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78,554,146 | https://en.wikipedia.org/wiki/C/1857%20V1%20%28Donati%E2%80%93van%20Arsdale%29 | Comet Donati–van Arsdale, formally designated as C/1857 V1, is a parabolic comet co-discovered by Giovanni Battista Donati and Robert van Arsdale a few hours apart on 10 November 1857. It was calculated to have a retrograde trajectory around the Sun.
References
External links
Non-periodic comets
Hyperbolic comets
Discoveries by amateur astronomers | C/1857 V1 (Donati–van Arsdale) | [
"Astronomy"
] | 73 | [
"Astronomy stubs",
"Comet stubs"
] |
78,554,654 | https://en.wikipedia.org/wiki/The%20Karl%20Georg%20Christian%20von%20Staudt%20Prize | The Karl Georg Christian von Staudt Prize, or von Staudt Prize for short, is a German math prize that is awarded every three to six years. The prize can be awarded to one or more mathematicians who work at a German university or research institution, provided that the stay is not temporary. It recognizes "outstanding, pioneering and published research results in the field of pure mathematics".
The award is named after Karl Georg Christian von Staudt, who held the chair of mathematics at the University of Erlangen. The Otto and Edith Haupt Foundation donated the capital for the prize money. Otto Haupt was one of Staudt's successors to the chair in Erlangen. According to the original statutes, the prize was endowed with at least 50,000 DM; in 2004, the two prize winners received a total of 30,000 euros. The current statutes (as of 2014) provide for prize money of 25,000 euros.
Award winners
Source:
1991 Hans Grauert for his work in the field of function theory
1994 Stefan Hildebrandt for his work on the calculus of variations
1997 Martin Kneser for his contributions to the theory of quadratic forms
2001 Don Zagier for his work on number theory.
2004 Günter Harder for his work on the theory of algebraic groups and Friedhelm Waldhausen for his results on three-dimensional manifolds and algebraic K-theory
2008 Gerd Faltings for his outstanding achievements in the field of theoretical mathematics, for the proofs of numerous conjectures in arithmetic geometry and for his research on cohomology and the theory of vector bundles on curves.
2013 Michael Rapoport in recognition of his work on arithmetic geometry and related areas
2022 Burkhard Wilking for the construction of metrics with non-negative sectional curvature, the rigidity theorems for manifolds of positive curvature and in particular the creative use of the Ricci flow
2025 Wolfgang Lück for his outstanding contributions to topology
References
Mathematics awards | The Karl Georg Christian von Staudt Prize | [
"Technology"
] | 404 | [
"Science and technology awards",
"Mathematics awards"
] |
77,200,903 | https://en.wikipedia.org/wiki/International%20Journal%20of%20Disaster%20Risk%20Reduction | The International Journal of Disaster Risk Reduction is a monthly peer-reviewed academic journal that focuses on disasters and mitigation solutions to enhance community preparedness and resilience. It was established in 2012 by David E. Alexander (University College London); since July 2024, Carmine Galasso (University College London) has been the editor-in-chief.
Abstracting and indexing
According to the Journal Citation Reports, the journal has a 2023 impact factor of 4.2.
References
External links
Environmental social science journals
Academic journals established in 2012
English-language journals
Elsevier academic journals
Monthly journals | International Journal of Disaster Risk Reduction | [
"Environmental_science"
] | 121 | [
"Environmental social science journals",
"Environmental social science"
] |
77,202,495 | https://en.wikipedia.org/wiki/Royal%20Center%20for%20Remote%20Sensing | The Royal Center for Remote Sensing (CRTS) is a space agency responsible for the Moroccan space program. Created by decree in December 1989 and located in Rabat, CRTS has been mandated to promote the use and development of remote sensing applications in Morocco. CRTS coordinates and implements the national remote sensing program in collaboration with ministerial departments, private operators, and Moroccan universities.
CRTS is the official distributor in Morocco of satellite images from Spot, Landsat, ERS, and the NOAA.
Internationally CRTS activities are part of cooperative and partnership relations with several national and international institutions and agencies. It actively participates in the work of the COPUOS.
Activity areas
Since its inception, CRTS has implemented several projects integrating remote sensing and GIS to meet user needs in the inventory and natural resource management, environmental protection, and land-use planning. These projects align with national development programs and are carried out in various forms (study contracts, pilot projects, national development projects, etc.). The applications developed provide strategic support to decision-makers and cover several areas:
Agriculture
Forestry and rangelands
Land use, land planning, and urbanism
Coastal areas, oceanography, and fishery resources
Geographic information management
Water resources – Desertification.
Space program
The Royal Center for Remote Sensing, in collaboration with the Institute of Aeronautics and Astronautics at Technische Universität Berlin, launched a micro Earth observation satellite as part of the TUBSAT program, Maroc-TUBSAT, on . This satellite has reached the end of its life.
See also
Mohammed VI (satellite)
List of space agencies
References
External links
Official website
Space agencies
Organizations based in Morocco
Organizations established in 1989 | Royal Center for Remote Sensing | [
"Astronomy"
] | 335 | [
"Outer space stubs",
"Outer space",
"Astronomy stubs"
] |
77,204,815 | https://en.wikipedia.org/wiki/NGC%204325 | NGC 4325 is an elliptical galaxy located about 330 million light-years away in the constellation Virgo. It was discovered by astronomer Heinrich d'Arrest on April 15, 1865, who described it as "vF, vS, iR, nf of 2". Despite being listed in the Virgo Cluster catalog as VCC 616, it is not a member of the Virgo Cluster but instead a background galaxy.
Physical characteristics
NGC 4325 exhibits star formation, with dust being observed in the galaxy. The galaxy has a radio luminosity of 32.2 × 1037 ergs, with a star formation rate of around 0.66 solar masses per year.
NGC 4325, contains several distinct, radial filaments with a complex morphology that strongly resembles NGC 1275 which lies in the core of the Perseus cluster. However unlike NGC 1275, NGC 4325 is almost completely isolated and the total X-ray mass of the NGC 4325 Group which NGC 4325 is the dominant galaxy is an order of magnitude lower.
AGN activity
Observations by the ROSAT and Chandra X-ray space telescopes reveal that a result of past AGN activity in NGC 4325, there exist X-ray cavities in the ICM of the NGC 4325 Group. These two small X-ray cavities with a diameter of around , which are hard to see in raw X-ray images due to their small size and lie to the east and west of NGC 4325. These cavities, although they might suggest a recent AGN outburst, don't have any corresponding radio emission which suggests that time has elapsed long enough to allow the radio lobes to fade. Also, instead of a large AGN outburst occurring in the past, the gas in the NGC 4325 Group seems to have cooled down in a short period of around of 50 million years after a small AGN outburst. This suggests that NGC 4325 is in a pre-outburst stage and that the rapid cooling of the gas will trigger another outburst within 50 million years.
In the core of the NGC 4325 Group encompassed by NGC 4325 at the south eastern edge of the galaxy approximately at a distance of there is an asymmetrical region of cool gas, with a temperature between 0.6 and 0.7 keV. This cool gas is aligned to the north-west though the south-east, appears to coincide with some of the brightest X-ray features within the group centre and extends a further from the center of the group. At a distance of approximately 20 kpc from the group centre, the gas distribution becomes much more spherically symmetric. This region of cool gas also corresponds to a region of excess emissions in X-rays. This region is displaced from the center of the group and is thought to have been displaced from the center of the group by ether a merger or by AGN activity. With the first explanation, NGC 4325 is slightly displaced by around from the centre of the group emission which suggests a merger might have taken place. Alternately, the two small X-ray cavities provide evidence of a past AGN outburst. It is thought that a weak AGN outburst between 10 and 100 million ago injected energy in the IGM, which generated the small cavities and displaced the displaced cool gas from the core of the group, which is now settling back down to the centre. The region of cool gas lies between the two bubbles, and may have been created by gas displaced by the X-ray cavities as they expanded.
There is also a metal-rich elongated filament structure in the core of the NGC 4325 Group that is thought to have formed from the AGN outburst from the core of NGC 4325 with the metal enrichment of the filament coming from a galactic wind.
Supermassive Black Hole
NGC 4325 contains a supermassive black hole with an estimated mass of 9.8 solar masses.
Nearby Galaxies
NGC 4325 is a member of the NGC 4325 Group, which is part of the Coma Supercluster. The NGC 4325 Group contains 28 confirmed members including NGC 4320 which is a peculiar galaxy. The NGC 4325 Group has a velocity dispersion of around 298 km and a mass of 3.2 solar masses. The presence of a metal-rich elongated filament structure in the core of the NGC 4325 along several other structures in the group including a secondary ring-like structure at a distance of from the center of the group suggest that the NGC 4325 Group is dynamically young and will evolve over time though galaxy mergers.
See also
List of NGC objects (4001–5000)
NGC 1275
References
External links
4325
040183
Virgo (constellation)
Astronomical objects discovered in 1865
Elliptical galaxies
Radio galaxies
NGC 4325 Group | NGC 4325 | [
"Astronomy"
] | 976 | [
"Virgo (constellation)",
"Constellations"
] |
77,207,015 | https://en.wikipedia.org/wiki/TOP%20Assay | The TOP Assay (Total Oxidizable Precursor Assay) is a laboratory method developed in 2012 that oxidatively converts (unknown) precursor compounds of perfluorocarboxylic acids (PFCAs) into the latter. This makes quantification possible. Potassium peroxodisulfate is used. This sum parameter can be used to determine the concentration of precursor compounds present by comparing the sample before and after the application of the TOP Assay.
Application
This method is used, for example, in the analysis of fire-fighting foams (aqueous film forming foam), textiles or water samples. Blood serum can also be analyzed in this way.
In addition to fluorotelomer compounds, hydrogen-substituted perfluorosulfonic acids (Hn-PFSAs), for example, can also be oxidized using the TOP Assay. Saturated and unsaturated perfluorosulfonic acids as well as perfluoroalkyl ether sulfonic acids, on the other hand, are stable.
Further reading
References
Laboratory techniques
Chemistry | TOP Assay | [
"Chemistry"
] | 227 | [
"nan"
] |
77,207,161 | https://en.wikipedia.org/wiki/Erd%C5%91s%E2%80%93Delange%20theorem | The Erdős–Delange theorem is a theorem in number theory concerning the distribution of prime numbers. It is named after Paul Erdős and Hubert Delange.
Let denote the number of prime factors of an integer , counted with multiplicity, and be any irrational number. The theorem states that the real numbers are asymptotically uniformly distributed modulo 1. It implies the prime number theorem.
The theorem was stated without proof in 1946 by Paul Erdős, with a remark that "the proof is not easy". Hubert Delange found a simpler proof and published it in 1958, together with two other ways of deducing it from results of Erdős and of Atle Selberg.
References
Theorems about prime numbers
Paul Erdős | Erdős–Delange theorem | [
"Mathematics"
] | 151 | [
"Number theory stubs",
"Theorems in number theory",
"Number theory",
"Theorems about prime numbers"
] |
77,207,305 | https://en.wikipedia.org/wiki/AF-353 | AF-353 is a drug which acts as an antagonist of the P2X3 homotrimeric and P2X2/3 heterotrimeric forms of the P2X purinoreceptors. It has been found to block taste responses and has been proposed as an agent for masking the bitter taste of medications.
See also
PPADS
References
Pyrimidines
Hydroquinones
Iodoarenes
Isopropyl compounds
Methoxy compounds
Diamines | AF-353 | [
"Chemistry"
] | 100 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
77,207,319 | https://en.wikipedia.org/wiki/NGC%204328 | NGC 4328 is a nucleated dwarf elliptical or lenticular galaxy located about 48 million light-years away based on observations by the Hubble Space Telescope using the TRGB distance indicator. NGC 4328 was discovered on March 21, 1784 by astronomer William Herschel and is a member of the Virgo Cluster in the "A'' subgroup. On the sky, NGC 4328 is located in the constellation Coma Berenices.
NGC 4328 is a companion of Messier 100, along with NGC 4323 and lies from Messier 100. A possible passage of NGC 4328 close to Messier 100, may explain the lopsidedness in the southwestern portion of Messier 100. However, there are no strong signs of interactions in the H I distribution of Messier 100 which may be due to an interaction between the two galaxies. Despite this, rescent observations are too shallow to detect tidal streams in the H I distribution of Messier 100 caused by a possible interaction between the two galaxies.
NGC 4328 is host to a supermassive black hole with an estimated mass of 6.1 solar masses.
See also
List of NGC objects (4001–5000)
NGC 4323
References
External links
40209
Dwarf elliptical galaxies
Coma Berenices
Messier 100
4328
Virgo Cluster
Astronomical objects discovered in 1784
Lenticular galaxies
Interacting galaxies | NGC 4328 | [
"Astronomy"
] | 272 | [
"Coma Berenices",
"Constellations"
] |
77,208,569 | https://en.wikipedia.org/wiki/H3LiIr2O6 | {{DISPLAYTITLE:H3LiIr2O6}}
H3LiIr2O6 is a material considered to best fit the archetype for being a special type of quantum spin liquid called a Kitaev spin liquid. Though known not to freeze at cold temperatures, H3LiIr2O6 is notoriously difficult to produce in a lab and is known to have disorder in it, muddying whether it was truly a spin liquid.
H3LiIr2O6 is considered to be a spin liquid that is proximate to the Kitaev-limit quantum spin liquid. Its ground state shows no magnetic order or spin freezing as expected for the spin liquid state. However, hydrogen zero-point motion and stacking faults are known to be present.
References
Liquids
Lithium compounds
Iridium compounds
Oxides | H3LiIr2O6 | [
"Physics",
"Chemistry"
] | 170 | [
"Phases of matter",
"Oxides",
"Salts",
"Matter",
"Liquids"
] |
77,209,781 | https://en.wikipedia.org/wiki/SBS%200953%2B549 | SBSS 0953+549 also known as SBS 0953+549 and QSO J0957+5440, is a quasar located in the constellation of Ursa Major. With a redshift of 2.58, the object is located 10.8 billion light-years away from Earth. It is a broad absorption-line quasar (BAL QSO) according to Sloan Digital Sky Survey. It was first studied in the 1980s, as part of the Second Byurakan Survey.
SBS 0953+549 contains a strong and weak absorption systems. It has powerful ultraviolet emission lines and an energic nuclear module. A further investigation also shows it has an emission line profile alike of P Cygni-type with Lyman α and β pairs.
References
Quasars
Ursa Major
2MASS objects
Principal Galaxies Catalogue objects
SDSS objects
Starburst galaxies
Active galaxies | SBS 0953+549 | [
"Astronomy"
] | 185 | [
"Ursa Major",
"Constellations"
] |
77,210,428 | https://en.wikipedia.org/wiki/Laura%20Irasuegi%20Otal | Laura Irasuegi Otal (26 November 1923 – 6 October 2016) was one of the Basque Niños de Rusia (Children of Russia) who were evacuated from northern Spain during the Spanish Civil War to Soviet Russia. She survived the Siege of Leningrad and trained as a civil engineer in Moscow before returning to Spain in 1956. She became the first woman civil engineer in the Basque Country's Colegio de Ingenieros de Caminos, Canales y Puertos del País Vasco.
Early life
Laura Irasuegi Otal was born in Eibar, Gipuzkoa, in what is now Basque Country in Northern Spain on 26 November 1923.
Exile
The Spanish Civil War began in 1936 and conditions became very harsh in the Second Spanish Republic controlled areas, as Nationalists led by General Francisco Franco began to take the upper hand. Children at risk from the conflict were evacuated to other countries, with evacuations organised through the National Council for Evacuated Children, created for this purpose by the Spanish Popular Front government.
2,895 children, who came to be known as the Niños de Rusia (Children of Russia), were evacuated from the Republican zone to the Soviet Union during 1937 and 1938, to avoid the rigours of war. Spanish children were also evacuated to France, Belgium, United Kingdom, Switzerland, Mexico and Denmark and were referred to as Niños de la Guerra (Children of War).
Age thirteen, Laura Irasuegi Otal was selected to be one of the children evacuated. She was assigned the number 1732 and was put on the ship Habana which left the port of Santurtzi on 12 June 1937, initially sailing to Bordeaux. The Habana was escorted by a Royal Navy ship, which ensured that, despite an encounter with a Francoist navy ship, they were eventually allowed to continue their voyage, with 4,500 children on board. At Bordeaux, 1,495 children transferred onto the merchant ship Sontay, destined for the port of Leningrad, a seven-day voyage away. The Sontay had an Asian crew, and the language barrier made communications difficult. The children travelled in the holds, in unsuitable conditions, and arrived in Leningrad dirty, with lice, colds or pneumonia. Araceli Sánchez Urquijo who travelled on the same ship later recalled "rats as big as cats" in the holds. The children were immediately seen by medical professionals. The evacuation was the second to go to the USSR.
Irasuegi was settled in one of the Las Casas de Niños, large children's houses in the town of Obninsk, about 100 kilometers from Leningrad. The Niños de Rusia were largely welcomed and well cared for in Russia. They were mostly educated in Spanish and taught to appreciate Spanish culture but using the Soviet method. Some of the children were encouraged to learn to speak Russian but not all learned it. The presence of the children was seen by the Soviet Union as a way of publicly supporting the future Spanish socialist republic which they hoped would emerge from the Civil War by caring for the next generation of their political elite.
Before the start of the Second World War, Irasuegi had begun studying in Leningrad. She survived the horrors and deprivations of first year of the Siege of Leningrad. In 1942 she was part of a group of Niños de Rusia who managed to leave the city travelling across the frozen Lake Ladoga in trucks. She was taken to the Caucasus and worked to extract silk threads to make parachutes for the war effort. She eventually arrived in the Georgian city of Tbilisi.
Studying engineering
When the war ended, Irasuegi was sent to Moscow and completed her civil engineering studies at the Moscow Power Engineering Institute. She married Anselmo Bárcena and they had two daughters, Cristina and Elena.
Return to Spain
With the death of Stalin in 1953, diplomatic relations between Spain and the Soviet Union improved a little and negotiations began about the repatriation of the Niños de Rusia exiled during the Spanish Civil War. By 1956 an agreement had been reached to allowed the now adult Niños de Rusia exiles to return to Spain.
Irasuegi and her young family returned to Errenteria in September 1956. Her return to Spain was not an easy experience. She had to complete the conversion of her civil engineering qualifications to fit Spanish requirements, which took some years. Eventually, in 1977 after achieving her requalification, she was able to join the Colegio de Ingenieros de Caminos, Canales y Puertos del País Vasco, the first Basque woman to do so. At that time there were only two women civil engineers working in Spain, Irasuegi and fellow Moscow Power Engineering Institute and Ninos Araceli Sánchez Urquijo.
Irasuegi had been a Basque speaker during her childhood but lost most of it during her time in Russia. On her return she did not have much chance to recover her lost Basque language, but when her nephews were born and she heard them speak Basque, she joined language classes at the age of 70 to be able to speak with them in Basque.
Laura Irasuegi died in Errenteria, Gipuzkoa, Basque Country in Northern Spain on 6 October 2016, age 92. At her funeral, a red flag was accompanied by Symphony No. 7 by Shostakovich, followed by a poem by Soviet poet Olga Bergoltz in memory of Irasuegi's survival of the Siege of Leningrad. The State Anthem of the Soviet Union was also played.
Commemoration
On 27 June 2023, an exhibion "Bide-ingeniaritzako euskal emakume aitzindariak” (Basque Women Pioneers of Civil Engineering)" was opened in Bilbao, at the headquarters of the College of Civil Engineering. The exhibition demonstrated women's involvement in civil engineering, a discipline traditionally dominated by men, through the story of two Basque women pioneers, Laura Irasuegi and Araceli Sánchez, both “gerrako umeak” children of the war, who left the port of Santurtzi in June 1937 and were sent to Leningrad.
References
1923 births
2016 deaths
Civil engineers
Women in engineering
Soviet people
Spanish communists
People from Eibar
Spanish women engineers
Soviet women engineers
Spanish emigrants
Exiles of the Spanish Civil War in the Soviet Union
Evacuations during the Spanish Civil War
Refugees in the Soviet Union
Child refugees
Spanish expatriates in the Soviet Union
Basque women
20th-century Spanish engineers | Laura Irasuegi Otal | [
"Engineering"
] | 1,320 | [
"Civil engineering",
"Civil engineers"
] |
77,210,919 | https://en.wikipedia.org/wiki/Becker%E2%80%93Morduchow%E2%80%93Libby%20solution | Becker–Morduchow–Libby solution is an exact solution of the compressible Navier–Stokes equations, that describes the structure of one-dimensional shock waves. The solution was discovered in a restrictive form by Richard Becker in 1922, which was generalized by Morris Morduchow and Paul A. Libby in 1949. The solution was also discovered independently by M. Roy and L. H. Thomas in 1944 The solution showed that there is a non-monotonic variation of the entropy across the shock wave. Before these works, Lord Rayleigh obtained solutions in 1910 for fluids with viscosity but without heat conductivity and for fluids with heat conductivity but without viscosity. Following this, in the same year G. I. Taylor solved the whole problem for weak shock waves by taking both viscosity and heat conductivity into account.
Mathematical description
In a frame fixed with a planar shock wave, the shock wave is steady. In this frame, the steady Navier–Stokes equations for a viscous and heat conducting gas can be written as
where is the density, is the velocity, is the pressure, is the internal energy per unit mass, is the temperature, is an effective coefficient of viscosity, is the coefficient of viscosity, is the second viscosity and is the thermal conductivity. To this set of equations, one has to prescribe an equation of state and an expression for the energy in terms of any two thermodynamics variables, say . Instead of , it is convenient to work with the specific enthalpy
Let us denote properties pertaining upstream of the shock with the subscript "" and downstream with "". The shock wave speed itself is denoted by . The first integral of the governing equations, after imposing the condition that all gradients vanish upstream, are found to be
By evaluating these on the downstream side where all gradients vanish, one recovers the familiar Rankine–Hugoniot conditions, , and Further integration of the above equations require numerical computations, except in one special case where integration can be carried out analytically.
Analytical solution
Two assumptions has to be made to facilitate explicit integration of the third equation. First, assume that the gas is ideal (polytropic since we shall assume constant values for the specific heats) in which case the equation of state is and further , where is the specific heat at constant pressure and is the specific heat ratio. The third equation then becomes
where is the Prandtl number based on ; when , say as in monoatomic gases, this Prandtl number is just the ordinary Prandtl number . The second assumption made is so that the terms inside the parenthesis becomes a total derivative, i.e., . This is a reasonably good approximation since in normal gases, Pradntl number is approximately equal to . With this approximation and integrating once more by imposing the condition that is bounded downstream, we find
This above relation indicates that the quantity is conserved everywhere, not just on the upstream and downstream side. Since for the polytropic gas , where is the specific volume and is the sound speed, the above equation provides the relation between the ratio and the corresponding velocity (or density or specific volume) ratio
,
i.e.,
where is the Mach number of the wave with respect to upstream and . Combining this with momentum and continuity integrals, we obtain the equation for as follows
We can introduce the reciprocal-viscosity-weighted coordinate
where , so that
The equation clearly exhibits the translation invariant in the -direction which can be fixed, say, by fixing the origin to be the location where the intermediate value is reached. Using this last condition, the solution to this equation is found to be
As (or, ), we have and as (or, ), we have This ends the search for the analytical solution. From here, other thermodynamics variables of interest can be evaluated. For instance, the temperature ratio is esaily to found to given by
and the specific entropy , by
The analytical solution is plotted in the figure for and . The notable feature is that the entropy does not monotonically increase across the shock wave, but it increases to a larger value and then decreases to a constant behind the shock wave. Such scenario is possible because of the heat conduction, as it will become apparent by looking at the entropy equation which is obtained from the original energy equation by substituting the thermodynamic relation , i.e.,
While the viscous dissipation associated with the term always increases the entropy, heat conduction increases the entropy in the colder layers where , whereas it decreases the entropy in the hotter layers where .
Taylor's solution: Weak shock waves
When , analytical solution is possible only in the weak shock-wave limit, as first shown by G. I. Taylor in 1910. In the weak shock-wave limit, all terms such as , etc., will be small. The thickness of the shock wave is of the order so that differentiation with respect to increases the order smallness by one; e.g. is a second-order small quantity. Without going into the details and treating the gas to a generic gas (not just polytropic), the solution for is found to be related to the steady travelling-wave solution of the Burgers' equation and is given by
where
in which is the Landau derivative (for polytropic gas ) and is a constant which when multiplied by some characteristic frequency squared provides the acoustic absorption coefficient. The specific entropy is found to be proportional to and is given by
Note that is a second-order small quantity, although is a third-order small quantity as can be inferred from the above expression which shows that for both . This is allowed since , unlike , passes through a maximum within the shock wave.
Validity of continuum hypothesis: since the thermal velocity of the molecules is of the order and the kinematic viscosity is of the order , where is the mean free path of the gas molecules,, we have ; an estimation based on heat conduction gives the same result. Combining this with the relation , shows that
i.e., the shock-wave thickness is of the order the mean free path of the molecules. However, in the continuum hypothesis, the mean free path is taken to be zero. It follows that the continuum equations alone cannot be strictly used to describe the internal structure of strong shock waves; in weak shock waves, can be made as small as possible to make large.
Rayleigh's solution
Two problems that were originally considered by Lord Rayleigh is given here.
Fluids with heat conduction and without viscosity
The problem when viscosity is neglected but heat conduction is allowed is of significant interest in astrophysical context due to presence of other heat exchange mechanisms such as radiative heat transfer, electron heat transfer in plasmas, etc. Neglect of viscosity means viscous forces in the momentum equation and the viscous dissipation in the energy equation disappear. Hence the first integral of the governing equations are simply given by
All the required ratios can be expreses in terms of immediately,
By eliminating from the last two equations, one can obtain equation , which can be integrated. It turns out there is no continuous solution for strong shock waves, precisely when
for this condition becomes
Fluids with viscosity and without heat conduction
Here continuous solutions can be found for all shock wave strengths. Further, here the entropy increases monotonically across the shock wave due to the absence of heat conduction. Here the first integrals are given by
One can eliminate the viscous terms in the last two equations and obtain a relation between and . Substituting this back in any one of the equations, we obtain an equation for , which can be integrated.
See also
Taylor–von Neumann–Sedov blast wave
References
Flow regimes
Fluid dynamics | Becker–Morduchow–Libby solution | [
"Chemistry",
"Engineering"
] | 1,596 | [
"Piping",
"Chemical engineering",
"Flow regimes",
"Fluid dynamics"
] |
77,211,023 | https://en.wikipedia.org/wiki/Text%20shaping | Text shaping is the process of converting text to glyph indices and positions as part of text rendering. It is complementary to font rendering as part of the text rendering process; font rendering is used to generate the glyphs, and text shaping decides which glyphs to render and where they should be put on the image plane. Unicode is generally used to specify the text to be rendered.
Text shaping results in substantially better results on Latin script; for some scripts with complex text layout such as Arabic script, text shaping is necessary for text to be readable at all.
Most graphical user interface systems, including those in MacOS, iOS, and Microsoft Windows have their own native text rendering engines that include text shaping. Microsoft's Uniscribe framework permits the use of pluggable shaping engines. Monotype's WorldType system also provides shaping functions.
In the open source world, HarfBuzz is a popular text shaping engine. According to HarfBuzz's developers, HarfBuzz is used by a range of software products including Android, Chrome, ChromeOS, Firefox, GNOME, GTK+, KDE, Qt, LibreOffice, OpenJDK, XeTeX, PlayStation, Microsoft Edge, Adobe Photoshop, Illustrator, InDesign, and Godot Engine.
Text shaping engines require descriptions of shaping properties and rules packaged in a format known as a shaping model. Shaping models include OpenType Layout, Graphite, and Apple Advanced Typography.
See also
Kerning
Ligature (typography)
Layout engine
Complex text layout
Line wrap and word wrap
Pagination
References
Typography | Text shaping | [
"Technology"
] | 337 | [
"Computing stubs"
] |
77,211,763 | https://en.wikipedia.org/wiki/Advanced%20Synthesis%20%26%20Catalysis | Advanced Synthesis & Catalysis is a bimonthly peer-reviewed scientific journal established in 1999 by Wiley. It covers research on homogeneous, heterogeneous, organic, and enzyme catalysis that are key technologies to achieve green synthesis, significant contributions to the same goal by synthesis design, reaction techniques, flow chemistry, and continuous processing, multiphase catalysis, green solvents, catalyst immobilization, and recycling, separation science, and process development. The editor-in-chief is Joe P. Richmond.
References
External links
Monthly journals
Catalysis
Chemical industry in Germany
Chemistry journals
Academic journals established in 1999
Wiley-VCH academic journals
English-language journals | Advanced Synthesis & Catalysis | [
"Chemistry"
] | 139 | [
"Catalysis",
"Chemical kinetics"
] |
77,212,042 | https://en.wikipedia.org/wiki/Jobless%20employed | In human resources, jobless employed is an oxymoron that refers to employees who have little to no work while remaining employed. The presence of jobless employed can negatively impact work culture and breed resentment among those who are overworked. Such positions are seen as a rejection of corporate work culture and an embrace of work-life balance and anti-work.
The transition to remote work following the COVID-19 pandemic, coupled with increased automation, outsourcing, and organizational disruption have increased the prevalence of the jobless employed. Absenteeism, a lack of middle management and disengaged managers enables the issue.
Jobless employed may be uncovered through performance audits and business process reviews, and replaced through the use of artificial intelligence driven business process automation.
The term was coined by Emily Stewart in May 2023 in a Vox article.
See also
Bullshit jobs
Quiet quitting
Lazy girl job
References
Criticism of work
Labor relations
2023 neologisms
Popular culture neologisms
Human resource management
Occupational stress
Motivation
Work
Labor | Jobless employed | [
"Biology"
] | 209 | [
"Ethology",
"Behavior",
"Motivation",
"Human behavior"
] |
77,212,117 | https://en.wikipedia.org/wiki/Agnew%27s%20theorem | Agnew's theorem, proposed by American mathematician Ralph Palmer Agnew, characterizes reorderings of terms of infinite series that preserve convergence for all series.
Statement
We call a permutation an Agnew permutation if there exists such that any interval that starts with 1 is mapped by to a union of at most intervals, i.e., , where counts the number of intervals.
Agnew's theorem. is an Agnew permutation for all converging series of real or complex terms , the series converges to the same sum.
Corollary 1. (the inverse of ) is an Agnew permutation for all diverging series of real or complex terms , the series diverges.
Corollary 2. and are Agnew permutations for all series of real or complex terms , the convergence type of the series is the same.
Usage
Agnew's theorem is useful when the convergence of has already been established: any Agnew permutation can be used to rearrange its terms while preserving convergence to the same sum.
The Corollary 2 is useful when the convergence type of is unknown: the convergence type of is the same as that of the original series.
Examples
An important class of permutations is infinite compositions of permutations in which each constituent permutation acts only on its corresponding interval (with ). Since for , we only need to consider the behavior of as increases.
Bounded groups of consecutive terms
When the sizes of all groups of consecutive terms are bounded by a constant, i.e., , and its inverse are Agnew permutations (with ), i.e., arbitrary reorderings can be applied within the groups with the convergence type preserved.
Unbounded groups of consecutive terms
When the sizes of groups of consecutive terms grow without bounds, it is necessary to look at the behavior of .
Mirroring permutations and circular shift permutations, as well as their inverses, add at most 1 interval to the main interval , hence and its inverse are Agnew permutations (with ), i.e., mirroring and circular shifting can be applied within the groups with the convergence type preserved.
A block reordering permutation with > 1 blocks and its inverse add at most intervals (when is large) to the main interval , hence and its inverse are Agnew permutations, i.e., block reordering can be applied within the groups with the convergence type preserved.
Notes
References
Mathematical theorems | Agnew's theorem | [
"Mathematics"
] | 529 | [
"Sequences and series",
"Theorems in mathematical analysis",
"Mathematical analysis",
"Mathematical structures",
"Series (mathematics)",
"Mathematical theorems",
"Calculus",
"Mathematical problems"
] |
69,675,760 | https://en.wikipedia.org/wiki/25T7-NBOMe | 25T7-NBOMe (also known as 2C-T-7-NBOMe or NBOMe-2C-T-7) is a substituted phenethylamine derivative from the 25-NB family. It acts as an agonist at the 5-HT2A and 5-HT2C serotonin receptors, has psychedelic effects and has been sold as a designer drug.
See also
2C-T-7
25E-NBOH
25P-NBOMe
References
Thioethers | 25T7-NBOMe | [
"Chemistry"
] | 115 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
69,676,148 | https://en.wikipedia.org/wiki/Howling | Howling is a vocal form of animal communication seen in most canines, particularly wolves, coyotes, foxes, and dogs, as well as cats and some species of monkeys. Howls are lengthy sustained sounds, loud and audible over long distances, often with some variation in pitch over the length of the sound. Howling is generally used by animals that engage in this behavior to signal their positions to one another, to call the pack to assemble, or to note their territory. The behavior is occasionally copied by humans, and has been noted to have varying degrees of significance in human culture.
In canines
The long-distance howling of wolves and coyotes is one way in which canines communicate. Long-distance contact calls are common in Canidae, typically in the form of either barks (termed "pulse trains") or howls (termed "long acoustic streams").
Wolves howl to assemble the pack usually before and after hunts, to pass on an alarm particularly at a den site, to locate each other during a storm, while crossing unfamiliar territory, and to communicate across great distances. Under certain conditions, wolf howls can be heard over areas of up to . The phases of the moon have no effect on wolf vocalization, and despite popular belief, wolves do not howl at the Moon.
Wolf howls are generally indistinguishable from those of large dogs. Male wolves give voice through an octave, passing to a deep bass with a stress on "O", while females produce a modulated nasal baritone with stress on "U". Pups almost never howl, while yearling wolves produce howls ending in a series of dog-like yelps.
Howling consists of a fundamental frequency that may lie between 150 and 780 Hz, and consists of up to 12 harmonically related overtones. The pitch usually remains constant or varies smoothly and may change direction as many as four or five times. Howls used for calling pack mates to a kill are long, smooth sounds similar to the beginning of the cry of a great horned owl. When pursuing prey, they emit a higher pitched howl, vibrating on two notes. When closing in on their prey, they emit a combination of a short bark and a howl. When howling together, wolves harmonize rather than chorus on the same note, thus creating the illusion of there being more wolves than there actually are. Lone wolves typically avoid howling in areas where other packs are present. Wolves from different geographic locations may howl in different fashions: the howls of European wolves are much more protracted and melodious than those of North American wolves, whose howls are louder and have a stronger emphasis on the first syllable.
One variation of the howl is accompanied by a high pitched whine, which precedes a lunging attack. Scent marking is more effective at advertising territory than howling and is often used in combination with scratch marks.
The howling of wolves and coyotes is similar, prompting early European explorers of the Americas to confuse the animals. One record from 1750 in Kaskaskia, Illinois, written by a local priest, noted that the "wolves" encountered there were smaller and less daring than European wolves. Another account from the early 1800s in Edwards County mentioned wolves howling at night, though these were likely coyotes.
In coyotes, "bark howls" may serve as both long-distance threat vocalizations and alarm calls. The sound known as 'wow-oo-wow' has been described as a "greeting song". The group yip howl is emitted when two or more pack members reunite and may be the final act of a complex greeting ceremony. Contact calls include lone howls and group howls, as well as the previously mentioned group yip howls. The lone howl is the most iconic sound of the coyote and may serve the purpose of announcing the presence of a lone individual separated from its pack. Group howls are used as both substitute group yip howls and as responses to either lone howls, group howls, or group yip howls.
Dog communication includes specific types of howls that have been identified in dogs, including:
Yip-howl – lonely, in need of companionship.
Howling – indicates the dog is present, or indicating that this is its territory.
Bark-howl, 2–3 barks followed by a mournful howl – dog is relatively isolated, locked away with no companionship, calling for company or a response from another dog.
Baying – can be heard during tracking to call pack-mates to the quarry.
The vocal repertoire of the fox, though substantial, includes fewer howling behaviors. At the age of about one month, fox kits can emit a high-pitched howl as an explosive call intended to be threatening to intruders or other cubs.
In howler monkeys
Outside of canines, the howler monkey is also noted for behavior characterized as howling. As their name suggests, vocal communication forms an important part of their social behavior. They each have an enlarged basihyal or hyoid bone, which helps them make their loud vocalizations. Group males generally call at dawn and dusk, as well as interspersed times throughout the day. Their main vocals consist of loud, deep, guttural growls or "howls". Howler monkeys are widely considered to be the loudest land animals. According to Guinness Book of World Records, their vocalizations can be heard clearly for . The function of howling is thought to relate to intergroup spacing and territory protection, as well as possibly to mate-guarding.
In human culture
Human accounts of wolf behavior are typified by depictions of howling, and this has been incorporated into fictional and mythical representations, such as the werewolf. Virgil, in his poetic work Eclogues, wrote about a man called Moeris, who used herbs and poisons picked in his native Pontus to turn himself into a wolf. An examination of Virgil's work notes that "[t]he howling of wolves is portentous; it is cited among the baleful omens at the assassination of Julius Caesar and the advent of renewed civil strife". In prose, the Satyricon, written circa AD 60 by Gaius Petronius Arbiter, one of the characters, Niceros, tells a story at a banquet about a friend who turned into a wolf (chs. 61–62). He describes the incident as follows, "When I look for my buddy I see he'd stripped and piled his clothes by the roadside... He pees in a circle round his clothes and then, just like that, turns into a wolf!... after he turned into a wolf he started howling and then ran off into the woods." Such depictions have become a staple of modern depictions of werewolves and other monstrous dogs, leading to their central position in media such as The Howling media franchise, the 2012 Korean film, Howling, and the 2015 British film, Howl. Howling by humans has historically been associated with wildness and madness.
The howling of wolves has been described as "perhaps the most evocative sound of any wild creature", alternately beautiful and dismal, and consequently recordings of howling have sometimes been incorporated into music. Although wolves howling at the Moon is a myth, it is also one that has made its way into human imagery of wolves, as with the Three Wolf Moon t-shirt meme.
See also
Animal language
Bark (sound)
Growling
Roar
Snarl
References
Bibliography
Animal sounds
Dog training and behavior | Howling | [
"Biology"
] | 1,518 | [
"Ethology",
"Behavior",
"Animal sounds"
] |
69,676,472 | https://en.wikipedia.org/wiki/Advanced%20Technology%20Airborne%20Computer | The Advanced Technology Airborne Computer (ATAC) was a product of Itek (a division of Litton Industries), used on US naval aircraft, and the NASA Galileo (spacecraft).
The ATAC was built using AMD 2901 4-bit processors and had a basic cycle time of 250 ns. It could be programmed in HAL/S, and could be microprogrammed to add new instructions. The Galileo project added four instructions.
Use on US Naval aircraft
Use by Galileo project
The Galileo Attitude and Articulation Control System (AACSE) was controlled by two Itek Advanced Technology Airborne Computers (ATAC), built using radiation-hardened 2901s. The project wrote their own GRACOS (Galileo realtime Attitude Control Operating System).
The Galileo project had radiation-hardened 2901 processors made (by Sandia National Lab) for the spacecraft.
References
Further reading
Aircraft Research aircraft
Computers | Advanced Technology Airborne Computer | [
"Technology"
] | 186 | [
"Computing stubs",
"Computers",
"Computer hardware stubs"
] |
69,676,583 | https://en.wikipedia.org/wiki/AC-90179 | AC-90179 is a piperidine derivative which acts as an inverse agonist at the 5-HT2A serotonin receptor and an antagonist at 5-HT2C. It was developed as a potential antipsychotic but was not pursued for medical applications due to poor oral bioavailability; however, it continues to be used as a tool compound in pharmacological research.
