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72,131,716 | https://en.wikipedia.org/wiki/Costa%20Rican%20Space%20Agency | Costa Rican Space Agency is a space research and development bureau based in San Jose, Costa Rica, and was founded by the Constitutional Congress of Costa Rica. It is the first space agency to be created and operated by a Central American nation.
In 2018, their first satellite, Irazu, was launched
References
Space agencies
Institutions of Costa Rica | Costa Rican Space Agency | [
"Astronomy"
] | 68 | [
"Outer space stubs",
"Outer space",
"Astronomy stubs"
] |
72,131,741 | https://en.wikipedia.org/wiki/Pterula%20multifida | Pterula multifida is a species of mushroom producing fungus in the family Pterulaceae.
Taxonomy
It was first described in 1861 by the Swedish mycologist Elias Magnus Fries who classified it as Pterula multifida based on specimens he had found in 1857.
François Fulgis Chevallier's Penicillaria multifida may be confused with this in the taxonomic history due to the identical abbreviation of P. multifida. However this is unrelated and Penicillaria multifida is now a nomen superfluum and considered illegitimate. Penicillaria multifida was a reclassification of Pierre Bulliard's Clavaria penicillata and that species did go to be reclassified as another Pterula species however in 1930 when Fries classified it as Pterula penicillata.
Pterula multifida var. densissima was described in 1958 by the Czech mycologist Albert Pilát. The citation he gave for this variant was 'B. et C. 1873' and in the same text he also wrote 'Pterula densissima Berk. et Curt. 1873' which has led to Pterula densissima being listed as a synonym of Pterula multifida. However the taxonomic records for this likewise have some citation errors so they remain unclear.
Description
Pterula multifida is a small whitish coral fungus with a delicate branching structure.
Fruit body: 1-5mm thin, hairlike coral that branches repeatedly towards the smooth and shiny pointed tips. The colour is white to off white to light brown with the tips having a lighter colour than the base. Stem: 0.05–0.1mm when present but sometimes absent. Flesh: White. Tough and rubbery. Spore print: White. Spores: Ellipsoid and smooth. 5–6 x 2.5–3.5μm. Taste: Indistinct. Smell: Indistinct or unpleasant like urea or chemicals.
Habitat and distribution
The specimens observed by Fries were found growing on sprigs of Spruce on the ground in the Uppsala Botanical Garden, Sweden in 1857.
In 1873 this species was included in Charles Montague Cooke's list of British fungi citing a specimen documented by Miles Joseph Berkeley and Christopher Edmund Broome which had been communicated to them by Walter Calverley Trevelyan. However it was noted that they were 'unable at present to meet with a description of this plant'.
This species is not commonly recorded in the United Kingdom but has been found in Berkshire, East & West Norfolk, Northamptonshire, North Somerset, South Devon, Surrey, Warwickshire and Glamorganshire in Wales. It occurs on damp soil and leaf litter in woodlands and has been found growing on the fallen catkins of Salix species (willow trees) and on needles from Picea species (spruce). It has also been found on the dead stems of the grass species Juncus subnodulosus, ferns such as Polystichum and on the dead stems of Rose and Rubus fruticosus (blackberries). It grows solitary or in small trooping groups from late Summer to Autumn in England.
, GBIF has around 1,250 recorded observations for this species with most being from Europe. However many of there are just observations from citizen science platforms and lack evidence to confirm. Due to the similarities with other Pterula species some may also have been confused.
Etymology
The specific epithet multifida derives from the Latin multifidus meaning 'with many divisions'.
Similar species
Pterula subulata is described very similarly.
References
Pterulaceae
Fungi described in 1861
Fungi of Europe
Fungus species | Pterula multifida | [
"Biology"
] | 757 | [
"Fungi",
"Fungus species"
] |
72,131,781 | https://en.wikipedia.org/wiki/Liquid%20phase%20exfoliation | First demonstrated in 2008, liquid-phase exfoliation (LPE) is a solution-processing method which is used to convert layered crystals into two-dimensional nanosheets in large quantities. It is currently one of the pillar methods for producing 2D nanosheets. According to IDTechEx, the family of exfoliation techniques which are directly or indirectly descended from LPE now make up over 60% of global graphene production capacity.
This method involves adding powdered layered crystals, for example of graphite, to appropriate solvents and inserting energy, often by ultrasonication, although high-shear mixing is often commonly used. The addition of energy causes a combination of fragmentation and exfoliation resulting in the removal of small nanosheets from the layered crystals. In this way graphite can be converted into large quantities of graphene nanosheets. In general, these nanosheets tend to be a few monolayers thick and of lateral sizes ranging from tens of nanometers to many microns. These dispersed nanosheets form quasi stable suspensions so long as solvents used have surface energies similar to that of the nanosheets. Dispersed concentrations of order 1 gram per litre can be achieved. In addition to solvents, it is also possible to use molecular stabilizers, for example surfactants or polymers to coat the nanosheets and stabilise them against regaggregation. This has the advantage that it allows nanosheets to be suspended in water.
Although this method was first applied to exfoliate graphite to yield graphene nanosheets, it has since been used to produce a wide range of 2D materials including molybdenum disulfide, tungsten diselenide, boron nitride, nickel(II) hydroxide, germanium monosulfide, SnP3, and black phosphorus. The liquid suspensions produced by liquid phase exfoliation can be used to create a range of functional structures. For example, they can be printed into thin films and networks using standard techniques such as inkjet printing.
Printed structures have been used in a range of applications in areas included printed electronics, sensors and nanocomposites. Related methods include exfoliation by wet ball milling, homogenization, microfluidization and wet jet milling. Liquid phase exfoliation is different from other liquid exfoliation methods, for example the production of graphene oxide, because it is much less destructive, leaving minimal defects in the basal planes of the nanosheets. It has recently emerged that LPE can also be used to convert non-layered crystals into quasi-2D nanoplatelets.
Origins
Liquid phase exfoliation was first described in detail in a paper by a research team in Ireland in 2008, although a very short description of a similar process was published by the Manchester group around the same time. While other papers had previously described methods to exfoliate layered crystals in liquids, these papers were the first to describe exfoliation in liquids without any previous ion intercalation or chemical treatment.
Exfoliation methods
LPE involves inserting layered crystals into appropriate stabilizing liquids and then adding energy to remove nanosheets from the layered crystals. A number of different methods have been used to supply energy to the liquid. The earliest and most common is ultrasonication. In order to scaleup the process, high shear mixing was introduced in 2014. This method proved extremely useful and inspired a number of other methods of generating shear in the suspension, including wet ball milling, homogenization, microfluidization and wet jet milling.
Stabilisers
The simplest stabilizing liquids are solvents with surface energy close to the layered crystal being exfoliated. In practice, liquids with surface tensions close to 70 mJ/m2 are used. In addition aqueous surfactant solutions are often used. Less common, but useful for certain applications, is using molecular or polymeric additives to stabilise the exfoliated nanosheets.
LPE of 2D materials beyond graphene
A very wide range of 2D materials have been produced by LPE. The first material to be exfoliated was graphene in 2008. This was followed in 2011 by the exfoliation of BN, MoS2 and WS2. Since, the a wide range of 2D materials have been exfoliated including molybdenum diselenide, tungsten diselenide, gallium sulphide, molybdemum trioxide, nickel(II) hydroxide, germanium monosulfide, SnP3, black phosphorus etc.
LPE of non-layered materials
Recent work has shown that liquid phase exfoliation can be used to produce 2D-nanoplatelets from non-layered 3D-strongly bonded bulk materials. This is intuitively unexpected as these 3D-solid bulk crystals consists of strong bonds in all the three-directions. Nevertheless, many non-layered materials such as boron, silicon, germanium, iron disulfide, iron oxide, iron trifluoride, manganese telluride, have been converted to 2D nanoplatelets when sonicated in appropriate solvents. This raises many open questions on the mechanism of liquid-phase exfoliation process. For layered materials, the energy required to break inter-plane (perdominately van der Waals) bonds forces is small compared to that required to break in-plane ionic or covalent bonds. Then, the exfoliation procedure results in the formation of 2D-nanosheets. However, for non-layered 3D-strongly bonded materials, with minimal difference in bonding between different atomic planes, there is no "easily exfoliated" direction and sonication should yield quasi spherical particles. Nevertheless, near isotropic materials such as silicon have been exfoliated to give high-aspect ratio platelets. Therefore, developing an understanding of the mechanisms by which non-layered materials are exfoliated will be important, in particular because the application scope of such nonlayered 2D-nanoplatelets is broad, ranging from biomedical applications to energy storage to opto-electronics.
References
Chemical physics
Laboratory techniques | Liquid phase exfoliation | [
"Physics",
"Chemistry"
] | 1,268 | [
"nan",
"Applied and interdisciplinary physics",
"Chemical physics"
] |
72,132,263 | https://en.wikipedia.org/wiki/Pterulicium%20caricis-pendulae | Pterulicium caricis-pendulae is a species of mushroom producing fungus in the family Pterulaceae. It has the common name pendulous sedge club.
Taxonomy
It was first described in 1970 by Edred John Henry Corner who classified it as Pterula caricis-pendulae.
In 2020 the Pterulaceae family was reclassified based on phylogenetic analysis and many species were split into Pterula, Myrmecopterula, Pterulicium and Phaeopterula genera. This species was one of them and was reclassified as Pterulicium caricis-pendulae by the mycologists Caio A. Leal-Dutra, Bryn Tjader Mason Dentinger and Gareth W. Griffith in 2020.
Description
Pterulicium caricis-pendulae is a small whitish coral fungus with a delicate branching structure.
Fruit body: 0.5-2mm thin, hairlike coral that is sparsely branched with smooth and shiny pointed tips. Stem: Absent. Flesh: White. Tough and rubbery. Spore print: White. Spores: Elongated ellipsoid and smooth. 5.5-7.5 x 3-4μm. Basidia: 4-spored. Taste: Indistinct. Smell: Indistinct.
Habitat and distribution
This species is not commonly recorded in the United Kingdom and is on the Red List as a near threatened species. It has been found in woodland and marshes growing on decaying debris from the Carex pendula sedge as well as Juncus rushes and Symphytum. It grows solitary or in small trooping groups.
, GBIF has fewer than 20 recorded observations for this species with most being from Europe.
Etymology
The specific epithet caricis-pendulae derives from the Latin 'caricinus' meaning like sedge (Carex) and 'pendulus' meaning hanging.
Similar species
Pterulicium gracile is described similarly and is distinguished based on microscopic characteristics.
References
Pterulaceae
Fungi described in 1970
Fungi of Europe
Fungus species | Pterulicium caricis-pendulae | [
"Biology"
] | 447 | [
"Fungi",
"Fungus species"
] |
72,132,337 | https://en.wikipedia.org/wiki/Elfriede%20Tungl | Elfriede Tungl (4 July 1922 – 25 August 1981) was an Austrian civil engineer. She was the first Austrian woman to earn a doctorate in civil engineering and in 1973 became the first female associate professor at the Vienna University of Technology.
Early life and education
Elfriede Tungl was born on 4 July 1922 in Vienna.
Tungl enrolled in mathematics, physics and chemistry at the University of Vienna in 1940, but changed subjects after one year and studied civil engineering, graduating from the TU Wien in 1948. She received her doctorate from the TU Wien (Vienna University of Technology) in 1950. Tungl started work in the bridge construction department of the General Directorate of the Austrian Federal Railways, the ÖBB.
In 1952, she became a university research assistant working on issues related to the theory of structural systems. In 1963, her habilitation (post doctorate degree) at the Vienna University of Technology looked at the fields of elasticity and material strength theory. Tungl was the second woman to habilitate at this university, and the first woman to habilitate in these fields. She is thought to have been the first female civil engineer in Europe to hold a doctorate.
Career
Tungl taught as a visiting professor in the US from 1965 to 1968, and in 1973 she became the first woman to be appointed associate professor at the Vienna University of Technology. She became head of the department of experimental Spannungs- und Dehnungsmessung, (stress and strain measurement) until she retired for health reasons in 1975.
Tungl died in Vienna on 25 August 1981.
References
Further reading
Helga Eberwein: Tungl Elfriede. Korotin (ed), Ilse. fwf.ac.at biografiA. Lexikon österreichischer Frauen, Band 3: Band 03, P-Z]. Vol. Band 3: P–Z. Böhlau. p. 3340.
1922 births
1981 deaths
TU Wien alumni
Bridge engineers
Austrian engineers
Austrian academics
Women engineers
Austrian women engineers
TU Wien
Civil engineers
Austrian civil engineers
Engineers from Vienna
20th-century Austrian engineers | Elfriede Tungl | [
"Engineering"
] | 431 | [
"Civil engineering",
"Civil engineers"
] |
72,132,499 | https://en.wikipedia.org/wiki/Pterulicium%20gracile | Pterulicium gracile is a species of mushroom producing fungus in the family Pterulaceae.
Taxonomy
This species has a long and complex taxonomic history owing to there being multiple basionyms during the 1800s each of which was reclassified multiple times before ultimately being merged. Amongst others, it has previously been classified as a Typhula or Clavaria species owing to the similar colour, form and diminutive size members of this genus have. The large number of synonyms this species has a result of all these reclassifications speaks to both how often it was found and the lack of significant distinguishing features to separate it neatly from other coral fungi.
The earliest classification of this species was as Typhula gracilis in 1838 by John Baptiste Henri Joseph Desmazières and Miles Joseph Berkeley so the specific epithet gracilis is the one that was retained.
In 1950 the species was reclassified as Pterula gracilis by the British mycologist Edred John Henry Corner. At the time he considered Ceratellopsis rickii and Ceratellopsis tremula to be distinct species however these are now regarded as synonyms.
In 2020 the Pterulaceae family was reclassified based on phylogenetic analysis and many species were split into Pterula, Myrmecopterula, Pterulicium and Phaeopterula genera. This species was one of them and was reclassified as Pterulicium gracile by the mycologists Caio A. Leal-Dutra, Bryn Tjader Mason Dentinger and Gareth W. Griffith in 2020.
Description
Pterulicium gracile is a small whitish coral fungus with a delicate branching structure.
Fruit body: 2-10mm thin, hairlike coral that is densely crowded and sometimes forks towards the smooth and shiny pointed tips. Stem: 0.5-1mm but may be absent. Flesh: White. Tough and rubbery. Spore print: White. Spores: Elongated ellipsoid and smooth. 5.5-7.5 x 3-4μm. Basidia: 2-spored. Taste: Indistinct. Smell: strong and unpleasant like chemicals.
Habitat and distribution
This species is not commonly recorded in the United Kingdom and is said to be widespread but rarely reported. It has been founded on decaying vegetable matter, leaves and the stems of herbaceous plants in deciduous woodland and marshes. Though it may grow on other plant matter. It grows solitary or in small trooping groups.
, GBIF has fewer than 100 recorded observations for Pterulicium gracile and around 200 for the previous taxon Pterula gracilis. Most of these are from Europe.
Etymology
The specific epithet gracile (originally gracilis) derives from the Latin 'gracilis' meaning graceful.
Similar species
Pterulicium caricis-pendulae is described similarly and is distinguished based on microscopic characteristics.
References
Pterulaceae
Fungi described in 1838
Fungi of Europe
Fungus species | Pterulicium gracile | [
"Biology"
] | 627 | [
"Fungi",
"Fungus species"
] |
72,133,644 | https://en.wikipedia.org/wiki/Journal%20of%20Sustainable%20Development%20of%20Energy%2C%20Water%20and%20Environment%20Systems | The Journal of Sustainable Development of Energy, Water and Environment Systems is a quarterly peer-reviewed open-access scientific journal covering sustainability studies. The editor-in-chief is Neven Duić (University of Zagreb).
Abstracting and indexing
The journal is abstracted and indexed in the Emerging Sources Citation Index and Scopus. According to the Journal Citation Reports, the journal has a 2022 impact factor of 2.1.
References
External links
Sustainability journals
Academic journals established in 2013
English-language journals
Quarterly journals
Creative Commons Attribution-licensed journals | Journal of Sustainable Development of Energy, Water and Environment Systems | [
"Environmental_science"
] | 112 | [
"Environmental science journals",
"Sustainability journals"
] |
62,503,788 | https://en.wikipedia.org/wiki/Carleman%20linearization | In mathematics, Carleman linearization (or Carleman embedding) is a technique to transform a finite-dimensional nonlinear dynamical system into an infinite-dimensional linear system. It was introduced by the Swedish mathematician Torsten Carleman in 1932. Carleman linearization is related to composition operator and has been widely used in the study of dynamical systems. It also been used in many applied fields, such as in control theory and in quantum computing.
Procedure
Consider the following autonomous nonlinear system:
where denotes the system state vector. Also, and 's are known analytic vector functions, and is the element of an unknown disturbance to the system.
At the desired nominal point, the nonlinear functions in the above system can be approximated by Taylor expansion
where is the partial derivative of with respect to at and denotes the Kronecker product.
Without loss of generality, we assume that is at the origin.
Applying Taylor approximation to the system, we obtain
where and .
Consequently, the following linear system for higher orders of the original states are obtained:
where , and similarly .
Employing Kronecker product operator, the approximated system is presented in the following form
where , and and matrices are defined in (Hashemian and Armaou 2015).
See also
Carleman matrix
Composition operator
References
External links
A lecture about Carleman linearization by Igor Mezić
Dynamical systems
Functions and mappings
Functional analysis
Eponyms in mathematics | Carleman linearization | [
"Physics",
"Mathematics"
] | 287 | [
"Mathematical analysis",
"Functions and mappings",
"Functional analysis",
"Mathematical objects",
"Mechanics",
"Mathematical relations",
"Dynamical systems"
] |
62,504,894 | https://en.wikipedia.org/wiki/WD%20J0914%2B1914 | WD J0914+1914 is the first single white dwarf star found to have a giant planet orbiting it. Evidence of the giant planet was discovered by a team of astronomers from the UK, Chile and Germany.
The system was initially identified as a cataclysmic variable on the basis of weak H-alpha emissions in the spectrum by the Sloan Digital Sky Survey (SDSS). After closer inspection the team of astronomers discovered oxygen and sulfur lines in the SDSS spectra. The team then obtained spectroscopic follow-up observations with X-Shooter on ESO's Very Large Telescope. The spectra confirmed the previous observations by SDSS and found additional lines.
Planets
Dusty and gaseous debris disks around white dwarfs are known, but they are dominated by calcium lines and no previous disk around a white dwarf showed Hα emission. All previous disks around white dwarfs originate from rocky planetary bodies. The size of the disk around WD J0914+1914 was measured with the help of Doppler-broadbanded emission lines. The disk around the white dwarf is too large (~1-10 solar radii) to be formed by a small minor planet, which was tidally disrupted inside the Roche Radius. The team was also able to exclude accretion of material from a companion star or brown dwarf.
The most plausible explanation is an evaporating giant planet, orbiting close to the white dwarf. The atmosphere of the planet is evaporated by the strong ultraviolet radiation of the hot white dwarf. The planet is likely to be about 15 solar radii from the white dwarf and orbits it in 10 days. The composition of the accreted material shows similarity to certain deeper layers of the ice giants in the solar system. The team estimated that the planet around WD J0914+1914 will, over the span of about 350 million years, lose about 0.04 Neptune masses, a negligible amount. Meanwhile, the dwarf will continue to cool.
See also
List of exoplanets and planetary debris around white dwarfs
WD 1145+017
ZTF J0139+5245
References
External links
https://www.space.com/alien-planet-detected-around-white-dwarf-first-discovery.html
White dwarfs
Astronomical objects discovered in 2019
Cancer (constellation)
Hypothetical planetary systems
Gas giants
Orion–Cygnus Arm
Cataclysmic variable stars | WD J0914+1914 | [
"Astronomy"
] | 492 | [
"Cancer (constellation)",
"Constellations"
] |
62,507,108 | https://en.wikipedia.org/wiki/Engineer%20Command%20%28Italy%29 | The Engineer Command () in Rome-Cecchignola commands the specialized engineer regiments of the Italian Army and it is tasked with training of all officers and troops destined for engineer units, as well as with both doctrinal and operational tasks.
The Engineer Command was established in 2010 and underwent a series of reorganizations, shifting from a Brigade-level command to a Division-level element. Nowadays, it keeps the traditions and the honours of the Arm of Engineers, and its commander is the Inspector of the Arm of the Engineers.
History
The Engineer Command of the Italian Army was established on 10 September 2010, but it traces its origins back to the Engineer Brigade (based in Udine) and the Engineer School in Rome.
Engineer School
The Pioneers Engineer School was established on 10 March 1950 in Rome. However, the School was heir to two further training institutes: the Central Engineer School and the Reserve Officers School of Engineers.
The Engineers Central School was established in Manziana as a result of the decree of 18 January 1920 (moved to Civitavecchia in 1925). The School had the task of training the non-commissioned officers and training the troops in the various specialties of the Engineers: sappers, miners, cable operators, photoelectricists, telegraphers and radiotelegraphers. The School also held refresher courses for senior officers and captains about to be promoted as well as training courses for reserve officers called back in service.
The School of Engineer Reserve officer cadets of was created by decree of 1 May 1930 in Verona (moved to Pavia in 1936).
The Italian Civil War forced both two schools to suspend their activities. In 1944 three training bodies were established:
Italian School of Radio-Telegraph Connections in Nocera Inferiore;
Telegraph School in Francavilla Fontana;
232nd Workers Battalion in Bracciano.
In 1948 the School reopened the courses for Reserve officer cadets. In January 1949, a Specialized Battalion and the Reserve officer cadets Company were transferred to Rome Cecchignola in the “Ettore ROSSO” barracks, giving life to the training nucleus of the Pioneers Engineer School established there on 10 March 1950.
In March 1954 a Training Battalion based in Civitavecchia was assigned to the School. The Battalion was tasked with training conscripts. The School also had the task of training the first nuclei of the Italian special forces for the pioneering part. In November 1955, the Battalion stationed in Civitavecchia was transferred to Rome to the "Bazzani" Barracks, also to the Cecchignola, and subsequently in November 1961 to the "E. Rosso ”where it assumed the name of III Specialized Battalion.
Engineers Brigade
The Engineers Brigade was formed, as Engineers Grouping Command, on 1 December 1997, by transforming the pre-existing Engineers Command of the 5th Army Corps. Assigned to the Operational Land Forces Support Command, the Engineers Grouping Command controlled:
6th Pioneer Regiment;
11th Engineer Regiment;
21st Engineer Regiment;
2nd Pontieri Engineer Regiment;
5th Engineer Battalion "Bolsena".
In the nineties it took over the Ferrovieri Engineers Regiment. At the end of the decade the Brigade lost the 11th and 21st Pioneer Engineers Regiments and the 5th Battalion.
The Engineer Brigade provided disaster relief and reconstruction support in natural and man-made emergencies in Italy.
Engineer Command
The Engineer Command of the Italian Army was established on 10 September 2010 as one star-rank command under the Support Command of the Land Operational Forces (SUPPORTI FOTER). On 1 February 2011, the Obstacle Training Center was renamed to the C-IED National Center of Excellence.
On 1 January 2013, the Support Command of the Land Operational Forces was suppressed. Consequently, the Engineers Command passed directly under the Land Operational Forces Command. On 1 October 2016, the Engineers Command passed under the command of the newly established Operational Land Forces Support Command, with a simultaneous reduction in rank from division to brigade.
On 1 July 2020, the Engineer Command was reorganized. The Command was raised again to Divisional Command, with two new Brigade-level units:
Engineer Brigade, with training and operational tasks;
Infrastructure Command, for the execution of public works related to the Army.
Mission
The Engineers Command has the task of:
Prepare the necessary assets to support the maneuvering forces in operations;
Ensuring the execution of emergency interventions in favor of populations affected by events of public disasters.
Carry out specialty training activities and in the EOD and/or IEDD and Force Protection sectors.
Provide for the development of the employment and technical doctrine, as well as for the development of studies.
Ensure the efficiency of the infrastructural park used by the Italian Army.
Provide the address for the qualification, specialization, updating, professionalization and employment of the personnel of the Arm of Engineer and the Corps of Engineers (infrastructure specialty).
Structure
With the 2020 reorganization, the Engineer Command oversees two one-star rank commands, the Engineer Brigade and the Infrastructure Command.
Commander, Engineer Command
Deputy Commander
Chief of Staff
Personnel Office
Doctrine, Studies and Lessons Learned Office
Operation, Training and Information Office
C4 Office
COBAR
Military chaplain
Engineer Command, in Cecchignola (Lazio)
Engineer Brigade, in Cecchignola (Lazio)
2nd Pontieri Engineer Regiment, in Piacenza (Emilia-Romagna)
6th Pioneer Regiment, in Rome-Cecchignola (Lazio)
"Nemi" Battalion, in Rome-Cecchignola
"Trasimeno" Battalion, in Rome-Cecchignola
Ferrovieri Engineer Regiment, in Castel Maggiore (Emilia-Romagna)
Counter-IED Center of Excellence, in Cecchignola (Lazio)
Force Protection Engineers Support Center, in Cecchignola (Lazio)
Training Battalion, in Cecchignola (Lazio)
Infrastructure Command, in Cecchignola (Lazio)
1st Infrastructure Department, in Turin (Piedmont)
3rd Infrastructure Department, in Milan (Lombardy)
4th Infrastructure Department, in Bolzano (South Tyrol)
Operational Infrastructure Engineer Unit, in Cecchignola (Lazio)
Historical and Cultural Institute of the Arm of Engineer
See also
Structure of the Italian Army
Notes and references
Commands of the Italian Army (post-1946)
Army units and formations of Italy
Military units and formations established in 2010
Military engineering by country | Engineer Command (Italy) | [
"Engineering"
] | 1,279 | [
"Military engineering by country",
"Military engineering"
] |
62,507,181 | https://en.wikipedia.org/wiki/TectoRNA | TectoRNAs are modular RNA units able to self-assemble into larger nanostructures in a programmable fashion. They are generated by rational design through an approach called RNA architectonics, which make use of RNA structural modules identified in natural (or sometimes artificial) RNA molecules to form pre-defined 3D structures spontaneously.
The abilities of RNA which is capable of catalysis and non-canonical base pairing make it an attractive biomolecule for design. By applying the knowledge of computational modeling and biochemical characterization, RNA can be shaped into defined geometries and conduct various functions. As such, tectoRNA can also carry functions to build large functional nanostructures which can be used for synthetic biology and nanotechnology application.
Overview
Nadrian Seeman was the first one who proposed that DNA could be used as material for generating nanoscopic self-assembling structures. This concept was extended to RNA by Jaeger and collaborators in 2000 by taking advantage of the concept of RNA tectonics initially proposed by Jaeger and Westhof and collaborators in 1996.
To design a tectoRNA, the deep knowledge of RNA tertiary structure is required. The rational design of tectoRNA is based on known X-ray and NMR structures. TectoRNAs can be seen as analogous to words, and, by using the natural syntax of RNA structural motifs, all kinds of thermodynamically stable shapes can be rationally designed and synthesized. The sequence specifying for stable, recurrent, and modular structural motifs, e.g. GNRA tetraloop, kissing loops, kink turns, A-minor interaction, etc., can be encoded within tectoRNAs to control their geometry and self-assembly into nanostructures. However, tectoRNA can also incorporate flexible junctions and RNA modules (or RNA aptamers) responsive to ligands.
Nowadays, extensive databases and powerful algorithms can be useful tools to design sequences of tectoRNAs. The folding of tectoRNAs are optimized by minimizing the free energy and maximizing their thermodynamic stability. The RNA sequences are mainly transcribed in vitro, and the folding condition for RNA is also important. Mg2+ and other salts must be added into solution and the concentration is well controlled to fold RNA properly. Their expected folding and self-assembly properties are characterized by a wide range of biochemical tools. Native poly-acrylamide gel electrophoresis (PAGE) is used to test the Kd of self-assembled tectoRNAs. Temperature gradient gel electrophoresis (TGGE) is applied to characterize the thermodynamic stability of nanostructures. Chemical probing, like DMS probing, allows us to indirectly understand the folding of RNA structure. Atomic force microscopy (AFM), transmission electron microscopy (TEM), and cryo-EM are powerful techniques which give us a direct clue how RNA nanostructures look like. By far, delicate structures like squares or hearts have been successfully demonstrated in different research.
RNA architectonics or RNA modular origami
TectoRNAs are the basic self-assembling unit in RNA architectonics. In RNA architectonics, the sequence length of tectoRNA is usually less than 200 nts. TectoRNAs are typically originating from single stranded RNA molecules and once folded, they act like LEGO bricks to build up higher order architectures. They can be synthesized, folded and self-assembled into multimeric nanostructures during transcription in isothermal conditions. As such, the RNA architectonics approach can be seen as RNA modular origami. This approach was extended to the synthesis of larger self-assembling units of more than 400 nts. More recently, RNA origami was extended to the design of long single stranded RNA sequences able to fold into large pre-defined nanostructures. Hence, RNA modular origami (originally called RNA architectonics), RNA origami and RNA single stranded origami are both originating from the same concept where RNA sequences can be design to self-fold and assemble into predefined shapes. Note that conceptually, DNA single stranded origami is more related to RNA origami than DNA origami.
Applications
Though RNA nanotechnology is still a burgeoning field, tectoRNAs and resulting nanostructures have already been shown to be useful in nanomedicine, nanotechnology, and synthetic biology. This includes the development of programmable nano-scaffolds and nano-particles for the delivery of RNA therapeutics. As such, RNA nanoparticles, like hexagonal nanorings, can be used as a delivery vehicle carrying therapeutic RNA to targeting cells. It is also possible to incorporate modified nucleotides within tectoRNAs in order to increase their chemical stability and resistant towards degradation. Yet, the full potential of tectoRNAs and resulting nanostructures for recruiting proteins and ligands still remain largely unexplored.
See also
DNA nanotechnology
DNA origami
RNA origami
References
RNA
Nanotechnology | TectoRNA | [
"Materials_science",
"Engineering"
] | 1,060 | [
"Nanotechnology",
"Materials science"
] |
62,510,434 | https://en.wikipedia.org/wiki/GUIDE-Seq | GUIDE-Seq (Genome-wide, Unbiased Identification of DSBs Enabled by Sequencing) is a molecular biology technique that allows for the unbiased in vitro detection of off-target genome editing events in DNA caused by CRISPR/Cas9 as well as other RNA-guided nucleases in living cells. Similar to LAM-PCR, it employs multiple PCRs to amplify regions of interest that contain a specific insert that preferentially integrates into double-stranded breaks. As gene therapy is an emerging field, GUIDE-Seq has gained traction as a cheap method to detect the off-target effects of potential therapeutics without needing whole genome sequencing.
Principles
Conceived to work in concert with next-gen sequencing platforms such as Illumina dye sequencing, GUIDE-Seq relies on the integration of a blunt, double-stranded oligodeoxynucleotide (dsODN) that has been phosphothioated on two of the phosphate linkages on the 5' end of both strands. The dsODN cassette integrates into any site in the genome that contains a double-stranded break (DSB). This means that along with the target and off-target sites that may exist as a result of the activity of a nuclease, the dsODN cassette will also integrate into any spurious sites in the genome that have a DSB. This makes it critical to have a dsODN only condition that controls for errant and naturally occurring DSBs, and is required to use the GUIDE-seq bioinformatic pipeline.
After integration of the dsODN cassette, genomic DNA (gDNA) is extracted from the cell culture and sheared to 500bp fragments via sonication. The resulting sheared gDNA undergoes end-repair and adapter ligation. From here, DNA specifically containing the dsODN insert is amplified via two rounds of polymerase chain reaction (PCR) that proceeds in a unidirectional manner starting from the primers that are complementary to the dsODN. This process allows for the reading of the adjacent sequences, both the sense and anti-sense strands, flanking the insert. The final product is a panoply of amplicons, describing the DSB distribution, containing indices for sample differentiation, p5 and p7 Illumina flow-cell adapters, and the sequences flanking the dsODN cassette.
GUIDE-Seq is able to achieve detection of rare DSBs that occur with a 0.1% frequency, however this may be as a result of the limitations of next-generation sequencing platforms. The greater the depth of reads an instrument is able to achieve, the better it can detect rarer events. Additionally, GUIDE-Seq is able to detect sites not predicted by the "in silico" methods which often will predict sites based on sequence similarity and percent mismatch. There have been cases of GUIDE-Seq not detecting any off-targets for certain guide RNAs, suggesting that some RNA-guided nucleases may have no associated off-targets. GUIDE-Seq has been used to show that engineered variants of Cas9 can have reduced off-target effects.
Caveats
GUIDE-Seq has been shown to miss some off-targets, when compared to the genome-wide sequencing DIGENOME-Seq method, due to the nature of its targeting. Another caveat is that GUIDE-Seq has been observed to generate slightly different off-target sites depending on the cell line. This could be due to cell lines having different parental genetic origins, cell line specific mutations, or, in the case of some immortal cell lines such as K562s, having aneuploidy. This suggests that it would be pertinent for researchers to test multiple cell lines to validate efficacy and accuracy. GUIDE-Seq cannot be used to identify off-targets in vivo.
References
Genome editing
Molecular biology | GUIDE-Seq | [
"Chemistry",
"Engineering",
"Biology"
] | 810 | [
"Genetics techniques",
"Genome editing",
"Genetic engineering",
"Molecular biology",
"Biochemistry"
] |
62,510,740 | https://en.wikipedia.org/wiki/Fuxianospira%20gyrata | Fuxianospira gyrata is a Cambrian macroalgae found in the Chengjiang lagerstätte. Preserved in clustered, helicoid groups, the filaments are threadlike, plain and without branches. Brown and smooth in appearance, these structural characteristics display a resemblance to modern brown algae. A limited amount of algae species have been discovered in the Chengjiang biota, suggesting that diversity within the general algae population may have been sparse. It is thought that the macroalgae could be the most basic component of the Chengjiang biota food chain.
It is also theorised that Fuxianospira gyrata, among other Chengjiang algae, is actually a coprolite.
See also
List of Chengjiang Biota species by phylum
References
Heterokonts
Cambrian species | Fuxianospira gyrata | [
"Biology"
] | 168 | [
"Heterokonts",
"Eukaryotes",
"Eukaryote stubs",
"Algae"
] |
62,512,841 | https://en.wikipedia.org/wiki/Maritime%20industries%20of%20Taiwan | The maritime industries of Taiwan are a large part of Taiwan's economy. Industries of particular importance are shipbuilding, boat building, maritime transport, aquaculture, mariculture, commercial fishing, seafood processing, offshore wind power and various forms of tourism. Deep sea mining, especially of dormant hydrothermal vents, is also being considered for the future. In 2018 Taiwan was the fourth largest yacht building nation. Taiwan is home to a number of maritime museums and maritime colleges.
Background
Taiwan is an island nation and as such has an intimate relationship with the sea. Seafarers from Taiwan are believed to have colonized the Ryukyu Islands 30,000 year ago. The indigenous Yami people of Orchid Island are famous for their seafaring skills and most Taiwanese indigenous people practiced some right or ritual related to the sea. Waves of immigrants and conquerors have traveled to Taiwan over the seas from Mainland China, Europe, Japan, and elsewhere. The people of Taiwan are collectively known as the "Children of the Sea.”
The principle goddess of chinese folk religion as practiced in Taiwan is the sea goddess Mazu. Her veneration is particularly popular along Taiwan's east coast.
Geographically Taiwan's relationship with the sea is shaped by its location at the eastern end of the Eurasian landmass. The east coast is under the influence of the strong Kuroshio Current. The west coast of Taiwan is muddy with large tidal flats, tides in the west are much stronger than those on the east and as such they have a much greater influence on daily routines.
The Ship and Ocean Industries R&D Center (SOIC), founded in 1976 as the United Ship Design and Development Center (USDDC), plays an important role in supporting Taiwan's maritime industries. SOIC works on commercial, government, and military projects as well as basic scientific research. The Yacht Industry Department of SOIC is the only government supported R&D center for yacht materials and design in the world.
Taiwan's maritime culture suffered under the KMT who nationalized the seashore and closed off access to most Taiwanese as well as forbade private recreational boat ownership. This led to an extreme disconnect between the island nation and the waters which surround it. As late as 2010 half of all Taiwanese did not know how to swim. Since the end of the martial law period the Taiwanese people have embarked on a process of re-embracing their maritime culture.
Sea transport
As of 2009 90% of Taiwan's trade was seaborne. Evergreen Marine and Yang Ming Marine Transport Corporation are two major ocean shipping companies based in Taiwan. Wan Hai Lines and Today Makes Tomorrow are smaller but still globally significant ocean shipping companies. In 2016 amid a global downturn in the shipping industry the Taiwanese government spent $1.9B to support the domestic shipping industry.
As of 2019 Taiwan had the 11th largest national shipping capacity by deadweight tons.
Ports
Taiwan's main ports are located in Taipei, Keelung, and Kaohsiung. Most of the nation's large ports are managed by Taiwan International Ports Corporation which is a state-owned enterprise.
