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58,019,382 | https://en.wikipedia.org/wiki/96%20equal%20temperament | In music, 96 equal temperament, called 96-TET, 96-EDO ("Equal Division of the Octave"), or 96-ET, is the tempered scale derived by dividing the octave into 96 equal steps (equal frequency ratios). Each step represents a frequency ratio of , or 12.5 cents. Since 96 factors into 1, 2, 3, 4, 6, 8, 12, 16, 24, 32, 48, and 96, it contains all of those temperaments. Most humans can only hear differences of 6 cents on notes that are played sequentially, and this amount varies according to the pitch, so the use of larger divisions of octave can be considered unnecessary. Smaller differences in pitch may be considered vibrato or stylistic devices.
History and use
96-EDO was first advocated by Julián Carrillo in 1924, with a 16th-tone piano. It was also advocated more recently by Pascale Criton and Vincent-Olivier Gagnon.
Notation
Since 96 = 24 × 4, quarter-tone notation can be used and split into four parts.
One can split it into four parts like this:
C, C, C/C, C, C, ..., C, C
As it can become confusing with so many accidentals, Julián Carrillo proposed referring to notes by step number from C (e.g. 0, 1, 2, 3, 4, ..., 95, 0)
Since the 16th-tone piano has a 97-key layout arranged in 8 conventional piano "octaves", music for it is usually notated according to the key the player has to strike. While the entire range of the instrument is only C4–C5, the notation ranges from C0 to C8. Thus, written D0 corresponds to sounding C4 or note 2, and written A♭/G♯2 corresponds to sounding E4 or note 32.
Interval size
Below are some intervals in 96-EDO and how well they approximate just intonation.
Moving from 12-EDO to 96-EDO allows the better approximation of a number of intervals, such as the minor third and major sixth.
Scale diagram
Modes
96-EDO contains all of the 12-EDO modes. However, it contains better approximations to some intervals (such as the minor third).
See also
Musical temperament
Equal temperament
References
Further reading
Sonido 13, Julián Carrillo's theory of 96-EDO
Equal temperaments
Microtonality | 96 equal temperament | [
"Physics"
] | 498 | [
"Physical quantities",
"Musical symmetry",
"Logarithmic scales of measurement",
"Equal temperaments",
"Symmetry"
] |
58,019,819 | https://en.wikipedia.org/wiki/Pregnenolone%20%28medication%29 | Pregnenolone, sold under the brand name Enelone among others, is a medication and supplement as well as a naturally occurring and endogenous steroid. It is described as a neurosteroid and anti-inflammatory drug and was used in the treatment of rheumatoid arthritis and soft-tissue rheumatism in the 1950s and is no longer prescribed today, but remains available as a supplement. Pregnenolone can be taken by mouth, as a topical medication, or by injection into muscle.
Pregnenolone is promoted online with false claims that it can treat a variety of health conditions including cancer, arthritis and multiple sclerosis.
Medical uses
Pregnenolone was approved for use as a pharmaceutical medication in the treatment of rheumatoid arthritis and soft-tissue rheumatism in the 1950s. It is no longer used today.
Available forms
Pregnenolone acetate was available as Enelone in the form of 100 mg oral tablets and as a 100 mg/mL crystalline aqueous suspension in 10 mL vials.
Pharmacology
Pregnenolone is a neurosteroid. It is a negative allosteric modulator of the CB1 receptor, a ligand of the microtubule-associated protein 2 (MAP2), and an agonist of the pregnane X receptor. Pregnenolone has no progestogenic, corticosteroid, estrogenic, androgenic, or antiandrogenic activity. In addition to its own activities, pregnenolone is a precursor for other neurosteroids such as pregnenolone sulfate, allopregnanolone, and pregnanolone and for steroid hormones.
Pregnenolone has low bioavailability and is subject to high metabolism. Oral administration of 50 or 100 mg pregnenolone has been found to have minimal or negligible effect on urinary levels of testosterone and testosterone metabolites, including of androsterone, etiocholanolone, 5β-androstanediol, androstadienol, and androstenol (and/or their conjugates), and this suggests that only a small amount of pregnenolone is converted into testosterone. This is in accordance with findings on the conversion of DHEA into testosterone, in which only 1.5% of an oral dose of DHEA was found to be converted into testosterone. In contrast to the androstanes, 50 or 100 mg oral pregnenolone has been found to significantly and in fact "strongly" increase urinary levels of the progesterone metabolites pregnanediol and pregnanolone (and/or their conjugates), whereas pregnanetriol was unaffected. Unlike the case of oral administration, transdermal administration of 30 mg/day pregnenolone cream has not been found to affect urinary levels of metabolites of any other steroids, including of progesterone. Intranasal administration of pregnenolone was found to have low bioavailability of around 23%.
Sripada et al. reported that oral pregnenolone is preferentially metabolized into the neurosteroid allopregnanolone rather than into other steroids such as DHEA or cortisol. In further research by their group, a single 400 mg dose of oral pregnenolone at 3 hours post-administration was found to result in a 3-fold elevation in serum levels of pregnenolone and a 7-fold increase in allopregnanolone levels. Pregnanolone levels increased by approximately 60% while DHEA levels decreased non-significantly by approximately 5% and cortisol levels were not affected. Another study found that allopregnanolone levels were increased by 3-fold at 2 hours post-administration following a single 400 mg oral dose of pregnenolone.
In addition to allopregnanolone, pregnenolone acts as a prodrug of pregnenolone sulfate. However, pregnenolone sulfate does not cross the blood–brain barrier.
Chemistry
Pregnenolone, also known as 5-pregnenolone or as pregn-5-en-3β-ol-20-one, is a naturally occurring pregnane steroid and a derivative of cholesterol. Related steroids include pregnenolone sulfate, 3β-dihydroprogesterone (4-pregnenolone), progesterone, allopregnanolone, and pregnanolone.
Derivatives
A few synthetic ester derivatives of pregnenolone exist. These include pregnenolone acetate (Antofin, Previsone, Pregno-Pan) and pregnenolone succinate (Panzalone, Formula 405). Prebediolone acetate (Acetoxanon, Acetoxy-Prenolon, Artisone, Artivis, Pregnartrone, Sterosone), the 21-acetate ester of 21-hydroxypregnenolone, also exists. These esters are all described as glucocorticoids similarly to pregnenolone.
The 3β-methyl ether of pregnenolone, 3β-methoxypregnenolone (MAP-4343), retains similar activity to pregnenolone in regard to interaction with MAP2, and is under development for potential clinical use for indications such as the treatment of brain and spinal cord injury and depressive disorders.
History
Pregnenolone was first synthesized by Adolf Butenandt and colleagues in 1934. It was first used in medicine, as an anti-inflammatory medication, in the 1940s.
Society and culture
Generic names
Pregnenolone is the generic name of the drug and its , , , and .
Brand names
Pregnenolone has been marketed in the past under a variety of brand names including Arthenolone, Bina-Skin, Enelone, Natolone, Pregnetan, Pregneton, Pregnolon, Prenolon, Prenolone, Regnosone, Sharmone, and Skinostelon.
Availability
Pregnenolone is no longer marketed as a medication, but remains available as a supplement.
Alternative medicine
Pregnenolone has been promoted online with claims it can treat a variety of diseases including multiple sclerosis, arthritis, and cancer, but such claims are not backed by evidence.
Research
pregnenolone is being researched for possible therapeutic applications, but its poor bioavailability makes its prospects for usefulness low. Pregnenolone is available as an over-the-counter supplement, for instance in the United States.
See also
List of unproven and disproven cancer treatments
References
Abandoned drugs
Anti-inflammatory agents
CB1 receptor antagonists
Glycine receptor agonists
Ketones
Neurosteroids
Pregnane X receptor agonists
Pregnanes
Prodrugs
Secondary alcohols
Sigma agonists | Pregnenolone (medication) | [
"Chemistry"
] | 1,463 | [
"Ketones",
"Functional groups",
"Drug safety",
"Prodrugs",
"Chemicals in medicine",
"Abandoned drugs"
] |
58,021,305 | https://en.wikipedia.org/wiki/Brain-specific%20homeobox | Brain-specific homeobox is a protein that in humans is encoded by the BSX gene.
Structure and expression pattern
Bsx is an evolutionarily highly-conserved homeodomain-containing transcription factor that belongs to the ANTP-class. In mouse it has been shown to be expressed in the telencephalic septum, pineal gland, the mammillary bodies and arcuate nucleus.
Function in the hypothalamus
In the hypothalamic arcuate nucleus, Bsx has been demonstrated to be necessary for normal expression levels of the two orexigenic neuropeptides Agouti-related peptide and Neuropeptide Y.
Function in the pineal gland
In the pineal gland of the clawed frog Xenopus, Bsx is expressed following the circadian rhythm and controls photoreceptor cell differentiation. In zebrafish Bsx is required for normal development of all cell types within the pineal gland, including melatonin-releasing pinealocytes, photoreceptor cells and leftwards migrating parapineal cells, which in zebrafish are crucial for the establishment of brain asymmetry.
References
Brain
Proteins
Transcription factors
Genes
Molecular biology | Brain-specific homeobox | [
"Chemistry",
"Biology"
] | 248 | [
"Biomolecules by chemical classification",
"Gene expression",
"Signal transduction",
"Induced stem cells",
"Molecular biology",
"Biochemistry",
"Proteins",
"Transcription factors"
] |
58,022,154 | https://en.wikipedia.org/wiki/Vildagliptin/metformin | Vildagliptin/metformin, sold under the brand name Eucreas among others, is a fixed-dose combination anti-diabetic medication for the treatment of type 2 diabetes. It was approved for use in the European Union in November 2007, and the approval was updated in 2008. It combines 50 mg vildagliptin with either 500, 850, or 1000 mg metformin.
The most common side effects include nausea (feeling sick), vomiting, diarrhea, abdominal (tummy) pain and loss of appetite.
Medical uses
Vildagliptin/metformin is indicated in the treatment of type-2 diabetes mellitus:
it is indicated in the treatment of adults who are unable to achieve sufficient glycaemic control at their maximally tolerated dose of oral metformin alone or who are already treated with the combination of vildagliptin and metformin as separate tablets.
it is indicated in combination with a sulphonylurea (i.e. triple combination therapy) as an adjunct to diet and exercise in patients inadequately controlled with metformin and a sulphonylurea.
it is indicated in triple combination therapy with insulin as an adjunct to diet and exercise to improve glycaemic control in patients when insulin at a stable dose and metformin alone do not provide adequate glycaemic control.
References
External links
Adamantanes
Biguanides
Carboxamides
Combination diabetes drugs
Dipeptidyl peptidase-4 inhibitors
Drugs with unknown mechanisms of action
Guanidines
Nitriles
Drugs developed by Novartis
Pyrrolidines
Tertiary alcohols | Vildagliptin/metformin | [
"Chemistry"
] | 341 | [
"Nitriles",
"Guanidines",
"Functional groups"
] |
73,345,230 | https://en.wikipedia.org/wiki/Edmund%20R.%20Malinowski | Edmund R. Malinowski (October 1932 – February 2020) was an American professor of chemistry and is considered to be one of the great pioneers of the field of chemometrics. He published over 70 research papers and his 1980 book, Factor Analysis in Chemistry is acknowledged to be the first text on factor analysis applied to chemistry. Malinowski is credited with having an “enormous impact” on the field of chemometrics and the researchers who followed him.
Education
Edmund R. Malinowski was born in October 1932, in Mahanoy City, PA. He obtained a Bachelor of Science in chemistry from The Pennsylvania State University in 1954. He obtained both a MS degree (1956) and PhD (1961) in physical chemistry at Stevens Institute of Technology, and was a Robert Crooks Stanley Graduate Fellow as a student during those years.
Career
Malinowski went on to a long, distinguished academic career at the Stevens Institute of Technology. He joined the Institute’s chemistry faculty in 1965 and became a full professor there in 1970. The Institute awarded him the 1977 Jess H. Research Award for his work on the theory and applications of factor analysis, and the 1994 Henry Morton Distinguished Professor Award, which honors excellence in research and teaching. He retired from Stevens Institute of Technology in 1997. Paul Gemperline summarized Malinowski's work at the time of his retirement in a Journal of Chemometrics editorial: "Over the course of his career as a chemist and educator he has published over 70 research papers and presented over 200 papers at seminars and professional meetings."
Research
Before chemometrics was identified and named as a field of research and study by Kowalski and Wold in 1974, Malinowski was publishing work that would be regarded as chemometrics. His first paper on factor analysis was published in 1966.
Influence and recognition
According to Paul Gemperline, prior to Malinowski's 1980 book, Factor Analysis in Chemistry, "factor analysis and principal component analysis were virtually unknown in the world of chemistry." Gemperline goes on to say Malinowski's book was "influential" not only because of the "timely" introduction of these topics but also because he had a "clear writing style … that chemists could understand". Malinowski was recognized for being generous in his acknowledgement and recognition of the work of others, citing their work in his own presentations and publications, which helped younger researchers to be successful.
Malinowski was recognized by his peers as a leader in the field of chemometrics in 1998 when he was awarded the Galactic Industries Award for Achievements in Chemometrics. After his 1997 retirement the Journal of Chemometrics published a special issue in Malinowski’s honor.
List of Honors and Awards
1957 – 1959: Robert Crooks Stanley Graduate Fellowship, Stevens Institute of Technology
1977: Jess H. Research Award, Stevens Institute of Technology,
1994: Henry Morton Distinguished Professor Award, Stevens Institute of Technology
1997: Special Issue: In Honor of Professor Malinowski's Retirement, Journal of Chemometrics,
1998: Galactic Industries Award for Achievements in Chemometrics
References
1932 births
2020 deaths
American chemists
Chemometricians
Pennsylvania State University alumni
Stevens Institute of Technology alumni
Stevens Institute of Technology faculty
People from Mahanoy City, Pennsylvania | Edmund R. Malinowski | [
"Chemistry"
] | 672 | [
"Analytical chemists",
"Chemometricians"
] |
73,348,452 | https://en.wikipedia.org/wiki/Ambient%20IoT | Ambient IoT, from ambient and Internet of things, is a concept originally coined by 3GPP that is used in the technology industry referring to an ecosystem of a large number of objects in which every item is connected into a wireless sensor network using low-cost self-powered sensor nodes. Bluetooth SIG has assessed the total addressable market of Ambient IoT to be more than 10 trillion devices across different verticals.
The applications of Ambient IoT include making supply chains for food and medicine more efficient and sustainable, protecting from counterfeiting and delivering the data required for advanced transportation and smart city initiatives. Ambient IoT has been called "the original vision for the IoT" by U.S. Department of Commerce IoT Advisory Board chair Benson Chan.
Standards for Ambient IoT are being considered by 3GPP, IEEE and Bluetooth SIG.
References
Internet of things
Ambient intelligence | Ambient IoT | [
"Technology"
] | 181 | [
"Computing and society",
"Ambient intelligence"
] |
73,350,818 | https://en.wikipedia.org/wiki/Jos%C3%A9%20Bonilla%20%28astronomer%29 | José Árbol y Bonilla (February 5, 1853 – 1920) was a Mexican astronomer, engineer, and astrophotographer.
He is most known for the 1883 Bonilla observation, in which he observed and photographed hundreds objects passing in front of the Sun through a telescope. The identity of the objects he observed remained unknown until 2011 when they were identified as comet fragments.
The photographs that Bonilla took of his are some of the earliest examples of unidentified flying object photography.
Early life
José Árbol y Bonilla was born on February 5, 1853, in Ciudad de Zacatecas, Zacatecas, Mexico. His parents were Francisco Árbol y Bonilla and María de Jesús Carrillo.
He studied topographical engineering in Zacatecas before being granted a scholarship to the Escuela de Minas in Mexico City by Zacatecas governor Gabriel García in 1873. He studied civil engineering at Escuela de Minas and completed the three-year course in one year. For this accomplishment, he won the 1875 Premio al Mérito (Award of Merit) from President Sebastián Lerdo de Tejada.
Career
After his graduation in 1874, Bonilla returned to Zacatecas and became a teacher at the García Literary Institute where he also began studying science and technology. In 1879, he moved to Paris to study celestial photography at the Paris Astronomical Observatory where he became a member of the Flammarion Scientific Society of Paris.
On December 6, 1882, the Astronomical Observatory in the State of Zacatecas opened in Ciudad de Zacatecas with Bonilla acting as director. It was the first major astronomical observatory in Mexico to be opened outside of Mexico City. It was while he was director of the Zacatecas observatory when he made his famous Bonilla observation in 1883.
Bonilla would serve as director of the Zacatecas observatory until 1911 when he became the director of the National School of Arts and Crafts in Mexico City.
Bonilla observation
On August 12, 1883, Bonilla was preparing his telescope for observations when he observed multiple objects pass in front of the Sun. Over the course of the next day and a half, he took 447 photographs of the objects with wet plates.
Bonilla's observations first reached the public in 1886 when his findings were detailed in the January 1, 1886 edition of the French astronomical journal L’Astronomie. Bonilla had previously sent its founder, French physicist Camille Flammarion, his findings, which led to them being published after over two years of being kept private. The release of his work was questioned by Flammarion and others, who dismissed his findings as birds, insects, or dust.
In October 2011, researchers from the National Autonomous University of Mexico published a paper concluding that Bonilla's observation was actually fragments of a comet that had exploded and were passing in front of the sun.
Interest in the Bonilla observation was rekindled by UFO enthusiasts on the Internet as the observation was the first case of an unsolved photograph of an unidentified flying object, and a mystery that took 125 years to solve.
Personal life
Bonilla married Aurelia Hierro Alcántara in September 1878. They would have two kids together. José Bonilla died in 1920 in Mexico City.
References
Mexican astronomers
1853 births
1920 deaths
Astrophotographers
People from Zacatecas City | José Bonilla (astronomer) | [
"Astronomy"
] | 674 | [
"People associated with astronomy",
"Astrophotographers"
] |
73,354,217 | https://en.wikipedia.org/wiki/Bruce%20R.%20Kowalski | Bruce R. Kowalski (March 1942 – December 2012) was an American professor of analytical chemistry who is acknowledged by the world-wide scientific community to be one of the founders of the field of chemometrics. He was the founding editor of Journal of Chemometrics, and the founding director of the Center for Process Analytical Chemistry at University of Washington in Seattle. Kowalski and
Svante Wold formed the Chemometrics Society, which would later become the International Chemometrics Society.
Education
As an undergraduate, Kowalski attended Millikin University, double majoring in chemistry and mathematics. He completed his PhD in chemistry at University of Washington in 1969 under researcher Tom Isenhour.
Career
Early years
After obtaining his PhD, Kowalski worked briefly for Shell Development. He left Shell in 1971 for Lawrence Livermore Laboratory where he and C. F. Bender worked together to help develop Livermore's proprietary PATTRN data analysis system.
University professor
In 1972 he joined the chemistry faculty at Colorado State University as an assistant professor. He moved to the University of Washington in 1974 where he stayed until his retirement in 1999. He became a full professor in 1979 and an endowed professor of analytical chemistry in 1991. The chemistry department's newsletter, Chem Letter, reported that ten companies contributed to the endowment and that it was the first endowed professorship at the university "established through a consortium of industrial and state resources." Former graduate student David Duewer summarized Kowalski's accomplishments in the Journal of Chemometrics: "32 PhD and three MS students, over 230 research publications, editorials, chapters, and reports (32 in this journal) with 144 coauthors, more than 230 invited lectures, four patents, more than 50 quarters of undergrad and graduate sections spread over 18 courses, more than $22m in grants, and – not least – founder of this journal."
Director of CPAC
Kowalski served as the inaugural director of the Center for Process Analytical Chemistry (CPAC), established in 1984, at the University of Washington. Initially CPAC was a National Science Foundation (NSF) Industry-University Cooperative Research Center (IUCRC). It has since been renamed Center for Process Analysis and Control and has become self-sustaining. Writing for Analytical Chemistry, Alan Newman called CPAC the "brainchild" of Kowalski, who proposed the idea in 1982, and said in the field of analytical chemistry, "CPAC offers a unique model of how chemists can successfully forge bonds with industry, government, and allied academic disciplines to foster new ideas. At the same time, the center establishes a two-way flow of ideas between basic researchers in academia and scientists in industry and government."
Editor of Journal of Chemometrics
Kowalski was the founding editor of the Journal of Chemometics, the first issue of which came out in January 1987. The editorial of the first issue, written by Kowalski, Steven Brown and Bernard Vandeginst, explains that after 10 years of the founding of the field of chemometrics and 20 years of researchers actually doing chemometrics and having their publications "widely distributed through the literature," it was time for a journal "to bring together papers on how chemists use mathematics and statistics in their work in novel ways and also on potentially new tools that chemists may find useful in the future." After his death the journal published a special issue in his honor in May 2014. It also established the annual Kowalski Prize for the best theoretical and applied papers published in the journal in the two preceding years.
Company founder
Kowalski and colleague Gerald Erickson founded the chemometrics company, Infometrix, in Seattle in 1978.
A Founder of Chemometrics
A foundational discourse on the field of chemometrics by Kowalski, "Chemometrics: Views and Propositions," was published in 1975. In it he defines chemometrics as "any and all methods that can be used to extract useful chemical information from raw data." Kowalski takes up the question of what constitutes "new and viable research" in the field and goes on to explain how his training as an analytical chemist and experience with pattern recognition as a tool for chemical analysis has influenced his opinion about this. The included letter to a "prospective chemometrician," signed by Kowalski and Svante Wold, asserts "chemometrics should not involve theoretical calculations, but should deal primarily with the extraction of useful chemical information from measured data." The letter announces that an informal "Chemometrics Society" was begun on June 10, 1974, describes the purposes of the society and invites the interested researcher to join. Kowalski's research group was given as the Laboratory for Chemometrics, Department of Chemistry, University of Washington, and Wold's research group was given as Research Group for Chemometrics, Institute of Chemistry, Umea University, Sweden. This society, formed from Kowalksi's and Wold's two research groups, eventually became the International Chemometrics Society.
Wold had coined the term "chemometrics" for a grant application in 1971. He and Kowalski first met in 1973 at a symposium in Tucson, Arizona, and after discussion, Kowalski agreed to use the term to describe his own research as well. Wold says Kowalski became "both a strong proponent and spokesman for this new field."
Research
In his presentation at a 2019 chemometrics conference in France, Steven Brown called Kowalski the "father" of the following areas of chemometrics: 'NAS methods (with K. Booksh), multiway methods (with E. Sanchez), heuristics in chemistry (with C. Bender), multi-algorithms in chemistry for “big data” ( > 16 kb)'.
Responding to a question posed during a 1988 interview, Kowalski felt that his most impactful paper to date was the one he wrote with C. Bender, published in the Journal of the American Chemical Society in 1972, "Pattern recognition. A Powerful approach to interpreting chemical data". Wold categorized this publication as a "seminal" paper in pattern recognition in chemistry.
Kowalski's areas of interest outside of chemometrics were analytical instrumentation, remote sensing, process modeling, and chemical sensors in process analysis and control.
Personal life
In his spare time Kowalski enjoyed horse-breeding and riding, sailing, hiking and backpacking, his Harley-Davidison motorcycle and skiing. According to Chemical & Engineering News, "After his retirement in 1999, Kowalski joined the Fort Lewis Mesa fire department in Durango, Colo., where he specialized in the handling of hazardous materials. Kowalski and his companion dog, Chaco-Bob, were a key part of the district’s canine search and rescue program."
Legacy
The Society for Applied Spectroscopy was selected by Kowalski's family to administer an award in Kowalski's name, the Bruce R. Kowalski Award in Chemometrics - Administered by the Society for Applied Spectroscopy, "to honor the legacy of Professor Kowalski by recognizing outstanding young researchers in the field of chemometrics and by extension, for advanced mathematical and/or statistical methods in chemistry."
The University of Washington has three scholarships set up in Kowalski's honor, the Kowalski Excellence in Graduate Education Fund, Bruce Kowalski Endowed Fund for Graduate Student Support, and the chemistry department's Bruce R. Kowalski Endowed Fund in Chemistry.
In 2015 the American Chemical Society published a symposium series in Kowalski's honor, 40 Years of Chemometrics – From Bruce Kowalski to the Future.
The Kowalski Prize, worth $1,000, is given annually by the Journal of Chemometrics, alternating between "the 'best theoretical paper' and 'best applied paper' published in the journal in the previous two years."
List of Honors and Awards
1985: Pittsburgh Analytical Chemistry Award
1988: Malcolm E. Pruitt Award from the Council for Chemical Research
1989: Theophilus Redwood Endowed Lectureship from the Royal Society of Chemistry
1991: Endowed Professor of Analytical Chemistry, University of Washington
1993: Torbern Bergman Medal from the Swedish Chemical Society’s analytical division
References
External links
CPAC
IUCRC
Infometrix
Chemometricians
Analytical chemists
University of Washington faculty
American chemists
Millikin University alumni
University of Washington alumni
1942 births
2012 deaths | Bruce R. Kowalski | [
"Chemistry"
] | 1,692 | [
"Analytical chemists",
"Chemometricians"
] |
73,354,598 | https://en.wikipedia.org/wiki/Aliasing%20%28factorial%20experiments%29 | In the statistical theory of factorial experiments, aliasing is the property of fractional factorial designs that makes some effects "aliased" with each other – that is, indistinguishable from each other. A primary goal of the theory of such designs is the control of aliasing so that important effects are not aliased with each other.
In a "full" factorial experiment, the number of treatment combinations or cells (see below) can be very large. This necessitates limiting observations to a fraction (subset) of the treatment combinations.
Aliasing is an automatic and unavoidable result of observing such a fraction.
The aliasing properties of a design are often summarized by giving its
resolution. This measures the degree to which the design avoids aliasing between main effects and important interactions.
Fractional factorial experiments have long been a basic tool in
agriculture, food technology, industry, medicine and public health, and the social and behavioral sciences.
They are widely used in exploratory research, particularly in screening experiments, which have applications in industry, drug design and genetics. In all such cases, a crucial step in designing such an experiment is deciding on the desired aliasing pattern, or at least the desired resolution.
As noted below, the concept of aliasing may have influenced the identification of an analogous phenomenon in signal processing theory.
Overview
Associated with a factorial experiment is a collection of effects. Each factor determines a main effect, and each set of two or more factors determines an interaction effect (or simply an interaction) between those factors. Each effect is defined by a set of relations between cell means, as described below. In a fractional factorial design, effects are defined by restricting these relations to the cells in the fraction. It is when the restricted relations for two different effects turn out to be the same that the effects are said to be aliased.
The presence or absence of a given effect in a given data set is tested by statistical methods, most commonly analysis of variance. While aliasing has significant implications for estimation and hypothesis testing, it is fundamentally a combinatorial and algebraic phenomenon. Construction and analysis of fractional designs thus rely heavily on algebraic methods.
The definition of a fractional design is sometimes broadened to allow multiple observations of some or all treatment combinations – a multisubset of all treatment combinations. A fraction that is a subset (that is, where treatment combinations are not repeated) is called simple. The theory described below applies to simple fractions.
Contrasts and effects
In any design, full or fractional, the expected value of an observation in a given treatment combination is called a cell mean, usually denoted using the Greek letter μ. (The term cell is borrowed from its use in tables of data.)
A contrast in cell means is a linear combination of cell means in which the coefficients sum to 0. In the 2 × 3 experiment illustrated here, the expression
is a contrast that compares the mean responses of the treatment combinations 11 and 12. (The coefficients here are 1 and –1.)
The effects in a factorial experiment are expressed in terms of contrasts. In the above example, the contrast
is said to belong to the main effect of factor A as it contrasts the responses to the "1" level of factor with those for the "2" level. The main effect of A is said to be absent if this expression equals 0. Similarly,
and
are contrasts belonging to the main effect of factor B. On the other hand, the contrasts
and
belong to the interaction of A and B; setting them equal to 0 expresses the lack of interaction. These designations, which extend to arbitrary factorial experiments having three or more factors, depend on the pattern of coefficients, as explained elsewhere.
Since it is the coefficients of these contrasts that carry the essential information, they are often displayed as column vectors. For the example above, such a table might look like this:
The columns of such a table are called contrast vectors: their components add up to 0. While there are in general many possible choices of columns to represent a given effect, the number of such columns — the degrees of freedom of the effect — is fixed and is given by a well-known formula. In the 2 × 3 example above, the degrees of freedom for , and the interaction are 1, 2 and 2, respectively.
In a fractional factorial experiment, the contrast vectors belonging to a given effect are restricted to the treatment combinations in the fraction. Thus, in the half-fraction {11, 12, 13} in the 2 × 3 example, the three effects may be represented by the column vectors in the following table:
The consequence of this truncation — aliasing — is described below.
Definitions
The factors in the design are allowed to have different numbers of levels, as in a factorial experiment (an asymmetric or mixed-level experiment).
Fix a fraction of a full factorial design. Let be a set of contrast vectors representing an effect (in particular, a main effect or interaction) in the full factorial design, and let consist of the restrictions of those vectors to the fraction. One says that the effect is
preserved in the fraction if consists of contrast vectors;
completely lost in the fraction if consists of constant vectors, that is, vectors whose components are equal; and
partly lost otherwise.
Similarly, let and represent two effects and let and be their restrictions to the fraction. The two effects are said to be
unaliased in the fraction if each vector in is orthogonal (perpendicular) to all the vectors in , and vice versa;
completely aliased in the fraction if each vector in is a linear combination of vectors in , and vice versa; and
partly aliased otherwise.
Finney and Bush introduced the terms "lost" and "preserved" in the sense used here. Despite the relatively long history of this topic, though, its terminology is not entirely standardized. The literature often describes lost effects as "not estimable" in a fraction, although estimation is not the only issue at stake. Rao referred to preserved effects as "measurable from" the fraction.
Resolution
The extent of aliasing in a given fractional design is measured by the resolution of the fraction, a concept first defined by Box and Hunter:
A fractional factorial design is said to have resolution if every -factor effect is unaliased with every effect having fewer than factors.
For example, a design has resolution if main effects are unaliased with each other (taking , though it allows main effects to be aliased with two-factor interactions. This is typically the lowest resolution desired for a fraction. It is not hard to see that a fraction of resolution also has resolution , etc., so one usually speaks of the maximum resolution of a fraction.
The number in the definition of resolution is usually understood to be a positive integer, but one may consider the effect of the grand mean to be the (unique) effect with no factors (i.e., with ). This effect sometimes appears in analysis of variance tables. It has one degree of freedom, and is represented by a single vector, a column of 1's. With this understanding, an effect is
preserved in a fraction if it is unaliased with the grand mean, and
completely lost in a fraction if it is completely aliased with the grand mean.
A fraction then has resolution if all main effects are preserved in the fraction. If it has resolution then two-factor interactions are also preserved.
Computation
The definitions above require some computations with vectors, illustrated in the examples that follow. For certain fractional designs (the regular ones), a simple algebraic technique can be used that bypasses these procedures and gives a simple way to determine resolution. This is discussed below.
Examples
The 2 × 3 experiment
The fraction {11, 12, 13} of this experiment was described above along with its restricted vectors. It is repeated here along with the complementary fraction {21, 22, 23}:
In both fractions, the effect is completely lost (the column is constant) while the and interaction effects are preserved (each 3 × 1 column is a contrast vector as its components sum to 0). In addition, the and interaction effects are completely aliased in each fraction: In the first fraction, the vectors for are linear combinations of those for , viz.,
and
;
in the reverse direction, the vectors for can be written similarly in terms of those representing . The argument in the second fraction is analogous.
These fractions have maximum resolution 1. The fact that the main effect of is lost makes both of these fractions undesirable in practice. It turns out that in a 2 × 3 experiment (or in any a × b experiment in which a and b are relatively prime) there is no fraction that preserves both main effects -- that is, no fraction has resolution 2.
The 2 × 2 × 2 (or 2³) experiment
This is a "two-level" experiment with factors and . In such experiments the factor levels are often denoted by 0 and 1, for reasons explained below. A treatment combination is then denoted by an ordered triple such as 101 (more formally, (1, 0, 1), denoting the cell in which and are at level "1" and is at level "0"). The following table lists the eight cells of the full 2 × 2 × 2 factorial experiment, along with a contrast vector representing each effect, including a three-factor interaction:
Suppose that only the fraction consisting of the cells 000, 011, 101, and 110 is observed. The original contrast vectors, when restricted to these cells, are now 4 × 1, and can be seen by looking at just those four rows of the table. (Sorting the table on will bring these rows together and make the restricted contrast vectors easier to see. Sorting twice puts them at the top.) The following can be observed concerning these restricted vectors:
The column consists just of the constant 1 repeated four times.
The other columns are contrast vectors, having two 1's and two −1s.
The columns for and are equal. The same holds for and , and for and .
All other pairs of columns are orthogonal. For example, the column for is orthogonal to that for , for , for , and for , as one can see by computing dot products.
Thus
the interaction is completely lost in the fraction;
the other effects are preserved in the fraction;
the effects and are completely aliased with each other, as are and , and and .
all other pairs of effects are unaliased. For example, is unaliased with both and and with the and interactions.
Now suppose instead that the complementary fraction {001,010,100,111} is observed. The same effects as before are lost or preserved, and the same pairs of effects as before are mutually unaliased. Moreover, and are still aliased in this fraction since the and vectors are negatives of each other, and similarly for and and for and . Both of these fractions thus have maximum resolution 3.
Aliasing in regular fractions
The two half-fractions of a factorial experiment described above are of a special kind: Each is the solution set of a linear equation using modular arithmetic. More exactly:
The fraction is the solution set of the equation . For example, is a solution because .
Similarly, the fraction is the solution set to
Such fractions are said to be regular. This idea applies to fractions of "classical" designs, that is, (or "symmetric") factorial designs in which the number of levels, , of each of the factors is a prime or the power of a prime.
A fractional factorial design is regular if it is the solution set of a system of one or more equations of the form
where the equation is modulo if is prime, and is in the finite field if is a power of a prime. Such equations are called defining equations of the fraction. When the defining equation or equations are homogeneous, the fraction is said to be principal.
One defining equation yields a fraction of size , two independent equations a fraction of size and so on. Such fractions are generally denoted as designs. The half-fractions described above are designs. The notation often includes the resolution as a subscript, in Roman numerals; the above fractions are thus designs.
Associated to each expression is another, namely , which rewrites the coefficients as exponents. Such expressions are called "words", a term borrowed from group theory. (In a particular example where is a specific number, the letters are used, rather than .) These words can be multiplied and raised to powers, where the word acts as a multiplicative identity, and they thus form an abelian group , known as the effects group. When is prime, one has for every element (word) ; something similar holds in the prime-power case.
In factorial experiments, each element of represents a main effect or interaction. In experiments with , each one-letter word represents the main effect of that factor, while longer words represent components of interaction. An example below illustrates this with .
To each defining expression (the left-hand side of a defining equation) corresponds a defining word. The defining words generate a subgroup of that is variously called the alias subgroup, the defining contrast subgroup, or simply the defining subgroup of the fraction. Each element of is a defining word since it corresponds to a defining equation, as one can show. The effects represented by the defining words are completely lost in the fraction while all other effects are preserved. If , say, then the equation
is called the defining relation of the fraction. This relation is used to determine the aliasing structure of the fraction: If a given effect is represented by the word , then its aliases are computed by multiplying the defining relation by , viz.,
where the products are then simplified. This relation indicates complete (not partial) aliasing, and W is unaliased with all other effects listed in .
Example 1
In either of the fractions described above, the defining word is , since the exponents on these letters are the coefficients of . The effect is completely lost in the fraction, and the defining subgroup is simply , since squaring does not generate new elements . The defining relation is thus
,
and multiplying both sides by gives ; which simplifies to
the alias relation seen earlier. Similarly, and . Note that multiplying both sides of the defining relation by and does not give any new alias relations.
For comparison, the fraction with defining equation has the defining word (i.e., ). The effect is completely lost, and the defining relation is . Multiplying this by , by , and by gives the alias relations , , and among the six remaining effects. This fraction only has resolution 2 since all effects (except ) are preserved but two main effects are aliased. Finally, solving the defining equation yields the fraction {000, 001, 110, 111}. One may verify all of this by sorting the table above on column .
The use of arithmetic modulo 2 explains why the factor levels in such designs are labeled 0 and 1.
Example 2
In a 3-level design, factor levels are denoted 0, 1 and 2, and arithmetic is modulo 3. If there are four factors, say and , the effects group will have the relations
From these it follows, for example, that and .
A defining equation such as would produce a regular 1/3-fraction of the 81 (= ) treatment combinations, and the corresponding defining word would be . Since its powers are
and ,
the defining subgroup would be , and so the fraction would have defining relation
Multiplying by , for example, yields the aliases
For reasons explained elsewhere, though, all powers of a defining word represent the same effect, and the convention is to choose that power whose leading exponent is 1. Squaring the latter two expressions does the trick and gives the alias relations
Twelve other sets of three aliased effects are given by Wu and Hamada. Examining all of these reveals that, like , main effects are unaliased with each other and with two-factor effects, although some two-factor effects are aliased with each other. This means that this fraction has maximum resolution 4, and so is of type .
The effect is one of 4 components of the interaction, while is one of 8 components of the interaction. In a 3-level design, each component of interaction carries 2 degrees of freedom.
Example 3
A design ( of a design) may be created by solving two equations in 5 unknowns, say
modulo 2. The fraction has eight treatment combinations, such as 10000, 00110 and 11111, and is displayed in the article on fractional factorial designs. Here the coefficients in the two defining equations give defining words and . Setting and multiplying through by gives the alias relation . The second defining word similarly gives . The article uses these two aliases to describe an alternate method of construction of the fraction.
The defining subgroup has one more element, namely the product , making use of the fact that . The extra defining word is known as the generalized interaction of and , and corresponds to the equation , which is also satisfied by the fraction. With this word included, the full defining relation is
(these are the four elements of the defining subgroup), from which all the alias relations of this fraction can be derived – for example, multiplying through by yields
.
Continuing this process yields six more alias sets, each containing four effects. An examination of these sets reveals that main effects are not aliased with each other, but are aliased with two-factor interactions. This means that this fraction has maximum resolution 3. A quicker way to determine the resolution of a regular fraction is given below.
It is notable that the alias relations of the fraction depend only on the left-hand side of the defining equations, not on their constant terms. For this reason, some authors will restrict attention to principal fractions "without loss of generality", although the reduction to the principal case often requires verification.
Determining the resolution of a regular fraction
The length of a word in the effects group is defined to be the number of letters in its name, not counting repetition. For example, the length of the word is 3.
Using this result, one immediately gets the resolution of the preceding examples without computing alias relations:
In the fraction with defining word , the maximum resolution is 3 (the length of that word), while the fraction with defining word has maximum resolution 2.
The defining words of the fraction were and , both of length 4, so that the fraction has maximum resolution 4, as indicated.
In the fraction with defining words and , the maximum resolution is 3, which is the shortest "wordlength".
One could also construct a fraction from the defining words and , but the defining subgroup will also include , their product, and so the fraction will only have resolution 2 (the length of ). This is true starting with any two words of length 4. Thus resolution 3 is the best one can hope for in a fraction of type .
As these examples indicate, one must consider all the elements of the defining subgroup in applying the theorem above. This theorem is often taken to be a definition of resolution, but the Box-Hunter definition given earlier applies to arbitrary fractional designs and so is more general.
Aliasing in general fractions
Nonregular fractions are common, and have certain advantages. For example, they are not restricted to having size a power of , where is a prime or prime power. While some methods have been developed to deal with aliasing in particular nonregular designs, no overall algebraic scheme has emerged.
There is a universal combinatorial approach, however, going back to Rao. If the treatment combinations of the fraction are written as rows of a table, that table is an orthogonal array. These rows are often referred to as "runs". The columns will correspond to the factors, and the entries of the table will simply be the symbols used for factor levels, and need not be numbers. The number of levels need not be prime or prime-powered, and they may vary from factor to factor, so that the table may be a mixed-level array. In this section fractional designs are allowed to be mixed-level unless explicitly restricted.
A key parameter of an orthogonal array is its strength, the definition of which is given in the article on orthogonal arrays. One may thus refer to the strength of a fractional design. Two important facts flow immediately from its definition:
If an array (or fraction) has strength then it also has strength for every . The array's maximum strength is of particular importance.
In a fixed-level array, all factors having levels, the number of runs is a multiple of , where is the strength. Here need not be a prime or prime power.
To state the next result, it is convenient to enumerate the factors of the experiment by 1 through , and to let each nonempty subset of correspond to a main effect or interaction in the following way: corresponds to the main effect of factor
, corresponds to the interaction of factors and , and so on.
Example: Consider a fractional factorial design with factors and maximum strength . Then:
All effects up to three-factor interactions are preserved in the fraction.
Main effects are unaliased with each other and with two-factor interactions.
Two-factor interactions are unaliased with each other if they share a factor. For example, the and interactions are unaliased, but the and interactions may be at least partly aliased as the set contains 4 elements but the strength of the fraction is only 3.
The Fundamental Theorem has a number of important consequences. In particular, it follows almost immediately that if a fraction has strength then it has resolution . With additional assumptions, a stronger conclusion is possible:
This result replaces the group-theoretic condition (minimum wordlength) in regular fractions with a combinatorial condition (maximum strength) in arbitrary ones.
Example. An important class of nonregular two-level designs are Plackett-Burman designs. As with all fractions constructed from Hadamard matrices, they have strength 2, and therefore resolution 3. The smallest such design has 11 factors and 12 runs (treatment combinations), and is displayed in the article on such designs. Since 2 is its maximum strength, 3 is its maximum resolution. Some detail about its aliasing pattern is given in the next section.
Partial aliasing
In regular fractions there is no partial aliasing: Each effect is either preserved or completely lost, and effects are either unaliased or completely aliased. The same holds in regular experiments with if one considers only main effects and components of interaction. However, a limited form of partial aliasing occurs in the latter. For example, in the design described above the overall interaction is partly lost since its component is completely lost in the fraction while its other components (such as ) are preserved. Similarly, the main effect of is partly aliased with the interaction since is completely aliased with its component and unaliased with the others.
In contrast, partial aliasing is uncontrolled and pervasive in nonregular fractions. In the 12-run Plackett-Burman design described in the previous section, for example, with factors labeled through , the only complete aliasing is between "complementary effects" such as and or and . Here the main effect of factor is unaliased with the other main effects and with the interaction, but it is partly aliased with 45 of the 55 two-factor interactions, 120 of the 165 three-factor interactions, and 150 of the 330 four-factor interactions. This phenomenon is generally described as complex aliasing. Similarly, 924 effects are preserved in the fraction, 1122 effects are partly lost, and only one (the top-level interaction ) is completely lost.
Analysis of variance (ANOVA)
Wu and Hamada analyze a data set collected on the fractional design described above. Significance testing in the analysis of variance (ANOVA) requires that the error sum of squares and the degrees of freedom for error be nonzero. In order to insure this, two design decisions have been made:
Interactions of three or four factors have been assumed absent. This decision is consistent with the effect hierarchy principle.
Replication (inclusion of repeated observations) is necessary. In this case, three observations were made on each of the 27 treatment combinations in the fraction, for a total of 81 observations.
The accompanying table shows just two columns of an ANOVA table for this experiment. Only main effects and components of two-factor interactions are listed, including three pairs of aliases. Aliasing between some two-factor interactions is expected, since the maximum resolution of this design is 4.
This experiment studied two response variables. In both cases, some aliased interactions were statistically significant. This poses a challenge of interpretation, since without more information or further assumptions it is impossible to determine which interaction is responsible for significance. In some instances there may be a theoretical basis to make this determination.
This example shows one advantage of fractional designs. The full factorial experiment has 81 treatment combinations, but taking one observation on each of these would leave no degrees of freedom for error. The fractional design also uses 81 observations, but on just 27 treatment combinations, in such a way that one can make inferences on main effects and on (most) two-factor interactions. This may be sufficient for practical purposes.
History
The first statistical use of the term "aliasing" in print is the 1945 paper by Finney, which dealt with regular fractions with 2 or 3 levels. The term was imported into signal processing theory a few years later, possibly influenced by its use in factorial experiments; the history of that usage is described in the article on aliasing in signal processing.
The 1961 paper in which Box and Hunter introduced the concept of "resolution" dealt with regular two-level designs, but their initial definition makes no reference to lengths of defining words and so can be understood rather generally. Rao actually makes implicit use of resolution in his 1947 paper introducing orthogonal arrays, reflected in an important parameter inequality that he develops. He distinguishes effects in full and fractional designs by using symbols and (corresponding to and ), but makes no mention of aliasing.
The term confounded is often used as a synonym for aliased, and so one must read the literature carefully. The former term "is generally reserved for the indistinguishability of a treatment contrast and a block contrast", that is, for confounding with blocks. Kempthorne has shown how confounding with blocks in a -factor experiment may be viewed as aliasing in a fractional design with factors, but it is unclear whether one can do the reverse.
See also
The article on fractional factorial designs discusses examples in two-level experiments.
Notes
Citations
References
Design of experiments
Statistical process control | Aliasing (factorial experiments) | [
"Engineering"
] | 5,499 | [
"Statistical process control",
"Engineering statistics"
] |
73,359,253 | https://en.wikipedia.org/wiki/RS%20Cancri | RS Cancri, also known as HR 3639 and HD 78712, is a star about 490 light years from the Earth in the constellation Cancer. It is a semiregular variable star, ranging in brightness from magnitude 5.4 to 7.3 over a period of about 229 days. During the time intervals when it is brighter than magnitude 6, it may be faintly visible to the naked eye of an observer far from city lights.
The variability of RS Cancri was discovered by Edward Pickering based upon 15 observations made in 1892 and 1898. S. Seliwanow derived a period of 129.5 days for the star, in 1923. In 2005, Saul Adelman and John Dennis found that the star showed two periods well determined by their data, and days, as well as a poorly-determined third period of about 500 days.
RS Cancri is an S-type star, on the asymptotic giant branch. Its spectrum shows technetium, implying the star has undegone the third dredge-up. RS Cancri has a stellar wind, and is losing mass at a rate of solar masses per year.
RS Cancri has a circumstellar shell. It is a good target for studies of such a shell, because its rather high galactic latitude (+42 degrees) means that it is cleanly separated from the interstellar dust and gas seen along most lines of sight through the galactic plane. Dust within the shell produces far-infrared continuum emission that was resolved by IRAS. Both atomic and molecular gas within the shell are also measurably extended, and have been mapped.
The extensive molecular envelope surrounding RS Cancri was first detected in 1977, by Kwok-Yung (Fred) Lo and Kenneth Bechis, who used the 36 foot radio telescope on Kitt Peak to detect the J=1-0 line of carbon monoxide (CO). Years later, when observations of spectral lines could be made with more sensitive equipment, it was noticed that the shapes of the spectral lines suggested that RS Cancri has two distinct stellar wind components, expanding into space at different speeds. Interferometric observations have shown that the two winds consist of a ~2 km/sec wind arising from an equatorial disk within the envelope, and an ~8 km/sec bipolar wind. In subsequent decades, additional molecules such as SiO, SO, SO2, H2O HCN and PN have been detected.
References
Cancer (constellation)
Cancri, RS
078712
045058
3639
Semiregular variable stars
S-type stars
M-type giants | RS Cancri | [
"Astronomy"
] | 541 | [
"Cancer (constellation)",
"Constellations"
] |
73,360,935 | https://en.wikipedia.org/wiki/Learn%20to%20Code | "Learn to Code" was a slogan and a series of public influence campaigns during the 2010s that encouraged the development of computer programming skills in an economy increasingly centered on information technology. The campaigns led to endorsements from politicians, the inclusion of programming in state school curricula, and the proliferation of coding bootcamps. Learning to code has a long history in the U.S., with moments of enthusiasm and anxiety about computational literacy and the best methods to learn programming skills. A backlash erupted in 2019 in the form of online harassment of laid-off American journalists.
