed marriage and described it as an "unnatural and immoral institution". Instead, he promoted individualism. He identified as a materialist but also expressed a belief in God which confused Rev David Cathels.
Haddon never married and had no children. He died age 80 at his residence in Denholm. His remains were cremated at Glasgow and the ashes were deposited at the crematorium.
Vegetarianism
Haddon became a vegetarian in 1896 and practiced fasting which he claimed improved his health. He opposed drug therapy and attributed health to diet only. He believed that a minimalist diet would cure every disease and prolong life.
Haddon promoted a low-fat vegetarian diet and attributed all disease to unhealthy foods. He opposed the drinking of water and became known as an "anti-water medical man". Haddon stated that vegetarianism was a panacea for drinking habits and that he himself drank nothing at all. Haddon stated that one could go without water if a strict vegetarian diet was adhered to as plenty of fluid could be obtained in fruits and other foods. Haddon did not eat eggs or drink milk. He said that milk is only natural to the calf and disappears when it can feed itself and wild eggs only lay eggs that hatch. He ate only one meal a day and his diet was almost vegan. The only animal product that he would eat was butter.
Haddon was associated with the Vegetarian Society. In 1899, he attended the 52nd anniversary of the Vegetarian Society in Manchester. Haddon read a paper, "Experiments in dietetics" which argued that vegetarianism could cure alcoholism. In 1900, Haddon attended a branch meeting for The British Medical Journal at Newtown St Boswells. He read a paper "Elimination of Animal Products From Diet". Haddon argued from personal experience that a vegetarian diet improved digestion, ability to sleep, increased vigour, increased bodily temperature, improved the nervous system and gave a higher moral tone by giving up animal foods. The paper caused considerable discussion but few of the members present agreed with Haddon's views.
Haddon criticized overeating. In 1905, Haddon debated Dr. Litton Forbes on the subject "Do We Eat Too Much?". Their answers were published in The Grand Magazine. Haddon argued that the practice of medicine was not reaching its full potential because it was not giving dietetics a key priority. In 1919, he commented that "when we have a true science of dietetics we will be able to prescribe a diet as easily as we can now prescribe drugs, and with more beneficial and lasting results."
In 1911, Haddon authored a book entitled A Doctor's Discovery, which recommended fasting and a vegetarian diet. The book argued that food is the chief cause of disease but despite this doctors continue to cram foods into their patients to 'keep up their strength' which in many cases deprives them of recovery.
Alexander Haig who was a friend of Haddon disputed his "one meal a day" treatment for neurasthenia and other disorders. Haig commented that "this treatment entails underfeeding and leads eventually to defective nutrition of all the muscles, including that of the heart". Haddon advocated a vegetarian diet to treat gout and many other diseases. The subject of gout was debated in the British Medical Journal and Arthur P. Luff disagreed with Haddon's suggestion that a vegetarian diet was necessary to treat gout.
At age 73, Haddon commented in the British Medical Journal, "I am going to try to be a fruitarian, for I believe that man is a frugivorous animal, as our comparative anatomists have all along taught."
Haddon supported the Vegetarian Federal Union.
Selected publications
Acute Rheumatism in Private Practice (The Edinburgh Medical Journal, 1873)
A Report on Infection (British Medical Journal, 1875)
On Tetany (British Medical Journal, 1875)
On Intemperance in Women (British Medical Journal, 1876)
Clothing, and Its Relation to Health and Disease (1878)
Health and How to Preserve It (1878)
Note on the Excretion of Urea (The Edinburgh Medical Journal, 1879)
Vegetarianism And Gout (British Medical Journal, 1898)
Food versus Physic (The Edinburgh Medical Journal, 1900)
Influenza and Pneumonia (British Medical Journal, 1900)
Sir William Banks on Cancer (British Medical Journal, 1900)
Therapeutic Value Of Vegetable Diet (British Medical Journal, 1902)
Fasting in Therapeutics (The Lancet, 1904)
Diet in Chronic Diseases (The Lancet, 1905)
Physician, Heal Thyself (The Westminster Review, 1909)
The Treatment Of Neurasthenia (1913)
A Doctor's Discovery: Or the Elixir of Life. With Appendices on Fasting and Cooking (1911, 1918)
Quotes
References
1845 births
1924 deaths
19th-century Scottish medical doctors
20th-century Scottish medical doctors
Alumni of the University of Edinburgh Medical School
Anti-obesity activists
Dietitians
Fasting advocates
Gout researchers
Materialists
People associated with the Vegetarian Society
Scottish medical researchers
Scottish medical writers
Scottish temperance activists
Scottish vegetarianism activists
Opponents of tea drinking | John Haddon | [
"Physics"
] | 1,254 | [
"Materialism",
"Matter",
"Materialists"
] |
66,254,033 | https://en.wikipedia.org/wiki/Methylol%20urea | Methylol urea is the organic compound with the formula H2NC(O)NHCH2OH. It is a white, water-soluble solid that decomposes near 110 °C.
Methylolurea is the product of the condensation reaction of formaldehyde and urea. As such it is an intermediate in the formation of urea-formaldehyde resins as well as fertilizer compositions such as methylene diurea. It has also been investigated as a corrosion inhibitor.
References
Ureas | Methylol urea | [
"Chemistry"
] | 109 | [
"Organic compounds",
"Ureas"
] |
66,254,045 | https://en.wikipedia.org/wiki/Clinical%20collaboration | Clinical collaboration is the collaboration of organizations, teams of professionals, or small groups of individual professionals, each having skills, equipment or information that will complement what their partner has, all seeking to be more effective. Choosing one's partner is important, and has been described as "similar to the accreditation process of Joint Commission on the Accreditation of Healthcare Organizations." "CHOP Hub For Clinical Collaboration Arrives on the Skyline in University City, West Philadelphia" was a 2020 headline describing a coming 19-story medical building.
While clinical collaboration, which has been described as a "culture" rather than as something to be purchased, is not a "full-asset merger," a clinical collaboration does aid the financial goal of
"to maximize the value of" a franchise. It also gives more eyes to aid in reducing risk.
Overview
Clinical collaboration is not "one size fits all", and its areas of potential effectiveness include medical/pharmaceutical research, healthcare/doctors and nurses, emergency room care, and ambulatory and ambulance services. One potential obstacle they all face is anti-trust law, but proof of concept exists: partnership contract renewals.
Other concepts affecting healthcare delivery are "clinical affiliation" and "non-clinical collaboration."
Medical research
Cancer research is an example where clinical collaboration can advance state of the art.
Pharmaceutical research
Major pharmaceutical companies such as Pfizer and Bristol-Myers Squibb have arranged clinical collaborations with companies such as NeoImmuneTech, Checkmate Pharmaceuticals and Kitov for testing and evaluating the effectiveness of combinations of existing medicines. If the tested combination attains regulatory approval, "it opens up new patient populations for each company’s drug."
Healthcare
Clinical collaboration between facilities permits sharing the availability of specialists and high tech equipment, often involving specialized communication links to facilitate data sharing.
Issues that must be prearranged include patient data privacy and security, including HIPAA compliance. Some of this is software apps that go beyond standard data sharing using more "aware" software.
Rural areas need it to provide service, and small healthcare providers in large areas need it to survive. In these seemingly asymmetrical arrangements, there is an avoidable potential for domination for which due diligence and preplanning and proper preparation is needed.
Doctors and nurses
Clinical collaboration, properly implemented, must be seamless to be most effective. This includes overlapping staffing and concurrent shifts of doctors with varying specialties and focus, along with nurses and paramedics. The goal is not new, and the situation has improved with use of technology
that enables going beyond paper-based records.
Contrast to affiliation
Even though there may be financial benefits to the arrangement, it contrasts with financial affiliation, where profit is the driving motive. An example is where a research project is incurring major expenditures with cost writeoffs: "cost-sharing clinical collaboration" enables "building value" that goes beyond making money to "encouraging activity" that is high risk but, if successful in the long run, will save lives. The medical director of the Mayo Clinic Care Network referred to "due diligence" in an article about Clinical Collaboration as an alternative to health care mergers and acquisitions.
A well implemented medical facility agreement "maintains each hospital’s independence in governance, budgeting, labor agreements and will not move or remove any local services."
References
Health care
Collaboration
Organizational behavior | Clinical collaboration | [
"Biology"
] | 677 | [
"Behavior",
"Organizational behavior",
"Human behavior"
] |
66,256,557 | https://en.wikipedia.org/wiki/Nitrogen%20solubility%20index | The nitrogen solubility index (NSI) is a measure of the solubility of the protein in a substance. It is typically used as a quick measure of the functionality of a protein, for example to predict the ability of the protein to stabilise foams, emulsions or gels. To determine the NSI, the sample is dried, dispersed in a 0.1 M salt solution, centrifuged and filtered. The NSI is the amount of Nitrogen in this filtered solution divided by the nitrogen in the initial sample, as measured by the Kjeldahl method.
The relevance of the NSI is based on the fact that proteins are the major biological source of Nitrogen: for various types of protein, there are empirical formulas which correlate the nitrogen content to the protein content. Other related measures of protein solubility are the Protein Solubility Index (PSI), the Protein Dispersibility index (PDI). These are based on a specific protein assay, rather than a nitrogen assay, and the dispersibility index differs from the solubility index, in that the sample is dispersed with a high-shear mixer and then strained through a screen instead of being centrifuged and filtered.
References
Protein methods
Food analysis | Nitrogen solubility index | [
"Chemistry",
"Biology"
] | 261 | [
"Biochemistry methods",
"Protein methods",
"Protein biochemistry",
"Food analysis",
"Food chemistry"
] |
66,257,955 | https://en.wikipedia.org/wiki/Cortinarius%20heatherae | Cortinarius heatherae is a species of webcap. It was described in 2020 by Andy Overall from a specimen found at Heathrow Airport. He named the species in honour of his wife, Heather Overall. Along with five other British webcaps, C. heatherae was selected by Kew Gardens as a highlight of taxa described by the organisation's staff and affiliates in 2020.
Taxonomy
Cortinarius heatherae was described in a 2020 research note in the journal Fungal Diversity by Andy Overall. The description was based on a collection made by Overall in 2018 at Heathrow Airport, England. The specific name honours Heather Overall, Andy Overall's wife. Phylogenetic analysis placed the species in Cortinarius sect. Bovini. It is closely related to C. subbrunneus, and is a sister species to both C. subbrunneus and C. subbrunneoideus.
C. britannicus was one of over 150 botanical and mycological taxa described by staff or affiliates of Kew Gardens in 2020. In a year-end round-up, Kew scientists selected ten highlights, one of which was six newly described British Cortinarius species: C. heatherae described from Heathrow Airport; C. ainsworthii from Brighton; C. britannicus from Caithness; C. scoticus and C. aurae from the Black Wood of Rannoch; and C. subsaniosus from Cumbria. In a press release, Kew identified Cortinarius species as "ecologically important in supporting the growth of plants, particularly trees such as oak, beech, birch and pine" and playing "a key role in the carbon cycling of woodlands and providing nitrogen to trees".
Description
Cortinarius heatherae mushrooms have a cap measuring wide, at first convex, later plano-convex with a broad umbo. The surface is covered in silky whitish fibrils when the mushroom is young, though these are later more apparent only in the margin. It is reddish brown, later darkening or blackening in large spots, and hygrophanous. The gills are adnate (attached to the stem on their whole length), medium spaced, and fairly broad. At first, they are light brown with a paler edge, becoming rusty brown to dark brown at maturity. The stem measures long, and is thick. It is more or less club-shaped. At first, it is covered with greyish white silky fibrils, though it is later a pale greyish brown. The flesh is greyish brown and marbled hygrophanous. The universal veil is cream-coloured, forming scattered patterns on the surface of the stem. No record was made of odour.
Microscopic characteristics
Cortinarius heatherae has basidiospores that measure 9 to 11 by 5.5 to 7 micrometres (μm), averaging 10.0 by 6.2 μm. They mostly almond-shaped, strongly warty, and strongly dextrinoid, meaning they stain a deep reddish to reddish-brown when Melzer's reagent or Lugol's solution is applied. The basidia measure 33 to 46 by 7 to 11 μm and are somewhat club-shaped, with four sterigmata. The flesh in the gills is made up of smooth hyphae. The surface of the pileipellis is pale, consisting of parallel hyphae. They are 6 to 8 μm wide, smooth to encrusted with spot-like encrustations. Lower, the cells are colourless, measuring 17 to 50 by 11 to 19, and smooth.
Similar species
Cortinarius heatherae is typical of species in Cortinarius sect. Bovini, featuring medium-sized, brown mushrooms; caps that become dark spotted with age; the stem is club-shaped; and the spores are almond-shaped. The sister species C. subbrunneus and C. subbrunneoideus grow in coniferous forests, and also differ in microscopic features: the spores of C. subbrunneus are narrower and slightly larger, whereas the spores of C. subbrunneoideus are smaller and only somewhat to moderately dextrinoid.
Ecology
Cortinarius heatherae is known from temperate mixed forests containing English oak, evergreen oak, and willows on calcareous soil. It is known only from Britain.
References
heatherae
Fungi described in 2020
Fungi of Europe
Fungus species | Cortinarius heatherae | [
"Biology"
] | 928 | [
"Fungi",
"Fungus species"
] |
66,258,404 | https://en.wikipedia.org/wiki/List%20of%20plant%20genera%20named%20for%20people%20%28A%E2%80%93C%29 | Since the first printing of Carl Linnaeus's Species Plantarum in 1753, plants have been assigned one epithet or name for their species and one name for their genus, a grouping of related species. Thousands of plants have been named for people, including botanists and their colleagues, plant collectors, horticulturists, explorers, rulers, politicians, clerics, doctors, philosophers and scientists. Even before Linnaeus, botanists such as Joseph Pitton de Tournefort, Charles Plumier and Pier Antonio Micheli were naming plants for people, sometimes in gratitude for the financial support of their patrons.
Early works researching the naming of plant genera include an 1810 glossary by and an etymological dictionary in two editions (1853 and 1856) by Georg Christian Wittstein. Modern works include The Gardener's Botanical by Ross Bayton, Index of Eponymic Plant Names and Encyclopedia of Eponymic Plant Names by Lotte Burkhardt, Plants of the World by Maarten J. M. Christenhusz (lead author), Michael F. Fay and Mark W. Chase, The A to Z of Plant Names by Allan J. Coombes, the four-volume CRC World Dictionary of Plant Names by Umberto Quattrocchi, and Stearn's Dictionary of Plant Names for Gardeners by William T. Stearn; these supply the seed-bearing genera listed in the first column below. Excluded from this list are genus names not accepted (as of January 2021) at Plants of the World Online, which includes updates to Plants of the World (2017).
Key
Ba = listed in Bayton's The Gardener's Botanical
Bt = listed in Burkhardt's Encyclopedia of Eponymic Plant Names
Bu = listed in Burkhardt's Index of Eponymic Plant Names
Ch = listed in Christenhusz's Plants of the World
Co = listed in Coombes's The A to Z of Plant Names
Qu = listed in Quattrocchi's CRC World Dictionary of Plant Names
St = listed in Stearn's Dictionary of Plant Names for Gardeners
In addition, Burkhardt's Index is used as a reference for every row in the table not cited to Stearn.
Genera
See also
List of plant genus names with etymologies: A–C, D–K, L–P, Q–Z
List of plant family names with etymologies
Notes
Citations
References
See http://creativecommons.org/licenses/by/4.0/ for license.
See http://creativecommons.org/licenses/by/4.0/ for license.
See terms of use.
Further reading
Systematic
Systematic
Taxonomy (biology)
Glossaries of biology
Gardening lists
Genera named for people (A-C)
Named for people (A-C)
Wikipedia glossaries using tables
Lists of eponyms | List of plant genera named for people (A–C) | [
"Biology"
] | 594 | [
"Lists of plants",
"Plants",
"Lists of biota",
"Taxonomy (biology)",
"Taxonomic lists",
"Glossaries of biology"
] |
66,258,503 | https://en.wikipedia.org/wiki/Audrey%20Cameron | Audrey Cameron is a Chancellor's Fellow working at the University of Edinburgh. She is Deaf and uses British Sign Language.
Biography
Cameron gained her degree in chemistry from the University of West of Scotland before achieving a PhD in Chemistry from the University of Strathclyde with a thesis on hydrogel polymer membranes. She then carried out her postdoctoral research at both Strathclyde and Durham Universities, before completing a PGCE course in Secondary Education (Chemistry with Science) at the Moray House School of Education and Sport in 2004, after which she spent some time teaching Chemistry and Science in mainstream schools.
Currently, she is a Chancellor's Fellow in Science Education and BSL. She teaches on the PGDE Secondary Education (Chemistry/ General Science) course and she delivers science workshops for the PGDE Primary Education course. She also delivers the Deaf Studies module as part of the MSc Inclusive Education team. In 2020 she was awarded a five-year Chancellor’s Fellowship, focusing on research on science education and BSL.
Cameron also manages the Scottish Sensory Centre's STEM in BSL Glossary project. This project, which has been active since 2007, aims at developing a glossary of British signs and definitions to cover STEM disciplines and support teaching of such subjects to Deaf pupils. The glossary has nearly 4,500 signs with BSL definitions and examples. Each sign and definition is developed by a team of Deaf scientists, mathematicians, teachers working with deaf children, and BSL sign linguists, in order to be correct both linguistically and scientifically, and to be effective in conveying a concept.
In 2016, Cameron was selected to be part of the exhibition "175 Faces of Chemistry", which showcased the diversity of the chemistry profession through 175 stories of individuals working in chemistry and organised by the Royal Society of Chemistry (RSC) in the lead up of the 175th anniversary of its foundation.
In 2022, Cameron was admitted as an Honorary Fellow of the RSC, which is its most senior category of membership reserved for those who are distinguished in the science or profession of chemistry.
Cameron was appointed Officer of the Order of the British Empire (OBE) in the 2023 Birthday Honours for services to chemical sciences and inclusion in science communications.
In 2024, Cameron was awarded an Honorary Doctorate from the University of the West of Scotland.
References
External links
Living people
Year of birth missing (living people)
Scottish deaf people
BSL users
Alumni of the University of the West of Scotland
Alumni of the University of Strathclyde
Academics of the University of Edinburgh
Polymer scientists and engineers
Officers of the Order of the British Empire
Scottish women chemists
21st-century Scottish chemists
21st-century Scottish women scientists
Deaf scholars and academics
Deaf educators
21st-century Scottish educators
21st-century Scottish women educators | Audrey Cameron | [
"Chemistry",
"Materials_science"
] | 559 | [
"Polymer scientists and engineers",
"Physical chemists",
"Polymer chemistry"
] |
66,259,312 | https://en.wikipedia.org/wiki/SDSS%20J1228%2B1040%20b | SDSS J1228+1040 b is a disputed extrasolar planetesimal orbiting the white dwarf SDSS J1228+1040. It was discovered in 2019 using the variable calcium Ca II emission line.
Unlike other planetesimals around white dwarfs, the planetesimal SDSS J1228+1040 b needs high internal strength and a high density to not be tidally disrupted. The researchers calculate a density of 7.7 g/cm3 or less. This density is close to the density of iron and it is speculated that this planetesimal is the core of a larger body. This larger parent body possibly got its crust and mantle stripped by the white dwarf, leaving the core behind. This crust and mantle material would then form the debris disk, which is now detected around the white dwarf.
At first the size of the planetesimal was estimated to be between 4 and 600 km or between 2 and 200 km for an eccentric orbit, but newer accretion models suggest a minimal radius of 72 km and a lifetime of 1500 years before it is completely sublimated.
The white dwarf SDSS J1228+1040 is surrounded by a debris disk, detected as both spectroscopic metal lines and infrared excess. The white dwarf also shows emission lines. While absorption lines represent metals that are already pollute the atmosphere of the white dwarf, the emission lines are interpreted as sublimated metal gas inside the disk. In the case of SDSS J1228+1040 it is suggested that the gas is sublimated on the surface of the planetesimal. The gas component also shows long-term variability over the 15 years observations. This is interpreted as precession of an assumed to be eccentric orbit of the planetesimal. Other gaseous disks around white dwarfs show similar long-term variability.
A study questions the existence of the planetesimal and instead suggests that the disk is precessing under the forces of general relativity and gas pressure. This eccentricity of the disk should dissipate within 200 years, meaning that the disk must have formed recently.
See also
WD 1145+017 – first planetesimal around a white dwarf
WD 0145+234 – white dwarf with planetesimals being tidally disrupted
ZTF J0139+5245 – white dwarf with a highly eccentric planetesimal
List of smallest exoplanets
List of exoplanets and planetary debris around white dwarfs
References
External links
SIMBAD entry for SDSS J1228+1040
Exoplanets detected by timing
Virgo (constellation)
Sub-Earth exoplanets | SDSS J1228+1040 b | [
"Astronomy"
] | 543 | [
"Virgo (constellation)",
"Constellations"
] |
63,437,511 | https://en.wikipedia.org/wiki/Barnard%20203 | The dark nebula Barnard 203 or Lynds 1448 is located about one degree southwest of NGC 1333 in the Perseus molecular cloud, at a distance of about 800 light-years. Three infrared sources were observed in this region by IRAS, called IRS 1, IRS 2 and IRS 3.
The region also contains multiple Herbig-Haro objects, including HH 193–197, which are driven by the protostars in this region.
The young stellar object population
The source IRS 1 is a class I young stellar object and a binary. IRS 1 is more evolved than most of the protostars in this region and less well-studied.
The source IRS 2 is a binary that is very young (class 0 young stellar object), surrounded by a rotating disk and the system shows a bipolar outflow signature. The system has an hourglass shaped magnetic field that is aligned with the bipolar outflow. Towards the east is the source IRS 2E, a source between a pre-stellar core and a protostar.
The source IRS 3B was studied the most and ALMA showed that it is a triple protostar system with one star forming via disk fragmentation. The two outer stars are separated by 61 and 183 astronomical units from the central star and all three stars are surrounded by a circumstellar disk that shows spiral arms. IRS 3B is a class 0 young stellar object and might be younger than 150,000 years. The two protostellar objects in the center have a mass of about 1 and the protostar further from the center has a mass of about 0.085 . The disk that surrounds the three protostars has an estimated mass of about 0.30 . The sources IRS 3A, B and C show molecular outflows. IRS 3 is also called L1448N.
Another well-studied source in this region is called L1448-mm or L1448C. It is a class 0 young stellar object that drives a highly collimated flow, detected in carbon monoxide, Silicon monoxide and water.
References
Dark nebulae
Barnard objects
Star-forming regions
Perseus (constellation) | Barnard 203 | [
"Astronomy"
] | 434 | [
"Perseus (constellation)",
"Constellations"
] |
63,438,182 | https://en.wikipedia.org/wiki/3CLpro-1 | 3CLpro-1 is an antiviral drug related to rupintrivir which acts as a 3CL protease inhibitor and was originally developed for the treatment of human enterovirus 71. It is one of the most potent of a large series of compounds developed as inhibitors of the viral enzyme 3CL protease, with an in vitro IC50 of 200 nM. It also shows activity against coronavirus diseases such as SARS and MERS, and is under investigation as a potential treatment agent for the viral disease COVID-19.
See also
Carmofur
Ebselen
GC376
GRL-0617
Iscartrelvir
Rupintrivir
Theaflavin digallate
References
Antiviral drugs
SARS-CoV-2 main protease inhibitors | 3CLpro-1 | [
"Biology"
] | 164 | [
"Antiviral drugs",
"Biocides"
] |
63,438,861 | https://en.wikipedia.org/wiki/Pl%40ntNet | Pl@ntNet is a citizen science project for automatic plant identification through photographs and based on machine learning.
History
This project launched in 2009 has been developed by scientists (computer engineers and botanists) from a consortium gathering French research institutes (Institut de recherche pour le développement (IRD), Centre de coopération internationale en recherche agronomique pour le développement (CIRAD), Institut national de la recherche agronomique (INRA), Institut national de recherche en informatique et en automatique (INRIA) and the network Tela Botanica, with the support of Agropolis Fondation
).
Platforms
An app for smartphones (and a web version) was launched in 2013, which allows to identify thousands of plant species from photographs taken by the user. It is available in several languages.
As of 2019 it had been downloaded over 10 million times, in more than 180 countries worldwide.
Projects
In 2019, Pl@ntNet has 22 projects:
References
Botany
Citizen science
Biology websites
Internet properties established in 2009 | Pl@ntNet | [
"Biology"
] | 220 | [
"Plants",
"Botany"
] |
63,438,996 | https://en.wikipedia.org/wiki/Cruentomycena%20viscidocruenta | Cruentomycena viscidocruenta, commonly known as the ruby bonnet, is a species of agaric fungus in the family Mycenaceae. It is found in moist forested areas of Australia and New Zealand, often in small groups on rotting wood. Care in identification needs to be made to distinguish the ruby bonnet from red forms of Hygrocybe mushrooms.
References
External links
Mycenaceae
Fungi described in 1924
Fungi of Australia
Fungi of New Zealand
Fungus species | Cruentomycena viscidocruenta | [
"Biology"
] | 100 | [
"Fungi",
"Fungus species"
] |
63,439,408 | https://en.wikipedia.org/wiki/Amanita%20pyramidifera | Amanita pyramidifera is a basidiomycete mushroom of the genus Amanita. The cap is in diameter, covered in pyramid type scales which may be white or greyish brown. The stem is long, white with pyramidal scales.
Found in eastern Australia, the species grows in moist sites associated with eucalyptus forest or rainforest.
References
Pyramidifera
Fungi described in 1980
Fungi of Australia
Fungus species | Amanita pyramidifera | [
"Biology"
] | 84 | [
"Fungi",
"Fungus species"
] |
63,439,560 | https://en.wikipedia.org/wiki/GC376 | GC376 is a broad-spectrum antiviral medication under development by the biopharmaceutical company Anivive Lifesciences for therapeutic uses in humans and animals. Anivive licensed the exclusive worldwide patent rights to GC376 from Kansas State University. As of 2020, GC376 is being investigated as a treatment for COVID-19. GC376 shows activity against many human and animal viruses, including coronavirus and norovirus; the most extensive research has been multiple in vivo studies in cats treating a coronavirus, which causes deadly feline infectious peritonitis. Other research supports use in porcine epidemic diarrhea virus.
COVID-19
Since GC376 shows broad-spectrum activity against coronavirus, early on during the pandemic of 2020, it was suggested as a potential treatment for COVID-19. In response to the crisis, researchers at the University of Arizona published in vitro research indicating GC376 is highly active against 3CLpro in SARS-CoV-2 (the coronavirus which causes COVID-19). Another group of virologists at the University of Alberta led by D. Lorne Tyrrell then released a separate publication confirming GC376's activity against 3CLpro in SARS-CoV-2 and also indicating GC376 had a potent antiviral effect.
Pharmacology
Pharmacodynamics
GC376 is a protease inhibitor. It blocks 3CLpro, a protease common to many (+)ssRNA viruses, thereby preventing the viral polyprotein from maturing into its functional parts. Chemically, GC376 is the bisulfite adduct of the aldehyde GC373, and it behaves as a prodrug for that compound. This aldehyde forms a covalent bond with the cysteine-144 residue at the protease's active site, giving a monothioacetal and blocking the enzyme's normal function.
See also
3CLpro-1
Carmofur
Ebselen
GRL-0617
Rupintrivir
Theaflavin digallate
Paxlovid
References
External links
Anivive Pharmaceuticals
Antiviral drugs
SARS-CoV-2 main protease inhibitors | GC376 | [
"Biology"
] | 485 | [
"Antiviral drugs",
"Biocides"
] |
63,439,671 | https://en.wikipedia.org/wiki/Pterotheca%20attenuata | Pterotheca attenuata is a fossil species from the Ordovician upper Midwestern United States. It has been variously classified as a monoplacophoran, bellerophont, or another type of gastropod.
Remains of the animal were found in deposits laid down in shallow marine waters, as the Decorah Shale and Platteville Limestone of the United States Midwest. It is often misclassified in museum collections because of its unusual morphology and therefore documentation of its range and abundance is poor.
Preservation and morphology
The shell is composed of two slightly concave sub-triangular layers that connect along the anterior most side. The dorsal layer has a ridge that extends perpendicularly from the rest of shell along the median plane. The underside of the ventral most layer is effaced and smooth, but the top of the ventral layer and the bottom of the dorsal layer both show a slight medial ridge.
P. attenuata is most often preserved in fine-grained sedimentary rock like shale and limestone, but its range likely extends outside of these facies. The shell is often found broken and the two layers separated. P. attenuata's unusual shape and the fragmentary nature of many of its fossils are both causes of its frequent misclassification as a brachiopod.
References
Bibliography
Paleozoic life of North America
Prehistoric life of North America
Ordovician United States
Paleontology in Minnesota
Fossil taxa described in 1940
Controversial taxa | Pterotheca attenuata | [
"Biology"
] | 296 | [
"Biological hypotheses",
"Controversial taxa"
] |
63,440,197 | https://en.wikipedia.org/wiki/NGC%20790 | NGC 790 is a lenticular galaxy in the constellation Cetus. It is estimated to be 233 million light-years from the Milky Way and has a diameter of approximately 90,000 light years. NGC 790 was discovered on September 10, 1785 by the German-British astronomer William Herschel.
See also
List of NGC objects (1–1000)
References
External links
0790
Lenticular galaxies
Cetus
007677 | NGC 790 | [
"Astronomy"
] | 88 | [
"Cetus",
"Constellations"
] |
63,440,650 | https://en.wikipedia.org/wiki/Equivalents%20of%20the%20Axiom%20of%20Choice | Equivalents of the Axiom of Choice is a book in mathematics, collecting statements in mathematics that are true if and only if the axiom of choice holds. It was written by Herman Rubin and Jean E. Rubin, and published in 1963 by North-Holland as volume 34 of their Studies in Logic and the Foundations of Mathematics series. An updated edition, Equivalents of the Axiom of Choice, II, was published as volume 116 of the same series in 1985.
Topics
At the time of the book's original publication, it was unknown whether the axiom of choice followed from the other axioms of Zermelo–Fraenkel set theory (ZF), or was independent of them, although it was known to be consistent with them from the work of Kurt Gödel. This book codified the project of classifying theorems of mathematics according to whether the axiom of choice was necessary in their proofs, or whether they could be proven without it. At approximately the same time as the book's publication, Paul Cohen proved that the negation of the axiom of choice is also consistent, implying that the axiom of choice, and all of its equivalent statements in this book, are indeed independent of ZF.
The first edition of the book includes over 150 statements in mathematics that are equivalent to the axiom of choice, including some that are novel to the book. This edition is divided into two parts, the first involving notions expressed using sets and the second involving classes instead of sets. Within the first part, the topics are grouped into statements related to the well-ordering principle, the axiom of choice itself, trichotomy (the ability to compare cardinal numbers), and Zorn's lemma and related maximality principles. This section also includes three more chapters, on statements in abstract algebra, statements for cardinal numbers, and a final collection of miscellaneous statements. The second section has four chapters, on topics parallel to four of the first section's chapters.
The book includes the history of each statement, and many proofs of their equivalence. Rather than ZF, it uses Von Neumann–Bernays–Gödel set theory for its proofs, mainly in a form called NBG0 that allows urelements (contrary to the axiom of extensionality) and also does not include the axiom of regularity.