Shipbuilding
The modern shipbuilding industry of Taiwan began in 1948 when the Government established the Taiwan Shipbuilding Corporation (TSBC) in Keelung. In 1957 the US based Ingalls Shipbuilding Corporation established the Ingalls Taiwan Shipbuilding and Drydock Company, which subsequently rented the TSBC shipyard and produced 14 vessels between 1957 and 1962. The Government prioritized shipbuilding as one of the core industries of the economy, in 1973 they established the China Shipbuilding Corporation which was merged with TSBC in 1978. In 2008 the ship- and boat-building industry had a production value of 2.09b USD with CSBC accounting for 54% of production, small and medium yards 22% and yacht builders 16%.
As of 2009 there were 116 shipyards (including 34 yacht builders) and 10 marine equipment companies in Taiwan. Major shipyards include CSBC Corporation, Taiwan, Jong Shyn Shipbuilding Company, and Lungteh Shipbuilding. Military and Coast Guard orders make up a large portion of shipbuilders books by dollar value. Between the Taiwanese Navy and the Coast Guard Administration Taiwan spends approximately a billion dollars a year on new vessel construction.
Yacht building
One third of new yachts sold in the US between 1977 and 1981 were made in Taiwan. In 1987 Taiwan exported 1,755 vessels worth US$190.8 million to the US. During this era more than 100 shipyards and boatbuilders in Taiwan built craft for the export market. Between 1986 and 1992 the New Taiwan Dollar appreciated 58% against the US Dollar which made Taiwanese built yachts significantly less competitive in the US market. By 1994 dozens of yacht and boat builders had gone out of business or been acquired by competitors. Sales recovered but fell again after the 2008 Recession before strengthening again.
In 2017 Taiwan exported one hundred and sixty two yachts. In 2018 Taiwan was the fourth largest yacht building nation by feet of yacht built after Italy, The Netherlands and Turkey. Major yacht and boat builders include Horizon Yachts, Ocean Alexander, Johnson Yachts, Jade Yachts, and Ta Shing Yacht Building. Taiwan remained fourth in the world through 2021.
Maritime recreation
Regulations enacted during the martial law era meant that ownership of personal leisure craft was not permitted until 2010. While maritime recreation facilities and infrastructure remain underdeveloped the Taiwanese government has emphasized marine sports and related tourism as an economic opportunity for Taiwan's outlying islands.
The development of Taiwan's domestic yachting industry has been led by its domestic yacht manufacturers with Kha Shing and Horizon building marinas with associated repair/refit facilities.
Aquaculture
Aquaculture has a long history in Taiwan. By 2006 the production of Taiwanese coastal aquaculture was valued at NT$11,817 million. In the 21st century high technology is playing a greater part in Taiwan's aquaculture industry as the industry struggles to cope with labor shortages and fierce foreign competition. The Taiwanese government operates six fisheries and aquaculture research centers.
The Aquaculture Taiwan Expo & Forum is the primary aquaculture trade show in Taiwan, it is held concurrently with the Livestock Taiwan Expo & Forum and the Asia Agri-Tech Expo & Forum.
The Taiwanese scientist Liao I-chiu is known as the "Father of Shrimp Farming,” having pioneered many of the techniques and overcome many of the technical hurdles which allowed the creation of the modern global shrimp farming industry. The giant river prawn is widely cultivated in Taiwan. In 2012 Taiwan produced 3% of world production.
Milkfish is one of Taiwan's most commercially important fish, yearly production is 50,000 tons of milkfish valued at $4.1 billion New Taiwan Dollars. Consumption and ranching of milkfish in Taiwan dates back hundreds of years.
The Taiwanese ornamental fish and shrimp industry is significant with more than 250 commercial operations, ~200 of them with operations in Pingtung County. Taiwan was once known as the “cichlid kingdom” for its specialization in cichlids, a fad which culminated in the breeding of the blood parrot cichlid in 1986. The fields of biotechnology and applied ecology are playing an ever increasing role in the Taiwanese aquarium sector.
Fisheries
Taiwan is one of the largest fishing nations on earth and the associated fish processing industry is also significant. More than one third of the worlds longline tuna fishing vessels are operated by Taiwanese companies with the total strength of the distant waters fishing fleet at more than 2,000 vessels. The fishing industry is estimated to be worth approximately two billion dollars. Taiwan's ocean fisheries sector employs 350,000 people and there are 130,000 fishing households in Taiwan. The Taiwanese seafood industry was worth 1.3 billion dollars a year in 2020.
Taiwanese conglomerate FCF Co, Ltd. is one of the largest tuna trader in the world moving more than half million tons a year, in 2019 they acquired Bumble Bee Foods for close to 1 billion dollars.
Taiwan cooperates with the United States to reduce illegal, unreported and unregulated fishing (IUU).
Inshore and nearshore fishing
Bottom trawlers with a tonnage under 50 are restricted from trawling within 5km of shore and those over 50 tons are restricted from trawling within 12km of shore. Bottom trawling is controversial in Taiwan due to the environmental damage it causes.
Distant-water fishing
Taiwan has the world's second largest distant-water fishing fleet with 1,100 vessels Taiwan flagged or directly owned vessels that employ 35,000 migrant sailors primarily from Indonesia and the Philippines. The Taiwanese government heavily subsidizes the distant waters fishing industry.
Taiwan's overseas fishing fleet has been criticized for a history of abuse and a lack of protection for migrant laborers, often from Southeast Asia. Official Taiwanese sources put the number of foreign workers aboard Taiwanese vessels at 26,000 but NGOs and US government agencies put the figure around 160,000. Foreign fishermen frequently report non-payment, long work hours, and verbal and physical abuse at the hands of their captains and officers, who are often Taiwanese. In recent years Taiwan has made significant progress on the issue, but abuse remains widespread. In terms of human rights the distant waters fishing fleet lags far behind the rest of Taiwanese industry.
A 2020 Greenpeace investigation found Taiwanese vessels in the Atlantic Ocean engaged in illegal, unreported and unregulated fishing. They also found significant evidence of the abuse of foreign laborers. They also documented Taiwanese fishing companies using flags of convenience to obscure vessel ownership as well as unreported at sea transfers of fish. Taiwanese fisheries conglomerate FCF was specifically singled out for criticism for links to illegal fishing and forced labor.
In October 2020 the US Department of Labor added the Taiwanese distant waters fleet's products to its list of goods produced by child or forced labor. In May 2021 the Control Yuan ordered the Ministry of Foreign Affairs, the Ministry of Labor, and the Fisheries Agency to address the issue and heavily criticized their lack of action.
In 2022 nine Taiwanese were indicted for the abuse of migrant laborers on distant waters fishing vessels. In April 2022 the minimum wage for laborers aboard Taiwanese distant waters fishing vessels was raised in addition to new requirements being put in place concerning direct payment of wages and provision of health insurance. The wage increase was implemented in July.
Approximately ninety Taiwanese vessels participate in the long distance North Pacific saury fishery. Taiwan's total saury landings were 30k metric tons in 2021 and 40k metric tons in 2022.
Boats in the saury and squid fisheries have been transitioning from incandescent and high-intensity discharge (HID) light bulbs to light emitting diodes (LED) which allows them for an environmental impact reduction.
Offshore wind power
The first offshore wind farms in Taiwan, Formosa 1 Offshore Wind Farm, started its commercial operation in April 2017 at off the coast of Miaoli County. The Formosa II wind farms will be constructed also offshore Miaoli County with a planned capacity of 300-500 MW. The Formosa III wind farm will be constructed offshore Changhua County with a planned capacity of 1,900 MW. Taiwan has one of the fastest growing offshore wind power industries in the world. As of 2020, there were 361 onshore turbines and 22 offshore turbines in operation with the total installed capacity of 845.2 MW.
Maritime museums
Evergreen Maritime Museum
Ocean Resources Museum
Tamkang University Maritime Museum
YM Museum of Marine Exploration Kaohsiung
YM Oceanic Culture and Art Museum
National Museum of Natural Science
Maritime education
In 2007 the Ministry of Education released the Marine Education Policy, the first education policy document with a maritime focus. As of 2014 marine and maritime education at the primary and secondary level had been greatly expanded with each of Taiwan's 22 counties, special municipalities and cities establishing a marine education center at either an elementary or high school. Within nationwide science curriculums the portion of marine centered content has been increased. Marine issues are also taught to 9th graders nationwide as part of a curriculum on oceans and climate change.
Maritime colleges
National Taiwan Ocean University
Taipei University of Marine Technology
See also
Maritime and Port Bureau
Ocean Affairs Council
Taiwan Ocean Research Institute
Sinking of Chian-der 3
Defense industry of Taiwan
References
Industry in Taiwan
Maritime history of Taiwan
Military history of Taiwan
Maritime culture in Asia
Science and technology in Taiwan
Shipbuilding
Fishing industry in Taiwan
Boating
Illegal, unreported and unregulated fishing | Maritime industries of Taiwan | [
"Engineering"
] | 2,501 | [
"Shipbuilding",
"Marine engineering"
] |
62,516,519 | https://en.wikipedia.org/wiki/YouTube%20Rewind%202019%3A%20For%20the%20Record | YouTube Rewind 2019: For the Record (also known simply as YouTube Rewind 2019) is a video that was uploaded to YouTube's official channel on the video-sharing website YouTube on December 5, 2019, as the tenth and final installment of the YouTube Rewind series. The video contains montages of the top videos and YouTubers of the year.
Although marked as an improvement over the previous installment, YouTube Rewind 2018: Everyone Controls Rewind, the video received negative reviews, with critics and the general audience finding the video uncreative in comparison to past Rewind videos.
For the Record amassed over 3.1 million dislikes within 24 hours of release and 5 million dislikes within 48 hours of release, more than those acquired by Everyone Controls Rewind in the same timeframes. It currently has over 9.6 million dislikes, making it the sixth most-disliked video on YouTube. YouTube forwent producing a Rewind installment for 2020, and announced the series' discontinuation the following year.
Overview
The video begins with a 'rewind' of 2019's most viewed/liked videos on YouTube. It then cuts to a scene from YouTube Rewind 2018: Everyone Controls Rewind where Casey Neistat and the Merrell Twins suggest K-pop as one of the themes for the rewind. Following this, it cuts to multiple YouTubers' reactions to this scene where it has been labelled as awkward and YouTube themselves stating that "In 2018, we made something you didn't like. So in 2019, let's see what you DID like. Because you're better at this than we are", with the words on screen. A compilation of trending YouTube videos from 2019 is shown, then cuts to the words on screen, saying "You made these the MOST LIKED CREATOR VIDEOS of 2019, duh...", in the form of a 'top 10' list, with a short snippet of each video playing at their appropriate times.
The video then proceeds to show the "Most Liked Music Videos", again in the form of a 'top 10' list with a short snippet of each video playing at their appropriate times.
The video then proceeds to show the "Most Liked Dance Videos" in the form of a 'top 5' list with a short snippet of each video playing at their appropriate times.
The video proceeds to show the "Most Viewed Video Games" in the form of a 'top 5' list with a short snippet of game-play at their appropriate times.
The video proceeds to show the "Most Liked Beauty Videos" in the form of a 'top 5' list with a short snippet of each video at their appropriate times.
The video cuts to another tape 'rewind' with the words on-screen: "You helped these New Creators Break Out", then proceeds to show YouTube channels with the most subscribers which first uploaded in 2019 in the form of a 'top 10' list with a short snippet of videos from each creator at their appropriate times.
The video cuts to another tape rewind, with the words on-screen: "You made these the Most Watched Creators", then proceeds to show the most viewed creators of 2019 in the form of a 'top 10' list with short snippets of videos from each creator at their appropriate times.
The video cuts to the words onscreen: "You liked, disliked, watched, subscribed, commented, shared, uploaded, played, listened, saved, created. Thank you for a record breaking 2019." It then proceeds to show multiple channels and their achievements in 2019 with appropriate videos.
It then cuts to a short time-lapsed compilation of 2019's trending videos being 'sucked' into the middle. The video ends with a shot from Lil Dicky's music video of his song "Earth".
Production
The 2019 edition returned to a format more reminiscent of the 2010 and 2011 iterations of the series, featuring a montage of the top videos of 2019, divided into several themed countdowns based on statistics and trends. Kevin Allocca, YouTube's head of culture and trends, explained that the video was intended to be more reflective of the year's trends, acknowledging that it was becoming more difficult for the previous format, which ran from 2012 to 2018, to "authentically represent" the community's overall experience.
Cast
Below is a list of channels featured in the top lists in YouTube Rewind 2019, derived from the video's description:
1MILLION Dance Studio
A4
Anaysa
Andymation
Ariana Grande
Awez Darbar
Aya Nakamura
Azzyland
Badabun
Billie Eilish
Black Gryph0n
Blackpink
BTS
ChapkisDanceUSA
Daddy Yankee
David Dobrik
Dude Perfect
F2Freestylers
Felipe Neto
Fischer's- フィッシャーズ
Galen Hooks
HYBE LABELS
James Charles
Jeffree Star
Jelly
Kaykai Salaider
Kurzgesagt – In a Nutshell
Kylie Jenner
Lazarbeam
Lil Dicky
Lil Nas X
LOUD
LOUD Babi
LOUD Coringa
Magnet World
MrBeast
Nilson Izaias Papinho Oficial
Noah Schnapp
Noor Stars
백종원의 요리비책 Paik's Cuisine
Pencilmation
PewDiePie
Rosalia
Seth Everman
Shane Dawson
Shawn Mendes
Team Naach
T-Series
whinderssonnunes
워크맨-Workman
하루한끼 one meal a day
Below is a list of channels whose footage was included in YouTube Rewind 2019, but were not featured in the top lists of YouTube Rewind 2019:
Angie Velasco
Atta Halilintar
Badabun
Big Marvel
Blanco Brown
Brooklyn and Bailey
Casey Neistat
Connor Franta
Emma Chamberlain
Free Fire - Brasil
GamingWithKev
Garena Free Fire Indonesia
h3h3Productions
Hongyu ASMR 홍유
HunniBee ASMR
IAMLXGEND
ItsFunneh
Jenna Marbles
Jennelle Eliana
Lachlan
mrfreshasian
NikkieTutorials
PlayHard
RiceGum
ROSALÍA
Shoaib Akhtar
Sidemen
Simone Giertz
SQUEEZIE
Suzy Lu
Tati
The Try Guys
TheDonato
Pac-12 Networks
VEGETTA777
Soundtrack
YouTube Rewind 2019 contains the following songs (timestamps in brackets refer to when the song appears in the Rewind video):
"7 Rings" by Ariana Grande (0:22–1:34)
"Tokyo Drifting" by Glass Animals and Denzel Curry (1:35–2:27)
"Bad Guy" by Billie Eilish (2:29–3:15)
"Don't Start Now" by Dua Lipa (3:17–5:23)
Reception
Despite being seen as an improvement over the previous year's Everyone Controls Rewind, For the Record received negative reviews, with many viewers disappointed that it did not have the same level of production as previous installments in the series, and noting it as being akin to WatchMojo videos. Many also felt the new format lacked "ambition, energy and a soul", and that it showed that YouTube was being openly more corporate and uncaring towards their creators. Others have also noted the omission of PewDiePie's "Congratulations" from the list of most liked music videos of the year, despite YouTube's listing standards which prevent geo-restricted content from being included in For the Record. Another PewDiePie-related criticism was how none of his accomplishments were included in the "YouTubers' Achievements in 2019" segment, yet it included T-Series (the first channel to hit 100 million subscribers, despite PewDiePie becoming the first creator to do so) and Enes Batur (a creator from Turkey who came under fire for copying PewDiePie, and abusing the copyright system against fellow creator JT after he called Batur out on said copying.) Similarly to last year, some viewers criticized the video for its complete lack of tributes to YouTubers that had died before December, such as Desmond "Etika" Amofah. However, viewers saw improvement with casting choices in some areas, particularly with the inclusion of PewDiePie, who was absent in the last two installments. For the Record won the 2020 Webby Award for Entertainment in the category Web.
Despite being included in the video, PewDiePie, along with FlyingKitty, Party In Backyard, Grandayy and Dolan Dark, created their take of it on December 29, 2019, titled "YouTube Rewind 2019, but it's actually good", which focused on the notable memes of 2019 and also paid homage to various recently deceased creators, including Dillon the Hacker, Etika and Grant Thompson.
, For the Record currently has over 117 million views and over 9.5 million dislikes, making it the sixth most-disliked YouTube video and the third most-disliked non-music YouTube video of all time after Everyone Controls Rewind and the trailer for Sadak 2. It was peaked as the third most-disliked video at the time before being surpassed by the Sadak 2 trailer within three days.
See also
List of most-disliked YouTube videos
References
External links
The creators, music and moments as featured in REWIND 2019 (playlist)
2010s YouTube controversies
2019 controversies
2019 YouTube events
2019 YouTube videos
Internet memes introduced from the United States
Viral videos
Works about video games | YouTube Rewind 2019: For the Record | [
"Technology"
] | 1,954 | [
"Works about video games",
"Works about computing"
] |
62,516,934 | https://en.wikipedia.org/wiki/Robert%20Guillaumont | Robert Guillaumont (born 26 February 1933 in Lyon) is a French chemist and honorary professor at the University of Paris-Saclay in Orsay (1967-1998), Member of the French Academy of Sciences and the French Academy of Technologies
Career
Robert Guillaumont is a specialist in radiochemistry and actinide chemistry. He prepared his doctorate at the Institut radium de Paris, Curie Laboratory, University of Paris VI (1966). He continued his research in this Institute and then at the Radiochemistry Laboratory of the Orsay (1968–98), which he directed for twelve years (1979–90). He taught chemistry/radiochemistry at the University of Paris XI-Orsay (1967–98). His expertise covers the chemistry of the nuclear fuel cycle (from uranium mining to waste management and spent fuel reprocessing) and nuclear energy issues. He has been a member or chairman of numerous French and international committees dealing with the nuclear fuel cycle, nuclear energy, radioactive waste management and the synthesis and use of radionuclides for medicine. He was a member of the National Commission for the Evaluation of Research on Nuclear Materials and Radioactive Waste (1994-2019).
Research
Robert Guillaumont began his research in 1959 on the chemistry of protactinium in solution. He showed that the electronic filling of the 5f underlay begins for this element. The UV absorption spectrum of Pa4+ is typical of a 5f16d1 transition (Pa atom: 5f26d17s2). Together with his collaborators, he extended his methodology for studying the behaviour of radioelements in imponderable quantities to other actinides. The rest of his work can be linked to the common thread of the consequences of filling the atomic underlayer 5f on the physicochemical properties of actinides. This filling plays an essential role in the behaviour of the 15 actinides, especially when these electrons are delocalized, from protactinium (Pa) to americium (Am). This results in a high richness of oxidation degrees of the first actinides (usually from 3 to 6) and in the manifestation of particular effects in the series (electronic states characterized by the quantum number J). Thus, he studied the thermodynamic consequences of the population of sublayer 5f on a series of solution complexes (citric complexes of trivalent actinides from Am to fermium (Fm). He showed the existence of the "tetrad effect" for trivalent actinide complexes, an effect that reflects an extra-stabilization of the fundamental state of actinides for 1/4, 1/2 and 3/4 of the filling of the 5f underlay. After the curium (Cm), it is necessary, to carry out experiments, to synthesize isotopes of berkelium (Bk), einstenium (Es) and Fm by nuclear reactions with particle accelerators, and separate them from irradiated targets, which he did at Orsay. To conduct most of his research he developed the methodology for studying species and equilibria between species in extremely diluted solutions (which radioactivity allows until about 10−14 M), and he pushed, at the theoretical level, the description of the thermodynamic behaviour of a few atoms in terms of deviation from the law of mass action, which gave a foundation to chemical experiments on elements 6d (Z>103), produced atom by atom by radiochemists at accelerators.
At the same time, he participated in the study of thermodynamic and spectroscopic properties of elements 5f (and 4f) in connection with electronic transfers between these elements and their environment: covalence in two-phase solvent extraction systems and crystal field effect on solids, in particular single crystals examined at 4 K.
Finally, he continued his research on the fundamental problems of radionuclide migration in the environment (speciation, concentration effect, retention on colloids) and selective separation of actinides/lanthanides from the elements constituting spent nuclear fuel. R. Guillaumont's research themes are upstream of the many chemistry/radiochemistry problems encountered in "nuclear": chemistry of actinides from uranium to curium in the various stages of nuclear fuel cycles and radioactive waste management.
He has published more than 200 scientific articles, popular articles and has written several books.
Honours and awards
Chevalier of the Ordre national de la Légion d'Honneur
Chevalier of the Ordre National du Mérite
Officier of the Ordre des Palmes Académiques
References
1933 births
Scientists from Lyon
20th-century French chemists
Radiochemistry
Living people
Members of the French Academy of Sciences
21st-century French chemists
Pierre and Marie Curie University alumni
Academic staff of Paris-Saclay University | Robert Guillaumont | [
"Chemistry"
] | 1,005 | [
"Radiochemistry",
"Radioactivity"
] |
62,518,551 | https://en.wikipedia.org/wiki/TerminusDB | TerminusDB is an open source knowledge graph and document store. It is used to build versioned data products. It is a native revision control database that is architecturally similar to Git. It is listed on DB-Engines.
TerminusDB provides a document API for building via the JSON exchange format. It implements both GraphQL and a datalog variant called WOQL. TerminusCMS is a cloud self-serve content and data platform built on TerminusDB.
TerminusDB is available under the Apache 2.0 license. TerminusDB is implemented in Prolog and Rust.
History
TerminusDB, previously known as DataChemist, was founded in Dublin, Ireland. Starting in Trinity College Dublin, the development team behind TerminusDB ran the Horizon 2020 project ALIGNED that worked from February 2015 to January 2018. An open-access e-book entitled Engineering Agile Big-Data Systems was published on completion of the ALIGNED project.
Version 1.0 was released in October 2019. TerminusDB was first released under the GPLv3 license with the client libraries released with the Apache 2 license. With v4.0, which was released in December 2020, TerminusDB switched to the Apache 2.0 license. The shift was discussed extensively.
Release history
Name
TerminusDB is named after the Roman God of Boundaries, Terminus. It is also named after the home planet of the Foundation in the series of science-fiction novel by Issac Asimov. TerminusDB uses a CowDuck mascot - the motif finds its origins in the examples used by core engineer Matthijs van Otterdijk when first demonstrating the append only immutable data store
Software design
TerminusDB is an in-memory graph database management system with a rich query language. The design of the underlying data structure, which is implemented in a Rust library, uses a succinct data structures and delta encoding approach drawing inspiration from software source control systems like Git. This allows all of the Git semantics to be used in TerminusDB.
Data model
TerminusDB is based on the RDF standard. This standard specifies finite labelled directed graphs which are parameterized in some universe of datatypes. The names for nodes and labels are drawn from a set of IRIs (Internationalized Resource Identifiers). TerminusDB uses the XSD datatypes as its universe of concrete values. For schema design, TerminusDB used the OWL language until version 10.0. Since version 10 it uses a JSON schema interface allowing users to build schemas using a simple JSON format. This provides a rich modelling language which enables constraints on the allowable shapes in the graph.
TerminusDB has a promise based client for the browser and node.js it is available through the npm registry, or can be directly included in web-sites. It also has a Python client for the TerminusDB RESTful API and a python version of the web object query language, WOQLpy.
Query language
GraphQL is implemented to allow users to query TerminusDB projects in such a way that deep linking can be discovered.
WOQL (web object query language) is a datalog-based query language. It allows TerminusDB to treat the database as a document store or a graph interchangeably, and provides query features to make relationship traversals easy. This gives a relatively straightforward human-readable format which can be easily stored in TerminusDB itself.
Example
A simple query which creates a document in the database, along with labels and cardinality constraints.
WOQL.doctype("BankAccount").label("Bank Account")
.property("owner","xsd:string")
.label("owner")
.cardinality(1)
.property("balance","xsd:nonNegativeInteger")
.label("owner")
.cardinality(1)
VectorLink
TerminusDB published a sidecar vector database called VectorLink. It is a data tool to provide large language models with semantic context about data. Drawing on the features of TerminusDB, it provides versioned indexing of data and content..
References
External links
Graph databases
Structured storage
Free database management systems
Software companies of Ireland
Free software programmed in Rust
Logic programming
2019 software
NoSQL
Software using the GNU General Public License
Software using the Apache license
Free software programmed in Prolog | TerminusDB | [
"Mathematics"
] | 883 | [
"Graph databases",
"Mathematical relations",
"Graph theory"
] |
62,519,431 | https://en.wikipedia.org/wiki/Chaetomium%20perlucidum | Chaetomium perlucidum is a neurotropic dematiaceous (melanated cell wall) fungus that is naturally found in the soil, including in agricultural soil, and in the stems of dead plants. The fungus can also be found on the feathers of birds, manure, seeds, and even paper. It is able to thrive at temperatures of .
The fungus is an invasive opportunist to humans that can cause diseases such as onychomycosis (fungus on nails), otolaryngologic (head and neck) or respiratory inflammations (like sinusitis, pneumonia, and empyema), and brain necrosis.
History
It was first formally recorded in 1956 in Ukraine by K. S. Sergeeva.
Morphology
Chaetomium perlucidum is pigmented and dark in colour, appearing hairy and wooly, with a growth rate of 4-5 mm/day.
Perithecia (fruiting body)
Chaetomium perlucidum's fruiting bodies become fully mature in 13-16 days. The fruiting body's structural width is 90-200 μm, with an ostiolar pore (open pore) width of 30-50 μm.
Setae (bristle / "hair" structures)
Setae width is 2-3 μm and can have lengths of up to 700 μm. The setae are unbranched and appear to undulate.
Mature ascospores
Fully mature ascospores are 12.5-14 μm x 6-7.5 μm in size. They are smooth, oval-shaped, and brown in colour.
Lipid / fatty acid composition
Chaetomium perlucidum is composed of saturated, monounsaturated, and polyunsaturated fatty acids.
Pathogenicity
The fungus can cause chronic fungal infections in humans. An infection can spread throughout the body from a single point of infection into various other systems, e.g., the central nervous, cardiovascular, respiratory, and immune systems, with especially a low prognosis for cerebral infections.
Mode of transmission and infection
Infections take hold in the brain and progress to spread throughout the body. Pathways of entry into the host's body include via cutaneous lesions, oral intake, or intravenously.
Susceptibility
There have been at least two reported cases of cerebral phaeohyphomycosis in humans with one case resulting in death, reported in 2003. Both cases occurred in immunosuppressed individuals already suffering from complications of other unrelated diseases. Recreational drug users, or patients who have undergone intravenous or transplant procedures at even hospitals are also susceptible to being infected by C. perlucidum.
Treatment and prognosis
Most Chaetomium fungal diseases are without known cure and in one case of death from 1996, antifungal therapy through administering Amphotericin B (AMB) proved ineffective. AMB is a common and leading antibiotic treatment prescribed for fungal infections. In one case, C. perlucidum infection in the brain caused death from hemorrhaging throughout the body (especially in the brain) and complications that arose from acute inflammation. However, the physical removal of a C. perlucidum growth through a lobectomy (surgically removing the fungal growth from an area of affected organ/s) was successful in curing another patient from infection.
Culturing techniques
Chaetomium perlucidum ascospores can be cultured and grown in the lab through incubation on potato flake agar at 25°C for 6-10 days. Optimal growth temperature however is at 37°C. Mature perithecia can be obtained if the fungus has access to a sterile plant source.
Occurrence in farming soil
Chaetomium perlucidum was found more frequently in tilled than in untilled farmland.
References
perlucidum
Fungi described in 1956
Fungus species | Chaetomium perlucidum | [
"Biology"
] | 821 | [
"Fungi",
"Fungus species"
] |
63,402,706 | https://en.wikipedia.org/wiki/Pentaerythritol%20tetraacrylate | Pentaerythritol tetraacrylate (PETA, sometimes PETTA, PETRA) is an organic compound. It is a tetrafunctional acrylate ester used as a monomer in the manufacture of polymers. As it is a polymerizable acrylate monomer, it is nearly always supplied with an added polymerisation inhibitor, such as MEHQ (monomethyl ether hydroquinone).
Uses
PETA is part of a family of acrylates used in epoxy resin chemistry and ultraviolet cure of coatings. Similar monomers used are 1,6-hexanediol diacrylate and trimethylol propane triacrylate. It is a derivative of pentaerythritol
One of the key uses of the material is in polymeric synthesis where it can form micelles and block copolymers.
The molecule's acrylate group functionality enables the molecule to do the Michael reaction with amines. It is therefore sometimes used in epoxy chemistry enabling a large reduction in cure time. As the molecule has 4 functional acrylate groups it confers high cross-link density. Ethoxylation maybe used to produce ethoxylated versions which find use in electron beam curing. The material also has pharmaceutical uses
See also
1,6-Hexanediol diacrylate
Trimethylolpropane triacrylate
Acrylic acid
References
External links
Safety Data Sheet
Acrylate esters
Monomers | Pentaerythritol tetraacrylate | [
"Chemistry",
"Materials_science"
] | 312 | [
"Monomers",
"Polymer chemistry"
] |
63,402,933 | https://en.wikipedia.org/wiki/Diphasic%20sex%20expression | Diphasic sex expression (also known as labile sex expression or sex change), is defined as the alteration of the primary sex during the lifetime of an individual found within dioecious and subdioecious species. This change in sex expression is a response to environmental cues such as sun exposure and rainfall or drought levels. Labile sex expression is a type of diphasic sex expression that is found among many perennial plant species, and is defined as the switch from male to female once the plant has reached a certain size. In species with labile sex expression this change occurs only once, where as a plant expressing diphasic sex tendencies can switch from season to season.
Diphasic sex expression in plants
One well studied plant species with diphasic sex expression is Arisaema Triphyllum, commonly known as Jack-in-the-pulpit. It is hypothesized that diphasic plant species have higher fitness when expressing only one sex at a time when there are trade-offs between size and reproductive success through male and female function. Due to conflict between male and female function when pollen and ovules are produced in the same flower, one sex is ultimately favored over the other dependent on plant size. This sex trade-off is responsible for determining the population sex ratio, meaning the relative amount of male versus female individuals. If there are more males (typically smaller in size) than females (larger) for one season, then the males will have a lower reproductive contribution than females. However, considering their diphasic tendencies, male and female contribution should eventually reach equilibrium over time.
Diphasic sex expression in animals
Diphasic sex expression is not limited just to plants, as many species of fish also alter their sex. About two percent of known fish species display sequential hermaphroditic changes. For example, juvenile Caribbean parrot fish are female when young and may transition to male as they age. Many of these terminal phase males then go on to fulfill varying roles such as female and territorial protection.
List of known diphasic species
Arisaema drancontium
Arisaema japonica
Arisaema triphyllum
Ilex sp.
Ilec opaca
Humulus japonicus
Silene alba
Silene dioica
Silene otites
References
Cormier, Zoe. “Fish Are the Sex-Switching Masters of the Animal Kingdom.” Our Blue Planet, Our Blue Planet, 29 Nov. 2017, ourblueplanet.bbcearth.com/blog/?article=incredible-sex-changing-fish-from-blue-planet.
Cruzan, Mitchell B. Evolutionary Biology: A Plant Perspective. Oxford University Press., 2018.
Freeman, D. C., et al. “Sex Change in Plants: Old and New Observations and New Hypotheses.” Oecologia, vol. 47, no. 2, 1980, pp. 222–232., doi:10.1007/bf00346825.
Pavlowich, Tyler, et al. “Leveraging Sex Change in Parrotfish to Manage Fished Populations.” Elem Sci Anth, vol. 6, no. 1, 2018, p. 63., doi:10.1525/elementa.318.
Policansky, D. “Sex Choice and the Size Advantage Model in Jack-in-the-Pulpit (Arisaema Triphyllum).” Proceedings of the National Academy of Sciences, vol. 78, no. 2, 1981, pp. 1306–1308., doi:10.1073/pnas.78.2.1306.
“Research_Sex Ratio Evolution.” The Kalisz Lab, kaliszlab.weebly.com/sex-ratio-evolution.html.
Plant reproduction
Sex-determination systems | Diphasic sex expression | [
"Biology"
] | 778 | [
"Behavior",
"Plant reproduction",
"Plants",
"Sex",
"Sex-determination systems",
"Reproduction"
] |
63,404,263 | https://en.wikipedia.org/wiki/Lisa%20M.%20Porter | Lisa Marie Spellman Porter is an American materials scientist who is a Professor of Materials Science at Carnegie Mellon University. She works on new ways to process and characterise electronic materials. She has previously served as president of the American Vacuum Society.
Early life and education
Porter studied materials science at Cornell University. She earned her bachelor's degree in 1989, before moving to North Carolina State University for her graduate studies. She completed her doctorate on silicon carbide in 1993. After earning her doctorate, Porter joined North Carolina State University as a postdoctoral research associate.
Research and career
Porter was appointed to the faculty at Carnegie Mellon University at 1997. Her early research considered the metal contacts for high-power electronic devices and oxide–silicon carbide interfaces. She has since investigated several materials, including transparent conducting films and electrodes as well as organic semiconductors. Her research focusses on the wide bandgap semiconductor gallium oxide. Small amounts of gallium oxide can withstand high electric fields and can be used for highly energy intensive processes. Porter has studied a variety of gallium oxide]polymorphs, including α, β and ε-Ga2O3. In particular, β-Ga2O3 bulk single crystals can be fabricated using low-cost melt-growth methods and can be produced in large wafers.
Porter created the spin-out company SenSevere, which creates chemical sensors based on semi-conductors. The sensors can be used to detect hydrogen in harsh environments, including nuclear reactors and chlorine production cells. When these cells are producing chlorine they produce considerable concentrations of hydrogen, and if this is not removed quickly from the system can result in the formation of hydrogen chloride. In nuclear reactors, hydrogen build up can cause explosions when hydrogen interacts with oxygen and water.
Awards and honours
1999 National Science Foundation CAREER Award
2006 Women and Girls Foundation Women Driving the Material World award
2012 Carnegie Mellon University Philbrook Prize in Engineering
2018 North Carolina State University Hall of Fame
2018 President of the American Vacuum Society
Selected publications
References
Living people
Year of birth missing (living people)
Carnegie Mellon University faculty
Cornell University alumni
North Carolina State University alumni
Women materials scientists and engineers | Lisa M. Porter | [
"Materials_science",
"Technology"
] | 435 | [
"Women materials scientists and engineers",
"Materials scientists and engineers",
"Women in science and technology"
] |
63,405,044 | https://en.wikipedia.org/wiki/Air%20polymer-type%20A | Air polymer-type A, sold under the brand name ExEm Foam, is a drug for the detection of fallopian tube patency (openness) in people with known or suspected infertility. It was approved for use in the United States in November 2019.
Air polymer-type A is infused into the uterus to allow for visual assessment of fallopian tubes during an ultrasound examination called a sonohysterosalpingography.
The most common adverse reactions are pelvic pain and abdominal pain, nausea and faintness (caused by a nerve and blood vessel reaction called vasovagal reaction) and post-procedure spotting.
History
The US Food and Drug Administration (FDA) approved air polymer-type A based on literature reports. To evaluate how well air polymer-type A works, the FDA primarily used data from two trials. Trial A was conducted at a site in Italy and Trial B at three sites in Poland.
Evaluation of side effects was based on multiple literature reports and collected safety reports from countries where air polymer-type A is already approved.
References
Female genital procedures
Medical ultrasonography
Infertility | Air polymer-type A | [
"Chemistry"
] | 229 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
63,405,893 | https://en.wikipedia.org/wiki/NGC%20670 | NGC 670 is a lenticular galaxy located in the Triangulum constellation about 165 million light years from the Milky Way. It was discovered by the German-British astronomer William Herschel in 1786.
See also
List of NGC objects (1–1000)
References
External links
Triangulum
670
Lenticular galaxies
006570 | NGC 670 | [
"Astronomy"
] | 65 | [
"Triangulum",
"Constellations"
] |
63,405,954 | https://en.wikipedia.org/wiki/NGC%20620 | NGC 620 is a spiral galaxy located in the constellation Andromeda about 123 million light-years from the Milky Way. It was discovered by the French astronomer Édouard Stephan in 1871.
See also
List of NGC objects (1–1000)
References
Spiral galaxies
Andromeda (constellation)
0620
005990
Discoveries by Édouard Stephan | NGC 620 | [
"Astronomy"
] | 67 | [
"Andromeda (constellation)",
"Constellations"
] |
63,406,129 | https://en.wikipedia.org/wiki/Susanne%20Viefers | Susanne Friederike Viefers (born 1970) is a German-Norwegian theoretical physicist interested in low-dimensional quantum systems including the Quantum Hall effect, Bose–Einstein condensates, and anyons. She is a professor of theoretical physics at the University of Oslo in Norway.
Education and career
Viefers was born on 28 March 1970 in Orsoy, Germany. She moved to Norway as a teenager, but retains her German citizenship. She did all of her studies at the University of Oslo, earning a bachelor's degree in 1992, a master's degree in 1993, and a doctorate (Dr. Sci.) in 1997. Her dissertation was Field theory of anyons and the fractional quantum Hall effect.