See also
Pimavanserin
Volinanserin
References
Piperidines | AC-90179 | [
"Chemistry"
] | 102 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
69,679,338 | https://en.wikipedia.org/wiki/Charmane%20Eastman | Charmane Eastman is an American academic research scientist whose career has focused on studying circadian rhythms and their relationships to sleep, jet lag, and shift work. She has also studied winter depression, more properly known as seasonal affective disorder (SAD). Of special focus are the effects of bright light and melatonin on circadian rhythms.
Background and education
Eastman received a B.S. in mathematics with a minor in physics from SUNY Albany in 1965. Then she worked as a laboratory technician at MIT, Harvard and the University of California at Berkeley. Eventually, she attended graduate school at the University of Chicago where she earned an M.S. (1976) and Ph.D. (1980) in biological psychology. Her graduate school advisor was Allan Rechtschaffen, Her dissertation was titled “Circadian rhythms of temperature, waking, and activity in the rat: dissociations, desynchronizations, and disintegrations.” She then completed a post-doctoral position in the Department of Psychiatry in 1983, also in Rechtscaffen's Sleep Lab at the University of Chicago.
Career
In 1983 Rosalind Cartwright offered Eastman a faculty position in the Psychology Department at Rush University Medical Center (RUMC), Chicago, where, in 1987, she founded and became Director of the Biological Rhythms Research Laboratory. She is currently Professor Emeritus in the Department of Psychiatry and Behavioral Sciences at RUMC.
Summary of selected contributions
Spontaneous internal desynchronization. Eastman's Ph.D. dissertation included a one oscillator computer model of human circadian rhythms that explained spontaneous internal desynchronization. This model challenged the accepted theory that human circadian rhythms are controlled by two oscillators, one for physiological rhythms like body temperature and one for sleep and wake. Her one oscillator model paved the way for the current established model showing sleep controlled by a single circadian oscillator and a homeostatic component for sleep need.
Seasonal affective disorder (SAD or winter depression). Eastman developed a novel placebo treatment that she used to demonstrate the efficacy of bright light therapy for this condition.
NASA shuttle missions. Eastman was commissioned by NASA to create light/dark schedules for space shuttle astronauts to follow before their missions. The purpose of the schedules was to gradually shift the astronauts’ internal circadian clocks until they aligned with the shift work sleep schedules required while on orbit.
Light History. Eastman's lab demonstrated that the amount of bright light that people were exposed to in the days before a procedure could affect their sensitivity to the bright lights used in laboratory experiments and treatments.
Dark length. Her laboratory demonstrated the dramatic effect that sleep length (dark length) has on the magnitude of circadian rhythm phase shifts that can be produced by bright light.
Phase Response Curves (PRCs). Eastman devised an efficient (fewer days and less expensive) method for generating PRCs in humans. PRCs are used to determine when to apply a stimulus such as bright light exposure or melatonin to phase shift circadian rhythms, to determine when the stimulus will make circadian rhythms earlier (phase advance) or later (phase delay).
Melatonin and bright light. Eastman's laboratory has conducted numerous studies using bright light or melatonin or the two combined to phase-shift human subjects in the laboratory. They generated phase response curves to two popular doses of melatonin which showed that for making circadian rhythms earlier (phase advances) melatonin was most effective when taken 5–7 hours before bedtime, rather than just before bedtime when most people take it. For making circadian rhythms later (phase delays), melatonin should be taken upon waking.
Jet lag. Eastman's lab demonstrated how to start shifting circadian rhythms before flights (using bright light, sunglasses, sleep schedules and melatonin) to reduce or eliminate jet lag.
Shift work. Eastman has designed sleep and light schedules that reduce the circadian misalignment that is the basis of many of the physical and psychological harms caused by shift work.
Blue Light. After the discovery of the new mammalian photoreceptors in the retina (distinct from rods and cones) called intrinsically photosensitive retinal ganglion cells (ipRCGs), that are most sensitive to blue light, there was much excitement in the field. Eastman's lab generated the first phase response curve to blue light. They also compared blue-enriched white light boxes with the traditional white fluorescent light boxes and found that the traditional light boxes were already emitting enough blue light for maximal results.
Racial differences in human circadian rhythms. Eastman discovered that African-Americans have shorter free-running circadian periods than European-Americans, which is an advantage in our early bird dominated society. This finding also has real-world implications with regards to shift work, jet lag, and delayed sleep phase syndrome.
Most cited publications
Baehr EK, Revelle W, Eastman CI. Individual differences in the phase and amplitude of the human circadian temperature rhythm: with an emphasis on morningness–eveningness. Journal of sleep research. 2000 Jun;9(2):117-27 (open access) (Cited 690 times, according to Google Scholar )
Eastman CI, Young MA, Fogg LF, Liu L, Meaden PM. Bright light treatment of winter depression: a placebo-controlled trial. Archives of general psychiatry. 1998 Oct 1;55(10):883-9. (open access) (Cited 518 times, according to Google Scholar.)
Hébert M, Martin SK, Lee C, Eastman CI. The effects of prior light history on the suppression of melatonin by light in humans. Journal of pineal research. 2002 Nov;33(4):198-203 (open access) (Cited 475 times, according to Google Scholar.)
Burgess HJ, Sharkey KM, Eastman CI. Bright light, dark and melatonin can promote circadian adaptation in night shift workers. Sleep medicine reviews. 2002 Oct 1;6(5):407-20. (Cited 315 times, according to Google Scholar.)
Crowley SJ, Lee C, Tseng CY, Fogg LF, Eastman CI. Combinations of bright light, scheduled dark, sunglasses, and melatonin to facilitate circadian entrainment to night shift work. Journal of biological rhythms. 2003 Dec;18(6):513-23. (open access) (Cited 272 times, according to Google Scholar.)
Awards
In 2012, she received the Excellence in Applied Circadian Rhythm Research Award from the National Sleep Foundation.
References
External links
Faculty profile, Rush University Medical Center
Biological Rhythms Research Laboratory
National Library of Medicine bibliography
"Living Legend" article published in journal Sleep Advances
University at Albany, SUNY alumni
Chronobiologists
Sleep disorders
University of Chicago alumni
Rush University faculty
Year of birth missing (living people)
Living people | Charmane Eastman | [
"Biology"
] | 1,417 | [
"Behavior",
"Sleep",
"Sleep disorders"
] |
69,680,149 | https://en.wikipedia.org/wiki/Dysprosium%20phosphide | Dysprosium phosphide is an inorganic compound of dysprosium and phosphorus with the chemical formula DyP.
Synthesis
The compound can be obtained by the reaction of phosphorus and dysprosium at high temperature.
4 Dy + P4 → 4 DyP
Physical properties
DyP has a NaCl structure (a=5.653 Å), where dysprosium is +3 valence. Its band gap is 1.15 eV, and the Hall mobility (μH) is 8.5 cm3/V·s.
DyP forms crystals of a cubic system, space group Fm3m.
Uses
The compound is a semiconductor used in high power, high frequency applications and in laser diodes.
References
Phosphides
Dysprosium compounds
Semiconductors
Rock salt crystal structure | Dysprosium phosphide | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 172 | [
"Electrical resistance and conductance",
"Physical quantities",
"Semiconductors",
"Materials",
"Electronic engineering",
"Condensed matter physics",
"Solid state engineering",
"Matter"
] |
69,680,218 | https://en.wikipedia.org/wiki/CCIR%20System%20E | CCIR System E is an analog broadcast television system used in France and Monaco, associated with monochrome 819-line high resolution broadcasts. Transmissions started in 1949 and ended in 1985.
System E specifications
Some of the important specs are listed below:
Frame rate: 25 Hz
Interlace: 2/1
Field rate: 50 Hz
Lines/frame: 819
Line rate: 20.475 kHz
Visual bandwidth: 10 MHz
Vision modulation: Positive
Preemphasis: none
Sound modulation: AM
Sound offset: +11.15 MHz on odd numbered channels, -11.15 MHz on even numbered channels
Channel bandwidth: 14 MHz
System E implementation provided very good (near HDTV) picture quality but with an uneconomical use of bandwidth. With the usual additions of sound carrier and vestigial sideband the result was a combined signal that demanded approximately two to three times the bandwidth of more moderately specified standards, even when colour was added to them (as the color subcarrier resides within the Luma signal space).
For this reason, France gradually abandoned it in favor of the 625-lines standard, implementing System L with SECAM color.
The final 819-line transmissions in Metropolitan France took place in Paris, from the Eiffel Tower, on 19 July 1983. TMC in Monaco were the last broadcasters to transmit 819-line television, closing down their System E transmitter in 1985.
Television channels were arranged as follows:
See also
CCIR System F
Broadcast television systems
Television transmitter
Transposer
Notes and references
External links
World Analogue Television Standards and Waveforms
Fernsehnormen aller Staaten und Gebiete der Welt
ITU-R recommendations
Television technology
Video formats
Broadcast engineering
CCIR System | CCIR System E | [
"Technology",
"Engineering"
] | 348 | [
"Information and communications technology",
"Broadcast engineering",
"Electronic engineering",
"Television technology"
] |
69,680,225 | https://en.wikipedia.org/wiki/CCIR%20System%20F | CCIR System F was an adaptation of System E used in Belgium (1953, RTB) and Luxembourg (1955, Télé Luxembourg). With only half the vision bandwidth and approximately half the sound carrier offset, it allowed French 819-line programming to squeeze into the 7 MHz VHF broadcast channels used in those neighboring countries, albeit with a substantial loss of horizontal resolution. Use of System F was discontinued in Belgium in February 1968, and in Luxembourg in September 1971.
Between 1976 and 1981 when French channel TF1 was switching area by area to the new analog 625-lines UHF network with SECAM colour, some transmitters and gapfillers broadcast the 819-line signal in UHF. When switching to 625-lines, most gapfillers did not change UHF channel (e.g. many gapfillers using this transmission located in French Alps near Grenoble, Mont Salève and Geneva began broadcasting on UHF channel 42, and continue to use this frequency to this day). They were switched to 625-lines in June 1981.
System F specifications
Some of the important specs are listed below:
Frame rate: 25 Hz
Interlace: 2/1
Field rate: 50 Hz
Lines/frame: 819
Line rate: 20.475 kHz
Visual bandwidth: 5 MHz
Vision modulation: Positive
Preemphasis: 50 μs
Sound modulation: AM
Sound offset: +5.5 MHz
Channel bandwidth: 7 MHz
See also
CCIR System E
Broadcast television systems
Television transmitter
Transposer
Notes and references
External links
World Analogue Television Standards and Waveforms
Fernsehnormen aller Staaten und Gebiete der Welt
ITU-R recommendations
Television technology
Video formats
Broadcast engineering
CCIR System | CCIR System F | [
"Technology",
"Engineering"
] | 347 | [
"Information and communications technology",
"Broadcast engineering",
"Electronic engineering",
"Television technology"
] |
69,680,286 | https://en.wikipedia.org/wiki/CCIR%20System%20N | CCIR System N is an analog broadcast television system introduced in 1951 and adopted by Argentina, Paraguay and Uruguay, paired with the PAL color system (PAL-N) since 1980.
It employs the 625 line/50 field per second waveform of CCIR Systems B/G, D/K, and I, but on a 6 MHz channel with a chrominance subcarrier frequency of 3.582056 MHz (similar to NTSC).
Specifications
The general System N specifications are listed below.
Frame rate: 25 Hz
Interlace: 2/1
Field rate: 50 Hz
Lines/frame: 625
Line rate: 15.625 kHz
Visual bandwidth: 4.2 MHz
Vision modulation: Negative
Preemphasis: 75 μs
Sound modulation: FM
Sound offset: +4.5 MHz
Channel bandwidth: 6 MHz
See also
PAL
PAL-N
Broadcast television systems
Multichannel Television Sound
Pan-American television frequencies
Notes and references
External links
World Analogue Television Standards and Waveforms
Fernsehnormen aller Staaten und Gebiete der Welt
ITU-R recommendations
Television technology
Video formats
Broadcast engineering
CCIR System | CCIR System N | [
"Technology",
"Engineering"
] | 229 | [
"Information and communications technology",
"Broadcast engineering",
"Electronic engineering",
"Television technology"
] |
69,680,292 | https://en.wikipedia.org/wiki/CCIR%20System%20L | CCIR System L is an analog broadcast television system used in France, Luxembourg, Monaco and Chausey. It was the last system to use positive video modulation and AM sound.
Initially adopted in the 1970s and associated with the SECAM color system (SECAM-L), it was discontinued in 2011, when France transitioned to Digital Video Broadcasting.
Specifications
The main System L specifications are listed below.
Frame rate: 25 Hz
Interlace: 2/1
Field rate: 50 Hz
Lines/frame: 625
Line rate: 15.625 kHz
Visual bandwidth: 6 MHz
Vision modulation: Positive
Preemphasis: 50 μs
Sound modulation: AM
Sound offset: -6.5 MHz
Channel bandwidth: 8 MHz
Television channels were arranged as follows:
See also
Broadcast television systems
Television transmitter
Transposer
Notes and references
External links
ITU, Characteristics of television systems
World Analogue Television Standards and Waveforms
Fernsehnormen aller Staaten und Gebiete der Welt
ITU-R recommendations
Television technology
Video formats
Broadcast engineering
CCIR System | CCIR System L | [
"Technology",
"Engineering"
] | 210 | [
"Information and communications technology",
"Broadcast engineering",
"Electronic engineering",
"Television technology"
] |
69,680,294 | https://en.wikipedia.org/wiki/CCIR%20System%20K | CCIR System K is an analog broadcast television system used in countries that adopted CCIR System D on VHF, and in Benin, Guinea, Republic of the Congo, Togo, Senegal, Burkina Faso, Burundi, Ivory Coast, Gabon, Comoros, Democratic Republic of the Congo, Madagascar, Mali, Nigeria, Réunion, Rwanda, Chad, Central African Republic, French Polynesia, New Caledonia, Wallis and Futuna, Guadeloupe, Martinique, Saint Pierre and Miquelon and French Guiana.
It is identical System D in most respects. Used only for UHF frequencies, its paired with SECAM or PAL color systems.
Specifications
Some of the important specs are listed below.
Frame rate: 25 Hz
Interlace: 2/1
Field rate: 50 Hz
Lines/frame: 625
Line rate: 15.625 kHz
Visual bandwidth: 6 MHz
Vision modulation: Negative
Preemphasis: 50 μs
Sound modulation: FM
Sound offset: +6.5 MHz
Channel bandwidth: 8 MHz
Television channels were arranged as follows:
System K1
French overseas departments and territories used a variation named System K1 for broadcast in VHF. UHF channels were similar to K.
See also
Broadcast television systems
Television transmitter
Transposer
Notes and references
External links
World Analogue Television Standards and Waveforms
Fernsehnormen aller Staaten und Gebiete der Welt
ITU-R recommendations
Television technology
Video formats
Broadcast engineering
CCIR System | CCIR System K | [
"Technology",
"Engineering"
] | 288 | [
"Information and communications technology",
"Broadcast engineering",
"Electronic engineering",
"Television technology"
] |
69,680,308 | https://en.wikipedia.org/wiki/CCIR%20System%20D | CCIR System D is an analog broadcast television system used in Bulgaria, Latvia, Lithuania, Poland, Romania, Slovakia, Czech Republic, Hungary, Albania and the People's Republic of China, Mongolia, Kyrgyzstan, North Korea, Tajikistan, Turkmenistan, Uzbekistan, Armenia, Azerbaijan, Georgia, Kazakhstan, Moldova, Russia, Ukraine and Belarus paired with the PAL/SECAM colour.
Initially known as the I.B.T.O. 625-line system this was the first 625-line system, developed by Mark Krivosheev in 1948, and later associated with the SECAM and PAL color systems. Used on VHF only in most countries, it usually combined with System K on UHF. In China, it is used for both VHF and UHF.
Specifications
The general specifications for System D are listed below:
Frame rate: 25 Hz
Interlace: 2/1
Field rate: 50 Hz
Lines/frame: 625
Line rate: 15.625 kHz
Visual bandwidth: 6 MHz
Vision modulation: Negative
Preemphasis: 50 μs
Sound modulation: FM
Sound offset: +6.5 MHz
Channel bandwidth: 8 MHz
Television channels were arranged as follows:
The original assignments of channels 25 to 57 were 2 MHz higher in frequency until c.1984. Channels 58 to 62 were deleted at this time.
See also
Broadcast television systems
Television transmitter
Transposer
References
External links
ITU, Characteristics of television systems
World Analogue Television Standards and Waveforms
ITU-R recommendations
Television technology
Video formats
Broadcast engineering
CCIR System
Television in the Soviet Union | CCIR System D | [
"Technology",
"Engineering"
] | 310 | [
"Information and communications technology",
"Broadcast engineering",
"Electronic engineering",
"Television technology"
] |
69,680,802 | https://en.wikipedia.org/wiki/Recursive%20largest%20first%20algorithm | The Recursive Largest First (RLF) algorithm is a heuristic for the NP-hard graph coloring problem. It was originally proposed by Frank Leighton in 1979.
The RLF algorithm assigns colors to a graph’s vertices by constructing each color class one at a time. It does this by identifying a maximal independent set of vertices in the graph, assigning these to the same color, and then removing these vertices from the graph. These actions are repeated on the remaining subgraph until no vertices remain.
To form high-quality solutions (solutions using few colors), the RLF algorithm uses specialized heuristic rules to try to identify "good quality" independent sets. These heuristics make the RLF algorithm exact for bipartite, cycle, and wheel graphs. In general, however, the algorithm is approximate and may well return solutions that use more colors than the graph’s chromatic number.
Description
The algorithm can be described by the following three steps. At the end of this process, gives a partition of the vertices representing a feasible -colouring of the graph .
Let be an empty solution. Also, let be the graph we wish to color, comprising a vertex set and an edge set .
Identify a maximal independent set . To do this:
The first vertex added to should be the vertex in that has the largest number of neighbors.
Subsequent vertices added to should be chosen as those that (a) are not currently adjacent to any vertex in , and (b) have a maximal number of neighbors that are adjacent to vertices in . Ties in condition (b) can be broken by selecting the vertex with the minimum number of neighbors not in . Vertices are added to in this way until it is impossible to add further vertices.
Now set and remove the vertices of from . If still contains vertices, then return to Step 2; otherwise end.
Example
Consider the graph shown on the right. This is a wheel graph and will therefore be optimally colored by RLF. Executing the algorithm results in the vertices being selected and colored in the following order:
Vertex (color 1)
Vertex , , and then (color 2)
Vertex , , and then (color 3)
This gives the final three-colored solution .
Performance
Let be the number of vertices in the graph and let be the number of edges. Using big O notation, in his original publication Leighton states the complexity of RLF to be ; however, this can be improved upon. Much of the expense of this algorithm is due to Step 2, where vertex selection is made according to the heuristic rules stated above. Indeed, each time a vertex is selected for addition to the independent set , information regarding the neighbors needs to be recalculated for each uncolored vertex. These calculations can be performed in time, meaning that the overall complexity of RLF is .
If the heuristics of Step 2 are replaced with random selection, then the complexity of this algorithm reduces to ; however, the resultant algorithm will usually return lower quality solutions compared to those of RLF. It will also now be inexact for bipartite, cycle, and wheel graphs.
In an empirical comparison by Lewis in 2021, RLF was shown to produce significantly better vertex colorings than alternative heuristics such as the greedy algorithm and the DSatur algorithm on random graphs. However, runtimes with RLF were also seen to be higher than these alternatives due to its higher overall complexity.
References
External links
High-Performance Graph Colouring Algorithms Suite of graph coloring algorithms (implemented in C++) used in the book A Guide to Graph Colouring: Algorithms and Applications (Springer International Publishers, 2021).
1979 in computing
Graph algorithms
Graph coloring | Recursive largest first algorithm | [
"Mathematics"
] | 751 | [
"Graph coloring",
"Mathematical relations",
"Graph theory"
] |
69,681,255 | https://en.wikipedia.org/wiki/Footprint%20%28company%29 | Footprint is a materials science organization that engineers fiber-based packaging in an effort to address the environmental crisis of plastic pollution. Its plant-based fiber alternatives to plastic are made from sources like double-lined kraft. These can be compostable, biodegradable, and recyclable. Footprint operates in the United States, Europe and Mexico.
History
Footprint was founded by Troy Swope, a former engineer at Intel, who became an "accidental environmentalist." Swope saw that outgassing was damaging Intel's products and thought that plastic food packaging might have the same issue outgassing on food. Troy and Footprint co-founder Yoke Chung founded Footprint in 2014.
As of 2020, Footprint has factories in the United States and Mexicali, Mexico, with around 1,500 employees. Its main base is in Gilbert, Arizona, which houses a 135,000 square foot complex.
In 2021, Footprint was named a CNBC Disruptor 50 company.
In December 2021, Footprint and Gores Holdings VIII, Inc. announced a merger acquisition that will result in Footprint becoming a publicly listed company. It is expected to list on NASDAQ under the ticker symbol "FOOT." The following September saw its valuation cut as part of an amended merger deal, but with an upsized investment, following delays in its public listing due to macroeconomic environment.
In 2021, Footprint founders Troy Swope and Yoke Chung were named to Newsweek's list of America's Greatest Disruptors: Planet Protectors.
Activities
Footprint's products are made from materials including double-lined kraft and newsprint. The organization uses things like recycled cardboard boxes, agricultural waste and virgin wood fibers to create biodegradable packaging. It owns around 240 patents for containers that can keep food safe, including packaging meant for shelves and those that can be frozen for 180 days. In the wake of plastic straw bans, Footprint makes a compostable paper straw.
Research on turtle behavior
Footprint supports the research of Christine Figgener, a marine conservation biologist who documents turtle behavior and has investigated the effect of plastics pollution on their natural habitat. Her video showing a turtle with a straw stuck in its snout garnered 37 million views as of September 2019, which raised awareness of the crisis.
Transition from plastics to alternatives
Footprint has supported Conagra Brands transition from plastic products to fiber bowls. Footprint has developed fiber-based plastic alternatives for Philips, Bose, Target, and Foxconn. Sweetgreen has switched to bowls designed by Footprint.
Sports
Food service items for the Super Bowl LIV were supplied by Footprint. These included more than 100,000 plates, bowls, cups, hot dog boards, and straws. Coolers designed by Footprint used in the Super Bowl LIV were biodegradable.
In July 2021, Footprint and the Phoenix Suns announced a naming rights partnership for Footprint Center. As part of the partnership, Footprint Center will eliminate single-use plastic from the arena.
NextGen Cup Challenge
In 2018, Footprint joined Starbucks, McDonald's, Coca-Cola Company, Yum Brands, Wendy's, and Nestlé in the NextGen Cup Challenge, which sought to identify an optimal cup design that was recyclable. Footprint's entry was called CoolTouch and debuted during Climate Week.
European Expansion
In Sept. 2021, Footprint announced plans for a European R&D center in the Netherlands that will also serve as the company's European headquarters.
References
Materials science organizations
2014 establishments in Arizona | Footprint (company) | [
"Materials_science",
"Engineering"
] | 708 | [
"Materials science organizations",
"Materials science"
] |
69,682,360 | https://en.wikipedia.org/wiki/Shot%20peen%20forming | Shot peen forming is a specialized application of shot peening for forming metal sheets into complex shapes. The compressive stresses induced by the impact of the shot can be used to change the shape of the component into a desired contour.
Shot peen forming is a dieless process generally performed at room temperature. It was first used for forming the wing skins of airplanes at Lockheed Aircraft Corporation during the 1940s and was patented by that company as a "Method of cold forming sheets" in 1951.
Today it is widely used in the aerospace industry for shaping wing skins and can also be used for forming aircraft fuselage skins and rocket tank panels.
References
Shot peening
Metal forming | Shot peen forming | [
"Materials_science"
] | 134 | [
"Strengthening mechanisms of materials",
"Shot peening"
] |
69,682,723 | https://en.wikipedia.org/wiki/Pyrrole-2-carboxylic%20acid | Pyrrole-2-carboxylic acid is an organic compound with the formula HNC4H3CO2H. It is one of two monocarboxylic acids of pyrrole. It is a white solid. It arises in nature by dehydrogenation of the amino acid proline. It also arises by carboxylation of pyrrole. The ethyl ester of this acid is readily prepared from pyrrole.
References
Carboxylic acids | Pyrrole-2-carboxylic acid | [
"Chemistry"
] | 107 | [
"Carboxylic acids",
"Functional groups"
] |
69,684,274 | https://en.wikipedia.org/wiki/Hinko%20Smrekar | Hinko Smrekar (13 July 1883 – 1 October 1942) was a Slovenian painter, draughtsman, caricaturist, graphic artist, and illustrator. Smrekar was a member of the Vesna Art Club, which was active in Vienna, and a partisan in the Liberation Front of the Slovene Nation during the Nazi occupation of Yugoslavia.
The Hinko Smrekar Primary School in Ljubljana and the Hinko Smrekar Prize in Celje, the highest Slovenian award in the field of illustration (since 1993), are named after him. At the time when, as a collaborator of the Slovene Liberation Front, he was hastily shot by the Italian fascists in the vicinity of the gravel pit used for summary executions (now the Gramozna Jama Memorial), he was living in the "Villa Kurnik" on Alešovčeva Street (No 38) in Šiška. He is buried in the Memorial Park of Fallen Combatants and Hostages at Žale.
Biography
Smrekar was born in Ljubljana. After the 1895 earthquake, Smrekar's house collapsed due to instability, and his family moved several times afterwards. The Smrekars lived for a while in Kranj, where his father, who worked as a postman in Kranj, died in 1906.
Smrekar was a gifted child and already in grammar school he achieved a reputation as a master artist. He was also a diligent student and enrolled at the Innsbruck Law School in 1901. He lasted 4 semesters at law school, but the day before his first national exam, he sold all his books out of fear and drank the proceeds. This was a turning point in his life, at which he decided to dedicate his life to art. Although he never completed his academic education, he acquired extensive knowledge in various humanities and was also a polyglot.
In 1903, the Vesna Art Club was founded, which Hinko also joined. There he met Ivan Cankar and made several covers for his books. In 1905, he began publishing his satirical witty drawings in the Ljubljana humorous newspaper Osa. In that year, Smrekar, together with Maksim Gaspari, visited the art centre of Munich for the first time, where he returned for both short and long periods throughout his life.
Smrekar was also the author of the first tarok book published in Slovenia, the so-called "Slavic Tarok", printed between 1910 and 1912. In the years before and during the First World War, Smrekar's drawing skills did not rest, and shortly before the end of the war he was given the assignment he had long wanted: to illustrate Fran Levstik's Martin Krpan for the New Publishing House. Shortly after the war, he contracted a severe nervous disease. In 1920 and 1921 he tried to recover in a sanatorium near Graz, but his treatment took several years.
Then he started working again and tried to publish his own comic newspaper, Pikapok. However, tragedy struck in 1927 when his mother died and he was left alone. Because of his low income, he had to move out and it took him two years to build a small house where he could teach his drawing students. Due to a lack of clients, he began to focus on youth illustration. His most recent work as an illustrator was his drawings, images and initials for the collection Seven Andersen Fairy Tales for Wise Men and Women.
After the outbreak of World War II in Slovenia, he was captured by the fascists on a street march in late September 1942. Smrekar was brutally interrogated and hastily shot on 1 October of the same year in the Gravel Pit in Ljubljana. There were no friends or acquaintances at the funeral, but the next day his grave was covered with flowers. In the political newspaper Jutro, Elko Justin published an oblique obituary for his friend: a broken spruce tree ("smreka" in Slovenian) is piled on top of the impoverished coffin, which has been nailed with a single carved sheet, and an upside-down letter R lies across the name plate bearing the word "", meaning "the end" - a rebus of Smrekar's name. In October 1942, the news of his death was published in the illegal newspaper Slovenski poročevalec ("Slovenian Reporter").
Work and meaning
Smrekar's work is extremely colourful. He worked with all motifs, in all techniques, serious, sad, grotesque, funny, portraits, landscapes, romantic, naturalistic, national and international. He enjoyed using themes from folk tales and folk celebrations, and looked for genre motifs from the lives of ordinary people, especially peasants.
He had already resisted the war between 1914 and 1918, both personally and artistically. Two of the greatest works of Slovenian graphic art were produced in those years - the cycle of anti-war caricatures Črnovojnik ("The Black Warrior"), in which the artist humorously described his inter-war experiences, and the illustrations of Martin Krpan. These were the first illustrations of the story, which set the example for later ones, such as those by Tone Kralj. From 1939 to 1942 he worked on the collective experience of war psychosis.
References
Sources
Karel Dobida, 1957: Hinko Smrekar. Ljubljana: COBISS
Karel Dobida:"Smrekar, Hinko". Slovenski biografski leksikon. Slovenska biografija. Ljubljana: ZRC SAZU, 2013 (online version)
Filip Kalan: "Likovna umetnost - Iz zapiskov o slovenski vojni grafiki", Novi svet 5, št. 9 (1950) (Dokument v zbirki Digitalne knjižnice Slovenije online version)
OBL Austrian Centre for Digital Humanities and Cultural Heritage: Österreichisches Biographisches Lexikon - Smrekar, Hinko (Henrik), 1883-1942 Graphiker und Maler
Obrazi slovenskich pokrajin: Smrekar, Hinko
Dnevnik70let: Smrekarjeve karikature in tožbe by Darinka Kladnik, 17 Dec 2011
External links
1883 births
1942 deaths
20th-century executions
20th-century Slovenian painters
20th-century Slovenian male artists
Artists from Ljubljana
Draughtsmen
Slovene resistance members
Slovenian anti-fascists
Slovenian caricaturists
Slovenian comics artists
Slovenian illustrators
Slovenian male painters
Slovenian people executed by Nazi Germany
People executed by Nazi Germany by firearm | Hinko Smrekar | [
"Engineering"
] | 1,354 | [
"Design engineering",
"Draughtsmen"
] |
69,685,037 | https://en.wikipedia.org/wiki/Thiophene-2-carboxylic%20acid | Thiophene-2-carboxylic acid is an organic compound with the formula SC4H3CO2H. It is one of two monocarboxylic acids of thiophene, the other being thiophene-3-carboxylic acid. Copper(I) thiophene-2-carboxylate is a catalyst for Ullmann coupling reactions.
Synthesis
It can be prepared by the oxidation of thiophene-2-carboxaldehyde or, more practically, 2-acetylthiophene.
Applications and reactions
Upon treatment with LDA, thiophene-2-carboxylic acid undergoes double deprotonation to give the 5-lithio derivative, a precursor to many 5-substituted derivatives.
Thiophene-2-carboxylic acid has been widely studied as a substrate in coupling reactions and olefinations.
References
Thiophenes
Carboxylic acids | Thiophene-2-carboxylic acid | [
"Chemistry"
] | 205 | [
"Carboxylic acids",
"Functional groups"
] |
69,685,595 | https://en.wikipedia.org/wiki/Iota%20Octantis | Iota Octantis, Latinized, from ι Octantis is a double star in the southern circumpolar constellation Octans. The "A" component has an apparent magnitude of 5.83, making it faintly visible to the naked eye under ideal conditions, but the "B" component can't be seen due to its faintness. The system is located at a distance of 350 light years based on its annual parallax shift, but is drifting away at a rate of .
Iota Octantis A has a classification of K0 III, which indicates that it is an evolved K-type star that exhausted hydrogen at its core and left the main sequence. It has an angular diameter of , which yields a radius 12.43 times that of the Sun at its estimated distance. At present Iota Octantis A has 2.49 times the mass of the Sun and radiates at 81 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of , which gives it an orangish-yellow hue. Iota Octantis is metal deficient and spins slowly with a projected rotational velocity of .
Eggleton et al. states that both stars have similar spectral types, but there is a faint tenth magnitude companion with a classification of F8 located away, which is unrelated to the two.
References
Octans
K-type giants
111482
063031
4870
Durchmusterung objects
Double stars
Octantis, 16 | Iota Octantis | [
"Astronomy"
] | 304 | [
"Octans",
"Constellations"
] |
69,687,005 | https://en.wikipedia.org/wiki/Samsung%20Galaxy%20A53%205G | The Samsung Galaxy A53 5G is a mid-range Galaxy phone developed and manufactured by Samsung Electronics as a part of its Galaxy
A series. The phone was announced on 17 March 2022 at Samsung Galaxy Unpacked event alongside the Galaxy A33 5G and Galaxy A73 5G.
Galaxy A53 5G Phone's price is $449 for a 128 GB model. The size of the screen is 6.5-inch which runs on Samsung's Exynos 1280 processor. Galaxy A53 has quad-camera system featuring 64 MP main camera with 32 MP front camera. Galaxy A53 is the first Samsung's A series device to get 5 years of software updates.
Design
The display is made of Corning Gorilla Glass 5. The back panel and side are made of frosted plastic.
The design of the Galaxy A53 looks almost similar to its predecessor, but the rear panel is now completely flat, and the transition between the rear panel and the camera unit is smoother. Also Galaxy A53 5G has protection against moisture and dust according to the IP67 standard.
Below are USB-C connector, speaker, microphone and depending on the version slot for 1 SIM card and microSD memory card up to 1 TB or hybrid slot for 2 SIM cards. The second microphone is located on top. On the right side are the volume buttons and the smartphone lock button.
The smartphone is sold in 4 colors: black (Awesome Black), white (Awesome White), blue (Awesome Blue) and orange (Awesome Peach).
Specifications
Hardware
The Galaxy A53 5G is a smartphone with a slate-type factor form, which is 159.6 × 74.8 × 8.1 mm in size and weighs 189 grams.
The device is equipped with GSM, HSPA, LTE and 5G connectivity, Wi-Fi 802.11 a/b/g/n/ac dual-band with Bluetooth 5.1, Wi-Fi Direct support and hotspot support with A2DP and LE, GPS with BeiDou, Galileo, GLONASS and QZSS and NFC. It has a USB Type-C 2.0 port. It is dust and water resistant with IP67 certification.
Display
It has a 6.5 inch diagonal Super AMOLED display with Infinity-O-type punch-hole camera, rounded corners, FHD+ resolution of 1080 × 2400 pixels, with an adaptive refresh rate up to 120 Hz protected by Gorilla Glass 5.
Battery
The 5000mAh lithium polymer battery being non-removable and supporting fast charging at 25 W means that the device has a high-capacity battery that can last a long time between charges and can be charged quickly when needed.
Processor
The device has a Samsung Exynos 1280 chipset with an octa-core CPU (2 cores at 2.4 GHz + 6 cores at 2 GHz) that enables the device to handle demanding tasks and optimize power consumption. It has UFS 2.0 internal memory with 128/256 GB storage and microSD expandable up to 1 TB. The RAM is either 6 or 8 GB (depending on the version chosen), which allows for smooth multitasking and running demanding apps.
Camera
The devices rear camera array features four cameras, including a 64 MP main camera, a 12 MP ultrawide camera, a 5 MP macro camera, and a 5 MP depth camera. These cameras work together to capture high-quality photos and videos from different perspectives. In addition to the main camera's high resolution and the ultrawide camera's wider field of view, the macro camera is designed for capturing extreme close-up shots of small objects, while the depth camera captures depth information to create portrait mode photos with a blurred background or add depth information to other types of photos and videos for a more immersive experience.
Software
The phone comes with Android 12 and One UI 4.1 and this Galaxy device is expected to get updated until One UI 8.1
References
A53 5G
Mobile phones introduced in 2022
Android (operating system) devices
Galaxy A53 5G
Phablets
Mobile phones with multiple rear cameras
Mobile phones with 4K video recording
Discontinued Samsung Galaxy smartphones | Samsung Galaxy A53 5G | [
"Technology"
] | 858 | [
"Crossover devices",
"Phablets"
] |
69,687,009 | https://en.wikipedia.org/wiki/Samsung%20Galaxy%20A73%205G | The Samsung Galaxy A73 5G is a mid-high range Android-based smartphone developed and manufactured by Samsung Electronics as a part of its Galaxy A series. The phone was announced on 17 March 2022 at Samsung Galaxy Unpacked event alongside the Galaxy A33 5G and Galaxy A53 5G.
Design
The screen is made of Corning Gorilla Glass 5. The back panel and side are made of frosted plastic.
The smartphone is similar in design to its predecessor, but as in the Samsung Galaxy A33 5G and Samsung Galaxy A53 5G, the rear panel is now completely flat, and the transition between the rear panel and the camera unit is smoother. The Galaxy A73 5G, unlike the Samsung Galaxy A72, does not have a 3.5 mm audio jack. The smartphone also has protection against moisture and dust according to the IP67 standard.
Below are the USB-C connector, speaker and microphone. Depending on the version, there is a slot for 1 SIM card and a microSD memory card up to 1 TB or a hybrid slot for 2 SIM cards or 1 SIM card and a microSD memory card up to 1 TB and a second microphone. On the right side are the volume buttons and the smartphone lock button.
Samsung Galaxy A73 5G is sold in 3 colors: green (Awesome Mint), gray (Awesome Gray) and white (Awesome White).
Specifications
Hardware
The Galaxy A73 5G is a smartphone with a slate-type factor form, which is 159.6 mm × 74.8 mm × 8.1 mm in size and weighs 189 grams.
The device is equipped with GSM, HSPA, LTE and 5G connectivity, Wi-Fi 802.A/b/g/n/ac/ax dual-band with Bluetooth 5 Wi-Fi Direct support and hotspot support.0 with A2DP and LE, GPS with BeiDou, Galileo, GLONASS and QZSS and NFC. It has a USB-C 2.0 port and no 3.5 mm audio jack input. It is resistant to water and powder with IP67 certification.
Display
It has a 6.7-inch diagonal touchscreen, Super AMOLED+ Infinity-O, rounded corners and FHD+ resolution of 1080 × 2400 pixels. The screen supports a 120 Hz refresh rate. For screen protection it uses Gorilla Glass 5.
Battery
The Samsung Galaxy A73 5G comes with a high-capacity 5000 mAh lithium polymer battery that is built-in and cannot be removed from the device. This battery supports fast 25-watt charging technology.
Processor
The chipset is a Qualcomm Snapdragon 778G with an octagonal CPU (4 cores at 2.4 GHz + 4 cores at 1.8 GHz). UFS type 2 internal memory. 1 is 128/256 GB expandable with microSD up to 1 TB, while the RAM is 6 or 8 GB (depending on the version chosen).
Camera
The rear camera has a 108 MP main sensor with an f/1.8 opening, equipped with a PDAF, OIS, HDR mode and a flash LED mode, capable of recording up to 4K to 30 frames per second; while the front camera is a single 32 MP camera with a same recording capacity.
Software
The device comes with the Android 12 operating system pre-installed, which is the latest version of Android available at the time of its release. Android 12 is known for its sleek design, intuitive interface, and improved privacy and security features.
In addition to Android 12, the Samsung Galaxy A73 5G also comes with One UI 4.1, which is Samsung's proprietary user interface. One UI 4.1 is designed to provide a seamless and user-friendly experience for Samsung device users. It includes features such as split-screen multitasking, a customizable home screen, and improved battery life management.
Furthermore, the Samsung Galaxy A73 5G is also upgradable to Android 13 with One UI 5.1. Android 13 is expected to be the next major version of the Android operating system, and it is expected to include even more advanced features and improvements over its predecessor. One UI 5.1 is also expected to include enhancements and optimizations for the Samsung Galaxy A73 5G specifically.