Context
The notion of code literacy – that is, computer programming as an element of primary or liberal education — has been traced to Alan Perlis's 1962 essay "The Computer in the University." Perlis called for a course in the first two years of college in which students would write or observe a large number of programs. John Kemeny and Thomas Kurtz created the BASIC programming language in support of this goal, and the Logo language was introduced as a tool for early-childhood education. Follow-up research found little evidence of the predicted cognitive benefits of programming education, and the rise of the software industry and graphical user interfaces caused educational focus to shift in the 1990s toward end-user skills. Computers were also expensive, limiting the integration of coding skills into the school curriculum. By 1995, there were approximately three computers for every 30 children in American schools. Despite these factors, research and advocacy for programming literacy continued.
In the 2010s, valuations of information technology companies grew significantly. In March 2010, the top ten most valuable US companies included Microsoft and Apple at No. 2 and No. 3 and Google at No. 9. The following year Apple displaced ExxonMobil as the highest-valued US company. Technology venture capitalist Marc Andreessen remarked that "software is eating the world" and predicted that software would assume a central place in the US economy. Noting that unemployment remained high in the wake of the 2007–2008 financial crisis, he proposed greater emphasis on education in all aspects of the software industry to avoid further unemployment caused by software-driven disruption. By June 2015 all three technology companies were at the top of the value ranking and Facebook at No. 12 had surpassed Walmart. By March 2019 Amazon had joined Apple, Microsoft and Google (Alphabet Inc.) in the top four, Facebook stood at No. 6, and payment technology company Visa Inc. was at No. 8.
Coding instruction was thoroughly transformed by commercialization and Internet-based teaching practices in the 21st century. Collectively, learning to code has taken on the trappings of a popular movement, with utopian ideals, charismatic leaders, capitalist narratives, and shared identities.
Codecademy and Code.org
Zach Sims and Ryan Bubinski launched Codecademy in August 2011 with a mission to offer "crash courses" in computer programming to a broad audience. It received initial funding from several technology venture capital firms including Union Square Ventures, O'Reilly Media's AlphaTech Ventures, Y Combinator and Chris Dixon's Founder Collective. The following January Codecademy launched a viral marketing campaign called Code Year that urged people to make "learn to code" one of their New Year's resolutions. The launch of the campaign's web site, which featured endorsements from Codecademy's investors, was promoted on social media by New York mayor Michael Bloomberg and Washington Post reporter Ezra Klein, among others. Media outlets publicizing the launch included CNN, CNN Money, The New Yorker, Slate and Fast Company (with an article written by Sims).
Some commentators responded skeptically to Code Year. Personal computing journalist Matthew Murray countered that programming well enough to be professionally adept typically required years of practice and expressed reservations about the "commoditizing and corruption" of a difficult career. More prominently, Jeff Atwood, co-founder of the programming question-and-answer site Stack Overflow, argued that the supply of coding talent should be balanced with its practical demand, which was constrained by the applicability of programming to problems and the disadvantages of writing more code than necessary. Former software developer Ciara Byrne was similarly critical in late 2013. Code Year was nonetheless successful at introducing the advocacy of code literacy into public discourse in the ensuing years. In one instance, NBC's Today show reported approvingly in November 2013 on a New York technology entrepreneur who gave a homeless man, Leo Grand, a laptop computer and JavaScript coding lessons.
January 2013 saw the founding of a permanent code literacy advocacy group, Code.org. The organization debuted with an advertisement featuring Bill Gates, Mark Zuckerberg, Jack Dorsey and other technology businesspeople, as well as non-technology personalities like musician will.i.am and athlete Chris Bosh. Code.org launched the "Hour of Code" campaign in December, with endorsements from Barack Obama, actor/businessman Ashton Kutcher and singer Shakira, which featured workshops at the Apple and Microsoft campuses and asked school teachers to devote an hour of class time to programming education. The group did not disclose its initial funding, but in 2016 it raised a total of $23 million for teacher training and policy advocacy from Facebook, Mark Zuckerberg, his wife Priscilla Chan, Microsoft, Google and Infosys.
In 2014 other programming education startups joined Codecademy for another Year of Code campaign that targeted the United Kingdom. Saul Klein, an early investor in Codecademy and Seedcamp, another participating startup, was on the campaign's board of directors. The BBC, a partner in the campaign, promoted it without consistently disclosing its involvement. Stirling University social scientist Ben Williamson studied the development of "learning to code" advocacy networks in the UK, describing them as "not a coherent and stable network but a messy hybrid of intentions, ambitions, and interests." He identified Code Club as an early manifestation of the movement, founded in April 2012 and supported by Microsoft, Google and the Department for Education.
Policy impact
A December 2014 announcement by the Obama administration showed the results of code literacy activism. It included commitments by 60 school districts, philanthropic donors, the National Science Foundation (NSF) and the College Board to improve computer science education in schools. The administration announced more direct federal support in March 2015 through the TechHire initiative. A joint effort among federal, state and local governments and the private sector, TechHire pledged $100 million in federal grants for non-degree programs to train people in software development. Codecademy and bootcamp programs at Flatiron School, Galvanize and Hack Reactor were noted as examples of the accelerated training approach that would be supported. In 2016 Obama requested $4.2 billion in funding for computer science education. This was not approved, but more limited funding was directed through the NSF, the Department of Education and Americorps toward teacher training and education research. At the state level, Arkansas governor Asa Hutchinson spent $5 million to promote coding education in public schools and established an online training system for rural schools.
Policy results were also achieved in other countries. The UK Department for Education updated the standard school curriculum in 2013 to add computing as a "fourth science," and the government committed £84 million to computer science education improvements in 2017. The Swedish government endorsed a national information technology education policy in 2016, with coding requirements, to be funded and implemented at the local level. When asked about coding education for children in a 2015 "question time" session, Australian prime minister Tony Abbott dismissed the idea, even though his government had already committed A$3.5 million to coding as an optional part of the school curriculum. The succeeding government of Malcolm Turnbull amended Abbott's national curriculum to include coding education from year 3 onward, and approved A$7 million for online training of teachers.
Training outcomes
The retraining of coal miners in central Appalachia became a testing ground for "learn to code" efforts. When Bloomberg was asked in April 2014 about phasing out coal power due to clean energy commitments, he agreed that it was necessary but cautioned that technology jobs were oversold as a solution to unemployment. In 2016 several optimistic reports appeared about Bit Source, a web development startup in Pikeville, Kentucky staffed with retrained coal miners. Subsequent reports suggested a more mixed record, with miners completing the program of one Appalachian training academy but not receiving their certificates or finding any jobs. Despite such concerns, Democratic presidential candidate Joe Biden endorsed learning to code as a way forward for miners and other blue-collar workers during a campaign speech at Derry, New Hampshire on December 30, 2019: "Anybody who can go down 300 to 3,000 feet in a mine, sure in hell can learn to program as well, but we don't think of it that way. Even my liberal friends don't." Washington Post reporter Dave Weigel, who broke the remark on Twitter, commented that such exhortations to "just transition" had harmed Hillary Clinton's campaign in 2016, and Democratic congressional candidate Brianna Wu called it "tone-deaf and unhelpful."
A series of coding school closures in 2017 prompted a reconsideration of the model; a Bloomberg report found that several large San Francisco Bay area technology companies were unsatisfied with coding schools' results and did not pursue their students for employment. A broader survey in 2018 by Stack Overflow found that nearly half of bootcamp graduates were current software developers building their skills. Among the remaining 54.5%, 16.3% found a job immediately while 20% took three months or longer.
Harassment of journalists
In January 2019 Huffington Post, Gannett, BuzzFeed and Verizon Media announced layoffs of journalists. As the journalists confirmed their involvement on social media, strangers responded with a torrent of mockery and hate speech mixed with suggestions to learn to code. The harassment was found to be coordinated on 4chan, a lightly moderated and anonymous message board that had previously coordinated the GamerGate campaign. Twitter responded by blocking accounts involved in the harassment, drawing derision from Fox News personality Tucker Carlson and suggestive endorsements of the harassment from right-wing figures Ben Shapiro, Donald Trump Jr. and David Duke.
Aftermath
Technology companies continued to grow in value through 2020 and 2021. The COVID-19 pandemic created demand for online commerce and work arrangements while hampering other sectors, and investment capital flooded into the sector. A new campaign fronted by Ivanka Trump and Apple CEO Tim Cook advised workers laid off in the pandemic to "find something new" by pursuing education in various fields, including web development. At the end of March 2021, the five most valuable US companies were information technology companies, four had valuations exceeding $1 trillion, and Apple had a valuation exceeding $2 trillion. The reopening of workplaces and the tightening of credit policy by the Federal Reserve counteracted both trends that had driven this boom. During 2022 and 2023 technology companies announced layoffs that cast doubt on computer programming as a sure career bet, while industry insiders began to talk up the prospect of eliminating human programmers with low-code/no-code tools and generative artificial intelligence.
See also
Atari Democrat
Computer Lib/Dream Machines
Job obsolescence
New Math
One Laptop per Child
Technological unemployment
References
Further reading
External links
Computer science education
Social movements | Learn to Code | [
"Technology"
] | 2,306 | [
"Computer science education",
"Computer science"
] |
73,361,588 | https://en.wikipedia.org/wiki/Net-zero%20emissions | Global net-zero emissions describe the state where emissions of greenhouse gases due to human activities and removals of these gases are in balance over a given period. It is often called simply net zero. In some cases, emissions refers to emissions of all greenhouse gases, and in others it refers only to emissions of carbon dioxide (). To reach net zero targets requires actions to reduce emissions. One example would be by shifting from fossil fuel energy to sustainable energy sources. Organizations often offset their residual emissions by buying carbon credits.
People often use the terms net-zero emissions, carbon neutrality, and climate neutrality with the same meaning. However, in some cases, these terms have different meanings from each other. For example, some standards for carbon neutral certification allow a lot of carbon offsetting. But net zero standards require reducing emissions to more than 90% and then only offsetting the remaining 10% or less to fall in line with 1.5 °C targets.
In the last few years, net zero has become the main framework for climate action. Many countries and organizations are setting net zero targets. As of November 2023, around 145 countries had announced or are considering net zero targets, covering close to 90% of global emissions. They include some countries that were resistant to climate action in previous decades. Country-level net zero targets now cover 92% of global GDP, 88% of emissions, and 89% of the world population. 65% of the largest 2,000 publicly traded companies by annual revenue have net zero targets. Among Fortune 500 companies, the percentage is 63%. Company targets can result from both voluntary action and government regulation.
Net zero claims vary enormously in how credible they are, but most have low credibility despite the increasing number of commitments and targets. While 61% of global carbon dioxide emissions are covered by some sort of net zero target, credible targets cover only 7% of emissions. This low credibility reflects a lack of binding regulation. It is also due to the need for continued innovation and investment to make decarbonization possible.
To date, 27 countries have enacted domestic net zero legislation. These are laws that legislatures have passed that contain net zero targets or equivalent. There is currently no national regulation in place that legally requires companies based in that country to achieve net zero. Several countries, for example Switzerland, are developing such legislation.
History and scientific justification
The idea of net zero came out of research in the late 2000s into how the atmosphere, oceans and carbon cycle were reacting to CO2 emissions. This research found that global warming will only stop if CO2 emissions are reduced to net zero. Net zero was basic to the goals of the Paris Agreement. This stated that the world must "achieve a balance between anthropogenic emissions by sources and removals by sinks of greenhouse gases in the second half of this century". The term "net zero" gained popularity after the Intergovernmental Panel on Climate Change published its Special Report on Global Warming of 1.5 °C (SR15) in 2018, this report stated that "Reaching and sustaining net zero global anthropogenic [human-caused] CO2 emissions and declining net non-CO2 radiative forcing would halt anthropogenic global warming on multi-decadal timescales (high confidence)."
The idea of net-zero emissions is often confused with "stabilization of greenhouse gas concentrations in the atmosphere". This is a term that dates from the 1992 Rio Convention. The two concepts are not the same. This is because the carbon cycle continuously sequesters or absorbs a small percentage of cumulative historical human-caused CO2 emissions into vegetation and the ocean. This happens even after current CO2 emissions are reduced to zero. If the concentration of CO2 in the atmosphere were kept constant, some CO2 emissions could continue. However global average surface temperatures would continue to increase for many centuries due to the gradual adjustment of deep ocean temperatures. If CO2 emissions that result directly from human activities are reduced to net zero, the concentration of CO2 in the atmosphere would decline. This would be at a rate just fast enough to compensate for this deep ocean adjustment. The result would be approximately constant global average surface temperatures over decades or centuries.
Types of greenhouse gas
It will be quicker to reach net-zero emissions for CO2 alone rather than CO2 plus other greenhouse gases like methane, nitrous oxide and fluorinated gases. The net-zero target date for non-CO2 emissions is later partly because modellers assume that some of these emissions such as methane from farming are harder to phase out. Emissions of short-lived gases such as methane do not accumulate in the climate system in the same way that CO2 does. Therefore there is no need to reduce them to zero to halt global warming. This is because reductions in emissions of short-lived gases cause an immediate decline in the resulting radiative forcing. Radiative forcing is the change in the Earth's energy balance that they cause. However, these potent but short-lived gases will drive temperatures higher in the short term. This could possibly push the rise in temperature past the 1.5 °C threshold much earlier. A comprehensive net-zero emissions target would include all greenhouse gases. This would ensure that the world would also urgently reduce non-CO2 gases.
Some targets aim to reach net-zero emissions only for carbon dioxide. Others aim to reach net-zero emissions of all greenhouse gases. Robust net zero standards state that all greenhouse gases should be covered by a given actor's targets.
Some authors say that carbon neutrality strategies focus only on carbon dioxide, but net zero includes all greenhouse gases. However some publications, such as the national strategy of France, use the term "carbon neutral" to mean net reductions of all greenhouse gases. The United States has pledged to achieve "net zero" emissions by 2050. As of March 2021 it had not specified which greenhouse gases will be included in its target.
Terminology
Countries, local governments, corporations, and financial institutions may all announce pledges for achieving to reach net-zero emissions.
In climate change discussions, the terms net zero, carbon neutrality, and climate neutrality are often used as if they mean the same thing. In some contexts, however, they have different meanings from each other. The sections below explain this. People often use these terms without rigorous standard definitions.
Approaches
A given actor may plan to achieve net-zero emissions through a combination of approaches. These would include (1) actions to reduce their own emissions, (2) actions to reduce the emissions of others (third parties), and (3) actions to directly remove carbon dioxide from the atmosphere (carbon sinks).
Reducing emissions
Robust net zero standards require actors to reduce their own emissions as much as possible following science-based pathways. They must then balance their residual emissions using removals and offsets. This typically involves shifting from fossil fuels to sustainable energy sources. Residual emissions are emissions that are not practical to reduce for technological reasons.
Experts and net zero frameworks disagree over the exact percentage of residual emissions that may be allowed. Most guidance suggests this should be limited to a small fraction of total emissions. Sector-specific and geographical factors would determine how much. The Science Based Targets initiative says that residual emissions across most sectors should fall to below 10% of an organization's baseline emissions by 2050. It should be even lower for some sectors with competitive alternatives like the power sector. Sectors such as heavy manufacturing where it is harder to mitigate emissions will probably have a higher percentage of residual emissions by 2050.
The ISO and British Standards Institution (BSI) publish "carbon neutrality" standards that have higher tolerance for residual emissions than "net zero" standards. For example, BSI PAS 2060 is a British standard for measuring carbon neutrality. According to these standards, carbon neutrality is a short-term target, and net zero is a longer-term target.
Carbon removals and offsets
To balance residual emissions, actors may take direct action to remove carbon dioxide from the atmosphere and sequester it. Alternatively or in addition they can buy carbon credits that "offset" emissions. Carbon credits can be used to fund carbon removal projects such as reforestation.
Strong standards such as the ISO and BSI "net zero" standards only allow removal-based offsets that have the same permanence as the greenhouse gases that they balance. The term for this concept is "like for like" removals. Permanence means that removals must store greenhouse gases for the same period as the lifetime of the GHG emissions they balance. For example, methane has a lifetime of around 12 years in the atmosphere. Carbon dioxide lasts between 300 and 1,000 years. Accordingly, removals that balance carbon dioxide must last much longer than removals that balance methane.
Carbon credits can also fund initiatives that aim to avoid emissions. One example would be energy efficiency retrofits or renewable energy projects. Avoided emissions offsets result from actions that reduce emissions relative to a baseline or status quo. But they do not remove emissions from the atmosphere. Weak standards such as ISO and BSI "carbon neutrality" standards allow organizations to use avoided-emissions carbon credits. They do not specify how permanent or durable a credit must be.
Carbon offsetting has been criticized on several fronts. One important concern is that offsets may delay active emissions reductions. In a 2007 report from the Transnational Institute, Kevin Smith likened carbon offsets to medieval indulgences. He said they allowed people to pay "offset companies to absolve them of their carbon sins." He said this permits a "business as usual" attitude that stifles required major changes. Many people have criticized offsets for playing a part in greenwashing. This argument appeared in a 2021 watchdog ruling against Shell.
Loose regulation of claims by carbon offsetting schemes combined with the difficulties in calculating greenhouse gas sequestration and emissions reductions has also given rise to criticism. This argument is that this can result in schemes that do not adequately offset emissions in reality. There have been moves to create better regulation. The United Nations has operated a certification process for carbon offsets since 2001. This is called the Clean Development Mechanism. It aims to stimulate "sustainable development and emission reductions, while giving industrialized countries some flexibility in how they meet their emission reduction limitation targets." The UK Government's Climate Change Committee says reported emissions reductions or removals may have happened anyway or. not last into the future. This is despite an improvement in standards globally and in the UK.
There has also been criticisms of non-native and monocultural forest plantations as carbon offsets. This is because of their "limited—and at times negative—effects on native biodiversity" and other ecosystem services.
Most of the carbon credits on the voluntary market today do not meet UN, UNFCCC, ISO or SBTi standards for permanent carbon dioxide removals. So significant investment in carbon capture and permanent geological storage will probably be necessary to achieve net-zero targets by mid-century.
Implementation
Since 2015, there has been significant growth in the number of actors pledging net-zero emissions. Many standards have emerged that interpret the net zero concept and aim to measure progress towards net zero targets. Some of these standards are more robust than others. Some people have criticized weak standards for facilitating greenwashing. The UN, UNFCCC, International Organization for Standardization (ISO), and the Science Based Targets initiative (SBTi) promote more robust standards.
The "United Nations High-Level Expert Group" on the net-zero emissions commitments of non-state entities has made several recommendations for non-state actors. Non-state actors include cities, regional governments, financial institutions, and corporations. One of these is not financing new fossil fuel development. Another is supporting strong climate policy. And another is ensuring that business activities and investments do not contribute to deforestation.
65% of the largest 2,000 publicly traded companies by annual revenue have net zero targets. Among Fortune 500 companies the percentage is 63%. Company targets can result from both voluntary action and government regulation.
Scopes of emissions sources
The Greenhouse Gas Protocol is a group of standards that are the most common in GHG accounting. These standards reflect a number of accounting principles. They include relevance, completeness, consistency, transparency, and accuracy. The standards divide emissions into three scopes:
Scope 1 covers all direct GHG emissions within a corporate boundary (owned or controlled by a company). It includes fuel burned by the company, use of company vehicles, and fugitive emissions.
Scope 2 covers indirect GHG emissions from consumption of purchased electricity, heat, cooling or steam. As of 2010, at least one third of global GHG emissions are Scope 2.
Scope 3 emission sources include emissions from suppliers and product users (also known as the "value chain"). Transportation of goods, and other indirect emissions are also part of this scope. Scope 3 emissions were estimated to represent 75% of all emissions reported to the Carbon Disclosure Project, though that percentage varies widely amongst business sectors.
Corporate net zero targets vary in how widely they cover emissions related to the company's activities. This can greatly affect the volume of emissions that are counted. Some oil companies, for instance, claim that their operations (Scopes 1 and 2) produce net-zero emissions. These claims do not cover the emissions produced when the oil is burned by its customers, which are 70 - 90% of oil-related emissions. This is because they count as Scope 3 emissions.
Robust net zero standards require Scope 3 emissions to be counted, but "carbon neutrality" standards do not.
Timeframe
To achieve net zero, actors are encouraged to set net zero targets for 2050 or earlier. Long-term net zero targets should be supplemented by interim targets for every one to five years. The UN, UNFCCC, ISO, and SBTi all say that organizations should prioritize early, front-loaded emissions reduction. They say they should aim to halve emissions by 2030. Specific emissions reduction targets and pathways may look different for different sectors. Some may be able to decarbonize more quickly and easily than others.
Many companies often claim a commitment to reach net-zero emissions by the year 2050. These promises are often made at the corporate level. Both governments and international agencies encourage businesses to contribute to a national, or international, net zero pledge. The International Energy Agency says that global investment in low carbon substitutes for fossil fuels needs to reach US$4 trillion annually by 2030 for the world to get to net zero by 2050.
Some analyses have raised concerns that net zero cannot be achieved worldwide by 2050.
On average, approximately 29% of companies in EU member states have formulated a respective target to achieve net zero or have already reached this goal. However, these numbers can vary significantly across different industries, countries, and firm sizes. External pressures, such as companies' exposure to risks associated with climate change and its perception as a problem, can influence a company's ambition to adopt specific targets and strategies.
Comprehensive accounting
The guidance from standards institutions says that organizations should choose a base year to measure emissions reductions against. This should be representative of their typical greenhouse gas profile. They should explain the choice of baseline and how they will account for changes in conditions since the baseline. Financial organizations should also include emissions within their portfolio. This should include all organizations they have financed, invested in, or insured. Countries and regions should include both territorial emissions released within their boundaries and consumption emissions related to products and services imported and consumed within their boundaries.
Cities and countries pose a challenge when it comes to calculating emissions. This is because the production of products and services within their boundaries might be linked to either internal consumption or exports. At the same time the population also consumes imported products and services. So it is important to state explicitly whether emissions are counted at the location of production or consumption. This helps to prevent double counting. The lengthy manufacturing chains of a globalised market might make this challenging. There are additional challenges with looking at renewable energy systems and electric vehicle batteries. This is because the necessary embodied energy and other effects of raw material extraction are often significant when measuring life-cycle emissions. However the local emissions at the place they are used may be small.
Standards for products
Leading standards and guidance allow official accreditation bodies to certify products as carbon neutral but not as net zero. The rationale behind this is that until organizations and their supply chains are on track for net zero, allowing a product to claim to be net zero at this point would be disingenuous and lead to greenwashing.
Financial impact
The International Monetary Fund estimates that compared to current government policies, shifting policies to bring emissions to net zero by 2050 would result in global gross domestic product (GDP) being 7 percent higher. In its estimates, the cost of emissions reductions in 2050 is less than 2% of world GDP, and the cost savings from reducing the effects of climate change are approximately 9% of world GDP.
Credibility
More and more nations and private and public-sector organizations are committing to net zero. But the credibility of these claims remains low. There is no binding regulation requiring a transition to net zero. So the overwhelming majority of net zero commitments have been made on a voluntary basis. The lack of an enforcement mechanism surrounding these claims means that many are dubious. In many sectors such as steel, cement, and chemicals, the pathway to reaching net zero in terms of technology remains unclear. Further investment in research and innovation and further regulation will probably be necessary if net zero claims are to become more credible.
Tzeporah Berman, chair of the Fossil Fuel Non-Proliferation Treaty Initiative, has criticized net zero claims by fossil fuel companies, describing them as "delusional and based on bad science".
A consortium of climate scientists has tracked net zero commitments. Their research found that net pledges drafted in law or policy documentation have grown from 7% of countries in 2020 to 75% in 2023. However, very few have met the minimum requirements for a "decent pledge". The UN Race to Zero campaign calls them "starting line criteria". This states that they must have a "plan and published evidence of action taken towards reaching the target" besides a stated pledge.
The role of carbon credits
One of the main reasons for the low credibility of many net zero claims is their heavy reliance on carbon credits. Carbon credits are often used for offsetting. They reduce or remove emissions of carbon dioxide or other greenhouse gases in order to compensate for emissions made elsewhere. Many fossil fuel companies have made commitments to be net zero by 2050. At the same time they continue to increase greenhouse gas emissions by extracting and producing fossil fuels. They claim that they will use carbon credits and carbon capture technology in order to continue extracting and burning fossil fuels. The UN has condemned such pledges as dangerous examples of greenwashing.
Criticism
Climate scientists James Dyke, Bob Watson, and Wolfgang Knorr argue that the concept of net zero has been harmful for emissions reductions. This is because it allows actors to defer present-day emissions reductions by relying on future, unproved technological fixes. Examples are carbon offsetting, carbon dioxide removal and geoengineering. "The problems come when it is assumed that these [technological fixes] can be deployed at vast scale. This effectively serves as a blank cheque for the continued burning of fossil fuels and the acceleration of habitat destruction", they said. By tracing the history of previous failures in climate policy at reducing emissions from 1988 to 2021, they said they "[arrive] at the painful realisation that the idea of net zero has licensed a recklessly cavalier 'burn now, pay later' approach which has seen carbon emissions continue to soar". They concluded: "Current net zero policies will not keep warming to within 1.5 °C because they were never intended to. They were and still are driven by a need to protect business as usual, not the climate. If we want to keep people safe then large and sustained cuts to carbon emissions need to happen now. [...] The time for wishful thinking is over."
In his 2021 report, Dangerous Distractions, economist Marc Lee said that net zero had the potential to be a dangerous distraction that reduced political pressure to reduce emissions. "A net zero target means less incentive to get to 'real zero' emissions from fossil fuels, an escape hatch that perpetuates business as usual and delays more meaningful climate action," he said. "Rather than gambling on carbon removal technologies of the future, Canada should plan for a managed wind down of fossil fuel production and invest public resources in bona fide solutions like renewables and a just transition from fossil fuels," he said.
At the 2022 United Nations Climate Change Conference (COP27), the High-Level Expert Group on the net-zero emissions commitments of non-state entities of the United Nations formed the previous March by U.N. Secretary-General António Guterres and chaired by former Canadian Minister of Environment and Climate Change Catherine McKenna released a report that stated that the carbon neutrality pledges of many corporations, local governments, regional governments, and financial institutions around the world often amount to nothing more than greenwashing and provided 10 recommendations to ensure greater credibility and accountability for carbon neutrality pledges such as requiring non-state actors to publicly disclose and report verifiable information (e.g. greenhouse gas inventories and carbon footprint accounting in prospectus for financial securities) that substantiates compliance with such pledges.
After the release of the report, Net Zero Tracker, a research consortium that includes the NewClimate Institute, the Energy and Climate Intelligence Unit, the Data-Driven EnviroLab of the University of North Carolina at Chapel Hill, and the Net Zero Initiative at the University of Oxford issued a report evaluating the climate neutrality pledges of 116 of 713 regional governments, of 241 of cities with populations greater than , and of of publicly listed companies in the 25 countries with the greatest emissions (whose pledges cover more than 90% of the gross world product) by the recommendations of the UN report and found that many these pledges were largely unsubstantiated and more than half of cities had no plan for tracking and reporting compliance with pledges.
Equity and impact
The concept of net zero has attracted criticism for the impact it could have on equity and distribution. The use of removals or carbon credits for offsetting has been particularly controversial. This is because of the possibility that offset projects themselves could have harmful effects. The ISO Net Zero Guidelines say that net zero strategies should align with the United Nations Sustainable Development Goals.This is in order to "support equity and global transition to a net-zero economy, and any subsequent UN global goals which supersede the 2030 SDGs." The UNFCCC's Race to Zero campaign says emissions reductions and removals should "safeguard the rights of the most vulnerable people and communities". It says that organizations should disclose how they will support communities affected by climate impacts and climate transition.
Country examples
As of November 2023, around 145 countries had announced or are considering net zero targets, covering close to 90% of global emissions. They include some countries that were resistant to climate action in previous decades. Country-level net zero targets now cover 92% of global GDP, 88% of emissions and 89% of the world population.
According to World Population Review, a number of countries have net zero, or net negative carbon emissions: Bhutan, Comoros, Gabon, Guyana, Madagascar, Panama, and Suriname. However, according to the World Resources Institute, all of these countries have net positive greenhouse gas emissions. These countries generally have a high level of forestation.
European Union
India
United States
See also
Carbon footprint
Carbon Neutral Cities Alliance
Carbon Neutrality Coalition
Low-carbon economy
References
Climate change and society
Greenhouse gas emissions
Climate change mitigation | Net-zero emissions | [
"Chemistry"
] | 4,847 | [
"Greenhouse gases",
"Greenhouse gas emissions"
] |
73,362,483 | https://en.wikipedia.org/wiki/Poison%20Book%20Project | The Poison Book Project is a project of the Winterthur Museum, Garden and Library and the University of Delaware to identify and catalog books known to contain poisonous substances, particularly arsenic in Paris green pigments. It was started in 2019 when Winterthur staff members Melissa Tedone and Rosie Grayburn identified a book containing Paris green in the institution's collection. The project has since confirmed at least 100 other books from libraries across the world that contain Paris green, allowing librarians to take measures to minimize the risk to those handling the books.
Origins
The project was started by Melissa Tedone, head of library materials conservation at the Winterthur Museum, Garden and Library in Delaware, United States. In 2019, whilst conserving one of the library's books, the 1857 Rustic Adornments for Homes and Taste, she noticed through a microscope that fragments of the green pigment-dyed starch used to strengthen the bookcloth were flaking away. Tedone gave samples to the museum's laboratory head Rosie Grayburn. Grayburn used an x-ray fluorescence spectrometer on the substance which showed it contained copper and arsenic.
The use of bookcloths as a cheaper replacement for leather bindings became popular in the 1840s. They were colored with pigments from a number of substances. One of these, Paris green, also known as emerald green, was an arsenic-based pigment that produced a vivid green color. It is estimated that tens of thousands of books were printed by the 1860s, when Paris green went out of fashion.
Paris green bookcloths are unlikely to be a risk to the general public, but they might cause arsenic poisoning in those who handle the books frequently, such as librarians and researchers. Paris green readily flakes into a dust, invisible to the naked eye, that coats nearby surfaces. Exposure to the dust can irritate the eyes, nose, and throat and might cause dizziness and nausea. The project has also identified other hazardous substances used in pigments, including lead, chromium, and mercury. These are less toxic than Paris green and less likely to flake when handled. These pigments include chrome yellow, which contains lead, and vermillion, which contains mercury sulfide.
Shortly after starting the project Tedone and Grayburn identified nine further books from the Winterthur collection that contained arsenic. These were removed from general circulation and sealed in plastic bags. An early project at the Library Company of Philadelphia found 28 books.
Work
The project attempts to identify individual editions of historic books that contain hazardous materials such as arsenic. The editions are added to a database that is shared so that institutions can check it against their collections. The project wants to make sure librarians are aware of potentially hazardous books and take measures to store the books safely.
The initial stage of checking new books begins with a visual assessment followed by x-ray fluorescence (XRF) spectroscopy. Positive XRF results are confirmed by Raman spectroscopy by the Winterthur/University of Delaware Program in Art Conservation. Rarely, in complex cases, a sample of material is sent for destructive testing at the University of Delaware's College of Agriculture and Natural Resources Soil Testing Program.
By April 2022 the project had identified 88 books containing Paris green, of which more than 70 contained the pigment in their bookcloths (the remainder in illustrations or labels). By September 2022 more than 101 books had been identified. The project does not seek to have the books destroyed but rather kept in controlled conditions. The project advertises itself with bookmarks showing examples of books containing Paris green; these have been sent to libraries in 49 US states and 19 countries abroad.
See also
Shadows from the Walls of Death, a book compiled by Dr. Robert C. Kedzie from samples of arsenic-laced wallpapers
References
External links
Poison Book Project at Winterthur wiki
Winterthur Museum, Garden and Library
University of Delaware
Library science
Poisoning and certain other consequences of external causes
Book databases
Arsenic
Lead poisoning | Poison Book Project | [
"Environmental_science"
] | 810 | [
"Toxicology",
"Poisoning and certain other consequences of external causes"
] |
73,362,587 | https://en.wikipedia.org/wiki/Samsung%20Galaxy%20M54%205G | The Samsung Galaxy M54 5G is a mid-range Android smartphone developed by Samsung Electronics as a part of its Galaxy M series. This phone was announced on 22 March 2023.
References
Android (operating system) devices
Samsung mobile phones
Phablets
Mobile phones introduced in 2023
Samsung Galaxy
Mobile phones with multiple rear cameras | Samsung Galaxy M54 5G | [
"Technology"
] | 66 | [
"Crossover devices",
"Phablets"
] |
73,362,644 | https://en.wikipedia.org/wiki/List%20of%20astronomers%20and%20mathematicians%20of%20the%20Kerala%20school | This is a list of astronomers and mathematicians of the Kerala school. The region surrounding the south-west coast of the Indian subcontinent, now politically organised as the Kerala State in India, has a long tradition of studies and investigations in all areas related to the branch of śāstra known as jyotiṣa. This branch of śāstra, in its broadest sense, incorporates several subdisciplines like mathematics, astronomy, astrology, horary astrology, etc. In Indian traditional jyotiṣa scholarship, there are no clear cut boundary lines separating these subdisciplines. Hence the list presented below includes all who would be called a jyotiṣa-scholar in the Indian traditional sense. All these persons will be, most likely, well versed in the subdisciplines of mathematics and astronomy as well. The list is an adaptation of the list of mathematicians and astronomers compiled by K. V. Sarma. Sarma has referred to all of them as astronomers. K. V. Sarma (1919–2005) was an Indian historian of science, particularly the astronomy and mathematics of the Kerala school. He was responsible for bringing to light several of the achievements of the Kerala school. He was editor of the Vishveshvaranand Indological Research Series, and published the critical edition of several source works in Sanskrit, including the Aryabhatiya of Aryabhata. He was recognised as "the greatest authority on Kerala's astronomical tradition".
Additional information about the persons mentioned in the list are available in books on the history of Malayalam literature and on the history of Sanskrit literature in Kerala.
List astronomers and mathematicians of the Kerala school
{| class="wikitable"
|-
! Serial number !! Name !! Period !! Works || Known for || Remarks
|-
| 1 || Vararuci I || 4th century CE || || Vararuci vākyas; introduction of Kaṭapayādi system for expressing numbers; father figure in the legend of Parayi petta panthirukulam||
|-
| 2 || Vararuci II || || Kerala-dvādasa-bhāva-vākyani, Vārarucika, Jātakarahasya || ||Might be identical with Vararuci I. Apart from the works of Vararuci I cited above, there are several works in Sanskrit all attributed to Vararuci. David Pingree in his Census of Exact Sciences in Saskrit has cited as many as eleven such works.
|-
| 3 || Haridatta || c.650-700 || Grahacāraṇinibandhana, Mahā-mārganibabndhana (NA) || Promulgation of parahita system in 683. ||
|-
| 3a || Devācārya || c. 689 || Karaṇaratna || Recognition of the precession of the equinoxes at the rate of 47 seconds per annum (modern value 50 seconds per annum) ||
|-
| 4 || Govindasvāmin || c. 800 - 850 || Mahābhāskarīya Bhāshya, Govindakṛiti (NA) Govindapaddhati (NA)|| ||Court astronomer of King Ravi Varma Kerala; teacher of Śaṅkaranārāyaṇa
|-
| 5 || Śaṅkaranārāyaṇa || 825 - 900|| Laghubhāskarīya || References to the presence of an astronomical observatory at Mahodayapuram (modern day Kodungallur). || Student of Govindasvāmin
|-
| 6 || Udayadivākara || 11th century || A commentary called Sundari on Laghubhāskarīya || ||Commented on a work of Jayadeva
|-
| 7 || Acyuta I || || Devakerala (also known as Keralajyotisṣa) || ||
|-
| 8 || Keralācarya || 12th century|| Kerala-saṁhitā, Keralīyapraśnamārga || ||
|-
| 9 || Vyāghrapāda || || Aṅkaṇasāstra|| ||A devotee of Lord Siva enshrined at Vaikom Temple in Central Kerala.
|-
| 10 || Kṛṣṇa || c. 1200 || Cintājñāna || ||
|-
! Serial number !! Name !! Period !! Works || Known for || Remarks
|-
| 11 || Kṛṣṇa-śiṣya || c. 1200 || Commentary on Hora; Prśnaphalaprāptkālanirṇaya|| || A disciple of Kṛṣṇa
|-
| 12 || Suryadeva Yajvan || 1191 - c. 1250 || Commentaries on Āryabhaṭa's Āryabhaṭīya, Manjula's Laghumānasa, Śrīpati's Jātaka-paddhati, Govindasvami's bhāṣya on Bhāskara I's Mahābhāskarīya || ||
|-
| 13 || Vidyāmādhava || || Muhūrtadarśana || ||A member of the Tulu Brahmin family of Nīlamana; six commentaries on Muhūrtadarśana have been identified.
|-
| 14 || Viṣṇu (of Nīlamana) || || A commentary on Muhūrtadarśana || ||Son of Vidyāmādhava
|-
| 15 || Govinda Bhaṭṭatiri (of Talakkuḷam) || 1237 - 1295 || Dasādhyāyi, Muhūrtaratna, Muhūrtapadavi || Progenitor of the Pazhūr Kaniyār family of astrologers ||Belongs to Alathiyur (Malappuram) village.
|-
| 16 || Tāmaranallūr || 14th century || Muhūrtavidhi (Tāmaranallūr Bhāāṣā) || ||The work uses a mixture of Malayalam and Sanskrit languages.
|-
| 17 || Nityaprakāśa Yati || 14th - 15th century || Commentaries on Hora, both in Malayalam and Sanskrit || ||
|-
| 18 || Kumāra Gaṇaka || 14th - 15th century || Raṇadīpikā || ||
|-
| 19 || Rudra I ||c. 1325 - 1400 || || ||Teacher of Parameśvara
|-
| 20 || Mādhava of Saṅgamagrāma || c. 1340 - 1425 || Golavada, Madhyamanayanaprakara, Venvaroha, Chandravakyani ||Discoverer of the infinite series expansions for sin x and cos x ||Greatest mathematician-astronomer of the Kerala School
|-
! Serial number !! Name !! Period !! Works || Known for || Remarks
|-
| 21 || Parameśvara of Vațaśśeri (Parameśvara I)|| c. 1360 - 1455 || Drigganita (1430), Bhatadipika – Commentary on Āryabhaṭīya of Āryabhaṭa I, Karmadipika – Commentary on Mahabhaskariya of Bhaskara I, Paramesvari – Commentary on Laghubhaskariya of Bhaskara I, Sidhantadipika – Commentary on Mahabhaskariyabhashya of Govindasvāmi, Vivarana – Commentary on Surya Siddhanta and Lilāvati, Goladipika – Spherical geometry and astronomy (composed in 1443 CE), Grahanamandana – Computation of eclipses (Its epoch is 15 July 1411 CE.), Grahanavyakhyadipika – On the rationale of the theory of eclipses, Vakyakarana – Methods for the derivation of several astronomical tables || Promulgator of the Drigganita system. || A proponent of observational astronomy in medieval India who had made a series of eclipse observations to verify the accuracy of the computational methods then in use
|-
| 22 || Dāmodara of Vațaśreņi (Dāmodara I) || c. 1410 - 1510 || || Teacher of Nilakantha Somayaji || Son of Parameśvara of Vațaśśeri
|-
| 23 || Ravi Nampūtiri || c. 1425 - 1500 || Ācāradīpika''' (a commentary on Muhūrtadīpika) || ||
|-
| 24 || Nīlakaņțha Sōmayāji || 1444 - 1545 || Tantrasamgraha, Golasara (Description of basic astronomical elements and procedures), Sidhhantadarpana, Candrachayaganita, Aryabhatiya-bhashya (Elaborate commentary on Aryabhatiya), Sidhhantadarpana-vyakhya, Chandrachhayaganita-vyakhya, Sundaraja-prasnottara, Grahanadi-grantha, Grahapariksakrama|| Tantrasamgraha (A comprehensive treatise on astronomy) ||
|-
| 25 || Śankara of Keļallūr || c. 1475 - 1575 || || || Nīlakaņțha Sōmayāji's younger brother. The person entrusted with task of popularizing Aryabhatiya-bhashya of Nīlakaņțha Sōmayāji.
|-
| 26 || Citrabhānu || c. 1475 - 1550 || Karaṇāmṛta (a manual on astronomical computations) || || Pupil of Nīlakaņțha Sōmayāji
|-
| 27 || Citrabhānu Śiṣya || c. 1500 - 1575 || Bhācintāvali (a work on astrology) || ||
|-
| 28 || Mazhamaṅgalaṃ Nārāyaṇan Naṃpūtiri (Nārāyaṇa I) || c. 1540-1610 || Laghuvivṛti on Pañcabodha IV, Uparāgakriyākrama (eclipse computations), two commentaries on Līlavati, one short and the other five times longer than the short, both called Kriyākramakarī and Karmadīpikā || || Son of Śaṅkara of Mahiṣamaṅgalam : Śaṅkara III
|-
| 29 || Śankara Vāriyar || c. 1500 - 1560 || Laghuvivṛti (commentary on Tantrasamgraha) || || Disciple of Nīlakaņțha Sōmayāji and protege of Āzhvāñceri Taṃprakkaḷ
|-
| 30 || Jyeṣṭhadeva || c. 1500 - 1610 || Yuktibhāṣā (in Malayalam), Gaṣitayuktibhaṣa (in Sanskrit), Dṛkkaraṇa (in Malayalam) || Yuktibhāṣā || The name is probably the Sanskritised form of his personal name in the local Malayalam language. Pupil of Teacher of Dāmodara of Vațaśreņi and teacher of Acyuta Piṣāraṭi.
|-
! Serial number !! Name !! Period !! Works || Known for || Remarks
|-
| 31 || Jyeṣṭhadeva-Śiṣya || c. 1550 - 1625 || A metrical commentary on Tantrasamgraha || || Disciple of Jyeṣṭhadeva
|-
| 32 || Māttūr Naṃpūtiri-s: Puruṣottama I and Subrahmaṇya I || c. 1475 - 1550 || Muhūrtapadvī (a condensed work in about 40 verses dealing with the prescriptions of auspicious times for functions) || The book is highly popular as attested by the availability of several commentaries on it. || Lived in Pāññāḷ village in Thrissur district
|-
| 33 || Nārāyaṇa of Kaṇvavastu: Nārāyaṇa II || 15th century || Muhūrtadīpika (A comprehensive treatise in about 400 verses on the auspicious times for functions) || ||
|-
| 34 || Rudra Vāariyar: Rudra II || c. 1475 - 1550 || Commentary on Varāhamihira's Hora, called Nauka or Vivarana, and Aṣṭamaṅgalapraśna || || Belongs to Deśamaṅgalaṃ Vāriyaṃ
|-
| 35 || Śaṅkara of Mahiṣamaṅgalam : Śaṅkara III || 1494 - 1570 || Gaṅitasāra, Candragaṅitakramaand Ayanacalanādi-gaṅita (all books on astronomy); Jatakakrama, Jātakasāra and Praśnamāla (books on astrology). All these are composed in simple Malayalam poetry or prose. His works on Sanskrit include Jātakasāra, commentaries on Pañcabodha and Laghubhāskarīya.|| Popularization of astronomical works among the masses in Kerala. || Hails from Peruvanam village near Thrissur. Spent most of his life with his teacher Parameśvaran Poṭṭi of Vāzha-māveli house in Chengannur.
|-
| 36 || Madhava of Iñcakkāzhvā : Mādhava II ||c. 1500 - 1575 || Praśnasāra (incorporates several local practices) || || Hails from Ramamangalam near Muvvattupuzha
|-
| 37 || Acyuta Piṣāraṭi : Acyuta II ||c. 1550 - 1621 || Spuṭanirṇaya, Raśigoḷaspuṭānīti, Karaṇottama (astronomical computation), Uparagakriyākrama (eclipse computations), Chāyāṣṭaka (shadow computations); commentaries on Veṅvāroha and Sūryasidhanta || Enunciation, for the first time in Indian astronomy, of the correction called "Reduction to the ecliptic". This was introduced in Western astronomy by Tycho Brahe at about the same time. || Teacher of the poet and grammarian Melpattūr Narāyaṇa Bhaṭṭa
|-
| 38 || Nīlakaṇṭha II ||16th - 17th centuries || Kanakkusāraṃ couched in maṇipravāḷaṃ style which is a mixture of Malayalam and Sanskrit languages. The work deals also with practices relating to grain transactions, house building, weighing og gold and silver, land tenure, masonry, ground measurement, etc. || ||
|-
| 39 || Nārāyaṇa III || date completely unknown || Laghudarśini (a short work on astrology) || ||
|-
| 40 || Dāmodara of Maṅgalaśreṇi (Dāmodara II) || c. 1575 - 1675 || Praśnarīti, Līlāvati-vyākhyā || || Hails from Kaṇṇāṭipparampu in Chirakkal taluk in North Malabar
|-
! Serial number !! Name !! Period !! Works || Known for || Remarks
|-
| 41 || Iṭakramañceri Nampūtiri ||c. 1625 - 1700 || Bhadradīpa-gaṇita (composed in maṇipravāḷaṃ style) || || Pupil of Dāmodara of Maṅgalaśreṇi
|-
| 42 || Maṅgalaśreṇivipra-Śiṣya ||17th century || Jyotiṣasaṃgraha (in Malayalam) || ||
|-
| 43 || Pāṇkkāṭṭu (or, Iṭakkāṭṭu) Namputiri || c. 1625 - 1725 || Praśnamārga || || Praśnamārga is the most popular and authoritative work on praśna in Kerala.
|-
| 44 || Iṭakkāṭṭu (or Eṭakkāṭṭu) Kukkuṇiyāḷ || c. 1675 0 1750 || Praśnarīti || || Pupil of Pāṇkkāṭṭu Namputiri
|-
| 45 || Rāma-śiṣya ||17th century || An explanatory rendering in Malayalam verses of the Laghuhorā of Varāahamihira || ||
|-
| 46 || Puruṣottama II ||c. 1650 - 1725 || Uparāgapariccheda (computation of solar and lunar eclipses) || ||
|-
| 47 || Putumana Somayāji ||c. 1660 - 1740 || Karaṇapaddhati (comprehensive text on astronomical computations), Nyāyaratna, Veṇvārohāṣtaka, Mānasagaṇitam, Jātakādeś || Authorship of Karaṇapaddhati || A member of the Putuvana family of Śivapuram (Thissur). Karaṇapaddhati has been commented in Sanskrit, Malayalam and Tamil. It manuscripts are available in Tamil and Telugu scripts also.
