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62,052,484 | https://en.wikipedia.org/wiki/Stahl%27s%20theorem | In matrix analysis Stahl's theorem is a theorem proved in 2011 by Herbert Stahl concerning Laplace transforms for special matrix functions. It originated in 1975 as the Bessis-Moussa-Villani (BMV) conjecture by Daniel Bessis, Pierre Moussa, and Marcel Villani. In 2004 Elliott H. Lieb and Robert Seiringer gave two important reformulations of the BMV conjecture. In 2015, Alexandre Eremenko gave a simplified proof of Stahl's theorem.
In 2023, Otte Heinävaara proved a structure theorem for Hermitian matrices introducing tracial joint spectral measures that implies Stahl's theorem as a corollary.
Statement of the theorem
Let denote the trace of a matrix. If and are Hermitian matrices and is positive semidefinite, define , for all real . Then can be represented as the Laplace transform of a non-negative Borel measure on . In other words, for all real ,
() = ,
for some non-negative measure depending upon and .
References
Conjectures that have been proved
Theorems in analysis
Theorems in measure theory | Stahl's theorem | [
"Mathematics"
] | 237 | [
"Theorems in mathematical analysis",
"Mathematical analysis",
"Theorems in measure theory",
"Conjectures that have been proved",
"Mathematical problems",
"Mathematical theorems"
] |
62,052,741 | https://en.wikipedia.org/wiki/NGC%204320 | NGC 4320, is a peculiar galaxy located about 370 million light-years away in the constellation Virgo. It was discovered by astronomer Heinrich d'Arrest on April 15, 1865 and is a member of the NGC 4325 Group.
NGC 4320 appears to be the end result of an interaction and merger of two spiral galaxies.
See also
List of NGC objects (4001–5000)
Antennae Galaxies
Mice Galaxies
References
External links
4320
040160
Virgo (constellation)
Astronomical objects discovered in 1865
Spiral galaxies
07452
Peculiar galaxies
Interacting galaxies
NGC 4325 Group | NGC 4320 | [
"Astronomy"
] | 115 | [
"Virgo (constellation)",
"Constellations"
] |
62,053,230 | https://en.wikipedia.org/wiki/Hugh%20McIntosh%20%28civil%20engineer%29 | Hugh McIntosh (4 December 1768 - 30 August 1840) was a Scottish civil engineering contractor particularly associated with the construction of canals and docks, and also the first purpose-built passenger railway line in London.
Career
McIntosh was born in Kildrummy near Nairn in 1768, apparently attending Inverness Grammar School before working as a navvy on the Forth and Clyde Canal and later the Lancaster Canal, where he first worked as a contractor.
While working on the Lancaster Canal, McIntosh met fellow Scot John Rennie who helped nurture McIntosh's career. McIntosh followed Rennie to London to work on the city's docks, and his growing reputation as an engineer led to him being recruited by the British government in 1809 in an ultimately unsuccessful attempt to demolish fortifications at Flushing.
McIntosh then invested in land and became a developer in the Mile End district of east London. In 1812, he bid for contracts to dig the Regent's Canal and, in 1815, to work on the Surrey Commercial Docks.
With a reputation for honesty and a business with sufficient resources to complete major projects, he became the leading contractor of his day, undertaking contracts including work on the British Museum, Hampton Court, Brighton Pavilion, Buckingham Palace (working for John Nash), the Gloucester Docks and Gloucester and Sharpness Canal (working for Thomas Telford), the Aire and Calder Navigation and Goole docks, dock works at Portsmouth and Southampton, the Mythe Bridge, and the London and Greenwich Railway.
In 1837, The Gentleman's Magazine celebrated the railway project saying:
"This great national work reflects the highest honour on the gallant proprietor, Colonel Landmann, no less credit on the contractor, Mr Macintosh, under whose orders no less than 60,000,000 bricks have been laid by human hands since the Royal assent was given to the Act of Parliament for its formation in 1833."
Family life
He was married to Mary Cross. His brother James married Cross's sister.
McIntosh died of apoplexy on 30 August 1840 in Wakefield, England. The family tomb is in the grounds of St Matthias Community Centre, Poplar, London.
References
1768 births
1840 deaths
Scottish civil engineers
Civil engineering contractors | Hugh McIntosh (civil engineer) | [
"Engineering"
] | 439 | [
"Civil engineering",
"Civil engineering contractors"
] |
62,053,347 | https://en.wikipedia.org/wiki/Greta%20Panova | Greta Cvetanova Panova (, born 1983 in Sofia, Bulgaria) is a Bulgarian-American mathematician. She is a professor of mathematics and Gabilan Distinguished Professor in Science and Engineering at the University of Southern California in Los Angeles. Her research interests include combinatorics, probability and theoretical computer science.
Education and career
Panova received her B.S. in 2005 from MIT. She received M.A. in 2006 from University of California, Berkeley and Ph.D. in mathematics from Harvard University in 2011, under the supervision of Richard P. Stanley. She was then a postdoc at UCLA (2011–2014), Assistant and Associate Professor at the University of Pennsylvania (2014–2018), and is currently a tenured Professor at the University of Southern California. In 2023, she was named Gablian Distinguished Professor.
Panova research is in algebraic combinatorics with applications to geometric complexity theory, probability and statistical mechanics. , she is a co-Editor-in-Chief of the Electronic Journal of Combinatorics, and a member of the editorial board of Algebraic Combinatorics and the Arnold Mathematical Journal.
Selected awards
Panova was a three time medalist at the International Mathematical Olympiad (1999–2001, one gold and two silver medals) and a third prize winner at the William Lowell Putnam Mathematical Competition (2001). She is a recipient of Katz Fellowship (UC Berkeley), Putnam Fellowship (Harvard), James Mills Peirce Fellowship (Harvard), Simons Postdoctoral Fellowship (UCLA), and von Neumann Fellowship (IAS). Panova was an invited plenary speaker at the 2017 International Conference on Formal Power Series and Algebraic Combinatorics and at the 2023 Current Developments in Mathematics Conference. Panova is the 2020 recipient of the IMI Award, awarded once every three years by the Institute of Mathematics and Informatics at the Bulgarian Academy of Science to a Bulgarian citizen under the age of 40 for high achievements in the field of mathematics, and the 2024–5 Birman Fellow of the American Mathematics Society.
References
External links
1983 births
Living people
Scientists from Sofia
Bulgarian emigrants to the United States
Harvard University alumni
University of California, Berkeley alumni
Massachusetts Institute of Technology alumni
University of Southern California faculty
University of Pennsylvania faculty
Institute for Advanced Study visiting scholars
21st-century American mathematicians
Bulgarian women mathematicians
21st-century Bulgarian mathematicians
Combinatorialists
Probability theorists
Theoretical computer scientists
21st-century American women mathematicians | Greta Panova | [
"Mathematics"
] | 489 | [
"Combinatorialists",
"Combinatorics"
] |
62,054,384 | https://en.wikipedia.org/wiki/Carl%20Friedrich%20Irminger | Carl Friedrich Irminger (8 November 1813 in Aadorf, Switzerland27 March 1863 in Zürich) was a Swiss draughtsman, lithographer and engraver.
Life and career
Carl Friedrich Irminger is known for his watercolors and caricatures of Swiss military figures. In the 1850s he worked with painter and photographer Heinrich Schweikert (1830–1914) and created Irminger & Schweikert Photographic Institute in Zürich.
References
Further reading
Irminger, Karl Friedrich In: Hans Vollmer (Hrsg.): Allgemeines Lexikon der Bildenden Künstler von der Antike bis zur Gegenwart. Begründet von Ulrich Thieme und Felix Becker. Band 19: Ingouville–Kauffungen. E. A. Seemann, Leipzig 1926.
Johann Nepomuk Vogl (Red.): Künstlerischer Wegweiser.. In: Oesterreichisches Morgenblatt, 7. April 1847, S. 167 (Online bei ANNO)
«(Friedr. Irminger,) ein Schweizer, durch seine schönen Porträtzeichnungen auf Pergament, so wie durch Lithographien und Radierungen in der Kunstwelt bekannt, hat so eben das Porträt des auch als Schriftsteller bekannten Kunsthändlers Mor. Biermann auf Stein vollendet.»
René Perret: Frappante Ähnlichkeit. Pioniere der Schweizer Photographie. Bilder der Anfänge. BEA-und-Poly-Verl., Brugg 1991, . Frappante Ähnlichkeit. Pioniere der Schweizer Photographie. Bilder der Anfänge.
1813 births
1863 deaths
Swiss lithographers
17th-century engravers
Swiss engravers
People from Münchwilen District
Draughtsmen | Carl Friedrich Irminger | [
"Engineering"
] | 413 | [
"Design engineering",
"Draughtsmen"
] |
62,055,291 | https://en.wikipedia.org/wiki/Katalin%20Hangos | Katalin M. Hangos is a Hungarian chemical engineer whose research concerns control theory and chemical process modeling. She is a research professor in the Systems and Control Laboratory of the Institute for Computer Science and Control of the Hungarian Academy of Sciences, and a professor of electrical engineering and information systems at the University of Pannonia.
Education
Hangos earned a master's degree in chemistry at Eötvös Loránd University in 1976, and returned to Eötvös Loránd University for a bachelor's degree in computer science in 1980. She earned a Ph.D. in chemical engineering in 1984 and, through the Hungarian Academy of Sciences, a D.Sc. in process systems engineering in 1994.
Books
Hangos is the co-author of:
Process Modelling and Model Analysis (with Ian T. Cameron, Academic Press, 2001)
Analysis and Control of Nonlinear Process Systems (with József Bokor and Gábor Szederkényi, Springer, 2004)
Intelligent Control Systems: An Introduction with Examples (with Rozália Lakner and Miklós Gerzson, Kluwer, 2004)
Analysis and Control of Polynomial Dynamic Models with Biological Applications (with Gábor Szederkényi and Attila Magyar, Academic Press, 2018)
References
External links
Year of birth missing (living people)
Living people
Control theorists
Hungarian chemical engineers
Women chemical engineers
Eötvös Loránd University alumni | Katalin Hangos | [
"Chemistry",
"Engineering"
] | 283 | [
"Women chemical engineers",
"Chemical engineers",
"Control engineering",
"Control theorists"
] |
71,623,586 | https://en.wikipedia.org/wiki/Microporus%20xanthopus | Microporus xanthopus is a species of fungus in the genus Microporus. It is an inedible wood-decaying mushroom native to tropical areas.
Gallery
References
Polyporaceae
Fungus species | Microporus xanthopus | [
"Biology"
] | 44 | [
"Fungus stubs",
"Fungi",
"Fungus species"
] |
71,623,801 | https://en.wikipedia.org/wiki/List%20of%20conversion%20factors | This article gives a list of conversion factors for several physical quantities. A number of different units (some only of historical interest) are shown and expressed in terms of the corresponding SI unit.
Conversions between units in the metric system are defined by their prefixes (for example, 1 kilogram = 1000 grams, 1 milligram = 0.001 grams) and are thus not listed in this article. Exceptions are made if the unit is commonly known by another name (for example, 1 micron = 10−6 metre). Within each table, the units are listed alphabetically, and the SI units (base or derived) are highlighted.
The following quantities are considered: length, area, volume, plane angle, solid angle, mass, density, time, frequency, velocity, volumetric flow rate, acceleration, force, pressure (or mechanical stress), torque (or moment of force), energy, power (or heat flow rate), action, dynamic viscosity, kinematic viscosity, electric current, electric charge, electric dipole, electromotive force (or electric potential difference), electrical resistance, capacitance, magnetic flux, magnetic flux density, inductance, temperature, information entropy, luminous intensity, luminance, luminous flux, illuminance, radiation.
Length
Area
Volume
Plane angle
Solid angle
Mass
Notes:
See Weight for detail of mass/weight distinction and conversion.
Avoirdupois is a system of mass based on a pound of 16 ounces, while Troy weight is the system of mass where 12 troy ounces equals one troy pound.
The symbol is used to denote standard gravity in order to avoid confusion with the (upright) g symbol for gram.
Density
Time
Frequency
Speed or velocity
A velocity consists of a speed combined with a direction; the speed part of the velocity takes units of speed.
Flow (volume)
Acceleration
Force
Pressure or mechanical stress
Torque or moment of force
Energy
Power or heat flow rate
Action
Dynamic viscosity
Kinematic viscosity
Electric current
Electric charge
Electric dipole
Electromotive force, electric potential difference
Electrical resistance
Capacitance
Magnetic flux
Magnetic flux density
Inductance
Temperature
Information entropy
Modern standards (such as ISO 80000) prefer the shannon to the bit as a unit for a quantity of information entropy, whereas the (discrete) storage space of digital devices is measured in bits. Thus, uncompressed redundant data occupy more than one bit of storage per shannon of information entropy. The multiples of a bit listed above are usually used with this meaning.
Luminous intensity
The candela is the preferred nomenclature for the SI unit.
Luminance
Luminous flux
Illuminance
Radiation
Radiation – source activity
Although becquerel (Bq) and hertz (Hz) both ultimately refer to the same SI base unit (s−1), Hz is used only for periodic phenomena (i.e. repetitions at regular intervals), and Bq is only used for stochastic processes (i.e. at random intervals) associated with radioactivity.
Radiation – exposure
The roentgen is not an SI unit and the NIST strongly discourages its continued use.
Radiation – absorbed dose
Radiation – equivalent dose
Although the definitions for sievert (Sv) and gray (Gy) would seem to indicate that they measure the same quantities, this is not the case. The effect of receiving a certain dose of radiation (given as Gy) is variable and depends on many factors, thus a new unit was needed to denote the biological effectiveness of that dose on the body; this is known as the equivalent dose and is shown in Sv. The general relationship between absorbed dose and equivalent dose can be represented as
H = Q ⋅ D
where H is the equivalent dose, D is the absorbed dose, and Q is a dimensionless quality factor. Thus, for any quantity of D measured in Gy, the numerical value for H measured in Sv may be different.
Notes
External links
Soot to mm Converter
Soot to Inch Calculator
References
Conversion of units of measurement
Conversion factors | List of conversion factors | [
"Mathematics"
] | 827 | [
"Quantity",
"Conversion of units of measurement",
"Units of measurement"
] |
71,623,810 | https://en.wikipedia.org/wiki/Portuguese%20Plain%20Style%20architecture | Portuguese Plain Style architecture (Estilo Chão in Portuguese) refers to a 16th century Portuguese architectural style related to early Mannerism marked by austerity and sobriety of form. The term was coined by the American art historian George Kubler, who defines this style as "vernacular architecture, related to the traditions of a living dialect more than to the great authors of Classical Antiquity". This same author traces the origin of this style back to suggestions by Italian military architects, although there may be influences from Northern Europe and from the Portuguese architectural tradition itself.
Although often associated with the unadorned Spanish style, the truth is that this style predates the Spanish one by about a decade, corresponding to a change in taste during the reign of King John III of Portugal, in which the monarch sought "clarity, order, proportion and simplicity". Compared with the Spanish style, the human scale has not been lost in the buildings that follow this style. It was first given expression in a series of hall-churches erected in Leiria, Portalegre and Miranda do Douro in the 1550s, erected with King Johns support. It supplanted Manueline as the favoured architectural style in Portugal. Miguel de Arruda played an important role in the affirmation of this style.
It is an well proportioned architectural style that employs golden proportions, classical geometry and the golden rectangle; shapes are rectangular, compact and orthogonal. Straight lines are used to define almost everything and decoration is avoided, making buildings squat, fortified, low and clean. It is a typically Portuguese architectural expression, born from the attempt to preserve national identity, in a period of political, economic and social crisis.
Architecture
It is a very practical type of design, allowing for construction across the Portuguese empire with minor adaptations, ready to receive decoration when deemed convenient or when economic resources were available. It was very successful because it allowed transformation through the application of gilded carving, paint, tiles, etc. The same applied to exteriors. They allowed later application of decoration or simply to build a similar building, adapting the decoration to the taste of the time and place. Practical and economical, it was born from the need to develop a style of architecture that was possible to replicate from Portugal to India via Brazil, easily built and economic. To understand it in its entirety, it is essential to bear in mind its functional character and the space of the Portuguese empire. An elegant typology developed, allowing the fragile balance between the Portuguese implantation and the local decorative models. The result was ingenious, as this architecture remained in use for more than a century and as it was very practical, easily allowing adaptation through decoration, it conditioned the development of the Baroque in the territories controlled by Portugal.
Churches are basilical buildings with two bell towers, with a single nave, deep chancel, side aisles transformed into interconnected chapels with small communication doors, interior without decoration and exterior with very simple portal windows.
Gallery
See also
Portuguese colonial architecture
Architecture of Brazil
Mannerism
References
Architectural styles
Architectural history
Architecture in Portugal
Mannerism
Mannerist architecture | Portuguese Plain Style architecture | [
"Engineering"
] | 618 | [
"Architectural history",
"Architecture"
] |
71,625,153 | https://en.wikipedia.org/wiki/Oath%3A%20Chronicles%20of%20Empire%20and%20Exile | Oath: Chronicles of Empire and Exile is a 2021 board game with asymmetric gameplay and legacy elements designed by Cole Wehrle, illustrated by Kyle Ferrin, and published by Leder Games. In Oath, players compete to become the Chancellor, and the events of each game influence the events of the games that follow. Upon its release, Oath received positive reviews, and an expansion for the game is in development. The game is part of an increase in the release of games that are based on a scenario or have a campaign structure, and is focused on fantasy politics and crisis.
Gameplay
In Oath, 1-6 players compete in an asymmetric game, taking upon the role of individuals who are trying to rule a fantasy land. One Chancellor player begins with significant control over eight Sites which are divided between three regions: the Cradle, the Provinces and the Hinterland. The other players start with an Exile character that can eventually become a Citizen. Everyone has the same major actions; they may search the deck, muster troops, trade favor and secrets (the two main currencies in the game), recover relics, campaign militarily against enemies, and travel across the board. Through the use of Denizen cards that can be picked up throughout the game, players are given access to unique powers. For games with only one or two players, the game includes an automated version of the Chancellor, the Clockwork Prince.
Victory can be earned in several ways. The Chancellor, if they continue to fulfil their Oathkeeper goal throughout the game, may roll a dice three times from turn five until turn eight, increasing their chances to win each turn. Vision cards can be picked up by Exiles which also enable victory goals, and an Exile may also attempt to usurp the Chancellor by completing the game's main goal. If the Chancellor wins but a Citizen has fulfilled certain conditions, the Citizen may win instead. Often, the game will end with a losing player forced to be a kingmaker for the other players, often decided through informal deal making and metagaming.
Development
The game was in development since 2018. Wehrle sought in the production of Oath to place narrative value as a priority, and to remove any predetermined scenarios so that every element of the game could be altered. His experience of second hand board games during childhood, such as Squad Leader and other Avalon Hill board games as well as HeroQuest and Chancellorsville, led him to want to design a board game that had a "more resonant echo"; he wanted each box to have a tangible history without the player destroying parts of it, as was the norm in many legacy games. Other inspirations for Wehrle in terms of Oath included Imperium, Barbarian, Kingdom and Empire, and Blood Royale, a role-playing game.
In 2022, Wehrle announced that Leder Games was designing an expansion for Oath.
Kickstarter
A Kickstarter campaign for the game was launched in January 2020 to fund its production, with a single pledge level of $90. Backers who pledged this amount received a journal to chronicle their sessions as well as metal favor coins and resin secret tokens, which were sold separately to the public upon the game's full release. It met its funding goal of $50,000 quickly.
Reception
Oath received generally positive reviews. Dicebreaker wrote of its "small, thoughtful details" and "evocative world and deep strategy". Tabletop Gaming compared Ferrin's artwork for the game to The Dark Crystal, calling it "evocative and characterful." Polygon described the game as "an elaborate role-playing game wearing the clothes of a complex strategy title", and later praised the game for its neoprene game board. In 2021, Gamereactor complimented its production and design, but also wrote of the game's steep learning curve and niche target audience. IGN listed the game as one of the best strategy board games in 2022.
Awards
2021 Golden Geek Award for 'Most Innovative Board Game'
2021 Tabletop Gaming Award for 'Best Board Game of 2021'
2021 Dice Tower 'Best Game from a Small Publisher' nominee
2022 SXSW Gaming Awards' 'Tabletop Game of the Year' nominee
2022 American Tabletop Awards' 'Complex Games' award nominee.
See also
Root, Pax Pamir, and John Company, other board games designed by Cole Wehrle
References
External links
Oath page on the Leder Games website
American board games
Asymmetric board games
Board games introduced in 2021
Fantasy board games
Kickstarter-funded tabletop games
Legacy games | Oath: Chronicles of Empire and Exile | [
"Physics"
] | 941 | [
"Asymmetric board games",
"Symmetry",
"Asymmetry"
] |
71,625,455 | https://en.wikipedia.org/wiki/Jacques-Fran%C3%A7ois%20Le%20Poivre | Jacques-François Le Poivre (11 February 1652 – 6 December 1710) was a mathematician and geometer who was a pioneer of projective geometry. He is largely known from a single book in French on conic sections, Traité des sections du cylindrie et du cône considérées dans le solide et dans le plan, avec des démonstrations simples & nouvelles (1704).
Le Poivre was born in Mons to son of Jacques and Catherine Demeurs. The Le Poivre family had many engineers including Pierre Le Poivre (1546-1626), an architect and military engineer. Jacques-François too studied mathematics and geometry and worked as a clerk and surveyor for the city of Mons. In 1700 he moved to Paris and in 1704 he published a treatise in two parts on cylindrical and conic sections. This work largely escaped serious study and some reviewers considered it to be plagiarism of Philippe de la Hire. In any case, de la Hire's work was more well-known. In part 2, his method of central projection was essentially the same as used by de La Hire in his 1673 work Nouvelle méthode en géométrie, pour les sections des superficies coniques et cylindriques but it has been suggested that Le Poivre independently discovered this since the book included several original theorems. A second edition of the Traité was published in 1708. An earlier work on an introduction to arithmetic that Le Poivre published in 1687 has never been located. He was a friend of Guillaume de l'Hôpital and a simple proof of the intersecting chords theorem by Le Poivre impressed l'Hôpital and may have made its way into l'Hôpital's Traité analytique des sections coniques. A biography claimed that Le Poivre was a poet.
References
External links
Traité des sections du cylindrie et du cône considérées dans le solide et dans le plan, avec des démonstrations simples & nouvelles (1704) - at the German national library
Scientists from Paris
People from Mons, Belgium
1710 deaths
17th-century mathematicians from the Holy Roman Empire
1652 births
Emigrants from the Holy Roman Empire to France
Geometers
Surveyors
17th-century French mathematicians | Jacques-François Le Poivre | [
"Mathematics"
] | 460 | [
"Geometers",
"Geometry"
] |
71,626,360 | https://en.wikipedia.org/wiki/Silver%20tungstate | Silver tungstate is an inorganic tungstate with the chemical formula Ag2WO4. It has been applied in various fields such as photoluminescence, antibacterial action, ozone gas sensors and humidity sensors. It is also used in the electronic and chemical industries, and also used in proteomics research.
Phases
Silver tungstate occurs in three polymorphic phases: orthorhombic (α), hexagonal (β) and cubic (γ). α-silver tungstate is thermodynamically stable, while β- and γ-silver tungstate are metastable.
Synthesis
Silver tungstate is synthesised through the following reaction between silver nitrate and sodium tungstate, producing sodium nitrate as a byproduct:
References
Silver compounds
Tungstates | Silver tungstate | [
"Chemistry"
] | 167 | [
"Inorganic compounds",
"Inorganic compound stubs"
] |
71,627,440 | https://en.wikipedia.org/wiki/Denise%20Hinkel | Denise Hinkel is a plasma physicist at Lawrence Livermore National Laboratory.
Hinkel received her PhD in physics in 1990 from the University of California, supervised by Burton D. Fried, titled Resonant Absorption In An Inhomogeneous, Unmagnetized Plasma.
In 2007 she became a Fellow of the American Physical Society for "extensive contributions to laser-plasma interaction physics and radiation hydrodynamic design of inertial-confinement fusion targets, and to the fundamental physics of linear and nonlinear wave propagation in plasma."
She was elected to lead American Physical Society Division of Plasma Physics in 2021. Her research involves laser-plasma interactions for nuclear fusion.
Selected publications
Modeling of HF Propagation and Heating in the Ionosphere, (1992)
References
External links
Living people
American women physicists
American physicists
Plasma physicists
University of California alumni
Lawrence Livermore National Laboratory staff
Fellows of the American Physical Society
Year of birth missing (living people) | Denise Hinkel | [
"Physics"
] | 192 | [
"Plasma physicists",
"Plasma physics"
] |
71,627,900 | https://en.wikipedia.org/wiki/EUginius | EUginius is an Internet-based database application for Genetically modified organisms (GMOs). The name EUginius is an acronym and stands for EUropean GMO Initiative for a Unified Database System.
Development and commissioning
The EUginius database was created on the initiative of the German Federal Office of Consumer Protection and Food Safety (BVL) and the Dutch research Institute Wageningen Food Safety Research (WFSR, formerly RIKILT). Building on parallel preparatory work by both cooperation partners, EUginius has been jointly developed and maintained since 2010, and has been online since October 2014. The information is provided in English.
Goal
EUginius aims to assist competent authorities as well as interested private users in finding accurate information on the presence, detection and identification of GMOs. Data on the GMOs’ molecular characterisation and traits, detection methods, reference materials, and authorisation status (currently limited to the EU) are provided. EUginius is tax-financed and therefore offers its information on the GMOs freely accessible. Information on releases carried out and their geographical location are not provided in EUginius.
Types of organisms present in EUginius
Most of the GMOs present in EUginius are used for genetically modified food and feed, the majority plants (e.g. pest resistant Bt maize, Golden rice with enhanced synthesis of ß-carotene), and thus come from the field of green biotechnology. There is also information on genetically modified animals. EUginius provides for example information on a fast-growing genetically modified salmon (AquAdvantage) as well as information on genetically modified insects that have been developed to combat vectors of pathogens (e.g. Aedes aegypti OX5034, used to reduce the yellow fever mosquito population). In addition, in some cases, information is provided for the detection of genetically modified microbial production strains of food or feed additives (white biotechnology).
Since the European Union classifies organisms developed using New Breeding Techniques (NBTs) as GMOs, EUginius provides information about commercialised NBT-organisms, including genome edited organisms such as the high-oleic soybean, the larger growing pufferfish or the heat-tolerant cattle. Furthermore, EUginius lists, to some extent, published NGT organisms which present market-relevant traits.
Data in EUginius
As of August 2022, EUginius contains
901 genetically modified organisms (detailed information on GMOs)
270 PCR-detection methods (methods for detection and identification of GMOs)
451 reference materials (non-certified and certified reference materials)
Server locations and service
The database and web servers are located in Germany and are mirrored on servers in the Netherlands. Further development and troubleshooting are decided jointly by the cooperation partners.
Partnerships
Since 2018, there have also been partnerships with the Institute of Plant Breeding and Acclimatization (Instytut Hodowli i Aklimatyzacji Roślin – IHAR, based in Blonie, Poland), the Austrian Agency for Health and Food Safety (AGES, based in Vienna, Austria) and the Experimental ZooProphylactic Institute of Lazio and Tuscany (Istituto Zooprofilattico Sperimentale – IZS, based in Rome, Italy).
Beyond that, EUginius uses the element thesaurus GMO-GET1 (GMO Genetic Element Thesaurus) developed in collaboration with the Biosafety Clearing House (BCH, Montreal, Canada).
Outlook
EUginius is continuously maintained and further developed. In this way, the work of the control laboratories using EUginius is supported in a timely manner. The adaptation of the contents and their provision (e.g. information on organisms developed by NBTs and sequencing information) is carried out on an ongoing basis. The renewal of the module for accessing GMO authorisation applications is under development. Finally, an optimisation of the design to improve usability and make navigation more intuitive is planned (2023 – 2024).
References
External links
EUginius website
Federal Office of Consumer Protection and Food Safety (BVL)
Wageningen Food Safety Research (WFSR)
Biosafety Clearing House – BCH
Institute of Plant Breeding and Acclimatization IHAR
Austrian Agency for Food Security – AGES
Instituto Zooprofilattico Sperimentale – IZS
genetic engineering
Online databases | EUginius | [
"Chemistry",
"Engineering",
"Biology"
] | 910 | [
"Biological engineering",
"Genetic engineering",
"Molecular biology"
] |
71,628,096 | https://en.wikipedia.org/wiki/Potassium%20phosphide | Potassium phosphide is an inorganic semiconductor compound with the formula K3P. It appears as a white crystalline solid or powder. It reacts violently with water and is toxic via ingestion, inhalation and skin absorption. It has a hexagonal structure.
Synthesis
Potassium phosphide can be synthesised by simply reacting the two elements together:
12K + P4 -> 4K3P
Applications
Potassium phosphide is used in high power, high frequency applications and also in laser diodes.
References
Phosphides
Potassium compounds
Semiconductors | Potassium phosphide | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 117 | [
"Electrical resistance and conductance",
"Physical quantities",
"Inorganic compounds",
"Semiconductors",
"Inorganic compound stubs",
"Materials",
"Electronic engineering",
"Condensed matter physics",
"Solid state engineering",
"Matter"
] |
71,628,105 | https://en.wikipedia.org/wiki/Glossary%20of%20quantum%20computing | This glossary of quantum computing is a list of definitions of terms and concepts used in quantum computing, its sub-disciplines, and related fields.
References
Further reading
Textbooks
Academic papers
Table 1 lists switching and dephasing times for various systems.
Models of computation
Quantum cryptography
Information theory
Computational complexity theory
Classes of computers
Theoretical computer science
Open problems
Quantum computing
Wikipedia glossaries using description lists | Glossary of quantum computing | [
"Mathematics",
"Technology",
"Engineering"
] | 77 | [
"Telecommunications engineering",
"Theoretical computer science",
"Applied mathematics",
"Computer systems",
"Computer science",
"Information theory",
"Computers",
"Classes of computers"
] |
71,628,948 | https://en.wikipedia.org/wiki/ESO%20383-76 | ESO 383-76 (ESO 383-G 076) is an elongated, X-ray luminous supergiant elliptical galaxy, residing as the dominant, brightest cluster galaxy (BCG) of the Abell 3571 galaxy cluster, the sixth-brightest in the sky at X-ray wavelengths. It is located at the distance of from Earth, and is possibly a member of the large Shapley Supercluster. With a diameter of about , it is one of the largest galaxies known. It also contains a supermassive black hole, one of the most massive known with mass estimates varying from to .
Observation history
The first known observation of the galaxy was during the creation of the Morphological Catalogue of Galaxies by Boris Vorontsov-Velyaminov and V.P. Harkipova in 1974, with the catalogue entry MCG-05-33-002. The galaxy was also observed around this time by the ESO Sky Survey Atlas, a large-scale survey of the Southern Sky conducted using the 1-metre Schmidt telescope in La Silla Observatory. In 1982, the ESO/Uppsala Catalogue then lists the galaxy in its current designation form – ESO 383-G 076, indicating both its field number (field 383 out of the 606 in the survey), classification (G, for "Galaxy"), and its numerical identifier in its field. The galaxy, at this point, was nothing more than just an obscure catalogue entry.
O.G. Richter in 1984 then observed the galaxy during a redshift survey of the ESO/SRC Survey Fields 444 and 445 of the Klemola 27 group (now known as the IC 4329 galaxy group). The group consists of prominent galaxies such as the namesake IC 4329 – another massive supergiant elliptical that is also an extreme Seyfert galaxy, and NGC 5291 – a disturbed interacting galaxy pair. ESO 383-76, initially thought to be a member of this group, was listed as the 442nd galaxy in Richter's table entry and has been given the morphology E/S0 (either an elliptical or lenticular galaxy). The galaxy has also been included in the Southern Galaxy Catalogue, containing nearly 5,000 galaxies, compiled in 1985 by the husband-and-wife astrophysicists Gérard and Antoinette de Vaucouleurs, along with H.G. Corwin Jr.
ESO 383-76 would be additionally recorded in many subsequent galaxy surveys, such as the survey of the Hydra–Centaurus Supercluster by L.N. da Costa et al in 1986, and moreover a photometric catalogue by Lauberts and Valentijn in 1989 that made the first angular diameter measurements of the galaxy. This includes the D25 and D25.5 B-band isophotes, as well as the 50% total light emission (the half-light radius) and variations of it (60%, 70%, and 90%). A.P. Fairall et al would further incorporate the galaxy in their wide-scale survey of the Hydra-Centaurus Supercluster in 1989. It was additionally included in many other surveys due to its location in the sky in the rich Centaurus region and the wide-scale research of extragalactic objects near the Milky Way plane by the last decade of the 20th century. The galaxy has additionally been catalogued by Alan Dressler in 1991 during an analysis of velocities of 1,314 galaxies near the Milky Way galactic plane region – allowing to pinpoint the location and verify the existence of the Great Attractor.
