id int64 39 79M | url stringlengths 31 227 | text stringlengths 6 334k | source stringlengths 1 150 ⌀ | categories listlengths 1 6 | token_count int64 3 71.8k | subcategories listlengths 0 30 |
|---|---|---|---|---|---|---|
70,519,561 | https://en.wikipedia.org/wiki/Transition%20metal%20complexes%20of%202%2C2%27-bipyridine | Transition metal complexes of 2,2'-bipyridine are coordination complexes containing one or more 2,2'-bipyridine ligands. Complexes have been described for all of the transition metals. Although few have any practical value, these complexes have been influential. 2,2'-Bipyridine (bipy) is classified as a diimine ligand. Unlike the structures of pyridine complexes, the two rings in bipy are coplanar, which facilitates electron delocalization. As a consequence of this delocalization, bipy complexes often exhibit distinctive optical and redox properties.
Complexes
Bipy forms a wide variety of complexes. Almost always, it is a bidentate ligand, binding metal centers with the two nitrogen atoms. Examples:
Mo(CO)4(bipy), derived from Mo(CO)6.
RuCl2(bipy)2, a popular precursor to mixed ligand complexes.
[Ru(bipy)3]2+, a well studied luminophore.
[Fe(bipy)3]2+ has been used for the colorimetric analysis of iron ions.
{[Ru(bipyridine)2(OH2)]2(O)}2+, "ruthenium blue" has attracted academic interest as a rare complex that catalyzes the oxidation of water.
Tris-bipy complexes
Bipyridine complexes absorb intensely in the visible part of the spectrum. The electronic transitions are attributed to metal-to-ligand charge transfer (MLCT). In the "tris(bipy) complexes" three bipyridine molecules coordinate to a metal ion, written as [M(bipy)3]n+ (M = metal ion; Cr, Fe, Co, Ru, Rh and so on). These complexes have six-coordinated, octahedral structures and exists as enantiomeric pairs:
These and other homoleptic tris-2,2′-bipy complexes of many transition metals are electroactive. Often, both the metal centred and ligand centred electrochemical reactions are reversible one-electron reactions that can be observed by cyclic voltammetry. Under strongly reducing conditions, some tris(bipy) complexes can be reduced to neutral derivatives containing bipy− ligands. Examples include M(bipy)3, where M = Al, Cr, Si.
Square planar complexes
Square planar complexes of the type [Pt(bipy)2]2+ react with nucleophiles because of the steric clash between the 6,6' positions between the pair of bipy ligands. This clash is indicated by the bowing of the pyridyl rings out of the plane defined by PtN4.
Related ligands
Many ring-substituted variants of bipy have been described, especially dimethyl-2,2'-bipyridines. Alkyl substituents enhance the solubility of the complexes in organic solvents. 6,6'-Substituents tend to protect the metal center.
The related N,N-heterocyclic ligand phenanthroline forms similar complexes. With respective pKa's of 4.86 and 4.3 for their conjugate acids, phenanthroline and bipy are of comparable basicity.
2,2'-Biquinoline is closely related to bipy as a ligand.
References
Chelating agents
Bipyridine complexes | Transition metal complexes of 2,2'-bipyridine | [
"Chemistry"
] | 725 | [
"Chelating agents",
"Process chemicals"
] |
70,519,860 | https://en.wikipedia.org/wiki/Nitride%20iodide | An iodide nitride is a mixed anion compound containing both iodide (I−) and nitride ions (N3−). Another name is metalloiodonitrides. They are a subclass of halide nitrides or pnictide halides. Some different kinds include ionic alkali or alkaline earth salts, small clusters where metal atoms surround a nitrogen atom, layered group 4 element 2-dimensional structures (which could be exfoliated to a monolayer), and transition metal nitrido complexes counter-balanced with iodide ions. There is also a family with rare earth elements and nitrogen and sulfur in a cluster.
Related mixed-anion compounds include halogen variations: nitride fluoride, nitride chloride, and nitride bromide, and pnictogen variations phosphide iodide, arsenide iodide and antimonide iodides.
Production
Nitride iodides may be produced by heating metal nitrides with metal iodides. The ammonolysis process heats a metal iodide with ammonia. A related method heats a metal or metal hydride with ammonium iodide. The nitrogen source could also be an azide or an amide.
List
References
Iodides
Mixed anion compounds
Nitrides | Nitride iodide | [
"Physics",
"Chemistry"
] | 282 | [
"Ions",
"Matter",
"Mixed anion compounds"
] |
74,761,761 | https://en.wikipedia.org/wiki/Thermoascus%20aegyptiacus | Thermoascus aegyptiacus is a species of fungus in the genus Thermoascus in the order of Eurotiales.
Taxonomy
Before adaptation of the "one fungus - one name" rule, Paecilomyces aegyptiacus referred to the anamorph, while T. aegyptiacus and briefly Coonemeria aegyptiaca referred to the teleomorph.
References
Thermoascaceae
Fungi described in 1983
Fungus species | Thermoascus aegyptiacus | [
"Biology"
] | 105 | [
"Fungi",
"Fungus species"
] |
74,761,769 | https://en.wikipedia.org/wiki/Thermoascus%20aurantiacus | Thermoascus aurantiacus is a species of fungus in the genus Thermoascus in the order of Eurotiales.
References
Thermoascaceae
Fungi described in 1907
Fungus species | Thermoascus aurantiacus | [
"Biology"
] | 44 | [
"Fungi",
"Fungus species"
] |
74,761,795 | https://en.wikipedia.org/wiki/Thermoascus%20crustaceus | Thermoascus crustaceus is a species of fungus in the genus Thermoascus in the order of Eurotiales.
References
Thermoascaceae
Fungi described in 1965
Fungus species | Thermoascus crustaceus | [
"Biology"
] | 43 | [
"Fungi",
"Fungus species"
] |
74,762,129 | https://en.wikipedia.org/wiki/Thermoascus%20isatschenkoi | Thermoascus isatschenkoi is a species of fungus in the genus Thermoascus in the order of Eurotiales.
References
Thermoascaceae
Fungi described in 1939
Fungus species | Thermoascus isatschenkoi | [
"Biology"
] | 44 | [
"Fungi",
"Fungus species"
] |
74,762,283 | https://en.wikipedia.org/wiki/Thermoascus%20taitungiacus | Thermoascus taitungiacus is a species of fungus in the genus Thermoascus in the order of Eurotiales.
References
Thermoascaceae
Fungi described in 1996
Fungus species | Thermoascus taitungiacus | [
"Biology"
] | 44 | [
"Fungi",
"Fungus species"
] |
74,762,326 | https://en.wikipedia.org/wiki/Thermoascus%20thermophilus | Thermoascus thermophilus is a species of fungus in the genus Thermoascus in the order of Eurotiales.
References
Thermoascaceae
Fungi described in 1912
Fungus species | Thermoascus thermophilus | [
"Biology"
] | 45 | [
"Fungi",
"Fungus species"
] |
74,762,357 | https://en.wikipedia.org/wiki/Thermoascus%20yaguchii | Thermoascus yaguchii is a species of fungus in the genus Thermoascus in the order of Eurotiales.
References
Thermoascaceae
Fungi described in 1995
Fungus species | Thermoascus yaguchii | [
"Biology"
] | 43 | [
"Fungi",
"Fungus species"
] |
74,763,035 | https://en.wikipedia.org/wiki/ARTC%20HD63484 | Hitachi LSI HD63484 Advanced CRT Controller chip (ACRTC) is a GPU created by Hitachi in 1984 that supports 4K display resolution.
Description
The LSI HD63484 was built in 2 μm CMOS technology and had about 60,000 MOSFETs and could operate at 8 MHz. ARTC introduced a screen resolution of 4096×4096 pixels at 1-bit color depth (monochrome), or 1024×1024 at 16-bit color (65,536 colors). Focused on computer graphics for the emerging desktop publishing market with bitmap printing. The chip had the ability to program the synchronization signal of CRT monitors. It could support up to 2 megabytes of video memory and offered an asynchronous DMA bus interface that could be mapped to 16-bit ISA and VME buses.
See also
NEC μPD7220
TMS34010
List of Intel GPUs
Literature
Baraa Al-Hilali. Mathematical Representation of Color Spaces and Its Role in Communication Systems. Journal of Applied Mathematics. Hindawi, 2020.
Amit Joshi, Nilanjan Dey, Simon Sherratt, Xin-She Yang. Proceedings of Sixth International Congress on Information and Communication Technology. ICICT 2021, London, Volume 2. Springer Nature Singapore, 2021. .
Gustavo Henrique Cervi. Pipeline Metagenômico Com o Uso de Algoritmo de Compressão Lossy e Matching Heurístico Não-Determinístico. Porto Alegre, 2022.
Jon Peddie. The History of the GPU - Steps to Invention. Springer Nature, 2023. .