|-
| 48 || Vāsudevasvami : Vāsudeva I || || Kāaladīpa (treatise on natural astrology) || || The manuscrpt of the book was procured from Punnattūrkoṭṭa Mana, Koṭṭappaṭi, North Malabar
|-
| 49 || Śyāmaḷavaāraṇa Rāja || || Commentary on Kāaladīpa of Vāsudevasvami || || Member of Punnattūrkoṭṭa Mana
|-
| 50 || Dāmodara of Bharadvāja Gotra : Dāmodara III || || Muhūrtābharaṇa (treatise on auspicious times for functions) || || Hails from Tṛpparaṛṛoṭ village in Malabar
|-
! Serial number !! Name !! Period !! Works || Known for || Remarks
|-
| 51 || Kṛṣṇa II || || Commentary on Āryabhaṭīya in Malayalam || ||
|-
| 52 || Keralīya-dvija || || Malayalam commentary on Karaṇottama of Acyuta Piṣāraṭi || ||
|-
| 53 || Govinda-śiṣya || || Commentary called Bālaprabodhini on Jatakapaddhati of Parameśvara of Vaṭaśśeṇi || || Hails from Vaikkam
|-
| 54 || Veṇād Brāhmaṇa || || Jātakodaya (work on astrology in 103 verses) || ||
|-
| 55 || Azhvāñceri Taṃprākkaḷ || c. 1725 - 1800 || Eleven books in the form of adapted texts and commentaries covering the entire field of astronomy and astrology. Jyotiśśāstra-saṃgraha, Saṃgraha-sādhana-kṛiyā, Jātaka-sāara-saṃgraha, Jātakānīti-mārga, Phalasāra-samuccaya, etc. ||Efforts to propagate interest in studies on Jyotiṣa among members of the Nampūtiri community || Personal name unknown
|-
| 56 || Vāsudeva of Vaḷḷimana : Vāsudeva II || || A metrical commentary on Muhūrtapadavi || || Hails from Kaṇṇamaṅgalaṃ
|-
| 57 || Tuppan Nampūtiri of Iṭavaṭṭkkāt || c. 1725 - 1800 || Muhūrtapadavi VI || || Hails from Pāakoḍe in Kunnathunad
|-
| 58 || Nārāyaṇa of Iṭavaṭṭkkāt : Nārāyaṇa IV || c. 1728 - 1800 || Muhūrtapadavi VII || || Younger brother of Tuppan Nampūtiri of Iṭavaṭṭkkāt
|-
| 59 || Parameśvara II || || Commentaries called Pārameśvarī on Varāahamihira's Horā || ||
|-
| 60 || Parameśvara, pupil of Śankara : Parameśvara III || || Commentaries called Jātakacandrikā on Varāahamihira's Horā || ||
|-
! Serial number !! Name !! Period !! Works || Known for || Remarks
|-
| 61 || Bhaāradvāja-dvija || c, 1750 - 1800 || Gaṇitayuktayah (rationales of mathematical and astronomical procedures), Karaṇadarpaṇa (advanced manual on astronomical computations) || ||
|-
| 62 || Nārāyaṇa of Peruvanaṃ (Nārāyaṇa V) || || Tantrasāra || ||
|-
| 63 ||Kṛṣṇadāsa (Koccukṛṣṇan Āāśan) || 1756 - 1812 || Pañcabodha VIII (Malayalam verse), Bhāṣājātakapaddhati (Malayalam commentary on Jātakapaddhati of Parameśvara of Vaṭaśśeṇi, Kaṇkkuśāstram (mathematical procedures in Malayalam verse) || || Born in the family of Neṭumpayil in Tiruvalla taluk.
|-
| 64 || Śankara of Muktisthala : Śankara IV ||17th century || Mantrasāra, Sāmudrasāra, Ārūḍha-praśna, Lāñchana-śāstra (omens, palmistrym, astrological omens, etc.), Āyurpraśna (dealing with life longevity, Aṣṭamaṅgala, etc.) || || Hails from Mukkola
|-
| 65 || Śaṅkara V || || Jātakasāra (III), Praśnasāra (I) (both in Malayalam verse) || ||
|-
| 66 || Bhutanāthapura-Somayāji || || Praśnasāra (III) || ||
|-
| 67 || Śrīkumāra, son of Nīlakaṇṭha || || Praśnāmṛta || ||
|-
| 68 || Nārāyaṇan Iḷayatu of Maccāṭ : Nārāyaṇa VI || 1765 - 1843 || Jyotiṣa-Bhāṣāvalī, Jātakādeśaratna || || Patronised by Śaktan Tampurān
|-
| 69 || Parameśvara of Puradahanapura : Parameśvara IV || c. 1775 - 1839 || Commentary called Varadīpikā on Muhūrtapadavi II of Māttūr Puruṣottama Naṃpūtiri || || Member of Puradahanapura (Purayannur) family in Vaḷḷuvanāṭ
|-
| 70 || Śrīkaṇṭha Vāriyar of Veḷḷrakkaād || || Commentary in Malayalam on Jātakapaddhati of Parameśara of Vaṭaśreṇi || || The commentary is available in print.
|-
! Serial number !! Name !! Period !! Works || Known for || Remarks
|-
| 71 || Ghaṭigopa ||c. 1800 - 1860 || Two commentaries on Āryabhaṭīya, one in Malayalam and the other in Sanskrit || ||A devotee of God Padmanabha, the presiding deity of Thiruvananthapuram
|-
| 72 || Goda Varma, Vidvān Iḷaya Tampurān || 1800 - 1851 || Commentaries in Sanskrit on Gaṇitādhyāya of Bhāskarīya-gaṇita and the Goladhyāya of Siddhāntaśiromaṇi || || Member of the royal family of Kodungallur
|-
| 73 || Śaṅkara Varma of Kaṭattanāṭ || 1800 - 1838 || Sadratnamālā || The computation of the value of the mathematical constant correct to 17 decimal places ||
|-
| 74 || Subrahmaṇya Śāstri || 1829 - 1888 || Agaṇita (procedures for computing the positions of planets for a thousand years || || Hails from Nalleppalli in Chittur-Cochin
|-
| 75 || Subrahmaṇya of Kunnattu Mana : Subrahmaṇya II || c. 1850 - 1900 || Commentary called Bhāvaprakāśika on the Muhūrtadarśana of Vidyāmādhava || || Also known as Subrahmaṇyan Tirumunpu of Kunnattu Mana of Payyanur in North Malabar
|-
| 76 || Puruṣottaman Mūssatu : Puruṣottama III || c. 1850 - 1900 || Praśnāyana (a comprehensive work in 1018 verses) || ||
|-
| 77 || Rāma Varma Koyittampurān || 1853 - 1910 || Jyotiṣapradīpa || ||
|-
| 78 || Rāma Vāriyar of Kaikkuḷaṅra || 1833 - 1897 || Sāmudrikaśāstra, Gauḷiśāstra, commentaries on Horā and Praśnamārga || ||
|-
| 79 || A. R. Rajaraja Varma Koyittampurān || 1853 - 1918 || Karaṇapariṣkaraṇa, Pañcāṅgaśuddhipaddhati, Jyotiṣaprakāśna || ||
|-
| 80 || Vāsuṇṇi Mūsstu of Veḷḷānaśśeri || 1855 - 1914 || Commentary in Malayalam on Pañchabodha || ||
|-
! Serial number !! Name !! Period !! Works || Known for || Remarks
|-
| 81 || Punnaśśeri Nampi Nīlakaṇṭha Śarma || 1858 - 1935 || Jyotiśāstrasubodhini, Pañcabodhakriyā-Bhāṣa || || Works published by Bharata Vilasam Press, Thrissur
|-
| 82 || P. S. Purushottaman Namputiri || 1889-? || Gaṇitanirṇaya (Sanskrit with Malayalamý exposition) (Thrissur, 1940's) and several books on astrology in Malayalam including Jyothisa Sarasagraham, Varāhamihra's Bṛhat Samhitā, Brahat Jathaka Padhathi , Prasnanusthana Padhathi, Madhaveeyam, etc. || ||
|-
| 83 || K. V. A. Rama Poduval || (1881-1959) || Gaṇitaprakāśikā (Sanskrit with Malayalam exposition) (Kannur, 1950) || || Hailed from Payyannur, Kerala
|-
| 84 || V. P. Kunhikkanna Poduval || || Śuddhadṛggaṇita (Sanskrit with Malayalamý exposition) (Kozhikode, 1956) || ||
|}
See alsoA History of the Kerala School of Hindu Astronomy'' (book by K. V. Sarma)
Kerala school of astronomy and mathematics
References
Scientists from Kerala
Scholars from Kerala
Lists of Indian scientists
Lists of mathematicians | List of astronomers and mathematicians of the Kerala school | [
"Technology"
] | 5,673 | [
"Lists of people in STEM fields",
"Lists of mathematicians"
] |
73,362,722 | https://en.wikipedia.org/wiki/HD%20202908 | HD 202908, also known as HIP 105200, is a triple star located in the equatorial constellation Equuleus. It has an apparent magnitude of 7.01, making it readily visible in binoculars but not to the naked eye. When resolved, the components have apparent magnitudes of 7.25 and 8.87 respectively. The system is located relatively close at a distance of 169 light years based on Gaia DR3 parallax measurements but it is receding with a heliocentric radial velocity of .
Stellar system
Hierarchy of orbits in the HD 202908 system
The system was first observed by astronomer S.W. Burnham.
The "A" component is a double-lined spectroscopic binary that contains two solar-type stars with spectral classifications of F9 V and G0 V respectively. The pair take roughly 4 days to orbit each other.
The tertiary companion designated "B" has a class of G1.5 V, indicating that it is an ordinary G-type main-sequence star like our Sun. HD 202908 A and B both complete an eccentric orbit every 78 years.
Physical characteristics
HD 202908 Aa and Ab have masses 1.08 and 1.14 times that of the Sun and radii 97% and 106% of the Sun respectively. The former radiates 1.41 times the luminosity of the Sun from its photosphere and the latter radiates 1.16 times the Sun's luminosity. The A subsystem has an effective temperature of , giving it a whitish-yellow hue.
The B component has 97% the mass of the Sun and 91% of its radius. It radiates 84% of the Sun's luminosity from its photosphere at an effective temperature of 5,703 K. The system is estimated to be 6.4 billion years old.
References
Spectroscopic binaries
Triple star systems
G-type main-sequence stars
F-type main-sequence stars
Equuleus
BD+10 04514
202908
105200 | HD 202908 | [
"Astronomy"
] | 423 | [
"Equuleus",
"Constellations"
] |
73,362,999 | https://en.wikipedia.org/wiki/Y2K%20%282024%20film%29 | Y2K is a 2024 American apocalyptic science fiction comedy horror film directed by Kyle Mooney in his directorial debut, written by Mooney and Evan Winter. It stars Jaeden Martell, Julian Dennison, Rachel Zegler, Daniel Zolghadri, Lachlan Watson, Eduardo Franco, Mason Gooding, Mooney and Fred Durst. It follows a group of high school students who attempt to survive when the year 2000 problem causes all technology worldwide to come to life and turn against humanity.
The film had its world premiere at South by Southwest on March 9, 2024, and was theatrically released by A24 in the United States on December 6, 2024. The film has received mixed reviews from critics and has grossed $4.4 million against a budget of $15 million.
Plot
In 1999, best friends Eli, Danny, and Garrett discuss plans for New Year's Eve while their parents are out. Eli has a crush on his classmate Laura, but is too nervous to talk to her despite Danny's encouragment to kiss her at midnight. They watch as Laura and her friends Trevor, Madison, and Raleigh sneak out some alcohol and decide to crash a party held by Soccer Chris, Laura's boyfriend. While partying, Eli watches in dismay as Chris and Laura kiss at midnight until the power suddenly goes out.
As a student is found dead with a piece of a fan lodged in his head, a toy car arrives on its own and burns Trevor's face with a hairspray and a lighter, killing him. The terrified partygoers realize that all technology have become sentient and attempt to leave, but many of them are gruesomely killed. In the ensuing chaos, a VCR smashes Madison's head with a VHS tape, Chris' head is melted by a microwave, and a Tamagotchi drills through Raleigh's head. Eli, Danny, and Laura escape with juvenile delinquents Farkas, CJ, and Ash, but Danny is fatally impaled by a blade and Farkas dies when he hits the ground while attempting to rail a broken pole on his skates.
The group go to an old mill without electricity while the sentient machines kill several residents throughout the town. They also find Garrett and Laura's ex-boyfriend Jonas, and learn the threat is a collective consciousness of all electronic devices worldwide planning to enslave humanity. Laura successfully creates a kill code to shut down the algorithm, now dubbed itself as the "Amalgamation", but a computer attacks her. Eli douses it in water, shutting it down. The group is then cornered by the Amalgamation, who is using electronics to make itself bigger. Garrett tries to fend it off, but is decapitated. The group hide in portable toilets and ride them down a hill. They take refuge in a VHS store and meet musician Fred Durst, whom they encourage to join.
The group arrives at the local high school where, they learn, the machines are due to a new internet connection installed. They sneak inside and discover the townspeople have been reduced to mindless slaves by brain-implanted chips. CJ sacrifices himself to save Fred from a machine while the group learn the Amalgamation has now grown to a monstrous size and is forcing people inside it, converting them to the aforementioned slaves. Fred, Ash, and Jonas distract the machines guarding the townspeople to let Laura make her way into the Amalgamation, but it electrocutes her. Eli arrives in time to save Laura and attempt to insert the kill code himself, but fails to do so as the Amalgamation keeps electrocuting and mocking them. Eli then uses a condom Danny had given him earlier and wraps it around Laura's hand like a protective glove. While Fred, Ash, and Jonas continue distracting the machines, Eli and Laura successfully insert the kill code, shutting down the algorithm worldwide, destroying the Amalgamation. Eli shares a kiss with Laura and they reunite with the surviving townspeople as dawn breaks.
Five years later, in 2005, a now college-aged Eli, Laura, and Ash visit their friends' graves. While they leave the cemetery, Ash's new iPod starts to glitch, revealing that the algorithm has not been fully destroyed.
Cast
Production
It was announced in early March 2023 that Kyle Mooney would direct Y2K for A24. Jaeden Martell, Julian Dennison, Rachel Zegler, Lachlan Watson, Mason Gooding, The Kid Laroi, Eduardo Franco, Miles Robbins, Fred Hechinger, Alicia Silverstone, Tim Heidecker and Daniel Zolghadri joined the cast. Additionally, Weta Workshop worked on the effects for the film. In April 2023, Sebastian Chacon and Lauren Balone joined the cast.
Principal photography began in April 2023 in Ringwood, New Jersey. The following month, filming continued in Ringwood and Chatham Borough and in Clark at the recreation center, before wrapping.
Music
The soundtrack for Y2K comprises a number of songs from the 1990s; the soundtrack album is scheduled to be released on CD on January 17, 2025.
Release
It had its world premiere at South by Southwest on March 9, 2024. It was released on December 6, 2024.
Home media
The film was released video on demand on December 24, 2024.
Reception
Box office
In the United States and Canada, Y2K was released alongside Werewolves and Pushpa 2: The Rule, and was projected to gross $3–5 million from 2,108 theaters in its opening weekend. The film made $923,110 on its first day, including $300,000 from Thursday night previews. It went on to debut to $2.1 million, finishing in eighth.
Critical response
Audiences surveyed by CinemaScore gave the film an average grade of "C–" on an A+ to F scale, while those polled by PostTrak gave it a 65% overall positive score, with 50% saying they would definitely recommend it.
Clint Worthington of RogerEbert.com gave the film 1.5/4 stars, unfavorably comparing it to Brigsby Bear and concluding, "Y2K doesn't want to break stuff; it wants to dig it out of the trash and pine nostalgically for it. That's just not as interesting." Variety's Owen Gleiberman wrote, "Y2K turns out to be an attack-of-the-machines movie. Yet it's still very much a period-piece high-school comedy. So how well do the two go together? In my book, not very well... the last hour of it, the cheeky dystopian alien-tech horror farce, simply isn't very good."
Adrian Horton of The Guardian gave the film 3/5 stars, calling it "a promising if wildly uneven debut that banks heavily, often successfully, on Mooney's penchant for late 90s nostalgia." Bloody Disgusting Meagan Navarro gave it a score of 4/5, writing, "While some of its meaner horror impulses get largely forgotten by the end, it's tough to mind at all thanks to the nonstop, playful tone, killer soundtrack, wacky murder bots, and talent in front of and behind the camera that ensure a party worth rewinding the clock for."
References
External links
2024 comedy horror films
2024 directorial debut films
2024 independent films
2020s American films
2020s disaster films
2020s English-language films
2020s high school films
2020s teen comedy films
2020s teen horror films
A24 (company) films
American comedy horror films
American disaster films
American high school films
American alternate history films
American independent films
American robot films
American science fiction comedy films
American science fiction horror films
American teen comedy films
American teen horror films
Apocalyptic films
Fiction featuring the turn of the third millennium
Films about computing
Films about parties
Films about artificial intelligence
Films about slavery
Films produced by Jonah Hill
Films produced by Christopher Storer
Films set around New Year
Films set in 1999
Films set in 2000
Films set in 2005
Films shot in New Jersey
Holiday horror films
American romantic horror films
English-language comedy films | Y2K (2024 film) | [
"Technology"
] | 1,667 | [
"Works about computing",
"Films about computing"
] |
73,364,002 | https://en.wikipedia.org/wiki/Synusia | Synusia (plural Synusiae) is a term in plant ecology that refers to a layer of vegetation consisting of species with shared life forms. It has been compared with guilds in zoology.
The term synusia was introduced by Helmut Gams in 1918 although similar ideas were proposed using terms such as "Genossenschaften" (brotherhoods) and "Schicht" (society). They have been defined as ecological groups of plants that share similarities in their life-form, share the same niche and play a similar role. They can be taxonomically different but have similar habitats.
References
Plant ecology | Synusia | [
"Biology"
] | 125 | [
"Plant ecology",
"Plants"
] |
66,094,811 | https://en.wikipedia.org/wiki/Robert%20L.B.%20Tobin%20Land%20Bridge | The Robert L.B. Tobin Land Bridge is a wildlife crossing over Wurzbach Parkway in San Antonio's Phil Hardberger Park that opened on December 11, 2020. The project cost $23 million and is designed for both wildlife and pedestrians. Construction began on November 26, 2018, and was originally expected to end in April 2020.
Design
At long and wide, it is the largest wildlife bridge in the United States . With tall, noise damping corten steel walls on both sides, the bridge is designed to appear to crossers as a small hill. The bridge has a underground cistern to keep the bridge's plants irrigated via rainwater.
On April 5, 2021, a footbridge called the Skywalk opened which starts at the top of the land bridge and winds through the park's trees.
Animals using the bridge
Although animals had already been spotted crossing the bridge as of early 2021, wildlife traffic is not expected to substantially increase until the foliage planted on the bridge grows thicker.
As part of a five-year study, the Parks and Recreation Department documents wildlife using the bridge. , species include the Virginia opossum, cottaintail rabbit, white-tailed deer, coyote, rock squirrel, fox squirrel, rat, raccoon, armadillo, bobcat, gray fox, and axis deer.
See also
Wildlife crossing § Examples
References
External links
Map of the bridge
Pedestrian bridges in Texas
Bridges completed in 2020
Ecological restoration | Robert L.B. Tobin Land Bridge | [
"Chemistry",
"Engineering"
] | 295 | [
"Ecological restoration",
"Environmental engineering"
] |
66,097,812 | https://en.wikipedia.org/wiki/Maria%20Pia%20Fanti | Maria Pia Fanti (born 21 February 1957) is an Italian control theorist known for her research on topics that include discrete event dynamic systems, Petri nets, consensus, fault detection and isolation, agile manufacturing, and road traffic control. She is a professor in the Department of Electrical and Information Engineering at the Polytechnic University of Bari, where she heads the Laboratory for Control and Automation.
Education and career
Fanti studied electronic engineering at the University of Pisa, and earned a laurea there in 1983. She has been a full professor at the Polytechnic University of Bari since 2012.
Recognition
Fanti was named an IEEE Fellow in 2017 "for contributions to modeling and control of discrete event systems".
References
External links
Home page
1957 births
Living people
Italian electrical engineers
Italian women engineers
Control theorists
Fellows of the IEEE | Maria Pia Fanti | [
"Engineering"
] | 160 | [
"Control engineering",
"Control theorists"
] |
66,098,601 | https://en.wikipedia.org/wiki/The%20Ebony%20Horse | The Ebony Horse, The Enchanted Horse or The Magic Horse is a folk tale featured in the Arabian Nights. It features a flying mechanical horse, controlled using keys, that could fly into outer space and towards the Sun. The ebony horse can fly the distance of one year in a single day, and is used as a vehicle by the Prince of Persia, Qamar al-Aqmar, in his adventures across Persia, Arabia and Byzantium.
According to scholarship, the tale inspired literary stories about a flying mechanical horse in Europe. Variants from oral tradition have been collected mostly from Europe and Asia, but are also attested in Africa. Although the tale appears in the work One Thousand and One Nights, a similar story is attested earlier in the Indian Panchatantra, albeit with a flying bird-like mechanism in the shape of a Garuda.
Source
According to researcher Ulrich Marzolph, the tale "The Ebony Horse" was part of the story repertoire of Hanna Diyab, a Christian Maronite who provided several tales to French writer Antoine Galland. As per Galland's diary, the tale was told on May 13, 1709.
Summary
An Indian craftsman and inventor of magical devices arrives in the Persian city of Shiraz at the time of the New Year celebration, mounted upon a splendid artificial horse – surprisingly life-like, despite its mechanical nature. The king is so impressed with this automaton that he decides to present his son, the prince, with the marvellous steed.
The young prince wastes no time in climbing into the saddle and the horse ascends swiftly into the sky. When prince decides that he has flown high enough he tries to make the horse land, but finds that he cannot. Far from landing, the horse instead flies off with the prince, spiriting him away to unknown lands. Later, he rides the flying mechanical horse to the kingdom of Bengal and meets a beautiful princess, who becomes enamoured of him.
The young prince retells his adventures to the princess, and they exchange first pleasantries and later sweet nothings as they fall ever more deeply in love. Soon, the Persian youth convinces the Bengali princess to ride the mechanical marvel with him to his homeland of Persia.
Meanwhile, the Indian artifex had been unjustly imprisoned due to the disastrous test flight of his creation. In his cell, he sees the prince arriving with his beloved maiden. Reunited with his beloved son, the King of Persia releases the craftsman, who seizes the opportunity for revenge, using the horse to abduct the princess and disappearing swiftly over the horizon with her.
They soon arrive in the kingdom of Cashmere. The king of that country rescues the princess from the Indian and resolves to marry her, without her consent. As soon as the princess recovers from her shock, she pretends to have gone mad in order to forestall her forced marriage.
Determined to recover his beloved, the Persian prince wanders in search of her until he reaches Cashmere, where he learns his maiden is alive. He then hatches a plan to escape with his beloved on the mechanical horse back to Persia. By pretending to be a doctor, he is able to approach the princess and reveal himself to her. By having her pretend to be partially cured, the prince succeeds in persuading the king of Cashmere to openly present the ebony horse to complete the princess' healing. In an unattended moment, he and the princess use the horse to fly back to Persia, where they are happily married.
Legacy
Scholarship points that the tale migrated to Europe and inspired similar medieval stories about a fabulous mechanical horse. These stories include Cleomades, Chaucer's The Squire's Tale, Valentine and Orson and Meliacin ou le Cheval de Fust, by troubador Girart d'Amiens (fr).
The Horse and His Boy by C.S. Lewis carries key elements in both story and specifics like the structure of the Horse, from this story.
Analysis
Tale type
The tale is classified in Aarne-Thompson-Uther Index as ATU 575, "The Prince's Wings". These tales show two types of narrative:
The first one: a metalsmith and a tinkerer take part in a contest to build a mechanical marvel to impress the king and his son. A mechanical horse is built and delivered to the king, to the delight of the young prince.
The second one: the prince himself commissions from a skilled craftsman to fashion a winged apparatus to allow him to fly (eg. a pair of wings or a wooden bird).
Motifs
The flying machine
Ethnologist Verrier Elwin commented that some folk tales replace the original flying machine for a trunk or a chair, and that the motif of the equine machine is common in Indian folk-tales. Similarly, according to scholar , the flying machine, which appears in Indian variants, also appears in "many Asian tales". Hungarian professor Ákos Dömötör, in the notes to tale type ATU 575 in the Hungarian National Catalogue of Folktales (MNK), remarked that the wooden bird is an "Oriental" theme.
Origins
The tale The Ebony Horse, in particular, was suggested by mythologist Thomas Keightley, in his book Tales and Popular Fictions, to have originated from a genuine Persian source, since it does not contain elements from Islamic religion.
The oldest attestation and possible origin of the tale type is suggested to be an 11th century Jain recension of the Pancatantra, in the story The Weaver as Vishnu. In this tale, a poor weaver fashions an artificial likeness of legendary bird mount Garuda, the ride of god Vishnu. He uses the construct to reach the topmost room of the princess he fell in love with and poses as Lord Vishnu to impress his beloved.
Henry Parker, who collected some Sri Lankan variants of the tale type, identified three different origins for the horse: (1), a wooden flying horse created by a supernatural being; (2), a wooden flying horse made by human hands and "magical art"; and (3) construction of one "by mechanical art". He also suggested that a flying horse, either of wax or wood, appears in ancient Indian literature (e.g., the Rig Veda), and may date from before the time of Christ. He also saw two possible routes of diffusion: either the tale developed in India or in Sri Lanka, and was diffused by Arabs; or the image of a winged quadruped, attested in old Assyria and Mesopotamia, "spread to the early Aryans".
Another line of scholarship sees a possible predecessor of the tale type with Chinese god Lu Ban, patron deity of carpenters and builders.
Variants
Distribution
Stith Thompson sees a sparsity of the tale in European compilations, although the elements of the prince's journey on the mechanical apparatus appear in Eastern tales. In addition, Jack V. Haney argued that variants appear "in a number of Western European traditions", while German scholar locates variants in Central and Eastern Europe.
Czech scholar Karel Horálek, in Enzyklopädie des Märchens, considered India the "center of diffusion" of the tale type. Furthermore, Horálek located two major regions of distribution: in the West, in Central Europe, Southeastern Europe and Eastern Europe; in the East, India, Persia and neighbouring countries. He also considered Turkey and Caucasus as a "transitional area" between both regions.
Europe
Romani people
Philologist Franz Miklosich collected a variant in Romani language which he titled Der geflügelte Held ("The Flying Hero"), about an artifex that fashions a pair of wings.
In a Romani-Bukovina tale collected by Francis Hindes Groome, The Winged Hero, a skilled but poor craftsman begins to craft a pair of wings, after he saw them in a dream. He then uses the wings to fly to the "Ninth Region", where he sells his work to an emperor's son. The prince uses the wings and flies to another realm, where he learns from an old woman that a princess is locked away in a tower by her own father.
Transylvanian linguist Heinrich von Wlislocki collected and published a "Zigeunermärchen" titled O mánusch kástuni ciriklehá (Der Mann mit der hölzernen Vogel or The Wooden Bird).
Germany
The Brothers Grimm also collected and published a German variant titled Vom Schreiner und Drechsler ("Of The Carpenter and The Turner"; or "The Maker and the Turner"). This story was published in the first edition of their collection, in 1812, with numbering KHM 77, but omitted from the definitive edition.
A variant exists in the newly discovered collection of Bavarian folk and fairy tales of Franz Xaver von Schönwerth, titled The Flying Trunk (German: Das fliegende Kästchen).
In a variant collected from Oldenburg by jurist Ludwig Strackerjan (de), Vom Königssohn, der fliegen gelernt hatte ("About a King's Son who learned to fly"), each of the king's sons learn a trade: one becomes a metalsmith and the other a carpenter. The first one builds a fish of silver and the second fashions a pair of wooden wings. He later uses the wings to fly to another realm, where he convinces a sheltered princess he is the Archangel Gabriel.
Italy
Ignaz and Joseph Zingerle collected a variant from Merano, titled Die zwei Künstler ("The Two Craftsmen"), wherein a goldsmith and a fortune-teller compete to see who can craft a fine work: the goldsmith some gold fishes and the fortuneteller a pair of wooden wings.
Hungary
According to the Hungarian Folktale Catalogue (MNK), tale type 575, A repülő királyfi ("The Flying Prince"), registers few variants in Hungary.
Journalist Elek Benedek collected a Hungarian tale titled A Szárnyas Királyfi ("The Winged Prince"). In this story, the king traps his daughter in the tower, but a prince visits her every night with a pair of wings.
Greece
Johann Georg von Hahn collected a variant from Zagori, Greece, titled Der Mann mit der Reisekiste ("The Man with the Flying Trunk"): a rich man with an intense wanderlust commissions a flying trunk form his carpenter friend. The carpenter fills the box with "magic vapours" and the device takes flight. The rich man arrives at the tower of a princess from another realm and pretends to be the Son of God.
Bulgaria
The type is also attested in the Bulgarian Folktale Catalogue with the title "Летящият дървен кон" or Das fliegende Holzpferd ("The Flying Wooden Horse"): a goldsmith and a carpenter vie for the same woman, and arrange a mediator for their dispute (e.g., a king); in order to settle their dispute, they each fashion an apparatus (the carpenter a wooden horse, and the goldsmith a metal object); the carpenter wins, and the prince rides on the flying horse to another kingdom, where he secretly visits a princess in her tower; they escape their execution, but the wooden horse burns down, and they are separated.
Russia
The tale type is known in Russia and Slavic-speaking regions as "" (The Wooden Eagle (Dove)), after the creation that appears in the story: a wooden eagle. Professor Jack Haney stated that the tale type was "widely collected" in Russia.
Another Russian variant of the tale type is Märchen von dem berühmten und ausgezeichneten Prinzen Malandrach Ibrahimowitsch und der schönen Prinzeß Salikalla or Prince Malandrach and the Princess Salikalla, a tale that first appeared in a German language compilation of fairy tales, published by Anton Dietrich in 1831, in Leipzig. The titular prince becomes fascinated with the idea of flying after reading about it in a book of fairy tales. He wants to commission a pair of wooden wings from a carpenter.
Professor Jack V. Haney translated a variant from raconteur (1883–1943), titled The Airplane (How an Airplane in a Room Carried Off the Tsar’s Son) and also classified as ATU 575. In this tale, the plane replaces the wooden eagle.
Poland
Polish philologist and folklorist Julian Krzyżanowski, establisher of the Polish Folktale Catalogue according to the international index, classified a similar story in Poland as type 575, Skrzydlaty królewicz ("Winged Prince"): the hero either commissions a pair of wings from an artisan or steals the wings from his father, and flies away to a kingdom where a princess is locked in the tower.
In a Polish tale, "Об одном королевиче, который на крыльях летал" ("About a prince who flew on wings"), a king commissions a pair of wings from a master craftsman. The prince finds the wings, puts them on and flies to another kingdom where he visits the princess - locked in a tower - by pretending to be an angel.
Estonia
The tale type is registered in Estonia with the title Kuningapoja imetiivad ("The Magic Wings of the King’s Son"). In Estonian variants, the prince may gain either an iron hawk from the blacksmith, or wooden wings from the carpenter. He uses the contraption to fly to another kingdom.
Lithuania
The tale type also exists in Lithuania with the name Karalaičio sparnai ("The Wings of the King"). Twelve variants were registered until 1936, when folklorist Jonas Balys (lt) published his analysis of Lithuanian folktales.
Latvia
The tale type also exists in Latvia, with the title Brīnuma spārni ("Wonderful Wings"): an artisan fashions the artificial bird for the prince, who travels to another kingdom, falls in love with a princess and escapes with her on the flying device.
In a Latvian variant, "Волшебный конь" ("The Magic Horse"), a blacksmith's apprentice constructs a mechanical horse. The prince convinces the king to give it to him as a gift. He flies on the artificial horse to another kingdom by a manipulating a panel of screws, where a princess is being held at a tower. At the end of the tale, before the princess's father has a chance to execute her and the prince, they escape on the mechanical horse.
Armenia
In Armenian variants of the tale type, the prince departs either on a wooden horse or on a big wheel to the princess's kingdom. After the prince loses the flying machine, his family is separated, but reunites at the end of the story, as the princess averts a possible incestual marriage with her own son by the prince.
Azerbaijan
Azerbaijani scholarship registers a similar tale in the Azerbaijani Tale Corpus, indexed as 575, Taxta at ("Wooden Horse"): a jeweller and a carpenter bet against each other whose skills are better (or for the love of a woman); the prince is called to arbiter the dispute; the jeweller fashions a golden rooster and the carpenter a wooden horse, which the prince rides on to another kingdom; in this second kingdom, the prince absconds with the local king's daughter and both flee on the horse, but are separated when the horse burns down; the princess reaches another city and places an image to find her lover; the prince and the princess reunite.
Georgia
Georgian scholarship registers 3 variants of type 575, "Wooden Horse", in Georgia: the vehicle is a wooden horse the prince flies on to meet a princess, and sometimes the tale shows a long period of separation for the couple.
In a Georgian tale titled "Царевич и деревянный конь" ("The Tsar's Son and the Wooden Horse"), a childless royal couple has a son at last, and invites the entire kingdom. A carpenter and a metalsmith decide to create presents for the newborn prince, each in their own craft. The carpenter delivers a wooden horse that can fly. The prince delights at the present. The metalsmith, however, warns his colleague that if the prince mounts the horse, he will not know how to control it. So the carpenter returns to the palace and teaches the prince, who ends up flying on the horse to regions unknown. He reaches the roof of an old woman, in another kingdom, and she invites him in. He learns of the princess lockes in the tower and flies towards her on the horse. After escaping an attempted execution, the prince and the princess flee the kingdom and separate; the horse is destroyed in a fire. The princess goes to another kingdom and becomes its sovereign when a bird lands on her head three times. Using her royal powers, she orders a bridge to be made and a picture of her husband to be affixed on it.
Ossetia
In an Ossetian tale titled "Деревянный голубь" ("The Wooden Dove"), a metalsmith and carpenter argue whose is the more necessary skill: metalworking or woodworking. They bring their dispute to the king to judge. The metalsmith produces a golden purse and the carpenter a wooden dove. The king awards the carpenter. The king's son overhears the decision and decides to play with the wooden dove and flies to another kingdom. He meets the son of the local aldar (ruler) and learns his sister, the aldar's daughter, lives a sad life in a high tower. The prince decides to fly to her room on the wooden dove and meets her. They fall in love and she becomes pregnant. Her servants notice something amiss with the princess, and fear the aldar may execute them. The princess and the prince escape on the wooden dove and marry. The tale continues with the adventures of the three sons of the couple, who also travel on their father's wooden dove.
Asia
Middle East
A similar story, also named The Tale of the Ebony Horse, can also be found in One Hundred and One Nights, another book of Arab literature and whose original manuscripts were recently discovered.
According to professor Ruth B. Bottigheimer, an Arabic-language manuscript mentions a tale titled Fars al-abnus ('Horse of Ebony'), predating Hanna Diyab's story by two centuries. The tale was apparently part of the second volume of Tales of the Marvellous and News of the Strange, now lost.
Andrew Lang published the story with the name The Enchanted Horse, in his translation of The Arabian Nights, and renamed the prince Firouz Schah.
Folklorist William Forsell Kirby published a tale from "The Arabian Nights" titled Story of the Labourer and the Flying Chair: a poor labourer spends his earnings on an old chair. He returns to the seller wanting to know the instructions on how to use the chair. The labourer manages to control the chair, which takes him to a distant terrace. He walks from the terrace into a room where a princess was sleeping. The maiden awakes with a startle with the strange person in the room, and he presents himself as Azrael, the Angel of Death.
French orientalist François Pétit de La Croix published in the 18th century a compilation of Middle Eastern tales, titled Les Mille et un jours ("The Thousand and One Days"). This compilation also contains a variant of the tale type, named Story of Malek and the Princess Schirine: the hero Malek receives a bird-shaped box from an artisan. He enters the box and flies away to a distant kingdom. In this realm, he learns of King Bahaman, who imprisoned his daughter, the Princess Schirine, in a tower.
Turkey
German scholar located another narrative from the Ottoman Turkish Ferec baʿd eş-şidde ('Relief After Hardship'), an anonymous book dated to the 15th century. In tale nr. 13 of the compilation, titled the Weaver and the trick He played on the Carpenter, a weaver and a carpenter compete over the love of a woman, and each creates an project: the weaver a seamless shirt and the carpenter a large chest, which he tricks the weaver to go inside. The weaver flies off on the chest and reaches the kingdom of Oman, where he introduces himself as the Angel Gabriel to a princess locked in a tower. Marzolph noted that the tale was the source for Malek and Schirin, a tale contained in the work A Thousand and One Days.
China
Chinese folklorist and scholar Ting Nai-tung (zh) established a second typological classification of Chinese folktales (the first was by Wolfram Eberhard in the 1930s). According to this new system, in tale type 575, "The Prince's Wings", the main character is not a prince, and the means of transportation is either a horse or an eagle.
Iran
A Persian variant is reported to have been analysed by folklorist William Alexander Clouston's Magic Elements in the Squire's Tale. In this tale, a weaver and a carpenter in Nishapur compete to impress a local woman. The weaver sews a seamless shirt and the carpenter a magic coffer. The weaver tests the coffer and flies away to another realm. He uses the coffer to reach the castle where the daughter of the king of Oman is being held and introduces himself as the Angel Gabriel. As the story continues, he defeats an army for the King of Oman, but loses the flying coffer. At the end of the story, the king discovers the ruse, but decides to keep it a secret after the angel "Gabriel" achieved wins for him.
Central Asia
A similar tale is attested in a manuscript archived in the Institute of Oriental Studies of the Academy of Sciences of the then Soviet Union. The manuscript, indexed as A 103, is dated to the 18th century, and tentatively sourced from Central Asia. In a summary of the tale, titled "Рассказ о столяре, ткаче, дочери оманского падишаха и о чудесах, которые они пережили" ("The Story of a Carpenter, a Weaver, the Daughter of the Omani Padishah and the Wonders they Experienced"), a carpenter and a weaver compete for the hand of a woman: the weaver sews a cloth without needle nor thread, and the carpenter, in retaliation, fashions a flying box he tricks his rival to enter. The weaver travels on the flying box to Oman and falls in love with the Omani princess, to whom he introduces himself as an "arkhan". The weaver manages to trick the padishah of Oman, and actually has success in battle with the flying box, until the day the box is burnt down. The padishah discovers the weaver's secret, but promises to keep it to himself, since the princess is expecting a child.
Uzbekistan
In an Uzbek variant, titled "Столяр и портной" ("The Carpenter and The Weaver"), a carpenter and a weaver are good friends. One day, they compete against each other to test their abilities to impress a girl: the weaver creates a seamless shirt. Jealous, the carpenter builds a chest and invites the weaver for a test drive. He locks his friend inside the chest, turns a screw and the chest soars to another kingdom. The weaver reaches gets off the chest, hides it and learns the local padishah has a daughter that he locks up in a tower. The weaver uses the chest to fly up to her room, while the padishah is away on a hunt, and presents himself as Azrael.
In another Uzbek tale, "Умелые руки" ("Skillful Hands"), a boy named Rafik is taken to be apprenticed by a carpenter. One night, he has a dream about beautiful maidens. Entranced by such vision, he slowly wither, until his father and the carpenter fashion a flying wooden horse that the boy can use to look for her. He flies on the machine and lands in another place. He learns the maidens come in the shape of doves to bathe in a nearby lake and he must hide the garments of his beloved one. He does, but she escapes with the other doves. He follows her on the wooden horse until a meadow where they rest up. Rafik wakes her up and convinces her to go with him. They return to a village and marry. She gives birth to a son. Rafik flies on the horse to another kingdom, but a fire destroys the apparatus and he is stranded there. Unaware of her husband's fate, she takes their son and goes to a caravan to another city, where they set up shop in hopes of finding Rafik. Years pass, and the family is finally reunited.
South Asia
Stith Thompson and Warren Roberts's Types of Indic Oral Tales registers the existence of tale type 575, "The Prince's Wings", in modern Indian and South Asian sources. In the Indic type, the hero finds the flying horse (or other wooden mechanism), flies away to another kingdom and courts the local princess; they later escape on the mechanism, but are separated when it burns down; after their separation, they reunite.
Charles Swynnerton published an Upper Indus tale from Punjab with the title Prince Ahmed and the Flying Horse: Prince Ahmed likes to play with the sons of a goldsmith, an ironsmith, an oilman, and a carpenter, much to his father's disgust. The king decided to imprison the four youths, but the prince, their friends, intercedes in their favour: all four should prove their skills. The four fashion, respectively, six brazen fishes, two large iron fishes, two artificial giants and at last a wooden horse. Prince Ahmed climbs the horse and flies to regions unknown, where he romances a princess and brings her back to his homeland.
India
Author Mark Thornhill published an Indian tale with the title The Magic Horse. In this tale, a carpenter and a goldsmith compete over who is the most skilled craftsman. The king announces he will be the judge of the dispute and orders them to bring him their finest works. The goldsmith brings a metal fish that can swim and the carpenter a wooden horse that can move about. The king's son mounts the horse and flies away to another kingdom. In this kingdom, he learns about the princess, secluded in a tower, and who is weighed very morning against a garland of flowers so that it can be assured no man has touched her.
Anthropologist Stephen Fuchs collected a tale titled Uṛhan Ghōṛā ("The Flying Horse"), from a Baiga source named Musra, from the Bijora village near Dindori in eastern Mandla. In this tale, the raja sets up a contest between a smith and a carpenter to settle their dispute. The carpenter fashions a winged horse with an internal engine. The raja's young son rides on the horse and is carried over to another kingdom, where he sleeps with the princess. The princess's belly begins to grow and her father discovers the culprit: the foreign prince. On the day of the execution, he escapes with the princess on the winged horse, but the couple must make a hasty descent on a small island for her to give birth. Once their son is born, the family is separated: the young boy is adopted by a royal couple; the princess loss her memory and is adopted as the niece of a lower cast woman, and the prince marries another rani. Their fates converge as the prince stops an incestual marriage between son and the mother.
In another Indian variant, The Flying Horse, a carpenter creates an "airplane with an engine" for his friend, the prince. The prince rides the airplane to a marble palace in a distant kingdom across the ocean, where he meets a princess. They fall in love and she becomes pregnant. After an unfortunate accident, the prince separates from the pregnant princess, who gives birth to a boy. The two are also separated: the boy is found by a couple and his mother is rescued by prostitutes. Years later, the boy becomes a youth, buys his mother from the brothel and meets his father, who has become an old man.
Sri Lanka
Author Henry Parker published a Sri Lankan tale titled The Wax Horse: a king hides his son from the outside world due to a prophecy that the son would go away from his kingdom. One day, the young prince sees a wax horse with wings in the market and the king buys it for him. The prince climbs on the horse and flies to another kingdom, eventually meeting a princess.
In another Sri Lankan tale collected by Henry Parker, Concerning a Royal Prince and a Princess, a carpenter's son fashions a Wooden Peacock, which the Prince test drives and arrives in another kingdom. He hides the Wooden Peacock in the foliages and sees a princess bathing. Later, the prince flies to her window. The princess, then, decides to hide her lover inside her room by commissioning a man-sized lamp with a secret compartment. The princess becomes pregnant and escapes with the prince to the jungle. Her royal lover gets stranded in the sea, due to the machinations of fate, and the princess is forced to raise the child on her own. She, however, gets help from an ascetic, who, by performing "an Act of Truth", creates two other children out of flowers for the maiden to rear.
Uyghur people
In a Uyghur tale, The Wooden Horse, a carpenter and a metalsmith quarrel about who is the most skilled. The king decides to set a contest to settle their dispute: the metalsmith creates an iron fish and the carpenter a wooden horse that can fly. The king's son, the prince, is delighted at the wooden horse and asks his father to try it. The prince controls the device and begins to ascend to the skies, disappearing in the distance. He arrives at another kingdom whose king has built a "palace in the sky" to hide his daughter in. The prince visits the princess with the horse for three times, which infuriates the king. The king orders a nationwide search for the boy. The princess escapes with the prince on the flying wooden horse, but as soon as they land, the princess wants to go back to get a treasure from her mother. She leaves the prince there and flies back to her kingdom, being captured by her own father, who arranged her marriage to another man. The prince begins to notice her absence and wander about in search of food. He finds an orchard with fruits and eats them, and horns and a white beard appear on his face. He eats other fruits and reverses the transformation. He decides to collect some of them and goes back on the road. He finds a prince's retinue and gives some of the fruits to the prince - who is to marry the princess of the sky palace - to cause a physical transformation. Despairing at the situation, the retinue concoct a plan to replace the prince for the fruit seller (which was the youth's plan all along). The youth-as-the-foreign-prince meets the princess again and, after the wedding celebrations, they escape on the wooden horse.
Africa
Morocco
René Basset collected a variant in the Berber language.
Literary variants
Illustrator Howard Pyle included a tale named The Stool of Fortune in his work Twilight Land, a crossover of famous fairy tale characters (Mother Goose, Cinderella, Fortunatus, Sinbad the Sailor, Aladdin, Boots, the Valiant Little Tailor) that meet in an inn to tell stories. In The Stool of Fortune, a nameless wandering soldier is hired by a magician to shoot some animals. Angry at the unjust payment, the soldier enters the magician hut and sits on a three-legged stool, waiting for his employer. Wishing he was anywhere else, the stool obeys his command and starts to fly away. The soldier then arrives at the tower room of a unsuspecting princess and announces himself as "The King of Winds".
Sufi scholar Idries Shah adapted the tale as the children's book The Magic Horse: a King summons a woodcarver and a metalsmith to create wondrous contraptions. The woodcarver constructs a wooden horse, which draws the attention of the king's youngest son, prince Tambal.
Adaptations
The Russian variant of the tale type ATU 575, "The Wooden Eagle", was adapted into a Soviet animated film in 1953 (ru).
The tale type was also adapted into a Czech fantasy film in 1987, titled O princezně Jasněnce a ševci, který létal (Princess Jasnenka and the Flying Shoemaker). The film was based on a homonymous literary fairy tale by Czech author Jan Drda, first published in 1959, in České pohádky.
See also
The Flying Trunk, literary fairy tale by Hans Christian Andersen
Flying carpet
Pegasus, mythological flying horse
Haizum
Qianlima
Hippogriff
Tulpar
Tianma
Le cheval de bronze (opera)
References
Bibliography
Chauvin, Victor Charles. Bibliographie des ouvrages arabes ou relatifs aux Arabes, publiés dans l'Europe chrétienne de 1810 à 1885. Volume V. Líege: H. Vaillant-Carmanne. 1901. pp. 221-231.
Further reading
Cox, H.L. "'L'Histoire du cheval enchante" aus 1001 Nacht in der miindlichen Oberlieferung Franzosisch-Flanders". In: D. HARMENING & E. WIMMER (red.), Volkskultur - Geschichte - Region: Festschrift für Wolfgang Brückner zum 60. Geburtstag. Würzburg: Verlag Königshausen & Neumann GmbH. 1992. pp. 581-596.
Access date: 11th January, 2025.
External links
The Book of the Thousand Nights and One Night/The Enchanted Horse on Wikisource (translation by John Payne)
One Thousand and One Nights characters
Male characters in literature
Male characters in fairy tales
Fictional princes
Fairy tales about princes
Fairy tales about princesses
Medieval literature
Works about automation
Automata (mechanical)
Fictional objects
Magic items
Legendary flying machines
Fictional horses
Fictional Indian people
Indian folklore
Indian literature
Indian legends
Indian fairy tales
ATU 560-649 | The Ebony Horse | [
"Physics",
"Engineering"
] | 7,262 | [
"Automation",
"Magic items",
"Physical objects",
"Automata (mechanical)",
"Works about automation",
"Matter"
] |
66,099,266 | https://en.wikipedia.org/wiki/EL%20Aquilae | EL Aquilae, also known as Nova Aquilae 1927 was a nova that appeared in 1927. It was discovered by Max Wolf on photographic plates taken at Heidelberg Observatory on 30 and 31 July 1927 when it had a photographic magnitude of 9. Subsequent searches of plates taken at the Harvard College Observatory showed the nova was fainter than magnitude 11.1 on 8 June 1927 and had flared to magnitude 6.4 on 15 June 1927. It declined from peak brightness at an average rate of 0.105 magnitudes per day, making it a fast nova, and ultimately dimmed to about magnitude 21. The 14.5 magnitude change from peak brightness to quiescence was unusually large for a nova.
All novae are binary stars, with a "donor" star orbiting a white dwarf so closely that matter is transferred from the donor to the white dwarf. Pagnotta & Schaefer argued that the donor star for the EL Aquilae system is a red giant, based on its position in an infrared color–color diagram. Tappert et al. suggest that Pagnotta & Schaefer misidentified EL Aquilae, and claim that EL Aquilae is probably an intermediate polar, a nova with a main sequence donor star, based on its eruption amplitude and color.