Description
ESO 383-76 is a supergiant elliptical galaxy (type-cD galaxy) of an advanced Hubble morphology (E5, with E0 being spherical and E7 being flattened), with its major axis being more than twice the length of its minor axis. The galaxy is a very luminous source of X-rays, and is the sixth-brightest X-ray source in the sky.
In an analysis of the cluster A3571 by H. Quintana and R. de Souza in 1994, ESO 383-76 has been noted to have a very elongated shape with a diffuse halo extending throughout the cluster, suggesting that the galaxy had formed very early during the formation of Abell 3571 and it retains the original imprint of its collapsing cloud. The mass of the core region, which also includes the galaxy, is on the order of .
Size
There are various methods used in astronomy in defining the size of a galaxy, and each of them can yield different results with respect to the other. This is usually affected by exposure time, the wavelength used, and the instrument being used.
One method that is commonly used in the astronomical literature is the galaxy effective radius where 50% of the total galaxy's light was emitted; variations of 60%, 70%, and 90% are also used. An estimation of the galaxy's size by the ESO/Uppsala catalogue's broad-band photographic plates in 1989 using the 90% total light definition yield a very large apparent diameter of 555.9 arcseconds (about 9.25 arcminutes; 27% the width of the full moon in the sky), which using the currently accepted distance to the galaxy yield a diameter of . This makes it one of the largest physical diameter measurements of any galaxy known – 20 times that of the Milky Way's diameter, and 3.5 times that of the maximum estimated diameter of IC 1101.
Alternative measurements from the same study using other methods (such as the D isophote) yield diameters as small as , with various estimates in between depending on the measurement. In a study in 1994, the halo of the galaxy (defined as the brightness at 2σ above background) has a diameter of about . The paper states that this is on the scale of the distance between the Milky Way and Andromeda galaxies. The halo extends throughout a large part of Abell 3571.
Environment
ESO 383-76 lies at the center of the Abell 3571 galaxy cluster, which is a possible member of the Shapley Supercluster (or alternatively the Shapley 8 Concentration – an outlying structure). This massive supercluster hosts many clusters with similar supergiant elliptical galaxies, among them ESO 444-46.
See also
Messier 87
ESO 306-17
NeVe 1
Notes
References
Elliptical galaxies
Centaurus
Galaxies discovered in 1974
-05-33-002
048896
Shapley Supercluster | ESO 383-76 | [
"Astronomy"
] | 1,360 | [
"Centaurus",
"Constellations"
] |
71,629,400 | https://en.wikipedia.org/wiki/Manganese%28III%29%20chloride | Manganese(III) chloride is the hypothetical inorganic compound with the formula MnCl3.
The existence of this binary halide has not been demonstrated. Nonetheless, many derivatives of MnCl3 are known, such as MnCl3(THF)3 and the bench-stable MnCl3(OPPh3)2. Contrasting with the elusive nature of MnCl3, trichlorides of the adjacent metals on the periodic table—iron(III) chloride, chromium(III) chloride, and technetium(III) chloride—are all isolable compounds.
History of MnCl3 and its adducts
MnCl3 was claimed to be a dark solid and produced by the reaction of "anhydrous manganese(III) acetate" and liquid hydrogen chloride at −100 °C and decomposes above -40 °C. Other claims involved reaction of manganese(III) oxide, manganese(III) oxide-hydroxide, and basic manganese acetate with hydrochloric acid. Given recent investigations however, such claims have been disproved or called into serious doubt. Specifically, all known compounds containing MnCl3 are known to be solvent or ligand-stabilized adducts.
Adducts
MnCl3 can be stabilized by complexation to diverse Lewis bases, as has been established over the course of many years of study. Meta stable acetonitrile-solvated Mn(III)Cl3 can be prepared at room temperature by treating [Mn12O12(OAc)16(H2O)4] with trimethylsilyl chloride. The treatment of permanganate salts with trimethylsilylchloride generates solutions containing Mn(III)–Cl species for alkene dichlorination reactions; electrocatalytic methods that use Mn(III)–Cl intermediates have been developed for the same purpose.
The reaction of manganese dioxide with hydrochloric acid in tetrahydrofuran gives MnCl3(H2O)(THF)2. Manganese(III) fluoride suspended in THF reacts with boron trichloride, giving MnCl3(THF)3 which has the appearance of dark purple prisms. This compound has a monoclinic crystal structure, reacts with water, and decomposes at room temperature.
The most readily handled of this series of adducts is MnCl3(OPPh3)2.
Pentachloromanganate(III)
Another common manganese(III) chloride compound is the pentachloromanganate(III) dianion. It is usually charge balanced with counterion(s) like tetraethylammonium. The pentachloromanganates are typically green in color, light sensitive, maintain pentacoordination in solution, and have S = 2 ground states at room temperature. Crystal structures of pentachloromanganate indicate the anion is square pyramidal. Tetraethylammonium pentachloromanganate(III), [Et4N]2[MnCl5], can be prepared and isolated by treating suspension of [Mn12O12(OAc)16(H2O)4] in diethyl ether with trimethylsilylchloride, collecting the resulting purple solid in the dark, and then treating this solid with 0.6 M solution of tetraethylammonium chloride. The green product is air stable but should be kept in the dark.
Manganese(III) monochloride compounds
Some manganese compounds with macrocyclic tetradentate coordination can stabilize the manganese(III) monochloride, Mn(III)–Cl, moiety. Jacobson's catalyst is an example of a coordination compound containing the Mn(III)–Cl moiety and is stabilized by N,N,O,O coordination from a salen ligand. Jacobson's catalyst and related Mn(III)–Cl complexes react with O-atom transfer reagents to form high-valent Mn(V)O that are reactive in alkene epoxidation. Tetraphenylporphyrin Mn(III)Cl is a related commercially available compound.
Other manganese(III) chloride complexes
Bis(triphenylphosphineoxide) manganese(III) chloride
References
Manganese(III) compounds
Chlorides | Manganese(III) chloride | [
"Chemistry"
] | 917 | [
"Chlorides",
"Inorganic compounds",
"Salts"
] |
71,631,370 | https://en.wikipedia.org/wiki/Russula%20vinosa | Russula vinosa, commonly known as the darkening brittlegill, is a species of basidiomycete mushroom found in coniferous woodlands in Europe and North America in summer and early autumn. Unlike many red-capped members of the russula genus, it is edible and mild-tasting. It is usually understood to have a symbiotic relationship with evergreen tree roots, except for in mountainous areas where it has occasionally associated with birches.
Taxonomy
Russula vinosa was originally described in the Swedish guide Svampbok, (), written by for publication in 1901. Romel who came up with the synonymous Russula obscura was an editor for the 1913 release of the text. The specific epithet "vinosa" is derived from the Latin vinum "wine", likely alluding to the wine-colored cap of this species that is capable of acting as a dye.
Description
The cap is concave and wine to red-brown in colour, often fading to a pale white or tan in the center with age. The widely spaced gills are white, and adnexed or free. The stipe is cylindrical and white or cream colored. The brittle flesh is light and the taste is mild.
Similar species
The red-capped color of Russula vinosa is almost impossible to visually separate from other toxic and inedible red-capped Russulas, such as the bloody brittlegill (R. sanguinaria), the sickener (R. emetica), and the beechwood sickener (R. nobilis). It may also be confused with similar edible species such as Russula paludosa and Russula decolorans. It is therefore important to identify the mushroom with absolute certainty before consumption. Chinese and Southeast Asian populations of R. vinosa have been determined to be genetically distinct enough from R. vinosa to be placed in a separate, but anatomically identical species, R. griseocarnosa.
Distribution and habitat
Russula vinosa is found in Europe and North America. It is known from Great Britain, Southern Europe, New England, and Fennoscandia. It usually occurs in coniferous tree stands in summer and early autumn.
Edibility
Unlike many other red-capped members of the genus, Russula vinosa is mild-tasting and edible. In Sweden where its edibility is noted, it is known as "Vinkremla" alluding to its wine color.
See also
List of Russula species
References
vinosa
Fungi described in 1901
Fungi of Europe
Fungi of North America
Edible fungi
Fungus species | Russula vinosa | [
"Biology"
] | 521 | [
"Fungi",
"Fungus species"
] |
71,632,647 | https://en.wikipedia.org/wiki/Solorinic%20acid | Solorinic acid is an anthraquinone pigment found in the leafy lichen Solorina crocea. It is responsible for the strong orange colour of the medulla and the underside of the thallus in that species. In its purified crystalline form, it exists as orange-red crystals with a melting point of .
The structure of solorinic acid, 2-n-hexanoyl-1,3,8-trihydroxy-6-methoxy-anthraquinone, was proposed by Koller and Russ in 1937, and verified by chemical synthesis in 1966.
Norsolorinic acid, (C20H18O7, 2-hexanoyl-1,3,6,8-tetrahydroxyanthraquinone), is a closely related compound also found in Solorina crocea.
Solorinic acid was used as the internal standard in the establishment of a standardized method for the identification of lichen products using high-performance liquid chromatography. This is because it is quite a hydrophobic compound, and consequently will elute more slowly than most lichen products, making possible the identification of lichen extracts containing chlorinated xanthones or long chain depsides.
Although usually associated with Solorina crocea, solorinic acid was reported as a lichen product from the crustose, rock-dwelling lichen Placolecis kunmingensis, described as a species new to science in 2019.
References
Lichen products
Polyketides
Anthraquinones | Solorinic acid | [
"Chemistry"
] | 322 | [
"Biomolecules by chemical classification",
"Polyketides",
"Natural products",
"Lichen products"
] |
71,632,997 | https://en.wikipedia.org/wiki/Urban%20Forestry%20and%20Urban%20Greening | Urban Forestry and Urban Greening is a peer-reviewed scientific journal published by Urban & Fischer, an imprint of Elsevier. The editor-in-chief is Wendy Chen. Coverage includes research regarding urban and peri-urban forests and other nearby vegetation.
Abstracting and indexing
This journal is indexed and abstracted in:
Science Citation Index Expanded
Social Sciences Citation Index
Biological Abstracts
BIOSIS Previews
Current Contents/Agriculture, Biology & Environmental Sciences
Current Contents/Social and Behavioral Science
GEOBASE
Scopus
See also
Urban area
References
External links
Elsevier academic journals
Academic journals established in 2002
English-language journals
Forestry journals | Urban Forestry and Urban Greening | [
"Environmental_science"
] | 123 | [
"Environmental science journals",
"Forestry journals"
] |
71,634,579 | https://en.wikipedia.org/wiki/GW-788%2C388 | GW 788388 is a synthetic compound which acts as a potent and selective inhibitor for TGF beta receptor 1. It has applications in research into various disorders such as liver, kidney and heart disease (especially associated with Chagas disease), and potential antiviral properties.
See also
Galunisertib
LY-2109761
References
Kinase inhibitors
Pyrazoles
Pyridines | GW-788,388 | [
"Chemistry"
] | 85 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
71,636,543 | https://en.wikipedia.org/wiki/Tricholoma%20robustum | Tricholoma robustum is an edible mycorrhizal mushroom in the family Tricholomataceae. In Japan it is called matsutake-modoki (pseudo-matsutake), and colloquially referred to as obasan no matsutake ("old lady's matsutake"), because it resembles matsutake mushroom while being smaller and less aromatic and tasty.
Description
Resembles matsutake, but the fruiting bodies are much smaller in size. The cap is 4–10 cm, convex or flat of uneven reddish-brown color, with small, often upright scales. The gills are white, then dirty pink, red speckled. The stipe reaches 6–8 cm in length and 1.5-2.5 cm in thickness, with a narrow ring, white at the top, the color of a hat under the ring. The flesh is dense, white at first, slightly pink when cut, then red, stains brown and blackens when cooked. It has a strong smell of fresh flour. Spores ellipsoidal 6-7 x 3.5-4 μm, smooth.
Distribution and habitat
It is distributed throughout the northern hemisphere (including Polesia and forest steppes of Ukraine), especially in the northern temperate zone. It is an ectomycorrhizal fungus found in coniferous forests, forming relationship with pine trees (especially Pinus densiflora), on sandy soils. It often grows in the same forests as matsutake, although it fruits later (August–October).
Edibility
Edible mushroom. In Ukraine it is considered tasty and used fresh. In Japan it is considered to be mediocre in taste and smell, inferior to real matsutake.
References
Зерова М. Я., Єлін Ю. Я., Коз'яков С. М. Гриби: їстівні, умовно їстівні, неїстівні, отруйні. — Кyiv: Урожай, 1979. — p 134–135.
robustum
Edible fungi
Fungi of Europe
Fungi of Japan
Fungus species | Tricholoma robustum | [
"Biology"
] | 468 | [
"Fungi",
"Fungus species"
] |
71,638,083 | https://en.wikipedia.org/wiki/Project%20Nimbus | Project Nimbus () is a cloud computing project of the Israeli government and its military.
Overview
The Israeli Finance Ministry announced in April 2021 that the contract is to provide "the government, the defense establishment, and others with an all-encompassing cloud solution." Through a $1.2 billion contract, technology companies Google (Google Cloud Platform) and Amazon (Amazon Web Services) were selected to provide Israeli government agencies with cloud computing services, including artificial intelligence and machine learning. Under the contract, the companies will establish local cloud sites that will "keep information within Israel's borders under strict security guidelines." According to a Google spokesperson, the contract is for workloads related to "finance, healthcare, transportation, and education" and does not deal with highly sensitive or classified information," through the tech companies are contractually forbidden from denying service to any particular entities of the Israeli government.
Although Project Nimbus' specific mission has not yet been revealed, Google Cloud Platform's AI tools could give the Israeli military and security services the capability for facial detection, automated image categorization, object tracking & sentiment analysis – tools that have previously been used by U.S. Customs and Border Protection for border surveillance.
Project Nimbus has four planned phases: the first is purchasing and constructing the cloud infrastructure, the second is crafting government policy for moving operations onto the cloud, the third is moving operations to the cloud, and the fourth is implementing and optimizing cloud operations.
The terms Israel set for the project contractually forbid Amazon and Google from halting services due to boycott pressure. A Google spokesperson said that all Google Cloud customers must abide by its terms of service which prohibit customers from using its services to violate people's legal rights or engage in violence, but internal documents from both Google and the Israeli government contradict this claim.
Israeli–Palestinian conflict
Circa 2022, the contract drew rebuke and condemnation from the companies' shareholders as well as their employees, over concerns that the project would lead to further abuses of Palestinians' human rights in the context of the ongoing occupation and the Israeli–Palestinian conflict. Specifically, they voice concern over how the technology will enable further surveillance of Palestinians and unlawful data collection on them as well as facilitate the expansion of Israel's illegal settlements on Palestinian land.
Ariel Koren, who had worked as a marketing manager for Google's educational products and was an outspoken opponent of the project, was given the ultimatum of moving to São Paulo within 17 days or losing her job. In a letter announcing her resignation to her colleagues, Koren wrote that Google "systematically silences Palestinian, Jewish, Arab and Muslim voices concerned about Google's complicity in violations of Palestinian human rights—to the point of formally retaliating against workers and creating an environment of fear," reflecting her view that the ultimatum came in retaliation for her opposition to and organization against the project. She filed retaliation complaints with Google's human resources department and the National Labor Relations Board (NLRB), which dismissed her case based on lack of evidence. The NLRB also found that the ultimatum predated Koren's protected activities.
In 2022, Jewish Voice for Peace and MPower Change launched a campaign called No Tech For Apartheid – also known as #NoTechForApartheid – opposing the project. More than 200 Google workers joined a protest group named after this campaign, who argue that the relative lack of oversight for the project mean it will likely be used for violent purposes.
In March 2024, a Google Cloud software engineer was fired after a video of them shouting "I refuse to build technology that empowers genocide," in reference to Project Nimbus, at a company event went viral. In April, dozens of employees participated in sit-ins at Google's New York & Sunnyvale Headquarters to protest against Google supplying cloud computing software to the Israeli government. Employees occupied the office of Google Cloud chief executive Thomas Kurian. Nine employees were charged with trespassing and 28 were fired.
In April, former Google employees fired for protesting with #NoTechForApartheid, citing an article in +972 Magazine, expressed concerns over Israel's current use of AI-assisted targeting in the Gaza Strip: a program named “The Gospel” categorizes buildings as military bases, while programs called “Lavender” and “Where’s Daddy” identify and falsely classify Palestinian civilians as 'terrorists' and track the their movements for target selection.
In December 2024, a New York Times article reported that Google lawyers were worried that "Google Cloud services could be used for, or linked to, the facilitation of human rights violations, including Israeli activity in the West Bank." at least as early as four months before the Nimbus contract was signed.
References
2021 establishments in Israel
Amazon Web Services
Criticism of Google
Google Cloud
Government of Israel
Human rights in the State of Palestine
Israel Defense Forces
Military projects
Surveillance databases
Projects established in 2021 | Project Nimbus | [
"Engineering"
] | 1,010 | [
"Military projects"
] |
71,638,437 | https://en.wikipedia.org/wiki/LTT%209779 | LTT 9779 (or Uúba) is a G-type main-sequence star located away from the Solar System in the constellation of Sculptor. The star is about 95% the radius and about the same mass as the Sun, but younger than the Sun at 1.7 billion years old, hence its lower luminosity (about ). It has a temperature of and a rotation period of 45 days. LTT 9779 is orbited by one known exoplanet.
Nomenclature
The designation LTT 9779 comes from one of Luyten's catalogues of stars with high proper motion.
In August 2022, this planetary system was included among 20 systems to be named by the third NameExoWorlds project. The approved names, proposed by a team from Colombia, were announced in June 2023. LTT 9779 is named Uúba and its planet is named Cuancoá, after the U'wa language word referring to "stars", "seeds", or "eyes" and the name for the morning star, respectively.
Planetary system
The discovery of the exoplanet LTT 9779 b using TESS was published in 2020. It is an ultra-hot Neptune with about 29 times the mass and 4.7 times the radius of Earth and an orbital period of less than a day. These parameters make it one of the very few known planets in the Neptunian desert. Observations using the Spitzer Space Telescope have measured the planet's dayside temperature at , and observations by CHEOPS have shown the planet to be highly reflective, with an albedo of 80%.
A study published in 2019, prior to the confirmation of LTT 9779 b, proposed a second candidate planet in the system based on transit timing variations, but this has not been confirmed, and the study that confirmed LTT 9779 b found no evidence of transit timing variations.
References
Sculptor (constellation)
G-type main-sequence stars
Planetary systems with one confirmed planet
CD-38 15670
117883
0193
Uúba | LTT 9779 | [
"Astronomy"
] | 427 | [
"Constellations",
"Sculptor (constellation)"
] |
71,638,617 | https://en.wikipedia.org/wiki/Machilus%20kurzii | Machilus kurzii is a species of flowering plant in the laurel family (Lauraceae). It is native to mainland tropical Asia.
Description
Machilus kurzii is a small to medium-sized tree, growing 8 to 15 meters tall.
Range and habitat
Machilus kurzii ranges from the Eastern Himalayas in the west through northern Indochina and southern China (Yunnan province).
It is native to montane evergreen broadleaf forests and secondary growth, sometimes over limestone, between 800 and 2,000 meters elevation.
Human use
In Laos, the bark of Machilus kurzii, known as bong tree or yangbong, is harvested for gum and aromatic oils which are used to make incense sticks. Bong tree bark from wild trees has been over-harvested from wild trees, and wild tree populations have declined significantly. Since the early 2000s Laotians have been establishing hillside commercial bong tree plantations.
References
kurzii
Flora of East Himalaya
Flora of Indo-China
Flora of Yunnan
Incense material | Machilus kurzii | [
"Physics"
] | 209 | [
"Incense material",
"Materials",
"Matter"
] |
71,638,720 | https://en.wikipedia.org/wiki/L%20168-9 | L 168-9 (also known as GJ 4332 or TOI-134, officially named Danfeng) is a red dwarf star located away from the Solar System in the constellation of Tucana. The star has about 61% the mass and 60% the radius of the Sun. It has a temperature of and a rotation period of 29 days. L 168-9 is orbited by one known exoplanet.
Nomenclature
The designation L 168-9 comes from Luyten's first catalogue of stars with high proper motion.
In August 2022, this planetary system was included among 20 systems to be named by the third NameExoWorlds project. The approved names, proposed by a team from China, were announced in June 2023. L 168-9 is named Danfeng and its planet is named Qingluan, after mythological birds of ancient China.
Planetary system
The exoplanet L 168-9 b, officially named Qingluan, was discovered in 2020 using TESS. At the discovery, this terrestrial super-Earth was thought to have about 4.6 times the mass and 1.39 times the radius of Earth, and an estimated equilibrium temperature of . L 168-9 b is a target for observation and atmospheric characterization with the James Webb Space Telescope, and has been observed as one of its first targets.
A newer study refined the planetary parameters of L 168-9 b. The newer research found a lower mass of and a higher radius of . These parameters imply a lower density of , in contrast to the previous value of . Given the lower density of the planet, it more likely has a pure rock composition, rather than a 50% iron core and 50% silicate mantle as previously proposed. The orbital parameters show little variation, while the equilibrium temperature was updated to .
Transmission spectra of combined near- and mid-infrared observations by the James Webb Space Telescope showed no atmospheric features. However, further observations are required to rule out a thick (100 bar) carbon dioxide atmosphere, which could also explain the data.
References
Tucana
M-type main-sequence stars
Planetary systems with one confirmed planet
CD-60 08051
4332
115211
0134
Danfeng | L 168-9 | [
"Astronomy"
] | 447 | [
"Tucana",
"Constellations"
] |
71,639,068 | https://en.wikipedia.org/wiki/Hydrostatic%20bubbles | Hydrostatic bubbles, also known as philosophical bubbles, gravity beads, aerometrical beads and hydrometer beads, are a type of hydrometer invented in 1757 by Alexander Wilson of Glasgow. The design was subsequently improved and patented by the glassblower and instrument maker Isabella Lovi of Edinburgh in 1805. The instrument, which consists of a set of glass beads, seems to have been particular to Scotland and was only used (for example, in determining the density of spirits) until the early 19th century, when it was largely superseded by more accurate methods.
Operating principle
In Lovi's version of the instrument, a set of hollow glass beads was created, each differing in density from the next by 0.002 units. When added to a liquid of unknown density, the beads that were more dense than the liquid sank, and those that were less dense than the liquid floated. The density of the liquid was indicated as falling between the density of the least dense bead that sank, and the most dense bead that floated.
The operating principle is similar to that of the Galilean thermometer.
References
Laboratory equipment
Laboratory glassware
Density meters
Scottish inventions
18th-century inventions | Hydrostatic bubbles | [
"Physics",
"Technology",
"Engineering"
] | 238 | [
"Density",
"Density meters",
"Physical quantities",
"Measuring instruments"
] |
71,639,151 | https://en.wikipedia.org/wiki/Monostrontium%20ruthenate | Monostrontium ruthenate is the inorganic compound with the formula SrRuO3. It is one of two main strontium ruthenates, the other having the formula Sr2RuO4. SrRuO3 is a ferromagnetic. It has a perovskite structure as do many complex metal oxides with the ABO3 formula. The Ru4+ ions occupy the octahedral sites and the larger Sr2+ ions are distorted 12-coordinate.
References
Strontium compounds
Ruthenates
Transition metal oxides
Ferromagnetic materials
Perovskites | Monostrontium ruthenate | [
"Physics"
] | 126 | [
"Materials",
"Ferromagnetic materials",
"Matter"
] |
71,640,094 | https://en.wikipedia.org/wiki/Time%20in%20Burkina%20Faso | Time in Burkina Faso is given by a single time zone, denoted as Greenwich Mean Time (GMT; UTC+00:00). Burkina Faso shares this time zone with several other countries, including fourteen in western Africa. Burkina Faso does not observe daylight saving time (DST).
IANA time zone database
In the IANA time zone database, Burkina Faso is given one zone in the file zone.tab—Africa/Ouagadougou. "BF" refers to the country's ISO 3166-1 alpha-2 country code. Data for Burkina Faso directly from zone.tab of the IANA time zone database; columns marked with * are the columns from zone.tab itself:
See also
Time in Africa
List of time zones by country
References
External links
Current time in Burkina Faso at Time.is
Time in Burkina Faso at TimeAndDate.com
Time by country
Geography of Burkina Faso
Time in Africa | Time in Burkina Faso | [
"Physics"
] | 187 | [
"Spacetime",
"Physical quantities",
"Time",
"Time by country"
] |
71,641,447 | https://en.wikipedia.org/wiki/Chirality%20timeline | Chirality timeline presents a timeline of landmark events that unfold the developments happened in the field of chirality.
Many molecules come in two forms that are mirror images of each other, just like our hands. This type of molecule is called chiral. In nature, one of these forms is usually more common than the other. In our cells, one of these mirror images of a molecule fits "like a glove," while the other may be harmful.
In nature, molecules with chirality include hormones, DNA, antibodies, and enzymes. For example, (R)-limonene smells like oranges, while (S)-limonene smells like lemons. Both molecules have the same chemical formula, but their spatial orientations are different, which makes a big difference in their biological properties. Chiral molecules in the receptors in our noses can tell the difference between these things. Chirality affects biochemical reactions, and the way a drug works depends on what kind of enantiomer it is. Many drugs are chiral and it is important that the shape of the drug matches the shape of the cell receptor it is meant to affect. Mismatching will make the drug less effective, which could be a matter of life and death, as happened with thalidomide in the 1960s.
It has long been known that structural factors, particularly chirality and stereochemistry, have a big impact on pharmacological efficacy and pharmacokinetic behavior. Since more than a century ago, pertinent information pertaining to chirality has been accumulating in numerous fields, in particular, physics, chemistry and biology, at an accelerated rate, giving rise to more comprehensive and in-depth reasoning, conceptions, and ideas. This page offers a chronology of significant contributions that have been made in the journey of chirality [1809 to 2021].
Chirality timeline
See also
Chirality
Chiral drugs
Stereochemistry
Timeline of chemistry
List of Nobel Laureates in chemistry
References
External links
Official website of the Nobel Foundation
Chirality
Stereochemistry | Chirality timeline | [
"Physics",
"Chemistry",
"Biology"
] | 426 | [
"Pharmacology",
"Origin of life",
"Biochemistry",
"Stereochemistry",
"Chirality",
"Space",
"nan",
"Asymmetry",
"Biological hypotheses",
"Spacetime",
"Symmetry"
] |
49,273,219 | https://en.wikipedia.org/wiki/Boletopsis%20smithii | Boletopsis smithii is a species of hydnoid fungus in the family Bankeraceae. It was described as new to science in 1975 by mycologist Keith A. Harrison, from collections made in Washington.
References
External links
Fungi described in 1975
Fungi of the United States
Thelephorales
Fungi without expected TNC conservation status
Fungus species | Boletopsis smithii | [
"Biology"
] | 72 | [
"Fungi",
"Fungus species"
] |
49,273,286 | https://en.wikipedia.org/wiki/Producing%20Great%20Sound%20for%20Film%20and%20Video | Producing Great Sound for Film and Video: Expert Tips from Preproduction to Final Mix is a non-fiction, filmmaking handbook. It covers the process of acquiring quality sound for motion picture productions.
Author Jay Rose is an Emmy-award winning sound professional. He has won over 150 major awards including 12 Clios, and he has contributed to nearly 15,000 commercials. His work includes the MGM release Two Weeks.
The book is published by Focal Press, a media and technology publishing company. Focal Press is an imprint of the academic press Taylor & Francis.
The book was first published in 1999 under the title Producing Great Sound for Digital Video by Miller Freeman Books and was 375 pages. Seventeen years later, as of 2016, the book is in its fourth edition, and stands at 520 pages.
It has been a part of required reading at many film schools, including the University of Southern California (USC).
The book was also awarded five out of five stars by Videomaker Magazine.
When released, Millimeter Magazine noted that the book was one of very few publications extensively covering the art of capturing motion picture sound.
Producing Great Sound for Film and Video has been called, "...the book on the subject."
Overview
Producing Great Sound for Film and Video is broken into four main sections, ordered to reflect real-world filming situations:
Audio Basics
Planning and Pre-Production
Production Sound
Postproduction
Subjects covered include analog versus digital audio, recording and using sound effects, microphone techniques, ADR, mixing, and mastering.
One section highlighted as unique by Videomaker Magazine was that on "editing voices." Rose breaks down how human speech works, and how that translates to film and video productions. Tips include stealing unvoiced sounds from other characters, or people speaking in a scene, and using them to replace problematic recordings of others. The "editing voices" section also discusses sounds with "hard attacks" and training the ear to hear phonemes, which helps in isolating and correcting speech recording issues.
Numerous "recipes" for dealing with common sound issues, such as reducing or eliminating echo on sets, and removing line hum and buzz from recorded audio, are also provided.
Eliva Silva writing for San Antonio Express-News said of the book:
[It is] the whole theory -- and beautiful theory -- on the science of audio and the way that audio is recorded through voltage, converted into digital information, back to voltage into sound.
Style
Author Rose states in the book that he wishes to appeal to technical and non-technical people alike, adding he hopes to keep the book approachable and conversational in tone, dispelling the idea that audio needs to be difficult to understand. He states that audio is not "rocket science." While the book does contain math and science, Rose points out the math is at an elementary school level and the physics is "common sense."
The current version of the book provides downloadable files including sample sounds and music, diagnostic tools and additional tutorials allowing the reader to practice with the principles explained. Earlier versions of the book included a CD-ROM of similar assets.
In 2003, Millimeter Magazine wrote about the book:
Digital artists are very much hands-on, and Rose is the right man to write audio books for this new generation of filmmakers. Rose operates his own boutique sound studio and bridges the analog and digital eras - he's made the discoveries and mistakes that no one should have to learn on the job. This direct experience with DV equipment and projects is apparent throughout the book.
Classroom use
Major universities and film schools that have used the book as a textbook include:
University of Southern California (USC)
UCLA Extension
Long Island University
Wichita State University
Fredonia State University of New York
California State University, Northridge
A 33-page instructor guide is also provided by the publisher.
Reception
Critical reviews
Covering the first edition of the book, Videomaker Magazine noted the high price tag of the book, but said:
With PBS and Turner Network Television production experience under his belt, author Jay Rose brings a wealth of experience to Producing Great Sound for Digital Video...the book is replete with facts and useful information.
Of the second edition, Millimeter Magazine said:
Shortchanging film sound is typical of new filmmakers, and the emphasis on picture over sound is a bias running through film schools and film publications - articles, books, and courses on visual subjects far outnumber those on film sound. Author Jay Rose is single-handedly addressing the problem.
John Hartney writing for Creative COW said of the second edition,
...it offers such a wide range of usable information about hands-on digital audio production, that by reading it, the reader is empowered with production skills and enlightened by an appreciation of how the experience of audio enriches video.
In 2008, covering the third edition of the book, Videomaker Magazine awarded it "five out of five stars" and said:
I have been looking for this book for 20 years - no exaggeration...The chapter on Editing Voices alone is worth the price tag.
Entertainment industry reviews
Academy Award winner Randy Thom (director of Sound Design at Skywalker Sound, Oscar winner for The Right Stuff and The Incredibles) wrote praise of the author and book:
Jay Rose is one of the leaders in spreading the gospel of using sound creatively. He presents cutting-edge ideas about the collaboration of sound and image, and also covers the basics… all in an easy to read, easy to understand style.
Academy Award nominated sound mixer Jeff Wexler (Independence Day, The Last Samurai, Fight Club) wrote a blurb for the book stating:
"This is the definitive book. It should be mandatory reading for anyone who is seriously considering a career making movies."
References
Books about film
Handbooks and manuals
Audio engineering
Sound recording
Sound technology
Sound production
Broadcast engineering
Media studies textbooks | Producing Great Sound for Film and Video | [
"Engineering"
] | 1,191 | [
"Electrical engineering",
"Broadcast engineering",
"Electronic engineering",
"Audio engineering"
] |
49,273,370 | https://en.wikipedia.org/wiki/Hyperloop%20pod%20competition | The Hyperloop Pod Competition was an annual competition sponsored by SpaceX from 2015 to 2019 in which a number of student and non-student teams participated to design—and for some teams, build—a subscale prototype transport vehicle in order to demonstrate technical feasibility of various aspects of the Hyperloop concept. The competitions were open to participants globally, although all competitions and judging occurred in the United States of America.