Notes
External links
日立評論1984年7月号:グラフィック ディスプレイ コントローラACRTC“HD63484” - 1984_07_10.pdf
Hitachi HD63484 ACRTC
Resolusi 4K
Hitachi Semiconductor
GPU History: Hitachi ARTC HD63484. The second graphics processor
Graphics processing units
Hitachi products | ARTC HD63484 | [
"Technology"
] | 451 | [
"Computing stubs",
"Computer hardware stubs"
] |
74,763,793 | https://en.wikipedia.org/wiki/Monepantel | Monepantel is an anthelmintic approved for use in sheep and cattle to control gastrointestinal nematodes. It belongs to a new class of anthelmintics called aminoacetonitrile derivatives (AAD). It is marketed by Elanco as Zolvix (United Kingdom) as a single active, or Zolvix Plus (New Zealand, Australia) in combination with the macrocyclic lactone abamectin.
History
Aminoacetonitrile derivatives were originally discovered by scientists working at Novartis to have high potency against in vitro parasite models. Compounds were further validated in rodent parasite models following oral and subcutaneous administration. A lead compound AAD 1566 was isolated that eliminated pathogenic nematodes at doses of 2.5 mg/kg in sheep and 5.0 mg/kg in cattle and was named monepantel. The structure and anthelmintic activity of monepantel were first described in patent WO2005/44784.
It was first registered in 2009 for use in sheep in New Zealand to control adult and immature L4 stages of all major GI nematodes.
Mechanism of action
Studies using a molecular genetic approach in C. elegans indicated that AADs worked via ligand-gated ion channels. Further research identified the DEG-3 subfamily of nicotinic acetylcholine receptors as the likely putative target of monepantel. Rufener et al published in 2009 that MPTL-1 was the likely binding site of monepantel in Haemonchus contortus. The DEG-3 subfamily is absent in mammals and this might explain the minimal toxicity of monepantel. It has been shown the AADs and monepantel in particular potentiate DEG-3/Des-2 receptors of H. contortus acting as an agonist of the nicotinic acetylcholine receptor producing spastic paralysis and death of the nematode. Interestingly, only the S-enantiomer is found to be active against gastrointestinal nematodes.
Pharmacology
After administration to either sheep or cattle, monepantel is rapidly converted to its major metabolite monepantel sulphone, which also has similar levels of efficacy against gastrointestinal nematodes compared to the parent compound.
Sheep
Data on the pharmacokinetics of monepantel in sheep following intravenous and oral dosing have been published. The sulphone metabolite was rapidly formed and predominated after four hours regardless of the route of administration. Following oral dosing of sheep with 3 mg/kg of monepantel the Tmax, Cmax and AUC of monepantel were 16 h, 17.9 ng/mL and 671 ng.h/mL, while for the sulphone metabolite they were 24 h, 94.3 ng/mL and 11125 ng.h/mL.
Cattle
After oral treatment of dairy cattle monepantel and monepantel sulphone are found in the plasma and milk. Monepantel is rapidly converted to the major metabolite monepantel sulphone which is then found in much higher concentration and lasts much longer in tissues than the parent compound. In one study in calves dosed orally with 2.5 mg/kg of monepantel the Tmax was 8 hours, Cmax 21.5 ng/mL and AUC 2174 ng.h/mL, while the major metabolite monepantel sulphone had a Tmax of 41.3 hours, Cmax of 96.8 ng/mL and AUC of 10242 ng.h.mL. In dairy cows given monepantel orally the major metabolite observed in plasma and milk was monepantel sulphone. Monepantel was detected for up to 33 hours in milk and the sulphone metabolite up to 177 hours. The milk concentrations of the sulphone metabolite were substantially higher than the plasma with the AUC being nearly 7 fold higher in milk than plasma. There was no significant change in the pharmacokinetics with the addition of oxfendazole.
Efficacy
As an oral drench dosed at 2.5 mg/kg in sheep it has claimed efficacy against adult and immature L4 stages of all major GI nematodes, namely: Haemonchus contortus, Teladorsagia circumcincta, Teladorsagia trifurcata, Trichostrongylus axei, Trichostrongylus colubriformis, Trichostrongylus rugatus, Trichostrongylus vitrinus, Nematodirus, battus, Nematodirus filicollis, Nematodirus spathiger (adult stage only), Nematodirus abnormalis (only adult stage tested), Cooperia curticei, Cooperia oncophora, Oesophagostomum venulosum (L4 stageonly) Chabertia ovina
Safety
In sheep monepantel is considered to have a good safety profile. Weaned lambs treated with 1x, 3x and 5x doses every 21 days for 8 occasions were found to be unaffected with no adverse events noted. Between control lambs and treated lambs there were no significant differences in body weight, organ weight, blood chemistry and haematology and coagulation detected.
Anthelmintic resistance
Due to having a different mode of action and molecular target than other anthelmintics, monepantel will generally kill nematodes resistant to the other major classes of anthelmintics. However, within a few years of monepantel's release on the market, anthelmintic resistance was reported in several countries including Australia, New Zealand, Uruguay, Brazil, the Netherlands and the United Kingdom. These reports have shown a number of species were resistant to monepantel, including Haemonchus contortus, Teladorsagia circumcincta, Trichostrongylus colubriformis, and Oesophagostomum.
References
Anthelmintics
Trifluoromethylthio compounds
Trifluoromethyl compounds
Nitriles
Carboxamides | Monepantel | [
"Chemistry"
] | 1,320 | [
"Nitriles",
"Functional groups"
] |
74,764,421 | https://en.wikipedia.org/wiki/Tremella%20iduensis | Tremella iduensis is a species of fungus in the family Tremellaceae. It produces yellow, cornute-frondose, gelatinous basidiocarps (fruit bodies) and is parasitic on other fungi, probably species of Hypoxylon on dead attached and recently fallen branches of broad-leaved trees. It has been recorded from Japan and China. Tremella flava, described from Taiwan, may be a synonym.
Taxonomy
Tremella iduensis was first published in 1939 by Japanese mycologist Yosio Kobayasi.
Description
Fruit bodies are gelatinous, bright yellow, up to 2.5 cm (1 in) across, and branched, with cornute (horn-like) fronds. Microscopically, the basidia are tremelloid (ellipsoid, with oblique to vertical septa), 4-celled, 17 to 18 by 12 to 13 μm. The basidiospores are ovoid to ellipsoid, smooth, 8.5 to 9.5 by 7.5 to 8.5 μm.
Similar species
Tremella flava was described from Taiwan as "resembling T. iduensis" but differing in the size of its basidiospores (7 to 9 by 5 to 6.5 μm) and basidia. It has been suggested it may be a later synonym of T. iduensis. Other yellow Tremella species are lobed or foliaceous and lack horn-like fronds.
Habitat and distribution
Tremella iduensis is a parasite on lignicolous fungi, probably species of Hypoxylon. It was originally described from Castanopsis sieboldii and is found on dead, attached or recently fallen branches of broad-leaved trees.
The species is currently known from Japan and China.
References
iduensis
Fungi described in 1939
Fungi of Asia
Fungus species | Tremella iduensis | [
"Biology"
] | 402 | [
"Fungi",
"Fungus species"
] |
74,765,346 | https://en.wikipedia.org/wiki/Alan%20Coulson | Alan Coulson (born 1947) is a British biotechnology pioneer and genome scientist. He is best known for his work on developing DNA sequencing technologies with Frederick Sanger and his contributions to the Caenorhabditis elegans and human genome projects.
Biography
Alan Coulson was born in Cambridge in 1947 and as a youth attended the Cambridge Grammar School for Boys and subsequently the Deacon's School in Peterborough. He achieved his higher national diploma in Applied Biology from Leicester Polytechnic in 1967.
Under the mentorship of John Sulston, Coulson completed his PhD titled The Physical Map of the C. elegans Genome, in 1994.
Career
Coulson joined Sanger's group at the Medical Research Council’s Laboratory of Molecular Biology (LMB) as a technician in 1967, shortly after receiving his diploma. With Sanger, Coulson developed many of the early DNA sequencing technologies, including the DNA polymerase primed synthesis ("plus and minus") technique and, eventually, dideoxynucleotide chain-terminating sequencing, which was later termed Sanger sequencing.
Sanger readily acknowledged Coulson's contributions to the development of DNA sequencing technologies, describing him as "my main collaborator in the later DNA work".
After Sanger's retirement in 1983, Coulson contributed to the physical mapping and genome sequencing project of the nematode C. elegans, led by John Sulston and Bob Waterston at the LMB and subsequently the Sanger Centre. This effort was the first to produce the complete genome sequence of an animal. Coulson later contributed to the human genome project.
Coulson left the Sanger Center (by then renamed the Wellcome Trust Sanger Institute) in 2003 and returned to work at the LMB until his retirement in 2007.
References
Living people
1947 births
English geneticists
Scientists from Cambridge
Alumni of Leicester Polytechnic
Human Genome Project scientists
Medical Research Council (United Kingdom) people | Alan Coulson | [
"Engineering"
] | 398 | [
"Human Genome Project scientists"
] |
74,766,274 | https://en.wikipedia.org/wiki/Paecilomyces%20formosus | Paecilomyces formosus is a species of fungus in the genus Paecilomyces in the order of Eurotiales.