References
Samsung Galaxy
Mobile phones introduced in 2022
Android (operating system) devices
Samsung mobile phones
Phablets
Mobile phones with multiple rear cameras
Mobile phones with 4K video recording
Discontinued Samsung Galaxy smartphones | Samsung Galaxy A73 5G | [
"Technology"
] | 935 | [
"Crossover devices",
"Phablets"
] |
69,687,865 | https://en.wikipedia.org/wiki/Elburt%20F.%20Osborn | Elburt Franklin Osborn (August 13, 1911 – January 19, 1998) was an American geochemist and educator. He served as the 13th director of the U.S. Bureau of Mines.
Early life
Elburt Franklin Osborn was born on August 13, 1911, in Kishwaukee, Illinois to Anna (née Sherman) and William Franklin Osborn. Osborn graduated with a Bachelor of Arts in geology from DePauw University in 1932. He received a Master of Science in petrology from Northwestern University in 1934 and a PhD in petrology from the California Institute of Technology in 1938.
Career
In 1938, Osborn joined the Geophysical Lab at the Carnegie Institution for Science in Washington, D.C. He also served as a consultant of ballistic problems for Division I of the National Defense Research Committee during World War II. His work related to gun barrel erosion and internal ballistics.
In 1946, Osborn joined Pennsylvania State University as a professor of geochemistry and chairman of the earth sciences department. He then served as associate dean from 1952 to 1953 and served as dean of the College of Mineral Studies from 1953 to 1958. In 1952, Osborn, along with Thomas Bates, founded the Materials Characterization Laboratory. Osborn and his students have received international recognition for their research in the field of high temperature reactions as applied to iron and steel technology and to volcanic phenomena. He became the vice president for research at Penn State in 1959 and served in that role until 1970. During his 11 years as vice president, he helped to quadruple research budgets at Penn State (from million to million). He remained affiliated with the university until resigning on August 14, 1971. Under his leadership, Penn State introduced the first interdisciplinary curriculum in solid state technology in 1960 and opened the Interdisciplinary Materials Research Laboratory in 1962.
Osborn was appointed director of the U.S. Bureau of Mines on October 23, 1970. As director, he helped establish the Pennsylvania Mining and Mineral Resources Research Institute. He left the role on September 30, 1973. In 1973, he became a professor at the geophysical laboratory of Carnegie Institute. From 1978 to 1987, he served as a senior research fellow at Carnegie Institute. In 1974, Osborn was named as the chairman of the National Research Council's Board on Mineral Resources.
He served as president of the Mineralogical Society of America in 1960, the American Ceramic Society in 1964, the Geochemical Society in 1967, the Society of Economic Geologists in 1971, and the Geophysical Society of America. He was a fellow of the Geological Society of America, the Mineralogical Society of America, the American Association for the Advancement of Science, the American Geophysical Union and the American Ceramic Society. He was elected as a member of the National Academy of Engineering in 1968 for "advances in ceramics, slag, mineral, and steel technologies". He was also an honorary member of the Canadian Ceramic Society and a member of the National Science Foundation.
Personal life and death
Osborn married Jean McLeod Thomson on August 12, 1939. Together, they had two children, James and Ian.
Osborn died on January 19, 1998, at his home in State College, Pennsylvania. He was interred at Centre County Memorial Park in Centre County, Pennsylvania.
Awards
Osborn received an honorary Doctor of Science degree from Alfred University in 1965 and an honorary Doctor of Science degree from Ohio State University in 1972. He was awarded the Mineralogical Society of America's Roebling Medal in 1972. Osborn was awarded the American Ceramic Society's Albert Victor Bleininger Memorial Award in 1976.
References
1911 births
1998 deaths
People from Winnebago County, Illinois
DePauw University alumni
Northwestern University alumni
California Institute of Technology alumni
Pennsylvania State University faculty
United States Bureau of Mines personnel
American geochemists
Fellows of the Geological Society of America
Fellows of the American Ceramic Society
Fellows of the American Association for the Advancement of Science
Fellows of the American Geophysical Union
Members of the United States National Academy of Engineering
Presidents of the Geochemical Society
20th-century American chemists
Fellows of the Mineralogical Society of America | Elburt F. Osborn | [
"Chemistry"
] | 812 | [
"Geochemists",
"Presidents of the Geochemical Society",
"American geochemists"
] |
68,393,143 | https://en.wikipedia.org/wiki/Furegrelate | Furegrelate, also known as 5-(3-pyridinylmethyl)benzofurancarboxylic acid, is a chemical compound with thromboxane enzyme inhibiting properties that was originally developed by Pharmacia Corporation as a drug to treat arrhythmias, ischaemic heart disorders, and thrombosis but was discontinued. It is commercially available in the form furegrelate sodium salt.
Furegrelate is able to bind to the enzyme thromboxane A2 synthase. By binding to thromboxane A2 synthase it negates the effects and prevents it from acting like a vasoconstrictor. Because of this Furegrelate is capable of preventing several diseases involving thrombosis, the occurrence of blood clots that block veins or arteries. Furegrelate is orally administrable and rapidly absorbed in the blood. Currently no adverse effects of furegrelate are known due to a lack of research, although thromboxane A2 synthase devisentie could be a potential risk.
Structure activity relationships
5-(3-Pyridinylmethyl)benzofurancarboxylic acid, is an achiral, organic molecule containing a pyridine ring and a carboxylic acid group. The compound is a member of the benzofurans and can be found in a variety of forms (free-base, sodium salt and hydrochloric acid salt) all of them variations of the carboxylic acid functionality.
Furegrelate in its free-base form is not well-soluble in pH-neutral aqueous environments and can therefore pass the lipophilic cell membranes.
The pyridine functionality of Furegrelate has biologically the most interesting properties. Pyridines are known to have an inhibiting effect on the synthesis of TxA2 Thromboxane - known for platelet aggregation and vasoconstricting properties. Research also showed that pyridines substituted at the -3’ position with aryl or alkyl carboxylic acid groups, undergo a major enhancement of specifically TxA2 synthase inhibition, probably due to a more favourable molecular orientation during the reaction.
Synthesis
Furegrelate is a synthetic compound that cannot be synthesised by the human body. Several pathways were proposed for the synthesis of Furegrelate sodium salt and related compounds by Johnson et al. and is presented in Figure 1. The nitro group of the starting material, 3-(4-nitrobenzyl)pyridine (1), is reduced using hydrogen over palladium on activated carbon to form 3-(4-aminobenzyl)pyridine (2). In the following step, nitric acid was created in situ by mixing sodium nitrite with sulphuric acid in ice-cold water. The nitric acid attaches to the amino group, forming a diazo group. The hydroxyl group is obtained by stirring the diazo intermediate in a hot aqueous sulphuric acid solution, giving product 3. Product 3 was formylated on the ortho-position relative to the hydroxyl group, using an adjusted Duff reaction using hexamine and trifluoroacetic acid (TFA). In the Duff reaction, the formyl carbon is created from hexamine, leading to product 3-(3-hydroxy-4-formylbenzyl)pyridine, 4. Benzofuran-2-carboxylic acid ethyl ester (5), was obtained using a base-promoted reaction with diethyl bromomalonate and sodium hydride on product 4. To increase NaH solubility, a crown ether was used. Ester product 5 was then transformed to Furegrelate sodium salt 6 using methanol and sodium hydroxide in water. Johnson and co-workers synthesised also two other Furegrelate chemical forms: the free-base 7 and hydrochloric acid salt 8 forms.
The starting material, 3-(4-nitrobenzyl)pyridine (1), is commercially available but can also be synthesised from the pyridine-derivative nicotinic acid, as shown in Figure 2. In the first step, nicotinic acid is chlorinated with SOCl3 after which a Friedel-Crafts acylation is performed to form 3-benzoyl pyridine. This compound is reduced using hydrogen gas in combination with a palladium catalyst, creating 3-benzylpyridine. 3-Benzylpyridine can be converted to 3-(4-nitrobenzyl)pyridine using ammonium nitrate and trifluoroacetic anhydride (TFAA) in chloroform. Various intermediate compounds are commercially available, or can be synthesised in multiple ways, but a complete synthetic proposal was made to indicate the synthetic options.
Available forms
Only one form of furegrelate is commercially available (see 2 structure and reactivity). Its physical form is a crystalline solid. It is sold as a sodium salt.
Pharmacology
Mechanisms of action
Furegrelate is an enzyme inhibitor. It combines with the enzyme thromboxane A2 synthase to prevent the normal substrate-enzyme combination and the catalytic reaction. Thromboxane A2, the compound synthesized by this enzyme, promotes the aggregation of platelets and is a vasoconstrictor. The compound plays a role in several diseases involving thrombosis, the occurrence of blood clots that block veins or arteries. Thromboxane is synthesized from a fatty acid called arachidonic acid. In platelets this fatty acid is metabolized to an endoperoxide called prostaglandin H2 by the enzyme cyclooxygenase 1. This endoperoxide is in turn metabolized to thromboxane A2 by thromboxane A2 synthase, a cytochrome P450 enzyme that occurs in the endoplasmic reticulum membrane.
Multiple cyclooxygenase inhibitors are already used as drugs against thrombotic diseases. These drugs inhibit both the production of thromboxane and prostacyclin. Furegrelate however, specifically inhibits thromboxane A2 synthase.
Metabolism
The route of administration of furegrelate is oral. The absorption and disposition of the parent drug in male volunteers have been studied after single- and multiple-dose oral administration. The results from the single-dose study indicate that furegrelate is rapidly absorbed in the blood, within maximally 1.0 to 1.7 hr. Distribution, metabolism and elimination happened with a rate constant of 0.12 to 0.17 hr-1. Furegrelate is primarily eliminated by the kidney, with 62 to 78% of the dose excreted as parent drug.
Dog experiments indicated that furegrelate is rapidly distributed. The half‐life of the compound was 132 min after an intravenous dose. Oral exposure to the drug had similar absorption and elimination kinetics as the intravenous results. The bioavailability of furegrelate dosed orally was either around 80% based on measurements of the blood concentration or more than 90% based on urinary excretion of the parent compound. Oral absorption of the drug in dogs occurred rapidly. The plasma levels reached a peak in one to two hours after ingestion. The drug was measurable in blood within 30 minutes. Thromboxane A2 is hydrated within about 30 seconds to the biologically inactive thromboxane B2. For this reason thromboxane B2 can be used as an indicator for the inhibition of thromboxane A2 synthase, and thus the presence of furegrelate.
Adverse effects
Current studies show no negative side effects of furegrelate due to off target effects in either humans or dogs. Furegrelate does not appear to show any inhibitory effect on thrombin-stimulated PGI2 biosynthesis in human endothelial cells, the 5-lipoxygenase in human neutrophils, or the cyclo-oxygenase in a variety of test systems.
“Studies failed to detect major off-target effects in preclinical testing in dogs or in Phase 1 clinical trials using healthy adult human subjects.”
A possible adverse effect of furegrelate would be thromboxane synthase deficiency due to either too high of a dosage or due to too long administration. Thromboxane synthase deficiency is characterized by mucocutaneous, gastrointestinal, or surgical bleeding.
However, this effect has not been studied yet, due to a lack of research in high dosage or long term administration of furegrelate.
Toxicity
The toxicological properties have not been thoroughly investigated.
Animal studies
The effects of furegrelate sodium have been tested using piglets. Three groups of piglets were compared. The first group of piglets were exposed to 21 days of normoxia (N; oxygen tension of 21% FIO2), the second group was exposed to chronic hypoxia (CH; low oxygen tension, 10% FIO2), the third group was exposed to the same chronic hypoxia as group 2, with the addition of 3mg/kg furegrelate 3 times a day. The second group showed a 2.55-fold increase of the pulmonary vascular resistance index (PVRI) compared to the first group. The third group showed a reduction of 34% of the PVRI compared to the second group, and showed an improvement of the right ventricular hypertrophy.
When looking at arterial distensibility the second group showed a 33% reduction compared to the first group, the third group showed a reduction of only 20%. Furthermore, the muscularization of small pulmonary arteries was less prominent when comparing group 3 to group 2. Lastly, group 3 showed lower basal and vasodilator-induced transpulmonary pressures compared to group 2. In conclusion the inhibition of the enzyme thromboxane A2 synthase by furegrelate reduces hypoxia induced pulmonary arterial hypertension by preserving the pulmonary vasculature.
Furegrelate reduces renal vasoconstriction of angiotensin II, a blood pressure increasing hormone, in rats. It does this presumably by enhancing the formation of vasodilator prostaglandins. Inhibition of furegrelate induced a proapoptotic disposition of glioma cells in mice. In addition it increased the sensitivity to the chemotherapeutic agent 1,3-bis(2-chloroethyl)-1-nitrosourea. This significantly increased the survival time of intracerebral glioma-bearing mice.
References
Benzofurans
Carboxylic acids
3-Pyridyl compounds
Enzyme inhibitors | Furegrelate | [
"Chemistry"
] | 2,299 | [
"Carboxylic acids",
"Functional groups"
] |
68,394,738 | https://en.wikipedia.org/wiki/Thrust%20%28particle%20physics%29 | In high energy physics, thrust is a property, (one of the event shape observables) used to characterize the collision of high energy particles in a collider.
When two high energy particles collide, they typically produce jets of secondary particles. This happens when one or several quark-antiquark pairs are produced during the collision. Each colored quark/antiquark pair travels its separate way and subsequently hadronizes. Many new particles are created by the hadronization process and travel in approximately the same direction as the original pair. This set of particles constitutes a jet.
The thrust quantifies the coherence, or ″jettiness″ of the group of particles resulting from one collision. It is defined as:
,
where is the momentum of particle , and is a unit vector that maximizes and defines the thrust axis. The sum is over all the final particles resulting from the collision. In practice, the sum may be carried over the detected particles only.
The thrust is stable under collinear splitting of particles, and therefore it is a robust observable, largely insensitive to the details of the specific hadronization process.
References
Experimental particle physics
Quantum chromodynamics | Thrust (particle physics) | [
"Physics"
] | 249 | [
"Particle physics stubs",
"Experimental physics",
"Particle physics",
"Experimental particle physics"
] |
68,396,253 | https://en.wikipedia.org/wiki/NGC%207501 | NGC 7501 is an elliptical galaxy located in the constellation Pisces. It was discovered on September 2, 1864 by the astronomer Albert Marth. It is a member of the Pegasus II cluster of galaxies. A radio source has been detected within one minute of arc of the position of NGC 7501.
One supernova has been observed in NGC 3561: SN2021wyw (typeIa, mag. 19.5).
See also
List of NGC objects (7001–7840)
References
External links
Pisces (constellation)
7501
070619
+01-59-007
Elliptical galaxies
Discoveries by Albert Marth
18640902 | NGC 7501 | [
"Astronomy"
] | 137 | [
"Pisces (constellation)",
"Constellations"
] |
68,396,283 | https://en.wikipedia.org/wiki/Mizuike%20Pottery%20Kiln%20ruins | The is an archaeological site with the ruins of a large-scale Nara period pottery production site, located in the Myōjō neighborhood of the town of Meiwa, Mie in the Kansai region of Japan. It was designated a National Historic Site of Japan in 1970.
Overview
The Mizuike pottery production site is located on a fluvial terrace with an elevation of about ten meters, extending northward in the southern portion of the Ise Plain, approximately halfway between the cities of Matsusaka and Ise, and about four kilometers from the site of the Saiku. Per archaeological excavations starting in 1976, the site was found to contain the traces of three pit dwellings, four excavated pillar dwellings, 16 kilns for the firing of earthenware, 11 prehistoric storage pits, two clay pits, and one well. These features occupied a site on a gentle slope with a width of about 100 meters and length of about 200 meters, surrounded by a moat. The kilns were roughly triangular, with lengths of 2.6 to 4.2 meters and widths of 1.2 to 1.8 meters. The foundations of the buildings were no different from those found in ordinary settlements; however, there were a very large number of shards of Haji ware and a small amount of Sue ware found mixed with charcoal and ash in the soil around the kilns. These shards have been dated to the early Nara period, and the presence of small amounts of ash glazed pottery shards indicates that the site ay have been active through the late Nara period. Currently, the site is preserved as the . It is about a ten-minute walk from Myōjō Station on the Kintetsu Yamada Line.
See also
List of Historic Sites of Japan (Mie)
References
External links
Meiwa town home page
Ise Province
History of Mie Prefecture
Meiwa, Mie
Historic Sites of Japan
Japanese pottery kiln sites | Mizuike Pottery Kiln ruins | [
"Chemistry",
"Engineering"
] | 387 | [
"Kilns",
"Japanese pottery kiln sites"
] |
68,396,575 | https://en.wikipedia.org/wiki/Best%20Sex%20I%27ve%20Ever%20Had | "Best Sex I've Ever Had" is a headline that appeared on the front page of the New York Post on February 16, 1990. The headline is purportedly a quote from Marla Maples, who would become the second wife of businessman Donald Trump. The quote refers to Trump's supposed sexual prowess. Trump was married to Ivana Trump at the time of the headline; the couple's divorce was granted that year. The headline appeared during a media frenzy concerning the Trumps' marriage and his affair with Maples.
Background
At the time of the publication of the headline in 1990, the American businessman and property developer Donald Trump had been married to the Czech model Ivana Trump (née Zelníčková) since 1977. In December 1989, while on a family skiing holiday in Aspen, Colorado, Ivana and Marla Maples had encountered each other for the first time. Trump had secretly arranged for Maples, his mistress, to be present in Aspen at the time of his family's holiday. A February 11 article by Liz Smith in the New York Daily News had reported that Donald and Ivana Trump were no longer together.
In their 2017 biography of Trump, Trump Revealed, Michael Kranish and Marc Fisher detailed the media coverage of the breakdown of the couple's marriage, writing that in February 1990, despite the release of Nelson Mandela from prison and the bankruptcy of bankers Drexel Burnham Lambert, the Trumps' marriage "dominated the front pages of [New York City]'s tabloids" for "weeks".
Trump married Maples in 1993; the couple divorced in 1999.
Front page story
The New York Post and the New York Daily News were rivaling each other for stories on the couple's marriage at the time of the headline. Jill Brooke, the television and radio columnist for the New York Post at the time of the story, recalled in a 2018 article for The Hollywood Reporter that Trump had telephoned the editor of the New York Post, Jerry Nachman, in a rage as a result of an article in the Daily News by Liz Smith that he perceived as sympathetic to Ivana. In reference to his wife and Smith, Trump shouted "Those fucking bitches ... I want a front-page story tomorrow". The conversation was heard on speakerphone by Brooke. Nachman informed Trump that "Donald, you just don't demand a front-page story. There has to be a story" to which Trump replied that "For all the newspapers I've sold for you, you should give me one". After Trump asked Nachman how he could get a front-page story, Nachman told him that "murder, money or sex" would usually suffice as subject matters. Trump then told him "Marla says with me it's the best sex she's ever had". Nachman informed Trump that he needed corroboration for such a claim, at which point Trump shouted "Marla ... Didn't you say it's the best sex you ever had with me?". Brooke recalled that a "faint voice" could be heard replying "Yes, Donald" to Trump's question, and subsequent revelations that Trump adopted pseudonyms in conversations with journalists led Brooke to doubt whether the voice she heard in reply was actually Maples or Trump himself. Prior to the publication of Brooke's 2018 article, the New York Post reporter Bill Hoffmann had reported that the story had derived from his interview of two of Maples's friends from an acting class that she had been taking, and the friends had told Hoffmann that Maples had confided in them about her and Trump's love affair, and told them that Trump was "the best sex I've ever had".
Brooke felt the significance of the story stemmed from its novelty as prominent men "didn't discuss their sex lives on the record" at the time of the headline as it was a time "... before Facebook. This was before reality TV. This was when privacy mattered and oversharing was considered crass". The story was approved by Lou Colasuonno, the managing editor of the New York Post, who believed the story to be unlikely to be the target of a libel suit from Trump as "Donald will never complain about this one".
In February 1990 the Daily News ran Trump related stories for 12 successive days; with the New York Post running stories for eight days in succession. The Trump stories were described by Kranish and Fisher as having "reached their apex" when the "Best Sex I've Ever Had" headline was printed on the cover of the February 16 edition of the New York Post. The New York Post published 35 column inches on the Trumps' marital travails that day, with The New York Times publishing 49 inches, including detailed legal analysis of their marital split.
The front-page story that accompanied the headline was written by the New York Post reporter Bill Hoffmann. A photograph of Trump grinning was set alongside the article. The opening text of the article stated "We always knew Donald Trump was a tiger in the corporate board-room but now we know he's a wildcat in the bedroom too".
Impact
Trump met the New York magazine writer John Taylor on the day of the publication of the story; Taylor recalled that Trump was relaxed and was impressed by the level of media coverage that the breakup of his marriage was receiving. Trump told Taylor that he had "never seen anything like it in my life. One day it was eight pages in the tabloids. Even The New York Times is doing it ... One of the papers had twelve reporters on it". Taylor felt that Trump had understood that there was "no such thing as bad publicity" and Trump was "able to spin [the story] like he was this irresistible macho guy that was being chased by these blonde beauties all over town". New York reported that Hoffmann had received interview requests from ABC, CBS, NBC, Fox and CNN following his scoop.
Maples subsequently appeared on the episode "Marriage Most Foul" of the sitcom Designing Women as herself in 1991. The characters of the show asked Maples about the veracity of the quote in the headline, and she told them that it was untrue and that she had never said it.
Hilary Weaver, writing for Vanity Fair in 2018, described the quote as Maples's "most famous quote by far, and maybe the peak of her prominence in pop culture". Kranish and Fisher described the headline as a "tabloid classic". Barbara Res, an executive at The Trump Organization, recalled that Trump proudly showed her a copy of the New York Post on the day of its publication, and that he was in "a great mood ... a big smile plastered on his face". Res and other executives at the company thought the headline was "terrible", she personally worried about the effect of the headline on Trump's children, recalling that Trump had a "six-year-old at home. He's got a twelve-year-old that can read the papers ... we thought that was terrible. He thought it was the greatest thing". Donald and Ivana Trump's daughter, Ivanka, recalled in her 2009 book, The Trump Card, that "one idiot reporter" asked her if "Marla Maples's claims were true". Ivanka was 9 years old at the time of the headline and felt her family's life was "fair game, on full display ... It was so insane, so offensive, so upsetting, and there was no let-up".
Legacy
The headline gained renewed prominence in the wake of Trump's election to the presidency of the United States in 2016. In 2018, Maples denied that she had said the quote, telling reporters from the New York Posts Page Six gossip column that "I never said that, someone else said that ...[But] is it true? I'm not going to talk about that. The truth will come out, just not here". Maples winked at reporters after denying that she had given the quote.
In 2016 journalist Natasha Stoynoff accused Trump of forcibly kissing her in 2005 during a scheduled interview at Mar-a-Lago. After the alleged attack, Stoynoff said Trump referenced the New York Post cover and said, "You remember. Best sex I ever had."
References
1990 documents
1990 in New York City
February 1990 events in the United States
Cultural history of New York City
Cultural depictions of Donald Trump
Headlines
History of mass media in the United States
New York Post
1990 quotations
Works about sex | Best Sex I've Ever Had | [
"Biology"
] | 1,769 | [
"Works about sex",
"Behavior",
"Sexuality"
] |
68,396,728 | https://en.wikipedia.org/wiki/HAT-P-65 | HAT-P-65 is a faint star located in the equatorial constellation Equuleus. With an apparent magnitude of 13.16, it requires a telescope to be seen. The star is located away from Earth, but is drifting close with a radial velocity of -48 km/s.
Properties
HAT-P-65 has a similar spectral type to that of the Sun. However, it is 21% more massive, and 86% larger than the latter. HAT-P-65 is slightly hotter, with an effective temperature of 5,916 K compared to 5,778 K of the Sun. It also has a higher luminosity and metallicity, with an iron content 26% greater than the Sun.
Planetary system
In 2016, an inflated hot Jupiter was discovered orbiting the star in a tight 2 day orbit. As of 2019, the planet has been suffering orbital decay due to its proximity.
References
G-type subgiants
Planetary systems with one confirmed planet
Equuleus | HAT-P-65 | [
"Astronomy"
] | 202 | [
"Equuleus",
"Constellations"
] |
68,396,786 | https://en.wikipedia.org/wiki/3%20Body%20Problem%20%28TV%20series%29 | 3 Body Problem is an American science fiction television series created by David Benioff, D. B. Weiss and Alexander Woo and is the third streaming adaptation of the Chinese novel series Remembrance of Earth's Past written by former computer engineer Liu Cixin. Its name comes from the first volume, The Three-Body Problem, of the novel series and refers to a classical physics problem dealing with Newton's laws of motion and gravitation. Previous adaptations include the animated The Three-Body Problem in Minecraft (2014–2020) and the live-action Three-Body (2023), both of which were exclusively in Mandarin.
The series, set primarily in the United Kingdom and China, follows a diverse cast of scientists who all come into contact with an extraterrestrial civilization, leading to various threats and humanity-wide changes. It is Benioff and Weiss' first television project since the conclusion of their series Game of Thrones (2011–2019) and modifies part of the original works' Chinese setting to include foreign characters and locations.
The first season was released on Netflix on March 21, 2024, with eight episodes, and received positive reviews. In May 2024, the series was renewed for a second season; a third season was confirmed later the same month. The series received six Primetime Emmy Award nominations, including Outstanding Drama Series.
Premise
Ye Wenjie, a Chinese astrophysicist, runs into trouble with the authorities after witnessing her father's death during a struggle session in the Cultural Revolution. Due to her scientific background, she is sent to a secret military base racing against other countries to make first contact with aliens during the Cold War. While there, she makes a choice that impacts humanity's future. In present-day London, a series of mysterious suicides and science-averse phenomena lead a government investigator and a group of friends called the "Oxford Five" into a mystery of extraterrestrial origin.
Cast and characters
Main
Jovan Adepo as Dr. Saul Durand, a research assistant and member of the "Oxford Five"
John Bradley as Jack Rooney, an entrepreneur and member of the "Oxford Five"
Rosalind Chao and Zine Tseng as Dr. Ye Wenjie, an astrophysicist whose decisions as a young scientist threaten the survival of humanity. Chao portrays the character in the 2020s, while Tseng portrays a younger version in scenes set in the past.
Liam Cunningham as Thomas Wade, chief of the Secret Intelligence Service (MI6), who also heads the global Strategic Intelligence Agency
Eiza González as Dr. Augustina Salazar, a nanotechnologist and member of the "Oxford Five"
Jess Hong as Dr. Jin Cheng, a theoretical physicist and member of the "Oxford Five"
Marlo Kelly as Tatiana Haas, a fanatic member of a group of humans working for the San-Ti, an extraterrestrial civilization
Alex Sharp as Dr. Will Downing, a sixth form physics teacher and member of the "Oxford Five" who is diagnosed with stage 4 cancer early in the series
Sea Shimooka as "Sophon", a sophisticated intelligence platform used by the San-Ti to communicate with humanity
Saamer Usmani as Prithviraj Varma, a Royal Navy officer and Cheng's boyfriend
Benedict Wong as Clarence "Da" Shi, an MI6 officer working for Wade and the Strategic Intelligence Agency
Jonathan Pryce as Mike Evans, a friend of Ye Wenjie since the 1960s who shares her view that humanity should be eliminated, and has become a prominent member of the small group of humans working for the San-Ti
Recurring
Vedette Lim as Vera Ye
as Follower
Ben Schnetzer as young Mike Evans
John Dagleish as Felix
Gerard Monaco as Collins
Adrian Edmondson as Denys Porlock
CCH Pounder as Lillian Joseph, the Secretary-General of the United Nations
Lan Xiya as Tang Hongjing, a Red Guard
Josh Brener as Sebastian Kent
Guest
Mark Gatiss as Isaac Newton when shown in the alien San-Ti's advanced virtual reality system
Reece Shearsmith as Alan Turing
Conleth Hill as Pope Gregory XIII
Phil Wang as Aristotle
Naoko Mori as Marie Curie
Kevin Eldon as Thomas More
Jason Forbes as Omar Khayyam
Jim Howick as Harry
Nitin Ganatra as Ranjit Varma
Dustin Demri-Burns as Ted
Tom Wu as Count of The West
Guy Burnet as Rufus
Jake Tapper as himself
Bobak Ferdowsi as Flight director
Stacy Abalogun as Thelma
Episodes
Production
Development
It was announced in September 2020 that David Benioff and D.B. Weiss were developing a television adaptation of the novel at Netflix, with Alexander Woo co-writing alongside them. Benioff and Weiss have said they are prepared to adapt the whole trilogy, which they expect to require three or four seasons.
On December 25, 2020, Lin Qi, founder of Yoozoo Games and an executive producer on 3 Body Problem, died after ingesting a poisoned beverage, with four others becoming ill. An executive at Yoozoo Games, Xu Yao, was sentenced to death for murder in March 2024, the day after the series premiered on Netflix. Lin had purchased the rights to the book franchise and hired Xu Yao, a lawyer, in 2017, to manage the rights to Liu's novels; the poisonings were an attempt by Xu to take control of the subsidiary company that owned the rights to the series. On May 15, 2024, Netflix renewed the series for a second season. On May 31, 2024, Benioff, Weiss and Woo confirmed that the series was renewed for seasons 2–3 during the official Television Academy 3 Body Problem panel at the Netflix FYSEE space at Sunset Las Palmas in Los Angeles.
According to Benioff, he had already worked with UK-based staff for Game of Thrones and wanted to use them in this production, and Benioff stated that the need to coordinate among those staff influenced the choice of the UK as a setting in 3 Body Problem.
Casting
In August 2021, Eiza González entered negotiations to join the cast. The same month, Derek Tsang was hired to direct the pilot episode. González would be confirmed as joining the cast by that October, with additional castings including Benedict Wong, Tsai Chin, John Bradley, Liam Cunningham and Jovan Adepo. In June 2022, Jonathan Pryce, Rosalind Chao, Ben Schnetzer and Eve Ridley were added to cast.
Filming
Production on the series began on November 8, 2021, with principal photography taking place in the United Kingdom. Filming took place in London over a nine month shoot between October 2021 and mid 2022.
At Netflix's Tudum 2022 event, Alexander Woo, David Benioff, and D.B. Weiss announced that the production of the first season was completed.
Netflix reportedly spent $20million per episode, for a total budget of $160 million for the first season.
Release
3 Body Problem was released on March 21, 2024. A companion podcast to be hosted by Jason Concepcion and Maggie Aderin-Pocock was also announced alongside it. On January 10, 2024, SXSW Film & TV Festival announced 3 Body Problem as the Opening Night TV Premiere.
Reception
Critical response
The review aggregator Rotten Tomatoes reported a 79% approval rating with an average rating of 6.9/10, based on 112 critic reviews. The website's critics' consensus reads, "Tackling its ambitious source material with impressive gusto, 3 Body Problems first season proves a solid start that should leave sci-fi fans eager for more." Metacritic assigned it a score of 70 out of 100, based on 41 critics, indicating "generally favorable reviews".
Cindy White of The A.V. Club gave the series a B+ and said, "It may wear the garb of prestige television, but underneath its just a nerdy science-fiction show, with a healthy emphasis on the science." Reviewing the series for USA Today, Kelly Lawler gave a rating of 3/4 and wrote, "Benioff, Weiss and Woo took a book trilogy known more for its thought experiments in philosophy and theoretical physics than its plot and made a solid bit of hard sci-fi that is (mostly) accessible to more casual fans of the genre." Eric Deggans of NPR commented, "As the characters in 3 Body Problem lurch toward answers, we all get to bask in an ambitious narrative fueling an ultimately impressive tale. Just remember to be patient as the series sets the stage early on." Wenlei Ma of The Nightly described the series as "Ambitious, towering and crammed with big ideas about intellectual curiosity, exploration and our place in the universe while still managing to tell intimate stories about human relationships." Inkoo Kang of The New Yorker gave a positive review, writing "The Netflix adaptation of Liu Cixin's trilogy mixes heady theoretical questions with genuine spectacle and heart."
Ben Travers of IndieWire gave a critical review, writing that "3 Body Problem is a sprawling drag, at turns disorienting in its use of inconsistent CGI to convey the story's momentousness and aggravating in its approach to character development and existential quandaries. The plot is easy enough to track, but the relief of realizing you can keep up with this motley crew of scientist pals — as they try to figure out why so many of their peers are dying off — is short-lived." Charles Pulliam-Moore of The Verge gave a mixed review, writing that "though David Benioff, D. B. Weiss, and Alexander Woo's 3 Body Problem is impressive, it really feels like just an introduction to Cixin Liu's deeper ideas." He opined that future seasons could explore the world of Liu's later novels.
Response in China
3 Body Problem received a mixed response in China. While Netflix is blocked there, viewers can use VPNs to circumvent geo-restrictions, or view pirated versions. According to The Guardian, the 3 Body Problem hashtag had been read 2.3 billion times and discussed 1.424 million times on the Chinese social media platform Weibo. Viewers criticised the racebending and gender swapping of several protagonists, cultural appropriation, as well as the "dumbing-down" of concepts to appeal to non-Chinese audiences, and compared it unfavorably to the 2023 Chinese television adaptation, which received much critical acclaim there. The Chinese film review website Mtszimu praised the Netflix adaptation as "not only a new interpretation of Liu Cixin's original work but also an important contribution to global science-fiction literature". China Military Online, the official newspaper of the People's Liberation Army, criticized the series for retaining Chinese villains while doing away with portrayals of the country's modern development.
In response to social media criticism about racebending, cast member Benedict Wong said that Liu had given the showrunners his blessing to move the story towards a global one. Wong also cited the presence of several Asian cast members including himself, Jess Hong, Rosalind Chao and Zine Tseng. Hong and Chao also said that the Netflix adaptation preserved the novel's depiction of the Cultural Revolution and its legacy. Hong said that the adaptation sought to "globalize a story that was very heavily Eastern-focused into a Western perspective, a global perspective. Because, we're all from different countries, for the actors, you get to pull in all of these brilliant storylines into one emotional core, which is quite brilliant."
Aja Romano of Vox suggested that the media exaggerated Chinese social media nationalistic outrage against the Netflix show. They found that the Chinese audience "praising the show and criticizing it in equal parts", and shared similar critical commentary to the ones from the Western audience, underscoring that criticism of the show is universal.
The original author, Liu Cixin, commented on the series, saying, "I enjoyed the part of the series where many characters were added, and their relationships were explored. However, it was strange how all these characters seemed to know each other already. Fighting against the alien invasion should be a collective effort of all humanity, but instead, it was depicted as if a group of classmates were drafted to fight against the aliens."
Depiction and interpretation
3 Body Problem contains a realistic depiction of the struggle session during the Chinese Cultural Revolution, which was met with divided opinions in China and the United States. In an interview, David Benioff told The Hollywood Reporter the show "isn't a commentary on cancel culture", but agreed the fiction has parallels with the contemporary sociopolitical landscape. Derek Tsang, the director of the first two episodes, was recruited due to his Chinese background to ensure the authenticity of the Cultural Revolution period. Tsang explained that the goal of the episode was to convince the audience to empathize with the protagonist, Ye Wenjie, and understand her motivation and position in the story.
Joel Stein of The Hollywood Reporter noted the Cultural Revolution scene sparked split interpretations from American liberal and conservative critics, with the conservative side focusing on its warning against wokeness and the "far-left agenda", including gender theories, whereas the liberal viewers found the scenes as a warning to conservative-led populism and faith-based agendas.
Accolades
See also
Three-body problem – a problem of mathematics and physics, as well as classical and quantum mechanics, regarding any three objects and the gravitational effects they may have on one another.
References
External links
2020s American drama television series
2020s American mystery television series
2020s American science fiction television series
2024 American television series debuts
Television about alien invasions
American fantasy drama television series
American thriller television series
American English-language television shows
Cultural depictions of Alan Turing
Cultural depictions of Isaac Newton
Cultural depictions of Marie Curie
Cultural depictions of Omar Khayyam
Cultural depictions of Thomas More
Netflix television dramas
Television series about the Cultural Revolution
Television series created by D. B. Weiss
Television series created by David Benioff
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Adaptations of works by Liu Cixin | 3 Body Problem (TV series) | [
"Astronomy"
] | 2,934 | [
"Cultural depictions of Isaac Newton",
"Cultural depictions of Omar Khayyam",
"Cultural depictions of astronomers"
] |
68,396,815 | https://en.wikipedia.org/wiki/A.%20Murat%20Eren | A. Murat Eren (Meren) is a computer scientist known for his work on microbial ecology and developing novel, open-source, computational tools for analysis of large data sets.
Early life and education
Eren grew up in the Barhal Valley in Turkey and studied cryptography as an undergraduate at Canakkale Onsekiz Mart Universitesi where he earned a B.S. in 2002. He moved to the United States and started his Ph.D. at the University of New Orleans. While working at the Children's Hospital of New Orleans, Eren was introduced to microbiology by Michael Ferris. In 2011 Eren completed his Ph.D.; his dissertation was titled Assessing microbial diversity through nucleotide variation.
Career and research
Eren's Ph.D. research involved developing oligotyping, a computational method to examine the diversity of microorganisms within high throughput sequencing datasets. Following his Ph.D., Eren joined the Marine Biological Laboratory as a postdoctoral scientist, during which he applied oligotyping to microbes that live in the human genitourinary tract, oral cavity, and sewage. In 2015 he joined the University of Chicago as an assistant professor, where he started using metagenomics to investigate the ecology and evolution of microbes found in the human gut, human mouth, and surface ocean. In 2022, Eren was appointed Professor of Ecosystem Data Science at the University of Oldenburg and the Alfred Wegener Institute for Polar and Marine Research.
Eren is an advocate of open-source software and leads the community development of anvi'o, a platform to allow analysis and visualization of large datasets.
Selected publications
Awards and honors
Alfred P. Sloan Foundation Research Fellowship in Ocean Sciences (2020)
American Society for Microbiology Award for Early Career Environmental Research (2021)
Research Parasite Award Sustained Parasitism (2022)
References
External links
University of Chicago faculty
University of New Orleans alumni
Çanakkale Onsekiz Mart University alumni
Living people
Turkish computer scientists
Ecologists
Free software programmers
1980 births | A. Murat Eren | [
"Environmental_science"
] | 428 | [
"Ecologists",
"Environmental scientists"
] |
68,398,412 | https://en.wikipedia.org/wiki/Billet%20%28wood%29 | A billet was a specific and standardised form of wood fuel of significant importance in the traditional pre–fossil fuel economy.
The term could also be applied to a cudgel.
Nature and use
Billets were especially designed for burning on open hearth fires, often in conjunction with spits.
Measurements and cost
The 16th C standardised a billet as three foot four inches in length, and ten inches around.
A century later, Anthony A Wood recorded a load of billet wood as costing 12s 6d; while extravagance consisted of "burning in one yeare threescore pounds worth of the choicest billet".
Literary references
The William Shakespeare play Measure for Measure contains the phrase "beat out my brains with billets".
See also
Bavin (wood)
Fascine
billet (heraldry)
References
External links
Definition of billet
Firewood
Fuels
Wood fuel | Billet (wood) | [
"Chemistry"
] | 182 | [
"Fuels",
"Chemical energy sources"
] |
68,400,700 | https://en.wikipedia.org/wiki/Conopharyngine | Conopharyngine is the major alkaloid present in the leaves and stem-bark of Tabernaemontana pachysiphon and Conopharyngia durissima. It is closely related voacangine and coronaridine. Conopharyngine pseudoindoxyl, a derivative of it, is also found in the same plant Tabernaemontana pachysiphon.