A competition in 2020 on a longer track was envisioned; however, in the event, no longer track was built and the pod-racing competition was superseded in 2021 by a tunnel-boring competition, with the aim for teams to rapidly and accurately build a tunnel -long and -wide.
Overview
There were three judging phases in the 2015–2017 competition: a design competition that was held in January 2016, and two on-track competitions—27–29 January 2017, and, Competition Weekend II, 25–27 August 2017. The on-track portion of the competition is run on the SpaceX Hyperloop test track—or Hypertube—a mile-long, partial-vacuum, diameter steel tube purpose-built in Hawthorne, California, for the competition.
Thirty of the 115 teams that submitted designs in January 2016 were selected to build hardware to compete on a sponsored Hyperloop test track in January 2017. There were more than 1,000 applicants at earlier stages of the competition. The first competition completed in January 2017, with 27 teams from around the world participating. Delft Hyperloop from the Technical University of Delft won the first overall prize. WARR Hyperloop, from the Technical University of Munich, won top honors. In April 2017, 24 teams were selected to compete in Competition Weekend II held in August; WARR Hyperloop won top honors with a top speed in the mile-long test track.
In July 2018, 18 teams competed in the main competition with top speed as the only judged criterion; two additional teams competed in the levitation sub-competition. WARR Hyperloop again won top honors in the main competition, beating its own record with a run; UCSB Hyperloop was the only team to be able to compete in the levitation sub-competition, thus automatically winning.
It was announced during Competition III that Competition IV was confirmed to take place in the northern hemisphere summer of 2019. Technical University of Munich won the competition, and the 2020 Hyperloop competition was announced.
Results
History
The outline of the original Hyperloop concept was made public in August 2013 by the release of a preliminary—or alpha level—design document by Elon Musk, with substantial design assistance from an informal group of engineers at both Tesla Motors and SpaceX who worked on the conceptual foundation and modelling of Hyperloop. The preliminary design called for a steel tube, operating in partial vacuum (nearly airless), utilizing pressurized vehicle "pods" to carry passengers or cargo that would ride on an air cushion driven by linear induction motors and air compressors. The alpha design included a notional route running from the Los Angeles region to the San Francisco Bay Area, paralleling the Interstate 5 corridor for most of its length, so that preliminary economic analysis might be done on the concept.
Responses to the design paper release included: "a flash of brilliance" and "hypercool" to "nothing new here" to "hype", "another science-fiction dream," and "completely impractical."
Within days of the 2013 announcement, discussions concluded that building a successful Hyperloop subscale demonstration project could reduce the political impediments while improving cost estimates; Musk suggested that he could choose to become personally involved in building a demonstration prototype of the Hyperloop concept, including funding the development effort.
On 15 June 2015, SpaceX announced that they would sponsor a Hyperloop pod design competition, and would build a subscale test track near SpaceX's headquarters in Hawthorne, California, for the competitive event. The competition could be held as early as June 2016.
SpaceX stated in their announcement, "Neither SpaceX nor Elon Musk is affiliated with any Hyperloop companies. While we are not developing a commercial Hyperloop ourselves, we are interested in helping to accelerate development of a functional Hyperloop prototype."
More than 700 teams had submitted preliminary applications by July.
Detailed competition rules were released for the first competition in August 2015, with revisions in October.
Formal Intent to Compete submissions were due 15 September 2015 with SpaceX intending to release the detailed tube and technical specification by October 2015 but became available somewhat later.
A preliminary design briefing was held in November 2015, and , Final Design Packages were due on 13 January 2016. A Design Weekend was held at Texas A&M University on 29–30 January 2016 for all invited entrants. The selected pods will compete at the SpaceX Hyperloop Test Track in January 2017.
More than 120 student engineering teams were selected from the preliminary design briefing presentations in November to submit final design packages in January 2016. The designs were released to public view prior to the end of January 2016, and selected teams were invited to build hardware and compete in time trials, planned for mid-2016 at the time.
SpaceX announced in January 2016 that they had engaged a Los Angeles-based, Fortune-500, engineering design and construction firm AECOM, to build the Hyperloop Test Track. Triumph Group was also recognized as a major contributor to the construction efforts.
At a 29–30 January 2016 meeting at Texas A&M University, hosted by the College of Engineering, the designs from the approximately 120 worldwide teams were reviewed and judged. 30 teams were selected to go forward and build prototype Hyperloop pods for the competition later in the year.
On 30 January 2016, Musk announced that, due to the level of sophistication of the pod designs as well as design issues with economical design approaches to building the test track, "given this level of enthusiasm, there is no question we are going to have another Hyperloop competition." Further information came in August 2016: the team sign-up deadline would be 30 September 2016 to compete in the second pod competition sometime in 2017.
In the event, the mid-2016 competition schedule was delayed to January 2017. TechCrunch published a photograph of the pod competition test track still under construction in September 2016. Competition teams visited the track for fit checks and vacuum/track tests during the first week of November, and a video was released.
The on-track portion of the competition finally got underway on 27 January 2017 with 27 teams competing. WARR Hyperloop, from the Technical University of Munich won top honors.
In April 2017, 24 teams were selected to compete in Competition Weekend II. Held in August 2017, WARR Hyperloop won top honors once again, this time with a top speed in the mile-long test track.
In September 2017, SpaceX announced that they would sponsor another competition in the third quarter of 2018. As with the Competition Weekend II in 2017, only student teams may enter the competition, and the "competition will be judged solely on one criteria: [sic] maximum speed with successful deceleration (i.e. without crashing)." Unlike the two test track competitions in 2017 however, all pods must be self-propelled. SpaceX will not provide an external pusher-vehicle as they did provide to facilitate student team pod testing in both the January and August 2017 competitions. Ultra-small pods will not be allowed this time, with minimum pod length set at . There will be an additional sub-competition with up to three qualifying teams allowed to take part in a Levitation Sub-Competition that will require non-wheeled pod levitation and will be tested on an external (non-vacuum) test track. The pods will need to translate at least down the track, stop, reverse, and translate back to the original position, all while levitating the entire duration. Fastest full cycle wins the levitation sub-competition. The 2018 competition will take place 22 July 2018.
, Steve Davis—who joined SpaceX as employee no. 9 in 2003, and was then project leader for The Boring Company—had been the operations manager for the Hyperloop Pod Competition since inception.
The fourth year of competition was announced for the northern hemisphere summer of 2019, and the event was run 21 July 2019. The team from the Technical University of Munich—"Team TUM", formerly named "WARR Hyperloop"—again achieved the highest speed on the track at . Although only slightly faster than the previous year, two other teams were able to achieve high-speed runs for the first time. A total of 21 teams competed with some 700 individuals involved from the teams. Four of the teams were able to qualify for track runs.
Following the July 2019 competition, Musk announced that the 2020 competition will be run on a much longer——track that will include a curve, ten times as long as the 1 km straight track used in the first several years of the annual competition.
By November 2022, the prototype Hyperloop tunnel built for the Hyperloop pod competition in Hawthorne had been disassembled and removed.
Technical overview
Each competition has taken place on a , test track built in southern California.
Test pods may not carry any human or animal, and are to be used solely to develop new technologies and subsystems for effecting higher-velocity tube transport systems.
The track will facilitate pod test runs where each pod is accelerated, achieves a top measured speed that is reported in real-time, and then decelerates by braking, ostensibly before the end of the test track. There will be a crash pit after the end of the track to absorb the energy of any test pods that fail to come to a stop in the test track tube.
Test track
The SpaceX Hyperloop test track — or Hypertube — was designed in 2015 and was constructed in 2016, reaching its full length of one mile by October 2016. The test track itself is also a prototype, where SpaceX anticipates learning from the design, build process and evaluates how to apply automated construction techniques to future Hyperloop tracks.
The design of the pod test track varies significantly from the Hyperloop tube design shown in the initial alpha-level Hyperloop design concept document released in 2013.
The Hypertube test track is designed to enable competitors who implement a wide array of designs and build pods that will test a variety of subsystem technologies that are important to new vehicle transport systems. This will include Hyperloop-specific pods—with air-bearing suspension and low-pressure compressor designs—as well as wheeled vehicle and magnetic levitation rail designs that will support a wide array of vehicle technologies to be tested. Some pods are expected to test only particular subsystems rather than a full Hyperloop-capable pod vehicle design; as well, many pods will have no on-pod compressor to prevent the high-speed choked-flow problem, very unlike the Hyperloop alpha design.
Multiple systems were allowed for propulsion and for levitation/suspension of various team pods. Three explicit suspension types were called out in the year 1 competition rules: wheels, air bearings, and magnetic levitation. In the initial year, Pod propulsion could be On-pod—as envisioned in the alpha Hyperloop design—or for the Hypertube test track, could use a SpaceX-provided Pusher to accelerate pods up to speed in the first 15 percent of track length, or even be unique (team-specific) Off-pod propulsion systems that would need to be integrated into the Hypertube for that Pod's specific test run. In later years, the pods were required to be self-propelled.
Specifications
The test track specifications include:
Outer diameter: (vs. approximately for the tube in the initial alpha Hyperloop design document)
Inner diameter:
Wall thickness: (vs. for the tube in the initial alpha Hyperloop design)
Length: (approximate)
Materials
Tube: ASTM A1018 Grade 36 carbon steel
Rail: Aluminum 6061-T6
Subtrack: AA1370-50 Aluminum alloy for electrical applications
Concrete base inside the tube to support wheeled-vehicle pods
Subtrack thickness: for first and last ; for remainder of tube
Internal pressure: competitors may select tube operating pressure "in order to support various types of propulsion systems, compressors (if applicable), and outer mold lines"
Pumpdown time is expected to be as long as 30 minutes to reach the minimum pressure rating.
Thermal control system: none provided in the Hypertube. Tube temperature is expected to vary based on time of day and weather, and competitors will need to design their pods accordingly, mitigating thermal hotspots during pumpdown and test runs.
Braking system: the only Hypertube-provided braking is the emergency foam pit at the end of the mile-long tube. Pods are expected to provide their own pod-specific braking system, one that will react force to the Hypertube by one of four methods: either against the steel tube, or concrete base, or aluminum subtrack, or central rail. Tube requirements limit friction braking against the subtrack or rail to specified limits.
Power: none provided on the test track during testing; 240VAC/50A and 120VAC/15A power provided in the pod waiting area up through the pre-launch phase within the tube
Communications: SpaceX will provide a standard Network Access Panel (NAP) device (approximately ) for mounting on each pod which will communicate to the in-tube network via two, redundant, 1–25 GHz, wave blade antennas. The NAP will also record temperature, acceleration, vibration and shock of each pod in real time during each test run.
Navigation aids: The tube will include a series of circumferential reflective stripes applied to the inner circumference of the tube, located on the top of the tube, to be used for optical pod navigation, and in particular, awareness of the last of the tube so pod braking may be safely effected.
Vehicle pods
Three variations of exterior design are currently being explored for vehicle pods. One pod design uses air bearings; this design relies on a system to create a bed of air for the pod to glide upon and is the basis of Elon Musk's original Hyperloop idea. Another pod design uses magnetic levitation; this design was used by the winner of the "Best Overall Design Award" MIT. The third design uses high speed wheels for speeds under 100 mph and air bearings for higher speeds. This design was used by University of Colorado, Denver's Hyperlynx team.
The inside design of the pods vary by team. Some of the teams are solely building pods designed for cargo transport. Other teams designed pods to transport passengers, while other designs would allow adjustments to be made to the pod to allow both, while MIT's team's initial design did not have room for a passenger or cargo and solely relied on the engineering of the pod. The University of Colorado, Denver's team incorporated a removable capsule that allows it to be exchanged for a cargo hold or passenger space. New York University's team has created a vehicle that only allows cargo transportation.
Competitions
Competition I (January 2016 and January 2017)
Competing teams
The teams that advanced to the prototype hardware build stage for 2016 included representatives from four continents and at least six countries. The selected teams included:
AZLoop, Arizona State University, Embry–Riddle Aeronautical University, and Northern Arizona University
Hyperloop Poland University of Wroclaw and University of Warsaw
Badgerloop, University of Wisconsin–Madison
Bayou Bengals, Louisiana State University
Berkeley Hyperloop, University of California, Berkeley
Carnegie Mellon Hyperloop, air-bearing subsystem Carnegie Mellon University
Codex, pod design uses magnetic levitation suspension; team has only eight members as of February 2016. Oral Roberts University
Delft Hyperloop, Delft University of Technology
Drexel Hyperloop, building a design with air-bearing suspension and a compression braking using built-up air pressure in the Hypertube. Team is approximately 80 undergraduate students. Drexel University
Gatorloop, pod design uses wheel suspension. University of Florida
HyperBears, Baylor University
HyperLift, St. John's School (Texas) The only high school team in the competition.
Hyperloop UC, pod design used magnetic levitation, and was the first to demonstrate such technology. University of Cincinnati
Hyperloop Toronto, University of Toronto
Hyperloop at Virginia Tech V-17, Virginia Tech
HyperXite, University of California Irvine
Illini Hyperloop, has a history of previous Hyperloop design projects in the Mechanical Science and Engineering program, the first dating to the fall term of 2013. In addition to four subsystem design teams, the Illini group has a fifth, cross-disciplinary team focusing on safety and reliability, the prevention of branching failures. University of Illinois at Urbana-Champaign
Keio Alpha, Micro-pod architecture consist of active and passive magnetic levitation suspension with a passive eddy current brake. It should weigh less than 45 kg and does not need to carry dummy passenger. Keio University
Lehigh Hyperloop, Lehigh University
Hyperloop Makers UPV team Valencia, Spain, magnetic levitation based on attraction to the top of the tube. Rail-free and clean tube layout, compensation of inertial forces, reduced air-evacuation cost and up to 30% savings in infrastructure. Powered by detachable batteries, propulsion through compression and expansion of air with a nozzle. Universitat Politècnica de Valencia.
Mercury Three, University of Wisconsin, Milwaukee
MIT Hyperloop Team, magnetic levitation suspension and high speed are the design focal points. no compressor for this test pod. Massachusetts Institute of Technology
NYU Hyperloop, Slate, a freight-only pod, will use air-bearing suspension; is being designed and built by a team of, as of February 2016, fewer than ten undergraduate students. New York University
OpenLoop, pod design will use an air-bearing suspension and compressor similar to the original 2013 Hyperloop alpha design. multi-university team of Cornell University (suspension), Harvey Mudd College (control systems), University of Michigan (fuselage), Northeastern University (suspension), Memorial University of Newfoundland (compressed air), and Princeton University (electrical and cooling)
Purdue Hyperloop, Purdue University
rLoop, Inc., The only non-student team that advanced in the competition and won the "Innovation Award." Initially conceived on a Reddit forum, rLoop is now a full-fledged, funded Hyperloop initiative with activity in over 14 countries.
TAMU Aerospace Hyperloop, Texas A&M
Team Frigates, Shiv Nadar University, Undergraduate design team consisting of 8 students from different disciplines, namely Mechanical, Physics and Electronics and Communications.
Team HyperLynx, pod design uses high-speed wheel suspension, with a modular/removable payload design for a pod with a total mass of , aiming for a top speed of . University of Colorado-Denver
UCSB Hyperloop, pod design will use magnetic levitation suspension. Test runs will be accelerated by the Hypertube pusher. Undergraduate design team (senior project) of 20 members. University of California-Santa Barbara
UMD Loop, University of Maryland
USC Hyperloop, University of Southern California
UWashington Hyperloop, University of Washington
Waterloop, a Canadian team designing a pod with air levitation, magnetic brakes and control, targeted at aiming for a cruising velocity of while carrying a payload of . University of Waterloo
VicHyper, Royal Melbourne Institute of Technology
WARR Hyperloop, pod design will use an electrodynamic suspension system to levitate and an axial compressor to minimize aerodynamic drag from the residual air inside the tube when the pod is moving at high velocity. Technical University of Munich
HyperPodX, a German team with a pod designed to levitate using a series of fixed magnets following a Halbach array and a pusher with 4 electric motors for acceleration to high velocities The team comprises Engineering Physics students from the University of Oldenburg and the Hochschule Emden/Leer(de)
Phase 1: Design weekend (January 2016)
Five design awards were assigned following the January design weekend.
MIT Hyperloop Team's design was awarded received the "Best Overall Design Award", among the 23 designs selected to move to the prototype stage. The design proposes a 250 kg (551 lb) pod with a carbon fiber and polycarbonate sheet exterior. It is elevated by a passive magnetic levitation system comprising 20 neodymium magnets that will maintain a 15 mm (0.6 in) distance above the track.
The team says with air pressure at 140 Pascals, the pod could accelerate at 2.4 G and have 2 Newton aerodynamic drag when traveling at 110 m/s. The design includes a fail-safe braking system that automatically halts the pod should the actuators or computers fail, and low speed emergency drive wheels that can move the pod 1 m/s.
Delft Hyperloop received a "Pod Innovation Award",
while Badgerloop, Hyperloop at Virginia Tech, and HyperXite at UC Irvine each received a "Pod Technical Excellence Award". One award for "Best Non-Student Team" was awarded to rLoop, a team which formed on the SpaceX subreddit.
In addition to the five pod awards above, nine subsystem awards and three "design only" awards were given to teams, most to teams that were not chosen to continue on to the on-track competition.
Technical awards for outstanding technical merit in subsystem and design, based on "innovation and uniqueness of subsystem design, full Hyperloop system applicability and economics; level of design detail; strength of supporting analysis and tests; and quality of documentation and presentation."
Best Overall Subsystem Award: Auburn University Hyperloop Team, Auburn University; Safety Subsystem Technical Excellence Award: UWashington Hyperloop, University of Washington; Special Innovation Award in the Other Subsystem: RIT Imaging, Rochester Institute of Technology; :Levitation Subsystem Technical Excellence Award: TAMU Aerospace Hyperloop, Texas A&M; Braking Subsystem Technical Excellence Award: VicHyper, RMIT University; Propulsion/Compression Subsystem Technical Excellence Award: Makers UPV Team, Universitat Politècnica de València; Subsystem Technical Excellence Awards: Hyped, University of Edinburgh; Conant Hyperloop Club, Conant High School; Subsystem Innovation Award: Ryerson's International Hyperloop Team, Ryerson University.
Top Design Concept Award: Makers UPV Team (see above); Design Concept Innovation Award: Nova Hyperloop Team, University of Cairo; Design Concept Innovation Award: Auburn University Hyperloop Team (see above).
Phase 2: Test track runs (January 2017)
Phase 2 of the competition ran 27–29 January 2017 after previously being planned for as early as August 2016. 27 teams competed in two overall categories and five subcategories. Each pod in the competition needed to progress through ten sequential tests, only the last of which would be a vacuum-environment speed run in the mile-long Hypertube. Problems with dust and misalignment of the track limited performance and caused widespread problems. Just three of the competition pods successfully completed the nine tests that enabled them to make a vacuumized tube run on 29 January. The winning teams were:
Overall
Fastest Pod Award: WARR Hyperloop (Technical University of Munich)
Overall Score: Delft Hyperloop (Delft University of Technology)
Subcategory awards
Best Performance in Flight: WARR Hyperloop (Technical University of Munich)
Best Performance in Operations: UMDloop (University of Maryland, College Park)
Design and Construction: Delft Hyperloop (Delft University of Technology)
Pod Innovation Award: Badgerloop (University of Wisconsin–Madison) and rLoop (Reddit)
Safety and Reliability: MIT Hyperloop (Massachusetts Institute of Technology)
Competition II (August 2017)
The SpaceX "Hyperloop Pod Competition II" was held on 25–27 August 2017.
The rules for Competition II were released in August 2016. Unlike Competition I — where multiple judging criteria were used and multiple classes of vehicles and vehicle subsystems were judged — Competition II was judged by a single criterion: "maximum speed with successful deceleration (i.e. without crashing)."
While approximately 24 teams competed, only the top three were selected to make test runs on SpaceX's HyperTube, a 1.25-kilometer track located at the company's headquarters in Hawthorne, California.WARR Hyperloop won the competition with a test run clocked at . Paradigm won second with a top speed of . Swissloop placed third with a top speed of .
As of April 2017, 24 teams had been qualified to participate in the August 2017 competition. It is unclear how many teams actually participated.
For the 2017 competition, a Bloomberg journalist reported that entrants were required to hand over rights for SpaceX to use any of their technology in the future without compensation, but no requirement to this effect is found in the competition rules.
Competition III (July 2018)
The rules for Competition III were released in September 2017. One substantial change from Competition II was that "All Pods must be self-propelled. SpaceX [would] not provide an external Pusher" as they had on offer for teams during the first two pod competitions.
Testing week
The competition began with the testing week prior to competition weekend where teams were required to pass a series of comprehensive safety tests in order to eligible for a run in the vacuum tube.
Several teams encountered difficulties during the week, including fried circuit boards and overheated batteries. However, six teams passed the final "open-air run" and were eligible for the final competition.
Three teams (Delft Hyperloop, WARR Hyperloop, and EPFLoop) were ultimately the only final competitors.
Competition weekend
The final competition took place during the competition weekend on 22 July 2018. Each team demonstrated their respective pods while the "tube runs" took place for the final three competitors. Netherlands' Delft Hyperloop was first to make an attempt with a top speed of 142 km/h (88 mph) before stalling in the tube. Switzerland's EPFLoop was second, yet complications led to a top speed of only .
Germany's WARR Hyperloop were the defending champions, and beat their own record with a top speed of during their run. A concurrent levitation sub-competition testing the effectiveness of levitation was awarded to the University of California, Santa Barbara Hyperloop team. The other top competitors for the main competition include the University of Washington Hyperloop team and Ireland's ÉirLoop.
Competition IV (July 2019)
Teams
19 teams competed in the 2019 competition.
Key changes
Competition IV was quite similar to Competition III in most respects, with a few key changes being made.
Notably, teams used their own communications system. SpaceX did not provide an on-pod communications system, as they had in the past.
Additionally, pods were designed and tested to propel themselves within 100 feet of the far end of the tube before stopping. This change was made to eliminate the difficulties of retrieving a pod that had ended its run in the middle of the tube.
Testing week
As with previous competitions, the actual "competition weekend" was preceded by a week of comprehensive safety and function tests for each team. Teams eligible to perform a full vacuum run in the tube are selected based on the results of such tests.
Four teams were selected to run at the end of testing week: TUM Hyperloop (formerly WARR Hyperloop), Delft Hyperloop, Swissloop, and EPFLoop.
Competition weekend
During the actual competition, TUM Hyperloop was once again the victor, achieving a record top speed of , beating their previous record set in Competition III by only . TUM had hoped to achieve a speed closer to , but was stopped short of this speed as the pod suffered visible damage and was forced to emergency brake.
According to TUM Hyperloop's Instagram page, the cause of the damage was due to the derailment of one of their propulsion modules, "most likely because of a misalignment of the rail segments. With the pod consequently running too low, some of the other modules were deformed and made one of the motors hit the shell. The biggest impact occurred when one of the screws that hold the rail to the ground hit one of our brakes, ripping apart its bottom".
Tunnel-boring competition (September 2021)
While plans as of 2019 had called for another pod-racing competition in 2020—this one hoped to be on a yet-to-be-built longer track—by July 2020 Musk publicly confirmed that there would be no competition in 2020, and that no longer track had been built. Also revealed then was that they were exploring holding a competition for building the tunnel itself.
Subsequently, in 2020, a set of rules for a tunnel-boring competition were released by The Boring Company, and a competition was held in Las Vegas, Nevada in September 2021. Officially named the Not-a-Boring Competition, the competition challenge was to "quickly and accurately drill a tunnel that was -long and -wide."
Applications were received from 400 potential participants but a technical design review reduced the number to 12 teams that were invited to Las Vegas to demonstrate their engineering solution to more rapid automated boring of a small-diameter tunnel. The winning team was TUM Boring from Technical University of Munich who managed to excavate a bore while meeting the requisite safety requirements. TUM Boring used a conventional pipe-jacking method to build the tunnel but used a novel revolving pipe storage design to minimize downtime between pipe segments. The second-place team was Swissloop Tunneling who achieved a bore of .
Future
A worldwide, college-level hyperloop competition is scheduled to take place in India in February 2025 at the Discovery Campus of Thaiyur, IIT Madras. The competition will feature a 410-meter hyperloop vacuum tube built by the host university itself that is expected to be completed by September 2024, placing it among the longest hyperloop tunnels in the world. This will be the first time India will host such a competition, which earlier used to be held in the US and Europe.
See also
List of mechanical engineering awards
European Hyperloop Week
References
External links
Hyperloop Pod Award Ceremony, Hyperloop Pod Competition, Texas A&M University, 30 January 2015. (ustream video)
Elon Musk speaks at the Hyperloop Pod Award Ceremony, 30 January 2016. (video deleted)
Elon Musk's Hyperloop competition comes to Texas, The Verge, 2 February 2016 (video summary of January 2016 competition in Texas).
SpaceX's Hyperloop student contest brings out many big benefactors, Los Angeles Times, January 2016.
Bicycle/walking video of the entire length of the 82-sections of the Hypertube, December 2016.
BadgerLoop website
Hyperloop UPV website
RUMD Loop website
OpenLoop Website
DIYguru Knowledge Base
HyperPodX Oldenburg website
Swissloop Website
Challenge awards
Hyperloop
Mechanical engineering awards
Science competitions
2016 in science
2017 in science
2018 in science
Hawthorne, California
2016 in California
2017 in California
2018 in California | Hyperloop pod competition | [
"Technology",
"Engineering"
] | 6,481 | [
"Transport systems",
"Science competitions",
"Mechanical engineering awards",
"Mechanical engineering",
"Science and technology awards",
"Vacuum systems",
"Hyperloop"
] |
49,274,221 | https://en.wikipedia.org/wiki/Graphs%20and%20Combinatorics | Graphs and Combinatorics (ISSN 0911-0119, abbreviated Graphs Combin.) is a peer-reviewed academic journal in graph theory, combinatorics, and discrete geometry published by Springer Japan. Its editor-in-chief is Katsuhiro Ota of Keio University.
The journal was first published in 1985. Its founding editor in chief was Hoon Heng Teh of Singapore, the president of the Southeast Asian Mathematics Society, and its managing editor was Jin Akiyama. Originally, it was subtitled "An Asian Journal".
In most years since 1999, it has been ranked as a second-quartile journal in discrete mathematics and theoretical computer science by SCImago Journal Rank.
References
Academic journals established in 1985
Combinatorics journals
Graph theory journals
Discrete geometry journals | Graphs and Combinatorics | [
"Mathematics"
] | 163 | [
"Combinatorics journals",
"Graph theory",
"Combinatorics",
"Graph theory journals",
"Mathematical relations"
] |
49,274,252 | https://en.wikipedia.org/wiki/AC%2020-115 | The Advisory Circular AC 20-115( ), Airborne Software Development Assurance Using EUROCAE and RTCA (previously Airborne Software Assurance), recognizes the RTCA published standard DO-178 as defining a suitable means for demonstrating compliance for the use of software within aircraft systems. The present revision D of the circular identifies ED-12/DO-178 Revision C as the active revision of that standard and particularly acknowledges the synchronization of ED-12 and DO-178 at that revision.
This Advisory Circular calls attention to ED-12C/DO-178C as "an acceptable means, but not the only means," to secure FAA approval of software. The earliest revisions of the Advisory Circular were brief, serving little more than to call attention to active DO-178 revisions. The Advisory Circular revisions C and D are considerably longer, giving guidance in modifying and re-using software previously approved using DO-178, DO-178A, or DO-178B (preceding revisions of the DO-178 standard). Additionally, the expanded AC now provides guidance for Field Loadable Software and User Modifiable Software within aircraft software. Transition of legacy tool qualification from DO-178B to DO-330 is also discussed, with comparison of ED-12B/DO-178B Tool Qualification Type with ED-12C/ED-215 DO-178C/DO-330 Tool Qualification Level.
Revision History
References
External links
AC 20-115D, Airborne Software Assurance
Avionics
Safety
Software requirements
RTCA standards
Computer standards | AC 20-115 | [
"Technology",
"Engineering"
] | 309 | [
"Software requirements",
"Computer standards",
"Avionics",
"Software engineering",
"Aircraft instruments"
] |
49,274,271 | https://en.wikipedia.org/wiki/Geocoder%20%28Ruby%29 | Geocoder (Ruby) is a geocoding library for Ruby. Geocoding helps to enhance webpages by presenting location relevant information to the user. When used with Rails, Geocoder adds geocoding functionality such as finding coordinates with street addresses or vice versa in addition to distance calculations for ActiveRecord objects. Since the functionality does not rely on proprietary database functions, finding different geocoded objects in an area works out-of-the-box for databases like MySQL, PostgreSQL and SQLite.
Compatibility
Geocoder has been fully tested with Ruby 1.8.7, 1.9.2, and JRuby 1.5.3.
Geocoder is compatible with Rails 3, but there is only limited functionality with Rails 2.
Installation
The Prerequisites to installing Geocoder are Ruby and RubyGems.
Geocoder gem can be installed with the following command:
gem install geocoder
Or, if you're using Bundler for Rails, you may add this to your Gemfile:
gem 'geocoder'
and run at the command prompt:
bundle install
It can be used as a plugin with rails too:
rails plugin install git://github.com/alexreisner/geocoder.git
Configuration
In order to use Geocoder with objects, the project must be set up as follows:
Required attributes
ActiveRecord
In order to use Geocoding with ActiveRecord objects, they must have two additional attributes, latitude and longitude coordinates. When stored in the table they should be called latitude and longitude but they may be changed as explained below. When using reverse geocoding (translating a user's location coordinates into a physical address), the model must implement a method that returns an address. The address may be a single attribute; however, it can also be a method which returns a string assembled from different attributes such as city, state, and country.
Mongoid
When using Mongoid, the model only needs to add the address, latitude and longitudes as fields. The model must also include Geocoder::Model::Mongoid before making any calls to the geocoded_by: method.
Model behavior
In the rails model, Geocoder must be told which method returns the object's full address:
geocoded_by :full_street_address # can also be an IP address
after_validation :geocode # auto-fetch coordinates
For reverse geocoding, Geocoder must know which method returns latitude and longitude coordinates. If :address option is not provided, it fetches the address automatically in the address attribute. Else, it fetches the address into the location attribute like the example given below.
reverse_geocoded_by :latitude, :longitude,
:address => :location
after_validation: reverse_geocode # auto-fetch address
Forward and Reverse Geocoding on the same model is possible.
geocoded_by :address
reverse_geocoded_by :latitude, :longitude
after_validation :geocode, :reverse_geocode
In order to use different names for latitude and longitude in the model, the following change may be done when implementing geocoded_by:
geocoded_by :address, :latitude => :lat, :longitude => :lon
Additionally, the address method may return any string that would be used to search Google Maps. Any of the following examples will work:
"123 Sample St, New York, NY"
"Eiffel Tower, Paris, FR"
"Raleigh, NC, US"
Services
By default, Geocoder makes use of Google's geocoding API to retrieve addresses and coordinates. Currently, these address geocoding services are supported:
Google:
Yahoo:
Geocoder.ca: (US & Canada only)
Examples
Here are some examples to demonstrate Geocoder functionality:
Hotel.near("Raleigh, North Carolina")
Finds hotels near Raleigh.
@restaurant.distance_to("Empire State Building")
Finds the distance from @restaurant to the Empire State Building.
Applications
Developers may also use Geocoder to convert a user's IP address to their city location. By making such a conversion you may be able to offer user's content relevant to their current location without requiring to ask for it beforehand.
It may be used for geospatial analysis in order to recognize patterns within the information. This is very useful in data mining applications.
Web-based GIS tools such as Google Maps, Yahoo Maps etc. include geocoding functionality.
References
Computer programming
Articles with example Ruby code | Geocoder (Ruby) | [
"Technology",
"Engineering"
] | 964 | [
"Software engineering",
"Computer programming",
"Computers"
] |
49,274,449 | https://en.wikipedia.org/wiki/Pseudotropine | Pseudotropine (3β-tropanol, ψ-tropine, 3-pseudotropanol, or PTO) is a derivative of tropane and an isomer of tropine. Pseudotropine can be found in the Coca plant along with several other alkaloids
See also
Pseudotropine acyltransferase
Pseudotropine benzoate (tropacocaine)
Atropine
Tropine
Tropinone
References
Tropanes
Secondary alcohols | Pseudotropine | [
"Chemistry",
"Biology"
] | 105 | [
"Biochemistry stubs",
"Biotechnology stubs",
"Biochemistry"
] |
49,274,569 | https://en.wikipedia.org/wiki/O-Acylpseudotropine | An O-acylpseudotropine is any derivative of pseudotropine in which the alcohol group is substituted with an acyl group.