History
The genus Paecilomyces formosus was first introduced in 2009 as species name for the anamorph form of Monilia formosa, ranked in Monilinia, originally described in 1939. Due to an invalid original description of M. formosa, the name P. formosus was also considered invalid. In the process of reclassification of fungi following adaptation of the "One fungus, one name" principle, it was suggested to be a synonym of P. maximus. In 2023, whole genome sequencing allowed a proper description of P. formosus, clearly distinct to P. maximus and P. lecythidis.
References
formosus
Fungi described in 1939
Fungus species | Paecilomyces formosus | [
"Biology"
] | 174 | [
"Fungi",
"Fungus species"
] |
74,766,728 | https://en.wikipedia.org/wiki/Robert%20Va%C3%9Fen | Robert Vaßen is a German physicist and holds a teaching professorship at the Ruhr University Bochum at the Institute of Materials in the Department of Ceramics Technology. He is head of the department "Materials for High Temperature Technologies" and deputy head of the Institute of Energy Materials and Devices (IMD-2): Materials Synthesis and Processing at Forschungszentrum Jülich.
Life and career
Vaßen studied physics at the RWTH Aachen University from 1980 to 1986, where he received his diploma. At the same university, he received his PhD in solid-state physics under Prof. Uhlmaier with the thesis Diffusion of Helium in Cubic-Space-Centered and Hexagonal Metals in 1990. After his PhD, he was a scientific assistant at IEK-1 Institute for Energy and Climate Research (now Institute of Energy Materials and Devices IMD-2), Forschungszentrum Jülich, where he became head of department in 1998 and deputy head of the institute since 2014. During this time, he habilitated at Ruhr University Bochum in 2004 with the topic of development of new oxide thermal barrier coatings for applications in stationary and aero-gas turbines. Since 2010, he has been a visiting professor at the University West, Trollhättan, Sweden. In 2014, he turned down a call for a W3 professorship in coating technology at the Technische Universität Berlin.
Since 2014, Vaßen has been a PhD supervisor of more than 75 students, 40 of them his own PhD students at the Ruhr University Bochum and the others as co-lecturer at various universities such as University West, Trollhättan, Sweden, University of Cambridge, Imperial College London and University of Manchester, all three United Kingdom, University of Stuttgart, University of Bayreuth, Mines Paris Tech, and others.
Research focus
Vaßen's research focuses on the development of high-temperature materials and coatings also with additional functional properties such as sensing properties, self-healing capabilities or enhanced strain tolerance. He is also active in the development of functional coatings for solid oxide fuel cells and membranes for oxygen and hydrogen separation. Recently, repair technologies, especially by cold gas spraying, aerosol deposition processes, and coating solutions for alkaline and PEM electrolysis have also been developed.
Memberships
Since 2008: Member of the DIN Standards Committee on Welding and Allied Processes (NAS)
German Ceramic Society (DKG) ()
Gemeinschaft Thermisches Spritzen e.V. (GTS) - Association of Thermal Sprayers
Reviewer for the German research foundation (; ), the Alexander-von-Humboldt-Foundation, the Carl-Zeiss-Stiftung, the AiF, and several national research organizations
Awards
2017: Appointment as Fellow of the American Ceramic Society
2017: Induction into the ASM/TSS Hall of Fame of Thermal Spray
Since 2017: Editor of the Journal of the European Ceramic Society
2019: Appointment as Fellow of ASM/TSS
2019: Elected as a member of the DFG Review Board "Materials Engineering" for "Coating and Surface Technology"
2022: European SOFT Innovation Award (€50,000 prize money) together with scientists of KIT (Kalsruhe Institute of Technology () for the development of plasma sprayed, functionally graded coatings for fusion power plants
Selected publications
with Daniel E. Mack, Martin Tandler, Yoo J. Sohn, Doris Sebold, Olivier Guillon: Unique performance of thermal barrier coatings made of yttria-stabilized zirconia at extreme temperatures (> 1500 °C). In: Journal of the American Ceramic Society, Volume 104, Nr. 1, September 2020.doi.org/10.1111/jace.17452, Pages 463–471.
with Apurv Dash, Olivier Guillon, Jesus Gonzalez-Julian: Molten salt shielded synthesis of oxidation prone materials in air. In: Nature materials. Volume 18, Nr. 5, Mai 2019.doi.org/10.1038/s41563-019-0328-1, Pages 465–470.
with Tobias Kalfhaus, M. Schneider, B. Ruttert, Doris Sebold, T. Hammerschmidt, Werner Theisen, Gunther F. Eggler, Olivier Guillon: Repair of Ni-based single-crystal superalloys using Vacuum Plasma Spray. In: Materials & Design, Volume 168, 15. April 2019.doi.org/10.1016/j.matdes.2019.107656, Page 107656.
with R Singh, S Schruefer, S Wilson, Jens Gibmeier: Influence of coating thickness on residual stress and adhesion-strength of cold-sprayed Inconel 718 coatings. In: Surface and Coatings Technology, Volume 350, September 2018.doi.org/10.1016/j.surfcoat.2018.06.08, Pages 64–73.
with Emine Bakan: Ceramic top coats of plasma-sprayed thermal barrier coatings: materials, processes, and properties. In: Journal of Thermal Spray Technology, Volume 26, Nr. 6, Juli 2017. doi.org/10.1007/s11666-017-0597-7, Pages 992–1010.
with Armelle Vardelle, Christian Moreau, Jun Akedo, Hossein Ashrafizadeh, Christopher C. Berndt, Jörg O. Berghaus, Petri Vuoristo: The 2016 thermal spray roadmap. In: Journal of Thermal Spray Technology, Volume 25, Nr. 8, Dezember 2016.dx.doi.org/10.1007/s11666-016-0473-x, Pages 1376–1440.
with Markus Haydn, Kai Ortner, Thomas Franco, Sven Uhlenbruck, Norbert H. Menzler, Detlev Stöver: Multi-layer thin-film electrolytes for metal supported solid oxide fuel cells. In: Journal of Power Sources, Volume 256, Juni 2014.doi.org/10.1016/j.jpowsour.2014.01.043, Pages 52–60.
with Maria O. Jarligo, Georg Mauer, Martin Bram, Stefan Baumann: Plasma Spray Physical Vapor Deposition of La1-xSrxCoyFe1−yO3−δ Thin-Film Oxygen Transport Membrane on Porous Metallic Supports. In: Journal of thermal spray technology, Volume 23, Nr. 1, 2014.doi.org/10.1007/s11666-013-0004-y, Pages 213–219.
with Xueqiang Cao, Frank Tietz, Debabrata Basu, Detlev Stöver: Zirconates as new materials for thermal barrier coatings. In: Journal of the American Ceramic Society, Volume 83, Nr. 8.doi.org/10.1111/j.1151-2916.2000.tb01506.x, Pages 2023–2028.
with Detlev Stöver: Processing and properties of nanograin silicon carbide. In: Journal of the American Ceramic Society, Volume 82, Nr. 10, Oktober 1999.doi/10.1111/j.1151-2916.1999.tb02127.x, Pages 2585–2593.
References
External links
Profile Robert Vaßen on the Website of Forschungszentrum Jülich
Website Materials Synthesis and Processing (IMD-2) at the Forschungszentrum Jülich
Profile on the platform ORCID
Profile on the Ruhr University Bochum Website
20th-century German physicists
21st-century German physicists
RWTH Aachen University alumni
Materials scientists and engineers
Year of birth missing (living people)
Living people | Robert Vaßen | [
"Materials_science",
"Engineering"
] | 1,629 | [
"Materials scientists and engineers",
"Materials science"
] |
74,766,932 | https://en.wikipedia.org/wiki/Paecilomyces%20dactylethromorphus | Paecilomyces dactylethromorphus is a species of fungus in the genus Paecilomyces in the order of Eurotiales.
References
dactylethromorphus
Fungi described in 1934
Fungus species | Paecilomyces dactylethromorphus | [
"Biology"
] | 49 | [
"Fungi",
"Fungus species"
] |
74,767,555 | https://en.wikipedia.org/wiki/Paecilomyces%20paravariotii | Paecilomyces paravariotii is a species of fungus in the genus Paecilomyces in the order of Eurotiales, closely related to Paecilomyces variotii.
References
paravariotii
Fungi described in 2023
Fungus species | Paecilomyces paravariotii | [
"Biology"
] | 56 | [
"Fungi",
"Fungus species"
] |
74,767,930 | https://en.wikipedia.org/wiki/Where%20Do%20Camels%20Belong%3F | Where Do Camels Belong? is a book by biologist Ken Thompson.
The book examines the science and history of invasive species. The book describes itself as "an examination of the whole question of native and alien species, and what might be called an alien invasions industry—and its implications".
The title of the book is in reference to a question posed on its first page, questioning the reader as to "where camels belong?" as a native species; while pointing out that whilst most associated with the Middle East, camels actually first evolved in North America, are most diverse in South America, and have their only truly wild extant population in Australia.