After postdoctoral research at the Nordic Institute for Theoretical Physics in Copenhagen, Denmark, at the University of Jyväskylä in Finland, and at Chalmers University of Technology in Gothenburg, Sweden, she returned to the University of Oslo as an associate professor in 2002, and she was promoted to full professor in 2007.
Recognition
Viefers was elected to the Norwegian Academy of Science and Letters in 2017.
Selected publications
Bøe, Maria Vetleseter & Viefers, Susanne Friederike (2021). Secondary and University Students’ Descriptions of Quantum Uncertainty and the Wave Nature of Quantum Particles. Science & Education. ISSN 0926-7220. doi: 10.1007/s11191-021-00297-w. Full text in Research Archive
Hansson, Thors Hans; Hermanns, Maria; Simon, Steven H & Viefers, Susanne F (2017). Quantum Hall Physics - hierarchies and CFT techniques. Reviews of Modern Physics. ISSN 0034-6861. 89(2). doi: 10.1103/RevModPhys.89.025005. Full text in Research Archive
Meyer, Marius Ladegård; Liabøtrø, Ola & Viefers, Susanne F (2016). Linear dependencies between composite fermion states. Journal of Physics A: Mathematical and Theoretical. ISSN 1751-8113. 49(39). doi: 10.1088/1751-8113/49/39/395201.
Meyer, Marius Ladegård; Sreejith, Ganesh Jaya & Viefers, Susanne F (2014). Rotational properties of two-component Bose gases in the lowest Landau level. Physical Review A. Atomic, Molecular, and Optical Physics (PRA). ISSN 1050-2947. 89(4). doi: 10.1103/PhysRevA.89.043625. Full text in Research Archive
Manninen, M; Viefers, Susanne F & Reimann, S (2012). Quantum rings for beginners II: Bosons versus fermions. Physica. E, Low-Dimensional systems and nanostructures. ISSN 1386-9477. 46, p. 119–132. doi: 10.1016/j.physe.2012.09.013.
References
External links
Home page
1970 births
Living people
21st-century German physicists
Norwegian physicists
21st-century women physicists
Quantum physicists
University of Oslo alumni
Academic staff of the University of Oslo
Members of the Norwegian Academy of Science and Letters | Susanne Viefers | [
"Physics"
] | 684 | [
"Quantum physicists",
"Quantum mechanics"
] |
63,406,456 | https://en.wikipedia.org/wiki/Laver%27s%20theorem | Laver's theorem, in order theory, states that order embeddability of countable total orders is a well-quasi-ordering. That is, for every infinite sequence of totally-ordered countable sets, there exists an order embedding from an earlier member of the sequence to a later member. This result was previously known as Fraïssé's conjecture, after Roland Fraïssé, who conjectured it in 1948; Richard Laver proved the conjecture in 1971. More generally, Laver proved the same result for order embeddings of countable unions of scattered orders.
In reverse mathematics, the version of the theorem for countable orders is denoted FRA (for Fraïssé) and the version for countable unions of scattered orders is denoted LAV (for Laver). In terms of the "big five" systems of second-order arithmetic, FRA is known to fall in strength somewhere between the strongest two systems, -CA0 and ATR0, and to be weaker than -CA0. However, it remains open whether it is equivalent to ATR0 or strictly between these two systems in strength.
See also
Dushnik–Miller theorem
References
Order theory | Laver's theorem | [
"Mathematics"
] | 242 | [
"Order theory"
] |
63,406,512 | https://en.wikipedia.org/wiki/Blue%20space | In urban planning and design, blue space (or blue infrastructure) comprises areas dominated by surface waterbodies or watercourses. In conjunction with greenspace (parks, gardens, etc. specifically: urban open space), it may help in reducing the risks of heat-related illness from high urban temperatures (urban heat island).
Substantial urban waterbodies naturally exist as integral features of the geography of many cities because of their historical development, for example the River Thames in London.
Accessible blue spaces can help revitalizing neighborhoods and promote increased social connectedness as seen on waterfront renovation projects like the Chattanooga Waterfront (Chattanooga, Tennessee), the CityDeck in Green Bay, Wisconsin, or the Brooklyn Bridge Park in New York City, further enhanced by waterfront festivals such as the Christmas lights in Medellin, in Colombia. Design guidelines promoting healthy buildings -such as, WELL -managed by The International WELL Building Institute™ (IWBI™), or Fitwel -developed and managed by The Center for Active Design (CfAD), recommend incorporating including and water features as a strategy to improve the health and wellness of the building occupants, and "the 9 foundations of a Healthy Building" -developed at Harvard T.H. Chan School of Public Health-, also recommends indoor access to nature views or nature-inspired elements.
Because neighborhoods with access to attractive natural features are susceptible to gentrification, the social benefits associated with waterbodies can be unequally distributed, with less affluent areas lacking access to good quality blue spaces.
Health benefits
Proximity to water bodies may bring some risks to humans, like water-borne diseases in drinking water, flooding risks, or drowning. But scientific evidence shows that exposure to blue spaces is also associated with a variety of health benefits to those near water bodies.
This is described by marine biologist Wallace J. Nichols in his book Blue Mind. Another of the mechanisms by which this phenomenon can be explained is by the Biophilia hypothesis developed by Edward O. Wilson. This theory states that humans have developed a strong connection with nature throughout their evolution that leads to subconscious seeking for natural environments, including green and blue spaces.
Recent research has identified three main pathways that can further explain why proximity to green and blue spaces can be beneficial to health.
Mitigation addresses these health benefits in relationship to the physical improvements that natural environments bring to the built environment, such as reduction of urban heat island, traffic air pollution or traffic noise.
Instoration focuses on the promotion of physical activity and other positive outcomes associated with increased physical activity and social connectivity promoted by natural spaces.
Restoration explains how the non-threatening characteristics of the natural environments may reduce negative feelings and increase cognitive restoration.
Assessing the environmental benefits of a blue space intervention can be done by conducting a Health impact assessment (HIA).
Effects on physical health
Increased physical activity
A variety of studies have found that people living near coastal areas, are less sedentary more likely to engage in moderate and vigorous physical activity adequate for health, which could be explained due to the encouraging presence of walk paths along the coast. Another possible explanation is found in the aesthetical attributes of blue spaces that may motivate individuals to engage in physical activities on blue spaces. A study in England found that although more intense activities were conducted on visits to countryside and urban green spaces compared to visits to coastal environments, coastal visits were associated with the highest overall energy expenditure due duration of activity in coastal environments being longer. Results differed by the urbanity or rurality of the respondent's residence and also how far respondents travelled to their destination.
Proximity to water bodies alone is not enough to promote increased levels of physical activity, as those bodies need to be accessible to people. A study focusing on teenagers found that those living near beaches that had a major road between their homes and the water body had lower levels of physical activity than those with a direct access to the beach.
Reduced obesity
Visiting blue spaces may reduce obesity as it promotes increased physical activity. One study has suggested that living far from usable green space or waterfront in urban areas may increase the risk of obesity.
Improved respiratory health
Living near blue spaces can improve the quality of life of people with respiratory diseases, such as asthma, which could be explained by the mists and sprays generated by the water movement as shown on a study measuring the impact in health of green and blue spaces for those with chronic obstructive pulmonary disease (COPD).
Mental health
Improved overall health
Researchers found that individuals across 15 countries in Europe and Australia report better general health when they live closer to the coast or visit it more often. Researchers also found a reduction of psychiatric cases on people living near green or coastal areas. Some of the studies found that ocean exposure or running along river helped war veterans suffering from PTSD. Others found that engaging in water-related activities such as surfing can help coping with mental health issues and help developing self-confidence and self-reliance skills. A large study looking at links between childhood exposure to blue spaces and adult well-being found that exposure to blue spaces in childhood was associated with better adult well-being.
Improved mood and happiness
Exposure to blue spaces is also linked to increased happiness. A group of researchers studying the effect of green and blue spaces on happiness used a mobile app to track mood feelings of people when they were near water landscapes. The researchers found increased levels of happiness in people near water bodies. Consistently with the findings focusing on physical health, the positive effects on mood associated to blue spaces seem to diminish as the distance between the residence and the water increases.
Improved recovery from drug and alcohol addiction
Educational interventions in blue spaces - such as sailing - have been shown to have positive perceived effects on people undergoing drug and alcohol rehabilitation.
Quality assessment tools
In order to understand how blue spaces may influence health-promoting behaviours, a group of researchers that focuses on blue spaces has developed a set of novel tools specifically designed to quantify the quality and potential health benefits of these spaces, risks associated with their use, and environmental quality. The BlueHealth Environmental Assessment Tool (BEAT) - enables comparable assessment of environmental aspects and attributes that influence access to, use of and health-promoting activities in blue spaces. The tool has been developed to be used by communities and urban/landscape designers.
See also
Urban green space
Urban ecology
Urban water management
Green belt
Healthy city
Healthy buildings
Public health
Green infrastructure
References
Urban design
Public health
Rivers
Bodies of water
Coastal and oceanic landforms
Lakes | Blue space | [
"Environmental_science"
] | 1,302 | [
"Lakes",
"Hydrology"
] |
63,409,943 | https://en.wikipedia.org/wiki/NAIL-MS | NAIL-MS (short for nucleic acid isotope labeling coupled mass spectrometry) is a technique based on mass spectrometry used for the investigation of nucleic acids and its modifications. It enables a variety of experiment designs to study the underlying mechanism of RNA biology in vivo. For example, the dynamic behaviour of nucleic acids in living cells, especially of RNA modifications, can be followed in more detail.
Theory
NAIL-MS is used to study RNA modification mechanisms. Therefore, cells in culture are first fed with stable isotope labeled nutrients and the cells incorporate these into their biomolecules. After purification of the nucleic acids, most often RNA, analysis is done by mass spectrometry. Mass spectrometry is an analytical technique that measures the mass-to-charge ratio of ions. Pairs of chemically identical nucleosides of different stable-isotope composition can be differentiated in a mass spectrometer due to their mass difference. Unlabeled nucleosides can therefore be distinguished from their stable isotope labeled isotopologues. For most NAIL-MS approaches it is crucial that the labeled nucleosides are more than 2 Da heavier than the unlabeled ones. This is because 1.1% of naturally occurring carbon atoms are 13C isotopes. In the case of nucleosides this leads to a mass increase of 1 Da in ~10% of the nucleosides. This signal would disturb the final evaluation of the measurement.
NAIL-MS can be used to investigate RNA modification dynamics by changing the labeled nutrients of the corresponding growth medium during the experiment. Furthermore, cell populations can be compared directly with each other without effects of purification bias. Furthermore, it can be used for the production of biosynthetic isotopologues of most nucleosides which are needed for quantification by mass spectrometry and even for the discovery of yet unknown RNA modifications.
General procedure
In general, cells are cultivated in unlabeled or stable (non-radioactive) isotope labeled media. For example, the medium can contain glucose labeled with six carbon-13 atoms (13C) instead of the normal carbon-12 (12C). Cells growing in this medium, will, depending on model organism, incorporate the heavy glucose into all of their RNA molecules. Thereafter, all nucleotides are 5 Da heavier than their unlabeled isotopologues due to a complete carbon labeling of the ribose. After cultivation and appropriate labeling of the cells, they are generally harvested using phenol/chloroform/guanidinium isothiocyanate. Other extraction methods are possible and sometimes needed (e.g. for yeast). RNA is then isolated by Phenol-Chloroform extraction and iso-Propanol precipitation. Further purification of specific RNA species (e.g. rRNA, tRNA) is usually done by size-exclusion chromatography (SEC) but other approaches are available as well. For most applications the final product needs to be enzymatically digested to nucleosides before analysis by LC-MS. Therefore, digestion enzymes such as benzonase, NP1 and CIP are used. Typically, a triple quadrupole in MRM mode is used for the measurements.
Labeling of cells
How the labeling of RNA molecules is achieved depends on the model organism. For E.coli (bacteria) the minimum medium M9 can be used and supplemented with the stable isotope labeled variants of the needed salts. This enables labeling with 13C-carbon, 15N-nitrogen, 34S-sulfur and 2H-hydrogen. In S.cerevisiae (yeast) there are currently two possibilities: First, the use of commercially available complete growth medium, which enables labeling with 13C-carbon and/or 15N-nitrogen and second the use of minimal YNB medium which has to be supplemented with several amino acids and glucose which can be added as stable isotope labeled variants in order to achieve 13C-carbon, 15N-nitrogen and 2H-hydrogen labeling of RNA.
While labeling in model organisms like E.coli and S.cerevisiae is fairly simple, stable isotope labeling in cell culture is much more challenging as the composition of the growth media is much more complex. Neither the supplementation of stable isotope labeled glucose nor the supplementation of stable isotope labeled variants of simple precursors of nucleoside biosynthesis such as glutamine and/or aspartate is sufficient for a defined mass increase higher than 2 Da. Instead, most cells kept in cell culture can be fed with stable isotope labeled methionine for labeling of methyl groups and with stable isotope labeled variants of adenin and uridine for labeling of the nucleoside's base body. Special care must be taken when supplementing the medium with FBS (fetal bovine serum), as it also contains small metabolites used for the biosynthesis of nucleosides. The use of dialyzed FBS is therefore advisable when defined labeling of all nucleosides is desired.
Applications
With NAIL-MS different experiment designs are possible.
Production of SILIS
NAIL-MS can be used to produce stable isotope labeled internal standards (ISTD). Therefore, cells are grown in medium which results in complete labeling of all nucleosides. The purified mix of nucleosides can then be used as ISTD which is needed for accurate absolute quantification of nucleosides by mass spectrometry. This mixture of labeled nucleosides is also referred to as SILIS (stable isotope labeled internal standard). The advantage of this approach is, that all modifications present in an organism can thereby be biosynthesized as labeled compounds. The production of SILIS was already done before the term NAIL-MS emerged.
Comparative Experiments
A comparative NAIL-MS experiment is quite similar to a SILAC experiment but for RNA instead of proteins. First, two populations of the respective cells are cultivated. One of the cell populations is fed with growth medium containing unlabeled nutrients, whereas the second population is fed with growth medium containing stable isotope labeled nutrients. The cells then incorporate the respective isotopologues into their RNA molecules. One of the cell populations serves as a control group whereas the other is subject to the associated research (e.g. KO strain, stress). Upon harvesting of the two cell populations they are mixed and co-processed together to exclude purification-bias. Due to the distinct masses of incorporated nutrients into the nucleosides a differentiation of the two cell populations is possible by mass spectrometry.
Pulse-Chase Experiments
Upon initiation of a pulse-chase experiment the medium is switched from medium(1) to medium(2). The two media must only differ in their isotope content. Thereby it is possible to distinguish between RNA molecules already existent before experiment initiation (= RNA molecules grown in medium(1)) and RNA molecules that are newly transcribed after experiment initiation (= RNA molecules grown in medium(2)). This allows the detailed study of modification dynamics in vivo. The supplementation of labeled methionine in either medium(1) or medium(2) allows the tracing of methylation processes. Other isotopically labeled metabolites potentially allow for further modification analysis.
Altogether NAIL-MS enables the investigation of RNA modification dynamics by mass spectrometry. With this technique, enzymatic demethylation has been observed for several RNA damages inside living bacteria.
Discovery of new RNA modifications
For the discovery of uncharacterized modifications cells are grown in unlabeled or 13C‑labeled or 15N‑labeled or 2H‑labeled or 34S‑labeled medium. Unknown signals occurring during mass spectrometry are then inspected in all differentially labeled cultures. If retention times of unknown compounds with appropriately divergent m/z values overlap, a sum formula of the compound can be postulated by calculating the mass differences of the overlapping signal in the differentially labeled cultures. With this method several new RNA modifications could be discovered. This experimental design also was the initial idea that started the concept of NAIL-MS.
Oligonucleotide NAIL-MS
NAIL-MS can also be applied to oligonucleotide analysis by mass spectrometry. This is useful when the sequence information is to be retained.
References
External links
https://www.cup.lmu.de/oc/kellner/research/
https://iimcb.genesilico.pl/modomics/
Biochemistry detection methods
Biotechnology
Epigenetics
Genetics techniques
RNA
Isotopes
Mass spectrometry | NAIL-MS | [
"Physics",
"Chemistry",
"Engineering",
"Biology"
] | 1,789 | [
"Biochemistry methods",
"Genetics techniques",
"Spectrum (physical sciences)",
"Instrumental analysis",
"Mass",
"Biochemistry detection methods",
"Isotopes",
"Chemical tests",
"Genetic engineering",
"Biotechnology",
"Mass spectrometry",
"nan",
"Nuclear physics",
"Matter"
] |
63,410,338 | https://en.wikipedia.org/wiki/Post%20and%20Logistics%20Union | The Post and Logistics Union (, PAU) is a trade union, principally representing postal workers, in Finland.
The union was founded on 1 June 2005, when the Postal Union merged with the Postal Officers' Union. The two unions, originally representing separate groups of workers, and affiliated to different union federations, had increasingly come to co-operate. The new union chose to affiliate to the Central Organisation of Finnish Trade Unions.
By 2007, the union represented 82% of eligible workers in the postal service, with approximately half the members being women. As of 2020, the union had 25,004 members.
Presidents
2005: Esa Vilkuna
2014: Heidi Nieminen
References
Postal trade unions
Trade unions in Finland
Trade unions established in 2005 | Post and Logistics Union | [
"Physics"
] | 150 | [
"Physical systems",
"Transport",
"Transport stubs"
] |
63,410,457 | https://en.wikipedia.org/wiki/NGC%20820 | NGC 820 is a spiral galaxy located in the constellation Aries about 210 million light-years from the Milky Way. It was discovered by British astronomer John Herschel in 1828.
One supernova has been observed in NGC 820: SN 2002ea (type IIn, mag. 17.7).
See also
List of NGC objects (1–1000)
References
External links
Spiral galaxies
0820
Aries (constellation)
008165 | NGC 820 | [
"Astronomy"
] | 90 | [
"Aries (constellation)",
"Constellations"
] |
63,410,530 | https://en.wikipedia.org/wiki/NGC%20830 | NGC 830 is a barred lenticular galaxy in the constellation Cetus. It is estimated to be about 170 million light-years from the Milky Way and has a diameter of approximately 70,000 light years.
See also
List of NGC objects (1–1000)
References
External links
Barred lenticular galaxies
0830
Cetus
008201
Markarian galaxies | NGC 830 | [
"Astronomy"
] | 73 | [
"Cetus",
"Constellations"
] |
63,410,575 | https://en.wikipedia.org/wiki/NGC%20850 | NGC 850 is a lenticular galaxy in the constellation Cetus. It is estimated to be 300 million light-years from the Milky Way and has a diameter of approximately 130,000 ly.
See also
List of NGC objects (1–1000)
References
External links
Lenticular galaxies
0850
Cetus
008369 | NGC 850 | [
"Astronomy"
] | 66 | [
"Cetus",
"Constellations"
] |
63,410,607 | https://en.wikipedia.org/wiki/NGC%20840 | NGC 840 is a barred spiral galaxy in the constellation Cetus south of the ecliptic. It is estimated to be about 300 million light-years from the Milky Way and has a diameter of approximately 175,000 ly.
See also
List of NGC objects (1–1000)
References
External links
Barred spiral galaxies
0840
Cetus
008293 | NGC 840 | [
"Astronomy"
] | 73 | [
"Cetus",
"Constellations"
] |
63,410,698 | https://en.wikipedia.org/wiki/NGC%20860 | NGC 860 is an elliptical galaxy located in the constellation Triangulum.
It is about 410 million light-years from the Milky Way. It was discovered by the French astronomer Édouard Stephan on 18 September 1871.
See also
List of NGC objects (1–1000)
References
External links
Elliptical galaxies
0860
Triangulum
008606
Discoveries by Édouard Stephan
Astronomical objects discovered in 1871 | NGC 860 | [
"Astronomy"
] | 78 | [
"Triangulum",
"Constellations"
] |
63,410,702 | https://en.wikipedia.org/wiki/Postal%20Union | The Postal Union () was a trade union representing postal workers in Finland.
The first conference of postal service workers in Finland was held in 1901, but only in 1906 did they agree to form a union, at a meeting in Tampere.
In 1945, the union affiliated to the Finnish Federation of Trade Unions, but it resigned in 1960, instead joining the Joint Organisation of State Employees (VTY). Through this federation, in 1969, it became affiliated to the Central Organisation of Finnish Trade Unions (SAK). In 1995, it left the VTY and affiliated to the SAK in its own right. By 1998, it had 26,153 members.
From 2000, the union worked increasingly closely with the Postal Officers' Union, and the two merged in 2005, forming the Post and Logistics Union.
References
Postal trade unions
Trade unions in Finland
Trade unions established in 1906
Trade unions disestablished in 2005
1906 establishments in Finland | Postal Union | [
"Physics"
] | 189 | [
"Physical systems",
"Transport",
"Transport stubs"
] |
63,411,286 | https://en.wikipedia.org/wiki/Infeld%E2%80%93Van%20der%20Waerden%20symbols | The Infeld–Van der Waerden symbols, sometimes called simply Van der Waerden symbols, are an invariant symbol associated to the Lorentz group used in quantum field theory. They are named after Leopold Infeld and Bartel Leendert van der Waerden.
The Infeld–Van der Waerden symbols are index notation for Clifford multiplication of covectors on left handed spinors giving a right-handed spinors or vice versa, i.e. they are off diagonal blocks of gamma matrices. The symbols are typically denoted in Van der Waerden notation as
and so have one Lorentz index (m), one left-handed (undotted Greek), and one right-handed (dotted Greek) Weyl spinor index. They satisfy
They need not be constant, however, and can therefore be formulated on curved space time.
Background
The existence of this invariant symbol follows from a result in the representation theory of the Lorentz group or more properly its Lie algebra. Labeling irreducible representations by , the spinor and its complex conjugate representations are the left and right fundamental representations
and
while the tangent vectors live in the vector representation
The tensor product of one left and right fundamental representation is the vector representation,. A dual statement is that the tensor product of the vector, left, and right fundamental representations contains the trivial representation which is in fact generated by the construction of the Lie algebra representations through the Clifford algebra (see below)
Representations of the Clifford algebra
Consider the space of positive Weyl spinors of a Lorentzian vector space with dual .
Then the negative Weyl spinors can be identified with the vector space of complex conjugate dual spinors.
The Weyl spinors implement "two halves of a Clifford algebra representation" i.e. they come with a multiplication by covectors implemented as maps
and
which we will call Infeld–Van der Waerden maps. Note that in a natural way we can also think of the maps as a sesquilinear map associating a vector to a left and righthand spinor
respectively .
That the Infeld–Van der Waerden maps implement "two halves of a Clifford algebra representation" means that for covectors
resp.
,
so that if we define
then
Therefore extends to a proper Clifford algebra representation .
The Infeld–Van der Waerden maps are real (or hermitian) in the sense that the complex conjugate dual maps
coincides (for a real covector ) :
.
Likewise we have .
Now the Infeld the Infeld–Van der Waerden symbols are the components of the maps and with respect to bases of and with induced bases on and . Concretely, if T is the tangent space at a point O with local coordinates () so that is a basis for and is a basis for , and () is a basis for , is a dual basis for with complex conjugate dual basis of , then
Using local frames of the (co)tangent bundle and a Weyl spinor bundle, the construction carries over to a differentiable manifold with a spinor bundle.
Applications
The symbols are of fundamental importance for calculations in quantum field theory in curved spacetime, and in supersymmetry. In the presence of a tetrad for "soldering" local Lorentz indices to tangent indices, the contracted version can also be thought of as a soldering form for building a tangent vector out of a pair of left and right Weyl spinors.
Conventions
In flat Minkowski space, A standard component representation is in terms of the Pauli matrices, hence the notation. In an orthonormal basis with a standard spin frame, the conventional components are
Note that these are the blocks of the gamma matrices in the Weyl Chiral basis convention. There are, however, many conventions.
Citations
References
Mathematical physics
Representation theory of Lie groups
Spinors | Infeld–Van der Waerden symbols | [
"Physics",
"Mathematics"
] | 787 | [
"Applied mathematics",
"Theoretical physics",
"Mathematical physics"
] |
63,411,790 | https://en.wikipedia.org/wiki/Cloakmaker | A Cloak maker worked in the garment industry, often in an enterprise whose workers were represented by a union.
In the 1920s, there were more than 50,000 people employed as cloakmakers.
Much of this industry was centered in NYC. While most of the cloakmakers were Jewish women, the next largest group, although much smaller in number, were Italian women.
Cloakmakers were a part of those known as clothing-workers, including those who made cloaks, suits and skirts.
Other areas where this industry was strong included Chicago and Cincinnati.
Unions
Suffragist Theresa Malkiel organized a union of cloakmakers in 1892. Other areas of the needle trade were not unionized until years later, of whom in 1912 over 80% were Jewish.
This occupation involved making or repairing garments that contained animal fur. The high end of this profession focused on fur coats. A
1915 New York Times article about 75,000 garment workers said "Cloakmakers take the lead."
The garment industry's strikes were neither rare nor long-lasting.
References
Sources
Manufacturing
Clothing industry
History of clothing (Western fashion) | Cloakmaker | [
"Engineering"
] | 222 | [
"Manufacturing",
"Mechanical engineering"
] |
63,411,811 | https://en.wikipedia.org/wiki/Spendor | Spendor is a British loudspeaker manufacturing company founded in 1969 by audio engineer Spencer Hughes (1924–1983) and his wife Dorothy. It is located in East Sussex. The name was derived from the first names of both.
Research in the 1960s
Spencer Hughes worked in an investigation team of the BBC research department in the 1960s. Though journeying into Television, this was a time period when the BBC's licence budget meant the main transmission output was still radio, the imperative behind that of a BBC licensed loudspeaker was that (within the physical confines of a small bookshelf speaker) the principle objective of the loudspeaker was to reproduce an output audio signal with an acoustic fidelity to an original radio presenter's voice; principally within the entire spoken vocal range. To this end the resultant, and historically important BBC LS35A loudspeaker hit the retail market, the optional license meant any manufacture could procure a license to produce the LS35A design only if they were able to build a speaker which matched the same high fidelity standard the BBC had worked to achieve. The goal of the BBC R&D team had been reached with the original LS35A standard was now available to consumers who had the means to buy an amplification and loudspeaker system guaranteed to bring in to their homes the exact same sonic signature BBC sound engineers heard while recording and during replay. An alternative, the unwieldily, but sonically superior Quad Acoustics Electrostatic Loudspeaker ("ELS") were simply too large and pricey for most audiophiles.
One resulting offshoot of the research was a membrane made from a polystyrene ("Bextrene") for mid-range speakers or woofers.
History
Start
In the first days Dorothy assisted with coil winding expertise, later she took over the general management.
The first product was the BC1, which Spencer designed while still working for the BBC. Several other designs followed, the BC2, BC3, SA1, SP1 and other. Spendor also made the BBC LS3/5a under licence from the BBC.
The BC1 is bigger than a LS3/5a and also uses a Bextrene-membrane and was used in many radio stations, too. As a consequence many UK speaker designs are influenced by this improvement of sound quality through reduced colouration and greater consistency as well as the stereo imaging. The BC1 was built with smaller modifications until 1994.
The present Head of Engineering, Terry Miles, started as Spencer Hughes’ assistant in 1975.
Derek Hughes' time at Spendor
Derek Hughes, son of Spencer and his wife Dorothy, worked at Spendor (in his letter from 1980 Spencer mentioned him as assist with research and development and general running of the factory). After the untimely death of Spencer in 1983 he worked with his mother in the capacity of Technical Director, producing the original versions of what is now the Classic Series, most notably the SP1/2, SP2 and the S100 and he did amongst others the redesign of the 3/5 1998 and is still working at loudspeakers as freelance consultant designer.
Since 2000
Since the year 2000 the company is owned by Philip Swift a speaker designer and co-founder of Audiolab, who personally knew Spencer Hughes. then sold to Ajay Shirke. Spendor develops and manufactures all components in UK.
Round about these days Spendor enlarged their product range by floorstanding loudspeakers, first with models of a S line, currently be found as loudspeakers of A line and higher end D line.
Products 2020
A line: compact and floorstanding speakers
Classic: until 2018 without floorstanding speakers
D line: compact and floorstanding speakers
See also
Studio monitor
References
External links
Homepage of the company Spendor
Audio engineering
BBC
Audio equipment manufacturers of the United Kingdom
Loudspeaker manufacturers | Spendor | [
"Engineering"
] | 801 | [
"Electrical engineering",
"Audio engineering"
] |
63,412,394 | https://en.wikipedia.org/wiki/Roofing%20slates | Roofing slates are roofing tiles made out of slate. The rock is split into thin sheets which are cut to the requires size before shipment. This contrasts to slabs which are milled to produce larger structural components. They are the primary product of the slate industry.
History
.
The Romans were the first to mine and install standard-sized slate on roofs.
In his writings, Pliny the Elder mentions the existence of slate in Liguria, near Genoa.
Modern production
The world's biggest consumer of slate is France, followed by the UK, USA and Germany.
In 2012, Spain produced more than of slate worth about $380 million. This made it the largest slate producer in the world, followed by China and Brazil.
See also
Roofing material
List of commercially available roofing materials
Slate industry in Wales (has information about different sizes of roofing slates)
References
Roofs
Stone buildings
Slate | Roofing slates | [
"Technology",
"Engineering"
] | 182 | [
"Structural system",
"Structural engineering",
"Roofs"
] |
63,412,780 | https://en.wikipedia.org/wiki/Signed%20set | In mathematics, a signed set is a set of elements together with an assignment of a sign (positive or negative) to each element of the set.
Representation
Signed sets may be represented mathematically as an ordered pair of disjoint sets, one set for their positive elements and another for their negative elements. Alternatively, they may be represented as a Boolean function, a function whose domain is the underlying unsigned set (possibly specified explicitly as a separate part of the representation) and whose range is a two-element set representing the signs.
Signed sets may also be called -graded sets.
Application
Signed sets are fundamental to the definition of oriented matroids.
They may also be used to define the faces of a hypercube. If the hypercube consists of all points in Euclidean space of a given dimension whose Cartesian coordinates are in the interval , then a signed subset of the coordinate axes can be used to specify the points whose coordinates within the subset are or (according to the sign in the signed subset) and whose other coordinates may be anywhere in the interval . This subset of points forms a face, whose codimension is the cardinality of the signed subset.
Combinatorics
Enumeration
The number of signed subsets of a given finite set of elements is , a power of three, because there are three choices for each element: it may be absent from the subset, present with positive sign, or present with negative sign. For the same reason, the number of signed subsets of cardinality is
and summing these gives an instance of the binomial theorem,
Intersecting families
An analogue of the Erdős–Ko–Rado theorem on intersecting families of sets holds also for signed sets. The intersection of two signed sets is defined to be the signed set of elements that belong to both and have the same sign in both. According to this theorem, for any a collection of signed subsets of an -element set, all having cardinality and all pairs having a non-empty intersection, the number of signed subsets in the collection is at most
For instance, an intersecting family of this size can be obtained by choosing the sign of a single fixed element, and taking the family to be all signed subsets of cardinality that contain this element with this sign. For this theorem follows immediately from the unsigned Erdős–Ko–Rado theorem, as the unsigned versions of the subsets form an intersecting family and each unsigned set can correspond to at most signed sets. However, for larger values of a different proof is needed.
References
Set theory | Signed set | [
"Mathematics"
] | 517 | [
"Mathematical logic",
"Set theory"
] |
63,414,661 | https://en.wikipedia.org/wiki/NGC%20890 | NGC 890 is a lenticular galaxy in the constellation Triangulum. It is estimated to be 180 million light-years from the Milky Way and has a diameter of approximately 130,000 ly. NGC 890 was discovered on September 13, 1784 by Wilhelm Herschel.
See also
List of NGC objects (1–1000)
References
0890
Lenticular galaxies
Triangulum
008997 | NGC 890 | [
"Astronomy"
] | 83 | [
"Triangulum",
"Constellations"
] |
63,414,741 | https://en.wikipedia.org/wiki/NGC%20900 | NGC 900 is a lenticular galaxy located in the constellation Aries about 430 million light-years from the Milky Way. It was discovered by the German astronomer Albert Marth in 1864.
See also
List of NGC objects (1–1000)
References
External links
0900
Lenticular galaxies
Aries (constellation)
009079 | NGC 900 | [
"Astronomy"
] | 67 | [
"Aries (constellation)",
"Constellations"
] |
56,440,744 | https://en.wikipedia.org/wiki/ISO%207010 | ISO 7010 is an International Organization for Standardization technical standard for graphical hazard symbols on hazard and safety signs, including those indicating emergency exits. It uses colours and principles set out in ISO 3864 for these symbols, and is intended to provide "safety information that relies as little as possible on the use of words to achieve understanding."
The standard was published in October 2003, splitting off from ISO 3864:1984, which set out design standards and colors of safety signage and merging ISO 6309:1987, Fire protection - Safety signs to create a unique and distinct standard for safety symbols.
, the latest version is ISO 7010:2019, with 8 published amendments. This revision canceled and replaced ISO 20712-1:2008, incorporating the water safety signs and beach safety flags specified in it.
Shape and colour
ISO 7010 specifies five combinations of shape and colour to distinguish between the type of information presented.
List
ISO registers and lists recommended pictograms, which it calls "safety signs", on its website, ISO.org. The ISO standard provides a registered number for pictograms that have officially been made part of the ISO 7010 standard. Corresponding with the categories above, in ISO parlance, "E" numbers refer to Emergency (signs showing a safe condition), "F" numbers refer to Fire protection, "P" numbers refer to Prohibited actions, "M" numbers refer to Mandatory actions, and "W" numbers refer to Warnings of hazards.
According to the related ISO 3864-1 standard, if a symbol does not exist for a situation, the recommended solution is to use the relevant 'general' symbol (M001, P001, W001), along with a supplemental text message.
Safe condition
Crescent variant
ISO 7010 states on all symbols with a first aid cross, that it "may be replaced with another element appropriate to cultural requirements". In countries with a Muslim-majority population, an appropriate symbol is the crescent.
Fire protection
Mandatory
Prohibition
Warning
Withdrawn symbols
The following symbols were previously part of ISO 7010, but have since been withdrawn from the standard.
Symbols From Regional Variations of ISO 7010
France
Netherlands
See also
Hazard symbol
ISO 3864 – Safety colors and safety signs
ISO 7001 – Public Information Symbols
ISO 21482 – A separate standard for a specific radiation safety sign for specific applications
ANSI Z535 – The United States national standard for safety information
Directive 92/58/EEC – Safety signs used in the European Union
GHS hazard pictograms – Symbols used by the Globally Harmonized System of Classification and Labelling of Chemicals
References
External links
ISO 7010:2019 Graphical symbols -- Safety colours and safety signs -- Registered safety signs
07010
Symbols
Pictograms | ISO 7010 | [
"Mathematics"
] | 557 | [
"Symbols",
"Pictograms"
] |
56,442,223 | https://en.wikipedia.org/wiki/Blocknots | Blocknots were random sequences of numbers contained in a book and organized by numbered rows and columns and were used as additives in the reciphering of Soviet Union codes, during World War II. The Blocknot consisted of fifty sheets of 5-figure random additive, 100 additive groups to a sheet. No sheet was used more than once, thus the blocknots were in effect a form of one-time pad. The Soviet Unions highest grade ciphers that were used in the East, were the 5-figure codebook enciphered with the Blocknot book, and were generally considered unbreakable.
Technical Description
Blocknots were distributed centrally from an office in Moscow. Every Blocknot contained 5-figure groups in a number of sheets, for the enciphering of 5-figure messages. The encipherment was effected by applying additives taken from the pad, of which 50-100 5-figure groups appeared. Each pad had a 5-figure number and each sheet had a 2-figure number running consecutively. There were 5 different types of Blocknots, in two different categories
The Individual in which each table of random numbers was used only once.
The General in which each page of the Blocknot was valid for one day. The security of the additive sequence rested on the choice of different starting points for each message. In 5-figure messages, the blocknot was one of the first 10 Groups in the message. Its position changed at long intervals, but was always easy to re-identify. The Russians differentiated between three types of blocks:
The 3-block, DRIERBLOCK. I-block for Individual Block: 50 pages, additive read off in one direction only. The messages could be used and read only between 2 wireless telegraphy stations on one net.
The 6-block, SECHSERBLOCK. Z-block for Circular Block: 30 pages, additive read off in either direction. The messages could be used and read, between all W/T stations in a net.
The 2-block, ZWEIERBLOCK. OS-block. Used only in traffic from lower to higher formations.
Two other types were used, in lower echelons.
Notblock: Used in an emergency.
Blocknot used for passing on traffic.
The distribution of Blocknots was carried out centrally from Moscow to Army Groups then to Armies. The Army was responsible for their distribution throughout the lower levels of the army down to company level. Independent units took their cipher material with them. Occasionally the same blocknot was distributed to two units on different parts of the front, which enabled Depth to be established. Records of all Blocknots used were kept in Berlin and when a repeat was noticed a BLOCKNOT ANGEBOT message was sent out to all German Signals units, to indicate that it may have been possible to break the code using it. There was no certainty in this.