Acylpseudotropines are formed by the action of the enzyme pseudotropine acyltransferase on pseudotropine.
See also
Tropine
Pseudotropine benzoate (tropacocaine)
Atropine
Tropinone
References
Tropanes
Carboxylate esters | O-Acylpseudotropine | [
"Chemistry",
"Biology"
] | 96 | [
"Biochemistry stubs",
"Biotechnology stubs",
"Biochemistry"
] |
49,275,541 | https://en.wikipedia.org/wiki/Quantum%20anomalous%20Hall%20effect | Quantum anomalous Hall effect (QAHE) is the "quantum" version of the anomalous Hall effect. While the anomalous Hall effect requires a combination of magnetic polarization and spin-orbit coupling to generate a finite Hall voltage even in the absence of an external magnetic field (hence called "anomalous"), the quantum anomalous Hall effect is its quantized version. The Hall conductivity acquires quantized values proportional to integer multiples of the von Klitzing constant () (also called conductance quantum). In this respect the QAHE is similar to the quantum Hall effect. The integer here is equal to the Chern number which arises out of topological properties of the material band structure. These effects are observed in systems called quantum anomalous Hall insulators (also called Chern insulators).
The effect was observed experimentally for the first time in 2013 by a team led by Xue Qikun at Tsinghua University.
See also
Quantum Hall effect
Hall effect
References
Hall effect | Quantum anomalous Hall effect | [
"Physics",
"Chemistry",
"Materials_science"
] | 215 | [
"Physical phenomena",
"Hall effect",
"Quantum mechanics",
"Electric and magnetic fields in matter",
"Electrical phenomena",
"Solid state engineering",
"Quantum physics stubs"
] |
49,277,066 | https://en.wikipedia.org/wiki/Abies%20minor | Abies minor is a taxonomic synonym that may refer to:
Abies minor = Abies balsamea
Abies minor = Abies alba
References | Abies minor | [
"Biology"
] | 31 | [
"Set index articles on plants",
"Set index articles on organisms",
"Plants"
] |
49,277,442 | https://en.wikipedia.org/wiki/Stone%20carving%20in%20Odisha | Stone carving in Odisha is the ancient practice of sculpting stone into art and utilitarian objects. It is an ancient practice in the Indian state of Odisha. Stone carving is practiced by artisans mainly in Puri, Bhubaneswar and Lalitgiri in the Cuttack district, though some carvings can be found in Khiching in the Mayurbhanj District. Stone carving is one of the major handcrafts of Odisha. The art form primarily consists of custom carved works, with the Sun Temple of Konark and its intricate sculpture and delicate carvings on the red vivid sandstone exemplifying the practice. Other noteworthy monuments include the Stupas of Udayagiri and Ratnagiri and the temples at Jagannath, Lingaraj, Mukteshwar and as well as other temples in the region.
Stones
Sandstone, soapstone, serpentinite, Makrana marble, and granite were used in Konark stone carving. Skillful artists may use the soft, white soapstone, , or the slightly harder greenish chlorite or . Rocks such as the pinkish , or and the hardest of all, black granite and are commonly used.
Procedure
An outline of sorts is first drawn on the cut-to-size stone. Once the outline is engraved, the final figure is brought out by removing the unwanted portions. For the harder stones, this is done by chiseling out the extra material. With softer stones, it is done by scraping out the extra material with a sharp flat-edged iron tool. Hammers and chisels of various sizes are used (e.g., the , , , and ).
Products
Subjects are often traditional images, including mythological figures. Utilitarian items like candle stands, pen stands, paperweights, bookends, lamp bases and stoneware utensils are also created. Turning and polishing with a wooden lathe called Kunda, the craftsmen produce beautiful polished plates (thali), containers (gina, pathuri), cups and glasses. These are used for , ritual worships and for daily eating. Stoneware containers are particularly good for storing curd as they do not react to acid. They are also filled with water and used for holding the legs of wooden almirahs to keep out the ants.
References
Geographical indications in Odisha
Stonemasonry | Stone carving in Odisha | [
"Engineering"
] | 483 | [
"Construction",
"Stonemasonry"
] |
49,277,634 | https://en.wikipedia.org/wiki/Approximate%20computing | Approximate computing is an emerging paradigm for energy-efficient and/or high-performance design. It includes a plethora of computation techniques that return a possibly inaccurate result rather than a guaranteed accurate result, and that can be used for applications where an approximate result is sufficient for its purpose. One example of such situation is for a search engine where no exact answer may exist for a certain search query and hence, many answers may be acceptable. Similarly, occasional dropping of some frames in a video application can go undetected due to perceptual limitations of humans. Approximate computing is based on the observation that in many scenarios, although performing exact computation requires large amount of resources, allowing bounded approximation can provide disproportionate gains in performance and energy, while still achieving acceptable result accuracy. For example, in k-means clustering algorithm, allowing only 5% loss in classification accuracy can provide 50 times energy saving compared to the fully accurate classification.
The key requirement in approximate computing is that approximation can be introduced only in non-critical data, since approximating critical data (e.g., control operations) can lead to disastrous consequences, such as program crash or erroneous output.
Strategies
Several strategies can be used for performing approximate computing.
Approximate circuits
Approximate arithmetic circuits: adders, multipliers and other logical circuits can reduce hardware overhead. For example, an approximate multi-bit adder can ignore the carry chain and thus, allow all its sub-adders to perform addition operation in parallel.
Approximate storage and memory
Instead of storing data values exactly, they can be stored approximately, e.g., by truncating the lower-bits in floating point data. Another method is to accept less reliable memory. For this, in DRAM and eDRAM, refresh rate assignments can be lowered or controlled. In SRAM, supply voltage can be lowered or controlled. Approximate storage can be applied to reduce MRAM's high write energy consumption. In general, any error detection and correction mechanisms should be disabled.
Software-level approximation
There are several ways to approximate at software level. Memoization or fuzzy memoization (the use of a vector database for approximate retrieval from a cache, i.e. fuzzy caching) can be applied. Some iterations of loops can be skipped (termed as loop perforation) to achieve a result faster. Some tasks can also be skipped, for example when a run-time condition suggests that those tasks are not going to be useful (task skipping). Monte Carlo algorithms and Randomized algorithms trade correctness for execution time guarantees. The computation can be reformulated according to paradigms that allow easily the acceleration on specialized hardware, e.g. a neural processing unit.
Approximate system
In an approximate system, different subsystems of the system such as the processor, memory, sensor, and communication modules are synergistically approximated to obtain a much better system-level Q-E trade-off curve compared to individual approximations to each of the subsystems.
Application areas
Approximate computing has been used in a variety of domains where the applications are error-tolerant, such as multimedia processing, machine learning, signal processing, scientific computing. Therefore, approximate computing is mostly driven by applications that are related to human perception/cognition and have inherent error resilience. Many of these applications are based on statistical or probabilistic computation, such as different approximations can be made to better suit the desired objectives.
One notable application in machine learning is that Google is using this approach in their Tensor processing units (TPU, a custom ASIC).
Derived paradigms
The main issue in approximate computing is the identification of the section of the application that can be approximated. In the case of large scale applications, it is very common to find people holding the expertise on approximate computing techniques not having enough expertise on the application domain (and vice versa). In order to solve this problem, programming paradigms have been proposed. They all have in common the clear role separation between application programmer and application domain expert. These approaches allow the spread of the most common optimizations and approximate computing techniques.
See also
Artificial neural network
Metaheuristic
PCMOS
References
Software optimization
Computer architecture
Approximations | Approximate computing | [
"Mathematics",
"Technology",
"Engineering"
] | 853 | [
"Computer engineering",
"Computer architecture",
"Mathematical relations",
"Computers",
"Approximations"
] |
49,278,562 | https://en.wikipedia.org/wiki/Professional%20audio%20store | A professional audio store is a retail business that sells, and in many cases rents, sound reinforcement system equipment and PA system components used in music concerts, live shows, dance parties and speaking events. This equipment typically includes microphones, power amplifiers, electronic effects units (e.g., reverb and compression effects), speaker enclosures, monitor speakers, subwoofers and audio consoles (mixers). Some professional audio stores also sell sound recording equipment, DJ equipment, lighting equipment used in nightclubs and concerts and video equipment used in events, such as video projectors and screens. Some professional audio stores rent "backline" equipment used in rock and pop shows, such as stage pianos and bass amplifiers. While professional audio stores typically focus on selling new merchandise, some stores also sell used equipment, which is often the equipment that the company has previously rented out for shows and events.
Terminology
Professional audio stores are also called "pro audio stores", "pro sound stores", "sound reinforcement" companies, "PA system companies" or "audio-visual companies", with the latter name being used when a store supplies a significant amount of video equipment for events, such as video projectors and screens. Stores often use the word "professional" in their name or the description of their store, to differentiate their stores from consumer electronics stores, which sell consumer-grade loudspeakers, home cinema equipment, and amplifiers, which are designed for private, in-home use.
Products
Pro audio stores carry a range of microphones used in live sound and recording, including specialized mics such as drum mics. Stores typically carry wireless systems which enable microphones and electric instruments to be played without cables. Recording gear includes audio interfaces, studio monitors, audio recorders, studio subwoofers, analog-digital and digital-analog converters, studio power amplifiers and duplication equipment. Live sound equipment includes sound reinforcement system loudspeaker enclosures, loudspeakers, monitor speakers, power amplifiers and subwoofers. Headphone equipment includes studio and DJ headphones, headphone amplifiers and headphone mixers. Audio consoles include live sound mixers, powered mixers (which have a built-in power amplifier), unpowered mixers and digital mixers. Signal processing gear includes DI boxes, crossovers and a range a
of electronic effects, which are typically rackmountable units, including: microphone preamplifiers, electronic vocal processors, exciters, equalizers, compressors and limiters, feedback suppressors and noise gates. Some stores also sell audio software, such as DAW software, signal processing software and virtual instruments.
Other products
While some pro audio stores only sell audio equipment, others also sell products in other categories that are used in rock concerts and DJ events, such as portable stages, stage lights, par cans and light stands. Some stores sell coloured lights, lasers and strobe lights which flash, change colours and/or move according to the beat of the music; these lights are used in nightclubs and rave dance events. Some stores also sell fog machines, which are used in dances, concerts and theatre productions, often to enhance the appearance of the lighting and laser effects. Some pro audio stores sell a range of DJ equipment, such as direct drive turntables, record cartridges and styli, DJ CD players and DJ mixers.
Other services
Some professional audio stores sell the services of audio engineers, audio technicians and delivery personnel who can deliver and set up professional sound equipment and/or oversee the audio mixing of the different instruments and voices during a show or event. Some professional audio stores offer paid consulting services on professional audio issues. These consultants can come to a customer's venue, which may be a nightclub, church, conference center, auditorium or stadium, assess its professional audio needs, and recommend the types of components–speaker enclosures, mixing boards, microphone types, and so on–that would best suit this venue and the customer's budget.
See also
Music stores (these stores primarily sell musical instruments and instrument amplifiers, but most also sell some sound reinforcement system equipment)
Pawnshops (these stores often sell some used professional audio gear such as PA speakers and power amplifiers)
References
Music industry
Music technology
Sound production technology
Sound recording technology
Musical instrument retailers
audio | Professional audio store | [
"Technology"
] | 878 | [
"Recording devices",
"Sound recording technology"
] |
49,278,706 | https://en.wikipedia.org/wiki/SYSAV%20waste-to-energy%20plant | The SYSAV (Sysav South Scania Waste) waste-to-energy plant is a waste-to-energy plant in Malmö, Sweden, which treats waste from the southern province of Skåne. The plant is owned by fourteen local authorities in Skåne. In 2008, a fourth unit was built alongside engineering consultancy Ramboll, making it is one of the largest waste-to-energy plants in Northern Europe.
Overview
The SYSAV waste-to-energy plant is the most energy efficient plant in Sweden, as well as being one of the most advanced plants in the world. The plant includes four boilers, the first two of which began operation in 1973. The two advanced boilers, fitted in 2003 and 2008 respectively, are steam boilers that generate electricity and district heating.
SYSAV also have various sites throughout the province of Skåne, which are used to process, sort, store and recycle waste. Specific examples include sorting bulky waste, composting, chipping wood, recovering metals and reloading. The sites were originally designed to be landfills, but only a small portion of the waste goes to landfill at two of the sites. The sites include facilities to process household and commercial waste, using waste combustion to recover energy, biological treatment, re-use, recycling and landfill. SYSAV also have a facility for dealing with hazardous waste.
References
External links
Power stations in Sweden
Incinerators | SYSAV waste-to-energy plant | [
"Chemistry"
] | 290 | [
"Incinerators",
"Incineration"
] |
49,278,771 | https://en.wikipedia.org/wiki/GMO%20conspiracy%20theories | GMO conspiracy theories are conspiracy theories related to the production and sale of genetically modified crops and genetically modified food (also referred to as genetically modified organisms or "GMOs"). These conspiracy theories include claims that agribusinesses, especially Monsanto, have suppressed data showing that GMOs cause harm, deliberately cause food shortages to promote the use of GM food, or have co-opted government agencies such as the United States Food and Drug Administration or scientific societies such as the American Association for the Advancement of Science.
Critics charge that GMO conspiracy theories are largely promulgated by those opposing the production and sale of GMOs, and instances of unsubstantiated conspiracy theories have lately occurred in the context of public health issues that are mostly unrelated to GMOs, including the 2015–16 Zika virus outbreak and concerns over food safety at Chipotle Mexican Grill.
Context
The existence of conspiracy theories relating to the fear over GMOs has been attested to by scientists, journalists, and skeptics who oppose much anti-GMO activism. Such commentators include Michael Shermer (writer of a monthly Skeptic column series for Scientific American), Mark Lynas (an environmental activist and writer who opposed GMOs for years and recently switched positions), and Jon Entine (the founder and head of an advocacy organization dedicated to advancing the case in favor of genetic engineering in agriculture and biotechnology). Academics writing about bioethics and science communication have also taken note.
A 2013 paper published in the journal PLOS ONE found statistical evidence that linked conspiracy theorist ideation as being a significant factor in the rejection of scientific propositions about genetically engineered food. One GMO conspiracy theory was identified by biochemist Paul Christou and horticulturalist Harry Klee as a claim that development and promotion of GMOs was done by pesticide companies to cause crops to become more vulnerable to pests and therefore require more pesticides, while philosopher Juha Räikkä identified a conspiracy theory that claims the lack of any reliable scientific evidence that show harmful effects of GMOs is due not to a lack of evidence but rather to a conspiracy to hide that evidence.
Conspiracy theories involving GMOs and their promoters have been invoked in a variety of contexts. For example, in commenting on the Séralini affair, an incident that involved the retraction of a much-criticized paper which claimed harmful effects of GMOs in lab rats, American biologist PZ Myers said that anti-GMO activists were claiming the retraction was a part of "a conspiracy to Hide the Truth™". A work seeking to explore risk perception over GMOs in Turkey identified a belief among the conservative political and religious figures who were opposed to GMOs that GMOs were "a conspiracy by Jewish Multinational Companies and Israel for world domination" while a Latvian study showed that a segment of the population of that country believed that GMOs were part of a greater conspiracy theory to poison the population of the country.
A study of media rhetorical devices used in Hunan, China found that the news articles that were opposed to trials of golden rice promoted conspiracy theories "including the view that the West was using genetic engineering to establish global control over agriculture and that GM products were instruments for genocide". Likewise, a study of the rhetoric used in public policy debates about genetically modified food in Ghana showed that conspiracy theories were a feature of a civil society opposition to GMOs:Government and scientists were denying the claim that GMO was discriminatory and posed significant human health risk, as well as the call to action to do something about GMOs. Civil society adapted the counter rhetoric of insincerity, claiming that scientists had some kind of “hidden agenda” behind their claim, such as eagerness to just earn money from their patents on GMOs. It is imperative that communication on GMOs includes the underlying assumptions, the uncertainties and the probabilities associated with both best and worst case scenarios. This is a necessary condition to minimise misinformation on GMOs but may be insufficient to completely erase conspiracy theories from the minds of the public especially when scientists and government are perceived to be biased towards multinational corporations that are ostensibly preoccupied with making profits.Social critic Margit Stange contextualized certain arguments adopted by GMO conspiracy theorists as being part of the larger controversy surrounding the subject:
The corporate push for genetically modified food arouses great suspicion. Critics charge that GM food ("Frankenfood") is profitable to industry not only because it can be patented but because crop uniformity will eventually drive up pesticide demand. The charge that big food interests take advantage of poverty to open new markets for GM food is restated by conspiracy theorists, who describe a deliberate macroeconomic creation of food shortages in impoverished nations in order to open the door to GM food. The food industry's opposition to GM food labeling and precautionary measures fuels such suspicions.
This view was echoed by bioethicist Michael Reiss and moral philosopher Roger Straughan who explain in their book Improving Nature?: The Science and Ethics of Genetic Engineering that fears about the consolidation of power by a few agrochemical companies over farmers is a main argument against new genetic engineering technology in agriculture: "At its extreme, this fear belongs to the conspiracy-theory genre and, to caricature somewhat, envisages powerless farmers forced to pay ever increasing amounts to anonymous international companies who profit from the cost of the crop seed and from the cost of the herbicides used to spray them."
Political science professors Joseph Uscinski and Joseph M. Parent in their book American Conspiracy Theories summarized the people that have adopted GMO conspiracy theories thusly:Another prototypical conspiratorial movement involves those opposed to genetically modified organisms (GMO), in essence a protest against the genetic engineering of food. Not everyone who opposes GMOs is a conspiracy theorist: reasonable people can disagree about research and fail to see small groups of people covertly working against the common good. But most visible and vocal members of this movement, however, are conspiracy theorists. They believe that genetically modified foods are a corporate plot, led by the giant multinational Monsanto, to profit off unhealthy food.Uscinski, writing for Politico in the context of the 2016 United States presidential election, identified GMO conspiracy theories as one of the "honorable mentions" appended to his list of the "five most dangerous conspiracy theories of 2016". He specifically singled-out candidates Bernie Sanders and Jill Stein as promulgators. Michael Shermer and Pat Linse, writing for Skeptic magazine, specify that in terms of political ideology, "GMO conspiracy theories are embraced primarily by those on the left."
Scholars have identified ways that the internet has aided proliferation and connection between conspiracy theories including those about GMOs. For example, computer scientists Tanushree Mitra and Mattia Samory found in a 2018 study that "[to]pics [such as] “big pharma,” “vaccines,” and “GMO,” for example, decry the corruption of health services while promoting the virtues of a “natural” lifestyle." MIT Technology Review reported in February 2018 that Russian-backed disinformation campaigns were sowing public confusion about GMOs by promoting conspiracy theories.
Monsanto
A major aspect of many conspiracy theories is the fear that large agribusinesses, especially Monsanto are working to undermine the health and safety of the general public by introducing and promoting GMOs in the food supply. One claim is that Monsanto is deliberately hiding scientific evidence that GMOs are harmful. Some anti-GMO activists claimed that Monsanto infiltrated both the American Food and Drug Administration and the American Association for the Advancement of Science which is why the two organizations have supported the scientific evidence for the safety of the genetically engineered food available for human consumption. Jeffrey M. Smith is identified in the book American Conspiracy Theories as arguing that Monsanto has captured the FDA and many other countries. In the compendium Agricultural and Food Controversies, the authors who are social scientists and food scientists trace the conspiracy theory relating in particular to Monsanto back to events in the early 1990s:
There are some well-qualified dissenting scientists and a motivated group of food activists behind them, pushing back against GM food. They believe a GM crop is not substantially equivalent to traditional crops. Moreover, they believe that the FDA follows the substantial equivalence rule not because of the science, but because the FDA was corrupted by corporate influence. This is not a belief that the authors' share, but there are smart people of high character who do believe this conspiracy theory, and their side of the story deserves to be heard.
In The World According to Monsanto, author Marie-Monique Robin describes how the substantial equivalence began with a 1992 policy statement by the FDA under the leadership of a former Monsanto lawyer, who, after working in the FDA, returned to Monsanto as vice president. Her story suggests that GM regulations were the product of a revolving-door system where regulators are former and/or future employees of the company being regulated (note that some argue Monsanto wanted excess regulations to keep out competitors, but that is not Robin's story). It is not hard to imagine a company rewarding lenient regulators with a nice job, and food activists have websites listing powerful government officials and their relation to Monsanto and other corporations. If this sounds like a conspiracy theory (a term not meant as a euphemism), it is.
Belief that Monsanto is particularly problematic has inspired such actions as the March Against Monsanto and the singling out of Monsanto over other agribusinesses such as DuPont, Syngenta, Dow, BASF and Bayer, and has been identified as a salient feature of anti-GMO activism.
An example of Monsanto-based conspiracy theorizing were the claims by some anti-GMO activists that Monsanto banned GMOs from their cafeterias while promoting them for sale and consumption by the public. Anti-GMO/chemtrail blogger Barbara H. Peterson, a retired correctional officer and rancher, complained that Monsanto "has painted those of us attempting to shed light on the dangers of genetically modified/engineered organisms (GMOs) as 'conspiracy theorists'...." She went on to attack Monsanto's suggestion that sabotage could be a possible explanation for the discovery of a few plants of experimental genetically modified wheat found inexplicably growing on a farm in Oregon as being a conspiracy theory itself.
GMO cannabis hoax
A 2015 internet hoax purporting to show that Monsanto was creating genetically modified cannabis to supply to the cannabis industry. The hoax was created by satirical fake news website World News Daily Report on April 9, 2015. Monsanto created a "standing denial" of the hoax on their "Myths About Monsanto" webpage, and tweeted a disclaimer prior to the 420 holiday in 2016, and on April 20, 2017, again tweeted "Happy 4-20. Time for our yearly reminder: Monsanto has not and is not working on GMO marijuana."
Zika virus
In January 2016, concerns over a Zika virus outbreak were accompanied by claims first published on Reddit that the virus was being spread by a genetically modified mosquito. The fears were based in part because of a new mosquito abatement initiative led by Oxitec—male mosquitoes (which do not bite) are genetically modified to be sterile, and released to mate with females, resulting in no offspring, thereby reducing the Aedes aegypti mosquito population that spreads tropical diseases such as Zika. The claims were identified as "unproven" by the debunking website snopes.com.
Chipotle food safety
In the context of mid-2010s concerns over food safety at Chipotle Mexican Grill certain commentators have implied that the outbreaks of food-borne illnesses were sabotage carried out by the biotech industry in retaliation over Chipotle's removal of GMOs from their menu. The claims were identified as "unproven" by the debunking website Snopes.
Alpha-gal syndrome
In 2023, a false conspiracy theory connecting tick-borne alpha-gal syndrome (an acquired allergy to red meat) to Gates Foundation tick research was spread on social media.
Ethical criticism
In Scholars & Rogues, an online progressive political journal, David Lambert, a development program officer for the United Nations, compared the conspiracy theories supported by some in the anti-GMO movement to those supported in the anti-vaccination movement,
Like preventable childhood diseases, malnutrition is another great moral failing of our time. GMOs such as golden rice—rice modified to contain high levels of beta carotene in order to compensate for the vitamin A deficiency which kills hundreds of thousands of children around the world and blinds many more every year—and drought resistant crops, which will become increasingly vital in the global south due to climate change, have vast potential to help those who don't shop at Whole Foods. But real progress has been stymied by the paranoid and misinformed, who clamor that GMOs, which are biologically no different than "natural" foods, are somehow poisonous. Behind it all is of course an evil corporation: Monsanto.
Offering a similar critique Kavin Senapathy, a freelance writer and speaker who offers editorials from the perspective of the skeptical movement, wrote for Forbes that Both [the anti-vaccine and anti-GMO movements] cite cherry-picked, discredited, and retracted scientific studies, such as the 1998 Andrew Wakefield study linking the MMR vaccine with autism, and the 2012 Gilles-Éric Séralini rat study linking genetically engineered crops with cancer, while ignoring the vast bodies of evidence against them....
And both lead to injustice....It may seem that surely the anti-GMO movement is benign albeit wrong, innocuous compared to anti-vaccine atrocities. It may appear that it all boils down to some harmless non-GMO labels on grocery items. But it turns out there is a human cost.
The same movement that drives marketers to source non-GMO ingredients also influences regulatory bodies around the world. Crops are kept from regions in Africa where drought is a major contributor to the complex causes of malnutrition, with researchers in Tanzania forced to burn test fields of drought-tolerant corn rather than feed starving local children. Disease-resistant crops languish due to ideological regulations, with bananas resistant to xanthomonas wilt—which is threatening food security in Uganda and eastern Africa where it’s a staple crop—kept from farmers and people who need them....Philosopher Giovanni Tagliabue argued that promoters of GMO conspiracy theories were being taken advantage of by anti-environmental corporate interests:This ideological and political anti-corporate worldview, although sometimes almost paranoid, is legitimate. Yet, while I do not argue whether this attitude is good or bad, right or wrong, I maintain that the avowed anti-industrial struggle in the field of green biotechnologies not only fails to hit the supposed target, but benefits and supports a part of the industry whose products have a stronger environmental impact than rDNA cultivars; in addition, and more importantly, opposing GMOs generates heavy collateral damage to public science, agricultural progress and the poor.
See also
Brainwashing
Big Pharma conspiracy theory
Genetically modified food controversies
References
Anti-GMO movement
Genetically modified organisms
Monsanto
Health-related conspiracy theories
Science and technology-related conspiracy theories | GMO conspiracy theories | [
"Technology",
"Engineering",
"Biology"
] | 3,174 | [
"Health-related conspiracy theories",
"Genetic engineering",
"Genetically modified organisms",
"Science and technology-related conspiracy theories"
] |
49,278,852 | https://en.wikipedia.org/wiki/Samsung%20Galaxy%20TabPro%20S | The Samsung Galaxy TabPro S is a 12-inch Windows 10-based 2-in-1 PC produced and marketed by Samsung Electronics. It came in a standard version and a Gold version. The TabPro S marked the first device in the Samsung Galaxy series to run Microsoft Windows, making it a departure from the traditionally Android-powered Galaxy lineup and marked the end of the Samsung Ativ brand. Unveiled at Consumer Electronics Show 2016, alongside Samsung Notebook 9, the TabPro S was released on March 18, 2016.
Features
The tablet has a first-party keyboard attachment included. It is a folio keyboard, which means it can be in two different positions depending how the stand is set up. When closed, it has a leather-like texture to protect from normal wear and tear when traveling.
The USB Type-C Multi-port Adapter now integrates with USB-A 3.1 Port, HDMI Port and USB-C Port. It has a 128 GB solid-state drive (256 GB in the Gold version) and 4 GB RAM (8 GB in the Gold version).
The Galaxy TabPro Pen (not to be confused with the S-Pen, the traditional Samsung stylus) is a digital stylus pen that works as an input device for this Tablet. It features 1024 pressure levels. It can be seamlessly paired via Bluetooth. It uses rechargeable battery instead of disposable AAAA battery, which allows the digital stylus pen's battery to be recharged via Micro USB 2.0 Port. the initial charge last up to 30 days.
Samsung Flow is the fingerprint access application. It can also be paired with a phone via Bluetooth and NFC tag. With this, users can unlock the tablet with their phone's fingerprint sensor.
Although the Samsung Galaxy Book was unveiled at MWC 2017, and features several improvements over the TabPro S model, it is not considered a direct successor.
See also
Samsung Galaxy Tab Pro
Samsung Galaxy Book
References
External links
Samsung Galaxy Tab series | Samsung Galaxy TabPro S | [
"Technology"
] | 415 | [
"Computing stubs",
"Computer hardware stubs"
] |
49,280,110 | https://en.wikipedia.org/wiki/Frost%20damage%20%28construction%29 | Frost damage is caused by moisture freezing in the construction. Frost damage can occur as cracks, stone splinters and swelling of the material.
When water freezes, the volume of water increases by 9 %. When the volumetric moisture content exceeds 91 %, then the volume increase of water in the pores of the material caused by freezing cannot be absorbed by sufficient empty pores. This causes an increase in the internal pressure. If this pressure exceeds the tensile strength of the material, then micro-cracks occur. Visible frost damage develops after an accumulation of micro-cracks as a result of several freeze-thaw cycles.
Frost damage can be prevented by the use of frost-proof materials, i.e., a material which has sufficient closed pores, by which the volume increase caused by the freezing of water in capillary pores can be absorbed by the ice-free closed pores.
Concrete
Frost damage of early-age concrete is particularly harmful for the concrete mechanical resistance because the ice volume expansion causes micro-cracks in the concrete structures, and as a consequence it lowers the compressive strength of concrete. Therefore, when concreting at cold temperature cannot be avoided, it is essential to have a minimum curing time at a temperature sufficiently above the freezing point of the concrete pore water, so that the early strength of concrete is high enough to resist the inner tensile stress caused by water freezing.
See also
Frost weathering
Ice thermal expansion
Sources
References
Bibliography
Goesten A.J.P.M. (2016). Hygrothermal simulation model: Damage as a result of insulating historical buildings. Eindhoven University of Technology.
ter Bekke T. (2001). Vochttransport in monumentaal metselwerk. Eindhoven University of Technology.
This article is a translation of the corresponding article on the Dutch Wikipedia.
Construction
Concrete
Water ice
Weathering | Frost damage (construction) | [
"Engineering"
] | 388 | [
"Structural engineering",
"Concrete",
"Construction"
] |
49,281,083 | https://en.wikipedia.org/wiki/The%20Data%20Incubator | The Data Incubator is a data science education company. It offers corporate data science training and placement services. It is best known for an 8-week educational fellowship preparing students with Master's degrees and PhDs for careers in big data and data science.
Founding
The Data Incubator was founded in 2014 in New York City by Tianhui Michael Li, a former data scientist at local-mobile-social startup Foursquare and Andreessen Horowitz. The company was incubated by Cornell Tech.
The company is best known for an 8-week educational fellowship preparing students with Masters and PhD degrees for careers in big data and data science. The fellowship's expenses are paid for by hiring companies and it remains free for admitted fellows. The program is no longer free, the Data Science program costs 10k for Online and 18K for in-person program. The program has four campuses: New York City, Washington DC, San Francisco, and Online. The program also offers corporate training to Fortune 500 clients.
According to Venture Beat, the program had over 1000 applicants from over 80 universities in its first round and accepted just under 3% of all applicants. The program was selected by Business Insider as one of 15 competitive programs in the world with more competitive admissions than Harvard.
Growth
In 2015, the program launched in Washington, DC and San Francisco. In December 2015, the program established their first international campus in collaboration with The Center of Applied Data Science in Kuala Lumpur, Malaysia with support from the national government.
In 2015 The Data Incubator was ranked second by Data Economy for data science incubators.
In April 2016, the program was launched in the United Kingdom with government support through The Data Lab.
In March, 2018, the company announced a partnership with SAP Fieldglass's Digital Network. The partnership provides Fieldglass's Digital Network with highly sought-after data science talent.
Data Science in 30 Minutes Online Lecture Series
The company hosts an ongoing online lecture series entitled "Data Science in 30 Minutes" featuring leading figures in data science and big data. Participants include:
scikit-learn core contributor and NYU researcher Andreas Mueller
SIGKDD and KDD founder Gregory Piatetsky-Shapiro
Stanford Professor and Databricks founder Matei Zaharia.
New York Times Pulitzer-nominated journalist Alan Schwarz
Booz Allen Hamilton Principal Data Scientist Kirk Borne
References
External links
Data Science Fellowship Program
Data Science Foundations Program
Computer science education
Coding schools
Universities and colleges in Manhattan
Organizations based in New York City
Companies based in New York City
American companies established in 2014
Organizations based in San Francisco
Education companies of the United States
Training companies of the United States
International educational organizations
Companies based in Washington, D.C. | The Data Incubator | [
"Technology"
] | 544 | [
"Computer science education",
"Computer science"
] |
49,282,028 | https://en.wikipedia.org/wiki/List%20of%20data%20breaches | This is a list of reports about data breaches, using data compiled from various sources, including press reports, government news releases, and mainstream news articles. The list includes those involving the theft or compromise of 30,000 or more records, although many smaller breaches occur continually. Breaches of large organizations where the number of records is still unknown are also listed. In addition, the various methods used in the breaches are listed, with hacking being the most common.