References
2014 non-fiction books
Biology books
Invasive species
Evolutionary biology
Climate change | Where Do Camels Belong? | [
"Biology"
] | 147 | [
"Evolutionary biology",
"Pests (organism)",
"Invasive species"
] |
74,768,197 | https://en.wikipedia.org/wiki/264%20%28number%29 | 264 (two hundred [and] sixty-four) is the natural number following 263 and preceding 265.
In mathematics
264 is an even composite number with three distinct prime factors (23 × 3 × 11). 264 is a Harshad number in base ten, also divisible by each of its digits.
264 is the sum of all even composite numbers that are not the sum of two abundant numbers (not necessarily distinct): 4 + 6 + 8 + 10 + 12 + 14 + 16 + 18 + 20 + 22 + 26 + 28 + 34 + 46. The only other even number that is not the sum of two abundant numbers is the only even prime number, 2.
References
Integers | 264 (number) | [
"Mathematics"
] | 141 | [
"Elementary mathematics",
"Integers",
"Mathematical objects",
"Numbers"
] |
74,770,329 | https://en.wikipedia.org/wiki/Hand-rearing | Hand-rearing, artificial-rearing, human-rearing or hand-raising is the process of caring for and feeding juvenile animals by humans during a stage when they would normally be fed by their parents.
For the hand-rearing of mammals, a bottle with milk from a female of their species, milk from another closely related species, or an appropriate milk formula can be used.
In the case of birds, in some instances, hand-rearing with puppets that mimic the mother's head with key features to stimulate the chick's beak opening and food ingestion may be necessary.
Hand-rearing can lead to habituation or imprinting of these animals towards humans, with the risk that adults may not exhibit normal behavior towards their species' companions, especially in animals raised for reintroduction into the wild. Potential difficulties include integration into groups of conspecifics, learning natural behaviors such as hunting, choosing a mate, as well as raising their own offspring.
However, in livestock farming and domestic animal breeding, habituating animals to humans can be of great utility.
See also
Artificial incubation
Cross-fostering
Fostering (falconry)
Hack (falconry)
Human-guided migration
Puppet-rearing
References
Animal breeding
Animal reintroduction
Conservation biology | Hand-rearing | [
"Biology"
] | 261 | [
"Conservation biology"
] |
74,771,391 | https://en.wikipedia.org/wiki/Magnesium%20azide | Magnesium azide is an inorganic chemical compound with the formula . It is composed of the magnesium cation () and the azide anions ().
Properties
Magnesium azide hydrolyzes easily. Like most azides, it is explosive.
References
azide
magnesium
Explosive chemicals | Magnesium azide | [
"Chemistry"
] | 57 | [
"Explosive chemicals",
"Azides",
"Inorganic compounds",
"Inorganic compound stubs"
] |
74,771,592 | https://en.wikipedia.org/wiki/Strontium%20azide | Strontium azide is an inorganic chemical compound with the formula . It is composed of the strontium cation () and the azide anions ().
Properties
Strontium azide crystallizes in an orthorhombic Fddd space group. Unlike the azides of alkali metals which have a linear azide ion formation, strontium azide possesses bent azide ions, which can continue to bend further when under higher pressure.
References
azide
strontium
Explosive chemicals | Strontium azide | [
"Chemistry"
] | 105 | [
"Explosive chemicals",
"Azides",
"Inorganic compounds",
"Inorganic compound stubs"
] |
74,771,915 | https://en.wikipedia.org/wiki/Illegal%20character | In computer science, an illegal character is a character that is not allowed by a certain programming language, protocol, or program. To avoid illegal characters, some languages may use an escape character which is a backslash followed by another character.
Examples
Windows
In the Windows operating system, illegal characters in file and folder names include colons, brackets, question marks, and null characters.
References
Character encoding | Illegal character | [
"Technology"
] | 80 | [
"Natural language and computing",
"Character encoding"
] |
74,772,975 | https://en.wikipedia.org/wiki/Chinese%20whole%20characters | A Chinese whole character, or whole Chinese character (Pinyin: hànzì zhěngzì; Traditional Chinese: 漢字整字; Simplified Chinese: 汉字整字), is a complete Chinese character. It lies at the final level of the stroke-component-character Chinese character composition.
According to their structures, Chinese characters can be divided into undecomposable characters (独体字) and decomposable characters (合体字). An undecomposable character is formed by one primitive component and is also called a single-component character, a decomposable character can be decomposed into two or more components and is also called a multi-component character.
Undecomposable characters
Definition
An undecomposable character is directly formed by strokes, can not be decomposed into smaller components, though may be a component of a decomposable character. For example, 人 is an undecomposable characters formed by strokes ㇓ and ㇏, and is used to form character 丛.
Lists of undecomposable characters
The following are some lists of undecomposable characters created by different authors.
"Chinese Character Information Dictionary" (漢字信息字典) contains a total of 7,785 standardized characters in the China Mainland. According to static statistics, there are 323 undecomposable characters, accounting for 4.149%. According to dynamic statistics, undecomposable characters account for 25.910% of the corpus. Because many single-component characters are frequently-used characters. The list of undecomposable characters is as follows (in Pinyin order):
凹八巴白百办半贝本匕币必卞丙秉卜不步才册叉产长厂车臣辰成丞承尺彳斥赤虫丑川巛串垂匆寸大歹丹刀氐电刁丁丢东斗厾不(重)儿而耳发乏凡方飞非丰夫弗甫钆玍丐干甘戈革个艮更工弓瓜广龟果亥禾乎户互幻奂火丌乩及几己夹甲戋兼柬见孑巾斤今堇井九久韭旧臼巨孓开孔口来乐耒礼里力吏隶良两了〇令龙甪乱马买毛矛么门米芈丏免面灭民皿末母木目乃内年廿乜牛农女丬乓皮匹片氕乒平七妻气千羌且丘求虬曲犬冉人壬刃日乳入卅伞丧山上勺少申身甚升生尸失虱十石史豕士氏世事手书术戍束甩水厶司巳肃太天头凸土兔彖屯乇瓦丸万亡王韦为囗卫未我乌无毋五兀勿戊夕西习系下乡象小心戌血丫牙轧亚严央羊么夭也业页曳一夷乙已以乂义弋亦尹引永用尤尢由酉又于予臾禺雨禹玉聿曰月再扎札乍丈爪兆争正之止豸中重舟州朱竹主专隹子自
Su segmented 7,000 commonly-used characters and obtained 233 undecomposable characters, accounting for 3.4%. The list of undecomposable characters is as follows (in stroke-based order):
一乙二十丁厂七卜八人入乂儿九匕几刁了乃刀力又乜三干亍于亏士土工才下寸丈大兀万弋上小口山巾千川彳个么久丸夕凡及广亡门丫义之尸已巳弓己卫孑子孓也女飞刃习叉乡么丰王井开夫天无韦专丐廿木五卅不太犬歹尤车牙屯戈互瓦止少曰日中内水手牛毛气壬升夭长片币爪乏月氏勿丹火为户心尹尺夬丑爿巴书毋玉未末戋正甘世本术丙龙戊平灭东凸业目且甲申电田由央史冉皿凹四生失矢禾丘白斥瓜乎用甩氐乐册主半必永弗出母耒耳亚臣吏再西夹夷曳虫曲朱丢乒乓臼自血甪舟米州聿严甫更束两酉来里串我身系事雨果垂秉臾柬韭禺重禹
In the "Specification of the Undecomposable Characters Commonly Used in the Modern Chinese" (现代常用独体字规范), 256 modern commonly used undecomposable characters have been identified within the scope of modern Chinese characters, forming the "List of Modern Commonly Used Undecomposable Characters". The list of undecomposable characters is as follows (in stroke-based order):
一乙二十丁厂七卜八人入儿匕几九刁了刀力乃又三干于工土士才下寸大丈与万上小口山巾千川个歹久么凡丸及广亡门丫义之尸己已巳弓子卫也女刃飞习叉马乡丰王开井天夫无云专丐木五不犬太歹尤车巨牙屯戈互瓦止少曰日中贝内水见午牛手气毛壬升夭长片斤爪父月氏勿丹鸟六文方火为斗户心尺丑巴办予书玉未末击正甘世本术丙石戊龙平东卡凸业木且甲申电田由史央冉皿凹四生矢失乍禾丘白斥瓜乎用甩乐匆册鸟主立半头必永民弗出矛母耳亚臣吏再西百而页夹夷虫曲肉年朱臼自血卤舟亦衣产亥羊米州农严求甫更束两酉来卤里串我身囱言羌弟事雨果垂秉肃隶承革柬面重鬼禹首兼象鼠
The "List of Commonly Used Character Components" in the "Specification of Common Modern Chinese Character Components and Component Names (现代常用字部件及部件名称规范)" includes a total of 311 commonly used character components, i.e., undecompasable characters. The list of undecomposable characters is as follows (in Pinyin order):
凹八巴白百办半卑贝本匕必丙秉卜不才册叉产长厂车臣辰承尺斥赤虫丑出川串垂匆囱寸大歹丹单刀弟电刁丁鼎东兜斗豆儿而耳二发凡方飞非丰凤夫弗甫父丐干甘高戈革个更工弓谷瓜广龟鬼果亥禾黑后乎互户黄火击及几己夹甲兼柬见角巾斤今金京井九久韭臼巨具卡开口来老乐里力立吏丽隶两了六龙卤鹿卵仑马毛矛卯么门米免面民皿末母木目乃南内年鸟牛农女乓皮片乒平七妻其气千欠且丘求曲去犬冉人壬刃日肉入三伞色山上勺少舌申身升生尸失十石食史矢士氏示世事手首书鼠术束甩永司丝巳四肃太天田头凸土屯瓦丸万亡王卫为未文我乌无五午勿戊夕西习下乡向象小心辛戌穴血熏丫牙亚严言央羊夭也业页一衣夷乙已义亦庸永用尤由酉又于鱼与予雨禹玉曰月云再乍丈爪兆争正之直止至中重舟州朱竹主专子自
Based on the above experimental results, it is estimated that the number of undecomposable characters in modern Chinese characters approximately account for 4%.