A cryptanalyst with the General der Nachrichtenaufklärung stated while being interrogated by TICOM:
It seems that depths of up to 8 were established at the beginning of the Russian Campaign but that no 5-figure code was broken after May 1943
German cryptanalysts who were prisoners of war stated under interrogation, that each of the figures 0 to 9 were placed en clair usually within the first ten groups of the text or sometimes at the end. One indicator was the Blocknot number and the consisted of two random figures, the figure representing the type, and the remaining two, the page of the Blocknot being used.
In long messages, 000000 was placed in the message when the end of a page had been reached.
Chi number
The Chi-number was the serial numbering of all 5-figure messages passing through the hands of the Cipher Officer, starting on the first of January and ending on thirty-first December of the current year. It always appeared as the last group in an intercepted message, e.g. 00001 on the 1st January, or when the unit was newly set up. The progression of Chi-numbers was carefully observed and recorded in the form of a graph. A Russian corps had about 10 5-figure messages per day, and Army about 20-30 and a Front about 60-100. After only a relatively short time, the individual curves separated sharply and the type of formation could be recognized by the height of the Chi-number alone.
Monitoring
Blocknots were tracked in a card index, that was maintained by the Signal Intelligence Evaluation Centre (NAAS). The NAAS functionality included evaluation and traffic analysis, cryptanalysis, collation and dissemination of intelligence. The card index, which was one amongst several Card Indexes. A careful recording and study of blocks provided the positive clues in the identification and tracking of formations using 5-figure ciphers. The index was subdivided into two files:
Search card index, contained all blocknots and chi-numbers whether or not they were known.
Unit card index, contained only known Block and Chi-numbers.
Inspector Berger, who was the chief cryptanalyst of NAAS 1 stated that the two files formed:
The most important and surest instruments for identifying Russian radio nets, known to him.
The Blocknots were also used in the Stationary Intercept Company (Feste), the military unit that were designed to work at a lower level to the NAAS, at the Army level and were semi-motorized, and closer to the front. The Feste used the Blocknot value along with several other parameters to build a network diagram. The network diagram was studied extensively, as part of a 6-stage process, that involved several departments within the Feste. The final outcome was a metric which determined the most interesting circuit for traffic monitoring, and least interesting, where monitoring of traffic should cease.
Analysis
Johannes Marquart was a mathematician and cryptanalyst who initially worked for Inspectorate 7/VI and later led Referat Ia of Group IV of the General der Nachrichtenaufklärung. Marquart was assigned the study of the Soviet Union Blocknot traffic. Marquart and his unit conducted extensive research in an attempt to discover the method by which they were produced. All the counts which they made, however, failed to reveal any non-random characteristics in the design of the tables, and while they thought the Blocknots must have been generated by machine, they were never able to draw any concrete deductions as a result of their research.
Example
The Soviet 3rd Guard Tank Army transmits a 5-figure message with the Blocknot of 37581 (one of the first 10 groups in the message). On the same day the Block 37582 was used by the same formation. The next day 37583 appeared. Thereafter, for a period, the Army was not heard by German Wireless telegraphy intercept operators, as it was maintaining wireless silence. After a few days, an unidentified net with the Blocknot 37588 is picked up. This message net is claimed, because of the proximity of the blocks (88/83) to be the 3rd Guard Tank Army. The missing Blocknots 84-87 were presumably used in telegraphic, telephonic or courier communications. The Chi number provides confirmation of the first assumption, based on proximity of blocknots in most cases.
Notes
References
Cryptography
Ciphers | Blocknots | [
"Mathematics",
"Engineering"
] | 1,491 | [
"Applied mathematics",
"Cryptography",
"Cybersecurity engineering"
] |
56,442,229 | https://en.wikipedia.org/wiki/Vladimir%20Alekseev%20%28mathematician%29 | Vladimir Mikhailovich Alekseev (Владимир Михайлович Алексеев, sometimes transliterated as "Alexeyev" or "Alexeev", 17 June 1932, Bykovo, Ramensky District, Moscow Oblast – 1 December 1980) was a Russian mathematician who specialized in celestial mechanics and dynamical systems.
He attended secondary school in Moscow at one of the special schools of mathematics affiliated with Moscow State University and participated in several mathematical olympiads. From 1950 he studied at the Faculty of Mathematics and Mechanics at the Moscow State University, where he worked as a student of Andrei Kolmogorov on the asymptotic behavior in the three-body problem of celestial mechanics. Already as an undergraduate, Alekseev proved significant new results on quasi-random motion associated with the three-body problem. This was the subject of his dissertation for the Russian candidate degree (Ph.D.) and then his dissertation in 1969 for the Russian doctorate (higher doctoral degree). From 1957 he taught at Moscow State University.
In 1970 Alekseev was an Invited Speaker with talk Sur l´allure finale du mouvement dans le problème de trois corps at the ICM in Nice.
Over a 20-year period, he conducted 3 ongoing seminars: with Yakov Sinai on dynamical systems, with V. A. Egorov on celestial mechanics, and with M. Zelikin and V. M. Tikhomirov on variational problems and optimal control.
Selected publications
Symbolic dynamics (Russian), Kiev 1976
with V. M. Tikhomirov, S. Fomin: Optimal Control, New York: Consultants Bureau 1987 (trans. from the Russian by V. M. Volosov)
"A theorem on an integral inequality and some of its applications" by V. M. Alekseev in Thirteen papers on dynamical systems by V. M. Alekseev & 14 other authors, American Mathematical Society 1981
with E. M. Galeev, V. M. Tikhomirov: Recueil de problèmes d'optimisation (French), Moscow, MIR 1987
References
External links
Mathnet.ru
20th-century Russian mathematicians
Dynamical systems theorists
Russian systems scientists
Moscow State University alumni
Academic staff of Moscow State University
1932 births
1980 deaths | Vladimir Alekseev (mathematician) | [
"Mathematics"
] | 485 | [
"Dynamical systems theorists",
"Dynamical systems"
] |
56,446,596 | https://en.wikipedia.org/wiki/AIDS%20Research%20and%20Therapy | AIDS Research and Therapy is a peer-reviewed open access medical journal covering research on HIV/AIDS. It was established in 2004 and is published by BioMed Central. The editors-in-chief are Eric Arts (University of Western Ontario) and Mark Boyd (Kirby Institute). According to the Journal Citation Reports, the journal has a 2017 impact factor of 2.357.
References
External links
Academic journals established in 2004
BioMed Central academic journals
HIV/AIDS journals
English-language journals | AIDS Research and Therapy | [
"Biology"
] | 98 | [
"Virus stubs",
"Viruses"
] |
56,446,915 | https://en.wikipedia.org/wiki/Lamb%20surface | In fluid dynamics, Lamb surfaces are smooth, connected orientable two-dimensional surfaces, which are simultaneously stream-surfaces and vortex surfaces, named after the physicist Horace Lamb. Lamb surfaces are orthogonal to the Lamb vector everywhere, where and are the vorticity and velocity field, respectively. The necessary and sufficient condition are
Flows with Lamb surfaces are neither irrotational nor Beltrami. But the generalized Beltrami flows has Lamb surfaces.
See also
Beltrami flow
References
Fluid dynamics | Lamb surface | [
"Chemistry",
"Engineering"
] | 100 | [
"Piping",
"Chemical engineering",
"Fluid dynamics"
] |
56,447,040 | https://en.wikipedia.org/wiki/Lamb%20vector | In fluid dynamics, Lamb vector is the cross product of vorticity vector and velocity vector of the flow field, named after the physicist Horace Lamb. The Lamb vector is defined as
where is the velocity field and is the vorticity field of the flow. It appears in the Navier–Stokes equations through the material derivative term, specifically via convective acceleration term,
In irrotational flows, the Lamb vector is zero, so does in Beltrami flows. The concept of Lamb vector is widely used in turbulent flows. The Lamb vector is analogous to electric field, when the Navier–Stokes equation is compared with Maxwell's equations.
Gromeka–Lamb equation
The Euler equations written in terms of the Lamb vector is referred to as the Gromeka–Lamb equation, named after Ippolit S. Gromeka and Horace Lamb. This is given by
Properties of Lamb vector
The divergence of the lamb vector can be derived from vector identities,
At the same time, the divergence can also be obtained from Navier–Stokes equation by taking its divergence. In particular, for incompressible flow, where , with body forces given by , the Lamb vector divergence reduces to
where
In regions where , there is tendency for to accumulate there and vice versa.
References
Fluid dynamics
Vector calculus | Lamb vector | [
"Chemistry",
"Engineering"
] | 269 | [
"Piping",
"Chemical engineering",
"Fluid dynamics"
] |
56,447,389 | https://en.wikipedia.org/wiki/IEC%2061360 | IEC 61360, with the title "Standard data element types with associated classification scheme", is a series of standard documents defining a general purpose vocabulary in terms of a reference dictionary published by the International Electrotechnical Commission.
Intended use
The vocabulary specified in IEC 61360 may be used to define ontologies for use in the field of electrotechnology, electronics and related domains.
Structure
The IEC 61360 series is structured into different parts:
IEC 61360-1 - Part 1: Definitions - Principles and methods
IEC 61360-2 - Part 2: EXPRESS dictionary schema
IEC 61360-4 - Part 4: IEC Common Data Dictionary (IEC CDD)
IEC 61360-6 - Part 6: IEC Common Data Dictionary (IEC CDD) quality guidelines
IEC 61360-1 provides a detailed introduction to the structure of the dictionary and its use.
IEC 61360-2 specifies the detailed dictionary data model and IEC 61360-6 stipulates quality criteria for the content of the dictionary.
The data model defined in IEC 61360-2 is also published in ISO 13584-42.
The IEC provides a technical dictionary for the use in the electro-technical and electronic domain which is published as IEC 61360-4. This dictionary is called IEC Common Data Dictionary (IEC CDD) and can be accessed as a web page (https://cdd.iec.ch).
See also
IEC 61360 also defines the base for other product taxonomies like eCl@ss.
Industrie 4.0 uses product property description based on IEC 61360.
References
61360 | IEC 61360 | [
"Technology"
] | 339 | [
"Computer standards",
"IEC standards"
] |
56,449,548 | https://en.wikipedia.org/wiki/Cosmos%20%28standard%29 | COSMOS stands for "COSMetic Organic and Natural Standard", which sets certification requirements for organic and natural cosmetics products in the Europe. The standard is recognized globally by the cosmetic industry. By adhering to specific guidelines, cosmetics marketers can use COSMOS signatures, which are registered trademarks, on packaging to confirm the products meet minimum industry requirements to be considered organic or natural.
History
In 2002 five European organisations responsible for setting organic and natural cosmetics standards met at a trade show to share ideas for broader standards to be used globally. These five COSMOS members are:
BDIH (Germany)
Cosmebio (France)
Ecocert Greenlife SAS (France)
ICEA (Italy)
Soil Association (Great Britain)
Over 1,600 manufacturers who sell over 25,000 products across over 45 countries follow the standard, according to Cosmos-standard.org. About 85% of the certified cosmetics industry uses COSMOS signatures on its products.
Although the five members differed on certain standards separately, they were able to smooth out differences to create a harmonised international standard that was first published in 2010. At this time the five members formed a non-profit international association overseeing the standard. In June 2010 the COSMOS-standard AISBL was awarded Royal Assent from Belgian authorities. The documents published with the standard include:
The Control Manual: describes how the control systems works
The Labeling Rules: explains how to use COSMOS labels
The Technical Guide: additional information
Certification and Labeling Process
There are four main certification signatures that comprise the COSMOS-standard, which are for ORGANIC, NATURAL, COSMOS CERTIFIED and COSMOS APPROVED products. Here are six steps to gaining approval of product labeling within the certification process:
The authorized COSMOS-standard certification body must first approve of the product specification.
The applicant must submit their proposed product labeling to the certification body and await approval. Generic label designs for certain single-ingredient product are acceptable if the design is consistent for all products.
In the event the product specification is not approved first, the labeling can only get provisional approval.
Only after full approval of the labeling is granted by the certification body can the manufacturer print the labelling. The certification process must be completed before the labels can be used commercially.
If the manufacturer needs to make changes to the product or labeling after gaining certification, they must notify the certification body and wait for written approval or a certificate update. Further approval from the certification body will be needed if the manufacturer makes changes to the organic percentage of the ingredients. The vendor will also have to make an amendment to the ingredients.
Before the product can be launched, the labeling must be approved by the certification body and the product must be listed on the COSMOS-standard certificate. Printing labels without first getting approval can lead to certification withdrawal if the certification body determines the products and labels are non-compliant.
Basic Labeling Requirements
Manufacturers and marketers are only allowed to use COSMOS terms and signatures for products authorized by the certification body. The certification body must be identified on product labels if it is not clearly mentioned anywhere else on the product. In cases in which the label size restricts product labeling, the certification body may allow flexibility as long as the product maintains the general principles of the Labeling Guide. The firm must at least mention the nature of the certification (such as organic or natural) and the identity of the certification body.
Product Identification
Marketers are allowed to use the COSMOS terms and signatures on company letterhead and websites under certain conditions. All the products of a brand must be certified organic in order for the company to make the claim they are "COSMOS ORGANIC certified." Otherwise, the firm must be clear that only specific products have been certified organic. In other words, the use of the terms and signatures must not be misleading to the consumer.
Essentially, the labelling must clearly and accurately describe the product, which must comply with the standard. The marketer must avoid listing ingredients or naming the product in a way that implies it contains certain ingredients that are not present. Any use or branding of the term "organic," for example, must comply with the organic standard and not be confusing to the consumer.
The labeling must not confuse the terms "organic" and "natural," which have separate definitions and certifications based on the way the products and ingredients are processed. If a brand sells several organic products and a few natural products, they must make it clear in their labeling and marketing the differences. The firm must also be clear if some of its products have no certification at all. In other words, in order for a company to promote itself as "COSMOS ORGANIC certified," its entire range of products must meet the organic standard and be certified.
Companies are not allowed to use logos or seals that may mislead customers into believing the products are COSMOS certified.
References
External links
List of certified products
www.http://eur-lex.europa.eu/cosmetics
https://www.fda.gov/Cosmetics/GuidanceRegulation
BDIH (Germany)
Cosmebio (France)
Ecocert Greenlife SAS (France)
ICEA (Italy)
Soil Association (Great Britain)
ETKO (Türkiye)
Technical specifications
Perfumery
Cosmetics
Toiletry
Perfumes
Packaging
Processes | Cosmos (standard) | [
"Technology"
] | 1,043 | [
"nan"
] |
56,449,950 | https://en.wikipedia.org/wiki/Biomaterials%20Science | Biomaterials Science is a peer-reviewed scientific journal that explores the underlying science behind the function, interactions and design of biomaterials. It is published by the Royal Society of Chemistry. The current editor-in-chief is Jianjun Cheng (Westlake University, China), while the executive editor is Maria Southall.
The journal was established in 2013 and since January 2018 has been the official journal of the European Society for Biomaterials. Since the start of 2016 the journal has been online only. It publishes primary research (Communications and full paper articles) and review-type articles (reviews and minireviews).
Abstracting and indexing
The journal is abstracted and indexed in:
Science Citation Index
Index Medicus/MEDLINE/PubMed
Scopus
See also
List of scientific journals in chemistry
Journal of Materials Chemistry B
MedChemComm
References
External links
Materials science journals
Royal Society of Chemistry academic journals
Biochemistry journals
Academic journals established in 2013
Monthly journals
English-language journals | Biomaterials Science | [
"Chemistry",
"Materials_science",
"Engineering"
] | 203 | [
"Biochemistry journals",
"Biochemistry literature",
"Materials science journals",
"Materials science"
] |
56,451,179 | https://en.wikipedia.org/wiki/NGC%206044 | NGC 6044 is a lenticular galaxy located about 465 million light-years away in the constellation Hercules. NGC 6044 was discovered by astronomer Lewis Swift on June 27, 1886. It was then rediscovered by astronomer Guillaume Bigourdan on June 8, 1888. NGC 6044 is a member of the Hercules Cluster.
See also
List of NGC objects (6001–7000)
NGC 6039
References
External links
Hercules (constellation)
Lenticular galaxies
6044
IC objects
057015
Astronomical objects discovered in 1886
Hercules Cluster
Discoveries by Lewis Swift | NGC 6044 | [
"Astronomy"
] | 110 | [
"Hercules (constellation)",
"Constellations"
] |
56,451,303 | https://en.wikipedia.org/wiki/Rhetoric%20of%20technology | The rhetoric of technology is both an object and field of study. It refers to the ways in which makers and consumers of technology talk about and make decisions regarding technology and also the influence that technology has on discourse. Studies of the rhetoric of technology are interdisciplinary. Scholars in communication, media ecology, and science studies research the rhetoric of technology. Technical communication scholars are also concerned with the rhetoric of technology.
The phrase "rhetoric of technology" gained prominence with rhetoricians in the 1970s, and the study developed in conjunction with interest in the rhetoric of science. However, scholars have worked to maintain a distinction between the two fields. Rhetoric of technology criticism addresses several issues related to technology and employs many concepts, including several from the canon of classical rhetoric, for example ethos, but the field has also adopted contemporary approaches, such as new materialism.
Definition
While the definition and scope of rhetoric is contested, scholars in the discipline, or rhetoricians, study the capacity of symbols to create change and influence perspectives. Often, rhetoricians study discourse and texts, but they also study objects. Technology is both techniques and objects that embody and enact techniques. Thus, rhetoric of technology scholars may look at texts and discourse associated with technology or techniques and technological objects. Concerns of rhetoric of technology include the influence of technology on public deliberation, conceptions of the self, and how new technologies come to be developed and adopted.
Scholars who study rhetoric of technology have argued that it should be treated as distinct from the rhetoric of science. Charles Bazerman offers three distinctions between rhetoric of technology and rhetoric of science. First, unlike science, technology has always been intertwined with other clearly rhetorical endeavors, such as commerce and finance. Second, while the discourse of science often works towards specialization, the discourse of technology is pervasive. We may not all conduct experiments, but we all interact with and operate technology. Lastly, the products of technology are mostly material while the products of science are mostly symbols. Carolyn Miller argues that rhetoric of science must be treated as distinct from rhetoric of technology because technology and science differ in motivation, criteria of judgment, and values.
History
Scholars started to suggest the importance of studying rhetoric of technology in the 1970s alongside a growing interest in rhetoric of science. Thomas W. Benson and Gerard A. Hauser referred to the "rhetoric of technology" in a book review published in 1973 and noted the shared concern of rhetoric and technology with technique. In 1978 Carolyn Miller wrote “Technology as a Form of Consciousness: A Study of Contemporary Ethos.” In addition to explaining why rhetoric of technology should be treated separately from science, Miller argues that technology gives rise to a particular ethos, or personal character, because it generates particular actions and a particular consciousness. She concludes that technological consciousness assumes an objective perspective that erodes ethos. Within technological consciousness, actions are right or wrong regardless of cultural possibilities because assessments are assumed to be objective.
In a series of oral histories collected by the Association for the Rhetoric of Science, Technology, and Medicine, scholars familiar with both fields recognized that there has been more research addressing the rhetoric of science than comparable work on technology. Carolyn Miller suggested that one reason for the relative lack of rhetoric of technology scholarship is that it is harder to find relevant texts to analyze. Miller noted that many of the primary texts dealing with technology are private company documents.
Concepts
Materialism and New Materialism
In 1980 Langdon Winner wrote the article “Do Artifacts Have Politics?” Winner suggests that objects reflect and enact ideological perspectives. Winner's idea shares much in common with a materialist approach to rhetoric of technology. Materialist approaches to rhetoric of technology are related to materialism and treat technological objects the same as they may treat a text by critiquing how objects persuade and influence.
Jeremy Packer and Stephen B. Wiley provide an overview of new materialist approaches to rhetoric in their book Communication Matters: Materialist Approaches to Media. Packer and Wiley conceptualize materiality as a “corrective” to the concept of communication as intangible. They suggest that the corrective is in response to a “poststructuralist impasse” in the field of communication, rhetoric, and media studies. They outline two approaches to materiality: 1) to equate materiality with physicality and approach infrastructure, body, space, and technology as fields of communication and 2) to analyze the materiality of communication itself, the physiological, mechanical, or digital media of communication. Packer and Wiley also identify key themes that are explored in materialist approaches: economy, discourse, technology, space, and bodies.
Ethos
In her 1978 article “Technology as a Form of Consciousness: A Study of Contemporary Ethos,” Carolyn Miller argued that technology was fundamentally changing how individuals judge personal character. She suggested that the ultimate result of a technological consciousness would be to erode a concern with ethos as technology would prevail in presenting actions and decision as objectively right or wrong. If all decisions are objective, then there is no longer a need for judgments of character. In a 1992 article, Steven B. Katz employed Miller's "technological consciousness" to help explain the rhetoric used by members of the Nazi regime to enact the Holocaust. In 2004, Miller revisited the relationship between ethos and technology in an exploration of the impact of human-computer interaction. She explores two modes of human-computer interaction: expert systems versus intelligent agents. She argues that in both modes of interaction subjectivity blurs between the human-user and the computer, creating a hybrid (borrowing from Bruno Latour) or cyborg (borrowing from Donna Haraway). Expert systems are designed to mimic human experts; they typically draw from a deep database of information. Intelligent agent computer systems, in contrast, learn from interacting with an environment. The merger between human and computer destabilizes ethos according to Miller. As the intelligent agent model of computing has grown in popularity, Miller suggests that there has been a shift from a logos-centric to a pathos-centric ethos. Neither, she contends, provide ethics, or arete, which is a gap that rhetoric should fill.
Invention
As invention is important to the development of new technology, invention is also important to rhetoric. Along with arrangement, delivery, style, and memory, invention is one of the five canons of rhetoric, or the five key elements of a competent speech according to classic rhetorical theory. Therefore, some rhetoricians argue that the development of new technology is fundamentally rhetorical. John A. Lynch and William J. Kinsella describe how both technology and rhetoric are both concerned with creating something new from available resources and know-how.
Kairos
Kairos is an ancient Greek word that captures the idea that there is a right time for action. Carolyn Miller has suggested that the "right time" is also a central concern for technology. She uses the Japanese "Fifth Generation" computer project as a case study. Miller contends that within technological discourse kairos is both a powerful theme and useful tool of analysis. She supports her claim with an analysis of technological forecasting, which was a central feature of the Japanese computer project, and concludes that technologists employ kairos to justify investment in particular technologies.
References
Bibliography
Bazerman, Charles. The Languages of Edison's Light. Inside Technology. Cambridge, Mass.: MIT Press, 1999.
Durack, Katherine T. “Gender, Technology, and the History of Technical Communication.” Technical Communication Quarterly 6, no. 3. (1997): 249–260. https://doi.org/10.1207/s15427625tcq0603_2.
Lynch, John A. and William J. Kinsella. “The Rhetoric of Technology as a Rhetorical Technology.” Poroi 9, Iss. 1 (2013): Article 13. http://dx.doi.org/10.13008/2151-2957.1152.
Miller, Carolyn. “Technology as a Form of Consciousness: A Study of Contemporary Ethos.” Central States Speech Journal 29, no. 4 (1978): 228–236. https://doi.org/10.1080/10510977809367983.
Miller, Carolyn. “Expertise and Agency: Transformations of Ethos in Human-Computer Interaction.” In The Ethos of Rhetoric. Edited by Michael J. Hyde, 197–218. Columbia: University of South Carolina Press, 2004.
Packer, Jeremy, and Stephen B. Crofts Wiley. “Introduction: The Materiality of Communication.” In Communication Matters: Materialist Approaches to Media, Mobility and Networks. Edited by Jeremy Packer and Stephen B. Crofts Wiley, 3–16. New York: Routledge, 2012.
Wallace, Karl Richards, Speech Communication Association, and National Conference on Rhetoric National Conference on Rhetoric (1970 : St. Charles, Ill.). The Prospect of Rhetoric: Report of the National Developmental Project, Sponsored by Speech Communication Association. Edited by Lloyd F Bitzer and Edwin Black. Prentice-Hall Speech Communication Series. Englewood Cliffs, N.J: Prentice-Hall, 1971.
Winner, Langdon. “Do Artifacts Have Politics?” Daedalus, 109, no. 1, Modern Technology: Problem or Opportunity? (Winter, 1980): 121-136
Technology
Philosophy of technology | Rhetoric of technology | [
"Technology"
] | 1,913 | [
"Philosophy of technology",
"Science and technology studies"
] |
56,452,622 | https://en.wikipedia.org/wiki/Horst%20Herrlich | Horst Herrlich (11 September 1937, in Berlin – 13 March 2015, in Bremen) was a German mathematician, known as a pioneer of categorical topology.
Education and career
Horst Herrlich received his PhD in 1962 with thesis Ordnungsfähigkeit topologischer Räume (Orderability of topological spaces) under Karl Peter Grotemeyer and Alexander Dinghas at the Free University of Berlin, where he also received his habilitation in 1965 with a thesis on E-compact spaces (introduced by Stanisław Mrówka in 1958).
From 1971 to 2002 Herrlich was a professor of mathematics with a focus on general topology and category theory at the University of Bremen. He was part of the editorial staff for the third volume Deskriptive Mengenlehre und Topologie of the collected works of Felix Hausdorff.
He was an Invited Speaker of the International Congress of Mathematicians in 1974 in Vancouver. He is regarded as a founder of categorical topology, which deals with general topology using the methods of category theory.
Selected publications
with George E. Strecker:
with Jiří Adámek and George E. Strecker:
References
20th-century German mathematicians
21st-century German mathematicians
Free University of Berlin alumni
Academic staff of the University of Bremen
1937 births
2015 deaths
Topologists
Category theorists | Horst Herrlich | [
"Mathematics"
] | 266 | [
"Mathematical structures",
"Topologists",
"Topology",
"Category theory",
"Category theorists"
] |
56,452,655 | https://en.wikipedia.org/wiki/EASA%20%28software%29 | EASA is a low-code development platform which enables “citizen developers” to web-enable existing tools created with Excel, MATLAB, Python, R and other software. Custom web apps created with EASA are intended for minimizing or eliminating development time by re-using the original existing tools as the engine of the app.
History
EASA has OFFICES in Oxford, UK, and Pittsburgh, Pennsylvania.
In 2002, EASA 1.0 was released as an engineering design tool and first customers started to go live with the platform. In the same year, the United States Patent was granted while the UK patent US6430609B1 was granted in 2003.
In 2004; P&G became the first enterprise customer.
As of 2005, EASA has an Excel interface for direct links between an EASA application and spreadsheets. The Excel specific capability enables a wide range of industries to employ EASA, including financial, insurance, pharmaceutical, logistics and manufacturing.
On July 15, 2022, EASA was acquired by Volaris Group, one of six operating groups of Constellation Software Inc. CSI is a leading worldwide provider of software and related services, with revenues exceeding $5 billion, and is listed on the Toronto Stock Exchange under the symbol "CSU". The full press release can be found here.
Product and services
EASA software enables “citizen developers” to create fit-for-purpose web apps.
See also
AEA Technology
Volaris Group
Constellation Software, Inc.
Platform as a Service
References
External links
Software distribution platforms
Computing platforms | EASA (software) | [
"Technology"
] | 314 | [
"Computing platforms"
] |
56,452,747 | https://en.wikipedia.org/wiki/Cryogenic%20electron%20microscopy | Cryogenic electron microscopy (cryo-EM) is a cryomicroscopy technique applied on samples cooled to cryogenic temperatures. For biological specimens, the structure is preserved by embedding in an environment of vitreous ice. An aqueous sample solution is applied to a grid-mesh and plunge-frozen in liquid ethane or a mixture of liquid ethane and propane. While development of the technique began in the 1970s, recent advances in detector technology and software algorithms have allowed for the determination of biomolecular structures at near-atomic resolution. This has attracted wide attention to the approach as an alternative to X-ray crystallography or NMR spectroscopy for macromolecular structure determination without the need for crystallization.
In 2017, the Nobel Prize in Chemistry was awarded to Jacques Dubochet, Joachim Frank, and Richard Henderson "for developing cryo-electron microscopy for the high-resolution structure determination of biomolecules in solution." Nature Methods also named cryo-EM as the "Method of the Year" in 2015.
History
Early development
In the 1960s, the use of transmission electron microscopy for structure determination methods was limited because of the radiation damage due to high energy electron beams. Scientists hypothesized that examining specimens at low temperatures would reduce beam-induced radiation damage. Both liquid helium (−269 °C or 4 K or −452.2 °F) and liquid nitrogen (−195.79 °C or 77 K or −320 °F) were considered as cryogens. In 1980, Erwin Knapek and Jacques Dubochet published comments on beam damage at cryogenic temperatures sharing observations that:
Thin crystals mounted on carbon film were found to be from 30 to 300 times more beam-resistant at 4 K than at room temperature... Most of our results can be explained by assuming that cryoprotection in the region of 4 K is strongly dependent on the temperature.
However, these results were not reproducible and amendments were published in Nature just two years later informing that the beam resistance was less significant than initially anticipated. The protection gained at 4 K was closer to "tenfold for standard samples of L-valine", than what was previously stated.
In 1981, Alasdair McDowall and Jacques Dubochet, scientists at the European Molecular Biology Laboratory, reported the first successful implementation of cryo-EM. McDowall and Dubochet vitrified pure water in a thin film by spraying it onto a hydrophilic carbon film that was rapidly plunged into cryogen (liquid propane or liquid ethane cooled to 77 K). The thin layer of amorphous ice was less than 1 μm thick and an electron diffraction pattern confirmed the presence of amorphous/vitreous ice. In 1984, Dubochet's group demonstrated the power of cryo-EM in structural biology with analysis of vitrified adenovirus type 2, T4 bacteriophage, Semliki Forest virus, Bacteriophage CbK, and Vesicular-Stomatitis-Virus.
Recent advancements
The 2010s were marked with drastic advancements of electron cameras. Notably, the improvements made to direct electron detectors have led to a "resolution revolution" pushing the resolution barrier beneath the crucial ~2-3 Å limit to resolve amino acid position and orientation.Henderson (MRC Laboratory of Molecular Biology, Cambridge, UK) formed a consortium with engineers at the Rutherford Appleton Laboratory and scientists at the Max Planck Society to fund and develop a first prototype. The consortium then joined forces with the electron microscope manufacturer FEI to roll out and market the new design. At about the same time, Gatan Inc. of Pleasanton, California came out with a similar detector designed by Peter Denes (Lawrence Berkeley National Laboratory) and David Agard (University of California, San Francisco). A third type of camera was developed by Nguyen-Huu Xuong at the Direct Electron company (San Diego, California).More recently, advancements in the use of protein-based imaging scaffolds are helping to solve the problems of sample orientation bias and size limit. Proteins smaller than ~50 kDa generally have too low a signal-to-noise ratio (SNR) to be able to resolve protein particles in the image, making 3D reconstruction difficult or impossible. The SNR of smaller proteins can be improved by binding them to an imaging scaffold. The Yeates group at UCLA was able to create a clearer image of three variants of KRAS (roughly 19 kDa in size) by utilising a rigid imaging scaffold, and using DARPins as modular binding domains between the scaffold and the protein of interest.
2017 Nobel Prize in Chemistry
In recognition of the impact cryo-EM has had on biochemistry, three scientists, Jacques Dubochet, Joachim Frank and Richard Henderson, were awarded the Nobel Prize in Chemistry "for developing cryo-electron microscopy for the high-resolution structure determination of biomolecules in solution."
Comparisons to X-ray crystallography
Traditionally, X-ray crystallography has been the most popular technique for determining the 3D structures of biological molecules. However, the aforementioned improvements in cryo-EM have increased its popularity as a tool for examining the details of biological molecules. Since 2010, yearly cryo-EM structure deposits have outpaced X-ray crystallography. Though X-ray crystallography has drastically more total deposits due to a decades-longer history, total deposits of the two methods are projected to eclipse around 2035.
The resolution of X-ray crystallography is limited by crystal homogeneity, and coaxing biological molecules with unknown ideal crystallization conditions into a crystalline state can be very time-consuming, in extreme cases taking months or even years. To contrast, sample preparation in cryo-EM may require several rounds of screening and optimization to overcome issues such as protein aggregation and preferred orientations, but it does not require the sample to form a crystal, rather samples for cryo-EM are flash-frozen and examined in their near-native states.
According to Proteopedia, the median resolution achieved by X-ray crystallography (as of May 19, 2019) on the Protein Data Bank is 2.05 Å, and the highest resolution achieved on record (as of September 30, 2022) is 0.48 Å. As of 2020, the majority of the protein structures determined by cryo-EM are at a lower resolution of 3–4 Å. However, as of 2020, the best cryo-EM resolution has been recorded at 1.22 Å, making it a competitor in resolution in some cases.
Correlative light cryo-TEM and cryo-ET
In 2019, correlative light cryo-TEM and cryo-ET were used to observe tunnelling nanotubes (TNTs) in neuronal cells.
Scanning electron cryomicroscopy
Scanning electron cryomicroscopy (cryoSEM) is a scanning electron microscopy technique with a scanning electron microscope's cold stage in a cryogenic chamber.
Cryogenic transmission electron microscopy
Cryogenic transmission electron microscopy (cryo-TEM) is a transmission electron microscopy technique that is used in structural biology and materials science. Colloquially, the term "cryogenic electron microscopy" or its shortening "cryo-EM" refers to cryogenic transmission electron microscopy by default, as the vast majority of cryo-EM is done in transmission electron microscopes, rather than scanning electron microscopes.
Centers
The Federal Institute of Technology, the University of Lausanne and the University of Geneva opened the Dubochet Center For Imaging (DCI) at the end of November 2021, for the purposes of applying and further developing cryo-EM. Less than a month after the first identification of the SARS-CoV-2 Omicron variant, researchers at the DCI were able to define its structure, identify the crucial mutations to circumvent individual vaccines and provide insights for new therapeutic approaches.
The Danish National cryo-EM Facility also known as EMBION was inaugurated on December 1, 2016. EMBION is a cryo-EM consortium between Danish Universities (Aarhus University host and University of Copenhagen co-host).
Advanced methods
Cryogenic electron tomography (cryo-ET), a specialized application where many images are taken of individual samples at various tilt angles, resulting in a 3D reconstruction of a single sample.
Electron crystallography, method to determine the arrangement of atoms in solids using a TEM
MicroED, method to determine the structure of proteins, peptides, organic molecules, and inorganic compounds using electron diffraction from 3D crystals
Single particle analysis cryo-EM, an averaging method to determine protein structure from monodisperse samples.
See also
Cryofixation
Cryo bio-crystallography
Electron tomography (ET)
References
Electron microscopy techniques
Cell biology
Protein structure
Scientific techniques | Cryogenic electron microscopy | [
"Chemistry",
"Biology"
] | 1,834 | [
"Protein structure",
"Cell biology",
"Structural biology"
] |
56,452,940 | https://en.wikipedia.org/wiki/Mozilla%20Open%20Software%20Patent%20License | The Mozilla Open Software Patent License (MOSPL) is a permissive patent license developed and maintained by the Mozilla Foundation.
References
Software patent law
Intellectual property activism | Mozilla Open Software Patent License | [
"Technology"
] | 38 | [
"Computing stubs",
"Software stubs"
] |
73,532,092 | https://en.wikipedia.org/wiki/Lewis%20Tunnicliffe | Lewis Tunnicliffe is an Atlanta-based product design and development manager at Birla Carbon, who has been recognized internationally for his scientific research in the area of carbon black filler applications to elastomers.
Early life
Tunnicliffe is originally from the West Midlands in Staffordshire, England and grew up in the small village of Haughton.
Education
Tunnicliffe earned a BS in chemistry at the University of Durham in 2005. He then worked in industry for three years, returning to graduate school and completing a Ph.D. in 2015 at Queen Mary University of London under advisors James Busfield and Alan G. Thomas.
Career
Tunnicliffe's first position following his undergraduate degree was with Sibelco Europe as a research scientist. He joined Birla Carbon in February 2016 as a materials scientist. He currently heads a product design and development group at Birla. Tunnicliffe won a grant from USDA to investigate the application of cellulose nanoparticles in tires.
His most cited academic work produced a method for simultaneous dielectric/dynamic mechanical characterization of a filled elastomer. The technique produces information about the presence of dipoles on the polymer-filler interface, useful in understanding origins of the Mullins and Payne effects. He has also characterized the size distribution of crack precursors in carbon black filled rubber.
Awards and recognition
2011 - James S. Walker award from Institute of Materials, Minerals and Mining
2013 - Best Young Scientist award from Tire Technology International.
2023 - Sparks–Thomas award from the ACS Rubber Division.
References
Polymer scientists and engineers
Living people
Year of birth missing (living people)
Alumni of Queen Mary University of London | Lewis Tunnicliffe | [
"Chemistry",
"Materials_science"
] | 341 | [
"Polymer scientists and engineers",
"Physical chemists",
"Polymer chemistry"
] |
73,532,723 | https://en.wikipedia.org/wiki/Ultrasound-triggered%20drug%20delivery%20using%20stimuli-responsive%20hydrogels | Ultrasound-triggered drug delivery using stimuli-responsive hydrogels refers to the process of using ultrasound energy for inducing drug release from hydrogels that are sensitive to acoustic stimuli. This method of approach is one of many stimuli-responsive drug delivery-based systems that has gained traction in recent years due to its demonstration of localization and specificity of disease treatment. Although recent developments in this field highlight its potential in treating certain diseases such as COVID-19, there remain many major challenges that need to be addressed and overcome before more related biomedical applications are clinically translated into standard of care.