Pharmacology
It possess central nervous system stimulant activity and produces bradycardia and hypotension in cats. It has weak acetylcholinesterase inhibitory activity and significantly increases hexobarbitone induced sleeping time.
Toxicity
It has low intravenous toxicity in mice (LD50 = 143 mg/kg).
See also
Ibogaline
References
Alkaloids found in Iboga
Methoxy compounds
Heterocyclic compounds with 5 rings
Methyl esters
Nitrogen heterocycles
Tryptamine alkaloids
Catechol ethers | Conopharyngine | [
"Chemistry"
] | 207 | [
"Tryptamine alkaloids",
"Alkaloids by chemical classification"
] |
68,401,732 | https://en.wikipedia.org/wiki/Homey%20%28smart%20hub%29 | Homey is a smart home hub manufactured by the Dutch company Athom B.V.
Homey has a mobile & web app interface with an open API that allows third-party developers to add support for their products in Homey. Like other smart home hubs, the purpose of Homey is to act as a central point of configuration, control and monitoring of components in a smart home. An automatic control flow is nicknamed a "Flow" in the Homey app.
History
Homey was originally started as a Kickstarter project in May 2014 by Emile Nijssen and Stefan Witkamp, and the company Athom B.V. was founded to take care of the development. In 2015, private investors invested 1 million euro in the company.
Models
Homey (2016)
In 2016, the first version of the Homey was released after having started as a Kickstarter project in 2014. The first generation of Homey had a built-in microphone and software for speech recognition, and as such could be regarded as both a smart speaker and a smart home hub. It had support for connecting over Wi-Fi, Bluetooth, ZigBee, Z-Wave, 433 MHz, 868 MHz and infrared light.
Homey (2019)
In 2019, the second generation of Homey was released. Notable hardware changes include removal of the near-field communication module due to little use, as well as removal of the microphone because Homey had deemed it to not be good enough to function as planned.
The software was also updated to version 2.0, and older equipment could also be upgraded to this version. Some of the changes in the software was a more complete mobile app, while support for the desktop application was removed. Support was added for lighting control using KNX. The Homey second generation had a hardware with 512 MB random-access memory and a single core central processing unit.
Homey Pro (2019)
Homey Pro was also launched in 2019 at the same time as the second generation of the Homey base model, but the Pro edition had a twice as powerful hardware with 1 GB of random-access memory and a dual core processor.
Homey Bridge (2022)
Homey Bridge was announced during a livestream on September 7, 2021, as an optional wireless antenna for the then-introduced cloud-service.
Supported technologies are Wi-Fi, Bluetooth Low Energy, Zigbee, Z-Wave, 433 MHz and Infrared.
Homey Pro (2023)
A new generation Homey Pro was announced during a livestream on October 12, 2022, and started shipping in Q1 2023.
Notable changes are a new flat design, similar to Homey Bridge, based on a Raspberry Pi Compute Module 4, shipping with a quad core processor, 2 GB of random-access memory and 8 GB flash storage.
Supported technologies are Wi-Fi, Bluetooth Low Energy, Zigbee, Z-Wave, 433 MHz, Infrared, Matter and Thread.
Supported devices
The Homey software has partial support for integration with selected components from other smart home systems, such as Philips Hue, IKEA, Google Nest, Chromecast, Logitech Harmony, Spotify Connect and Sonos.
Homey claims to support over 50 000 different devices from over 1000 brands.
See also
Home Assistant
Google Nest
Apple HomePod
Internet of things
References
Smart home hubs | Homey (smart hub) | [
"Technology"
] | 689 | [
"Home automation",
"Smart home hubs"
] |
68,402,203 | https://en.wikipedia.org/wiki/Global%20Journal%20of%20Environmental%20Science%20and%20Management | The Global Journal of Environmental Science and Management is a quarterly peer-reviewed open access academic journal covering environmental management. It was established in 2015. The founding and current editor-in-chief is Jafar Nouri (Tehran University of Medical Sciences).
Abstracting and indexing
The journal is indexed and abstracted in the following bibliographic databases:
CAB Abstracts
EBSCO databases
Emerging Sources Citation Index
Scopus
References
External links
Academic journals established in 2015
Quarterly journals
Creative Commons Attribution-licensed journals
Environmental science journals
English-language journals | Global Journal of Environmental Science and Management | [
"Environmental_science"
] | 110 | [
"Environmental science journals"
] |
68,402,408 | https://en.wikipedia.org/wiki/Smart%20home%20hub | A smart home hub, sometimes also referred to as a "smart hub", "gateway'", "bridge", "controller" or "coordinator", is a control center/centre for a smart home, and enables the components of a smart home to communicate and respond to each other via communication through a central point. The smart home hub can consist of dedicated computer appliance, software appliance, or software running on computer hardware, and makes it possible to gather configuration, automation and monitoring of a smart house by communicating and controlling different smart devices that consist of for example home appliances, sensors and relays or robots, many of which are commonly categorized under Internet of things.
A smart home can contain one, several, or even no smart home hubs. When using several smart home hubs it is sometimes possible to connect them to each other. Some smart home hubs support a wider selection of components, while others are more specialized for controlling products within certain product groups or using certain wireless technologies (e.g. Wi-Fi, Bluetooth, Z-Wave, and/or Zigbee).
A smart speaker with a virtual assistant can often be used for speech input to a smart home hub.
Open or closed source code
Smart home hubs can have software with open source code or use proprietary software with closed source code, and independently of this the application programming interface can be public or closed. Some smart home hubs must run on proprietary hardware, while others (like for example Home Assistant) can be installed on generic hardware (like for example a laptop or single-board computer with Linux).
Examples of commercial smart home hubs
Some examples of smart home hubs with closed source code are:
Logitech Harmony Hub
SmartThings Hub
Google Nest Hub
Amazon Echo Show and Amazon Echo Plus which both integrates a Zigbee hub.
Apple HomePod
Some examples of smart home hubs based on free and open-source software are:
Home Assistant
OpenHAB
Some examples of smart home hubs with closed source code, but an open application programming interface are:
Homey
Communication protocols
Various communication protocols can be used between smart home hubs and smart house components. The protocols can be grouped into wired and wireless technologies.
Wireless protocols
Some examples of wireless protocols commonly used in smart home hubs are:
2,45 Ghz (WiFi, Bluetooth, Zigbee, Thread, Matter)
Z-Wave (868 Mhz)
RF 868 (868 Mhz, various protocols)
RF 433 (433 Mhz, various protocols)
Infrared light (430 THz; 697 nm)
Wired protocols
There are several cabled bus systems, some of which are built directly into electric panels. Some examples of wired protocols commonly used in smart home hubs are:
DALI, open standard for network-based lighting control in buildings, well suited for dimming.
KNX, older and well-established open standard for network-based control of lighting, sensors, HVAC, etc. in buildings. There is also a wireless extension of KNX called KNX-RF.
DMX, a standard for control of stage lighting, smoke machines and more, but also used to a certain extent for home automation due to the widespread use in professional stage equipment and good availability on the market
X10, widespread in older home automation equipment in the USA, but only used to a small extent in new installations.
LonWorks, an open standard for networking platforms used for control applications of lighting and HVAC.
MQTT, an open network protocol for machine to machine communication, particularly used for transmission of telemetry data in Internet of things components.
BACnet, an open protocol (ISO 16484-5) for information exchange between building automation systems, regardless of the particular building service they perform. Designed for applications such as automation and control of heating, ventilating, and air-conditioning control (HVAC), lighting control, access control, fire detection systems, and associated equipment.
Modbus, an openly published and royalty free data communications protocol, especially popular in industrial environments.
Meter-Bus (M-Bus), an open standard for remote reading of consumption meters, e.g. water, gas or electricity meters.
See also
List of home automation software
Smart speaker
Matter
References
Home automation | Smart home hub | [
"Technology"
] | 871 | [
"Home automation"
] |
68,402,947 | https://en.wikipedia.org/wiki/Event%20shape%20observables | In high energy physics, event shapes observables are quantities used to characterize the geometry of the outcome of a collision between high energy particles in a collider. Specifically, event shapes observables quantify the general pattern traced by the trajectories of the particles resulting from the collision.
The most common event shape observables include:
The sphericity;
The aplanarity;
The thrust.
The C-parameter;
The jet broadening.
References
Experimental particle physics | Event shape observables | [
"Physics"
] | 104 | [
"Particle physics stubs",
"Experimental physics",
"Particle physics",
"Experimental particle physics"
] |
68,403,092 | https://en.wikipedia.org/wiki/Shoe%20dryer | A shoe dryer or boot dryer is a machine used for drying shoes, and usually functions by blowing air on the inside of the shoes. The airflow causes the shoes to dry faster. The air can be heated for even faster drying, and these are the most common types. Shoes dryers can be especially useful for people who often have wet shoes, such as families with small children or people who often hike outdoor in the nature, or for ski boots which often are moist after use. Many shoes dryers have a timer which shuts off the dryer after some time. There are also shoe dryers which instead use a heated grate which the shoes are placed on top of, and which do not blow air.
History
Several patents have been awarded for shoe dryers, with some of the oldest dating back to 1963.
Noise
Many fan-driven shoe dryers emit bothersome noise during use. In a test from 2019, the most silent model was measured at 45 decibel (dB), while the other models were measured at 50 and 57 dB. In 2022, another model was measured at 56 dB in "tornado" mode and 29 dB in "whisper" mode, and in 2023 another variant of the same dryer was measured at 72 dB. It was also commented that the higher pitch of the said models noise could contribute to it being perceived as more intense and bothersome.
Air flow
The volumetric flow rate, i.e. the amount of air that is moved, is an important measure of fan-based shoe dryers. For example, a model tested in 2023 was stated to have a volume flow of 12 cubic meters per hour (m³/h), which corresponds to 12 000 liters per hour or just over 3 liters of air per second. Larger diameters of tubing and fans are beneficial for increased volumetric flow, and also results in lower air speed and thus less noise.
Heated air
Shoe dryers with a fan often emit slightly lukewarm or warm air. In a test from 2019, one of the models was rated at a power of 350 watt, of which 30 W was utilized as fan power and the remaining around 320 W were used for heating. Another model in the test had two temperature settings for choosing between 40 °C and 55 °C air temperature. A model tested in 2023 had settings for blowing air at room temperature, or heated air at 37, 45 or 60 degrees Celsius.
Not all shoes can withstand heated drying. Using high heat can put wear on shoes made of certain materials, and for example the use of a tumble dryer, heating cables or heating cabinet can lead to leather shoes cracking.
Fire hazard
Shoe dryers with heating can be a fire hazard if left on for too long, as with any heating appliance, and should therefore be used under supervision.
See also
Dehumidifier
Drying cabinet
Drying room
References
Home appliances | Shoe dryer | [
"Physics",
"Technology"
] | 594 | [
"Physical systems",
"Machines",
"Home appliances"
] |
68,403,687 | https://en.wikipedia.org/wiki/Luca%20Comai | Luca Comai is an Italian plant biologist whose work has focused on trait discovery for improving agricultural crops and on developing protocols and systems for identifying new genes and mutations in plants. Through his work at Calgene, Comai was one of the first discoverers of the glyphosate resistance gene and is considered a pioneer in the field of plant biotechnology research.
His research since then has focused on developing the Targeting Induced Local Lesions in Genomes (TILLING) protocol that allows for new mutations and traits to be quickly identified within a target plant species through genome and sequence analysis. He has received a number of research and teaching awards, along with being named a Fellow for the American Association for the Advancement of Science (AAAS). In 2023, he was elected to the National Academy of Sciences.
Education
Comai received his bachelor's degree in agricultural sciences from the University of Bologna in 1976 and his Master's degree in the field of plant pathology in 1978 from Washington State University. He then went on to earn his Ph.D. in plant pathology from the University of California, Davis and completed a postdoc at the same university. His doctoral thesis was on the subject of how Indole-3-acetic acid (IAA) is produced in bacteria and how this genetic function was homologous to the plant hormone production of the same name in plants that is encoded in the genome as T-DNA from Agrobacterium.
Career
Calgene researcher
Comai first applied for a teaching position at the University of California, Riverside in January 1981. But when this position wasn't offered to him, he instead joined the biotech company Calgene in the latter half of 1981 during its initial opening period. While he had been attempting to get support among the Riverside faculty for his application, he had been informed of the properties of glyphosate and its specific targeting of the EPSP synthase enzyme. He proposed to Calgene's science board that they try to develop a plant gene mutation that changed the shape of EPSP synthase so that glyphosate would be unable to bind to it. His suggestion was rejected due to glyphosate being a product produced by another company, but he decided to work on the gene mutation on his own time. Using Salmonella, he used random mutagenesis and subsequent application of glyphosate to try and stumble across the EPSP synthase mutation he was seeking and he succeeded.
In 1982, Comai presented his glyphosate tolerance mutation to a fellow scientist, Steve Rogers, who worked at Monsanto and demonstrated that he had made a superior form of the resistance gene than the one Monsanto had been working on. Though it was still not good enough for agricultural production and Comai continued his independent work. He published a paper in the journal Nature in October 1985 describing how he and his colleagues at Calgene had created glyphosate-resistant plants using the gene mutation Comai had found years earlier. This outcompeting of Monsanto's flagship product created a strong sense of rivalry with Calgene and subsequent layoffs at Monsanto at the end of 1985.
University of Washington and UC Davis professor
First becoming a professor at the University of Washington in 1990, Comai's lab focused on the development of improved agricultural genetic traits by using the model organism Arabidopsis thaliana to co-develop what was referred to as the TILLING protocol. This system included developing gene models and inbred lines, including an expanded EcoTILLING protocol developed in 2004, to compare differences in these plant lines to the reference genome and isolate new mutations and traits for further research. He would later lead the TILLING Core Service Facility at UC Davis that continued developing a genetic analysis platform called "TILLING-by-Sequencing" that would be used on not just Arabidopsis, but was expanded to also include Camelina, tomato, rice, and wheat. An award sponsorship of $489,000 was given to Comai's lab in 2014 from a joint donation of three companies in order to sponsor the further use of TILLING in current tomato cultivar populations.
Comai joined UC Davis in 2006 with his lab's research focusing on glyphosate resistance, functional genomics, and epigenetics, along with general mutational trait research. He is also well known for his work as a teacher of the "BIS 101" undergraduate genetics course and his use of whiteboard writing and his co-produced video series alongside the university. A collaboration between Comai's lab and Kyoto University in 2014 on the genetic sex reproduction of the persimmon species Diospyros lotus found through investigating the genomes of several dozen male and female plants the specific genes involved in their sex determination. As these persimmons are among the few plants exhibiting dioecy, this discovery opened up agricultural opportunities for trait improvement and the research received significant media interest.
Awards and honors
Comai was named a Fellow of the (AAAS) in 2012. The Distinguished Research Award was given to Comai in 2015 from the College of Biological Sciences at UC Davis thanks to his accomplishments in the TILLING protocol. In 2016, Comai was awarded with a Institute Honorary Fellowship from the University of Bologna for his work on the genetic improvement of plants. He was also given a Faculty Teaching Award from the College of Biological Sciences at UC Davis in 2017 for his innovations in teaching and his encouragement of high motivation among his students. The 2017 "Innovation Prize for Agricultural Technology" from the American Society of Plant Biologists was presented to Comai for his work on TILLING protocols and plant trait development.
References
External links
Author profile on Google Scholar
Phytopathologists
Biotechnologists
Italian biologists
University of Bologna alumni
Washington State University alumni
Washington State University faculty
University of California, Davis alumni
University of California, Davis faculty
Fellows of the American Association for the Advancement of Science
Year of birth missing (living people)
Living people
Members of the United States National Academy of Sciences | Luca Comai | [
"Biology"
] | 1,231 | [
"Biotechnologists"
] |
74,216,190 | https://en.wikipedia.org/wiki/Zhu%20algebra | In mathematics, the Zhu algebra and the closely related C2-algebra, introduced by Yongchang Zhu in his PhD thesis, are two associative algebras canonically constructed from a given vertex operator algebra. Many important representation theoretic properties of the vertex algebra are logically related to properties of its Zhu algebra or C2-algebra.
Definitions
Let be a graded vertex operator algebra with and let be the vertex operator associated to Define to be the subspace spanned by elements of the form for An element is homogeneous with if There are two binary operations on defined byfor homogeneous elements and extended linearly to all of . Define to be the span of all elements .
The algebra with the binary operation induced by is an associative algebra called the Zhu algebra of .
The algebra with multiplication is called the C2-algebra of .
Main properties
The multiplication of the C2-algebra is commutative and the additional binary operation is a Poisson bracket on which gives the C2-algebra the structure of a Poisson algebra.
(Zhu's C2-cofiniteness condition) If is finite dimensional then is said to be C2-cofinite. There are two main representation theoretic properties related to C2-cofiniteness. A vertex operator algebra is rational if the category of admissible modules is semisimple and there are only finitely many irreducibles. It was conjectured that rationality is equivalent to C2-cofiniteness and a stronger condition regularity, however this was disproved in 2007 by Adamovic and Milas who showed that the triplet vertex operator algebra is C2-cofinite but not rational. Various weaker versions of this conjecture are known, including that regularity implies C2-cofiniteness and that for C2-cofinite the conditions of rationality and regularity are equivalent. This conjecture is a vertex algebras analogue of Cartan's criterion for semisimplicity in the theory of Lie algebras because it relates a structural property of the algebra to the semisimplicity of its representation category.
The grading on induces a filtration where so that There is a surjective morphism of Poisson algebras .
Associated variety
Because the C2-algebra is a commutative algebra it may be studied using the language of algebraic geometry. The associated scheme and associated variety of are defined to be which are an affine scheme an affine algebraic variety respectively. Moreover, since acts as a derivation on there is an action of on the associated scheme making a conical Poisson scheme and a conical Poisson variety. In this language, C2-cofiniteness is equivalent to the property that is a point.
Example: If is the affine W-algebra associated to affine Lie algebra at level and nilpotent element then is the Slodowy slice through .
References
Algebras
Algebraic geometry | Zhu algebra | [
"Mathematics"
] | 586 | [
"Mathematical structures",
"Algebras",
"Fields of abstract algebra",
"Algebraic structures",
"Algebraic geometry"
] |
74,216,929 | https://en.wikipedia.org/wiki/Dithiobutylamine | Dithiobutylamine (DTBA) is a reducing agent intended as an alternative for DTT in biochemical uses. It was designed to be easily synthesized in non-racemic form, to have a lower pKa (allowing more effective reduction at neutral pH), and to have a low disulfide E°′ reduction potential. It was rationally designed & reported in 2012. It is commercially available.
See also
Dithiothreitol (DTT)
2-Mercaptoethanol (BME)
TCEP
References
Thiols
Reducing agents | Dithiobutylamine | [
"Chemistry"
] | 119 | [
"Redox",
"Thiols",
"Reducing agents",
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
74,219,124 | https://en.wikipedia.org/wiki/Madeira%20finch | The Madeira finch (Goniaphea leucocephala) is a hypothetical species of recently extinct small passerine bird from the Portuguese archipelago of Madeira, which is bigeographically part of Macaronesia. It should not be confused with the extant Madeiran chaffinch (Fringilla maderensis).
Discovery
The only known account is the 1823 description and illustration of a bird by British author Thomas Edward Bowdich, published by his widow Sarah Bowdich Lee in the 1825 book Excursions in Madeira and Porto Santo, during the autumn of 1823, while on his third voyage to Africa. No remains of this bird survive; if collected it was probably lost while en route to Europe, as it happened to most of Bowdich's specimens.
Description
Bowdich's original text and footnote read:
Taxonomy
Bowdich's concern that G. leucocephala might not be native to Madeira was echoed by other authors that placed it on the New World genus Passerina rather than the Fringillidae sensu stricto. However this was rejected as implausible by Harald Pieper in 1985. Pieper found abundant subfossil remains of fringillids in Madeira, which included at least one clearly new species of the genus Acanthis or a close relative. But despite noting Bowdich's account and supporting its interpretation as belonging to an endemic, recently extinct fringillid from Madeira, he refrained from assigning any remains to this species.
Extinction
No similar bird was seen or described again, so the species must have disappeared before Richard Thomas Lowe surveyed Madeira and Porto Santo in 1853. It could have disappeared due to human alteration of its habitat or introduced predators. The natural vegetation of the islands was considerably altered after settlement began in 1420, particularly in the lowlands, which caused the extinction of several bird species including flightless rails and quails. By 1859, Charles Darwin noted that the islands were strangely devoid of endemic species. Pieper, who studied pre-settlement bird remains from Madeira and Porto Santo in the 1980s, found that many actually belonged to extinct endemics, while songbirds presently common in Madeira like the common linnet and European goldfinch were absent. This supports the idea that the native avifauna of the islands largely became extinct as a result of human activity and was replaced by species from the continent.
References
Birds of Madeira
Holocene extinctions
Extinct birds of Atlantic islands
Hypothetical species
Finches | Madeira finch | [
"Biology"
] | 506 | [
"Biological hypotheses",
"Controversial taxa",
"Hypothetical species"
] |
74,223,180 | https://en.wikipedia.org/wiki/Medicinal%20Research%20Reviews | Medicinal Research Reviews is a bimonthly peer-reviewed scientific journal that publishes reviews on topics related to medicinal research. It is published by Wiley and was established in 1980. The editor-in-chief is Amanda E. Hargrove (Duke University).
The journal publishes critical reviews of topics include pathophysiology, genomics and proteomics, and clinical characteristics of important drugs.
Abstracting and indexing
The journal is abstracted and indexed in:
According to the Journal Citation Reports, the journal has a 2021 impact factor of 12.388.
References
External links
English-language journals
Wiley (publisher) academic journals
Academic journals established in 1980
Bimonthly journals
Medicinal chemistry journals | Medicinal Research Reviews | [
"Chemistry"
] | 141 | [
"Biochemistry stubs",
"Medicinal chemistry stubs",
"Medicinal chemistry journals",
"Medicinal chemistry"
] |
74,225,895 | https://en.wikipedia.org/wiki/NGC%203583 | NGC 3583 is a barred spiral galaxy located in the constellation Ursa Major. It is located at a distance of circa 90 million light years from Earth, which, given its apparent dimensions, means that NGC 3583 is about 85,000 light years across. It was discovered by William Herschel on February 5, 1788.
NGC 3585 has a bright nucleus and an elliptical bulge. It has a prominent bar which is about 30 arcseconds long. The spiral arms start approximately at the radius of the end of the bar. One arm emanates from northwest edge of the bulge. At its start is quite diffuse but after passing near the bar becomes better defined. After reaching the southeast part of the galaxy it starts to fade. The other arm emanates from the southeast end of the bar. It appears to branch after passing from the other side of the bar, with the two branches running parallelly.
The galaxy has many HII regions. The star formation rate in the galaxy based on the infrared luminosity is 9.8 per year.
NGC 3583 is the foremost galaxy in the NGC 3583 galaxy group. Also member of the group is the galaxy NGC 3595, while a bit farther away lies NGC 3614 and its group. NGC 3583 forms a pair with a small elliptical galaxy, which lies 0.9 arcminutes from NGC 3583. Barred spiral galaxy NGC 3577 lies at a projected distance of 5 arcminutes.
Supernovae
Two supernovae have been observed in NGC 3583:
SN 1975P (type unknown, mag. 15) was discovered by Charles Kowal on 1 December 1975.
ASASSN-15so (type Ia supernova, mag. 15.1) was discovered by ASAS-SN on 8 November 2015, about 10 days before maximum light.
See also
List of NGC objects (3001–4000)
References
External links
Barred spiral galaxies
Ursa Major
3583
06778
034232
Astronomical objects discovered in 1788
Discoveries by William Herschel | NGC 3583 | [
"Astronomy"
] | 424 | [
"Ursa Major",
"Constellations"
] |
74,227,856 | https://en.wikipedia.org/wiki/ARJ%20Home%20Appliances%20Company | Arj Home Appliance Company () is a white goods manufacturer in Iran. It was founded by Khalil Arjomand in 1937 as a small workshop in Tehran, Iran with eight employees. It started by producing water coolers and refrigerators. It later expanded its production line to include gas heaters, washing machines, freezers, and other devices.
History
The company originally began with a small factory producing metal products. Gradually, it broadened its range of products, increasing the number of employees to eight in the 1940s. With the expansion, the brand moved to Tehran-Karaj Road – the main industrial area to the west of the Iranian capital – where it broadened its range to include several household appliances.
However, in 1979, as with many of its competitors, Arj was nationalized due to the new revolutionary government's dislike of large businesses not under national control. By 1995 the majority of its shares were then sold off to Iran's largest state bank, Melli (National) Bank, which sold them on to different private shareholders.
Bankrupt and closure
Arj had been closed since 1995. As a result of increasing competition from foreign brands and financial problems, the company declared bankruptcy in the fiscal year 2016–17.
Arj officially closed in 2016 due to escalating production problems. The main reasons leading to its closure may have been:
Public administration and inefficient management policies
Exchange rate fluctuations causing a sharp rise in imports
Lack of strategy
Old technology and poor quality products
Revival of the brand
The Ministry of Industry decided to hold talks with multinational conglomerate corporation General Electric (GE), the American multinational manufacturer and marketer of home appliances Whirlpool Corporation, and the Italian Ariston Thermo Group to revive and update the named Iranian companies like Arj and others.
References
Iranian brands | ARJ Home Appliances Company | [
"Physics",
"Technology"
] | 371 | [
"Physical systems",
"Machines",
"Home appliances"
] |
74,228,604 | https://en.wikipedia.org/wiki/Damper%20winding | The damper winding (also amortisseur winding) is a squirrel-cage-like winding on the rotor of a typical synchronous electric machine. It is used to dampen the transient oscillations and facilitate the start-up operation.
Since the design of a damper winding is similar to that of a asynchronous motor, the winding technically enables the direct-on-line start and can even be used for the motor operation in the asynchronous mode.
Originally the damper winding was invented by Maurice Leblanc in France and Benjamin G. Lamme in the US to deal with the problem of hunting oscillations due to the early generators being driven by the directly connected steam engines with their pulsating torque. In the modern designs the generators are driven by turbines and the issue of hunting is less important, although pulsating torque is still encountered by motors, for example, while driving the piston compressors.
The construction of the damper windings is complex and largely based on empirical knowledge. A typical damper winding consists of short-circuit bars that in the machines with cylindrical rotors share the slots with the field windings, and in the case of salient pole rotors are located in the dedicated slots on the surfaces of pole shoes. There are no bars in the quadrature axis area of the salient pole machines. The bars are terminated on rings or plates encircling the rotor.
References
Sources
Electrical engineering
Electromagnetic coils | Damper winding | [
"Engineering"
] | 307 | [
"Electrical engineering"
] |
74,231,478 | https://en.wikipedia.org/wiki/Huanjing%20bunao | ( or coitus reservatus) is a Daoist sexual practice and yangsheng ("nourishing life") method aimed at maintaining arousal for an extended plateau phase while avoiding orgasm. According to this practice, retaining unejaculated (, "semen; [medical] essence of life") supposedly allows it to rise through the spine to nourish the brain and enhance overall well-being. Daoist adepts have been exploring various methods to avoid ejaculation for more than two thousand years. These range from meditative approaches involving breath-control or visualization to manual techniques such as pressing the perineum or squeezing the urethra.
In traditional Chinese medical theory, the (, "kidney") organ system was considered the reservoir for semen, bone marrow, brain matter, and other bodily fluids. However, in actual fact, huanjing bunao often leads to retrograde ejaculation, which redirects the semen into the bladder, from where it is expelled along with urine. Anatomically speaking, circulating seminal fluid or "seminal essence" throughout the body is impossible. While this ancient Chinese practice has historical and sexological significance, its physiological effects do not align with the traditional beliefs surrounding it.
On the other hand, in some more in-depth interpretations of Taoism, the idea that "the seed would travel up the spine" is to be understood allegorically. Sexual energy is transformed into a more subtle circulating form (from jing to chi). Chi, or vital energy, is then increased through abstinence or coitus reservatus. In Taoist sexuality or sexology manuals, this process is regularly described as follows: jing (the seed, raw and dense) is transformed into chi (vital energy, subtle and circulating).
Terminology
The present Chinese term comprises two disyllabic words.
() compounds two semantically complex words. () has English translation equivalents of: (1) "turn round, come round; go back, come back, return to previous location or to original condition; (re)cycle, revert", (2) "send back, send in return; answer. give back, remit; redeem; recompense; restore. rebound against one, come round again (whence it began)." (Kroll 2015: 170; note, all definitions condensed to relevant meanings). () translates as: (1) "essence; purest, most highly concentrated element (< finest bleached rice). pith, marrow, gist", (2) "germinal essence, life-germ contained in the Dao. the energy that nourishes the human body and is esp. attached to sexuality (semen, menstrual fluid); seminal; vital; seed(ling)", (3) "quintessence; purest, finest, most characteristic, very best of. concentrate(d), condensed, consolidated. subtle; delicate, fine." (Kroll 2015: 216). Although means "semen" in the expression , "it would be a great mistake to read as always referring only to the material secretion itself" (Needham and Lu 1983: 66). The "making the semen return upwards to nourish the brain" technique was another instance of the Daoist emphasis on "reversion, restoration, regeneration, counter-current motion. and cyclical transformation" (Needham and Lu 1983: 31).
() compounds two comparatively simpler words. () has equivalents of: (1) "mend or patch clothing", (2) "repair, restore; remedy, redress; improve, ameliorate", (3) "add to, supplement; supplete, supply (a deficiency); replenish." (Kroll 2015: 29). () translates into English as: "the brain. [medieval Chinese] one's head, noggin: also, top part." (Kroll 2015: 320).
There is no standard English translation of Chinese huanjing bunao, and here are twenty samples:
"making the return to restore the brain" (Needham and Wang 1956: 150)
"making the semen return to strengthen the brain" (van Gulik 1961: 78)
"reverting the sperm to repair the brain" (Ware 1966: 140)
"making the essence return (so as) to repair the brain" (Maspero 1981: 495)
"making the semen return upwards to nourish the brain" (Needham and Lu 1983: 30)
"returning the seminal essence and replenishing the brain" (Harper 1987: 549)
"making the seminal essence return to nourish the brain" (Ruan 1991: 96)
"returning the to nourish the brain" (Wile 1992: 50)
"to return of the essence to repair the brain" (Schipper 1993: 242)
"return [semen's] essence to the brain to fortify it" (Bokenkamp 1997: 87)
"returning the essence to replenish the brain" (Harper 1998: 151)
"conducting the seminal essence to repair the brain" (Baldrian-Hussein 2004: 808)
"return of the sperm in order to repair the brain" (Schipper 2004: 786)
"returning the essence to replenish the brain" (Despeux 2008: 515)
"returning the semen to supplement the brain" (Judy 2015: 135)
"returning the sperm to nourish the brain" (Umekawa and Dear 2018: 216)
"reverting the essence to replenish the brain" (Pregadio 2022: 438)
"to revert the essence and to replenish the brain (marrow)" (Pfister 2022: 344)
"return the essence to nourish the brain" (Wang 2022: 359)
"returning the semen to the brain" (Rocha 2022: 384)
Huan (還) is usually translated as "return", except for three "revert" and one "conduct". Jing (精) is rendered as seven "essence", four "semen", three "seminal essence" and one "[semen's] essence", three "sperm", and two "ching"—in Chinese usage, both jingzi (精子) and jingye (精液) mean "semen; sperm". Bu (補) is given as five each for "repair", "replenish", and "nourish"; and one each for "strengthen", "fortify", "supplement", "restore", and untranslated (Rocha 2022). Nao (腦) consistently has nineteen "brain" translations and one "brain (marrow)". Overall, there is notable diversity among these translations of the phrase, only two (Harper 1998 and Despeux 2008) are identical "returning the essence to replenish the brain"; and some translators revised their earlier versions, such as (Harper 1987, 1998) and (Needham 1956, 1983).
Scholars have discussed the Chinese sexual practice and related Western techniques in Latin biological terms based on coitus (meaning "sexual intercourse").
(from interruptus "interrupted, cut short"), commonly known as the "withdrawal method" or "pulling out," is an ancient contraceptive method consisting in removing the penis from the vagina before ejaculation.
(saxonicus "Saxon, West Germanic tribes") or (thesauratus "repository, treasure") is a widespread birth-control method consisting of squeezing the urethra at the base of the penis before ejaculation, resulting in retrograde ejaculation.
(with reservatus "reserved, saved") or (conservatus "preserved, conserved") Is a practice aimed at delaying or preventing orgasm or ejaculation. This can be achieved by stopping intercourse before reaching orgasm. Alternatively, it can be done by contracting the perineum or applying pressure to it with the fingers (the latter method not being recommended for health reasons), which can cause a retrograde ejaculation.
The sinologist Joseph Needham refined his translations of . Initially, he held that the technique was not as van Gulik "inadvertently" said, but ", numerous intromissions with a succession of partners occurring for every one ejaculation." (Needham and Ling 1956: 149). Subsequently, Needham reconsidered the problems of nomenclature. should neither be translated because that term is reserved for "the contraceptive method of sudden withdrawal and external ejaculation," nor because that usually means "allowing the state of excitation to fade without a withdrawal". He suggested two neologisms for accurately translating the Chinese methods; for "seminal retention and withdrawal after female orgasm" and for the retrograde ejaculation "'re-routing' of the secretion into the bladder". (Needham and Lu 1983: 199). Authors inconsistently use these terms for both coitus siccus "copulation without ejaculation" and coitus pluvius "copulation followed by ejaculation".
Note that in quotations below, the romanization of Chinese is standardized into Pinyin, for instance, Wade-Giles , Simplified Wade (used by Needham), and other transcription systems are converted to (, "breath; vital force").
Han dynasty
The archeological discovery and analysis of medical manuscripts in the 1970s revealed that the origins of Chinese sexual cultivation techniques dated back to at least the Warring States period (c. 475–221 BCE), rather than the early Han dynasty (202 BCE-220 CE), as previously believed (Needham and Lu 1983: 199).
Mawangdui excavated texts
Seven previously unknown medical and sexological manuscripts, along with the famous Mawangdui Silk Texts, were excavated in 1973 from a Western Han tomb dated 168 BCE (see Harper 1998 for details). Five were written on silk, such as the (Recipes for Fifty-Two Ailments), and the other two manuscripts written on bamboo and wooden slips each transcribed two different texts bound separately and rolled together in a single bundle. Although none of them directly refer to the , "returning the semen/essence to replenish the brain") techniques, three sexual cultivation bamboo-slip manuscripts mention aspects later associated with essence retention, accumulating and enclosing within the body, stimulating the penis, contracting the anus, and controlled stages of intercourse with ejaculation, all of which were believed to increase longevity and spiritual enlightenment. In the Mawangdui medical manuscripts, Chinese "essence" consistently names an internal material similar in nature to "vapor", and is not equivalent to "semen". In fact, no word for "semen" occurs although it is implicit in several passages (Harper 1998: 152).
First, the (, Ten Questions) manuscript consists of ten dialogues between legendary sages including the Yellow Emperor, Yao, and Shun. One passage exemplifies Chinese euphemisms referring to sexual terminology.
When coitus with Yin [, "sexual intercourse"] is expected to be frequent, follow it with flying creatures. The spring dickeybird’s [ (, "sparrows; other small wild birds")] round egg arouses that crowing cock [ (, "crowing cock") can refer to both the male bird and the man's penis]. The crowing cock has an essence. If you are truly able to ingest this, the jade whip [penis] is reborn. Best is engaging the member. Block that jade hole [vagina]. When brimming then have intercourse, and bid farewell with round eggs. If the member is not engaged, conserve it with roasted-wheat meal. If truly able to ingest this, you can raise the dead [revitalize the penis]. (Harper 1998: 443, 456-458)
Both the and the below describe accumulating and enclosing ("semen; life essence") in an enigmatic corporal space called the (, "jade closure"), where (, "spiritual illumination") occurs. Harper notes () is a standard term for "concentrating vapor and essence inside the body by 'enclosing' them" (1998: 457). (, "hold the breath closed in; apnea") is a related word used in embryonic breathing (Maspero 1981: 342).
[manuscript lacuna …] and take the essence. Attend to that conjoining of vapor [ , "sexual intercourse"], and lightly move her form. When able to move her form and bring forth the five tones [a woman's vocalizations during sex], then absorb her essence. Those who are empty can be made brimming full; the vigorous can be made to flourish lastingly; the aged can be made to live long. The procedure for living long is to carefully employ the jade closure. When at the right times the jade closure enfolds, spirit illumination arrives and accumulates. Accumulating, it invariably manifests radiance. When the jade closure firms the essence, this invariably ensures that the jade wellspring [ ] is not upset. Then the hundred ailments do not occur; thus you can live long. (Harper 1998: 444, 458)
The subsequent passage lists nine stages of (, "arrival; 'coming'", i.e., "thrusting the penis inside the vagina") without ejaculation.
In the way of coitus with Yin [intercourse], stay the heart, settle and secure it; and the form and vapor secure one another. Thus it is said: at the first arrival without emission, ears and eyes are perceptive and bright; at the second arrival without emission, the voice’s vapor rises high; at the third arrival without emission, skin and hide glow; at the fourth arrival without emission, spine and upper side suffer no injury; at the fifth arrival without emission, buttock and ham can be squared; at the sixth arrival without emission, the hundred vessels pass clear through; at the seventh arrival without emission, your entire life is without calamity; at the eighth arrival without emission, you can have a lengthy longevity; at the ninth arrival without emission, you penetrate spirit illumination. (Harper 1998: 444, 458)
Some Mawangdui manuscript paleographers suggest that the contains the earliest documentation of ("returning the essence to replenish the brain"), depending upon whether the unusual character () should be read as a copyist's error for (, "brain") or a graphic loan character for (, "womb; placenta"). The context describes an ancient method for "coitus with Yin to become strong" and "sucking in heaven's essence to achieve longevity." King Pan Geng is told,
Your lordship must prize that which is born together with the body and yet grows old ahead of the body [the penis]. The weak, it makes them strong; the short, it makes them tall; the poor, it guarantees them abundant provisions. The regimen involves both emptying and filling, and there is a precise procedure for cultivating it. First, relax the limbs, straighten the spine, and flex the buttocks; second, spread the thighs, move the Yin [penis], and contract the anus; third, draw the eyelashes together, do not listen, and suck in the vapor to fill the womb []; fourth, contain the five tastes and drink that wellspring blossom an internally produced fluid; fifth, the mass of essence all ascends, suck in the great illumination. After reaching the fifth, stop. Essence and spirit grow daily more blissful.” (Harper 1998: 449, 465-467)
Wile translates as "brain", "stimulate the penis ... contract the anus ... absorb the [] to fill the brain ... all the [] will rise upward" (1992: 58). However, based upon similar textual usages, Harper translates it as "womb", hypothetically meaning "a 'womb-like organ' where men as well as women store vapor and essence", and disputes the "brain" interpretation because "filling the womb" occurs in the third of five stages, whereas "replenishing the brain" is regularly the final stage in sexual cultivation (1998: 465–467).