Most reported breaches are in North America, at least in part because of relatively strict disclosure laws in North American countries. 95% of data breaches come from government, retail, or technology industries. It is estimated that the average cost of a data breach will be over $150 million by 2020, with the global annual cost forecast to be $2.1 trillion. As a result of data breaches, it is estimated that in first half of 2018 alone, about 4.5 billion records were exposed. In 2019, a collection of 2.7 billion identity records, consisting of 774 million unique email addresses and 21 million unique passwords, was posted on the web for sale. In January 2024, a data breach dubbed the "mother of all breaches" was uncovered. Over 26 billion records, including some from Twitter, Adobe, Canva, LinkedIn, and Dropbox, were found in the database. No organization immediately claimed responsibility.
In August 2024, one of the largest data security breaches was revealed. It involved the background check databroker, National Public Data and exposed the personal information of nearly 3 billion people.
List of data breaches involving a government or public entity
List of data breaches involving companies
See also
List of cyberattacks
List of phishing incidents
List of security hacking incidents
References
Breaches
Cyberwarfare
Internet privacy
Internet vigilantism
Crime-related lists
Internet-related lists | List of data breaches | [
"Technology",
"Engineering"
] | 384 | [
"Computing-related lists",
"Cybersecurity engineering",
"Data security",
"Internet-related lists"
] |
49,283,348 | https://en.wikipedia.org/wiki/PZ-90 | PZ-90 (short for Parametry Zemli 1990 goda, in ) is a geodetic datum defined for use in the GLONASS system.
Revisions
PZ-90.02
Creation date - 2005; Epoch - 2002.0; Absolute positional accuracy - from 0.3 to 0.5 m; Relative positional accuracy - from 2 to 3 cm
PZ-90.11
Creation date - 2011; Epoch - 2010.0; Absolute positional accuracy - 5 cm; Relative positional accuracy - from 0.5 to 1 cm
PZ-90.11 is described as "closest to ITRF2000" by the ESA's Navipedia. It converts to ITRF2008 with only a shift vector; no rotation or scaling is needed.
References
GLONASS
Geography of Russia | PZ-90 | [
"Mathematics",
"Technology"
] | 171 | [
"Wireless locating",
"GLONASS",
"Geodetic datums",
"Coordinate systems"
] |
49,286,295 | https://en.wikipedia.org/wiki/Wardomyces%20moseri | Wardomyces moseri is a species of mold in the family Microascaceae. It was described as new to science by Walter Gams in 1995. The specific epithet honours mycologist Meinhard Moser "on the occasion of his 70th birthday". The type locality was a riverbank in the savanna area east of Villavicencio, Colombia. The fungus was discovered growing on a dead petiole of moriche palm (Mauritia flexuosa). It differs from other Wardomyces by having conidia that are readily liberated.
References
External links
Microascales
Fungi of Colombia
Fungi described in 1995
Fungus species | Wardomyces moseri | [
"Biology"
] | 132 | [
"Fungi",
"Fungus species"
] |
49,286,442 | https://en.wikipedia.org/wiki/Peziza%20moseri | Peziza moseri is a species of cup fungus belonging to the family Pezizaceae. It was officially described as new to science in 1974 from collections made in Israel. Fruit bodies are purple and cup-shaped, measuring in diameter. It fruits singly or in groups on burnt ground in coniferous forests.
References
External links
Pezizaceae
Fungi described in 1974
Fungi of Europe
Fungi of Western Asia
Fungus species | Peziza moseri | [
"Biology"
] | 87 | [
"Fungi",
"Fungus species"
] |
49,286,540 | https://en.wikipedia.org/wiki/NMR-STAR%20file%20format | NMR-STAR is an extension of the STAR file format to store the results of biological NMR experiments.
Chemical file formats | NMR-STAR file format | [
"Chemistry"
] | 27 | [
"Chemistry software",
"Theoretical chemistry stubs",
"Computational chemistry stubs",
"Computational chemistry",
"Physical chemistry stubs",
"Chemical file formats"
] |
53,142,858 | https://en.wikipedia.org/wiki/Cheves%20Walling | Cheves Walling (1916 – June 18, 2007) was an American organic chemist, having been a Distinguished Professor Emeritus at and also the former Editor-in-Chief of Journal of the American Chemical Society. He was also a Fellow of the National Academy of Sciences and American Academy of Arts & Sciences.
References
1916 births
2007 deaths
American organic chemists
University of Utah faculty
20th-century American chemists
Members of the United States National Academy of Sciences
Fellows of the American Academy of Arts and Sciences | Cheves Walling | [
"Chemistry"
] | 100 | [
"Organic chemists",
"American organic chemists"
] |
53,143,237 | https://en.wikipedia.org/wiki/RFinder | RFinder ("repeater finder") is a subscription-based website and mobile app. RFinder's main service is the World Wide Repeater Directory (WWRD), which is a directory of amateur radio repeaters. RFinder is the official repeater directory of several amateur radio associations. RFinder has listings for several amateur radio modes, including FM, D-STAR, DMR, and ATV.
World Wide Repeater Directory
Repeaters are listed in the directory along with its call sign, Maidenhead Locator System and GPS coordinates, transmit/receive offset ("split"), CTCSS and DCS squelch settings, and VoIP settings (IRLP and Echolink nodes). The directory has over 50,000 repeater listings in over 170 countries.
Website
The RFinder website has several search options including for routes.
Forums
RFinder user forums is for help and support for the app and hardware.
Mobile app
RFinder has mobile apps for Android and iOS. When using the mobile app, RFinder can display the distance to repeaters, based on the mobile device's current location.
ARRL Repeater Directory
The ARRL publishes the ARRL Repeater Directory which contains over 31,000 repeater listings for the US and Canada with listings provided by RFinder.
Subscription
RFinder requires a subscription. A one-year subscription is US$12.99.
Radio programming software
Some radio programming software applications can query RFinder and download repeater listing to program radios. Compatible software includes:
CHIRP
RT Systems
Radio associations
RFinder is the official repeater directory of the following associations:
Amateur Radio Society Italy
American Radio Relay League
Cayman Amateur Radio Society
Deutscher Amateur Radio Club
Federacion Mexicana de Radio Experimentadores
L’association Réseau des Émetteurs Français
Lietuvos Radijo Mėgėjų Draugija
Liga de Amadores Brasilieros de Radio Emissão
Radio Amateurs of Canada
Radio Society of Great Britain
Rede dos Emissores Portugueses
Unión de Radioaficionados Españoles
References
External links
Official website
Amateur radio
Maidenhead
Mobile applications
Subscription services | RFinder | [
"Technology"
] | 447 | [
"Mobile software stubs",
"Mobile technology stubs"
] |
53,144,610 | https://en.wikipedia.org/wiki/NGC%20414 | NGC 414 is a pair of lenticular galaxies (PGC 4254 and PGC 93079) of types S0 and E/S0, respectively, located in the constellation Pisces. It was discovered on October 22, 1867 by Herman Schultz. It was described by Dreyer as "very faint, small, irregularly round, much brighter middle, II 220 to the northwest.", with II 220 being NGC 410.
References
External links
0414
18671022
Pisces (constellation)
Lenticular galaxies
Discoveries by Herman Schultz (astronomer)
004254 | NGC 414 | [
"Astronomy"
] | 119 | [
"Pisces (constellation)",
"Constellations"
] |
53,144,687 | https://en.wikipedia.org/wiki/NGC%20415 | NGC 415 is a spiral galaxy of type SB(rb)b located in the constellation Sculptor. It was discovered on September 1, 1834 by John Herschel. It was described by Dreyer as "very faint, small, round, gradually a little brighter middle."
References
External links
0415
18340901
Sculptor (constellation)
Barred spiral galaxies
004161 | NGC 415 | [
"Astronomy"
] | 76 | [
"Constellations",
"Sculptor (constellation)"
] |
53,144,876 | https://en.wikipedia.org/wiki/Canon%20X-07 | Canon X-07 is one of the first personal computers available in France manufactured by Canon.
This is a laptop (or rather hand-held) based around the NSC800 (compatible with Z80) shipping Microsoft BASIC.
The specifications included:
memory extensions or independent IC card
parallel and serial port with an infrared extension X-721
X-711 thermal printer or plotter 4-color X-710 or standard // printer.
ROM card software (spreadsheet, monitor ...)
X-720 video interface for connection to a TV
save to cassette
Size: 30x30x11cm
References
Computing by computer model
Canon computers
Personal computers
Computer-related introductions in 1983 | Canon X-07 | [
"Technology"
] | 140 | [
"Computers",
"Computing by computer model"
] |
53,145,358 | https://en.wikipedia.org/wiki/Isabelle%20Vernos | Isabelle Vernos is an ICREA research professor at the Center for Genomic Regulation in Barcelona. She received a PhD in biochemistry from the Autonomous University of Madrid followed by postdoctoral studies at Cambridge University. Between 1992 and 2005 she developed her research career at the European Molecular Biology Laboratory at the University of Heidelberg in Germany. Since 2005 she is an ICREA Research Professor at the Center for Genomic Regulation in Barcelona where she leads the group on Microtubule Function and Cell Division, the same year she also became a member of the European Molecular Biology Laboratory. In 2012 she was chosen to be part of the Spanish Secretary of State Advisory Council on Science, Technology and Innovation, an institution formed by scientists and social agencies to advise on development policies and scientific innovation and where she is the only woman. Since 2014 she has been a member of the scientific council of the European Research Council, the institution responsible for promoting high-level research in Europe.
References
Year of birth missing (living people)
Living people
Spanish biochemists
Spanish women chemists
Autonomous University of Madrid alumni
Academic staff of Heidelberg University | Isabelle Vernos | [
"Chemistry"
] | 217 | [
"Biochemistry stubs",
"Biochemists",
"Biochemist stubs"
] |
53,145,360 | https://en.wikipedia.org/wiki/RoundMe | RoundMe was a virtual tour application which allowed users to create, upload and share 360 degree panoramic photos and multimedia content of real spaces, that users could visit virtually using Google Cardboard or any VR headsets. The app was available on the web, iOS and Android. Roundme was positioned as one of the Best New Apps in the iTunes App Store in 58 countries in 2015. Roundme raised a $3 million round led by April Capital in 2015, reportedly by TechCrunch. The company was also hosting spaces for brands including National Library of Belarus and American Airlines.
History
RoundMe was founded in June 2012 by Konstantin Andreev. It was officially released on June 17, 2014. It was headquartered in Los Angeles, California. Talking to TechCrunch, Konstantin Andreev, CEO said, that his goal was to create the best virtual tour experience in the panoramic photography marketplace.
In January 2023, RoundMe was discontinued.
See also
Giphy
Instagram
Flickr
Vine
Bazaart
References
External links
IOS software
Android (operating system) software
Companies based in Los Angeles
Internet properties established in 2014
Photo software
Mobile software
2014 software
2015 software
Social networking services | RoundMe | [
"Technology"
] | 237 | [
"Mobile software stubs",
"Mobile technology stubs"
] |
53,145,642 | https://en.wikipedia.org/wiki/Lakawood | Lakawood, or laka wood (), is a reddish aromatic heartwood used as incense in China, India and South East Asia. It also had a number of other uses in the past, for example as a dye and for medicinal purposes. The name lakawood can refer to the wood of different plants, such as Acronychia pedunculata, A. Laurifolia, and in particular, Dalbergia parviflora found in South East Asia. Historically it was one of the most commonly-traded commodities of South East Asia in the trade between China and South East Asia from the Song dynasty onwards, possibly earlier.
Names
The lakawood of Dalbergia parviflora is a product of the Malay Peninsula and Archipelago, and its native name in Malay is kayu laka (literally "laka wood"), from which the words cayolaque and lakawood are derived. In old Javanese literature, the word "laka" was also used to denote a shade of red on cloth, and the word manglaka meant "processor of laka-wood dye", although the tree from which the dye was derived from is Emblica officinalis. It is also called akar laka.
In Chinese, lakawood may be called jiangzhenxiang (降真香) or zitengxiang (紫藤香). The two names referred to different types of fragrant wood in the early period, but by the early 13th century, the two names were regarded as referring to the same product. The older term ziteng (紫藤, literally "purple vine", note that this is distinct from wisteria which has the same name in Chinese) has been identified as a plant grown in Southern China Acronychia pedunculata and A. Laurifolia. The fragrance from the wood was particularly appreciated by Taoists, and it therefore gained the name jiangzhenxiang meaning "the incense that summons the Perfected Ones to descend among us". Historical records however used two similar terms, jiangzhenxiang and jiangzhen, which may have been two different products. The fragrance and appearance of the heartwood and root wood from Dalbergia parviflora of South East Asia, known to have been imported into China in the 10th century, is similar to the earlier Chinese incense wood, it therefore became a substitute for the Chinese product.
Lakawood was also once referred to as Tanarius major in some English sources.
Uses
The wood has been used as incense in China from an early period, and it was said to be particularly favoured by the Taoists. It is powdered and mixed with other substances to make incense, commonly in the form of joss sticks. It was first mentioned in 304 AD as a preservative in wine and an incense wood for the summoning of spirit. During the Tang dynasty, it was used for magical and medicinal purposes, burnt in home to rid of all that is "weird and strange", and pieces of the wood were attached to children to ward off "evil vapours". The wood of Dalbergia parviflora has no smell until it is burnt, and only a small amount is used in joss sticks due to its strong aroma. According to 16th century herbologist and doctor Li Shizhen, it was also used "as an astringent, as a wash to cleanse sores and to excite granulations, and as a deodorizing and disinfecting agent."
The sap of Emblica officinalis, also called laka, was used as a red dye by people of Java and the Malacca Strait area. According to Zhu Fan Zhi, the red-coloured sap of lakawood was once used as an ingredient in a product called "imitation dragon's blood" (imitation of a product from Dracaena cinnabari).
The essential oils found in Dalbergia parviflora are nerolidol, farnesol, furfurol, aryl-benzofurans, and neoflavonoids.
Historical records
Ziteng was first described in 304 AD in a book on plants, Nanfang Caomu Zhuang (Plants of the Southern Regions) written by Ji Han, as having long and slender leaves, white flower and black seed. Its wood was chopped up and used as incense. The 9th century Tang poet Cao Tang (曹唐) wrote a poem on a Taoist theme that refers to the lakawood jiangzhenxiang: "Reddish dew gives me an image of upturning "the wine which extends life", Whitish smoke puts me in mind the burning of "jiangzhenxiang" ("the aromatic which brings down the True Ones")".
Lakawood from South East Asia was first noted in 982 (early Song dynasty) as one of the 37 foreign products that could be freely traded in China. Descriptions of lakawood and its trade are given in accounts from the Sung and Yuan dynasty, Zhu Fan Zhi and Daoyi Zhilüe. These texts indicate that Lakawood was a product of various states in the Malay Peninsula, Singapore, Sumatra, Java, as well as Borneo. Daoyi Zhilüe also listed laka-wood as an export of the large-scale chiefdoms at Ma-li-lu (Maynila), Sulu (later the Sultanate of Sulu), and Min-to-lang (later the Sultanate of Maguindanao) in the modern-day Philippines. They suggest a significant trade in lakawood, but it was also regarded as a cheap import during the Song dynasty, such that people of Quanzhou be they rich or poor can afford to buy the incense to burn at the end of the year as a sacrifice to Heaven. Lambri in Sumatra was mentioned as producing the best quality lakawood. Laka wood is also mentioned by Zhou Daguan in his book The Customs of Cambodia describing his trip in 1297. The value of lakawood however increased during the Ming dynasty. The product was mentioned in accounts of Zheng He's voyages such Yingya Shenglan by Ma Huan during the Ming dynasty, and its value was considered high enough to be presented to the imperial court as tributes by various ports of Sumatra as well as Siam.
References
Wood
Incense material
Plant common names | Lakawood | [
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53,145,866 | https://en.wikipedia.org/wiki/Unsuccessful%20transfer | Unsuccessful transfer or abortive transfer is any bacterial DNA transfer from donor cells to recipient cells that fails to be replicated during cell division. (In other words, the incoming DNA does not become inherited.) This may be due to:
Failure of the incoming DNA to form a circular molecule or to integrate into one;
Loss of a maintenance system (see plasmid partition system).
As a result of the abortive transfer, among all daughter cells of the recipient cell, only one cell will be holding the transferred DNA. Genes that are located on an abortively transferred piece of DNA can still express in the recipient cell.
Abortive transfer can happen after transduction, transformation, or conjugation -- all of the three main types of genetic exchange in bacteria. Abortive transduction is especially frequent.
Dictionary definition
Rieger, Michaelis, and Green, in 1976 stated:
See also
Gene expression
Plasmid
Transduction
References
Molecular genetics
Gene expression | Unsuccessful transfer | [
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53,147,574 | https://en.wikipedia.org/wiki/Bacterial%20recombination | Bacterial recombination is a type of genetic recombination in bacteria characterized by DNA transfer from one organism called donor to another organism as recipient. This process occurs in three main ways:
Transformation, the uptake of exogenous DNA from the surrounding environment.
Transduction, the virus-mediated transfer of DNA between bacteria.
Conjugation, the transfer of DNA from one bacterium to another via cell-to-cell contact.
The final result of conjugation, transduction, and/or transformation is the production of genetic recombinants, individuals that carry not only the genes they inherited from their parent cells but also the genes introduced to their genomes by conjugation, transduction, and/or transformation.
Recombination in bacteria is ordinarily catalyzed by a RecA type of recombinase. These recombinases promote repair of DNA damages by homologous recombination.
The ability to undergo natural transformation is present in at least 67 bacterial species. Natural transformation is common among pathogenic bacterial species. In some cases, the DNA repair capability provided by recombination during transformation facilitates survival of the infecting bacterial pathogen. Bacterial transformation is carried out by numerous interacting bacterial gene products.
Evolution
Evolution in bacteria was previously viewed as a result of mutation or genetic drift. Today, genetic exchange, or gene transfer is viewed as a major driving force in the evolution of prokaryotes. This driving force has been widely studied in organisms like E. coli. Bacteria reproduces asexually, where daughter cells are clones of the parent. This clonal nature leads to random mutations that occur during DNA replication that potentially helps bacteria evolve. It was originally thought that only accumulated mutations helped bacteria evolve. In contrast, bacteria also import genes in a process called homologous recombination, first discovered by the observation of mosaic genes at loci encoding antibiotic resistance. The discovery of homologous recombination has made an impact on the understanding of bacterial evolution. The importance of evolution in bacterial recombination is its adaptivity. For example, bacterial recombination has been shown to promote the transfer of multi drug resistance genes via homologous recombination that goes beyond levels purely obtained by mutation.
Mechanisms of bacterial recombination
Bacterial recombination undergoes various different processes. The processes include: transformation, transduction, conjugation and homologous recombination. Homologous recombination relies on cDNA transferring genetic material. Complementary DNA sequences transport genetic material in the identical homologous chromosomes. The paternal and maternal paired chromosomes will align in order for the DNA sequences to undergo the process of crossing over. Transformation involves the uptake of exogenous DNA from the encircling environment. DNA fragments from a degraded bacterium will transfer into the surrounding, competent bacterium resulting in an exchange of DNA from the recipient. Transduction is associated with viral-mediated vectors transferring DNA material from one bacterium to another within the genome. Bacterial DNA is placed into the bacteriophage genome via bacterial transduction. In bacterial conjugation, DNA is transferred via cell-to-cell communication. Cell-to-cell communication may involve plasmids that allow for the transfer of DNA into another neighboring cell. The neighboring cells absorb the F-plasmid (fertility plasmid: inherited material that is present in the chromosome). The recipient and donor cell come into contact during a F-plasmid transfer. The cells undergo horizontal gene transfer in which the genetic material is transferred.
Mechanisms for double-stranded breaks
The RecBCD pathway in homologous recombination repairs the double-strand breaks in DNA that has degraded in bacteria. Base pairs attached to the DNA strands go through an exchange at a Holliday junction. In the second step of bacterial recombination, branch migration. involves the base pairs of the homologous DNA strands to continuously be interchanged at a Holliday junction. This results in the formation of two DNA duplexes. The RecBCD pathway undergoes helicase activity by unzipping the DNA duplex and stops when the nucleotide sequence reaches 5′-GCTGGTGG-3′. This nucleotide sequence is known as the Chi site. RecBCD enzymes will change after the nucleotide sequence reaches the Chi site. The RecF pathway repairs the degradation of the DNA strands.
See also
Genetic recombination
References
Gene expression
Modification of genetic information | Bacterial recombination | [
"Chemistry",
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] | 929 | [
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53,147,698 | https://en.wikipedia.org/wiki/Metascience | Metascience (also known as meta-research) is the use of scientific methodology to study science itself. Metascience seeks to increase the quality of scientific research while reducing inefficiency. It is also known as "research on research" and "the science of science", as it uses research methods to study how research is done and find where improvements can be made. Metascience concerns itself with all fields of research and has been described as "a bird's eye view of science". In the words of John Ioannidis, "Science is the best thing that has happened to human beings... but we can do it better."
In 1966, an early meta-research paper examined the statistical methods of 295 papers published in ten high-profile medical journals. It found that "in almost 73% of the reports read... conclusions were drawn when the justification for these conclusions was invalid." Meta-research in the following decades found many methodological flaws, inefficiencies, and poor practices in research across numerous scientific fields. Many scientific studies could not be reproduced, particularly in medicine and the soft sciences. The term "replication crisis" was coined in the early 2010s as part of a growing awareness of the problem.
Measures have been implemented to address the issues revealed by metascience. These measures include the pre-registration of scientific studies and clinical trials as well as the founding of organizations such as CONSORT and the EQUATOR Network that issue guidelines for methodology and reporting. There are continuing efforts to reduce the misuse of statistics, to eliminate perverse incentives from academia, to improve the peer review process, to systematically collect data about the scholarly publication system, to combat bias in scientific literature, and to increase the overall quality and efficiency of the scientific process. As such, metascience is a big part of methods underlying the Open Science Movement.
History
In 1966, an early meta-research paper examined the statistical methods of 295 papers published in ten high-profile medical journals. It found that, "in almost 73% of the reports read ... conclusions were drawn when the justification for these conclusions was invalid." A paper in 1976 called for funding for meta-research: "Because the very nature of research on research, particularly if it is prospective, requires long periods of time, we recommend that independent, highly competent groups be established with ample, long term support to conduct and support retrospective and prospective research on the nature of scientific discovery". In 2005, John Ioannidis published a paper titled "Why Most Published Research Findings Are False", which argued that a majority of papers in the medical field produce conclusions that are wrong. The paper went on to become the most downloaded paper in the Public Library of Science and is considered foundational to the field of metascience. In a related study with Jeremy Howick and Despina Koletsi, Ioannidis showed that only a minority of medical interventions are supported by 'high quality' evidence according to The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Later meta-research identified widespread difficulty in replicating results in many scientific fields, including psychology and medicine. This problem was termed "the replication crisis". Metascience has grown as a reaction to the replication crisis and to concerns about waste in research.
Many prominent publishers are interested in meta-research and in improving the quality of their publications. Top journals such as Science, The Lancet, and Nature, provide ongoing coverage of meta-research and problems with reproducibility. In 2012 PLOS ONE launched a Reproducibility Initiative. In 2015 Biomed Central introduced a minimum-standards-of-reporting checklist to four titles.
The first international conference in the broad area of meta-research was the Research Waste/EQUATOR conference held in Edinburgh in 2015; the first international conference on peer review was the Peer Review Congress held in 1989. In 2016, Research Integrity and Peer Review was launched. The journal's opening editorial called for "research that will increase our understanding and suggest potential solutions to issues related to peer review, study reporting, and research and publication ethics".
Fields and topics of meta-research
Metascience can be categorized into five major areas of interest: Methods, Reporting, Reproducibility, Evaluation, and Incentives. These correspond, respectively, with how to perform, communicate, verify, evaluate, and reward research.
Methods
Metascience seeks to identify poor research practices, including biases in research, poor study design, abuse of statistics, and to find methods to reduce these practices. Meta-research has identified numerous biases in scientific literature. Of particular note is the widespread misuse of p-values and abuse of statistical significance.
Scientific data science
Scientific data science is the use of data science to analyse research papers. It encompasses both qualitative and quantitative methods. Research in scientific data science includes fraud detection and citation network analysis.
Journalology
Journalology, also known as publication science, is the scholarly study of all aspects of the academic publishing process. The field seeks to improve the quality of scholarly research by implementing evidence-based practices in academic publishing. The term "journalology" was coined by Stephen Lock, the former editor-in-chief of The BMJ. The first Peer Review Congress, held in 1989 in Chicago, Illinois, is considered a pivotal moment in the founding of journalology as a distinct field. The field of journalology has been influential in pushing for study pre-registration in science, particularly in clinical trials. Clinical-trial registration is now expected in most countries.
Reporting
Meta-research has identified poor practices in reporting, explaining, disseminating and popularizing research, particularly within the social and health sciences. Poor reporting makes it difficult to accurately interpret the results of scientific studies, to replicate studies, and to identify biases and conflicts of interest in the authors. Solutions include the implementation of reporting standards, and greater transparency in scientific studies (including better requirements for disclosure of conflicts of interest). There is an attempt to standardize reporting of data and methodology through the creation of guidelines by reporting agencies such as CONSORT and the larger EQUATOR Network.
Reproducibility
The replication crisis is an ongoing methodological crisis in which it has been found that many scientific studies are difficult or impossible to replicate. While the crisis has its roots in the meta-research of the mid- to late 20th century, the phrase "replication crisis" was not coined until the early 2010s as part of a growing awareness of the problem. The replication crisis has been closely studied in psychology (especially social psychology) and medicine, including cancer research. Replication is an essential part of the scientific process, and the widespread failure of replication puts into question the reliability of affected fields.
Moreover, replication of research (or failure to replicate) is considered less influential than original research, and is less likely to be published in many fields. This discourages the reporting of, and even attempts to replicate, studies.
Evaluation and incentives
Metascience seeks to create a scientific foundation for peer review. Meta-research evaluates peer review systems including pre-publication peer review, post-publication peer review, and open peer review. It also seeks to develop better research funding criteria.
Metascience seeks to promote better research through better incentive systems. This includes studying the accuracy, effectiveness, costs, and benefits of different approaches to ranking and evaluating research and those who perform it. Critics argue that perverse incentives have created a publish-or-perish environment in academia which promotes the production of junk science, low quality research, and false positives. According to Brian Nosek, "The problem that we face is that the incentive system is focused almost entirely on getting research published, rather than on getting research right." Proponents of reform seek to structure the incentive system to favor higher-quality results. For example, by quality being judged on the basis of narrative expert evaluations ("rather than [only or mainly] indices"), institutional evaluation criteria, guaranteeing of transparency, and professional standards.
Contributorship
Studies proposed machine-readable standards and (a taxonomy of) badges for science publication management systems that hones in on contributorship – who has contributed what and how much of the research labor – rather that using traditional concept of plain authorship – who was involved in any way creation of a publication. A study pointed out one of the problems associated with the ongoing neglect of contribution nuanciation – it found that "the number of publications has ceased to be a good metric as a result of longer author lists, shorter papers, and surging publication numbers".
Assessment factors
Factors other than a submission's merits can substantially influence peer reviewers' evaluations. Such factors may however also be important such as the use of track-records about the veracity of a researchers' prior publications and its alignment with public interests. Nevertheless, evaluation systems – include those of peer-review – may substantially lack mechanisms and criteria that are oriented or well-performingly oriented towards merit, real-world positive impact, progress and public usefulness rather than analytical indicators such as number of citations or altmetrics even when such can be used as partial indicators of such ends. Rethinking of the academic reward structure "to offer more formal recognition for intermediate products, such as data" could have positive impacts and reduce data withholding.
Recognition of training
A commentary noted that academic rankings don't consider where (country and institute) the respective researchers were trained.
Scientometrics
Scientometrics concerns itself with measuring bibliographic data in scientific publications. Major research issues include the measurement of the impact of research papers and academic journals, the understanding of scientific citations, and the use of such measurements in policy and management contexts. Studies suggest that "metrics used to measure academic success, such as the number of publications, citation number, and impact factor, have not changed for decades" and have to some degrees "ceased" to be good measures, leading to issues such as "overproduction, unnecessary fragmentations, overselling, predatory journals (pay and publish), clever plagiarism, and deliberate obfuscation of scientific results so as to sell and oversell".
Novel tools in this area include systems to quantify how much the cited-node informs the citing-node. This can be used to convert unweighted citation networks to a weighted one and then for importance assessment, deriving "impact metrics for the various entities involved, like the publications, authors etc" as well as, among other tools, for search engine- and recommendation systems.
Science governance
Science funding and science governance can also be explored and informed by metascience.
Incentives
Various interventions such as prioritization can be important. For instance, the concept of differential technological development refers to deliberately developing technologies – e.g. control-, safety- and policy-technologies versus risky biotechnologies – at different precautionary paces to decrease risks, mainly global catastrophic risk, by influencing the sequence in which technologies are developed. Relying only on the established form of legislation and incentives to ensure the right outcomes may not be adequate as these may often be too slow or inappropriate.
Other incentives to govern science and related processes, including via metascience-based reforms, may include ensuring accountability to the public (in terms of e.g. accessibility of, especially publicly-funded, research or of it addressing various research topics of public interest in serious manners), increasing the qualified productive scientific workforce, improving the efficiency of science to improve problem-solving in general, and facilitating that unambiguous societal needs based on solid scientific evidence – such as about human physiology – are adequately prioritized and addressed. Such interventions, incentives and intervention-designs can be subjects of metascience.
Science funding and awards
Scientific awards are one category of science incentives. Metascience can explore existing and hypothetical systems of science awards. For instance, it found that work honored by Nobel Prizes clustered in only a few scientific fields with only 36/71 having received at least one Nobel Prize. Of the 114/849 domains science could be divided into their DC2 and DC3 classification systems, five were shown to comprise over half of the Nobel Prizes awarded between 1995 and 2017 (particle physics [14%], cell biology [12.1%], atomic physics [10.9%], neuroscience [10.1%], molecular chemistry [5.3%]).
A study found that delegation of responsibility by policy-makers – a centralized authority-based top-down approach – for knowledge production and appropriate funding to science with science subsequently somehow delivering "reliable and useful knowledge to society" is too simple.
Measurements show that allocation of bio-medical resources can be more strongly correlated to previous allocations and research than to burden of diseases.
A study suggests that "[i]f peer review is maintained as the primary mechanism of arbitration in the competitive selection of research reports and funding, then the scientific community needs to make sure it is not arbitrary".
Studies indicate there to is a need to "reconsider how we measure success" .
Funding data
Funding information from grant databases and funding acknowledgment sections can be sources of data for scientometrics studies, e.g. for investigating or recognition of the impact of funding entities on the development of science and technology.
Research questions and coordination
Risk governance
Science communication and public use
It has been argued that "science has two fundamental attributes that underpin its value as a global public good: that knowledge claims and the evidence on which they are based are made openly available to scrutiny, and that the results of scientific research are communicated promptly and efficiently". Metascientific research is exploring topics of science communication such as media coverage of science, science journalism and online communication of results by science educators and scientists. A study found that the "main incentive academics are offered for using social media is amplification" and that it should be "moving towards an institutional culture that focuses more on how these [or such] platforms can facilitate real engagement with research". Science communication may also involve the communication of societal needs, concerns and requests to scientists.
Alternative metrics tools
Alternative metrics tools can be used not only for help in assessment (performance and impact) and findability, but also aggregate many of the public discussions about a scientific paper in social media such as reddit, citations on Wikipedia, and reports about the study in the news media which can then in turn be analyzed in metascience or provided and used by related tools. In terms of assessment and findability, altmetrics rate publications' performance or impact by the interactions they receive through social media or other online platforms, which can for example be used for sorting recent studies by measured impact, including before other studies are citing them. The specific procedures of established altmetrics are not transparent and the used algorithms can not be customized or altered by the user as open source software can. A study has described various limitations of altmetrics and points "toward avenues for continued research and development". They are also limited in their use as a primary tool for researchers to find received constructive feedback.
Societal implications and applications
It has been suggested that it may benefit science if "intellectual exchange—particularly regarding the societal implications and applications of science and technology—are better appreciated and incentivized in the future".