The second edition adds many additional equivalent statements, more than twice as many as the first edition, with an additional list of over 80 statements that are related to the axiom of choice but not known to be equivalent to it. It includes two added sections, one on equivalent statements that need the axioms of extensionality and regularity in their proofs of equivalence, and another on statements in topology, mathematical analysis, and mathematical logic. It also includes more recent developments on the independence of the axiom of choice, and an improved account of the history of Zorn's lemma.
Audience and reception
This book is written as a reference for professional mathematicians, especially those working in set theory. Reviewer Chen Chung Chang writes that it "will be useful both to the specialist in the field and to the general working mathematician", and that its presentation of results is "clear and lucid". By the time of the second edition, reviewers J. M. Plotkin and David Pincus both called this "the standard reference" in this area.
References
External links
Equivalents of the Axiom of Choice, II at the Internet Archive
Axiom of choice
Mathematics books
1963 non-fiction books
1985 non-fiction books | Equivalents of the Axiom of Choice | [
"Mathematics"
] | 724 | [
"Axiom of choice",
"Axioms of set theory",
"Mathematical axioms"
] |
63,440,841 | https://en.wikipedia.org/wiki/NGC%20530 | NGC 530, also known as IC 106, is a lenticular galaxy in the constellation Cetus. It is approximately 226 million light years from the Milky Way and has a diameter of around 100,000 light years. The object was discovered on November 20, 1886, by the American astronomer Lewis A. Swift, who listed it as NGC 530, and rediscovered on November 16, 1887, by Guillaume Bigourdan, who listed it as IC 106.
See also
List of NGC objects (1–1000)
References
External links
0530
IC objects
Cetus
Barred lenticular galaxies
005210 | NGC 530 | [
"Astronomy"
] | 119 | [
"Cetus",
"Constellations"
] |
63,440,881 | https://en.wikipedia.org/wiki/NGC%20550 | NGC 550 is a spiral galaxy in the constellation Cetus. It is estimated to be about 300 million light-years from the Milky Way and has a diameter of approximately 110,000 light years. The German-British astronomer William Herschel discovered it on 8 October 1785.
One supernova has been observed in NGC 550: SN 1961Q (type unknown, mag. 17.2) was discovered by Milton Humason on 30 November 1961.
See also
List of NGC objects (1–1000)
References
External links
Spiral galaxies
550
Cetus
005374 | NGC 550 | [
"Astronomy"
] | 115 | [
"Cetus",
"Constellations"
] |
63,441,131 | https://en.wikipedia.org/wiki/Radium%20fluoride | Radium fluoride is an inorganic compound with a chemical formula of . This salt, like all radium compounds, is highly radioactive. It can be coprecipitated with lanthanide fluorides. Radium fluoride has the same crystal form as calcium fluoride (fluorite). However, calculations suggest that radium fluoride vapor consists of RaF2 molecules, with a bond angle of 118°, due to substantial covalent interaction within the molecule.
Production
Radium fluoride can be produced by the reaction of radium metal and hydrogen fluoride gas:
References
See also
Radium compounds
Fluorides
Alkaline earth metal halides | Radium fluoride | [
"Chemistry"
] | 141 | [
"Fluorides",
"Salts"
] |
63,441,722 | https://en.wikipedia.org/wiki/Microsoft%20MACRO-80 | Microsoft MACRO-80 (often shortened to M80) is a relocatable macro assembler for Intel 8080 and Zilog Z80 microcomputer systems.
The complete MACRO-80 package includes the MACRO-80 Assembler, the LINK-80 Linking Loader, and the CREF-80 Cross Reference Facility. The LIB-80 Library Manager is included in CP/M versions only.
The list price at the time was $200.
Overview
A MACRO-80 source program consists of a series of statements. Each statement must follow a predefined format. Source lines up to 132 characters in length are supported. M80 accepts source files almost identical to files for Intel-compatible assemblers. It also supports several switches in the command string. Some can be used to control the format of the source file. A switch can be set to allow support for Z80 mnemonics.
MACRO-80 runs on Digital Research CP/M, Intel ISIS-II, Tandy TRSDOS, Tektronix TEKDOS, and Microsoft MSX-DOS.
See also
Microsoft Macro Assembler
Assembly language
High-level assembler
Comparison of assemblers
References
External links
CP/M-80 Information and Download Page
Assemblers
MACRO-80
MSX-DOS | Microsoft MACRO-80 | [
"Technology"
] | 261 | [
"Computing platforms",
"MSX-DOS"
] |
63,442,098 | https://en.wikipedia.org/wiki/Hyperbolastic%20functions | The hyperbolastic functions, also known as hyperbolastic growth models, are mathematical functions that are used in medical statistical modeling. These models were originally developed to capture the growth dynamics of multicellular tumor spheres, and were introduced in 2005 by Mohammad Tabatabai, David Williams, and Zoran Bursac. The precision of hyperbolastic functions in modeling real world problems is somewhat due to their flexibility in their point of inflection. These functions can be used in a wide variety of modeling problems such as tumor growth, stem cell proliferation, pharma kinetics, cancer growth, sigmoid activation function in neural networks, and epidemiological disease progression or regression.
The hyperbolastic functions can model both growth and decay curves until it reaches carrying capacity. Due to their flexibility, these models have diverse applications in the medical field, with the ability to capture disease progression with an intervening treatment. As the figures indicate, hyperbolastic functions can fit a sigmoidal curve indicating that the slowest rate occurs at the early and late stages. In addition to the presenting sigmoidal shapes, it can also accommodate biphasic situations where medical interventions slow or reverse disease progression; but, when the effect of the treatment vanishes, the disease will begin the second phase of its progression until it reaches its horizontal asymptote.
One of the main characteristics these functions have is that they cannot only fit sigmoidal shapes, but can also model biphasic growth patterns that other classical sigmoidal curves cannot adequately model. This distinguishing feature has advantageous applications in various fields including medicine, biology, economics, engineering, agronomy, and computer aided system theory.
Function H1
The hyperbolastic rate equation of type I, denoted H1, is given by
where is any real number and
is the population size at . The parameter represents carrying capacity, and parameters and jointly represent growth rate. The parameter gives the distance from a symmetric sigmoidal curve. Solving the hyperbolastic rate equation of type I for gives
where is the inverse hyperbolic sine function. If one desires to use the initial condition , then can be expressed as
.
If , then reduces to
.
In the event that a vertical shift is needed to give a better model fit, one can add the shift parameter , which would result in the following formula
.
The hyperbolastic function of type I generalizes the logistic function. If the parameters , then it would become a logistic function. This function is a hyperbolastic function of type I. The standard hyperbolastic function of type I is
.
Function H2
The hyperbolastic rate equation of type II, denoted by H2, is defined as
where is the hyperbolic tangent function, is the carrying capacity, and both and jointly determine the growth rate. In addition, the parameter represents acceleration in the time course. Solving the hyperbolastic rate function of type II for gives
.
If one desires to use initial condition then can be expressed as
.
If , then reduces to
.
Similarly, in the event that a vertical shift is needed to give a better fit, one can use the following formula
.
The standard hyperbolastic function of type II is defined as
.
Function H3
The hyperbolastic rate equation of type III is denoted by H3 and has the form
,
where > 0. The parameter represents the carrying capacity, and the parameters and jointly determine the growth rate. The parameter represents acceleration of the time scale, while the size of represents distance from a symmetric sigmoidal curve. The solution to the differential equation of type III is
,
with the initial condition we can express as
.
The hyperbolastic distribution of type III is a three-parameter family of continuous probability distributions with scale parameters > 0, and ≥ 0 and parameter as the shape parameter. When the parameter = 0, the hyperbolastic distribution of type III is reduced to the weibull distribution. The hyperbolastic cumulative distribution function of type III is given by
,
and its corresponding probability density function is
.
The hazard function (or failure rate) is given by
The survival function is given by
The standard hyperbolastic cumulative distribution function of type III is defined as
,
and its corresponding probability density function is
.
Properties
If one desires to calculate the point where the population reaches a percentage of its carrying capacity , then
one can solve the equation
for , where . For instance, the half point can be found by setting .
Applications
According to stem cell researchers at McGowan Institute for Regenerative Medicine at the University of Pittsburgh, "a newer model [called the hyperbolastic type III or] H3 is a differential equation that also describes the cell growth. This model allows for much more variation and has been proven to better predict growth."
The hyperbolastic growth models H1, H2, and H3 have been applied to analyze the growth of solid Ehrlich carcinoma using a variety of treatments.
In animal science, the hyperbolastic functions have been used for modeling broiler chicken growth. The hyperbolastic model of type III was used to determine the size of the recovering wound.
In the area of wound healing, the hyperbolastic models accurately representing the time course of healing. Such functions have been used to investigate variations in the healing velocity among different kinds of wounds and at different stages in the healing process taking into consideration the areas of trace elements, growth factors, diabetic wounds, and nutrition.
Another application of hyperbolastic functions is in the area of the stochastic diffusion process, whose mean function is a hyperbolastic curve. The main characteristics of the process are studied and the maximum likelihood estimation for the parameters of the process is considered.
To this end, the firefly metaheuristic optimization algorithm is applied after bounding the parametric space by a stage wise procedure. Some examples based on simulated sample paths and real data illustrate this development. A sample path of a diffusion process models the trajectory of a particle embedded in a flowing fluid and subjected to random displacements due to collisions with other particles, which is called Brownian motion. The hyperbolastic function of type III was used to model the proliferation of both adult mesenchymal and embryonic stem cells; and, the hyperbolastic mixed model of type II has been used in modeling cervical cancer data. Hyperbolastic curves can be an important tool in analyzing cellular growth, the fitting of biological curves, the growth of phytoplankton, and instantaneous maturity rate.
In forest ecology and management, the hyperbolastic models have been applied to model the relationship between DBH and height.
The multivariable hyperbolastic model type III has been used to analyze the growth dynamics of phytoplankton taking into consideration the concentration of nutrients.
Hyperbolastic regressions
Hyperbolastic regressions are statistical models that utilize standard hyperbolastic functions to model a dichotomous or multinomial outcome variable. The purpose of hyperbolastic regression is to predict an outcome using a set of explanatory (independent) variables. These types of regressions are routinely used in many areas including medical, public health, dental, biomedical, as well as social, behavioral, and engineering sciences. For instance, binary regression analysis has been used to predict endoscopic lesions in iron deficiency anemia. In addition, binary regression was applied to differentiate between malignant and benign adnexal mass prior to surgery.
The binary hyperbolastic regression of type I
Let be a binary outcome variable which can assume one of two mutually exclusive values, success or failure. If we code success as and failure as , then for parameter , the hyperbolastic success probability of type I with a sample of size as a function of parameter and parameter vector given a -dimensional vector of explanatory variables is defined as , where , is given by
.
The odds of success is the ratio of the probability of success to the probability of failure. For binary hyperbolastic regression of type I, the odds of success is denoted by and expressed by the equation
.
The logarithm of is called the logit of binary hyperbolastic regression of type I. The logit transformation is denoted by and can be written as
.
Shannon information for binary hyperbolastic of type I (H1)
The Shannon information for the random variable is defined as
where the base of logarithm and . For binary outcome, is equal to .
For the binary hyperbolastic regression of type I, the information is given by
,
where , and is the input data.
For a random sample of binary outcomes of size , the average empirical information for hyperbolastic H1 can be estimated by
,
where , and is the input data for the observation.
Information Entropy for hyperbolastic H1
Information entropy measures the loss of information in a transmitted message or signal. In machine learning applications, it is the number of bits necessary to transmit a randomly selected event from a probability distribution. For a discrete random variable , the information entropy is defined as
where is the probability mass function for the random variable .
The information entropy is the mathematical expectation of with respect to probability mass function . The Information entropy has many applications in machine learning and artificial intelligence such as classification modeling and decision trees. For the hyperbolastic H1, the entropy is equal to
The estimated average entropy for hyperbolastic H1 is denoted by and is given by
Binary Cross-entropy for hyperbolastic H1
The binary cross-entropy compares the observed with the predicted probabilities. The average binary cross-entropy for hyperbolastic H1 is denoted by and is equal to
The binary hyperbolastic regression of type II
The hyperbolastic regression of type II is an alternative method for the analysis of binary data with robust properties. For the binary outcome variable , the hyperbolastic success probability of type II is a function of a -dimensional vector of explanatory variables given by
,
For the binary hyperbolastic regression of type II, the odds of success is denoted by and is defined as
The logit transformation is given by
Shannon information for binary hyperbolastic of type II (H2)
For the binary hyperbolastic regression H2, the Shannon information is given by
where , and is the input data.
For a random sample of binary outcomes of size , the average empirical information for hyperbolastic H2 is estimated by
where , and is the input data for the observation.
Information Entropy for hyperbolastic H2
For the hyperbolastic H2, the information entropy is equal to
and the estimated average entropy for hyperbolastic H2 is
Binary Cross-entropy for hyperbolastic H2
The average binary cross-entropy for hyperbolastic H2 is
Parameter estimation for the binary hyperbolastic regression of type I and II
The estimate of the parameter vector can be obtained by maximizing the log-likelihood function
where is defined according to one of the two types of hyberbolastic functions used.
The multinomial hyperbolastic regression of type I and II
The generalization of the binary hyperbolastic regression to multinomial hyperbolastic regression has a response variable for individual with categories (i.e. ). When , this model reduces to a binary hyperbolastic regression.
For each , we form indicator variables where
,
meaning that whenever the response is in category and otherwise.
Define parameter vector in a -dimensional Euclidean space and .
Using category 1 as a reference and as its corresponding probability function, the multinomial hyperbolastic regression of type I probabilities are defined as
and for ,
Similarly, for the multinomial hyperbolastic regression of type II we have
and for ,
where with and .
The choice of is dependent on the choice of hyperbolastic H1 or H2.
Shannon Information for multiclass hyperbolastic H1 or H2
For the multiclass , the Shannon information is
.
For a random sample of size , the empirical multiclass information can be estimated by
.
Multiclass Entropy in Information Theory
For a discrete random variable , the multiclass information entropy is defined as
where is the probability mass function for the multiclass random variable .
For the hyperbolastic H1 or H2, the multiclass entropy is equal to
The estimated average multiclass entropy is equal to
Multiclass Cross-entropy for hyperbolastic H1 or H2
Multiclass cross-entropy compares the observed multiclass output with the predicted probabilities. For a random sample of multiclass outcomes of size , the average multiclass cross-entropy for hyperbolastic H1 or H2 can be estimated by
The log-odds of membership in category versus the reference category 1, denoted by , is equal to
where and . The estimated parameter matrix of multinomial hyperbolastic regression is obtained by maximizing the log-likelihood function. The maximum likelihood estimates of the parameter matrix is
References
Medical models
Population models
Special functions | Hyperbolastic functions | [
"Mathematics"
] | 2,619 | [
"Special functions",
"Combinatorics"
] |
63,442,121 | https://en.wikipedia.org/wiki/Benjamin%20Franklin%20Drawing%20Electricity%20from%20the%20Sky | Benjamin Franklin Drawing Electricity from the Sky is a c. 1805 painting by Benjamin West in the Philadelphia Museum of Art. It depicts American Founding Father Benjamin Franklin conducting his kite experiment in 1752 to ascertain the electrical nature of lighting. West composed his work using oil on a slate. The painting blends elements of both Neoclassicism and Romanticism. Franklin knew West, which influenced the creation of this painting.
Background
West based his painting on a well-known experiment Franklin conducted in 1752. Franklin observed that lightning frequently destroyed homes by igniting those made of wood. Franklin was determined to prove the presence of electricity in lightning through an experiment. Franklin's experiment, in its initial conception, depended on the completion of Christ Church in Philadelphia, whose steeples would be sufficiently high as to attract a lightning strike. Franklin then conceived of an alternative experiment that involved flying a kite during a thunderstorm with a metal key attached to the string.
Franklin conducted his experiment in private for several reasons, including its dangerous nature, and he did not want to disappoint the scientific community if the experiment failed. He decided to experiment alongside his son William in a field. Franklin demonstrated that the clouds carried an electrical charge by bringing a finger near the metal key, producing a spark. His experiments led to the widespread adoption of lightning rods on tall buildings to draw electricity off the building and into the ground.
Description and interpretation
Painting
Franklin is pictured raising his hand into the stormy skies as the clouds open above him. A spark appears between the key and Franklin's hand. West depicts Franklin with white hair, as he is popularly remembered. He holds a scroll in his left hand and is wearing a red cloak that is blowing in the wind.
To Franklin's right is a group of cherubs assisting him in his experiment by holding the kite string and observing him. West dresses one of these cherubs in traditional Native American attire. Cherubs were traditionally used in Apotheosis paintings that deify humans. Directly to Franklin's right is another group of cherubs tinkering with a tool. Franklin's right arm, the Cherub to his right, and the Cherub to his left, come together to form a triangle, the compositional foundation of the entire painting. The arrangement directs the viewers' eyes to Franklin's hand and the lightning key. West amplifies this effect by clearly defining the edges of the key and making the surrounding electricity more pronounced than the lighting in the distance. Franklin's head and gaze are fixated upwards looking beyond the canvas towards the heavens. These elements suggest that Franklin calls on the forces on nature and the heavens in his experiment.
West includes elements commonly used in Romantic paintings, such as religious motifs and sublime aesthetics. However, the cherubs and themes of masculine heroism are more characteristic of Neoclassical paintings. The blend of two styles allows West to combine intelligibility with a sense of mystery.
Straying from the truth
The painting is an example of a history painting, but as West had done in the past with works such as in his 1770 The Death of General Wolfe, he strays from the truth and embellishes many elements for added dramatic effect. Franklin was in his forties and with his son when he conducted the experiment, but West paints him with white hair and wrinkly as an elderly man. West adds cherubs and other dramatic elements to depict Franklin as Prometheus-like figure, who stands as an American hero of scientific discovery. Other works of art, such as Carl Rohl-Smith's Statue of Young Benjamin Franklin with Kite, provide a more accurate representation of Franklin at the time of his experiment, giving him a significantly younger appearance.
West's relationship with Franklin
West and Franklin initially met in London, then developed an amicable relationship as fellow Philadelphians. West was born in Swarthmore, Pennsylvania, and Franklin moved to Pennsylvania in his early adulthood. They became close enough that West asked Franklin to be godfather to his second son. West decided to make the painting to celebrate the achievements of his friend after Franklin's death. The painting was intended to be a study for a much larger painting that West planned to donate in honor of his friend to the Philadelphia Hospital, established by Franklin.
In modern culture
In 1965 the United States selected this painting to be featured on their memorial postage stamp commemorating the 250 anniversary of Benjamin Franklin's birth.
See also
Franklin's electrostatic machine
Lightning rod
References
1810s paintings
Cultural depictions of Benjamin Franklin
Lightning
Paintings in the Philadelphia Museum of Art
Science in art
Paintings by Benjamin West
Paintings of children | Benjamin Franklin Drawing Electricity from the Sky | [
"Physics"
] | 935 | [
"Physical phenomena",
"Electrical phenomena",
"Lightning"
] |
63,442,371 | https://en.wikipedia.org/wiki/Regulation%20of%20algorithms | Regulation of algorithms, or algorithmic regulation, is the creation of laws, rules and public sector policies for promotion and regulation of algorithms, particularly in artificial intelligence and machine learning. For the subset of AI algorithms, the term regulation of artificial intelligence is used. The regulatory and policy landscape for artificial intelligence (AI) is an emerging issue in jurisdictions globally, including in the European Union. Regulation of AI is considered necessary to both encourage AI and manage associated risks, but challenging. Another emerging topic is the regulation of blockchain algorithms (Use of the smart contracts must be regulated) and is mentioned along with regulation of AI algorithms. Many countries have enacted regulations of high frequency trades, which is shifting due to technological progress into the realm of AI algorithms.
The motivation for regulation of algorithms is the apprehension of losing control over the algorithms, whose impact on human life increases. Multiple countries have already introduced regulations in case of automated credit score calculation—right to explanation is mandatory for those algorithms. For example, The IEEE has begun developing a new standard to explicitly address ethical issues and the values of potential future users. Bias, transparency, and ethics concerns have emerged with respect to the use of algorithms in diverse domains ranging from criminal justice to healthcare—many fear that artificial intelligence could replicate existing social inequalities along race, class, gender, and sexuality lines.
Regulation of artificial intelligence
Public discussion
In 2016, Joy Buolamwini founded Algorithmic Justice League after a personal experience with biased facial detection software in order to raise awareness of the social implications of artificial intelligence through art and research.
In 2017 Elon Musk advocated regulation of algorithms in the context of the existential risk from artificial general intelligence. According to NPR, the Tesla CEO was "clearly not thrilled" to be advocating for government scrutiny that could impact his own industry, but believed the risks of going completely without oversight are too high: "Normally the way regulations are set up is when a bunch of bad things happen, there's a public outcry, and after many years a regulatory agency is set up to regulate that industry. It takes forever. That, in the past, has been bad but not something which represented a fundamental risk to the existence of civilisation."
In response, some politicians expressed skepticism about the wisdom of regulating a technology that is still in development. Responding both to Musk and to February 2017 proposals by European Union lawmakers to regulate AI and robotics, Intel CEO Brian Krzanich has argued that artificial intelligence is in its infancy and that it is too early to regulate the technology. Instead of trying to regulate the technology itself, some scholars suggest to rather develop common norms including requirements for the testing and transparency of algorithms, possibly in combination with some form of warranty. One suggestion has been for the development of a global governance board to regulate AI development. In 2020, the European Union published its draft strategy paper for promoting and regulating AI.
Algorithmic tacit collusion is a legally dubious antitrust practise committed by means of algorithms, which the courts are not able to prosecute. This danger concerns scientists and regulators in EU, US and beyond. European Commissioner Margrethe Vestager mentioned an early example of algorithmic tacit collusion in her speech on "Algorithms and Collusion" on March 16, 2017, described as follows:
"A few years ago, two companies were selling a textbook called The Making of a Fly. One of those sellers used an algorithm which essentially matched its rival’s price. That rival had an algorithm which always set a price 27% higher than the first. The result was that prices kept spiralling upwards, until finally someone noticed what was going on, and adjusted the price manually. By that time, the book was selling – or rather, not selling – for 23 million dollars a copy."
In 2018, the Netherlands employed an algorithmic system SyRI (Systeem Risico Indicatie) to detect citizens perceived being high risk for committing welfare fraud, which quietly flagged thousands of people to investigators. This caused a public protest. The district court of Hague shut down SyRI referencing Article 8 of the European Convention on Human Rights (ECHR).
In 2020, algorithms assigning exam grades to students in the UK sparked open protest under the banner "Fuck the algorithm." This protest was successful and the grades were taken back.
Implementation
AI law and regulations can be divided into three main topics, namely governance of autonomous intelligence systems, responsibility and accountability for the systems, and privacy and safety issues. The development of public sector strategies for management and regulation of AI has been increasingly deemed necessary at the local, national, and international levels and in fields from public service management to law enforcement, the financial sector, robotics, the military, and international law. There are many concerns that there is not enough visibility and monitoring of AI in these sectors. In the United States financial sector, for example, there have been calls for the Consumer Financial Protection Bureau to more closely examine source code and algorithms when conducting audits of financial institutions' non-public data.
In the United States, on January 7, 2019, following an Executive Order on 'Maintaining American Leadership in Artificial Intelligence', the White House's Office of Science and Technology Policy released a draft Guidance for Regulation of Artificial Intelligence Applications, which includes ten principles for United States agencies when deciding whether and how to regulate AI. In response, the National Institute of Standards and Technology has released a position paper, the National Security Commission on Artificial Intelligence has published an interim report, and the Defense Innovation Board has issued recommendations on the ethical use of AI.
In April 2016, for the first time in more than two decades, the European Parliament adopted a set of comprehensive regulations for the collection, storage, and use of personal information, the General Data Protection Regulation (GDPR)1 (European Union, Parliament and Council 2016).[6] The GDPR's policy on the right of citizens to receive an explanation for algorithmic decisions highlights the pressing importance of human interpretability in algorithm design.
In 2016, China published a position paper questioning the adequacy of existing international law to address the eventuality of fully autonomous weapons, becoming the first permanent member of the U.N. Security Council to broach the issue, and leading to proposals for global regulation. In the United States, steering on regulating security-related AI is provided by the National Security Commission on Artificial Intelligence.
In 2017, the U.K. Vehicle Technology and Aviation Bill imposes liability on the owner of an uninsured automated vehicle when driving itself and makes provisions for cases where the owner has made “unauthorized alterations” to the vehicle or failed to update its software. Further ethical issues arise when, e.g., a self-driving car swerves to avoid a pedestrian and causes a fatal accident.
In 2021, the European Commission proposed the Artificial Intelligence Act.
Algorithm certification
There is a concept of algorithm certification emerging as a method of regulating algorithms. Algorithm certification involves auditing whether the algorithm used during the life cycle 1) conforms to the protocoled requirements (e.g., for correctness, completeness, consistency, and accuracy); 2) satisfies the standards, practices, and conventions; and 3) solves the right problem (e.g., correctly model physical laws), and satisfies the intended use and user needs in the operational environment.
Regulation of blockchain algorithms
Blockchain systems provide transparent and fixed records of transactions and hereby contradict the goal of the European GDPR, which is to give individuals full control of their private data.
By implementing the Decree on Development of Digital Economy, Belarus has become the first-ever country to legalize smart contracts. Belarusian lawyer Denis Aleinikov is considered to be the author of a smart contract legal concept introduced by the decree. There are strong arguments that the existing US state laws are already a sound basis for the smart contracts' enforceability — Arizona, Nevada, Ohio and Tennessee have amended their laws specifically to allow for the enforceability of blockchain-based contracts nevertheless.
Regulation of robots and autonomous algorithms
There have been proposals to regulate robots and autonomous algorithms. These include:
the South Korean Government's proposal in 2007 of a Robot Ethics Charter;
a 2011 proposal from the U.K. Engineering and Physical Sciences Research Council of five ethical “principles for designers, builders, and users of robots”;
the Association for Computing Machinery's seven principles for algorithmic transparency and accountability, published in 2017.
In popular culture
In 1942, author Isaac Asimov addressed regulation of algorithms by introducing the fictional Three Laws of Robotics:
A robot may not injure a human being or, through inaction, allow a human being to come to harm.
A robot must obey the orders by human beings except where such orders would conflict with the First Law.
A robot must protect its own existence as long as such protection does not conflict with the First or Second Laws.
The main alternative to regulation is a ban, and the banning of algorithms is presently highly unlikely. However, in Frank Herbert's Dune universe, thinking machines is a collective term for artificial intelligence, which were completely destroyed and banned after a revolt known as the Butlerian Jihad:
JIHAD, BUTLERIAN: (see also Great Revolt) — the crusade against computers, thinking machines, and conscious robots begun in 201 B.G. and concluded in 108 B.G. Its chief commandment remains in the O.C. Bible as "Thou shalt not make a machine in the likeness of a human mind."
See also
Algorithmic transparency
Algorithmic accountability
Artificial intelligence
Artificial intelligence arms race
Artificial intelligence in government
Ethics of artificial intelligence
Government by algorithm
Privacy law
References
Computer law
Existential risk from artificial general intelligence
Algorithms
Blockchains
Regulation of technologies
Regulation of artificial intelligence | Regulation of algorithms | [
"Mathematics",
"Technology"
] | 1,983 | [
"Existential risk from artificial general intelligence",
"Regulation of artificial intelligence",
"Algorithms",
"Mathematical logic",
"Applied mathematics",
"Computer law",
"Computing and society"
] |
63,445,151 | https://en.wikipedia.org/wiki/FU%20Tauri | FU Tauri is a brown dwarf binary system in the constellation of Taurus about away. The secondary is very close to the lower limit for brown dwarfs and several databases list it as a distant massive exoplanet.
System
The two stars of the FU Tauri system are separated by , equivalent to at the distance of FU Tauri. The primary is a brown dwarf with a mass of , while the secondary has a mass of . The secondary mass of is close to the dividing line between brown dwarfs and exoplanets, and it is often treated as an exoplanet.
Properties
Both members of the binary are low-mass objects still contracting towards the main sequence. Comparison with theoretical evolutionary tracks gives them ages of one Myr or less. However, the primary is more luminous than expected even for this age and it may be younger than the secondary. The primary has a temperature of , a radius of , and a bolometric luminosity of . The secondary has a temperature of and a bolometric luminosity of .
Variability
FU Tauri varies in brightness. The primary star is a T Tauri variable, a type of irregular pre-main-sequence star. Its brightness has been observed to vary from a photovisual magnitude of 16.0 to fainter than 17.0. Its photographic magnitude has been measured to vary between magnitude 15.1 and below magnitude 17.6.
References
Brown dwarfs
T Tauri stars
Taurus (constellation)
J04233539+2503026
Tauri, FU
Binary stars
M-type brown dwarfs
Planetary systems with one confirmed planet | FU Tauri | [
"Astronomy"
] | 327 | [
"Taurus (constellation)",
"Constellations"
] |
63,445,194 | https://en.wikipedia.org/wiki/NGC%20825 | NGC 825 is an unbarred spiral galaxy in the constellation Cetus, estimated to be 154 million light-years away. The object was discovered by the astronomer Albert Marth on November 18, 1863.
See also
List of NGC objects (1–1000)
References
External links
Unbarred spiral galaxies
0825
Cetus
008173 | NGC 825 | [
"Astronomy"
] | 71 | [
"Cetus",
"Constellations"
] |
63,446,562 | https://en.wikipedia.org/wiki/Impact%20of%20the%20COVID-19%20pandemic%20on%20social%20media | Social media became an important platform for interaction during the COVID-19 pandemic, coinciding with the onset of social distancing. According to a study conducted by Facebook's analytics department, messaging rates rose by over 50% during this period. Individuals confined to their homes utilized social media not only to maintain social connections but also as a source of entertainment to alleviate boredom. Concerns arose regarding the overreliance on social media for primary social interactions, particularly given the constraints imposed by the pandemic.
People worldwide turned to social networking services to disseminate information, find humor through internet memes, and cope with the challenges of social distancing. The shift to virtual interactions exacerbated mental health issues to many, prompting the rapid rise of online counselling that leveraged social media platforms to connect mental health workers with those in need.
The COVID-19 pandemic highlighted the phenomenon of misinformation on social media, often referred to as an "infodemic." Platforms like Twitter and YouTube provided direct access to content, making users susceptible to rumors and unreliable information that could significantly impact individual behaviors and undermine collective efforts against the virus. Furthermore, social media became crucial for politicians, political movements, and health organizations at various levels to disseminate critical information swiftly and effectively reach the public.
Increase in usage
Messaging and video call services
Multiple social media websites reported a sharp increase in usage after social distancing measures were put into place. Since many people could not connect with their friends and family in person, social media became the main form of communication to maintain these connections. For example, the amount of Facebook users went up to about 1.9 billion worldwide by the end of 2020, marking an 8.7% increase over 2019. Meanwhile, WhatsApp has reported a 40% percent increase in usage overall. Moreover, there was a noticeable increase in the use of Zoom since the start of the pandemic. Global downloads for TikTok went up 5% in March 2020 compared to February. A new service called Quarantine Chat, which connected users randomly, reported having over 15,000 users a month after its launch on 1 March 2020. Zoom also followed a similar procedure to connect users.
Facebook, Twitter, and YouTube have all increased reliance on spam filters because staff members who moderate content were unable to work.