Second, the (, Conjoining/Uniting Yin and Yang; a standard term for sexual intercourse) manuscript begins with a jargonized method for doing it,
Grip the hands [make a fist with the thumb tucked in], and emerge at the Yang side [outside] of the wrists; Stroke the elbow chambers; Press [or go to] the side of the underarms; Ascend the stove trivet [between the breasts]; Press the neck zone; Stroke the receiving canister [pelvic region]; Cover the encircling ring [waist]; Descend the broken basin [clavicle]; Cross the sweet-liquor ford [breasts]; Skim the Spurting Sea [navel]; Ascend Constancy Mountain [female genitals]; Enter the dark gate [vagina]; Ride the coital muscle [responsible for the female orgasm]; Suck the essence and spirit upward. Then you can have lasting vision and exist in unison with heaven and earth. (Harper 1998: 473, 477, 479).
Compare the parallel above saying the "mass of essence all ascends". In contrast with this "essence and spirit" translation for (), Wile translates "By sucking her spirit upward" and notes " spirit" should be understood as "essentially sexual energy." (1992: 78, 223). This context continues with the "signs of the five desires" (e.g., the second is "the nipples harden and her nose sweats—slowly embrace") and says,
When the signs are complete, ascend. Jab upward but do not penetrate inside, thereby bringing the vapor []. When the vapor arrives penetrate deeply inside and thrust it upward, thereby dispensing the heat. Then once again bring it back down. Do not let the vapor spill out, lest the woman become greatly parched. (Harper 1998: 474)
In the last sentence, Harper reads the manuscriptal (, "peg; tally") as a graphic loan character for (, "forceful; parch") meaning that when intercourse is excessive, "the penis must still block the vaginal opening in order to seal the sexually generated essence inside" (1998: 481, 501).
A subsequent passage differentiates essences by gender.
In the evening the man’s essence flourishes; in the morning the woman’s essence accumulates. By nurturing the woman’s essence with my essence, muscles and vessels both move; skin, vapor, and blood are all activated. Thus, you are able to open blockage and penetrate obstruction. The central cavity receives the transmission and is filled. (Harper 1998: 476, 484).
Third, the (, Discussion of the Culminant Way in Under-Heaven) bamboo document says that enclosing ("essence") can result in achieving (, "spirit illumination").
O be careful indeed! The matter of spirit illumination lies in what is enclosed [ ]. Vigilantly control the jade closure [ ], and spirit illumination will arrive. As a rule, to cultivate the body the task lies in accumulating essence. When essence reaches fullness, it invariably is lost; when essence is deficient, it must be replenished. As for the time to replenish a loss, do it when essence is deficient. To do it, conjoin in a sitting position; tailbone, buttocks, nose, and mouth each participate at the proper time [i.e., engage in sexual intercourse]. (Harper 1998: 491, 498)
Compare Wile's above translation of (, "jade closure"), "The matter of achieving spiritual illumination consists of locking. If one carefully holds the "jade" in check, spiritual illumination will he achieved." (1992: 80).
Another context, described as the "free-handed method" (Pfister 2022: 343), refers to anal constriction during sexual coitus, but does not specify pressing on the (, "usurp; perineum")
While having intercourse, to relax the spine, suck in the anus, and press it down is “gathering vapor.” While having intercourse, to not hurry and not be hasty, and to exit and enter with harmonious control is “harmonizing the fluid.” When getting out of bed, to have the other person make it [the penis] erect and let it subside when angered is “accumulating vapor.” When nearly finished, to not let the inner spine move, to suck in the vapor press it down, and to still the body while waiting for it is “awaiting fullness.” To wash it after finishing and let go of it after becoming angered is “securing against upset.” (Harper 1998: 493, 500)
Washing the penis is intended to bring about detumescence (Harper 1998: 501).
Received texts
Prior to the Mawangdui discoveries, scholars relied on received texts of Chinese classics to understand the origins of . For instance, the bibliographical section of the 111 CE Book of Han lists the (, Rong Cheng's Way of Lovemaking) in 26 chapters, along with several other lost texts on sexual cultivation.
The earliest known attestation of is the c. 2nd century CE commentary (to 9) that condemns the practice (Harper 1998: 467). At this early stage of practice, note the use of (, "think, think of") denoting "contemplate, meditate" on essence rather than semen.
The Dao teaches people to congeal their essences and form spirits []. Today, there are in the world false practitioners who craftily proclaim the Dao, teaching by means of texts attributed to the Yellow Thearch, the Dark Maiden, Gongzi, and Rongcheng. They say that during intercourse with a woman one should not release the semen, but through meditation return its essence to the brain to fortify it []. Since their [internal] spirits and their hearts are not unified, they lose that which they seek to preserve. Though they control their delight, they may not treasure it for long. (Bokenkamp 1997: 43)
Based upon a misquotation in the transmitted 5th century Book of the Later Han, several authorities have contended that was first recorded in the 2nd century CE ("Biographies of Exemplary Transcendents") hagiography of Rong Chenggong (), one of the semi-legendary founding fathers of Chinese sexology: "One should firmly hold [the penis] with the hand, not ejaculate, and let the essence revert to replenish the brain." (Despeux 2008: 515).
The Book of the Later Han biography of Ling Shouguang () says he was an expert on the sexual techniques of Rong Cheng, and the commentary quotes the .
The Venerable Rong Cheng was good at the affairs of 'restoring' [ ] and 'conducting' [ ]. He could gather the [] from the 'Mysterious Feminine'. The essential point of this art is to guard the life-force and to nourish the [] by (relying on) the 'Valley Spirit that never dies' [both the Mysterious Feminine and Valley Spirit refer to the 6]. When this is done white hairs become black again, and teeth that have dropped out are replaced by new ones. The art of commerce [intercourse] with women is to close the hands tightly and to refrain from ejaculation, causing the sperm to return and nourish the brain. (Needham and Lu 1983: 198).
Although Needham and Lu claim the last sentence was "expurgated" from the original , the reference belongs to the commentary and not the original text (Harper 1998: 467).
The Quanzhen School hagiographer Zhao Daoyi (, fl. 1294–1307), compiler of the (, Comprehensive Mirror of Immortals Who Embodied the Way Through the Ages), notes he chose to omit the tradition that "Some say that Sire Rong Cheng obtained the art of 'riding the woman,' by which one firmly grasps [the seminal vesicle] in order not to leak out the semen [but rather] cause it to return and so nourish the brain" because it probably resulted as "an erroneous divergence [from the earlier legend] by later generations." (Campany 2002: 534–535)
The reconstructed 2nd or 3rd century (, The Classic of the Pure/Plain Woman) defines (, "returning the essence") as "to be aroused but not ejaculate", describes a man gathering and transforming the from a woman's mouth and returning it into his brain, and details the pleasures of refraining from ejaculation.
First, the Yellow Emperor asks Sunu about the results of refraining from intercourse for a long time, and she answers.
If the "jade stalk" [penis] does not stir, it dies in its lair. So you must engage frequently in intercourse as a way of exercising the body [ ]. To be aroused but not ejaculate is what is called "returning the []." When the is returned to benefit the body [], then the tao of life has been realized. (Wile 1992: 85)
Needham mistranslates (, "exercise; calisthenics; breath circulation") as "masturbation", despite correctly translating it more than ten times elsewhere in the book as "gymnastic techniques" and "massage" (Wile 1992: 59).
Therefore (if you insist on refraining from women) you should regularly exercise it (the Jade Stalk) by masturbation. If you can erect it (in orgasm) and yet have no ejaculation, that is called 'making the return', and making the return is of great restorative benefit, fully displaying the Tao of the life(-force). (Needham and Lu 1983: 201).
Second, the legendary ruler asks Sunu about how to regain strength when he cannot get an erection, and she recommends first harmonizing with his partner, then gathering her , transforming it into (), and returning it to the brain.
The woman manifests "five colors" [displaying her mood] by which to assess her satisfaction. Gather her overflowing [] and take the liquid from her mouth. The will be returned and transformed in your own body [], filling the brain []. (Wile 1992: 86)
The translator notes that (, "return") denotes the "process of raising the energy from its center at the base of the body up the back to the brain", and reads the character (, "dirty; defile") following as a variant of (, "brain"), that is, "return the to fortify the brain" (1992: 234).
Third, the goddess Cainü (, Selected Woman) asks Peng Zu, "The pleasure of intercourse lies in ejaculation. Now if a man locks himself and refrains from emission, where is the pleasure?", and he answers:
When is emitted the whole body feels weary. One suffers buzzing in the ears and drowsiness in the eyes; the throat is parched and the joints heavy. Although there is brief pleasure, in the end there is discomfort. If, however, one engages in sex without emission, then the strength of our will be more than sufficient and our bodies at ease. One's hearing will he acute and vision clear. Although exercising self-control and calming the passion, love actually increases, and one remains unsatiated. How can this be considered unpleasurable? (Wile 1992: 91)
Six dynasties
The historical term "Six Dynasties" (222-589) collectively refers to the Three Kingdoms (220–280 CE), Jin Dynasty (265–420), and Southern and Northern Dynasties (420–589).
Ge Hong's c. 318 (Master Who Embraces Simplicity) provides early information about "returning the essence to replenish the brain" and related terms. occurs in two chapters. "The Ultimate System" lists it among common practices to nourish life.
Man's death ensues from losses, old age, illnesses, poisons, miasmas, and chills. Today, men do calisthenics and breathing exercises, revert their sperm to repair the brain, follow dietary rules, regulate their activity and rest, take medicines, give thought to their inner gods to maintain their own integrity, undergo prohibitions, wear amulets and seals from their belts, and keep at a distance all who might harm their lives. (5, Ware 1966: 103)
The "Resolving Hesitations" chapter praises the secret practice, which had always been orally transmitted.On the technology of sex at least ten authors have written, some explaining how it can replenish and restore injuries and losses, others telling how to cure many diseases by its aid, others again describing the gathering of the Yin force to benefit the Yang, others showing how it can increase one's years and protract one's longevity. But the great essential here is making the semen return to nourish the brain [], a method which the adepts have handed down from mouth to mouth, never committing it to writing. If a man does not understand this art he may take the most famous (macrobiotic) medicines, but he will never attain longevity or immortality. Besides, the union of Yin and Yang in sexual life should not be wholly given up, for if a man does not have intercourse he will contract the diseases of obstruction and blockage by his slothful sitting, and end by those which arise from celibate depression and pent-up resentment—what good will that do for his longevity? On the other hand, over-indulgence diminishes the lifespan, and it is only by managing copulations so that the seminal dispersals are moderated, that damage can be avoided. Without the (right) oral instructions hardly a man in ten thousand will fail to injure and destroy himself in practising this art. The disciples of the Mysterious Girl and the Immaculate Girl, with the Venerable [Rong Cheng], and [Peng Zu], all had a rough acquaintance with it, but in the end they never committed to paper the most important part of it. Those bent upon immortality, however, assiduously seek this out. As for myself, I had instruction from my teacher [Zheng Yin ], and I record it here for the benefit of future believers in the Tao, not retailing my own ideas. At the same time I must truthfully say that I feel I have not yet mastered everything that could be got from his instruction. (Lastly), some Taoists with a smattering of knowledge teach and follow the sexual techniques in order to pattern themselves on the holy immortals, without doing anything about the preparation of the great medicine of the Golden Elixir. Oh what a height of folly is this! (8, Needham and Lu 1983: 200-201)
The mentions with Taixi (embryonic breathing) (, "return the essence and breathe like an embryo") in the Rejoinder to Popular Conceptions chapter, which quotes a poem from a (, Scripture on Transcendence):
Those who take [chemical] elixirs / And guard the primal unity / Will come to a stop from living / No sooner than Heaven itself; / Making the sperm return, / Breathing like babe in womb, / They will lengthen their days in peace / And blessing, world without end. (3, Needham and Lu 1983: 200)
Compare "Revert your sperm, breathe like fetus" (Ware 1966: 54).
The Genie's Pharmacopoeia chapter lists brain-supplementing sophora seeds among Daoist transcendence drugs. "Seal with clay in a new jar for twenty days or more, until the skin has fallen off Then wash the seeds, and they will be like soybeans. Taken daily, they will be especially good for repairing the brain. If one takes them for a long time, one's hair will not turn white, and one will enjoy Fullness of Life." (Ware 1966: 190–191).
Besides the usual word ("sperm"), the synonymously uses (, "Yin elixir; sperm") in two contexts of (, "brain mending").
It is inadmissible that man should sit and bring illness and anxieties upon himself by not engaging in sexual intercourse. But then again, if he wishes to indulge his lusts and cannot moderate his dispersals, he hacks away at his very life. Those knowing how to operate the sexual recipes can check ejaculation, thereby repairing the brain []; revert their sperm to the Vermilion Intestine []. (6, Ware 1966: 122)
If a man in the vigor of youth learns how to revert his years [], repairs his brain with his sperm [], and gathers mucus from his nose, he will live not less than three hundred years without taking any medicines, but this will not bring him geniehood [transcendence]. (13, Ware 1966: 223).
The 2nd or 3rd century (, Jade Manual of the External Radiance of the Yellow Courts; compare the Shangqing revelations Inner Scripture) is "filled with cryptic expressions and divine names" designed to exclude uninformed readers, and is addressed to learned Daoists already familiar with techniques (Maspero 1981: 488, 523). For illustration,
The Mysterious Chest [inside of the throat] of the Breath Tube [tracheal artery] is the receptacle which receives the Essence; Take care to hold onto your Essence firmly and restrain yourself. […] Please yourself by exhaling and inhaling in the Hut [nose]; if you protect and keep (Essence and Breath) complete and firm, your body will receive prosperity; the interior of the Square Inch [Cinnabar Field], close it carefully and store up (its contents): when the Essence and the Spirit come back and turn around, the old man comes back to the prime of life; squeezing the Dark Door [kidneys] they all flow out below; nourish your Jade Tree [the body] so that it will be strong. (tr. Maspero 1981: 524-526)
The circulation of the Breath is completed by that of the Essence. While the basic meaning of is "sperm in men; menstrual blood in women"; this text uses it to mean "some sort of sublimation dematerialized and capable of blending with the Breath".
"In the middle of the Cinnabar Field, the Essence and the Breath are very subtle." It is in fact necessary to "make the Essence come back", []—that is, to make the Essence mingled with the Breath circulate through the body to guide it from the Lower Cinnabar Field to the Upper Cinnabar Field so that it "restores the brain", []. To be capable of this the Adept must first develop his Essence. The Immortal [Peng Zu] explains in fairly coarse terms how to go about this so as to arouse and agitate the Essence under the influence of the Breath, but without expending it, which would be a cause of weakening and would diminish the term of life, for "at all times when the Essence is small, one is sick, and when it is exhausted, one dies." Essence accumulates in the Lower Cinnabar Field; when it is strong enough, it blends with Breath. (Maspero 1981: 345).
There is a parallel between ("essence returning") and (, "breath holding"). In Daoist physiology, the spinal cord, was likened to the Yellow River in its "downward-radiating trophic influence", the allusively described with the phrase () "making the Yellow River flow backwards") (Needham and Ling 1956: 150).
The c. 4th century (, Essentials of the Jade Chamber) quotes the Han Daoist transcendent Liu Jing () about sexual intercourse.
The of mounting women is first to engage in slow foreplay so as to harmonize your spirits and arouse her desire, to and only after a long time to unite. Penetrate when soft and quickly withdraw when hard, making the intervals between advancing and withdrawing relaxed and slow. Furthermore. do not throw yourself into it as from a great height, for this overturns the Five Viscera and injures the collateral meridians, leading to a hundred ailments. But if one can have intercourse without ejaculating and engage several tens of times in one day and night without losing , all illnesses will be greatly improved and one's lifespan will daily increase. Even greater benefits are reaped by frequently changing female partners. To change partners more than ten times in one night is especially good. (Wile 1992: 101)
Maspero says this "elementary exercise" is sufficient for an adept who only wants to prolong life, but "making the Essence return to restore the brain" is necessary if one wants to achieve spiritual transcendence (1981: 522).
The ensuing passage quotes an anonymous (, Scripture on Transcendence/Immortality") that gives details of how to practice , where the diverted "jing" seems to be ordinary semen and not supernatrural "jingqi" (, "sexual energy; vitality") (Wile 1992: 48).
The classics on immortality say that the of "returning the to nourish the brain" is to wait during intercourse until the is greatly aroused and on the point of emission. and then, using the two middle fingers of the left hand, press just between the scrotum and anus. Press down with considerable force and expel a long breath while gnashing the teeth several tens of times, but without holding the breath. Then allow yourself to ejaculate. The , however, will not be able to issue forth and instead will travel from the "jade stalk" [ , "penis"] upward and enter the brain. This method has been transmitted among the immortals who are sworn to secrecy by blood pact. They dared not communicate it carelessly for fear of bringing misfortune on themselves. (Wile 1992: 101)
Citing this early description of the urethral pressure method, Pfister says a few people consider it "a beginner’s practice, which should, after some training, be replaced by the free-handed procedure" (2022: 344).
Needham and Lu reason that "making the semen return to nourish the brain" originated at some very early time during the Zhou dynasty (1046 BCE – 256 BCE), when the discovery was made that if pressure was applied at "the right point in the perineal region the urethra could be occluded, so that at the moment of orgasm the semen instead of being ejaculated could be made to pass into the body." The fact that it passed into the bladder and was later urinated always escaped the notice of the Daoists, and "over more than two thousand years a great structure of theory grew up" concerning how the precious secretion of essence was conveyed up into the head and ultimately to the center of the body for the preparation of the internal elixir (1983: 197–198).
Next, the describes how to (, "stop; suppress; still") ejaculating , without mention of "returning" it to the brain or "absorbing" it from the partner.
If one desires to derive benefit from mounting women, but finds that the is overly aroused, then quickly lift the head, open the eyes wide and gaze to the left and right, up and down. Contract the lower parts, hold the breath and the will naturally be stilled. Do not carelessly transmit this to others. Those who succeed in shedding their but twice a month, or twenty-four times in one year, will all gain long life, and at 100 or 200 years will be full of color and without illness. (Wile 1992: 101)
The pre-Sui c. 4th century (, Secrets of the Jade Chamber) expands the semantic range of the ("return the sperm/essence to nourish the brain") vocabulary. This text uses "jing" and "qi" more or less interchangeably, the "woman's sexual energy" in one instance being called () and in another similar context (). Elsewhere, () refers to both" male and female sexual essences" (Wile 1992: 48). In the following examples of passages, instead of "returning the " to the brain, the text mentions "return the and restore the fluid [ ]", "mounting the 'vast spring and returning the ", and "return the [, "essence and breath"]". Another comparable illustration of semantic polysemy is the word (, lit. "seminal/essential fluid"), which Wile translates as "semen", " secretions", and "fluids".
First, "return the " is paired with (, "restore the fluid") and is translated as "semen".
The of and ; is to treasure the semen []. If one can cherish it, one's life may be preserved. Whenever you ejaculate you must absorb the woman's to supplement your own. The process of "reestablishment by nine" means practicing the inner breath nine times []. "Pressing the one" refers to applying pressure with the left hand beneath the private parts [] to return the and restore the fluid []. "Absorbing the woman's is accomplished by "nine shallow and one deep" strokes. Position your mouth opposite the enemy's mouth and exhale through the mouth. Now inhale, subtly drawing in the two primary vitalities, swallow them and direct the with the mind down to the abdomen, thereby giving strength to the penis []. (Wile 1992: 104)
Second, "returning the " occurs after absorbing the woman's (, " secretions") and mounting the (, the "vast spring"), which may mean "female genitalia" (Wile 1992: 251).
Those who seek to practice the of uniting yin and yang for the purpose of gaining and cultivating life must not limit themselves to just one woman. You should get three or nine or eleven; the more the better. Absorb her secretions [] by mounting the "vast spring" and "returning the []" Your skin will become glossy, your body light. your eyes bright, and your so strong that you will be able to overcome all your enemies. Old men will feel like twenty and young men will feel their strength increased a hundredfold. (Wile 1992: 102)
Third, the expands the standard "return the " to with (, "; breath"). This context claims the health benefits of avoiding ejaculation include achieving clear vision, preventing deafness, and regulating the Five Viscera.
The for achieving clear vision is to wait for the impulse to ejaculate and then raise the head, hold the breath, and expel the air with a loud sound, gazing to the left and right. Contract the abdomen and return the so that it enters the hundred vessels []. (Wile 1992: 104)
(, "pulse; artery; vein") in this (, "hundred vessels") occurs in another passage where is simply translated as "fluids".
If a woman knows the way of cultivating her and causing the two to unite harmoniously, then it may be transformed into a male child. If she is not having intercourse for the sake of offspring, she can divert the fluids to flow back into the hundred vessels []. By using to nourish , the hundred ailments disappear, one's color becomes radiant and the flesh fine. One can enjoy long life and be forever like a youth. (Wile 1992: 103)
The pre-Tang c. 5th century Dong Xuanzi (, Master of the Cavern of Mystery), named after the (, "Mystery Grotto"), which is one of the Three Grottoes in the Daoist canon. One passage lists a number of standard techniques for ejaculation control, mentioning neither squeezing the penis base nor pressing the perineum, and concludes, "the jing will rise of itself."
Whenever one desires to ejaculate, one must await the woman's orgasm and then bestow the , ejaculating at the same time. The man should withdraw to a shallow depth and play between the "zither strings" [] and "wheat teeth []." The " sword tip" [] moves deep and shallow like an infant sucking the breast. Then one closes the eyes and turns one's thoughts inward. As the tongue is pressed against the lower palate, arch the back, stretch out the head, dilate the nostrils, hunch the shoulders, close the mouth and inhale, and the will rise of itself []. The degree of control is always dependent on the individual. One should only ejaculate two or three times in ten. (Wile 1992: 111-112)
Chinese sex manuals variously list terms for vaginal depths, beginning with the shallowest (, "zither strings; Labia minora") and (, "wheat teeth"), between which is the optimum depth for ejaculation (Wile 1992: 236, 243, 255).
The c. 5th century (, Biography of Lord Pei, the Realized Person of Pure Refinement)
(The couple) should be free from the effects of wine or repletion of food, and they should be clean of body, for otherwise illness and disease will afflict them. First by means of meditation they must have put away all worldly thoughts, then only may men and women practise the Tao of life eternal. This procedure is absolutely secret, and may be transmitted only to sages; for in it men and women together lay hold of the of life, cherishing and nourishing respectively the seminal essence and the blood. It is not a heterodox thing. In it the is gathered up in order to benefit the . If one practises it according to the rules, the and the fluids will circulate like clouds, the pure wine of the will coagulate harmoniously, and whether one is old or young one will revert to the state of youth. [… After completing some prayers, the man and woman begin coition] The man guards (controls) his reins (i.e., his libido), keeping firm grasp of his semen and refining its , (till eventually) they ascend along the spinal column to the brain going against the (normal) current. This is called 'regenerating the primary (vitalities; )'. The woman guards (controls) her heart (i.e., her emotions) and 'nourishes her ,' not allowing the refined fire to move (, , i.e., refraining from orgasm), but making the of her two breasts descend into her reins, and then also rise up from there (along the spinal column) to reach the brain. This is called 'transforming (life) into the primary (vitalities; )'. (Needham and Lu 1983: 205-206).
Sui to Tang dynasties
In Sui (561-618) and Tang (618-907) dynasty sex manuals, the "return," "circulation," or "rising" of the takes place "naturally as a result of simultaneous stimulation and ; and that male and female sexual energy usually are treated in separate passages in the texts and never explicitly linked" (Wile 1992: 48).
The Tang (, Health Benefits of the Bedchamber) was preserved in Sun Simiao's 652 classic medical reference (Essential Prescriptions Worth a Thousand) (chapter 83). This text includes the ejaculation control techniques found in earlier sources, but also adds several new elements. First, it introduces the discovery that "frequent sex with occasional ejaculation is less depleting than occasional sex with habitual ejaculation", which supports the theory that frequent intensifies sexual power. Second, it presents meditative visualizations and yogic postures for precoital preparation and postcoital absorption, for instance, "Imagine a red color within the navel the size of a hen's egg" for deep penetration without arousing the . Third, the text emphasizes the importance of absorbing from "above", meaning the woman's breath (Wile 1992: 48).
When one feels the impulse to ejaculate, close the mouth and open the eyes wide, hold the breath and clench the fists. Move the hands to the left and right, up and down. Contract the nose and take in . Also constrict the anus, suck in the abdomen, and lie on the back. Now quickly press the point with the two middle fingers of the left hand. Exhale a long breath and at the same time gnash the teeth a thousand times. In this way the will ascend to nourish the brain [], causing one to gain longevity. (Wile 1992: 116)
(, "screen shade") is an alternate name for the Conception vessel CV-1 (, Yin Meeting) acupoint at the perineum (Wile1992: 263).
The c. 785 (, Confidential Oral Instructions of the Adept of Mount Wangwu, Presented to the Court by Liu Shou), which is contained in the c. 1029 Daoist Canon, refers to in several passages.
The Yang enchymoma [ , Needham's neologism for "elixir within; inner elixir"] can make one ascend (into the heavens); the Yin enchymoma can confer longevity. The Yang enchymoma is a 'returning' (i.e., regenerative) medicine, the Yin enchymoma is the (regenerative) technique of making the return []. (Needham and Lu 1983: 204)
There is an analogy between party etiquette and having sex.
One should not dare to be the host, but rather play the part of the guest. We can borrow from the Taoist manuals in speaking of these affairs. He who first lifts up the cup (at a party) is the host, he who responds is the guest. The host first pours out benefits for others, but the guests are those who receive. If one gives like this one's is dispersed and one's emotions are exhausted. But if one receives, one's is strengthened and one's emotions concentrated. This is because the absorption of the of union assists one's own (primary) Yang—in that case what is there to worry about?
The text then goes on to explain the (, "riding the wine-pot") technique of "applying the perineal pressure in with the heel rather than the hand", and quotes an old Daoist saying that: "Who wishes life unending to attain, Must raise the essence to restore the brain []."
The being elevated against the current, both the man and the woman can become immortals and obtain the Tao. … Thus all the old Taoist traditions say that if (the semen is) ejaculated it leads to other men, that is to say, a child is born, but if it is retained it leads to the man himself, that is to say, an (immortal) body is born—that is the meaning of it. (Needham and Lu 1983: 208-209; cf. 159)
Concurrent with historical developments of Daoism, the technique of "Returning the essence to replenish the brain" evolved from sexual yoga to cosmic meditation. This method originally consisted of controlling the flow of (, "seminal essence"), and was related to (lit. "bedchamber arts", "lovemaking techniques") and ("longevity practices") (Despeux 2008: 514). During the Tang dynasty, (Inner Alchemy) became popular and took on a different meaning that refers to the repeated cycling of the essence in the first stage of the practice, called (, "celestial circuit; continuously circular movement of the universe") (Despeux 2008: 515).
By the end of the Tang dynasty, many Chinese sex manuals were no longer extant, and only known by titles listed in bibliographies. Fortuitously, the Japanese physician Tamba Yasuyori (, 912–995) compiled and published many fragments of early Chinese medical writings in his 984 Japanese (, Formulas of the Heart of Medicine), which was partly based on the 7th century (General Treatise on the Etiology and Symptomology of Diseases). Chapter 28 of the , Japanese (, Art of the Bedchamber) contains several texts, such as the . The Chinese editor Ye Dehui republished them in his 1907 (, Shadow of the Double Plum Tree Anthology), which outraged many Chinese readers.
Song, Yuan, and Ming dynasties
Sex manuals continued to be published during the Song (960-1279), Yuan (1271–1368), and Ming dynasties (1368–1644).
The c. 1020 (, Dangers and Benefits of Intercourse with Women) is chapter 6 of the (, "On Nourishing Inner Nature and Extending Life"), attributed to Tao Hongjing or Sun Simiao.
It presents some new themes, such as postejaculatory remediation, advising to supplement leaked semen by engaging in exercise to "circulate energy internally", and an early description of cloudy urine from retrograde ejaculation (Pfister 2022: 345).
To lock the [] by repression is a practice difficult to maintain and easy to lose. Furthermore, it causes a man to lose through leakage and for his urine to be turbid. It may even lead to the illness of copulation with ghosts. Also, by seeking to prevent the from becoming excited, they weaken their principle. Those who desire to have intercourse with women should first become aroused and cause [the penis] to rise up strong. Slowly engage her and absorb her . Circulate the and after a moment you will become strong. When strong, employ it, being certain to move slowly and in a relaxed manner. When your becomes aroused, stop. Lock the and slow the breath. Close the eyes. lie on the back and circulate your internal energy. When the body returns to normal, one may have intercourse with another woman. (Wile 1992: 120)
Another passage describes some more serious consequences of losing "seminal essence".
Some are shocked into insanity or experience "emaciation-thirst" disease [ ]. Some lose their minds or suffer malignant sores. This is the result of loss. When emission does occur, one should circulate energy internally to supplement the loss in that area. Otherwise, the blood vessels and brain daily will suffer more harm. When wind and dampness attack them they take ill. This is because common people do not understand the necessity of supplementing what is lost in ejaculation. (Wile 1992: 120)
Unlike earlier texts recommending the sexist concept of male release and absorption from females, the is the first to describe a path of mutual immortality for both sexes through a combination of deep penetration, low arousal, and visualizations (Wile 1992: 48).
The classics on immortality state that the tao of man and woman achieving immortality together is to use deep penetration without allowing the to be aroused. Imagine something red in color and the size of an egg in the middle of the navel. Then slowly move in and out, withdrawing when the becomes aroused. By doing this several tens of times in the morning and in the evening, one may increase the lifespan. Man and woman should both calm their minds and maintain their concentration. (Wile 1992: 121)
Lastly, this text misquotes the : "If one returns the to nourish the brain, one will never grow old []." (Wile 1992: 126); suggesting that this () may literally mean "old one, or wise one" author rather than text (1992: 265).
The c. 1029 quotes the (, The Ranks of Spirits and Substances, a Dongzhen Scripture of the Supreme Clarity Heavens), which paraphrases :
The primary () is (the main factor of) life and death; life and death depend on the art of the bedchamber. One must follow the method of the Tao of retention, so that the can be changed into something wonderful; one must make this flow and circulate incessantly without hindrance or obstruction. As the proverb says: 'Running water doesn't rot, and a door often used is not eaten by woodworms.' Those who understand the mystery within the mystery know that a man and a woman can together restore (their vitality), and both can become immortals; this is truly what may be called a marvel of the Tao. The manuals of the immortals say: 'One Yin and one Yang constitute the Tao; the three primary (vitalities) and the union of the two components; that is the [inner elixir]'. When the flow goes up against the stream to nourish the brain, this is called 'making the return' () []. (Needham and Lu 1983: 124)
The early 13th-century (, Teacher Dou's South-Pointer for the Regeneration of the Primary [Vitalities], from the Western Sacred Mountain) lists the (, "seven precious things")— (), (), (, "vessels and nerves"), (), (, "blood"), (, "saliva"), and (, "juices of organs")—necessary for the (, "seven reversions"). It says, "if the juices are abundant they can generate saliva, if the saliva is abundant it can change into blood, if the blood is abundant it can be transmuted the (seminal essence), if the is abundant it can (be sent up to) nourish the brain, if the brain is nourished it can strengthen the , and if the is copious it can complete and perfect the ." (tr. Needham and Lu 1983: 151).
The Ming c. 1500 (, Wondrous Discourse of Sunü) presents a new theory with a parabolic curve of sexual vitality, peaking at middle age, which separates the concept of sexual energy from simple ejaculatory potency (Wile 1992: 48).
A boy reaches puberty at sixteen, but his vitality is not yet sufficient and his mind not yet stable. He therefore must observe abstinence. When he reaches the age of twenty, his vitality is becoming stronger, and the is concentrated in the intestines and stomach. One may then ejaculate once in thirty days. At thirty, the vitality is strong and abundant, and the is in the thighs. One may ejaculate once in five days. At forty, the is concentrated in the lower back and one may ejaculate once in seven days. At fifty, the vitality begins to decline, and the is concentrated in the spine. One may then ejaculate once in half a month. When one reaches sixty-four years of age, the period of one's potency is finished and the cycle of hexagrams complete. The vitality is weak and the secretions exhausted. If one can preserve one's remaining after sixty, then those who are vigorous may still ejaculate. When one reaches seventy, one must not let the emotions run wild. (Wile 1992: 131).
The explains self-cultivation through absorbing a partner's energy and supplementing oneself:
"Heaven and earth combine prosperously" and and cooperate generously. First examine her state of emotional excitement and then observe whether the stages of arousal have reached their peaks or not. Energetically withdrawing and inserting, one realizes the marvel of "adding charcoal." This secures and strengthens one's own " coffers." Enjoying scented kisses and pressing closely together, absorb her to supplement your []. Draw in the of her nostrils to fortify your spine marrow []. Swallow her saliva to nourish your [elixir-field in the lower abdomen]. Cause the hot to penetrate the [center of the brain] point and permeate the four limbs. As it overflows, it strengthens the and blood, preserves the complexion, and prevents aging. (Wile 1992: 133)
The 1615 Ming dynasty compendium of Inner Alchemy pictures an adept practicing . The "Illustration of Reverse Illumination" shows the vertebral column, which is flanked by the (, "TCM kidneys")—distinct from the anatomical kidneys—which are respectively labeled as (, "dragon fire") on the right, a symbol of yang energy within the yin side of the body, and (, "tiger water") on the left, a symbol of yin energy within the yang side of the body (Little 2000: 348–349). This illustration shows twenty-four "vertebra", some labeled with the traditional Chinese medical acupoint names for fourteen of the twenty-eight points of the () Governing Vessel. The relevant acupoints are GV-1 (, Long and Strong) halfway between the coccyx and the anus, and Conception vessel CV-1 (, Yin Meeting) halfway between the scrotum and the anus (Needham and Lu 1983: 231).
Cross-cultural counterparts
Although the Daoist practice of "returning the seminal essence to replenish the brain" may seem to be a uniquely Orientalist mystery, there are historical counterparts in the fields of Ancient Greek medicine and Tantric sex.
In Ancient Greece, some physicians and philosophers believed that semen originated in the brain and moved through the spinal marrow. Plato's c. 360 BCE Timaeus dialog considered the brain and spinal marrow as a special form of bone marrow in which "God implanted his divine seed" (Noble 2014: 399). The marrow supposedly passes down the spine and communicates its "universal seed stuff" to the genitalia for procreative purposes. "And the marrow inasmuch as it is animate and has been granted an outlet from the passage of egress for drink [the penis] has endowed that part with a love for generating by implanting therein a lively desire for emission" (Noble 2014: 400).
Regarding the semen, Hippocrates (c. 460- c. 370 BCE) said, "The greater quantity of the material of generation, it is believed on the authority of Galen, is drawn from the brain." (, ). This refers to the Pseudo-Galen , "The semen, as Plato and Diocles opine, is discharged by the brain and the spinal marrow, while Praxagoras and Democritus and thereafter Hippocrates maintain it comes from the whole body." (Noble 2014: 397)
Based upon contemporary medical resources, the anatomical drawing by Leonardo da Vinci (1452 – 1519) shows two duct systems entering the penis, one with several branches from the lower spinal cord fusing to form a duct that goes directly through to the tip of the penis, the other system going from the testes with a duct sweeping backwards to circle the bladder before returning to enter the penis (Noble 2014: 393). In the bottom left sketches, note the two channels in the penis, one for urine and one for semen, rather than a single urethra. Leonardo "labeled the spinal cord 'generative power', reflecting the Platonic view (which he later abandoned) that semen derives from the spinal marrow" (Pevsner 2002: 219). Leonardo da Vinci corrected his anatomical mistakes in a lesser-known second (probably after 1508) drawing accurately based on dissection (Noble 2014: 395).
In Ancient India, the Chinese technique of "returning the seminal essence to replenish the brain" has parallels in two associated mudras (lit. "seal; mystery; gesture")—symbolic body postures practiced in hatha yoga and kundalini. is practice of a male preserving his semen after ejaculation by drawing it up through his urethra from the vagina of a female . is a breath retention practice of rolling the tip of the tongue backwards and upwards until it touches the soft palate and reaches towards the nasal cavity [cf. Dong Xuanzi above, Wile 1992: 112]. is said to "accomplish the simultaneous immobilization of breath, thought and semen, obstructing the throat with the tongue in kumbhaka apnea, secreting copious saliva, and never emitting semen" (Needham and Lu 1983: 274).
The circa 100 BCE to 300 CE describes the posture "when the tongue enters the cavern of the cranium, moving contrawise (backward). The eye-glance penetrating between the eyebrows" and how it allows one to accomplish (Ayyangar 1938: 164).
For him (whose tongue enters) the hole (of the cranium), moving upwards beyond the uvula, whose semen does not waste away, even when he is in the embrace of a beautiful woman, as long as the semen remains firmly held in the body, so long, where is the fear of death for him? As long as the Khe-carī-mudrā is firmly adhered to, so long the semen does not flow out. Even if it should flow and reach the region of the genitals, it goes upwards, being forcibly held up by the power of the Yoni-mudrā (sanctified by the Vajroli). (Ayyangar 1938: 164-165).
The c. 150 CE describes both mudras together.
That Yogin who practices Vajrolī, he proves to be the receptacle of all psychic powers. Should he attain (that), Yoga-siddhi is on the palm of his hand. He will know what has transpired and what is yet to take place. Khe-carī will also surely be in his reach. [Vajrolī consists in plunging the glans penis in a leaden cup of cow's milk, drawing up the milk and dropping it and repeatedly practising it: then dropping the semen in the genital organ of the female and drawing it up with the ["blood; female vital energy"] discharged by her.] (Ayyangar 1938: 321).
And with the ,
the yogin should ejaculate, but after having done so he should positively regain this (the or semen emitted), and "having done so by a pumping process, the yogin must conserve it, for by the loss of the comes death, and by its retention, life." Thus we seem here to be in the presence of a veritable seminal aspiration, the muscles of the abdomen creating a partial vacuum in the bladder and so permitting the absorption of part at least of the vaginal contents (Needham and Lu 1983: 274)
The also records a marvelous side-effect of practicing semen retention, "Avoiding intercourse with women, he should earnestly betake himself to the practice of Yoga. On account of the retention of semen there will be generated an agreeable smell in the body of the Yogin." (Ayyangar 1938: 311).
It is likely that the method of perineal pressure to avoid ejaculation was also used in India. For instance, the c. 320-390 CE uses the term ("returning the semen: rerouting the semen"), which is closely analogous to Chinese (Needham and Lu 1983: 275).
The Dutch diplomat and author Robert van Gulik proposed a historical thesis that sexual mysticism or sexual yoga originated in China, rather than India as commonly assumed (1971: 339-359). The 1973 discovery of the 2nd-century BCE Mawangdui medical manuscripts (above) strengthened the probability that Daoist sexual practices, including huanjing bunao, were the precursor of Tantric sexual practices (Wile 1992: 157). Van Gulik gives Buddhist and Hindu examples of spiritual semen retention.
Some specialized Sanskrit and Pali terminology is used in the following descriptions of Hindu and Buddhist adepts visualizing semen moving up the spinal cord into the brain. Within the human body, ("life force, vital principle") energies are thought to flow through ("tubes, channels, nerves") that connect the chakra ("wheel") energy centers. There are three main nadi channels. The most important central sushumna goes along the spinal cord and connects the muladhara ("base chakra") to the sahasrara ("thousand-petalled" "crown chakra"). The left channel ida or lalana is associated with female, ova, moon, etc.; and the right channel pingala or rasana is associated with male, semen, sun, etc.