Knowledge integration
Primary studies "without context, comparison or summary are ultimately of limited value" and various types of research syntheses and summaries integrate primary studies. Progress in key social-ecological challenges of the global environmental agenda is "hampered by a lack of integration and synthesis of existing scientific evidence", with a "fast-increasing volume of data", compartmentalized information and generally unmet evidence synthesis challenges. According to Khalil, researchers are facing the problem of too many papers – e.g. in March 2014 more than 8,000 papers were submitted to arXiv – and to "keep up with the huge amount of literature, researchers use reference manager software, they make summaries and notes, and they rely on review papers to provide an overview of a particular topic". He notes that review papers are usually (only)" for topics in which many papers were written already, and they can get outdated quickly" and suggests "wiki-review papers" that get continuously updated with new studies on a topic and summarize many studies' results and suggest future research. A study suggests that if a scientific publication is being cited in a Wikipedia article this could potentially be considered as an indicator of some form of impact for this publication, for example as this may, over time, indicate that the reference has contributed to a high-level of summary of the given topic.
Science journalism
Science journalists play an important role in the scientific ecosystem and in science communication to the public and need to "know how to use, relevant information when deciding whether to trust a research finding, and whether and how to report on it", vetting the findings that get transmitted to the public.
Science education
Some studies investigate science education, e.g. the teaching about selected scientific controversies and historical discovery process of major scientific conclusions, and common scientific misconceptions. Education can also be a topic more generally such as how to improve the quality of scientific outputs and reduce the time needed before scientific work or how to enlarge and retain various scientific workforces.
Science misconceptions and anti-science attitudes
Many students have misconceptions about what science is and how it works. Anti-science attitudes and beliefs are also a subject of research. Hotez suggests antiscience "has emerged as a dominant and highly lethal force, and one that threatens global security", and that there is a need for "new infrastructure" that mitigates it.
Evolution of sciences
Scientific practice
Metascience can investigate how scientific processes evolve over time. A study found that teams are growing in size, "increasing by an average of 17% per decade".
It was found that prevalent forms of non-open access publication and prices charged for many conventional journals – even for publicly funded papers – are unwarranted, unnecessary – or suboptimal – and detrimental barriers to scientific progress. Open access can save considerable amounts of financial resources, which could be used otherwise, and level the playing field for researchers in developing countries. There are substantial expenses for subscriptions, gaining access to specific studies, and for article processing charges. Paywall: The Business of Scholarship is a documentary on such issues.
Another topic are the established styles of scientific communication (e.g. long text-form studies and reviews) and the scientific publishing practices – there are concerns about a "glacial pace" of conventional publishing. The use of preprint-servers to publish study-drafts early is increasing and open peer review, new tools to screen studies, and improved matching of submitted manuscripts to reviewers are among the proposals to speed up publication.
Science overall and intrafield developments
Studies have various kinds of metadata which can be utilized, complemented and made accessible in useful ways. OpenAlex is a free online index of over 200 million scientific documents that integrates and provides metadata such as sources, citations, author information, scientific fields and research topics. Its API and open source website can be used for metascience, scientometrics and novel tools that query this semantic web of papers. Another project under development, Scholia, uses metadata of scientific publications for various visualizations and aggregation features such as providing a simple user interface summarizing literature about a specific feature of the SARS-CoV-2 virus using Wikidata's "main subject" property.
Subject-level resolutions
Beyond metadata explicitly assigned to studies by humans, natural language processing and AI can be used to assign research publications to topics – one study investigating the impact of science awards used such to associate a paper's text (not just keywords) with the linguistic content of Wikipedia's scientific topics pages ("pages are created and updated by scientists and users through crowdsourcing"), creating meaningful and plausible classifications of high-fidelity scientific topics for further analysis or navigability.
Growth or stagnation of science overall
Metascience research is investigating the growth of science overall, using e.g. data on the number of publications in bibliographic databases. A study found segments with different growth rates appear related to phases of "economic (e.g., industrialization)" – money is considered as necessary input to the science system – "and/or political developments (e.g., Second World War)". It also confirmed a recent exponential growth in the volume of scientific literature and calculated an average doubling period of 17.3 years.
However, others have pointed out that is difficult to measure scientific progress in meaningful ways, partly because it's hard to accurately evaluate how important any given scientific discovery is. A variety of perspectives of the trajectories of science overall (impact, number of major discoveries, etc) have been described in books and articles, including that science is becoming harder (per dollar or hour spent), that if science "slowing today, it is because science has remained too focused on established fields", that papers and patents are increasingly less likely to be "disruptive" in terms of breaking with the past as measured by the "CD index", and that there is a great stagnation – possibly as part of a larger trend – whereby e.g. "things haven't changed nearly as much since the 1970s" when excluding the computer and the Internet.
Better understanding of potential slowdowns according to some measures could be a major opportunity to improve humanity's future. For example, emphasis on citations in the measurement of scientific productivity, information overloads, reliance on a narrower set of existing knowledge (which may include narrow specialization and related contemporary practices) , and risk-avoidant funding structures may have "toward incremental science and away from exploratory projects that are more likely to fail". The study that introduced the "CD index" suggests the overall number of papers has risen while the total of "highly disruptive" papers as measured by the index hasn't (notably, the 1998 discovery of the accelerating expansion of the universe has a CD index of 0). Their results also suggest scientists and inventors "may be struggling to keep up with the pace of knowledge expansion".
Various ways of measuring "novelty" of studies, novelty metrics, have been proposed to balance a potential anti-novelty bias – such as textual analysis or measuring whether it makes first-time-ever combinations of referenced journals, taking into account the difficulty. Other approaches include pro-actively funding risky projects.
Topic mapping
Science maps could show main interrelated topics within a certain scientific domain, their change over time, and their key actors (researchers, institutions, journals). They may help find factors determine the emergence of new scientific fields and the development of interdisciplinary areas and could be relevant for science policy purposes. Theories of scientific change could guide "the exploration and interpretation of visualized intellectual structures and dynamic patterns". The maps can show the intellectual, social or conceptual structure of a research field. Beyond visual maps, expert survey-based studies and similar approaches could identify understudied or neglected societally important areas, topic-level problems (such as stigma or dogma), or potential misprioritizations. Examples of such are studies about policy in relation to public health and the social science of climate change mitigation where it has been estimated that only 0.12% of all funding for climate-related research is spent on such despite the most urgent puzzle at the current juncture being working out how to mitigate climate change, whereas the natural science of climate change is already well established.
There are also studies that map a scientific field or a topic such as the study of the use of research evidence in policy and practice, partly using surveys.
Controversies, current debates and disagreement
Some research is investigating scientific controversy or controversies, and may identify currently ongoing major debates (e.g. open questions), and disagreement between scientists or studies. One study suggests the level of disagreement was highest in the social sciences and humanities (0.61%), followed by biomedical and health sciences (0.41%), life and earth sciences (0.29%); physical sciences and engineering (0.15%), and mathematics and computer science (0.06%). Such research may also show, where the disagreements are, especially if they cluster, including visually such as with cluster diagrams.
Challenges of interpretation of pooled results
Studies about a specific research question or research topic are often reviewed in the form of higher-level overviews in which results from various studies are integrated, compared, critically analyzed and interpreted. Examples of such works are scientific reviews and meta-analyses. These and related practices face various challenges and are a subject of metascience.
Various issues with included or available studies such as, for example, heterogeneity of methods used may lead to faulty conclusions of the meta-analysis.
Knowledge integration and living documents
Various problems require swift integration of new and existing science-based knowledge. Especially setting where there are a large number of loosely related projects and initiatives benefit from a common ground or "commons".
Evidence synthesis can be applied to important and, notably, both relatively urgent and certain global challenges: "climate change, energy transitions, biodiversity loss, antimicrobial resistance, poverty eradication and so on". It was suggested that a better system would keep summaries of research evidence up to date via living systematic reviews – e.g. as living documents. While the number of scientific papers and data (or information and online knowledge) has risen substantially, the number of published academic systematic reviews has risen from "around 6,000 in 2011 to more than 45,000 in 2021". An evidence-based approach is important for progress in science, policy, medical and other practices. For example, meta-analyses can quantify what is known and identify what is not yet known and place "truly innovative and highly interdisciplinary ideas" into the context of established knowledge which may enhance their impact.
Factors of success and progress
It has been hypothesized that a deeper understanding of factors behind successful science could "enhance prospects of science as a whole to more effectively address societal problems".
Novel ideas and disruptive scholarship
Two metascientists reported that "structures fostering disruptive scholarship and focusing attention on novel ideas" could be important as in a growing scientific field citation flows disproportionately consolidate to already well-cited papers, possibly slowing and inhibiting canonical progress. A study concluded that to enhance impact of truly innovative and highly interdisciplinary novel ideas, they should be placed in the context of established knowledge.
Mentorship, partnerships and social factors
Other researchers reported that the most successful – in terms of "likelihood of prizewinning, National Academy of Science (NAS) induction, or superstardom" – protégés studied under mentors who published research for which they were conferred a prize after the protégés' mentorship. Studying original topics rather than these mentors' research-topics was also positively associated with success. Highly productive partnerships are also a topic of research – e.g. "super-ties" of frequent co-authorship of two individuals who can complement skills, likely also the result of other factors such as mutual trust, conviction, commitment and fun.
Study of successful scientists and processes, general skills and activities
The emergence or origin of ideas by successful scientists is also a topic of research, for example reviewing existing ideas on how Mendel made his discoveries, – or more generally, the process of discovery by scientists. Science is a "multifaceted process of appropriation, copying, extending, or combining ideas and inventions" [and other types of knowledge or information], and not an isolated process. There are also few studies investigating scientists' habits, common modes of thinking, reading habits, use of information sources, digital literacy skills, and workflows.
Labor advantage
A study theorized that in many disciplines, larger scientific productivity or success by elite universities can be explained by their larger pool of available funded laborers. The study found that university prestige was only associated with higher productivity for faculty with group members, not for faculty publishing alone or the group members themselves. This is presented as evidence that the outsize productivity of elite researchers is not from a more rigorous selection of talent by top universities, but from labor advantages accrued through greater access to funding and the attraction of prestige to graduate and postdoctoral researchers.
Ultimate impacts
Success in science (as indicated in tenure review processes) is often measured in terms of metrics like citations, not in terms of the eventual or potential impact on lives and society, which awards sometimes do. Problems with such metrics are roughly outlined elsewhere in this article and include that reviews replace citations to primary studies. There are also proposals for changes to the academic incentives systems that increase the recognition of societal impact in the research process.
Progress studies
A proposed field of "Progress Studies" could investigate how scientists (or funders or evaluators of scientists) should be acting, "figuring out interventions" and study progress itself. The field was explicitly proposed in a 2019 essay and described as an applied science that prescribes action.
As and for acceleration of progress
A study suggests that improving the way science is done could accelerate the rate of scientific discovery and its applications which could be useful for finding urgent solutions to humanity's problems, improve humanity's conditions, and enhance understanding of nature. Metascientific studies can seek to identify aspects of science that need improvement, and develop ways to improve them. If science is accepted as the fundamental engine of economic growth and social progress, this could raise "the question of what we – as a society – can do to accelerate science, and to direct science toward solving society's most important problems." However, one of the authors clarified that a one-size-fits-all approach is not thought to be right answer – for example, in funding, DARPA models, curiosity-driven methods, allowing "a single reviewer to champion a project even if his or her peers do not agree", and various other approaches all have their uses. Nevertheless, evaluation of them can help build knowledge of what works or works best.
Reforms
Meta-research identifying flaws in scientific practice has inspired reforms in science. These reforms seek to address and fix problems in scientific practice which lead to low-quality or inefficient research.
A 2015 study lists "fragmented" efforts in meta-research.
Pre-registration
The practice of registering a scientific study before it is conducted is called pre-registration. It arose as a means to address the replication crisis. Pregistration requires the submission of a registered report, which is then accepted for publication or rejected by a journal based on theoretical justification, experimental design, and the proposed statistical analysis. Pre-registration of studies serves to prevent publication bias (e.g. not publishing negative results), reduce data dredging, and increase replicability.
Reporting standards
Studies showing poor consistency and quality of reporting have demonstrated the need for reporting standards and guidelines in science, which has led to the rise of organisations that produce such standards, such as CONSORT (Consolidated Standards of Reporting Trials) and the EQUATOR Network.
The EQUATOR (Enhancing the QUAlity and Transparency Of health Research) Network is an international initiative aimed at promoting transparent and accurate reporting of health research studies to enhance the value and reliability of medical research literature. The EQUATOR Network was established with the goals of raising awareness of the importance of good reporting of research, assisting in the development, dissemination and implementation of reporting guidelines for different types of study designs, monitoring the status of the quality of reporting of research studies in the health sciences literature, and conducting research relating to issues that impact the quality of reporting of health research studies. The Network acts as an "umbrella" organisation, bringing together developers of reporting guidelines, medical journal editors and peer reviewers, research funding bodies, and other key stakeholders with a mutual interest in improving the quality of research publications and research itself.
Applications
Information and communications technologies
Metascience is used in the creation and improvement of technical systems (ICTs) and standards of science evaluation, incentivation, communication, commissioning, funding, regulation, production, management, use and publication. Such can be called "applied metascience" and may seek to explore ways to increase quantity, quality and positive impact of research. One example for such is the development of alternative metrics.
Study screening and feedback
Various websites or tools also identify inappropriate studies and/or enable feedback such as PubPeer, Cochrane's Risk of Bias Tool and RetractionWatch. Medical and academic disputes are as ancient as antiquity and a study calls for research into "constructive and obsessive criticism" and into policies to "help strengthen social media into a vibrant forum for discussion, and not merely an arena for gladiator matches". Feedback to studies can be found via altmetrics which is often integrated at the website of the study – most often as an embedded Altmetrics badge – but may often be incomplete, such as only showing social media discussions that link to the study directly but not those that link to news reports about the study.
Tools used, modified, extended or investigated
Tools may get developed with metaresearch or can be used or investigated by such. Notable examples may include:
Search engines like Google Scholar are used to find studies and the notification service Google Alerts enables notifications for new studies matching specified search terms. Scholarly communication infrastructure includes search databases.
Shadow library Sci-hub is a topic of metascience
Personal knowledge management systems for research-, knowledge- and task management, such as saving information in organized ways with multi-document text editors for future use Such systems could be described as part of, along with e.g. Web browser (tabs-addons etc) and search software, "mind-machine partnerships" that could be investigated by metascience for how they could improve science.
Scholia – efforts to open scholarly publication metadata and use it via Wikidata.
Various software enables common metascientific practices such as bibliometric analysis.
Development
According to a study "a simple way to check how often studies have been repeated, and whether or not the original findings are confirmed" is needed due to reproducibility issues in science. A study suggests a tool for screening studies for early warning signs for research fraud.
Medicine
Clinical research in medicine is often of low quality, and many studies cannot be replicated. An estimated 85% of research funding is wasted. Additionally, the presence of bias affects research quality. The pharmaceutical industry exerts substantial influence on the design and execution of medical research. Conflicts of interest are common among authors of medical literature and among editors of medical journals. While almost all medical journals require their authors to disclose conflicts of interest, editors are not required to do so. Financial conflicts of interest have been linked to higher rates of positive study results. In antidepressant trials, pharmaceutical sponsorship is the best predictor of trial outcome.
Blinding is another focus of meta-research, as error caused by poor blinding is a source of experimental bias. Blinding is not well reported in medical literature, and widespread misunderstanding of the subject has resulted in poor implementation of blinding in clinical trials. Furthermore, failure of blinding is rarely measured or reported. Research showing the failure of blinding in antidepressant trials has led some scientists to argue that antidepressants are no better than placebo. In light of meta-research showing failures of blinding, CONSORT standards recommend that all clinical trials assess and report the quality of blinding.
Studies have shown that systematic reviews of existing research evidence are sub-optimally used in planning a new research or summarizing the results. Cumulative meta-analyses of studies evaluating the effectiveness of medical interventions have shown that many clinical trials could have been avoided if a systematic review of existing evidence was done prior to conducting a new trial. For example, Lau et al. analyzed 33 clinical trials (involving 36974 patients) evaluating the effectiveness of intravenous streptokinase for acute myocardial infarction. Their cumulative meta-analysis demonstrated that 25 of 33 trials could have been avoided if a systematic review was conducted prior to conducting a new trial. In other words, randomizing 34542 patients was potentially unnecessary. One study analyzed 1523 clinical trials included in 227 meta-analyses and concluded that "less than one quarter of relevant prior studies" were cited. They also confirmed earlier findings that most clinical trial reports do not present systematic review to justify the research or summarize the results.
Many treatments used in modern medicine have been proven to be ineffective, or even harmful. A 2007 study by John Ioannidis found that it took an average of ten years for the medical community to stop referencing popular practices after their efficacy was unequivocally disproven.
Psychology
Metascience has revealed significant problems in psychological research. The field suffers from high bias, low reproducibility, and widespread misuse of statistics. The replication crisis affects psychology more strongly than any other field; as many as two-thirds of highly publicized findings may be impossible to replicate. Meta-research finds that 80-95% of psychological studies support their initial hypotheses, which strongly implies the existence of publication bias.
The replication crisis has led to renewed efforts to re-test important findings. In response to concerns about publication bias and p-hacking, more than 140 psychology journals have adopted result-blind peer review, in which studies are pre-registered and published without regard for their outcome. An analysis of these reforms estimated that 61 percent of result-blind studies produce null results, in contrast with 5 to 20 percent in earlier research. This analysis shows that result-blind peer review substantially reduces publication bias.
Psychologists routinely confuse statistical significance with practical importance, enthusiastically reporting great certainty in unimportant facts. Some psychologists have responded with an increased use of effect size statistics, rather than sole reliance on the p values.
Physics
Richard Feynman noted that estimates of physical constants were closer to published values than would be expected by chance. This was believed to be the result of confirmation bias: results that agreed with existing literature were more likely to be believed, and therefore published. Physicists now implement blinding to prevent this kind of bias.
Computer Science
Web measurement studies are essential for understanding the workings of the modern Web, particularly in the fields of security and privacy. However, these studies often require custom-built or modified crawling setups, leading to a plethora of analysis tools for similar tasks. In a paper by Nurullah Demir et al., the authors surveyed 117 recent research papers to derive best practices for Web-based measurement studies and establish criteria for reproducibility and replicability. They found that experimental setups and other critical information for reproducing and replicating results are often missing. In a large-scale Web measurement study on 4.5 million pages with 24 different measurement setups, the authors demonstrated the impact of slight differences in experimental setups on the overall results, emphasizing the need for accurate and comprehensive documentation.
Organizations and institutes
There are several organizations and universities across the globe which work on meta-research – these include the Meta-Research Innovation Center at Berlin, the Meta-Research Innovation Center at Stanford, the Meta-Research Center at Tilburg University, the Meta-research & Evidence Synthesis Unit, The George Institute for Global Health at India and Center for Open Science. Organizations that develop tools for metascience include OurResearch, Center for Scientific Integrity and altmetrics companies. There is an annual Metascience Conference hosted by the Association for Interdisciplinary Meta-Research and Open Science (AIMOS) and biannual conference hosted by the Centre for Open Science.
See also
References
Further reading
Bonett, D.G. (2021). Design and analysis of replication studies. Organizational Research Methods, 24, 513-529. https://doi.org/10.1177/1094428120911088
Lydia Denworth, "A Significant Problem: Standard scientific methods are under fire. Will anything change?", Scientific American, vol. 321, no. 4 (October 2019), pp. 62–67.
"The use of p values for nearly a century [since 1925] to determine statistical significance of experimental results has contributed to an illusion of certainty and [to] reproducibility crises in many scientific fields. There is growing determination to reform statistical analysis... Some [researchers] suggest changing statistical methods, whereas others would do away with a threshold for defining "significant" results." (p. 63.)
External links
Journals
Minerva: A Journal of Science, Learning and Policy
Research Integrity and Peer Review
Research Policy
Science and Public Policy
Conferences
Annual Metascience Conference
Epistemology of science
Ethics and statistics
Evidence-based practices
Metatheory of science
Research
Science policy
Scientific method | Metascience | [
"Technology"
] | 8,348 | [
"Ethics and statistics",
"Ethics of science and technology"
] |
53,149,467 | https://en.wikipedia.org/wiki/Marchetti%20dilatometer%20test | Marchetti dilatometer test or flat dilatometer, is a type of dilatometer commonly designated by DMT.
It was created by Silvano Marchetti (1980) and is one of the most versatile tools for soil characterization, namely loose to medium compacted granular soils and soft to medium clays, or even stiffer if a good reaction system is provided. The main reasons for its usefulness deriving geotechnical parameters are related to the simplicity and the speed of execution, generating continuous data profiles of high accuracy and reproducibility.
References
Measuring instruments
Soil mechanics | Marchetti dilatometer test | [
"Physics",
"Technology",
"Engineering"
] | 120 | [
"Soil mechanics",
"Applied and interdisciplinary physics",
"Measuring instruments"
] |
53,150,080 | https://en.wikipedia.org/wiki/Meta.Numerics | Meta.Numerics is an open-source library for advanced scientific computing on the .NET platform. It provides an object-oriented API supporting advanced functions, matrix algebra, statistics, optimization, and other numerical algorithms.
History
Version 1.0 was released in April 2009. The current version 4.1.4 was released in August 2020. It has been used in academic research and software development. It is listed in the software index of the Digital Library of Mathematical Functions.
References
External links
Meta.Numerics Website
Meta.Numerics Project on GitHub
Meta.Numerics Project on CodePlex
Numerical software
C Sharp libraries
Software using the MS-PL license | Meta.Numerics | [
"Mathematics"
] | 137 | [
"Numerical software",
"Mathematical software"
] |
53,151,479 | https://en.wikipedia.org/wiki/List%20of%20amateur%20radio%20software | This is a list of software for amateur radio.
Software tools
Logging software
Operating systems
The Debian project maintains a pure blend that includes ham radio software. The HamBSD project is a variation of OpenBSD.
See also
Amateur radio station § Computer-control software
List of amateur radio modes
Software-defined radio
References
External links
DXZone Amateur Radio Software - An exhaustive directory of amateur radio software
Software
Software
Lists of software | List of amateur radio software | [
"Technology"
] | 87 | [
"Computing-related lists",
"Lists of software"
] |
53,153,455 | https://en.wikipedia.org/wiki/Maximal%20entropy%20random%20walk | Maximal entropy random walk (MERW) is a popular type of biased random walk on a graph, in which transition probabilities are chosen accordingly to the principle of maximum entropy, which says that the probability distribution which best represents the current state of knowledge is the one with largest entropy. While standard random walk chooses for every vertex uniform probability distribution among its outgoing edges, locally maximizing entropy rate, MERW maximizes it globally (average entropy production) by assuming uniform probability distribution among all paths in a given graph.
MERW is used in various fields of science. A direct application is choosing probabilities to maximize transmission rate through a constrained channel, analogously to Fibonacci coding. Its properties also made it useful for example in analysis of complex networks, like link prediction, community detection,
robust transport over networks and centrality measures. Also in image analysis, for example for detecting visual saliency regions, object localization, tampering detection or tractography problem.
Additionally, it recreates some properties of quantum mechanics, suggesting a way to repair the discrepancy between diffusion models and quantum predictions, like Anderson localization.
Basic model
Consider a graph with vertices, defined by an adjacency matrix : if there is an edge from vertex to , 0 otherwise. For simplicity assume it is an undirected graph, which corresponds to a symmetric ; however, MERW can also be generalized for directed and weighted graphs (for example Boltzmann distribution among paths instead of uniform).
We would like to choose a random walk as a Markov process on this graph: for every vertex and its outgoing edge to , choose probability of the walker randomly using this edge after visiting . Formally, find a stochastic matrix (containing the transition probabilities of a Markov chain) such that
for all and
for all .
Assuming this graph is connected and not periodic, ergodic theory says that evolution of this stochastic process leads to some stationary probability distribution such that .
Using Shannon entropy for every vertex and averaging over probability of visiting this vertex (to be able to use its entropy), we get the following formula for average entropy production (entropy rate) of the stochastic process:
This definition turns out to be equivalent to the asymptotic average entropy (per length) of the probability distribution in the space of paths for this stochastic process.
In the standard random walk, referred to here as generic random walk (GRW), we naturally choose that each outgoing edge is equally probable:
.
For a symmetric it leads to a stationary probability distribution with
.
It locally maximizes entropy production (uncertainty) for every vertex, but usually leads to a suboptimal averaged global entropy rate .
MERW chooses the stochastic matrix which maximizes , or equivalently assumes uniform probability distribution among all paths in a given graph. Its formula is obtained by first calculating the dominant eigenvalue and corresponding eigenvector of the adjacency matrix, i.e. the largest with corresponding such that . Then stochastic matrix and stationary probability distribution are given by
for which every possible path of length from the -th to -th vertex has probability
.
Its entropy rate is and the stationary probability distribution is
.
In contrast to GRW, the MERW transition probabilities generally depend on the structure of the entire graph (are nonlocal). Hence, they should not be imagined as directly applied by the walker – if random-looking decisions are made based on the local situation, like a person would make, the GRW approach is more appropriate. MERW is based on the principle of maximum entropy, making it the safest assumption when we don't have any additional knowledge about the system. For example, it would be appropriate for modelling our knowledge about an object performing some complex dynamics – not necessarily random, like a particle.
Sketch of derivation
Assume for simplicity that the considered graph is indirected, connected and aperiodic, allowing to conclude from the Perron–Frobenius theorem that the dominant eigenvector is unique. Hence can be asymptotically () approximated by (or in bra–ket notation).
MERW requires uniform distribution along paths. The number of paths with length and vertex in the center is
,
hence for all ,
.
Analogously calculating probability distribution for two succeeding vertices, one obtains that the probability of being at the -th vertex and next at the -th vertex is
.
Dividing by the probability of being at the -th vertex, i.e. , gives for the conditional probability of the -th vertex being next after the -th vertex
.
Weighted MERW: Boltzmann path ensemble
We have assumed that for MERW corresponding to uniform ensemble among paths. However, the above derivation works for real nonnegative . Parametrizing and asking for probability of length path , we get:
As in Boltzmann distribution of paths for energy defined as sum of over given path. For example, it allows to calculate probability distribution of patterns in Ising model.
Examples
Let us first look at a simple nontrivial situation: Fibonacci coding, where we want to transmit a message as a sequence of 0s and 1s, but not using two successive 1s: after a 1 there has to be a 0. To maximize the amount of information transmitted in such sequence, we should assume uniform probability distribution in the space of all possible sequences fulfilling this constraint. To practically use such long sequences, after 1 we have to use 0, but there remains a freedom of choosing the probability of 0 after 0. Let us denote this probability by , then entropy coding would allow encoding a message using this chosen probability distribution. The stationary probability distribution of symbols for a given turns out to be . Hence, entropy production is , which is maximized for , known as the golden ratio. In contrast, standard random walk would choose suboptimal . While choosing larger reduces the amount of information produced after 0, it also reduces frequency of 1, after which we cannot write any information.
A more complex example is the defected one-dimensional cyclic lattice: let say 1000 nodes connected in a ring, for which all nodes but the defects have a self-loop (edge to itself). In standard random walk (GRW) the stationary probability distribution would have defect probability being 2/3 of probability of the non-defect vertices – there is nearly no localization, also analogously for standard diffusion, which is infinitesimal limit of GRW. For MERW we have to first find the dominant eigenvector of the adjacency matrix – maximizing in:
for all positions , where for defects, 0 otherwise. Substituting and multiplying the equation by −1 we get:
where is minimized now, becoming the analog of energy. The formula inside the bracket is discrete Laplace operator, making this equation a discrete analogue of stationary Schrodinger equation. As in quantum mechanics, MERW predicts that the probability distribution should lead exactly to the one of quantum ground state: with its strongly localized density (in contrast to standard diffusion). Taking the infinitesimal limit, we can get standard continuous stationary (time-independent) Schrodinger equation ( for ) here.
See also
Principle of maximum entropy
Eigenvector centrality
Markov chain
Anderson localization
References
External links
Gábor Simonyi, Y. Lin, Z. Zhang, "Mean first-passage time for maximal-entropy random walks in complex networks". Scientific Reports, 2014.
Electron Conductance Models Using Maximal Entropy Random Walks Wolfram Demonstration Project
Network theory
Diffusion
Information theory
Quantum mechanics | Maximal entropy random walk | [
"Physics",
"Chemistry",
"Mathematics",
"Technology",
"Engineering"
] | 1,553 | [
"Transport phenomena",
"Physical phenomena",
"Telecommunications engineering",
"Diffusion",
"Applied mathematics",
"Theoretical physics",
"Quantum mechanics",
"Graph theory",
"Network theory",
"Computer science",
"Information theory",
"Mathematical relations"
] |
53,154,601 | https://en.wikipedia.org/wiki/NGC%20416 | NGC 416 is a globular cluster located in the constellation Tucana. It was discovered on September 5, 1826, by James Dunlop. It was described by Dreyer as "faint, pretty small, round, gradually brighter middle". At a distance of about , it is located within the Small Magellanic Cloud. At an aperture of 31 arcseconds, its apparent V-band magnitude is 11.42, but at this wavelength, it has 0.25 magnitudes of interstellar extinction.
NGC 416 is about 6.6 billion years old. Its estimated mass is , and its total luminosity is , leading to a mass-to-luminosity ratio of 0.72 /. All else equal, older star clusters have higher mass-to-luminosity ratios; that is, they have lower luminosities for the same mass.
See also
List of NGC objects (1–1000)
References
External links
0416
18260905
Tucana
Small Magellanic Cloud
Open clusters
Discoveries by James Dunlop | NGC 416 | [
"Astronomy"
] | 214 | [
"Tucana",
"Constellations"
] |
53,154,894 | https://en.wikipedia.org/wiki/Leipzig%20L-IV%20experiment%20accident | The Leipzig L-IV experiment accident was the first nuclear accident in history. It occurred on 23 June 1942 in a laboratory at the Physical Institute of the Leipzig University in Leipzig, Germany. There was a steam explosion and a reactor fire in the "uranium machine", a primitive form of research reactor.
Shortly after the Leipzig L-IV atomic pile—worked on by Werner Heisenberg and Robert Döpel—demonstrated Germany's first signs of neutron propagation, the device was checked for a possible heavy water leak. During the inspection, air leaked in, igniting the uranium powder inside. The burning uranium boiled the water jacket, generating enough steam pressure to blow the reactor apart. Burning uranium powder scattered throughout the lab causing a larger fire at the facility.
This happened after 20 days of operation when Werner Paschen opened the machine at the request of Döpel after blisters formed at the gasket. As glowing uranium powder shot to the 6 meter high ceiling and the apparatus heated up to 1000 degrees, Heisenberg was asked for help but could not provide it.
The experiment
Results from the L-IV trial, in the first half of 1942, indicated that the spherical geometry, with five tonnes of heavy water and 10 tonnes of metallic uranium, could sustain a fission reaction. They had achieved the first net neutron production of the German program, three years after the first such pile in history by Hans von Halban and colleagues in Paris. The results were set forth in an article by Robert Döpel, Klara Döpel and W. Heisenberg. The article was published at first in the Kernphysikalische Forschungsberichte (Research Reports in Nuclear Physics), a classified internal reporting vehicle of the Uranverein.
The Leipzig research group was led by Heisenberg until 1942 who in winter 1939/1940 reported on the possibilities and feasibility of energy extraction from uranium for a uranium reactor and nuclear bomb. After the report Heisenberg withdrew from practical experiments and left the execution of the experiments L-I, L-II, L-III and L-IV mostly up to his coworkers. The accident ended the Leipzig uranium projects.
See also
German nuclear weapons program
Nuclear safety and security
Nuclear power in Germany
Lists of nuclear disasters and radioactive incidents
References
Nuclear accidents and incidents
Nuclear program of Nazi Germany
1942 in Germany
1942 disasters in Germany
Leipzig in World War II
Leipzig University | Leipzig L-IV experiment accident | [
"Chemistry"
] | 486 | [
"Nuclear accidents and incidents",
"Radioactivity"
] |
53,154,952 | https://en.wikipedia.org/wiki/Angiopoietin-like%20proteins | The Angiopoietin-like proteins are proteins structurally like the angiopoietins but which do not bind to the angiopoietin receptors.
Also known as the Angiopoietin-related proteins.
Members
Angiopoietin-related protein 1, gene ANGPTL1
Angiopoietin-related protein 2, gene ANGPTL2
Angiopoietin-related protein 3, gene ANGPTL3
Angiopoietin-related protein 4, gene ANGPTL4
Angiopoietin-related protein 5, gene ANGPTL5, mainly expressed in adult human heart.
Angiopoietin-related protein 6, gene ANGPTL6, associations with components of metabolic syndrome.