Since each experimenting family has slight different understandings of components and often uses different character sets, there are differences in the number of undecomposable characters obtained. But generally speaking the results are quite similar, ranging between over 200 to over 300.
Decomposable characters
Definition
A decomposable character can be decomposed into more than one component. For example, "字" (character) is formed by two components (宀+子).
There are two frequently-used modes of component combination in the study of Chinese character structures: first-level component combination and primitive component combination.
First-level component combination
The first-level component combination mode or pattern is what people often call the structures of Chinese characters. According to this analysis, the structures of decomposable characters can be divided into 4 major categories and 13 subcategories:
Left to right structure
Left to right (⿰, 2FF0 ), for example: 部, 件, 結 and 構.
Left to middle and right (⿲, 2FF2): 衡, 班 and 辯.
Above to below structure
Above to below (⿱, 2FF1): 要, 思 and 想.
Above to middle and below (⿳, 2FF3): 鼻, 曼 and 率.
Surrounding structure
Full surround :
Surrounded from four sides (⿴, 2FF4): 圍, 國 and 囪
Surrounded from three sides
Surround from above (⿵, 2FF5): 問, 同 and 風
Surround from below (⿶, 2FF6): 凶, 画 and 函
Surround from left (⿷, 2FF7): 匡, 匠 and 匣
Surrounded from two sides
Surround from upper left (⿸, 2FF8): 廣, 居 and 病.
Surround from upper right (⿹, 2FF9): 句, 可 and 氧.
Surround from lower left (⿺, 2FFA): 這, 建 and 題.
Surround from lower right (N/A)：斗 and 头.
Overlaid structure
Overlaid (⿻, 2FFB): 巫, 爽 and 承.
Chinese Character Distribution by Structures
The following data is excerpted from "Chinese Character Information Dictionary", with 7,785 Mainland Standard Chinese Character.
List of characters in nested structure
According to statistics from the "Chinese Character Information Dictionary" , there are a total of 49 characters of overlaid (or nested, including fully surrounded) structure among the 7,785 mainland standard characters in the dictionary:
哀褒乘囱囤固国裹回困圃囚圈衰爽四田图团围巫因幽园圆衷噩囟胤兖袤亵裒囝囡囵囫囹囿圄圊圉圜豳囮囷奭圐㘥
If the full surrounded characters are moved to the surrounding category, the overlaid characters will be even less.
Primitive component combination
According to the planar analysis by primitive components, Chinese character structures include the following modes or patterns:
A. For characters composed of two primitive components, there are 9 different structures, as shown by the following example characters: 吕认压达勾问区凶团.
B. For characters composed of three components, there are 21 different structures, such as: 荣花型培树缠抛挺润抠捆部庶厢逞逊闾圄幽乖巫.
C. For characters composed of four components, there are 20 different structures, such as: 营蕊蓝寤嫠筐辔椁摄燃游榧额韶欧剩腐遮阔匿.
D. For characters composed of five components, there are 20 different structures, such as: 赢蒿膏寝蘧嚣篮樊搞澡缀渤漉髂齁敲酃戳魔噩.
E. For characters composed of six components, there are 10 different structures, such as: 臀翳麓瀛灌骥歌豁豌衢.
F. For characters composed of seven components, there are 3 different structures, such as: 戆麟饕.
G. For characters composed of eight components, there is 1 structure, such as: 齉.
H. For characters composed of nine components, there is 1 structure, such as: 懿.
The level to which Chinese character components should be divided must be determined based on specific needs. For example, Chinese character teaching often uses a coarser level of analysis in order to be concise, while component-encoding Chinese character input methods often use relatively detailed analysis in order to reduce coding elements.
Chinese character distribution by numbers of components
The following data is excerpted from "Chinese Character Information Dictionary". The components here refer to primitive components.
The static distribution is mainly concentrated in the number of components 2, 3, and 4; the dynamic distribution is mainly concentrated in the number of components 1, 2, and 3.
In both dynamic and static distribution statistics, more than 99% of the characters have less than 5 primitive components.
Note that the static component counts for component numbers 1 and 5 are the same, but their dynamic component counts are very different.
Chinese character fonts
Fonts
The popular fonts of modern Chinese characters include Song or Ming (宋體, 明體), FangSong (仿宋體), Kai (regular, 楷體), Li (clerical, 隸體), Hei (black, sans-serif, 黑體) and Wei (魏體).
The official standard fonts include
China Mainland: List of Commonly Used Standard Chinese Characters (通用规范汉字表)
Taiwan: Chart of Standard Forms of Common National Characters (常用國字標準字體表)
Hong Kong: List of Graphemes of Commonly-Used Chinese Characters (常用字字形表),
Unicode CJK Unified Ideographs
Font sizes
Internationally, font sizes are generally measured by "points".
In China, in addition to the "points" measure system, a unique "number" system is also used for Chinese characters. For example, the simplified Chinese version of MS Word allows setting font sizes by points or by numbers.
The point system
After nearly three hundred years of development and improvement, the most influential writing point standards in the world now include the Didot point system in continental Europe (one point is approximately 0.3759 mm) and the Anglo-American point system (one point is approximately 0.3515 mm). China uses the latter point system.
The available point values on MS Word are all numbers between 1 point and 1638 points that are divisible by 0.5, that is, the set {1, 1.5, 2, 2.5, ..., 1637, 1637.5, 1638}. These regulations can be verified directly on the computer.
The number system
The font size options provided by the simplified Chinese version of Windows and Word are arranged in ascending order of font sizes:
No. 8 (八号), No. 7 (七号), Small No. 6 (小六号), No. 6 (六号), Small No. 5 (小五号), No. 5 (五号), Small No. 4 (小四号), No. 4 (四号), Small No. 3 (小三号), No. 3 (三号), Small No. 2 (小二号), No. 2 (二号), small No. 1 (小一号), No. 1 (一号), Small initial number (小初号), Initial number (初号).
"No. 8" (or size 8) is the smallest, equivalent to 5 points (British and American system), and the font height is about 1.757mm; "Initial number" (or size A) is the largest, equivalent to 42 points, and the font height is about 14.761mm.
Number-point correspondence
The following is a Chinese character font size "number-point" corresponding table created by Dr. Zhang.
See also
Chinese character strokes
Chinese character components
Modern Chinese characters
List of CJK fonts
References
Works cited
Notes
External links
https://www.unicode.org/charts/PDF/U2FF0.pdf
Whole characters | Chinese whole characters | [
"Technology"
] | 3,365 | [
"Components",
"Chinese character components"
] |
74,773,534 | https://en.wikipedia.org/wiki/Jet%20fire | A jet fire is a high temperature flame of burning fuel released under pressure in a particular orientation. The material burned is a continuous stream of flammable gas, liquid or a two-phase mixture. A jet fire is a significant hazard in process and storage plants which handle or keep flammable fluids under pressure. The heat flux of the jet flame can cause rapid mechanical failure thereby compromising structural integrity and leading to incident escalation.
Context
The Piper Alpha disaster in 1988 demonstrated how the accidental release of hydrocarbon can lead to the catastrophic failure of an installation with the rupture of major pipeline risers. Jet fires impinged on vessels, pipework and firewalls. Under these conditions the fireproofing material was compromised within a few minutes rather than one to two hours, which had been specified. Even without direct impingement, the high thermal radiation emitted by jet flames also affected plant and would have been fatal to personnel.
Characteristics
A jet fire, also known as a spray fire if the fuel is a liquid or liquefied gas, is a turbulent diffusion flame of flammable material. The characteristics of a jet fire depend on a number of factors. These include: fuel composition; release conditions; release rate; release geometry; direction; and ambient wind conditions.
For full details of the mechanism and structure of jet fires see High Pressure Jet.
Some characteristics of specific jet fires are:
Sonic releases of natural gas are characterized by high velocity, low buoyancy flames that are relatively non-luminous with low radiative energy,
A jet flame of higher hydrocarbons is lazy, buoyant, luminous, with the presence of black smoke at the tail of the flame, they are highly radiative,
The surface emissive power (SEP) of jet flames is in the order of 200 kW/m2 to 400 kW/m2. Such flames have a temperature of 1350 °C. These high heat fluxes can readily compromise the integrity of structures and vessels and can lead to mechanical failure of plant and equipment.