First, esoteric Vajrayana or Tantric Buddhism introduced "a highly specialized sexual mysticism, based on the principle that complete unity with the deity and supreme bliss could be achieved by a meditative process based on the coitus reservatus" (van Gulik 1971: 341). According to Giuseppe Tucci, "the disciple, through the sexual act, reproduces the creative moment. But the act must not be performed down to its natural consequences; it should be controlled by pranayama [Yogic breath-control], in such a manner that the semen goes its way backwards, not flowing downwards but ascending upwards, until it reaches the top of the head, hence to vanish into the uncreated source of the Whole" (Tucci 1949: 242).
In order to overcome the sexual dualism of the lalana and rasana nadi channels, a male Vajrayana practitioner meditates on the bodhicitta ("enlightenment-mind; thought of awakening") while having intercourse with a female partner, acquiring her female energy stimulates his bodhicitta, which blends with his activated but unejaculated semen into a new, powerful essence called bindu ("drop; dot") or "translated semen" (tr. van Gulik). The bindu breaks through the separation of lalana and rasana, and opens up a new, asexual energy channel known as avadhutika ("the cleansed one"). The bindu rises up this channel, through the chakras and reaches the crown chakra, whereupon the practitioner can purportedly achieve nirvana (van Gulik 1971: 342). Although Vajrayana incorporated older Buddhist and Hindu thought, the "conception of the coitus reservatus supplying a shortcut to complete enlightenment was an entirely new element, in that form unknown in pre-Vajrayana Buddhism" (van Gulik 1971: 343).
Second, Saikva and Sakta Tantra schools of Hindu Shaivism also practiced sexual mysticism. The process of merging the separate pingala and lalana channels, under the stimulus of real or visualized coitus reservatus with a female partner, is called Kundalini yoga. The dormant female energy in the yogi's body is called technically kundalini ("coiled snake"), which after arousal creates a new, asexual nerve channel called sushumna, along which the adept's unejaculated "translated semen" ascends until it reaches the brain. There the final union with the deity is visualized as the embrace of the god Shiva and goddess Parvati (van Gulik 1971: 343-344). In Shaktism, a practitioner who has mastered the spiritual coitus reservatus technique is called urdhvaretas ("one who can make semen flow upward [in the body]"), a practice of Brahmacarya ("celibacy"). According to Hindu concepts, a subtle form of semen exists throughout the entire body, and can be transformed into a gross form in the sexual organs (van Gulik 1971: 345). "To be urdhvaretas is not merely to prevent the emission of gross semen already formed but to prevent its formation as gross seed, and its absorption in the general system" (Woodroffe 1919: 199). Along with Chinese Daoists, the Sakta adept considered the semen his most precious possession. The 15th century Hatha Yoga Pradipika says: "He who knows Yoga should preserve his semen. For the expenditure of the latter tends to death, but there is life for him who preserves it" (Woodroffe 1919: 189). Van Gulik concludes that, "Since sexual mysticism based on the coitus reservatus flourished in China since the beginning of our era, whereas it was unknown in India, it seems obvious that this particular feature of the Vajrayana was imported into India from China, probably via Assam" (1971: 351).
Finally, Joseph Needham says a sexual ritual of the Hindu Vaishnava Sahajiya tradition has an equivalence to Chinese ("making the , or seminal essence, return") that is "too close to be accidental" (1956: 428). This method of ("Tantric sexual intercourse") involves the central nadi channel. A man and woman follow a series of postures and recitations that should result in "the passing of seminal fluid through the middle nerve, which will then go upwards towards the region of ["supreme self"]. If it passes through the other two nerves, the result will be either the procreation of children, or mere waste of energy. It is only the middle nerve which is the source of perpetual enjoyment." (Bose 1930: 71).
See also
Edging (sexual practice), maintaining long-lasting sexual arousal without reaching climax
Erotic sexual denial, the practice of refraining from sexual experiences in order to increase erotic arousal
Karezza, a term for coitus reservatus coined by Alice Bunker Stockham
Maithuna, sexual intercourse within Tantric sex, or alternatively to the specific lack of sexual fluids generated
Sarvangasana, a yogic supported shoulder stand believed to reverse the downflow loss of (bindu) life-force
Shirshasana, a yogic headstand believed to reverse the downflow loss of bindu life-force
Viparita Karani, a yogic shoulder stand believed to reverse the downflow loss of bindu life-force
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Harper, Donald (1987), "The Sexual Arts of Ancient China as Described in a Manuscript of The Second Century B.C.", Harvard Journal of Asiatic Studies 47.2: 539-593.
Harper, Donald (1998), Early Chinese Medical Literature: The Mawangdui Medical Manuscripts, Kegan Paul. [Note that the page references are to the PDF digital edition.]
Judy, Ron S. (2015), "The Semen in the Subject: Deferral of Enjoyment and the Postmodernist Taoist Ars Erotica", The Comparatist 39: 135-152.
Kroll, Paul W. (2017), A Student's Dictionary of Classical and Medieval Chinese (rev. ed.), E.J. Brill.
Little, Stephen (2000), Taoism and the Arts of China, with Shawn Eichman, Art Institute of Chicago.
Maspero, Henri (1981), Taoism and Chinese Religion, tr. by Frank A. Kierman, University of Massachusetts Press.
Needham, Joseph and Wang Ling (1956), Science and Civilisation in China: Volume 2, History of Scientific Thought, Cambridge University Press.
Needham, Joseph and Lu Gwei-Djen (1983), Science and Civilisation in China. Vol. V: Chemistry and Chemical Technology, Part 5: Spagyrical Discovery and Invention: Physiological Alchemy, Cambridge University Press.
Noble, Denis, Dario DiFrancesco, and Diego Zancani (2014), "Leonardo Da Vinci and the Origin of Semen", Notes & Records, The Royal Society Journal of the History of Science 68: 391–402.
Pevsner, Johnathan (2002), "Leonardo da Vinci’s Contributions to Neuroscience", Trends in Neurosciences 25: 217–220.
Pfister, Rodo (2022), "The sexual body techniques of early and medieval China – underlying emic theories and basic methods of a non-reproductive sexual scenario for non-same-sex partners", in Routledge Handbook of Chinese Medicine, ed. by Vivienne Lo and Michael Stanley-Baker, 337-355.
Pregadio, Fabrizio (2022), "Time in Chinese alchemy", in Routledge Handbook of Chinese Medicine, ed. by Vivienne Lo and Michael Stanley-Baker, 427-443.
Rocha, L. A. (2022), "The question of sex and modernity in China, part 1: from xing to sexual cultivation", in Routledge Handbook of Chinese Medicine, ed. by Vivienne Lo and Michael Stanley-Baker, 381-388.
Ruan, Fang Fu (1991), Sex in China: Studies in Sexology in Chinese Culture, Springer.
Schipper, Kristofer M. (1993), The Taoist Body, tr. Karen C. Duval, University of California Press.
Schipper, Kristofer and Franciscus Verellen (2004), The Taoist canon: a historical companion to the Daozang, Vol. 2 The Modern Period, University of Chicago Press.
Tucci, Giuseppe (1949), Tibetan Painted Scrolls, vol. 1, La Libreria dello Stato.
Umekawa, Sumiyo and David Dear (2018), "The Relationship between Chinese Erotic Art and the Art of the Bedchamber: A Preliminary Survey", in Imagining Chinese Medicine, ed. by Vivienne Lo et al., Brill, 215-226.
Wang Yishan (2022), "Sexing the Chinese medical body: pre-modern Chinese medicine through the lens of gender", in Routledge Handbook of Chinese Medicine, ed. by Vivienne Lo and Michael Stanley-Baker, 356-367.
Wile, Douglas (1992), Art of the Bedchamber: The Chinese Sexual Yoga Classics, Including Women's Solo Meditation Texts, State University of New York.
Woodroffe, John (1919), The serpent power: being the Ṣaṭ-cakra-nirūpana and Pādukā-pañcaka: two works on Laya-yoga, reprint Dover Publications (1974).
Sex manuals
Sexology
Sexual acts
Sexuality in China
Taoism
Taoist practices | Huanjing bunao | [
"Biology"
] | 17,047 | [
"Behavior",
"Sexual acts",
"Sexology",
"Behavioural sciences",
"Sexuality",
"Mating"
] |
74,237,264 | https://en.wikipedia.org/wiki/Pharmacological%20cardiotoxicity | Pharmacological cardiotoxicity is defined as cardiac damage that occurs under the action of a drug. This can occur both through damage of cardiac muscle as well as through alteration of the ion currents of cardiomyocytes.
Two distinct drug classes in which cardiotoxicity can occur are in anti-cancer and antiarrhythmic drugs. Anti-cancer drug classes that cause cardiotoxicity include anthracyclines, monoclonal antibodies, and antimetabolites. This form generally manifests as a progressive form of heart failure, but can also manifest as an harmful arrhythmia. In contrast, in antiarrhythmic drugs, cardiotoxicity is due to a risk of arrhythmias resulting from treated-induced ion current imbalance.
Other types of drugs are also known for cardiotoxicity, such as clozapine being associated with myocarditis.
Anticancer cardiotoxicity
The cardiotoxicity of anticancer drugs has been well documented, with an entire sub-speciality of cardio-oncology dedicated towards investigating and treating these serious side effects. Two well known anticancer drug families that cause cardiotoxicity are anthracyclines and monoclonal antibodies targeting HER2. Other types of anticancer drugs that can lead to cardiotoxicity include alkylating agents such as cyclophosphamide, BCR-ABL1 targeting receptor tyrosine kinases such as imatinib, and VEGF antibodies such as bevicizumab. This section of the article will focus on anthracyclines and HER2 monoclonal antibodies due to the prominence of cardiotoxicity in these compounds.
Pathophysiology
The mechanism of anthracycline-induced cardiotoxicity is unknown and is under active research. However, multiple theories exist. One well supported mechanism is related to the production of superoxide anion radicals that in turn damage cardiac myocytes. Recent research suggests that Top2b (topoisomerase-IIβ) helps mediate the production of oxygen radicals, representing a potential biomarker for this serious side effect. Other proposed mechanisms include interference with cardiac ATP production, mitochondria-related stress, and lipid peroxidation.
On the other hand, the mechanism of HER2 antibody cardiotoxicity is more well known. HER2 is a protein expressed on the cell membranes of HER2 positive breast cancer cells. However, HER2 is also expressed on the surface of cardiac myocytes. It is hypothesized that HER2 expressed in these cardiac cells have a cardioprotective mechanism, and the targeting of these proteins in this context leads to the cardiotoxicity associated with HER2 monoclonal antibodies.
Clinical Manifestation and Epidemiology
The cardiotoxicity of anthracyclines can be classified into three categories: early, early onset chronic, and late onset chronic. Early cardiotoxicity is rare, but manifests as arrthymias, myocarditis, and pericarditis. This type of toxicity occurs directly after treatment with anthracycline. Early onset chronic cardiotoxicity is defined as cardiotoxicity manifesting within one year of the completion of treatment, while late onset chronic cardiotoxicity occurs after one year. The cardiotoxicity of anthracyclines is dose dependent. At total exposure levels lower than 400 mg/m2, the incidence of heart failure is between 3%-5%. At a exposure rate of 700 mg/m2, the heart failure rate is at 48%.
Cardiotoxicity involving HER2 monoclonal antibodies manifests as decrease left ventricular ejection fraction and resulting heart failure. The cardiotoxicity of HER2 monoclonal antibodies is dose independent.
Treatments
The immediate intervention for the development of cardiotoxicity is discontinuation of the drug. Preventative measures for anthracycline induced cardiomyopathy include dexrazoxane, which is the only preventative drug approved by the FDA for prevention of anthracycline cardiomyopathy. Overall, there are no specific treatments targeted towards the cardiotoxicity of anticancer drugs. Rather, treatment is of the resultant heart failure. This often takes the form of ACE inhibitors or beta blockers.
Antiarrhymic cardiotoxicity
Antiarrhythmics are broad class of drugs that are used treat heart rhythm irregularities. Utilizing the Vaughan-Williams (VW) system, antiarrhymic drugs are classified into four main classes based on their mechanism of action. Class I antiarrhymics lead to blockage of sodium channels. Class II antiarrhymatics are beta-adrenoceptor blockers. Class III antiarrhymics act as potassium channel blockers, while Class IV antiarrhymics are non-dihydropyridine calcium channel blockers. While the effects of these drugs may be antiarrhymic, they can also be proarrhymic in other contexts.
Pathophysiology
The pharmacological cardiotoxicity of antiarrhymic compounds is related to their electrophysiological mechanism. In particular, because antiarrhymics drugs act on the opening/closing of ion channels, the modification of the electrical currents can lead to adverse cardiac events such torsade de pointes or ventricular fibrillation. Due to the case-by-case basis in which these medication lead to cardiotoxicity and the development of specific adverse rhythms, it has become increasingly important to assess compounds in a preclinical environment (See Pharmacological cardiotoxicity#In Silico Cardiotoxicity Assessment).
Clinical Manifestation and Epidemiology
The manifestation of antiarrhymic cardiotoxicity may manifest as worsening of the pre-existent arrhythmia or the development of a new arrhythmia.
Female sex at birth has been associated with an increased risk of the development of new arrhythmia, and other risk factors include age, kidney disease, drug-drug interactions, and other underlying heart problems.
Treatment
Like with anticancer drugs, the most common intervention for the development of cardiotoxicity is discontinuation of the causative drug. Individual risk factors, such as risk of arrhythmia re-emergence, are considered when deciding final courses of action. Adjacent devices, such as pacemakers, or ablation therapy may also be considered as alternatives to medical treatment for the primary arrhythmia.
The treatment of torsade de pointes is typically with intravenous magnesium sulfate, which helps stabilize cardiac membranes. For ventricular fibrillation cases, either/or defibrillation, amiodarone, or epinephrine is used dependent on the ACLS algorithm.
In silico cardiotoxicity assessment
Background
In the last years, in silico models have aided scientists and clinicians to cure several diseases. Computational modeling in particular has helped scientists to alter parameters that otherwise could have not been investigated.
In the field of electrophysiology, pharmacological cardiotoxicity can be carried out by leveraging specific computational models. Recently, it has become possible to analyze the pharmacological effect on atria and ventricles separately.
Since the two cardiac chambers are very different each other and play a key role both on a functional and anatomical basis, suitable computational models have to be accounted for to describe their different behavior. During the years, several models have been developed to best characterize and replicate the cellular action potential behavior of the most relevant anatomical region of the heart, such as Courtemanche model for atria or O'Hara model for ventricles.
Creation of a population of cellular action potentials
In this way, it has been possible to create a virtual cellular population of cardiomyocytes and vary their conductances that are related to the main ionic currents which contribute to the action potential morphology, and is reflective of a specific anatomical region of the heart.
In order to create a stable population of cellular action potentials, several biomarkers have been developed to best characterize the instability of cellular action potentials. Examples of biomarkers reported include:
APD90: it represents the action potential duration when the phase of the repolarization is at 90%, so it is possible to associate to this value a time and it can be expressed as:
APD90: it represents the action potential duration when the phase of the repolarization is at 50%, so it is possible to associate to this value a time and it can be expressed as:
APD20: it represents the action potential duration when the phase of the repolarization is at 20%, so it is possible to associate to this value a time and it can be expressed as:
Triangulation: it is a measure of how triangular is an action potential, expressed as:
APA: it represents the action potential amplitude, expressed as:
Regional clusterization
Once the cellular population is stable, all action potential are then compared to physiological data related to the most relevant anatomical regions to appropriately filter the action potential, aiming to consider just the physiologically relevant ones.
At the atrial level, clusterization occurs with data associated to:
Right atrium
Right atrial appendage
Left atrium
Left atrial appendage
Atrioventricular rings
Crista terminalis
Right Bachmann's bundle
Left Bachmann's bundle
Pectinate muscles
Simulation of the pharmacological action
According to pharmacokinetic and pharmacodynamic ideals, pharmacological action is integrated in the model. By means of specific electrical stimuli protocols, the pharmacological effect of a new drug can be investigated in a completely safe, and controlled computational environment, providing preliminary important considerations concerning the cardiotoxicity of new pharmacological compounds.
According to the outcome of the simulations, several aspects can be investigated to identify the proarrhythmicity of a new pharmacological compound. The typical changes, known as repolarization abnormalities, that are considered pro-arrhythmic include:
Early afterdepolarization
Electrical alternans
Repolarization failures
Torsade de point risk score
Simulation can be carried out at different effective plasmatic therapeutic level of the drugs to identify the level at which cardiotoxicity cannot be neglected. The data collected could be finally managed to create a score system aimed to define the torsadogenic risk, namely the risk of inducing torsade de pointes, of the new drugs.
A possible torsade de point risk score to assess cardiotoxicity could be:
where is the sum of all concentrations, [C] is the concentration taken into account, , is the total number of models in the population, and represents the number of models showing repolarization abnormalities.
Tissue simulations
More detailed computation simulations can be carried out accounting for not cellular models, but taking into consideration the functional syncytium and enabling the cells to mutually interact, the so-called electrotonic coupling.
In case of tissue simulation or in wider cases, such as in whole organ simulations, all the cellular models are note applicable anymore, and several corrections have to be made. Firstly, the governing equations can not be just ordinary differential equations, but a system of partial differential equations has to be accounted for. A suitable choice may be the monodomain model:
where is the effective conductivity tensor, is the capacitance of the cellular membrane, the transmembrane ionic current, and are the domain of interest and its boundary, respectively, with the outward boundary of .
See also
Arrhythmias
Cardiology
Electrophysiology
Pharmacology
References
External links
American Heart Association
Food and Drug Administration
European-Heart-Rhythm-Association
Cardiotoxins
Pharmacology
Toxicology
Electrophysiology | Pharmacological cardiotoxicity | [
"Chemistry",
"Environmental_science"
] | 2,508 | [
"Pharmacology",
"Toxicology",
"Medicinal chemistry"
] |
74,242,366 | https://en.wikipedia.org/wiki/Athene%20cunicularia%20arubensis | Athene cunicularia arubensis, also known as the Aruban burrowing owl or shoco, is an endemic subspecies of burrowing owl in Aruba. Since 2015, the shoco has become a national symbol of Aruba.
Taxonomy
In the IOC World Bird List, the subspecies A. c. arubensis is no longer listed separately but has been merged with the subspecies A. c. brachyptera.
Characteristics
The shoco has a head-to-tail length of centimeters. Notable features include large round yellow eyes, prominent whitish eyebrows, absent ear tufts, and relatively long gray legs.
Distribution
Based on behavior and vocalizations, it is believed that the shoco is most likely a distinct and separate species of owl. Furthermore, it is suspected that the shoco has been present on Aruba for at least over one and a half million years. Aruba is the only country within the Kingdom of the Netherlands that has a burrowing owl.
Lifestyle and status
The shoco lives in burrows on the ground in areas with low cactus vegetation and dry forests.
If the shoco cannot find a burrow, it will dig one itself in soft ground. Since much of the life history of this subspecies is still unknown, the population is being monitored within the protected area of Arikok National Park.
The shoco has been designated as an endangered species and enjoys legal protection. Despite its popularity, the well-being and survival of the burrowing owl are under great pressure. In the first two decades of the 21st century, the Aruban population grew, along with population density. With 636 persons per square kilometer in 2017, it even exceeded the density of the Netherlands. As a result, the habitat of the shoco is severely limited and fragmented. Furthermore, the unregulated and extreme increase in tourist off-road recreation and the presence of the exotic boa constrictor pose a threat to the survival of the shoco. In 2013, the size of the population was estimated to be less than 200 breeding pairs.
Breeding
The burrow also serves as a nesting site. The shoco lays 1 or 2 eggs every other day until all the eggs are laid. A shoco can lay up to 4 eggs, which are incubated for 3–4 weeks. The young owlets are cared for 3 months until they leave the nest. Burrowing owls typically lay three to six eggs, which are incubated for 28 days and hatch after 42 days. It is unclear whether this also applies to the shoco.
Feed
The diet primarily consists of mice, lizards, and large insects, including beetles and grasshoppers. From there, it begins its hunt from the ground, walking, hopping, or running. It also hunts for prey from a high perch and captures it with its feet. The shoco is active during the day but becomes more active in hunting during the late afternoon and evening. These owls have excellent vision in the dark and possess keen hearing abilities.
National symbol
The shoco is the native species most associated with Aruba. It is an integral part of the local culture and has traditionally served as a symbol of wisdom and knowledge. In 2015, the shoco was officially designated as the national symbol of Aruba, although it had been fulfilling this role since 2012. Since 2017, Aruba also has a national bird: the prikichi or Brown-throated parakeet (Aratinga pertinax arubensis). Out of the 270 bird species registered for Aruba, these two are found exclusively on the island.
The image of the shoco is well known in Aruba. In 1990, a series of banknotes featuring animals was put into circulation, including the 50 Aruban florin banknote with an image of the shoco. In 1994, four postage stamps were issued depicting the shoco and the emblem of the World Wildlife Fund. In 2012, the Central Bank of Aruba issued a commemorative silver 5-florin coin featuring the Aruban shoco. The coin was equipped with augmented reality by the Royal Dutch Mint, allowing people to scan the coin with a smartphone to access additional information about the coin and the shoco. Additionally, two children's books have been published in which the shoco plays the main role: Shon Shoco weet raad ("Mr. Shoco knows best") (2005) by Jacques Thönissen and / ("The call of the shoco") (2014) by Charlotte Doornhein. The latter is a bilingual gift book specially written for the Aruban Children's Festival.
References
Fauna of the Neotropical realm
Symbols
cunicularia arubensis
Endemic fauna of Aruba | Athene cunicularia arubensis | [
"Mathematics"
] | 961 | [
"Symbols"
] |
74,242,529 | https://en.wikipedia.org/wiki/HD%2088231 | HD 88231, also known as HR 3993, is a solitary orange-hued star located in the northern constellation Leo Minor. It has an apparent magnitude of 5.84, making it faintly visible to the naked eye under ideal conditions. Gaia DR3 parallax measurements imply a distance of about 569 light-years, and the object is currently receding with a heliocentric radial velocity of . At its current distance, HD 88231's brightness is diminished by 0.17 magnitudes due to interstellar extinction and it has an absolute magnitude of −0.59.
The object has a stellar classification of K3 III, indicating that it is an evolved red giant star. It has a comparable mass to the Sun but it has expanded to 24.9 times the radius of the Sun. It radiates 228 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of . HD 88231 is slightly metal enriched with an iron abundance 112% that of the Sun ([Fe/H] = +0.05).
HD 88231 was suspected to be variable in the K-band based on Two-Micron Sky Survey observations in 1969. A 1994 paper found that it ranges from 5.79 to 5.88 in the visual band. As of 2004 however, the variability has not been confirmed.
References
K-type giants
Suspected variables
Leo Minor
BD+38 02110
088231
049893
3993 | HD 88231 | [
"Astronomy"
] | 311 | [
"Leo Minor",
"Constellations"
] |
74,243,673 | https://en.wikipedia.org/wiki/Retatrutide | Retatrutide (LY-3437943) is an experimental drug for obesity developed by American pharmaceutical company Eli Lilly and Company. It is a triple glucagon hormone receptor agonist (GLP-1, GIP, and GCGR receptors). It has been shown to achieve a more than 17.5% mean weight reduction in adults without diabetes but with obesity or preobesity (overweight) during a phase 2 trial.
Chemistry
The drug is a peptide with amino acid sequence
YA¹QGTFTSDYSIL²LDKK⁴AQA¹AFIEYLLEGGPSSGAPPPS³
where superscript numbers refer to unique chemical modifications:
"A¹" refers to 2-aminoisobutyric acid (AiB) instead of alanine.
"L²" refers to alpha-methyl added to leucine (MeL, 2-methylleucine).
"S³" refers to addition of an amino group to the C-terminal serine.
"K⁴" refers to a modification group attached to the lysine's tail amine, specifically (AEEA)-gamma-Glu-C20 diacid.
References
GLP-1 receptor agonists
Peptide therapeutics
GIP receptor agonists
Glucagon receptor agonists | Retatrutide | [
"Chemistry"
] | 272 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
74,250,587 | https://en.wikipedia.org/wiki/455-line%20television%20system | The 455-line standard, also known as 450-line, was a French black-and-white analog television broadcasting norm employed between 1937 and 1939. It was later replaced by the 441-line format, which remained in use until 1956.
Historical Background
In 1931, in Paris, Georges Mandel, the Minister of Posts, provided support to the Compagnie des Compteurs (CdC) in conducting mechanical television experiments. Engineer René Barthélémy was granted a studio on Rue de Grenelle, Paris for this purpose. The resolution gradually increased from 30 to 60 lines and then to 180 lines by 1935, and the transmitter was located to the Eiffel Tower.
Robert Jardillier, the next Minister of Posts, launched in 1936 a call for tenders to provide television with higher definition, based on the iconoscope and electronic television. A test period would follow and enable the best standard to be chosen.
Broadcasts became regular from January 4, 1937, from 11 to 11:30 am and 8 to 8:30 pm on weekdays and from 5:30 pm to 7:30 pm on Sundays. Grammont performed its tests in 441 lines, the Compagnie Française de Télévision in 450 lines, and Thomson-Houston in 455 lines.
In July 1937, the administration chose the 455-line system designed by Thomson-Houston, followed by public demonstrations at the International Exposition of Art and Technology in Modern Life.
Broadcasts using the previous mechanical system continued alongside the new electronic system until April 10, 1938.
In July 1938, a decree of the Posts, Telegraphs, and Telephones Agency defined the French terrestrial television standard as transmitting on 455 lines VHF (46 MHz, positive visual modulation, 25 frames per second), to be adopted throughout France within three years. 455-line TV sets from brands like Pathe-Marconi, Philips, Radioindustrie, CdC, Grammont, and Emyradio began to be sold to the public.
In 1938, the transmitter, located at the Eiffel Tower, changed to this 455-line format, making it the most advanced and powerful broadcasting system in the world, boasting a transmission power of 30 kW. Radiodiffusion Nationale (RN Télévision) starts its broadcasts from Paris, and expansion for other cities like Lyon, Marseille and Bordeaux is planned. In the spring of 1939, tests are conducted in Lille.
The Rue de Grenelle studio closed on July 31, 1939, and after this point, Radiodiffusion Nationale only broadcast films, documentaries, and recorded news using telecine.
When France entered World War II on September 3, 1939, the military authorities ordered the cessation of broadcasts and took control of the Eiffel Tower transmitter. A few broadcasts were still broadcast episodically for transmitter maintenance purposes.
On June 6, 1940, the French Resistance took action to sabotage this equipment to prevent its use by the Nazis. However, in 1942, the occupying forces decided to repatriate the equipment for their Berlin station and replaced it with 441-line equipment.
References
See also
TF1
Television technology | 455-line television system | [
"Technology"
] | 638 | [
"Information and communications technology",
"Television technology"
] |
74,253,727 | https://en.wikipedia.org/wiki/Urban%20retrofitting | Urban retrofitting is a combination of policies and phenomena done with the goal of undoing or remedying the effects of urban sprawl. The phenomena of adaptive reuse and infill development to combat sprawl are key to this. It often follows the new urbanist school of thought, which aims to undo the sprawl and flight from urbanized areas that occurred in the US and Canada after WWII.
History and issues to solve
Ellen Dunham-Jones and June Williamson, professors of urban planning and architecture at Georgia Tech and CUNY, respectively, wrote the book on this phenomenon. Much of their work is captured in their book, "Retrofitting Suburbia: Urban Design Solutions for Redesigning Suburbs which discusses the phenomena of urban sprawl, economic development, climate change mitigation, and environmental justice.
In short, there are several issues that modern society faces that are either caused by or exacerbated by car dependency. These challenges include, but are not limited to: disrupting automobile dependence to promote public transit,
"improve public health, support an aging population, leverage social capital for equity, compete for jobs, and add water and energy resilience" per the Congress for New Urbanism.
Solutions to sprawl and effects
This phenomenon uses underutilized lots, parking lots, greyfield lots, densification of land use especially in regard to residential density, and rezoning to encourage walkability.
In a case study of the Belmar neighborhood of Lakewood, Colorado of the former Villa Italia Mall, the retrofit of the property resulted in the following:
22 city blocks on 103 acres
777,000 square feet of retail space
868,000 square feet of office space
190,000 square feet of hotel space
1,048 housing units
9 acres of public parks/plazas
5,000 parking spaces (garage, surface and street)
There are several other cases of successful retrofits, including downtown Silver Spring, Maryland; North Hills in Raleigh, North Carolina; and CityCentre in Houston, Texas.
See also
Urban sprawl
Infill
Walkability
Zoning
Mixed-use development
Sunk cost
Green retrofit
Gentrification
Urban renewal
Urban decay
Cost of poverty
References
Urban planning
Repurposing | Urban retrofitting | [
"Engineering"
] | 460 | [
"Urban planning",
"Architecture"
] |
74,258,532 | https://en.wikipedia.org/wiki/2023%20Boksburg%20gas%20leak | On 5 July 2023, a gas leak killed 17 people, including three children, in Boksburg, Ekurhuleni, Gauteng, South Africa. Ten other people were hospitalised.
Incident
Seventeen individuals, including women and children, died when suspected nitric oxide escaped from a gas cylinder that was being prepared for use in an illegal gold mining operation. Ten others were hospitalized. Illegal gold miners, commonly referred to as "zama zamas", operate in abandoned mine shafts and use the empty gas cylinders, known as "phendukas", to process the stolen ore. The cylinders, often stolen, are first drained of gas, then cut open so that ore can be placed in them along with a steel ball which crushes the ore as the cylinder is rotated.
The gas escaped within the densely populated Angelo shanty town in Boksburg. The victims were found within a radius of 100 meters (328 feet) from the leak.
Response
Emergency services, including forensic investigators and pathologists, and search and rescue services worked in the area to determine the casualties. Emergency service officials expected to discover additional bodies. Twelve individuals underwent medical treatment, while one individual remained in critical condition.
References
2023 disasters in South Africa
2023 mining disasters
2020s in Johannesburg
July 2023 events in South Africa
Gas explosions
Mining disasters in South Africa | 2023 Boksburg gas leak | [
"Chemistry"
] | 273 | [
"Natural gas safety",
"Gas explosions"
] |
72,765,366 | https://en.wikipedia.org/wiki/Buchwaldoboletus%20xylophilus | Buchwaldoboletus xylophilus is a species of bolete fungus in the family Boletaceae native to Asia, found on wood. It has a convex brown cap, and a red-brown stipe. Its edibility is unknown.
Taxonomy and naming
Originally described by Thomas Petch in 1922 as Boletus xylophilus, it was given its current name by Ernst Both and Beatriz Ortiz-Santana in A preliminary survey of the genus Buchwaldoboletus, published in "Bulletin of the Buffalo Society of Natural Sciences" in 2011.
Description
The cap is convex, and its surface is dry to subviscid, and "minutely velvety". Its color is ferrugineous brown. Easily peeled off the mushroom, the soft brown skin is separated from the flesh by a thin gelatinous layer. The pores are small and angular, and the pore surface stains blue with injury. The stipe is red-brown, and there is a yellow mycelium at the stipe base.
Spores are ellipsoid, smooth, and measure 4.5–5.5 by 3.2–4 μm.
Distribution
Buchwaldoboletus xylophilus has been recorded across Asia throughout Malaysia, Sri Lanka, Hong Kong, and Philippines
References
External links
Boletaceae
Fungi described in 1922
Fungi of Asia
Fungus species | Buchwaldoboletus xylophilus | [
"Biology"
] | 288 | [
"Fungi",
"Fungus species"
] |
72,765,742 | https://en.wikipedia.org/wiki/Talim%20%28textiles%29 | Talim (Kashmiri: تعليم, , , , ) in textiles is a symbolic code and system of notation that facilitates the creation of intricate patterns in fabrics, such as shawls and carpets, and the written coded plans that include colour schemes and weaving instructions. The term is used in traditional hand-weaving in the Indian subcontinent. Talim was initially used to create certain types of patterns in Kashmiri shawls, and later came to be applied in the
production of carpets.
Etymology and origin
The term talim, which refers to a symbolic code and system of notation used by shawl and carpet artisans in their weaving processes, came to the Urdu language from the Arabic noun taʻlim (), which means "authoritative instruction", "teaching", or "edification". It means the same in Urdu and Kashmiri. The Arabic noun originated from the second form of the Arabic root verb ʻalima (), which means "to know".
According to a local belief in Kashmir, talim was introduced to them by Persian scholar and Sufi Muslim saint Mir Sayyid Ali Hamadani. The belief notwithstanding, talim might have originated from Kashmir; Amritsar was the only place outside of Srinagar where talim was used, by migrated Kashmiri artisans.
Technique
Whereas carpets are generally woven horizontally, providing weavers with a clear view of the progress they are making in creating designs, in Kashmir, carpets are woven vertically, so the weaver is reliant on the talim.
The talim technique forms fabrics by passing the weft thread as per a given script that has design codes. Weavers use talim to weave the desired pattern with planned colours. Talim involves teamwork when applying the technique, as the process of creating intricate fabric designs in weaving begins with the (designer, who designs using pencils on graphs) meticulously crafting the design on a blank sheet of paper called a , and the master, , making the colour codes and symbols for weft yarns that would interlace the warp to construct the desired design. He writes on a long strip of paper, in specific symbols, the colour codes, and the number of knots to be woven with each colour. collaborates with talim guru and is known as the artisan responsible for determining the colours. is a process or the act of "picking the codes" from the graph. A clerk called the would record the step-by-step instructions for these numbers and colours, and thousands of low-paid and interchangeable weavers would read or recite the record to carry out the design. Afterward, a copyist makes copies, which are needed when multiple looms weave the same product.
The script, which has been encoded, is deciphered and translated according to the specific guidelines of weavers in order to incorporate the design that is included within it. Talim has been compared to "hieroglyphics" or as a "notational-cum-cryptographic system", as it is challenging to decipher and is unique to the shawls of Kashmir, which requires expertise to comprehend. According to researcher Gagan Deep Kaur, "The talim is widely held to be a trade secret of the community and has always been fiercely guarded by the owners." Those who use talim for shawl-making do not assign important tasks to women, because of the fear that the technique and knowledge may be divulged to other communities when the women are sent there to be married.
The coded cards known as talim in the Kashmiri language were used for creating certain types of patterns in shawl weaving. The talim technique is employed in the creation of kani shawls, which originated from the Kanihama region of the Kashmir valley. Carpet weaving adapted the technique from shawl making. When Kashmiri artisans started to create carpets, they chose to continue using the talim rather than switching to a different method. The resurgence of the carpet industry in Amritsar during the last century resulted in the prevalent use of the talim technique among the local weavers, a majority of whom hailed from the region of Kashmir.
Recitation of codes
Talim was also communicated through recitation accompanied by a melodic chant or song. In traditional weaving practices, the use of chanting was common. The movement of the shuttles was synchronised with the song of the weaver, adding a musical rhythm to the instructions represented through hieroglyphics. The weaver's chant, "Two blue, one red, three yellow, two blue," served as a guide as they wove and replicated the designated pattern.
Usage
The first factories established in Amritsar around 1860 utilised Bokhara designs. However, Kashmiri weavers maintained their traditional techniques and employed the talim, instead of a cartoon, for tying knots. As a result, Amritsar became the second location in the Indian subcontinent to use the talim.
The traditional weaving practices are still carried out in some parts of the Indian subcontinent. The exact date when talim was last used in the subcontinent varies depending on the region and the specific weaving community. Indian textile historian Jasleen Dhamija wrote in her book Handwoven Fabrics of India that there were still some weavers in the Kashmiri village of Kanihama who applied talim in weaving shawls.
, the carpet weavers in Kashmir were the only remaining users of talim in carpets, according to Zubair Ahmed, director of the Indian Institute of Carpet Technology. The institute aims to preserve traditional Kashmiri carpet designs by digitising talim and training weavers in the technique.
Gallery
References
Culture of Kashmir
Textile techniques
Weaving
Trade secrets
Textile design
Textile patterns | Talim (textiles) | [
"Engineering"
] | 1,163 | [
"Textile design",
"Design"
] |
72,765,934 | https://en.wikipedia.org/wiki/Sarmentosin | Sarmentosin is a glycoside and that is found in several plant species, notably Ribes nigrum (blackcurrants) and Sedum sarmentosum.
Chemical structure
Sarmentosin has a molecular formula of C₁₁H₁₇NO₇ and a molecular weight of 275.25 g/mol. Its IUPAC name is (E)-2-(hydroxymethyl)-4-[(2R,3R,4S,5S,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxybut-2-enenitrile.
Sources
Sarmentosin can be extracted from plants in the Rhodiola genus and blackcurrants. Recent studies have specifically identified sarmentosin as a key bioactive compound in blackcurrants that contributes to its monoamine oxidase inhibitory effects.
Ecology
At least two Parnassius butterflies, Parnassius apollo and Parnassius smintheus, sequester sarmentosin and other hydroxynitrile glucosides in their bodies from the Sedum plants they eat.
References
Glycosides
Nitriles
Alcohols
Monoamine oxidase inhibitors | Sarmentosin | [
"Chemistry"
] | 270 | [
"Carbohydrates",
"Glycosides",
"Functional groups",
"Biomolecules",
"Glycobiology",
"Nitriles"
] |
72,766,444 | https://en.wikipedia.org/wiki/Buchwaldoboletus%20kivuensis | Buchwaldoboletus kivuensis is a species of bolete fungus in the family Boletaceae native to Africa.
Taxonomy and naming
Originally described by Paul Heinemann in 1951 as Gyrodon lignicola, it was given its current name by Ernst Both and Beatriz Ortiz-Santana in A preliminary survey of the genus Buchwaldoboletus, published in "Bulletin of the Buffalo Society of Natural Sciences" in 2011.
Description
The cap is convex, tomentose-pulverulent and dry. Its color is cinnamon-brown. Easily peeled off the mushroom, the skin is separated from the flesh by a thin gelatinous layer. The pores are small and angular, ochraceous-decurrent, and the pore surface stains blue with injury. The stipe is cylindrical and eccentric, and there is a yellow mycelium at the stipe base.
Spores measure 5.3–6.8 by 3.3–4.7 μm.
Distribution
Buchwaldoboletus kivuensis has been recorded in Congo, in the region of lakes Edward and Kivu, at altitude 1650 m. It grows on soil covered with dry branches and on Coffea arabica and Eucalyptus plantations.
References
External links
Boletaceae
Fungi described in 1951
Fungi of Africa
Fungus species | Buchwaldoboletus kivuensis | [
"Biology"
] | 268 | [
"Fungi",
"Fungus species"
] |
72,766,586 | https://en.wikipedia.org/wiki/Hunting%20success | In ecology, hunting success is the proportion of hunts initiated by a predatory organism that end in success. Hunting success is determined by a number of factors such as the features of the predator, timing, different age classes, conditions for hunting, experience, and physical capabilities. Predators selectively target certain categories of prey, in particular prey of a certain size. Prey animals that are in poor health are targeted and this contributes to the predator's hunting success. Different predation strategies can also contribute to hunting success, for example, hunting in groups gives predators an advantage over a solitary predator, and pack hunters like lions can kill animals that are too powerful for a solitary predator to overcome.
Similar to hunting success, kill rates are the number of animals an individual predator kills per time unit. Hunting success rate focuses on the percentage of successful hunts. Hunting success is also measured in humans, but due to their unnaturally high hunting success, human hunters can have a big effect on prey population and behaviour, especially in areas lacking natural predators, recreational hunting can have inferences for wildlife populations.