Angiopoietin-related protein 7, gene ANGPTL7
Angiopoietin-related protein 8, gene ANGPTL8, also known as lipasin because of its capacity in LPL inhibition.
References
Human proteins | Angiopoietin-like proteins | [
"Chemistry"
] | 205 | [
"Biochemistry stubs",
"Protein stubs"
] |
53,155,253 | https://en.wikipedia.org/wiki/OpenKeychain | OpenKeychain is a free and open-source mobile app for the Android operating system that provides strong, user-based encryption which is compatible with the OpenPGP standard. This allows users to encrypt, decrypt, sign, and verify signatures for text, emails, and files. The app allows the user to store the public keys of other users with whom they interact, and to encrypt files such that only a specified user can decrypt them. In the same manner, if a file is received from another user and its public keys are saved, the receiver can verify the authenticity of that file and decrypt it if necessary. As of August 2021, it is no longer actively developed.
K-9 Mail Support
Together with K-9 Mail, it supports end-to-end encrypted emails via the OpenPGP INLINE and PGP/MIME formats. The developers of OpenKeychain and K-9 Mail are trying to change the way user interfaces for email encryption are designed. They propose to remove the ability to create encrypted-only emails and hide the case of signed-only emails. Instead, they focus on end-to-end security that provides confidentiality and authenticity by always encrypting and signing emails together.
Reception
OpenKeychain is listed on the official OpenPGP homepage and the well-known developer collective Guardian Project recommends it instead of APG to encrypt emails. TechRepublic published an article about it and conclude that "OpenKeychain happens to be one of the easiest encryption tools available for Android (that also happens to best follow OpenPGP standards)." The publisher Heise reviewed it in their c't Android magazine 2016 and discussed OpenKeychain's backup mechanism. The academic community uses OpenKeychain for experimental evaluations: It has been used as an example where cryptographic operations could be executed in a Trusted Execution Environment. Furthermore, modern alternatives for public key fingerprints have been implemented by other researchers. In 2016, the German Federal Office for Information Security published a study about OpenPGP on Android and evaluated OpenKeychain's functionality. OpenKeychain has been adapted to work with smartcards and NFC rings resulting in a usability study published on Ubicomp 2017.
Funding
The OpenKeychain developers participated in 3 Google Summer of Code programs with a total of 6 successful students. In 2015, one of the main developers got a one-year funding to improve the OpenPGP support in K-9 Mail paid by the Open Technology Fund.
History
OpenKeychain has been created as a fork of Android Privacy Guard (APG) in March 2012. Between December 2010 and October 2013 no new version of APG was released. Thus, OpenKeychain has been started with the intention of picking up the development to improve the user interface and API. A first version 2.0 has been released in January 2013. After three years without updates, APG merged back security fixes from OpenKeychain and some months later rebased an entire new version on OpenKeychain’s source code. However, this process stopped in March 2014, while the OpenKeychain developers continued to regularly release new versions. A number of vulnerabilities found by Cure53 have been fixed in OpenKeychain. These are still not fixed in APG since its last release in March 2014. Since K-9 Mail version 5.200, APG is no longer supported as a cryptography provider.
References
External links
GitHub repository of OpenKeychain
Free and open-source Android software
OpenPGP
Cryptographic software | OpenKeychain | [
"Mathematics"
] | 755 | [
"Cryptographic software",
"Mathematical software"
] |
53,155,398 | https://en.wikipedia.org/wiki/List%20of%20scattering%20experiments | This is a list of scattering experiments.
Specific experiments of historical significance
Davisson–Germer experiment
Gold foil experiments, performed by Geiger and Marsden for Rutherford which discovered the atomic nucleus
Elucidation of the structure of DNA by X-ray crystallography
Discovery of the antiproton at the Bevatron
Discovery of W and Z bosons at CERN
Discovery of the Higgs boson at the Large Hadron Collider
MINERνA
Types of experiment
Optical methods
Compton scattering
Raman scattering
X-ray crystallography
Biological small-angle scattering with X-rays, or Small-angle X-ray scattering
Static light scattering
Dynamic light scattering
Polymer scattering with X-rays
Neutron-based methods
Neutron scattering
Biological small-angle scattering with neutrons, or Small-angle neutron scattering
Polymer scattering with neutrons
Particle accelerators
Electrostatic nuclear accelerator
Linear induction accelerator
Betatron
Linear particle accelerator
Cyclotron
Synchrotron
Physics-related lists
Physics experiments
Chemistry-related lists
Biology-related lists | List of scattering experiments | [
"Physics",
"Chemistry"
] | 203 | [
"Experimental physics",
"Physics experiments",
"nan"
] |
53,155,558 | https://en.wikipedia.org/wiki/Dietz%20Computer%20Systems | Dietz Computer Systems was a German minicomputer manufacturer with its main office in Mülheim an der Ruhr, Germany.
The systems were used for industrial and business data processing, as well as for technical and scientific purposes. A popular computer-aided design software, Technovision, ran on the systems produced by Dietz.
References
Companies based in North Rhine-Westphalia
Defunct computer companies of Germany | Dietz Computer Systems | [
"Technology"
] | 82 | [
"Computing stubs",
"Computer company stubs"
] |
53,156,368 | https://en.wikipedia.org/wiki/Beijing%E2%80%93Washington%20hotline | The Beijing–Washington hotline is a system that allows direct communication between the leaders of the United States and China. This hotline was established in November 2007, when both countries announced that they would set up a military hotline to avoid misunderstanding between their militaries during any moments of crisis in the Pacific.
History
Discussions to set up a Beijing–Washington hotline started during a meeting between Chinese president Hu Jintao and U.S. President George W. Bush in April 2006.
On 5 November 2007, U.S. Defense Secretary Robert M. Gates told reporters that he and Chinese Defense Minister Cao Gangchuan formally agreed to set up the dedicated 24-hour phone line in Beijing. According to a report, China's Defense Ministry long resisted the idea of a direct line until June 2007, when General Zhang Qinsheng stated that China was ready to proceed with the establishment at the Shangri-La Dialogue security conference in Singapore. After a meeting in February 2008, China and the United States officially signed an agreement to set up a military hotline between the United States Department of Defense and the Ministry of National Defense of the People's Republic of China. The hotline was set up on 10 April 2008.
The Beijing–Washington hotline uses different procedures compared to the Moscow–Washington hotline which was set up after the Cuban Missile Crisis. The 2008 agreement with China arranges a call to be put through to the Zhongnanhai telecommunications directorate, which has discretion on whether to forward the call to the foreign affairs section of the Department of Defense or the PLA's command headquarters in West Beijing. Furthermore, in protest against US actions, the Chinese have cut off the hotline twice for extended time periods.
In September 2015, Chinese leader Xi Jinping and U.S. President Barack Obama announced agreements on a new military hotline to reduce the risks of accidental escalations between the two countries.
In May 2021, Kurt Campbell, the US policy coordinator for the Indo-Pacific, said that China had been reluctant to use the hotline, describing it as "the couple of times we've used it, just rung in an empty room for hours upon hours".
In February 2023 Minister of Defense of China, Wei Fenghe, declined to respond to a call from U.S. Defense Secretary Lloyd Austin regarding a balloon over the Beaufort Sea in the vicinity of Deadhorse, Alaska, during the 2023 Chinese balloon incident. The hotline was restored after President Biden's meeting with Xi Jinping at the 2023 APEC summit.
Space hotline
In November 2015, the U.S. and China set up a so-called space hotline, allowing both nations to easily share information about activities in space and help their space and military agencies to discuss "potential collisions, approaches, or tests" to prevent misunderstanding or miscommunication from escalating to a dangerous situation. According to U.S. Assistant Secretary Of State Frank Rose, an urgent safety mechanism was required due to the growing amount of potentially lethal space debris in orbit, as well as numerous undisclosed military satellite launches. The link was established amid tensions due to China ramping up tests of weapons designed to target the orbital networks upon which almost all US high-tech military capabilities depend.
Cyber hotline
In November 2011, an editorial in the China Daily called for closer communication through a cyber red phone, especially in cases of an emergency concerning matters of cyberwarfare.
See also
Moscow–Washington hotline
Seoul–Pyongyang hotline
Islamabad–New Delhi hotline
China–United States relations
References
Communication circuits
China–United States relations
Military communications of the United States
Military communications of China
Hotlines between countries | Beijing–Washington hotline | [
"Engineering"
] | 749 | [
"Telecommunications engineering",
"Communication circuits"
] |
47,497,328 | https://en.wikipedia.org/wiki/Radionuclide%20identification%20device | A radionuclide identification device (RID or RIID) is a small, lightweight, portable gamma-ray spectrometer used for the detection and identification of radioactive substances. As RIIDs are portable, they are suitable for medical and industrial applications, fieldwork, geological surveys, first-line responders in Homeland Security, and Environmental Monitoring and Radiological Mapping along with other industries that necessitate the identification of radioactive substances..
ANSI requirements
RIIDs are designed to meet the requirements set out in IEEE/ANSI N42.34. These standards include water and shock resistance, large gamma energy range, detection of gamma and neutron sources, automatic system calibration, and temperature stabilization. These instruments are equipped with a specific ANSI library that contains a list of standard isotopes. Furthermore, most RIIDs have both a medical and an industrial library. Custom libraries may be included to cater to specific applications required by certain users.
Detectors
Most RIIDs use scintillation detectors of various types and sizes. The most common type of detector is sodium iodide activated with thallium. Other detector types with improved resolution, low background, and thermal neutron detection are readily available. The relative efficiency of germanium detectors (including other types of detectors) are frequently compared to a standard 3 × 3 sodium iodide detector, representing 100% relative efficiency. Various measurements have shown that cerium bromide (CeBr3) has improved efficiency and resolution compared to sodium iodide, with comparably low background radiation.
History
The discovery of the neutron by James Chadwick in 1932 helped to establish the essential nature of the atomic nucleus. Detection of the neutron requires a special environment because neutrons do not typically cause ionization, since they are not charged particles. However, if the interaction of the neutron is with a nuclide of high neutron cross-section, then a response to neutrons becomes probable. Nuclides commonly used as neutron detector materials are helium-3, lithium-6, boron-10 and uranium-235. The detector material is surrounded by a moderator which reduces the kinetic energy of the neutron (slowing down the neutron). Moderated neutrons are commonly called thermal neutrons, and they provide a high probability of interaction with the target material.
The following neutron detectors are among the most common types used today:
Helium-3 gas-filled proportional detectors
3He was first proposed as a neutron detector in 1939. It was first thought to be a radioactive isotope until samples of natural helium were found (which is mostly helium-4). Helium is found just below the Earth's crust in a ratio of 300 atoms of 3He per million atoms of 4He.
With no electrical charge, neutron interaction with atomic electrons is not possible (as in X-ray, gamma, electron or beta detectors). Therefore, we rely on interaction with an atomic nucleus.
The n + 3 He reaction is shown below with conservation of energy as:
n + 3He → 3H + p + 764 keV
The energy of 764 keV is the sum of the proton kinetic energy of 573 keV plus the triton (tritium ion) kinetic energy of 191 keV. This energy (charge) is collected as daughter products, yielding an output pulse that is proportional to the 764 keV energy for thermal neutrons. 3He provides an efficient neutron detector when it reacts by absorbing thermal neutrons, producing a 1H proton and a 3H ion (tritium). Its sensitivity to gamma rays is negligible, providing a very useful neutron detector. Unfortunately, the supply of 3He is limited to production as a byproduct from the decay of tritium (which has a 12.3-year half-life). Tritium is produced either as part of weapons programs as a booster for nuclear weapons or as a byproduct of reactor operation. Therefore, the price of these detectors is somewhat high due to limited availability.
Lithium-6 neutron detectors
Scintillating 6Li glass for neutron detection was first reported in 1957. However, it was not until the early 1990s that major advances were made by Pacific Northwest National Laboratory. These new techniques were first classified and later declassified in 1994.
The scintillating glass fibers operate by combining 6Li and Cerium ions into the glass composition. Since 6Li has a high cross-section for thermal neutron absorption, this reaction will produce a tritium ion, an alpha particle, and kinetic energy. The ionization produced is transferred to the cerium ions which results in an emission of photons with wavelength 390 to 600 nm. This event results in a flash of light of several thousand photons for each neutron absorbed. The glass fiber acts as a waveguide for the scintillation light which is coupled to a PMT. Pulse shape discrimination (PSD) is then used to separate gamma and neutron events.
A similar reaction with 6Li is used for neutron detection in CLYC detectors. The CLYC crystal uses 95% enriched 6Li and is doped with cerium ions. This detector produces monoenergetic pulses above 3 MeV for thermal neutrons. This gamma/neutron separation is further enhanced by PSD and algorithm improvements. Other detectors like CLLBC are available and offer good gamma resolution and neutron separation up to gamma fields of 20 mR/h and higher. Some detectors offer fast timing (~60 ns) so that a large dynamic range in counting rates is possible.
Isotope identification
Gamma rays were first discovered and studied in 1900 by a French chemist, Paul Villard while observing radiation from radium. However, the first quantitative analysis of gamma radiation is credited to Rutherford and Andrade in 1914. This earliest technique was accomplished by diffraction spectroscopy using a rock-salt crystal.
Crystal diffraction is regarded as an important and pioneering effort in the analysis of gamma-ray energy but falls short of a means to accurately quantify and identify various radionuclides. Gamma spectroscopy did not come around for several more decades.
Gamma-ray spectroscopy
A spectrometer system for radionuclide analysis is composed of a photon detector and associated electronics (e.g., amplifier and pulse shaping) including a means of sorting various energy events and recording/displaying the data. These events are sorted to produce a spectrum (histogram) displaying the intensity (of events) as a function of photon energy.
The advent of the sodium-iodide scintillator in 1948 and other detectors to follow became useful for spectroscopy. The photon detector and the Multichannel Pulse-Height Analyzer (MCA) become the primary tools needed to produce a pulse-height spectrum of one or more radionuclides. It is first necessary to derive a digital number that is proportional to the amplitude of the analog pulse. This is performed in an Analog-to-Digital Converter (ADC) which is a key part of the MCA. Several linear and fast ADCs have been developed over the years (e.g., Wilkinson). One of the first MCAs was developed by Fred Goulding in the 1950s, at the Atomic Energy of Canada, Chalk River facility. This MCA was called a “Kicksorter” and boasted excellent linearity and 100 channels. Goulding later worked at the Lawrence Berkeley Lab (1959) and brought some of the early nuclear counting technology to Berkeley and Livermore Labs. Through later years several advances in MCAs have been impressive with 16K channel analyzers being common. Improvements in nuclear detectors have brought improved energy resolution creating advancements in nuclear science. In the early 1960s germanium (Ge) detectors were being developed with excellent energy resolution. This work has continued with an emphasis on high purity and larger ingots. Since these detectors are cooled to liquid nitrogen temperatures advancements in room temperature detectors have been necessary for small, portable instruments called Radioisotope Identification Devices (RIIDs). Newer high-resolution scintillators have improved the functionality of RIIDs as tools for Homeland Security and many other applications requiring the spectroscopic identification of radioisotopes.
Berkeley Nucleonic Corporation (BNC) has been a leader in providing RIIDs for two decades. BNC has implemented several techniques to enhance the accuracy, speed, and sensitivity needed to quickly identify radioisotopes. One of these techniques is called Quadratic Compression Conversion (QCC). QCC is a digital conversion transform used to obtain excellent characterization of spectral peaks. This allows sensitivity beyond conventional spectroscopy by spreading out tightly spaced low-energy peaks and enhancing high-energy peaks for faster and easier search of energy lines across the spectrum. This is especially important for quick indication of highly enriched weapons-grade material. QCC is now incorporated in our new SAM 940+ RIID. This lightweight, hand-held RIID uses some of the newest high-resolution detectors and the capability of auto updates of new software.
Additional features
Some RIIDs have additional features not required by ANSI, such as external probes for verification of Special Nuclear Material (SNM). One example is an external Pancake probe used in the detection of alpha and beta radiation.
References
IEC 62327:2006 – Radiation protection instrumentation – Hand-held instruments for the detection and identification of radionuclides and for the indication of ambient dose equivalent rate from photon radiation.
R. Arlt et al., Semi-empirical approach for performance evaluation of radionuclide identifiers, Nuclear Science Symposium Conference Record (NSS/MIC), 2009 IEEE
External links
US NRC short description of RIDs/RIIDs
Ionising radiation detectors | Radionuclide identification device | [
"Technology",
"Engineering"
] | 1,953 | [
"Ionising radiation detectors",
"Radioactive contamination",
"Measuring instruments"
] |
47,498,197 | https://en.wikipedia.org/wiki/Rubus%20florulentus | Rubus florulentus is a rare Caribbean species of flowering plant in the rose family. It has been found only in Puerto Rico.
The genetics of Rubus is extremely complex, so that it is difficult to decide on which groups should be recognized as species. There are many rare species with limited ranges such as this. Further study is suggested to clarify the taxonomy.
References
florulentus
Plants described in 1890
Endemic flora of Puerto Rico
Flora without expected TNC conservation status | Rubus florulentus | [
"Biology"
] | 97 | [
"Biological hypotheses",
"Controversial taxa",
"Unplaced names"
] |
47,498,291 | https://en.wikipedia.org/wiki/Samsung%20Galaxy%20A8%20%282015%29 | The Samsung Galaxy A8 (stylized as Samsung GALAXY A8) is an Android phablet produced by Samsung Electronics. It was introduced on July 15, 2015.
Specifications
The Galaxy A8 is thinner than earlier models from the A-series lineup, measuring in thickness. The display is protected by Gorilla Glass 4.
Other specifications include a 5.7 inch 1080p (1080x1920) Super AMOLED display, touch based fingerprint sensor integrated to the home button, 16 MP back camera and 5 MP front camera.
It is powered by Exynos 5430, Exynos 5433 or Snapdragon 615. All of these SoCs feature an octa core processor and they are backed by 2 GB RAM and 32 GB internal storage. There is a hybrid SIM slot that can also be used as a microSD card slot. It has a 3050 mAh non-removable battery.
It is shipped with Android 5.1.1 Lollipop.
The Japan KDDI variant includes Oneseg & full Seg TV features while the Korean SK Telecom Variant has a T-DMB feature.
References
Android (operating system) devices
Mobile phones introduced in 2015
Samsung smartphones
Samsung Galaxy
Discontinued Samsung Galaxy smartphones | Samsung Galaxy A8 (2015) | [
"Technology"
] | 253 | [
"Crossover devices",
"Phablets"
] |
47,498,470 | https://en.wikipedia.org/wiki/Hydration%20number | The hydration number of a compound is defined as the number of molecules of water bonded to a central ion, often a metal cation. The hydration number is related to the broader concept of solvation number, the number of solvent molecules bonded to a central atom. The hydration number varies with the atom or ion of interest.
In aqueous solution, solutes interact with water molecules to varying degrees. Metal cations form aquo complexes, wherein the oxygen of water bind to the cation. This first coordination sphere is encased in further solvation shells, whereby water bonds to the coordinated water via hydrogen bonding. For charged species, the orientation of water molecules around the solute dependent on its radius and charge, with cations attracting water’s electronegative oxygen and anions attracting the hydrogens. Uncharged compounds such as methane can also be solvated by water and also have a hydration number. Although solvation shells can contain inner and outer shell solvent-solute interactions, the hydration number generally focuses on the inner shell solvent molecules that directly interact with the solute. Sodium ions
are typically surrounded by 4 to 6 water molecules in their primary hydration shell. This arrangement reflects the ion's charge density and size, leading to strong ion-dipole interactions with water molecules. In contrast, chloride ions generally have a hydration number closer to 6 due to their larger ionic radius and more distributed charge, which allows them to stabilize a larger number of water molecules in their hydration shell.
These hydration characteristics result from the dynamic nature of hydration shells, where water molecules frequently exchange positions between the inner and outer layers, influenced by the strength of ion-water interactions and water-water hydrogen bonding. This behavior has been observed through experimental studies and molecular dynamics simulations.
A variety of definitions exist for hydration number. One such approach counts the number of water molecules bound to the compound more strongly (by 13.3 kcal/mol or more) than they are bound to other water molecules. Hydration number estimates are not limited to integer values (for instance, estimates for sodium include 4, 4.6, 5.3, 5.5, 5.6, 6, 6.5, and 8), with some of the spread of estimated values being due to differing detection methods.
Determination of hydration number
Hydration numbers can be determined by a variety of experimental methods. These include Raman spectroscopy, neutron and X-ray scattering, luminescence, and NMR. Hydration numbers can change depending on whether the species is locked into a crystall or in solution. The apparent hydration number of a species can vary depending on which experimental method was used. The hydration number of large alkali metal cations are difficult to characterize.
Using NMR methods
NMR is the most informative technique for determining hydration numbers in solution. 1H and 17O NMR signals, even for paramagnetic species, can be interpreted to give information on hydration number. Aside from paramagnetism, another complication with NMR is the rate of exchange between bound and unbound water. The second coordination sphere is another aspect to be considered. Finally, ion pairing where the anion enters the solvation shell of the cation must be assessed.
X-ray crystallography
X-ray crystallography provides definitive information on hydration numbers, especially for cations. Most salts crystallize from water with aquo ligands bonded to the cation. Typical hydration numbers are six for first row transition metal ions and nine for lanthanides. Anions compete with aquo ligands for coordination to the cation. A major question concerns the relationship between structure of such hydrates in the crystal and in aqueous solution. X-ray crystallography provides little insight about the hydration numbers for anions and monocations, much less neutral solutes. In such cases, water is bonded so weakly that crystallization is a major perturbation on stoichiometry.
Using Ion movement methods
Ion movement methods involve assessing the resistance to motion hence estimating an effective volume for a solvated ion and from that volume the solvation number. The motion may be from diffusion, mechanically engineered by changes to viscosity or caused by electrical means. Many of these methods give the sum of anion and cation contributions but some can work out values for independent ions. For monoatomic ions, decreasing ionic radius shows decreasing conductivity suggesting that the effective radius of the hydrated ion increases as ionic radius decreases (larger ions are less mobile so their ability to move charge is decreased). Once the mobility of the ions is determined it is possible to estimate diffusion coefficients and from those hydrodynamic radii. The hydrodynamic radii may be used to calculate the number of solvent molecules.
Other hydrates
Even nonpolar entities hydrate and thus can in principle be assigned hydration numbers. For example even methane () forms a hydrate called methane clathrate, which are stable under pressure.
References
Solutions
Chemical properties
Chemical bonding | Hydration number | [
"Physics",
"Chemistry",
"Materials_science"
] | 1,047 | [
"Homogeneous chemical mixtures",
"Condensed matter physics",
"nan",
"Solutions",
"Chemical bonding"
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47,498,670 | https://en.wikipedia.org/wiki/Homotopy%20Lie%20algebra | In mathematics, in particular abstract algebra and topology, a homotopy Lie algebra (or -algebra) is a generalisation of the concept of a differential graded Lie algebra. To be a little more specific, the Jacobi identity only holds up to homotopy. Therefore, a differential graded Lie algebra can be seen as a homotopy Lie algebra where the Jacobi identity holds on the nose. These homotopy algebras are useful in classifying deformation problems over characteristic 0 in deformation theory because deformation functors are classified by quasi-isomorphism classes of -algebras. This was later extended to all characteristics by Jonathan Pridham.
Homotopy Lie algebras have applications within mathematics and mathematical physics; they are linked, for instance, to the Batalin–Vilkovisky formalism much like differential graded Lie algebras are.
Definition
There exists several different definitions of a homotopy Lie algebra, some particularly suited to certain situations more than others. The most traditional definition is via symmetric multi-linear maps, but there also exists a more succinct geometric definition using the language of formal geometry. Here the blanket assumption that the underlying field is of characteristic zero is made.
Geometric definition
A homotopy Lie algebra on a graded vector space is a continuous derivation, , of order that squares to zero on the formal manifold . Here is the completed symmetric algebra, is the suspension of a graded vector space, and denotes the linear dual. Typically one describes as the homotopy Lie algebra and with the differential as its representing commutative differential graded algebra.
Using this definition of a homotopy Lie algebra, one defines a morphism of homotopy Lie algebras, , as a morphism of their representing commutative differential graded algebras that commutes with the vector field, i.e., . Homotopy Lie algebras and their morphisms define a category.
Definition via multi-linear maps
The more traditional definition of a homotopy Lie algebra is through an infinite collection of symmetric multi-linear maps that is sometimes referred to as the definition via higher brackets. It should be stated that the two definitions are equivalent.
A homotopy Lie algebra on a graded vector space is a collection of symmetric multi-linear maps of degree , sometimes called the -ary bracket, for each . Moreover, the maps satisfy the generalised Jacobi identity:
for each n. Here the inner sum runs over -unshuffles and is the signature of the permutation. The above formula have meaningful interpretations for low values of ; for instance, when it is saying that squares to zero (i.e., it is a differential on ), when it is saying that is a derivation of , and when it is saying that satisfies the Jacobi identity up to an exact term of (i.e., it holds up to homotopy). Notice that when the higher brackets for vanish, the definition of a differential graded Lie algebra on is recovered.
Using the approach via multi-linear maps, a morphism of homotopy Lie algebras can be defined by a collection of symmetric multi-linear maps which satisfy certain conditions.
Definition via operads
There also exists a more abstract definition of a homotopy algebra using the theory of operads: that is, a homotopy Lie algebra is an algebra over an operad in the category of chain complexes over the operad.
(Quasi) isomorphisms and minimal models
A morphism of homotopy Lie algebras is said to be a (quasi) isomorphism if its linear component is a (quasi) isomorphism, where the differentials of and are just the linear components of and .
An important special class of homotopy Lie algebras are the so-called minimal homotopy Lie algebras, which are characterized by the vanishing of their linear component . This means that any quasi isomorphism of minimal homotopy Lie algebras must be an isomorphism. Any homotopy Lie algebra is quasi-isomorphic to a minimal one, which must be unique up to isomorphism and it is therefore called its minimal model.
Examples
Because -algebras have such a complex structure describing even simple cases can be a non-trivial task in most cases. Fortunately, there are the simple cases coming from differential graded Lie algebras and cases coming from finite dimensional examples.
Differential graded Lie algebras
One of the approachable classes of examples of -algebras come from the embedding of differential graded Lie algebras into the category of -algebras. This can be described by giving the derivation, the Lie algebra structure, and for the rest of the maps.
Two term L∞ algebras
In degrees 0 and 1
One notable class of examples are -algebras which only have two nonzero underlying vector spaces . Then, cranking out the definition for -algebras this means there is a linear map
,
bilinear maps
, where ,
and a trilinear map
which satisfy a host of identities. pg 28 In particular, the map on implies it has a lie algebra structure up to a homotopy. This is given by the differential of since the gives the -algebra structure implies
,
showing it is a higher Lie bracket. In fact, some authors write the maps as , so the previous equation could be read as
,
showing that the differential of the 3-bracket gives the failure for the 2-bracket to be a Lie algebra structure. It is only a Lie algebra up to homotopy. If we took the complex then has a structure of a Lie algebra from the induced map of .
In degrees 0 and n
In this case, for , there is no differential, so is a Lie algebra on the nose, but, there is the extra data of a vector space in degree and a higher bracket
It turns out this higher bracket is in fact a higher cocyle in Lie algebra cohomology. More specifically, if we rewrite as the Lie algebra and and a Lie algebra representation (given by structure map ), then there is a bijection of quadruples
where is an -cocycle
and the two-term -algebras with non-zero vector spaces in degrees and .pg 42 Note this situation is highly analogous to the relation between group cohomology and the structure of n-groups with two non-trivial homotopy groups. For the case of term term -algebras in degrees and there is a similar relation between Lie algebra cocycles and such higher brackets. Upon first inspection, it's not an obvious results, but it becomes clear after looking at the homology complex
,
so the differential becomes trivial. This gives an equivalent -algebra which can then be analyzed as before.
Example in degrees 0 and 1
One simple example of a Lie-2 algebra is given by the -algebra with where is the cross-product of vectors and is the trivial representation. Then, there is a higher bracket given by the dot product of vectors
It can be checked the differential of this -algebra is always zero using basic linear algebrapg 45.
Finite dimensional example
Coming up with simple examples for the sake of studying the nature of -algebras is a complex problem. For example, given a graded vector space where has basis given by the vector and has the basis given by the vectors , there is an -algebra structure given by the following rules
where . Note that the first few constants are
Since should be of degree , the axioms imply that . There are other similar examples for super Lie algebras. Furthermore, structures on graded vector spaces whose underlying vector space is two dimensional have been completely classified.
See also
Homotopy associative algebra
Differential graded algebra
BV formalism
Simplicial Lie algebra
Hochschild homology
Deformation quantization
Lie n-algebra
References
Introduction
Deformation Theory (lecture notes) - gives an excellent overview of homotopy Lie algebras and their relation to deformation theory and deformation quantization
In physics
— Towards classification of perturbative gauge invariant classical fields.
In deformation and string theory
Related ideas
(Lie algebras in the derived category of coherent sheaves.)
External links
Discusses deformation theory in the context of -algebras.
Homotopical algebra
Differential algebra
Lie algebras | Homotopy Lie algebra | [
"Mathematics"
] | 1,675 | [
"Differential algebra",
"Fields of abstract algebra"
] |
47,498,939 | https://en.wikipedia.org/wiki/Letitia%20Obeng | Letitia Eva Takyibea Obeng (10 January 1925 – 23 March 2023) was the first Ghanaian woman to obtain a degree in zoology and the first to be awarded a doctorate. She is described as "the grandmother of female scientists in Ghana".
Early life and education
Letitia Obeng was born at Anum in the Eastern Region on 10 January 1925. She attended a primary school in Abetifi, Kwahu and a middle school in Kyebi. Between 1939 and 1946, she had her secondary school education at Achimota College. While at school she took the London University International Examination to continue her education, courtesy of a government scholarship at the University of Birmingham (1948–1952), where she was the only African female student on the Edgbaston campus. She graduated from the university with a degree in Zoology. In her autobiography, she describes her experience of coming to study in the United Kingdom in the post-war years, including the prejudices she faced.
Career, achievements and awards
Degrees
Letitia Obeng was the first Ghanaian woman to be awarded a Bachelor of Science degree in Zoology and Botany (1952), a Master of Science degree in Parasitology (1962) and a PhD in Tropical Medicine (1964). Her Bachelor and Master of Science degrees were both awarded by the University of Birmingham and her PhD was awarded by the Liverpool School of Tropical Medicine, where she studied the black fly and its relevance to river blindness. She became very familiar with the freshwater courses in North Wales during her PhD studies and often brought her three children, who were 8, 6 and 3 at the time, to take samples in the area's rivers and streams.
Positions
After her university education in the United Kingdom, she returned to her homeland Ghana and lectured at the University College of Science and Technology now known as the Kwame Nkrumah University of Science and Technology between 1952 and 1959. In 1952, Letitia Obeng became the first female scientist at the Kwame Nkrumah University of Science and Technology (KNUST) where her husband also worked as a lecturer. After her husband's death in 1959, Letitia Obeng moved to the Council for Scientific and Industrial Research (CSIR) (formerly known as National Research Council of Ghana) and in 1964, she established the Institute of Aquatic Biology within the same institution for research on Ghana's huge manmade Volta Lake and its inland water system. Letitia Obeng was the first scientist to be employed by the National Research Council of Ghana. In 1965, Letitia Obeng became a fellow of the Ghana Academy of Arts and Sciences and in 2006, she became the academy's first female president. In 1972, Dr. Obeng delivered the Caroline Haslett Memorial Lecture to the Royal Society for the Encouragement of Arts, Manufactures and Commerce. Her lecture was titled “Nation Building and the African Woman”. Also in 1972, she was an invited participant in the United Nations Human Environment Conference in Stockholm. In 1974, she began work as the Officer in the United Nations Environment Programme (UNEP). In 1980, she became the Director of the UNEP Regional Office for Africa and UNEP's Representative to Africa. Elected the first woman to the Fellowship of the Ghana Academy of Arts and Sciences, in 2008, she was unanimously chosen to be its first female President.
Author
Obeng launched her first book -Anthology of a Lifetime in July 2019. It is a selection from the distinguished scientist's talks, speeches, writings and publications produced during the last 60 years.