Notes
References
Novae
Aquila (constellation)
Aquilae, EL | EL Aquilae | [
"Astronomy"
] | 277 | [
"Aquila (constellation)",
"Astronomical events",
"Constellations",
"Novae"
] |
66,099,877 | https://en.wikipedia.org/wiki/Point%20Processes | Point Processes is a book on the mathematics of point processes, randomly located sets of points on the real line or in other geometric spaces. It was written by David Cox and Valerie Isham, and published in 1980 by Chapman & Hall in their Monographs on Applied Probability and Statistics book series. The Basic Library List Committee of the Mathematical Association of America has suggested its inclusion in undergraduate mathematics libraries.
Topics
Although Point Processes covers some of the general theory of point processes, that is not its main focus, and it avoids any discussion of statistical inference involving these processes. Instead, its aim is to present the properties and descriptions of several specific processes arising in applications of this theory, which had not been previously collected in texts in this area.
Three of its six chapters concern more general material, while the final three are more specific. The first chapter includes introductory material on standard processes: Poisson point processes, renewal processes, self-exciting processes, and doubly stochastic processes. The second chapter provides some general theory including stationarity, orderliness (meaning that the probability of multiple arrivals in short intervals is sublinear in the interval length), Palm distributions, Fourier analysis, and probability-generating functions. Chapter four (the third of the more general chapters) concerns point process operations, methods of modifying or combining point processes to generate other processes.
Chapter three, the first of the three chapters on more specific models, is titled "Special models". The special models that it covers include non-stationary Poisson processes, compound Poisson processes, and the Moran process, along with additional treatment of doubly stochastic processes and renewal processes. Until this point, the book focuses on point processes on the real line (possibly also with a time dimension), but the two final chapters concern multivariate processes and on point processes for higher dimensional spaces, including spatio-temporal processes and Gibbs point processes.
Audience and reception
The book is primarily a reference for researchers. It could also be used to provide additional examples for a course on stochastic processes, or as the basis for an advanced seminar. Although it uses relatively little advanced mathematics, readers are expected to understand advanced calculus and have some familiarity with probability theory and Markov chains.
Writing some ten years after its original publication, reviewer Fergus Daly of The Open University writes that his copy has been well used, and that it "still is a very good book: lucid, relevant and still not matched in its approach by any other text".
References
Mathematics books
1980 non-fiction books
Point processes | Point Processes | [
"Mathematics"
] | 515 | [
"Point processes",
"Point (geometry)"
] |
66,100,291 | https://en.wikipedia.org/wiki/Ipswich%20window | An Ipswich window is an adapted form of the Venetian window in which the distinguishing feature is in the arrangement of the panes of glass: A Venetian window has an arched central light, symmetrically flanked by two shorter sidelights; an Ipswich window places the Venetian window within a rectangular frame, adds window panes above the central arch and extends the height of the side windows. Ipswich windows are often constructed as a variety of oriel window in which the window juts out from the wall without reaching down to the ground, but the oriel design element is not a key characteristic of an Ipswich window.
Richard Norman Shaw featured the Ipswich window in his design of the New Zealand Chambers, Leadenhall Street, London. This was built in 1871–73, but was destroyed by bombing during the Second World War.
Gallery
References
Windows
Architectural elements
Ipswich | Ipswich window | [
"Technology",
"Engineering"
] | 169 | [
"Building engineering",
"Architectural elements",
"Components",
"Architecture"
] |
66,102,528 | https://en.wikipedia.org/wiki/Spatial%20modulation | Spatial modulation is a technique that enables modulation over space, across different antennas (radio) at a transmitter. Unlike multiple-input and multiple-output (MIMO) wireless (where all the transmitting antennas are active and transmitting digital modulated symbols such as phase-shift keying and quadrature amplitude modulation), in spatial modulation, only a single antenna among all transmitting antennas is active and transmitting, while all other remaining transmitting antennas sit idle. The duty of the receiver (information theory) is: to estimate the active antenna index at the transmitter and to decode the symbol sent by the transmitting antenna.
Both processes carry a message bit. Since only one transmitting antenna is active at a particular instant, one single RF chain for the active antenna is required, unlike MIMO systems in which NT (number of transmitting antennas) antennas are active and correspondingly NT number of RF chains are required. RF chains are costly, which makes spatial modulation (SM) much cheaper to implement. Conventional MIMO systems suffer from problems such as inter-antenna interference and transmit antenna synchronization issues because all transmitting antennas are active.
Procedure
In SM, a series of information bits come to the transmitter. The transmitter divides the incoming bits in a chunk of k+l bits, where k is an exponent of two used for deciding the antenna index from which the l bits will be transmitted after applying an M-ary transmission or modulation scheme. In fact, only l bits are transmitted practically, since the antenna index also carries information of k bits, hence in total k+l bits will be decoded at the receiver.
Example
An SM transmitter with NT=2 antennas uses a binary phase-shift keying (BPSK) modulator. In that case, the transmitter can transmit a BPSK symbol by performing BPSK modulation, which will carry a message bit. The antenna index from which the BPSK symbol is transmitted carries an additional bit of information as illustrated in Table 1.
An incoming message bit string 10 matches the third row in the lookup table. In bit numbering, the most significant bit (MSB) is 1 and the least significant bit (LSB) is 0. The MSB indicates the transmitting antenna index while LSB indicates which BPSK symbol to transmit. If MSB=0 the first antenna will transmit the symbol. If MSB=1 then the second antenna will transmit. For LSB=0, BPSK symbol 1 will be transmitted whereas for LSB =1, BPSK symbol -1 will be transmitted. In this case, , so only one message bit is transmitted from the second antenna. The receiver decodes both the message bit as well as the active antenna index, effectively two message bits are decoded. Therefore, the spectral efficiency of the SM transmitter in this case is 2 bit/s/Hz.
The receiver must estimate the antenna index, as well as decode the symbol.
Advanced spatial modulation
In order to improve the spectral efficiency, SM has been modified to various advanced SM schemes:
Quadrature Spatial modulation
Improved Spatial modulation
Generalized Spatial modulation
Spatial media Based modulation
Enhanced Spatial Modulation
In some of the above advanced SM methods, more than one transmitting antenna is active at a time at the transmitter in order to improve spectral efficiency. SM and its advanced variants are used in free-space optical communication termed as Optical spatial modulation and Advanced Optical Spatial Modulation, respectively.
References
Radio resource management
Radio technology
Optical communications | Spatial modulation | [
"Technology",
"Engineering"
] | 690 | [
"Information and communications technology",
"Telecommunications engineering",
"Radio technology",
"Optical communications"
] |
66,102,846 | https://en.wikipedia.org/wiki/Marie%20Louise%20Compernolle | Marie Louise Compernolle (1909–2005) was the first female Flemish chemical engineer.
Early life
Marie Louise Compernolle was born on 17 September 1909 in Assebroek, Flanders in Belgium to Hector Compernolle (1879-1960) and Marguerite De Smet (1882-1949. She had a younger brother, Harry Compernolle (1913-1989) who later went on to become one of the two first paediatricians in Belgium. Hector owned a business which sold soil excavated in the deciduous forests around Bruges, which florists used for the cultivation of azaleas in Ghent. Marguerite ran a grocery store from their home.
Flavie De Smet, mother Marguerite's eldest sister, was married to Jules Van den bussche, head teacher of the municipal school for boys in Assebroek, and the couple supported their niece and nephew's education.
Education
Compernolle was taught first by nuns, then attended her uncle Jules's school in Assebroek, and was the only girl in the school. She then moved to the State Middle School in nearby Bruges, Until then, Compernolle had been educated in Flemish but the school taught lessons in French so she had to adjust to that. She moved on to the Royal Athenaeum after three years, where she was the first girl to be admitted. Having been a successful student, Compernolle passed the university entrance examinations to study engineering and began her studies at Ghent University in 1929. She came to specialise in chemical engineering and studied with teachers such as chemist René Goubau, engineer Gustave Magnel, and physicist Jules Verschaffelt. In 1932, she graduated with a PhD in chemical engineering from Ghent University, the first female PhD in engineering from Ghent. (Hélène Mallebrancke earned a civil engineering degree in 1923/24).
Career
Compernolle then planned to follow an academic career. Her application for the post of assistant in experimental physics to Professor Moens was turned down, with the feedback that as the country was in a period of economic crisis, priority was to be given to male rather than female applicants. The following year, Compernolle managed to be admitted, on a trial basis, as an assistant in Moens' laboratory. In October 1934, this post was converted into a full assistant role. However, two years later, the extension of the role, which should have been a mere formality, again encountered obstacles. Instead of renewing her contract, Compernolle was demoted to the title of assistant ad interim. In 1937, she resigned her post, having met so much opposition whilst her husband's career flourished.
Personal life
She married Polydoor Mortier on 12 September 1936. He was a doctor of mathematics and physics and professor, and the couple met working in Moens' Laboratory.
Compernolle finally chooses to give up her career to support her husband in his. In 1937, the couple left for the United States where Mortier had received a six-month scholarship from the Belgian American Educational Foundation to study at Brown University, Rhode Island. On their return, Mortier resumed his role in Moens' laboratory, eventually inheriting his academic chair. In an interview with Karel de Clerck for the review 't Atheneetje, Compernolle later confided that she would have "loved to remain an assistant at the university" adding “I made sure that my scientific interests were parallel to my husband's academic career. I helped him the best I could in every way. I have never regretted it."
The couple had five daughters between 1939 and 1948. A fifth daughter died at birth in 1951. The surviving daughters respectively graduated in mathematics, became a pediatrician, radiologist and dentist, as Compernolle was determined that they would have the educational opportunities she had and a professional career too.
Marie Louise Compernolle died on 11 February 2005.
References
1909 births
2005 deaths
20th-century Belgian engineers
Belgian women
Flemish women
20th-century Belgian women
Flemish engineers
Ghent University alumni
Belgian women engineers
20th-century women engineers
Belgian chemical engineers
Women chemical engineers
20th-century Belgian women scientists | Marie Louise Compernolle | [
"Chemistry"
] | 859 | [
"Women chemical engineers",
"Chemical engineers"
] |
66,103,223 | https://en.wikipedia.org/wiki/Climate%20Action%20Tracker | Climate Action Tracker (CAT) is an independent scientific project with the aim of monitoring government action to achieve their reduction of greenhouse gas emissions with regard to international agreements – specifically the globally agreed Paris Agreement aim of "holding warming well below 2°C, and pursuing efforts to limit warming to 1.5°C.". It is tracking climate action in 39 countries and the EU responsible for over 85% of global emissions. The CAT is the product of two organisations: NewClimate Institute and Climate Analytics .
The actions it tracks are:
- Effect of climate policies and action on emissions.
- Impact of pledges, targets and NDCs on national emissions over the time period to 2030, and where possible beyond.
- Comparability of effort against countries' fair share and modelled domestic pathways.
COP26
Toward the end of the COP26 climate conference, CAT produced a report concluding that the current "wave of netzero emission goals [are] not matched by action on the ground" and that the world is likely headed for more than 2.4 °C of warming by the end of the century.
References
External links
Climate Action Tracker website
Scientific organizations established in 2009
Greenhouse gas emissions | Climate Action Tracker | [
"Chemistry"
] | 239 | [
"Greenhouse gases",
"Greenhouse gas emissions"
] |
66,103,390 | https://en.wikipedia.org/wiki/Specificity%20%28symbiosis%29 | Specificity in symbiosis refers to the taxonomic range with which an organism associates in a symbiosis. In a symbiosis between a larger organism such as a plant or an animal (called host) and a microorganism (called symbiont) specificity can be looked at both from the perspective of the host i.e. how many different species of symbionts does the host associate with (symbiont specificity), as well as from the perspective of the symbiont i.e. how many different host species can a symbiont associate with (host specificity).
There are two major approaches to determine specificity, the field based (ecological) approach and the physiological (experimental) approach. In the field based approach specificity is assessed by determining the natural range of hosts or symbionts an organism associates with. In the physiological approach combinations of potential symbiotic partners are brought together artificially in the laboratory and the successful establishment of symbiosis is assessed. For example, while in the laboratory the midgut crypts of the bean bug Riptortus pedestris can be colonized by a large diversity of bacterial species in nature it only occurs with one specific Burkholderia species.
References
Symbiosis | Specificity (symbiosis) | [
"Biology"
] | 271 | [
"Biological interactions",
"Behavior",
"Symbiosis"
] |
66,103,494 | https://en.wikipedia.org/wiki/Asset%20flip | An asset flip is a type of shovelware in which a video game developer purchases pre-made assets and uses them to create numerous permutations of generic games to sell at low prices. Such games tend to be viewed by gamers as uncreative, and as diverting attention from less popular high-quality titles. Asset flips have been noted to be a problem on many online distribution platforms, especially Steam. The Nintendo Switch eShop has also been accused of allowing the sale of asset flips.
As mobile gaming became popular during the 2010s, app stores such as the Google Play Store have predominantly featured games which utilize "knockoffs" of popular IPs in a similar format. As the required investments are lower for users and publishers alike, mobile asset flips derive profits from free-to-play downloads with frequent in-game advertising and/or a freemium model.
Definition
The term asset flip was coined by games journalist James Stephanie Sterling around 2015. The term is largely applied in a pejorative sense, referring to low quality games produced using pre-made assets. Vice referred to such titles as "cobbled together, barely-functioning games". The meaning of the term received considerable debate after the launch of PUBG in 2017, as while the game made use of pre-made assets, it was successful and influential in the development of battle royale as a genre.
History
The asset flip game rose to prominence in the 2010s with the advent of pre-made royalty-free assets. The Unity store launched in 2010. Unity acknowledged the problem of "flips" in a 2015 blog post, and Sterling's initial coining of the term took place around this time. In February 2017, developers Digital Homicide Studios were accused of creating asset flips by Sterling, who reviewed one of their games, The Slaughtering Grounds. In response, they sued Sterling for US$10 million, as well as anonymous Steam users for US$18 million. These lawsuits were dismissed, and the developer's games were removed from Steam for violating their terms of service.
In September 2017, Steam removed 173 asset flip titles released by the studio Silicon Echo and associated accounts. 86 of those titles had been launched in the two months before the crackdown, accounting for approximately 10% of all games added to Steam in the period. The games were constructed out of assets from the Unity store, and were released in bulk after the studio had found a means of circumventing the $100 listing fee using a bundle mechanic. Valve released a statement addressing the move, stating: "this person was mass-shipping nearly-identical products on Steam that were impacting the store’s functionality and making it harder for players interested in finding fun games to play".
In 2018, Steam declared, after pulling the school shooting game Active Shooter, that it would "allow everything" on its platform regardless of quality. Valve engineer Erik Johnson later clarified that Steam would only remove "obvious troll" games, despite the contention of critics and gamers that asset flips are harmful to players, developers and Steam itself. The steadily increasing amount of asset flips on Steam, due to a loosening of inclusion criteria, led to what commentators called the "Steampocalypse", in which discoverability for most indie developers dropped precipitously regardless of game quality.
2018 also saw the release of Asset Flip Simulator on Steam on May 4 of that year, a game designed to criticise the practice.
Criticism
Developer Bennett Foddy has lamented the inconsistent use of the term asset flip as a pejorative, saying that some well-regarded games feature a large number of bought assets, including his own game Getting Over It which he felt could "reasonably be described" as an asset flip.
See also
Video game clone
References
Video game terminology
Video game development | Asset flip | [
"Technology"
] | 772 | [
"Computing terminology",
"Video game terminology"
] |
66,103,886 | https://en.wikipedia.org/wiki/Alloperla%20acadiana | Alloperla acadiana, the Brunswick sallfly, is a species of stonefly in the family Chloroperlidae and genus Alloperla occurring in freshwater, possibly endemic to New Brunswick. It is only known from a single male specimen taken at Pokiok, New Brunswick in 1983.
References
Plecoptera
Endemic fauna of Canada
Species known from a single specimen | Alloperla acadiana | [
"Biology"
] | 77 | [
"Individual organisms",
"Species known from a single specimen"
] |
66,105,018 | https://en.wikipedia.org/wiki/Cartesian%20parallel%20manipulators | In robotics, Cartesian parallel manipulators are manipulators that move a platform using parallel-connected kinematic linkages ('limbs') lined up with a Cartesian coordinate system. Multiple limbs connect the moving platform to a base. Each limb is driven by a linear actuator and the linear actuators are mutually perpendicular. The term 'parallel' here refers to the way that the kinematic linkages are put together, it does not connote geometrically parallel; i.e., equidistant lines.
Context
Generally, manipulators (also called 'robots' or 'mechanisms') are mechanical devices that position and orientate objects. The position of an object in three-dimensional (3D) space can be specified by three numbers X, Y, Z known as 'coordinates.' In a Cartesian coordinate system (named after René Descartes who introduced analytic geometry, the mathematical basis for controlling manipulators) the coordinates specify distances from three mutually perpendicular reference planes. The orientation of an object in 3D can be specified by three additional numbers corresponding to the orientation angles. The first manipulators were developed after World War II for the Argonne National Laboratory to safely handle highly radioactive material remotely. The first numerically controlled manipulators (NC machines) were developed by Parsons Corp. and the MIT Servomechanisms Laboratory, for milling applications. These machines position a cutting tool relative to a Cartesian coordinate system using three mutually perpendicular linear actuators (prismatic P joints), with (PP)P joint topology. The first industrial robot, Unimate, was invented in the 1950s. Its control axes correspond to a spherical coordinate system, with RRP joint topology composed of two revolute R joints in series with a prismatic P joint. Most industrial robots today are articulated robots composed of a serial chain of revolute R joints RRRRRR.
Description
Cartesian parallel manipulators are in the intersection of two broader categories of manipulators: Cartesian and parallel. Cartesian manipulators are driven by mutually perpendicular linear actuators. They generally have a one-to-one correspondence between the linear positions of the actuators and the X, Y, Z position coordinates of the moving platform, making them easy to control. Furthermore, Cartesian manipulators do not change the orientation of the moving platform. Most commonly, Cartesian manipulators are serial-connected; i.e., they consist of a single kinematic linkage chain, i.e. the first linear actuator moves the second one and so on. On the other hand, Cartesian parallel manipulators are parallel-connected, i.e. they consist of multiple kinematic linkages. Parallel-connected manipulators have innate advantages in terms of stiffness, precision, dynamic performance and in supporting heavy loads.
Configurations
Various types of Cartesian parallel manipulators are summarized here. Only fully parallel-connected mechanisms are included; i.e., those having the same number of limbs as degrees of freedom of the moving-platform, with a single actuator per limb.
Multipteron family
Members of the Multipteron family of manipulators have either 3, 4, 5 or 6 degrees of freedom (DoF). The Tripteron 3-DoF member has three translation degrees of freedom 3T DoF, with the subsequent members of the Multipteron family each adding a rotational R degree of freedom. Each member of the family has mutually perpendicular linear actuators connected to a fixed base. The moving platform is typically attached to the linear actuators through three geometrically parallel revolute R joints. See Kinematic pair for a description of shorthand joint notation used to describe manipulator configurations, like revolute R joint for example.
Tripteron
The 3-DoF Tripteron member of the Multipteron family has three parallel-connected kinematic chains consisting of a linear actuator (active prismatic P joint) in series with three revolute R joints 3(PRRR). Similar manipulators, with three parallelogram Pa limbs 3(PRPaR) are the Orthoglide and Parallel cube-manipulator. The Pantepteron is also similar to the Tripteron, with pantograph linkages to speed up the motion of the platform.
Qudrupteron
The 4-DoF Qudrupteron has 3T1R DoF with (3PRRU)(PRRR) joint topology.
Pentapteron
The 5-DoF Pentateron has 3T2R DoF with 5(PRRRR) joint topology.
Hexapteron
The 6-DoF Hexapteron has 3T3R DoF with 6(PCRS) joint topology, with cylindrical C and spherical S joints.
Isoglide
The Isoglide family includes many different Cartesian parallel manipulators from 2-6 DoF.
Xactuator
The 4-DoF or 5-DoF Coupled Cartesian manipulators family are gantry type Cartesian parallel manipulators with 2T2R DoF or 3T2R DoF.
References
Machinery | Cartesian parallel manipulators | [
"Physics",
"Technology",
"Engineering"
] | 1,094 | [
"Physical systems",
"Machines",
"Machinery",
"Mechanical engineering"
] |
66,105,247 | https://en.wikipedia.org/wiki/Computational%20neuroaesthetics | Computational neuroaesthetics is the discipline that connects neuromarketing, psychology and computer science. It represents the evolution of neuroaesthetics and computational aesthetics and investigates the brain processes of human beings involved during the aesthetic experience.
In pursuing this research objective it uses a methodology that integrates the methods and techniques which are typical of neuroscience with those typical of computational science. The visual stimuli observed by people, such as images, are computationally processed to obtain a numerical value of the aesthetic features, such as brightness and hues, which are related to the brain processes of the subjects. In doing so, computational neuroaesthetics overcomes the limits of computational aesthetics, which uses only classical measuring instruments, such as self report scales, to assess the positive emotions experienced by individuals.
Areas of application
The results that emerge from computational neuroaesthetics research can be applied in several areas. The privileged one is the field of marketing and communication, since it is possible to know which aesthetic characteristics an advertising stimulus should have to be appreciated at a deep and implicit level by consumers. These positive reactions are a factor that influences the orientation of people towards the products and the brands that are promoted.
Another area of application is design and user experience design. In fact, the aesthetics of products and phygital interfaces is a fundamental component for user experience. Computational neuroaesthetics offers useful knowledge to develop a design that respects those aesthetic parameters which are able to improve user experience. Products and services with good UX levels are perceived as better and easier to use by consumers.
In the fields of health and well-being psychology, the knowledge of this discipline represents a potential tool able to build positive and transformative aesthetic experiences which could promote patients' engagement.
Origins
Aesthetics is a discipline that, within the psychological field, has been studied over the decades by different approaches, including the gestalt and cognitivist ones. In 2005, Chatterjee, stressed the need to use a research approach able to integrate neuroaesthetics with an analytical description of the features of visual stimuli in order to obtain quantifiable parameters.
References
Interdisciplinary branches of psychology
Subfields of computer science | Computational neuroaesthetics | [
"Technology"
] | 447 | [
"Computer science",
"Subfields of computer science"
] |
47,769,434 | https://en.wikipedia.org/wiki/Phellodon%20maliensis | Phellodon maliensis is a species of tooth fungus in the family Bankeraceae. Found in Australia, it was originally described as a new species by Curtis Gates Lloyd in 1923. It was originally placed in Hydnum, until Dutch mycologist Rudolph Arnold Maas Geesteranus transferred it to the genus Phellodon in 1966.
References
External links
Fungi described in 1923
Fungi of Australia
Inedible fungi
maliensis
Fungus species | Phellodon maliensis | [
"Biology"
] | 88 | [
"Fungi",
"Fungus species"
] |
47,769,554 | https://en.wikipedia.org/wiki/Auricularia%20auricula-judae | Auricularia auricula-judae, commonly known as wood ear, jelly ear, or more historically, Jew's ear, is a species of fungus in the order Auriculariales. Basidiocarps (fruit bodies) are brown, gelatinous, and have a noticeably ear-like shape. They grow on wood, especially elder. The specific epithet is derived from the belief that Judas Iscariot hanged himself from an elder tree.
The fungus can be found throughout the year in Europe, where it normally grows on wood of broadleaf trees and shrubs. Auricularia auricula-judae was used in folk medicine as recently as the 19th century for complaints including sore throats, sore eyes and jaundice, and as an astringent. It is edible but not widely consumed.
Taxonomy
The species was first described as Tremella auricula by Carl Linnaeus in his 1753 Species Plantarum and later (1789) redescribed by Jean Baptiste François Pierre Bulliard as Tremella auricula-judae. In 1822, the Swedish mycologist Elias Magnus Fries accepted Bulliard's epithet and transferred the species to Exidia as Exidia auricula-judae. In so doing, Fries sanctioned the name, meaning that the species epithet "auricula-judae" takes priority over Linnaeus's earlier "auricula".
The species was given the name Auricularia auricula-judae in 1888 by Joseph Schröter. The specific epithet of A. auricula-judae comprises auricula, the Latin word meaning ear, and Judae, meaning of Judas. The name was criticised by the American mycologist Curtis Gates Lloyd, who said "Auricularia auricula-Judae is cumbersome and in addition is a slander on the Jews". Though critical of Lucien Marcus Underwood, saying he "would probably not have known the Jew's ear from the calves' liver", he followed him in using Auricularia auricula, which was in turn used by the American mycologist Bernard Lowy in his monograph on the genus. Despite this, Auricularia auricula-judae is the valid name for the species.
The species was long thought to be somewhat variable in colour, habitat, and microscopic features but cosmopolitan in distribution, though Lowy considered it a temperate species and doubted that it occurred in the tropics. Molecular research, based on cladistic analysis of DNA sequences, has, however, shown that Auricularia auricula-judae as previously understood comprises at least seven different species worldwide. Since A. auricula-judae was originally described from Europe, the name is now restricted to the European species. The commercially cultivated Chinese and East Asian species, still frequently marketed and described as A. auricula-judae or A. auricula, is Auricularia heimuer (black wood ear).
Vernacular names
The fungus is associated with Judas Iscariot because of the belief that he hanged himself on an elder tree after his betrayal of Jesus Christ. Folklore suggests that the ears are Judas's returned spirit, and are all that are left to remind us of his suicide. The medieval Latin name auricula Judae (Judas's Ear) matches the vernacular name in most European languages, such as the French oreille de Judas, or the German Judasohr. The species was known as "fungus sambuca" among herbalists, in reference to Sambucus, the generic name for elder. The mistranslation "Jew's Ear" appeared in English by 1544. The English common name of the fungus was originally "Judas's ear", but this was later shortened to "Judas ear" and then "Jew's ear". Common names for the fungus which refer to Judas can be traced back to at least the end of the 16th century; for instance, in the 17th century, Thomas Browne wrote of the species:
In Jews' ears something is conceived extraordinary from the name, which is in propriety but fungus sambucinus, or an excrescence about the roots of elder, and concerneth not the nation of the Jews, but Judas Iscariot, upon a conceit he hanged on this tree; and is become a famous medicine in quinsies, sore throats, and strangulations, ever since.
While the term "Jew's meat" was a deprecatory term used for all fungi in the Middle Ages, the term is unrelated to the name "Jew's ear". A further change of name to "jelly ear" was recommended in the List of Recommended Names for Fungi. The idea was criticised by the author Patrick Harding, who considered it "to be the result of political correctness where it is not necessary", and who "will continue to call [the species] Jew's ear", explaining that, while anti-Semitism was commonplace in Britain, the name "Jew's ear" is in reference to Judas, who was a Jew. However, the name is no longer favoured; the British Mycological Society recommends the name "jelly ear". Other common names include the "ear fungus" and the "common ear fungus".
Description
The fruit body of A. auricula-judae is normally up to across and up to thick. It is often reminiscent of a floppy ear, but can also be cup-shaped. It is attached to the substrate laterally and sometimes by a very short stalk. Fruit bodies have a tough, gelatinous, elastic texture when fresh, but dry hard and brittle. The upper surface is a reddish-tan-brown with a purplish tint and finely pilose (covered in tiny, grey, downy hairs). It can be smooth, as is typical of younger specimens, or undulating with folds and wrinkles. The colour becomes darker with age. The under surface is a lighter grey-brown and smooth, sometimes folded or wrinkled, and may have "veins", making it appear even more ear-like.
Entirely white fruit bodies are occasionally encountered and were once given the name Auricularia lactea, but they are merely unpigmented forms and often occur in company with ordinary, pigmented fruit bodies.
Microscopic features
The spores of A. auricula-judae are allantoid (sausage-shaped), 15-22 x 5-7 μm; the basidia are cylindrical, 65–85 × 4–5.5 μm, with three transverse septa (internal cross-walls). Hairs on the upper surface are 100-150 μm in length and 5-7.5 μm in diameter. They are hyaline, thick-walled, and have acute to rounded tips.
Similar species
In Europe, the only similar species is Auricularia cerrina, recently described on oak (Quercus) from the Czech Republic, but probably more widespread in southern Europe. It can be distinguished by its dark grey to almost black fruit bodies. The Asian Auricularia heimuer is very similar and has long been confused with A. auricula-judae. It can be distinguished microscopically by its shorter basidia and shorter spores (11–13 × 4–5 μm). The American Auricularia angiospermarum is also similar, but also has shorter basidia and spores (13–15 × 4.8–5.5 μm).
Habitat, ecology and distribution
Auricularia auricula-judae grows on the wood of deciduous trees and shrubs, particularly Sambucus nigra (elder). It is also common on Acer pseudoplatanus (sycamore), Fagus sylvatica (beech), Fraxinus excelsior (ash), Euonymus europaeus (spindle), and in one particular case, the sycamore draining board of an old sink in Hatton Garden. It very rarely grows on conifers. It favours older branches, where it feeds as a saprotroph (on dead wood) or a weak parasite (on living wood), and it causes a white rot.
Commonly growing solitarily, it can also be gregarious (in a group) or caespitose (in a tuft). Spores are ejected from the underside of the fruit bodies with as many as several hundred thousand an hour, and the high rate continues when the bodies have been significantly dried. Even when they have lost some 90% of their weight through dehydration, the bodies continue to release a small number of spores. It is found all year, but is most common in autumn.
The species is widespread throughout Europe, but is not known to occur elsewhere. It was formerly thought to be a variable species with a worldwide distribution, but molecular research, based on cladistic analysis of DNA sequences, has shown that non-European species are distinct. The cultivated "A. auricula-judae" of China and East Asia is Auricularia heimuer and, to a lesser extent, A. villosula. The North American "A. auricula-judae" on broadleaf trees is Auricularia angiospermarum, with Auricularia americana on conifers.
Uses
Culinary use
Auricularia auricula-judae has a soft, jelly-like texture. Though edible, it is not held in high culinary regard. It has been likened to "eating an Indian rubber with bones in it", while in 19th-century Britain, it was said that "it has never been regarded here as an edible fungus". The species is said to be commonly consumed in Poland. A related fungus, Auricularia heimuer, is widely used in East Asian cooking and has often been misidentified as Auricularia auricula-judae.
Auricularia auricula-judae has a mild flavour, which may be considered bland. It can be dried and rehydrated, sometimes swelling to 3 – 4 times in size. The species is not edible when raw, needing to be cooked thoroughly. A reference serving of dried fungus provides of food energy, 10.6 g of protein, 0.2 g of fat, 65 g of carbohydrate, 5.8 g ash, and 0.03% mg of carotene. Fresh mushrooms contain about 90% moisture. Dried specimens may be ground up into a powder and used to absorb excess liquid in soups and stews, as it rehydrates into tiny fragments.
Medicinal use
Auricularia auricula-judae has been used as a medicinal fungus by many herbalists. It was used as a poultice to treat inflammations of the eye, as well as a palliative for throat problems. The 16th-century herbalist John Gerard, writing in 1597, recommended A. auricula-judae for a very specific use; other fungi were used more generally. He recommends the preparation of a liquid extract by boiling the fruit bodies in milk, or else leaving them steeped in beer, which would then be sipped slowly in order to cure a sore throat. The resultant broth was probably not dissimilar to the Chinese soups that use Auricularia cornea. Carolus Clusius, writing in 1601, also said that the species could be gargled to cure a sore throat, and John Parkinson, writing in 1640, reported that boiling in milk or steeping in vinegar was "the use they are put unto that I know".
Writing in 1694, the herbalist John Pechey described A. auricula-judae by saying "It grows to the Trunk of the Elder-Tree. Being dried it will keep a good year. Boyl'd in Milk, or infus'd in Vinegarm 'tis good to gargle the Mouth or Throat in Quinsies, and other inflammations of the Mouth and Throat. And being infus'd in some proper Water, it is good in Diseases of the Eyes." The species also saw use as an astringent due to its ability to absorb water. There are recorded medicinal usages from Scotland, where it was again used as a gargle for sore throats, and from Ireland, where, in an attempt to cure jaundice, it was boiled in milk. The medicinal use of A. auricula-judae continued until at least 1860, when it was still sold at Covent Garden; at the time, it was not considered edible in the United Kingdom.
Cultural depictions
The species is referred to in Christopher Marlowe's play The Jew of Malta, where Ithamore proclaims: "The hat he wears, Judas left under the elder when he hanged himself". Later, the species was probably partially the inspiration for Emily Dickinson's poem beginning "The Mushroom is the Elf of Plants", which depicts a mushroom as the "ultimate betrayer". Dickinson had both a religious and naturalistic background, and so it is more than likely that she knew of the common name of A. auricula-judae, and of the folklore surrounding Judas's suicide.
References
Auriculariales
Fungi described in 1789
Fungi of Europe
Medicinal fungi
Judas Iscariot
Fungus species | Auricularia auricula-judae | [
"Biology"
] | 2,784 | [
"Fungi",
"Fungus species"
] |
47,769,600 | https://en.wikipedia.org/wiki/Phellodon%20niger | Phellodon niger, commonly known as the black tooth, is a species of tooth fungus in the family Bankeraceae, and the type species of the genus Phellodon. It was originally described by Elias Magnus Fries in 1815 as a species of Hydnum. Petter Karsten included it as one of the original three species when he circumscribed Phellodon in 1881. The fungus is found in Europe and North America, although molecular studies suggest that the North American populations represent a similar but genetically distinct species.
Taxonomy
Phellodon niger was originally described by Swedish mycologist Elias Fries in 1815 as a species of Hydnum. The genus Phellodon was circumscribed in 1881 by Finnish mycologist Petter Karsten to contain white-toothed fungi. Karsten included three species: P. cyathiformis, P. melaleucus, and the type, P. niger (originally published with the epithet "nigrum").
The variety Phellodon niger var. alboniger, published by Kenneth Harrison in 1961, is considered synonymous with Phellodon melaleucus. Lucien Quélet's 1886 Calodon niger is a synonym of Phellodon niger. Taxonomic synonyms (i.e., based on a different type) include: Hydnum olidum (Berkeley, 1877); Hydnum cuneatum (Lloyd 1925); and Hydnum confluens (Peck 1874). The DNA sequences of the internal transcribed spacer regions of collections from the United Kingdom were compared with collections made in the Southern United States. They showed a 92–93% similarity, suggesting that the North American populations are a different species with very similar morphological characteristics.
Phellodon niger is commonly known as the "black scented spine fungus", and the "black tooth".
Description
Fruitbodies of Phellodon niger have a cap and a stipe, and so fall into the general class of "stipitate hydnoid fungi". Individual caps are up to in diameter, but caps of neighboring fruitbodies often fuse together to create larger compound growths. Caps are flat to depressed to somewhat funnel-shaped, with a felt-like texture at first before developing concentric pits, wrinkles, and ridges. Initially whitish (sometimes with purplish tints), the cap later darkens in the center to grey, grey-brown, or black. The stipe, measuring up to long, is roughly the same color as the cap. On the underside of the caps are grey spines, up to 4 mm long. The outer covering of the stipe is a thick felty layer of mycelium that absorbs water like a sponge. In conditions of high humidity, P. niger can form striking drops of black liquid on the actively growing caps. The flesh has an odor of fenugreek when it is dry. The mushroom tissue turns bluish-green when tested with a solution of potassium hydroxide.
The ellipsoid, hyaline (translucent) spores measure 3.5–5 by 3–4 μm. The basidia (spore-bearing cells) are club-shaped, four-spored, and measure 25–40 by 5–7 μm. Phellodon niger has a monomitic hyphal system, producing generative hyphae with a diameter of 2.5–5 μm.
This fungus is considered inedible.
Habitat and distribution
The ectomycorrhizae that P. niger forms with Norway spruce (Picea abies) has been comprehensively described. It is distinguished from the ectomycorrhizae of other Thelephorales species by the unique shape of its chlamydospores. Stable isotope ratio analysis of the abundance of the stable isotope carbon-13 shows that P. niger has a metabolic signature close to that of saprotrophic fungi, indicating that it may be able to obtain carbon from sources other than a tree host.
Phellodon niger is found in continental Europe, where it has a widespread distribution, and in North America. In a preliminary assessment for a red list of threatened British fungi, P. niger is considered rare. In Switzerland, it is considered a vulnerable species. Phellodon niger was included in a Scottish study to develop species-specific PCR primers that can be used to detect the mycelia of stipitate hydnoids in soil. Collections labelled as P. niger from the United Kingdom that were DNA tested, revealed additional cryptic species. Analysis using PCR can determine the presence of a Phellodon species up to four years after the appearance of fruitbodies, allowing a more accurate determination of their possible decline and threat of extinction.
Chemistry
Phellodon niger has been a source for several bioactive compounds: the cyathane-type diterpenoids, nigernin A and B; a terphenyl derivative called phellodonin (2',3'-diacetoxy-3,4,5',6',4''-pentahydroxy-p-terphenyl); grifolin; and 4-O-methylgrifolic acid. Additional nigernins (C through F) were reported in 2011.
Fruitbodies are used to make a gray-blue or green dye.
References
External links
Fungi described in 1815
Fungi of Europe
Fungi of North America
Inedible fungi
niger
Taxa named by Elias Magnus Fries
Fungus species | Phellodon niger | [
"Biology"
] | 1,136 | [
"Fungi",
"Fungus species"
] |
47,769,616 | https://en.wikipedia.org/wiki/Gifted%20%282017%20film%29 | Gifted is a 2017 American drama film directed by Marc Webb and written by Tom Flynn. It stars Chris Evans, Mckenna Grace, Lindsay Duncan, Jenny Slate and Octavia Spencer.
The plot follows an intellectually gifted seven-year-old who becomes the subject of a custody battle between her maternal uncle and maternal grandmother.
The film was released on April 7, 2017, by Fox Searchlight Pictures, and grossed $43 million worldwide. At the 23rd Critics' Choice Awards, Grace was nominated for Best Young Actor/Actress. The film received positive reviews from critics, who praised the performances of Evans and Grace, but noted its predictability.
Plot
In St. Petersburg, Florida, seven-year-old Mary Adler, a mathematical genius, lives with her uncle and de facto guardian, Frank. Her best friend is her 43-year-old neighbor, Roberta Taylor. Frank, a former philosophy professor now boat mechanic, feels strongly that Mary should attend a normal elementary school so she can have a normal childhood.
On her first day of first grade, she shows remarkable mathematical talent, which impresses her teacher, Bonnie Stevenson. Bonnie tries to ask Frank about it but he tries to pass it off as the Trachtenberg system until Bonnie tricks Mary into completing a college math test, and confronts Frank again. It emerges that Mary's mother, Diane, had been a promising mathematician, dedicated to the Navier–Stokes problem (one of the unsolved Millennium Prize Problems) before committing suicide when Mary was six months old. Mary has lived with Frank ever since.
Despite Mary’s initial disdain for average children her own age and her boredom with their classwork, she begins to bond with them when she brings her one-eyed cat, Fred, for show-and-tell. Later, she defends a classmate from a bully on the school bus, something that Frank is not concerned about. After the incident, the principal, having discovered Mary’s math talent, encourages Frank to send Mary to a private school for gifted children, offering the opportunity of a scholarship. However, Frank turns it down, based on his family's experiences with similar schools.
The principal contacts Frank's estranged mother and Mary's maternal grandmother, Evelyn. Evelyn, a former mathematician herself, is of the opinion that people with capabilities such as Mary’s have an obligation to use their talents to further help society and therefore feels that Mary should be specially tutored in preparation for a life devoted to mathematics, much as Diane was. But Frank is adamant that his sister would want Mary to be in a normal school and have the childhood she did not have. Evelyn later sues him for full custody.
While she is on the stand in court, it is revealed that not only did Evelyn homeschool Diane, she kept her socially isolated, so that she could be completely focused on mathematics. When Diane and her teenage boyfriend ran away to a ski resort, Evelyn filed a lawsuit and threatened to charge him with kidnapping, forcing him to cut ties with Diane. She attempted suicide for the first time shortly after, something Evelyn argues was an isolated incident.
When Frank takes the stand, he admits working at a low-paying job without health insurance. His lawyer, worried that the judge will side with Evelyn due to her having a better income, health plan and home, encourages Frank to consider taking a deal orchestrated by Evelyn’s lawyer. Mary would be placed in foster care and attend the private school Evelyn wants to have her enrolled in. The foster parents live 25 minutes from Frank's home, he will be entitled to scheduled visits, and Mary will be able to decide where she wants to live after her 12th birthday.
Mary is devastated at being placed in foster care and refuses to see Frank when he tries to visit. When Bonnie sees a picture of Fred up for adoption, she alerts Frank. He retrieves the cat from the pound moments before he is about to be put down and learns that Fred was brought in due to allergy issues. Frank realizes that Evelyn, who is allergic to cats, is overseeing Mary's education in the guest house of Mary's foster home.
Frank goes to the foster home and, after reconciling with Mary, reveals to Evelyn that Diane had indeed completed the Navier–Stokes Problem, but left instructions for Frank not to publish the equation until after Evelyn’s death, revealing Diane's deep resentment towards her mother. Knowing that it meant everything for her to see Diane solve the problem, Frank offers Evelyn the opportunity to publish Diane's work if she drops her custody case, to which she agrees. Mary is placed back in the custody of Frank, returning to public school and socializing with children her age while taking college-level courses.
Cast
Production
In December 2014, Tom Flynn's screenplay was one of the 70 to make that year's Black List. In August 2015, it was announced Chris Evans had been cast in the film, with Marc Webb directing. In September 2015, Mckenna Grace, Octavia Spencer, Lindsay Duncan and Jenny Slate joined the cast, and in November 2015, Julie Ann Emery was also added.
Filming began in October 2015 in Savannah, Georgia, as well as in Tybee Island, Georgia, and finished in November 2015. Specific locations included May Howard Elementary School in Wilmington Island, Georgia and Emory University in Atlanta.
Although the film is set in St. Petersburg, Florida, screenwriter Tom Flynn was unable to convince the producers to film in Florida, because the state was no longer providing financial incentives to movie makers; that made Georgia a more financially viable option.
Mathematician Jordan Ellenberg, who was himself a child prodigy, was a mathematics consultant for the film; Webb contacted him after reading his article in The Wall Street Journal and asked him to share his experiences. Ellenberg also cameos as a professor lecturing on the partition function and Ramanujan's congruences.
Release
The film was scheduled to be released on April 12, 2017, but was pushed up to April 7, 2017.
Reception
Box office
Gifted grossed $24.8million domestically (United States and Canada), and $18.3million in other territories, for a worldwide total of $43.1million, against a budget of $7.0million. It had a very limited release (56 screens) its first weekend, finishing No.16 at the domestic box office, then expanded into wide release, spending the next four weekends in the Top10.
Critical response
Colin Covert of the Star Tribune gave the film 3/4 stars, saying, "Sure, it's a simple, straightforward film, but sometimes that's all you need as long as its heart is true." On Evans' performance, Owen Gleiberman of Variety said, "Chris Evans, abashed and rumpled, with a grease monkey’s can’t-be-bothered-to-shave beard, gives an engaged performance, exuding a homespun warmth we haven’t seen in the “Captain America” films." Richard Roeper gave the film 4 out of 4 stars and said, "Gifted isn't the best or most sophisticated or most original film of the year so far – but it just might be my favorite."
Accolades
See also
Proof, about a complex proof written by a mathematician or his daughter
Little Man Tate, similar theme of prodigy and reluctance of the single parent to accept their need for better education
List of films about mathematicians
List of fictional child prodigies
References
External links
2010s American films
2010s English-language films
2010s legal drama films
2017 drama films
2017 films
American courtroom films
American legal drama films
Films about children
Films directed by Marc Webb
Films scored by Rob Simonsen
Films set in Florida
Films shot in Georgia (U.S. state)
Fox Searchlight Pictures films
Gifted education
Women in mathematics | Gifted (2017 film) | [
"Technology"
] | 1,586 | [
"Women in science and technology",
"Women in mathematics"
] |
47,770,094 | https://en.wikipedia.org/wiki/All%20of%20Us%20%28initiative%29 | The All of Us Research Program (previously known as the Precision Medicine Initiative Cohort Program) is a research program created in 2015 during the tenure of Barack Obama with $130 million in funding that aims to make advances in tailoring medical care to the individual. The mission of All of Us is to accelerate health and medical breakthroughs, enabling individualized prevention, treatment and care.
The project aims to collect genetic and health data from one million volunteers. The initiative was announced during the 2015 State of the Union Address, and is run by the National Institutes of Health (NIH). The program is bilingual, with information and materials available in Spanish and English.
Who can enroll
Eligible adults (18 and over) can enroll with the program. People who are not eligible are those in prison or people who cannot consent on their own
According to a sample consent form released in June 2018, participation in All of Us is voluntary and does not affect a participant's medical care. The form explains that if a participant quits the program, their samples will be destroyed. Children may also be able to enroll in the program.
By January 2018 an initial pilot project had enrolled about 10,000 people and 2022 was targeted for one million people. As of May 2019, enrollment numbers at the one-year launch anniversary are 187,000+ participants. More than 132,000 have already given biosamples.
The NIH reported in May 2018 that they were pleased with the high enrollment by underrepresented groups including communities of color and individuals with lower incomes. Up to three-quarters of beta phase participants came from those communities.
Program partners
All of Us has more than 100 partners and champions working together to implement and support the mission and goals of the research program. Google life sciences startup Verily Life Sciences, a Google "moonshot" with a goal of "transform[ing] the way we detect, prevent, and manage disease" is one partner.
The initiative was identified by a 2019 review as involving the public in every stage of the research.
Program budget
The All of Us Research Program budget has increased every year since it launched: FY2016 - $130 million; FY2017 - $230 million; and FY2018 - $290 million.
Responses to the Initiative
Professor Kenneth Weiss from Pennsylvania State University, in a skeptical review of this project in 2017, suggested that the funding could be better spent elsewhere.
The project suffered backlash in 2024 to their use of umap plotting to depict ancestry, rather than principal components analysis.
Program progress
Enrollment
The research program was launched for national enrollment on May 6, 2018. In the summer of 2019, one year after its official launch, All of Us had enrolled 230,000 participants, which represents almost one quarter of the program's goal of 1,000,000 individuals. Approximately 80% of those people are from groups that have been traditionally underrepresented in biomedical research. One of All of US's main goals is to include many people from diverse ancestries. By June 2020, enrollment reached approximately 350,000 individuals.
All of Us Researcher Workbench
On May 27, 2020, the All of Us research program announced the launch of their research platform, the All of Us Researcher Workbench, for beta testing. Select data collected by the initiative, including electronic health records and survey responses from the first 225,000 program participants, will be available to approved researchers through the workbench. Researchers may apply for access to the data if they have an NIH eRA Commons account (for identity verification) and are affiliated with an institution that has signed a data use agreement with All of Us.
Response to COVID-19 pandemic
In June 2020, the NIH announced that research materials collected as part of the All of Us initiative will be used to address the COVID-19 pandemic. Blood samples collected from recent volunteers will be tested for SARS-CoV-2 antibodies in order to track prior infections within the US population. Electronic health records shared by All of Us participants will also be evaluated for potential patterns associated with SARS-CoV-2 infection. All of Us also added monthly participant surveys with questions about the physical, mental, and socioeconomic impacts of the COVID-19 pandemic.
Administration
The founding program director was Eric Dishman, who stepped down to become the Chief Innovation Officer. In 2019, Joshua Denny was selected to be the second director. In October 2016, the project was renamed "All of Us".
See also
100,000 Genomes Project (UK)
21st Century Cures Act
Baseline Study
Precision medicine
precisionFDA
References
External links
Join All of Us homepage to join the All of Us research program
All of Us homepage at the National Institutes of Health
NIH Innovation account on USAspending.gov
American medical research
Supercomputing
Biological databases
Biobank organizations
Epidemiology | All of Us (initiative) | [
"Technology",
"Environmental_science"
] | 992 | [
"Epidemiology",
"Environmental social science",
"Supercomputing"
] |
47,770,289 | https://en.wikipedia.org/wiki/TvOS | tvOS (formerly Apple TV Software) is an operating system developed by Apple for the Apple TV, a digital media player. In the first-generation Apple TV, Apple TV Software was based on Mac OS X. The software for the second-generation and later Apple TVs is based on the iOS operating system and has many similar frameworks, technologies, and concepts.