A jet fires is a particular hazard to personnel. People are able to survive and escape from exposure to heat fluxes less than 5 kW/m2, while higher fluxes can be fatal.
Designing for jet fires
Process plant is generally protected by a pressure relief system. However, local heating of a pressure vessel by a jet fire may compromise the integrity of the vessel before the pressure relief device operates. The measures taken for protection against jet fires are as follows:
Prevention of leaks using effective maintenance
Flange orientation and elimination
Blowdown systems, to reduce the inventory and pressure in the plant
Isolation of leaks
Robust external insulation
Emergency response
Water deluge can reduce the heat loading of plant so that its temperature is maintained below that at which failure occurs, or that the temperature rise is sufficiently reduced such that shutdown and depressurization can take place.
Older plants may have been sized on an earlier version of the American Petroleum Institute's Pressure-Relieving and Depressuring Systems standard, which did not include consideration of jet fires.
The international standard publication ISO 22899 (Determination of the Resistance to Jet Fires of Passive Fire Protection Materials) sets requirements for the specification of passive fire protection against jet fires.
See also
High pressure jet
Process hazard analysis
Process safety
References
Industrial fires and explosions
Process safety
Types of fire
Combustion | Jet fire | [
"Chemistry",
"Engineering"
] | 674 | [
"Industrial fires and explosions",
"Safety engineering",
"Combustion",
"Process safety",
"Explosions",
"Chemical process engineering"
] |
74,774,113 | https://en.wikipedia.org/wiki/Greenbelt%20scandal | The Greenbelt scandal is a political controversy in the Canadian province of Ontario about the Greenbelt.
Background
Shortly before the 2018 Ontario general election, a leaked video of Progressive Conservative Party politician Doug Ford showed him promising that he would "open up a big chunk of the Greenbelt," a nature reserve in Southern Ontario's Golden Horseshoe region, to real estate developers. In response to widespread criticism, Ford claimed that he had reversed his position and would not modify the area.
Controversy
Following a successful re-election campaign in the 2022 Ontario general election, Ford used his authority as Premier of Ontario to shift 7,400 acres outside the Greenbelt reserve, while adding 9,400 acres of land into the environmentally protected area in December 2022. The decision led to a political scandal, as some real estate developers had purchased property in the Greenbelt reserve shortly before the changes were announced. Furthermore, some of the implicated developers had attended Ford's daughter's August 2022 pre-wedding party, which Ford defended based on the preclearance he had received from the province's Integrity Commissioner in January 2022.
Seven companies owned by the De Gasperis family, including Tacc Construction, Arista Homes, and Leslie Elgin Developments, had planned to build in Richmond Hill, Ontario. President Michal Rice of Green Lane Bathurst planned to begin building in King, Ontario, President Marcelo Perez-Hassaf of Torca II announced construction projects in Stouffville through their 2502536 Ontario numbered company, Flato Upper Markham Village and Minotar Holdings held sites in Markham, President Peter Tanenbaum of Nash Road Developments announced construction projects in Clarington, and a Chinese firm based in Fuyang announced plans to build in Ajax.
The Ontario Provincial Police transferred its anti-racketeering investigation to the Royal Canadian Mounted Police (RCMP) in August 2023 to avoid a conflict of interest. In October 2023, the RCMP announced they were opening a criminal investigation into whether Ford's changes corruptly favored certain developers.
In August 2023, the Auditor General of Ontario released a report detailing how the provincial government's approvals had favoured certain developers that stood to earn over $8 billion, while failing to consider the developments' environmental, agricultural, and financial impacts.
Fallout
Housing Minister Steve Clark resigned in September 2023 after the province's Integrity Commissioner concluded that he had violated ethics rules in his approvals of real estate development projects. While announcing his resignation, he resisted calls from First Nations representatives seeking traditional territories to be returned to the Greenbelt. Later that month, Public and Business Service Delivery Minister Kaleed Rasheed resigned over his relationship with a developer involved in the Greenbelt scandal. Clark and Rasheed's resignations led Ford to reverse his changes, announcing that he would instead encourage building within existing urban areas.
Reversal
In October 2023, Clark's successor as Housing Minister, Paul Calandra, introduced a bill to restore the Greenbelt's original boundaries and require future changes to be approved by the Ontario Legislative Assembly, which was passed in December 2023.
See also
Ontario minister's zoning orders controversy
References
Politics of Ontario
Zoning
Political scandals in Canada
Premiership of Doug Ford | Greenbelt scandal | [
"Engineering"
] | 649 | [
"Construction",
"Zoning"
] |
74,774,369 | https://en.wikipedia.org/wiki/Huawei%20Mate%2060 | The Huawei Mate 60 and Mate 60 Pro / Pro+ / RS is a high-end 2023 smartphone product of the Chinese Huawei corporation from its Huawei Mate series. It has a Kirin 9000s SoC chipset designed by HiSilicon and produced by the SMIC foundry. The device supports satellite network communications and 5G.
Technology
Processors
The Huawei Mate 60 is the first Huawei smartphone to feature a 7nm SoC designed and manufactured in mainland China, despite the imposition of US sanctions on the company.
The CPU HiSilicon Kirin 9000S is a SoC supposed to consist of four high-performance cores (one at up to 2.62 GHz and three at up to 2,150 MHz) that is based on HiSilicon's custom TaiShan microarchitecture and four energy-efficient cores (up to 1,530 MHz) based on ARM's Cortex 510. The smartphone also uses the Maleoon 910 graphics processing unit operating at up to 750 MHz.
Network communications
According to third-party testing, after plugging in the SIM card the network standard indication of the phone does not show a 5G connection, and Huawei does not mention supporting 5G in the parameter details; the actual network speed test shows that its performance is 5G. Reports also believe that it has the ability to support 5G.
Huawei focuses more on promoting its capabilities as a satellite communication terminal. The Mate 60 series smartphone supports satellite call functions through the Tiantong system, and short message sending and receiving functions through the Beidou system.
Mate 60 also supports NearLink, a short-range wireless communication technology that combines the features of Bluetooth and Wi-Fi with enhanced prerequisites, and can be used in the future on Internet of Things and Internet of Vehicles.
Camera
At the end of 2023, Huawei Mate 60 Pro+ was the best smartphone camera in the world according to DxOMark.
Reception
The launch of the Huawei Mate 60 garnered significant attention, and was widely touted as a victory against US government sanctions intended to stop Chinese companies from producing or obtaining advanced chips. Huawei's breakthrough raised concerns within the US government that technological restrictions alone were unable to prevent Huawei from obtaining advanced chips: the U.S. Department of Commerce launched an investigation into the situation at the end of 2023.
On 5 March 2024, a report by Counterpoint Research claimed that although overall Chinese smartphone sales were 7% lower in the first six weeks of 2024, compared with the same period in 2023, Apple’s recently launched flagship iPhone 15 was selling exceptionally badly, with Apple’s overall smartphone unit sales falling 24% in the relevant period, because buyers were turning towards devices made by Huawei. According to Counterpoint Research, Huawei saw unit sales rise by 64% in the period.
Impact in China
Huawei had told their customers that stores in Shenzhen would only have a certain amount of phones to sell, which resulted in long lines outside of every store. On August 30, 2023, Huawei Mall launched the Mate 60 pre-order page. On September 3 of that same year, the Mate 60 Pro was fully on-sale. At 18:08, online platforms such as Huawei Mall, Taobao, Tmall, and JD.com sold out all available colors in just one minute after opening sales to the public. There were also lines of people waiting to buy at Huawei stores across China. On September 8, Huawei Mall launched the Mate 60 Pro+ pre-order page.
References
External links
HUAWEI Mate 60 official website
HUAWEI Mate 60 Pro official website
HUAWEI Mate 60 Pro+ official website
Huawei smartphones
Mobile phones introduced in 2023
Flagship smartphones
Android (operating system) devices
Mobile phones with multiple rear cameras
Mobile phones with 4K video recording | Huawei Mate 60 | [
"Technology"
] | 783 | [
"Phablets",
"Crossover devices",
"Flagship smartphones"
] |
69,003,912 | https://en.wikipedia.org/wiki/ASKAP%20J173608.2%E2%80%93321635 | ASKAP J173608.2–321635 is an unidentified astronomical radio source that sends "radio signals … from the direction of the Centre galaxy". It is nicknamed "Andy's Object" after its discoverer, Ziteng (Andy) Wang, from the University of Sydney in Australia. The object was detected using the Australian Square Kilometer Array Pathfinder and MeerKAT radio telescopes. It is not visible to "the most powerful non-radio telescopes" and was detected six times between 2020 January and 2020 September. This may be a new class of object because no counterpart has been detected at multiple wavelengths, which "rules out flaring stars, binary systems, NSs, GRBs, or supernovae as its source". The radio emissions exhibit a high level of polarization, suggesting scattering as a result of a black hole.