Online counseling services
Particularly in countries where the virus had a greater impact, online mental health services received a surge in demand, as COVID-19 social distancing obstructed patients from meeting with therapists or psychologists in person. In China, medical staff used social media programs like WeChat, Weibo, and TikTok to roll out online mental health education programs. In Canada, the provincial government of Alberta launched a $53 million COVID-19 mental health response plan, which included increasing accessibility to phone and online support with existing helplines. Additionally, the Canadian province of Ontario's government provided emergency funding of up to $12 million to expand online and virtual mental health support.
Effect of COVID-19 on mental health
There is an extensive psychology research proving that connectivity with others develops a sense of belonging and psychosocial well-being, which enhances mental health and reduces the risk of anxiety and depression. The overload of information and the constant use of social media have been shown to positively correlate with an increase in depression and anxiety, yet also with improvement in communication skills. The impact of following social distancing measures can cause feelings of loneliness and isolation in people, increasing anxiety and stress. Many adults are also reporting specific negative impacts on their mental health and well-being, such as difficulty sleeping (60%) or eating (80%), increases in alcohol consumption or substance abuse (50%), and worsening of chronic conditions (35%), due to worry and stress over education and employment conditions. While being part of a global pandemic can be stressful and cause anxiety, there are ways you can support yourself and your family.
Effect of COVID-19 on face-to-face communication
The increased use of face masks makes interpretation during face-to-face contact much more challenging because masks hide a large portion of the face, posing difficulties in reading basic communication signals like intention and emotion. Wearing a face mask causes individuals to focus on oral cues, leading to potential mistrust, misinterpretation, linguistic misunderstandings, and difficulties in comprehension. Alongside the disconnection caused by face masks, social distancing, and self-isolation, there are risks of increased social rejection, growing impersonality, individualism, and a loss of community. Data suggests that the implementation of face masks, increased social distancing, and self-isolation present challenges in fostering positive interpersonal relationships and a sense of community.
The new COVID-19 pneumonia epidemic has significantly affected the way people communicate with each other. Preventive measures to limit the spread of the virus require changes in communication patterns regarding greetings and handshakes. This situation has prompted people to adopt greetings that do not require physical contact, such as "peaceful gestures" and "hands on the chest". Additionally, telecommunications has seen a notable emphasis on personal space and social distance as business meetings, conferences, and educational activities shift to virtual communication through platforms like Zoom, Cisco WebEx, Skype, and Microsoft Teams.
Effect of COVID-19 on online businesses
The COVID-19 pandemic forced many businesses to shut down or implement remote work, leading to significant layoffs. Families were confined to home in self-isolation and quarantine as effective measures to prevent the spread of COVID-19. Since the start of the pandemic, many businesses have experienced a drastic increase in online orders. Those facing declining sales had to adapt to new consumer spending habits.
Effects of COVID-19 on visual arts
Global shutdowns compelled artists, museums, and galleries to explore new ways to engage with the public. The Getty Museum initiated a social media challenge encouraging users to recreate artworks from their collection using household items and share the results online. Galleries like David Zwirner moved scheduled exhibits to virtual spaces. Artist Benjamin Cook's Social Distance Gallery used Instagram to host mini thesis exhibitions for students worldwide who had their graduation shows cancelled.
Increased engagement
A study of people's internet and social media engagement from July 2019 to 2020 indicated a 10.5% increase in active social media users. Instagram reported a 70% surge in viewership of live videos from February to March when lockdown measures began. Another study conducted in July, four months after the initial COVID-19 lockdowns, surveyed individuals on their primary reasons for using social media and other connectivity technologies. Eighty-three percent of respondents stated that social media helped them cope with COVID-19-related lockdowns. This response was the highest, surpassing other reasons such as education (76%), staying in touch with friends and family (74%), and work-related activities (67%). It underscores the crucial role of social media in people's lives during the pandemic.
Due to the pandemic, people reduced their social activities to safeguard others. Students transitioned to online learning, with many relying on social media as a new study tool. Researchers have identified both advantages and disadvantages of using social media for studying. UNESCO reported that school closures affecting 890 million students across 114 countries disrupted traditional education. Social media became indispensable for students during the pandemic, providing an effective means to collaborate and develop skills while at home. For instance, collaborating with peers on social media enables students to learn communication and teamwork skills as they work together to solve problems.
Use as entertainment
During the pandemic, numerous Internet memes emerged related to the COVID-19 situation. One notably popular Facebook group among young people, predominantly Generation Z, was "Zoom Memes for Self Quaranteens." This group humorously played on the pun of increased Zoom usage and self-quarantine among teenagers, amassing over 500,000 members as of April 2020. Members shared and created memes about the pandemic, providing entertainment for many young people who had transitioned to online schooling and needed ways to pass the time and cope with the situation.
Various social media challenges also gained traction during this period, serving to connect individuals and provide entertainment. One such example was the See10Do10 challenge, where participants performed and recreated 10 push-ups. Other challenges included sharing baby photos, participating in dance challenges, and voting in candy and chocolate March Madness bracket polls. Additionally, the V-pop hit "Ghen" by artists Erik and Men was remixed by lyricists Khắc Hưng to create "Ghen Cô Vy," which supported Vietnam's National Institute of Occupational Safety and Health with a song encouraging handwashing. The song went viral after dancer Quang Đăng posted a dance to it on TikTok, sparking the #GhenCoVyChallenge.
Teens also used TikTok to create videos sharing their experiences in quarantine, using humour to relate to their peers and keep themselves entertained. From January to March 2020, TikTok experienced a 48.3% increase in unique visitors.
Makeup artists on YouTube adapted their content to showcase makeup looks that accommodate mask-wearing during the pandemic.
In April, The Actors Fund organized a charity livestream of The Phantom of the Opera performance from London's Royal Albert Hall, which raised funds over 48 hours. Similarly, Phoebe Waller-Bridges's stage performance of Fleabag was streamed for charity and entertainment purposes Authors, musicians, actors, actresses, and dancers collaborated on numerous concerts, live streams of past productions, readings, and performances that were either free or required an entrance fee or suggested charitable donation.
Spreading information
Social media has been used by news outlets, organizations, and the general public to disseminate both accurate information and misinformation about the pandemic. The CDC, WHO, medical journals, and healthcare organizations have been actively updating and sharing information across various platforms, often partnering with Facebook, Google Scholar, TikTok, and Twitter. Additionally, frontline healthcare professionals, such as emergency medicine physicians in New York hospitals, have utilized their social media accounts to provide firsthand accounts of combating COVID-19. A social listening study conducted from January 1 to March 19 indicated a significant increase in COVID-19-related conversations, with a 1,000% rise among healthcare professionals and a 2,500% increase among consumers. Despite hypotheses that increased public discourse and research would enhance trust in science during the pandemic, early studies reported null findings.
Accurate and reliable information disseminated through social media platforms plays a crucial role in combatting infodemics, misinformation, and rumors related to COVID-19. An article in The Lancet stated that real-time surveillance via social media can also serve as a valuable tool for public health agencies and organizations in implementing effective interventions.
Medical professionals have formed groups on social media to share information and insights on treating COVID-19. For instance, the PMG COVID-19 Subgroup on Facebook had approximately 30,000 members globally by the end of March, while the Physician Moms Group, established five years prior to the pandemic, experienced such high demand that Facebook's join feature temporarily malfunctioned.
Healthcare workers have used social media to educate the public about the challenges of wearing personal protective equipment (PPE) for extended shifts. Many participated in trends showcasing their faces post-shift, revealing marks and injuries caused by prolonged mask use.
Government use of social media
Governments have utilized social media extensively during the pandemic. The Chinese government, for example, has employed social media to disseminate scientific information about COVID-19 in accessible language to aid public understanding. In contrast, Australian health authorities have focused less on platforms popular among younger demographics, such as Instagram and TikTok, when sharing COVID-19 information. esearchers argue that effective governmental use of social media can mitigate public panic and contribute to societal stability. Governments should take proactive measures to communicate effectively on social media using language that resonates with the public, thereby reducing the spread of misinformation and fostering social stability based on evidence-backed information.
Role of World Health Organization and other international organizations
The COVID-19 pandemic significantly amplified the World Health Organizations (WHO) utilization of social media. In response to the declaration of COVID-19 as a Public Health Emergency, the WHO Information Network for Epidemics was established. This platform, staffed by 20 individuals, is dedicated to providing evidence-based responses to counteract rumours circulating across various social media platforms. It ensures that searches related to "coronavirus" on social media and Google direct users to reliable information sources such as the WHO website or the Centers for Disease Control and Prevention.
In April 2020, the United Nations launched the United Nations Communications Response initiative aimed at curbing the spread of misinformation during the pandemic. This initiative sought to mitigate hate speech and prevent disinformation from exacerbating political divisions online. Additionally, on 11 May 2020, the United Nations issued a Guidance Note on Addressing and Countering COVID-19-related Hate Speech, further targeting misinformation challenges online.
Limitations in the use of social media to spread information
Social media platforms do not uniformly impact all demographics. Older age groups often do not utilize social media as extensively as younger populations, preferring traditional communication channels. Approximately 69% of individuals aged 50 to 64 engage with some form of social media, highlighting the necessity to devise alternative methods to reach the remaining 31% of this demographic.
Social media lack editorial oversight. Unlike peer-reviewed publications, there is no mandatory peer review process for content posted online, contributing to the proliferation of misinformation. Although social media platforms employ fact-checking teams, it remains impractical to manually verify every piece of content posted across these platforms.
Misinformation
The COVID-19 pandemic has been characterized as the first major "social-media infodemic" by MIT Technology Review, highlighting social media's pivotal role as the primary source of information and communication during this period. National Geographic reported a surge in "fake animal news" circulated on social media platforms during the pandemic. Research indicates a significant shift in information consumption patterns, with many individuals increasingly relying on social media over traditional search engines and browsers, thereby influencing behaviors and potentially undermining government response efforts to the virus.
There is preliminary evidence suggesting that public trust in science and scientists may influence the perceived credibility of COVID-19 misinformation. However, caution is advised in interpreting these findings pending further study.
Social media platforms, including Twitter, have become crucial channels for news updates, although concerns persist regarding the proliferation of misinformation disseminated through automated “bot” accounts. The challenge of distinguishing reliable information sources from misinformation has contributed to varying levels of skepticism and distrust among users.
Misinformation varies widely across countries and can be disseminated intentionally or inadvertently, exacerbating the severity of the pandemic.
The algorithms behind some social platforms may have inadvertently facilitated the spread of misinformation. This was due to increased AI usage when many human moderators were unable to work remotely during shelter in place orders or faced contractual restrictions, which compromised their ability to effectively manage content and prevent the dissemination of COVID-19 misinformation.
Fox News reported instances where social media groups spread rumors opposing vaccines and campaigning against 5G mobile phone networks. For example, the Stop 5G French group on Facebook shared an article from BBC News claiming, "It is becoming pretty clear that the Hunan coronavirus is an engineered bio-weapon that was either purposely or accidentally released." These online rumors led to mob attacks in India, mass poisonings in Iran, and vandalism of phone masts in the United Kingdom.
Social media has become a primary source of misinformation during the pandemic. In China, misinformation spread through platforms like Messenger included false reports that fireworks could kill the virus in the air, and that vinegar and indigowoad root could cure infections. This misinformation resulted in panic-buying of supplies, depleting resources needed by professionals. Additionally, outdated claims, such as the reported benefits of Hydroxychloroquine, continued to circulate despite WHO ending trials due to safety concerns, potentially risking patient safety.
Misinformation and conspiracy theories related to COVID-19 have been flagged, removed, or restricted by Facebook and Instagram on their respective social media platforms. For instance, Facebook has taken measures to curb false claims about cures and prevention methods. However, the efficacy of Facebook's third-party fact-checkers in limiting the spread of false content by notifying and providing accurate information to users remains varied.
A study conducted in May 2021 identified that a small number of individuals were responsible for a significant portion (85%) of false information surrounding COVID-19 vaccines circulating on social media, prompting actions such as content blocking for some of these prolific disseminators, colloquially known as the "Disinformation Dozen."
Older adults are often exposed to misinformation on social media platforms. Research by the WHO indicates that over half (59.1%) of those surveyed are aware of and can recognize COVID-19-related fake news. Consequently, misinformation significantly impacts young people as well, with 60.1% reportedly disregarding false information encountered on social media. Addressing this challenge not only involves helping individuals identify misinformation but also mobilizing efforts to actively counter and mitigate its effects.
Usage by celebrities
Throughout the pandemic, many celebrities utilized social media platforms to engage with their fan bases and address the challenging circumstances through various means, including posts, acts of kindness, or participation in trends. Some celebrities faced swift public criticism for their posts, such as Gwyneth Paltrow, who deleted an Instagram post showcasing designer fashion, and Jared Leto, who sparked controversy with a Twitter post emerging 12-day silent meditation isolation in the desert. Similarly, Ellen DeGeneres and Gal Gadot received backlash for their social media activities, with DeGeneres criticized for comments about quarantine life in her California mansion, and Gadot for organizing a celebrity rendition of John Lennon's "Imagine."
Several celebrities or their family members also used social media to announce their positive COVID-19 diagnoses, including Tom Hanks and Rita Wilson, Idris Elba, and Daniel Dae Kim used his platform to highlight donating plasma containing active antibodies to a Vitalant blood donation center, potentially aiding others affected by the virus. Notably, a controversial Instagram post by K-Pop Star Kim Jae-joong, claiming a COVID-19 hospitalization later revealed as an April Fools' Day Prank, aimed to raise awareness about the pandemic.
Moreover, celebrities leveraged social media to promote charitable action during the pandemic. For instance, Ansel Elgort used his Instagram platform creatively, drawing attention to a GoFundMe campaign by actor Jeffrey Wright aimed at feeding frontline workers, albeit initially raising eyebrows with a provocative post captioned "OnlyFans LINK IN BIO."
Usage by world leaders
On 7 April 2020, former U.S. President Donald Trump utilized Twitter and the #AmericaWorksTogether hashtag to highlight companies aiding in mitigating the economic impacts of the virus by hiring employees and supplying health workers with necessary equipment.
Queen Elizabeth II and other members of the British royal family have also used social media to communicate with the public. Comments from the Queen were shared on the royal family's Instagram account, and in the lead-up to V-E Day, information based on the Queen's memories from a 1985 interview was posted on Instagram. Several royal family members participated in Zoom calls with nurses to commemorate International Nurses Day, which subsequently posted on their YouTube page. Prince William and Catherine Middleton allowed their Instagram account to be "taken over" for 24-hours by Shout85258, the UK's first 24/7 crisis text line they launched with Prince Harry and Meghan Markle in May 2019. The Dutch royal family used their Instagram account to share a video of King Willem-Alexander, Queen Máxima and their teenage daughters clapping for first responders, accompanied by a brief speech by the King.
Censorship
In Turkey, more than 400 individuals were arrested for posting "provocative" messages about the pandemic on social media. Chinese social media networks, such as WeChat have reportedly censored terms related to the pandemic since 31 December 2019. Notably, Dr. Li Wenliang was censored by the Wuhan police for posting about the pandemic in a private group chat. Doctors in China were instructed by local authorities to delete social media posts appealing for donations of medical supplies.
NetBlocks, a civil society group advocating for digital rights, cybersecurity, and Internet governance, reported internet outages in Wuhan during the pandemic. They also noted that the Farsi version of Wikipedia was blocked for 24 hours in Iran. The VPN company Surfshark reported a roughly 50% drop-off in its network usage in Iran after the pandemic was declared on 13 March by the WHO.
In an August 2024 letter to the American House Judiciary committee, Meta chairman Mark Zuckerberg wrote "In 2021, senior officials from the Biden Administration, including the White House, repeatedly pressured our teams for months to censor certain COVID-19 content, including humor and satire" and continued that "[he feels] strongly that we should not compromise our content standards due to pressure from any Administration in either direction – and we’re ready to push back if something like this happens again".
References
External links
Coronavirus misinformation on social media, CBS News
How to spot fake coronavirus news on social media, Los Angeles Times
2020 in Internet culture
COVID-19 pandemic in popular culture
Internet memes related to the COVID-19 pandemic
Social media | Impact of the COVID-19 pandemic on social media | [
"Technology"
] | 4,574 | [
"Computing and society",
"Social media"
] |
63,446,954 | https://en.wikipedia.org/wiki/Acyline | Acyline (developmental code name MER-104) is a gonadotropin-releasing hormone analogue (GnRH analogue) and gonadotropin-releasing hormone antagonist (GnRH antagonist) which was never marketed. It has been shown to suppress gonadotropin and testosterone levels in men. Acyline is a peptide and under normal circumstances is not orally active. For this reason, it has instead been administered by subcutaneous injection.
See also
Gonadotropin-releasing hormone receptor § Antagonists
References
Abandoned drugs
GnRH antagonists
Peptides | Acyline | [
"Chemistry"
] | 123 | [
"Biomolecules by chemical classification",
"Drug safety",
"Abandoned drugs",
"Peptides",
"Molecular biology"
] |
63,447,176 | https://en.wikipedia.org/wiki/Dissimilatory%20sulfite%20reductase | Dissimilatory sulfite reductase () is an enzyme that participates in sulfur metabolism in dissimilatory sulfate reduction.
The enzyme is essential in prokaryotic sulfur-based energy metabolism, including sulfate/sulfite reducing organisms, sulfur-oxidizing bacteria, and organosulfonate reducers. In sulfur reducers it catalyses the reduction of sulfite to sulfide (reaction 1), while in sulfur oxidizers it catalyses the opposite reaction (reaction 2). The reaction involves the small protein DsrC, which is present in all the organisms that contain dissimilatory sulfite reductase. During the process an intramolecular trisulfide is formed between two L-cysteine residues of DsrC and the sulfur atom from sulfite. This trisulfide can be reduced by a number of proteins including DsrK and TcmB.
Reaction in organisms performing dissimilatory sulfate reduction:
(1) sulfite + a [DsrC protein]-dithiol + 2 reduced acceptor + 2 H+ = hydrogen sulfide + a [DsrC protein]-disulfide + 2 acceptor + 3 H2O (overall reaction)
(1a) sulfite + a [DsrC protein]-dithiol + 2 reduced acceptor + 2 H+ = a [DsrC protein]-S-sulfanyl-L-cysteine + 2 acceptor + 3 H2O
(1b) a [DsrC protein]-S-sulfanyl-L-cysteine = hydrogen sulfide + a [DsrC protein]-disulfide
Reaction in organisms performing sulfur oxidation:
(2) a [DsrC protein]-S-sulfanyl-L-cysteine + 3 acceptor + 3 H2O = sulfite + a [DsrC protein]-disulfide + 3 reduced acceptor + 2 H+ (overall reaction)
(2a) a [DsrC protein]-S-sulfanyl-L-cysteine + 3 acceptor + 3 H2O = a [DsrC]-S-sulfo-L-cysteine + 3 reduced acceptor + H+
(2b) a [DsrC]-S-sulfo-L-cysteine = sulfite + a [DsrC protein]-disulfide
The systematic name of this enzyme class is hydrogen-sulfide:[DsrC sulfur-carrier protein],acceptor oxidoreductase.
This enzyme is different from EC 1.8.1.2, assimilatory sulfite reductase (NADPH), and EC 1.8.7.1, assimilatory sulfite reductase (ferredoxin), which are involved in sulfate assimilation.
References
EC 1.8.99
Iron enzymes
Sulfur metabolism | Dissimilatory sulfite reductase | [
"Chemistry"
] | 608 | [
"Sulfur metabolism",
"Metabolism"
] |
63,447,442 | https://en.wikipedia.org/wiki/Present%20weather%20sensor | The present weather sensor (PWS) is a component of an automatic weather station that detects the presence of hydrometeors and determines their type (rain, snow, drizzle, etc.) and intensity. It works on a principle similar to a bistatic radar, noting the passage of droplets, or flakes, between a transmitter and a sensor. These instruments in automatic weather stations are used to simulate the observation taken by a human observer. They allow rapid reporting of any change in the type and intensity of precipitation, but include interpretation limitations.
Principle
Types
There are at least two types of devices used to detect precipitation:
A light emitting diode weather identifier (LEDWI) sensor measures the scintillation pattern of the precipitation falling through the sensor's infrared beam (approximately 50 millimeters in diameter) and determines from a pattern analysis of the particle size and fall velocity whether the precipitation is rain or snow.
The POSS (Precipitation Observation Sensor System) is a small bistatic Doppler radar. The transmitter aims upwards at a certain angle from a receiver oriented towards the volume probed and which picks up the signal backscattered by hydrometeors or other reflective particles in its detection volume. The device can thus measure the fall speed of targets by the Doppler effect and its intensity by its reflectivity. An analyzer then takes a weighted average of the last 15 polls over one minute to draw significant information.
Data processing
With the speed of fall and the size of the particles, it is then possible to determine the type of precipitation (rain falls much faster than snowflakes for example) with a contingency table. The detector will report the type of precipitation with the largest population in the samples. However, in some cases, the characteristics of two types of precipitation may be similar (drizzle and snow fall at speeds very close to each other), or there may be a mixture of precipitation (e.g. rain and melting snow).
To refine detection in the event of ambiguity, these devices use the dew point temperature (or, if missing, environmental temperature) and the icing detector output. Thus, if the detector identifies the falling speed for the dual snow/drizzle at an ambient dew point greater than it will classify it as drizzle, and below , it will be snow. The icing detector will also be used to determine if rain or drizzle is freezing when the temperature is below freezing.
When these additional data still do not make it possible to differentiate (e.g. if the dew point of the previous example is between −1 and 1 °C), the type is then reported as "unknown". Thus at the moment, these devices cannot report hail, ice pellets, and various other intermediate forms of precipitation.
The instantaneous intensity of precipitation is calculated by the intensity of the scintillation (LED sensor) or the reflectivity (POSS). It is reported as very weak, weak, moderate or strong.
Frequency of reporting
Automatic stations report on a regular schedule depending on their use, most reporting hourly. However, they will issue a special report if one or more of their sensors detects a significant change in weather conditions. Such specials are issued when precipitation of at least low intensity starts or stops, or the type of precipitation changes.
The present weather sensor takes samples every minute and the automatic station processing system stores them for 15 minutes. A special will be broadcast when at least three precipitation detections are made in 15 minutes for the start, if at least 12 minutes pass without precipitation, or if the intensity variation corresponds to a significant change.
Limitations
The detail of mixed precipitation is not generally possible as the sensor is giving only the dominant one. The report is only valid at the sensor position, it will thus miss precipitation further afield that can be significant. Finally, it cannot by itself distinguish showers from continuous rain/snow.
False observations of precipitation are generally due to:
Interference by radio frequency or light beams;
Birds or insects passing through the beam;
Blowing dust, snow or sand lifted by the wind;
Thermal bubbles.
Ambiguous situations where the contingency table cannot correctly determine the type.
Enhancements
Thundershowers and continuous precipitation can be separated by using a lightning detector with the sensor result. Ground-based and mobile detectors obtain the direction and severity of lightning.
Scatterometers and transmissometers, where the extinction of a visual signal through air from a source to a receiver is noted, will give the horizontal visibility. In case there is no precipitation reported by the PWS, this will be revert the conclusion to fog or haze.
References
Meteorological instrumentation and equipment | Present weather sensor | [
"Technology",
"Engineering"
] | 950 | [
"Meteorological instrumentation and equipment",
"Measuring instruments"
] |
74,941,968 | https://en.wikipedia.org/wiki/High%20anterior%20hairline | High anterior hairline is a dysmorphic feature in which the frontal hairline which defines the top and sides of the forehead is unusually high. This can mean that either the distance between the trichion (hairline) and glabella is more than 2 SD above the mean, or that this distance is apparently (subjectively) increased.
Conditions
High anterior hairline is seen in the following conditions and syndromes:
ADNP-related multiple congenital anomalies - intellectual disability - autism spectrum disorder
Alacrima, achalasia, and intellectual disability syndrome
Blepharophimosis - intellectual disability syndrome, MKB type
Cardiac malformation, cleft lip/palate, microcephaly, and digital anomalies
Coffin-Siris syndrome 12
Congenital disorder of glycosylation, type Iw, autosomal dominant
Congenital heart defects and ectodermal dysplasia
Curry-Jones syndrome
Developmental and epileptic encephalopathy, 83
Granulocytopenia with immunoglobulin abnormality
Intellectual developmental disorder with hypertelorism and distinctive facies
Intellectual developmental disorder, X-linked 108
Metaphyseal chondrodysplasia-retinitis pigmentosa syndrome
Neurodevelopmental disorder with hypotonia and brain abnormalities
Neurodevelopmental disorder with hypotonia and dysmorphic facies
Neurofacioskeletal syndrome with or without renal agenesis
Noonan syndrome 4
Orofacial cleft 15
SIN3A-related intellectual disability syndrome due to a point mutation
Singleton-Merten syndrome 1
See also
Hair loss
Low anterior hairline
References
Anatomical pathology
Hair
Face | High anterior hairline | [
"Biology"
] | 343 | [
"Organ systems",
"Hair"
] |
74,943,556 | https://en.wikipedia.org/wiki/Steven%20L.%20Goldstein | Steven L. Goldstein is an American geochemist. He is the Higgins Professor of Earth and Environmental Sciences at Columbia University and interim director of the Lamont–Doherty Earth Observatory.
Education
Goldstein received his B.A. from Columbia College in Chemistry with a minor in Philosophy. He earned his M.A. from Harvard University in the Department of Earth and Planetary Sciences.
Goldstein earned his PhD from Columbia University under the mentorship of Keith O’Nions. During this time, O’Nions moved from Columbia University to the University of Cambridge, but he continued to oversee Goldstein’s PhD. Goldstein’s thesis is titled, “Isotopic studies of continental and marine sediments, and igneous rocks of the Aleutian Island arc.” His other dissertation committee members included Alan Zindler, Charles Langmuir, Wallace Broecker, and Karl Turekian.
Career and Research
Upon completing his PhD, Goldstein was hired as a Staff Scientist at the Max Planck Institute for Chemistry from 1985-1996. In 1996, he joined the faculty in the Department of Earth and Environmental Sciences at Columbia University. He became an Associate Professor with tenure at Columbia University in 1998, Full Professor in 2005, and was named the Higgens Professor of Earth and Environmental Sciences in 2016. From 2006-2014, Goldstein held the roles of Associate Department Chair, Department Chair, and Past Chair in the Department of Earth and Environmental Sciences. He then became the Associate Director for the Geochemistry Division of the Lamont-Doherty Earth Observatory from 2014-2020. In 2020, Goldstein served as the Director of the Division of Earth Sciences for the National Science Foundation, ending the positing in 2022. In 2023 he was named the Interim Director of Lamont-Doherty Earth Observatory.
Goldstein is a professional member of the American Geophysical Union, European Association of Geochemistry, European Geophysical Union, Geochemical Society, and Geological Society of America. He has served on the Editorial Advisory Board of Chemical Geology (1990-2002) and Earth and Planetary Science Letters (1991-2004) and as an Associate Editor for the Journal of Geophysical Research: Solid Earth (1995-1997) and Geochimica et Cosmochimica Acta (2000-2002).
Research Focus
Goldstein’s research uses geochemistry, particularly naturally radioactive isotope systems, to understand the timing of events in Earth’s history and as tracers for fundamental Earth processes. His breadth of research applies geochemistry across time and space: from early Earth history to climate change, and from deep magmatism to ocean circulation.
As of 2023, Goldstein has published over 170 peer-reviewed articles and received over 10 million dollars in grant funding.
Field Work and Research Cruise Experience
While completing his MA at Harvard University, Goldstein attended a 6-week geology field camp through the University of Kansas based in Cañon City, CO. During his PhD, Goldstein conducted field work in South America and the Aleutian Islands, Alaska.
Since then, he has led field work across five continents. He served as Co-Principal Investigator on the 2001 AMORE (Arctic Mid-Ocean Ridge Expedition) research cruise aboard the Healey, during which he visited the North Pole. He also served as Co-Principal Investigator on the ICDP (International Continental Scientific Drilling Program) Dead Sea Deep Drilling Project, which recovered a continuous sedimentary record from the deepest seafloor of the Dead Sea.
Teaching and Public Scholarship
Goldstein strongly believes in the value of a humanities education alongside the sciences, a belief reflected in his work establishing the Frontiers of Science course within the Columbia University Core Curriculum. At Columbia University, he teaches popular undergraduate courses in the Department of Earth and Environmental Sciences that bridge the classroom and the field. This includes the introductory Earth Science course: “Earth’s Environmental Systems: The Solid Earth”. This course brings undergraduate students on a field trip to Central Park to convey that geology is everywhere, even among the skyscrapers of Manhattan. He uses the exposed rock outcrops to uncover 500 million years of Earth history, from the multiple cycles of Appalachian Mountain building to the glacial grooves and erratics of the last ice age. He also teaches a “Field Geology” class for majors, in which students attend a spring break field trip to Barbados and Italy.
He has also has given multiple public lectures, including “How Old is the Earth and How do we Know,” at venues such as Nevis Laboratories and Lamont-Doherty Earth Observatory Open House.
Awards and Honors
Goldstein was inducted as a fellow of the American Geophysical Union in 2009 and as a fellow of the Geochemical Society and European Association of Geochemistry in 2018.
In 2018, he was honored with the prestigious Norman L. Bowen Award and Lectureship by the American Geophysical Union for his contributions to volcanology, geochemistry, or petrology. In his citation, colleague and mentor Dr. Charles Langmuir wrote of Goldstein:
“For what accomplishments has Steve Goldstein received the Bowen Award? The answers from the community would be diverse. For paleoceanographers, it would be because he pioneered Nd isotopes as an ocean circulation tracer. For those interested in continents, it would be his contributions to understanding continental growth. For mantle geochemists, it would be about the origin of mantle isotope heterogeneity and processes at ridges and convergent margins. Across these communities, the view would be that the honor was overdue, while knowledge of his contributions in other areas would be unlikely to be fully appreciated.”
Goldstein has also earned multiple awards recognizing excellence in his teaching. In 2005, he earned the Columbia University Department of Earth and Environmental Sciences Excellence in Teaching Award, awarded by the Department of Earth and Environmental Sciences Graduate Student Committee for his graduate course, “Isotope Geochemistry”. In 2010, Goldstein received the Columbia University Lenfest Distinguished Faculty Award in honor of his accomplishments in the classroom and as a researcher. In 2022, he was awarded the Columbia University Great Teacher Award by the Society of Columbia Graduates “to recognize and shine a light on great undergraduate teaching at Columbia.”
Personal life
Goldstein was born in East New York (Brooklyn), NY. His father served in WWII and then worked for the FAA and the US Navy. His mother was a homemaker and held part-time jobs. When Goldstein was young, his family moved to Greenbelt, MD and then Bowie, MD, where he graduated from Bowie High School. Goldstein was the first of his immediate family to attend college and earn a PhD. He began his undergraduate degree at University of Maryland, College Park for one year, then moved to McGill University in Montreal, Quebec, finally transferring to Columbia University in his junior year. He graduated with a B.A. in Chemistry and Philosophy, though he knew he would pursue a career in Earth Science. When his PhD advisor moved from Columbia University to University of Cambridge, UK, Goldstein split his time between the two institutions.