The second- and third-generation Apple TV have several built-in applications, but do not support third-party applications.
On September 9, 2015, Apple announced the fourth-generation Apple TV, with support for third-party applications. Apple also changed the name of the Apple TV operating system to tvOS, adopting the camel case nomenclature that they were using for their other operating systems, iOS and watchOS.
History
On October 30, 2015, the fourth-generation Apple TV became available; it shipped with tvOS 9.0. On November 9, 2015, tvOS 9.0.1 was released, primarily an update to address minor issues.
tvOS 9.1 was released on December 8, 2015, along with OS X 10.11.2, iOS 9.2, and watchOS 2.1. Apple also updated the Remote apps on iOS and watchOS, enabling basic remote functionality for the fourth-generation Apple TV (previously, the app only worked with past versions of Apple TV).
On November 25, 2015, Facebook debuted their SDK for tvOS, allowing applications to log into Facebook, share to Facebook, and use Facebook Analytics in the same way that iOS applications can.
On December 2, 2015, Twitter debuted their login authentication service for tvOS – "Digits" – allowing users to log into apps and services with a simple, unique code available online.
On June 13, 2016, at WWDC 2016, Apple SVP of Internet Services Eddy Cue announced tvOS 10. It brought new functionality, such as Siri search improvements, single sign-on for cable subscriptions, a dark mode, and a new Remote application for controlling the Apple TV; it was released on September 13, 2016, along with iOS 10.
On June 4, 2018, at WWDC 2018, tvOS 12 was announced. It brought support for Dolby Atmos E-AC3 and was released on September 17, 2018, along with iOS 12.
On April 13, 2020, it was discovered that Apple's Siri Smart Speaker HomePod began to run variants of the tvOS software.
On June 22, 2020, at WWDC 2020, tvOS 14 was announced. It brought support for the Home app and 4K YouTube videos and was released on September 16, 2020, along with iOS 14 and iPadOS 14.
On June 7, 2021, at WWDC 2021, tvOS 15 was announced. It brought new features and improvements, including SharePlay, a new "Shared with You" section on the TV app, and the ability to play content via voice command. It was released on September 20, 2021, along with iOS 15 and iPadOS 15.
On June 6, 2022, at WWDC 2022, tvOS 16 was announced. It brought support for Nintendo Switch's Joy-Con and Pro Controllers and additional Bluetooth and USB game controllers. It was released on September 12, 2022, along with iOS 16.
On June 5, 2023, at WWDC 2023, tvOS 17 was announced. tvOS 17 brings new features, such as support for FaceTime and video conferencing apps when paired with a iPhone or iPad, a redesigned control center interface, and third-party VPN support. It was released on September 18, 2023, along with iOS 17 and iPadOS 17.
On June 10, 2024, at WWDC 2024, tvOS 18 was announced. It was released on September 16, 2024, along with iOS 18 and iPadOS 18.
Features
tvOS 9 shipped with several new features on the fourth-generation Apple TV. One major new feature was the ability to move through the interface with the new touchpad remote using multi-touch gestures. It also introduced a new App Store in which users can download and install new applications (such as apps and games) made available by developers for the Apple TV and tvOS. tvOS 9 adds support for Siri, which offers a multitude of features such as a cross-application search for a movie/TV show, rewind, fast forward, name and actor/director of the current movie, and skip back 15 seconds. tvOS added support for an application switcher on the Apple TV, more application customization options, cinematic screensavers, and control the TV using the included Siri Remote with the built-in support for HDMI-CEC in tvOS. In addition, tvOS allows the user to control the Apple TV in many different ways, such as using the included Siri Remote, pairing a third-party universal remote, pairing an MFi Gamepad to control games, using the Remote app on iOS, and pairing a Bluetooth keyboard to aid in the typing experience of the user.
Accessibility
tvOS was designed based on iOS, as such tvOS inherited many of the accessibility features of iOS and macOS.
tvOS includes the Apple technologies of VoiceOver, Zoom, and Siri to help the blind and those with impaired vision. VoiceOver, Apple's screen reader, is available in more than 30 languages and enables visually impaired users to know what is on the visual display and input responses to on-screen prompts. VoiceOver uses gestures similar to other Apple products (flicks, taps, and the rotor).
Like other Apple products such as the iPhone with a three click sequence to the home button to activate accessibility features, with Apple TV's tvOS, a user can activate VoiceOver without any installation process. One needs only to triple-click the Menu button on the Siri Remote and the Apple TV will guide the user through the complete initial setup, a task that is non-trivial to the visually impaired in most comparable products on the market.
Another accessibility feature is to increase contrast on the screen which acts by reducing the transparency of background elements on Movie and TV Show pages, menu tabs, and other parts of the operating system. High-contrast can also be turned on, with a cursor to better delineate the focused content. The user can also opt to turn on Reduce Motion which in some screen actions, such as moving between app icons on the Home screen and launching apps are visually simpler which is of benefit to reduce strain on the eyes.
tvOS enables users to watch movies with audio descriptions of what is being shown on the screen. Movies with audio descriptions are displayed with the AD (Audio Description) icon in the iTunes Store for tvOS and in iTunes on a Macintosh or Windows PC.
Pairing a Bluetooth keyboard with the tvOS on the Apple TV enables another accessibility feature that also is an incorporation of VoiceOver. When typing, VoiceOver mirrors with an audio voice, each character pressed on the keyboard and repeated again when it is entered. The Apple TV is designed to work with the Apple Wireless Keyboard or the Apple Magic Keyboard. It will work however with almost any brand of Bluetooth keyboard.
Apple TV with and without tvOS supports closed captioning, so the deaf or hard of hearing can experience TV episodes and feature-length movies. Compatible episodes and movies are denoted with a CC (closed captioning) or SDH (subtitles for the deaf or hard-of-hearing) icon in the iTunes Store either on the Apple TV or in iTunes itself. The viewer can customize the captions in episodes or movies with styles and fonts that are more conducive to their hearing and/or visual impairment.
The Touch surface on the Siri Remote is customizable. Tracking when set to Fast adjusts the thumb movements made to amplify the distance in relation to how far the thumb has moved on the glass touchpad. Conversely when tracking is set to slow, larger movements of the thumb on the touchpad will tune down the distance that is traversed on the screen. This can help people with disabilities.
Apple's Remote app on iOS devices allows control of the Apple TV from an iPhone, iPad or iPod Touch. The iOS remote app increases the accessibility of the Apple TV by enabling Switch Control. Switch Control is a unique Apple technology that enables navigation sequentially through onscreen items and perform specific actions such as selecting, tapping, dragging, typing using third party Bluetooth-enabled switch hardware made for those with handicaps.
Development
tvOS 9 shipped with all-new development tools for developers, adding support for a new SDK for developers to build apps for the TV including all of the APIs included in iOS 9 such as Metal. It also adds the tvOS App Store which allows users to browse, download, and install a wide variety of applications. In addition, developers can now use their own interface inside of their application rather than only being able to use Apple's interface. Since tvOS is based on iOS, it is easy to port existing iOS apps to the Apple TV with Xcode while making only a few refinements to the app to better suit the larger screen. Apple provides Xcode free to all registered Apple developers. To develop for the new Apple TV, it is necessary to make a parallax image for the application icon. In order to do this, Apple provides a Parallax exporter and previewer in the development tools for the Apple TV.
Version history
Information about software updates for Apple TV (2nd generation) onwards is published on Apple's support website.
Supported OS releases
Apple TV Software 1.0
Apple TV software 1.0 presented the user with an interface similar to that of Front Row. Like Front Row on the Mac, it presents the user with seven options for consuming content. Movies, TV Shows, Music, Podcasts, Photos, Settings, and Sources. It was a modified version of Mac OS X 10.4 Tiger.
Apple TV Software 2.0
In February 2008, Apple released a major and free upgrade to the Apple TV, labelled "Take Two" (2.0). This update did away with Front Row and introduced a new interface in which content was organized into six categories, all of which appeared in a large square box on the screen upon startup (movies, TV shows, music, YouTube, podcasts, and photos) and presented in the initial menu, along with a "Settings" option for configuration, including software updates.
Apple TV Software 3.0
In October 2009, Apple released another update for the Apple TV called "Apple TV Software 3.0". This update replaced the interface in version 2.0 with a new interface which presented seven horizontal columns across the top of the screen for the different categories of content (Movies, TV Shows, Music, Podcasts, Photos, Internet, and Settings). This update also added features such as content filtering, iTunes Extras, new fonts, and a new Internet radio app. One new feature in particular was the 'Genius' playlist option allowing for easier and more user friendly playlist creating.
Apple TV Software 4
Apple TV Software 4, based on iOS 4 and 5, was the first version of Apple TV Software available on the Apple TV (2nd generation). It ended support for the Apple TV (1st generation). Apple TV Software 4.4 brought My Photo Stream, AirPlay mirroring (from iPhone 4S and iPad 2), NHL, Wall Street Journal, slideshow themes and Netflix subtitles. Contrary to rumors and code found in iOS 5, the release did not bring support for Bluetooth or apps to the Apple TV (2nd generation).
Apple TV Software 5
On September 24, 2012, Apple TV (2nd generation) onwards received the Apple TV Software 5 software update, based on iOS 5 and 6, with Shared Photo Streams, iTunes account switching, better AirPlay functionality, and Trailers searching, among other smaller improvements.
Apple TV Software 6
On September 20, 2013, Apple TV (second generation) onwards received the Apple TV Software 6 software update, based on iOS 7, with iTunes Radio and AirPlay from iCloud.
Apple TV Software 7
On September 18, 2014, the third generation Apple TV received the Apple TV Software 7.0 software update based on iOS 8, with a redesigned UI, Family Sharing and peer-to-peer AirPlay. This release dropped support for the second generation Apple TV.
tvOS 9
tvOS 9 is based on iOS 9, with adaptations made for a television interface. It was announced on September 9, 2015, alongside the new iPad Pro and iPhone 6S. Tim Cook introduced tvOS, saying that it was time for the Apple TV to gain a modern OS with support for apps, as they are "the future of TV." It will only be available on the Apple TV (4th generation), released in October 2015. It adds a native SDK to develop apps, an App Store to distribute them, support for Siri, and universal search across multiple apps.
tvOS 10
tvOS 11
tvOS 12
tvOS 13
tvOS 14
tvOS 15
tvOS 16
tvOS 17
tvOS 18
See also
Other operating systems developed by Apple:
iOS
iPadOS
watchOS
macOS
visionOS
Notes
References
External links
– Official site for Apple TV (Hardware)
Apple Inc. operating systems
IOS
Proprietary operating systems
Streaming media systems
Products introduced in 2015
Television operating systems | TvOS | [
"Technology"
] | 2,747 | [
"Streaming media systems",
"Telecommunications systems",
"Computer systems"
] |
47,770,413 | https://en.wikipedia.org/wiki/Penicillium%20subrubescens | Penicillium subrubescens is a species of the genus of Penicillium which produces high amounts of inulinase.
References
Further reading
subrubescens
Fungi described in 2013
Fungus species | Penicillium subrubescens | [
"Biology"
] | 43 | [
"Fungi",
"Fungus species"
] |
47,770,617 | https://en.wikipedia.org/wiki/Pipe%20marking | In the process industry, chemical industry, manufacturing industry, and other commercial and industrial contexts, pipe marking is used to identify the contents, properties and flow direction of fluids in piping. It is typically carried out by marking piping through labels and color codes. Pipe marking helps personnel and fire response teams identify the correct pipes for operational, maintenance or emergency response purposes.
Background
Pipes are used extensively in commercial and industrial buildings and on industrial plant (e.g. oil refineries) to transfer fluids between items of plant and equipment. Positive identification assists operations personnel to correctly identify plant when carrying out routine or maintenance activities, and for emergency personnel when responding to emergencies. Pipe marking is particularly important for identification where pipes run along pipe racks, through walls and bulkheads and through floors.
A range of corporate, national and international codes, standards and regulations are in use around the world.
National standards: United States
ANSI/ASME Standards
In the United States, Occupational Safety and Health Administration regulations recommend following American Society of Mechanical Engineers Standard A13.1-2015 - Scheme for the Identification of Piping Systems.
The standard states that labels should be placed where easily viewed by a person standing near the pipe at any of the following points:
Valves and flanges.
Approximately every to on straight sections.
A pipe passes through a wall or floor.
Any pipe direction changes, such bends or junctions.
2015 revisions
2015 revisions added oxidizing materials to the existing 'Flammables' classification. The other major change allowed and encouraged labels to incorporate the GHS signal word, hazard pictograms, and hazard statements. This addition helped identify additional dangers when dealing with materials that fit into multiple categories, like hydrogen sulfide, which is both flammable and toxic.
IIAR Bulletin #114
In 2014, the International Institute of Ammonia Refrigeration introduced a specialized label design for use when marking pipes associated with refrigeration systems using ammonia, including information such as the physical state, pressure and purpose in the system.
NFPA 99C 2002
The National Fire Protection Association have a special labeling system in the standard for Health Care Facilities, such as hospitals and dentistry offices. This standard puts more emphasis on gases found in Medical gas supply systems, which consist of both oxidizing gases and gases that displace oxygen.
National standards: United Kingdom
In the United Kingdom there are three principal regulations that mandate the marking of equipment and piping:
Classification, Labelling and Packaging of Chemicals (Amendments to Secondary Legislation) Regulations 2015,
Health and Safety (Safety Signs and Signals) Regulations 1996,
Provision and Use of Work Equipment Regulations 1998,
The regulations require that vessels containing hazardous substances together with the pipes containing or transporting such substances must be labelled or marked with the relevant hazard pictograms or pipe marking. The labels used on pipes must be positioned visibly in the vicinity of the most hazardous points, such as valves and joints; at both sides of bulkheads and floor penetrations; and at reasonable intervals.
The regulations do not specify a specific marking system, but BS EN ISO 1710 Graphical symbols — Safety colours and safety signs is often used.
BS 1710 Safety colours and signs
A widely used British Standard (BS) for marking equipment is:
BS 1710:2019 Graphical symbols — Safety colours and safety signs — Registered safety signs
The Standard stipulates the colours to be used. These are as follows:
In addition to the basic colours, certain safety colours are used:
The arrangement of markings is for the safety colour to be between bands of the basic colour.
Firewater service would be:
The pipe contents must be identified adjacent to the banding. This can be done by giving either:
The full name
Abbreviation
Chemical symbol
Refrigerant number
Coloured bands (user specified)
The direction of flow should also be identified near the banding.
Examples using this system are as shown.
National standards: India
IS 2379 Pipelines Identification Colour Code
The Indian Standard IS 2379 provides for a ground colour and a coloured band on piping to identify material.
Colour bands of 25 mm to 100 mm width are placed at locations such as battery limits, intersections, near valves, at walls, starting and terminating points. There is a large range of bands which define the contents of the line. For example, for oils.
National standards: Australia
Pipes, ducts and conduits are identification by the Australian Standard AS 1345—1995 “Identification of the contents of pipes, conduits and ducts”
International standards
ISO 14726 Ships and marine facilities
Ships and marine facilities must conform to an international standard for piping systems identification. This is ISO 14726:2008 Ships and marine technology — Identification colours for the content of piping systems.
This is a two-colour banded marking system. The main colour shows what the fluid is being used for. This is on either side of the secondary colour which indicates what the substance actually is. The main colours are as follows:
Black - Waste media
Blue - Fresh water
Brown - Fuel
Green – Sea water
Grey - Non-flammable gases
Maroon - Air and sounding pipes
Orange - Oils other than fuels
Silver - Steam
Red - Fire fighting
Violet - Acids, alkalis
White - Air in ventilation systems
Yellow - Flammable gases
ISO 20560-1 & -2 Safety information for piping systems
International Standard ISO 20560-1:2020 Safety information for the content of piping systems and tanks — Part 1: Piping systems was intended to replace the variety of regulations and standards across countries and regions. Basic identification colours and warning symbols identify the pipe contents and any hazards.
Pipe markers consists of 4 basic elements:
Basic identification (background) colour, see table below, e.g. yellow for hazardous substance
Name of the substance/content, e.g. NATURAL GAS
Flow direction indicator arrows, ⇒
Warning symbols, e.g. GHS symbol
Colours and substances are typically as follows:
International Standard ISO 20560-2 Safety information for the content of piping systems and tanks — Part 2: Tanks, provides a similar colour scheme for tanks.
European standards: RAL Colours
RAL colour standard charts are used by architects, construction industry and road safety.
The pipe identification colours are as shown in the table.
See also
Piping
American National Standards Institute
American Society of Mechanical Engineers
Notes
References
Piping
Civil engineering
Hazardous materials
Chemical safety
Color codes | Pipe marking | [
"Physics",
"Chemistry",
"Technology",
"Engineering"
] | 1,281 | [
"Chemical accident",
"Building engineering",
"Chemical engineering",
"Construction",
"Materials",
"Civil engineering",
"nan",
"Mechanical engineering",
"Piping",
"Chemical safety",
"Hazardous materials",
"Matter"
] |
47,770,720 | https://en.wikipedia.org/wiki/List%20of%20nematode%20families | List of Nematoda has 25,000 recorded species from the Nematode phylum. There are estimated to be a million.
Class Chromadorea
Subclass Chromadoria
Order Araeolaimida
Superfamily Axonolaimoidea Filipjev, 1918
Axonolaimidae Filipjev, 1918
Bodonematidae Jensen, 1991
Comesomatidae Filipjev, 1918
Coninckiidae Lorenzen, 1981
Diplopeltidae Filipjev, 1918
Order Ascaridida
Order Chromadorida
Suborder Chromadorina
Superfamily Chromadoroidea Filipjev, 1917
Achromadoridae Gerlach & Riemann, 1973
Chromadoridae Filipjev, 1917
Cyatholaimidae Filipjev, 1918
Ethmolaimidae Filipjev & Schuurmans Stekhoven, 1941
Neotonchidae Wieser & Hopper, 1966
Selachinematidae Cobb, 1915
Order Desmodorida
Suborder Desmodorina
Superfamily Desmodoroidea Filipjev, 1922
Desmodoridae Filipjev, 1922
Draconematidae Filipjev, 1918
Epsilonematidae Steiner, 1927
Superfamily Microlaimoidea Micoletzky, 1922
Aponchiidae Gerlach, 1963
Microlaimidae Micoletzky, 1922
Monoposthiidae Filipjev, 1934
Order Desmoscolecida
Suborder Desmoscolecina
Superfamily Desmoscolecoidea Shipley, 1896
Cyartonematidae Tchesunov, 1990
Desmoscolecidae Shipley, 1896
†Eophasmidae Poinar, 2011
Meyliidae de Coninck, 1965
Order Monhysterida
Suborder Linhomoeina
Superfamily Siphonolaimoidea Filipjev, 1918
Fusivermidae Tchesunov, 1996
Linhomoeidae Filipjev, 1922
Siphonolaimidae Filipjev, 1918
Suborder Monhysterina
Superfamily Monhysteroidea Filipjev, 1929
Monhysteridae de Man, 1876
Superfamily Sphaerolaimoidea Filipjev, 1918
Sphaerolaimidae Filipjev, 1918
Xyalidae Chitwood, 1951
Order Plectida
Suborder Ceramonematina
Superfamily Ceramonematoidea Cobb, 1933
Ceramonematidae Cobb, 1933
Diplopeltoididae Tchesunov, 1990
Paramicrolaimidae Lorenzen, 1981
Tarvaiidae Lorenzen, 1981
Tubolaimoididae Lorenzen, 1981
Incertae sedis
Superfamily Haliplectoidea Chitwood, 1951
Haliplectidae Chitwood, 1951
Aegialoalaimidae Lorenzen, 1981
Aulolaimidae Jairajpuri & Hopper, 1968
Suborder Plectina
Superfamily Camacolaimoidea Micoletzky, 1924
Camacolaimidae Micoletzky, 1924
Rhadinematidae Lorenzen, 1981
Superfamily Leptolaimoidea Örley, 1880
Aphanolaimidae Chitwood, 1936
Leptolaimidae Örley, 1880
Superfamily Ohridioidea (Andrassy, 1976)
Creagrocercidae Baylis, 1943
Ohridiidae Andrássy, 1976
Superfamily Plectoidea Örley, 1880
Chronogastridae Gagarin, 1975
Metateratocephalidae Eroshenko, 1973
Plectidae Örley, 1880
Order Rhabditida
Incertae sedis
Brevibuccidae Paramonov, 1956
Chambersiellidae Thorne, 1937
Teratocephalidae Andrassy, 1958
Suborder Myolaimina
Superfamily Myolaimoidea Andrassy, 1958
Myolaimidae Andrassy, 1958
Suborder Rhabditina
Infraorder Bunonematomorpha
Superfamily Bunonematoidea Micoletzky, 1922
Bunonematidae Micoletzky, 1922
Pterygorhabditidae Goodey, 1963
Infraorder Diplogasteromorpha
Superfamily Cylindrocorporoidea Goodey, 1939
Cylindrocorporidae Goodey, 1939
Superfamily Diplogasteroidea Micoletzky, 1922
Cephalobiidae Filipjev, 1934
Diplogasteridae Micoletzky, 1922
Diplogasteroididae Filipjev & Schuurmans Stekhoven, 1941
Mehdinematidae Farooqui, 1967
Neodiplogasteridae Paramonov, 1952
Pseudodiplogasteroididae Körner, 1954
Superfamily Odontopharyngoidea Micoletzky, 1922
Odontopharyngidae Micoletzky, 1922
Infraorder Rhabditomorpha
Incertae sedis
Agfidae Dougherty, 1955
Carabonematidae Stammer & Wachek, 1952
Superfamily Mesorhabditoidea Andrassy, 1976
Mesorhabditidae Andrassy, 1976
Peloderidae Andrassy, 1976
Superfamily Rhabditoidea Örley, 1880
Diploscapteridae Micoletzky, 1922
Rhabditidae Örley, 1880
Superfamily Strongyloidea Baird, 1853
Ancylostomatidae Looss, 1905
Diaphanocephalidae Travassos, 1920
Heligmosomidae Cram, 1927
Heterorhabditidae Poinar, 1976
Metastrongylidae Diesing, 1851
Moleinidae Durette-Desset & Chabaud, 1977
Strongylidae Baird, 1853
Trichostrongylidae Leiper, 1912
Suborder Spirurina
Infraorder Ascaridomorpha
Superfamily Ascaridoidea Baird, 1853
Acanthocheilidae Wülker, 1929
Anisakidae Railliet & Henry, 1912
Ascarididae Baird, 1853
Heterocheilidae Railliet & Henry, 1915
Raphidascarididae Hartwich, 1954
Superfamily Cosmocercoidea Travassos, 1925
Atractidae Travassos, 1919
Cosmocercidae Travassos, 1925
Kathlaniidae Travassos, 1918
Superfamily Heterakoidea Railliet & Henry, 1912
Ascaridiidae Travassos, 1919
Aspidoderidae Skrjabin & Shikhobalova, 1947
Heterakidae Railliet & Henry, 1912
Superfamily Seuratoidea Railliet, 1906
Chitwoodchabaudiidae Puylaert, 1970
Cucullanidae Cobbold, 1864
Quimperiidae Gendre, 1928
Schneidernematidae Freitas, 1956
Seuratidae Railliet, 1906
Superfamily Subuluroidea Yorke & Maplestone, 1926
Maupasinidae Inglis, 1959
Subuluridae Yorke & Maplestone, 1926
Infraorder Gnathostomatomorpha
Superfamily Gnathostomatoidea Railliet, 1895
Gnathostomatidae Railliet, 1895
Incertae sedis
Superfamily Dracunculoidea Stiles, 1907
Anguillicolidae Yamaguti, 1935
Daniconematidae Moravec & Køie, 1987
Dracunculidae Stiles, 1907
Guyanemidae Petter, 1975
Micropleuridae Baylis & Daubney, 1926
Philometridae Baylis & Daubney, 1926
Skrjabillanidae Shigin & Shigina, 1958
Infraorder Oxyuridomorpha
Superfamily Oxyuroidea Cobbold, 1864
Heteroxynematidae Skrjabin & Shikhobalova, 1948
Oxyuridae Cobbold, 1864
Pharyngodonidae Travassos, 1919
Superfamily Thelastomatoidea Travassos, 1929
Hystrignathidae Travassos, 1929
Protrelloididae Chitwood, 1932
Thelastomatidae Travassos, 1929
Travassosinematidae Rao, 1958
Infraorder Rhigonematomorpha
Superfamily Ransomnematoidea Travassos, 1930
Camoyidae Travassos & Kloss, 1960
Hethidae Travassos & Kloss, 1960
Ransomnematidae Travassos, 1930
Superfamily Rhigonematoidea Artigas, 1930
Ichthyocephalidae Travassos & Kloss, 1958
Rhigonematidae Artigas, 1930
Infraorder Spiruromorpha
Superfamily Acuarioidea Railliet, Henry & Sisoff, 1912
Acuariidae Railliet, Henry & Sisoff, 1912
Superfamily Aproctoidea Skrjabin & Shikhobalova, 1945
Aproctidae Skrjabin & Shikhobalova, 1945
Desmidocercidae Cram, 1927
Superfamily Camallanoidea Travassos, 1920
Camallanidae Railliet & Henry, 1915
Superfamily Diplotriaenoidea Anderson, 1958
Diplotriaenidae Anderson, 1958
Oswaldofilariidae Chabaud & Choquet, 1953
Superfamily Filarioidea Chabaud & Anderson, 1959
Filariidae Chabaud & Anderson, 1959
Onchocercidae Leiper, 1911
Superfamily Habronematoidea Ivaschkin, 1961
Cystidicolidae Skrjabin, 1946
Habronematidae Ivaschkin, 1961
Hedruridae Railliet, 1916
Tetrameridae Travassos, 1914
Superfamily Physalopteroidea Railliet, 1893
Physalopteridae Railliet, 1893
Superfamily Rictularoidea Railliet, 1916
Rictulariidae Railliet, 1916
Superfamily Spiruroidea Oerley, 1885
Gongylonematidae Sobolev, 1949
Hartertiidae Quentin, 1970
Spirocercidae Chitwood & Wehr, 1932
Spiruridae Oerley, 1885
Superfamily Thelazioidea Skrjabin, 1915
Pneumospiruridae Wu & Hu, 1938
Rhabdochonidae Skrjabin, 1946
Thelaziidae Skrjabin, 1915
Suborder Tylenchina
Infraorder Cephalobomorpha
Superfamily Cephaloboidea Filipjev, 1934
Alirhabditidae Suryawanshi, 1971
Bicirronematidae Andrassy, 1978
Cephalobidae Filipjev, 1934
Elaphonematidae Heyns, 1962
Osstellidae Heyns, 1962
Infraorder Drilonematomorpha
Superfamily Drilonematoidea Pierantoni, 1916
Drilonematidae Pierantoni, 1916
Homungellidae Timm, 1966
Pharyngonematidae Chitwood, 1950
Ungellidae Chitwood, 1950
Incertae sedis
Superfamily Anguinoidea Nicoll, 1935
Infraorder Panagrolaimomorpha
Superfamily Panagrolaimoidea Thorne, 1937
Panagrolaimidae Thorne, 1937
Superfamily Strongyloidoidea Chitwood & McIntosh, 1934
Alloionematidae Chitwood & McIntosh, 1934
Rhabdiasidae Railliet, 1916
Steinernematidae Filipjev, 1934
Strongyloididae Chitwood & McIntosh, 1934
Infraorder Tylenchomorpha
Superfamily Aphelenchoidea Fuchs, 1937
Aphelenchidae Fuchs, 1937
Aphelenchoididae Skarbilovich, 1947
Superfamily Criconematoidea Taylor, 1936
Criconematidae Taylor, 1936
Hemicycliophoridae Skarbilovich, 1959
Tylenchulidae Skarbilovich, 1947
Superfamily Myenchoidea Pereira, 1931
Myenchidae Pereira, 1931
Superfamily Sphaerularioidea Lubbock, 1861
Anguinidae Nicoll, 1935
Iotonchidae Goodey, 1935
Neotylenchidae Thorne, 1941
Sphaerulariidae Lubbock, 1861
Superfamily Tylenchoidea Örley, 1880
Belonolaimidae Whitehead, 1959
Dolichodoridae Chitwood, 1950
Hoplolaimidae Filipjev, 1934
Meloidogynidae Skarbilovich, 1959
Pratylenchidae Thorne, 1949
Tylenchidae Örley, 1880
Order Spirurida
Suborder Camallanina
Order Strongylida
Superfamily Metastrongyloidea Lane, 1917
Pseudaliidae Railliet & Henry, 1909
Superfamily Trichostrongyloidea (Durette-Desset, 1985)
Amidostomatidae Baylis & Daubney, 1926
Class Enoplea
Subclass Dorylaimia
Order Dioctophymatida
Suborder Dioctophymatina
Dioctophymidae Railliet, 1915
Soboliphymatidae Petrov, 1930
Order Dorylaimida
Suborder Dorylaimina
Superfamily Belondiroidea Thorne, 1964
Belondiridae Thorne, 1939
Superfamily Dorylaimoidea de Man, 1876
Actinolaimidae Thorne, 1939
Aporcelaimidae Heyns, 1965
Dorylaimidae de Man, 1876
Longidoridae Thorne, 1935
Nordiidae Jairajpuri & Siddiqi, 1964
Qudsianematidae Jairajpuri, 1965
Incertae sedis
Thornenematidae Siddiqi, 1969
Thorniidae de Coninck, 1965
Superfamily Tylencholaimoidea Filipjev, 1934
Aulolaimoididae Jairajpuri, 1964
Leptonchidae Thorne, 1935
Mydonomidae Thorne, 1964
Tylencholaimellidae Jairajpuri, 1964
Tylencholaimidae Filipjev, 1934
Suborder Nygolaimina
Superfamily Nygolaimoidea Thorne, 1935
Aetholaimidae Jairajpuri, 1965
Nygellidae Andrassy, 1958
Nygolaimellidae Clark, 1961
Nygolaimidae Thorne, 1935
Order Isolaimida
Superfamily Isolaimoidea Timm, 1969
Isolaimiidae Cobb, 1920
Order Marimermithida
Marimermithidae Rubtzov & Platonova, 1974
Order Mermithida
Suborder Mermithina
Superfamily Mermithoidea Braun, 1883
Mermithidae Braun, 1883
Tetradonematidae Cobb, 1919
Order Mononchida
Suborder Bathyodontina
Superfamily Cryptonchoidea Chitwood, 1937
Bathyodontidae Clark, 1961
Cryptonchidae Chitwood, 1937
Superfamily Mononchuloidea de Coninck, 1965
Mononchulidae de Coninck, 1965
Suborder Mononchina
Superfamily Anatonchoidea Jairajpuri, 1969
Anatonchidae Jairajpuri, 1969
Incertae sedis
Cobbonchidae Jairajpuri, 1969
Iotonchidae Jairajpuri, 1969
Superfamily Mononchoidea Filipjev, 1934
Mononchidae Filipjev, 1934
Mylonchulidae Jairajpuri, 1969
Order Muspiceida
Suborder Muspiceina
Muspiceidae Bain & Chabaud, 1959
Robertdollfusiidae Chabaud & Campana, 1950
Order Trichinellida
Superfamily Trichinelloidea Ward, 1907
Anatrichosomatidae Yamaguti, 1961
Capillariidae Railliet, 1915
Cystoopsidae Skrjabin, 1923
Trichinellidae Ward, 1907
Trichosomoididae Yorke & Maplestone, 1926
Trichuridae Railliet, 1915
Subclass Enoplia
Order Enoplida
Suborder Alaimina
Superfamily Alaimoidea Micoletzky, 1922
Alaimidae Micoletzky, 1922
Suborder Campydorina
Superfamily Campydoroidea Jairajpuri, 1976
Campydoridae (Thorne, 1935)
Suborder Dioctophymina
Suborder Enoplina
Superfamily Enoploidea Dujardin, 1845
Anoplostomatidae Gerlach & Riemann, 1974
Anticomidae Filipjev, 1918
Enoplidae Dujardin, 1845
Phanodermatidae Filipjev, 1927
Thoracostomopsidae Filipjev, 1927
Incertae sedis
Andrassyidae Tchesunov & Gagarin, 1999
Suborder Ironina
Superfamily Ironoidea de Man, 1876
Ironidae de Man, 1876
Leptosomatidae Filipjev, 1916
Oxystominidae Chitwood, 1935
Suborder Oncholaimina
Superfamily Oncholaimoidea Filipjev, 1916
Enchelidiidae Filipjev, 1918
Oncholaimidae Filipjev, 1916
Thalassogeneridae Orton Williams & Jairajpuri, 1984
Suborder Trefusiina
Superfamily Trefusioidea Gerlach, 1966
Lauratonematidae Gerlach, 1953
Simpliconematidae Blome & Schrage, 1985
Trefusiidae Gerlach, 1966
Trischistomatidae Andrassy, 2007
Xenellidae de Coninck, 1965
Suborder Trichinellina
Suborder Tripyloidina
Superfamily Tripyloidoidea Filipjev, 1928
Tripyloididae Filipjev, 1918
Order Triplonchida
Suborder Diphtherophorina
Superfamily Diphtherophoroidea Micoletzkyi, 1922
Diphtherophoridae Micoletzky, 1922
Trichodoridae Thorne, 1935
Incertae sedis
Bastianiidae de Coninck, 1965
Odontolaimidae Gerlach & Riemann, 1974
Suborder Tobrilina
Superfamily Prismatolaimoidea Micoletzky, 1922
Prismatolaimidae Micoletzky, 1922
Superfamily Tobriloidea Filipjev, 1918
Pandolaimidae Belogurov, 1980
Rhabdodemaniidae Filipjev, 1934
Tobrilidae de Coninck, 1965
Triodontolaimidae de Coninck, 1965
Suborder Tripylina
Superfamily Tripyloidea de Man, 1876
Tripyloidea de Man, 1876
Tripylidae de Man, 1876
Incertae sedis
Order Benthimermithida
Benthimermithidae Petter, 1980
Order Rhaptothyreida
Rhaptothyreidae Hope & Murphy, 1969
Class Secernentea
Order Camallanida (sometimes included in Spirurida)
Family Anguillicolidae
Family Camallanidae
Family Dracunculidae
Family Micropleudidae
Family Philometridae
Order Drilonematida (sometimes included in Spirurida)
Order Oxyurida (= Rhabdiasida)
Family Heteroxynematidae
Family Oxyuridae
Family Pharyngodonidae
Family Thelastomatidae
Order Rhigonematida (formerly in Tylenchia)
Order Spirurida
Superfamily Acuarioidea
Superfamily Aproctoidea
Superfamily Diplotriaenoidea
Superfamily Filarioidea
Superfamily Gnathostomatoidea
Superfamily Habronematoidea
Superfamily Physalopteroidea
Superfamily Rictularioidea
Superfamily Spiruroidea
Superfamily Thelazioidea
Subclass Diplogasteria
(may belong in Rhabditia)
Order Diplogasterida
Suborder Chambersiellina Hodda 2007
Superfamily Chambersielloidea Thorne 1937
Family Chambersiellidae Thorne 1937 (Sanwal 1957)
Suborder Diplogasterina Paramonov 1952
Superfamily Cylindrocorporoidea T. Goodey 1939
Family Cylindrocorporidae T. Goodey 1939
Family Odontopharyngidae Micoletzky 1922
Superfamily Diplogasteroidea Micoletzky 1922
Family Cephalobiidae Travassos & Kloss 1960a
Family Diplogasteridae Micoletzky 1922
Family Diplogasteroididae Paramonov 1952
Family Neodiplogasteridae Paramonov 1952
Family Pseudodiplogasteroididae De Ley & Blaxter 2002
Family Tylopharyngidae Filipjev 1918
Suborder Myolaimina Inglis 1983
Superfamily Carabonematoidea Stammer & Wachek 1952
Family Carabonematidae Stammer & Wachek 1952
Superfamily Myolaimoidea Goodey 1963
Family Myolaimidae Goodey 1963
Subclass Tylenchia
(may belong in Rhabditia)
Order Aphelenchida
Family Aphelenchidae
Family Aphelenchoididae
Family Myenchildae
Family Paraphelenchidae
Order Tylenchida
Superfamily Criconematoidea
Family Criconematidae
Family Tylenchulidae
Superfamily Tylenchoidea
Family Anguinidae
Family Belonolaimidae
Family Dolichodoridae
Family Ecphyadophoridae
Family Hoplolaimidae
Family Heteroderidae
Family Pratylenchidae
Family Tylenchidae
Superfamily Sphaerularina
Family Allantonematidae
Family Fergusobiidae
Family Iotonchiidae
Family Parasitylenchidae
Family Sphaerulariidae
See also
List of nematodes in Sabah
References
List of
Nematode
Nematoda | List of nematode families | [
"Biology"
] | 4,413 | [
"Lists of biota",
"Lists of animals",
"Animals"
] |
47,771,051 | https://en.wikipedia.org/wiki/Penicillium%20subspinulosum | Penicillium subspinulosum is a species of fungus in the genus Penicillium which was isolated from soil in Poland.
References
subspinulosum
Fungi described in 2014
Fungus species | Penicillium subspinulosum | [
"Biology"
] | 41 | [
"Fungi",
"Fungus species"
] |
47,771,159 | https://en.wikipedia.org/wiki/International%20Workshop%20on%20Operator%20Theory%20and%20its%20Applications | International Workshop on Operator Theory and its Applications (IWOTA) was started in 1981 to bring together mathematicians and engineers working in operator theoretic side of functional analysis and its applications to related fields. These include:
Differential equations and Integral equations
Complex analysis and Harmonic analysis
Linear system and Control theory
Mathematical physics
Signal processing
Numerical analysis
The other major branch of operator theory, Operator algebras (C* and von Neumann Algebras), is not heavily represented at IWOTA and has its own conferences.
IWOTA gathers leading experts from all over the world for an intense exchange of new results, information and opinions, and for tracing the future developments in the field. The IWOTA meetings provide opportunities for participants (including young researchers) to present their own work in invited and contributed talks, to interact with other researchers from around the globe, and to broaden their knowledge of the field.
In addition, IWOTA emphasizes cross-disciplinary interaction among mathematicians, electrical engineers and mathematical physicists. In the even years, the IWOTA workshop is a satellite meeting to the biennial International Symposium on the Mathematical Theory of Networks and Systems (MTNS). From the humble beginnings in the early 80's, the IWOTA workshops grew to become one of the largest continuing conferences attended by the community of researchers in operator theory.
History of IWOTA
First IWOTA Meeting
The International Workshop on Operator Theory and its Applications was started on August 1, 1981, adjacent to the International Symposium on Mathematical Theory of Networks and Systems (MTNS) with goal of exposing operator theorists, even pure theorists, to recent developments in engineering (especially H-infinity methods in control theory) which had a significant intersection with operator theory. Israel Gohberg was the visionary and driving force of IWOTA and president of the IWOTA Steering Committee. From the beginning, J. W. Helton and M. A. Kaashoek served as vice presidents of the steering committee.
West Meets East
Besides the excitement of mathematical discovery over the decades at IWOTA, there was great excitement when the curtain between Soviet bloc and Western operator theorists fell. Until 1990, these two collections of extremely strong mathematicians seldom met due to the tight restrictions on travel from and in the communist countries. When the curtain dropped, the western mathematicians knew the classic Soviet papers but had a spotty knowledge of much of what else their counterparts were doing. Gohberg was one of the operator theorists who knew both sides and he guided IWOTA, a western institution, in bringing (and funding) many prominent FSU bloc operator theorists to speak at the meetings. As the IWOTA programs demonstrate, this significantly accelerated the cultures' mutual assimilation.
Previous IWOTA Meetings
IWOTA Proceedings
Proceedings of the IWOTA workshops appear in the Springer / Birkhäuser Verlag book series Operator Theory: Advances and Applications (OTAA) (founder: Israel Gohberg). While engineering conference proceedings often are handed to participants as they arrive and contain short papers on each conference talk, the IWOTA proceedings follow mathematics conference tradition and contain a modest number of papers and are published several years after the conference.
Funding Sources
IWOTA has received support from many sources, including the National Science Foundation
, the London Mathematical Society, the Engineering and Physical Sciences Research Council, Deutsche Forschungsgemeinschaft, Secretaría de Estado de Investigación, Desarrollo e Innovación (Spain), Australian Mathematical Sciences Institute, National Board for Higher Mathematics, International Centre for Theoretical Physics, Indian Statistical Institute, Korea Research Foundation, United States-India Science & Technology Endowment Fund, Nederlandse Organisatie voor Wetenschappelijk Onderzoek, the Commission for Developing Countries of the International Mathematical Union, Stichting Advancement of Mathematics (Netherlands), the National Research Foundation of South Africa, and Birkhäuser Publishing Ltd.
The IWOTA Steering Committee
IWOTA is directed by a steering committee which chooses the site for the next meeting, elects the chief local organizer(s) and insures the appearance of the enduring themes of IWOTA. The sub-themes of an IWOTA workshop and the lecturers are chosen by the local organizing committee after hearing the steering committee's board. The board consists of its vice presidents: Joseph A. Ball, J. William Helton (Chair), Sanne ter Horst, Igor Klep, Christiane Tretter, Irene Sabadini, Victor Vinnikov and Hugo J. Woerdeman. In addition, past chief organizers who remain active in IWOTA are members of the steering committee. The board governs IWOTA with consultation and the consent of the full steering committee. Honorary members of the steering committee, elected in 2016, are: Israel Gohberg (deceased in 2009), Leiba Rodman (deceased in 2015), Tsuyoshi Ando, Harry Dym (deceased in 2024), Ciprian Foiaş (deceased in 2020), Heinz Langer (deceased in 2024), Nikolai Nikolski. Honorary member of the steering committee, elected in 2024, is: Rien Kaashoek.
Future IWOTA Meetings
IWOTA 2025 will be held at University of Twente in Enschede, The Netherlands. Main organizer is Felix Schwenninger. Dates are July 14-18, 2025
IWOTA 2026 will be held at Université Laval in Quebec City, Canada. Main organizers are Javad Mashreghi and Frédéric Morneau-Guérin. Dates are August 3-7, 2026
Israel Gohberg ILAS-IWOTA Lecture
The Israel Gohberg ILAS-IWOTA Lecture was introduced in August 2016 and honors the legacy of Israel Gohberg, whose research crossed borders between operator theory, linear algebra, and related fields. This lecture is in collaboration with the International Linear Algebra Society (ILAS). This series of lectures will be delivered at IWOTA and ILAS Conferences, in different years, in the approximate ratio two-thirds at IWOTA and one-third at ILAS. The first three lectures will take place at IWOTA Lancaster UK 2021, ILAS 2022, and IWOTA 2024. Donations for the Israel Gohberg ILAS-IWOTA Lecture Fund are most welcome and can be submitted via the ILAS donation form. Donations are tax deductible in the United States.
References
External links
Operator Theory: Advances and Applications Series on Springer website
IWOTA's YouTube Channel
IWOTA 2000 - Bordeaux, France
IWOTA 2006 - Seoul, Korea
IWOTA 2007 - Potchefstroom, South Africa
IWOTA 2008 - Williamsburg, Virginia, U.S.A
IWOTA 2010 - Berlin, Germany
IWOTA 2011 - Seville, Spain
IWOTA 2012 - Sydney, Australia
IWOTA 2013 - Bangalore, India
IWOTA 2014 - Amsterdam, Netherlands
IWOTA 2015 - Tbilisi, Georgia
IWOTA 2016 - St. Louis, Missouri, USA
IWOTA 2017 - Chemnitz, Germany
IWOTA 2019 - Lisbon, Portugal
IWOTA Chapman USA 2021 - Orange, California, USA
IWOTA Lancaster UK 2021 - Lancaster, United Kingdom
IWOTA 2022 - Kraków, Poland
IWOTA 2023 - Helsinki, Finland
IWOTA 2024 - Canterbury, United Kingdom
IWOTA 2025 - Enschede, The Netherlands
Mathematics conferences
Operator theory
Functional analysis
Mathematical analysis
Mathematical societies
Organizations established in 1981 | International Workshop on Operator Theory and its Applications | [
"Mathematics"
] | 1,539 | [
"Mathematical analysis",
"Functions and mappings",
"Functional analysis",
"Mathematical objects",
"Mathematical relations"
] |
47,771,356 | https://en.wikipedia.org/wiki/Hannele%20Ruohola-Baker | Hannele Ruohola-Baker (born December 10, 1959) is a Professor of Biochemistry and Associate Director of the Institute for Stem Cell and Regenerative Medicine at the University of Washington in Seattle, Washington. Her research focuses on the molecular biology of stem cells and on the use of Drosophila (fruit flies) as model organisms for human diseases.
Early life and education
Ruohola-Baker was born in the small village of Kullaa, Finland in 1959. She received her bachelor's and master's degree from the University of Helsinki and received her Ph.D. in cell biology from Yale University in 1989, studying cellular transport and advised by Susan Ferro-Novick. She then moved to a visiting fellowship at the Ludwig Institute for Cancer Research at the Karolinska Institute in Stockholm and subsequently to a postdoctoral fellowship at the University of California, San Francisco with Yuh Nung and Lily Jan.
Academic career
Ruohola-Baker began her faculty career at the University of Washington in 1993 and became a full professor in 2004. She held a Pew Scholars grant from 1996-2000.
Research
Ruohola-Baker's research focuses on stem cells and the molecular requirements for differentiation, with particular interest in the role of microRNA and in the relationship between metabolism and epigenetic changes in different types of stem cells. The research group also has a long-standing interest in studying the Notch and S1P signaling pathway using Drosophila as models of human diseases, particularly Duchenne muscular dystrophy and cancer.
Personal life
Ruohola-Baker is married to fellow UW biochemist David Baker, who won the 2024 Nobel Prize in Chemistry.
External links
References
Living people
American women biochemists
Stem cell researchers
Finnish emigrants to the United States
University of Washington faculty
University of Helsinki alumni
1959 births
American women academics
21st-century American women | Hannele Ruohola-Baker | [
"Biology"
] | 382 | [
"Stem cell researchers",
"Stem cell research"
] |
47,771,602 | https://en.wikipedia.org/wiki/Hydnellum%20underwoodii | Hydnellum underwoodii is an inedible species of tooth fungus in the family Bankeraceae. Found in North America, it was described as new to science in 1906 by American mycologist Howard James Banker. Its reddish-brown, convex to flattened cap measures in diameter. Reddish-brown, partially erect scales adorn the cap surface. Spines on the cap underside are 1–3 mm long; they are initially white, becoming brown with grayish tips in age. The oval to spherical spores are 6–7.5 by 5.5–6.5 μm. The fungus fruits singly or scattered, on the ground in coniferous forests.
References
External links
Fungi described in 1906
Fungi of North America
Inedible fungi
underwoodii
Fungus species | Hydnellum underwoodii | [
"Biology"
] | 155 | [
"Fungi",
"Fungus species"
] |
47,771,946 | https://en.wikipedia.org/wiki/Penicillium%20subtile | Penicillium subtile is a species of fungus in the genus Penicillium.
References
subtile
Fungi described in 1841
Taxa named by Miles Joseph Berkeley
Fungus species | Penicillium subtile | [
"Biology"
] | 36 | [
"Fungi",
"Fungus species"
] |
47,772,193 | https://en.wikipedia.org/wiki/American%20Journal%20of%20Industrial%20Medicine | The American Journal of Industrial Medicine is a monthly peer-reviewed medical journal covering occupational safety and health, as well as environmental health. It was established in 1980 and is published by Wiley-Blackwell. The editor-in-chief is John Meyer, formerly Steven B. Markowitz (Queens College, City University of New York). According to the Journal Citation Reports, the journal has a 2014 impact factor of 1.737.