References
Astronomical radio sources
Scorpius
University of Sydney | ASKAP J173608.2–321635 | [
"Astronomy"
] | 187 | [
"Astronomical radio sources",
"Astronomical events",
"Astronomy stubs",
"Constellations",
"Scorpius",
"Astronomical objects"
] |
69,004,333 | https://en.wikipedia.org/wiki/Organic%20selenocyanates | Organic selenocyanates are organoselenium compounds with the general formula RSeCN. They are generally colorless, air-stable solids or liquids with repulsive odors. In terms of structure, synthesis, and reactivity, selenocyanates and thiocyanates behave similarly.
Preparation
Alkyl selenocyanates are generally prepared by treatment of potassium selenocyanate with alkyl halides in alcohol or acetone solution. Aryl selenocyanates are generally prepared by treatment of potassium selenocyanate with aryl diazonium salts.
Reactions
Organic selenocyanates can be reduced to the selenol, which readily oxidize to the diselenide:
RSeCN + 2e− → RSe− + CN−
RSe− + H+ → RSeH
2 RSeH + 0.5O2 → RSeSeR + H2O
Oxidation of selenocyanates gives the seleninic acids.
References
Functional groups | Organic selenocyanates | [
"Chemistry"
] | 212 | [
"Selenocyanates",
"Functional groups"
] |
69,004,500 | https://en.wikipedia.org/wiki/Dana%20G.%20Goski | Dana Grace Goski (born 1967) is a Canadian-born materials scientist, past president (October 2020–October 2021) of The American Ceramic Society (ACerS), and vice president of research & development at Allied Mineral Products, Inc. During her tenure as ACerS president, she extensively supported the mission and activities of the Society's Diversity & Inclusion Subcommittee and the International Ceramic Arts Network (ICAN), the Society's member organization for clay artisans and potters.
Education
Goski was born in Nova Scotia, Canada. She received her early education at Royal Canadian Air Force Base schools and finished high school in the Nova Scotia public school system. After graduation, she studied chemistry at Dalhousie University in Nova Scotia where she received her B.Sc. in 1989 and M.Sc. in 1992 as a joint project with the National Research Council of Canada (NRC) with a focus on colloidal processing and surface chemistry of alumina and zirconia systems. In 1997, she completed her Ph.D. at the Technical University of Nova Scotia and published her thesis Development of an alumina-mullite composite by reaction sintering.
Career
In 1996, Goski moved to Columbus, Ohio, to join Allied Mineral Products, a global producer of monolithic refractory materials, as a senior research engineer and technical consultant. In 2009, she was named director of research and development before becoming vice president of research and development in 2018 at Allied, where she guides research in advanced ceramic composites and refractory materials.
Goski was named a Fellow of The American Ceramic Society in 2015, awarded the St. Louis Section Theodore J. Planje Award in 2019, and the Marquis Award in 2020.
Awards and recognition
Her patented work on monolithic graphitic castable was recognized with the 2015 ACerS Corporate Technical Achievement Award, given to the Allied Mineral Products team in relation to Goski's patent. In 2019, she was recognized with the Theodore J. Planje Award, given for distinguished achievement in the field of refractories, by the St. Louis Section of ACerS.
For her support of leadership priorities, identification of strategic approaches, and ability to rally people together to achieve significant milestones, she was honored with the ACerS Global Ambassador Award (2019). In 2020, Goski was awarded with the John Marquis Memorial Award for her work published in ACerS journals and related to manufacturing in ceramics and glass.
2015 Fellow of The American Ceramic Society
2015 ACerS Corporate Technical Achievement Award
2019 Theodore J. Planje Award
2019 ACerS Global Ambassador Award
2020 John Marquis Memorial Award
2020–2021 President of The American Ceramic Society
2022 First woman designated as a Distinguished Life Member of the Unified International Technical Conference on Refractories (UNITECR)
References
Canadian emigrants to the United States
Dalhousie University alumni
Fellows of the American Ceramic Society
Canadian materials scientists
Living people
Women materials scientists and engineers
Scientists from Nova Scotia
1967 births | Dana G. Goski | [
"Materials_science",
"Technology"
] | 602 | [
"Women materials scientists and engineers",
"Materials scientists and engineers",
"Women in science and technology"
] |
69,005,061 | https://en.wikipedia.org/wiki/Low-nutrient%2C%20low-chlorophyll%20region | Low-nutrient, low-chlorophyll (LNLC) regions are aquatic zones that are low in nutrients (such as nitrogen, phosphorus, or iron) and consequently have low rate of primary production, as indicated by low chlorophyll concentrations. These regions can be described as oligotrophic, and about 75% of the world's oceans encompass LNLC regions. A majority of LNLC regions are associated with subtropical gyres but are also present in areas of the Mediterranean Sea, and some inland lakes. Physical processes limit nutrient availability in LNLC regions, which favors nutrient recycling in the photic zone and selects for smaller phytoplankton species. LNLC regions are generally not found near coasts, since coastal areas receive more nutrients from terrestrial sources and upwelling. In marine systems, seasonal and decadal variability of primary productivity in LNLC regions is driven in part by large-scale climatic regimes (e.g. El Niño-Southern Oscillation) leading to important effects on the global carbon cycle and the oceanic carbon cycle.
The naming of these regions follows the same format as the more widely known high-nutrient, low-chlorophyll (HNLC) regions, which display high macro-nutrient concentrations but unusually low primary production and chlorophyll concentrations, usually due to lack of micro-nutrients, usually iron-limitation. While the LNLC terminology appears synonymous with oligotrophic, literature in recent decades has predominantly used the term to define oligotrophic ocean areas (as opposed to lakes, rivers, or other bodies of water) in discussions about dust and iron fertilization. Occasionally, LNLC refers to “low nitrate, low chlorophyll,” which has a similar meaning.
Chlorophyll and primary production
Chlorophylls are the light harvesting pigments employed in photosynthesizing organisms that facilitate the conversion of light into cellular energy for synthesis of organic matter. In aquatic systems, chlorophyll concentrations are frequently used as a proxy measurement for photosynthetic plankton (phytoplankton) abundance and thus the amount of primary production. Chlorophyll concentrations can serve as an estimate for primary productivity.
Primary production is the process of converting CO2, either gaseous or aqueous, and other elements into organic compounds. The extent of global primary production therefore controls how much energy is available to in the biosphere. Most primary production in the ocean occurs via photosynthesis, by organisms called phototrophic primary producers. Phototrophs are the foundation of most aquatic food webs, and primary production in the ocean accounts for about half of Earth's carbon fixation.
In addition to light and CO2, photosynthesis requires nutrients, such as nitrate, phosphate, silicate, and iron in order for phytoplankton to grow. Primary productivity is therefore controlled by the availability of the limiting nutrient (Liebig's law of the minimum). The Redfield Ratio (106C:16N:1P) describes the general relative proportions of carbon, nitrogen, and phosphorus found in marine biomass. If a given region is limited by a nutrient, the relative proportion of nutrients can deviate from the Redfield Ratio. Due to the low nutrient levels in LNLCs, primary production in these regions is usually limited by one or more nutrients.
Physical and biological determinants of nutrient cycling
Phytoplankton growth occurs in the upper ocean, or mixed layer, where sufficient light energy is available and turbulent mixing near the surface increases vertical homogeneity in ocean tracers like temperature, salinity, and density. Nutrient availability in the mixed layer, often a limiting factor for phytoplankton growth, is derived from three primary sources: 1) reintroduced nutrients from deep ocean water that is mixed into surface waters (i.e., new production), 2) recycled nutrients in the surface ocean (i.e., regenerated production), also known as the regeneration loop, and 3) ‘external’ nutrients introduced from terrestrial or atmospheric input and/or biological processes (such as, nitrogen fixation). LNLC regions result from a combination of processes that limit nutrient availability, primarily: the biological pump, Ekman downwelling, and stratification. The biological pump creates a nutrient gradient, or nutricline, in LNLC regions by exporting organic matter from the surface ocean to the deep ocean before that organic matter (OM) can be respired in the photic zone, thus also exporting the OM-associated nutrients from the photic zone. Nutrients transported to depth below the pycnocline can be reintroduced to the surface through ocean mixing processes (including Ekman upwelling and turbulent diffusion) that bring deep, nutrient-rich waters back to the ocean surface and stimulate primary production. LNLCs don't generally occur in regions with significant upwelling or turbulent diffusion because these areas generally see greater nutrient availability and thus primary production.
Lack of reintroduced nutrients can be exacerbated by Ekman downwelling, caused by convergent wind forcing and Ekman transport, which moves water masses downward and removes nutrients from the surface ocean by exporting them out of the photic zone. Downwelling locations are prime LNLC regions, like coastal areas with landward Ekman transport or subtropical gyres.
Stratification of the water column due to density gradients associated with temperature (see thermocline) or salinity (see halocline) also limits reintroduced nutrients from deep water by creating less dense water above more dense water that prevents ocean mixing, only allowing minimal nutrient delivery through the slower turbulent diffusion rates. Physical mixing processes caused by wind or storm events may however introduce nutrients from deeper in the water column into the photic zone and stimulate transient phytoplankton blooms.