During his PhD, Goldstein spent significant time in South America where he traveled, assisted in Peace Corps activities, and collected river sediment samples that would eventually lead to his most highly cited publication. While in Paraguay, Goldstein contracted leishmaniasis from a sand flea bite after his vehicle broke down and he had to spend a night on the side of the road while helping to transport locals for medical care. He was eventually diagnosed and treated with antimony heavy metals at the Hospital for Tropical Disease in London, UK.
Goldstein enjoys music, hiking, biking, and travel. He is conversational in German and Spanish. He is married to Dr. Kerstin Lehnert, Doherty Senior Research Scientist at the Lamont-Doherty Earth Observatory of Columbia University and Director of the Geoinformatics Research Group. Both are huge Bruce Springteen fans.
References
Living people
American geochemists
Columbia College (New York) alumni
Harvard University alumni
Columbia Graduate School of Arts and Sciences alumni
Max Planck Institutes researchers
Columbia University faculty
Fellows of the American Geophysical Union
Year of birth missing (living people)
Lamont–Doherty Earth Observatory people | Steven L. Goldstein | [
"Chemistry"
] | 1,629 | [
"Geochemists",
"American geochemists"
] |
74,945,449 | https://en.wikipedia.org/wiki/TOI-4342 | TOI-4342 is a red dwarf star in the constellation Octans located 201 light-years from Earth. It hosts two transiting exoplanets. Both planets are considered to be good targets for transmission spectroscopy measurements for determination of atmospheric composition.
Stellar characteristics
TOI-4342 is an early red dwarf with an effective temperature of , corresponding to the spectral class M0V. It is a single star with stellar companions ruled out by sky surveys, speckle imaging and the radial velocity method.
Planetary system
The star hosts two planets discovered by the transit method. They were initially observed in TESS data from Sector 13 (June and July 2019) and Sector 27 (July 2020) and were validated with ground based observations with LCO telescope network during 2021, with a study published in 2023. The planets are orbiting close to a 2:1 mean-motion resonance.
Both planets are sub-Neptunes, similar in size, expected to have atmospheres with a significant fraction of hydrogen and helium. Based on the calculated insolation, the planets are expected to have equilibrium temperatures of and respectively.
, the planets' masses have not yet been directly measured, though their masses estimated based on the empirical mass–radius relationship were noted in the discovery paper to fall above the limits of detection for the radial velocity method.
Due to orbiting within of the 2:1 mean-motion resonance, the system is expected to show transit-timing variations due to mutual perturbations. Observation of the amplitudes of this perturbation could additionally help constrain planet masses. However, the limited observations available by the time of the discovery paper were only adequate to rule out deviations by more than from linear ephemerides. The observed low value of perturbation also confirms a low orbital eccentricity for the planets.
See also
TOI-270 – another M-type main sequence star with two sub-Neptunes
References
Octans
M-type main-sequence stars
4342
354944123
J21373286−7758435
Planetary systems with two confirmed planets
Planetary transit variables | TOI-4342 | [
"Astronomy"
] | 425 | [
"Octans",
"Constellations"
] |
74,947,355 | https://en.wikipedia.org/wiki/Corydalis%20Alkaloids | Corydalis Alkaloids are categorized as natural products of the isoquinoline alkaloid type.
Occurrence
Corydalis alkaloids are primarily located within the roots of Corydalis cava and various other Corydalis species.
Representatives
The representatives of Corydalis alkaloids include d-tetrahydrocoptisine (also known as d- or (+)-stylopine), d-canadine, and hydrohydrastinine.
Properties
Corydalis alkaloids exhibit certain narcotic and muscle-paralyzing effects. Historically, the powdered rhizomes of Corydalis alkaloid-containing plants enjoyed popularity as a vermifuge and menstrual stimulant.
References
Alkaloids | Corydalis Alkaloids | [
"Chemistry"
] | 163 | [
"Organic compounds",
"Biomolecules by chemical classification",
"Natural products",
"Alkaloids"
] |
74,947,517 | https://en.wikipedia.org/wiki/Diterpene%20alkaloids | Diterpene alkaloids are natural products of the terpene alkaloid type.
Occurrence
Veatchine is found in the bark of Garrya veatchii, a member of the Cup Catkins family. Aconitine is the main alkaloid in aconite.
Structure
Diterpene alkaloids can be divided into two groups: The diterpene alkaloids, characterized by a C20 parent body, and the norditerpene alkaloids, which are based on a hexacyclic C19 parent body.
Representatives
Diterpene group
Among the C20 alkaloids is the atisine-type (atisine, hetidine, hetisine) and the veatchine-type (Veatchin, Napellin).
Northern iterpene group
The C19 alkaloids include, among others, the aconitine type (aconitine, delphinine) and the lycoctonine type (Lycoctonin, Browniin).
Properties
Aconitine has cardiac arrhythmic and antipyretic properties and is one of the most toxic plant compounds.
References
Alkaloids | Diterpene alkaloids | [
"Chemistry"
] | 252 | [
"Organic compounds",
"Biomolecules by chemical classification",
"Natural products",
"Alkaloids"
] |
74,947,518 | https://en.wikipedia.org/wiki/Dendrobium%20alkaloids | Dendrobium alkaloids are natural products and so-called pseudoalkaloids.
Occurrence
Dendrobium alkaloids are found in the genus Dendrobium, particularly in species like Dendrobium nobile.
Representatives
Approximately 15 alkaloids belong to this group. Notable representatives include Dendrobin, Nobilonin, and Dendroxin.
References
Alkaloids | Dendrobium alkaloids | [
"Chemistry"
] | 83 | [
"Organic compounds",
"Biomolecules by chemical classification",
"Natural products",
"Alkaloids"
] |
74,947,786 | https://en.wikipedia.org/wiki/Rabbit%20vesivirus | Rabbit vesivirus (RaV) is a Caliciviridae virus that was first isolated in the Veterinary Diagnostic Laboratory at Oregon State University, from the feces of rabbits suffering from gastrointestinal disease. The virus is a non-enveloped, isometric virus with diameter of around 30 nanometer.
Its viral genome is 8,295 nucleotides in size, consisting of positive single-stranded RNA with a small protein (VPg) covalently linked to its 5′ terminus and a 3′ poly-A tail with an average length of 85 nucleotides. The genome comprises three open reading frames, the most 5′ of which encodes a 1,880 amino acid proteolysis that yields the non-structural polypeptides upon self-cleavage. The vesivirus is the only genus of which all members are cultivable.
Reference
Caliciviridae
Rabbit diseases | Rabbit vesivirus | [
"Biology"
] | 186 | [
"Virus stubs",
"Viruses"
] |
74,950,931 | https://en.wikipedia.org/wiki/Pi%20Doradus | The Bayer designation Pi Doradus (π Dor / π Doradus) is shared by two stars in the constellation Dorado:
π Doradus, a red giant star.
π Doradus, a red clump giant star.
Doradus, Pi
Dorado | Pi Doradus | [
"Astronomy"
] | 54 | [
"Dorado",
"Constellations"
] |
74,950,936 | https://en.wikipedia.org/wiki/Pi1%20Doradus | {{DISPLAYTITLE:Pi1 Doradus}}
Pi1 Doradus, Latinized from π1 Doradus, is a solitary star located in the southern constellation Dorado near the southwestern border with Mensa. It is faintly visible to the naked eye as an orange-hued point of light with an apparent magnitude of 5.54. Gaia DR3 parallax measurements imply a distance of 660 light-years and it is currently receding with a heliocentric radial velocity of . At its current distance, Pi1 Doradus' brightness is diminished by 0.24 magnitudes due to interstellar extinction and it has an absolute magnitude of −0.83.
Pi1 Doradus has a stellar classification of K5 III, indicating that it is an evolved K-type giant star. It has 1.67 times the mass of the Sun but at the age of 2.67 billion years, it has expanded to 56.5 times the radius of the Sun. It radiates 530 times the luminosity of the Sun from its enlarged photosphere at an effective temperature Gaia DR3 stellar evolution models give a larger radius of and a higher luminosity of . Pi1 Doradus is metal enriched with an iron abundance of [Fe/H] = +0.10 or 126% that of the Sun's. Like many giant stars it spins slowly—having a projected rotational velocity of .
References
K-type giants
Dorado
Doradus, Pi1
Doradus, 38
PD-69 00607
045669
030321
2352
167088607 | Pi1 Doradus | [
"Astronomy"
] | 327 | [
"Dorado",
"Constellations"
] |
74,951,415 | https://en.wikipedia.org/wiki/Warsak%20Canal%20Project | The Warsak Canal Project is an initiative focused on enhancing agricultural practices in the Peshawar and Nowshera districts of Khyber Pakhtunkhwa, Pakistan.
Background
The Warsak Canal Project, also recognized as the Remodeling of Warsak Canal System Project, is projected to augment the water flow in the Warsak canal to a capacity of up to 1250 cusecs. This heightened water flow is expected to significantly enhance farming and agricultural activities in the region.
Impact on agriculture
The initiative aims to provide irrigation to numerous acres of land in Peshawar and Nowshera. This effort will not only convert arid land into fertile grounds but also address water scarcity challenges for local farmers.
Progress and future plans
As of June 2023, the project is in the construction phase, being supervised by Fazl Elahi, the Caretaker Minister for Irrigation. The project encompasses the refurbishment of the Warsak canal and the establishment of a new tunnel. The anticipated completion date for the project is set for February 2027.
The former Chief Minister of Khyber Pakhtunkhwa, Mahmood Khan, has communicated his wish for the updated project plan (referred to as PC-1) to be sanctioned during the forthcoming meeting of the executive committee of the National Economic Council.
References
Infrastructure in Pakistan
Irrigation projects
Agriculture in Pakistan
Khyber Pakhtunkhwa | Warsak Canal Project | [
"Engineering"
] | 269 | [
"Irrigation projects"
] |
74,952,394 | https://en.wikipedia.org/wiki/Pyrrolidine%20alkaloids | The pyrrolidine alkaloids are natural products chemically derived from pyrrolidine.
Occurrence
Alkaloids with partial pyrrolidine structure are usually sub-categorized based on their occurrence and biogenetic origin. Hygrin and cuscohygrin were isolated from the leaves of the coca shrub, while (-)-codonopsinine was isolated from the woodland vine tiger bell.
Representatives
Among the most important representatives of the pyrrolidine alkaloids are hygrin and cuscohygrin. Another representative is the (-)-codonopsinine. Furthermore, ruspolinone, norruspolinone and norruspoline also belong to this alkaloid group.
Properties
Many plants containing cuscohygrin are used in the folk medicine of various peoples as sedatives or narcotics.
References
Alkaloids | Pyrrolidine alkaloids | [
"Chemistry"
] | 183 | [
"Biomolecules by chemical classification",
"Pyrrolidine alkaloids",
"Natural products",
"Organic compounds",
"Alkaloids by chemical classification",
"Alkaloids"
] |
74,954,074 | https://en.wikipedia.org/wiki/AAAI%20Award%20for%20Artificial%20Intelligence%20for%20the%20Benefit%20of%20Humanity | The AAAI Award for Artificial Intelligence for the Benefit of Humanity is an annual prize given by the Association for the Advancement of Artificial Intelligence to recognize the positive impacts of AI to meaningfully improve, protect, and enhance human life. The award is presented annually at the AAAI conference in February. In its first two years, the associated reward was US$1 million, but has since been changed to $25000. Funding is provided by the Chinese online education company Squirrel AI.
The first recipient, in 2021, was Regina Barzilay of MIT for her work developing machine learning models to address drug synthesis and early-stage breast cancer diagnosis.
Recipients
See also
AAAI Awards
List of computer science awards
Association for the Advancement of Artificial Intelligence
Squirrel AI
Turing Award
References
Association for the Advancement of Artificial Intelligence
Awards established in 2021
Computer science awards
International awards | AAAI Award for Artificial Intelligence for the Benefit of Humanity | [
"Technology"
] | 169 | [
"Science and technology awards",
"Computer science",
"Computer science awards",
"International science and technology awards"
] |
74,954,447 | https://en.wikipedia.org/wiki/Heliorapha | Heliorapha is a genus of heliozoan protists, amoeboid eukaryotes with stiff axopodia radiating from their cells. It contains one species, Heliorapha azurina (previously Ciliophrys azurina). It is classified within a monotypic family Helioraphidae inside the actinophryids, a group of heliozoa that belong to the Ochrophyta along with other protists such as diatoms and brown algae.
Morphology
Heliorapha azurina is a heliozoan, a unicellular protist with tapering arms called axopodia sustained by axonemes. Cells of H. azurina have a large, prominent cell nucleus containing a central nucleolus surrounded by peripheral clumps of heterochromatin. The cell body measures 15 μm in diameter, with radiating arms that contain extrusomes. Each cell has a single flagellum that appears at the front of swimming cells or, in non-swimming cells (i.e. during feeding), appears tightly curled, typically in a double "8" shape. Both its large size and the length and shape of its flagellum make it similar to Actinophrys, specifically A. pontica.
Ecology
Heliorapha azurina is a heterotrophic flagellate exclusively found in tropical climates, in both marine and terrestrial habitats. It was isolated from Darwin, Northern Territory, Australia, where it was observed consuming diatoms. It is present in intertidal sediments and surface waters of Darwin. It has also been observed in Ascension Island.
Systematics
Heliorapha azurina is a species previously assigned to the genus Ciliophrys of the Pedinellales, a heliozoan order assigned to Dictyochophyceae, a class of ochrophytes. It was created in 2001 by biologist David J. Patterson to describe cells collected in 1994 from East Point and Lee Point, Darwin, Northern Territory, Australia. In its initial publication, H. azurina (then Ciliophrys azurina) was considered an "evolutionary link" between the Pedinellales and the order Actinophryida, on the basis of presenting traits previously thought as exclusive to each order.
The species differs from Ciliophrys by the presence of tapering axopodia that are too broad at the base to be sustained solely by a triad of microtubules, a characteristic of Pedinellales. This incorrect assignment to the Pedinellales was approached in 2013, when protozoologist Thomas Cavalier-Smith moved the species to its own genus Heliorapha and family Helioraphidae. The family is currently assigned to the Actinophryida, in a suborder known as Actinophryina which unites both Helioraphidae and Actinophryidae.
References
Taxa described in 2013
Ochrophyte genera | Heliorapha | [
"Biology"
] | 621 | [
"Ochrophyta",
"Algae"
] |
74,954,639 | https://en.wikipedia.org/wiki/Cultural%20impact%20of%20TikTok | The online video platform TikTok has had worldwide a social, political, and cultural impact since its global launch in September 2016. The platform has rapidly grown its userbase since its launch and surpassed 2 billion downloads in October, 2020. It became the world's most popular website, ahead of Google, for the year 2021. TikTok's diverse content ecosystem includes popular niches such as music, fitness, beauty, education, and gaming, which cater to a wide range of audiences.
Cultural impact
Music
TikTok has been noted by many media outlets as having a major influence in the music industry. American artist Lil Nas X notably rose to fame after his song "Old Town Road" went viral on TikTok in 2019. He acknowledged the platform's influence in popularizing the song, saying "[TikTok] really boosted the song ... I credit them a lot". Doja Cat has also been noted as an artist who achieved mainstream popularity thanks to her success on TikTok. Insider noted in 2020 that "one of the most popular, pervasive dances of all time" from TikTok was set to Say So, which became her first no.1 hit on the Billboard Hot 100. Pitchfork also noted Doja Cat's "astonishing, unprecedented TikTok reign", saying that before her fame on TikTok, "many people didn’t fully register Doja Cat as a star".
When it was launched, TikTok allowed users to upload videos that ranged from 3 seconds to 1 minute. The short video length limit led to users making sped-up versions of songs to use in their videos. This allowed them to fit more of the song in their video. Some artists, including SZA and Steve Lacy, released official sped-up versions of their songs after unofficial sped-up remixes of their songs went viral on the platform.
TikTok has also helped popularize older songs. Fleetwood Mac's song Dreams re-entered the Billboard Hot 100 over 40 years after its release after a video that featured the song went viral on the platform. Dan Whateley from Insider noted that songs could "rise up organically on the app even if they've been outside the mainstream for decades".
In September 2023, Billboard and TikTok launched a new chart called the TikTok Billboard Top 50 to track music that is popular on the platform in the United States.
Some artists have complained of a "burnout" due to TikTok's massive role in the music marketing process. American singer Halsey said in 2022 that her label was stopping her from releasing a new song if she didn't agree to "fake a viral moment on TikTok".
News and information
TikTok is becoming a growing source of news for Americans. Pew Research Center found that the percentage of US adults who regularly got their news from TikTok more than tripled from 3% of US adults in 2020, to 10% in 2022, and now 14% in 2023. The percentage of US adult TikTok users who regularly get their news from the platform increased from 22% to 33% in the same time period. This is much lower than the percentage of Facebook and Twitter users who regularly get their news from those platforms. However, unlike with TikTok, the proportion of Facebook and Twitter users who get their news from those platforms declined every year from 2020 to 2022.
An increasing proportion of Generation Z internet users have also started using TikTok as their preferred search engine over Google.
Politics
As the popularity of TikTok grows, more and more individuals join the platform. Hence, current political ideologies are being spread on the platform. TikTok has turned into a political landscape, where young individuals are consuming far-right related content on a daily basis. TikTok has allowed for far-right supporters to have a platform where radical views are naturalized. Statistics have shown that roughly 14% of adults regularly get their election and political news through the platform. TikTok has addressed multiple times that hateful content, related to far-right ideologies, is being banned and removed from their platform. However, most hateful content (related to religion, identity, race) have gone unnoticed by the system until December 2019. Although user protection has improved, hateful videos still go undetected by the platform. Additionally, since TikTok functions on an algorithmic system, individuals can get more exposure to hateful content without intending to do so.
Food
TikTok content is able to influence the food choices of its users. A 2023 study of teenagers found that TikTok content influences both short term food decisions, such as trying a new food item or recipe, as well as long term food decisions, like dietary adjustments.
TikTok has also led to an increase in custom orders at restaurants, known on the platform as menu hacks. In 2021, some Starbucks baristas complained of an increase in complicated, custom drinks being ordered that were not on its menu after videos of the customs drinks went viral on TikTok. In 2023, Chipotle Mexican Grill added a viral TikTok custom order created by two influencers as a permanent item to its menu after receiving an influx of orders for the item. The same year, several videos of different Waffle House branches refusing to serve custom orders from TikTok went viral on the platform.
Fashion
The wide audience that TikTok videos are able to reach compared to other platforms allows just a small number of viral videos about a similar style of clothing to create a new microtrend. The high quantity of new microtrends produced by TikTok users has increased the popularity of fast fashion retailers such as Shein, who are able to rapidly reproduce and sell items that are trending on TikTok. Fashion trends and fads that have become popular through social media platforms have collectively become known as "internet aesthetics".
Haul videos are popular amongst TikTok fashion creators. Shein successfully worked with influencers on TikTok and Instagram to grow its business by sending them free clothing and discount codes to share with their followers that earn them a commission on sales. Influencers are also paid to post haul videos for Shein with the free clothing. The popularity of haul videos on TikTok also results in users advertising Shein for free by making and posting their own Shein haul.
Cosmetic surgery
Videos about cosmetic surgery are very popular on TikTok. In January 2022, videos with hashtags related to plastic surgery had over 29 billion views combined on the platform. TikTok and Instagram have led to an increase in the number of cosmetic surgeries performed on young people.
In 2021, Plastic and Reconstructive Surgery published an article that found that plastic surgeons were among the earliest adopters of social media and at the time the article was published, it was found that at least five plastic surgeons had surpassed 1 million followers on TikTok. The article noted that some surgeons were influencers on the platform and had the ability to influence public perception. A 2021 study published by the University of South Florida found that content posted on TikTok by plastic surgeons helped legitimize plastic surgery by educating their viewers and reducing their fear of the surgeries. Plastic surgery is also legitimized by the TikTok recommendation system which shows users who showed interest in plastic surgery videos even more plastic surgery videos via the For You Page, which makes plastic surgery seem more widespread than it actually is among both celebrities and normal people.
TikTok does not allow direct paid advertisements of cosmetic surgeries on its platform, but cosmetic surgery clinics are able to promote their services using normal unpaid posts, as well as by paying influencers or giving them free surgeries in exchange for the influencer posting a video about their cosmetic surgery experience.
Cosmetic procedures that have trended on TikTok include rhinoplasties, buccal fat removals, and botox injections. Cosmetic procedures sometimes trend in the form of an internet challenge on TikTok. The "#Nosejobcheck" challenge involves users posting videos of their noses before and after their rhinoplasties, with a specific background sound for the challenge used in the videos.
Literature
Videos discussing and recommending books has collectively become known as BookTok by users. Books that become popular on BookTok often experience a large increase in sales. The author Colleen Hoover who rose to popularity on BookTok saw six of her books reach the top ten of The New York Times Best Seller list in the paperback trade fiction section in October 2022. An analyst from the book sales tracking service BookScan said that BookTok "remains the industry’s most important platform for discovering new writers". Some publishers have paid popular BookTok influencers to recommend books to capitalise off of the phenomenon.
The success of BookTok content on the platform lead TikTok's parent company, ByteDance, to launch their own publishing company called 8th Note Press in 2023.
Medication shortages
Trends on TikTok have contributed to the shortages of some medications. Danish pharmaceutical company Novo Nordisk produces three medications containing the active ingredient semaglutide. One of the drugs, Wegovy, is certified by the Food and Drug Administration for the treatment of obesity. The other two, Ozempic and Rybelsus, are only certified for the treatment of diabetes. In 2022, the United States suffered shortages of Ozempic after it became a trend on the platform to use the medication off-label for its weight loss effects. Australia's Therapeutic Goods Administration reported that Ozempic's popularity on TikTok had contributed to a global shortage of the medication. It recommended that doctors not prescribe the medication to new patients and prescribe alternative medications to existing patients where possible. By March 2023, TikTok videos posted with the hashtag #Ozempic had amassed 690 million views.
Mental health
TikTok has become a hub for mental health content, where users share personal experiences with depression and anxiety. While this has helped normalize conversations around mental health, it also raises concerns. Dr. Corey Basch, a public health professor, points out that TikTok's algorithm can create echo chambers. Users who engage with posts about anxiety or despair may find themselves bombarded with similar content, which can lead to a harmful cycle.
This surge in mental health discussions has also contributed to more young people self-diagnosing conditions like ADHD and anxiety before consulting a professional. Researchers are concerned about the influence of profit-driven motives, with the platform promoting mental health apps and influencers sponsored by these companies. These services often advertise quick, quiz-based diagnoses, which may oversimplify complex issues. Additionally, misinformation is a growing problem, studies have found that some videos about therapies, like cognitive behavioral therapy, include inaccurate or misleading information
Hustle culture
TikTok has played a huge role in shaping hustle culture, especially during the COVID-19 pandemic, blurring the lines between work and personal life. With over 1 billion daily active users and 60% of U.S. Gen Z checking in regularly, the platform has made productivity a key focus for many users. People share their daily routines, promoting the idea that constant work leads to success. However, this pressure to always be "on" has its downsides. A 2022 study showed 77% of employees felt burned out, which is a consequence of hustle culture.
That said, some creators are pushing back, showing that it's okay to slow down. For example, Jonathan Graziano's "Bones Day" trend encourages followers to take rest when they need it. TikTok gives a wide range of content, from productivity hacks to messages about self-care, offering users the chance to define their own balance.
Other websites
TikTok is now the dominate social media platform amongst the newer generation. The popularity of TikTok has led various other web services to adopt similar features in order to compete with TikTok. Instagram launched added a short, vertical videos section called Instagram Reels to its app in 2020. YouTube followed with the release of YouTube Shorts in 2021. In 2022, Facebook launched a videos tab on its app that shows users a personalized selection of videos. The same year, Twitter announced that it would also be launching a short videos feature and Amazon added a scrolling feed with photos and videos of available products to its mobile app. In 2023, Spotify redesigned its home screen to have a similar scrolling interface to TikTok and Reddit also added a separate video feed to its mobile app.
Economic impact
A 2023 study by Oxford Economics estimated that small and medium-sized enterprises in the United Kingdom who posted on TikTok to advertise their and grow their businesses added £1.6 billion to the UK's gross domestic product in 2022 as a result of their TikTok activity.
Consumer behavior
A 2021 study by Adweek and Morning Consult found that 49 percent of TikTok users bought goods or services after seeing them being discussed or promoted on the platform.
In 2023, the European Journal of Business and Management Research published a study that found that TikTok users were much more likely to trust products shown in TikTok videos that had high quality videos, rather than products shown on the platform that were more useful or had lower prices.
When products go viral on TikTok, the impact on sales can be significant. Stanley tumblers saw their revenue jump from $73 million in 2019 to $750 million last year after going viral on the platform. Feta cheese sales soared by 200% in 2021 after the baked feta pasta recipe took off. CeraVe’s sales increased by over 60% in 2020 as TikTok users turned to the brand during lockdown. Other items, like Cat Crack catnip and Isle of Paradise tanning spray, sold out within days after viral posts.
In 2023, TikTok rolled out a shopping feature called TikTok Shop, making it easy for users to buy products directly from a range of sellers. This feature lets businesses sell products directly on the platform, using tools like shoppable ads, product showcases, and creator partnerships to boost sales and connect with their audience in a more native way. Some fashion and beauty brands have even started thinking about how a product could be featured on TikTok before they finish developing it.
References
Influence of mass media
Cultural impact
Social impact
Internet culture | Cultural impact of TikTok | [
"Technology"
] | 2,969 | [
"Computing and society",
"Social media"
] |
74,955,167 | https://en.wikipedia.org/wiki/Octant%20of%20a%20sphere | In geometry, an octant of a sphere is a spherical triangle with three right angles and three right sides. It is sometimes called a trirectangular (spherical) triangle. It is one face of a spherical octahedron.
For a sphere embedded in three-dimensional Euclidean space, the vectors from the sphere's center to each vertex of an octant are the basis vectors of a Cartesian coordinate system relative to which the sphere is a unit sphere. The spherical octant itself is the intersection of the sphere with one octant of space.
Uniquely among spherical triangles, the octant is its own polar triangle.
The octant can be parametrized using a rational quartic Bézier triangle.
The solid angle subtended by a spherical octant is /2 steradian or one-eight of a spat, the solid angle of a full sphere.
See also
Trirectangular tetrahedron
Notes
Spherical geometry | Octant of a sphere | [
"Mathematics"
] | 193 | [
"Geometry",
"Geometry stubs"
] |
74,955,642 | https://en.wikipedia.org/wiki/Fifth%20Giant | The Fifth Giant is a hypothetical ice giant proposed as part of the Five-planet Nice model, an extension of the Nice model of solar system evolution. This hypothesis suggests that the early Solar System once contained a fifth giant planet in addition to the four currently known giant planets: Jupiter, Saturn, Uranus, and Neptune. The Fifth Giant is theorized to have been ejected from the Solar System due to gravitational interactions during the chaotic phase of planetary migration, approximately 4 billion years ago.
Background
The Nice model, developed in the early 2000s, describes the dynamical evolution of the Solar System following the dissipation of the protoplanetary disk. It posits that the giant planets initially formed in a more compact configuration and subsequently migrated to their current orbits due to interactions with a massive disk of planetesimals. These interactions are believed to have triggered a period of orbital instability, resulting in the dispersal of the planetesimal disk and the capture of irregular moons.
The addition of a fifth giant planet to this model arose as researchers attempted to resolve discrepancies between the Nice Model's predictions and observational data, particularly regarding the current orbital distribution of the outer planets and the Kuiper belt.
Characteristics
The Fifth Giant is hypothesized to have been an ice giant, similar in composition to Uranus and Neptune. It likely had a mass between 10 and 20 Earth masses and an orbit initially located between those of Saturn and Uranus. Computer simulations indicate that such a planet could have influenced the dynamical evolution of the Solar System, shaping the orbits of the outer planets and accounting for the observed gaps in the Kuiper belt.
Ejection mechanism
The ejection of the Fifth Giant is believed to have occurred during the early Solar System's period of instability, when gravitational interactions between the giant planets became chaotic. The planet likely encountered a series of close gravitational encounters with Jupiter or Saturn, resulting in its eventual expulsion from the Solar System. Such an event would have minimized the disruption to the orbits of the remaining planets while aligning with constraints derived from their current orbital architecture.
The ejection process may have also played a role in scattering planetesimals to form the Oort cloud or altering the trajectories of comets and asteroids.
Observational evidence
Direct evidence for the Fifth Giant's existence is lacking, as the planet would have been ejected into interstellar space and is no longer gravitationally bound to the Sun. However, indirect evidence has been cited to support the hypothesis:
Orbital Resonances: The current orbital spacing and resonances among the giant planets are better explained in simulations that include an additional giant planet.
Kuiper Belt Structure: The sculpting of the Kuiper belt and the distribution of trans-Neptunian objects are more consistent with models involving a fifth giant planet.
Irregular Moons: The capture of irregular moons around Jupiter, Saturn, Uranus, and Neptune aligns with the chaotic conditions predicted during the Fifth Giant's ejection.
Related hypotheses
The concept of an additional giant planet is distinct from the search for Planet Nine, a hypothetical planet proposed to explain the clustering of certain trans-Neptunian objects. While both hypotheses suggest the presence of a missing planet, the Fifth Giant would have been ejected billions of years ago, whereas Planet Nine is theorized to remain within the Solar System. However, it is possible that if Planet Nine exists, it could very well be the Fifth Giant as stated by Michael E. Brown during a Twitter inquiry.
See also
Nice model
Five-planet Nice model
Planet Nine
Jumping-Jupiter scenario
Formation and evolution of the Solar System
Kuiper belt
Oort cloud
References
Solar System
Hypothetical planets
Ice giants | Fifth Giant | [
"Astronomy"
] | 758 | [
"Astronomical hypotheses",
"Outer space",
"Astronomical myths",
"Hypothetical astronomical objects",
"Astronomical objects",
"Solar System"
] |
77,919,448 | https://en.wikipedia.org/wiki/ATP-grasp | In molecular biology, the ATP-grasp fold is a unique ATP-binding protein structural motif made of two α+β subdomains that "grasp" a molecule of ATP between them. ATP-grasp proteins have ATP-dependent carboxylate-amine/thiol ligase activity.
Structure
Proteins of the ATP-grasp family have an overall structural configuration organised into three domains referred to as the N-terminal domain (or A-domain), the central domain (or B-domain), and the C-terminal domain (or C-domain).
Function
ATP-grasp enzymes catalyse the ATP-dependent ligation of a carboxylate-containing molecule to an amino or thiol group-containing molecule. The reactions typically involve formation of acylphosphate intermediates. These enzymes are involved in various metabolic pathways including purine biosynthesis, fatty acid synthesis, and gluconeogenesis.
Examples of proteins containing this domain
D-alanine-D-alanine ligase
glutathione synthetase
biotin carboxylase
carbamoyl phosphate synthetase
ribosomal protein S6 modification enzyme (RimK)
urea amidolyase
tubulin-tyrosine ligase
enzymes involved in purine biosynthesis.
Evolution and distribution
The ATP-grasp fold is evolutionarily conserved across different enzyme families and its presence is ubiquitous across prokaryotes and eukaryotes.
Use in research
Researchers have developed several types of inhibitors for these enzymes, including mechanism-based inhibitors, ATP-competitive inhibitors, and non-competitive inhibitors. Some ATP-grasp enzymes are being studied as potential targets for antibiotics and anti-obesity drugs.