References
External links
Occupational safety and health journals
Environmental health journals
Monthly journals
Wiley-Blackwell academic journals
Academic journals established in 1980
English-language journals | American Journal of Industrial Medicine | [
"Environmental_science"
] | 114 | [
"Environmental science journals",
"Environmental health journals"
] |
47,772,287 | https://en.wikipedia.org/wiki/John%20H.%20Ebersole | Captain John Henry Ebersole, M.D., United States Navy Medical Corps (26 January 1925 – 23 September 1993) was a pioneer in submarine medicine and radiation oncology, selected by Admiral Hyman G. Rickover to serve as medical officer aboard the US Navy's first two nuclear powered submarines, the and the . He was the radiologist for NASA that screened the Mercury Seven astronauts for Project Mercury. Ebersole was the radiologist responsible for the x-rays taken during the autopsy of John F. Kennedy on 22 November 1963 at Bethesda Naval Medical Center.
Biography
Ebersole was born in 1925 at Sterling, Illinois. He grew up in northwestern Illinois.
Ebersole served for 24 years in the U.S. Navy Medical Corps. He was the first officer to serve aboard two nuclear submarines, the and the , being selected by Admiral Hyman G. Rickover as the medical officer for the crew. He worked with NASA on Project Mercury. Ebersole was assigned to Bethesda Naval Medical Center and was the radiologist for the autopsy of President John F. Kennedy. He was chief of radiation therapy, training director for nuclear medicine, and director of the Radiation Exposure Evaluation Laboratory. He became chief of diagnostic radiology and chief of radiology. After retirement from the Navy, Ebersole settled in Lancaster, Pennsylvania, where he established and directed the John Hale Steinman Cancer Center at Lancaster General Hospital. Upon retirement from medical practice, Ebersole pursue a lifelong passion in mystery novels and crime fiction. He traveled to England and attended conferences at Oxford University. He became adjunct faculty at Franklin and Marshall College and taught a detective fiction course in the EtCetera program. He was a founding member of the Orange Street Improbables, a group of mystery enthusiasts.
In 1993, Ebersole died at home after a brief illness at Lancaster, Pennsylvania. He was buried at Arlington National Cemetery, in plot: Sec: 8, Site: 9473.
Education
Ebersole completed his undergraduate studies at Saint Ambrose College in Davenport, Iowa. In 2013, he was posthumously inducted into the Newman Central Catholic High School Hall of Fame at Sterling, Illinois. He attended the Indiana University School of Medicine and graduated in 1948, receiving his M.D. at the age 23.
U.S. Navy career
Ebersole entered the U.S. Navy in July 1948 and trained in undersea medicine. As a future submarine doctor, Ebersole received extensive nuclear training. From 1949 to 1959, Ebersole was associated with nuclear submarines and had special training in nuclear physics at Duke University and at Oak Ridge, Tennessee. Ebersole was commissioned in the U.S. Navy and served on the USS Nautilus and the USS Seawolf, the first two nuclear submarines. Ebersole was selected by Admiral Hyman G. Rickover as the medical officer for the USS Nautilus, the first nuclear-powered submarine and served under commanding officer Commander Eugene Parks Wilkinson. Ebersole was a member of the launching crew for the USS Nautilus. He went on to serve as medical officer aboard the USS Seawolf, the second nuclear submarine for the U.S. Navy. Ebersole was the first person to serve on more than one nuclear powered vessel.
On 26 September 1957, President Dwight D. Eisenhower boarded the USS Seawolf at Narragansett Bay and was greeted by skipper Commander Richard B. Lanning and Rear Admiral Frederick B. Warder, Atlantic Fleet submarine force commander. The President was briefed by Ebersole regarding radiation exposure aboard the Seawolf.
According to The New York Times report:
The President was briefed about controlled radiation exposure aboard nuclear-powered submarines. He received a film patch to wear and a tiny dosimeter to read. The medical officer, Lieutenant Commander John E. Ebersole of Sterling, Illinois, explained to the President that submariners in the new type craft get an average radiation dosage of about 200 milliroentgens a year, compared with an allowable industrial dose of about 300 a week. As he left the boat, the President jokingly told Admiral Warder to check on his film patch and "let me know if I had too much radiation." "I assure you, you won't have," the Admiral said."
During his tour, the Seawolf set a new record of submergence for 60 days under the command of Captain Richard Boyer Laning. Captain Laning and the Seawolf crew were greeted upon return to port at New London, Connecticut, by Rear Admiral Hyman G. Rickover.
When the USS Seawolf was decommissioned, he started a residency in radiology at Bethesda Naval Hospital. In July 1963, he completed residency. He then became Chief of Radiation Therapy in the Medicine Section at Bethesda Naval Hospital.
Nuke School
Eventually, the Navy established a routine training program for what would be called Nuke School. The coursework for officers to be assigned to nuclear submarines and ships began at Reed College in Oregon with 24 weeks of training. Then they received 6 weeks of field training at the Atomic Energy Commission's Hanford plutonium production facilities in Washington. Next the candidates spent 5 weeks at the Nevada Test Site and the Sandia nuclear weapons laboratory in New Mexico. They finished up with 6 weeks of additional training at the Walter Reed Laboratory in Maryland.
NASA
From 1958 to 1961, Ebersole worked with NASA during the training phase of the Project Mercury. Ebersole was part of the committee that evaluated the candidates selected for Project Mercury, the NASA Special Committee on Life Sciences. The committee included: Dr. William Randolph Lovelace II, Captain Norman L. Barr, Lieutenant Commander John H. Ebersole, Brigadier General Donald D. Flickinger, LtCol Robert H. Holmes, Dr. Wright Haskell Langham, Dr. Robert Burr Livingston, Dr. Orr Reynolds, and Boyd C. Myers II, committee secretary.
John F. Kennedy autopsy
At the time of the President Kennedy autopsy, Ebersole was Commander, United States Navy, Assistant Chief of Radiology and head of the Radiology Division at Bethesda Naval Medical Center. Ebersole was the radiologist responsible for the x-rays taken during the autopsy of John F. Kennedy on 22 November 1963 at Bethesda Naval Medical Center. After the assassination of John F. Kennedy, Ebersole remained at Bethesda Naval Medical Center. In 1968, he was promoted to chairman of the radiology department and retired in 1970.
Personal life
On 21 October 1948, John H. Ebersole, physician applied for a marriage license to wed Marion E. Sherwood, nurse. The couple were married on 30 October 1948 at St. Vincent de Paul church by Reverend M.J. Rouck in Bedford, Indiana. Ebersole was the son of Noah Ebersole, auto mechanic and Geraldine Kathryn McCormick, housewife. Marion was the daughter of Samuel J. Sherwood, estimator and Maybelle Elizabeth Lehay.
Professional Service
American Medical Association, member
Society of Nuclear Medicine, member
Health Physics Society, member
Association of Military Surgeons of the United States, member
American College of Radiology, diplomat and fellow
American Board of Radiology, guest examiner, 1967, 1970- 1971.
Illinois State Medical Society, Award of Merit, 1959
Awards and honors
U.S. Navy Presidential Unit Citation - USS Nautilus SSN-571
U.S. Navy Unit Commendation - USS Seawolf SSN-575
Royal Naval Society of Sweden, Merit Citation
Gorgas Medal, 1958. "Ebersole, Medical Officer of the Seawolf, record-breaking atomic submarine, received the Gorgas Medal, scroll, and $500 for outstanding service in radiation protection of the crew. He received the award for outstanding work in preventive medicine in the field of radiobiology and nuclear submarine development."
Publications
Ebersole, J. H. (1952). Submarine atomic defense. Report 215. AD 224406. Naval Submarine Medical Research Laboratory. Groton, Connecticut.
Ebersole, John H. (1957). Radiation Hygiene: Aboard Nuclear Submarines. American Industrial Hygiene Association Quarterly. 18(4): pages 305-311.
Ebersole, J. H. (1957). Radiation exposure patterns aboard the USS Nautilus. New England Journal of Medicine. 256(2): pages 67-74.
Ebersole, J. H. (1958). Submarine medicine on USS Nautilus and USS Seawolf. Proceedings of the Royal Society of Medicine. 51(2): page 63.
Ebersole, J. H. (1959). Occupational health problems in space flight as experienced with nuclear power plants. Military Medicine. 124: pages 711-716.
Ebersole, J. H. (1960). The new dimensions of submarine medicine. New England Journal of Medicine. 262: pages 599-610.
Bottomley, William K., & Ebersole, J. H. (1966). Guidelines for dental care when patients receive radiation therapy to the head and neck. Oral Surgery, Oral Medicine, Oral Pathology. 22(2): pages 252-256.
Royster, R. L., King, E. R., Ebersole, J., DeGiorgi, L. S., & Levitt, S. H. (1972). High dose, preoperative supervoltage irradiation for osteogenic sarcoma. American Journal of Roentgenology. 114(3): pages 536-543.
References
1925 births
1993 deaths
American radiologists
People from Sterling, Illinois
Military personnel from Illinois
St. Ambrose University alumni
Indiana University School of Medicine alumni
Health Physics Society
Health physicists
Assassination of John F. Kennedy
United States Navy captains
United States Navy submariners
Kennedy administration personnel
Project Mercury
NASA people
People from Lancaster, Pennsylvania
+
Oak Ridge National Laboratory people
Duke University alumni
Dwight D. Eisenhower
Radiation health effects researchers
Radiation protection
Radiation health effects
Burials at Arlington National Cemetery
Submarines of the United States Navy
People from Bethesda, Maryland
Walter Reed Army Medical Center
United States Navy Medical Corps officers
Franklin & Marshall College alumni | John H. Ebersole | [
"Chemistry",
"Materials_science"
] | 2,089 | [
"Radiation effects",
"Radiation health effects",
"Radioactivity"
] |
47,772,789 | https://en.wikipedia.org/wiki/Biotin%20hydrazide | Biotin hydrazide is a biotinyl derivative that can be used as a probe for the determination of protein carbonylation. It readily forms Schiff bases with carbonyl groups.
References
Reagents for biochemistry
Hydrazides | Biotin hydrazide | [
"Chemistry",
"Biology"
] | 49 | [
"Biochemistry methods",
"Organic compounds",
"Biochemistry",
"Reagents for biochemistry",
"Organic compound stubs",
"Organic chemistry stubs"
] |
47,772,816 | https://en.wikipedia.org/wiki/4-Oxo-2-nonenal | 4-Oxo-2-nonenal is a lipid peroxidation product that can structurally alter proteins and induce α-synuclein oligomers.
References
Conjugated aldehydes | 4-Oxo-2-nonenal | [
"Chemistry"
] | 44 | [
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
47,773,999 | https://en.wikipedia.org/wiki/Adeyinka%20Afolayan | Adeyinka Afolayan is a Nigerian Professor of Biochemistry and fellow of the Nigerian Academy of Science, elected into the Academy's Fellowship at its annual general meeting held in 2006.
References
Year of birth missing (living people)
Living people
Nigerian chemists
Biochemists | Adeyinka Afolayan | [
"Chemistry",
"Biology"
] | 57 | [
"Biochemistry",
"Biochemists"
] |
47,775,359 | https://en.wikipedia.org/wiki/Multiple%20hearth%20furnace | A multiple hearth furnace also known as a vertical calciner, is used for continuous preparation and calcining of materials.
Working
The multiple hearth furnaces consist of several circular hearths or kilns superimposed on each other. Material is fed from the top and is moved by the action of rotating "rabble arms", and the revolving mechanical rabbles attached to the arms move over the surface of each hearth to continuously shift the ore. The arms are attached to a rotating central shaft that passes through the center of the roaster. As the material is moved, the ore that is charged at the top hearth gradually moves downward as it passes through windows in the floor of each hearth or through alternate passages around the shaft and the periphery until it finally emerges at the bottom.
Gas
The oxidizing gases flow upward, i.e., counter-current to the descending charge. In a well-insulated roaster, external heating is unnecessary except when the charge is highly moist. The hearth at the top of the roaster dries and heats the charge. Ignition and oxidation of the charge occur lower down.
Variables
The hearths may be individually heated and the number, temperature, rotation rate, and size of each hearth determine the residence time and conditions for the calcining powder in order to achieve the desired final properties.
Structure of furnace
The individual hearths are lined with refractory brick, and the rabble arms are typically a force-cooled metal alloy. The entire structure is enclosed in a cylindrical brick-lined steel shell.
References
Smelting
Metallurgical processes | Multiple hearth furnace | [
"Chemistry",
"Materials_science"
] | 324 | [
"Metallurgical processes",
"Metallurgy",
"Smelting"
] |
47,775,741 | https://en.wikipedia.org/wiki/Rule-based%20DFM%20analysis%20for%20electric%20discharge%20machining | Electrical discharge machining (or EDM) is one of the most accurate manufacturing processes available for creating complex or simple shapes and geometries within parts and assemblies. A machining method typically used for hard metals, EDM makes it possible to work with metals for which traditional machining techniques are ineffective.
Design for manufacturability (also sometimes known as design for manufacturing or DFM) is the general engineering art of designing products in such a way that they are easy to manufacture. The concept exists in almost all engineering disciplines, but the implementation differs widely depending on the manufacturing technology. DFM describes the process of designing or engineering a product in order to facilitate the manufacturing process in order to reduce its manufacturing costs. DFM will allow potential problems to be fixed in the design phase which is the least expensive place to address them. Other factors may affect the manufacturability such as the type of raw material, the form of the raw material, dimensional tolerances, and secondary processing such as finishing.
Depending on various types of manufacturing processes there are set guidelines for DFM practices. These DFM guidelines help to precisely define various tolerances, rules and common manufacturing checks related to DFM. Rule based guidelines which can be referred to while designing parts are mentioned below. The parts are designed considering manufacturability with electrical discharge machining in mind.
Mechanical design considerations
Minimum internal corner radius
The minimum internal corner radius of the feature will dictate the maximum wire diameter that can be used. The wire diameter needs to be less than double the minimum internal corner radius for successful machining. However, the amount of final overcut and a small amount of maneuvering need to be taken into account for the corner to be generated. For small diameter wires, the following are recommended:
Surface finishing
Surface finishing comprises the small local deviations of a surface from the perfectly flat ideal. It is one of the important factors that controls friction and transfer layer formation during sliding.
Many wire EDM machines have adopted the pulse generating circuit using low power for ignition and high power for machining. However, it is not suitable for finishing process since the energy generated by the high voltage sub-circuit is too high to obtain a desired fine surface. Relaxing the surface finish allows the manufacturer to produce the part with fewer passes, at a higher current level and a higher metal-removal rate, enabling lower production time and cost.
Material removal
The removal of material in EDM is associated with the erosive effects produced when discrete and spatial discharge occurs between the tool and work-piece electrodes. Short duration sparks generated between these two electrodes. The generator releases electrical energy, which is responsible for melting a small quantity of material from both the electrodes. The part should be designed and prepared such that the amount of stock removed by EDM is relatively small. Traditional machining techniques, such as milling can be used to remove bulk of stock with the finishing operations performed by EDM.
Simultaneous machining
EDM enhanced with CNC systems is a highly competitive model for making forging dies, casting tooling, plastic injection molds and tooling for powder metals. It enables the user to machine simultaneously multiple highly precise parts from a single clamping. Designs should be considered such that several parts can be stacked and machined simultaneously or a single part can have several EDM operations performed simultaneously.
Enlarging holes
When existing holes are to be enlarged or reshaped by EDM, through holes are preferred to blind holes as they permit easier flow of dielectric fluid past the area being machined.
Sharp corners
When cutting sharp corners, the wire dwells longer by the inside radius causing a slight overcut. On the outside radius, it speeds, leaving a slight undercut. Hence, sharp corners should be avoided while designing part.
Galvanic corrosion
Galvanic corrosion is an electrochemical process in which one metal corrodes preferentially to another when both metals are in electrical contact, in the presence of an electrolyte. In EDM, there will be some degree of material exchange between the wire or the probe and the base material. Electrodes and base material should be chosen to prevent galvanic corrosion as far as possible.
References
Machining
Manufacturing | Rule-based DFM analysis for electric discharge machining | [
"Engineering"
] | 858 | [
"Manufacturing",
"Mechanical engineering"
] |
47,776,323 | https://en.wikipedia.org/wiki/Phellodon%20confluens | Phellodon confluens, commonly known as the fused cork hydnum, is a species of tooth fungus in the family Bankeraceae. It was originally described in 1825 as Hydnum confluens by Christiaan Hendrik Persoon. Czech mycologist Zdenek Pouzar transferred it to the genus Phellodon in 1956. The fungus is found in Asia, Europe, and North America. It is considered vulnerable in Switzerland.
References
External links
Fungi described in 1825
Fungi of Asia
Fungi of Europe
Fungi of North America
Inedible fungi
confluens
Taxa named by Christiaan Hendrik Persoon
Fungus species | Phellodon confluens | [
"Biology"
] | 133 | [
"Fungi",
"Fungus species"
] |
47,776,632 | https://en.wikipedia.org/wiki/Aureoboletus%20auriporus | Aureoboletus auriporus is a species of bolete fungus in the family Boletaceae that is found in Europe and North America. It was originally described in 1872 by American mycologist Charles Horton Peck, who called it Boletus auriporus. Zdenek Pouzar transferred it to the genus Aureoboletus in 1957.
The species is edible, and could be confused with (the also edible) Xerocomus illudens.
See also
List of North American boletes
References
External links
auriporus
Edible fungi
Fungi described in 1872
Fungi of Europe
Fungi of North America
Taxa named by Charles Horton Peck
Fungus species | Aureoboletus auriporus | [
"Biology"
] | 135 | [
"Fungi",
"Fungus species"
] |
47,777,088 | https://en.wikipedia.org/wiki/Cardiobacterium%20valvarum | Cardiobacterium valvarum is a Gram-negative species of bacteria belonging to the Cardiobacterium genus. It belongs to the HACEK group of fastidious bacteria that are present in normal oropharyngeal flora and can develop into infective endocarditis.
Microbiology
The only other identified Cardiobacterium species is Cardiobacterium hominis. Cardiobacterium species are Gram-negative, pleomorphic rod-shaped bacteria that are catalase-negative and oxidase-positive. When compared morphologically, the two Cardiobacterium species are indistinguishable in culture and Gram stain, however the two differ in growth patterns: C. valvarum is more fastidious than C. hominis, and is non-hemolytic. C. valvarum is also differentiated by the fact that the species does not produce indole.
Isolates of C. valvarum show optimal growth by day 3 under standard 5% incubation conditions on 5% sheep blood, but scant growth on chocolate agar.
Identification
Members of the HACEK group are difficult to identify through conventional methods. 16S ribosomal RNA genotyping is the necessary method of identifying C.valvarum. C.valvarum bears numerous phenotypic similarities with Pasteurella multocida and is therefore commonly misidentified. The phenylphosphonate reaction and Maldi-TOF mass spectrometry can be used to distinguish the two species.
The Cardiobacterium species are broadly susceptible to beta-lactam, trimethoprim-sulfamethoxazole, fluoroquinolones, and aztreonam. Current clinical guidelines recommend that C. valvarum infection be treated with a 4-week course of ceftriaxone or ciprofloxacin.
References
Gammaproteobacteria | Cardiobacterium valvarum | [
"Biology"
] | 407 | [
"Bacteria stubs",
"Bacteria"
] |
47,777,313 | https://en.wikipedia.org/wiki/C5H4O3 | {{DISPLAYTITLE:C5H4O3}}
The molecular formula C5H4O3 (molar mass: 112.08 g/mol, exact mass: 112.0160 u) may refer to:
2-Furoic acid
Itaconic anhydride
Molecular formulas | C5H4O3 | [
"Physics",
"Chemistry"
] | 65 | [
"Molecules",
"Set index articles on molecular formulas",
"Isomerism",
"Molecular formulas",
"Matter"
] |
47,777,679 | https://en.wikipedia.org/wiki/1%2C2-Dioleoyl-sn-glycerophosphoethanolamine | 1,2-Dioleoyl-sn-glycerophosphoethanolamine is a non-bilayer lipid of the phosphatidylethanolamine class, it adopts non-lamellar reverse hexagonal structures. It forms part of Lipofectamine, a common transfection reagent.
References
Phospholipids
Glycerol esters
Phosphatidylethanolamines | 1,2-Dioleoyl-sn-glycerophosphoethanolamine | [
"Chemistry"
] | 99 | [
"Phospholipids",
"Signal transduction",
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
47,777,700 | https://en.wikipedia.org/wiki/Amphipols | Amphipols (a portmanteau of amphiphilic polymers) are a class of amphiphilic polymers designed to keep membrane proteins soluble in water without the need for detergents, which are traditionally used to this end but tend to be denaturing. Amphipols adsorb onto the hydrophobic transmembrane surface of membrane proteins thanks to their hydrophobic moieties and keep the complexes thus formed water-soluble thanks to the hydrophilic ones. Amphipol-trapped membrane proteins are, as a rule, much more stable than detergent-solubilized ones, which facilitates their study by most biochemical and biophysical approaches. Amphipols can be used to fold denatured membrane proteins to their native form and have proven particularly precious in the field of single-particle electron cryo-microscopy (cryo-EM; see e.g. ).The properties and uses of amphipols and other non-conventional surfactants are the subject of a book by Jean-Luc Popot.
See also
Peptitergents - synthetic peptide sequences which can substitute to detergents to keep membrane proteins water-soluble.
Nanodisc - water-soluble protein-stabilized lipid discs that can trap and stabilize membrane proteins.
References
Surfactants | Amphipols | [
"Chemistry"
] | 266 | [
"Biochemistry stubs",
"Protein stubs"
] |
47,777,731 | https://en.wikipedia.org/wiki/Peptitergents | Peptitergents (a portmanteau of peptide and detergent) are synthetic peptides designed to be lipophilic on one side and hydrophilic on the other upon folding to an α-helical conformation and were designed to solubilize integral membrane proteins in aqueous solution. They can be considered a sub-class of amphipols and are based on earlier fundamental explorations of amphiphilic secondary structures
See also
Amphipols
References
Zwitterionic surfactants | Peptitergents | [
"Chemistry"
] | 108 | [
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
47,777,821 | https://en.wikipedia.org/wiki/Modafinil%20sulfone | Modafinil sulfone (code name CRL-41056) is an achiral, oxidized metabolite of modafinil, a wakefulness-promoting agent. It is one of two major circulating metabolites of modafinil, the other being modafinil acid. Modafinil sulfone is also a metabolite of the modafinil prodrug, adrafinil. Modafinil sulfone is also a metabolite of armodafinil, the (R)-(–)-enantiomer of modafinil, as oxidation to the sulfone removes the chiral center at the sulfur atom. Modafinil sulfone has been described as inactive, and similarly to modafinil acid, does not appear to contribute to the wakefulness-promoting effects of modafinil. However, like modafinil, modafinil sulfone was found to show anticonvulsant properties in animals, indicating that it does possess some biological activity.
See also
List of modafinil analogues and derivatives
References
Acetamides
Anticonvulsants
Benzhydryl compounds
Human drug metabolites
Sulfones
Modafinil analogues | Modafinil sulfone | [
"Chemistry"
] | 268 | [
"Sulfones",
"Functional groups",
"Human drug metabolites",
"Chemicals in medicine"
] |
47,778,259 | https://en.wikipedia.org/wiki/3%2C4-Dimethoxystyrene | 3,4-Dimethoxystyrene (vinylveratrole) is an aromatic organic compound. It is a yellow oily liquid with a pleasant floral odor. Normally, it is supplied with 1-2% of the hydroquinone as an additive to prevent oxidation of the compound.
Occurrence
3,4-Dimethoxystyrene is found in the essential oil of Brazilian propolis. It is also found in cereal products and coffee products.
Uses
3,4-Dimethoxystyrene is typically used in organic synthesis as a monomer in radical polymerization reactions due to the presence of the electron-deficient double bond. This is similar to the parent compound styrene, which can be polymerized into polystyrene.
3,4-dimethoxystyrene can be deprotected using Lewis acid boron tribromide with almost 100% yield. The resulting compound 3,4-dihydroxystyrene is rapidly oxidized in air, which is why 3,4-dimethoxystyrene is preferred as a stable precursor in organic synthesis.
It is an easily polymerizable precursor to polycatechols as it is less susceptible to oxidation in air than other precursors.
Pharmacology
Pharmacokinetics
Once ingested, 3,4-Dimethoxystyrene is found in the cytoplasm, and extracellularly.
Related compounds
3,4-Dihydroxystyrene
Veratrole
References
Monomers
Vinyl compounds
Catechol ethers
Sweet-smelling chemicals
Methoxy compounds | 3,4-Dimethoxystyrene | [
"Chemistry",
"Materials_science"
] | 330 | [
"Monomers",
"Polymer chemistry"
] |
47,778,302 | https://en.wikipedia.org/wiki/Fistulinella%20nivea | Fistulinella nivea is a species of bolete fungus in the family Boletaceae found in New Zealand. First described by mycologist Greta Stevenson in 1962 as a species of Tylopilus, it was transferred to the genus Fistulinella by Rolf Singer. Stevenson originally discovered the bolete in 1955 at Tōtaranui, where it was growing under Nothofagus. Its fruitbody has a white cap with a diameter of up to atop a stipe measuring up long and thick. The pores on the cap underside are up to 1.5 mm in diameter. The pore surface is initially white before changing to pale pink. Spores are ellipsoid, hyaline (translucent), and measure 17–18 by 6–7 μm.
References
External links
Boletaceae
Fungi described in 1962
Fungi of New Zealand
Fungus species | Fistulinella nivea | [
"Biology"
] | 177 | [
"Fungi",
"Fungus species"
] |
47,779,300 | https://en.wikipedia.org/wiki/Hazard%20analysis%20and%20risk-based%20preventive%20controls | Hazard analysis and risk-based preventive controls or HARPC is a successor to the Hazard analysis and critical control points (HACCP) food safety system, mandated in the United States by the FDA Food Safety Modernization Act (FSMA) of 2010.
Preventive control systems emphasize prevention of risks before they occur rather than their detection after they occur. The FDA released the rules in the Federal Register from September 2015 onwards. The first release of rules addressed Preventive Controls for Human Food and Preventive Controls for Foods for Animals. The Produce Safety Final Rule, the Foreign Supplier Verification Programs (FSVP) Final Rule and the Accredited Third-Party Certification Final Rule were issued on November 13, 2015. The Sanitary Transportation of Human and Animal Food final rule was issued on April 6, 2016, and the Mitigation Strategies To Protect Food Against Intentional Adulteration (Food Defense) final rule was issued on May 27, 2016.
Scope
All food companies in the United States that are required to register with the FDA under the Public Health Security and Bioterrorism Preparedness and Response Act of 2002, as well as firms outside the US that export food to the US, must have a written FSMA-compliant Food Safety Plan in place by the deadlines listed below:
Very small businesses of less than $1 million in sales per year are exempt, but must provide proof to the FDA of their very small status by January 1, 2016.
Businesses subject to Juice HACCP () and Seafood HACCP () are exempt.
Businesses subject to the Pasteurized Milk Ordinance; Sept 17, 2018.
Small businesses, defined as having fewer than 500 full-time equivalent employees; Sept 17, 2017.
All other businesses; Sept 17, 2016.
Additionally, for the first time food safety is being extended to pet food and animal feed, with firms being given an extra year to implement Current Good Manufacturing Practices before a Preventive Controls system the following year:
Primary Production Farms, defined as "an operation under one management in one general, but not necessarily contiguous, location devoted to the growing of crops, the harvesting of crops, the raising of animals (including seafood), or any combination of these activities" are exempt.
Very small businesses of less than $2,500,000 in sales per year; Sept 17, 2018 for cGMP, Sept 17, 2019 for Preventive Controls, but must provide proof of very small business status by January 1, 2017.
Small businesses, having fewer than 500 full-time equivalent employees; Sept 17, 2017 for cGMP, Sept 17, 2018 for Preventive Controls.
All other businesses; Sept 17, 2016 for cGMP, Sept 17, 2017 for Preventive Controls.
The FDA estimates that 73,000 businesses currently fall under these definitions.
Differences between FSMA Preventive Controls and HACCP
FSMA places a much stronger emphasis on science, research and prior experience with outbreaks than HACCP. For example, the FDA now uses whole genome sequencing to match the exact strain of pathogen isolated from hospital patients to DNA recovered from food manufacturing facilities.
FSMA requires that a "Preventive Controls Qualified Individual" (PCQI) with training and experience oversee the plan. HACCP assigned responsibilities to a team drawn from management.
FSMA requires that firms vet ("Verify") all their suppliers for the effectiveness of their food safety programs. This has the effect of drafting companies into the FSMA enforcement effort, since the Supplier Verification and Foreign Supplier Verification programs require that the suppliers provide written proof that they have Prerequisite Programs, and Preventive Controls systems which include their own supplier vetting program.
FSMA-compliant Food Safety Plans rely on Prerequisite Programs such as GMPs, allergen controls, Integrated Pest Management and vetting suppliers far more than HACCP plans, since these programs tend to be preventive.
FSMA-compliant Hazard Analyses address radiological hazards in addition to the chemical, biological and physical hazards covered by HACCP systems.
FSMA explicitly requires a Food Defense component, with both terrorism and Economically Motivated Adulteration addressed. Businesses with less than $10,000,000 a year in sales are exempt.
FSMA-compliant Food Safety Plans de-emphasize Critical Control Points in favor of Preventive Controls. Preventive Controls do not require specific Critical Limits.
FSMA-compliant Food Safety Plans allow Corrections in place of Corrective Actions when the public health is not threatened. Corrections are not as strict regarding paperwork as Corrective Actions. The FDA believes that companies might have been avoiding making minor improvements because they felt that the paper trail of a Corrective Action would open them to legal risk due to discovery during investigations or lawsuits.
FSMA-compliant Food Safety Plans are to be reviewed once every three years, as opposed to yearly with HACCP.
See also
Failure mode and effects analysis
Failure mode, effects, and criticality analysis
Fault tree analysis
Food defense
Food safety
Design Review Based on Failure Mode
Fast food restaurant
ISO 22000
Hazard analysis
Hazop
Hygiene
Sanitation
Sanitation Standard Operating Procedures
Codex Alimentarius
Total quality management
References
External links
Food Safety Preventive Controls Alliance's Preventive Controls for Human Food
Food safety
Food technology
Quality management
Hazard analysis
United States Department of Agriculture | Hazard analysis and risk-based preventive controls | [
"Engineering"
] | 1,058 | [
"Safety engineering",
"Hazard analysis"
] |
47,780,890 | https://en.wikipedia.org/wiki/PLC%20technician | PLC technicians design, program, repair, and maintain programmable logic controller (PLC) systems used within manufacturing and service industries ranging from industrial packaging to commercial car washes and traffic lights.
Scope of work
PLC technicians are knowledgeable in overall plant systems and the interactions of processes. They install and service a variety of systems including safety and security, energy delivery (hydraulic, pneumatic and electrical), communication, and process control systems. They also install and service measuring and indicating instruments to monitor process control variables associated with PLCs, and monitor the operation of PLC equipment. PLC technicians work with final control devices such as valves, actuators and positioners to manipulate the process medium. They install and terminate electrical, pneumatic, and fluid connections. They also work on network and signal transmission systems such as fibre optic and wireless.
Along with the calibration, repair, adjustment, and replacement of components, PLC technicians inspect and test the operation of instruments and systems to diagnose faults and verify repairs. They establish and optimize process control strategies, and configure related systems such as Distributed Control Systems (DCSs), Supervisory Control & Data Acquisition (SCADA), and Human Machine Interfaces (HMIs). PLC technicians maintain backups, documentation, and software revisions as part of maintaining these computer-based control systems. Scheduled maintenance and the commissioning of systems are also important aspects of the work. PLC technicians consult technical documentation, drawings, schematics, and manuals. They may assist engineering in plant design, modification and hazard analysis, and work with plant operators to optimize plant controls.
PLC technicians use hand, power, and electronic tools, test equipment, and material handling equipment. They work on a variety of systems including primary control elements, transmitters, analyzers, sensors, detectors, signal conditioners, recorders, controllers, and final control elements (actuators, valve positioners, etc.). These instruments measure and control variables such as pressure, flow, temperature, level, motion, force, and chemical composition. PLC systems designed and maintained by PLC technicians range from high-speed robotic assembly to conveyors, to batch mixers, to DCS and SCADA systems. PLC systems are often found within industrial and manufacturing plants, such as food processing facilities. Alternate job titles include PLC engineer, Automation Technician, Field Technician, or Controls Technician.
Education, training and skills
PLC technician educational courses and programs integrate PLC programming with mechanics, electronics and process controls, They also commonly include coursework in hydraulics, pneumatics, robotics, DCS, SCADA, electrical circuits, electrical machinery and human-machine interfaces. Typical courses include math, communications, circuits, digital devices, and electrical controls. Other courses include robotics, automation, electrical motor controls, programmable logic controllers, and computer-aided design. When performing their duties, PLC technicians must comply with federal, jurisdictional, industrial, and site-specific standards, codes, and regulations. They must ensure that all processes operate and are maintained within these set standards, codes, and regulations. Keeping up-to-date with advances in technology in the industry is important. Key attributes for PLC Technicians are critical thinking skills, manual dexterity, mechanical aptitude, attention to detail, strong problem-solving skills, communication skills, and mathematical and scientific aptitude.
Employers generally prefer applicants who have completed a PLC technician certificate or related associate degree. These programs can be completed at Colleges and Universities in either an in-class or online format. Some Colleges, such as George Brown College, offer an online PLC Technician program that uses simulation software, PLCLogix, to complete PLC lab projects and assignments. Certification by accredited schools and third-party organizations can enhance employment opportunities and keep PLC technicians current and up-to-date. In addition to Colleges and Universities, other organizations and companies also offer credential programs in PLCs, including equipment manufacturers such as Rockwell and professional associations, such as the Electronics Technicians Association, Robotics Industries Association and the Manufacturing Skill Standards Council.
Career opportunities
PLC technicians install and repair industrial electronic equipment (including input/output networks, data highways, variable speed drives, and process control equipment) and write PLC programs for a wide variety of automated control systems, ranging from simple on–off controls to robotics. PLC technicians also find employment in the industrial engineering field where they are actively involved in the design and implementation of PLC control systems.
Career opportunities for PLC Technicians include a wide range of manufacturing and service industries such as automotive, pharmaceutical, power distribution, food processing, mining, and transportation. Other career prospects include areas such as machine assembly, troubleshooting, and testing, systems integration, application support, maintenance, component testing and assembly, automation programming, robot maintenance and programming, technical sales and services.
PLC Technicians work mainly indoors, on the plant floor and sometimes in cramped conditions. They may be required to stand for prolonged periods of time and be exposed to high noise, fumes and heat levels. Because this is such an important job, they must pay close attention to safety and may be called out in emergencies. Constant learning may be required to keep up with new technology.
Primarily work in this area is full-time and can be in shifts. Employers who hire PLC Technicians include:
Automation equipment wholesalers
Industrial manufacturing companies
Water Treatment plants
Nuclear, Wind, Thermal, and Hydro Electric Power companies
Pharmaceutical companies
Mining, petrochemical and natural gas companies
Pulp and paper processing companies
See also
Industrial Control System
References
Programmable logic controllers
Technicians | PLC technician | [
"Technology",
"Engineering"
] | 1,117 | [
"Industrial computing",
"Industrial engineering",
"Automation",
"Programmable logic controllers",
"Industrial automation"
] |
47,780,913 | https://en.wikipedia.org/wiki/Crater%20illusion | In astronomical imaging and Earth imaging, the crater illusion, also known as the dome illusion or crater/dome illusion, is an optical illusion which causes impact craters and other depressions to appear raised as domes or mountains. It is believed to be caused by our being accustomed to seeing light from overhead. When some images are taken from orbit, the light from the sun is nearly horizontal. This is the only time shadows are seen. Our brains are tricked into thinking that the interior of the crater is above the surrounding terrain instead of below it.
Gallery
References
External links
The Dome Illusion!
Lunar Craters inverting Illusion
Crater Optical Illusion
Optical illusions
Impact craters
Space photography and videography | Crater illusion | [
"Physics",
"Astronomy"
] | 135 | [
"Physical phenomena",
"Optical illusions",
"Outer space",
"Optical phenomena",
"Astronomical objects",
"Impact craters",
"Space photography and videography"
] |
47,781,027 | https://en.wikipedia.org/wiki/Nippon%20Screw%20Weight%20System | The Nippon Screw Weight System (NSWS) is an on-site ground survey machine that examines the geotechnical engineering properties of soil. The NSWS was developed to encounter weather abnormalities and natural hazards, saving human lives.
Introduced in 2012 by the National Agriculture and Food Research Organization (NARO), the NSWS was designed to overcome problems with the Method for standard penetration test (SPT).
NSWS was created by 耕三 大北, was the member of 311 earthquake disaster committee
of the Japanese Geotechnical Society. The society released a report in June, 2012 proposing to the Japanese government a use of NSWS to investigate the aftermath of the 2011 Tōhoku earthquake and tsunami.
Features
The NSWS is compact, weighs 120 kg, and has wheels, making it suitable for ground measurement in crowded residential areas. It costs much less than the conventional SPT test and triaxial compression test.
NSWS can measure very soft zones, converted N-value of zero in the ground that had been considered difficult. It has 1.08 cm interval.SPT conducts the test every 50 cm, and 30 cm interval out of 50 cm is tested so the rest, 20 cm, is not measured; that means 40% of an entire hole is unknown. NSWS does not suffer from such a limitation.
NSWS can penetrate the ground diagonally and can cut through soft gravels. NSWS has in-situ shear test capability, the result of the joint research with NARO and Okita-Ko Co., Ltd
NSWS can prepare converted N-value, density, in-situ shear data for Stability Analysis. NSWS enables multi-point surveying due to its diagonal penetration capability and high-mobility. The multiple spots on the weak layers can be analyzed.
See also
Boring (earth)
Cone penetration test
Geotechnical investigation
Soil mechanics
References
External links
National Agriculture and Food Research Organization of Japan Independent Administrative Agency of Japan specialized in research and development of agriculture and food.
Japanese Geotechnical Society
In situ geotechnical investigations
Articles containing video clips
Geotechnical engineering
Land surveying systems | Nippon Screw Weight System | [
"Engineering"
] | 423 | [
"Civil engineering",
"Geotechnical engineering"
] |
47,781,281 | https://en.wikipedia.org/wiki/Andrew%20H.%20Wallace | Andrew Hugh Wallace (1926 – 18 January 2008) was a Scottish-American mathematician.
Biography
Andrew Hugh Wallace was born and raised in Edinburgh, Scotland. He received in 1946 an MA in mathematics from Edinburgh University and in 1949 a PhD from St. Andrews University with thesis Rational integral functions and associated linear transformations. In the 1950s he was an assistant professor of mathematics at the University of Toronto in Canada. In 1959 he became a professor at Indiana University's mathematics department, where he was also department chair. In 1965 he left Indiana to become a mathematics professor at the University of Pennsylvania, where he remained until his retirement as professor emeritus in 1986. For the academic year 1964–1965 and the first five months of 1968 he was a visiting scholar at the Institute for Advanced Study.
In addition to his work in mathematics, Andrew Wallace was an accomplished pianist, dancer, painter, and sailor. His greatest passion during his later life was sailing. He maintained a 35-foot craft. After his retirement, he and a small crew sailed his boat across the Atlantic and Mediterranean to his new home in Crete. He lived in Crete with his second wife Dimitra until he died in 2008.
Upon his death he was survived by his first wife, Angela Wallace (now Angela Kern) and three daughters: Linda Kipp, Susan George, and Corinne Summers. He was also survived by his second wife, Dimitra Chilari and a step-daughter, Irene Chilari. His name is attached to the Lickorish-Wallace theorem.
Selected publication
Articles
Books
References
External links
1926 births
2008 deaths
20th-century American mathematicians
21st-century American mathematicians
Scottish mathematicians
Topologists
Alumni of the University of Edinburgh
Alumni of the University of St Andrews
Academic staff of the University of Toronto
Indiana University faculty
University of Pennsylvania faculty
Mathematicians at the University of Pennsylvania
Institute for Advanced Study visiting scholars
Scientists from Edinburgh
Sir Edmund Whittaker Memorial Prize winners | Andrew H. Wallace | [
"Mathematics"
] | 385 | [
"Topologists",
"Topology"
] |
47,781,975 | https://en.wikipedia.org/wiki/Penicillium%20svalbardense | Penicillium svalbardense is a species of fungus in the genus Penicillium which was isolated from arctic glacial ice.
References
Further reading
svalbardense
Fungi described in 2007
Fungus species | Penicillium svalbardense | [
"Biology"
] | 43 | [
"Fungi",
"Fungus species"
] |
68,923,793 | https://en.wikipedia.org/wiki/Mercedes-Benz%20FO%20engine | The Mercedes-Benz FO engine series (badged as a Sauber engine in 1993) is a family of naturally-aspirated V8 and V10 racing engines, designed, developed and produced by Mercedes, in partnership and collaboration with Ilmor, for Formula One, and used between and . Over years of development, engine power managed to increase, from 690 @ 15,600 rpm, to later 930 hp @ 19,000 rpm. The customer engines were used by Sauber, McLaren, Brawn GP, and Force India.
List of Formula One engines
Applications
Sauber C12
Sauber C13
McLaren MP4/10
McLaren MP4/11
McLaren MP4/12
McLaren MP4/13
McLaren MP4/14
McLaren MP4/15
McLaren MP4-16
McLaren MP4-17
McLaren MP4-18
McLaren MP4-19
McLaren MP4-20
McLaren MP4-21
McLaren MP4-22
McLaren MP4-23
McLaren MP4-24
McLaren MP4-25
McLaren MP4-26
McLaren MP4-27
McLaren MP4-28
Brawn BGP 001
Force India VJM02
Force India VJM03
Force India VJM04
Force India VJM05
Force India VJM06
Mercedes MGP W01
Mercedes MGP W02
Mercedes F1 W03
Mercedes F1 W04
Mercedes-Benz FO engine World Championship results
2 World Constructors' Championships.
4 World Drivers' Championships.
87 race wins.
76 pole positions.
260 podium finishes.
See also
BMW E41 / P80 engine
Cosworth JD / VJ engine
Ferrari V10 engine
Hart 1035 engine
Honda V10 engine
Ilmor 2175 engine
Peugeot F1 engine
Renault RS engine
Yamaha F1 engine
References
FO
Formula One engines
Engines by model
Gasoline engines by model
V10 engines
V8 engines | Mercedes-Benz FO engine | [
"Technology"
] | 371 | [
"Engines",
"Engines by model"
] |
68,925,277 | https://en.wikipedia.org/wiki/BMW%20E41%20/%20P80%20engine | The BMW E41 and P80 series is a family of naturally-aspirated Formula One racing engines, designed and developed by BMW, and introduced in in partnership with Williams, and continued through , during their partnership with Sauber.
Overview
E41
The BMW E41 was a Formula One V10 engine manufactured by BMW.
BMW was the engine supplier to the Brabham Formula 1 team from 1982 to 1987. The team became world champion in 1983 with the turbocharged in-line four-cylinder BMW M12/13. In addition to Brabham, ATS, Arrows, and Benetton also drove with BMW engines at times. After BMW officially withdrew from Formula 1 in 1988, the engines were used under the name of the US company Megatron until turbo engines were banned in 1989.
However, BMW did not completely abandon the design of Formula 1 engines. Various naturally aspirated 3.5-litre twelve-cylinder engines emerged. A new regulation prescribed ten-cylinder engines with a maximum displacement of 3 liters, which led to the creation of the BMW E41/2. This formed the basis for the BMW E41/4 V10 engine with a cylinder bank angle of 72°.
The BMW E41/4 was first used in the Williams FW22 on BMW's return to Formula One on 12 March 2000 at the Australian Grand Prix in Melbourne. Ralf Schumacher finished third in this race – it was the best F1 entry by an engine manufacturer in over 30 years.
Internally, the engines were given detailed designations: the BMW E41/4 with the number R39-9, for example, underwent nine revisions, with R standing for racing specification. In its last expansion stage, which was used at the end of the 2000 season, the BMW E41/4 produced around 810 hp (596 kW) at 17,500 rpm. In qualifying, the engine reached a maximum speed of 17,800 rpm. In the 2001 Formula 1 season, the engine was replaced by the BMW P80.
Specifications
Designation: E41/4R39-9
Displacement: 3.0 liters (2998 cc) V10-72º
Bore × Stroke: 94.0mm × 43.2mm
Valves/cyl.: 4
Cylinder spacing: 107mm
Power @ rpm Max.: 596 kW (810 hp) @ 17,500 rpm
Torque: 350 N.m. (258 lb-ft)
Year: 2000
P80 series
The BMW P80 series is a naturally aspirated Formula One V10 engine produced by BMW.
BMW had been the engine supplier to the Williams F1 team since 2000. The BMW E41/4 engine at that time was a V10 engine with a cylinder bank angle of 72°.
The P80 engine developed by BMW for the 2002 Formula 1 season was used in the Williams FW24 Formula 1 racing car and, like its predecessor, the BMW P80, had a cylinder bank angle of 90°. The displacement was identical with 2998 cc.
The conception of the P82 was started by a team of fewer than 20 employees in January/February 2001. At that time the P80 had not even made its racing debut. The design phase followed from March to June 2001, and testing of the components began in August. On September 21, 2001, the engine, which consists of a total of almost 5,000 individual parts, ran on the test bench for the first time, and on October 3 it was tested in driving operation for the first time.
When asked about the performance data, the BMW Motorsport Director at the time, Mario Theissen, replied: "Told values such as 19,000 rpm and 900 hp are pure speculation."
In the 2003 Formula 1 season, the engine was replaced by the P83; followed by the P84, and its evolution, the P84/5, in 2004 and 2005.
Specifications
Designation: P80
Displacement: 3.0 liters (2998 cc) V10-90º
Bore × Stroke: 95mm × 42.3mm
Valves/cyl.: 4
Cylinder spacing: 103.5mm
Power @ rpm Max.: 656 kW (880 hp) @ 18,000 rpm
Torque: 350 N.m. (258 lb-ft)
Year: 2001
Background
Williams (2000–2005)
After a ten-year absence from Formula One, BMW began evaluating a return to the sport in the late 1990s. In , the marque signed a contract to supply the Williams team with engines. Williams had won the , , and Drivers' Championships, and the Constructors' Championships in all of these years as well as , in a successful partnership with Renault, but the French company withdrew from the sport at the end of , leaving team owner Frank Williams and Technical Director Patrick Head in need of a new engine partnership to remain competitive. As BMW spent 18 months building and testing a normally aspirated, three-litre V10 engine to comply with technical regulations that had changed significantly since the 1980s, the team used old Renault engines rebadged as first Mecachrome and then Supertec.
BMW's E41 engine was ready to compete in the 2000 season, fitted in the FW22 and driven by Ralf Schumacher and Jenson Button. Schumacher scored a podium finish in the engine's first race, and added two more during the course of the season. A series of consistent points-scoring finishes meant that Williams finished a competitive third in the Constructors' Championship, some distance behind the dominant Ferrari and McLaren teams, but ahead of engine manufacturers with more recent experience.
After the relatively conservative E41, BMW designed the more aggressive P80 engine for , a basic type number that was maintained for the remainder of the company's involvement in Formula One. The engine immediately proved to have a significant power improvement, and propelled Schumacher and new teammate Juan Pablo Montoya into contention for race victories. In all, the two drivers scored four race wins, but lost other opportunities through unreliability and racing incidents. The FW23 chassis also lacked the ultimate downforce to compete with the Ferrari and McLaren drivers at every circuit, although it was the class of the field at "power circuits" such as Hockenheim and Monza.
For , the reliability and consistency of the FW24 chassis was much improved, but Ferrari made a more significant step forward with its own F2002 chassis and dominated both championships. The team scored twelve more points than in the previous year and beat McLaren to second place in the Constructors' Championship, but only won a single race with Schumacher at the Malaysian Grand Prix. Moreover, Montoya was unable to win a single race, despite taking seven pole positions.