Types of Hydrogels Used in Drug Delivery Systems
Traditional Hydrogels
Hydrogels are three dimensional structures consisting of hydrophilic polymers (i.e., polymers, colloids, etc.) that form networks through cross-linking processes. The macromolecules involved in the formation of hydrogels are able to absorb and retain large amounts of water and other aqueous substances. Since its discovery in 1960, hydrogels have become a crucial component in biomedical research and applications. A few examples of hydrogel use include organ regeneration, wound healing, and drug delivery. Hydrogels are generally classified based on the following characteristics: material, crosslinking mechanism, physical structure, electric charge, and response to stimuli. Synthesis of hydrogels are developed from a combination or isolated forms of natural and synthetic polymers. The main examples of natural polymers used to derive hydrogels include polysaccharides, polypeptides, and polynucleotides. Several known examples of synthetic polymeric constituents include poly (vinyl alcohol) (PVA), poly (acrylic acid) (PAA), and poly (2-hydroxyethyl methacrylate) (PHEMA). The crosslinking mechanism of the hydrophilic macromolecules are driven by covalent bonding, resulting in a physical- or chemical-type hydrogel. Physical hydrogels contain reversible matrices of hydrogen and non-covalent bonds, while chemical hydrogels are composed of irreversible matrices that are molecularly held together by covalent bonds. Used as another parameter in characterizing gels, electric charge (also referred to as ionic character) describes the ability of the macromolecules to drive swelling behavior. Hydrogels classified based on this property fall under three main categories: cationic, anionic, and amphoteric. Bawa et al. demonstrated that cationic gels swell in acidic environments but remain condensed in basic environments.
Smart Hydrogel Polymers
Since traditional hydrogels were able to encapsulate and carry materials, research into drug-loaded hydrogels began to expand in the field of drug delivery. Dubbed as “smart hydrogels” or “stimuli-responsive hydrogels”, these gels are able to dynamically respond to external or internal stimuli in addition to possessing similar swelling-deswelling properties of traditional hydrogels. Various examples of external stimuli that have been used to control smart hydrogels in drug delivery systems include temperature, pH, light, ultrasound, and enzymes. Additional considerations in designing smart hydrogels involve fundamental understanding of bond strength, molecular weight, degree of polymerization, polymer structure, and molecular assembly. The bond strength describes the cross-linking strength of the hydrogel, which is considered in designing drug release mechanisms of hydrogel-based platforms. Scientific understanding of the molecular weight of gels is taken into account when loading drugs of increasing weight. Similar to conventional hydrogels, the polymeric chain (or backbone) of the smart hydrogels is derived from polysaccharides, polypeptides, and polynucleotides. Examples of natural polymers include alginate, chitosan, cellulose, gelatin, fibrin, and collagen. Hydrogel size and type are the two main properties considered in designing hydrogels when seeking the optimal delivery route for drug administration. Various examples of hydrogel type designs include nanoparticles, nanogels, and microgels. For example, El-Sherbiny et al. proposed gelatin-based hydrogel nanoparticles that were stimulated by magnetic forces. Other variables considered in hydrogel design include safety, biodegradability, drug loading capacity, and on-demand control of drug release [23]. The main safety concerns in formulating hydrogels include bacterial infection and biocompatibility. The final parameter considered in developing hydrogels for drug delivery systems revolve around the embedded payload within the hydrogel. Cells, proteins, and therapeutic drugs are the main payloads used in hydrogel-based drug delivery platforms. In one example of payload use, Jiang et al. demonstrated the stimulated release of gallic acid from chitin-based hydrogel via ultrasound induction.
Use of Ultrasound for Drug Therapy
General Overview of Ultrasound
According to the Moyano et al., ultrasound refers to vibrational mechanical waves with frequencies greater than 20 kilohertz (kHz). Ultrasound is traditionally used for imaging, monitoring, and diagnosing a broad range of conditions in the medical field. Various examples of ultrasound modalities include Doppler ultrasound, focused ultrasound, and echocardiography. The key component of using most ultrasound devices is a transducer that consists of an array of piezoelectric crystals. The atoms within these crystals vibrate under electrical current stimulation, converting this electrical energy into mechanical, in this case, high acoustic or ultrasonic energy. When the sonicating transducer is directed at the human body, the resulting sound pressure waves produced by the transducer will pass through the dermal layer and reach the tissue where the waves are reflected (or echoed) back to the transducer and converted back into electrical signals for image reconstruction. Tissue characteristics such as density affect the intensity of the reflected sound waves. Other parameters such as beam frequency, equipment components, and imaging settings contribute towards the resolution of the ultrasound application. Ultrasound has also been used for therapeutic purposes because it is non-invasiveness, able to provide deeper tissue penetration, and safely localize application of acoustic energy.
While ultrasound modalities are generally considered safe, extreme levels of human exposure to ultrasound can increase injury risk. In the US, the Food and Drug Administration (FDA) guidelines, the maximum allowed exposure to ultrasound for use is defined by the following key parameters: mechanical index, thermal index, spatial-peak temporal-peak intensity, spatial-peak pulse-average power, and spatial-peak temporal-average power. Mechanical index (MI) is a unitless metric that is used to measure the acoustic power output from ultrasound use. Since the MI is inversely proportional to the ultrasonic beam frequency, the MI will be lower at higher frequencies. The thermal index (TI) describes the risk of increasing the temperature of the tissue being sonicated by ultrasound. A solution to decreasing TI involves the reduction of the time that the sonicating transducer is focused on the targeted area. The spatial-peak temporal-peak (SPTP) power refers to the highest intensity output of the ultrasound beam during implementation. The spatial-peak pulse-average (SPPA) power is a measure of the maximum intensity output averaged over the duration of ultrasound use in. The spatial-peak temporal-average power describes the measure of the highest intensity output generated by the repeating pulse of the ultrasound beam over a period of time.
Effects of Focused Ultrasound on Smart Hydrogels
Due to the sonication capability of ultrasound and drug-release property of smart hydrogels, there has been scientific interest in controlling the release of the payload from hydrogels. Focusing and directing acoustic energy (that can convert to thermal or mechanical energy) towards smart hydrogels, implanted within tissue at times, induces a hydrogel response that results in the release of the embedded payload. Although hydrogels that are sensitive to mechanical pressure are generally used in ultrasound-triggered drug delivery platforms, hydrogels that respond to changes in temperature have also been used for these systems. For example, Makhmalzadeh et al. proposed an ultrasound-triggered drug delivery method involving the use of thermo-responsive hydrogels loaded with silibinin, a cancer drug for treating melanoma. At low temperatures, these thermo-responsive hydrogels exist in liquid form but following ultrasonication, they transition into a gel state. Although ultrasound- and thermo-sensitive hydrogels are responsive to certain ultrasound modalities, they differ in how they respond to external stimuli. Ultrasound-responsive hydrogels are capable of being stimulated by more than one type of stimulation force through ultrasound. Conversely, thermo-responsive hydrogels, as the name specifies, can only respond to the thermal forces induced by ultrasound. Despite this, thermo-responsive hydrogels have been widely used in cancer-based drug delivery systems.
Of the existing ultrasound modalities, focused ultrasound has been used extensively in drug delivery research. High-Intensity Focused Ultrasound (HIFU) and Low-Intensity Focused Ultrasound are the two main techniques used in inducing drug release from smart hydrogels. Current HIFU applications are used for ablating tumors located at increased depths. Since HIFU is able to invoke high temperatures, they have been used for cancer therapy by stimulating drug release from smart hydrogels via thermolysis mechanisms. In regard to the use of ultrasound- and thermo-responsive hydrogels for drug delivery, HIFU is able to stimulate both types of hydrogels. In one study related to cancer therapy, HIFU exhibited high efficiency inducing nanovaccine release from hydrogel-based carriers. Although HIFU has been studied in various capacities, this technique can cause irreparable damage to healthy tissue. Therefore, LIFU has been the conventional method for use in hydrogel responsive drug delivery platforms. In other areas of the biomedical field, LIFU has been used for stimulation such as bone regeneration in tissue engineering applications. Due to its lower generated acoustic power output, LIFU is preferred over HIFU in biomedical applications involving neuromodulation and other brain-related procedures. Studies have shown that LIFU has proven to be a cost-effective and non-invasive method for hydrogel-based drug delivery.
The underlying drug-releasing mechanism induced by focused ultrasound onto ultrasound-sensitive hydrogels is based on mechanical or thermal effects. Mechanical-based ultrasound sonication mechanisms refer to the conversion of acoustic energy into mechanical energy with various types that include acoustic cavitation force, or oscillation force. Generally, applying mechanical pressure to a responsive hydrogel loaded with drugs causes the hydrogel to deform. This deformation reduces the structural integrity of the hydrophobic core, allowing for the release of the drug payload. Both ultrasound- and thermo- responsive hydrogels are capable of carrying various embedded carriers of drug payloads which include metal-organic framework, nanoparticles, and liposomes. Although many studies have demonstrated the irreversible compression of hydrogels induced under ultrasound, Goncalves et al. designed hydrogel-based nanoparticles that were capable of “self-healing”, meaning they were able to return to their original form following drug release from its depot.
Acoustic cavitation forces, specifically, have been used in conjunction with ultrasound-responsive hydrogels for drug delivery. This type of mechanical force refers to the formation, growth, and destruction of bubble occurs that results in the generation of acoustic energy. There are varying degrees of cavitation which divided into three groups: sonoporation, stable cavitation, and inertial cavitation. Sonoporation refers to the process of using ultrasound to open pores (or permeability) of cellular membranes to allow substances of interest to enter into the targeted cell. In cases where microbubbles are coated with hydrogels, these embedded carrier systems undergo stable cavitation and inertial cavitation. Stable cavitation characterizes vapor bubbles that oscillate within its own equilibrium, while inertial cavitation describes bubbles that generate a net growth each time the bubble expands and results in the bubble collapsing violently. Severe cavitation increases the risk of damage to tissue and drug degradation. Other forces generated by ultrasound that is used in several hydrogel-based platforms are hyperthermia and radiation. These forces are generally created by HIFU as they generate high levels of heat. Thus, guidelines established by the FDA help ensure the safe use of ultrasound in all biomedical applications, inclusive of drug delivery systems, based on the scientific understanding of these mechanical forces.
Drug delivery applications and effects
Tissue engineering
In regard to tissues, ultrasound is generally used for imaging and monitoring tissue pathologies. Due to its ability to penetrate through tissue easily, ultrasound has been widely studied and developed for drug delivery applications in the field of tissue engineering. In order for hydrogels to release drugs at the targeted location, they must be injected or implanted within the tissue. Injection of hydrogels is usually preferred over implantation due to its minimal invasiveness, reduced healing time following the procedure, and biocompatibility. In one study, Liu et al. proposed a novel design of injectable chemotaxis hydrogels to help promote the migration of bone marrow mesenchymal cells for cartilage repair. Other examples of using smart hydrogels and ultrasound in tissue engineering applications include cartilage repair, bone repair, and wound healing. The design of these drug delivery platforms is specific to each tissue type and its intended use.
Cancer treatment
In the field of cancer, ultrasound is commonly used for helping health care professionals detect and develop a diagnosis in affected patients. In the context of drug delivery, ultrasound has been used for a wide variety of therapeutic applications which include but are not limited to melanoma, ovarian cancer, and breast cancer. Hydrogels are generally used in designing these drug delivery platforms due to minimal invasiveness (if injected) and its ability to carry a different cancer drugs. These hydrogel-based systems are also paired with chemotherapy treatments. Cancer drugs used in this drug delivery platforms include doxorubicin, mitoxantrone, paclitaxel, silibinin, and cisplatin. In a cancer therapy study, Baghbani et al. proposed a method of pairing ultrasound with doxorubicin-loaded alginate-stabilized perfluorohexane (PFH) nanodroplets.
Gene therapy
Although it is generally used in combination with cancer therapeutic treatments, gene therapy has become a topic of interest in the drug delivery field. Gene therapy refers to the insertion of genes into a biological system in an attempt to add or modify mutated genes for therapeutic benefit. In order to attain high transgene expression, the electrostatic interaction between the gene and hydrogel polymer and the controlled release of the drug payload from the hydrogel is necessary. Several gene therapy drugs used in hydrogel-based drug delivery systems include CRISPR/Cas9, siRNA, and other RNA-based drugs. In a gene therapy study, Han et al. proposed a focused ultrasound-responsive hydrogel-based system for delivering siRNA nanoparticles to the targeted tumor site
Challenges and future development
The main challenge for future ultrasound-triggered hydrogel responsive delivery systems is to develop safer guidelines for using HIFU to take advantage of its benefits. In doing so, this will lead to improvements on FDA guidelines for ultrasound use. Therefore, the use of LIFU or lower acoustic energy intensity settings is suggested as the conventional method for decreasing injury risk, specifically damage to healthy tissue, until then. Focused ultrasound continues to be the primary type of ultrasound technique used in drug delivery systems. Another challenge presented in using ultrasound for inducing drug release from smart hydrogels in delivery platforms is inappropriate drug administration and unexpected complications. Currently, on-demand drug release from ultrasound-responsive hydrogels is still difficult to fully control when only using ultrasound. Yeingst et al. suggested that future hydrogel-based delivery platforms will be designed based on the drug payload to optimize the interaction between the ultrasound and stimuli-responsive hydrogel. Future development of drug delivery systems will continue to incorporate ultrasound and smart hydrogel designs.
References
Drug delivery devices
Ultrasound | Ultrasound-triggered drug delivery using stimuli-responsive hydrogels | [
"Chemistry"
] | 3,360 | [
"Pharmacology",
"Drug delivery devices"
] |
73,533,502 | https://en.wikipedia.org/wiki/In%20Another%20Room | In Another Room is an EP by English musician Paul Weller, released in January 2020 by electronic label Ghost Box. The label approached Weller to record a release for them, the musician having already taken influence from the label's music on previous releases. Recorded with longtime engineer Charles Rees, the project allowed Weller to create more outré music and explore his passions for tape music and electronics.
The EP contains four instrumentals and is a work of musique concrète, sound collage and experimental music, based on field recordings that Weller captured during his travels and everyday life. Tape manipulation was employed to give the project an analogue feel and change the speed of recordings. The record has also been considered a work of hauntology, a genre pioneered by Ghost Box.
In Another Room was a limited edition of 1,000 vinyl copies, although it was also available as a download. Critics contextualised the record as continuing Weller's more adventurous 2010s work. The musician later reused elements of the EP on his subsequent album On Sunset (2020).
Background and recording
Paul Weller had long been a fan of electronic label Ghost Box, and their influence on his music was apparent in eccentric recordings such as "Night Lights" from 22 Dreams (2008) and the lengthy sound collage "Jimmy/Blackout" from the Jawbone soundtrack (2017). The genesis of In Another Room came when Ghost Box founder Jim Jupp approached Weller to record material for the label; Jupp, who was surprised that Weller was a fan of Ghost Box, only infrequently followed his career until Saturns Pattern (2015) re-energised his interest; he said of the album: "I realised just how wide ranging his influences had become. It goes without saying what an incredible songwriter he is but, I love the way he weaves in his love of English folk and vintage electronics as well as the more obvious influences." Weller considered it "[a] great honour to be asked to do it as a fan of the label." Paul Osborne of Shindig! wrote that Ghost Box was the ideal label for Weller to explore "his love of experimental tape music and electronics", and provided him with the opportunity "to visit the more outrè corners of the musical spectrum."
Weller commented that once he knew Ghost Box were interested in a release, he began storing up ideas, later resulting in a wealth of sounds on the EP that were recorded from his iPhone. Early discussions between Weller and Jupp helped formalise some of the musician's ideas as well as "providing fresh inspiration", according to Jupp, who added that Weller sent him his Jawbone soundtrack album for "a flavour of what kind of instrumental work [the release] might be.". Jupp suggested the work result in a seven-inch single or EP, with no particular deadline attached, thus allowing Weller to "do something a bit more out there, which was certainly fine by us!"
The EP was created by Weller with long-time engineer Charles Rees, utilising field recordings "captured during [Weller's] travels and day to day life." The musician wrote, arranged, produced the EP and played most of its instrumentation, with Rees also credited for recording, mixing and production management. According to Rees, the principle of the recording "was whatever you were thinking, you could record and them manipulate it." To this end, tape manipulation was employed on the tracks to provide them with analogue atmosphere. Weller said: "We used the half-inch tape and put some sounds back onto that and fucked about with them and slowed them down or whatever." Besides Weller, other musicians on the album include Rees, who played Moog synthesiser on "Rejoice"; Tom Van Heel, who played Moog on the title track and "Submerge", as well as "prayer bowl" percussion on the latter and drums, vocals and glockenspiel on "Rejoice", and Jan Erika, whose cello work appears on "Submerge".
Composition
Containing four instrumental tracks, In Another Room has been referred to as a work of musique concrète, sound collage, experimental, and electronic music. Pat Gilbert of Mojo Essentials describes the contents as "four tracks of eerie field recordings and musique concrète". Kitty Empire wrote that while Weller had "dabbled in all sorts of outre soundmaking" since 22 Dreams (2008), with albums "as varied as they were regular", the musique concrète EP is arguably the "strangest of all". Osborne says that while the EP fits firmly into the musique concrète tradition, it features "subtle melodic undertones", and felt that the project's existence would not surprise those who had kept up with ten years of Weller's "sonic shape-shifting". In Another Room was partly influenced by Broadcast, whom Weller had long championed in interviews, and has drawn comparison to Delia Derbyshire, and Julian House's work with the Focus Group. Jupp compared the music to "a late Beatles studio experiment."
According to Mojo, the record is characterised by "spectral piano parts, white noise, doomy 'dongs', faraway voices and field recordings of birdsong and running water". Weller said of the EP: "Obviously a lot of it's random by the very nature of it but then there's an overall theme to it as well." The EP's sound collages and experiments exemplify the hauntology genre pioneered by Ghost Box, described as "atmospheric, often avant-garde electronic sounds that evoke buried shared cultural memories." Mojo consider the release to fit the label's "rubric of 'hauntology' impeccably." Clash consider In Another Room to showcase "sheer acid England, a kind of weird walk around the environs of [Weller's] native Woking", and noted the music's "fleeting glimpses, and a general sense of the uncanny [in its] grapples with a shadow England." They added that the release moves the songwriter's vision of the country from a bucolic to a radically dystopian one "with the twist of a dial", while adding a wry edge to his work by displaying "the rather more nostalgic side of the English hypnagogia espoused by some aspects of the folk horror guild."
According to Clash, the title track evokes "a fracture kind of pastoral landscape", with "wonky analogue electronics intruded upon by found-sounds." The bells on the track were recorded by Weller on a visit to Rishikesh. "Submerge" features deft effects, while "Embarkation" originated during the Jawbone soundtrack sessions; Weller said it "didn't work out so I managed to be able to re-do [the track]."
Release and reception
On 25 October 2019, Ghost Box announced In Another Room for a late January 2020 release, with previews and pre-orders would becoming available from December. Issued as a gatefold seven-inch record, the EP was limited to 1,000 copies and features artwork from Julian House. It was also released as a download on FLAC and MP3 formats.
In their review, Mojo wrote that while the idea of Weller "releasing an EP of eerie musique concrete" may have seemed highly unlikely a decade or so earlier, 2010s albums such as Sonik Kicks (2012) and Saturns Pattern (2015) had "acclimatised fans to the Modfather's increasingly experimental mindset," which reaches "an apogee" on In Another Room. They drew attention to the music's effective hauntology sound. Alexis Petridis of The Guardian similarly noted: "It's worth considering for a moment how unlikely the idea of Paul Weller releasing an EP of musique concrète experimentation on a leftfield electronic label would once have seemed. The results are appealingly eerie."
A reviewer for Clash wrote that throughout the 21st century, Weller had contrasted his 'Modfather' image with some of his most daring material, considering A Different Room to continue this dynamic. They deemed the EP "far from perfect", writing of "a sense of Weller shifting palettes – embracing a slightly uncomfortable mirror of a 1973 dreamscape he once rebelled against – but still working within rules". Despite this, they considered the record "supremely interesting" as an opportunity to hear the musician release "such, well, un-Weller music". They concluded: "An experiment with mixed results, In Another [Room] proves to have an illuminating impact that outshines much of the music underneath." In their review, Shindig! described the EP as a "visionary release".
Legacy
Weller later used some of the sound clips from In Another Room on his next album On Sunset (2020), most notably on its opening song "Mirror Ball". Pat Carty of Hot Press wrote that while the EP may have baffled Weller's fans, it acted as a "signpost" of his change of direction, noting that the musique concrète breakdown in "Mirror Ball" continues the musician's experimentation. Similarly, Peter Watts of Uncut noted that Weller's experience making the hauntological EP "found its way into On Sunset", while NME writer Mark Beaumont wrote that with On Sunset, Weller merges the "avant-garde montage methods" of musique concrète from In Another Room with "a rich seam of classic '70s funk, lounge and sci-fi soul. The album also continued Weller's collaboration with Jupp, as the pair wrote the futuristic R&B song "Earth Beat" together.
Track listing
All songs written by Paul Weller.
Side one
"In Another Room" – 1:43
"Submerge" – 2:18
Side two
"Embarkation" – 1:55
"Rejoice" – 1:36
Personnel
Adapted from the liner notes of In Another Room
Paul Weller – instrumentation, arrangements, production, writer
Charles Rees – recording, mixing, production manager, Moog synthesiser ("Rejoice")
Julian House – cover design
Tom Van Heel – Moog synthesiser ("In Another Room" and "Submerge"), prayer bowl ("Submerge"), glockenspiel ("Rejoice"), vocals ("Rejoice"), drums ("Rejoice")
Jan Erika – cello ("Rejoice")
References
2020 EPs
Paul Weller EPs
Ghost Box Music EPs
Musique concrète albums
Sound collage albums
Electronic EPs
Electronic albums by English artists
Field recording
Experimental music EPs
Experimental music albums by English artists
Instrumental EPs
Electroacoustic music albums
Hauntology | In Another Room | [
"Engineering"
] | 2,227 | [
"Audio engineering",
"Field recording"
] |
73,535,300 | https://en.wikipedia.org/wiki/Infertility%20and%20childlessness%20stigmas | Infertility and childlessness stigmas are social and cultural codes that identify the inability to have children as a disgraceful state of being. Broadly speaking, in many cultures, "Demonstrating fertility is necessary to be considered a full adult, a real man or woman, and to leave a legacy after death," and thus the failure to make this demonstration is penalized. Both male infertility and female infertility can be stigmatized, however, in many traditional cultures, women are held responsible for child-rearing and thus for pregnancy or the lack thereof. Infertility and childlessness stigmas are related to disability or physical-deformity stigmas and violation-of-group-norm stigmas. Infertility is a "deeply intimate matter, often deemed as taboo to discuss publicly."
Infertility and childlessness can have negative social, psychological and economic consequences, including "discrimination, social exclusion, and abandonment." Adults without children may be subject to derisive language, intrusive questioning, shaming, ostracism, and physical abuse. Other negative consequences of the infertility–childlessness stigma, especially for women, may include depression, low self-esteem, and even suicidal ideation or suicide. People with infertility living in societies where it is a stigmatized condition may suffer from anxiety, may choose to self-isolate, and may become secretive or withdrawn. In pro-natalist societies, voluntary childlessness is often considered a deviant behavior.
Stigmas may be particularly acute in communities that organize themselves collectively and thus place a high value on clan, lineage and perpetuation of family legacy. In these cultures, childlessness may be viewed as a "tragedy for the whole community" beyond the personal significance for infertile or childless individuals. However, even in a prototypically individualistically organized society, 42 percent of women tested in a study of the emotional consequences of infertility were found to have "global distress levels in the clinically significant range," in part due to social norms that judge women without children to be "unnatural and selfish."
Most academic study of infertility addresses expensive treatment technologies, rather than the "anthropological and public health" effects. In more-developed countries, the widespread availability of assisted reproductive technologies has "transformed infertility from an acute, private agony that was accepted as fate, into a chronic, public stigma from which there were costly, and often unfulfilled hopes, of deliverance." In some cultures, biomedical explanations for infertility may be disregarded in favor of traditional beliefs that past wrong choices have resulted in the placement of an infertility curse, thus accelerating the vicious cycle of stigma. Blame may assigned, variously, to having offended gods or ancestors, abortions in a past life, practicing witchcraft, past promiscuity, use of birth control, wrong living generally, etc. Exclusion of the infertile or childlessness from social events is known, enacted as a means of quarantine to prevent the "contagion" or "toxin" of non-reproduction from spreading within the community. Infertile people are also viewed as sad people who may bring sadness with them and "spoil" celebrations.
As one scholar put it, "Like leprosy and epilepsy, infertility bears an ancient social stigma. An archaic term for the condition of female infertility, present in the Old Testament, is barren woman. There have been three traditional means of addressing infertility:
Medical interventions or quasi-medical treatments; the ancient Greeks called childless women ateknos, and possible causes and treatments for infertility were considered in Hippocratic texts.
Spiritual recourse (prayer for fecundity, or alternately, submission to the will of a deity or power)
Realignment of social relationships, including divorce, polygamy, adultery, or promiscuity. One study showed that infertility in Ghana led to "increased risk of precarious sexual behaviour of both men and women...trying out different partners, attempting to prove that they are not the source of the infecundity." In traditional Chinese family structure (called the Dishu system in English), "The first of the seven conditions under which a wife may be repudiated is infecundity."
In some societies, women with children are allowed access to certain community resources and privileges from which childless women may be excluded, thus children act as a sort of universal passport to humanity.
In some cultures, funeral practices for childless women are different from those for women who successfully conceived and bore offspring. Notably, "In the Hindu religion, a woman without a child, particularly a son, can't go to heaven. Sons perform death rituals." In Catholicism, there is a limbo of infants for stillborn babies (as baptism is a sacrament available only to the living), thus women unable to bring a pregnancy to term would be told they would not encounter their children's souls in an afterlife. The original doctrine was that these fetuses or babies were consigned to hell, resulting in a latter-day practice called respite sanctuaries. In the traditional Vietnamese belief system, childlessness risks destroying "the entire âm realm of one's ancestors and consequently scatters all ancestral linh hon into wandering ghosts and demons (ma qüy)."
An individual's ability to deflect or resist stigma may depend on array of intersecting age, gender, class, economic, and/or psychological factors.
A study of infertility experiences in Zambia concluded:
See also
Reproductive privilege
Reproductive loss
Son preference
Third-party reproduction
Stratified reproduction
Shunning
Ableism
Status symbol
Cultural variations in adoption
Human reproductive ecology
Fertility and religion
Fertility rite
Fertility in art
References
External links
Books To Read If You're Struggling With Infertility Or Pregnancy Loss Kristyn Hodgdon Mar 9, 2021
9 Books That Helped Me Through My Infertility Alexandra Kimball May 10, 2019
Infertility
Social stigma
Cultural anthropology
Kinship and descent
Human reproduction | Infertility and childlessness stigmas | [
"Biology"
] | 1,246 | [
"Behavior",
"Human behavior",
"Kinship and descent"
] |
73,535,353 | https://en.wikipedia.org/wiki/Lys-MDA | Lys-MDA (Lysine-MDA, N-(L-lysinamidyl)-3,4-methylenedioxyamphetamine) is a substituted amphetamine derivative with empathogenic effects, which acts as a prodrug for MDA with a slower onset of effects and longer duration of action. Lys-MDA, along with the related derivative Lys-MDMA, are in early stage human clinical trials as potential treatments for treatment-resistant depression and post-traumatic stress disorder. New MDMA prodrugs are in the development phase at MiHKAL GmbH in Switzerland. A phase 1 clinical trial comparing MDMA, MDA, Lys-MDMA, and Lys-MDA has been completed as of August 2024.
See also
Lisdexamfetamine
Serdexmethylphenidate
N-t-BOC-MDMA
References
Designer drugs
Entactogens and empathogens
Prodrugs
Serotonin-norepinephrine-dopamine releasing agents
Substituted amphetamines | Lys-MDA | [
"Chemistry"
] | 230 | [
"Chemicals in medicine",
"Prodrugs"
] |
73,535,423 | https://en.wikipedia.org/wiki/Boletus%20leptospermi | Boletus leptospermi is a fungal species in the family Boletaceae.
Description
Boletus leptospermi has a cap that ranges in color from yellow-brown to reddish-brown and can grow up to 4–8 cm in diameter. The cap surface is velvety to the touch and can sometimes become cracked in dry weather. The stem is yellow and can grow up to 3–5 cm in length. The cap and stem turn blue when damaged or cut. The pores on the underside of the cap are initially dull yellow, becoming golden-yellow with age.
Range and habitat
It is endemic to Aotearoa New Zealand.
and commonly found in native forests throughout the North and South Islands.
Ecology
Boletus leptospermi forms a symbiotic relationship with the roots of kānuka and mānuka and beech trees. The fungus likely helps the trees and shrubs to absorb nutrients from the soil in exchange for sugars produced by the tree through photosynthesis.
Etymology
The specific epithet "leptospermi" is derived from the genus Leptospermum as the fungus was first described in association with Leptospermum scrub.
Taxonomy
Based on molecular DNA markers, Nuhn et al. (2013) suggest that the species described by McNabb in 1968 is rather a species in the genus Xerocomus.
References
leptospermi
Fungi of New Zealand
Fungus species | Boletus leptospermi | [
"Biology"
] | 294 | [
"Fungi",
"Fungus species"
] |
73,535,503 | https://en.wikipedia.org/wiki/List%20of%20female%20Clarivate%20Citation%20laureates | The following is a list of candidates considered likely to win the Nobel Prize in their respective field. The candidates are so named based on the citation impact of their published research. Since 2024, six of the 29 female Clarivate Citation laureates starting in 2008 were subsequently awarded with a Nobel Prize: Elizabeth Blackburn and Carol W. Greider in Physiology or Medicine (2009), Emmanuelle Charpentier and Jennifer Doudna in Chemistry (2020), Carolyn Bertozzi in Chemistry (2022), and Claudia Goldin in Economics (2023).
Female Citation laureates
References
External links
Clarivate
Nobel laureates
Women Nobel laureates
Lists of women scientists | List of female Clarivate Citation laureates | [
"Technology"
] | 138 | [
"Women Nobel laureates",
"Women in science and technology"
] |
73,536,266 | https://en.wikipedia.org/wiki/Fixed-point%20computation | Fixed-point computation refers to the process of computing an exact or approximate fixed point of a given function. In its most common form, the given function satisfies the condition to the Brouwer fixed-point theorem: that is, is continuous and maps the unit d-cube to itself. The Brouwer fixed-point theorem guarantees that has a fixed point, but the proof is not constructive. Various algorithms have been devised for computing an approximate fixed point. Such algorithms are used in economics for computing a market equilibrium, in game theory for computing a Nash equilibrium, and in dynamic system analysis.
Definitions
The unit interval is denoted by , and the unit d-dimensional cube is denoted by . A continuous function is defined on (from to itself). Often, it is assumed that is not only continuous but also Lipschitz continuous, that is, for some constant , for all in .
A fixed point of is a point in such that . By the Brouwer fixed-point theorem, any continuous function from to itself has a fixed point. But for general functions, it is impossible to compute a fixed point precisely, since it can be an arbitrary real number. Fixed-point computation algorithms look for approximate fixed points. There are several criteria for an approximate fixed point. Several common criteria are:
The residual criterion: given an approximation parameter , An -residual fixed-point of is a point in ' such that , where here denotes the maximum norm. That is, all coordinates of the difference should be at most .
The absolute criterion: given an approximation parameter , A δ-absolute fixed-point of is a point in such that , where is any fixed-point of .
The relative criterion: given an approximation parameter , A δ-relative fixed-point of is a point x in such that , where is any fixed-point of .
For Lipschitz-continuous functions, the absolute criterion is stronger than the residual criterion: If is Lipschitz-continuous with constant , then implies . Since is a fixed-point of , this implies , so . Therefore, a δ-absolute fixed-point is also an -residual fixed-point with .
The most basic step of a fixed-point computation algorithm is a value query: given any in , the algorithm is provided with an oracle to that returns the value . The accuracy of the approximate fixed-point depends upon the error in the oracle .
The function is accessible via evaluation queries: for any , the algorithm can evaluate . The run-time complexity of an algorithm is usually given by the number of required evaluations.
Contractive functions
A Lipschitz-continuous function with constant is called contractive if ; it is called weakly-contractive if . Every contractive function satisfying Brouwer's conditions has a unique fixed point. Moreover, fixed-point computation for contractive functions is easier than for general functions.
The first algorithm for fixed-point computation was the fixed-point iteration algorithm of Banach. Banach's fixed-point theorem implies that, when fixed-point iteration is applied to a contraction mapping, the error after iterations is in . Therefore, the number of evaluations required for a -relative fixed-point is approximately . Sikorski and Wozniakowski showed that Banach's algorithm is optimal when the dimension is large. Specifically, when , the number of required evaluations of any algorithm for -relative fixed-point is larger than 50% the number of evaluations required by the iteration algorithm. Note that when approaches 1, the number of evaluations approaches infinity. No finite algorithm can compute a -absolute fixed point for all functions with .
When < 1 and d = 1, the optimal algorithm is the Fixed Point Envelope (FPE) algorithm of Sikorski and Wozniakowski. It finds a δ-relative fixed point using queries, and a δ-absolute fixed point using queries. This is faster than the fixed-point iteration algorithm.
When but not too large, and , the optimal algorithm is the interior-ellipsoid algorithm (based on the ellipsoid method). It finds an -residual fixed-point using evaluations. When , it finds a -absolute fixed point using evaluations.
Shellman and Sikorski presented an algorithm called BEFix (Bisection Envelope Fixed-point) for computing an -residual fixed-point of a two-dimensional function with ', using only queries. They later presented an improvement called BEDFix (Bisection Envelope Deep-cut Fixed-point), with the same worst-case guarantee but better empirical performance. When , BEDFix can also compute a -absolute fixed-point using queries.
Shellman and Sikorski presented an algorithm called PFix for computing an -residual fixed-point of a d-dimensional function with L ≤ 1, using queries. When < 1, PFix can be executed with , and in that case, it computes a δ-absolute fixed-point, using queries. It is more efficient than the iteration algorithm when is close to 1. The algorithm is recursive: it handles a d-dimensional function by recursive calls on (d-1)-dimensional functions.
Algorithms for differentiable functions
When the function is differentiable, and the algorithm can evaluate its derivative (not only itself), the Newton method can be used and it is much faster.
General functions
For functions with Lipschitz constant > 1, computing a fixed-point is much harder.
One dimension
For a 1-dimensional function (d = 1), a -absolute fixed-point can be found using queries using the bisection method: start with the interval ; at each iteration, let be the center of the current interval, and compute ; if then recurse on the sub-interval to the right of ; otherwise, recurse on the interval to the left of . Note that the current interval always contains a fixed point, so after queries, any point in the remaining interval is a -absolute fixed-point of Setting , where is the Lipschitz constant, gives an -residual fixed-point, using queries.
Two or more dimensions
For functions in two or more dimensions, the problem is much more challenging. Shellman and Sikorski proved that for any integers d ≥ 2 and > 1, finding a δ-absolute fixed-point of d-dimensional -Lipschitz functions might require infinitely many evaluations. The proof idea is as follows. For any integer T > 1 and any sequence of T of evaluation queries (possibly adaptive), one can construct two functions that are Lipschitz-continuous with constant , and yield the same answer to all these queries, but one of them has a unique fixed-point at (x, 0) and the other has a unique fixed-point at (x, 1). Any algorithm using T evaluations cannot differentiate between these functions, so cannot find a δ-absolute fixed-point. This is true for any finite integer T.
Several algorithms based on function evaluations have been developed for finding an -residual fixed-point
The first algorithm to approximate a fixed point of a general function was developed by Herbert Scarf in 1967. Scarf's algorithm finds an -residual fixed-point by finding a fully labeled "primitive set", in a construction similar to Sperner's lemma.
A later algorithm by Harold Kuhn used simplices and simplicial partitions instead of primitive sets.
Developing the simplicial approach further, Orin Harrison Merrill presented the restart algorithm.
B. Curtis Eaves presented the homotopy algorithm. The algorithm works by starting with an affine function that approximates , and deforming it towards while following the fixed point. A book by Michael Todd surveys various algorithms developed until 1976.
David Gale showed that computing a fixed point of an n-dimensional function (on the unit d-dimensional cube) is equivalent to deciding who is the winner in a d-dimensional game of Hex (a game with d players, each of whom needs to connect two opposite faces of a d-cube). Given the desired accuracy
Construct a Hex board of size kd, where . Each vertex z corresponds to a point z/k in the unit n-cube.
Compute the difference (z/k) - z/k; note that the difference is an n-vector.
Label the vertex z by a label in 1, ..., d, denoting the largest coordinate in the difference vector.