References
External links
InterPro: ATP-grasp fold, subdomain 1 (IPR013815)
InterPro: ATP-grasp fold, subdomain 2 (IPR013816)
Protein domains
Protein folds
Protein superfamilies | ATP-grasp | [
"Biology"
] | 399 | [
"Protein superfamilies",
"Protein domains",
"Protein classification"
] |
77,919,873 | https://en.wikipedia.org/wiki/IC%20485 | IC 485 is a spiral galaxy located in the constellation of Gemini, located 375 million light years from Earth. It was discovered by the Austrian astronomer, Rudolf Spitaler on March 6, 1891. It has an estimated diameter of 1.35' x 0.32' arcmin, meaning the galaxy is about 135,000 light years across.
IC 485 is a candidate disc-maser galaxy. It has a projected distance of 122.0 ± 8.5 megaparsecs. The morphology classification of the galaxy is Sa, and it has a low luminous active galactic nucleus (AGN) of LX ~ 5 x 1042 erg s−1. The AGN activity of IC 485 has been debated. It is either classified a LINER or a Seyfert type II galaxy. But its high X-ray luminosity seems to confirm the latter.
Using the Karl G. Jansky Very Large Array observations, a team of astronomers led by Jeremy Darling discovered a H2O maser containing a broad multi-component. The maser of IC 485 has a peak flux of 80 mJy with an isotopic luminosity of Liso = (868 ± 46)LΘ. According to Darling, he was also able to find a faint unresolved radio source with its angular resolution measured as 90 milliarcseconds ≈ 50 parsecs.
In 2022, the galaxy was further studied by another team of astronomers. They discovered, it has two other 22 GHz H2O maser modules with a velocity separation of 472 km s−1. One is located in the central nuclear region while the other is at a redshifted velocity. Based on estimations on its connection with an edge-on disc, IC 485 has a mass of MBH ~ 1.2 x 107 MΘ. According to estimation of its black hole, the galaxy has a core luminosity of 1 x 1036 - 5 x 1037 erg s−1.
References
0485
4156
Spiral galaxies
07572+2650
Astronomical objects discovered in 1891
Active galaxies
Seyfert galaxies
Gemini (constellation) | IC 485 | [
"Astronomy"
] | 439 | [
"Gemini (constellation)",
"Constellations"
] |
77,919,966 | https://en.wikipedia.org/wiki/Next-Generation%20Overhead%20Persistent%20Infrared | Next-Generation Overhead Persistent Infrared (Next-Gen OPIR) is being developed in USA as the replacement for the current missile warning constellation, the Space-Based Infrared System (SBIRS).
The Next-Gen OPIR satellites are engineered to detect and track ballistic missile launches, delivering early warnings of potential attacks. Equipped with advanced infrared sensors, these satellites identify the heat signatures of incoming missiles and securely transmit this vital data to ground stations.
References
External links
Reconnaissance satellites of the United States
Missile defense
Infrared technology
Early warning systems
Military space program of the United States
Military satellites
Equipment of the United States Space Force
Early warning satellites
Military equipment introduced in the 2020s | Next-Generation Overhead Persistent Infrared | [
"Technology"
] | 132 | [
"Warning systems",
"Early warning systems"
] |
77,920,137 | https://en.wikipedia.org/wiki/Bis%282%2C2%2C6%2C6-tetramethyl-4-piperidyl%29%20sebacate | Bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate (abbreviated BTMPS) is a hindered amine light stabilizer used to protect plastics and coatings such as paint from oxidation caused by weathering. like most compounds of this class, it's active form is an aminoxyl radical.
In 2024 it was detected as an adulterant in illicitly sold fentanyl in the United States.
Production and reactions
It is produced by the esterification of sebacic acid and tetramethylpiperidinol (or its oxidised form 4-Hydroxy-TEMPO).
Potential medical significance
It is capable of inhibiting nicotinic acetylcholine receptors. Additionally, it is a potent blocker of L-type calcium channels. It is also able to induce dose-dependent hemodynamic alterations. Similar to early calcium channel blockers, it can precipitate adrenergic release.
References
Plastics additives
Piperidines
Esters
Carboxylate esters
Antioxidants | Bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate | [
"Chemistry"
] | 227 | [
"Organic compounds",
"Esters",
"Functional groups"
] |
77,921,803 | https://en.wikipedia.org/wiki/Hemipholiota%20populnea | Hemipholiota populnea is a mushroom-forming fungus commonly known as destructive Pholiota, although separate from the genus Pholiota. It is saprobic and fruits on the wood of hardwood logs, especially cottonwood.
References
Strophariaceae
Fungus species
Fungi described in 1828
Taxa named by Christiaan Hendrik Persoon | Hemipholiota populnea | [
"Biology"
] | 72 | [
"Fungi",
"Fungus species"
] |
77,921,851 | https://en.wikipedia.org/wiki/Disordered%20local%20moment%20picture | The disordered local moment (DLM) picture is a method, in condensed matter physics, for describing the electronic structure of a magnetic material at a finite temperature, where a probability distribution of sizes and orientations of atomic magnetic moments must be considered. Its was pioneered, among others, by Balázs Győrffy, Julie Staunton, Malcolm Stocks, and co-workers.
The underlying assumption of the DLM picture is similar to the Born-Oppenheimer approximation for the separation of solution of the ionic and electronic problems in a material. In the disordered local moment picture, it is assumed that 'local' magnetic moments which form around atoms are sufficiently long-lived that the electronic problem can be solved for an assumed, fixed distribution of magnetic moments. Many such distributions can then be averaged over, appropriately weighted by their probabilities, and a description of the paramagnetic state obtained. (A paramagnetic state is one where the magnetic order parameter, , is equal to the zero vector.)
The picture is typically based on density functional theory (DFT) calculations of the electronic structure of materials. Most frequently, DLM calculations employ either the Korringa–Kohn–Rostoker (KKR) (sometimes referred to as multiple scattering theory) or linearised muffin-tin orbital (LMTO) formulations of DFT, where the coherent potential approximation (CPA) can be used to average over multiple orientations of magnetic moment. However, the picture has also been applied in the context of supercells containing appropriate distributions of magnetic moment orientations.
Though originally developed as a means by which to describe the electronic structure of a magnetic material above its magnetic critical temperature (Curie temperature), it has since been applied in a number of other contexts. This includes precise calculation of Curie temperatures and magnetic correlation functions for transition metals, rare-earth elements, and transition metal oxides; as well as a description of the temperature dependance of magnetocrystalline anisotropy. The approach has found particular success in describing the temperature-dependence of magnetic quantities of interest in rare earth-transition metal permanent magnets such as SmCo5 and Nd2Fe14B, which are of interest for a range of energy generation and conversion technologies.
References
Condensed matter physics | Disordered local moment picture | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 473 | [
"Phases of matter",
"Condensed matter physics",
"Matter",
"Materials science"
] |
77,922,585 | https://en.wikipedia.org/wiki/UGC%203478 | UGC 3478 is a spiral galaxy, located in the constellation of Camelopardalis. Is is located at 128 million light-years from Earth. It features a growing supermassive black hole (AGN) at its center.
References
Spiral galaxies
Camelopardalis
3478 | UGC 3478 | [
"Astronomy"
] | 61 | [
"Camelopardalis",
"Constellations"
] |
77,924,018 | https://en.wikipedia.org/wiki/Penstemon%20albifluvis | Penstemon albifluvis, the White River penstemon, is a disputed species or variety of Penstemon that grows in a small area in eastern Utah and western Colorado. It grows mainly on broken shale and rock formations in desert habitats. White River penstemon is very rare.
Description
Penstemon albifluvis is a moderate sized herbaceous plant that usually grows between 15 and 45 centimeters tall, but may rarely be as short as 10 cm or as tall as 50 cm. Most often it has 5 to 20 stems that grow straight upwards or grow outwards a short distance before curving to grow upright, but occasionally it may have just one flowering stem. The stems sprout from a branched caudex, a persistent woody structure atop the plant's taproot.
Early in development Penstemon albifluvis will have basal leaves, ones that sprout directly from the caudex, but by the time of flowering they are seldom still present. The leaves on the flowering stems are hairless with edges that are either smooth or curley edges. The lower leaves are oblanceolate, shaped like a reversed spear head with the widest part past the middle of the leaf, and attached by a short stalk to the stem. Further up the leaves are attached directly to the stem and linear, narrower and more grass like, but often somewhat oblanceolate. Leaf size usually ranges from 4–10 cm long and 4–6 millimeters wide, though they may occasionally be as short as 2 cm, as long 12 cm, or as wide as 11 mm.
The inflorescence is a thyrse, a stalk with groups of flowers where the main stem grows indeterminately. There are three to ten groups of flowers on each inflorescence, each group having multiple flowers attached on opposite sides of the stem. Two to four flowers attached to each side. The flowers are tubes with five lobes, each lobe 5–7.3 mm by 2.4–3 mm. The flower as a whole is 22–28 mm long and sparsely covered in glandular hairs on the outside, but may occasionally be as short as 18 mm. The flowers are blue to pale lavender sometimes with light blue lobes. The staminode is 9-10 mm long and entirely contained inside the 14–15 mm long floral tube. It is straight and thinly covered in short orange hairs. The four fertile stamens reach the opening of the tube. They bloom from late may through the month of June.
The seeds are about 2 mm in size and contained within wide egg shaped capsules, 8–11 mm.
Taxonomy
Penstemon albifluvis was scientifically described and named by the botanist John Larry England in 1982. England had encountered the plant while working for the United States Bureau of Land Management. He found the type specimen on the North bank of White River approximately 1.6 kilometers upstream of the Ignatio bridge in Uintah County, Utah. In 1984 Noel Herman Holmgren published a description of the species as a variety of Penstemon scariosus, but as of 2024 it is an accepted species according to Plants of the World Online and World Flora Online. However, many sources including the Flora of North America list it as a subspecies. Though on the other hand, the botanist William Alfred Weber was of the opinion that it is more similar to Penstemon strictus.
Names
The species name, albifluvis, is a botanical Latin compound of albus and fluvis meaning White River for the location of its habitat in western Colorado and eastern Utah. In English it is also commonly called White River penstemon.
Range and habitat
White River penstemon has a natural range of just two counties, Rio Blanco in western Colorado and the neighboring Uintah County in eastern Utah. The only documented Colorado location is on Raven Ridge near the boarder with Utah. It ranges in elevation from 1500–2200 meters. The total size of its range is between 100-250 square kilometers.
It grows with desert shrubs such as sagebrush, shadscale, or rabbitbrush, but also grows in open woodlands characterized by piñon pines, junipers, ponderosa pines, aspens, spruces, or firs. In Colorado it is only found outcrops of Green River Shale, largely barren of life.
Conservation
As a variety it was evaluated by NatureServe in 2022 and listed as critically imperiled (T1) at the global level. It is threatened by grazing and hydrocarbon development.
See also
List of Penstemon species
References
albifluvis
Flora of Colorado
Flora of Utah
Plants described in 1982 | Penstemon albifluvis | [
"Biology"
] | 956 | [
"Biological hypotheses",
"Controversial plant taxa",
"Controversial taxa"
] |
77,925,093 | https://en.wikipedia.org/wiki/Perovskite%20light-emitting%20diode | Perovskite light-emitting diodes (PeLEDs) are candidates for display and lighting technologies. Researchers have shown interest in perovskite light-emitting diodes (PeLEDs) owing to their capacity for emitting light with narrow bandwidth, adjustable spectrum, ability to deliver high color purity, and solution fabrication.
Green PeLEDs
PeLEDs have not surpassed the efficiency of commercial organic light-emitting diodes (OLEDs) because specific critical parameters, such as charge carrier transport and optical output coupling efficiency, have not been optimized.
The development of efficient green PeLEDs with a external quantum efficiency (EQE) exceeding 30% was reported by Bai and his colleagues on May 29, 2023. This achievement was made by adjustments in charge carrier transport and the distribution of near-field light. These optimizations resulted in a light output coupling efficiency of 41.82%.
The modified structure of green PeLED achieved record external quantum efficiency of 30.84% at a brightness level of 6514 cd/m2. This work introduced an approach to building ultra-efficient PeLEDs by balancing electron-hole recombination and enhancing light outcoupling.
Expanding the effective area of perovskite LEDs can decrease their performance. Sun et al. introduced L-methionine (NVAL) to construct an intermediate phase with low formation enthalpy and COO− coordination. This new intermediate phase altered the crystallization pathway, effectively inhibiting phase segregation. Consequently, high-quality large-area quasi-2D perovskite films were achieved. They further fine-tuned the film's composite dynamics, leading to high-efficiency quasi-2D perovskite green LEDs with an effective area of 9.0 cm2. An external quantum efficiency (EQE) of 16.4% was attained at <n> = 3, making it the most efficient large-area perovskite LED. Moreover, a luminance of 9.1×104 cd/m2 was achieved in the <n> = 10 films.
Blue PeLEDs
On March 16, 2023, Zhou et al. published a study demonstrating their successful control of ion behavior to create highly efficient sky-blue perovskite light-emitting diodes. They achieved this by utilizing a bifunctional passivator, which consisted of Lewis base benzoic acid anions and alkali metal cations. This passivator had a dual role: it effectively passivated the deficient lead atom while inhibited the migration of halide ions. The outcome of this innovative approach was the realization of an efficient perovskite LED that emitted light at a stable wavelength of 483 nm. The LED exhibited a commendable external quantum efficiency (EQE) of 16.58%, with a peak EQE reaching 18.65%. Through optical coupling enhancement, the EQE was further boosted to 28.82%.
Red PeLEDs
One of the most crucial aspects of lighting and display technology is the efficient generation of red emission. Quasi-2D perovskites have demonstrated potential for high emission efficiency due to robust carrier confinement. However, the external quantum efficiencies (EQE) of most red quasi-2D PeLEDs are not optimal due to different n-value phases within complex quasi-2D perovskite films.
To address this challenge, Jiang et al. published their findings in Advanced Materials on July 20, 2022. Their research focused on strategically incorporating large cations to enhance the efficiency of red light perovskite LEDs. By introducing phenethylammonium iodide (PEAI)/3-fluorophenylethylammonium iodide (m-F-PEA) and 1-naphthylmethylammonium iodide (NMAI), they achieved precise control over the phase distribution of quasi-2D perovskite materials. This approach effectively reduced the prevalence of smaller n-index phases and concurrently addressed lead and halide defects in the perovskite films. The outcome of this research was the development of perovskite LEDs capable of achieving an EQE of 25.8% at 680 nm, accompanied by a peak brightness of 1300 cd/m2.
White PeLEDs
High-performance white perovskite LED with high light extraction efficiency can be constructed through near-field optical coupling. The near-field optical coupling between blue perovskite diode and red perovskite nanocrystal was achieved by a reasonably designed multi-layer translucent electrode (LiF/Al/Ag/LiF). The red perovskite nano-crystalline layer allows the waveguide mode and surface plasmon polarization mode captured in the blue perovskite diode to be extracted and converted into red light emission, increasing the light extraction efficiency by 50%. At the same time, the complementary emission spectra of blue photons and down-converted red photons contribute to the formation of white LEDs. Finally, the off-device quantum efficiency exceeds 12%, and the brightness exceeds 2000 cd/m2, which are both the highest in white PeLEDs.
Lifetime
Preparing high-quality all-inorganic perovskite films through solution-based methods remains a formidable challenge, primarily attributed to the rapid and uncontrollable crystallization of such materials. The key innovation involved controlling the crystal orientation of the all-inorganic perovskite along the (110) plane through a low-temperature annealing process (35-40 °C). This precise control led to the orderly stacking of crystals, which significantly increased surface coverage and reduced defects within the material. After thorough optimization, the well-oriented CsPbBr3 perovskite LED achieved an external quantum efficiency (EQE) of up to 16.45%, a remarkable brightness of 79,932 cd/m2, and a lifespan of 136 hours when initially operated at a brightness level of 100 cd/m2.
On September 20, 2021, the team led by Sargent et al. from the University of Toronto published their research findings in the Journal of the American Chemical Society (JACS) on bright and stable light-emitting diodes (LEDs) based on perovskite quantum dots within a perovskite matrix. The research reported that perovskite quantum dots remain stable in a precursor solution thin film of perovskite and drive the uniform crystallization of the perovskite matrix using strain quantum dots as nucleation centers. The type I band alignment ensures that quantum dots act as charge acceptors and radiative emitters.
The new material exhibits suppressed biexciton Auger recombination and bright luminescence even at high excitation (600 W/cm2). The red LEDs based on the new material demonstrate an external quantum efficiency of 18% and maintain high performance at a brightness exceeding 4700 cd/m2. The new material extends the LED's operating half-life to 2400 hours at an initial brightness of 100 cd/m2.
References
Solid state engineering | Perovskite light-emitting diode | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 1,472 | [
"Electronic engineering",
"Solid state engineering",
"Condensed matter physics"
] |
77,925,576 | https://en.wikipedia.org/wiki/Baxter%20Street%20School | The Baxter Street School was a public school founded in 1886 in Athens, Georgia, United States. It was initially the first African American public school in the city of Athens; and seven years after opening it was remodeled and became a segregated white school.
History
From 1886 until 1893, it operated as the first segregated public school for African American students in Athens. The same year in 1886, Washington Street School (formerly the Market Street School) in Athens was opened for white students.
The Baxter Street School was a two story brick school building and it had 10-rooms. In 1890, A.J. Carey was made principal; and by 1896, Annie Linton was made principal.
After 1893, the Baxter Street School was remodeled and used exclusively for white students; and the same year, West Broad Street School and East Athens School were opened for African American students. Former principal A.J. Carey moved to the West Broad Street School when it opened.
See also
Knox Institute (1868–1928), private Black school in Athens
References
1886 establishments in Georgia (U.S. state)
Buildings and structures in Athens, Georgia
Educational institutions established in 1886
Historically black schools
Historically segregated African-American schools in Georgia (U.S. state)
Schools in Clarke County, Georgia | Baxter Street School | [
"Engineering"
] | 254 | [
"Architecture stubs",
"Architecture"
] |
77,925,722 | https://en.wikipedia.org/wiki/Fluorothiazinone | Fluorothiazinone (CL-55, Ftortiazinon, Фтортиазинон) is an antibiotic drug, first developed in Russia in 2010 and active against various species of Gram-negative bacteria through inhibition of the type III secretion system (T3SS). It has seen limited clinical use in Russia and is in clinical trials which may eventually see it accepted for use more widely.
See also
List of Russian drugs
Aurodox
Triazavirin
References
Amides
Antibiotics
Catechols
Ethoxy compounds
Experimental drugs
Fluorobenzene derivatives
Russian drugs
Thiadiazines | Fluorothiazinone | [
"Chemistry",
"Biology"
] | 132 | [
"Biotechnology products",
"Biocides",
"Functional groups",
"Antibiotics",
"Amides"
] |
77,925,756 | https://en.wikipedia.org/wiki/Nancy%20Millis%20Medal%20for%20Women%20in%20Science | The Nancy Millis Medal for Women in Science, also known as the Nancy Millis Medal, is an annual award conferred by the Australian Academy of Science. It is named in honour of Nancy Millis (1922–2012) and recognises women scientists, with eight to 15 years's experience after completing their PhD, for their outstanding contribution to research and leadership.
Winners
The medal was first awarded in 2014 and annually since:
2014: Emma Johnston
2015: Tamara Davis
2016: Elena Belousova
2017: Kerrie Ann Wilson
2018: Marie-Liesse Asselin-Labat
2019: Jacqueline Batley
2020: Kate Schroder and Nicole Bell
2021: Angela Moles and Cathryn Trott
2022: Vanessa Peterson
2023: Renae Ryan
2024: Anita Ho-Baillie
References
External links
Australian Academy of Science Awards
Science awards honoring women
Awards established in 2014
Australian science and technology awards | Nancy Millis Medal for Women in Science | [
"Technology"
] | 183 | [
"Science and technology awards",
"Science awards honoring women"
] |
77,925,786 | https://en.wikipedia.org/wiki/IC%20860 | IC 860 is a barred spiral galaxy in the constellation of Coma Berenices. It is located 155 million light years away from Earth. It was discovered on June 16, 1892, by Stephan Javelle, a French astronomer. It is a peculiar galaxy.
IC 860 is classfied a nearby post-starburst galaxy, in early stages of transforming into its quiescent state. It is also vibrationally excited HCN luminous infrared galaxy (LIRG) with LHCN -VIB/LIR of 3.2 x 10−8. It has a dust obscured nucleus making it hard to determine whether it is a starburst galaxy or an active galactic nucleus (AGN). In additional, the galaxy contains HI and OH absorption towards its central region. The galaxy has an implied mass of MSMBH of 4 x 107 MΘ based on its velocity rotation of vrot = 226 km s−1. The Eddington luminosity of IC 860 is 2 x 1012 LΘ.
According to low [C II] 157.7 μm-to-LFIR ratios and by a mid-infrared silicate absorption, the findings suggest IC 860 does have a warm compact region. The region of the galaxy, is in a current phase of rapid evolution where inflows are accumulating column densities of interstellar dust and gas, sufficient to fuel its star formation or its AGN.
IC 860 was also observed in optical imaging. From the results, the galaxy has a massive V-shaped kiloparsec dust structure. As the nuclear gas only has an outflow velocity of vout = 170 – 200 km s−1, this makes it impossible to escape from the galaxy unless being accelerated.
In another study, IC 860 contains 4.83 GHz formaldehyde emission with a peak flux density of 2.0-2.2 mJy based from observations made by Arecibo Observatory. It is found to have three unique emission compartments centered between 3830 and 3990 km s−1.
References
0860
Coma Berenices
046086
IRAS catalogue objects
+04-31-015
Active galaxies
Starburst galaxies
Luminous infrared galaxies
Astronomical objects discovered in 1891
Barred spiral galaxies | IC 860 | [
"Astronomy"
] | 458 | [
"Coma Berenices",
"Constellations"
] |
77,925,920 | https://en.wikipedia.org/wiki/Aurodox | Aurodox (X-5108, goldinomycin) is a naturally occurring polyketide antibiotic drug, first isolated in 1972 from Streptomyces goldiniensis. It is active against various species of Gram-positive bacteria through inhibition of the type III secretion system (T3SS), and while its chemical properties make it unsuitable for use in human medicine directly, it is used in antibiotic research and related compounds may be developed for medical use.
See also
Fluorothiazinone
References
Antibiotics
Dienes
Pyrans
Pyridones
Tetrahydrofurans | Aurodox | [
"Biology"
] | 125 | [
"Antibiotics",
"Biocides",
"Biotechnology products"
] |
77,926,593 | https://en.wikipedia.org/wiki/IC%202531 | IC 2531 is an edge-on spiral galaxy located in the constellation of Antlia. It is located 130 million light years from Earth. It was discovered in February 1898, by the American astronomer Lewis Swift. The galaxy has been called by its nickname "little N 891" because of its resemblance to another edge-on spiral, NGC 891. However IC 2531 is twice as large.
IC 2531 contains a broad HI line. In addition, it has a luminosity class of III and regions of ionized hydrogen.
Characteristics
IC 2531 is classified a late-type galaxy with a projected megaparsec of 36.8. It has an Sb morphological classification. It is seen edge-on and contains a dust lane found separating its main body into two equal components. It has a presence of filamentary features reaching its galactic halo and high circular velocity of vmax = 260.5 km−1. IC 2531 also contains a low far-infrared flux expecting a relatively low contamination of disk light by its young star population.
What is striking about IC 2531, is the fact that its galactic budge has a peculiar box/peanut-shaped structure. Through analyzations of its atomic hydrogen (HI) content as part of the Herschel observations, a total mass of 1.37 x 1010 MΘ was calculated. The galaxy is also shown to have both its HI and stellar disc extending towards the northeast side. It is found having outer regions slightly wrapped along its line of sight and the plane of the sky with both inclination and position angles straying 4 degrees. Furthermore, IC 2531 shows a protruding spiral arm in its disk.
NGC 3054 group
IC 2531 is a member of the NGC 3054 group. There are nine members in the group besides IC 2531 and NGC 3054 including NGC 3051, NGC 3078, NGC 3084, NGC 3089, IC 2537 and two other galaxies from the European Southern Observatory Catalog namely ESO 499-26 and ESO 499–325. IC 2531 is the largest member.
References
02531
Spiral galaxies
028909
-05-24-015
Antlia
Astronomical objects discovered in 1898
Discoveries by Lewis Swift | IC 2531 | [
"Astronomy"
] | 451 | [
"Antlia",
"Constellations"
] |
77,927,443 | https://en.wikipedia.org/wiki/Thomas%20K.%20Gaisser | Thomas Korff Gaisser (March 12, 1940, Evansville, Indiana – February 20, 2022, Swarthmore, Pennsylvania) was a particle physicist, cosmic ray researcher, and a pioneer of astroparticle physics. He is known for his book Cosmic Rays and Particle Physics and the Gaisser–Hillas function.
Biography
Thomas K. Gaisser graduated in 1962 from Wabash College with a B.A. in physics. Supported by a Marshall Scholarship, Gaisser sailed in 1962 to England on RMS Queen Elizabeth. Aboard ship, he met Julia Haig, who also held a Marshall Scholarship. In England the two studied at different universities, but their romance deepened when Gaisser wrote to her asking if she would like to see some plays in London during the academic holidays. They married in 1964 and, over decades, he pursued an academic career in physics, while she pursued an academic career in classics and eventually became a professor of Latin at Bryn Mawr College. In 1965 Thomas Gaisser graduated with an M.Sc. in physics from England's University of Bristol. In 1967 he graduated with a Ph.D. from Brown University. His Ph.D. thesis is entitled Solutions of a Model Field Theoretical Equation for the Neutron-Proton Mass Difference. In 1967 Gaisser and his Ph.D. adviser, Herbert Martin Fried (1929–2023), published a paper related to Gaisser's Ph.D. thesis.
From 1967 to 1969, Gaisser was a research associate at Massachusetts Institute of Technology (MIT) and, for the academic year 1969–1970, a NATO postdoctoral fellow at England's University of Cambridge. In 1970, he became an assistant professor at the Bartol Research Foundation, which in 1970 was located at Swarthmore College. In 1977, the Bartol Research Foundation moved to the University of Delaware and was renamed the Bartol Research Institute. (In 2000, the institute was integrated as a center of the University of Delaware's Department of Physics and Astronomy.) At Bartol, Tom transitioned from particle physics to cosmic ray physics. He stayed at Bartol for the remainder of his career. He was promoted in 1974 from assistant professor to associate professor and in 1979 to full professor. Thomas and Julia Gaisser collaborated in the publication of the 1977 paper Partons in Antiquity. From 1976 to 1978, Gaisser was one of the organizers of the Bartol Conference, held in October 1978, in particle astrophysics, bringing together cosmic ray researchers and particle physicists with expertise involving particle accelerators. In 2001 he became the University of Delaware's Martin A. Pomerantz Professor of Physics. He gained an international reputation for his research in modeling complex phenomena in analytic or semi-analytic formulations involving cosmic-ray physics. He is one of the creators of the Monte Carlo event generator called "Sibyll", which is an important simulator for air showers caused by cosmic rays.
Gasser's research involved calculating the parameters of air showers caused by cosmic rays, computing the antiproton yields of such air showers, and, with Michael Hillas, parameterizing the longitudinal particle density in such air showers. Although primarily a theorist, he traveled to Antarctica for more than 10 seasons, staying for 6 to 7 weeks on each scientific tour. He actively participated in the design and construction of experiments at the Amundsen–Scott South Pole Station. He contributed to the South Pole Air Shower Experiment (SPASE), the Antarctic Muon And Neutrino Detector Array (AMANDA), and, especially, the IceCube Neutrino Observatory with its IceTop surface array measuring air showers. In 1985, Gaisser and his Bartol colleague Todor Stanev calculated the flux of atmospheric neutrinos from Cygnus X-3, a binary star system. Gaisser was the author or co-author of more than 400 scientific articles. He was one of the founding editors of the journal Astroparticle Physics (first published in 1992) and served as a member of the Franklin Institute Committee on Science and the Arts. He is the author of the book Cosmic Rays and Particle Physics (1990); the 2nd edition (2016) was co-authored by Ralph Engel and Elisa Resconi. In 2002, he held a Leverhulme Visiting Professorship at the University of Oxford. In 2003, he and Stuart Pittel were the presenters of the Benjamin Franklin Medal in Physics. From 2007 to 2011 Gaisser was a spokesperson for the IceCube Neutrino Observatory.
Awards and honors
Gaisser was elected a Fellow of the American Astronomical Society and in 1984 a Fellow of the American Physical Society. He received the O’Ceallaigh Medal in 2005 and the Homi Bhabha Medal and Prize in 2015. He was a visiting professor at the Humboldt University of Berlin supported by a Humboldt Research Award in 2009. Gaisser Valley in Antarctica's Cruzen Range is named in his honor.
References
Selected publications
Articles
Books
1940 births
2022 deaths
20th-century American physicists
21st-century American physicists
Wabash College alumni
Alumni of the University of Bristol
Brown University alumni
University of Delaware faculty
Cosmic ray physicists
Particle physicists
Fellows of the American Physical Society
Marshall Scholars
People from Evansville, Indiana
Academic staff of the Humboldt University of Berlin
Recipients of the Homi Bhabha Medal and Prize | Thomas K. Gaisser | [
"Physics"
] | 1,100 | [
"Particle physicists",
"Particle physics"
] |
77,927,706 | https://en.wikipedia.org/wiki/N-Acetyl-3-MMC | N-Acetyl-3-methylmethcathinone is a compound which has been sold as a clanedestine precursor to the designer drug 3-methylmethcathinone (3-MMC). It is primarily produced to avoid local drug laws banning 3-MMC.
In 2019, Dutch police seized a shipment of 350 kilograms of N-acetyl-3-MMC bound for a Dutch clandestine production site. The shipment originated from India. It was found in jerrycans and barrels.
See also
3-Methylmethcathinone
References
Designer drugs
Illegal drug trade
Nervous system drug stubs
Cathinones | N-Acetyl-3-MMC | [
"Chemistry"
] | 132 | [
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
77,927,848 | https://en.wikipedia.org/wiki/CN%20Bo%C3%B6tis | CN Boötis (HD 124953, HR 5343), or simply CN Boo, is a white-hued variable star in the northern constellation of Boötes. With an apparent magnitude of 5.957, it can be faintly seen from Earth by the naked eye, just south-southwest of the much brighter Arcturus. It is located at a distance of according to Gaia EDR3 parallax measurements, and is receding at a radial velocity of . It is a member of the Ursa Major Stream, a group of stars with similar velocities that all formed around 300 million years ago.
It was given its variable star designation, CN Boötis, in 1981. Prior to that it was usually referred to as HR 5343 or HD 124953 in the literature.
Stellar characteristics
CN Boo is a late A-type star with an effective temperature of , and has been classified as either a main-sequence star (spectral type A8V/A9V) or a giant star (spectral type A8III). A 2023 estimate places its radius at a modest 1.6 , which seems to suggest the former.
The star was known to be an Am star since at least 1964, when the Bright Star Catalogue classified it as such. It was first discovered to be a δ Scuti variable in 1979 by Costa et al., with a period of and an amplitude of 0.03 mag. This went against the notion that main-sequence Am stars do not pulsate, something that was accepted as fact at the time, so the team considered the Am classification to be erroneous. A more recent study, however, accepts CN Boo as a pulsating Am star, since it shows a metal abundance pattern archetypal of Am stars, and has a minimum rotation speed (82 km/s) that allows for diffusion processes that cause Am characteristics.