The Williams team was more competitive in , as both drivers won on two occasions and Montoya remained in contention for the Drivers' Championship until the penultimate race of the season. However, he ultimately fell short, as did the team in the Constructors' Championship, as although the FW25 was often the car to beat in the second half of the season, it took too much time to reach this point.
For , the team produced the FW26 chassis, which featured a radical nose section designed by Antonia Terzi. This design proved ineffective, however, in another year of Ferrari dominance, and Williams slipped to fourth in the Constructors' Championship, with Montoya's victory in the Brazilian Grand Prix its sole win in the 2004 season. Before this result, the team had suffered the embarrassment of a double disqualification from the Canadian Grand Prix due to brake duct irregularities, and then Schumacher sustaining spinal injuries as a result of a high-speed crash at the United States Grand Prix, which caused him to miss six races until he recovered. Both drivers left the team at the end of the season.
The final year of BMW's association with Williams, , saw the team's decline in competitiveness continue, dropping to fifth in the Constructors' Championship. None of the team's three drivers—Mark Webber, Nick Heidfeld and Antônio Pizzonia—were able to win a race; the team's best result was a double podium finish at the Monaco Grand Prix. By this time, the team's relationship with its engine supplier had deteriorated, with BMW believing that its engines were capable of winning championships but were being let down by the Williams chassis they were powering. BMW offered to buy the team outright in the hope of gaining overall control of its Formula One endeavours, but Frank Williams refused; as a result, BMW chose to buy the rival Sauber team instead for , and end its deal with Williams.
BMW Sauber (2006–2009)
BMW bought Swiss team Sauber in June 2005 to form the BMW Sauber F1 Team. The takeover came after BMW's relationship with Williams had deteriorated in the previous months, the partnership ending at the end of the season. The team, operated under a German racing licence, was based at Sauber's headquarters in Hinwil, Switzerland and BMW's headquarters in Munich, Germany.
The team scored two podium finishes and came fifth in 2006, its first season in Formula One. This was followed by a second place in 2007 after the McLaren team had been excluded from the championship. Robert Kubica took the team's only Grand Prix victory at the 2008 Canadian Grand Prix. Following a poor season, BMW withdrew from Formula One and sold the team back to founder Peter Sauber.
2006
For the 2006 season, BMW Sauber signed Nick Heidfeld from Williams to be the lead driver, while World Champion Jacques Villeneuve had his existing two-year contract with Sauber honoured. Robert Kubica was signed as the team's third driver. The team continued to use Sauber's facilities, mostly for chassis construction and wind tunnel testing, while BMW's headquarters in Munich was responsible for building the new 2.4-litre P86 V8 engine, revised technical regulations forcing a change from the 3-litre V10 formula. This replaced the Petronas-badged Ferrari engines which the team had used since 1997. The Sauber team's existing major sponsors, Petronas and Credit Suisse, renewed their contracts with BMW. The team also announced a technical partnership with technology company Intel. The team's new livery, which was maintained throughout its tenure in Formula One, consisted of the traditional BMW blue and white with a hint of red.
Villeneuve scored the team's first points with a seventh-place finish at the Malaysian Grand Prix, after Heidfeld retired from fifth with an engine failure late in the race. Over the first two-thirds of the season the drivers picked up points with a succession of seventh and eighth-place finishes, plus a fourth-place finish for Heidfeld at the Australian Grand Prix. The team ran a radical "twin towers" aero enhancement on the front of the car for the French Grand Prix, which was meant to improve the flow of air over the top of the chassis. The parts were promptly banned by the Fédération Internationale de l'Automobile (FIA) as they were adjudged to impede the drivers' vision and thus compromise safety.
Heidfeld scored the team's first podium finish at the Hungarian Grand Prix from tenth on the grid. This race also saw the début of Robert Kubica, who replaced Villeneuve after the latter had crashed heavily at the preceding German Grand Prix. Kubica finished seventh, although he was later disqualified after his car was found to be underweight. The official reason for Villeneuve's absence was that he was recovering from his previous accident, but the team later announced that the driver change was permanent. Kubica scored BMW Sauber's second podium finish of the season at the Italian Grand Prix, after running in third place for most of the race and leading briefly during the first round of pit stops while Heidfeld finished in eighth. The team scored a total of 36 points to finish fifth in the Constructors' Championship, an improvement on Sauber's eighth position with 20 points in .
2007
On 19 October 2006, BMW announced that Robert Kubica would partner Nick Heidfeld for the 2007 Formula One season with Sebastian Vettel taking the test and reserve driver role. Timo Glock was later signed as the team's second test driver. The team launched its 2007 car, the F1.07, on January 16, 2007.
The new car showed promising form throughout winter testing, topping the time sheets on occasions. However, team principal Mario Theissen declared some reliability concerns before the season's opening race in Australia. Kubica retired from fourth place with a gearbox problem, but Heidfeld took over the position and held it to the end of the race. In the early races of the season, Heidfeld and Kubica scored a series of points finishes and established BMW Sauber as the third-fastest team, behind Ferrari and McLaren. Theissen also made the point that the performance gap between BMW Sauber and the two top teams was less than the gap between BMW Sauber and the teams behind it.
The Canadian Grand Prix brought mixed fortunes for the team. While Heidfeld scored BMW Sauber's best result thus far with a second-place finish, Kubica suffered a huge crash that resulted in a long safety car period. The media was initially told Kubica had broken his leg, but it later proved that he had escaped with only a sprained ankle and concussion. Vettel took his place in the United States Grand Prix, finishing in eighth place and therefore becoming the youngest driver to score a Formula One World Championship point. Later in the season, Vettel moved teams to take a race seat at the Toro Rosso team.
Kubica returned to racing action at the French Grand Prix and proved his recovery by finishing in fourth position. Over the remainder of the season, he and Heidfeld continued their form to score a total of 101 points, which secured the team second in the Constructors' Championship after McLaren's disqualification. Heidfeld scored another podium finish at the Hungarian Grand Prix and scored 61 points to Kubica's 39, while Vettel's sole appearance produced an additional point.
2008
On August 21, 2007, BMW confirmed its driver line-up of Heidfeld and Kubica for the season.
Their 2008 car, the F1.08 was officially launched in Munich at BMW Welt on January 14, 2008. It made its track debut at Valencia the next day, with Robert Kubica driving. Team principal Mario Theissen set the target of the team's first win.
BMW Sauber started the season well with Kubica narrowly missing out on pole after a mistake in his main qualifying lap in Melbourne. He later retired after being hit by Kazuki Nakajima but Heidfeld finished second. Kubica took second in Malaysia, with Heidfeld in 6th setting the fastest lap of the race. The team's points total of 11 was their largest score up to that time. In Bahrain, Kubica scored his and the team's first-ever pole position, beating Felipe Massa by just under three-hundredths of a second. The team went on to finish 3rd and 4th in the race, equalling their highest round points total and promoting them to first place in the constructors' championship for the first time.
The team also attained a second-place finish in the Monaco Grand Prix with Robert Kubica, beating both Ferraris and only trailing the McLaren of Lewis Hamilton by three seconds.
BMW Sauber's first race victory came in the 2008 Canadian Grand Prix, the team achieving a one-two finish with Robert Kubica's first race win and Nick Heidfeld taking second place. The victory came after Lewis Hamilton collided with Kimi Räikkönen in the pitlane, ending the race for both drivers. Kubica was on a different refueling strategy from Heidfeld, who also briefly led the race before securing the one-two finish for BMW Sauber in a comfortable fashion.
After the team's breakthrough win, development was switched to the 2009 season where new regulations come into play. This greatly annoyed Kubica, (who was leading the championship after the Canadian Grand Prix), as he felt they could have had a realistic chance of taking at least one title. The lack of development was reflected with a drop of form throughout the second half of the season, causing BMW to be outpaced by Renault, Toyota, and even Toro Rosso (who started the season as one of the slowest teams) by the end of the season. Despite this, Kubica remained with an outside chance of taking the drivers championship until the Chinese Grand Prix, the 17th round out of 18.
In October the team confirmed that they would stick with Robert Kubica and Nick Heidfeld as their drivers for the Season.
2009
Although BMW Sauber targeted the season as the year they would challenge for the title, their start to the season was a disappointment. Kubica was running in 3rd place in the opening round when he collided with Vettel while battling for 2nd place and was forced to retire. Heidfeld then secured the team's first podium of the year in Malaysia, but after 6 races BMW Sauber had collected a mere 6 points, and occupied 8th place in the Constructors' Championship out of 10 teams. A raft of upgrades was set for Turkey, including an improved regenerative braking system (KERS) and a double-deck diffuser. While the new diffuser was implemented, the KERS could not be made to fit the new car and both drivers raced without the device. After the qualifying session for the British Grand Prix Mario Theissen announced that the team had decided to halt further development KERS; of which BMW had been one of the strongest proponents, and focus instead on improving the car's aerodynamics. This left Ferrari and McLaren as the only remaining users of the KERS system. In the European Grand Prix at Valencia Robert Kubica scored the team's first points since the race in Turkey.
Following a meeting of the BMW board on July 28, the company held at press conference the following morning in which it confirmed the team's withdrawal from Formula One at the end of 2009. Chairman Norbert Reithofer described the decision as a strategic one. The Formula One Teams Association released a statement in response pledging its support to help the team remain in F1.
On 15 September 2009, it was announced that BMW Sauber had secured a buyer, Qadbak Investments Limited which said to represent European and Middle Eastern interests. However Lotus had been given the 13th and final slot in the 2010 Championship. The team were awarded what was termed a 14th entry, which hinged either on another team dropping out or all the other teams agreeing to allow 28 cars to enter the 2010 Championship.
On November 22, Swiss newspaper SonntagsZeitung revealed that Qadbak's attempt to purchase the team had failed as it did not have the necessary funds. Qadbak turned out to be a shell company with no assets and no investors behind it. On November 27, 2009, it was announced that Peter Sauber would repurchase the team conditional upon the team receiving a FIA entry for the 2010 season. The FIA subsequently granted Sauber an entry on December 3. The team used Ferrari engines in .
Complete Formula One results
(key)
Formula One World Championship results
11 race wins.
17 pole positions.
62 podium finishes
See also
Asiatech F1 engine
Cosworth CR engine
Ferrari V10 engine
Honda V10 engine
Mercedes-Benz FO engine
Peugeot F1 engine
Renault RS engine
Toyota RVX engine
References
BMW engines
Formula One engines
V10 engines
V8 engines
Gasoline engines by model
Engines by model | BMW E41 / P80 engine | [
"Technology"
] | 4,036 | [
"Engines",
"Engines by model"
] |
68,926,710 | https://en.wikipedia.org/wiki/Thraustochytrium%20pachydermum | Thraustochytrium pachydermum is a species of heterokont.
References
Heterokont species
Marine microorganisms
Protists described in 1958 | Thraustochytrium pachydermum | [
"Biology"
] | 38 | [
"Marine microorganisms",
"Eukaryotes",
"Microorganisms",
"Eukaryote stubs"
] |
68,927,917 | https://en.wikipedia.org/wiki/Miriam%20Higgins%20Thomas | Miriam Mason Higgins Thomas (June 22, 1920 – September 15, 2002) was an American chemist, based in the United States Army Research and Development Command at Natick, Massachusetts.
Early life and education
Miriam Mason Higgins was born in Chicago, the daughter of William Henry Higgins and Mame Mason Higgins. Her mother was an alumna of the University of Chicago, dean of women at Bethune-Cookman College, and a social service consultant for the Illinois Department of Public Aid. Her brother, William H. Higgins, was a dentist and ordained Methodist minister. Her grandfather, M. C. B. Masons, was a noted orator and Black church leader.
Higgins graduated from Hyde Park High School in 1936, and earned a bachelor's degree in nutrition and chemistry from Bennett College in 1940. She earned a master's degree in food chemistry from the University of Chicago.
Career
Thomas taught at the University of Chicago during World War II, and was a chemist with Food and Container Institute at the Chicago Quartermaster Depot beginning in 1945. She was a research chemist at the U. S. Army Natick Develoopment Center, studying nutritional content of military rations under various conditions. In 1975 she won an Army SARS Fellowship to study food processing and nutrition analysis techniques in Japan, India, the Soviet Union, the Netherlands, and Guatemala. She was a consultant to the Food Research Laboratories, Inc., of Boston, and taught nutrition and food science courses at the Massachusetts Institute of Technology. Her research was published in academic journals including Journal of Microwave Power and Journal of Food Science.
Thomas was nominated three times by the Department of the Army for the Federal Woman's Award. She was a member of the Association of Vitamin Chemists, the Society for Nutrition Education, and the American Association for the Advancement of Science.
Selected publications and reports
"Use of Ionizing Radiation to Preserve Food" (1988)
"Effective of Processing and Preparation for Serving on Vitamin Content in T, B, and a Ration Pork" (1986, with Bonita Atwood and K. Ananth Narayan)
"Stability of Vitamins C, B1, B2 and B6 in Fortified Beef Stew" (1986, with Bonita M. Atwood and K. Ananth Narayan)
"Thiamin and Riboflavin Content of Flake-cot Formed Pork Roasts" (1982, with R. V. Decareau and Bonita M. Atwood)
"Effect of Radiation and Conventional Processing on the Thiamin Content of Pork" (1981, with Bonita M. Atwood, E. Wierbicki, and I. A. Taub)
"Nutritional Aspects of Food Irradiation: An Overview" (1979, with E. S. Josephson and W. K. Calhoun)
"Radappertization of Meat, Meat Products, and Poultry" (1972, with E. S. Josephson, A. Brynjolfsson, E. Wierbicki, D. B. Rowley, C. Merritt, R. W. Baker, and J. J. Killoran)
"Effect of Irradiation Dose and Temperature on the Thiamine Content of Ham" (1971, with E. Wierbicki)
"High-Dose Radiation Processing of Meat, Poultry, and Seafood Products" (1970, with E. Wierbicki, A. Anellis, J. J. Killoran, E. J. Johnson, and Edward S. Josephson)
"Radiation Preservation of Foods and Its Effect on Nutrients" 1970, with Edward S. Josephson)
"Effect of Freeze-Thaw Cycling on the Vitamin Content of the Meal Ready-to-Eat, Individual" (1969, with Doris E. Sherman)
"Modified Microbiological Procedures for Vitamin Assays: A Manual" (1962)
"The Nutrient Composition of the Meal, Combat, Individual" (1962)
"Vitamin Retention in Fortified Fruit Tablets During Surgery" (1961)
"Nutritional evaluation of dehydrated foods and comparison with foods processed by thermal and radiation methods" (1961, with Doris Howes Calloway)
"Effect of Storage on the Flavor of Chocolate Fortified with Nutritional Yeast" (1957, with A. L. Sheffner and Harry Spector)
"Effect of Electronic Cooking on Nutritive Value of Foods" (1949, with S. Brenner, A. Eaton, V. Craig)
Personal life
Miriam Higgins married before 1960 and had a son, Brian. Thomas died in 2002, aged 82 years. Her papers are in the National Archives for Black Women's History.
References
1920 births
2002 deaths
Scientists from Chicago
Bennett College alumni
University of Chicago alumni
American women chemists
20th-century African-American scientists
Food chemists
20th-century African-American women | Miriam Higgins Thomas | [
"Chemistry"
] | 978 | [
"Food chemists",
"Food chemistry"
] |
68,928,715 | https://en.wikipedia.org/wiki/Bridget%20Mutuma | Bridget K. Mutuma is a researcher in chemistry and material sciences at Nairobi University in Kenya. She focuses on developing nanomaterials associated with sensors. She is a Fellow of the African Academy of Sciences.
References
External links
Year of birth missing (living people)
Living people
Fellows of the African Academy of Sciences
Academic staff of Kirinyaga University
Nanotechnologists
University of the Witwatersrand alumni
21st-century Kenyan women scientists
21st-century Kenyan scientists | Bridget Mutuma | [
"Materials_science"
] | 96 | [
"Nanotechnology",
"Nanotechnologists"
] |
68,929,069 | https://en.wikipedia.org/wiki/Traditional%20Chinese%20roofing | Traditional Chinese roofing refers to the numerous types of roofing, and roofing elements, employed in historic Chinese architecture. Traditional Chinese architecture employed a number of different roofing styles, which utilized different shapes, slopes, and ridges. The types of roofs would vary by historical era, with certain types of roofs gaining particular prominent through the reigns of certain dynasties. Other factors which shaped roofs in traditional Chinese architecture included precipitation and cultural connotations.
Varieties
Traditional Chinese architecture employed numerous different roofing styles, most of which were sloped, although some flat roofs () were employed. Flat roofs were particularly common in regions of Chinese with less precipitation, such as northern China. Among sloped roofs (), traditional Chinese architecture employs single slope roofs (), two slope roofs (), and four slope roofs (). Depending on the type of gable employed, there are two styles of two slope roofs: gable roofs (, also known as baoguiqi) and (, also known as overhanging gable roofs). Among four slope roofs, there are two styles: the five-ridged hip roof (, also called the Chinese Hipped Roof or the fudian roof) and the nine-ridged xieshan roof ().
Traditional Chinese architecture also includes many types of tented roofs (), including three-corner tents (), four-corner tents (), six-corner tents (), eight-corner tents (), and rounded tents ().
Ridgeless roofs, such as cuanjian roofs, have also been employed in traditional Chinese roofing, most notably, perhaps, in the Hall of Prayer for Good Harvests at the Temple of Heaven.
Other roof types include (), (, also called open plat roofs), and (). Lu roofs have a flat top, with four diagonal ridges surrounding the top. These roofs were particularly common throughout the Yuan dynasty.
Some traditional Chinese buildings have swastika-shaped roofs (), due to the shape's historic connotations of luck and auspiciousness.
Roofs joined by multiple pieces, known as joined roofs () were often constructed in traditional Chinese architecture to enable a large floor area without much height.
Roofs with juanpeng ridges (), known as () or parabolic roofs, have been common in Chinese architecture since ancient times. Many buildings at the Chengde Mountain Resort, a Qing dynasty complex of imperial palaces, employ juanpeng roofs.
Checkerboard roofs (), named due to their checkered patterns, have also been employed in residential architecture.
Elements
Traditional Chinese roofs are also distinguished by a number of distinct roofing elements, such as ridges. In addition to the main ridges (), certain traditional Chinese roofs have additional ornamental ridges, such as () and juanpeng ridges ().
Certain types of (, also known as overhanging gable roofs) employ juanpeng ridges at each end of the gable, in lieu of a main ridge.
In the county-level city of Jinjiang, in Fujian province, many older houses have downspouts (known locally as chuizhu) coming down from the edges of their roofs.
See also
Chinese architecture
List of roof shapes
References
Architecture in China
Roofs | Traditional Chinese roofing | [
"Technology",
"Engineering"
] | 656 | [
"Structural system",
"Structural engineering",
"Roofs"
] |
68,931,030 | https://en.wikipedia.org/wiki/Allogeneic%20processed%20thymus%20tissue | Allogeneic processed thymus tissue, sold under the brand name Rethymic, is a thymus tissue medical therapy used for the treatment of children with congenital athymia. It takes six months or longer to reconstitute the immune function in treated people.
The most common adverse reactions include high blood pressure, cytokine release syndrome, low blood magnesium levels, rash, low platelets, and graft versus host disease.
It was approved for medical use in the United States in October 2021. Allogeneic processed thymus tissue is the first thymus tissue product approved by the U.S. Food and Drug Administration (FDA).
Allogeneic processed thymus tissue is composed of human allogeneic (donor-derived) thymus tissue that is processed and cultured, and then implanted into people to help reconstitute immunity (improve immune function) in people who are athymic. Dosing is patient customized, determined by the surface area of the allogeneic processed thymus tissue slices and the body surface area of the patient.
Medical uses
Allogeneic processed thymus tissue is indicated for immune reconstitution in children with congenital athymia.
History
The safety and efficacy of allogeneic processed thymus tissue were established in clinical studies that included 105 participants, with ages from one month to 16 years, who each received a single administration of allogeneic processed thymus tissue, from 1993 to 2020. Allogeneic processed thymus tissue improved survival of people with congenital athymia, and most people treated with this product survived at least two years.
The U.S. Food and Drug Administration (FDA) granted the application for allogeneic processed thymus tissue a rare pediatric disease voucher and granted approval of Rethymic to Enzyvant Therapeutics, Inc.
References
Further reading
Congenital disorders
Immunology
Medical treatments
Orphan drugs
Thymus | Allogeneic processed thymus tissue | [
"Biology"
] | 395 | [
"Immunology"
] |
68,931,434 | https://en.wikipedia.org/wiki/Lamborghini%20LE3512 | The Lamborghini LE3512 was a naturally-aspirated V12 motor racing engine, designed and developed by Lamborghini, to compete in Formula One. The engine was raced between and .
Formula One
Lamborghini made the move to Formula One in when the FIA outlawed turbocharged engines. Former Scuderia Ferrari designer / engineer Mauro Forghieri was commissioned to design and build a new, 3.5 litre V12 engine for use by the French Larrousse team in 1989. Dubbed the Lamborghini LE3512, (Lamborghini Engineering 3.5 liters 12 cylinders) the , 80° V12 engine was reported to be the best sounding engine of the new 3.5L naturally aspirated formula. Lamborghini representatives stated at the engine's début race, the 1989 Brazilian Grand Prix in Rio de Janeiro, that they chose a lower ranked team to join Formula One (Larrousse was in its third season using Lola chassis) as it was felt at the early stage of its development the 3512 would not be able to do justice to one of the teams usually closer to the front of the grid. Also, the front running teams already had existing engine suppliers in place (McLaren with Honda, Williams with Renault, Benetton with Ford, and Ferrari who made their own V12 engines).
The Lamborghini V12 did impress many in 1989 despite its unreliability, and the engine's best result in its first year came thanks to fast but accident-prone Larrousse driver Philippe Alliot when he qualified his Lola LC89 in 5th position for the Spanish Grand Prix at Jerez, only 1.417 seconds slower than the V10 McLaren-Honda of pole winner Ayrton Senna. Alliot then backed up that performance by scoring the engine's first point in Formula One by finishing 6th in the race and setting the 4th fastest race lap in the process. Unfortunately, Alliot's teammate for the second half of 1989, former Ferrari driver Michele Alboreto, never came to grips with either the Lola or the Lamborghini. In his eight races for Larrousse he recorded four DNF's, two failures to pre-qualify, one failure to qualify, and a single 11th-place finish in Portugal.
The Lamborghini V12's best finish came when Larrousse driver Aguri Suzuki finished 3rd in the infamous 1990 Japanese Grand Prix at Suzuka. Its time in Formula One (1989-1993) would prove to be frustrating though as poor reliability became the norm for the engine, despite being used by Grand Prix winning teams such as Lotus and Ligier who could boast driving talent such as Derek Warwick (Lotus - 1990), and Thierry Boutsen (Ligier - 1991). In a 2014 interview, Warwick said of the 3512 that it was "All noise and no go".
In 1993 after four years in Formula One with only one significant result for the engine, Bob Lutz of Lamborghini's parent company Chrysler, did a hand-shake deal with McLaren boss Ron Dennis for the team to test the LE3512 to evaluate its potential as a race winner. McLaren made a modified version of their race car, the McLaren MP4/8 dubbed the MP4/8B, to test the engine (the test car took three months to modify to fit the longer and heavier V12). Testing was completed by triple World Champion Ayrton Senna, and future dual World Champion Mika Häkkinen at both the Silverstone Circuit in England and the Estoril circuit in Portugal. After his first drive of the car at Silverstone, Senna suggested certain changes to Forghieri (a less brutal 'top end' and a fatter mid-range), and he complied with engine power increased from to approximately and both drivers were very impressed despite the engine still being somewhat unreliable (Häkkinen reported a massive engine blow up while testing at Silverstone, though he did manage to lap the 5.226 km (3.260 mi) circuit some 1.4 seconds faster than the teams MP4/8 race car powered by a Ford V8 engine). According to reports, Senna even wanted to race the engine at the Japanese Grand Prix believing that while reliability might be a problem, at least he would be quicker than with the Ford powered race car (ironically Senna would win in both Japan and the last race in Australia with the existing MP4/8). Despite this however, Ron Dennis decided to go with Peugeot V10 engines in due to a better commercial agreement that would give long term stability to the team and at the end of the 1993 season, the Lamborghini LE3512 was retired from Grand Prix racing after the company was sold by Chrysler to an Indonesian investor group led by Tommy Suharto.
The Lamborghini, which on all cars it powered carried the words "Chrysler powered by Lamborghini" (other than the McLaren MP4/8B which was all virgin white, though the test engines were badged as Chrysler), was one of only five V12 engines used in the naturally aspirated era from 1989–2013, the others being from Ferrari (1989-1995), Honda (1991-1992), Yamaha (1991-1992), and Porsche (1991). The only other 12 cylinder engines in Formula One during this time were disastrous efforts by Life Racing Engines with their W12 engine and Subaru who reintroduced the Flat 12 to the sport, both appearing in the first half of 1990.
Sportscar racing
The Lamborghini LE3512 also saw limited use in the World Sportscar Championship in 1991. Lamborghini briefly teamed with Konrad Motorsport ran by Austrian driver and team founder Franz Konrad to run the V12 engine in a new chassis called the Konrad KM-011. Unfortunately, the car, driven by Stefan Johansson and Franz Konrad, failed to qualify for its first race at the Nürburgring, though it would qualify for the next round at Magny-Cours, but only lasted 18 laps before retiring with a failed starter motor.
The car was entered by Konrad for the 1992 World Sportscar Championship, but Konrad instead chose to race his more reliable Porsche 962.
LE3512 power output
- @ 11,200 rpm
- @ 13,000 rpm
- @ 13,000 rpm
- @ 13,800 rpm
- @ 13,800 rpm
1993 - @ 13,800 rpm (McLaren tests)
F1 statistics 1989-1993
Races - 80 (49 starts)
First Race - 1989 Brazilian Grand Prix at Jacarepaguá
First Chassis - Larrousse Lola LC88C
Last Race - 1993 Australian Grand Prix at Adelaide
Last Chassis - Larrousse LH93
Wins - 0
Pole Positions - 0
Podiums - 1 (3rd - 1990 Japanese Grand Prix at Suzuka, Aguri Suzuki, Larrousse Lola LC90)
Points - 20
Teams - Larrousse (, , , ), Lotus (1990), Ligier (), Modena Team (1991), Minardi ()
Best Qualifying - 5th, Philippe Alliot, Larrouse Lola LC89, 1989 Spanish Grand Prix at Jerez
Best Constructors' Championship - 6th, Larrousse, 1990 (11 points)
Best Drivers' Championship - 12th, Aguri Suzuki, 1990 (6 points)
See also
Ferrari V12 F1 engine
Honda V12 engine
Yamaha F1 engine
References
External links
Lamborghini.com official website
V12
Engines by model
Gasoline engines by model
V12 engines
Formula One engines | Lamborghini LE3512 | [
"Technology"
] | 1,552 | [
"Engines",
"Engines by model"
] |
68,934,212 | https://en.wikipedia.org/wiki/Isao%20Ijima | was a Japanese zoologist known for his studies of sponges (Porifera) — including his circumscription of the genus Staurocalyptus — leeches (Hirudinea), flatworms (Turbellaria), birds, and fish. Professor of Zoology at Tokyo Imperial University, he is considered the founder of parasitology in Japan and was the first President of the Ornithological Society of Japan. Taxa named in his honour include Ijima's sea snake and Ijima's leaf warbler.
Biography
Born in Hamamatsu in 1861 into a samurai family of Hamamatsu Domain, at the age of fifteen he entered the Kaisei Gakkō [ja] school in Tokyo, before enrolling as a student in the Science College at the Imperial University, Tokyo in 1878. There he studied under Edward Sylvester Morse and Charles Otis Whitman. In 1879, together with , both having previously received training from and assisted Morse in his exploration of the Ōmori Shell Mounds, Ijima excavated the Okadaira Shell Mound; this is credited with being the first modern archaeological survey conducted solely by Japanese. Upon graduation in 1881, as one of three from the first cohort in the Department of Zoology, he became an assistant in the College. The next year he went to Germany to study zoology at the University of Leipzig, where he spent three years working under the direction of Doctor Rudolf Leuckart; he was awarded his Ph.D. in 1884.
Returning to Japan in 1886, at the age of 25 he was appointed Professor of Zoology at the Imperial University, Tokyo, where he remained until his death. In 1893, with the description of Parus owstoni (now Sittiparus owstoni or Owston's tit), he became the first zoologist from Japan to describe a bird. In 1903, he was involved in the establishment of and in 1904 he was appointed the second director of the Misaki Marine Biological Station [ja]. In 1912, he was the founding president of the Ornithological Society of Japan. In 1918, he published his influential . In his personal life, Ijima enjoyed hunting, shooting, fishing, wine, and smoking a pipe. He died in 1921.
See also
Eponyms of Isao Ijima
References
1861 births
1921 deaths
Spongiologists
Taxon authorities
Japanese zoologists
Japanese archaeologists
People from Hamamatsu | Isao Ijima | [
"Biology"
] | 492 | [
"Taxon authorities",
"Taxonomy (biology)"
] |
68,937,399 | https://en.wikipedia.org/wiki/Ferrari%20V8%20F1%20engine | Ferrari has manufactured three naturally-aspirated V8 racing engines, designed for Formula One racing. First, the Tipo DS50 engine introduced in ; with the 2.5 L engine configuration. Second, the Tipo 205/B engine, introduced in ; with the 1.5 L engine configuration; and was designed by Franco Rocchi and Angelo Bellei. Then, a 42-year hiatus; until the FIA imposed a 2.4 L engine V8 configuration for all Formula One teams in , with Ferrari introducing their Tipo 056; designed by Gilles Simon.
Tipo DS50
The Tipo DS50 engine, used in the Ferrari D50, was introduced in 1954. This engine was a , 90°, naturally aspirated, front-mounted V8; which produced between and .
Tipo 205/B
The Tipo 205/B engine developed @ 11,000 rpm; and had a bore and stroke of .
Tipo 056
Ferrari Type 056 was introduced by Ferrari, who used it in Formula 1 between 2006 and 2013. The V8 engine was developed under engine chief Paolo Martinelli and thus marked the return of Ferrari's usage of a V8 engine after a forty-year absence. Its predecessor is the Tipo 055 used in the 2005 season, successor type 059/3 from 2014.
Development
After the FIA had decided to introduce V8 engines from the 2006 season, Ferrari began developing such an engine for use in a Formula 1 car in mid-2004. In August 2005 the first test drives took place. For this purpose, the Tipo 056 was installed in a modified F2004. The road car engine department helped develop the Tipo 056. The engine management was by Magneti Marelli.
Usage
Ferrari used the engine from 2006 to 2013. In the 2009 and 2011 to 2013 seasons, Ferrari used the Tipo 056 in conjunction with KERS.
Red Bull also used the engine in 2006, but sourced its engines from Renault from the next season.
Scuderia Toro Rosso drove the Type 056 from 2007 to 2013, with KERS in the 2011 and 2013 seasons.
Spyker built the Type 056 in 2007, its successor Force India in 2008. For the 2009 season, Force India switched to Mercedes as the engine supplier.
From the 2010 to 2013 season, Sauber also obtained its engines from Ferrari. Sauber used KERS from the 2011 season.
On the very first race weekend in Bahrain in 2006, Michael Schumacher secured pole position in the Ferrari 248 F1 with the Tipo 056. The first victory followed three races later at the San Marino Grand Prix, also by Schumacher. Fernando Alonso 's last victory with the Tipo 056 came at the 2013 Spanish Grand Prix. The most victories per season were nine, which was achieved three times with the Type 056 – in 2006, 2007, and 2008.
The Tipo 056 claimed 39 victories in 147 races (including 38 by Ferrari and one by Toro Rosso). Its drivers took 29 pole positions and set the fastest laps in 48 races. A driver with Tipo 056 stood on the podium 122 times. With him, Ferrari won a drivers' and two constructors' world championships.
Specifications
Weight: 95 kg
Configuration: 90° V8
Valves: 4 per cylinder
Bore: 98mm
Stroke: 39.75mm
Displacement: 2.4 liters
No. of revolutions: Max. 19,000 rpm
Exhaust: Two outlet pipes
Power output: ~ 597 kW (800 hp)
Torque output: ~ 325 N.m. (240 lb-ft)
Types
Tipo DS50 (1955-1957): - @ 8,100 rpm
Tipo 205/B (1964-1965): - @ 11,000 rpm
Tipo 056 (2006-2013): - @ 18,000-19,000 rpm
Applications
Ferrari D50
Ferrari 158
Ferrari 248 F1
Ferrari F2007
Ferrari F2008
Ferrari F60
Ferrari F10
Ferrari 150º Italia
Ferrari F2012
Ferrari F138
Red Bull RB2
Toro Rosso STR2
Toro Rosso STR3
Toro Rosso STR4
Toro Rosso STR5
Toro Rosso STR6
Toro Rosso STR6
Toro Rosso STR7
Toro Rosso STR8
Spyker F8-VII / Force India VJM01
Sauber C29
Sauber C30
Sauber C31
Sauber C32
Formula One World Championship results
3 World Constructors' Championships
3 World Drivers' Championships
47 race wins
51 fastest laps
143 podium finishes
References
Engines by model
Ferrari engines
Formula One engines
Gasoline engines by model
V8 engines
Lancia engines | Ferrari V8 F1 engine | [
"Technology"
] | 935 | [
"Engines",
"Engines by model"
] |
68,938,707 | https://en.wikipedia.org/wiki/Hypidone | Hypidone (developmental code name YL-0919) is an investigational serotonergic antidepressant which is under development for the treatment of major depressive disorder. It acts as a serotonin reuptake inhibitor, 5-HT1A receptor partial agonist, and 5-HT6 receptor full agonist. It is used as the hydrochloride salt. As of January 2021, hypidone is in phase 2 clinical trials for major depressive disorder.
See also
List of investigational antidepressants
References
External links
Hypidone hydrochloride - AdisInsight
5-HT1A agonists
5-HT6 agonists
Tertiary alcohols
Antidepressants
Benzyl compounds
Ketones
Piperidines
2-Pyridones
Serotonin reuptake inhibitors
Experimental antidepressants | Hypidone | [
"Chemistry"
] | 182 | [
"Ketones",
"Functional groups"
] |
68,941,004 | https://en.wikipedia.org/wiki/National%20Oil%20Spill%20Detection%20and%20Response%20Agency | The National Oil Spill Detection and Response Agency (NOSDRA) is an agency under the Federal Ministry of Environment in Nigeria. It was instituted by the National Assembly of the Federal Republic of Nigeria act of 2006 with the core mandate to oversee the implementation of the National Oil Spill Contingency Plan (NOSCP) which also incorporates the National Oil Spill Contingency System (NOSCS) for Nigeria.
This is to ensure compliance to Nigeria's signatory to the International Convention on Oil Pollution Preparedness, Response and Cooperation (OPRC, 1990). Therefore, the agency has focused on building conformance with environment legislation in the Nigerian petroleum sector from inception. NOSDRA is the lead agency for other oil spill contingency plans in Nigeria, including the ports and industries. It fulfils its mandate through joint investigation visits, environmental remediation of impacted sites, monitoring oil spill drill exercises and facilitating inspections.
These activities are carried out across the country through their zonal offices located mostly in the Niger-Delta region including Port Harcourt, Warri, and Uyo where oil exploration and production are prevalent. They also have zonal offices in Lagos, Kaduna, Kogi, Gombe and Akure, with their headquarters in Abuja, Nigeria. However, the agency implements tier 3 oil spill response monitoring from its national control and response centre. They employ the oil spill monitor and gas flare tracker in reporting oil and gas pollution related matters. The frequency of oil spill incidents recorded by the agency prompted them to commence the development of a National Oil Spill Compensation Rate (NOSCR) in 2017 to guide the oil industry in establishing an acceptable and appropriate compensation to host and transit oil communities.
The agency prioritizes high-risk areas for protection and effective clean-up with the aid of a baseline environmental sensitivity index map (ESI) and covers the midstream and downstream in its environmental compliance monitoring role. Despite the scope of the NOSDRA, it is perceived not to be exhaustive and resulted in a demand for amendment in 2017. The amendment proposed to replace it with the National Oil Pollution Management Agency (NOPMA) and to expand its provisions to tackle not only oil spillage, but also oily waste, gas flare and obnoxious substances in the country's petroleum sector. It also calls for provisions to regulate all tiers of oil spills, increased fines and penalties for polluters and improved funding. The amendment bill passed by the Nigerian National Assembly in 2019 was refused by the president, Muhammadu Buhari as a result of the observations in the proposed legislation.
References
2006 establishments in Nigeria
Government agencies established in 2006
Government agencies of Nigeria
Oil spills
Environmental agencies | National Oil Spill Detection and Response Agency | [
"Chemistry",
"Environmental_science"
] | 541 | [
"Oil spills",
"Water pollution"
] |
68,944,910 | https://en.wikipedia.org/wiki/Vaccination%20in%20Bangladesh | Vaccination in Bangladesh includes all aspects of vaccination in Bangladesh.
A 2020 study reported that the cost of a malaria vaccination program in Bangladesh would be cost effective in terms of increasing the people's disability-adjusted life years.
Bangladesh had its first outbreak of avian influenza in 2007 and the disease continues to be a national problem. Part of the response that scientists recommend is the development of vaccination programs, but this has been difficult.
A 2016 program to provide HPV vaccines to girls created a range of ethical issues for communities. The source of all the problems was that the design of the vaccination program came from foreign people outside the country who had no understanding of local cultural norms. There was an attempt at local consultation, but unexpected problems happened anyway. Problems included lack of public health education for the communities receiving the vaccine, forcefulness and lack of consent in arranging for girls to take the vaccine, a lack of planning to treat adverse side effects of vaccination, and a lack of female leadership and empowerment in running a health program for females.
There are multiple cholera vaccines available in Bangladesh as well as multiple strategies for making them available to people who need them. While there is major government support for vaccination, there is debate and research about how to manage the vaccination program to make it more efficient.
Bangladesh has experienced outbreaks of the Nipah virus and although a vaccine exists, the vaccine option is not well developed and preventing outbreaks without vaccines is a better option in this case.
Bangladesh began a vaccination program for congenital rubella syndrome in 2012 and since then, cases have gone down greatly.
COVID-19 vaccination
Bangladesh began the administration of COVID-19 vaccines on 27 January 2021 while mass vaccination started on 7 February 2021.
EPI (Expanded program on immunization) in Bangladesh
On 7th April 1979, about 5 years after EPI was launched globally by WHO, EPI was formally launched in Bangladesh as a pilot project in eight thanas. In 1985, the People’s Republic of Bangladesh committed to the Global Universal Child Immunization Initiative (UCI), and began a phase-wise process of EPI intensification from 1985-1990.
Bangladesh has made significant progress in the elimination and control of Vaccine-preventable disease (VPDs). The last case of wild Poliovirus was detected in 2006 and maintains Polio free since then. Maternal and neonatal tetanus was eliminated in 2008. Bangladesh also achieved rubella control goal in 2018. Surveillance for AFP and measles is maintained at standard level. Bangladesh has also introduced several new vaccines since last decades. HepB vaccine was introduced in 2003, Hib in 2009, rubella in 2012, PCV and IPV in 2015, MR second dose in 2015 and fIPV in 2017.
References
Bangladesh
Healthcare in Bangladesh | Vaccination in Bangladesh | [
"Biology"
] | 585 | [
"Vaccination by country",
"Vaccination"
] |
68,945,459 | https://en.wikipedia.org/wiki/Corsi%E2%80%93Rosenthal%20Box | The Corsi–Rosenthal Box is a design for a do-it-yourself air purifier that can be built comparatively inexpensively. It consists of four
or five HVAC particulate air filters that form a cube and a box fan to draw air through the filters. The seams of the cube are sealed with duct tape. A 2022 study found the clean air delivery rate on the five-filter design was between per minute (depending on fan speed), costing roughly a tenth of commercial air filters. Engineers Richard Corsi and Jim Rosenthal created the five-filter design during the COVID-19 pandemic, with the goal of reducing the risk of infection by reducing the levels of airborne viral particles in indoor settings.
Background and history
The basic idea of an air filter taped to a box fan has been well known for many years for use in workshops and for improving home air quality. University of Michigan Medicine published an instructional video on this in 2011 and there are many online discussions and DIY blog posts predating 2020
COVID-19 is primarily transmitted through the air and superspreading events are generally associated with indoor gatherings where the virus is allowed to accumulate in the air. In response, and on recommendations of infectious disease researchers, engineers began to consider how improved ventilation may reduce risk of infection by reducing the amount of virus in indoor air.
Air purification units (room or multi-room) with HEPA filtration range widely in price from under $50 to considerably more than . In August 2020, Richard Corsi, an environmental engineer and the incoming Dean of Engineering at the University of California, Davis, spoke with Wired reporter Adam Rogers about an idea he had for combining multiple store-bought filters with a box fan to improve the efficiency of home-made air filter designs. Rogers contacted Jim Rosenthal, the CEO of filter manufacturer Tex-Air Filters, who had collaborated with Corsi at the University of Texas and in the Texas chapter of the Asthma and Allergy Foundation of America, to run some tests on a single air filter attached to a box fan. Inspired by Corsi's idea to use multiple filters, Rosenthal later came up with a five-filter design. Rosenthal named it after Corsi, although after a New York Times article mentioned the boxes by that name, Corsi tweeted that Rosenthal really deserved the credit, and that he preferred the name Corsi–Rosenthal Box. HVAC experts Neil Comparetto and John Semmelhack modified the design in October 2020 to use 4 filters and a cardboard bottom, in a design called the Comparetto Cube.
Design
The Corsi–Rosenthal Box design consists of four or five HVAC filters of effectiveness MERV13 or higher, which form the side walls of a box. Four-filter design variants use 20-inch wide filters, secured with duct tape and a piece of cardboard forming the bottom of the box. In Rosenthal's design from 2020, two 16×20×2-inch filters and three 20×20×2-inch filters form five sides of the cube. For both, a box fan makes the last side of the cube and is duct taped to the filters, sealing the system so that air is drawn through the filters and out of the box.
Rosenthal later improved the design by adding a shroud on the fan: this cardboard cutout covers the corners of the box fan to improve the system’s efficiency by reducing backflow.
The units can be assembled in around 15 minutes, last for months, and cost between US$50 and $150 in materials.
Efficacy
Airborne virus particulates range in size from 1 to 50 microns (μm). Rosenthal used his HVAC company's testing equipment to run an informal test of the design, in which he found that around 60% of 1 μm particles were removed by the system, and almost 90% of 10 μm particles were removed. The clean air delivery rate (CADR) of a four-filter, US$75 design were estimated at between per minute (depending on fan speed) in an August 2021 case study by UC Davis researchers. In April 2022, a team based at UC Davis published a study of a Corsi–Rosenthal Box that used five two-inch MERV-13 filters. They found that this design's "effective clean air delivery rate [CADR] increase[d] with fan speed, from about 600 to 850 ft3 min−1 (1019 to 1444 m3 h−1)". Based on the cost of their design, this output amounted to $0.08 per CADR, or roughly ten times cheaper than commercial air purifiers, with quieter operation.
A study of a home-built air purifier to remove wildfire smoke, using a box fan and filter mounted in a window, showed that particulate matter between 1 and 10 μm in size was reduced by about 75%. Wired wrote that this study suggests such filters may effectively filter similarly sized virus particles.
Researchers have expanded studies of these citizen science filtration units to evaluate their efficacy for reducing the levels of airborne volatile chemicals (VOCs); Dodson and colleagues showed the units reduced PFAS and phthalates.
Safety
A 2021 study by Underwriters Laboratories found that attaching filters to a box fan in a do-it-yourself configuration did not present a fire hazard from increased heating of the fan motor windings.
Uses
Corsi–Rosenthal Boxes have been used in schools to reduce risk of COVID-19 transmission, sometimes also functioning as a STEM lesson with students learning about the science of air filtration and constructing the boxes themselves. At the university level, engineering students are also running tests on the units.
Homeless shelters and daycare facilities have also used Corsi–Rosenthal Boxes to mitigate COVID risk.
Corsi–Rosenthal Boxes have also seen use in the 2023 wildfire season in North America, especially as smoke pollution caused hazardous air quality conditions across heavily populated areas in the Eastern United States.
See also
N95 respirator
References
External links
Video of Richard Corsi demonstrating construction of a Corsi–Rosenthal Box, April 15, 2022
Air filters
Indoor air pollution
Scientific and technical responses to the COVID-19 pandemic
Gas technologies | Corsi–Rosenthal Box | [
"Chemistry"
] | 1,285 | [
"Air filters",
"Filters"
] |
59,638,947 | https://en.wikipedia.org/wiki/LAS%20file%20format | The LAS (LASer) format is a file format designed for the interchange and archiving of lidar point cloud data. It is an open, binary format specified by the American Society for Photogrammetry and Remote Sensing (ASPRS). The format is widely used and regarded as an industry standard for lidar data.
File structure
A LAS file consists of the following overall sections:
Point data records
A LAS file contains point records in one of the point data record formats defined by the LAS specification; as of LAS 1.4, there are 11 point data record formats (0 through 10) available. All point data records must be of the same format within the file. The various formats differ in the data fields available, such as GPS time, RGB and NIR color and wave packet information.
The 3D point coordinates are represented within the point data records by 32-bit integers, to which a scaling and offset defined in the public header must be applied in order to obtain the actual coordinates.
As the number of bytes used per point data record is explicitly given in the public header block, it is possible to add user-defined fields in "extra bytes" to the fields given by the specification-defined point data record formats. A standardized way of interpreting such extra bytes was introduced in the LAS 1.4 specification, in the form of a specific EVLR.
Compression
LAS file format is not compressed, but there is an open source project LASzip which defined the open file format LAZ to losslessly compress LAS data.
References
External links
LASer (LAS) File Format Exchange Activities at American Society for Photogrammetry and Remote Sensing
Official ASPRS LAS Page on GitHub
GIS file formats | LAS file format | [
"Technology"
] | 345 | [
"Computing stubs",
"Software stubs"
] |
59,641,664 | https://en.wikipedia.org/wiki/Fe%2C%20Fi%2C%20Fo%2C%20Fum%2C%20and%20Phooey | Fe, Fi, Fo, Fum, and Phooey were five mice who traveled to the Moon and circled it 75 times on the 1972 Apollo 17 mission. NASA gave them identification numbers A3305, A3326, A3352, A3356, and A3400, and their nicknames were given by the Apollo 17 crew (Eugene Cernan, Harrison Schmitt, and Ronald Evans). The four male mice, one female mouse, and Evans orbited the Moon for a record-setting six days and four hours in the Apollo command module America as Cernan and Schmitt performed the Apollo program's last lunar excursions.
The mice travelled in individual compartments of tubes inside an aluminium container with "a sufficient food supply, temperature control, and a reserve of potassium superoxide that absorbed the from their respiration and provided them with fresh oxygen." One of the male mice died (A-3352) during the trip, and the four survivors were euthanized and dissected for their expected biological information upon their return from the Moon.
The three astronauts and the five mice were the last Earthlings to travel to and orbit the Moon. Evans and the five mice share two living-being spaceflight records, the longest amount of time spent in lunar orbit (147 hours 43 minutes), and the most lunar orbits completed (75).
Mission
Apollo 17 launched December 7, 1972, and returned to Earth on December 19. A biological cosmic ray experiment (BIOCORE) carried the five pocket mice (Perognathus longimembris), a species chosen for the experiment because they had well documented biological responses. Some advantages of the species included their small size, ease of maintenance in an isolated state (requiring no drinking water for the expected duration of the mission and producing highly concentrated waste), and their proven capability of withstanding environmental stress.
Fe, Fi, Fo, Fum, and Phooey had been implanted with radiation monitors under their scalps to see whether they would suffer damage from cosmic rays. Four of the five mice survived the flight; the cause of death of the fifth was not determined.