Definition
Predators may actively seek out prey, if the predator spots its preferred target it would decide whether to attack or continue searching, and success ultimately depends on a number of factors. Predators may deploy a variety of hunting methods such as ambush, ballistic interception, pack hunting or pursuit predation. Hunting success is used to measure a predator's success rate against a species of prey or against all prey species in its diet, for example in the Mweya area of Queen Elizabeth National Park, lions had a hunting success of 54% against African buffaloes and 35.7% against common warthogs, though their overall hunting success was only 27.9%.
Hunting success across the animal kingdom vary from 5–97% and hunting success can greatly differ between different populations of the same species. Hunting success can be measured for predators in different trophic levels. Hunting success rate is the percentage of captures in a number of initiated hunts, for example, 1 in 2 to 20 tiger hunts are guessed to end in success, which means tigers are guessed to have a hunting success rate of between 5–50%. Percentage is the preferred method used to write hunting success rather than raw numbers. Usually a single study is used to represent the hunting success of an entire species or in some cases estimations are used.
Hunting success can also be used to define the number of kills a human hunter makes over a specific number of hunts. However, hunting success is not used to define the number of animals a poacher, or a canned trophy hunter kills.
Hunting success in animals
Detailed field studies show that prey are usually successful at escaping predators, with hunting success rates as low as 1–5% in many systems. The result of a predatory attack largest depends on the interaction between the predator's physical performance and any evasive maneuvers by the prey animal.
List of animals by hunting success rate
Reasons for high hunting success
Most mammals have a hunting success below 50% but some mammals such as African wild dogs and harbour porpoises can have hunting success rates of over 90%. The African wild dog is one of the most effective hunters on earth, with hunting success reaching a maximum of 90%. Their high levels of hunting success is due to their highly co-operative hunting behaviour accompanied with high stamina. Wild dogs typically use their stamina to exhaust their prey, which are usually caught after a chase lasting an average of . The wild dog's stamina and the prey animal's exhaustion are the driving factors that cause most successful hunts. Harbour porpoises are not usually social but on multiple occasions they've been recorded hunting cooperatively. The average group size consists of about two individuals. Using echolocation, they locate prey and capture them. They continuously forage throughout the day and night to meet their body requirements. It is hypothesized that harbour porpoises eat large amounts of food, about 10% of their own body mass. Another theory suggests that harbour porpoises require relatively large energy-rich prey, with high hunting success rates to meet their estimated metabolic requirements.
Dragonflies have the highest observed hunting success of any animal, with success rates as high as 97%. They are also opportunistic and pursue a variety of prey. Predatory performance may have consequences in terms of energetics, mortality and potential loss of feeding or mating territories. The reason for their hunting success is due to many unique evolutionary adaptations, which includes aspects of eyesight and flight. In terms of flight, dragonflies can independently control their fore and hind wings, they can also hover and fly in any direction, including backwards. They can fixate on their prey and predict its next move, catching it midair with extreme accuracy. Each of a dragonfly's eyes is made up of thousands of units known as ommatidia that run across its head. This gives them almost 360-degree-vision, which helps them spot prey more efficiently.
The black-footed cat has the highest hunting success of any member of family Felidae. In 1993, a female and male were observed for 622 hours, a kill was made every 50 minutes and they had a hunting success of 60%. A total of 550 animals were consumed. About 14 small animals were caught each night. Their hunting success is due to their hunting behaviour and frequency of initiated hunts. They use three different ways of hunting, which includes "fast hunting", "slow hunting" and "sit and wait" hunt. They use these three hunting strategies to ambush or pursue their prey which mostly includes small mammals, insects and small birds.
Kill rates
Kill rates is the number of prey or biomass killed by an individual predator per unit time. A predator's functional response refers to how kill rates vary with prey density and are of central importance when predicting the stability threshold for prey populations under the effects of predation, and also estimate the potential carrying capacity of the populations of predators. Kill rates and functional responses are both influenced by diverse ecological variables. Kill rates differ between males and females, solitary individuals, social individuals, mothers with cubs, different age classes, individual fitness, prey availability, experience, etc.
Kill rates are required to further understand functional responses and predator-prey dynamics, as well as develop conservation strategies for predator species around the world. Kill rate studies have been conducted for large carnivores such as gray wolves, jaguars, tigers and leopards. A kill rate study of cougars showed that females with cubs had the highest kill rate, with one adult female with cubs in northern California having a kill rate of 2.35 ungulates per week. Adult males averaged 0.84 ungulates per week, females with cubs had an average of 1.24 ungulates per week and solitary females had a mean kill rate of 0.99 ungulates per week.
Factors influencing success
Selective feeding
Hunting success depends on the distance or time the predator has to catch its prey, comparable to the distance (time) that the prey has to escape. In the wild, a discrepancy is observed between the carnivore's low hunting success and highly selective predation on ill animals. This behaviour may be described by the co-adaptive evolution of predator and prey. A predator like a wolf cannot always hunt a given deer, because an error in prey choice can lead to energy loss, injury and even death. Predators tend to seek vulnerable prey, and this is the basis of the selective impact of predators on the population of prey species. The low hunting success rate of wild carnivores, may be due to the fact that identification of potentially vulnerable prey from distance is imperfect, the more so that the behaviour of prey compensate for its poor health. In the wild, the capacity for distinguishing odors or a slight difference in prey behaviour are influenced by a number of factors, such as wind strength and direction, the body condition and features of the predator, its experience, conditions for pursuing prey and much more. The microbiota (metabolites at the surface of the body) in animals exposed to long-term stress are responsible for their specific stress odor, this allows predators to evaluate the vulnerability of its potential prey. The causes of reduced health differs and depends on the individual animal's sensitivity to several biotic and abiotic factors such as endogenous, infectious, and parasitic diseases, intra- and interspecific interactions, etc. The host macro-organism, which is the microflora system helps predators to judge the state of its prey.
Social and solitary predators
Increased hunting success is a frequently cited benefit of group living in social predators and this is also a hypothesis for the evolution of sociality. However, previous research shows that the benefit of increased hunting success is only present in small groups. In several group hunting taxas, ranging from insects to primates, despite the cooperation among the hunters, the hunting success of the larger group size does not increase. Research shows that predator groups of 2–5 animals have the highest hunting success rates, then levels off, or even declines, across larger groups. It has been theorised that the hunting success of predators hunting formidable prey increases with group size. This pattern is caused by the increased cooperation in large groups due to the much lower chance a solitary predator has against such prey. The low hunting success of solitary predators promotes cooperation because an extra hunter can sufficiently improve group hunting success to avoid the risk of injury and energy loss.
Hunting methods
Field studies show that different predator hunting methods (ambush, pursuit predation, etc.) can lead to distinct number of individuals or prey captured. Due to this, predators with different hunting strategies can cause competing trophic cascades and function at different trophic levels. Predators are often classified as active or sit-and-wait predators by their average hunting behaviour. The locomotor crossover hypothesis states that ambush predators should have more success when hunting fast-moving prey, whereas cursorial predators should be more successful when hunting sedentary prey. Studies reveal that starvation can cause an ambush predator to adopt a pursuit predation hunting method, though ambush predators regularly switch to pursuit predation when prey densities are lower. Experiments show that differences in prey's anti-predator responses to the environment can influence predator behaviour or success. Field observations show that predators can alter their hunting behaviour at larger scales according to prey behaviour, but at smaller scales they seek specific locations where they can facilitate hunting.
Environmental influences
Conditions in the environment have an influence on a predator's ability to detect prey and vice versa. A primary mechanism is the limiting of foraging time obtained by mobile predators due to the risk of unfavourable conditions. The importance of predators on community functioning in gentle environments, an effect which reduces in stressful situations. Hydrodynamic stress associated with waves decreases the predator's success, as these conditions restrict predator mobility and foraging activity. Environmental conditions may impair a predator's ability to find or consume prey. For instance, green crab predation drastically decreased in the vicinity of the Damariscotta River with high flow celerities, though they were found at greater densities in high flow rates. Similar incidents happened when fish, insects and copepods exhibited much lower foraging success in more rapid flows. As a result, environmental conditions can influence predators by reducing their ability to find or handle prey. Behavioural research shows that environmental conditions like hydrodynamics can have a big effect in systems where predators rely on chemical cues to find their prey.
Vegetative cover
A predator's hunting behaviour is suited for hunting in specific types of vegetative cover and is thus a largely custom characteristic in taxonomic families. Felids for instance typically use dense cover to stalk or ambush prey, whereas canids do not use vegetative cover when hunting. Sympatric predators like the Canada lynx and the coyote were tracked in the snow for three seasonal winters and hunting behaviour in relation to vegetative cover was studied. The main prey for both species were snowshoe hares, the lynx pursued hares more frequently in sparse white spruce canopies than coyotes, on the other hand coyotes pursued hares more in dense spruce than lynxes. It is thought that the hunting behaviour of lynxes varies according to cover, while that of coyotes is fixed. However, coyotes appeared to use cover to their advantage when stalking hares, possibly an influence of snow on the hunting methods of each of the predator species.
In human hunters
Hunting success in humans
Hunting success in humans differ in methods used, selected prey, the performance of the hunter, weather conditions, etc. A study showed that hunters who used dogs had a hunting success of 60%, while those who employed persistent hunting had a hunting success of 37–100% over 15 attempted hunts. Hunters who hunted with bows and arrows had a hunting success of only 5%, whereas others who hunted with springhare probe had a hunting success of 14% and yet others who used clubs and spears had a success rate of 45%. The study was based on the hunting methods of the bushmen in southern Africa.
Factors influencing success of human hunters
In Kentucky, US, a study was conducted about the factors influencing the flush and hunting success of hunters in three game species which were ruffed grouse, northern bobwhite and the cottontail rabbit. Encounter rates may have effects on population dynamics, hunter satisfaction, and hunter retention. In a 12-year span between 2003 and 2015, there were about 3,948 grouse hunts, 19,301 rabbit hunts, and 4,798 bobwhite hunts took place. In this case, hunting success was defined as the number of animals a hunting party flushed out. Hunting success was expected to increase over the hunting season due to cover being reduced and weather being more hospitable for upland hunting. Hunting was usually enhanced when more hunters and dogs were introduced to hunting parties.
Hunting types and methods
There are many types of hunting that human hunters employ, these types include recreational hunting (e.g. trophy hunting), medium/small game hunting (e.g. deer hunting), fowling, pest control/nuisance management, commercial hunting (e.g. whaling) and poaching. In terms of hunting methods 24 methods are used. This methods include baiting (i.e. the use of baits to lure animals), battue (i.e. scaring animals into a killing zone), beagling (i.e. using beagles in hunts), the use of camouflage to hunt, shooting, the use of dogs, persistence hunting (i.e. use of stamina to exhaust prey), stalking and much more. Modern regulations differentiate between lawful hunting and illegal poaching, where uncontrolled hunting of animals occur.
Historical, substinence, and sport hunting can greatly differ, with modern hunting regulations addressing the issues of hunting and the most sustainable way to hunt. Techniques vary between government regulations, a hunter's personal ethics, local practices, hunting equipment, and the target animal species. Hunters may use a combined of two or more hunting techniques, though law may forbid hunters from using techniques common in activities like poaching and wildlife management.
Impact
The exploitation of animal species currently threatens many species with extinction. Particularly in tropical rainforests, where hunting for food poses the most severe threat to many species in tropical rainforests. In some cases, Piro shortgun hunters took a limited number of shotgun cartridges on hunting trips, and they usually pay no attention to less profitable prey early in the trip, when the chance for more profitable prey becomes more likely. Human disturbance can influence the behaviour of wild animals, which can have inferences for wildlife populations. For example, in Northeastern Gabon, studies show that hunting and human disturbance decreased the population of large mammals near roads and in more populated areas. In particular, primates like chimpanzees and mandrills were found far from the roads, this could possibly be due to more intense hunting of these species for either bushmeat or in retaliation for crop raiding. Most large predators have been extirpated from the range of the white-tailed deer, so hunters have now taken this predatory role. Hunters can indirectly affect prey species, indirect behavioural responses includes altered selection of resource, space use or movement. Deers realize that humans are a threat and adapt behavioural strategies by minimizing movement and showing high resistancy times in established ranges, factors that influence harvest susceptibility.
See also
Pursuit predation
Pack hunting
Trophic level
Anti-predator adaptation
References
Hunting
Ecology
Predation | Hunting success | [
"Biology"
] | 3,384 | [
"Ecology"
] |
72,766,708 | https://en.wikipedia.org/wiki/32%20Virginis | 32 Virginis, also known as FM Virginis, is a star located about 250 light years from the Earth, in the constellation Virgo. Its apparent magnitude ranges from 5.20 to 5.28, making it faintly visible to the naked eye of an observer well away from city lights. 32 Virginis is a binary star, and the more massive component of the binary is a Delta Scuti variable star which oscillates with a dominant period of 103.51 minutes.
In 1914, Walter Sydney Adams announced that 32 Virginis is a spectroscopic binary. John Beattie Cannon published the first set of orbital elements for the binary system in 1915. Corrado Bartolini et al. made photometric observations of the star in early 1971, and found that the star showed variability due to pulsations. In 1974, 32 Virginis was given the variable star designation FM Virginis. Donald Kurtz et al. determined that the star was a Delta Scuti variable, in 1976.
The primary star is believed to be an Am star similar to rho Puppis - a pulsating post-main sequence star.
References
Delta Scuti variables
Virgo (constellation)
62267
110951
Durchmusterung objects
Virginis, FM
Virginis, 32
Virginis, d02 | 32 Virginis | [
"Astronomy"
] | 266 | [
"Virgo (constellation)",
"Constellations"
] |
72,767,014 | https://en.wikipedia.org/wiki/N%C3%ABna%20e%20Diellit | Nëna e Diellit ("the Mother of the Sun" or "the Sun's Mother") is a mother goddess in Albanian folk beliefs, the mother of Dielli ("the Sun"). A sacred ritual called "the funeral of the Sun's Mother" was very widespread in southeastern Albania until the 20th century. She has been described by scholars as a heaven goddess and a goddess of agriculture, livestock, and earth fertility, as suggested by the sacred ritual dedicated to her. Nëna e Diellit also features as a deity in Albanian folk tales. Nëna e Diellit represents a manifestation of the personification of the Sun in Albanian mythology.
Ritual
A sacred ritual called "funeral of the Sun's Mother" consisted in burying a female figure that probably personified a seasonal phase of the mother goddess. Occurring at the end of May, it was the last festival of the spring cycle, coinciding with the feast of Pentecost (Rusica). It was very widespread in southeastern Albania until the 20th century. During the custom the girls and young women gathered flowers, danced and sang, celebrating together with meals. After lunch or at the end of the day, they made a clay doll that they called Sun's Mother (Nëna e Diellit), put it on a tile and went outside the village to bury the female figure. It was performed in silence and with all the appropriate seriousness of the death ceremony. The girls and young women mourned the mother goddess, pronouncing the typical verses Nënë moj nënë, kuku / erdhi dielli e s'të gjeti "Mother oh Mother, Alas, / the Sun came and didn't find you".
Folk tales
Nëna e Diellit features as a deity in several Albanian folk tales. One of them has been collected by Albanologist Maximilian Lambertz and published under the title "Bei der Sonnenmutter" ["At the Sun's Mother"] in the collection Die geflügelte Schwester und die Dunklen der Erde: Albanische Volksmärchen [The Winged Sister and the Dark Ones of the Earth: Albanian Folk Tales]. Another has been collected by Albanologist Robert Elsie and published under the title "The Snake and the King's Daughter" in the collection Albanian Folktales and Legends.
See also
Zonja e Dheut
References
Citations
Bibliography
Albanian paganism
Albanian mythology
European goddesses
Agricultural goddesses
Fertility goddesses
Nature goddesses
Sky and weather deities | Nëna e Diellit | [
"Physics"
] | 526 | [
"Weather",
"Sky and weather deities",
"Physical phenomena"
] |
72,767,636 | https://en.wikipedia.org/wiki/Apafant | Apafant (WEB-2086, LSM-2613) is a drug which acts as a potent and selective inhibitor of the phospholipid mediator platelet-activating factor (PAF). It was developed by structural modification of the thienotriazolodiazepine sedative drug brotizolam and demonstrated that PAF inhibitory actions could be separated from activity at the benzodiazepine receptor. Apafant was investigated for several applications involving inflammatory responses such as asthma and conjunctivitis but was never adopted for medical use, however it continues to be used in pharmacology research.
References
Thienotriazolodiazepines
2-Chlorophenyl compounds
4-Morpholinyl compounds
Amides | Apafant | [
"Chemistry"
] | 164 | [
"Pharmacology",
"Functional groups",
"Medicinal chemistry stubs",
"Pharmacology stubs",
"Amides"
] |
72,768,126 | https://en.wikipedia.org/wiki/Buchwaldoboletus%20duckeanus | Buchwaldoboletus duckeanus is a species of bolete fungus in the family Boletaceae native to South America.
Taxonomy and naming
Originally described by Rolf Singer in 1983 as Pulveroboletus duckeanus, it was given its current name by Ernst Both and Beatriz Ortiz-Santana in A preliminary survey of the genus Buchwaldoboletus, published in "Bulletin of the Buffalo Society of Natural Sciences" in 2011.
Description
The cap is convex and viscid. Its color is brown. Easily peeled off the mushroom, the skin is separated from the flesh by a thin gelatinous layer. The pores are small and angular, and the pore surface stains blue with injury. The stipe is subferruginous and tapering, and there is a yellow bluing mycelium at the stipe base.
Spores are small and measure (4)5–6 by (3.3)3.5–4.2(4.5) μm.
Distribution and ecology
Buchwaldoboletus duckeanus has been recorded in Brazil, in Adolfo Ducke Forest Reserve. Like other Buchwaldoboletus species, it is not obligatorily ectomycorrhizal.
References
External links
Boletaceae
Fungi described in 1983
Fungi of South America
Fungus species | Buchwaldoboletus duckeanus | [
"Biology"
] | 275 | [
"Fungi",
"Fungus species"
] |
72,768,694 | https://en.wikipedia.org/wiki/Argopsin | Argopsin, also known as 1-chloropannarin, is a secondary metabolite produced by many lichen species, such as Biatora cuprea and Micarea lignaria.
Argopsin (also known as 1'-chloropannarin) is a chlorinated depsidone compound first isolated from the lichen Argopsis friesiana by Siegfried Huneck and Elke Mackenzie in 1975. It was independently discovered by both Huneck and Mackenzie's team and by Bodo and Molho in the same year. The structure was confirmed through multiple analytical methods including mass spectrometry, which showed characteristic isotope peaks at mass-to-charge ratios (m/z) of 396, 398, and 400 in a 9:6:1 ratio, indicating the presence of two chlorine atoms. Its UV spectrum matched that of pannarin, and infrared spectroscopy revealed characteristic aldehyde (1725 cm⁻¹) and hydroxyl (3500 cm⁻¹) bands. The researchers synthesized argopsin by chlorinating pannarin in acetic acid, which produced a compound identical to the naturally occurring substance. This synthesis also helped confirm a recently revised chemical structure of pannarin, correcting an earlier proposed structure from 1941.
In the lichen A. friesiana, argopsin occurs alongside atranorin, though its presence is described as "inconstant". The related species A. megalospora does not contain argopsin but instead contains various combinations of other lichen substances including atranorin, fumarprotocetraric acid, psoromic acid, and perlatolic acid.
The compound produces a red color when treated with ferric chloride in ethanol and an orange color with p-phenylenediamine in ethanol, characteristics useful for its identification.
Uses
Argopsin can have photohemolytic effect when activated under ultraviolet light with a wavelength of 366 nm.
Argopsin has been shown to have an in vitro effect on Leishmania at a concentration of 50 μg/ml.
References
Secondary metabolites
Lichen products
Chloroarenes
Heterocyclic compounds with 3 rings
Lactones
Cyclic ethers
Methoxy compounds
Benzodioxepines
Chlorine-containing natural products | Argopsin | [
"Chemistry"
] | 486 | [
"Chemical ecology",
"Natural products",
"Lichen products",
"Secondary metabolites",
"Metabolism"
] |
72,772,320 | https://en.wikipedia.org/wiki/Joggle%20%28architecture%29 | A joggle is a joint or projection that interlocks blocks (such as a lintel's stone blocks or an arch's voussoirs).
Often joggles are semicircular and knob-shaped, so joggled stones have a jigsaw- or zigzag-like pattern.
Joggling can be found in pre-Frankish buildings, in Roman Spain and Roman France.
In Islamic architecture, the earliest joggles were in the desert castles of the Umayyad Caliphate, such as Qasr al-Hayr al-Sharqi.
In Mamluk architecture, joggling is usually combined with ablaq (alternating colors).
Joggling also characterize Ottoman architecture in Cairo.
The protruding joggle is also called a "he-joggle", whereas the corresponding slot is called a "she-joggle".
See also
Dovetail joint: dovetailing can be considered a type of joggling.
References
Joinery
Masonry
Arabic architecture
Islamic architectural elements
Mamluk architecture
Ottoman architecture
Architecture in Egypt
Architecture in Syria
Architecture in the State of Palestine | Joggle (architecture) | [
"Engineering"
] | 230 | [
"Construction",
"Masonry"
] |
72,773,687 | https://en.wikipedia.org/wiki/Pehuensat-1 | Pehuensat-1 is a satellite built entirely in Argentina with educational objectives. It was launched on January 10, 2007 aboard a rocket from the Satish Dhawan Space Center on the east coast of India. The assembly took five years and was carried out by teachers and students of the National University of Comahue.
It was named Pehuensat-1 in reference to the pehuén, an ancient and native tree of the Andean Patagonian forests identified with the provinces in which the university has its academic headquarters.
Details
It was built by 17 teachers and 44 students from the Faculty of Engineering of the University of Comahue (Neuquén). In October 2006, the satellite was taken to the launch center in Shriharikota (India), by the Argentine space researcher Pablo de León, who became known months ago when he presented a prototype of a space suit designed for trips to Mars.
It was launched at 9:23 a.m. Indian time (1:53 a.m. Argentine time) on the Indian Polar Satellite Launch Vehicle PSLV C7 rocket.
After 20 minutes of travel, Pehuensat-1 reached its orbit, where it will remain -according to the technicians- for "several years".
The satellite weighs 6 kilograms, travels its orb LM Neuquen at an altitude of about 640 kilometers and orbits the Earth at a speed of (about . It has a space-type aluminum case structure and solar panels on one of the faces. The electronics are made up of a transmitter, a computer and two battery packs that are recharged with solar energy. In addition, an antenna in charge of transmitting the satellite parameters to the ground.
Pehuensat-1 can withstand temperatures in space of (every time it passes through the Earth's shadow) and up to (facing the Sun). It will be useful to high schools and universities around the world, because it transmits its data in multiple languages to amateur radio receivers. When flying over an area, The satellite only needs to tune to the 145.825 MHz frequency in the 2-meter band in FM mode. The Pehuensat-1 satellite transmits its data in Spanish, English and Hindi.
References
Satellites | Pehuensat-1 | [
"Astronomy"
] | 458 | [
"Satellites",
"Outer space"
] |
72,773,869 | https://en.wikipedia.org/wiki/Madhava%27s%20correction%20term | Madhava's correction term is a mathematical expression attributed to Madhava of Sangamagrama (c. 1340 – c. 1425), the founder of the Kerala school of astronomy and mathematics, that can be used to give a better approximation to the value of the mathematical constant (pi) than the partial sum approximation obtained by truncating the Madhava–Leibniz infinite series for . The Madhava–Leibniz infinite series for is
Taking the partial sum of the first terms we have the following approximation to :
Denoting the Madhava correction term by , we have the following better approximation to :
Three different expressions have been attributed to Madhava as possible values of , namely,
In the extant writings of the mathematicians of the Kerala school there are some indications regarding how the correction terms and have been obtained, but there are no indications on how the expression has been obtained. This has led to a lot of speculative work on how the formulas might have been derived.
Correction terms as given in Kerala texts
The expressions for and are given explicitly in the Yuktibhasha, a major treatise on mathematics and astronomy authored by the Indian astronomer Jyesthadeva of the Kerala school of mathematics around 1530, but that for appears there only as a step in the argument leading to the derivation of .
The Yuktidipika–Laghuvivrthi commentary of Tantrasangraha, a treatise written by Nilakantha Somayaji an astronomer/mathematician belonging to the Kerala school of astronomy and mathematics and completed in 1501, presents the second correction term in the following verses (Chapter 2: Verses 271–274):
English translation of the verses:
"To the diameter multiplied by 4 alternately add and subtract in order the diameter multiplied by 4 and divided separately by the odd numbers 3, 5, etc. That odd number at which this process ends, four times the diameter should be multiplied by the next even number, halved and [then] divided by one added to that [even] number squared. The result is to be added or subtracted according as the last term was subtracted or added. This gives the circumference more accurately than would be obtained by going on with that process."
In modern notations this can be stated as follows (where is the diameter of the circle):
Circumference
If we set , the last term in the right hand side of the above equation reduces to .
The same commentary also gives the correction term in the following verses (Chapter 2: Verses 295–296):
English translation of the verses:
"A subtler method, with another correction. [Retain] the first procedure involving division of four times the diameter by the odd numbers, 3, 5, etc. [But] then add or subtract it [four times the diameter] multiplied by one added to the next even number halved and squared, and divided by one added to four times the preceding multiplier [with this] multiplied by the even number halved."
In modern notations, this can be stated as follows:
where the "multiplier" If we set , the last term in the right hand side of the above equation reduces to .
Accuracy of the correction terms
Let
.
Then, writing , the errors have the following bounds:
Numerical values of the errors in the computation of
The errors in using these approximations in computing the value of are
The following table gives the values of these errors for a few selected values of .
Continued fraction expressions for the correction terms
It has been noted that the correction terms are the first three convergents of the following continued fraction expressions:
The function that renders the equation
exact can be expressed in the following form:
The first three convergents of this infinite continued fraction are precisely the correction terms of Madhava. Also, this function has the following property:
Speculative derivation by Hayashi et al.
In a paper published in 1990, a group of three Japanese researchers proposed an ingenious method by which Madhava might have obtained the three correction terms. Their proposal was based on two assumptions: Madhava used as the value of and he used the Euclidean algorithm for division.
Writing
and taking compute the values express them as a fraction with 1 as numerator, and finally ignore the fractional parts in the denominator to obtain approximations:
This suggests the following first approximation to which is the correction term talked about earlier.
The fractions that were ignored can then be expressed with 1 as numerator, with the fractional parts in the denominators ignored to obtain the next approximation. Two such steps are:
This yields the next two approximations to exactly the same as the correction terms
and
attributed to Madhava.
See also
Madhava series
Madhava's sine table
References
Additional reading
Pi
History of calculus
Kerala school of astronomy and mathematics
Mathematical series | Madhava's correction term | [
"Mathematics"
] | 997 | [
"Sequences and series",
"Mathematical structures",
"Series (mathematics)",
"Calculus",
"Mathematics of infinitesimals",
"Pi",
"History of calculus"
] |
72,774,355 | https://en.wikipedia.org/wiki/9%20Cassiopeiae | 9 Cassiopeiae (9 Cas) is a white giant star in the constellation Cassiopeia, about 2,370 light years away.
9 Cassiopeiae is classified as an A1 type giant or bright giant. One study noted peculiarities in the spectrum that could indicate a λ Boötis star, but other researchers have refuted this.
At an age of 25 million years, 9 Cassiopeiae has expanded away from the main sequence after exhausting its core hydrogen and now has a radius about 26 times that of the Sun. With an effective temperature of about , it emits more than two thousand times the luminosity of the Sun.
9 Cassiopeiae has a number of faint companions listed in multiple star catalogues, but they all appear to be at different distances and none are thought to be gravitationally associated.
References
A-type bright giants
Cassiopeia (constellation)
Cassiopeiae, 09
9100
225180
000330
BD+61 2586
Lambda Boötis stars | 9 Cassiopeiae | [
"Astronomy"
] | 209 | [
"Cassiopeia (constellation)",
"Constellations"
] |
72,774,533 | https://en.wikipedia.org/wiki/Czech%20Mathematical%20Society | The Czech Mathematical Society (, CMS) is an association of researchers, teachers, professionals and other persons interested in mathematics. Formally, the CMS is one of the four sections (subsidiary associations) of the Union of Czech Mathematicians and Physicists (JČMF). Membership in the CMS is therefore conditional on membership in JČMF.
It was founded in 1972 originally under the name Mathematical Research Section. In 2004 it was renamed to its current name.
The CMS is managed by a twelve-member Executive Committee, which is elected by the members of the society. The Executive Committee elects the President of the CMS from among its members. The current President (2022–2026) is Luboš Pick.
The CMS is a member of the European Mathematical Society and associate member of the International Council for Industrial and Applied Mathematics (ICIAM).
The Union of Czech Mathematicians and Physicists is the Adhering Organization through which the Czech Republic adheres to the International Mathematical Union (IMU). The Czech Republic's membership in the IMU is represented by the Czech Committee for Mathematics.
Activities
The Czech Mathematical Society organizes a number of activities, in particular:
Organizing an annual competition for university students in scientific activity in mathematics and informatics, in cooperation with the Slovak Mathematical Society.
Supporting a number of events for pupils and high-school students with the aim of popularizing mathematics and improving mathematics education.
Organizing the quadrennial Conference of Czech Mathematicians and participating together with other organizations and institutions in organizing other scientific events.
Organizing public lectures popularizing mathematics.
Awarding the Honorary Medal for Mathematics to Czech and Slovak specialists for their important contributions to development of the fields of mathematics and didactics of mathematics in the Czech Republic, and to eminent foreign specialists in the fields of mathematics and didactics of mathematics who have had long-term collaboration with institutions in the Czech Republic.
Awarding the Czech Mathematical Society Prize for Young Researchers.
References
External links
About Czech Mathematical Society (CMS)
The Union of Czech Mathematicians and Physicists
Mathematical societies
Organizations established in 1972
Mathematics awards
Organizations based in Prague
Scientific societies based in the Czech Republic | Czech Mathematical Society | [
"Technology"
] | 429 | [
"Science and technology awards",
"Mathematics awards"
] |
72,775,895 | https://en.wikipedia.org/wiki/79%20Tauri | 79 Tauri, also known as b Tauri, is an Am star in the constellation of Taurus with an apparent magnitude of 5.0. It is a member of the Hyades open cluster and parallax measurements by Gaia give a distance of about .
The spectrum of 79 Tauri shows abnormal abundances of metals, with many showing unusually strong absorption lines, but some such as calcium showing weaker lines than expected. This is represented in the spectral type kA5hF0VmF0, which is F0 based on its hydrogen lines, but A5 based on its calcium K-lines, and F0 based on the lines of other metals. Other publications often give the spectral class based on hydrogen lines as A7. It is classified as an Am star, a type of star with strong magnetic fields and slow rotation causing stratification of elements within its atmosphere.
79 Tauri lies about two degrees south of the main V asterism of the Hyades open cluster. It lies 11 light years from the centre of the cluster and is generally considered to be a member. With a mass of , it is a main sequence star with an age of 971 million years. It has an effective temperature of and a radius of , it radiates 18 times the luminosity of the Sun.
References
Taurus (constellation)
Tauri, b
Tauri, 079
A-type main-sequence stars
Durchmusterung objects
028355
1414
020901 | 79 Tauri | [
"Astronomy"
] | 308 | [
"Taurus (constellation)",
"Constellations"
] |
72,776,413 | https://en.wikipedia.org/wiki/CAMM%20%28memory%20module%29 | Compression Attached Memory Module (CAMM) is a memory module form factor which uses a land grid array, and developed at Dell by engineer Tom Schnell as a replacement for DIMMs and SO-DIMMs which use edge connectors and had been in use for about 25 years. The first SO-DIMMs were introduced by JEDEC in 1997.
CAMM was created to overcome technical limitations of traditional slotted DIMM. The CAMM module allows for shorter traces on the motherboard PCB as compared to SO-DIMM, allowing the memory to be run with less power and at higher speeds. The memory module is pressed and held in place against a bar with land grid array pin contacts which connect to the motherboard.
Advantages of CAMM include lower thickness, allows for replaceable LPDDR modules, faster speeds above 6400MT/s, higher capacities up to 128GB per module and higher memory bandwidth. Disadvantages are that it cannot be mounted without tools and uses screws. Systems with CAMM memory already installed cannot be expanded through adding additional CAMM modules in the same way that 2 DIMMs can be added alongside 2 existing DIMMs to expand total system memory. Instead, the entire CAMM module must be replaced with one with a higher capacity. So CAMM may be of benefit for laptops and ITX systems.
The total number of interface contact points of CAMM is 616 (44 per row times 14 rows).
History
In April 2022, Dell launched laptops in the Dell Precision 7000-series that used a custom form factor of CAMM for DDR5 SDRAM.
In June 2023, ADATA demoed an updated design CAMM memory module, which looks different (and more compact) than Dell's 2022 design.
The Compression Attached Memory Module specification was finalised and published by JEDEC as CAMM2 on December 5, 2023.
The first computer, and laptop, to use CAMM2 memory modules is the Lenovo ThinkPad P1 Gen 7 released in April 2024.
In May 2024, MSI announced the first desktop consumer motherboard with CAMM2 support, the Z790 Project Zero Plus.
References
External links
JESD318, Compression Attached Memory Module (CAMM2) Common Standard (Ver. 1.02 Nov 2023)
Computer memory form factor
Computer-related introductions in 2022
Dell | CAMM (memory module) | [
"Technology"
] | 487 | [
"Computing stubs"
] |
72,777,352 | https://en.wikipedia.org/wiki/HD%2025558 | HD 25558, also known as V1133 Tauri and by its Flamsteed designation 40 Tauri, is a star located about 700 light years from the Earth, in the constellation Taurus. Its apparent magnitude is about 5.3, making it faintly visible to the naked eye of an observer far from city lights. It is a variable star, ranging in brightness from Hipparcos magnitude 5.28 to 5.32 over a period of 1.53232423 days.
In 1998, HD 25558 was discovered to be a variable star by Christoffel Waelkens et al. who analyzed the Hipparcos photometric data for hundreds of stars, and classified HD 25558 as a slowly pulsating B star with a period of 1.53 days.
Beginning in 2008, HD 25558 was the subject of an observing campaign by Ádám Sódor et al. who gathered data collected from 17 observatories on the ground and in space. This star was chosen for the project because it is relatively bright, located near the celestial equator (and thus observable from almost anywhere on Earth), and the slow rotation indicated in earlier studies would simplify the interpretation of spectra. The investigators concluded that HD 25558 is a spectroscopic binary with a period of about 8.9 years, but not enough data was available to derive a full description of the orbit. Both components of the binary show detectable stellar pulsations. The primary star rotates with a period of about 6 days, and the secondary rotates in just 1.2 days. The primary has no detectable magnetic field, but the secondary's field strength is at least a few hundred gauss. The dominant 1.53 day pulsation period arises from the primary star and those pulsations were coherent over the 20 year period spanned by the data used in the study.
Notes
References
Slowly pulsating B-type stars
Taurus (constellation)
18957
25558
Durchmusterung objects
Tauri, V1133
Tauri, 40
B-type main-sequence stars | HD 25558 | [
"Astronomy"
] | 426 | [
"Taurus (constellation)",
"Constellations"
] |
72,777,484 | https://en.wikipedia.org/wiki/Bohr%20Festival | The Bohr Festival () was a series of seven lectures given by Niels Bohr 12 to 22 June 1922 at the Institute of Theoretical Physics in Göttingen. These were the Wolfskehl Lectures, funded by the Wolfskehl Foundation. Taking place in the fortnight leading up to the Göttingen International Handel Festival, it became known as the Bohr Festival. In 1991, Friedrich Hund suggested that James Franck responsible for the comparison.
In the lectures Bohr outlined the current development of the Bohr-Sommerfeld theory, remarking "how incomplete and uncertain everything still is".
References
1920 in Germany
Quantum mechanics | Bohr Festival | [
"Physics"
] | 127 | [
"Quantum mechanics",
"Quantum physics stubs",
"Works about quantum mechanics"
] |
72,777,538 | https://en.wikipedia.org/wiki/Tetrapropyltin | Tetrapropyltin is an organotin compound with the formula . It is a toxic colorless oily liquid. It reacts with strong oxidizing agents. This chemical irritates the skin, eyes and respiratory system. It is very toxic to aquatic life with long-lasting effects. It can be absorbed through the skin, causing toxic effects on the body. Tetrapropyltin is an intermediate in the synthesis of dipropyltin dichloride.
References
Organotin compounds | Tetrapropyltin | [
"Chemistry"
] | 105 | [
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
78,554,851 | https://en.wikipedia.org/wiki/C/1864%20O1%20%28Donati%E2%80%93Toussaint%29 | Comet Donati–Toussaint, formally designated as C/1864 O1, is a non-periodic comet co-discovered by Italian astronomers, Giovanni Battista Donati and Carlo Toussaint in July 1864.
Discovery and observations
On the night of 23 July 1864, astronomers Giovanni Battista Donati and Carlo Toussaint spotted a new comet within the constellation Coma Berenices. Their discovery was confirmed four days later on July 27. Although it never came close to either the Sun or the Earth to allow itself to become a bright object, astronomers were able to observe it until 25 February 1865, and thus were able to determine its orbit with higher precision.
References
Notes
Citations
External links
Non-periodic comets | C/1864 O1 (Donati–Toussaint) | [
"Astronomy"
] | 142 | [
"Astronomy stubs",
"Comet stubs"
] |
78,555,747 | https://en.wikipedia.org/wiki/C/1864%20R1%20%28Donati%29 | Comet Donati, formally designated as C/1864 R1, is a parabolic comet discovered in 1864. It was the last of five comets discovered by Italian astronomer, Giovanni Battista Donati. This comet might be the potential parent body of the Gamma Normids meteor shower (alongside C/1893 U1).
Discovery and observations
The comet was already on its outbound flight when it was first spotted by Giovanni Battista Donati on the night of 10 September 1864, where it was initially located within the constellation Leo Minor. As a result, further observations of the comet became increasingly difficult as it slowly faded away, leading to astronomers being unable to obtain its precise orbital elements. The last known observation of the comet was recorded on 20 October 1864.
References
Notes
Citations
External links
Non-periodic comets
Hyperbolic comets
Near-Earth comets
Meteor shower progenitors | C/1864 R1 (Donati) | [
"Astronomy"
] | 171 | [
"Astronomy stubs",
"Comet stubs"
] |
78,555,863 | https://en.wikipedia.org/wiki/Lichenoconium%20edgewoodense | Lichenoconium edgewoodense is a species of lichenicolous (lichen-dwelling) fungus in the family Lichenoconiaceae. This parasitic fungus was described as a new species in 1998 by Vagn Alstrup and Mariette S. Cole. The species epithet, originally published with the spelling edgewoodensis, was later corrected to edgewoodense. The host of the fungus is the common and widespread foliose lichen species Parmelia sulcata. Lichenoconium edgewoodense has been recorded from British Columbia (Canada) and South Greenland.
Description
Lichenoconium edgewoodense is a lichenicolous fungus, meaning it grows on and may derive nutrients from lichens. Early in its life cycle, it behaves as a parasite, potentially transitioning to a saprophytic (feeding on dead or decaying material) lifestyle as it matures. The fungal reproductive structures, known as pycnidia, are small and often partially embedded in the host lichen's surface. They measure up to about 0.15 mm in diameter. Initially, these pycnidia remain hidden beneath the lichen's (its outer layer), appearing as dispersed greyish spots on a visibly unhealthy lichen thallus. As they mature, the pycnidia develop broad, black openings (ostioles) through which spores are released.