The resulting labeling corresponds to a possible play of the d-dimensional Hex game among d players. This game must have a winner, and Gale presents an algorithm for constructing the winning path.
In the winning path, there must be a point in which fi(z/k) - z/k is positive, and an adjacent point in which fi(z/k) - z/k is negative. This means that there is a fixed point of between these two points.
In the worst case, the number of function evaluations required by all these algorithms is exponential in the binary representation of the accuracy, that is, in .
Query complexity
Hirsch, Papadimitriou and Vavasis proved that any algorithm based on function evaluations, that finds an -residual fixed-point of f, requires function evaluations, where is the Lipschitz constant of the function (note that ). More precisely:
For a 2-dimensional function (d=2), they prove a tight bound .
For any d ≥ 3, finding an -residual fixed-point of a d-dimensional function requires queries and queries.
The latter result leaves a gap in the exponent. Chen and Deng closed the gap. They proved that, for any d ≥ 2 and and , the number of queries required for computing an -residual fixed-point is in .
Discrete fixed-point computation
A discrete function is a function defined on a subset of (the d-dimensional integer grid). There are several discrete fixed-point theorems, stating conditions under which a discrete function has a fixed point. For example, the Iimura-Murota-Tamura theorem states that (in particular) if is a function from a rectangle subset of to itself, and is hypercubic direction-preserving, then has a fixed point.
Let be a direction-preserving function from the integer cube to itself. Chen and Deng prove that, for any d ≥ 2 and n > 48d, computing such a fixed point requires function evaluations.
Chen and Deng define a different discrete-fixed-point problem, which they call 2D-BROUWER. It considers a discrete function on such that, for every x on the grid, (x) - x is either (0, 1) or (1, 0) or (-1, -1). The goal is to find a square in the grid, in which all three labels occur. The function must map the square to itself, so it must map the lines x = 0 and y = 0 to either (0, 1) or (1, 0); the line x = n to either (-1, -1) or (0, 1); and the line y = n to either (-1, -1) or (1,0). The problem can be reduced to 2D-SPERNER (computing a fully-labeled triangle in a triangulation satisfying the conditions to Sperner's lemma), and therefore it is PPAD-complete. This implies that computing an approximate fixed-point is PPAD-complete even for very simple functions.
Relation between fixed-point computation and root-finding algorithms
Given a function from to R, a root of is a point x in such that (x)=0. An -root of g is a point x in such that .
Fixed-point computation is a special case of root-finding: given a function on , define . X is a fixed-point of if and only if x is a root of , and x is an -residual fixed-point of if and only if x is an -root of . Therefore, any root-finding algorithm (an algorithm that computes an approximate root of a function) can be used to find an approximate fixed-point.
The opposite is not true: finding an approximate root of a general function may be harder than finding an approximate fixed point. In particular, Sikorski proved that finding an -root requires function evaluations. This gives an exponential lower bound even for a one-dimensional function (in contrast, an -residual fixed-point of a one-dimensional function can be found using queries using the bisection method). Here is a proof sketch. Construct a function that is slightly larger than everywhere in except in some small cube around some point x0, where x0 is the unique root of . If is Lipschitz continuous with constant , then the cube around x0 can have a side-length of . Any algorithm that finds an -root of must check a set of cubes that covers the entire ; the number of such cubes is at least .
However, there are classes of functions for which finding an approximate root is equivalent to finding an approximate fixed point. One example is the class of functions such that maps to itself (that is: is in for all x in ). This is because, for every such function, the function satisfies the conditions of Brouwer's fixed-point theorem. X is a fixed-point of if and only if x is a root of , and x is an -residual fixed-point of if and only if x is an -root of . Chen and Deng show that the discrete variants of these problems are computationally equivalent: both problems require function evaluations.
Communication complexity
Roughgarden and Weinstein studied the communication complexity of computing an approximate fixed-point. In their model, there are two agents: one of them knows a function and the other knows a function . Both functions are Lipschitz continuous and satisfy Brouwer's conditions. The goal is to compute an approximate fixed point of the composite function . They show that the deterministic communication complexity is in .
References
Further reading
Fixed-point theorems
Numerical analysis | Fixed-point computation | [
"Mathematics"
] | 2,912 | [
"Theorems in mathematical analysis",
"Computational mathematics",
"Fixed-point theorems",
"Theorems in topology",
"Mathematical relations",
"Numerical analysis",
"Approximations"
] |
73,536,579 | https://en.wikipedia.org/wiki/Book%20on%20the%20Measurement%20of%20Plane%20and%20Spherical%20Figures | The Book on the Measurement of Plane and Spherical Figures (, ) was the most important of the works produced by the Banū Mūsā (three 9th century Persian brothers who worked in Baghdad). A Latin translation by the 12th century Italian astrologer Gerard of Cremona was made, entitled and . The original work in Arabic was edited by the Persian polymath Naṣīr al-Dīn al-Ṭūsī in the 13th century. The original work in Arabic is not extant, but its contents are known from later translations.
The treatise, which is about geometry, was similar to two books by Archimedes, On the measurement of the circle and On the sphere and the cylinder. It was used extensively in the Middle Ages, and was quoted by authors such as Thābit ibn Qurra, Ibn al-Haytham, Leonardo Fibonacci (in his ), Jordanus de Nemore, and Roger Bacon. It deals with the geometrical concepts of area and volume, angle trisection, construction, and conic sections. It includes theorems not known to the Greeks.
The book was re-published in Latin with an English translation by the American historian Marshall Clagett, who has also summarized how the work influenced mathematicians during the Middle Ages.
See also
Mathematics in the medieval Islamic world
Notes
References
Sources
(PDF version)
Further reading
A manuscript facsimile of kept at Columbia University, New York (via the Internet Archive). The treatise is located from pp. 253265 (f. 116 to 122).
Mathematical works of the medieval Islamic world
History of geometry
Scientific works of the Abbasid Caliphate
9th-century Arabic-language books | Book on the Measurement of Plane and Spherical Figures | [
"Mathematics"
] | 335 | [
"History of geometry",
"Geometry"
] |
73,537,002 | https://en.wikipedia.org/wiki/Tare%20%28legume%29 | Wild tare or tare is the name given to several flowering plants of the pea family (Fabaceae), of the genus Vicia, or 'vetch', hence they look very similar to the vetches in the same genus. These plants are found in Britain and northern Europe and have flowers ranging from pale to deep lilac in colour. Three species found in Britain are hairy tare (Vicia hirsuta), smooth tare (Vicia tetrasperma), and slender tare (Vicia tenuissima).
References
Vicia
Plant common names | Tare (legume) | [
"Biology"
] | 122 | [
"Plants",
"Plant common names",
"Common names of organisms"
] |
73,537,806 | https://en.wikipedia.org/wiki/Cafileria | Cafileria is a genus of marine microscopic protists. It is monotypic, comprising the single species Cafileria marina, described in 2019 from Norway. It is part of a clade of heterotrophic flagellates that consume bacteria, known as Bicosoecida, a basal lineage of Stramenopiles. Due to its small size it is described as a nanoflagellate. It is the only organism where direct connections between mitochondria and the cell nucleus have been observed. Another peculiarity of C. marina is the change in shape of the Golgi apparatus during the cell cycle.
Discovery
Cells of Cafileria marina were sampled from part of an algal mat community in a rock surface from Kvernesfjord, Norway. Their morphology, ultrastructure, flagellar apparatus and mitochondrial genome were investigated. The results, along with the formal taxonomic description of Cafileria marina, were published in 2019 by Czech researchers Dagmar Jirsová, Zoltán Füssy, Jitka Richtová, Ansgar Gruber and Miroslav Oborník.
The hapantotype of C. marina was deposited under the name IP CAS Pro 59 in the slide collection at the Biological Centre of the Czech Academy of Sciences in České Budějovice, Czech Republic.
Etymology
Cafileria is named after , the Czech name for a rendering plant where the biomass of animal origin is transformed for the production of lipids, glue and fertilizers. In a parallel manner, Cafileria feasts on bacteria and recycles organic materials that are part of their biofilm habitat. The species epithet marina is due to the marine origin of the species.
Cell structure
External appearance
Cells of C. marina are rounded on the right side and flattened on the left side, resembling the shape of a "D". The cell body is 3–4 μm wide and 5–6 μm long, making it a nanoflagellate by size. The cellular surface is smooth, without any features (no lorica, cell wall, etc.) visible by light or scanning electron microscopy. Like other bicosoecids, they have two smooth flagella (anterior and posterior), with an equal length of around 1.5–2 times the length of the cell body. The flagella are in a sub-apical position and emerge from a dent on the ventral side.
Organelles
C. marina cells localize their nucleus and mitochondria with tubular cristae (as is common in Stramenopiles) in the anterior part of the cell. A peculiar phenomenon in C. marina is that, in young cultures (≤ 2 weeks old), the nucleus and mitochondria are tightly connected through junctions. Although clustering of mitochondria near the nucleus is seen in mammalian tissues, this is the first time that a full connection between these compartments has been described. Various functions for this peculiar connection have been hypothesized:
(i) enabling the exchange of ATP/ADP between the two organelles, thereby providing the high energy needed by the nucleus,
(ii) facilitating the transport of necessary nuclear tRNA that the mitochondria cannot produce,
(iii) transporting mRNA to be translated in the mitochondria,
(iv) equally segregating mitochondria to the daughter cells after mitosis,
(v) or simply a more efficient use of the limited space in a small cell size.
The Golgi apparatus is in the anterior part of the cell, with its 4–5 cisternae aligned parallel to the nuclear envelope. During the cell cycle, the shape of the Golgi cisternae changes from flat-stacked to rounded: the flat cisternae curve inside and create hollowed rounded shapes. A similar phenomenon happens in mammalian cells, in association with changes in sphingomyelin metabolism, but in the case of Cafileria the mechanism responsible is unknown.
Several small vesicles are scattered across the cytosol, while food vacuoles are considerably larger and are localized in the posterior part of the cell, occupying almost one third of its volume. Some of the food vacuoles can contain intact or partially digested bacteria.
Flagellar apparatus
C. marina has its two flagella attached to four roots made of microtubules. There are two basal bodies, in the anterior (front) part of the cell, at a 45° angle to each other, connected to each other through a striated fiber. The flagella each have an axoneme structure with two central microtubules and a circle of nine microtubules around them. The four roots (named R1, R2, R3 and R4) have 8, 3, 1, and 1 microtubules respectively, an arrangement unique to C. marina.
Ecology and cell behavior
Cafileria marina lives in close association with an unidentified species of pelagophyte alga. It glides through the mucilage secreted by the pelagophyte. While moving, it exhibits a tumbling motion, with the anterior flagellum freely sweeping while the posterior one is used as an anchor, attached to the surface. It is constantly feeding through phagotrophy, with a permanent cytostome; no resting stages or spores have been observed.
Genetic characteristics
The mitochondrial genome of C. marina is 42,797 base pairs long, with a content of 21.3% CG (cytosine-guanine pairs), much lower than other heterotrophic stramenopile mitochondrial genomes.
The genetic code of the mitochondrial genome is an unusual type 4 code, found across different prokaryotic and eukaryotic groups, in which the UGA codon codes for the aminoacid tryptophan and the UAA/UAG codons are the stop codons. The mitochondrial genome is also unusual in lacking any group I or group II introns, which are typical of other mitochondria.
The mitochondrial genome contains genes for all tRNAs except for threonine, alanine and glycine—which are carried by nuclear tRNAs instead—, large and small subunit ribosomal RNA genes arranged in tandem, and protein-coding genes for subunits of several complexes: respiratory complexes (I, III and IV), ATP synthase, and the protein portion of the large and small subunits of ribosomes. Despite having a very similar gene content compared to other heterotrophic stramenopiles, the order of genes is highly rearranged in C. marina. For example, it is the only stramenopile species known to encode the nad11 gene (a subunit of NADH-ubiquinone oxidoreductase) with 4Fe–4S domains within the N-terminal ferredoxin-type module, instead of the C-terminal molybdopterin-type module, although the consequences of this change are unclear.
Evolutionary relationships
Cafileria belongs to the Bicosoecida lineage, a basal stramenopile clade, but its position within this group is still unclear. According to the study that described Cafileria marina in 2019, phylogenetic and morphological analyses group the family Cafeteriidae as the closest relative of Cafileria marina, with Caecitellus as the sister taxon of C. marina, though the authors explain "further investigation is [...] needed to confirm this claim". A posterior analysis from 2022 recovered Cafileria outside the Anoecales; as the authors put it, "The phylogenetic resolution of the bicosoecids is still an ongoing issue".
References
External links
at UniEuk Taxonomy
Bikosea
Taxa described in 2019
Heterokont genera
Biota of Norway | Cafileria | [
"Biology"
] | 1,611 | [
"Biota by country",
"Biota of Norway"
] |
73,537,840 | https://en.wikipedia.org/wiki/Intranasal%20drug%20delivery | Intranasal drug delivery occurs when particles are inhaled into the nasal cavity and transported directly into the nervous system. Though pharmaceuticals can be injected into the nose, some concerns include injuries, infection, and safe disposal. Studies demonstrate improved patient compliance with inhalation. Treating brain diseases has been a challenge due to the blood brain barrier. Previous studies evaluated the efficacy of delivery therapeutics through intranasal route for brain diseases and mental health conditions. Intranasal administration is a potential route associated with high drug transfer from nose to brain and drug bioavailability.
History of drug delivery
Drug delivery is a process of administering therapeutics to treat human diseases. The first drug delivery system is often dated to the 1950s, when Smith Kline & French Laboratories introduced the Spansule technology. Between 1950s and 1980s, there were four drug release systems developed for oral and transdermal applications: dissolution, diffusion, osmosis, and ion-exchange controlled release. Later in the 1980s, the Lupron Depot technology further advanced the field by offering zero-order and long-term release systems. The intranasal route gained interest towards the end of the 20th century with treating cardiovascular and respiratory diseases. During the late 1980s, William Frey II studied the intranasal route for treating brain diseases. Ever since, it has become a potential route for nose-to-brain delivery.
Anatomy
Intranasal delivery pathway
The nasal cavity is highly vascularized, allowing efficient transfer of molecules directly to the nervous system. Compared to other administration routes, nasal drug delivery increases bioavailability and reduces systemic exposure risks. The nasal cavity’s slightly acidic environment and enzymes can affect drug degradation, making delivery systems with neutral to acidic pH ideal. The respiratory region, with its large surface area and high vascularization, is the primary site for drug absorption into systemic circulation. Targeting the olfactory region enhances nose-to-brain drug delivery, as particles can travel via the olfactory nerve to the brain. This route offers potential for treating brain diseases and mental health conditions.
Blood brain barrier
The blood-brain barrier (BBB) is a semipermeable membrane that separates the blood from the brain’s interstitial fluid. It is formed by tight junctions between endothelial cells, astrocytes, and pericytes in the brain’s capillaries, and has high electrical resistance. The BBB is crucial for protecting the brain from pathogens and toxic substances, maintaining homeostasis, and preventing alterations to neuronal functions. However, some diseases can damage the BBB, causing leakage. Research suggests that increasing intake of vitamins and antioxidants, as well as reducing stress, can help restore the BBB. Due to its selective nature, the BBB restricts the passive diffusion of solutes, large and hydrophilic molecules, and immune factors, making it challenging to deliver pharmaceuticals directly to the brain.
Recent studies on nose-to-brain drug delivery
Alzheimer's
Neurodegenerative diseases occur from loss of neuronal structure and function. This progressive degeneration of neurons is irreversible. Alzheimer's is a neurodegenerative disease that begins with short-term memory loss progressing to loss of control over heartbeat and breathing. It has been over 100 years since Alois Alzheimer first presented the world disease to the world in 1906. There is evidence for the efficacy of intranasal delivery to treat Alzheimer's. Intranasal delivery of insulin showed greater memory improvement in patients with Alzheimer's than in healthy individuals. Increased microglial activation inflammation are characteristics of Alzheimer's. Animal studies show intranasal administration of pro-resolving lipid mediators decreased both factors, slowing pathogenesis of this disease. Delivering a novel peptide via intranasal route reduced amyloid beta plaques, a defining trait of Alzheimer's and enhanced cognitive functions. Intranasal delivery of anti-Alzheimer's drug dispersed through hydrogel in rabbits demonstrated higher bioavailability compared to oral tablets. MiR132 is an RNA molecule that regulates neuronal morphology and maintains survival. This molecule is downregulated with Alzheimer's. A study administered PEG-PLA nanoparticles loaded with this miRNA to mice through the nasal route. This novel therapy showed increased expression of miR132 and improved memory function. To strengthen the effectiveness of intranasal delivery, there are studies to develop permeation enhancers to better improve drug transport across the blood brain barrier.
Glioblastoma
Abnormal cell growth and formation of mass in the brain tissue or nearby regions may cause brain cancer. Constant headaches, seizures, and blurred vision are common symptoms. Glioblastoma (GBM) is the most fast-growing and deadliest brain tumor. Though the main cause of glioblastoma remains unknown, it originates when astrocytes mutate and multiply uncontrollably forming tumors in the frontal and temporal lobes of the brain. The challenge with current therapeutics is to initiate tumor cell apoptosis with no toxic effects to healthy brain tissue. Nanoparticles loaded with chemotherapeutics delivered through the intranasal route show promising results in treating glioblastoma. PLGA-based nanoparticles loaded with paclitaxel or doxorubicin conjugated with a RGD sequence targeted the glioblastoma microenvironment and reduced tumor volume through cell death. MicroRNA-21 (miR-21) inhibits pro-apoptotic genes increasing progression of glioblastoma. Self-assembling nanoparticles produced with anti-tumor peptides were administered intranasally and reduced miR-21 levels increasing tumor cell apoptosis.
Epilepsy
Infection, head injury, or strokes can cause sudden bursts of neuronal activity leading to abnormal behaviors, muscle movement, and mood changes. This condition is known as seizure. Epilepsy is characterized by recurring seizures. Some possible causes of epilepsy include imbalance or disruption of neurotransmitters, strokes, or brain injury. Intranasal delivery of carbamazepine nanoparticles increase antiepileptic drug bioavailability. Administering a self-assembling hydrogel with neuroactive drugs to treat Parkinson's disease appears to be biocompatible, low in toxicity, and have a good recovery capacity. Nasal delivery of this gel demonstrated increased drug concentration in the brain. Oxytocin is a hormone which is observed to alleviate anxiety symptoms in people with autism. Intranasal administration indicated efficient transfer of pharmacologically active oxytocin from nasal cavity to brain.
Parkinson's
Similar to Alzheimer's, Parkinson's is the most common neurodegenerative disease associated with balance and coordination issues, muscle stiffness, and tremors. During the early 1800s, James Parkinson medically defined this disease. A study observed improvement in locomotor abilities in rats with Parkinson's after intranasal delivery of conjugated mitochondrial systems. Another study demonstrated delivery of neuroactive drugs in a hydrogel increased residence times in the nasal cavity and concentration in the brain. Administering therapeutics combined with nanocarriers is shown to directly transfer drugs to the target cells and enhance accumulation. The observed effects include improved neuronal signaling and locomotion. Furthermore, intranasal delivery of biodegradable nanoparticles surface-modified with lactoferrin increase accumulation in the brain and cellular uptake.
Depression
Characterized by loss of neuroplasticity, depression is a common mood disorder causing persistent negative emotions and changes in lifestyle. Intranasal delivery of relaxin-3 mimetics demonstrated significant anti-depressant activity in behavior paradigms of rat models. Delivering a thermoresponsive hydrogel loaded with berberine intranasally exhibited high bioavailability in hippocampus and anti-depressant activity.
Anxiety
Anxiety can impair hippocampus function which increases risk of depression and dementia. Anxiolytic effects were observed in animal models post-intranasal delivery of a loaded polymeric nanoparticles. Another study indicated intranasal delivery of neuropeptide Y lowered anxiety in rats.
Anorexia nervosa
Anorexia nervosa (AN) is a common eating disorder characterized by low intake of food from fear of weight gain. Several complications are associated with this chronic disorder such as fatigue, insomnia, and low blood pressure. Intranasal administration of oxytocin in patients with AN significantly lowered food anticipation and eating concern.
Substance use disorder
Uncontrolled and continuous use of a substance, drugs or alcohol, is known as substance use disorder. Substances can interfere with neuronal signaling and potentially disrupt the brain circuit. Addiction to these substances impairs thinking, behavior, and other biological functions. Intranasal delivery of insulin is associated with improvement in brain metabolic activities and alleviate impulsivity. Opioid addiction is prevalent and associated with many substance abuse deaths. A study observed high biodistribution in the brain and reduction in opioid overdose in rats administered with naloxone-loaded lipid nanoparticles.
Post-traumatic stress disorder
Witnessing a devastating or terrifying situation can lead to post-traumatic stress disorder (PTSD). This mental health condition triggers anxiety, depression, and extreme fear with memories. Intranasal administration of temperature-sensitive hydrogels loaded with PTSD medications showed enhanced brain targeting effects and tissue distribution. Similarly, another study observed anti-PTSD effects with intranasal administration of loaded hydrogels.
Schizophrenia
Schizophrenia is a chronic mental health condition caused by changes in brain chemistry and structure. Genetics and environment are hypothesized to play a key role in development of this disorder. Research suggests impaired gene expression or chemical imbalance may impact this condition. Anxiety can increase risk of schizophrenia and symptoms include hallucinations, disorganized speech, and abnormal behavior. Davunetide (NAP) is a segment of activity-dependent neuroprotective protein (ADNP). ADNP is reported be downregulated with schizophrenia. A study observed decreased hyperactivity in mice when treated with NAP via the intranasal route.
Migraine
Migraine occurs with episodes of intense headache causing nausea and throbbing pain. Stress and hormonal changes can be a trigger migraine. A nasal spray containing sumatriptan demonstrated a significant reduction of migraine pain. Further clinical studies of intranasal administration of sumatriptan (ST) can help evaluate efficacy and safety of such delivery systems. Since its approval by the FDA in 2021, dihydroergotamine mesylate has been administered through nasal sprays to treat migraines.
Nanosystems for Intranasal Drug Delivery
Nanoparticles are drug delivery systems ranging from 1–1000 nm in diameter. Lipid-based and polymer-based nanocarriers are commonly used for nose-to-brain delivery as they exert high stability, solubility, and adherence. Exosomes and dendrimers are other potential nanocarriers. Nanosystems can be synthesized either using physical or chemical methods. A few physical methods include evaporation-condensation reaction and laser ablation. Irradiation, microemulsion, and chemical reduction are common chemical techniques to develop nanoparticles. Sonication, electroporation, and incubation are common methods to load drugs into nanocarriers.
Coating these nanosystems with mucoadhesive agents, stimulus-sensitive materials, or antibodies can enhance biocompatibility, clearance rates, specificity, and bioavailability. Penetration and absorption enhancers can significantly increase the overall efficacy of the system. Imaging studies along with measurement of drug transfer efficiency and bioavailability can further support the role of these drug delivery systems.
Lipid-based nanoparticles
Lipid-based nanoparticles (LNP) can deliver molecules with low toxicity and controlled release. Liposomes, solid lipid nanoparticles (SLN), nanostructured lipid carriers (NLC), and nanoemulsions are examples.
Liposomes are made up of phospholipids forming spherical vesicles. This property enables liposomes to exhibit high biocompatibility and biodegradability. Studies report potential application of liposomes to treat brain diseases due to increased retention and absorption in nasal cavity, and high brain biodistribution. A previous study developed a cationic liposome loaded with mRNA and green fluorescent protein (GFP). Intranasal delivery of this formulation in murine models demonstrated high brain biodistribution and expression of mRNA-GFP.
Solid lipid nanoparticles (SLNs) are made up of solid lipids forming a matrix and stabilized by surfactants. They exhibit high physical stability and remain in solid state at different temperatures. Based on a study, intranasal delivery of SLNs loaded with rivastigmine tartrate (RT) exhibited no toxicity, stability, and improved bioavailability. Sometimes burst release may occur due to rigidity and less flexibility in shape.
Nanostructured lipid carriers (NLC) are synthesized by a mixture of solid and aqueous lipids. NLC's are developed from SLNs, thus referred to as second generation LNPs. Intranasal administration of NLC loaded with curcumin (CRM) increased biodistribution and concentration in brain after emerging as a potential system for brain cancer.
Small colloidal systems made of micelles containing oil, aqueous phases, and emulsifiers are called nanoemulsions. Intranasal delivery of gel nanoemulsion loaded with temozolomide is observed to exhibit sustained release and better permeation from nose to brain to treat glioblastoma.
Polymer-based nanoparticles
Polymer-based nanoparticles can be made from either natural or synthetic sources. Nanospheres and nanocapsules are polymeric nanoparticle systems. Natural polymers can be found in the environment or human body. On the other hand, synthetic polymers do not occur naturally and are artificially developed polymers with chemical modifications. Natural polymer-based nanoparticles can be made up of chitosan, hyaluronic acid, alginate, and gelatin. Natural polymers exhibit excellent biocompatibility and biodegradability, and low toxicity. Synthetic polymer-based nanoparticles can consist of poly (glycolic acid) (PGA), poly (lactic acid) (PLA), and poly(L-lactide-co-glycolide) (PLGA).
A study evaluated chitosan nanoparticles loaded with an anti-epileptic drug, phenytoin (PHT), to treat epilepsy. Observations suggested high stability, sustained release, and bioavailability when these particles where administered via the intranasal route. Similarly, administering PLGA nanoparticles loaded lamotrigine (LTG), polymer-based nanoparticle, showed better permeation through BBB and higher bioavailability.
Exosomes
Exosomes are vesicular structures containing genetic information. Recently, exosomes are being utilized as drug carriers. These systems are observed to be stable, specific, and safe. Moreover, delivery of exosomes shows less immunogenic affects. Further surface modifications and conjugation with liposomes enhances the therapeutic effects. Based on a previous study, intranasal delivery of exosomes loaded with a Stat3 inhibitor reduced brain inflammation and slowed brain tumor growth.
Dendrimers
Dendrimers are polymeric macromolecules with a branched network similar to a tree structure. Generally, they are spherical and homogeneous. Surface charge and molecule chemistry can play crucial role with drug interaction and release. Poly(amidoamine) (PAMAM) dendrimers are the most commonly used system. A study investigated potential application of dendrimer-based formulation of haloperidol. Intranasal administration showed improved targeting, and solubility as well as high concentrations in the brain. Drugs can be loaded in dendrimers through formulation and nanoconstruct.
Importance of physiochemical properties
For drug delivery systems to bypass the blood brain barrier, modifications of physiochemical properties can enhance safety and efficacy. Size, surface charge, and lipophilicity play a major role in substance bypassing the blood brain barrier. Smaller, positively charged, or more lipophilic molecules enhance efficacy of nose-to-brain delivery. Decrease in delivery system size increases permeation. As the membrane is negatively charged, a particle with positive surface charge interacts electrostatically which enhances bioadhesion. Carriers with more lipophilicity exert better mucoadhesion and residence time. Drug system pH, solubility, and hydrogen bonding potential are other physiochemical properties which should be evaluated.
References
Drug delivery devices | Intranasal drug delivery | [
"Chemistry"
] | 3,538 | [
"Pharmacology",
"Drug delivery devices"
] |
73,537,874 | https://en.wikipedia.org/wiki/ROG%20Phone%207 | The ROG Phone 7 is a line of Android gaming smartphones made by Asus as the sixth generation of ROG smartphone series following the fifth generation ROG Phone 6. It was launched on April 13, 2023.
References
External links
- ROG Phone 7
- ROG Phone 7 Ultimate
Mobile phones introduced in 2023
Android (operating system) devices
Asus smartphones
Mobile phones with multiple rear cameras
Mobile phones with 8K video recording | ROG Phone 7 | [
"Technology"
] | 90 | [
"Mobile technology stubs",
"Discontinued flagship smartphones",
"Flagship smartphones",
"Mobile phone stubs"
] |
73,540,660 | https://en.wikipedia.org/wiki/Male%20heir | A male heir (sometimes heirs male)—usually describing the first-born son (primogeniture) or oldest surviving son of a family—has traditionally been the recipient of the residue of the estate, titles, wealth and responsibilities of his father in a patrilineal system. This system may vary by region but has ancient, perhaps prehistoric, origins, and appears in the Code of Hammurabi: "Since daughters marry strangers and thereby cut themselves off from their family, only sons inherit the paternal estate. It is they who perpetuate the family name, and preserve the ancestral property."
Absence or inadequacy of a male heir has thus been periodically problematic, resulting in succession crises, corporate upheaval, and the occasional war. The presence or absence of a male heir may alter the decision-making patterns of fathers.
See also
Heir and spare
Son preference
Birth order
Order of succession
Line of hereditary succession
Heir apparent
Estate planning
Historical inheritance systems
Partible inheritance
Patrilineality
Patronymic
Human Y-chromosome DNA haplogroup
Salic law
References
Heirs to the throne
Patriarchy
Inheritance
Legal history
Real property law
Succession
Hereditary monarchy
Order of succession
Kinship and descent
Sibling | Male heir | [
"Biology"
] | 242 | [
"Behavior",
"Human behavior",
"Kinship and descent"
] |
73,540,816 | https://en.wikipedia.org/wiki/TH-11 | The TH-11 (, lit. Sky Fire 11) is an oxidizer-rich staged combustion cycle rocket engine burning LOX and kerosene developed by Space Pioneer. The TH-11 engine features a reusable design, staged combustion cycle, wide usage of 3D printed components (>80%), and short development time, making it a notable achievement within the Chinese commercial space industry.
History
Space Pioneer proposed the TH-11 engine for its Tianlong-2 launch vehicle. Full-system hot-fire tests were completed in June 2021. The Tianlong-2 rocket successfully completed its maiden flight on April 2, 2023, achieving the targeted orbit. Powered by a single Tianhuo-11 engine in its second stage, this launch marked the engine's operational debut.
References
Rocket engines of China
Rocket engines using kerosene propellant
Rocket engines using the staged combustion cycle | TH-11 | [
"Astronomy"
] | 182 | [
"Rocketry stubs",
"Astronomy stubs"
] |
73,541,363 | https://en.wikipedia.org/wiki/Stretch-triggered%20drug%20delivery | Stretch-triggered drug delivery is a method of controlled drug delivery stimulated by mechanical forces. The most commonly used materials for stretch-triggered autonomous drug release systems are hydrogels and elastomers.
This method of drug delivery falls in the category of stimuli-responsive drug delivery systems which include pH, temperature, and redox-responsive systems. Mechanical forces occur naturally throughout the human body therefore, stretch-triggered drug delivery systems may be used to autonomously deliver medications to the body when needed. The use of autonomous drug release systems reduces outcomes such as delays in receiving treatment and inaccurate dosages. Autonomous drug release systems induced by stretch apply to drugs such as antimicrobial agents, cardiovascular medication, and anticancer drugs. Theranostic agents are also applicable to this drug delivery system, allowing for simultaneous treatment and diagnosis of diseases.
Types of Mechanical Stimuli
Compression, tension, and shear are the three main types of mechanical stimuli. Compression force is when an object experiences forces from two sides, going in opposite directions, causing it to become compacted. Tensile force is when an object experiences forces from two sides, pointing in opposite directions, causing it to stretch. Shear forces are when an object experiences forces that are parallel and are going in opposite directions. Ultrasound and magnetic fields are also examples of mechanical forces. Depending on the mechanical stimuli, a different material may improve the desired results. The human body is exposed to mechanical forces on or within bones, organs, joints, blood vessels, and cartilage.
Naturally Occurring Mechanical Stimuli
There are naturally occurring mechanical forces in the human body such as increased stress within blood vessels due to atherosclerotic plaque. The naturally occurring mechanical forces in the body enable the self-administration of medications. Motion-triggered drug delivery of anticancer therapy is achievable through the natural forces generated by organ movements. Research has been conducted on contact lenses that are pre-loaded with glaucoma medication that is released by the stretch of the contact lens during natural eye movements. The movement of joints has been used to trigger the release of antibacterial drugs into the body.
Applications
Stretch-triggered drug delivery has a variety of applications. Intracellular transfection can be achieved through drug-delivery systems that are responsive to mechanical stimuli. Drug release can be controlled by triggers due to forces experienced by the body from daily motions. Mechanical triggers have been applied to polymers to release 2-furylcarbonil derivatives which then trigger the release of molecular cargo. An application of stretch-triggered drug delivery systems is the delivery of chemotherapy triggered by esophageal stent expansion. Also, the incorporation of several drugs into stretch-triggered autonomous drug release systems is a possibility, allowing drugs to be released by the same or different signals. Stretch-triggered drug delivery is also applied to nanoparticle-loaded stretchable elastomers that release drugs due to their expanded surface area. Stretch-triggered drug delivery has been applied to the cardiovascular system through the use of drug-loaded hydrogels that lead to increased vascularization. A research study demonstrated that quinine-loaded hydrogels resulted in restricted growth of bacteria as a result of exposure to stretching.
Limitations
Due to the limited research on mechanical force-responsive drug delivery systems, the effects of mechanical forces on cells remain unclear. Current research on stretch-triggered drug delivery systems mostly involves in vitro studies, therefore, extensive in-vivo studies are required to further improve knowledge in this subject. A limitation of current technology is the release of drugs in the absence of tensile triggers and a limit of loading agents. Transdermal drug delivery systems may include stretch-triggered technology but these devices are typically used for long-term administration, making drug reloading a topic of concern. Issues of environmental impact are also a concern when it comes to transdermal drug delivery due to the material's lack of ability to biodegrade and associated electronic waste. An area of interest regarding drug delivery devices that use naturally occurring triggers is the variability of physiological parameters between people. This makes it difficult to set a standard of what will trigger this technology.
References
Drug delivery devices | Stretch-triggered drug delivery | [
"Chemistry"
] | 838 | [
"Pharmacology",
"Drug delivery devices"
] |
73,541,609 | https://en.wikipedia.org/wiki/Pause%20Giant%20AI%20Experiments%3A%20An%20Open%20Letter | Pause Giant AI Experiments: An Open Letter is the title of a letter published by the Future of Life Institute in March 2023. The letter calls "all AI labs to immediately pause for at least 6 months the training of AI systems more powerful than GPT-4", citing risks such as AI-generated propaganda, extreme automation of jobs, human obsolescence, and a society-wide loss of control. It received more than 30,000 signatures, including academic AI researchers and industry CEOs such as Yoshua Bengio, Stuart Russell, Elon Musk, Steve Wozniak and Yuval Noah Harari.
Motivations
The publication occurred a week after the release of OpenAI's large language model GPT-4. It asserts that current large language models are "becoming human-competitive at general tasks", referencing a paper about early experiments of GPT-4, described as having "Sparks of AGI". AGI is described as posing numerous important risks, especially in a context of race-to-the-bottom dynamics in which some AI labs may be incentivized to overlook security to deploy products more quickly.
It asks to refocus AI research on making powerful AI systems "more accurate, safe, interpretable, transparent, robust, aligned, trustworthy, and loyal". The letter also recommends more governmental regulation, independent audits before training AI systems, as well as "tracking highly capable AI systems and large pools of computational capability" and "robust public funding for technical AI safety research". FLI suggests using the "amount of computation that goes into a training run" as a proxy to for how powerful an AI is, and thus as a threshold.
Reception
The letter received widespread coverage, with support coming from a range of high-profile figures. As of July 2024, a pause has not been realized - instead, as FLI pointed out on the letter's one-year anniversary, AI companies have directed "vast investments in infrastructure to train ever-more giant AI systems". However, it was credited with generating a "renewed urgency within governments to work out what to do about the rapid progress of AI", and reflecting the public's increasing concern about risks presented by AI.
Eliezer Yudkowsky wrote that the letter "doesn't go far enough" and argued that it should ask for an indefinite pause. He fears that finding a solution to the alignment problem might take several decades and that any misaligned AI sufficiently intelligent might cause human extinction.
Some IEEE members have expressed various reasons for signing the letter, such as that "There are too many ways these systems could be abused. They are being freely distributed, and there is no review or regulation in place to prevent harm." One AI ethicist argued that the letter provides awareness to multiple issues such as voice cloning, but argued the letter was unactionable and unenforceable.
The letter has been criticized for diverting attention from more immediate societal risks such as algorithmic biases. Timnit Gebru and others argued that the letter was sensationalist and amplified "some futuristic, dystopian sci-fi scenario" instead of current problems with AI today.
Microsoft's CEO Bill Gates chose not to sign the letter, stating that he does not think "asking one particular group to pause solves the challenges". Sam Altman, CEO of OpenAI, commented that the letter was "missing most technical nuance about where we need the pause" and stated that "An earlier version of the letter claimed OpenAI is training GPT-5 right now. We are not and won't for some time." Reid Hoffman argued the letter was "virtue signalling", with no real impact.
List of notable signatories
Listed below are some notable signatories of the letter.