After their return to Earth, the four remaining live mice were euthanized and dissected. Although lesions in the scalp and liver were detected, they appeared to be unrelated to one another and were not thought to be the result of cosmic rays. No damage was found in the mice's retinas or viscera. At the time of the publication of the Apollo 17 Preliminary Science Report the mice's brains had not yet been examined, but subsequent studies showed no significant effect on their brains.
Gallery
See also
Animals in space
Zond 5, a Soviet space program circumlunar voyage in September 1968, by two tortoises and assorted small plants and insects. They were the first Earthlings to fly to the vicinity of the Moon.
Zond 6, turtles on a circumlunar mission in November 1968
Zond 7, four turtles flew the August 1969 circumlunar flight
Fee-fi-fo-fum, the namesake portion of the 1734 English fairy tale "Jack and the Beanstalk"
References
External links
Space exchange, October, 2020
Unilad article, April 28, 2021
Apollo 17
Animals in space
Perognathus
Individual animals in the United States
Individual mice
Cosmic-ray experiments
Space science experiments
Ronald Evans (astronaut)
Animal testing in the United States
Animal deaths by euthanasia
1972 in spaceflight
1972 animal deaths | Fe, Fi, Fo, Fum, and Phooey | [
"Chemistry",
"Biology"
] | 719 | [
"Animal testing",
"Space-flown life",
"Animals in space"
] |
59,642,920 | https://en.wikipedia.org/wiki/NGC%205846 | NGC 5846 is an elliptical galaxy located in the constellation Virgo. It is located at a distance of circa 90 million light years from Earth, which, given its apparent dimensions, means that NGC 5846 is about 110,000 light years across. It was discovered by William Herschel on February 24, 1786. It lies near 110 Virginis and is part of the Herschel 400 Catalogue. It is a member of the NGC 5846 Group of galaxies, itself one of the Virgo III Groups strung out to the east of the Virgo Supercluster of galaxies.
Characteristics
NGC 5846 is a giant elliptical galaxy with a round shape. It has a low luminosity active galactic nucleus, whose categorisation is ambiguous, having features that are observed both in LINER and HII regions. The source of nuclear activity in galaxies is suggested to be a supermassive black hole that accretes material. NGC 5846 harbors a supermassive black hole with estimated mass based on the central velocity dispersion.
NGC 5846 harbors a large number of globular clusters; over 1,200 have been detected in images by Hubble Space Telescope. The specific frequency is similar to other elliptical galaxies in groups. As has been observed in other large elliptical galaxies, the metallicity has bimodial distribution, with metallicities roughly of [Fe/H]=-1.2 and -0.2. Their typical effective radii are in the range of 3 - 5 pc, with the largest clusters located in the central regions. Seven of the globular clusters have X-ray counterparts, which are among the most luminous X-ray sources in NGC 5846. These clusters are mostly in the central region and they are optically luminous, compact and belong to the red subpopulation.
The galaxy has complex X-ray morphology that is considered to be the result of AGN outflows. Two inner bubbles in the hot gas, at a distance of 600 pc from the center and filled with radio emission, are clear indications of recent AGN feedback. A weak radio source, elongated in the NE–SW direction, connects the inner cavities. X-ray-bright rims surround the inner X-ray bubbles. Many X-ray knots are visible, suggesting cooling sites. The scenario indicated by the Chandra observation is that of an AGN outflow, compressing and cooling the gas in the central ~2 kpc (20" at the distance of NGC 5846).
Hα observations reveal the presence of warm ionized gas in the inner 2 kpc of NGC 5846. Spectra of this gas indicate irregular motion, with a typical velocity of 150–200 km s−1. The warm gas traces the X-ray-bright features, again suggesting a multiphase AGN outflow. Using the Spitzer IRS mid-infrared lines were detected (e.g., [Ne ii] 12.81 μm, [Ne iii] 15.55 μm) but no trace of polycyclic aromatic hydrocarbon (PAH) emission. Several sources are identified in the radio at 2.3, 5, and 15 GHz using VLBA data; these sources are aligned in the south–north direction.
Recent Herschel PACS observations have detected the presence of [C ii]-emitting gas that extends to a radius of ~2 kpc and is centrally peaked. The [C ii] emission is almost exactly cospatial with the H-alpha +[N II] emission, and the total fluxes in [C ii] and H-alpha +[N II] have a ratio of 2.5, a very similar flux ratio value observed in other group-centered ellipticals. Furthermore, the velocities inferred from the [C ii] line are consistent with those measured for the Hα line. All of this evidence suggests that the [C ii] line is emitted by the warm gas, and it is not necessarily tracing the molecular phase.
NGC 5846 has another indication that the cold gas is being disturbed by an AGN outburst. It has, in fact, an excess of cold (T ~ 30 K) dust approximately cospatial with the ionized and molecular gas. With a 70 μm luminosity of 3.5 × 1041 erg s−1, NGC 5846 shares the same dust properties as several giant ellipticals (e.g., NGC 4636 and NGC 5044), which are best explained with the ejection of dusty gas from their centers by AGN activity that occurred ~107 yr ago.
Three CO clouds have been detected in NGC 5846. Clouds 1 and 3 are resolved in at least one direction by ALMA 12 m array observations and extend to 1"2 and 2"9, respectively, and are about 5"5 and 8"4 away (0.6 and 1.0 kpc) from the galaxy center, respectively. Cloud 3 is aligned almost exactly along a dust filament, while cloud 1 also coincides with small dust extinction structures. The elongation and potential bimodality of the surface brightness of cloud 3 of NGC 5846 could indicate that it might be composed of two nearby (in projection) clouds. Cloud 2 lies further away from the centre and is thought to originate from cooling in the wakes beneath buoyant X-ray cavities where compressions stimulate significant large-scale, coherent radiative cooling.
Nearby galaxies
NGC 5846 forms a non-interacting pair with NGC 5846A, which lies 0.7 arcminutes from NGC 5846. Its proximity to NGC 5846 and high surface brightness suggests it has been tidally stripped. The barred spiral galaxy NGC 5850 lies at a projected distance of 10 arcminutes from NGC 5846 and may form an interacting pair with NGC 5846 based on its disturbed morphology. It is suggested that the two galaxies had a high speed encounter approximately 200 million years ago.
NGC 5846 has a companion named NGC 5846-UDG1, an example of an ultra diffuse galaxy. Ultra-diffuse galaxies have higher proportions of globular clusters than other galaxies, but NGC 5846 is one of the most extreme, with about 13% of its luminosity coming from globular clusters.
NGC 5846 is the foremost galaxy of the large galaxy group known as the NGC 5846 group. Other members of the group include NGC 5813, NGC 5831, NGC 5845, and NGC 5854. The group has two subgroups, one centered around the elliptical NGC 5813 and the other around NGC 5846, lying at a projected separation of 600 kpc. The group is part of the Virgo III Groups, a very obvious chain of galaxy groups on the left side of the Virgo cluster, stretching across 40 million light years of space.
References
External links
NGC 5846 on SIMBAD
Elliptical galaxies
Virgo (constellation)
5846
09706
53932
Astronomical objects discovered in 1786
Discoveries by William Herschel | NGC 5846 | [
"Astronomy"
] | 1,440 | [
"Virgo (constellation)",
"Constellations"
] |
59,642,940 | https://en.wikipedia.org/wiki/Clara%20Barker | Clara Michelle Barker is a British engineer and material scientist. In 2017 she received the Points of Light award from the UK Prime Minister's Office for her volunteer work raising awareness of lesbian, gay, bisexual and transgender issues. The outcome of this was her rise as a significant role model to the LGBT+ community.
Career and research
Barker completed her thesis on thin film coating at Manchester Metropolitan University. She then held a post-doctoral position at the Swiss Federal Laboratories for Materials Science and Technology (EMPA) in Switzerland for four years, before she moved to the University of Oxford, where she manages the Centre for Applied Superconductivity within the Materials Department. Her current research focuses on creating thin film high temperature superconductors that could be used a resonators for quantum computing devices.
Barker is currently a Daphne Jackson Trust research fellow and Dean for equality and diversity at Linacre College. She is a member of the Royal Society Diversity and Inclusion Committee. She was the vice-chair of the university's LGBT+ Advisory Group. In 2023, she was featured in place of the Seven Sisters tube station in the Engineering Icons Tube Map. In November 2023 she was appointed Inclusion and Diversity Representative by the Institute of Physics, taking over the position from Helen Gleeson.
LGBT+ advocacy
Barker is a transgender woman and an advocate for LGBT+ diversity and women in STEM. She works with a youth group in Oxfordshire, TOPAZ. She has also spoken local schools on behalf of Stonewall and has helped Oxford City Council run an anti-HBT bullying initiative. In 2017, she was featured in a Stonewall poster campaign for Trans Day of Visibility. She also led the promotion of the Out in Oxford project, a project which highlights LGBT+ artefacts in museums. She has given numerous talks on LGBT+ visibility and diversity in STEM. In December 2018 Barker gave a TEDx talk entitled "Why we need to build trust to create diversity in institutions". She has also appeared on BBC Victoria Derbyshire and Sky News talking about transgender rights.
Barker has received several awards for her advocacy. In 2017 she was the 795th person to receive the Points of Light award for her work with Out in Oxford her other volunteering. Her belief is that role models are necessary in all aspects of life. Her representation in STEM has been pivotal for following generations to follow in her footsteps.
In 2018, she won the staff Individual Champion/Role Model award in the Vice-Chancellor's Diversity Awards from the University of Oxford.
References
21st-century British women scientists
21st-century British engineers
Alumni of Manchester Metropolitan University
British materials scientists
British women activists
British women academics
British women's rights activists
Living people
British LGBTQ rights activists
British LGBTQ scientists
People associated with Linacre College, Oxford
Superconductivity scientists and engineers
Transgender academics
British transgender women
Transgender scientists
Women materials scientists and engineers
Year of birth missing (living people)
British women civil rights activists
21st-century British LGBTQ people | Clara Barker | [
"Materials_science",
"Technology"
] | 596 | [
"Women materials scientists and engineers",
"Materials scientists and engineers",
"Women in science and technology"
] |
59,645,152 | https://en.wikipedia.org/wiki/NGC%20779 | NGC 779 is a spiral galaxy seen edge-on, located in the constellation Cetus. It is located at a distance of circa 60 million light years from Earth, which, given its apparent dimensions, means that NGC 779 is about 70,000 light years across. It was discovered by William Herschel on September 10, 1785.
NGC 779 features a bright nucleus and an elliptical or boxy bulge. It is seen with high inclination. The inner arms are tightly wound and form an inner pseudoring with high surface brightness. A break is seen at the northwest side of the pseudoring and may be due to dust extinction. The disk has lower surface brightness and is smooth, with no pronounced star-forming knots. The spiral pattern of the galaxy gas been described either as multiple-armed or grand-design two-armed spiral.
NGC 779 forms a small galaxy group with UGCA 024, known as the NGC 779 group. NGC 779 is considered to be part of the Cetus II cloud, which also includes NGC 584, NGC 681, NGC 720, and their groups, although it could also lie in the foreground.
The galaxy is included in the Herschel 400 Catalogue. It lies about five degrees northeast from Zeta Ceti. It can be seen with a small telescope at moderate magnification, with its core being more easily detected.
References
External links
NGC 779 on SIMBAD
Spiral galaxies
Cetus
0779
007544
Astronomical objects discovered in 1785
Discoveries by William Herschel | NGC 779 | [
"Astronomy"
] | 309 | [
"Cetus",
"Constellations"
] |
59,645,341 | https://en.wikipedia.org/wiki/World%20Is%20Not%20Enough%20%28spacecraft%20propulsion%29 | The World Is Not Enough (WINE) is a US project developing a refuelable steam engine system for spacecraft propulsion. WINE developed a method of extracting volatiles from ice, ice-rich regolith, and hydrated soils and uses it as steam propulsion which allows the spacecraft to refuel multiple times and have an extraordinary long service lifetime. This would allow a single spacecraft to visit multiple asteroids, comets or several landing locations at an icy world such as the Moon, Mars, Pluto, Enceladus, Ganymede, Europa, etc.
The harvesting and propulsion systems were successfully tested in December 2018 on a small spacecraft prototype under simulated asteroid conditions. WINE is a joint project of Honeybee Robotics, the University of Central Florida, and Embry–Riddle Aeronautical University in Florida.
Overview
WINE is a joint project of Honeybee Robotics, the University of Central Florida (UCF), and Embry–Riddle Aeronautical University (ERAU) in Florida, meant to facilitate in situ resource utilization (ISRU) of water as a critical part of sustainable and cost-effective space exploration. WINE was conceived by planetary research scientist Philip Metzger at the University of Central Florida and Kris Zacny of Honeybee Robotics.
The team developed and tested a spacecraft prototype that harvests local water ice "for eternal exploration of space" using steam as propulsion. The system employs a drill to mine and extract water ice from the surface soil (regolith), purify the water, and heat it to be used as compressed steam for propulsion. Refueling can be repeated indefinitely at different icy bodies within the Solar System or at multiple landing sites at icy worlds with low gravity such as Pluto, Enceladus, Europa, and the Moon.
As of January 2019, development and testing are funded by NASA's Small Business Innovation Research program (SIBIR).
General description
There are two versions of water harvesters being developed by Honeybee Robotics: the 'Spider System' is for landers meant to "walk" or takeoff again using steam power, and PVEx for large rovers meant to harvest and transport the water for other purposes. The water extracted is stored in a tank, and it can be used for steam propulsion or can be transported elsewhere for other uses.
The Spider Water Extraction System features multiple systems integrated into spacecraft lander legs to provide higher processing volume and system redundancy. It can drill into cemented icy and mineral composites that can be as hard as concrete. The architecture enables each drill to also act as an anchoring force as they sample for water-rich material. The stored water can be heated into steam and used to move the lander's legs as a spider does for walking, or use it as a jet thrust to fly to different landing sites or to travel to multiple icy bodies.
The Planetary Volatiles Extractor (PVEx) is a variant best mounted on a large rover equipped with radioisotope thermoelectric generators. It features a double-walled coring auger with a heated inner wall to extract volatiles from ice, ice-rich regolith, and hydrated soils from icy bodies. The double-wall coring drill penetrates icy material and heats the volatile-rich core, causing water and other volatiles to turn into a gas. This gas is contained in the system and flows into a cold trap, where it condenses into a solid and can be transferred to a storage tank on another vehicle or depot. The system combines mining and extraction into one step. It drills to a target depth, obtains a core sample, heats it up, and captures volatiles in a condenser above the surface. Once extraction is complete, the corer is retracted and the dry regolith core is left behind.
Testing
Initial tests in 2016 were performed in limestone and blocks of ice to evaluate mechanical aspects of the system. The PVEx variant targeted a depth of in limestone in 10 minutes and a similar depth in ice blocks in 7 minutes. Early performance tests under space analog conditions measured a water extraction efficiency of 87% while requiring extraction energy of 1.7 Whr/g; the needed power is 60 watts for 40 minutes. To harvest 30 kg of water per day, the PVEx corer would need two MMRTG generators. For lower demands, it can use solar panels.
Later in 2016, the team experimented with several mining mechanisms that were adapted to the smaller size of a WINE spacecraft. The mining tests extracted water from lunar regolith simulant that contained ice. The tests also extracted water from asteroid regolith simulant that was physically dry (containing no water or ice), because it released the water that had been locked inside the crystalline structure of its phyllosilicate minerals. Phyllosilicates are abundant in carbonaceous asteroids. This extracted asteroidal water was found to contain large amounts of dissolved carbon dioxide, metals, and organic matter due to the bulk composition of the simulated asteroid, but the team did not consider this a hindrance to steam propulsion. Based on the results, they selected the PVEX corer for additional development in an integrated WINE prototype.
The team successfully tested the integrated prototype on 31 December 2018 under simulated outer space conditions of vacuum and low temperature while harvesting frozen water from simulated asteroid regolith. Within minutes, the microwave-sized spacecraft extracted the water from hydrated artificial regolith and took off within the vacuum chamber using steam thrusters.
The system components are expected to reach technology readiness level 5 (TRL 5) in 2019. Although the research is funded by NASA, this water-harvesting system is available to private companies to use it on asteroids, comets, the Moon, Ceres, Europa, Titan, Pluto, the poles of Mercury, or anywhere there is water and sufficiently low gravity.
Power
The spacecraft uses deployable solar panels to generate electrical energy for mining and making steam, or it could use radioisotope thermoelectric generators (RTG) to extend the potential reach of these planetary hoppers to Pluto and other locations far from the Sun. The water is heated and allowed to escape as pressurized steam through a propelling nozzle to produce thrust. Alternatively, the steam is used to initiate mechanical movement as a steam engine.
See also
Asteroidal water
Lunar water
Spacecraft propulsion
Steam rocket
Water on Mars
Water on terrestrial planets of the Solar System
References
Asteroid mining
Extraterrestrial water
Industry in space
Mining in space
Mining techniques
Natural resources
Spacecraft propulsion
Space manufacturing
Steam power | World Is Not Enough (spacecraft propulsion) | [
"Physics",
"Astronomy"
] | 1,319 | [
"Industry in space",
"Physical quantities",
"Outer space",
"Steam power",
"Power (physics)"
] |
59,645,446 | https://en.wikipedia.org/wiki/Haploviricotina | Haploviricotina is a subphylum of viruses in the phylum Negarnaviricota. It is one of only two virus subphyla, the other being Polyploviricotina, which is also in Negarnaviricota. The name comes from , the Ancient Greek for 'simple', along with the suffix for a virus subphylum; 'viricotina'.
Taxonomy
The subphylum Haploviricotina is composed of 4 classes and 5 orders:
Chunqiuviricetes
Muvirales
Milneviricetes
Serpentovirales
Monjiviricetes
Jingchuvirales
Mononegavirales
Yunchangviricetes
Goujianvirales
References
Negarnaviricota
Virus subphyla | Haploviricotina | [
"Biology"
] | 162 | [
"Virus stubs",
"Viruses"
] |
59,645,482 | https://en.wikipedia.org/wiki/K2-19 | K2-19 is an early K-type or late G-type main sequence star that is magnetically active, and has a light curve that exhibits variations in brightness of ~1%. It is located approximately 976 light-years away in the constellation Virgo. Three confirmed transiting exoplanets are known to orbit this star.
Planetary system
Discovery
The two outer planets were reported as planet candidates during analysis of data from Campaign 1 of the Kepler space telescope's K2 extended mission. Both planets were confirmed by David J. Armstrong and collaborators, who used ground-based telescopes to detect additional transits and measure hour-long transit-timing variations for K2-19b. They were independently validated along with 20 other planets by Benjamin T. Montet and team.
K2-19d was first reported as a planet candidate during a search for candidates from the first year of the K2 Mission and was later validated by Sinukoff et al.
Characteristics
K2-19 has a planetary system with three known planets, of which the two larger ones, K2-19b and K2-19c, are close to the 3:2 mean motion resonance. All three planets orbit closer to their star than the planet Mercury does to the Sun.
References
K-type main-sequence stars
Planetary systems with three confirmed planets
Planetary transit variables
Virgo (constellation) | K2-19 | [
"Astronomy"
] | 282 | [
"Virgo (constellation)",
"Constellations"
] |
59,645,501 | https://en.wikipedia.org/wiki/Polyploviricotina | Polyploviricotina is a subphylum of viruses in the phylum Negarnaviricota. It is one of only two virus subphyla, the other being Haploviricotina, which is also in Negarnaviricota. The name comes from , the Ancient Greek for 'complex', along with the suffix for a virus subphylum; 'viricotina'.
References
External links
Invasion of the Body Snatchers: Viruses Can Steal Our Genetic Code to Create New Human-Virus Genes; on: SciTechDaily, Source: Mount Sinai School of Medicine; August 9, 2020
Jessica Sook Yuin Ho, Matthew Angel, Yixuan Ma, Jonathan W. Yewdell, Edward Hutchinson, Ivan Marazzi, et al.: Hybrid Gene Origination Creates Human-Virus Chimeric Proteins during Infection; in: Cell Volume 181, Issue 7; June 18, 2020; doi:10.1016/j.cell.2020.05.035
Yixuan Ma, Matthew Angel, Guojun Wang, Jessica Sook Yuin Ho, Nan Zhao, Justine Noel, Natasha Moshkina, et al.: Discovery of UFO Proteins: Human-Virus Chimeric Proteins Generated During Influenza Virus Infection; on: bioRxiv; April 8, 2019; doi:10.1101/597617
Negarnaviricota
Virus subphyla | Polyploviricotina | [
"Biology"
] | 295 | [
"Virus stubs",
"Viruses"
] |
59,646,351 | https://en.wikipedia.org/wiki/Fine-grained%20reduction | In computational complexity theory, a fine-grained reduction is a transformation from one computational problem to another, used to relate the difficulty of improving the time bounds for the two problems.
Intuitively, it provides a method for solving one problem efficiently by using the solution to the other problem as a subroutine.
If problem can be solved in time and problem can be solved in time , then the existence of an -reduction from problem to problem implies that any significant speedup for problem would also lead to a speedup for problem .
Definition
Let and be computational problems, specified as the desired output for each possible input.
Let and both be time-constructible functions that take an integer argument and produce an integer result. Usually, and are the time bounds for known or naive algorithms for the two problems, and often they are monomials such as .
Then is said to be -reducible to
if, for every real number , there exists a real number and an algorithm that solves instances of problem by transforming it into a sequence of instances of problem , taking time for the transformation on instances of size , and producing a sequence of instances whose sizes are bounded by .
An -reduction is given by the mapping from to the pair of an algorithm and .
Speedup implication
Suppose is -reducible to , and there exists such that can be solved in time .
Then, with these assumptions, there also exists such that can be solved in time . Namely, let be the value given by the -reduction, and solve by applying the transformation of the reduction and using the fast algorithm for for each resulting subproblem.
Equivalently, if cannot be solved in time significantly faster than , then cannot be solved in time significantly faster than .
History
Fine-grained reductions were defined, in the special case that and are equal monomials, by Virginia Vassilevska Williams and Ryan Williams in 2010.
They also showed the existence of -reductions between several problems including all-pairs shortest paths, finding the second-shortest path between two given vertices in a weighted graph, finding negative-weight triangles in weighted graphs, and testing whether a given distance matrix describes a metric space. According to their results, either all of these problems have time bounds with exponents less than three, or none of them do.
The term "fine-grained reduction" comes from later work by Virginia Vassilevska Williams in an invited presentation at the 10th International Symposium on Parameterized and Exact Computation.
Although the original definition of fine-grained reductions involved deterministic algorithms, the corresponding concepts for randomized algorithms and nondeterministic algorithms have also been considered.
References
Reduction (complexity) | Fine-grained reduction | [
"Mathematics"
] | 539 | [
"Reduction (complexity)",
"Functions and mappings",
"Mathematical relations",
"Mathematical objects"
] |
59,648,370 | https://en.wikipedia.org/wiki/Redmi%20Note%207 | The Redmi Note 7 series refer to a series of smartphones released by Redmi, a sub-brand of Xiaomi. All (except the Redmi Note 7 variant in India) have 48 MP + 5 MP camera sensors. Most have a Qualcomm Snapdragon 660 SoC, except the Redmi Note 7 Pro, which has a better Qualcomm Snapdragon 675 SoC. The phones support mobile network frequencies in different regions. The Note 7 is available in many local versions and a global version, compatible with mobile phone providers in most places; the Pro model is supplied in slightly different Chinese and Indian versions. The Redmi Note 7S doesn't have much difference when compared to Redmi Note 7 except in case of the rear camera, hence the production of the Redmi Note 7S was discontinued and came under the Redmi Note 7 in India but it's still available separately in China and other countries.
In August 2019 Xiaomi announced that the Redmi Note 7 series had sold more than 20 million units worldwide.
Specifications
The Redmi Note 7 (lavender) is available in versions M1901F7C (for Hong Kong), 1901F7E (for China), 1901F7G (global), and 1901F7H (for Asia).
Design
The Redmi Note 7 (and Note 7 Pro) features a shiny glass back with a gradient that Xiaomi calls "Aura Design". Both the front and back of the device have 2.5D curved Gorilla Glass 5 glass. The phone also has a P2i nano-coating that makes it splash resistant, nevertheless the phone hasn't received an official IP Code. In other markets such as India, available color variants include Nebula Red, Space Black, and Neptune Blue.
The Redmi Note 7 (and Note 7 Pro) also features a dot notch in the display to accommodate the front-facing camera.
Software
The Redmi Note 7 and Pro run on Xiaomi's MIUI version 10, based on Android Pie (9), with minor version updates from time to time. Xiaomi has confirmed that these phones will be upgraded to Android 10; unofficial information suggests that this will be done in the third quarter of 2020. Updates to MIUI 11 (based on Android 9) for the Redmi Note 7 and the Redmi Note 7 Pro were available for download in late 2019, though not yet distributed over the air (OTA) for some ROM versions. From 19 November 2020, MIUI 12 based on Android 10 was being rolled out to Redmi Note 7/7s, with distribution to other phones after beta testing.
Hardware
The Redmi Note 7 (lavender) and Note 7 Pro (violet), both have a 6.3-inch full HD+ (2340×1080 pixels) display with a 19.5:9 aspect ratio. The Redmi Note 7 is powered by a 14 nm octa-core Snapdragon 660 SoC while the Note 7 Pro houses a Snapdragon 675 SoC, making it the first Xiaomi device to use the chip. The RN7 has an Adreno 512 GPU (612 for the Pro variant) and a 4000 mAh battery and supports Quick Charge 4. Various versions are fitted with 3, 4, or 6 GB of RAM, with 32, 64, or 128 GB of storage; a micro SD card of up to 256 GB is supported via a hybrid SIM card slot. The Pro version's camera has a Sony IMX586 sensor with f/1.8 aperture, slightly better than the RN7's similarly specified Samsung ISOCELL GM1 sensor; both have a secondary 5-megapixel depth sensor. The front camera has a resolution of 13 megapixels. The rear camera can record 4K video at 30 fps.
The RN7 Pro has a studio lighting mode live option, showing what the studio lighting effect will look like.
The phone has AI scene detection capable of recognizing up to 12 scenes, AI Portrait 2.0 and a Night Mode.
Connectivity
The Redmi Note 7 (and Note 7 Pro) supports Wi-Fi 802.11 a/b/g/n/ac, satellite navigation, Bluetooth v5.0, USB OTG, USB Type-C, 3G and 4G networks (with support for Band 40 used by some LTE networks in India), and VoLTE.
Other features
The phone has a gyroscope, proximity sensor, and fingerprint sensor. It has two Nano-SIM slots; one of them is a hybrid, capable of holding either a SIM or a microSD card. Either slot can, if equipped with a SIM, can be configured as the primary one.
Among other features, there is FM radio with recording, USB type-C, Dual SIM, face unlock, notification LED etc.
An IR blaster, emulating an infrared remote control, and a 3.5 mm headphone jack are fitted.
Release
The Chinese version of Redmi Note 7 was launched in Beijing on 15 January 2019.
The Indian versions of Redmi Note 7 and Redmi Note 7 Pro were launched together in New Delhi, India on 28 February 2019.
The Global version of Redmi Note 7 was launched on 6 March 2019.
The Chinese version of Redmi Note 7 Pro was launched on 18 March 2019.
There will not be a global version of the Redmi Note 7 Pro.
The Indian version of Redmi Note 7S was launched on 20 May 2019.
Rear camera images
References
External links
Official site (global version)
Specifications from GSM Arena
Phablets
Note 7
Ubuntu Touch devices
Mobile phones introduced in 2019
Mobile phones with multiple rear cameras
Mobile phones with infrared transmitter
Discontinued smartphones | Redmi Note 7 | [
"Technology"
] | 1,174 | [
"Crossover devices",
"Phablets"
] |
59,652,617 | https://en.wikipedia.org/wiki/K-outerplanar%20graph | In graph theory, a k-outerplanar graph is a planar graph that has a planar embedding in which the vertices belong to at most concentric layers. The outerplanarity index of a planar graph is the minimum value of for which it is -outerplanar.
Definition
An outerplanar graph (or 1-outerplanar graph) has all of its vertices on the unbounded (outside) face of the graph. A 2-outerplanar graph is a planar graph with the property that, when the vertices on the unbounded face are removed, the remaining vertices all lie on the newly formed unbounded face. And so on.
More formally, a graph is -outerplanar if it has a planar embedding such that, for every vertex, there is an alternating sequence of at most faces and vertices of the embedding, starting with the unbounded face and ending with the vertex, in which each consecutive face and vertex are incident to each other.
Properties and applications
The -outerplanar graphs have treewidth at most . However, some bounded-treewidth planar graphs such as the nested triangles graph may be -outerplanar only for very large , linear in the number of vertices.
Baker's technique covers a planar graph with a constant number of -outerplanar graphs and uses their low treewidth in order to quickly approximate several hard graph optimization problems.
In connection with the GNRS conjecture on metric embedding of minor-closed graph families, the -outerplanar graphs are one of the most general classes of graphs for which the conjecture has been proved.
A conjectured converse of Courcelle's theorem, according to which every graph property recognizable on graphs of bounded treewidth by finite state tree automata is definable in the monadic second-order logic of graphs, has been proven for the -outerplanar graphs.
Recognition
The smallest value of for which a given graph is -outerplanar (its outerplanarity index) can be computed in quadratic time.
References
Planar graphs | K-outerplanar graph | [
"Mathematics"
] | 454 | [
"Planes (geometry)",
"Planar graphs"
] |
59,652,628 | https://en.wikipedia.org/wiki/GNRS%20conjecture | In theoretical computer science and metric geometry, the GNRS conjecture connects the theory of graph minors, the stretch factor of embeddings, and the approximation ratio of multi-commodity flow problems. It is named after Anupam Gupta, Ilan Newman, Yuri Rabinovich, and Alistair Sinclair, who formulated it in 2004.
Formulation
One formulation of the conjecture involves embeddings of the shortest path distances of weighted undirected graphs into spaces, real vector spaces in which the distance between two vectors is the sum of their coordinate differences. If an embedding maps all pairs of vertices with distance to pairs of vectors with distance in the range then its stretch factor or distortion is the ratio ; an isometry has stretch factor one, and all other embeddings have greater stretch factor.
The graphs that have an embedding with at most a given distortion are closed under graph minor operations, operations that delete vertices or edges from a graph or contract some of its edges. The GNRS conjecture states that, conversely, every minor-closed family of graphs, other than the family of all graphs, can be embedded into an space with bounded distortion. That is, the distortion of graphs in the family is bounded by a constant that depends on the family but not on the individual graphs. For instance, the planar graphs are closed under minors. Therefore, it would follow from the GNRS conjecture that the planar graphs have bounded distortion.
An alternative formulation involves analogues of the max-flow min-cut theorem for undirected multi-commodity flow problems. The ratio of the maximum flow to the minimum cut, in such problems, is known as the flow-cut gap. The largest flow-cut gap that a flow problem can have on a given graph equals the distortion of the optimal embedding of the graph. Therefore, the GNRS conjecture can be rephrased as stating that the minor-closed families of graphs have bounded flow-cut gap.
Related results
Arbitrary -vertex graphs (indeed, arbitrary -point metric spaces) have embeddings with distortion . Some graphs have logarithmic flow-cut gap, and in particular this is true for a multicommodity flow with every pair of vertices having equal demand on a bounded-degree expander graph. Therefore, this logarithmic bound on the distortion of arbitrary graphs is tight. Planar graphs can be embedded with smaller distortion, .
Although the GNRS conjecture remains unsolved, it has been proven for some minor-closed graph families that bounded-distortion embeddings exist. These include the series–parallel graphs and the graphs of bounded circuit rank, the graphs of bounded pathwidth, the 2-clique-sums of graphs of bounded size, and the -outerplanar graphs.
In contrast to the behavior of metric embeddings into spaces, every finite metric space has embeddings into with stretch arbitrarily close to one by the Johnson–Lindenstrauss lemma, and into spaces with stretch exactly one by the tight span construction.
See also
Partial cube, a class of graphs with distortion-free unweighted -embeddings
References
Approximation algorithms
Conjectures
Unsolved problems in graph theory
Graph minor theory
Metric geometry | GNRS conjecture | [
"Mathematics"
] | 669 | [
"Unsolved problems in mathematics",
"Approximation algorithms",
"Graph theory",
"Conjectures",
"Unsolved problems in graph theory",
"Mathematical relations",
"Mathematical problems",
"Graph minor theory",
"Approximations"
] |
59,653,118 | https://en.wikipedia.org/wiki/NGC%201381 | NGC 1381 is a lenticular galaxy located in the constellation Fornax. It is located at a distance of about 60 million light years from Earth, which, given its apparent dimensions, means that NGC 1381 is about 55,000 light years across. It is a member of the Fornax Cluster. NGC 1381 appears edge-on and features a thin disk with high surface brightness and a boxy bulge. Both the box-shaped bulge and the kinematics of the central area of the galaxy suggest that NGC 1381 has a bar.
NGC 1381 was discovered by Johann Friedrich Julius Schmidt on January 19, 1865. Julius Schmidt was then director of the National Observatory of Athens and he was inspecting the Cape catalogue nebulae with a 6 ft refractor. Along with NGC 1381, he also discovered the nearby galaxies NGC 1382, NGC 1386, NGC 1389, and NGC 1428. The publication of their discovery was delayed by 10 years and was published in 1876 with the work Über einige im Cape-Catalog fehlende Nebel.
NGC 1381 lies at the core of the Fornax Cluster. It lies within a region with increased density of candidate globular clusters nearly half a degree across that connects the elliptical galaxy NGC 1399 with its surrounding galaxies like NGC 1404, NGC 1387, and NGC 1380B. This structure is considered to be the result of the interactions between the cluster galaxies. A region with intracluster light has also being discovered between NGC 1381, NGC 1387, and NGC 1379. It is suggested that it was created by the tidal stripping of stars and globular clusters from the galaxies.
One supernova has been observed in NGC 1381: SN 2022ffv (Type Ia, mag 13.3).
References
External links
NGC 1381 on SIMBAD
Lenticular galaxies
Fornax
Fornax Cluster
1381
13321
Astronomical objects discovered in 1865
Discoveries by Johann Friedrich Julius Schmidt | NGC 1381 | [
"Astronomy"
] | 404 | [
"Fornax",
"Constellations"
] |
59,654,517 | https://en.wikipedia.org/wiki/Graph%20cut%20optimization | Graph cut optimization is a combinatorial optimization method applicable to a family of functions of discrete variables, named after the concept of cut in the theory of flow networks. Thanks to the max-flow min-cut theorem, determining the minimum cut over a graph representing a flow network is equivalent to computing the maximum flow over the network. Given a pseudo-Boolean function , if it is possible to construct a flow network with positive weights such that
each cut of the network can be mapped to an assignment of variables to (and vice versa), and
the cost of equals (up to an additive constant)
then it is possible to find the global optimum of in polynomial time by computing a minimum cut of the graph. The mapping between cuts and variable assignments is done by representing each variable with one node in the graph and, given a cut, each variable will have a value of 0 if the corresponding node belongs to the component connected to the source, or 1 if it belong to the component connected to the sink.
Not all pseudo-Boolean functions can be represented by a flow network, and in the general case the global optimization problem is NP-hard. There exist sufficient conditions to characterise families of functions that can be optimised through graph cuts, such as submodular quadratic functions. Graph cut optimization can be extended to functions of discrete variables with a finite number of values, that can be approached with iterative algorithms with strong optimality properties, computing one graph cut at each iteration.
Graph cut optimization is an important tool for inference over graphical models such as Markov random fields or conditional random fields, and it has applications in computer vision problems such as image segmentation, denoising, registration and stereo matching.
Representability
A pseudo-Boolean function is said to be representable if there exists a graph with non-negative weights and with source and sink nodes and respectively, and there exists a set of nodes such that, for each tuple of values assigned to the variables, equals (up to a constant) the value of the flow determined by a minimum cut of the graph such that if and if .
It is possible to classify pseudo-Boolean functions according to their order, determined by the maximum number of variables contributing to each single term. All first order functions, where each term depends upon at most one variable, are always representable. Quadratic functions
are representable if and only if they are submodular, i.e. for each quadratic term the following condition is satisfied
Cubic functions
are representable if and only if they are regular, i.e. all possible binary projections to two variables, obtained by fixing the value of the remaining variable, are submodular. For higher-order functions, regularity is a necessary condition for representability.
Graph construction
Graph construction for a representable function is simplified by the fact that the sum of two representable functions and is representable, and its graph is the union of the graphs and representing the two functions. Such theorem allows to build separate graphs representing each term and combine them to obtain a graph representing the entire function.
The graph representing a quadratic function of variables contains vertices, two of them representing the source and sink and the others representing the variables. When representing higher-order functions, the graph contains auxiliary nodes that allow to model higher-order interactions.
Unary terms
A unary term depends only on one variable and can be represented by a graph with one non-terminal node and one edge with weight if , or with weight if .
Binary terms
A quadratic (or binary) term can be represented by a graph containing two non-terminal nodes and . The term can be rewritten as
with
In this expression, the first term is constant and it is not represented by any edge, the two following terms depend on one variable and are represented by one edge, as shown in the previous section for unary terms, while the third term is represented by an edge with weight (submodularity guarantees that the weight is non-negative).
Ternary terms
A cubic (or ternary) term can be represented by a graph with four non-terminal nodes, three of them (, and ) associated to the three variables plus one fourth auxiliary node . A generic ternary term can be rewritten as the sum of a constant, three unary terms, three binary terms, and a ternary term in simplified form. There may be two different cases, according to the sign of . If then
with
If the construction is similarly, but the variables will have opposite value. If the function is regular, then all its projections of two variables will be submodular, implying that , and are positive and then all terms in the new representation are submodular.
In this decomposition, the constant, unary and binary terms can be represented as shown in the previous sections. If the ternary term can be represented with a graph with four edges , , , , all with weight , while if the term can be represented by four edges , , , with weight .
Minimum cut
After building a graph representing a pseudo-Boolean function, it is possible to compute a minimum cut using one among the various algorithms developed for flow networks, such as Ford–Fulkerson, Edmonds–Karp, and Boykov–Kolmogorov algorithm. The result is a partition of the graph in two connected components and such that and , and the function attains its global minimum when for each such that the corresponding node , and for each such that the corresponding node .
Max-flow algorithms such as Boykov–Kolmogorov's are very efficient in practice for sequential computation, but they are difficult to parallelise, making them not suitable for distributed computing applications and preventing them from exploiting the potential of modern CPUs. Parallel max-flow algorithms were developed, such as push-relabel and jump-flood, that can also take advantage of hardware acceleration in GPGPU implementations.
Functions of discrete variables with more than two values
The previous construction allows global optimization of pseudo-Boolean functions only, but it can be extended to quadratic functions of discrete variables with a finite number of values, in the form
where and . The function represents the unary contribution of each variable (often referred as data term), while the function represents binary interactions between variables (smoothness term). In the general case, optimization of such functions is a NP-hard problem, and stochastic optimization methods such as simulated annealing are sensitive to local minima and in practice they can generate arbitrarily sub-optimal results. With graph cuts it is possible to construct move-making algorithms that allow to reach in polynomial time a local minima with strong optimality properties for a wide family of quadratic functions of practical interest (when the binary interaction is a metric or a semimetric), such that the value of the function in the solution lies within a constant and known factor from the global optimum.
Given a function with , and a certain assignment of values to the variables, it is possible to associate each assignment to a partition of the set of variables, such that, . Give two distinct assignments and and a value , a move that transforms into is said to be an -expansion if and . Given a couple of values and , a move is said to be an -swap if . Intuitively, an -expansion move from assigns the value of to some variables that have a different value in , while an -swap move assigns to some variables that have value in and vice versa.
For each iteration, the -expansion algorithm computes, for each possible value , the minimum of the function among all assignments that can be reached with a single -expansion move from the current temporary solution , and takes it as the new temporary solution.
while :
foreach :
if :
The -swap algorithm is similar, but it searches for the minimum among all assignments reachable with a single -swap move from .
while :
foreach :
if :
In both cases, the optimization problem in the innermost loop can be solved exactly and efficiently with a graph cut. Both algorithms terminate certainly in a finite number of iterations of the outer loop, and in practice such number is small, with most of the improvement happening at the first iteration. The algorithms can generate different solutions depending on the initial guess, but in practice they are robust with respect to initialisation, and starting with a point where all variables are assigned to the same random value is usually sufficient to produce good quality results.
The solution generated by such algorithms is not necessarily a global optimum, but it has strong guarantees of optimality. If is a metric and is a solution generated by the -expansion algorithm, or if is a semimetric and is a solution generated by the -swap algorithm, then lies within a known and constant factor from the global minimum :
Non-submodular functions
Generally speaking, the problem of optimizing a non-submodular pseudo-Boolean function is NP-hard and cannot be solved in polynomial time with a simple graph cut. The simplest approach is to approximate the function with a similar but submodular one, for instance truncating all non-submodular terms or replacing them with similar submodular expressions. Such approach is generally sub-optimal, and it produces acceptable results only if the number of non-submodular terms is relatively small.
In case of quadratic non-submodular functions, it is possible to compute in polynomial time a partial solution using algorithms such as QPBO. Higher-order functions can be reduced in polynomial time to a quadratic form that can be optimised with QPBO.
Higher-order functions
Quadratic functions are extensively studied and were characterised in detail, but more general results were derived also for higher-order functions. While quadratic functions can indeed model many problems of practical interest, they are limited by the fact they can represent only binary interactions between variables. The possibility to capture higher-order interactions allows to better capture the nature of the problem and it can provide higher quality results that could be difficult to achieve with quadratic models. For instance in computer vision applications, where each variable represents a pixel or voxel of the image, higher-order interactions can be used to model texture information, that would be difficult to capture using only quadratic functions.
Sufficient conditions analogous to submodularity were developed to characterise higher-order pseudo-Boolean functions that can be optimised in polynomial time, and there exists algorithms analogous to -expansion and -swap for some families of higher-order functions. The problem is NP-hard in the general case, and approximate methods were developed for fast optimization of functions that do not satisfy such conditions.
Notes
References
Bibliography
External links
Implementation (C++) of several graph cut algorithms by Vladimir Kolmogorov.
GCO, graph cut optimization library by Olga Veksler and Andrew Delong.
Combinatorial optimization
Computer vision
Computational problems in graph theory | Graph cut optimization | [
"Mathematics",
"Engineering"
] | 2,234 | [
"Computational problems in graph theory",
"Packaging machinery",
"Computational mathematics",
"Graph theory",
"Computational problems",
"Mathematical relations",
"Artificial intelligence engineering",
"Mathematical problems",
"Computer vision"
] |
59,654,519 | https://en.wikipedia.org/wiki/Quadratic%20pseudo-Boolean%20optimization | Quadratic pseudo-Boolean optimisation (QPBO) is a combinatorial optimization method for minimizing quadratic pseudo-Boolean functions in the form
in the binary variables , with . If is submodular then QPBO produces a global optimum equivalently to graph cut optimization, while if contains non-submodular terms then the algorithm produces a partial solution with specific optimality properties, in both cases in polynomial time.
QPBO is a useful tool for inference on Markov random fields and conditional random fields, and has applications in computer vision problems such as image segmentation and stereo matching.
Optimization of non-submodular functions
If the coefficients of the quadratic terms satisfy the submodularity condition
then the function can be efficiently optimised with graph cut optimization. It is indeed possible to represent it with a non-negative weighted graph, and the global minimum can be found in polynomial time by computing a minimum cut of the graph, which can be computed with algorithms such as Ford–Fulkerson, Edmonds–Karp, and Boykov–Kolmogorov's.
If the function is not submodular, then the problem is NP-hard in the general case and it is not always possible to solve it exactly in polynomial time. It is possible to replace the target function with a similar but submodular approximation, e.g. by removing all non-submodular terms or replacing them with submodular approximations, but such approach is generally sub-optimal and it produces satisfying results only if the number of non-submodular terms is relatively small.
QPBO builds an extended graph, introducing a set of auxiliary variables ideally equivalent to the negation of the variables in the problem. If the nodes in the graph associated to a variable (representing the variable itself and its negation) are separated by the minimum cut of the graph in two different connected components, then the optimal value for such variable is well defined, otherwise it is not possible to infer it. Such method produces results generally superior to submodular approximations of the target function.
Properties
QPBO produces a solution where each variable assumes one of three possible values: true, false, and undefined, noted in the following as 1, 0, and respectively. The solution has the following two properties.
Partial optimality: if is submodular, then QPBO produces a global minimum exactly, equivalent to graph cut, and all variables have a non-undefined value; if submodularity is not satisfied, the result will be a partial solution where a subset of the variables have a non-undefined value. A partial solution is always part of a global solution, i.e. there exists a global minimum point for such that for each .
Persistence: given a solution generated by QPBO and an arbitrary assignment of values to the variables, if a new solution is constructed by replacing with for each , then .
Algorithm
The algorithm can be divided in three steps: graph construction, max-flow computation, and assignment of values to the variables.
When constructing the graph, the set of vertices contains the source and sink nodes and , and a pair of nodes and for each variable. After re-parametrising the function to normal form, a pair of edges is added to the graph for each term :
for each term the edges and , with weight ;
for each term the edges and , with weight ;
for each term the edges and , with weight ;
for each term the edges and , with weight ;
for each term the edges and , with weight ;
for each term the edges and , with weight .
The minimum cut of the graph can be computed with a max-flow algorithm. In the general case, the minimum cut is not unique, and each minimum cut correspond to a different partial solution, however it is possible to build a minimum cut such that the number of undefined variables is minimal.
Once the minimum cut is known, each variable receives a value depending upon the position of its corresponding nodes and : if belongs to the connected component containing the source and belongs to the connected component containing the sink then the variable will have value of 0. Vice versa, if belongs to the connected component containing the sink and to the one containing the source, then the variable will have value of 1. If both nodes and belong to the same connected component, then the value of the variable will be undefined.
The way undefined variables can be handled is dependent upon the context of the problem. In the general case, given a partition of the graph in two sub-graphs and two solutions, each one optimal for one of the sub-graphs, then it is possible to combine the two solutions into one solution optimal for the whole graph in polynomial time. However, computing an optimal solution for the subset of undefined variables is still a NP-hard problem. In the context of iterative algorithms such as -expansion, a reasonable approach is to leave the value of undefined variables unchanged, since the persistence property guarantees that the target function will have non-increasing value. Different exact and approximate strategies to minimise the number of undefined variables exist.
Higher order terms
It is always possible to reduce a higher-order function to a quadratic function which is equivalent with respect to the optimisation, problem known as "higher-order clique reduction" (HOCR), and the result of such reduction can be optimized with QPBO. Generic methods for reduction of arbitrary functions rely on specific substitution rules and in the general case they require the introduction of auxiliary variables. In practice most terms can be reduced without introducing additional variables, resulting in a simpler optimization problem, and the remaining terms can be reduced exactly, with addition of auxiliary variables, or approximately, without addition of any new variable.
Notes
References
Notes
External links
Implementation of QPBO (C++), available under the GNU General Public License, by Vladimir Kolmogorov.
Implementation of HOCR (C++), available under the MIT license, by Hiroshi Ishikawa.
Combinatorial optimization
Computational problems in graph theory | Quadratic pseudo-Boolean optimization | [
"Mathematics"
] | 1,256 | [
"Computational problems in graph theory",
"Computational mathematics",
"Graph theory",
"Computational problems",
"Mathematical relations",
"Mathematical problems"
] |
59,654,909 | https://en.wikipedia.org/wiki/2%2C6-Diisopropylaniline | 2,6-Diisopropylaniline is an organic compound with the formula H2NC6H3(CHMe2)2 (Me = CH3). It is a colorless liquid although, like many anilines, samples can appear yellow or brown. 2,6-Diisopropylaniline is a bulky aromatic amine that is often used to make ligands in coordination chemistry. The Schrock carbenes often are transition metal imido complexes derived from this aniline. Condensation with diacetylpyridine and acetylacetone gives, respectively, diiminopyridine and NacNac ligands.
References
Anilines | 2,6-Diisopropylaniline | [
"Chemistry"
] | 145 | [
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
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