The cells that produce the spores (conidiogenous cells) are roughly 6–8 micrometres (μm) long and about 2 μm wide. The spores themselves (conidia) are oblong, slightly constricted in the middle, and measure about 5–6 by 3.0–3.5 μm. These conidia are thicker-walled than those of many related species and have smooth surfaces. The distinctive shape of the conidia sets Lichenoconium edgewoodense apart from other members of Lichenoconium, which typically have rounder or differently constricted spores.
Habitat and distribution
This fungus was originally described from specimens collected from the type locality in British Columbia's interior cedar-hemlock forest zone, at an elevation of roughly 700 metres. It is found on Parmelia sulcata, a common foliose lichen species. Its known range was extended greatly when it was recorded from South Greenland in 2009.
References
Dothideomycetes
Fungus species
Lichenicolous fungi
Fungi described in 1998 | Lichenoconium edgewoodense | [
"Biology"
] | 505 | [
"Fungi",
"Fungus species"
] |
78,556,095 | https://en.wikipedia.org/wiki/Nephrocalcin | Nephrocalcin is an acidic glycoprotein, is produced by renal proximal tubule cells. It inhibits crystal nucleation, growth and aggregation. It is one of the key inhibitors for Nephrolithiasis, kidney stone disease.
There are at least 4 known isoforms of Nephrocalcin: NC-A, NC-B, NC-C, and NC-D. A higher secretion of NC-C and NC-D is found in kidney stone patients, whereas a higher secretion of NC-A and NC-B in non-patients.
References
Glycoproteins | Nephrocalcin | [
"Chemistry"
] | 134 | [
"Glycoproteins",
"Glycobiology"
] |
78,557,411 | https://en.wikipedia.org/wiki/Jenolite | Jenolite is a British company based in Bedfordshire, England that develops and sells rust treatment products.
History and operations
Jenolite, founded in 1939 by John H. Lawrence, initially specialized in rust inhibitors and converters before expanding to include primers and other metal treatment products. During and after World War II, it supplied anti-corrosion products for reconditioning military vehicles, supporting both the Ministry of Supply and Ministry of Defence. By the 1950s, Jenolite had expanded abroad with manufacturing sites in the US, Australia, and Belgium, where it contributed to NATO’s equipment reconditioning efforts. In the 1960s, Jenolite was integrated into Duckham Oils Ltd., and its products became widely used for industrial corrosion protection and restoration projects, such as the SS Great Britain.
Ownership changes occurred in the 1980s, eventually leading to acquisitions by Permalite and later Armour Trust, and by 2000, the brand was under Pennzoil-Quaker State with limited attention. A new Jenolite company was established in 2013, revitalizing the brand with an e-commerce business model and expanded operations in the UK, focusing on products for industrial, automotive, and restoration applications.
References
Chemical companies of England
Corrosion prevention
Companies based in Bedfordshire
Biggleswade
British companies established in 1939 | Jenolite | [
"Chemistry"
] | 263 | [
"Corrosion prevention",
"Corrosion"
] |
78,559,522 | https://en.wikipedia.org/wiki/The%20World%20in%20the%20Model%3A%20How%20Economists%20Work%20and%20Think | The World in the Model: How Economists Work and Think is a work by Mary S. Morgan published by Cambridge University Press in 2012.
Content
Mary S. Morgan, defined by Robert Sugden "a major philosopher and historian of economics", analyzes with examples how economists work and think using models. Her book reconstructs the path taken by models to become economists' "natural way of doing economics."
For Morgan, both the "method of mathematical postulation and proof" and that of modelling have emerged in late 19th century, and models have become economists' main tools only from the 1930s, replacing classical economics relying on "universal laws".
A concept stressed throughout this work is that:
The pragmatic orientation of her work is stated right at the beginning, noting that "Science is messy", thus
According to Morgan, who draws a parallel with physics, economists follow four general steps in their work with models:
Step 1: Create a model the is relevant to the problem at hand
Step 2: Interrogate the model
Step 3: Demonstrate the answer to a question using the internal resources and dynamics of the model
Step 4: Build a narrative that links the answers offered by the model to the external world
For the Author, economists
The existence of a world inside the model itself is a central feature of the work. Modelling is not just an activity of abstraction, simplification, idealization, and mathematization, but entails the creation of new artifacts to be explored and reasoned with, in a play where the economist and the model are "jointly active participants".
As noted by Sugden, Morgan repeats at several point this double function of models:
The case studies span a period going from early nineteenth century to the second half of the twentieth century, though the earlier Quesnay's Tableau économiques are mentioned among the antecedents of modelling (Chapter 1). Models start thus with Ricardo's "model farm" (Chapter 2), to study for example how an increase in grain prices would affect rents, to continue with the Edgeworth box for the trading of goods, later the subject of developments by Vilfredo Pareto (Chapter 3), with the rational agent (Chapter 4), and with Newlyn–Phillips hydraulic machine of the economy (Chapter 5). The book continues with the business cycle work of Ragnar Frisch and Jan Tinbergen (this latter father of Econometrics), and the macroeconomic models of Meade, Samuelson and Hicks (Chapter 6), with supply and demand models (Chapter 7), all the way to modern simulation modelling (Chapter 8). Monte Carlo methods are included, and a full chapter (Chapter 9) is devoted to the Prisoner Dilemma, where the Author discusses Nash equilibrium using both the classical example of the two prisoners confronted with the choice to either confess or stay silent while ignoring their companion's choice, and a less seen example drawn from Puccini's Tosca, with illustrations from a paper of Anatol Rapoport.
As noted by economist Gene Callahan Morgan is attentive to the specialized talents that are needed in economic modelling, including a tacit, craft-based, knowledge that can only be acquired via apprenticeship.
In discussing what makes a model "fruitful" Morgan notes that while they must have enough internal resources to operate, including some salient aspects of "the economic world," they need to be able to generate variety in their outcome, as to potentially surprise the analyst, even when the surprise is that too many solutions are possible, as noted by Paul Samuelson when trying to translate Keynes's General Theory of Employment, Interest and Money into a model. Also, size in relation to content matters, so that models must also be small enough to be manipulable.
Morgan aims to provide an account of "modelling (in economics) as an autonomous epistemic genre". In this, the use of narratives in relation to models is not just rhetorical; it is foremost epistemological. Ragnar Frisch's image of the business cycle as a rocking horse randomly hit by a boy with a club successfully conveyed to the economist of the 1930's the concept of an harmonic process impulsed by shocks. The centrality of narration for models in the work of Morgan is noted by François Claveau and Gene Callahan. This latter notes how this is well illustrated by the prisoner dilemma, that would be incomprehensible if offered only in terms of payoffs, without the accompanying story.
Chapter 7 offers a discussion of what makes models different from physical experiments. Morgan sees a difference in that experiments are "made of the same stuff" of the world, while in the case of models "there is no shared stuff".
Coming to how economic models influence policy thanks to their scientific authority, Morgan, citing Nancy Cartwright, offers a word of caution:
Reception
The book is praised by Verena Halsmayer and by Maxime Desmarais-Tremblay for showing the variety of tools mobilized by economists, such as the hydraulic system of the Newlyn–Philips Machine made of pipes, valves and tanks, graphs such as those of the Edgeworth box, pen and paper tabulated records such as Ricardo's ideal farm, conceptual games such as the Prisoner dilemma, and modern day equations.
For François Claveau it is disappointing that Morgan, though author of The History of Econometric Ideas (1990) does not discuss econometric models, nor the distinction between these, embedded into real world data and statistical testing, and non-econometric models. Claveau also laments the absence of a discussion of the difference between theories and models.
A limit of Morgan's work that is flagged by Verena Halsmayer is that in examining a selected set of successful models the book discounts alternative traditions, the "verbal economics" and other historical traditions, evading the strategic development leading to the dominance of (neoclassical) economic modeling, thus ignoring "what was lost by adopting modeling as the dominant mode of economic knowledge production".
Robert Sugden praises Morgan's vivid portrait of Ricardo. Morgan details how the numerical examples of his model farm were inspired by agricultural experiments run by other gentleman farmers. The same reviewer notes that the book of Morgan, as the tile implies, has more to say about how economist work inside the model than in how they look at the world outside it. As a modeller, Sugden suggests that Morgan's emphasis on how economists manipulate their models to obtain insights may discount models' autonomy, and in what way models may speak with their own voice.
For this work Morgan won in 2013 the best book award from The European Society for the History of Economic Thought.
See also
Sociology of quantification
Models as Mediators
References
Economics books
2012 non-fiction books
Philosophy of science
History of probability and statistics
Science and technology studies | The World in the Model: How Economists Work and Think | [
"Mathematics",
"Technology"
] | 1,406 | [
"Probability and statistics",
"Science and technology studies",
"History of probability and statistics"
] |
78,559,896 | https://en.wikipedia.org/wiki/NGC%201157 | NGC 1157 is a spiral galaxy located in the constellation Eridanus. It has been classified as an "Sb" type spiral galaxy. The galaxy's redshift (z) of 0.029544 places it at a distance of about 124.8 megaparsecs (407 million light-years) from Earth. NGC 1157 has angular dimensions of 0.60' by 0.3' and is faint, with a visual magnitude of 14.8 and a blue magnitude of 15.6. Its surface brightness is about 12.8 magnitudes per square arcminute. NGC 1157 is also cataloged as PGC 11218.
Discovery and observation
NGC 1157 was first observed by astronomer William Herschel on November 26, 1785. It has since been cataloged in the New General Catalogue (NGC) and is part of a small group of galaxies in the region, including NGC 1155, NGC 1156, NGC 1158, and NGC 1159.
Nearby galaxies
NGC 1157 is located near other galaxies such as NGC 1155, NGC 1156, and NGC 1158. These galaxies are part of the Eridanus constellation and contribute to the galaxy groupings in this region of the sky.
References
External links
Go Astronomy - NGC 1157 Overview
1‡NGC 1157 - spiral galaxy
Spiral galaxies
NGC objects
Eridanus (constellation) | NGC 1157 | [
"Astronomy"
] | 279 | [
"Eridanus (constellation)",
"Constellations"
] |
78,560,571 | https://en.wikipedia.org/wiki/Organocalcium%20chemistry | Organocalcium chemistry is the chemistry of compounds containing a calcium to carbon bond, or in broader definitions, organic compounds that contain calcium. Although discovered around the same time as the now commonly utilized organomagnesium compounds, organocalcium compounds were subject to greatly reduced interest due to drastic differences in stability. However, recent advances in stabilization of these highly reactive compounds has spurred increased interest in organocalcium compounds and allowed for multiple research directions to form. Because calcium metal is less reactive to organic reagents than magnesium and the organocalcium compounds are more reactive than organomagnesium compounds, synthesis of novel compounds still poses a significant challenge. Calcium also has access to empty d orbitals that the lighter alkaline earth metals cannot access, and the degree to which this affects bonding and reactivity has sparked a fundamental debate. Lastly, despite the inherent instability of most organocalcium complexes, the unique basicity and size of the calcium ion together with the highly polarized bonds formed has opened up applications for organocalcium compounds in organic transformations and catalytic cycles.
Compounds
In general, organocalcium synthesis is complicated by relatively unreactive calcium metal (compared to magnesium or the alkali metals due to a high atomization energy) and high reactivity of most organocalcium compounds to oxygen, water, and even ethereal solvents. To sustain the highly electropositive calcium center, the vast majority of compounds have anionic ligands by which they can be categorized, with neutral coordinating ligands utilized for increased stability.
Aryl, allyl, and alkyl derivatives
The earliest organocalcium compounds to receive some sustained interest were alkyl- and arylcalcium compounds. The first of these was reported in 1905 by Ernst Beckmann, where synthesis of phenylcalcium iodide was claimed following stirring of calcium shavings with iodobenzene in diethyl ether (Et2O). Subsequent study by Henry Gilman and Ferdinand Schulze argued that the isolated product in this report was actually the Et2O adduct of CaI2, and, although phenylcalcium halides have been reported numerous times, they are usually characterized through subsequent derivatization products. It took a full century until, in 2005, Matthias Westerhausen and colleagues obtained the first structural characterization of an arylcalcium compound, crystallizing phenylcalcium iodide as an adduct of tetrahydrofuran (THF) and calcium oxide. A consistent challenge in the formation of organocalcium compounds has been the activation of calcium metal. Recent advancements in mechanochemistry have opened up simpler synthetic setups, with unactivated calcium being used to form arylcalcium reagents in situ during ball-milling.
Allylcalcium compounds have also seen recent synthetic success, beginning with Timothy Hanusa and colleagues’ synthesis of a bis(allyl)calcium complex stabilized by sterically large, silyl substituents. These successes have largely been driven by the use of salt metathesis reactions, where potassium salts of allyl anions exchange metals with a calcium halide, typically CaI2. This same strategy has been used to synthesize the unsubstituted complex Ca(η3-C3H5)2 as a soluble triglyme adduct. This has been proven to be a versatile strategy, with a full series of substituted allylcalcium complexes of different sizes also characterized through a salt metathesis pathway.
The carbon atom in the calcium-carbon bond takes on a significant negative charge. Because of the greater nucleophilicity of alkyl ligands, the alkylcalcium reagents are in general harder to synthesize than the arylcalcium compounds. A common stabilizing strategy is to use bulky silyl and phenyl substituents to stabilize this negative charge. When targeting a Grignard analogue, the decreased reactivity from this method and the poor stability of the less protected methyl- and ethylcalcium halides has led to in situ generation of reactive alkylcalcium halides as the preferred method over the synthesis of isolable compounds. Because of this poor stability, the pure organometallic dimethylcalcium was only isolated in 2018 by Reiner Anwander and colleagues as an insoluble, amorphous solid, with the THF adduct being structurally characterizable as a heptametallic cluster.
Metallocenes
Few calcium metallocenes (“calcocenes”) have been isolated, but they are of particular interest due to the insights into bonding that have come from their study. The first synthesis of Cp2Ca (Cp = cyclopentadienyl) from calcium metal and cyclopentadiene in THF produced an insoluble, polymeric product. A crystal structure showed that, unlike most transition metal metallocenes, the Cp-Ca-Cp angle is significantly bent and Cp2Ca has an opening that can be utilized to access derivatives. As seen in the first monomeric synthesis of a calcocene, ethereal solvents such as Et2O and THF almost always coordinate in this opening and can be challenging to remove through sublimation. This bent structure can be leveraged into different coordination environments. For example, two butenyl-substituted Cp ligand will coordinate to Ca through both the five-membered rings and the olefins, but the olefins will not coordinate to Mg, where the Cp-Mg-Cp angle is not bent.
Low-oxidation-state compounds
Although low oxidation state beryllium and magnesium chemistry has developed significantly in the last two decades, only a few reports exist of organocalcium compounds stabilizing any oxidation state other than Ca(II). The first and only report of an isolable Ca(I) compound came in 2009, where two THF-coordinated Ca(I) ions sit on either side of an arene ring. The π-antibonding orbitals of the sandwiched arene help stabilize the two calcium ions, which are further stabilized by the coordinating solvent. Other studies of Ca(I) were done at low temperatures in exotic conditions or examine formally Ca(II) compounds that imply Ca(I)-containing intermediates either during synthesis or further reactivity. A landmark example of this from Sjoerd Harder and coworkers is the reported reduction of arenes and N2 by a bridged Ca(I)-Ca(I) species generated in situ. The ease of activating the normally inert N2 to turn it into a strong reductant even at room temperature highlights the instability of Ca(I) species. Although not isolable as a Ca(I)-Ca(I) dimer, it possesses similar reactivity as a stronger reducing agent than a Mg(I) dimer.
Amides, hydrides, and fluorides
There are several classes of calcium complexes that have become especially relevant despite not necessarily containing a Ca-C bond. The calcium amides, for example, have been investigated for numerous applications as a stoichiometric or catalytic reagent. Several modern synthetic strategies have allowed for a wide range of calcium amides to realized. Transmetalation, such as from a Sn(II) amide, allowed for the early preparation of amides yet again stabilized by bulky silyl groups. Additional electronic and kinetic stabilization can be provided through carbenes, despite lacking the π-backbonding that other main group elements are capable of. A breakthrough in eliminating side product formation and other contamination was the development of mechanochemical syntheses that forgo the use of solvent. Simply ball-milling CaI2 with a potassium amide salt yielded the corresponding bis(amido) complex.
Inspired by the well-studied and useful solid-state CaH2, several molecular calcium hydrides have been synthesized with the hope of interesting small molecule activation. In 2006, Sjoerd Harder and Julie Brettar accomplished the synthesis of a well-defined, dimeric calcium hydride through the reaction of a calcium amide with phenylsilane. Subsequent studies have expanded the library of stabilizing ligands, but all are multidentate ligands that coordinate through nitrogen sites.
Several recent advances have been made in the synthesis of molecular calcium fluorides. The solid-state CaF2 is an important source of fluorides for organofluorine compounds, but rely on dangerous HF intermediates. The early well-characterized molecular calcium fluorides are clusters and are formed by reacting CaF2 with large, multidentate ligands. Recent work from Simon Aldridge and coworkers have resulted in more accessible fluoride coordination environments that can act as reagents for nucleophilic fluoride addition to organic compounds.
Bonding Descriptions
The changes in properties going down the alkaline earth group causes calcium to possess qualitatively entirely distinct bonding characteristics than the lighter beryllium and magnesium ions. In particular, calcium is significantly larger, more reducing, and has a much lower electronegativity. This enforces a strong preference for the Ca(II) oxidation state and an essentially ionic bond with carbon, which can be reasonably described as a carbanion in the Ca-C bond.
A key difference in calcium bonding descriptions compared to magnesium and beryllium is the occasional use of the unfilled 3d orbitals to fully explain bonding and structural patterns. For example, the bent nature of calcocene, and the potentially bent geometry of CaH2, can be explained by increased involvement of the 3d orbitals in bonding. This has been highly debated, however, with other explanations invoking the polarizability of the larger Ca core and a stabilizing van der Waals interaction between the two ligands. A similar debate is ongoing regarding the degree of π-backbonding in a Ca(CO)8 complex. Although still controversial, computational studies on the degree of sp-d hybridization have caused some to label Ca as an honorary transition metal.
Reactivity
Heavy Grignard reactivity
Organocalcium compounds show some more similarities to organolithium chemistry over organomagnesium compounds. This is largely due to differences in electronegativity, which allow organocalcium compounds to function as a base more often than typical magnesium-based Grignard reagents do. This basicity is exemplified by the facile deprotonation and subsequent cleavage of ethers such as THF.
Another point of differentiation from the magnesium-based Grignard reagents is the higher positive charge localized on the calcium atom, due to the higher degree of ionicity in the Ca-C bond versus the Mg-C bond, which can enable unique reactivity not seen in the lighter alkaline earth compounds. For example, a dimeric Ca alkynide complex was shown to enable the coupling of two anionic alkynides to form an extended, fully double bonded four-carbon chain. The previously mentioned in situ generation of reactive alkylcalcium species has also been successfully used to react with amines to form calcium amides. This reactivity relies on fast ligand exchange of calcium Grignard reagents due to the ionic nature of this bond – the initially formed product is a heteroleptic calcium monoamide monohalide, but ligand exchange quickly forms the full calcium diamide and an insoluble calcium dihalide that drives the Schlenk equilibrium to completion. Non-Grignard alkylcalcium complexes have also shown unique reactivity, such as alkylation of benzene driven by the formation of a calcium hydride.
Catalytic reactivity
Catalysis with organocalcium compounds has historically been limited due to poor stability. However, significant recent progress has been made in multiple areas of catalytic applications. Inspired by alkali metal-based organometallic compounds use in anionic polymerization, organocalcium compounds have also been investigated as polymerization catalysts. For example, fast polymerization has been seen for polylactide synthesis with excellent selectivity for the isotactic form. This is not only enabled by the previously discussed electronic and electrostatic differences, but also by the larger size of calcium in comparison to the alkali metals or magnesium. The larger size of calcium allows an unusual trigonal prismatic coordination geometry utilized throughout the mechanism. The ionic nature of Ca-C bonding can also be leveraged for living polymerization, as was demonstrated for a stereoselective synthesis of polystyrene.
Catalysis has also been performed using organocalcium compounds for a series of organic transformations. This most prominently includes hydroamination, where numerous viable substrates and modes of selectivity have been demonstrated. Catalytic activity has also been shown for the analogous hydrophosphination, the hydrogenation of alkene with dihydrogen, regioselective hydrosilylation of conjugated alkenes, and the hydroboration of alkenes, although the role of calcium in the latter mechanism is still debated. The redistribution of arylsilane and hydrosilane groups has also been performed catalytically, relying on the cleavage and reformation of C-Si and Si-H bonds driven by the simultaneous cleavage and reformation of Ca-C and Ca-H bonds.
References
Calcium
Organometallic chemistry | Organocalcium chemistry | [
"Chemistry"
] | 2,815 | [
"Organometallic chemistry"
] |
78,560,687 | https://en.wikipedia.org/wiki/NGC%201158 | NGC 1158 is a lenticular galaxy located in the constellation Eridanus. It was discovered by the American astronomer Francis Leavenworth on January 2, 1886. The galaxy lies approximately 133 million light-years away from Earth and has an apparent magnitude of 13.1 in the visual band.
NGC 1158 has a redshift of 0.009870, indicating that it is receding from Earth at a velocity of about 2960 km/s.
References
Lenticular galaxies
Eridanus (constellation)
1158 | NGC 1158 | [
"Astronomy"
] | 108 | [
"Eridanus (constellation)",
"Constellations"
] |
78,560,779 | https://en.wikipedia.org/wiki/Luigi%20Mangione | Luigi Nicholas Mangione ( ; born May 6, 1998) is an American man who was identified as the suspect in the killing of Brian Thompson, the CEO of UnitedHealthcare, which occurred in December 2024.
Amidst a nationwide manhunt, Mangione was arrested and arraigned in Altoona, Pennsylvania, five days after the shooting. After waiving extradition in Pennsylvania, he appeared in a federal court in New York City. Mangione was arraigned in the New York Supreme Court and pleaded not guilty to his state charges. Mangione has been indicted on eleven state charges and faces four federal charges. These include first-degree murder, murder in furtherance of terrorism, criminal possession of a weapon, and stalking. The federal murder by firearm charge makes him eligible for the death penalty, although federal prosecutors have yet to indicate whether they will pursue it.
Since his arrest, Mangione has received support online, with some celebrating him as a folk hero. Opinion polls found that a majority of American adult respondents held a negative view toward Mangione, with younger and left-leaning respondents more likely to support him. The support Mangione has generated has been connected to negative views of the health insurance industry and harmful claim denial practices. The case has spurred growing calls for health insurance reform.
Early life, education, and career
Mangione was born in Towson, Maryland, on May 6, 1998 to a Baltimore-area family of Italian descent. His paternal grandfather, Nicholas Mangione, was born to poor Sicilian immigrant parents in the Little Italy neighborhood of Baltimore; he had 10 children (five sons and five daughters) and 37 grandchildren, one of whom (a cousin of Luigi) is Nino Mangione, a member of the Maryland House of Delegates. After Nicholas Mangione's death, his children took over his businesses; Luigi's father now runs the Mangione Family Enterprises. The extended family also owns Hayfields Country Club, Turf Valley Resort, Lorien Health Services, the WCBM radio station, as well as the Mangione Family Foundation.
Mangione attended Gilman School, an all-boys private school in Baltimore, where he graduated as valedictorian in 2016. Mangione received a Bachelor of Science in Engineering (BSE) in computer engineering and a Master of Science in Engineering (MSE) in computer and information science from the University of Pennsylvania in 2020. His undergraduate studies included a minor in mathematics, and his graduate curriculum was concentrated in artificial intelligence. He was a UI programming intern with the video game company Firaxis Games from May 2016 to August 2017 while he was an undergraduate student.
Mangione began to work remotely in November 2020 as a data engineer for TrueCar, a car retailing website company headquartered in Santa Monica, California. His employment there ended at some point during 2023, according to the company. His last known residence was in Honolulu, Hawaii.
Alleged role in the killing of Brian Thompson
Background
Brian Thompson, CEO of the American health insurance company UnitedHealthcare, was shot and killed in Midtown Manhattan, New York City, on December4, 2024. The shooting occurred early in the morning outside an entrance to the New York Hilton Midtown hotel. Thompson was in the city to attend an annual investors' meeting for UnitedHealthcare's parent company UnitedHealth Group. The suspect, initially described as a white man wearing a mask, fled the scene.
The gunman was masked and had come to New York via a bus from Atlanta. The words "delay", "deny", and "depose" were written on the spent cases and an ejected cartridge. The three words are similar to the phrase "delay, deny, defend", a well-known phrase in the insurance industry alluding to insurance companies' efforts to not pay out claims. The suspect possibly left the city, being seen at a bus terminal afterward. Anger erupted on social media platforms at Thompson, UnitedHealth, and the health insurance system generally, with many praising the killing.
Arrest
On December 9, 2024, local police arrested Mangione at a McDonald's restaurant in Altoona, Pennsylvania, responding to a call from an employee made in response to a customer who suspected similarities between Mangione's appearance and images of Thompson's alleged killer released by the New York City Police Department (NYPD). Altoona is about west of New York City. The police reported that he was "visibly shaken" when they asked him if he had recently visited New York City.
Upon searching Mangione, police said they found a similar 3D-printed gun and 3D-printed suppressor to the weapons used in the shooting and a fake driver's license from New Jersey with the name "Mark Rosario", the same name used by the alleged shooter to check into a Manhattan hostel. Shell casings found at the crime scene reportedly matched the gun. The police also said that, when they arrested Mangione, they found a 262-word handwritten document partly about the American healthcare system, which was characterized as a manifesto by multiple media outlets. Mangione had no prior criminal record.
State and federal charges
Mangione was charged in Blair County, Pennsylvania, with carrying a gun without a license, forgery, falsely identifying himself to the authorities, and possessing "instruments of crime" on December 9, 2024. He was arraigned at around 6 p.m. at Blair County Courthouse on firearms charges, questioned by the NYPD, and denied bail. As he was led into the courthouse, Mangione shouted to the gathered cameras: "That's completely out of touch and is an insult to the intelligence of the American people and their lived experience."
Later that day, Mangione was charged in Manhattan with second-degree murder, three counts of illegal weapons possession, and forgery and sent to the State Correctional Institution at Huntingdon, a close-security state correctional facility in Huntingdon County, Pennsylvania.
On December 17, 2024, Mangione was indicted on eleven New York state charges by the Manhattan district attorney's office.
Murder in the first degree (murder in furtherance of an act of terrorism as defined under the Anti-Terrorism Act of 2001)
Murder in the second degree as a crime of terrorism (a crime of terrorism under the Anti-Terrorism Act of 2001, in the form of murder)
Murder in the second degree (murder as such – intentional killing)
Criminal possession of a weapon in the second degree (possession of a loaded firearm with intent to use the same unlawfully against another)
Criminal possession of a weapon in the second degree (unlicensed carrying of a loaded firearm)
Criminal possession of a weapon in the third degree (possession of an "assault weapon" under the gun laws in New York)
Criminal possession of a weapon in the third degree (silencer)
Criminal possession of a weapon in the third degree (Glock magazine)
Criminal possession of a weapon in the third degree (Magpul magazine)
Criminal possession of a weapon in the fourth degree (3D-printed gun)
Criminal possession of a forged instrument in the second degree (fake ID)
On December 19, 2024, Mangione received an additional four federal charges. Possible remedies for murder by firearm include execution.
Stalking (interstate via traveling from Georgia to New York) (18 U.S.C. ss. 2261A(1)(A) and 22661(b)(1))
Stalking (interstate via use of a cellphone and the Internet) (18 U.S.C. ss. 2261A(1)(A) and 22661(b)(1))
Murder through use of a firearm (18 U.S.C. s. 924(j)))
Firearms offense (18 U.S.C. s. 924(c)(1)(A)(i), (ii), (iii) and (c)(1)(B)(ii))
Mangione was extradited to New York and is currently being held at Metropolitan Detention Center, Brooklyn.
In a press release from the U.S. Attorney's Office Southern District of New York concerning the unsealing of the Complaint charging Mangione, they state "The charges contained in the Complaint are merely accusations, and the defendant is presumed innocent unless and until proven guilty."
On December 23, Mangione was arraigned in the New York Supreme Court and pleaded not guilty to his state charges.
Defense
Mangione's Pennsylvania attorney Thomas Dickey said that Mangione would plead not guilty to all the charges against him. Mangione hired Karen Friedman Agnifilo, former prosecutor at the Manhattan District Attorney's Office and former legal analyst with CNN, as his New York case defense attorney on December 13. Ten days later, Mangione was flown to New York after waiving his right to an extradition hearing.
On December 13, the crowdfunding platform GoFundMe removed a fundraiser created by Mangione's supporters to cover his legal costs. The site's Terms of Service prohibits fundraisers for the legal defense of violent crimes, and it was removed; a GiveSendGo fundraiser has remained live, and, by December 24, 2024, it had raised more than .
Personal life
Mangione wrote online that he suffers from spondylolisthesis and Lyme disease. He allegedly underwent a spinal fusion surgery in July 2023. Police stated that Mangione was not insured by UnitedHealthcare.
In the summer of 2024, Mangione stopped posting on social media. On November 18, 2024, his mother reported him missing to the San Francisco Police Department, saying the family had not heard from him since July of that year, shortly after a trip to East and Southeast Asia. Mangione's mother contacted the San Francisco Police Department because she believed that Mangione lived in San Francisco and still worked for TrueCar, which had an office there.
Views
Handwritten letter
Upon Mangione's arrest, police said they found in his possession a 262-word handwritten document, which some media outlets characterized as a "manifesto", that, according to NYPD commissioner Jessica Tisch, spoke to Mangione's "motivation and mindset".
Ken Klippenstein is the only journalist to publish what was alleged to be the entire document police said was found on Mangione:
To the Feds, I'll keep this short, because I do respect what you do for our country. To save you a lengthy investigation, I state plainly that I wasn't working with anyone. This was fairly trivial: some elementary social engineering, basic CAD, a lot of patience. The spiral notebook, if present, has some straggling notes and To Do lists that illuminate the gist of it. My tech is pretty locked down because I work in engineering so probably not much info there. I do apologize for any strife of traumas but it had to be done. Frankly, these parasites simply had it coming. A reminder: the US has the #1 most expensive healthcare system in the world, yet we rank roughly #42 in life expectancy. United is the [indecipherable] largest company in the US by market cap, behind only Apple, Google, Walmart. It has grown and grown, but as our life expectancy? No the reality is, these [indecipherable] have simply gotten too powerful, and they continue to abuse our country for immense profit because the American public has allowed them to get away with it. Obviously the problem is more complex, but I do not have space, and frankly I do not pretend to be the most qualified person to lay out the full argument. But many have illuminated the corruption and greed (e.g.: Rosenthal, Moore), decades ago and the problems simply remain. It is not an issue of awareness at this point, but clearly power games at play. Evidently I am the first to face it with such brutal honesty.
However, the Complaint filed by the U.S. Attorney's office states "The Feds Letter also stated: 'P.S. you can check serial numbers to verify this is all self-funded. My own ATM withdrawals. which is not shown in the document that was released by Klippenstein.
Analysis of social media presence
Several news outlets analyzed Mangione's social media in the wake of his arrest and drew conclusions on his social, political, and religious views. His posts were found to express concerns over the implications of pornography, DEI programs, falling fertility rates, wokeism, secularization, and the decline of Christianity, and he promoted traditionalist ideas. He leans in favor of religion in general on evolutionary grounds, opposing New Atheism and has expressed interest in Japan's indigenous religion, Shintoism. Mangione showed a skeptical attitude toward both Joe Biden and Donald Trump. Multiple sources have reported that he followed Democratic Representative Alexandria Ocasio-Cortez as well as Robert F. Kennedy Jr. and others, labeling him as politically uncategorized and "anti-system".
According to Business Insider, Mangione's since-deleted social media posts supported the idea that "his worldview was influenced by reactionary right-wing thinkers". Time magazine said it could not discern whether his political views were left- or right-wing. The Spectator wrote that his worldview "wasn't pinned to a standard left-right axis". Jacobin stated that he held "a hodgepodge of views and political beliefs that don't neatly map onto any one category on the political spectrum".
Mangione posted a Goodreads review of Ted Kaczynski's Industrial Society and Its Future, describing Kaczynski as "rightfully imprisoned" and criticizing his use of violence against innocent individuals. The review was quoted as writing, "Clearly written by a mathematics prodigy. Reads like a series of lemmas on the question of 21st century quality of life", and "It's easy to quickly and thoughtless write this off as the manifesto of a lunatic, in order to avoid facing some of the uncomfortable problems it identifies [...] but it's simply impossible to ignore how prescient many of his predictions about modern society turned out." The review, which gave the manifesto four out of five stars, also contained a quote that the reviewer claimed to have found online. The quote contained the lines Violence never solved anything' is a statement uttered by cowards and predators" and "when all other forms of communication fail, violence is necessary to survive".
Robert Evans described Mangione as being associated with a loosely-defined online subculture called the "gray tribe" or the "rationalist movement", whose members he described as "self-consciously intellectual and open-minded, [and] preoccupied with learning how to overcome their own mental biases. They're deliberately eclectic in their information diet, invoking esoteric ideas from many different fields, [and are] often systems thinkers, who take pride in attributing social problems not to individual evil but to complex interplays of incentives and institutions".
Public image
Following the Thompson shooting, the suspected shooter was celebrated as a folk hero by many social media users. Look-alike contests have been held in New York City's Washington Square Park and at the University of Florida.
After Mangione's arrest, he received support and praise on social media and over 460,000 followers after his identification on Twitter. According to the Network Contagion Research Institute, variations of "#FreeLuigi" have been shared over 50,000 times on Twitter after his arrest. Groups of people gathered outside the Blair County Courthouse and Manhattan Criminal Court to show their support for Mangione during his December court hearings. The support Mangione has generated has been connected to the public's often negative view of the health insurance industry and what many consider to be unfair claim denial practices that inflict harm. The case has spurred growing calls for health insurance reform. A December 2024 NORC at the University of Chicago poll found that a majority of American adults believe that health insurance company denials for health care coverage and/or profits made by those companies share a moderate amount or a great deal of responsibility for Thompson's death.
Street art, graffiti, and signs in support of Mangione appeared on buildings, streets, highways, and other places. A billboard with the words "Free Luigi" was seen in Riverside County, California, and a mural portraying Mangione as the Nintendo character Luigi was seen in Seattle. Images and memes of Mangione depicted as a Roman Catholic saint have circulated online. Items and merchandise in support of Mangione were posted on Etsy, Amazon, and other e-commerce sites before being removed. Some merchandise were reportedly the subject of copyright and DMCA takedown requests from an entity purporting to be UnitedHealth Group Inc. Other social media users linked Mangione's jail commissary account soliciting donations for "snacks, sodas, an iPad, etc." The Independent reported that, during his time in custody in Pennsylvania, Mangione had received over 100 pieces of mail.
Mangione has been noted for his perceived physical attractiveness, and Kara Alaimo, writing for Time, stated that he has become "somewhat of an online sex symbol". After Mangione's Manhattan courtroom appearance on December 23, Maison Margiela trended on Twitter and Threads after social media users misidentified the brand of the burgundy sweater that Mangione was wearing. Users later determined that he was wearing a "washable Merino crewneck sweater" from Nordstrom, which social media users nicknamed 'Mangione Merino', quickly selling out. A criminal justice professor, speaking about Mangione's online popularity, told Women's Wear Daily that "What we see with Mangione is he has quickly become a folk hero and a fashion folk hero."
Perp walk
After being transported from Pennsylvania to New York on December 19, Mangione received a highly publicized perp walk, escorted by a large number of heavily armed law enforcement officials and Mayor of New York City Eric Adams. Stanford Law School professor Robert Weisberg said that "The FBI and NYDA could have transported Mangione discreetly, but they opted for a public show", and some legal experts stated that the perp walk was a "blatant and unnecessary attempt at self-promotion". Policy director for the Justice Collaboratory at Yale Law School Jorge Camacho said that, "in a case like Mangione's, where the suspect has garnered some sympathy and applause from people frustrated with greedy health-care insurance companies, the tactic can backfire".
Some social media users shared memes and compared Mangione's perp walk to the arrest of Jesus, scenes from the Superman movies, and Renaissance paintings. On December 23 during Mangione's New York court hearing where he pled not guilty to the state charges, his defense attorney Karen Friedman Agnifilo said that Mangione might not receive a fair trial due to publicity from law enforcement presentations of him, blaming Mayor of New York City Eric Adams for the "unnecessary" and "utterly political" perp walk. She added, "The mayor should know more than anyone about the presumption of innocence", suggesting Adams was attempting to distract from the charges he himself is facing.
Opinion polls
An Economist/YouGov poll conducted from December 15 to 17 surveying 1,553 U.S. adult citizens found that 43% of American citizens had a "somewhat unfavorable" or "very unfavorable" view of Mangione, while 21% had a "somewhat favorable" or "very favorable" view of him. 37% were unsure. Mangione received the most support from citizens aged 18–29, who viewed him favorably by a 39%–29% margin, and very liberal citizens, who viewed him favorably by a 47%–31% margin. Mangione was viewed least favorably by citizens aged 65 and older (65%–5% unfavorable) and very conservative citizens (62%–8% unfavorable).
The Center for Strategic Politics ran an online poll with 455 American adults on December 11 and found that "61% of respondents said they have a strong or somewhat negative perception of Mangione", 19% had a positive or somewhat positive view, and 21% did not know. Opinions on Mangione vary "dramatically" by age, with respondents under 45 holding a more positive view of him than those over 45. Additionally, they indicated that men were more likely to support Mangione than women, and Black and Hispanic respondents were more likely to support him than White respondents. The poll also found that young Americans view Mangione "far more favorably" than they viewed Thompson and UnitedHealthcare.
A poll of 6,000 U.S. adults was conducted by CloudResearch on December 19, utilizing artificial intelligence (AI). The poll found that roughly one in four respondents were sympathetic to Mangione.
In popular culture
Mangione was referenced in various season 50 sketches of the American sketch comedy late-night television series Saturday Night Live. He was mentioned in the Weekend Update segments with anchors Colin Jost and Michael Che; in his opening monologue, comedian Chris Rock joked about the capture of Mangione; in another sketch, Nancy Grace (played by Sarah Sherman) expressed disbelief at the online support of Mangione and interviews a regular Pennsylvania McDonald's customer (played by Kenan Thompson) and an alleged Mangione look-alike (played by Emil Wakim).
Popularity and admiration of Mangione online brought a revival of the former internet meme "Luigi Death Stare" among comments replying to online posts concerning the development of an American oligarchy.
Vulture reported that documentaries about Mangione are in development. One documentary is being developed by Alex Gibney and Anonymous Content, and the other by Stephen Robert Morse.
Notes
References
External links
Commonwealth v. Mangione
Ken Klippenstein: Read the NYPD’s Mangione report the media won't publish
1998 births
21st-century American engineers
21st-century prisoners and detainees of the United States federal government
American people of Italian descent
American prisoners and detainees
American software engineers
American video game programmers
Data engineers
Gilman School alumni
Internet memes introduced in 2024
-
Living people
People charged with murder
People charged with terrorism
People from Honolulu
People from Towson, Maryland
People of Sicilian descent
Prisoners and detainees of New York (state)
Prisoners and detainees of Pennsylvania
University of Pennsylvania School of Engineering and Applied Science alumni | Luigi Mangione | [
"Engineering"
] | 4,705 | [
"Data engineers",
"Data engineering"
] |
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