Yoshua Bengio (Canadian AI researcher, scientific director of the Montreal Institute for Learning Algorithms, and Turing Award recipient)
Stuart Russell (British computer scientist, author of Artificial Intelligence: A Modern Approach)
Elon Musk (businessman and investor, CEO of SpaceX and Tesla, owner of X Corp)
Steve Wozniak (American technology entrepreneur, co-founder of Apple)
Yuval Noah Harari (Israeli historian and philosopher, author of popular science bestseller Sapiens: A Brief History of Humankind)
Emad Mostaque (CEO of Stability AI)
Andrew Yang (American businessman and politician)
Lawrence Krauss (Canadian-American theoretical physicist and author)
John Hopfield (American scientist known for inventing associative neural networks)
Jaan Tallinn (Estonian billionaire and computer programmer, co-creator of Skype and co-founder of the Future of Life Institute)
Ian Hogarth (British investor and entrepreneur, Chair of the UK Government's AI Foundation Model Taskforce)
Evan Sharp (American internet entrepreneur and co-founder of Pinterest)
Gary Marcus (professor emeritus of psychology and neural science at New York University)
Chris Larsen (American entrepreneur and investor)
Grady Booch (American software engineer)
Max Tegmark (Swedish-American cosmologist, founder of the Future of Life Institute and author of Life 3.0)
Anthony Aguirre (American cosmologist, co-founder of the Future of Life Institute and prediction platform Metaculus)
Tristan Harris (American technology ethicist and co-founder of the Center for Humane Technology)
Danielle Allen (American political scientist)
Marc Rotenberg (president and founder of the Center for AI and Digital Policy)
Steve Omohundro (American computer scientist, CEO of Beneficial AI Research)
Aza Raskin (co-founder of the Center for Humane Technology)
Huw Price (Australian philosopher, co-founder of the Centre for the Study of Existential Risk)
Jeff Orlowski (American filmaker, director of Chasing Ice and The Social Dilemma)
Olle Häggström (Swedish mathematician and author of Here be Dragons, a book discussing the potential dangers of emerging technologies)
Raja Chatila (professor of Robotics, AI and Ethics and former Director of Research at the French National Centre for Scientific Research)
Moshe Vardi (Israeli mathematician and computer scientist)
Adam D. Smith (computer scientist at Boston University)
Daron Acemoglu (Turkish economist and professor at MIT)
Christof Koch (German neurophysiologist and computational neuroscientist)
George Dyson (American author and historian of technology)
Gillian Hadfield (legal scholar and former Senior Policy Adviser to OpenAI)
Erik Hoel (American neuroscientist, neurophilosopher, and writer)
Bart Selman (Dutch professor of computer science, co-founder of the Center for Human-Compatible Artificial Intelligence)
Tom Gruber (computer scientist and co-founder of Siri Inc.)
Robert Brandenberger (Swiss-Canadian theoretical cosmologist)
Michael Wellman (American computer scientist and fellow of the Association for the Advancement of Artificial Intelligence)
Berndt Müller (German nuclear physicist)
Alan Mackworth (Canadian AI researcher and former president of the Association for the Advancement of Artificial Intelligence)
Connor Leahy (AI safety researcher and CEO of Conjecture)
See also
Open letter on artificial intelligence (2015)
Statement on AI risk of extinction
AI takeover
Existential risk from artificial general intelligence
Regulation of artificial intelligence
PauseAI
References
External links
Official website
FAQ
Policymaking in the Pause
Existential risk from artificial general intelligence
Technology hazards | Pause Giant AI Experiments: An Open Letter | [
"Technology"
] | 1,507 | [
"Existential risk from artificial general intelligence",
"nan"
] |
73,541,787 | https://en.wikipedia.org/wiki/Daughter%20preference | Daughter preference describes human families seeking to bear and raise daughters, rather than sons.
Daughter preference is evident in contemporary Japan and Japanese-American immigrant families. South Korea has also demonstrated a measurable shift from son preference to daughter preference. Daughter preference appears at measurable levels in three Scandinavian countries: Denmark, Norway, and Sweden. One study found that a significant contributing factor to daughter preference was the "number of wife's sisters." In the matrilineal inheritance system of Malawi, daughter preference emerges if all existing children are sons.
Daughter preference or son preference is sometimes expressed by higher levels of household investment in offspring of preferred gender.
References
Gender
Human reproduction
Kinship and descent
Sociology
Matriarchy | Daughter preference | [
"Biology"
] | 141 | [
"Behavior",
"Behavioural sciences",
"Sociology",
"Gender",
"Human behavior",
"Kinship and descent"
] |
73,542,047 | https://en.wikipedia.org/wiki/Oceans%20defender | An oceans defender is a human rights and environmental activist focused on protecting the Earth's oceans. General objectives include protecting the rights of human beings as well as defending aquatic ecosystems from pollution or destruction. They generally oppose extractivism, overfishing, unreported fishing, and human rights abuses of those living on coastlines or in ocean-reliant economies.
In 2000, underwater photographer Kurt Lieber founded the Ocean Defenders Alliance to "help the ecosystem survive [an] onslaught of man-made debris and pollution." It became a 501(c)(3) nonprofit in 2002.
In 2011, Gigi Brisson formed the Ocean Elders group, a worldwide group of activists including Sylvia Earle, Richard Branson, Jackson Browne, James Cameron, Rita R. Colwell, Jean-Michel Cousteau, Wade Davis, Jane Goodall, Gerry Lopez, Catherine A. Novelli, Frederik Paulsen Jr, Bertrand Piccard, Thomas Remengesau Jr., David E. Shaw, Nainoa Thompson, Ted Turner, Don Walsh, Bob Weir, Sheila Watt-Cloutier, Neil Young, and José María Figueres.
Circa 2013, Greenpeace proliferated photographs from its Oceans Defender Tour, documenting "illegal and destructive fishing methodologies in the Gulf of Thailand." The following year, Greenpeace Southeast Asia published a list of 10 everyday tasks citizens can do to help oceans defenders.
In 2020, the World Forum of Fisher Peoples (representing 10 million small-scale fishers from 54 countries) issued a statement affirming the necessity of ocean defenders in continuing to preserve human rights for those reliant on oceans for economic benefit.
In 2022, Nigerian environmental activist Nnimmo Bassey endorsed a toolkit for "Oceans and Human Rights Defenders," detailing methods of unity and advocacy.
In 2022, Frontiers in Marine Science noted that ocean defenders face additional risk because they "are frequently from groups already subject to historical and continued structural marginalization and exclusion from decision-making. This includes small-scale fishers, Indigenous Peoples, Peoples of Colour, women and youth."
In 2023, the University of British Columbia shared a document under the title "[m]ore must be done to protect ocean defenders." The same year, Time for Kids published an interview with Sylvia Earle titled "Ocean Defender." Earle identified the largest current issue for ocean defenders as deep sea mining to create batteries for electronic vehicles, which harms deep sea ecosystems. She also denounced fish as food, stating, "[we need] to get over this idea that ocean wildlife is needed for our food security. We are now beginning to understand the high cost [to the environment] of eating fish."
See also
Land defenders
Human rights defenders
Environmental movement
Effects of climate change
Marine pollution
References
Right to a healthy environment
Environmentalism
Oceanography | Oceans defender | [
"Physics",
"Environmental_science"
] | 581 | [
"Oceanography",
"Hydrology",
"Applied and interdisciplinary physics"
] |
73,542,671 | https://en.wikipedia.org/wiki/Light%20Scattering%20Spectroscopy | Light scattering spectroscopy (LSS) is a spectroscopic technique typically used to evaluate morphological changes in epithelial cells in order to study mucosal tissue and detect early cancer and precancer.
Light scattering spectroscopy relies upon elastic scattering of photons reflected from the epithelium. Most of the signal is generated by light scattering from small intracellular structures, but larger intracellular structures, such as nuclei, also scatter light, with their relative contribution increasing in the backscatter direction. As changes in the morphology of epithelial cells are hallmarks of pre-cancer and early cancer, LSS can be used for early cancer diagnosis.
In addition to photons backscattering from epithelial cells, a major portion of photons penetrates the epithelium, reaching optically turbid connective tissue where they are scattered multiple times and partially absorbed by hemoglobin. As a result, it is not possible to measure single backscattering events directly in human tissue, with polarization gating and spatial gating well-suited for endoscopy applications.
History
Lev T. Perelman, principal scientist at MIT, and Vadim Backman, graduate student in Harvard- MIT Health Sciences and Technology program introduced LSS in 1998.
Applications
Light scattering spectroscopy has been applied for detection of precancer in many organs including esophagus, colon, urinary bladder, oral cavity, cervix, pancreatic cyst, stomach, skin, and bile duct.
References
Spectroscopy
Imaging | Light Scattering Spectroscopy | [
"Physics",
"Chemistry"
] | 314 | [
"Instrumental analysis",
"Molecular physics",
"Spectroscopy",
"Spectrum (physical sciences)"
] |
73,542,847 | https://en.wikipedia.org/wiki/Chimeric%20small%20molecule%20therapeutics | Chimeric small molecule therapeutics are a class of drugs designed with multiple active domains to operate outside of the typical protein inhibition model. While most small molecule drugs inhibit target proteins by binding their active site, chimerics form protein-protein ternary structures to induce degradation or, less frequently, other protein modifications.
Background
Small molecule drugs, compounds typically <1 kD in mass, comprise a large portion of the therapeutic market. These drugs usually operate by agonizing or antagonizing the active site on a disease-linked protein of interest, though allosteric regulation is possible. With an estimated 93% of the human proteome lacking druggable binding sites, methods have been developed to modulate protein activity through binding of any available site rather than only the active site. These drugs contain a target protein binding warhead in addition to a linker-separated active domain. This domain may recruit a second protein to the proximity, induce protease-mediated degradation, or recruit a kinase for directed phosphorylation, among other functions. These drugs expand both the mechanism of action for small molecule therapeutics and the pool of potential protein targets.
Proteolysis-targeting chimeras
Proteolysis-targeting chimeras (PROTACs) were first reported by Kathleen Sakamoto, Craig Crews, and Raymond Deshaies in 2001. A chimeric molecule consisting of ovalicin (a MetAP-2 small molecule inhibitor) and IκBα phosphopeptide (a recruiter of the SCFβ-TRCP E3 ligase complex) separated by a linker was constructed and shown to induce MetAP-2 degradation in in vitro cell models. Further study confirmed that E3 ligase-mediated ubiquitination and subsequent proteasome degradation was responsible for reduced MetAP-2 levels. Continued work on this system by Craig Crews and others has expanded the potential pool of E3 ligases and degradation targets with Arvinas Inc. founded in 2013 to bring PROTAC drugs to market. As of April 2023, Arvinas has one drug in Stage 3 clinical trials (ARV-471, an estrogen receptor degrader), and two drugs in Stage 2 clinical trials (androgen receptor degraders ARV-110 and ARV-766) for treatment of breast and prostate cancer, respectively. Arvinas released Phase 2 clinical trial results for ARV-471 in December, 2022 reporting a clinical benefit rate of 40% in CDK4/6 inhibitor-pretreated patients and an absence of dose-limiting toxicities.
Hydrophobic tag degradation
Hydrophobic tag degraders contain a binding domain in addition to a linker-separated hydrophobic moiety, such as adamantyl, to induce protein degradation. An early example of a hydrophobically tagged degrader is fulvestrant, an estrogen receptor antagonist that contains a long hydrophobic side chain that induces the degradation of the estrogen receptor. Fulvestrant has inspired the development of additional selective estrogen receptor degraders (SERDs).
As exposed hydrophobicity is characteristic of protein misfolding, the native cell proteasome may recognize and degrade proteins tagged with the hydrophobic moiety. Taavi Neklesa and Craig Crews first reported hydrophobic tag degradation in 2011 as a tool to probe protein function in conjunction with cognate HaloTag fusion proteins. This principle has also been further used to effectively degrade transcription factors (a traditionally difficult class to drug) and cancer-linked EZH2 in in vitro models. As of yet, no drug candidates have been publicly identified making use of this technology.
Additional use cases
Lysosome-targeting chimeras (LYTACs) have been developed, combining target-binding compounds or antibodies and glycopeptide ligands to stimulate the lysosomal degradation pathway. Unlike the proteasome pathway, this enables the targeted degradation of extracellular and membrane-bound proteins in addition to cytoplasmic ones. Autophagy-targeting chimeras (AUTACs) can be employed to degrade proteins as well as protein aggregates and organelles. AUTAC degradation tags are typically derived from guanine though the particular mechanism of action is still unclear. Autophagosome-tethering compounds (ATTECs) mimic this strategy, directly appending a target protein to the autophagosome membrane for degradation absent the use of a linker. Phosphorylation-inducing chimeric small molecules (PHICS) employ the warhead-linker-recruiter structure to direct phosphorylation of a given target by proximity to a desired kinase. This technique does not necessarily involve protein degradation and may instead be used to modulate protein function to direct or inhibit certain pathways. Further work in the Crews Lab has used chimeric oligonucleotides, the dCas9 protein, and chimeric small molecules to create the TRAFTAC system for generalizable transcription factor degradation.
Advantages
The ability to inhibit or modify enzyme function absent a catalytic pocket binding site target greatly expands the potentially druggable portion of the proteome. Furthermore, most classes of chimeric small molecules can act on many targets over their life cycle, lowering the effective dose compared to traditional inhibitors that act only on one protein at a time. These therapeutics provide an alternative mechanism of action that may be useful as a combination therapy in diseases where drug resistance is a concern. Chimeric drug activity is also highly dependent on distance between targeted proteins allowing effect to be effectively tuned through optimization of the linker structure.
Challenges
The existence of two or more binding domains increases the difficulty of synthesis for chimeric molecules. Each component must be discovered, optimized, and synthesized in such a way that they can be linked together, driving up cost relative to single-domain inhibitors. The large size of chimeric molecules (typically 700-1100 Da) makes effective delivery difficult and increases complexity in pharmacokinetic design. Care must be taken to ensure that the molecule is capable of passing through the cell membrane and subsisting long enough to have therapeutic effect. Additionally, protein-protein ternary complexes are generally unstable, adding to the difficulty of chimeric drug design
References
Medicinal chemistry | Chimeric small molecule therapeutics | [
"Chemistry",
"Biology"
] | 1,291 | [
"Biochemistry",
"nan",
"Medicinal chemistry"
] |
73,543,019 | https://en.wikipedia.org/wiki/Persistence%20barcode | In topological data analysis, a persistence barcode, sometimes shortened to barcode, is an algebraic invariant associated with a filtered chain complex or a persistence module that characterizes the stability of topological features throughout a growing family of spaces. Formally, a persistence barcode consists of a multiset of intervals in the extended real line, where the length of each interval corresponds to the lifetime of a topological feature in a filtration, usually built on a point cloud, a graph, a function, or, more generally, a simplicial complex or a chain complex. Generally, longer intervals in a barcode correspond to more robust features, whereas shorter intervals are more likely to be noise in the data. A persistence barcode is a complete invariant that captures all the topological information in a filtration. In algebraic topology, the persistence barcodes were first introduced by Sergey Barannikov in 1994 as the "canonical forms" invariants consisting of a multiset of line segments with ends on two parallel lines, and later, in geometry processing, by Gunnar Carlsson et al. in 2004.
Definition
Let be a fixed field. Consider a real-valued function on a chain complex compatible with the differential, so that whenever in . Then for every the sublevel set is a subcomplex of K, and the values of on the generators in define a filtration (which is in practice always finite):
.
Then, the filtered complexes classification theorem states that for any filtered chain complex over , there exists a linear transformation that preserves the filtration and brings the filtered complex into so called canonical form, a canonically defined direct sum of filtered complexes of two types: two-dimensional complexes with trivial homology and one-dimensional complexes with trivial differential . The multiset of the intervals or describing the canonical form, is called the barcode, and it is the complete invariant of the filtered chain complex.
The concept of a persistence module is intimately linked to the notion of a filtered chain complex. A persistence module indexed over consists of a family of -vector spaces and linear maps for each such that for all . This construction is not specific to ; indeed, it works identically with any totally-ordered set.
A persistence module is said to be of finite type if it contains a finite number of unique finite-dimensional vector spaces. The latter condition is sometimes referred to as pointwise finite-dimensional.
Let be an interval in . Define a persistence module via , where the linear maps are the identity map inside the interval. The module is sometimes referred to as an interval module.
Then for any -indexed persistence module of finite type, there exists a multiset of intervals such that , where the direct sum of persistence modules is carried out index-wise. The multiset is called the barcode of , and it is unique up to a reordering of the intervals.
This result was extended to the case of pointwise finite-dimensional persistence modules indexed over an arbitrary totally-ordered set by William Crawley-Boevey and Magnus Botnan in 2020, building upon known results from the structure theorem for finitely generated modules over a PID, as well as the work of Cary Webb for the case of the integers.
References
Computational topology
Representation theory
Algebraic topology
Applied mathematics
Data science | Persistence barcode | [
"Mathematics"
] | 659 | [
"Computational topology",
"Applied mathematics",
"Computational mathematics",
"Algebraic topology",
"Fields of abstract algebra",
"Topology",
"Representation theory"
] |
73,544,119 | https://en.wikipedia.org/wiki/Lemino | is a Japanese video on demand over-the-top streaming service operated by NTT Docomo. From its establishment in 2011 until 2022, it was owned 70% by Avex. It operated as a subscription video on demand (SVOD) service under the name from 2011 to 2013, from 2013 to 2015, and dTV from 2015 to 2023, before becoming partially an ad-supported video on demand (AVOD) service.
In 2016, it had the largest market share of 24.1% in Japan, but in 2022, its share had decreased to 4.2%.
In addition to Lemino, Docomo operates a sister service called d-anime Store, which is a SVOD service specializing in anime content. It has 2.5 million subscribers.
History
In April 2009, Avex Entertainment and NTT Docomo announced the launch of a mobile phone exclusive broadcasting station called BeeTV for Docomo users, which was set to start broadcasting on May 1, 2009. This project was announced in October 2008. BeeTV is operated by a joint venture company called Avex Broadcasting & Communications Inc., in which Avex holds a 70% stake and Docomo holds a 30% stake. The company was established on April 10, 2009. In March, 2011, it expanded its service to Android smartphones with a monthly subscription fee of 315 yen.
On December 18, 2011, NTT Docomo launched a subscription video-on-demand (SVOD) service called (d-video or Video Store) within their online store d-market, along with music and ebook distribution services. The service was available exclusively for Docomo's mobile phone users and cost 525 yen per month. However, in February 2012, an Android app was made available for the service.
The number of members for Video Store surpassed 1 million on April 24, 2012, 2 million on July 21, 2012, 3 million on November 25, 2012, and 4 million on March 19, 2013.
On January 30, 2013, VIDEO Store was renamed to (d-video).
Starting from February 26, 2014, d-market services, including d-video, became available for use on smartphones and tablets from companies other than Docomo.
On April 22, 2015, Avex and Docomo announced that d-video would be renamed to dTV starting from the same day. As part of its renewal, dTV introduced a zapping user interface. Upon launching the app, a video immediately starts playing, and the channels arranged vertically can be changed by flicking on a smartphone or using a TV remote control, allowing users to begin watching something without actively searching for it. This change has made it easier for users to find video content and improved overall convenience.
As a result of this renewal, the cancellation rate significantly decreased and the number of subscribers increased. On March 27, 2016, the number of dTV users exceeded 5 million, making it the largest SVOD service in Japan, significantly surpassing Video Pass by KDDI with 1 million users, UULA by Avex and SoftBank with 1.24 million users, and Hulu Japan by Nippon TV with 1 million users.
dTV started supporting Chromecast in May 2015, Fire TV in March 2016, and Apple TV in June 2016.
On June 30, 2018, dTV released Punk Samurai Kirarete-sōrō, a movie produced solely by the video streaming service. This marked the first time a Japanese movie produced by a streaming service was released in theaters. Originally planned as a streaming exclusive, the project was later given a nationwide theatrical release in 300 cinemas. However, the box office revenue was only 300 million yen.
According to the market research firm GEM Partners, as of 2016, dTV had a domestic share of 24.1%, overwhelmingly ranking first. However, in 2017, the share decreased to 18.1%, in 2019 to 13.7%, and in 2022 to 4.2%.
In December 2021, Docomo announced that it would be changing the URL of dTV from video.dmkt-sp.jp to dtv.docomo.ne.jp. However, this change was not implemented until the renewal to Lemino.
The financial results for the fiscal year ending March 2022 for the company that operates dTV showed a significant decline in revenue and profit, with sales of 11.2 billion yen (a decrease of 6.7% from the previous year) and operating profit of 460 million yen (a decrease of 70.1% from the previous year). Over the past two years, sales have decreased by approximately 20% and operating profit has decreased by over 80%. In light of these challenging business conditions, in January 2023, Avex and Docomo dissolved their joint venture, with Avex selling all of its shares to Docomo, which previously owned a 30% stake in the company while Avex held a 70% stake.
On March 6, 2023, NTT Docomo announced that it would be replacing its dTV video streaming service with an ad-supported video on demand (AVOD) service called Lemino from April 12. Lemino will have two plans: a free, ad-supported plan and a premium plan called "Lemino Premium" for 990 yen per month. While dTV had a strong lineup of music content, Lemino has expanded its offerings to include original works, anime, and Korean dramas, resulting in a library of nearly 180,000 titles, which is slightly less than double its previous count. In an effort to reach a broader range of customers beyond Docomo's telecommunications subscribers, the Lemino brand dropped the "d" from its name, which was associated with Docomo.
During a press conference on the 6, Docomo executive officer Tomo Kobayashi stated, "The competition in the video streaming service market has become intense, and relying solely on low prices has caused us to lose some of our presence. We want to introduce something new." According to Gem Partners' estimates, dTV held a market share of 4.2% in Japan's subscription video streaming services in 2022. Domestic capital services are undergoing consolidation, and in January of this year, Z Holdings and Yahoo! Japan announced the end of their video streaming service, Gyao!. In February, U-Next, which held the second-largest market share domestically, announced the acquisition of the operating company of Paravi, in which TBS Television and TV Tokyo had invested.
Docomo announced on April 24, 2023 that it has formed a business alliance with Yoshimoto Kogyo Holdings in the entertainment industry. On May 1, they established a joint venture company called NTT Docomo Studio & Live to produce programs, discover idol groups, and hold live concerts. The new company plans to distribute its programs on the Lemino and also aims to sell the developed idols and programs overseas.
See also
d-anime Store
References
External links
NTT Docomo
Subscription video on demand services
Japanese film websites
Internet television streaming services
Subscription video streaming services
Android (operating system) software
IOS software
PlayStation 4 software
PlayStation 5 software | Lemino | [
"Technology"
] | 1,455 | [
"Members of the Conexus Mobile Alliance",
"NTT Docomo"
] |
73,545,085 | https://en.wikipedia.org/wiki/Symbols%20of%20grouping | In mathematics and related subjects, understanding a mathematical expression depends on an understanding of symbols of grouping, such as parentheses (), square brackets [], and braces {} (see note on terminology below). These same symbols are also used in ways where they are not symbols of grouping. For example, in the expression 3(x+y) the parentheses are symbols of grouping, but in the expression (3, 5) the parentheses may indicate an open interval.
The most common symbols of grouping are the parentheses and the square brackets, and the latter are usually used to avoid too many repeated parentheses. For example, to indicate the product of binomials, parentheses are usually used, thus: . But if one of the binomials itself contains parentheses, as in one or more pairs of () may be replaced by [], thus: . Beyond elementary mathematics, [] are mostly used for other purposes, e.g. to denote a closed interval, or an equivalence class, so they appear rarely for grouping.
The usage of the word "brackets" varies from country. In the United States, the term denotes [], known elsewhere as "square brackets". In the United Kingdom and many other English-speaking countries, "brackets" means (), known in the US as "parentheses" (singular "parenthesis"). That said, the specific terms "parentheses" and "square brackets" are generally understood everywhere and may be used to avoid ambiguity.
The symbol of grouping knows as "braces" has two major uses. If two of these symbols are used, one on the left and the mirror image of it on the right, it almost always indicates a set, as in , the set containing three members, , , and . But if it is used only on the left, it groups two or more simultaneous equations.
There are other symbols of grouping. One is the bar above an expression, as in the square root sign in which the bar is a symbol of grouping. For example is the square root of the sum. The bar is also a symbol of grouping in repeated decimal digits. A decimal point followed by one or more digits with a bar over them, for example 0., represents the repeating decimal 0.123123123... .
A superscript is understood to be grouped as long as it continues in the form of a superscript. For example if an x has a superscript of the forma+b, the sum is the exponent. For example: x2+3, it is understood that the 2+3 is grouped, and that the exponent is the sum of 2 and 3.
These rules are understood by all mathematicians.
The associative law
In most mathematics, the operations of addition and multiplication are associative.
The associative law for addition, for example, states that . This means that once the associative law is stated, the parentheses are unnecessary and are usually omitted. More generally, any sum, of any number of terms, can be written without parentheses and any product, of any number of factors, can be written without parentheses.
Hierarchy of operations
The "hierarchy of operations", also called the "order of operations" is a rule that saves needing an excessive number of symbols of grouping. In its simplest form, if a number had a plus sign on one side and a multiplication sign on the other side, the multiplication acts first. If we were to express this idea using symbols of grouping, the factors in a product. Example: 2+3×4 = 2 +(3×4)=2+12=14.
In understanding expressions without symbols of grouping, it is useful to think of subtraction as addition of the opposite, and to think of division as multiplication by the reciprocal.
References
Mathematical notation | Symbols of grouping | [
"Mathematics"
] | 779 | [
"nan"
] |
73,545,984 | https://en.wikipedia.org/wiki/Reproductive%20privilege | Reproductive privilege is a form of social privilege that describes people who have been able to regenerate themselves biologically and produce new generations with an unremarkable level of difficulty. People with a reproductive disadvantage (including those with infertility, recurrent miscarriages, involuntary childlessness, or other forms of reproductive loss or lack) use the term in reference to the variant levels of ease or difficulty with which people can become/stay pregnant and carry to term (if female) or father a living child (if male). The concept of reproductive difference is controversial and discussion of reproductive privilege is fraught with the social and sociological conflicts that are common to public discourse about children and families.
The concept of reproductive privilege, like the related concept of ableism, identifies a human capacity that many take for granted but that is not universally accessible. Reproduction is limited to people with certain bodies, at certain times of their lives, usually with certain baseline levels of physical and mental health. In addition, reproductive behaviors have traditionally occurred within a certain social and economic framework that may be inaccessible to some people for any number of reasons. A stereotypical post-menopausal 19th century spinster who still yearns for children might see a young and beautiful bride as having "reproductive privilege" in that she has an opportunity for and strong likelihood of reproduction. Heterosexual couples have a reproductive advantage over homosexual couples. An infertile couple that successfully adopted arguably has two forms of reproductive privilege, one compared to the biological parents who were not financially or emotionally equipped to raise an infant to adulthood, and two, to other adoption-seeking parents who have not been able to successfully arrange an adoption. While the most common use of reproductive privilege is in regards to fertility versus infertility, it can also describe the comfort of a privileged ignorance of miscarriage, stillbirth and infant death. In the words of one writer, "If people talking about their grief, their loss, their lack makes you feel uncomfortable and defensive: well, that’s privilege...You're entitled to your happiness. Just as we are entitled not to censor our sadness."
Opponents of the concept argue that it commodifies children.
See also
Stratified reproduction
Infertility and childlessness stigmas
References
Human reproduction
Kinship and descent
Social privilege
Feminist terminology
Identity politics
Majority–minority relations | Reproductive privilege | [
"Biology"
] | 476 | [
"Behavior",
"Human behavior",
"Kinship and descent"
] |
73,546,291 | https://en.wikipedia.org/wiki/Wave%20run-up | Wave run-up is the height to which waves run up the slope of a revetment, bank or dike, regardless of whether the waves are breaking or not. Conversely, wave run-down is the height to which waves recede. These heights are always measured vertically (and not along the slope). The wave run-up height, denoted by , , or , is a very important parameter in coastal engineering as, together with the design highest still water level, it determines the required crest height of a dike or revetment.
History
The first scientific measurements of wave run-up were carried out by the Lorentz Committee in preparation for the works to close off the Zuiderzee.
The Committee measured the wave height and wave run-up at various locations in 1920, but established that state of the art methods for measuring waves in the field during storms were inadequate. As a result, scale tests were also undertaken, but these also proved to be of very limited efficacy due to the fact that only regular waves (idealised, periodic waves with constant amplitude and a fixed time period between successive wave crests, following a sinusoidal pattern) could be modelled at the time.
The methods and technology available to the committee at the time did not permit model testing of the more realistic and complex irregular waves (consisting of varying heights, periods and directions), which provide a more accurate representation of the actual conditions faced by coastal structures and shorelines.
It was found, however, that the depth in front of the dike is very important for wave run-up and that, at least for the range of observations in the committee's measurements, the slope ratio does not play a major role. Nearly all dikes in the Netherlands at that time had a slope of 1:3.
Current knowledge indicates that during storms and on gentle coastal slopes, the significant wave height is approximately half the water depth. This relationship appears to be accurate, and the observation is more pronounced for slopes around 1:3.
This research was continued during the Zuiderzee Works, and eventually led to the (old) Delft formula for wave run-up:
in which:
is the run-up,
is the (regular) wave height at the toe and
is the slope of the construction under consideration.
This formula proved to be generally applicable for smooth slopes and relatively steep (storm) waves. Subsequently, it was discovered that longer (swell) waves resulted in higher run-up. To account for this, the wave period was incorporated into the formula using the Iribarren number, , leading to the development of Hunt's Formula:
This formula was also valid for regular waves. The Old Delft Formula and Hunt's Formula are identical for waves with a steepness of 1/64, or about 2%. For higher values of , Hunt's formula has a limit value:
.
van der Meer, TAW and continuing development of formulae
In 1988, van der Meer provided formulae for wave run-up on rubble mound breakwaters, based on tests with rock-armoured straight slopes. He also introduced a notional permeability factor for the structure. This factor also accounts for the effect of the pore volume. Defining at the run-up level of exceedance probability , the formula, valid for and head-on waves, is:
The term reaches a constant maximum value equal to in the case of permeable structures, i.e., . This corresponds to the region of surging waves, where there is no real wave breaking and where wave steepness and slope angle do not influence the run-up. The coefficients and are presented in the table below:
The values of the coefficients highlight the considerable variability of the run-up level from one wave to another in irregular seas. For run-up levels on smooth slopes, work in the Netherlands by the Technische Adviescommissie voor de Waterkeringen (English: Technical Advisory Committee on water Defences) in 1974 discussed the reduction in run-up due to different types of surface roughness.
Irregular waves
In practical scenarios, waves are irregular, consisting of a combination of waves with varying heights, periods, and directions. These waves are typically analysed using statistical methods and spectral analysis, providing a more accurate representation of the actual conditions faced by coastal structures and shorelines. Consequently, it is not possible to define a single wave run-up value. Instead, a wave run-up with a specific probability of exceedance is used, typically set at 2%. This wave run-up represents the height exceeded by 2% of the waves in a wave field.
Research indicates that wave run-up follows a Rayleigh distribution, similar to the waves themselves. A probability of exceedance value has been chosen that is small enough to prevent overtopping waves from causing damage to the inner slope. The 2% value has been adopted internationally and was arbitrarily selected by the Dutch Waterloopkundig Laboratorium shortly before 1940. Considering the function, 1% or 5% could have also been possible. The choice of 2% was based on the duration of experimental designs, as a complete trial could be conducted in half a day.
In 1972, Jurjen Battjes, commissioned by the Dutch Technical Advisory Committee for Flood Defences, summarised the available research and provided a solid theoretical foundation. This work led to an improved version of Hunt's Formula, which explicitly included parameters for the angle of incidence of the waves, the effect of a berm, and the slope's roughness. However, the available experimental data on roughness and the berm were insufficient to establish a definitive formula.
Subsequent research was conducted in the following years, with an emphasis on wave overtopping as a more indicative factor for dike height than wave run-up. This research ultimately resulted in a Technical Report in 2002 by the Dutch organisation, TAW. The wave run-up formula mentioned in this report remains in use, and the EurOtop manual has adopted it. The scope of validity has been further expanded in the EurOtop manual, featuring modified formulas.
Modern wave run-up formulas
The EurOtop manual provides a general formula (Formula 1.4 in the manual) for wave run-up:
with a maximum value around 3. The Iribarren number is then used based on the period determined using the first negative moment of the wave spectrum. Additionally, is the reduction coefficient for the factors described below.
The following equation is valid:
in which:
is the reduction by the berm. A berm is especially effective when it is placed on still water level (i.e. design water level). For a typical Dutch dike (slope 1:3, steep waves) the following equation is valid: , in which is the width of the berm. The acceptable range for this is .
is a reduction for obliquely approaching waves, , in which is the approach angle of the waves in degrees (0° being a perpendicular approach)
is the effect of roughness. One may use the following table for this factor:
{| class="wikitable" style="float:left;"
! Reference type
!
|-
| Concrete||1.0
|-
| Asphalt|| 1.0
|-
| Concrete blocks||1.0
|-
| Grass ||1.0
|-
| Basaltic columns ||0.90
|-
| Basalton ||0.90
|-
| Hydroblock, Haringmanblok ||0.90
|-
| Open stone asphalt ||0.90
|-
| Hillblock, Ronataille ||0.70 - 0.80
|-
| Single layer of armourstone ||0.70
|-
| Double layer of armourstone ||0.55
|}
A range is provided for Hillblock and Ronataille materials, as their reduction coefficient is dependent on wave height. A similar phenomenon occurs with grass. When subjected to high waves, natural grass becomes very smooth, resulting in a reduction coefficient . However, for smaller waves — approximately or less — natural grass tends to be much rougher. In such cases, one may opt for a reduction coefficient of below 1.0.
When dealing with short-crested waves, the highest run-up is caused by head-on waves (those with an angle of incidence, ) and equates to the run-up for long-crested waves. For smooth slopes, the run-up decreases slightly with . The run-down typically ranges between a third and a half of the run-up. For breakwaters and revetments constructed with rock armour, the maximum run-down level may indicate the minimum downward extension of the primary armour, and a potential upper level for introducing a berm with a smaller armour size.
Wave run-down
For wave run-down there is a similar formula:
Flood mark
Following storm events, a layer of floating debris, known as the flood mark or flotsam, often remains on the slope. This tide mark indicates the maximum wave run-up during the preceding storm. As the flood mark is situated near the height of maximum wave run-up and water levels are generally well-documented by nearby tide stations, it is straightforward to calculate the Ru2% of the storm by subtracting the observed storm surge level from the flood mark level.
In the past, authorities in the Netherlands systematically recorded these observations for most dikes, resulting in a collection of flood mark heights for each dike section. The statistics of flood mark heights can be utilised to determine dike height, which should comprise the design water level plus a safety height (freeboard). The freeboard at the design water level must be equal to the maximum permissible wave run-up.
For a dike with an acceptable load exceedance probability per year, such as 1/500 (as with the temporary dike reinforcement in the Oosterschelde), it is necessary to determine the 1/500 wave run-up. This can be calculated if the 1/500 wave height at the toe of the dike is known. However, this value is rarely measured and must be determined using a computational model, such as SWAN. In many instances, this process can be challenging and prone to errors.
By analysing flood mark heights, which involves simply plotting the data on logarithmic paper, it is possible to directly obtain values such as the 1/500 wave run-up, and consequently the required safety height. An example of this can be observed in the accompanying photo of the run-up and flood mark lines at a dike along the Bathpolder in Zeeland. The photo shows two flood mark lines, which represent the wave run-up of two subsequent storms (on October 12, 2009, with water levels at and above mean sea level) in the Bathpolder. In the foreground, there is a slope with Haringman blocks, while the background features a slope of Elastocoast. The wave height during these storms was approximately . The wave run-up was above the storm surge level on the Elastocoast, and above the storm surge level on the Haringman blocks. The slope gradient here is 1:4.2. As a Haringman block measures exactly , the run-up can be assessed in this photo. Subsequent analysis reveals that the reduction coefficient γf for Haringman blocks here is 1.0, and for Elastocoast, it is 0.8.
Wave run-up simulation
To assess the safety of a dike and the durability of its grass cover, particularly on the sea or river side, a wave run-up simulator can be employed. The wave conditions for which a dike is designed are infrequent, and the strength of grass coverings varies. These dike conditions can be replicated in-situ using a wave run-up simulator, allowing the manager of the relevant flood defence system to determine if the grass cover is strong enough to withstand expected waves under extreme conditions.
During these tests, the wave run-up simulator is placed on the outer slope and continuously filled with water at a constant flow rate. The flaps at the bottom of the simulator can be opened to varying extents, enabling the simulation of different wave run-up volumes.
The wave run-up simulator is one method for assessing the strength of the grass cover. Another approach involves using a sod puller, which can determine the tensile strength of a sod and allows conversion of this tensile strength by an engineer into a strength under load caused by wave run-up. In addition to simulating wave run-up, the simulation of wave impacts and wave overtopping can be achieved using specifically designed generators and simulators.
Note
Wave run-up should not be confused with wave set-up (an increase in water level due to known waves) or with wind setup (storm surge, an increase in water level due to the driving force of wind).