In 1991, CN Boo was found to be a soft X-ray source, meaning that the X-rays it emits are of lower energies, i.e., longer wavelengths. It radiates energy at a rate of 2 ergs per second in X-rays, chiefly at an energy range of below 0.5 keV (wavelength >2.48 nm).
Possible companion
The 1991 edition of the Bright Star Catalogue lists CN Boo as a potential spectroscopic binary. A 2008 study, however, did not detect significant radial velocity variations or any signals of the companion star in the spectrum of CN Boo, meaning that if a secondary star exists, it likely has a flux below 5% that of the primary star.
References
A-type main-sequence stars
Delta Scuti variables
Boötes
124953
BD+19 02779
J14160414+1854426
Stars
5343
Boötis, CN | CN Boötis | [
"Astronomy"
] | 578 | [
"Boötes",
"Constellations"
] |
77,927,892 | https://en.wikipedia.org/wiki/C12H18ClN | {{DISPLAYTITLE:C12H18ClN}}
The molecular formula C12H18ClN may refer to:
Mefenorex
Xylamine | C12H18ClN | [
"Chemistry"
] | 36 | [
"Isomerism",
"Set index articles on molecular formulas"
] |
77,929,507 | https://en.wikipedia.org/wiki/Peak%20power | Peak power refers to the maximum of the instantaneous power waveform, which, for a sine wave, is always twice the average power. For other waveforms, the relationship between peak power and average power is the peak-to-average power ratio (PAPR). It always produces a higher value than the average power figure, however, and so has been tempting to use in advertising without context, making it look as though the amp has twice the power of competitors .
Peak power is a fundamental concept in electrical engineering, relevant to various types of waveforms, including alternating current (AC) and other signal forms. It represents the maximum instantaneous power level that a system can handle or produce. This article explores the significance of peak power across different applications and waveforms.
The peak power of an amplifier is determined by the voltage rails and the maximum amount of current its electronic components can handle for an instant without damage. This characterizes the ability of equipment to handle quickly changing power levels, as many audio signals have a highly dynamic nature.
Radio frequency
Peak power is the highest power level that a transmitter can achieve during its operation. Unlike average power, which is the mean power output over a period, peak power represents the maximum power output at any given instant. This distinction is crucial in applications where signal peaks can significantly exceed the average power level. Peak power is a critical parameter in the field of radio frequency (RF) and telecommunications. It refers to the maximum instantaneous power level that a transmitter can output. Understanding peak power is essential for designing and operating efficient and effective communication systems.
Importance
Peak power is a fundamental concept in the design and operation of transmitters. It plays a crucial role in ensuring signal integrity, system performance, and component reliability. By understanding and managing peak power, engineers can design more efficient and effective communication systems.
Signal Integrity: High peak power ensures that the transmitted signal can overcome noise and interference, maintaining signal integrity over long distances.
System Performance: In systems like radar and communication transmitters, peak power is vital for achieving the desired range and clarity.
Component Stress: Understanding peak power helps in designing components that can withstand these power levels without damage.
Measurement of Peak Power
Measuring peak power involves capturing the highest power level within a specified time frame. This can be done using specialized equipment like peak power meters, which can accurately track and record these peaks. The measurement process must account for various factors, including signal type and modulation.
Applications of Peak Power
Radar Systems: In radar systems, peak power determines the maximum range and resolution. Higher peak power allows for better detection and imaging of distant objects.
Communication Systems: In communication systems, peak power ensures that signals can be transmitted over long distances without significant loss of quality.
Broadcasting: In broadcasting, peak power is crucial for maintaining signal strength and quality, especially in areas with high interference.
Challenges and Considerations
Heat Dissipation: High peak power levels can generate significant heat, requiring efficient cooling systems to prevent damage.
Intermodulation Distortion: Non-linearities in the transmitter can cause intermodulation distortion, affecting signal quality. Proper design and calibration are necessary to minimize these effects.
Regulatory Compliance: Transmitters must comply with regulatory limits on peak power to avoid interference with other communication systems.
References
External links
Definition of peak-to-average ratio – ATIS (Alliance for Telecommunications Industry Solutions) Telecom Glossary 2K
Definition of crest factor – ATIS (Alliance for Telecommunications Industry Solutions) Telecom Glossary 2K
Peak-to-average power ratio (PAPR) of OFDM systems - tutorial
Waveforms
Power (physics) | Peak power | [
"Physics",
"Mathematics"
] | 723 | [
"Physical phenomena",
"Force",
"Physical quantities",
"Quantity",
"Waves",
"Energy (physics)",
"Power (physics)",
"Wikipedia categories named after physical quantities",
"Waveforms"
] |
77,930,248 | https://en.wikipedia.org/wiki/Body%20roundness%20index | Body roundness index (BRI) is a calculated geometric index used to quantify an aspect of a person's individual body shape. Based on the principle of body eccentricity, it provides a rapid visual and anthropometric tool for health evaluation.
Introduced in 2013, the BRI calculation can be used to estimate total and visceral body fat. Ranges of healthy body roundness have been established to accurately classify people with healthy fat mass (weight) compared to obese people who are at risk for morbidities.
Compared to traditional metrics, such as the body mass index (BMI), (which uses weight and height), BRI may improve predictions of the amount of body fat and the volume of visceral adipose tissue. Despite its common use, BMI can misclassify individuals as obese because it does not distinguish between a person's lean body mass and fat mass. Instead, BRI quantifies body girth as well as height, potentially providing more accurate estimates of fat mass.
BRI scores range from 1 to 16, with most people between 1 and 10, although people with scores of 6.9 and up – indicating wider, rounder bodies – were found to have a risk of all-cause mortality that was increased by up to 49% compared to people having a medium BRI of 5. In a 2020 review, high BRI was associated with increased risk of metabolic syndrome and several other diseases.
Typical American adult BRI values range from 3 or less (midsection leanness) to 7 or more (midsection roundness), with a medium index of about 5. As a relatively newer predictive metric, BRI has a smaller research record compared to long-established indices like the BMI and waist-to-hip ratio, so its accuracy and applications remain to be as fully established. Conversely, the simple waist-to-height ratio (which uses the same measurements and is simpler to calculate) has a better research base, leading to its adoption as the preferred guideline in some countries.
History
BRI was first reported in 2013 by the mathematician Diana Thomas and colleagues in an analysis of three databases from studies of demographics, anthropometrics, fat mass, and visceral fat volume. Thomas visualized the human body shape as an egg or ellipse rather than as the cylinder model that is envisioned in the concept of the BMI.
The degree of circularity of an ellipse is quantified by eccentricity, with values between 0 to 1, where 0 is a perfect circle (waist circumference same as height) and 1 is a vertical line. To accommodate human shape data in a greater range, Thomas and colleagues mapped eccentricity in a range of 1 to 20 by using the equation:
Body Roundness Index = 364.2 − 365.5 × Eccentricity
Range of body roundness
Body roundness shapes vary across a range of people who are lean (BRI less than 3) to severely obese (BRI more than 12). According to the authors who developed BRI and subsequent research, overlap between adjacent BRI categories may occur.
Relationship to other anthropometric indices
In using human body and fat mass data from the United States National Health and Nutrition Examination Survey (NHANES) database, the Thomas group found that BRI never was a negative value, and that larger BRI values were associated with people having a round shape, while shape values closer to 1 were related to people with narrow, lean bodies. The maximum observed BRI value in the NHANES data was 16.
BRI had similar accuracy in predicting percentage body fat and percentage fat volume as existing indices, such as the BMI. As the conventional index associated with obesity research, the BMI has numerous drawbacks, as it is unable to distinguish between muscle and fat, is inaccurate in predicting body fat percentage, and has poor ability to predict the risk of heart attack, stroke or death.
In a comparison study with BMI and five other metrics – a body shape index, conicity index, body adiposity index, waist–hip ratio, and abdominal volume index (AVI) – BRI and AVI proved most effective at predicting risk of developing nonalcoholic fatty liver disease (NAFLD). BRI and AVI also accurately stratified diagnosis of NAFLD by race, age, and gender.
Clinical research
The BRI has proved effective as an index for identifying risk of death from different diseases, disorders of metabolic syndrome, liver disease, cardiovascular diseases in association with sarcopenia, and bone mineral density. BRI was also a better indicator than the BMI and body shape index for predicting the risk of hypertension, dyslipidemia, and hyperuricemia in Chinese women.
Limitations
Other indices of body and fat mass, such as BMI and waist-to-height ratio, have undergone more research evaluation and longitudinal clinical applications than BRI, and may be better predictors of fat distribution (e.g., visceral vs. subcutaneous fat) for estimating health risks.
Two measurements of the BRI waist circumference and hip circumference are subject to high variability in standing obese people. Such variability may indicate differences in fat distribution in people with excessive visceral fat, causing errors in BRI.
Diagnostic factors for diseases associated with obesity, such as ethnicity, family history, dietary habits, and physical activity, are not factored into the BRI, or are other outcomes, such as organ health status and duration of disease.
Calculation
The BRI models the human body shape as an ellipse (an oval), with the intent to relate body girth with height to determine body roundness. A simple tape measure suffices to obtain waist circumference and height.
Waist circumference and height can be in any unit of length, as long as they both use the same one.
BRI is calculated as
which can be broken down to 3 steps:
Compute Waist-to-height ratio, = =
Compute eccentricity (e) of the vertical ellipse around the body, sqrt(1-(/)^2)
Compute BRI, 364.3 - 365.5 * ≈
Predictions of % total body fat and % visceral adipose tissue apply a different eccentricity equation using waist and hip circumferences, age, height, gender, ethnicity, and body weight as inputs.
See also
References
Anthropometry
Body shape
Classification of obesity
Human body weight
Human height
Mathematics in medicine
Medical signs
Ratios | Body roundness index | [
"Mathematics"
] | 1,356 | [
"Applied mathematics",
"Mathematics in medicine",
"Ratios",
"Arithmetic"
] |
77,931,605 | https://en.wikipedia.org/wiki/JJC8-089 | JJC8-089 is a dopamine reuptake inhibitor (DRI) that was derived from modafinil and is related to JJC8-016, JJC8-088, and JJC8-091. Its affinity (Ki) for the dopamine transporter (DAT) is 37.8nM, for the norepinephrine transporter (NET) is 11,820nM (313-fold lower than for the DAT), for the serotonin transporter (SERT) is 6,800nM (180-fold lower than for the DAT), and for the sigma σ1 receptor is 2.24nM (17-fold higher than for the DAT). It also has significant affinity for several dopamine receptors. JJC8-089 has substantially higher affinity for the DAT than modafinil. The drug shows pro-motivational effects in animals. It was first described in the scientific literature by 2016.
See also
List of modafinil analogues and derivatives
References
Dopamine reuptake inhibitors
4-Fluorophenyl compounds
Pro-motivational agents
Sigma receptor ligands
Thioethers
Stimulants
Modafinil analogues | JJC8-089 | [
"Chemistry"
] | 262 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
77,931,707 | https://en.wikipedia.org/wiki/Samelisant | Samelisant (; developmental code name SUVN-G3031) is an experimental wakefulness-promoting agent acting as a selective histamine H3 receptor inverse agonist which is under development for the treatment of narcolepsy. It was also under development for the treatment of cognition disorders and Parkinson's disease, but no recent development has been reported for these indications. As of June 2024, samelisant is in phase 2 clinical trials for the treatment of narcolepsy.
See also
Pitolisant
References
Wakefulness-promoting agents
4-Morpholinyl compounds
Anilides
Piperidines
Cyclobutyl compounds | Samelisant | [
"Chemistry"
] | 133 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
77,932,319 | https://en.wikipedia.org/wiki/Lu%20AA47070 | Lu AA47070 is a selective adenosine A2A receptor antagonist that was under development for the treatment of Parkinson's disease but was never marketed. It has been found to reverse some of the effects of dopamine D2 receptor antagonists like pimozide and haloperidol, for instance tremulous jaw movements, catalepsy, locomotor suppression, and other anti-motivational effects, in animals. The drug is a prodrug of Lu AA41063. It was discontinued in phase 1 clinical trials because it lacked the intended pharmacological properties in humans. Lu AA47070 was first described by 2008.
References
Abandoned drugs
Adenosine receptor antagonists
Pro-motivational agents
Prodrugs
Anilides
Fluoroarenes
Benzamides
Thiazolidines
Organophosphates | Lu AA47070 | [
"Chemistry"
] | 177 | [
"Pharmacology",
"Pharmacology stubs",
"Drug safety",
"Medicinal chemistry stubs",
"Prodrugs",
"Chemicals in medicine",
"Abandoned drugs"
] |
77,932,459 | https://en.wikipedia.org/wiki/Kim%20Anh%20Vo | Kim Anh Vo (born 1998 or 1999) is an American hacker who did and assisted operations for the Islamic State Hacking Division throughout 2016 and 2018. She was associated with the sector called Kalachnikv E-Security Team where she also helped recruit others to join the group.
Life
Vo was born on 1998 or 1999 in Georgia, United States where she lived and attended school in Hephzibah, with her high school being 20 minutes south west of Augusta. She loved using computers and showed interest in programming, she would spend most of her time after school using her computer. She also showed interest in working in information technology for the Federal Bureau of Investigation.
Hacking and propaganda
During her time with the computer, she joined the United Cyber Caliphate, also known as the Islamic State Hacking Division in April 2016 and helped assist with operations to release confidential and private information about people, including soldiers of the United States Armed Forces, in data dumps called kill lists. She also spread Islamic State propaganda and memes in support of the Islamic State. She went by the alias' of F@ng, Zozo, Miss. Bones, and Kitty Lee. She recruited a 14-year-old Norwegian boy to join the division in which he then called for attacks against people in New York. She and the boy, making a video, threatened a nonprofit organization that sought to battle what it called extremist ideologies, including the ideologies of the Islamic State. She also spread propaganda telling others to kill people in New York and Brooklyn as well, with a list of 8,700 U.S. citizens' information being released as another "kill list", she made chats in Islamic State chatrooms about the situation and made social media posts stating "We want them #Dead".
Arrest
On March 12, 2019, Vo was arrested in her home after being officially indicted on charges of providing material support to a foreign terrorist organization as a violation of the Patriot Act by a New York federal judge. She was kept as a prisoner in the South District of New York. In April 2020, Vo was granted bail which was set at USD$25,000 and was signed by her mother and a family friend which will let her be released on house arrest in Evans, Georgia with monitoring of her electronics and strict supervision with mental health and therapy sessions via telemedicine with her only being allowed to travel to the south New York and Georgia federal judicial districts and all points in between necessary for travel between the districts.
References
1998 births
1999 births
Hackers
Islamic State of Iraq and the Levant
Islamic State of Iraq and the Levant members from the United States
Islamic State of Iraq and the Levant members
People imprisoned on terrorism charges
Living people
People from Hephzibah, Georgia | Kim Anh Vo | [
"Technology"
] | 555 | [
"Lists of people in STEM fields",
"Hackers"
] |
77,933,098 | https://en.wikipedia.org/wiki/MSX-3 | MSX-3 is a selective adenosine A2A receptor antagonist used in scientific research. Similarly to MSX-4, it is a water-soluble ester prodrug of MSX-2.
Medicinal chemistry
MSX-3, MSX-4, and MSX-2 are xanthines and are derivatives of the non-selective adenosine receptor antagonist caffeine. MSX-2 has been extensively studied due to its high affinity and selectivity for the adenosine A2A receptor, but use of MSX-2 itself has been limited by its poor water solubility.
Whereas MSX-3 is a phosphate ester prodrug of MSX-2 that is suited best for intravenous administration and not for oral administration, MSX-4 is an amino acid ester (L-valine) prodrug of MSX-2 that can be orally administered.
Pharmacology
MSX-2 has 500-fold higher affinity for the adenosine A2A receptor over the adenosine A1 receptor, 580-fold higher affinity for the adenosine A2A receptor over the adenosine A2B receptor, and is inactive at the adenosine A3 receptor.
MSX-3 itself also showed some affinity for the adenosine receptors, but this may have just been due to degradation by phosphatases in the in vitro system.
Animal studies
MSX-3 shows pro-motivational effects in animals. Specifically, although it showed no effect on its own, the drug reverses the effort-related deficits induced by the dopamine depleting agent tetrabenazine (TBZ), the dopamine D2 receptor antagonists haloperidol and eticlopride, and the proinflammatory cytokines interleukin-6 and interleukin-1β.
Conversely, it only mildly attenuates the motivational deficits induced by the dopamine D1 receptor antagonist ecopipam (SCH-39166).
History
MSX-3 was first described in the scientific literature by 1998. A similar agent, MSX-4, was subsequently described by 2008.
References
Adenosine receptor antagonists
Experimental drugs
Phosphate esters
Pro-motivational agents
Prodrugs
Xanthines
Propargyl compounds
3-Methoxyphenyl compounds | MSX-3 | [
"Chemistry"
] | 501 | [
"Chemicals in medicine",
"Xanthines",
"Alkaloids by chemical classification",
"Prodrugs"
] |
77,933,869 | https://en.wikipedia.org/wiki/Icom%20IC-V82 | The Icom IC-V82 is a VHF band handheld transceiver designed by Icom for radio amateurs and professionals who require VHF communication. Although it is a little outdated, (launched in 2004 and discontinued in 2014), the IC-V82 is still valued in the second hand market for a number of additional features such as the ability to convert it, by adding a module, into a digital device, which make it ideal for certain applications requiring voice and/or data encryption.
Features
It is a portable VHF transceiver with coverage in the two-meter band (144–146 MHz) and a maximum output power of 7 watts. It was manufactured and sold by Icom from 2004 to 2014.
frequency : VHF 136-174 MHz
output power : 7 W (high), 4 W (medium), 0.5 W (low)
modulation : FM (Frequency Modulated)
channel memory : 207 channels
screen : LCD with backlight
battery : BP-222N (Ni-Cd) or BP-227 (Li-Ion)
Digital Module
One of the most outstanding features of the IC-V82 is the ability to convert it into a digital device using the additional UT-1181 module sold by Icom Inc.. This module allowed the addition of advanced digital communication and encryption capabilities, including a trunking DMR protocol, digital voice communication and low-speed data in D-STAR format.
History
In June 2022, United Against Nuclear Iran, a U.S. advocacy organization, identified the Icom IC-V82 as being used by Hezbollah, a U.S. designated Foreign Terrorist Organization. It sent a letter to Icom outlining its concerns about the dual-use capability of the transceiver (analog+crypted-digital) and regarding Icom's business ties to Power Group (Icom's representatives in Lebanon) and Faza Gostrar, which claims to be the "Official ICOM representative in Iran".
Many of the devices purchased by Hezbollah that later played a role in the 2024 Lebanon electronic device attacks, killing at least 25 people and wounding over 708, were reported as being IC-V82s. Icom opened an investigation into the case on September 19, 2024, while a sales executive at the company's U.S. subsidiary said the devices involved appeared to be counterfeit units.
Counterfeit models and controversy
After Icom discontinued the IC-V82 in 2014, counterfeit models emerged in China. In addition, another counterfeit model was sold to Hezbollah, and many of the devices used by this group, including pagers like the Gold Apollo AR924, were exploded on September 18, 2024.
Having ceased its production, Icom issued an advisory warning about counterfeit transceivers, including the IC-V82. In October 2018, the company issued a cease-and-desist order against a Chinese manufacturer suspected of producing counterfeit Icom products; it also noted that this was not the first time it had taken such steps.
Protocols
IIDAS
IIDAS is Icom's implementation of the NXDN protocol for two-way digital radio products intended for commercial private land mobile radios (PLMRs) and low-end public safety communications systems. NXDN is a Common Air Interface (CAI) technical standard for mobile communications. It was jointly developed by Icom and Kenwood Corporation.
D-STAR
The "open" D-STAR radio system was developed by Icom based on digital radio protocols developed by the Japan Amateur Radio League and funded by the Ministry of Posts and Telecommunications of Japan. This system is designed to provide advanced voice and data communications over amateur radio using open standards.
Accessories and options
The IC-V82 has a variety of accessories that improve its functionality and ease of use:
Antenna : High gain antenna to improve reception and transmission.
Belt Clip : For comfortable and safe transport.
Optional batteries : Available in different capacities and technologies (Ni-Cd, Li-Ion).
References
External links
World official website (in English)
Old information from Icom Archived (in English)
Complete list of all radio amateur equipment manufactured by Icom
Walkie-talkies
Consumer electronics
Israeli–Lebanese conflict
Mobile telecommunications user equipment
Amateur radio transceivers | Icom IC-V82 | [
"Technology"
] | 868 | [
"Mobile telecommunications",
"Mobile telecommunications user equipment"
] |
77,933,926 | https://en.wikipedia.org/wiki/NGC%203341 | NGC 3341 is a peculiar galaxy located in the constellation of Sextans. It is located 415 million light years away from Earth and has a diameter of 170,000 light years. It was discovered by Albert Marth on March 22, 1865, who described the object as "very faint and small". The galaxy is classified a minor galaxy merger system, with two known companions revealed as offset active galactic nuclei (AGN).
Characteristics
NGC 3341 is classified as a giant disk galaxy located at redshift 0.027. It has a magnitude of MB = -20.3 with a mass of ≈ 1 x 1011 MΘ. The galaxy has two smaller companions of low mass located north from the galaxy with an estimated distance of 5.1 and 8.4 kiloparsecs respectively.
Further observations by astronomers, classified the two offset nuclei of NGC 3341 as dwarf ellipticals or budge remnants of spiral galaxies, whose disk structures were tidal stripped as they coalesced into the larger primary galaxy. According to observations made by Foord and his colleagues, they found the primary nucleus of NGC 3341 has a 0.5-8 keV flux with luminosity of 3.63+0.07-0.05 in harmony with a rest-frame luminosity of 8.54+0.41-0.33 x 1041 erg s−1. The secondary nucleus on the other hand, has an observed 0.5-8 keV flux of 2.7+0.6-0.8 x 10-15 erg s−1 cm−2 s−1. Despite the primary nucleus having an X-ray luminosity of LX > 1 x 1041 erg s−1, the second doesn't.
What is more stranger about the nuclei of NGC 3341, is both of them have different classifications. One is classified a Seyfert type II while the other is a LINER containing weak emission lines. However, the primary nucleus in NGC 3341 contains an emission-line spectrum. Based on the optical spectra of the two nuclei, it is suggested NGC 3341 might well be a dual AGN or a triple AGN system. But because the secondary nucleus never met the X-ray luminosity standards, the merger system of NGC 3341 actually contains a sole AGN.
References
3341
Sextans
Spiral galaxies
Peculiar galaxies
05831
031915
+01-27-031
Astronomical objects discovered in 1865
Discoveries by Albert Marth | NGC 3341 | [
"Astronomy"
] | 510 | [
"Sextans",
"Constellations"
] |
77,933,935 | https://en.wikipedia.org/wiki/Abdulla%20Galadari | Abdulla Galadari is an Emirati scholar of Quranic studies. He is an associate professor at Khalifa University of Science and Technology in Abu Dhabi, United Arab Emirates.
His work focuses on Qur'anic hermeneutics and the engagement of the Quran with Near Eastern traditions in Late Antiquity, employing a multidisciplinary approach that integrates cognitive science of religion and philology.
Biography
Abdulla Galadari completed two B.Sc. degrees from the University of Colorado, followed by an M.Eng. and an M.Sc. from the same institution. He received a Ph.D. in civil engineering at the University of Colorado and later earned a Ph.D. in Arabic and Islamic studies from the University of Aberdeen.
Galadari serves as the convener of the Qur'an and Islamic Tradition in Comparative Perspective section for the Society of Biblical Literature.
Works
Qur'anic Hermeneutics: Between Science, History, and the Bible (2018) (Translated into Turkish by A.Kadir Harmancı)
Metaphors of Death and Resurrection in the Qur’an: An Intertextual Approach with Biblical and Rabbinic Literature (2021) (The book was named a finalist for the 2022 Award for Excellence in the Study of Religion, Textual Studies, by the American Academy of Religion, "in recognition of...exceptional scholarship," as noted by the juries.)
Spiritual Meanings of the Ḥajj Rituals: A Philological Approach (2021)
References
External links
Google scholar page
Living people
Academics of Khalifa University
University of Colorado alumni
Alumni of the University of Aberdeen
Muslim evolutionists
Quranic studies scholars
Theistic evolutionists
History of Quran scholars
21st-century Muslim theologians
Emirati Muslims
Year of birth missing (living people) | Abdulla Galadari | [
"Biology"
] | 360 | [
"Non-Darwinian evolution",
"Theistic evolutionists",
"Biology theories"
] |
67,747,697 | https://en.wikipedia.org/wiki/Pyonitrin | Pyonitrins are a family of unusual alkaloids discovered from an insect-associated Pseudomonas protegens strain. In vivo, pyonitrins A-D show activity against Candida albicans - the causative agent of oral thrush.
Biosynthesis
The pyonitrins are structurally related to both pyochelin and pyrrolnitrin, two well-studied Pseudomonas spp. metabolites. In pyonitrins, the salicylic acid and thiazole rings are identical to those of pyochelin, and the chlorinated aromatic ring is quite similar to that of pyrrolnitrin. These observations indicate that the pathway of pyonitrins biosynthesis is a combination of biosynthetic machineries of these two metabolites. Further studies indicated that the pyochelin and pyrrolnitrin pathways were indeed largely intact.
For pyochelin half-pathway, salicylic acid is first synthesized from chorismate by pchA and pchB enzyme. Then it is activated by the pchD enzyme and is tethered to the pantothenate containing domain of the pchE non-ribosomal peptide synthetase (NRPS). The adenylation domain (A) of pchE activates a molecule of cysteine, which is then attached to the peptidyl carrier protein domain (PCP) of the same protein. In one instance, after condensation, cyclization and dehydration, dihydroaeruginoic acid may be released. The following sequential oxidation and reduction reactions produce aeruginaldehyde, which will be an intermdeiate utilized to obtain pyonitrin. It is worth mentioning that aeruginaldehyde may be further reduced to aeruginol by the pchK reductase. In the normal pathway leading to pyochelin synthesis, a second cysteine molecule is attached by the pchF NRPS and the molecule gets released by the thioesterase domain (TE) of pchF, and converted to the final product pyochelin by the pchK reductase together with nicotinamide adenine dinucleotide phosphate (NADPH) and S-adenosyl methionine (SAM).
For pyrrolnitrin half-pathway, the first step is the chlorination of tryptophan at the 7 position to form 7-chlorotryptophan. Then a rearrangement of the indole ring occurs, forming the phenylpyrrole ring, and followed by decarboxylation to form dechloroaminopyrrolnitrin. This intermediate is then chlorinated a second time to form another key intermediate aminopyrrolnitrin, which undergoes oxidation of the amino group to a nitro group to finally build pyrrolnitrin.
With aeruginaldehyde and dechloroaminopyrrolnitrin (or aminopyrrolnitrin) in hand, they will then undergo a spontaneous Pictet-Spengler condensation. Hence, the additional strategies in pyonitrin biosynthesis likely involves the generation of an imine, followed by an intramolecular electrophilic aromatic addition of the imine carbon onto the pyrrole ring. And the last step would be the rearomatization to yield the isolated pyonitrins A-D. Whether the current coupling is a chance occurrence or a purposeful biosynthetic assembly is not clear, but the pyonitrins derive their chimeric structures from two pathways joining at the metabolomic level.
Total synthesis
Inspired by the proposed biosynthesis pathway, MacMillan group at UC Santa Cruz reported the first biomimetic total synthesis of pyonitrins A−D in three steps in February, 2020.
References
Alkaloids
Thiazoles
Pyrroloquinolines
2-Hydroxyphenyl compounds
Chloroarenes
Halogen-containing alkaloids | Pyonitrin | [
"Chemistry"
] | 863 | [
"Biomolecules by chemical classification",
"Natural products",
"Halogen-containing alkaloids",
"Organic compounds",
"Alkaloids by chemical classification",
"Alkaloids"
] |
67,748,858 | https://en.wikipedia.org/wiki/Topical%20cream%20formulation | Topical cream formulation is an emulsion semisolid dosage form that is used for skin external application. Most of the topical cream formulations contain more than 20 per cent of water and volatiles and/or less than 50 per cent of hydrocarbons, waxes, or polyethylene glycols as the vehicle for external skin application. In a topical cream formulation, ingredients are dissolved or dispersed in either a water-in-oil (W/O) emulsion or an oil-in-water (O/W) emulsion. The topical cream formulation has a higher content of oily substance than gel, but a lower content of oily ingredient than ointment. Therefore, the viscosity of topical cream formulation lies between gel and ointment. The pharmacological effect of the topical cream formulation is confined to the skin surface or within the skin. Topical cream formulation penetrates through the skin by transcellular route, intercellular route, or trans-appendageal route. Topical cream formulation is used for a wide range of diseases and conditions, including atopic dermatitis (eczema), psoriasis, skin infection, acne, and wart. Excipients found in a topical cream formulation include thickeners, emulsifying agents, preservatives, antioxidants, and buffer agents. Steps required to manufacture a topical cream formulation include excipient dissolution, phase mixing, introduction of active substances, and homogenization of the product mixture.
Pharmacology
Human skin can be divided, from outside to inside, into the stratum corneum, viable epidermis, dermis, and underlying hypodermis.
Stratum corneum
The stratum corneum is typically 10–20 μm thick and consists of extracellular lipid-surrounded corneocytes. The lipophilic environment of the stratum corneum can serve as a reservoir for certain highly lipophilic molecules. Keratin found in the stratum corneum may provide great affinity with certain drugs. Both of these interactions can play a role in drug accumulation in the stratum corneum and the local drug action on skin disease.
Viable epidermis
Below the stratum corneum is the viable epidermis. The viable epidermis is usually 50–100 μm thick. It includes immunologically sensitive cells (e.g. Langerhans cells), and metabolically active cells (e.g. keratinocytes, melanocytes, merkel cells). Melanocytes are involved in melanoma pathogenesis. As a result, drugs treating melanoma need to be administered to the lower epidermis.
Dermis
The dermis lies next to the epidermis. It is a 1–2 mm layer mainly composed of fibroblasts and immune cells (e.g. dermal dendritic cells, macrophages, T cells, mast cells) in a collagen and elastic fiber extracellular matrix. These immune cells play important roles in parasitic infections, psoriasis induction, tumor progression, dermal inflammation, angiogenesis, wound healing, tissue remodeling, skin sensitization, and tolerance. Therefore, the regional accumulation of drugs in the dermis is necessary for the prevention and treatment of these local skin diseases.
The hair follicle is an invagination of epidermis cells deep into the dermis. The follicular route is critical in the topical delivery of particle-based formulations and hydrophilic, high-molecular-weight drugs. The follicular route provides benefits such as deeper penetration, prolonged residence duration, faster entry into the skin, and site-specific targeting.
Hypodermis
Beneath these layers lies the hypodermis, which is composed of adipose tissue, fascia, as well as larger lymphatic and blood vessels. For joint and muscle disease treatment, topically applied drugs such as non-steroidal anti-inflammatory drugs (NSAIDs) can penetrate the subcutaneous tissue or even deeper tissues in the hypodermis. Drugs are primarily delivered into the underlying muscle by direct penetration without prior entry into the systemic circulation to prevent unintended side effects.