Research and publications
Letitia Obeng's research and publication focus on the environment, health and science education particularly in Africa. Her doctoral research investigated the aquatic stages of the Simuliidae identified as a major transmitter of the parasite for river blindness. Related to this research are her articles titled “Life-history and population studies on the Simuliidae of North Wales” and “The identification of the aquatic stages of the British Simuliidae”. In a paper titled "Environmental of Impacts of Four African Impoundments”, Dr. Obeng considers the environmental effects of four African dams: Lake Volta, Lake Kariba, Lake Kainji and Lake Nasser. Some of her other research and publications include:
The helminth fauna of rodents of the sub-family Murinae in Ghana. (1965)
Man-made lakes (1969).
Wildlife in the Volta Basin. Man-made Lakes (1969); co-authored with Asibey, E. O. A.
Volta Lake: Physical and biological aspects (1973)
Should dams be built? The Volta Lake example (1977)
Too Much or Too Little (1975)
Starvation or Bilharzia? a rural development dilemma (1978)
Man's impact on tropical rivers (1981)
Progress of Science in Africa—in Tradition, Culture and Religion (1986)
The right to health in tropical agriculture (1992)
Obeng was also the author of , a book written mainly for a non-scientific audience. Besides her science-related publications, Letitia Obeng is also the author of
Personal life and death
Obeng was the sister of the late Madam Theodosia Okoh, the designer of the Ghana flag. Her father, Very Reverend E.V. Asihene, was the Moderator of the Presbyterian Church of Ghana and her mother's name was Dora Asihene. She was married to George A. Obeng who died in 1959. They had three kids (two boys and a girl). The British Organizational theorists, professor and author Edward David Asihene "Eddie" Obeng (born 1959) is one of Letitia Obeng's children.
Obeng died on 23 March 2023, at the age of 98.
Awards and honours
From 1992 to 1993, Obeng was a Distinguished International Visitor fellow at Radcliff College. In 1997, she received the CSIR Award for Distinguished Career and Service to Science and Technology, the first female to receive such an award. Additionally, the CSIR Laboratory (known as The Letitia Obeng Block) was named after her in 1997. Letitia Obeng received Ghana's highest national award, Order of the Star of Ghana in 2006. In 2017, she received an honorary Doctor of Science degree from KNUST.
References
External links
1925 births
2023 deaths
Ghanaian parasitologists
Environmental scientists
Fellows of the Ghana Academy of Arts and Sciences
Alumni of Achimota School
Akan people
Alumni of the University of Birmingham
Alumni of the University of Liverpool
Ghanaian Presbyterians
People from Eastern Region (Ghana)
Kwame Nkrumah University of Science and Technology people
20th-century Ghanaian scientists
21st-century Ghanaian scientists | Letitia Obeng | [
"Environmental_science"
] | 1,349 | [
"Environmental scientists"
] |
47,499,046 | https://en.wikipedia.org/wiki/Ulu%20Muda%20Forest | The Greater Ulu Muda Forest Complex (GUMFC) is a large expanse of lowland dipterocarp forest in Baling and Sik Districts, Kedah, Malaysia, on the border with Thailand. The area has high biodiversity thanks to relatively low rates of poaching and human intrusion. A number of endangered species are known to be present in the GUMFC. The forest is in the Peninsular Malaysian rain forests ecoregion.
The water that it provides through the man-made Muda, Pedu and Ahning lakes provide water to the Muda agricultural area as well as much of Kedah, Penang and Perlis.
The forest has been both selectively and illegally logged in the past, possibly causing excess sedimentation of the water courses, and the future of the forest remains uncertain.
The majority of the forest is not very accessible, the easiest point of entry being the KOPAM jetty on Muda Lake.
Ulu Muda Wildlife Reserve covers an area of 1152.57 km2. The reserve adjoins San Kala Khiri National Park in Thailand.
References
Baling District
Sik District
Forests of Malaysia
Landforms of Kedah
Wildlife sanctuaries of Malaysia
Old-growth forests | Ulu Muda Forest | [
"Biology"
] | 246 | [
"Old-growth forests",
"Ecosystems"
] |
47,501,203 | https://en.wikipedia.org/wiki/Penicillium%20sabulosum | Penicillium sabulosum is an anamorph species of fungus in the genus Penicillium.
References
sabulosum
Fungi described in 1985
Fungus species | Penicillium sabulosum | [
"Biology"
] | 38 | [
"Fungi",
"Fungus species"
] |
47,501,381 | https://en.wikipedia.org/wiki/Penicillium%20sacculum | Penicillium sacculum is an anamorph species of fungus in the genus Penicillium which produces the xanthone 1-hydroxy-3-methoxy-6-sulfo-8-methylxanthone. Penicillium sacculum was isolated from the halophyte plant Atriplex
References
Further reading
sacculum
Fungi described in 1926
Fungus species | Penicillium sacculum | [
"Biology"
] | 85 | [
"Fungi",
"Fungus species"
] |
47,501,483 | https://en.wikipedia.org/wiki/Ohsawa%E2%80%93Takegoshi%20L2%20extension%20theorem | {{DISPLAYTITLE:Ohsawa–Takegoshi L2 extension theorem}}
In several complex variables, the Ohsawa–Takegoshi L2 extension theorem is a fundamental result concerning the holomorphic extension of an -holomorphic function defined on a bounded Stein manifold (such as a pseudoconvex compact set in of dimension less than ) to a domain of higher dimension, with a bound on the growth. It was discovered by Takeo Ohsawa and Kensho Takegoshi in 1987, using what have been described as ad hoc methods involving twisted Laplace–Beltrami operators, but simpler proofs have since been discovered. Many generalizations and similar results exist, and are known as theorems of Ohsawa–Takegoshi type.
See also
Suita conjecture
note
References
External links
Analytic Methods in Algebraic Geometry (OpenContent book See B5)
Mathematical theorems
Several complex variables | Ohsawa–Takegoshi L2 extension theorem | [
"Mathematics"
] | 193 | [
"Theorems in mathematical analysis",
"Functions and mappings",
"Several complex variables",
"Theorems in complex analysis",
"Mathematical objects",
"Mathematical relations"
] |
47,502,345 | https://en.wikipedia.org/wiki/ARC%20fusion%20reactor | The ARC fusion reactor (affordable, robust, compact) is a design for a compact fusion reactor developed by the Massachusetts Institute of Technology (MIT) Plasma Science and Fusion Center (PSFC). ARC aims to achieve an engineering breakeven of three (to produce three times the electricity required to operate the machine). The key technical innovation is to use high-temperature superconducting magnets in place of ITER's low-temperature superconducting magnets. The proposed device would be about half the diameter of the ITER reactor and cheaper to build.
The ARC has a conventional advanced tokamak layout. ARC uses rare-earth barium copper oxide (REBCO) high-temperature superconductor magnets in place of copper wiring or conventional low-temperature superconductors. These magnets can be run at much higher field strengths, 23 T, roughly doubling the magnetic field on the plasma axis. The confinement time for a particle in plasma varies with the square of the linear size, and power density varies with the fourth power of the magnetic field, so doubling the magnetic field offers the performance of a machine 4 times larger. The smaller size reduces construction costs, although this is offset to some degree by the expense of the REBCO magnets.
The use of REBCO may allow the magnet windings to be flexible when the machine is not operational. This would allow them to be "folded open" to allow access to the interior of the machine. This would greatly lower maintenance costs, eliminating the need to perform maintenance through small access ports using remote manipulators. If realized, this could improve the reactor's capacity factor, an important metric in power generation costs.
The first machine planned to come from the project is a scaled-down demonstrator named SPARC (as Soon as Possible ARC). It is to be built by Commonwealth Fusion Systems, with backing led by Eni, Breakthrough Energy Ventures, Khosla Ventures, Temasek, and Equinor.
History
The project was announced in 2014. The name and design were inspired by the fictional arc reactor built by Tony Stark, who attended MIT in the comic books.
The concept was born as "a project undertaken by a group of MIT students in a fusion design course. The ARC design was intended to show the capabilities of the new magnet technology by developing a design point for a plant producing as much fusion power as ITER at the smallest possible size. The result was a machine about half the linear dimension of ITER, running at 9 tesla and producing more than 500 megawatt (MW) of fusion power. The students also looked at technologies that would allow such a device to operate in steady state and produce more than of electricity."
Design features
The ARC design incorporates major departures from traditional tokamaks, while retaining conventional D–T (deuterium - tritium) fuel.
Magnetic field
To achieve a near tenfold increase in fusion power density, the design makes use of REBCO superconducting tape for its toroidal field coils. This material enables higher magnetic field strength to contain heated plasma in a smaller volume. In theory, fusion power density is proportional to the fourth power of the magnetic field strength. The most probable candidate material is yttrium barium copper oxide, with a design temperature of , allowing various coolants (e.g. liquid hydrogen, liquid neon, or helium gas) instead of the much more complicated liquid helium refrigeration chosen by ITER. The official SPARC brochure displays a YBCO cable section that is commercially available and that should allow fields up to 30 T.
ARC is planned to be a 270 MWe tokamak reactor with a major radius of , a minor radius of , and an on-axis magnetic field of .
The design point has a fusion energy gain factor Qp ≈ 13.6 (the plasma produces 13 times more fusion energy than is required to heat it), yet is fully non-inductive, with a bootstrap fraction of ~63%.
The design is enabled by the ~23 T peak field on coil. External current drive is provided by two inboard RF launchers using of lower hybrid and of ion cyclotron fast wave power. The resulting current drive provides a steady-state core plasma far from disruptive limits.
Removable vacuum vessel
The design includes a removable vacuum vessel (the solid component that separates the plasma and the surrounding vacuum from the liquid blanket). It does not require dismantling the entire device. That makes it well-suited for evaluating design changes.
Liquid blanket
Most of the solid blanket materials that surround the fusion chamber in conventional designs are replaced by a fluorine lithium beryllium (FLiBe) molten salt that can easily be circulated/replaced, reducing maintenance costs.
The liquid blanket provides neutron moderation and shielding, heat removal, and a tritium breeding ratio ≥ 1.1. The large temperature range over which FLiBe is liquid permits blanket operation at with single-phase fluid cooling and a Brayton cycle.
See also
List of fusion experiments
References
External links
Nuclear fusion
Superconductivity
Proposed fusion reactors
Tokamaks | ARC fusion reactor | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 1,055 | [
"Physical quantities",
"Superconductivity",
"Materials science",
"Condensed matter physics",
"Nuclear physics",
"Nuclear fusion",
"Electrical resistance and conductance"
] |
47,502,544 | https://en.wikipedia.org/wiki/Thymio | Thymio II is an educational robot in the 100 Euros price range. The robot was developed at the EPFL in collaboration with ECAL, both in Lausanne, Switzerland. A purely-visual programming language was developed at ETH Zurich
. All components, both hardware and software, are open source. The main features of the robot are a large number of sensors and actuators, educational interactivity based on light and touch, and a programming environment featuring graphical and text programming. Thymio has over 20 sensors and 40 lights and integrates with third party languages such as MIT's Scratch.
One of the unique features of these robots is its design, production, and commercialization by a full open-source and non-profit chain of actors. This very alternative approach has been justified by the educational goal of the project. The design has been mainly made by universities (EPFL, écal and ETHZ) within research programs (NCCR Robotics). Mechanics, electronics and software are open source. The company producing Thymio, called Mobsya is a non-profit organization.
Many articles have been written about how to teach with Thymio in the classroom including the article, "Classroom robotics: Motivating independent learning and discovery" on Robohub. Research and new Thymio projects are constantly being done as noted by IEEE. In 2020 Thymio's pedagogical design was evaluated by Education Alliance Finland. In the evaluation, a group of teacher-evaluators in Switzerland assessed Thymio's curriculum alignment, pedagogy, and usability through using a science-based product evaluation method, developed by Education Alliance Finland and Finnish educational researchers. The product evaluation was funded by Stiftung Mercator and as an outcome of the evaluation, Thymio was granted a pedagogical quality certification.
The robot is in production and distributors of Thymio include Sturiel.com and TechyKids.com.
Simulation
A simulation model of the Thymio II compatible with Aseba Studio is available in Webots and a 3D interactive model of the robot can be found here.
Contests
Since August 18, 2017, the Thymio II robot is used in various international online contest on Robotbenchmark.
References
Robots | Thymio | [
"Physics",
"Technology"
] | 465 | [
"Physical systems",
"Machines",
"Robots"
] |
47,502,870 | https://en.wikipedia.org/wiki/Membrane%20androgen%20receptor | Membrane androgen receptors (mARs) are a group of G protein-coupled receptors (GPCRs), which bind and are activated by testosterone and/or other androgens. Unlike the androgen receptor (AR), a nuclear receptor which mediates its effects via genomic mechanisms, mARs are cell surface receptors which rapidly alter cell signaling via modulation of intracellular signaling cascades. Known or proposed mARs include ZIP9 and GPRC6A.
GPRC6A has been found to be involved in testicular function and prostate cancer. mARs have also been found to be expressed in breast cancer cells. Activation of mARs by testosterone has been found to increase skeletal muscle strength, indicating potential anabolic effects. mARs have also been implicated in the antigonadotropic effects of androgens. 3α-Androstanediol, an active metabolite of dihydrotestosterone (DHT) and a weak androgen as well as a neurosteroid via acting as a positive allosteric modulator of the GABAA receptor, rapidly influences sexual receptivity and behavior in animals, an effect that is GABAA receptor-dependent.
See also
Membrane steroid receptor
References
G protein-coupled receptors
Human proteins | Membrane androgen receptor | [
"Chemistry"
] | 254 | [
"G protein-coupled receptors",
"Signal transduction"
] |
47,502,983 | https://en.wikipedia.org/wiki/Membrane%20steroid%20receptor | Membrane steroid receptors (mSRs), also called extranuclear steroid receptors, are a class of cell surface receptors activated by endogenous steroids that mediate rapid, non-genomic signaling via modulation of intracellular signaling cascades. mSRs are another means besides classical nuclear steroid hormone receptors (SHRs) for steroids to mediate their biological effects. SHRs can produce slow genomic responses or rapid, non-genomic responses in the case of mSRs.
List of membrane steroid receptors
Known groups of mSRs, by ligand, include:
Membrane sex steroid receptors
Membrane estrogen receptors (mERs) – GPER, ER-X, ERx, Gq-mER; Nav1.2; palmitoylated nuclear receptors
Membrane progesterone receptors (mPRs) – PAQRs (mPRα, mPRβ, mPRγ, mPRδ, mPRϵ); PGRMC1, PGRMC2;
Membrane androgen receptors (mARs) – GPRC6A, OXER1, ZIP9; TRPM8; Cav1.2
Membrane corticosteroid receptors
Membrane glucocorticoid receptors (mGRs) – caveolin-associated nuclear receptors; possible unidentified receptors
Membrane mineralocorticoid receptors (mMRs) – caveolin-associated NRs; diverse putative receptors
In addition, PDIA3 is a membrane receptor for the secosteroid calcitriol, the activated form of Vitamin D.
References
G protein-coupled receptors
Human proteins
Steroids
Human female endocrine system | Membrane steroid receptor | [
"Chemistry"
] | 331 | [
"G protein-coupled receptors",
"Signal transduction"
] |
47,503,508 | https://en.wikipedia.org/wiki/Eugenia%20Cheng | Eugenia Loh-Gene Cheng is a British mathematician, educator and concert pianist. Her mathematical interests include higher category theory, and as a pianist she specialises in lieder and art song. She is also known for explaining mathematics to non-mathematicians to combat math phobia, often using analogies with food and baking. Cheng is a scientist-in-residence at the School of the Art Institute of Chicago.
Early life and education
Cheng was born in Hampshire, England. She moved to Sussex at the age of one. Her family is originally from Hong Kong. Her interest in mathematics stemmed from a young age thanks largely to her mother who made mathematics a part of life.
Cheng attended Roedean School. She studied the Mathematical Tripos at the University of Cambridge, where she was a student of Gonville and Caius College, Cambridge. Her postgraduate research was supervised by Martin Hyland.
Career and research
As of 2020, Cheng is a scientist-in-residence at the School of the Art Institute of Chicago, where she teaches mathematics to arts students. Cheng formerly held academic appointments at the University of Nice Sophia Antipolis, the University of Sheffield and the University of Chicago.
She has published over a dozen research papers across several journals within her area of category theory. Former doctoral students include Nick Gurski and Thomas Cottrell.
Mathematics and baking
Cheng's research interests are in category theory, which she has written about for a general audience by using analogies from baking. Her vision is to rid the world of mathematics phobia. In How to Bake Pi, published on May 5, 2015, each chapter begins with a recipe for a dessert, to illustrate the commonalities in the methods and principles of mathematics and cooking. The book was well received and has since been translated into French.
Cheng has also written a number of papers with similar themes, such as On the perfect quantity of cream for a scone and On the perfect size for a pizza. Cheng has presented similar topics through YouTube in a light-hearted manner and has explored mathematics in other ways such as in her speech Mathematics and Lego: the untold story.
Other writing
Cheng's second book, Beyond Infinity, explains set theory for lay audiences using analogies and anecdotes, including Cantor's diagonal argument and Zeno's paradoxes. It was shortlisted for the 2017 Insight Investment Science Book Prize under the Royal Society Prizes for Science Books.
She published her third book, The Art of Logic in an Illogical World, in 2018. It explores arguments on real-world topics like same-sex marriage, white privilege, and police brutality in the United States using methods from logic, including explanations of Russell's paradox and Euclid's axioms on the way.
Cheng writes a column called Everyday Math for The Wall Street Journal on topics including probability theory, set theory, and Rubik's Cube solutions.
Music
Cheng is a pianist who specialises in lieder and art song. She was awarded the Sheila Mossman Memorial Award from the Associated Board of the Royal Schools of Music and was the first recipient of the Brighton and Hove Arts Council Award for the Musician of the Year. In Chicago, she gave a recital in the Pianoforte Chicago recital series; she performed Schwanengesang and Winterreise with Paul Geiger at Schubertiade Chicago in 2005 and 2006 respectively, and Die Schöne Müllerin with Ryan de Ryke at Schubertiade Chicago 2007. She performed lieder with tenor Nicholas Harkness in the Noontime Recital Series at the University of Chicago, the Salon Series at the Tower Club, and the Maxwell Recital Series, and she gave recitals for the Auxiliary Board Chapter of the Lyric Opera; she also performed La Traviata at the Oak Park Village Players.
In 2013, Cheng founded the Liederstube as an oasis for art song in the Fine Arts Building, in downtown Chicago. The mission of the Liederstube is to present and enjoy classical music in an intimate and informal setting. The Liederstube is a Not For Profit 501(c)(3) organisation.
Media appearances
Cheng has appeared on The Late Show with Stephen Colbert making mille-feuille with Stephen Colbert in 2015 to demonstrate exponentials. She was interviewed for the morning magazine show The Morning Shift on Chicago's Public Radio station WBEZ in 2017. She was interviewed by Jim Al-Khalili for The Life Scientific on BBC Radio 4, first broadcast in January 2018. She appeared on the WGBH podcast Innovation Hub in spring 2018.
Books
(US edition)
(original UK edition)
(UK Edition)
(UK edition)
(US edition)
(UK edition)
(US edition)
Recognition
Cheng is included in a deck of playing cards featuring notable women mathematicians published by the Association of Women in Mathematics.
References
External links
English mathematicians
Mathematics popularizers
Category theorists
British women mathematicians
1976 births
Living people
Alumni of Gonville and Caius College, Cambridge
People educated at Roedean School, East Sussex
School of the Art Institute of Chicago faculty
Academic staff of Côte d'Azur University
Academics of the University of Sheffield
British people of Hong Kong descent
Scientists from Provence-Alpes-Côte d'Azur | Eugenia Cheng | [
"Mathematics"
] | 1,061 | [
"Category theorists",
"Mathematical structures",
"Category theory"
] |
47,503,517 | https://en.wikipedia.org/wiki/Membrane%20glucocorticoid%20receptor | Membrane glucocorticoid receptors (mGRs) are a group of receptors which bind and are activated by glucocorticoids such as cortisol and corticosterone, as well as certain exogenous glucocorticoids such as dexamethasone. Unlike the classical nuclear glucocorticoid receptor (GR), which mediates its effects via genomic mechanisms, mGRs are cell surface receptors which rapidly alter cell signaling via modulation of intracellular signaling cascades. The identities of the mGRs have yet to be fully elucidated, but are thought to include membrane-associated classical GRs as well as yet-to-be-characterized G protein-coupled receptors (GPCRs). Rapid effects of dexamethasone were found not be reversed by the GR antagonist mifepristone, indicating additional receptors besides just the classical GR.
mGRs have been implicated in the rapid effects of glucocorticoids in the early central stress response via modulating neuronal activity in the hypothalamus, hippocampus, amygdala, and prefrontal cortex, among other areas. In accordance, glucocorticoids are known to affect cognition, stress-adaptive behavior, and neuroendocrine output (e.g., suppression of oxytocin and vasopressin secretion) within minutes. mGRs appear to be partially involved in the anti-inflammatory and immunosuppressant effects of glucocorticoids. mGRs are present in and appear to regulate many major bodily systems and organs, including the cardiovascular, immune, endocrine, and nervous systems, smooth and skeletal muscle, the liver, and fat tissue. mGRs appear to cooperate with, complement, and synergize with classical nuclear GRs in various ways.
See also
Membrane steroid receptor
References
G protein-coupled receptors
Glucocorticoids
Human proteins | Membrane glucocorticoid receptor | [
"Chemistry"
] | 409 | [
"G protein-coupled receptors",
"Signal transduction"
] |
47,503,721 | https://en.wikipedia.org/wiki/Membrane%20mineralocorticoid%20receptor | Membrane mineralocorticoid receptors (mMRs) or membrane aldosterone receptors are a group of receptors which bind and are activated by mineralocorticoids such as aldosterone. Unlike the classical nuclear mineralocorticoid receptor (MR), which mediates its effects via genomic mechanisms, mMRs are cell surface receptors which rapidly alter cell signaling via modulation of intracellular signaling cascades. The identities of the mMRs have yet to be fully elucidated, but are thought to include membrane-associated classical MRs as well as yet-to-be-characterized G protein-coupled receptors (GPCRs). Rapid effects of aldosterone were found not be reversed by the MR antagonist spironolactone, indicating additional receptors besides just the classical MR. It has been estimated that as much as 50% of the rapid actions of aldosterone are mediated by mMRs that are not the classical MR, based on findings of insensitivity to classical mR antagonists.
mMRs, along with membrane glucocorticoid receptors (mGRs), have been implicated in the rapid effects of mineralocorticoids in the early central stress response. Aldosterone has been found to have rapid non-genomic effects in the central nervous system, the kidneys, the cardiovascular system, and the colon.
GPER, also known as GPR30, binds and is activated by aldosterone, and may be considered an mMR, although it also binds and is activated by estradiol and is generally described as a membrane estrogen receptor (mER).
See also
Membrane steroid receptor
References
G protein-coupled receptors
Mineralocorticoids
Human proteins | Membrane mineralocorticoid receptor | [
"Chemistry"
] | 348 | [
"G protein-coupled receptors",
"Signal transduction"
] |
47,505,162 | https://en.wikipedia.org/wiki/Multipolarity%20of%20gamma%20radiation | Transitions between excited states (or excited states and the ground state) of a nuclide lead to the emission of gamma quanta. These can be classified by their multipolarity. There are two kinds: electric and magnetic multipole radiation. Each of these, being electromagnetic radiation, consists of an electric and a magnetic field.
Multipole radiation
Electric dipole, quadrupole, octupole… radiation (generally: 2pole radiation) is also designated as E1, E2, E3,… radiation (generally: E radiation).
Similarly, magnetic dipole, quadrupole, octupole… radiation (generally: 2pole radiation) is designated as M1, M2, M3,… radiation (generally: M radiation).
There is no monopole radiation ().
In quantum mechanics, angular momentum is quantized. The various multipole fields have particular values of angular momentum: E radiation carries an angular momentum in units of ; likewise, M radiation carries an angular momentum in units of . The conservation of angular momentum leads to selection rules, i.e., rules defining which multipoles may or may not be emitted in particular transitions.
To make a simple classical comparison, consider the figure of the oscillating dipole. It produces electric field lines travelling outwards, intertwined with magnetic field lines, according to Maxwell's equations. This system of field lines then corresponds to that of E1 radiation. Similar considerations hold for oscillating electric or magnetic multipoles of higher order.
Conversely, it is plausible that the multipolarity of radiation can be determined from the angular distribution of the emitted radiation.
Quantum numbers and selection rules
A state of a nuclide is described by its energy above the ground state, by its angular momentum J (in units of ), and by its parity, i.e., its behaviour under reflection (positive + or negative −). Since the spin of nucleons is ½ (in units of ), and since orbital angular momentum has integer values, J may be an integer or a half integer number.
Electric and magnetic multipole radiations of the same order (i.e., dipole, or quadrupole...) carry the same angular momentum (in units of ), but differ in parity. The following relations hold for :
Electric multipole radiation: Parity :
Here, the electric field has parity , and the magnetic field .
Magnetic multipole radiation: Parity :
Here, the electric field has parity , and the magnetic field .
The designation "electric multipole radiation" seems appropriate since the major part of that radiation is produced by the charge density in the source; conversely, the "magnetic multipole radiation" is mainly due to the current density of the source.
In electric multipole radiation, the electric field has a radial component; in magnetic multipole radiation, the magnetic field has a radial component.
An example: in the simplified decay scheme of 60Co above, the angular momenta and the parities of the various states are shown (A plus sign means even parity, a minus sign means odd parity). Consider the 1.33 MeV transition to the ground state. Clearly, this must carry away an angular momentum of 2, without change of parity. It is therefore an E2 transition. The case of the 1.17 MeV transition is a bit more complex: going from J = 4 to J = 2, all values of angular momentum from 2 to 6 could be emitted. But in practice, the smallest values are most likely, so it is also a quadrupole transition, and it is E2 since there is no parity change.
See also
Multipole expansion
Notes
References
Nuclear physics
Electromagnetic radiation | Multipolarity of gamma radiation | [
"Physics"
] | 766 | [
"Electromagnetic radiation",
"Physical phenomena",
"Radiation",
"Nuclear physics"
] |
47,506,272 | https://en.wikipedia.org/wiki/S%20Coronae%20Australis | S Coronae Australis (S CrA), is a young binary star system estimated to be around 2 million years old located in the constellation Corona Australis. It is composed of a G-type main sequence star that is about as luminous as and just over twice as massive as the Sun, and a smaller K-type main sequence star that has around 50-60% of the Sun's luminosity and 1.3 times its mass. Both stars are T Tauri stars and both show evidence of having circumstellar disks. The system is around 140 parsecs distant.
References
Corona Australis
T Tauri stars
G-type main-sequence stars
K-type main-sequence stars
Coronae Australis, S
Binary stars | S Coronae Australis | [
"Astronomy"
] | 158 | [
"Corona Australis",
"Constellations"
] |
47,506,435 | https://en.wikipedia.org/wiki/T%20Coronae%20Australis | T Coronae Australis (T CrA), is a young star in the constellation Corona Australis. It is a member of the Corona Australis star-forming region, which is located about from the Sun. It has a spectral type of F0e and is surrounded by a circumstellar disk, seen edge-on.
References
Corona Australis
Herbig Ae/Be stars
Coronae Australis, T | T Coronae Australis | [
"Astronomy"
] | 93 | [
"Corona Australis",
"Constellations"
] |
47,506,513 | https://en.wikipedia.org/wiki/1P-LSD | 1P-LSD (1-propanoyl-lysergic acid diethylamide) is a psychedelic drug of the lysergamide class that is a derivative and functional analogue of LSD and a homologue of ALD-52. It originated in 2015 when it appeared a designer drug sold online. It was first synthesized as a legal-LSD alternative by Lizard Labs, a Netherlands based research chemical laboratory. It modifies the LSD molecule by adding a propionyl group to the nitrogen atom of LSD's indole group.
Pharmacology
Like ALD-52, 1P-LSD is believed to act as a prodrug for LSD via hydrolysis of the propionyl group. When 1P-LSD is incubated in human serum, administered intravenously to rats, or administered either orally or intravenously to human subjects, high levels of LSD and relatively low levels of 1P-LSD are quickly detected, demonstrating that 1P-LSD is rapidly hydrolyzed into LSD in vivo following ingestion. Indeed, following intravenous administration in humans 1P-LSD is detectable in serum for no longer than 4 hours, after which it is completely converted to LSD. These findings are supported by the similar duration and behavioral effects of 1P-LSD and LSD in both animal and human experiments.
Effects
The subjective effects of 1P-LSD are not well defined in the scientific literature, although they are generally thought to be comparable to that of LSD. In a 2020 study, the qualitative effects of 1P-LSD and LSD were similar when measured using visual analog scales.
Legal status
As of 2015, 1P-LSD is unscheduled in the United States and Canada, but may be considered illegal if sold or used for human consumption as a structural analog of LSD under the Federal Analogue Act in the US. 1P-LSD is a prohibited or controlled substance in Australia, France, Finland, Denmark, Germany, Estonia, Japan, Latvia, Norway, Romania, Sweden, Switzerland, United Kingdom, Italy, Singapore, the Czech Republic, and Croatia. 1P-LSD has been illegal in Russia since 2017 as an LSD derivative.
See also
1cP-LSD
1B-LSD
1D-LSD
1V-LSD
ALD-52
1cP-AL-LAD
AL-LAD
ETH-LAD
1P-ETH-LAD
PRO-LAD
LSM-775
LSZ
O-Acetylpsilocin (4-AcO-DMT)
References
Designer drugs
Lysergamides
Prodrugs
Serotonin receptor agonists | 1P-LSD | [
"Chemistry"
] | 563 | [
"Chemicals in medicine",
"Prodrugs"
] |
47,506,601 | https://en.wikipedia.org/wiki/TY%20Coronae%20Australis | TY Coronae Australis (abbreviated as TY CrA), is a young star system around 3 million years old in the constellation Corona Australis. It is composed of a blue-white B-class star around triple the Sun's mass and a cooler smaller companion around half its mass (or 1.6 times that of the Sun). The system is an eclipsing binary with a period of 2.8 days.
References
Corona Australis
Herbig Ae/Be stars
Eclipsing binaries
Durchmusterung objects
Coronae Australis, TY | TY Coronae Australis | [
"Astronomy"
] | 120 | [
"Corona Australis",
"Constellations"
] |
47,507,667 | https://en.wikipedia.org/wiki/Institut%20N%C3%A9el | Institut Néel is a research laboratory in condensed matter physics located on Polygone Scientifique in Grenoble, France. It is named after scientist Louis Néel.
The institute is an independent research unit (UPR2940) of the French Centre national de la recherche scientifique created in 2007 as a reorganization of four research laboratories: the center for research in very low temperatures (Centre de Recherches sur les très basses températures (CRTBT)), the laboratory for the study of electronic properties of solids (laboratoire d’étude des propriétés électroniques des solides (LEPES)), the Louis Néel laboratory (laboratoire Louis Néel (LLN)), and the Laboratory of crystallography (Laboratoire de cristallographie (LdC)).
References
Related articles
Université Grenoble Alpes
External links
Condensed matter physics
French National Centre for Scientific Research
Science and technology in Grenoble
Neutron sources | Institut Néel | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 206 | [
"Materials science stubs",
"Phases of matter",
"Materials science",
"Condensed matter physics",
"Condensed matter stubs",
"Matter"
] |
47,507,934 | https://en.wikipedia.org/wiki/International%20Ground%20Source%20Heat%20Pump%20Association | Established in 1987, the International Ground Source Heat Pump Association (IGSHPA) is a nonprofit, membership-based organization that promotes geothermal heat pump technology. It was a outreach unit of the College of Engineering, Architecture and Technology (CEAT) at Oklahoma State University until 2020. In June 2020, the OSU Board of Regents voted to approve a transfer of IGSHPA, its intellectual property, and assets to the control of the Geothermal Exchange Organization (GEO).
Primary Efforts
IGSHPA is the main organization for establishing standards of practice and standards of design for Geothermal Heat Pump (GHP) systems in the US. Related organizations have been formed in other countries on four continents, including Australia, Canada, China, India, South Korea, and Sweden.
Conferences
Each year the association hosts an annual conference for people such as manufacturers, contractors, distributors, and drillers.
Standards
IGSHPA sets and revises standards for Geothermal Heat Pump (GHP) system installs based on ongoing research and field application results.
See also
Association of Energy Engineers
Geothermal heat pump (GHP)
Thermal battery
Renewable thermal energy
External links
International Ground Source Heat Pump Association
References
Heat pumps
Heating, ventilation, and air conditioning
Engineering organizations
Trade associations based in the United States
Energy business associations | International Ground Source Heat Pump Association | [
"Engineering"
] | 263 | [
"nan"
] |
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