References
General reference
; ; ; ; ; ; ; ; (2018): EurOtop. Manual on wave overtopping of sea defences and related structures. An overtopping manual largely based on European research, but for worldwide application, Rijkswaterstaat & Environment Agency
Civil engineering
Coastal engineering
Hydraulic engineering | Wave run-up | [
"Physics",
"Engineering",
"Environmental_science"
] | 2,722 | [
"Hydrology",
"Coastal engineering",
"Physical systems",
"Construction",
"Hydraulics",
"Civil engineering",
"Hydraulic engineering"
] |
67,728,208 | https://en.wikipedia.org/wiki/Chiara%20Marletto | Chiara Marletto is an Italian theoretical physicist at Wolfson College, Oxford. She is a pioneer in the field of constructor theory, counterfactuals and a generalization of the quantum theory of information.
Life
Marletto grew up in Turin. She graduated from the Polytechnic University of Torino, and the University of Oxford, where she studied with Artur Ekert.
Together with David Deutsch, she has developed constructor theory. She is a member of New Frontiers Quantum Hub.
Works
References
Further reading
Quantum computers are revealing an unexpected new theory of reality, New Scientist
Reconstructing physics: The universe is information, New Scientist
External links
Constructor Theory website
Chiara Marletto Interview Part One, 7 October 2020
Academics of the University of Oxford
21st-century Italian physicists
Italian women physicists
Scientists from Turin
Quantum information scientists
Theoretical physicists
Living people
Year of birth missing (living people)
Italian expatriates in England | Chiara Marletto | [
"Physics"
] | 193 | [
"Theoretical physics",
"Theoretical physicists"
] |
67,729,175 | https://en.wikipedia.org/wiki/Simultaneous%20hermaphroditism | Simultaneous hermaphroditism is one of the two types of hermaphroditism, the other type being sequential hermaphroditism. In this form of hermaphroditism an individual has sex organs of both sexes and can produce both gamete types even in the same breeding season.
The distinction between simultaneous hermaphroditism and sequential hermaphroditism is not always clear. But unlike sequential hermaphrodites, simultaneous hermaphrodites are both male and female at sexual maturity. Also sex determination does not apply to simultaneous hermaphrodites (except in species with mix mating systems). In simultaneous hermaphrodites, self-fertilization is possible in some species, where in others it is absent.
Evolution
The evolution of anisogamy possibly contributed to the evolution of Simultaneous hermaphroditism. It is known that simultaneous hermaphroditism that exclusively reproduces through self-fertilization has evolved many times in plants and animals, but it might not last long evolutionarily.
The primary model explaining the evolution of simultaneous hermaphroditism from gonochorism in animals is the low density model. This model explains simultaneous hermaphroditism as a reproductive adaptation to limited mating opportunities. This is advantageous to simultaneous hermaphrodites that can self-fertilize, because they are able to reproduce even if they fail to find a sexual partner. The low density model is helpful for understanding the development of simultaneous hermaphroditism in many animal species. For example, in crustaceans simultaneous hermaphroditism can be found in groups that are sessile or live in environments with limited mating opportunities.
Plants
Most plants are simultaneous hermaphrodites with it occurring in 80% of angiosperms.
Animals
Simultaneous hermaphroditism is one of the most common sexual systems in animals. The majority of Cocculinoidea are simultaneous hermaphrodites and it occurs in over 67% of coral species.
References
Sexual system
Reproductive system
Sexual reproduction | Simultaneous hermaphroditism | [
"Biology"
] | 438 | [
"Behavior",
"Reproductive system",
"Reproduction",
"Sex",
"Sexual system",
"Organ systems",
"Sexual reproduction",
"Sexuality"
] |
67,730,272 | https://en.wikipedia.org/wiki/Institute%20of%20Solid%20State%20Chemistry%20and%20Mechanochemistry | Institute of Solid State Chemistry and Mechanochemistry of the Siberian Branch of the RAS () is a research institute in Novosibirsk, Russia. It was founded in 1944.
History
Institute of Solid State Chemistry and Mechanochemistry is one of the oldest scientific institutes in Siberia. It was founded in 1944 as the Chemical and Metallurgical Institute. Five years later, thanks to the institute, a ceramic pipe plant was launched in Dorogino. Later, the institute became part of the Siberian Branch of the USSR Academy of Sciences.
In 1964, the scientific organization was renamed the Institute of Physicochemical Principles of Mineral Raw Materials Processing, and in 1980, it was renamed the Institute of Solid State Chemistry and Mineral Raw Materials Processing. In 1997, the institute was renamed the Institute of Solid State Chemistry and Mechanochemistry.
Locations
The institute is located in Tsentralny District (Frunze Street 13) and Akademgorodok.
Branches
Kemerovo Division of Institute of Solid State Chemistry and Mechanochemistry of the Siberian Branch of the RAS
External links
Институт химии твердого тела и механохимии СО РАН. ГПНТБ СО РАН.
Механохимия нас связала: ИХТТМ отмечает 75-й день рождения. Наука в Сибири.
Institute of Solid State Chemistry and Mechanochemistry of the Siberian Branch of the RAS. The SB RAS Portal.
Research institutes in Novosibirsk
Solid-state chemistry
Research institutes established in 1944
1944 establishments in the Soviet Union
Research institutes in the Soviet Union | Institute of Solid State Chemistry and Mechanochemistry | [
"Physics",
"Chemistry",
"Materials_science"
] | 389 | [
"Condensed matter physics",
"nan",
"Solid-state chemistry"
] |
67,730,577 | https://en.wikipedia.org/wiki/Suedono%20Tile%20Kiln | The is an archaeological site with the ruins of a Kamakura period kiln, located in the Numagami neighborhood of the city of Misato, Saitama Prefecture in the Kantō region of Japan. It was designated a National Historic Site of Japan in 1931.
Overview
roof tiles made of fired clay were introduced to Japan from Baekche during the 6th century along with Buddhism. During the 570s under the reign of Emperor Bidatsu, the king of Baekche sent six people to Japan skilled in various aspects of Buddhism, including a temple architect. Initially, tiled roofs were a sign of great wealth and prestige, and used for temple and government buildings. The material had the advantages of great strength and durability, and could also be made at locations around the country wherever clay was available.
The Suedono site is located in the northwestern part of the prefecture, in the southwestern part of the Honjō Plateau, surrounded by rolling hills. In 1929, an archaeological excavation of the kiln dated it to the Kamakura period from the tile shards found, and due to its good preservation, and the kiln ruins were designated as a National Historic Site in 1931. In an excavation conducted in 1989 , the remains of four tile kilns were found, in the form of flat kilns made from hollowed out ground, with a length of 3.3 meters, and a width of 1.1 meters and depth of 1.2 meters. The roof tiles produced in this tile kiln were transported to Kamakura and were used on important temples and shrines. In particular, it was discovered that tiles from this site were used at the now-extinct temple of Yōfuku-ji in Nikaidō, Kamakura.
The site is located a 30-minute walk from the "Anashi" bus stop on the Musashi Kanko Bus from Honjō Station on the JR East Takasaki Line.
See also
List of Historic Sites of Japan (Saitama)
References
External links
Misato City tourist information home page
Misato, Saitama (city)
Historic Sites of Japan
History of Saitama Prefecture
Musashi Province
Kamakura period
Japanese pottery kiln sites | Suedono Tile Kiln | [
"Chemistry",
"Engineering"
] | 443 | [
"Kilns",
"Japanese pottery kiln sites"
] |
67,731,326 | https://en.wikipedia.org/wiki/Sotrovimab | Sotrovimab, sold under the brand name Xevudy, is a human neutralizing monoclonal antibody with activity against severe acute respiratory syndrome coronavirus 2, known as SARS-CoV-2. It was developed by GlaxoSmithKline and Vir Biotechnology, Inc. Sotrovimab is designed to attach to the spike protein of SARS-CoV-2.
The most common side effects include hypersensitivity (allergic) reactions and infusion-related reactions.
Although Sotrovimab was used world-wide against SARS-CoV-2, including in the United States under an FDA emergency use authorization (EUA), the FDA canceled the EUA in April 2022 due to lack of efficacy against the Omicron variant.
Medical uses
In the European Union, sotrovimab is indicated for the treatment of COVID-19 in people aged twelve years of age and older and weighing at least who do not require supplemental oxygen and who are at increased risk of the disease becoming severe.
Sotrovimab is given by intravenous infusion, preferably within 5 days of onset of COVID-19 symptoms.
Development and mechanism of action
Sotrovimab's development began in December 2019, at Vir Biotechnology when Vir scientists first learned of the initial COVID-19 outbreak in China. Vir subsidiary Humabs BioMed had already compiled a library of frozen blood samples from patients infected with viral diseases, including two samples from patients infected with SARS-CoV-1. Vir scientists obtained samples of the novel SARS-CoV-2 virus and mixed them with various antibodies recovered from the old SARS-CoV-1 blood samples. The objective was to identify antibodies effective against both SARS-CoV-1 and SARS-CoV-2. This would imply that the antibodies were targeting highly conserved sequences and in turn would be more likely to remain effective against future variants of SARS-CoV-2. In April 2020, Lawrence Berkeley National Laboratory conducted a X-ray crystallography study at Vir's request to investigate how such antibodies bind to SARS-CoV-2 at the molecular level. The Berkeley Lab data helped Vir identify candidates for further study, and Vir eventually settled on a single candidate antibody, S309. Vir collaborated with GlaxoSmithKline to make various refinements to S309, resulting in sotrovimab.
Sotrovimab has been engineered to possess an Fc LS mutation (M428L/N434S) that confers enhanced binding to the neonatal Fc receptor resulting in an extended half-life and potentially enhanced drug distribution to the lungs.
Sotrovimab has demonstrated activity via two antiviral mechanisms in vitro, antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP).
Clinical efficacy
The pivotal COMET-ICE study is an ongoing, randomized, double-blind, placebo-controlled study to assess the safety and efficacy of sotrovimab in adults with confirmed COVID-19 (mild, early disease with less than five days of symptoms) at risk of disease progression.
An interim analysis of this study reported that sotrovimab reduced the risk of hospitalization for more than 24 hours or death by 85% compared with placebo. Overall 1% of people receiving sotrovimab died or required hospitalization for more than 24 hours compared to 7% of people treated with placebo. The study is ongoing and preliminary results have been published in the New England Journal of Medicine.
The full analysis of the COMET-ICE trial was published in JAMA and it showed that sotrovimab reduced risk of hospitalization for more than 24 hours or death by 79% compared to placebo (1% for sotrovoimab group and 6% for the placebo group). The trial involved 1057 participants and took place before the omicron variant was prevalent.
Manufacturing
Sotrovimab is a biologic product which takes six months to manufacture in living cells. It is produced in Chinese hamster ovary cells. At product launch in May 2021, sotrovimab's active pharmaceutical ingredient was produced by WuXi Biologics in China and sent to a GlaxoSmithKline plant in Parma, Italy for further processing into the finished product. In January 2022, the spread of the SARS-CoV-2 Omicron variant began to render other monoclonal antibodies obsolete and caused global demand for sotrovimab to skyrocket. In response, Vir and GlaxoSmithKline announced they were working with Samsung Biologics on manufacturing sotrovimab at an additional site in South Korea.
Society and culture
Economics
In 2021, the United States government agreed to purchase 1.5 million doses of the drug at $2,100 per dose.
Legal status
In May 2021, the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) completed its review on the use of sotrovimab for the treatment of COVID-19. It concluded that sotrovimab can be used to treat confirmed COVID-19 in adults and adolescents (aged twelve years and above and weighing at least ) who do not require supplemental oxygen and who are at risk of progressing to severe COVID-19. In December 2021, sotrovimab was authorized for use in the EU.
In May 2021, the U.S. Food and Drug Administration (FDA) issued an emergency use authorization (EUA) for sotrovimab for the treatment of mild-to-moderate COVID-19 in people aged twelve years and above weighing at least with positive results of direct SARS-CoV-2 viral testing and who are at high risk for progression to severe COVID-19, including hospitalization or death.
In August 2021, sotrovimab was granted provisional approval for the treatment of COVID-19 in Australia.
In September 2021, sotrovimab was granted special exception authorization in Japan.
In December 2021, the Medicines and Healthcare products Regulatory Agency (MHRA) in the United Kingdom approved sotrovimab for use in people aged twelve years of age and over who weigh more than .
In March 2022, the FDA withdrew the emergency use authorization for sotrovimab in multiple states due to the high frequency of the Omicron BA.2 sub-variant and data showing that the authorized dose of sotrovimab is unlikely to be effective against that sub-variant. In April 2022, the FDA withdrew the emergency use authorization for sotrovimab.
Research
Sotrovimab is being evaluated in the following clinical trials:
In March 2022, Australian virologists observed that sotrovimab may cause a drug-resistant mutation.
References
External links
Antiviral drugs
COVID-19 drug development
Drugs developed by GSK plc
Monoclonal antibodies
Withdrawn drugs | Sotrovimab | [
"Chemistry",
"Biology"
] | 1,471 | [
"Antiviral drugs",
"Drug discovery",
"Drug safety",
"COVID-19 drug development",
"Biocides",
"Withdrawn drugs"
] |
67,731,438 | https://en.wikipedia.org/wiki/Odevixibat | Odevixibat, sold under the brand name Bylvay among others, is a medication for the treatment of progressive familial intrahepatic cholestasis. It is taken by mouth. Odevixibat is a reversible, potent, selective inhibitor of the ileal bile acid transporter (IBAT). It was developed by Albireo Pharma.
The most common side effects include diarrhea, abdominal pain, hemorrhagic diarrhea, soft feces, and hepatomegaly (enlarged liver).
Odevixibat was approved for medical use in the United States and in the European Union in July 2021. The U.S. Food and Drug Administration considers it to be a first-in-class medication.
Medical uses
In the United States, odevixibat is indicated for the treatment of pruritus in people three months of age and older with progressive familial intrahepatic cholestasis. In the European Union it is indicated in people six months of age and older.
Mechanism of action
Odevixibat is a reversible inhibitor of the ileal sodium/bile acid co-transporter. This transporter is responsible for reabsorption of the majority of bile acids in the distal ileum. The reduced absorption of the bile acids in the distal ileum compounds and leads to a decrease in stimulation of FXR (farnesoid X receptor), decreasing the inhibition of bile acid synthesis.
Odevixibat works as a reversible, selective, small molecule inhibitor of the ileal bile acid transporter (IBAT).
Pharmacokinetics
Odevixibat is > 99% protein-bound in vitro. A dose of odevixibat that is 7.2 mg reaches a cmax concentration of 0.47 ng/mL with an AUC (0-24h) of 2.19 h*ng/mL. Adult and pediatric patients given the therapeautic dose of odevixibat did not display plasma concentrations of the drug. Odevixibat is eliminated majorly unchanged. Odevixibat has an average half-life of 2.36 hours.
The peak plasma time ranges from 1 to 5 hours after a single 7.2 mg dose in healthy adults. In healthy adults receiving a single 7.2 mg dose, the peak plasma concentration is 0.47 ng/mL, and the area under the concentration-time curve (AUC) is 2.19 ng·hr/mL. The plasma concentration of odevixibat in patients aged 6 months to 17 years ranges from 0.06 to 0.72 ng/mL. With once-daily dosing, there is no accumulation of odevixibat.
Odevixibat is metabolized through a process called mono-hydroxylation.The drug is primarily eliminated through the feces (97% unchanged), with a minimal amount excreted in the urine (0.002%).
Consuming a high-fat meal (800-1000 calories with approximately 50% of the total caloric content from fat) the peak plasma concentration is decreased by 72%, the AUC by 62%, and delays the peak plasma time by 3 to 4.5 hours. However, the impact of food on systemic exposures to odevixibat is not clinically significant.
Contraindications
Odevixibat cannot be given to a child on a liquid diet.
Adverse effects
Common side effects of odevixibat include diarrhea, stomach pain, vomiting, liver test abnormalities, abnormal liquid function tests, and a deficiency in vitamins A, D, E and K.
Pregnancy and lactation
There are no enough human data on odevixibat use during pregnancy to build a drug-associated risk of major birth defects, miscarriage, or adverse developmental outcomes.
There are no data on the presence of odevixibat in human milk, and how it affects milk production and breastfed babies.
History
Preclinical studies and early clinical trials were conducted to evaluate the safety and efficacy of odevixibat, to establish the appropriate dosage, assess its mechanism of action, and evaluate its effects on bile acid levels and symptoms in people with progressive familial intrahepatic cholestasis. A 24-week clinical trial, played a role in demonstrating the effectiveness and safety of odevixibat in treating pruritus in children with progressive familial intrahepatic cholestasis.
The US Food and Drug Administration (FDA) granted the application for odevixibat orphan drug designation. The FDA classified odevixibat as an orphan drug for the rare conditions of Alagille syndrome, biliary atresia, and primary biliary cholangitis.
Odevixibat was granted its initial approval in July 2021, in the European Union for the treatment of progressive familial intrahepatic cholestasis in people aged six months and older. In July 2021, it received approval in the United States for the treatment of pruritus (itching) in people aged three months and older with progressive familial intrahepatic cholestasis.
Society and culture
Legal status
In May 2021, the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) recommended granting a marketing authorization in the European Union for odevixibat for the treatment of progressive familial intrahepatic cholestasis in people aged six months or older. It was authorized for medical use in the European Union in July 2021.
In July 2024, the CHMP adopted a positive opinion, recommending the granting of a marketing authorization under exceptional circumstances for the medicinal product Kayfanda, intended for the treatment of cholestatic pruritus in people with Alagille syndrome aged six months or older. The applicant for this medicinal product is Ipsen Pharma. Kayfanda was authorized for medical use in the European Union in September 2024.
Research
A phase III randomized control trial showed odevixibat reduced pruritis and serum bile acids in children with progressive familial intrahepatic cholestasis.
References
External links
Orphan drugs
Thiadiazepines
4-Hydroxyphenyl compounds
Thioethers
Amides
Carboxylic acids
Tertiary amines | Odevixibat | [
"Chemistry"
] | 1,317 | [
"Carboxylic acids",
"Functional groups",
"Amides"
] |
67,731,939 | https://en.wikipedia.org/wiki/%C5%8Cya%20Tile%20Kiln | The is an archaeological site with the ruins of a Hakuho period kiln, located in the Ōya neighborhood of the city of Higashimatsuyama, Saitama Prefecture in the Kantō region of Japan. It was designated a National Historic Site of Japan in 1931.
Overview
roof tiles made of fired clay were introduced to Japan from Baekche during the 6th century along with Buddhism. During the 570s under the reign of Emperor Bidatsu, the king of Baekche sent six people to Japan skilled in various aspects of Buddhism, including a temple architect. Initially, tiled roofs were a sign of great wealth and prestige, and used for temple and government buildings. The material had the advantages of great strength and durability, and could also be made at locations around the country wherever clay was available.
The Ōya site is located on the southeastern slope of a hill in the northern part of the city of Higashmatsuyama. Discovered in 1955, two kilns were found during an excavation survey, lined up at a distance of about 50 meters. One was relatively well-preserved, and although it had lost its ceiling, the firing box was intact. The length of the kiln was about 7.6 meters, and was about 1.1 meters wide at the center. The kilns a noborigama-type kiln in 13 steps, with flat tiles fixed to the upper edges and walls of each step. This type of flat tile is also used at the top of the south wall of the kiln and at the entrance to the firing box. Unearthed relics include eaves tiles, flat tiles, round tiles, and letter tiles, which were dated to the Hakuho period.
See also
List of Historic Sites of Japan (Saitama)
References
External links
Higashimatsuyama City official home page
Higashimatsuyama, Saitama
Historic Sites of Japan
History of Saitama Prefecture
Musashi Province
Nara period
Japanese pottery kiln sites | Ōya Tile Kiln | [
"Chemistry",
"Engineering"
] | 401 | [
"Kilns",
"Japanese pottery kiln sites"
] |
67,731,944 | https://en.wikipedia.org/wiki/Gennady%20Makanin | Gennady (or Gennadii or Gennadiy) Semenovich Makanin (1938–2017) was a Russian mathematician, awarded the 2010 I. M. Vinogradov Prize for a series of papers on the problem of algorithmically recognizing the solvability of arbitrary equations in free groups and semigroups.
Education and career
At Moscow State University he received his undergraduate degree and in 1967 his Russian Candidate of Sciences degree (PhD). His dissertation К проблеме тождества в конечно-определённых группах и полугруппах (On the identity problem in finitely-presented groups and semigroups) was supervised by Andrey Markov Jr. and Sergei Adian.
Makanin spent his career (since 1966) working at the Steklov Institute of Mathematics (since 2013 as a freelance employee). From the Steklov Institute of Mathematics he received in 1977 his Russian Doctor of Sciences degree (similar to habilitation) with dissertation Проблема разрешимости уравнений в свободной полугруппе (The problem of solvability of equations in a free semigroup). On the basis of his 1977 dissertation he was an invited speaker at the 1978 International Congress of Mathematicians in Helsinki.
He gained international recognition for his research on combinatorial group theory and algorithmic problems in the theory of semigroups. Zlil Sela, Eliyahu Rips, and others have made important applications of Makanin-Razborov diagrams to geometric group theory.
In 1982 Makanin published a complete solution (an algorithm with proof of validity) to the problem of recognizing the solvability of equations in a free group. An English translation was published in 1983. In 1984 (followed by English translation in 1985) he published a proof, using techniques similar to those in his 1982 paper, of the decidability, for any free group, of two different formal theories generated by that free group.
Remarks on Makanin's research
Martin Davis and Julia Robinson worked unsuccessfully on the problem which was eventually solved in 1977 by Makanin:
Yuri Matiyasevich published a generalization of what he called the "celebrated theorem of G. S. Makanin about decidability of word equations".
Selected publications
References
External links
Маканин Геннадий Семёнович (Russian full list of publications)
Makanin, Gennadiy Semenovich (English full list of publications)
http://www.mathnet.ru/person/13873
1938 births
2017 deaths
Mathematical logicians
Soviet logicians
Russian logicians
20th-century Russian philosophers
21st-century Russian philosophers
Soviet mathematicians
20th-century Russian mathematicians
21st-century Russian mathematicians
Moscow State University alumni | Gennady Makanin | [
"Mathematics"
] | 636 | [
"Mathematical logic",
"Mathematical logicians"
] |
67,731,989 | https://en.wikipedia.org/wiki/Taraxacin | Taraxacin is a guaianolide with the molecular formula C15H14O3 which has been isolated from the plant Taraxacum officinale. Taraxacin has a bitter taste. Taraxacin has diuretic properties.
References
Further reading
Furanones
Heterocyclic compounds with 3 rings
Cyclopentenes
Ketones | Taraxacin | [
"Chemistry"
] | 75 | [
"Ketones",
"Functional groups",
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
67,732,953 | https://en.wikipedia.org/wiki/Post-Minkowskian%20expansion | In physics, precisely in the general theory of relativity, post-Minkowskian expansions (PM) or post-Minkowskian approximations are mathematical methods used to find approximate solutions of Einstein's equations by means of a power series development of the metric tensor.
Unlike post-Newtonian expansions (PN), in which the series development is based on a combination of powers of the velocity (which must be negligible compared to that of light) and the gravitational constant, in the post-Minkowskian case the developments are based only on the gravitational constant, allowing analysis even at velocities close to that of light (relativistic).
One of the earliest works on this method of resolution is that of Bruno Bertotti, published in Nuovo Cimento in 1956.
References
General relativity | Post-Minkowskian expansion | [
"Physics"
] | 168 | [
"General relativity",
"Theory of relativity"
] |
67,733,773 | https://en.wikipedia.org/wiki/Dyhia%20Belhabib | Dyhia Belhabib is an environmental scientist and researcher specialising in illegal fishing, conservation, artisanal fishing and food security. She is currently principal fisheries investigator for Ecotrust Canada and founder of Spyglass. Her research has investigated the link between fishing industry and the illegal drug trade and conflict between artisanal fishing, illegal fishing, climate change and international fishing subsidies. She has also advocated for decolonization and greater equity in ocean science.
References
External links
Living people
Environmental scientists
Fisheries scientists
University of British Columbia Faculty of Science alumni
Year of birth missing (living people)
Postcolonial theorists
Conservationists
Women environmentalists | Dyhia Belhabib | [
"Environmental_science"
] | 127 | [
"Canadian environmental scientists",
"Environmental scientists"
] |
54,974,922 | https://en.wikipedia.org/wiki/Dimethyloctadecyl%283-trimethoxysilylpropyl%29ammonium%20chloride | Dimethyloctadecyl(3-trimethoxysilylpropyl)ammonium chloride (DTSACl) is a disinfectant used as a preservative and fungicide. Its chemical formula is C26H58NO3SiCl. It is also used as a silane coupling agent.
See also
Dimethyldioctadecylammonium chloride
References
Disinfectants
Methoxy compounds
Siloxanes
Quaternary ammonium compounds
Chlorides | Dimethyloctadecyl(3-trimethoxysilylpropyl)ammonium chloride | [
"Chemistry"
] | 103 | [
"Chlorides",
"Inorganic compounds",
"Salts"
] |
54,975,315 | https://en.wikipedia.org/wiki/Embudo%20Stream%20Gauging%20Station | The Embudo Stream Gauging Station is a stream gauge established in 1888 as the United States Geologic Survey's first training center for hydrographers. The station, near the town of Embudo along the Rio Grande in northern New Mexico, was used to develop tools and techniques for measuring stream flow in the arid, western United States.
History
The Embudo Stream Gauging Station was established as part of the United States Geologic Survey Irrigation Survey, a project to map water basins and collect streamflow data in an effort to make informed irrigation infrastructure decisions, directed by Clarence Dutton. While Dutton was able to locate topographers and irrigation engineers for the survey, he was not able to locate hydrographers, so a training camp was established at Embudo, New Mexico. Engineers, including camp director Frederick H.Newell, first arrived in December 1888. While canvas tents and cots were purchased, the unanticipated cold of the higher elevation site led to the use of shallow trenches with blankets rather than cots and small cave dug in a nearby hillside for sleeping.
By early March 1889, the camp hosted 21 residents, including 15 students. The training period ended in April 1889 with ten of the students taking on hydrographer positions in the Irrigation Survey. Stream measurements were continued by the local railroad agent until 1904 and were then discontinued. Measurements resumed in 1912 by a new railroad agent, and in 1915 the station operation was taken on by the State of New Mexico. The USGS resumed operation of the stream gauging station in July 1931.
Recognition
The site was designated a Historic Civil Engineering Landmark by the American Society of Civil Engineers in 1973 and listed on the New Mexico State Register of Cultural Properties in 1974.
See also
Willow Beach Gauging Station
References
New Mexico State Register of Cultural Properties
Historic Civil Engineering Landmarks | Embudo Stream Gauging Station | [
"Engineering"
] | 370 | [
"Civil engineering",
"Historic Civil Engineering Landmarks"
] |
54,975,484 | https://en.wikipedia.org/wiki/Vicente%20Sota | Vicente Agustín Sota Barros (24 April 1924 – 16 August 2017) was a Chilean politician. He served two stints in the Chamber of Deputies, first from 1965 to 1969 and again from 1990 to 1998.
Career
Born in Talca on 28 April 1924, he earned a degree in industrial engineering from Pontifical Catholic University of Chile. Sota joined the National Falange in 1940, and upon the party's dissolution in 1957, became a member of the Christian Democratic Party. While affiliated with the PDC, Sota served in the Chamber of Deputies as a representative of central Santiago between 1965 and 1969. Shortly after the end of his first term in office, Sota cofounded the Popular Unitary Action Movement.
Sota left Chile for France after the 1973 Chilean coup d'état, where he spent thirteen years until returning to Chile in March 1986. The next year, Sota co-founded the Party for Democracy.
He won two more parliamentary elections after joining the PPD, in 1989 and 1993, representing district 31, which covered portions of Santiago from 1990 to 1998. Between November 1994 and March 1995, Sota served as President of the Chamber of Deputies of Chile.
References
External links
BCN Profile
1924 births
2017 deaths
Presidents of the Chamber of Deputies of Chile
Christian Democratic Party (Chile) politicians
Popular Unitary Action Movement politicians
Party for Democracy (Chile) politicians
20th-century Chilean engineers
Industrial engineers
People from Talca
Pontifical Catholic University of Chile alumni
Chilean exiles
Chilean expatriates in France
21st-century Chilean engineers
Deputies of the XLV Legislative Period of the National Congress of Chile
Deputies of the XLVIII Legislative Period of the National Congress of Chile
Deputies of the XLIX Legislative Period of the National Congress of Chile | Vicente Sota | [
"Engineering"
] | 347 | [
"Industrial engineers",
"Industrial engineering"
] |
54,976,053 | https://en.wikipedia.org/wiki/LArIAT | LArIAT (Liquid Argon In A Testbeam) is a neutrino experiment located at the Fermi National Accelerator Laboratory (Fermilab), Chicago. It is capable of both accurately identifying and making precise 3D spatial and calorimetric measurements of particles. Currently, it is in the calibration phase of development. At present, the LArIAT collaboration has more than 65 members from 17 institutions worldwide, including Yale University, the University of Manchester, and KEK.
The LArIAT detector
LArIAT itself is a cylindrical cryostat with convex ends, capable of holding 550L of liquid argon. The cryostat is heavily insulated thermally, in part by a region of vacuum surrounding it. Inside the cryostat is the time projection chamber, in which the argon atoms are ionized by beam particles. An electric field is applied across the chamber perpendicular to the beam direction, causing the ionization electrons to move towards the side, where they are detected by two wire planes oriented at ±30° to the vertical. These wire planes are made up of 240 parallel wires with a separation of 4mm. A third wire plane of 225 wires, aligned along the vertical axis, is placed in front of the other two planes in order to prevent the electric field from interfering with the instrumentation.
Ionization of liquid argon emits characteristic 128 nm light (in the violet/ultraviolet range), which is detected by a scintillation read-out system. This system has a high efficiency, having been designed using systems developed for dark matter liquid argon detectors. This gives LArIAT an advantage over other existing liquid argon detectors which are only able to perform calorimetry using the wire grids.
References
Neutrino experiments
Dark matter | LArIAT | [
"Physics",
"Astronomy"
] | 360 | [
"Dark matter",
"Unsolved problems in astronomy",
"Concepts in astronomy",
"Unsolved problems in physics",
"Exotic matter",
"Physics beyond the Standard Model",
"Matter"
] |
54,976,874 | https://en.wikipedia.org/wiki/Infectious%20tolerance | Infectious tolerance is a term referring to a phenomenon where a tolerance-inducing state is transferred from one cell population to another. It can be induced in many ways; although it is often artificially induced, it is a natural in vivo process. A number of research deal with the development of a strategy utilizing this phenomenon in transplantation immunology. The goal is to achieve long-term tolerance of the transplant through short-term therapy.
History
The term "infectious tolerance" was originally used by Gershon and Kondo in 1970 for suppression of naive lymphocyte populations by cells with regulatory function and for the ability to transfer a state of unresponsiveness from one animal to another. Gershon and Kondo discovered that T cells can not only amplify but also diminish immune responses. The T cell population causing this down-regulation was called suppressor T cells and was intensively studied for the following years (nowadays they are called regulatory T cells and are again a very attractive for research). These and other research in the 1970s showed greater complexity of immune regulation, unfortunately these experiments were largely disregarded, as methodological difficulties prevented clear evidence. Later developed new tolerogenic strategies have provided strong evidence to re-evaluate the phenomenon of T cell mediated suppression, in particular the use of non-depleting anti-CD4 monoclonal antibodies, demonstrating that neither thymus nor clonal deletion is necessary to induce tolerance. In 1989 was successfully induced classical transplantation tolerance to skin grafts in adult mice using antibodies blocking T cell coreceptors in CD4+ populations. Later was shown that the effect of monoclonal antibodies is formation of regulatory T lymphocytes. It has been shown that transfer of tolerance to other recipients can be made without further manipulation and that this tolerance transfer depends only on CD4+ T-lymphocytes. Because second-generation tolerance arises in the absence of any monoclonal antibodies to CD4 or CD8, it probably represents a natural response of the immune system, which, once initiated, becomes self-sustaining. This ensures the long duration of once induced tolerance, for as long as the donor antigens are present.
Mechanisms
During a tolerant state potential effector cells remain but are tightly regulated by induced antigen-specific CD4+ regulatory T cells (iTregs). Many subsets of iTregs play a part in this process, but CD4+CD25+FoxP3+ Tregs play a key role, because they have the ability to convert conventional T cells into iTregs directly by secretion of the suppressive cytokines TGF-β, IL-10 or IL-35, or indirectly via dendritic cells (DCs). Production of IL-10 induces the formation of another population of regulatory T cells called Tr1. Tr1 cells are dependent on IL-10 and TGF-β as well as Tregs, but differ from them by lacking expression of Foxp3. High IL-10 production is characteristic for Tr1 cells themselves and they also produce TGF-β. In the presence of IL-10 can be also induced tolerogenic DCs from monocytes, whose production of IL-10 is also important for Tr1 formation. These interactions lead to the production of enzymes such as IDO (indolamine 2,3-dioxygenase) that catabolize essential amino acids. This microenvironment with a lack of essential amino acids together with other signals results in mTOR (mammalian target of rapamycin) inhibition which, particularly in synergy with TGF-β, direct the induction of new FoxP3 (forkhead box protein 3) expressing Tregs.
See also
Immune tolerance
Central tolerance
Peripheral tolerance
regulatory T cells
Immune response
Immune tolerance in pregnancy
References
Biology
Immunology | Infectious tolerance | [
"Biology"
] | 786 | [
"Immunology"
] |
54,978,246 | https://en.wikipedia.org/wiki/Fergus%20W.%20Campbell | Fergus William Campbell (30 January 1924 – 3 May 1993) was a Scottish
vision scientist who conducted foundational research into the optics of the human eye, into the electrical activity of the brains of people experiencing various phenomena of vision, and into the sorts of images which, when shown to people, might reveal the processes of their visual systems. Campbell's research changed the course of vision science.
Life and education
Campbell was born on 30 January 1924 in Glasgow, Scotland. His father, William Campbell (1891–1968), was a pharmacist and doctor; his mother, Anne Fleming (1898–1984) was her future husband's counter assistant before taking care of their four children. Campbell was his parents' second child and their first boy. His parents provided an intellectually nurturing home full of books. Campbell received his primary and secondary education at Glasgow High School for Boys. As a child, Campbell was an avid reader and, encouraged by his teachers and father, had hobbies in chemistry, physics, optics, photography, electricity, and radio.
Campbell studied medicine at Glasgow University Medical School, graduating in 1946. After graduating, Campbell prepared to become an ophthalmologist, passing the Diploma of Ophthalmic Medicine and Surgery from the Royal College of Surgeons in 1948. But Campbell became more interested in research than in clinical practice, completing a PhD (on corneal wound healing) from Glasgow University in 1952, then an MD (on the depth of focus of the eye) in 1959.
Although Campbell's research work took him to Oxford University and then University of Cambridge, both in England, he remained true to his Scottish heritage and his humble origins. He was much beloved by colleagues and students, renowned for his kindliness, generosity, and stock of good stories.
While doing his medical studies at University of Glasgow, Campbell met his wife-to-be, Helen, who became a doctor. They married in 1947 and had four children, one of whom died at 17 in a riding accident. Campbell was afflicted lifelong by ankylosing spondylitis, and by bouts of iritis. He died on 3 May 1993.
Career
While studying for his PhD and MD, Campbell worked as an ophthalmologist from around 1948 to 1951. He then spent a year at Nuffield Laboratory in Oxford working with T.C.D. Whiteside on aviation medicine.
In 1953, Campbell was appointed as a lecturer at the Cambridge Physiological Laboratory. He spent the remainder of his career there, eventually winning a personal chair in Neurosensory Physiology before retiring in 1991. He was a Fellow at St. John's College.
According to Neurotree, Campbell supervised one research assistant, four PhD students (David C. Burr, Denis Pelli, John G. Robson, and Roger Carpenter), and seven post-doctoral fellows (including Colin Blakemore, Robert Shapley, and Gordon Legge). These academic children produced 120 academic grandchildren.
He collaborated with T. C. D. Whiteside and William Rushton.
Community service
Between 1960 and 1962, Campbell served on the General Optical Council of the
UK National Health Service, representing educational interests for optometry.
Campbell was an Advisory Editor of Spatial Vision, and a member of the editorial board of Ophthalmic and Physiological Optics.
Research
Selected works
Honours
In 1959, Campbell became the 14th Foundation lecturer of the British Optical Association. In 1962, he was awarded an honorary Fellowship of The British Optical Association. In 1878, Campbell was elected as a Fellow of the Royal Society. He won the Tillyer Medal from the Optical Society of America in 1980, and was awarded an honorary Doctor of Science from University of Glasgow in 1986 and from Aston University in 1987.
References
1924 births
1993 deaths
Scottish scientists
Fellows of the Royal Society
Fellows of St John's College, Cambridge
Alumni of the University of Glasgow
Scientists from Glasgow
Psychophysics
Vision scientists | Fergus W. Campbell | [
"Physics"
] | 795 | [
"Psychophysics",
"Applied and interdisciplinary physics"
] |
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