Routes for topical drug administration
In general, there are three possible routes for drug administration into or across the skin. The first one is the transcellular route, where the drugs are required to pass through both lipid matrix and dead corneocytes of the stratum corneum. The second one is the intercellular route, where the drugs only have to pass through lipid domains between corneocytes. The third one is the trans-appendageal route, where the drugs are transported by hair follicles, sebaceous glands, or sweat glands.
The most common route for drug delivery into the skin is the intercellular route. Multiple steps are involved.
Dissolution and release from the formulation
Partitioning into the stratum corneum
Diffusion through the stratum corneum
Partitioning into the aqueous viable epidermis
Diffusion into the dermis
Excipient
Excipient has a significant impact on the final product performance, manufacturability, and stability. Therefore, the selection of excipients has to be carefully considered during topical cream formulation design.
Oily compounds
In topical cream formulations, oily compounds act as active substance carriers. They also serve as skin penetration enhancers and consistency or viscosity modifiers. The oily excipients may influence cream viscosity, drug solubility, physical stability, drug release performance, and transport into the skin. Oily compounds commonly used in cream formulations include saturated and unsaturated fatty acids/fatty acid esters, hydrocarbons, and polyols.
Thickeners and Emulsifying agents
Topical cream formulations consist of the oily phase and water phase. As the two phases are immiscible, in the absence of thickeners and emulsifying agents, molecules in the topical cream formulation will form droplets. Rapid aggregation of droplets within each phase will eventually lead to phase separation. Physical stability is determined by the mitigation ability to these physical instability phenomena.
Thickeners increase cream viscosity and thus reduce dispersed droplets' mobility. They hinder the separation of phases, thereby increases the physical stability of the cream. For example, the inclusion of methylcellulose and paraffin reduces dispersed droplets' mobility in an oil-in-water emulsion and water-in-oil emulsion respectively.
Emulsifying agents can reduce the interfacial tension between the two phases, thus retards phase separation. Ionic surfactants are used in oil-in-water emulsions, whereas nonionic surfactants are used in both oil-in-water and water-in-oil formulations.
Preservatives and Antioxidants
Oils and fats used in topical cream formulations are susceptible to oxidation by atmospheric oxygen or microorganism action. The stability against oxidation can be enhanced by the introduction of antioxidants. The selection of antioxidants and their concentration can only be determined by testing their effectiveness on the final product, according to pharmacopoeial information. The efficiency of antioxidants depends on their compatibility with other excipients and oil/water partition coefficient.
Oxidations from microbiological source influence the physicochemical properties of the emulsion, resulting in color and odor changes, fat and oil hydrolysis, pH changes in the aqueous phase, or phase separation of the cream. Oil-in-water creams are more susceptible to microbial contamination. Therefore, preservatives are included to prevent any microorganism growth. Preservatives suitable for topical cream formulations must present a broad spectrum of bactericidal activity, low logP, compatibility with other excipients, stability, and effectiveness over a wide range of pH and temperatures.
Buffer agents
By buffering any potential pH change, buffer agents can provide chemical stability and ensure the physical compatibility of the topical cream formulation. They ensure that the formulation can deliver the correct amount of drug to the therapeutic application site, is free from microbial contamination, and physically unchanged since the manufacturing day. Nonetheless, buffer agents need to be carefully added to avoid undesirable effects on physical stability. For example, buffer agents may influence the rheological behavior.
Manufacturing
During the production of the topical cream formulation, the first step is to dissolve excipients in the phase in which they are soluble. The initial mixing temperature of both phases should be high enough to ensure intimate liquid mixing and avoid premature solidification of the oily phase by the colder water. The aqueous phase should be warmed to a temperature slightly higher than the oily phase.
The second step is the mixing of both the aqueous phase and the oily phase by adding either the dispersed phase to the continuous phase, or the continuous phase to the dispersed phase. The effect of the addition order and the addition rate on the drug product quality should be evaluated during process development.
The third step is the introduction of the active substances into the mixture. Some active pharmaceutical ingredients can be dissolved at high temperatures but recrystallize during the cooling stage after mixing. To prevent recrystallization, the active substances can be carried to the cooled down cream base via a powder induction system or through slurry addition. The active substances are simultaneously mixed into the cream base.
The last step is the homogenization stage. Agitators, mechanical mixers, rotor stators, homogenizers, or ultrasonic devices can be employed to ensure uniform excipient dispersion and droplet size reduction. Critical variables of the homogenization equipment include time, temperature, and mechanical energy. Critical parameters must be controlled to produce products of consistent quality.
Medical uses
A wide spectrum of drugs is available as topical cream formulations. Therefore, topical cream formulations are used to treat many skin diseases.
Comparison with gel and ointment
Cream, together with gel and ointment, are semisolid dosage forms intended for topical application. They have different appearances, advantages, disadvantages, and applications.
References
Drug delivery devices
Dosage forms
Ointments | Topical cream formulation | [
"Chemistry"
] | 2,128 | [
"Pharmacology",
"Drug delivery devices"
] |
67,750,523 | https://en.wikipedia.org/wiki/Mine%20Warfare%20Force%20%28Japan%29 | The Mine Warfare Force belonged to the minesweeping force for the self-defense fleet of the Maritime Self-Defense Forces. Its main task is to lay naval mines in the event of an emergency, and it also helps to dispose of mines installed during World War II.
1st Mine Warfare Force
With the surrender of 1945, Japan was demilitarized based on the Potsdam Declaration, and the Imperial Japanese Navy was also dissolved. However, at the end of the war, 55,347 moored minesweepers of the Japanese Navy and 6,546 minesweepers of the Allied Forces remained in the waters near Japan. Based on the instructions of the Commander-in-Chief General Headquarters (GHQ), a minesweeping department was set up by the Military Affairs Bureau of the Ministry of the Navy on September 18, and 6 local minesweeping departments and 17 local minesweeping branches were set up on October 10. Then, the minesweeping force was revived. With the end of the war, the Ministry of the Navy was gradually reduced and dismantled, but under the command of Colonel Kyuzo Tamura, the minesweeping unit changed to the Minesweeping Division of the General Affairs Department of the Demobilization Agency and the Minesweeping Supervision Department, and after the Demobilization Agency closed. It was moved to the Minesweeper Division of the Minesweeper Department of the Ministry of the Navy.
On the other hand, as the deterioration of maritime security due to the disappearance of the Japanese Navy became more serious, in 1948, the Japan Coast Guard was established as a law enforcement agency under the Ministry of Transport, incorporating these minesweeping units derived from the former Navy. On June 1, 1950, the Minesweeping Division was separated from the Guard and Rescue Department, and the Route Enlightenment Headquarters was established in the center and the Route Enlightenment Department was established in the regions as an organization under the direct control of the Secretary. In addition, along with the revision of the organization on June 1, 1951, the whole country was divided into nine coast guard zones, and a route enlightenment department was set up at the coast guard headquarters of each district, and minesweepers were distributed and deployed in each district. Meanwhile, in 1950, the Japanese Special Sweeping Corps was dispatched in response to the Korean War. Although the minesweeping work produced one line of duty, it was highly evaluated by the UN forces during this period when the minesweeping force was extremely weak, and it also led to the improvement of the conditions of the San Francisco Peace Treaty.
When the National Safety Agency Guard was established on August 1, 1952, the route enlightenment work was transferred to this place, and the scavenging boats of the route enlightenment department of each district maritime security headquarters became the Yokosuka District Force. It was incorporated into the Yokosuka District Force, Yokosuka, Hakodate, Seibu, Kure, Osaka, Tokuyama, Shimonoseki, and Sasebo Route Enlightenment Corps (Maizuru District Force, Maizuru, Niigata Route Enlightenment Corps). In order to improve the efficiency of minesweeping work, the 1st to 10th minesweeping forces were formed on November 1 and incorporated into each route enlightenment team, and on September 16, 1953, the route enlightenment team was in charge. As the operations were transferred to the new base corps and base guard, the route enlightenment corps was progressively disbanded. In addition, on October 16, the Second Staff Office and the Route Enlightenment Department of each district were abolished, and a minesweeping section was set up in the security department.
The National Safety Agency Guard was renamed on July 1, 1954, to the Maritime Self-Defense Force. Minesweeping ships JDS Sōei Maru, JDS Yū Chidori and since the 7th Navy Warfare Force and the 1st Mine Warfare Force was formed as a unit under the direct control of the Secretary.
1st Mine Warfare Force
JDS Sōei Maru
JDS Yū Chidori
4th Mine Warfare Group - Kurushima, Iwatsubame, Tomozuru, Hiyodori
7th Mine Warfare Group - Kamoshima, Yoshikiri, Nishikidori
2nd Mine Warfare Force
On January 18, 1955, one Bluebird-class minesweeper was acquired and recommissioned as JDS Yashima, and on March 15, seven Albatross-class (Ujishima-class) vessels were received and the 11th. Formed 12 minesweepers. After receiving three more Bluebird-class vessels, the 21st Minesweeper was formed on January 16, 1956, and two Albatross-class vessels were added, and the 13th Mine Warfare Force was formed on October 1, 1959. Was done. The 1953 from the Atada-class minesweeper of domestic minesweeper deployed also initiated as beginning and 1954 was built from level No. 1-class minesweeper was incorporated into the 101st Mine Warfare Group.
The Kasado-class minesweeper built from 1955 formed the 32nd to 40th Mine Warfare Force in place of the retired and transferred boats, and became the main force of the Mine Warfare Force. As a result of these measures on September 1, 1961, the 2nd Mine Warfare Force was formed.
1st Minesweeper Flotilla
JDS Hayato (Flagship, Kure)
JDS Nasami (Kure)
JDS Suma (Kure)
3rd Mine Warfare Force (Kure) - Hatsutaka, Hayatori, Hiyodori
21st Mine Warfare Force (Sasebo) -Yashima, Tsushima, Hashima
31st Mine Warfare Force (Kure) - Atada, Itsuki, Yashiro
35th Mine Warfare Force (Sasebo) - Shikine, Hirado, Toshima
101st Minesweeper Corps (Kure) - Miho, No.1-class minesweeper
2nd Minesweeper Flotilla
JDS Kiri (Flagship, Yokosuka)
JDS Sōei Maru (Kure)
JDS Tsugaru (Yokosuka)
JDS Erimo (Kure)
32nd Mine Warfare Force (Yokosuka) - Kasado, Shisaka, Kanawa
33rd Mine Warfare Force (Yokosuka) - Sakito, Habushi, Kodzu, Tatara, Tsukumi, Mikura
On this occasion, a plan to set up a minesweeper fleet of the same rank as the escort fleet was also considered, but this did not happen, the first minesweeper group responsible for mine sweeping remained the same, and the newly established second minesweeper group was incorporated into the Self-Defense Fleet and was in charge of general coordination of research and development and education and training for minesweeping. However, during this period, a plan was made to clear the remaining dangerous sea level, and along with the first minesweeper group based in western Japan, the second minesweeper group based in eastern Japan was also put into commercial minesweeping. In March 1969, when the minesweeping area was largely cleared, the 1st Mine Warfare Force was also incorporated into the Self-Defense Fleet.
During this period, underwater disposal teams were being formed in each district unit due to the need for mine hunting , but in 1965, an underwater disposal team consisting of seven members was set up at the Mine Warfare Force Command. The 1976 degrees was built from Hatsushima-class in, remote control of an unmanned underwater vehicle (ROV) mine disposal device S-4 is mounted. With the commissioning of the same type, the 10th Mine Warfare Group below the 11th Mine Warfare Group was revived and assigned to each Mine Warfare Force, the 40th Mine Warfare Group became the local force while the 30th Mine Warfare Group became a support ship.
1st Minesweeper Flotilla
JDS Hayase (Flagship, Kure)
14th Mine Warfare Group (Sasebo) - Yakushima, Narushima, Hikoshima
16th Mine Warfare Group (Kure) - Nuwajima, Etajima
18th Mine Warfare Group (Kure) -Takashima, Himeshima
19th Mine Warfare Group (Kure) - Ogishima, Moroshima, Yurishima
2nd Minesweeper Flotilla
JDS Sōya (Flagship, Yokosuka)
13th Mine Warfare Group (Yokosuka) - Oshima, Niijima
15th Mine Warfare Group (Yokosuka) - Chichijima, Torishima
17th Mine Warfare Group (Yokosuka) - Hahajima, Kamishima
20th Mine Warfare Group (Yokosuka) - Ukishima, Awashima, Sakushima
Mine Warfare Force
1970s than the Soviet Navy had promoted the development of anti-submarine mines, the Maritime Self-Defense Force in the, especially the Bungo Channel, Uraga Channel when installed mines in two choke points, each Kure bases of the 1st underwater disposal team. As the activities of the 2nd Submarine Force at Yokosuka Naval Base were greatly affected, the development of the ability to deal with deep anti-submarine mines became extremely urgent. For this reason, the Uwajima-class, which has the ability to deal with mines in the mid-depth range, and the Yaeyama-class, which has the ability to deal with deep mines, were built in the 61st medium-term defense.
On the other hand, the dispatch of the Self-Defense Forces to Persian Gulf in 1991, was the first overseas dispatch for actual missions after the war, but the Prime Minister received the first special certificate of the Self-Defense Forces, and foreign navies praised the high degree of training. Received high praise from home and abroad. But through this dispatch, from the fact that compared to the United States and Europe that the mechanization and automation of mine sweeping capability has lagged behind large it has been keenly aware of. Uwajima-class based on the design of the Royal Navy of Sandown-class. Construction of the Sugashima-class has introduced a mine sweeping boat system.
The construction cost of a conventional minesweeper was about 5 billion yen, but with the same type, it was 14.6 billion yen, which jumped nearly three times. During this period, the prices of other equipment such as escort vessels and submarines also soared, while the Japanese economy remained in a slump after the period of stable growth, and as a result, the defense budget was required to be restrained. The number of minesweepers was further reduced.
The two minesweeping forces were consolidated into one, and the quantity was reduced, while the headquarters personnel that had been dispersed in the two minesweeping forces were integrated to form the group headquarters. In addition to strengthening the team by establishing a new chief of staff and increasing the number of staff, the quality has improved, such as the establishment of a minesweeping operation support team that manages data on mine tactics and waterway surveys and supports operations against mines. It is planned. In line with this, the name was changed from Minesweeper Flotilla to Mine Warfare Force, and from 2005, the group commander was upgraded to a designated assistant general, and in line with the escort fleet and submarine fleet. , Became one of the four Forces that make up the Self-Defense Fleet.
Mine Warfare Force
JS Uraga
JS Bungo
1st Mine Warfare Group (Kure) - Tobishima, Yugeshima, Nagashima
2nd Mine Warfare Group (Sasebo) - Ogishima, Naoshima, Toyoshima
3rd Mine Warfare Group (Yokosuka) - Sugashima, Notojima, Tsushima
51st Mine Warfare Group (Yokosuka) - Yaeyama, Tsushima, Hachijō
101st Minesweeping Corps (Kure) - Yakushima, Hahajima
Minesweeping Support Team (Yokosuka)
Amphibious Operations
In May 2013, the Ground Self-Defense Force of the Western Army Infantry Regiment with, Maritime Self-Defense Force is the United States Navy, Marine Corps Dawn Blitz 13 exercises (Operation Dawn Blitz) participated in. At this point, any of the Minesweeping Group and the convoy group amphibious warfare not fixed is either responsible for, all of the exercises participation naval vessels escort fleet since it was the affiliation, the 2nd Convoy Group Commander (Major General Hideki Yuasa) became a training controller on the Japanese side.
However, in the 7th Fleet, which is the counterpart on the US side, CTF 76, which was in charge of amphibious operations, has put the anti-thunder warfare unit and the landing operation unit together under the control, so from the aspect of cooperation between Japan and the United States It was more rational for the Japanese side to have a similar system. In addition, in support activities for the 2011 Great East Japan Earthquake, the 4th Maritime Disaster Unit, which is a Minesweeping Group, entered deep into the bay by taking advantage of the characteristics that the draft is shallow and it can turn around quickly and that foreign substances in the water can be detected and avoided by the mine detector. However, it was active in relief activities such as searching and transporting goods.
Since the spring of 2013, the Mine Warfare Force has begun preparations such as demonstrations related to amphibious warfare on the JS Hyūga, and on August 9, the Mine Warfare Force was ready to take charge of amphibious warfare. It was reported that it was done. In September, a dual-purpose war staff member was dispatched to the Mine Warfare Force, and a liaison officer was dispatched from the Ground Self-Defense Force . In 2015, under the command of the Mine Warfare Force, participated in the Dawn Blitz 15 exercise and the US dispatch training, and in San Diego and the sea near it, a series of amphibious operations such as island defense training with the US military and the Ground Self-Defense Force . Conducted command and staff activities related to actions (including support such as supply to the landing force) and amphibious operations.
In March 2016, Major General Yuasa, who was the training controller on the Japanese side in the Dawn Blitz 13 exercise, became the commander of the Mine Warfare Force, and on July 1, the 1st Transport Corps and the 1st Air Cushion Corpss. On this occasion, the ships under the direct control of the group and the 51st Mine Warfare Group were abolished, the 1st Mine Warfare Group was reorganized, and the 3rd Mine Warfare Group was newly formed. As a result of this amphibious operation, the staff organization, which was initially less than 20 people, has been increased to more than 50 people in total.
And in the 30 outlines decided by the Cabinet on December 18, 2018, when the outlines are completed, the number of MSCs and MSOs will be reduced to 12 in total, and to supplement this, the Mogami-class frigate will be given a mine warfare function. It was decided to secure the prescribed function. Six minesweepers and seven frigates are to be organized into two groups.
On October 1, 2020, due to the reorganization of the unit, the minesweeping boats JS Yugeshima and JS Nagashima were decommissioned and the 101st Minesweeping Corps was abolished. The minesweeping business support corps was abolished, and the amphibious and Mine Tactical Support Corps, Amphibious and Mine Warfare Center (AMWC) was newly added. In addition to conventional minesweeping operations, the team will also develop tactics for amphibious warfare and provide education and training to the crew of the new frigates, which has a minesweeping function. In addition, the Mine Warfare Force Command was relocated to the new Maritime Operations Center, a new government building of the Self-Defense Fleet Command completed in the Funakoshi area.
Mine Warfare Force
Mine Warfare Force Headquarters (Yokosuka)
1st Mine Warfare Group (Yokosuka) - Uraga, Awaji, Hirado, Hatsushima
2nd Mine Warfare Group (Sasebo) - Hirashima, Yakushima, Takashima
3rd Mine Warfare Group (Kure) - Bungo, Etajima, Miyajima
Amphibious Warfare / Mine Tactical Support Team (Yokosuka)
Kure Amphibious Warfare / Mine Tactical Support Detachment (Kure)
1st Transport Corps (Kure) - Ōsumi, Shimokita, Kunisaki
1st Air Cushion Boat Corps (Kure)
Citations
External links
Mine Warfare Force
Maritime Self-Defense Force minesweeper Corps group (AttoJMSDF_A_MF_HQ) - Twitter
Both Machines Tactical Corps (AMWC) Official Homepage
Instructions on the organization of the minesweeper
Instructions on the organization of minesweeping operations support team
Units and formations of the Japan Maritime Self-Defense Force
Mine warfare
Naval history of Japan | Mine Warfare Force (Japan) | [
"Engineering"
] | 3,382 | [
"Military engineering",
"Mine warfare"
] |
67,751,287 | https://en.wikipedia.org/wiki/Rosemary%20Kisembo | Rosemary Kisembo, is a Ugandan software engineer and corporate executive, who serves as the Executive Director of the National Identification and Registration Authority of Uganda (NIRA) effective 14 May 2021. She took over from Judy Obitre–Gama, a lawyer, whose contract ended in 2020 and was not extended.
Background and education
She was born in Uganda and she attended local primary and secondary schools. She was then admitted to Makerere University, Uganda's oldest and largest public university, graduating with a Bachelor of Commerce (BCom) degree. Later, she was awarded a Master of Information Systems (MIS) degree, also by Makerere. In addition, she is a Microsoft SQR Server Certified Professional.
Career
Immediately before her present appointment, she was the Head of Information and Communications Technology (ICT) at the Uganda National Roads Authority (UNRA), a role she served in between 2016 and 2021. She served as Manager Software Engineering at UNRA for the period between 2011 and 2016. Before she joined UNRA, she worked at the Uganda Revenue Authority (URA), from 1995 until 2011, serving in the Corporate Services Department of URA.
She was hired at NIRA, following the recommendation of the president of Uganda, that the contract of Judy Obitre-Gama not be renewed. Rosemary Kisembo had to also overcome initial resistance of some technocrats in the Ministry of Internal Affairs and members of the Public Service Commission, who initially viewed her as "unsuitable".
Other considerations
According to Ugandan laws, Rosemary Kisembo, in her capacity as the executive director of NIRA, became a member of the board of directors and is the secretary of that board.
It is expected that under her leadership, NIRA will re-configure the National Registration Card, making it electronically active and adding more features. The new re-designed NIRA card is expected to be issued to the public in 2024.
See also
Uganda Registration Services Bureau
Mercy Kainobwisho
References
External links
Website of the National Identification and Registration Authority of Uganda.
Year of birth missing (living people)
Living people
Tooro people
Software engineers
Makerere University alumni
Ugandan chief executives
People from Western Region, Uganda
Ugandan women chief executives | Rosemary Kisembo | [
"Engineering"
] | 454 | [
"Software engineering",
"Software engineers"
] |
67,751,518 | https://en.wikipedia.org/wiki/4-Bromothiophenol | 4-Bromothiophenol is an organic compound with the formula BrC6H4SH. It forms colorless crystals.
Synthesis
4-Bromothiophenol can be synthesized via the reduction of 4-bromo-benzenesulfonyl chloride by red phosphorus and iodine in an acidic solution. Hydrogenation of 4,4'-dibromodiphenyl disulfide also produces 4-bromothiophenol.
Reactions
It reacts with acetylacetone in the presence of cesium carbonate to give 3-(4-bromophenylthio)pentane-2,4-dione. 4,4'-Dibromophenyl disulfide is also produced as the intermediate.
Like other thiols, it reacts with silver nitrate to produce silver 4-bromothiophenolate.
References
4-Bromophenyl compounds
Thiols | 4-Bromothiophenol | [
"Chemistry"
] | 195 | [
"Organic compounds",
"Thiols"
] |
67,752,109 | https://en.wikipedia.org/wiki/Virgil%20Percec | Virgil Percec (born December 8, 1946) is a Romanian-American chemist and P. Roy Vagelos Chair and Professor of Chemistry at the University of Pennsylvania. Expert in organic, macromolecular and supramolecular chemistry including self-assembly, biological membrane mimics, complex chiral systems, and catalysis. Pioneered the fields of liquid crystals with complex architecture, supramolecular dendrimers, Janus dendrimers and glycodendrimers, organic Frank-Kasper phases and quasicrystals, supramolecular polymers, helical chirality, Ni-catalyzed cross-coupling and multiple living and self-interrupted polymerizations. Most of these concepts were inspired by Nature and biological principles.
Life
Early life
Percec was born in December 1946 in Siret, Romania. His father, Traian, was a schoolteacher and painter; his mother was named Virginia. Virgil attended Eudoxiu Hurmuzachi High School in Rădăuți.
Education
Percec received his BS in Organic and Macromolecular Chemistry at the Polytechnic University in Iași in 1969 and his PhD in 1976 at the Institute of Macromolecular Chemistry in Iași where he had as a mentor. In 1981 he defected from his native country and after short postdoctoral stays at the University of Freiburg in Germany (July 1981 with H.-J. Cantow) and University of Akron, US (August 1981 to March 1982 with J. P. Kennedy) he joined the Department of Macromolecular Science of Case Western Reserve University (CWRU) in Cleveland, US in March 1982 as an Assistant Professor. He was promoted to Associate Professor in 1984 and to Professor in 1986. In 1991 he became director of Materials Research Science and Engineering Centers (MRSEC) and in 1993, he was awarded the Leonard Case Jr. Chair at CWRU. In 1999 he moved to the University of Pennsylvania in Philadelphia as P. Roy Vagelos Chair and Professor of Chemistry. He has been repeatedly a Visiting Professor at the Universities of Freiburg, Ulm and at the Max Planck Institute for Polymer Research in Mainz (all in Germany) and at the Royal Institute of Technology in Stockholm, Sweden.
Personal life
Percec and his wife, Simona, have a daughter Ivona Percec. She earned a double major in Molecular Biology and Medieval History from Princeton University and received an MD and PhD in Genetics from University of Pennsylvania, where she joined the faculty and surgery department.
Research
Percec has made scientific contributions in diverse areas, including the discovery of all helical stereoisomers of polyphenylacetylene, their interconversion and intramolecular electrocyclization with applications in chiral separation, sensors, membranes, molecular machines, the discovery of liquid crystals based on conformational isomerism: polyethers, poly(vinyl ether)s, macrocyclics, covalent and supramolecular dendrimers the discovery of self-assembling dendrons, dendrimers and dendronized polymers; and the creation of helical rod-like and spherical viruses mimics. He generated the first organic Frank-Kasper phases and quasicrystals. He revealed double-helices disregarding chirality and deracemization in crystal state, designed the sequence-rearrangement concept to transform dynamic racemic (atactic) into homochiral (isotactic) supramolecular polymers and demonstrated acceleration of self-assembly and disassembly by fluorine and fluorous phase. His discovery of self-interrupted and self-accelerated iterative organic synthesis, polymerizations and living polymerizations produced the first monodisperse polymers by noniterative synthesis. More recently, he uncovered biological membrane mimics from Janus dendrimers, glycodendrimers and ionizable dendrimers; determined they self-assemble into monodisperse artificial cell-like mimics, co-assemble with bacterial and human cells, and generate one component mRNA delivery systems for virus vaccines and drugs. He is also known for the methodologies he developed for organic, macromolecular and supramolecular synthesis: replacement of Pd with Ni in cross-coupling reactions, the concepts of mixed-ligands and catalytic solvents, phase-transfer catalyzed living condensation polymerization, new mechanisms for living polymerization of acetylenes, single-electron-transfer mediated organic and polymerization reactions including living polymerizations. Percec discovered that the one-component multifunctional sequence-defined amphiphilic Janus dendrimer is an efficient delivery system for mRNA. Designed and synthesized several libraries containing sequence-defined multifunctional ionizable amphiphilic Janus dendrimer (IAJD) by an accelerated modular-orthogonal methodology. Demonstrated they co-assemble with mRNA into dendrimersome nanoparticles (DNPs) by a simple injection method rather than by the complex microfluidic technology. These sequence-defined IAJDs and DNPs are being employed to elucidate the mechanisms of encapsulation and release of mRNA from supramolecular virus-like assemblies and for the production of vaccines and drugs.
Awards and achievements
Percec is the author of more than 800 scientific articles, 20 books and special issues and listed as inventor of at least 80 patents. Percec presented over 1200 endowed, plenary and invited lectures. He has served as the Editor of Journal of Polymer Science: Part A: Polymer Chemistry, Advances in Polymer Science and Book Series “Liquid Crystals”. He serves on Editorial and Advisory Scientific Boards of 24 International Journals, and of the advisory boards of many Academic and Industrial Institutions. Percec organized numerous National and International Symposia including Gordon Conferences, and IUPAC meetings. In 2018, Percec was listed as "Global Highly Cited Researches" by Clarivate Analytics for world-class researches and their exceptional research performance based on multiple highly cited papers that rank in the top 1% by citations for field and year in Web of Sciences. In 2016, 2015, and 2014 he was listed as "One of The World's Most Influential Scientific Minds of our Time" by Thomson Reuters. Percec delivered over 1400 plenary endowed lectures including: the Raychem Lecturer, Chemistry Department, University of California, Berkeley, CA (1996); The 4th Aggarwal Lecturer in Polymer Science, Chemistry Department, Cornell University, NY (1997); The Inaugural Woodward Lecturer "Frontiers in Chemical Sciences", Harvard University (2004); the 7th Rohm and Haas Lecture at the University of California, Berkeley (2005); the Lecturer of the Swiss Chemical Society (2008); Invited Lecture at Kekule Institute of Organic Chemistry and Biochemistry at the University of Bonn (2010); the Inaugural Kavli Foundation Innovations in Chemistry Lecture and Award, American Chemical Society (2011); The 8th International Dendrimer Symposium (2013); the Inaugural Aldrich lecture at Massachusetts Institute of Technology (2015); Ben-Gurion University of the Negev, Israel, Department of Chemistry and the Faculty of Natural Science's Distinguished Scientist Visitor and Lecturers (2016); IVA 100: Centennial Jubilee Workshop of the Royal Swedish Academy of Engineering Sciences (2019). Percec is an Honorary Foreign Member of the Romanian Academy (1993), Doctor Honoris Causa of University of Athens (Greece), Polytechnic University Iasi (Romania) since 2007 and of Polytechnic University, Bucharest (2016). He is an Honorary Member of the Israel Chemical Society (2009) and of the Romanian Society of Chemistry and "Petru Poni" Medal of the Romanian Society of Chemistry (2014). Percec educated over 300 PhD and postdoctoral students with more than 70 of them being in faculty positions.
Awards
2020 Elected Foreign Member of Academia Europaea.
2016, 2000, 1995, 1990, National Science Foundation Research Award for Creativity in Research.
2015, "Cristofor Simionescu" Award for Excellence in Macromolecular Chemistry- The Inaugural American Chemical Society in Collaboration with the Romanian International Chapter.
2013, The Joseph and Josephine Rabinowitz Award for Excellence in Research at The University of Pennsylvania School of Dental Medicine.
2013, Honorary Foreign Member of the Royal Swedish Academy of Engineering Sciences IVA.
2012 and 1997, Humboldt Research Award for Senior US Scientists Alexander von Humboldt Foundation
2008, The Herman F. Mark Medal and The Polymer Award from the Austrian Research Institute for Chemistry and Technology, Vienna, Austria.
2008, The International Award and Silver Medal of the Society of Polymer Science, Japan.
2007, International Award of The Society of Polymer Science, Japan (SPSJ).
2005, Staudinger-Durrer Medal, ETH, Zurich, Switzerland.
2004, American Chemical Society Award in Polymer Chemistry.
2002, Polymer Technology Netherland (PTN) Award from the Netherlands.
References
1946 births
Living people
People from Siret
Romanian chemists
Eudoxiu Hurmuzachi National College alumni
Gheorghe Asachi Technical University of Iași alumni
Romanian emigrants to the United States
Case Western Reserve University faculty
University of Pennsylvania faculty
American organic chemists
20th-century American chemists
21st-century American chemists | Virgil Percec | [
"Chemistry"
] | 1,920 | [
"Organic chemists",
"American organic chemists"
] |
67,752,523 | https://en.wikipedia.org/wiki/Jury%20theorem | A jury theorem is a mathematical theorem proving that, under certain assumptions, a decision attained using majority voting in a large group is more likely to be correct than a decision attained by a single expert. It serves as a formal argument for the idea of wisdom of the crowd, for decision of questions of fact by jury trial, and for democracy in general.
The first and most famous jury theorem is Condorcet's jury theorem. It assumes that all voters have independent probabilities to vote for the correct alternative, these probabilities are larger than 1/2, and are the same for all voters. Under these assumptions, the probability that the majority decision is correct is strictly larger when the group is larger; and when the group size tends to infinity, the probability that the majority decision is correct tends to 1.
There are many other jury theorems, relaxing some or all of these assumptions.
Setting
The premise of all jury theorems is that there is an objective truth, which is unknown to the voters. Most theorems focus on binary issues (issues with two possible states), for example, whether a certain defendant is guilty or innocent, whether a certain stock is going to rise or fall, etc. There are voters (or jurors), and their goal is to reveal the truth. Each voter has an opinion about which of the two options is correct. The opinion of each voter is either correct (i.e., equals the true state), or wrong (i.e., differs than the true state). This is in contrast to other settings of voting, in which the opinion of each voter represents his/her subjective preferences and is thus always "correct" for this specific voter. The opinion of a voter can be considered a random variable: for each voter, there is a positive probability that his opinion equals the true state.
The group decision is determined by the majority rule. For example, if a majority of voters says "guilty" then the decision is "guilty", while if a majority says "innocent" then the decision is "innocent". To avoid ties, it is often assumed that the number of voters is odd. Alternatively, if is even, then ties are broken by tossing a fair coin.
Jury theorems are interested in the probability of correctness - the probability that the majority decision coincides with the objective truth. Typical jury theorems make two kinds of claims on this probability:
Growing Reliability: the probability of correctness is larger when the group is larger.
Crowd Infallibility: the probability of correctness goes to 1 when the group size goes to infinity.
Claim 1 is often called the non-asymptotic part and claim 2 is often called the asymptotic part of the jury theorem.
Obviously, these claims are not always true, but they are true under certain assumptions on the voters. Different jury theorems make different assumptions.
Independence, competence, and uniformity
Condorcet's jury theorem makes the following three assumptions:
Unconditional Independence: the voters make up their minds independently. In other words, their opinions are independent random variables.
Unconditional Competence: the probability that the opinion of a single voter coincides with the objective truth is larger than 1/2 (i.e., the voter is smarter than a random coin-toss).
Uniformity: all voters have the same probability of being correct.
The jury theorem of Condorcet says that these three assumptions imply Growing Reliability and Crowd Infallibility.
Correlated votes: weakening the independence assumption
The opinions of different voters are often correlated, so Unconditional Independence may not hold. In this case, the Growing Reliability claim might fail.
Example
Let be the probability of a juror voting for the correct alternative and be the (second-order) correlation coefficient between any two correct votes. If all higher-order correlation coefficients in the Bahadur representation of the joint probability distribution of votes equal to zero, and is an admissible pair, then the probability of the jury collectively reaching the correct decision under simple majority is given by:
where is the regularized incomplete beta function.
Example: Take a jury of three jurors , with individual competence and second-order correlation . Then . The competence of the jury is lower than the competence of a single juror, which equals to . Moreover, enlarging the jury by two jurors decreases the jury competence even further, . Note that and is an admissible pair of parameters. For and , the maximum admissible second-order correlation coefficient equals .
The above example shows that when the individual competence is low but the correlation is high:
The collective competence under simple majority may fall below that of a single juror;
Enlarging the jury may decrease its collective competence.
The above result is due to Kaniovski and Zaigraev. They also discuss optimal jury design for homogenous juries with correlated votes.
There are several jury theorems that weaken the Independence assumption in various ways.
Truth-sensitive independence and competence
In binary decision problems, there is often one option that is easier to detect that the other one. For example, it may be easier to detect that a defendant is guilty (as there is clear evidence for guilt) than to detect that he is innocent. In this case, the probability that the opinion of a single voter is correct is represented by two different numbers: probability given that option #1 is correct, and probability given that option #2 is correct. This also implies that opinions of different voters are correlated. This motivates the following relaxations of the above assumptions:
Conditional Independence: for each of the two options, the voters' opinions given that this option is the true one are independent random variables.
Conditional Competence: for each of the two options, the probability that a single voter's opinion is correct given that this option is true is larger than 1/2.
Conditional Uniformity: for each of the two options, all voters have the same probability of being correct given that this option is true.
Growing Reliability and Crowd Infallibility continue to hold under these weaker assumptions.
One criticism of Conditional Competence is that it depends on the way the decision question is formulated. For example, instead of asking whether the defendant is guilty or innocent, one can ask whether the defendant is guilty of exactly 10 charges (option A), or guilty of another number of charges (0..9 or more than 11). This changes the conditions, and hence, the conditional probability. Moreover, if the state is very specific, then the probability of voting correctly might be below 1/2, so Conditional Competence might not hold.
Effect of an opinion leader
Another cause of correlation between voters is the existence of an opinion leader. Suppose each voter makes an independent decision, but then each voter, with some fixed probability, changes his opinion to match that of the opinion leader. Jury theorems by Boland and Boland, Proschan and Tong shows that, if (and only if) the probability of following the opinion leader is less than 1-1/2p (where p is the competence level of all voters), then Crowd Infallibility holds.
Problem-sensitive independence and competence
In addition to the dependence on the true option, there are many other reasons for which voters' opinions may be correlated. For example:
Deliberation among voters;
Peer pressure;
False evidence (e.g. a guilty defendant that excels at pretending to be innocent);
External conditions (e.g. poor weather affecting their judgement).
Any other common cause of votes
It is possible to weaken the Conditional Independence assumption, and conditionalize on all common causes of the votes (rather than just the state). In other words, the votes are now independent conditioned on the specific decision problem. However, in a specific problem, the Conditional Competence assumption may not be valid. For example, in a specific problem with false evidence, it is likely that most voters will have a wrong opinion. Thus, the two assumptions - conditional independence and conditional competence - are not justifiable simultaneously (under the same conditionalization).
A possible solution is to weaken Conditional Competence as follows. For each voter and each problem x, there is a probability p(x) that the voter's opinion is correct in this specific problem. Since x is a random variable, p(x) is a random variable too. Conditional Competence requires that p(x) > 1/2 with probability 1. The weakened assumption is:
Tendency to Competence: for each voter, and for each r>0, the probability that p(x) = 1/2+r is at least as large as the probability that p(x) = 1/2-r.
A jury theorem by Dietrich and Spiekerman says that Conditional Independence, Tendency to Competence, and Conditional Uniformity, together imply Growing Reliability. Note that Crowd Infallibility is not implied. In fact, the probability of correctness tends to a value which is below 1, if and only of Conditional Competence does not hold.
Bounded correlation
A jury theorem by Pivato shows that, if the average covariance between voters becomes small as the population becomes large, then Crowd Infallibility holds (for some voting rule). There are other jury theorems that take into account the degree to which votes may be correlated.
Other solutions
Other ways to cope with voter correlation include causal networks, dependence structures, and interchangeability.
Diverse capabilities: weakening the uniformity assumption
Different voters often have different competence levels, so the Uniformity assumption does not hold. In this case, both Growing Reliability and Crowd Infallibility may not hold. This may happen if new voters have much lower competence than existing voters, so that adding new voters decreases the group's probability of correctness. In some cases, the probability of correctness might converge to 1/2 (- a random decision) rather than to 1.
Stronger competence requirements
Uniformity can be dismissed if the Competence assumption is strengthened. There are several ways to strengthen it:
Strong Competence: for each voter i, the probability of correctness pi is at least 1/2+e, where e>0 is fixed for all voters. In other words: the competence is bounded away from a fair coin toss. A jury theorem by Paroush shows that Strong Competence and Conditional Independence together imply Crowd Infallibility (but not Growing Reliability).
Average Competence: the average of the individual competence levels of the voters (i.e. the average of their individual probabilities of deciding correctly) is slightly greater than half, or converges to a value above 1/2. Jury theorems by Grofman, Owen and Feld, and Berend and Paroush, show that Average Competence and Conditional Independence together imply Crowd Infallibility (but not Growing Reliability).
Random voter selection
instead of assuming that the voter identity is fixed, one can assume that there is a large pool of potential voters with different competence levels, and the actual voters are selected at random from this pool (as in sortition).
A jury theorem by Ben Yashar and Paroush shows that, under certain conditions, the correctness probability of a jury, or of a subset of it chosen at random, is larger than the correctness probability of a single juror selected at random. A more general jury theorem by Berend and Sapir proves that Growing Reliability holds in this setting: the correctness probability of a random committee increases with the committee size. The theorem holds, under certain conditions, even with correlated votes.
A jury theorem by Owen, Grofman and Feld analyzes a setting where the competence level is random. They show what distribution of individual competence maximizes or minimizes the probability of correctness.
Weighted majority rule
When the competence levels of the voters are known, the simple majority rule may not be the best decision rule. There are various works on identifying the optimal decision rule - the rule maximizing the group correctness probability. Nitzan and Paroush show that, under Unconditional Independence, the optimal decision rule is a weighted majority rule, where the weight of each voter with correctness probability pi is log(pi/(1-pi)), and an alternative is selected if the sum of weights of its supporters is above some threshold. Grofman and Shapley analyze the effect of interdependencies between voters on the optimal decision rule. Ben-Yashar and Nitzan prove a more general result.
Dietrich generalizes this result to a setting that does not require prior probabilities of the 'correctness' of the two alternative. The only required assumption is Epistemic Monotonicity, which says that, if under certain profile alternative x is selected, and the profile changes such that x becomes more probable, then x is still selected. Dietrich shows that Epistemic Monotonicity implies that the optimal decision rule is weighted majority with a threshold. In the same paper, he generalizes the optimal decision rule to a setting that does not require the input to be a vote for one of the alternatives. It can be, for example, a subjective degree of belief. Moreover, competence parameters do not need to be known. For example, if the inputs are subjective beliefs x1,...,xn, then the optimal decision rule sums log(xi/(1-xi)) and checks whether the sum is above some threshold. Epistemic Monotonicity is not sufficient for computing the threshold itself; the threshold can be computed by assuming expected-utility maximization and prior probabilities.
A general problem with the weighted majority rules is that they require to know the competence levels of the different voters, which is usually hard to compute in an objective way. Baharad, Goldberger, Koppel and Nitzan present an algorithm that solves this problem using statistical machine learning. It requires as input only a list of past votes; it does not need to know whether these votes were correct or not. If the list is sufficiently large, then its probability of correctness converges to 1 even if the individual voters' competence levels are close to 1/2.
More than two options
Often, decision problems involve three or more options. This critical limitation was in fact recognized by Condorcet (see Condorcet's paradox), and in general it is very difficult to reconcile individual decisions between three or more outcomes (see Arrow's theorem).
This limitation may also be overcome by means of a sequence of votes on pairs of alternatives, as is commonly realized via the legislative amendment process. (However, as per Arrow's theorem, this creates a "path dependence" on the exact sequence of pairs of alternatives; e.g., which amendment is proposed first can make a difference in what amendment is ultimately passed, or if the law—with or without amendments—is passed at all.)
With three or more options, Conditional Competence can be generalized as follows:
Multioption Conditional Competence: for any two options x and y, if x is correct and y is not, then any voter is more likely to vote for x than for y.
A jury theorem by List and Goodin shows that Multioption Conditional Competence and Conditional Independence together imply Crowd Infallibility. Dietrich and Spiekermann conjecture that they imply Growing Reliability too. Another related jury theorem is by Everaere, Konieczny and Marquis.
When there are more than two options, there are various voting rules that can be used instead of simple majority. The statistic and utilitarian properties of such rules are analyzed e.g. by Pivato.
Indirect majority systems
Condorcet's theorem considers a direct majority system, in which all votes are counted directly towards the final outcome. Many countries use an indirect majority system, in which the voters are divided into groups. The voters in each group decide on an outcome by an internal majority vote; then, the groups decide on the final outcome by a majority vote among them. For example, suppose there are 15 voters. In a direct majority system, a decision is accepted whenever at least 8 votes support it. Suppose now that the voters are grouped into 3 groups of size 5 each. A decision is accepted whenever at least 2 groups support it, and in each group, a decision is accepted whenever at least 3 voters support it. Therefore, a decision may be accepted even if only 6 voters support it.
Boland, Proschan and Tong prove that, when the voters are independent and p>1/2, a direct majority system - as in Condorcet's theorem - always has a higher chance of accepting the correct decision than any indirect majority system.
Berg and Paroush consider multi-tier voting hierarchies, which may have several levels with different decision-making rules in each level. They study the optimal voting structure, and compares the competence against the benefit of time-saving and other expenses.
Goodin and Spiekermann compute the amount by which a small group of experts should be better than the average voters, in order for them to accept better decisions.
Strategic voting
It is well-known that, when there are three or more alternatives, and voters have different preferences, they may engage in strategic voting, for example, vote for the second-best option in order to prevent the worst option from being elected. Surprisingly, strategic voting might occur even with two alternatives and when all voters have the same preference, which is to reveal the truth. For example, suppose the question is whether a defendant is guilty or innocent, and suppose a certain juror thinks the true answer is "guilty". However, he also knows that his vote is effective only if the other votes are tied. But, if other votes are tied, it means that the probability that the defendant is guilty is close to 1/2. Taking this into account, our juror might decide that this probability is not sufficient for deciding "guilty", and thus will vote "innocent". But if all other voters do the same, the wrong answer is derived. In game-theoretic terms, truthful voting might not be a Nash equilibrium. This problem has been termed the swing voter's curse, as it is analogous to the winner's curse in auction theory.
A jury theorem by Peleg and Zamir shows sufficient and necessary conditions for the existence of a Bayesian-Nash equilibrium that satisfies Condorcet's jury theorem. Bozbay, Dietrich and Peters show voting rules that lead to efficient aggregation of the voters' private information even with strategic voting.
In practice, this problem may not be very severe, since most voters care not only about the final outcome, but also about voting correctly by their conscience. Moreover, most voters are not sophisticated enough to vote strategically.
Subjective opinions
The notion of "correctness" may not be meaningful when making policy decisions, which are based on values or preferences, rather than just on facts.
Some defenders of the theorem hold that it is applicable when voting is aimed at determining which policy best promotes the public good, rather than at merely expressing individual preferences. On this reading, what the theorem says is that although each member of the electorate may only have a vague perception of which of two policies is better, majority voting has an amplifying effect. The "group competence level", as represented by the probability that the majority chooses the better alternative, increases towards 1 as the size of the electorate grows assuming that each voter is more often right than wrong.
Several papers show that, under reasonable conditions, large groups are better trackers of the majority preference.
Applicability
The applicability of jury theorems, in particular, Condorcet's Jury Theorem (CJT) to democratic processes is debated, as it can prove majority rule to be a perfect mechanism or a disaster depending on individual competence. Recent studies show that, in a non-homogeneous case, the theorem's thesis does not hold almost surely (unless weighted majority rule is used with stochastic weights that are correlated with epistemic rationality but such that every voter has a minimal weight of one).
Further reading
Law of large numbers: a mathematical generalization of jury theorems.
Evolution in collective decision making.
Realizing Epistemic Democracy: a criticism on the assumptions of jury theorems.
The Epistemology of Democracy: a comparison of jury theorems to two other epistemic models of democracy: experimentalism and Diversity trumps ability.
References
Probability theorems
Voting theory | Jury theorem | [
"Mathematics"
] | 4,169 | [
"Theorems in probability theory",
"Mathematical theorems",
"Mathematical problems"
] |
67,755,416 | https://en.wikipedia.org/wiki/Padstool%20%28signage%29 | Bicycle mushroom (Dutch: ) is a form of rural wayfinding signage for cyclists, in use in the Netherlands. They are named for their toadstool-like shape; "paddenstoel" first came into use as a nickname around 1921.
Use
Padstools are considered complementary to conventional signs on tall poles. In built-up areas, pole signs are preferred, but in natural areas such as moors, dunes, and woods, padstool signs are preferred. In natural areas, padstools are sufficiently visible to be spotted and read by the passing cyclist, without being so visible from far off that they spoil the views of the landscape.
Cyclists can look down on padstool signs, rather than having to look up away from the path. The signs are designed to be read quickly; there is a principle in the Netherlands that cyclists should not be slowed or stopped, even to read signage. A constant speed is more comfortable and efficient, and makes for shorter travel times.
History
The early twentieth century saw a dramatic increase in the number of cars; in 1920 there were about three thousand of them in the Netherlands. Cyclists' objections lead to the development of separate bike paths (paths deliberately made too narrow for cars), and these paths needed their own signage.
The Algemene Nederlandsche Wielrijdersbond (ANWB), disliking the cluttering of natural landscapes with pole-mounted bike signage, ran a prize competition in 1918 for a better design, intended to be locally-produced. Three prototypes were set up on the heath of Laren in early 1919. The winning design was by Johannes Hendrik Willem Leliman, a house architect from Baarn. The first twelve padstools were installed between Laren and Baarn in 1919, by the local Cycle Path Society and the ANWB, two closely-entwined organizations. In 1920, 13 more were installed, and by 1975 there were 32 hundred padstools. In 2019, there were about six thousand padstools in the Netherlands, clustered in certain areas.
From 2000, the ANWB gradually ceased being responsible for padstools, and in 2012, they became the responsibility of the Nationale Bewegwijzeringsdienst. The ANWB's historian attributes this to conflict with the Dutch transport minister in 1999, and says that the transfer has led to a decrease in the quality of maintenance.
Despite widespread use of satellite navigation, the signs were still widely used as of 2020. Unlike the newer numbered-node signs, they generally give local placenames, and so the two are used together.
Design
The design has been described as simple to make, vandalproof, and inexpensive.
Padstools are generally made of concrete; this design choice was initially made partly because of the shortage of iron after World War I (earlier bike signs, from 1894, were made of metal). The early padstools were set into the ground, over a meter deep, and some weighed over 200 kilograms (the original design was 145 kilograms, set 1.5m deep, and required a team of three to install). By the 2020s, some padstools were still made of concrete, but some new designs were made of metal or organic-fiber-reinforced composites: coconut, hemp, flax, and jute fibers in resin, with development of more sustainable resins underway. The lightest weighed 10kg.
Initially the directions were painted directly onto the concrete, but in 1927 the ANWB developed a steel cap with a hole in top that screwed onto a central nut. This was easier to maintain in good condition.
Since 2003, the fietspadstool's colouring has been standardized, the cap being red with white sign areas. The lettering was likewise standardized to red, in a typeface designed by Gerard Unger, and experimentally found to be the fastest to read. These changes met with strong reactions and controversy.
In culture
Fietspadstools have been called "iconic", and are associated with Dutch bicycle culture. The ANWB considers them an icon of the ANWB, and has often used images of fietspadstools in ads.
See also
Cycling in the Netherlands
Numbered-node cycle network, a complementary signage system
References
Cycling infrastructure in the Netherlands
Traffic signs
Signage
Cycling infrastructure
Concrete | Padstool (signage) | [
"Engineering"
] | 894 | [
"Structural engineering",
"Concrete"
] |
67,756,829 | https://en.wikipedia.org/wiki/Rope%20bed | A rope bed is a type of platform bed in which the sleeper (and mattress) is supported by a lattice of rope, rather than wooden slats.
In cold climates, a rope bed would be topped with one or more insulating pailasses or bedticks, which would traditionally be stuffed with straw, chaff, or down feathers. It might also have a canopy hung with warm curtains. Modernly, they may be topped by a thin futon (a form of bedtick) or other roll-up mattress (see mattress topper).
In the sixteenth century (England?), bedmats of woven or plaited rush were often laid on the widely-spaced ropes, and the bedticks were laid on the mats. This stopped them from bulging between the ropes.
Rope beds need to be tightened regularly (with a bed wrench, and sometimes with wedges) as they sag. They must also be re-strung occasionally; re-stringing reduces sag and evens out wear. When fully or partly unstrung, rope beds can be packed flat for transport. The need to tighten bedcords has been said to be the origin of the English phrase "sleep tight", but some etymologists disagree.
See also
Charpai (warm-climate version)
Bedtick
Platform bed
Murphy bed; some are rope (or wire) beds
References
Beds
Portable furniture | Rope bed | [
"Biology"
] | 290 | [
"Beds",
"Behavior",
"Sleep"
] |
67,757,719 | https://en.wikipedia.org/wiki/Vaccinator | A vaccinator is a person who gives injections of a vaccine to people. Vaccinators require the skills of knowing where to inject the needle into the recipient as well as preparing the substance to be injected.
Under normal conditions, routine inoculations can be given by one’s healthcare provider, at a pharmacy, or at special clinics set up in a community. But when a mass vaccination effort is being undertaken, such as during a pandemic, people of various qualifying occupations may be sought specifically for the role as vaccinators due to high demand. Some of them may work full time at the job; others could do so part time in addition to their regular occupation. Some retirees may also work part-time.
Training
Training to be a vaccinator does not only require the skills to give an injection. Training is also needed in the storage and preparation of the materials used to give the shots of varying brands, which have differing requirements. Anaphylaxis training is a part of vaccinator training in some places.
Qualifying occupations
The following are some of the occupations that qualify a person to work as a vaccinator, which vary by location:
Dentist
Medical assistant
Medical student
National guard
Nurse
Nursing student
Paramedic
Pharmacist
Physician
Physician assistant
Veterinarian
Veterinary assistant
See also
Vaccination
Vaccine
List of vaccine topics
References
Health care occupations
Vaccination | Vaccinator | [
"Biology"
] | 287 | [
"Vaccination"
] |
67,758,077 | https://en.wikipedia.org/wiki/National%20Association%20for%20Environmental%20Education | The UK National Association for Environmental Education (NAEE) is one of the earliest environmental education non-profit organizations in the United Kingdom formed in 1960 as the National Rural Studies Association, and since 1971 operating under its current name.
Its mission is promoting environmental education in all forms, as well as supporting educators in their work, to make the future of our planet more sustainable. It provides resources and training of teachers and non-formal educators interested in teaching sustainability in their classes and developing a sustainability-oriented curriculum, in particular focusing on early education, and with a particular emphasis on local context education. It is the only association in the UK that is run by educators for their peers.
It is registered as a charity organization and publishes a triannual practitioner journal, Environmental Education. Since 2017 NAEE is running a fellowship program in recognition of individuals, who make a contribution to environmental education. It is also offering bursaries to carry out outdoors environmental education.
Its current President is Justin Dillon, Professor of Science and Environmental Education at University College London. The board of trustees is chaired by Paul Vare, and Nina Hatch is Executive Director.
References
Environmental education in the United Kingdom
Non-profit organisations based in the United Kingdom
Environmental education
Environmental organisations based in the United Kingdom
1950 establishments in the United Kingdom | National Association for Environmental Education | [
"Environmental_science"
] | 259 | [
"Environmental education",
"Environmental social science"
] |
67,759,250 | https://en.wikipedia.org/wiki/NGC%205198 | NGC 5198 is an elliptical galaxy in the constellation Canes Venatici. It was discovered by the astronomer William Herschel on May 12, 1787.
References
External links
Canes Venatici
5198
Elliptical galaxies | NGC 5198 | [
"Astronomy"
] | 47 | [
"Canes Venatici",
"Constellations"
] |
55,015,317 | https://en.wikipedia.org/wiki/Aql%20%28company%29 | aql is a telecommunications company based in Leeds, UK. It is principally known for operating carrier neutral data centres, and for providing services relating to colocation, mobile messaging, IP telephony, and secure mobile connectivity for the internet of things (IoT).
The company's head office is located at the historic Salem Chapel in Hunslet, Leeds.
Company history
aql was founded in 1998 by former University of Leeds lecturer and Ministry of Defence communications specialist Professor Adam Beaumont as a domain name registrar and email and web hosting company.
By 2003, aql had expanded into wholesale telecommunications, supplying UK phone numbers to the broadband industry to support IP telephony/VoIP services, providing mobile messaging services and supplying wholesale messaging platforms to international and UK networks. The company is responsible for more than 94 million numbers on 42 different telecoms networks. It also hosts 40 million UK numbers for voice services.
Beaumont purchased Salem Chapel in 2009. The Grade II listed building was renovated and restored to house aql's head office, including two data centres, an exhibition space and a conference facility.
The firm had a turnover of £7 million and employed around 40 people in 2013.
Also in 2013, aql announced plans to invest £43 million to build a data centre on the former site of Yorkshire Chemicals in Hunslet, Leeds.
The company acquired a 57,000 sq ft former council building located at South Point, Leeds for around half a million pounds in 2015. The company announced plans to convert the site into another data centre.
In September 2015, aql purchased Isle of Man-based BlueWave Communications following the death of its founder, former The Apprentice contestant Stuart Baggs.
In March 2017, aql won the contract to serve the UK's universities, colleges and teaching hospitals with secure data storage via a framework contract operated by Jisc.
aql unveiled its first autonomous vehicle in April 2018, and announced a consortium of partners, including Gulf Oil, the University of Leeds, Leeds and Bradford city councils, Citu and CitiPark, to trial the vehicles in Leeds.
IXLeeds
Since 2011, one of aql's Salem Chapel data centres has housed the Leeds internet exchange, IXLeeds. IXLeeds is the UK's only fully independent internet exchange outside London. Beaumont co-founded the exchange, and serves as company secretary.
Leeds' WiFi telephone boxes
In 2013, aql reconditioned 24 Giles Gilbert Scott-designed red telephone boxes. The boxes were painted blue, converted into solar-powered free WiFi access points, and placed around Leeds city centre.
The boxes are known as Leeds Electronic Ordnance and Digital Information System, or LEODIS, after the old English name for the city of Leeds.
In July 2017, aql announced that the initiative had seen 100,000 unique users since its introduction.
Sponsorship and local support
In May 2017, aql was announced as the Communications Sponsor for Lendy Cowes Week 2017. In addition to sponsoring the event, aql competed in the 50-nautical mile race around the Isle of Wight. CEO Adam Beaumont was joined at the helm by blind sailor Lucy Hodges . In June 2018 it was announced that aql had struck a 5-year deal to continue sponsoring the event.
Also in May 2017, aql was among the local companies to offer support and financial backing to Leeds' bid to become European Capital of Culture 2023.
Since 2000, aql has sponsored a live webcam overlooking Millennium Square, Leeds.
The company is a patron of Leeds Community Foundation.
References
External links
aql
IXLeeds
1998 establishments in England
British companies established in 1998
Companies based in Leeds
Data centers
Technology companies established in 1998
Telecommunications companies established in 1998
Telecommunications companies of the United Kingdom | Aql (company) | [
"Technology"
] | 773 | [
"Data centers",
"Computers"
] |
55,016,824 | https://en.wikipedia.org/wiki/Electromagnetism%20uniqueness%20theorem | The electromagnetism uniqueness theorem states the uniqueness (but not necessarily the existence) of a solution to Maxwell's equations, if the boundary conditions provided satisfy the following requirements:
At , the initial values of all fields (, , and ) everywhere (in the entire volume considered) is specified;
For all times (of consideration), the component of either the electric field or the magnetic field tangential to the boundary surface ( or , where is the normal vector at a point on the boundary surface) is specified.
Note that this theorem must not be misunderstood as that providing boundary conditions (or the field solution itself) uniquely fixes a source distribution, when the source distribution is outside of the volume specified in the initial condition. One example is that the field outside a uniformly charged sphere may also be produced by a point charge placed at the center of the sphere instead, i.e. the source needed to produce such field at a boundary outside the sphere is not unique.
See also
Maxwell's equations
Green's function
Surface equivalence principle
Uniqueness theorem
References
Specific
Vector calculus
Physics theorems
Uniqueness theorems | Electromagnetism uniqueness theorem | [
"Physics",
"Materials_science",
"Mathematics"
] | 226 | [
"Materials science stubs",
"Mathematical theorems",
"Equations of physics",
"Mathematical problems",
"Uniqueness theorems",
"Electromagnetism stubs",
"Physics theorems"
] |
55,017,999 | https://en.wikipedia.org/wiki/Drainage%20tunnel | A drainage tunnel, called an emissary in ancient contexts, is a tunnel or channel created to drain water, often from a stagnant or variable-depth body of water. It typically leads to a lower stream or river, or to a location where a pumping station can be economically run. Drainage tunnels have frequently been constructed to drain mining districts or to serve drainage districts.
Etymology
Emissary comes from Latin emissarium, from ex and mittere 'to send out'.
Ancient world
The most remarkable emissaries carry off the waters of lakes surrounded by hills.
In ancient Greece, the waters of Lake Copais were drained into the Cephisus; they were partly natural and partly artificial. In 480 BC, Phaeax built drains at Agrigentum in Sicily: they were admired for their sheer size, although the workmanship was crude.
The ancient Romans excelled in the construction of emissaries, as in all their hydraulic works, and remains are extant showing that lakes Trasimeno, Albano and Nemi were all drained by means of emissaries. The case of Lake Fucino is remarkable in two ways: the attempt to drain it was one of the rare failures of Roman engineering, and the emissary is now completely above ground and open to inspection. Julius Caesar is said to have first conceived the idea of this stupendous undertaking (Suet. Jul. 44). Claudius inaugurated what was to have been a complete drainage scheme, the Tunnels of Claudius (Tac. Ann. xii.57), but the water level dropped by just 4 meters and stabilized, leaving the lake very much there. Hadrian tried it again, but failed; and it was not until 1878 that Lake Fucino was finally drained.
The initial text of this section was an abridgement from Smith's Dictionary of Greek and Roman Antiquities (1875 edition, public domain).
Modern examples
Modern examples of drainage tunnels include the Emisor Oriente Tunnel near Mexico City, as well as the Tunnel and Reservoir Plan in Chicago.
See also
Storm drain
External links
Emissarium, the full article in Smith's Dictionary
Walter Dragoni, Costanza Cambi, Field Trip Guidebook for "Hydraulic Structures in Ancient Rome", field trip of the 42nd Congress of the International Association of Hydrogeologists, Rome, September 2015. full text
Flood control
Roman aqueducts
Ancient Roman architectural elements
Hydraulic engineering | Drainage tunnel | [
"Physics",
"Chemistry",
"Engineering",
"Environmental_science"
] | 491 | [
"Hydrology",
"Physical systems",
"Flood control",
"Hydraulics",
"Civil engineering",
"Civil engineering stubs",
"Environmental engineering",
"Hydraulic engineering"
] |
55,018,276 | https://en.wikipedia.org/wiki/C26H35FO6 | {{DISPLAYTITLE:C26H35FO6}}
The molecular formula C26H35FO6 (molar mass: 462.558 g/mol) may refer to:
Amcinafal (also known as triamcinolone pentanonide)
Amelometasone
Molecular formulas | C26H35FO6 | [
"Physics",
"Chemistry"
] | 68 | [
"Molecules",
"Set index articles on molecular formulas",
"Isomerism",
"Molecular formulas",
"Matter"
] |
55,018,303 | https://en.wikipedia.org/wiki/C22H29ClO5 | {{DISPLAYTITLE:C22H29ClO5}}
The molecular formula C22H29ClO5 may refer to:
Alclometasone, a synthetic corticosteroid for topical dermatologic use
Icometasone, a synthetic glucocorticoid corticosteroid which was never marketed | C22H29ClO5 | [
"Chemistry"
] | 73 | [
"Isomerism",
"Set index articles on molecular formulas"
] |
55,018,327 | https://en.wikipedia.org/wiki/C28H34O6 | {{DISPLAYTITLE:C28H34O6}}
The molecular formula C28H34O6 (molar mass: 466.566 g/mol) may refer to:
Benzodrocortisone, or hydrocortisone 17-benzoate
Deoxygedunin
Molecular formulas | C28H34O6 | [
"Physics",
"Chemistry"
] | 69 | [
"Molecules",
"Set index articles on molecular formulas",
"Isomerism",
"Molecular formulas",
"Matter"
] |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.