While primary production is limited in downwelling or stratified LNLC regions, other nutrient sources become important for maintaining phytoplankton growth, like recycled surface water nutrients and external nutrients (aforementioned sources 2 and 3). Lower nutrient levels favor the growth of picophytoplankton, whose small size increases heterotrophic nutrient recycling (known as the microbial loop) and reduces the loss of nutrients from the biological pump due to the slower sinking rates of smaller particles.
In order to compensate for the low nitrogen/nutrient availability, nitrogen fixation is favored as a mechanism for bringing ‘external’ nutrients into the surface ocean. Nitrogen fixation is the microbial mediated process that converts biologically unavailable dissolved nitrogen gas, which is readily available in the atmosphere and mixed into oceans through diffusion and wave action mixing, into biologically available ammonium. Catalyzed by the enzyme nitrogenase, nitrogen fixation requires iron and often solar energy, making iron a common limiting nutrient in LNLCs. In areas far from terrestrial sources, iron is predominantly delivered through aeolian dust, naturally derived from arid landmasses (e.g. deserts) or volcanic eruptions, that can travel long distances to supply this critical micronutrient to LNLC regions like open ocean gyres.
Productivity in LNLC regions
LNLC regions are estimated to cover around 75% of the global ocean, and despite the generally low per area rates of primary production, an estimated 40% of global ocean productivity occurs in these locations due to their large geographic extent.
A majority of the ocean's LNLC regions are within subtropical gyres, although the Mediterranean Sea is another large LNLC region (for more see Example section). In general, LNLC regions have relatively warm, stratified water columns that limit the delivery of new nutrients to the photic zone via upwelling, thus favoring the nutrient “regeneration loop” where the majority of nutrients are recycled between primary producers, grazers and heterotrophic bacteria. Because the regeneration loop is favored in LNLC regions, there are low rates of new production and limited organic matter exported via the biological pump. However, these regions can experience seasonal and episodic nutrient delivery events that increase primary productivity, favoring the “export pathway” (biological pump), where both dissolved and particulate organic matter exit the system, some of which is sequestered in the deep ocean.
In subtropical gyres, and more generally in areas with low nutrient availability, phytoplankton communities are generally dominated by picoplankton (cells between 0.2 and 2μm). Picoplankton are smaller than other plankton that dominate higher nutrient regions, and their small volume means they have a larger surface area to volume ratio. Picoplankton can therefore take up nutrients more efficiently than larger plankton with smaller surface area to volume ratios. Picoplankton in subtropical gyres are highly grazed upon by nano- (2-20μm) and micro- (20-200μm) plankton, resulting in fast nutrient cycling, especially of nitrogen and phosphorus, and less export of organic matter and associated nutrients to the deep ocean via the biological pump.
Vertical mixing of the water column in winter and spring from storms in LNLC regions can deliver nutrients from deeper in the water column and favor transient increases in primary productivity within ocean gyres. During these events, larger phytoplankton species, such as diatoms, are favored when more nutrients are present, resulting in increased rates of organic matter export to the deep ocean via sinking particulates.
While generally low, observed primary productivity in gyres is higher than would be expected based on measured nutrient supply. The excess primary production can be explained by nitrogen fixing organisms that supply the remaining bioavailable nitrogen needed to support observed seasonal primary productivity. Low organic nitrogen levels in surface waters selects for nitrogen-fixing bacteria called diazotrophs. Nitrogen fixing organisms are often iron limited because nitrogenase has two iron-sulfur clusters. Thus, iron delivery via aeolian dust is often associated with increased primary productivity in the subtropical gyres and in the Mediterranean Sea.
Variability of LNLC regions
Even with their overall low nutrient availability, LNLC regions are dynamic and experience seasonal variability in size and productivity. For example, the size of the North Atlantic Subtropical Gyre shrinks in winter and expands in summer. Long-term trends indicate that subtropical gyres in the northern hemisphere (North Pacific and North Atlantic) are expanding over time, and the subtropical gyres in the southern hemisphere (South Pacific) are growing weaker and more inconsistent. All LNLC subtropical gyres appear to have long-term trends of increasing sea-level height anomalies (SLA) and sea surface temperature (SST). Increasing SLA is indicative of deepening of both the thermocline and the nutricline, which reduces light and nutrient availability for the phytoplankton community in the mixed layer. Increased SST within LNLC regions contributes to increased stratification of the water column, which generally reduces nutrient inputs to the photic zone from deeper waters. Natural climatic variability events such as El Nino/Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO) influence SST in the global ocean with implications for primary productivity and phytoplankton communities. For example, the PDO warm phase increases SST in the equatorial pacific, causing increased stratification of the surface ocean that reduces nutrient availability and favors nitrogen fixing organisms.
Seasonal, decadal, and climate change driven variability in nutrient delivery and productivity in subtropical gyres are the subject of ongoing research efforts, as gyres play an important role in the global carbon cycle via the export of organic carbon from the surface ocean. As oceans warm due to climate change and thermal stratification increases, there is concern that all LNLC regions may become more oligotrophic and that other regions in the tropical and subtropical ocean may shift towards lower productivity LNLC systems. The influence of aeolian dust deposition on primary productivity in LNLC regions is also predicted to increase, as more frequent and higher intensity storm events and increasing aridity due to climate change deliver more dust to the ocean. Increased dust delivery to stratified and nitrogen-limited surface waters would favor nitrogen fixing organisms, such as diazotrophs, which would change the existing phytoplankton community structures and increase N2-associated primary productivity.
Example LNLC regions
North Atlantic Subtropical Gyre
The Sargasso Sea is the region at the center of the North Atlantic subtropical gyre. Although the Sargasso Sea is generally oligotrophic, rates of primary production are much higher than would be expected of a region with limited nutrients, due to nitrogen fixation, physical forces, and seasonal dynamics. The North Atlantic receives a supply of phosphate (PO43-) from the Arctic Ocean, while nitrate (NO3−) is produced by the nitrogen fixing cyanobacteria, Trichodesmium. Nitrogen fixation relies on a supply of iron (Fe), which is delivered to the Sargasso Sea via dust from the Sahara Desert. Nitrogen fixation rates in the region have increased since the 1970s, in part fueled by an increase in iron deposition due to expansion of the Sahara Desert. Wind-driven downwelling removes nutrients from the surface, but mesoscale eddies transport some of these nutrients back to the photic zone. Additionally, strong vertical mixing in the winter and spring brings nutrients to the photic zone, which causes a spring bloom of phytoplankton. Photosynthesis near the bottom of the photic zone, as opposed to closer to the surface, has also been shown to be an important contributor to primary production in the Sargasso Sea.
North Pacific Subtropical Gyre
The North Pacific Subtropical Gyre (NPSG) is one of the ocean's largest of the gyres. Primary production in these oligotrophic waters is generally limited by nitrogen, followed by phosphorus and iron. The NPSG's salinity stratification creates a two-layer ocean in which the upper layer (0–80 m) of the water column is nutrient limited and primary production is supported by nitrogen fixation and recycled nutrients, while the lower layer's production is light limited. Seasonal and decadal climatic events (ENSO and PDO) affect sea surface temperature and other nutrient patterns, influencing biological processes. For example, during the 1997-1998 ENSO event, NO3−-based production accounted for a larger fraction of primary production while particulate carbon export increased. This LNLC region is relatively well studied through the Hawaii Ocean Time-series (HOT) monitoring program (see Monitoring section).
South Pacific Subtropical Gyre
The South Pacific Subtropical Gyre lies in one of the most remote regions of the ocean, and consequently it has been poorly studied. From the studies that have investigated this region, we know that nitrogen is the most limiting nutrient, followed by phosphorus. Input of iron via dust transport is very limited to this region because of its distance from major landmasses. This aeolian flux of iron is 1 to 2 orders of magnitude lower than the central Atlantic and the concentration of dissolved iron across the gyre is only ~0.1 nM. For comparison, the average iron concentrations in the open ocean is ~0.7nM. Despite the low iron concentrations, only the border of the gyre demonstrates iron limitation, while the center does not. It's theorized that this is due to the high stability of the SPSG, which has allowed for phytoplankton populations to adapt to the highly oligotrophic conditions.
Mediterranean Sea
The Mediterranean Sea is generally oligotrophic with a strong west to east gradient of increasing oligotrophy; nutrients, chlorophyll-a concentrations, and rates of primary production all decrease from west to east. While most regions of the ocean are nitrogen-limited, the Mediterranean Sea is generally phosphorus-limited. The biogeochemical characteristics of the Mediterranean Sea are enforced by its anti-estuarine circulation: nutrient-depleted surface water from the Atlantic Ocean enters the Mediterranean via the Strait of Gibraltar, and dense, saline intermediate water formed in the eastern Mediterranean flows westward back into the Atlantic Ocean. This anti-estuarine circulation occurs because net evaporation in the Mediterranean is greater than net precipitation. In addition, because there is limited upwelling, bioavailable nutrients in the intermediate water are transported out of the Mediterranean Sea, leaving the surface water nutrient-depleted.
Monitoring LNLC regions
Monitoring the characteristics of LNLC regions in the ocean is difficult due to the size, remoteness, and conditions of the regions. The ocean is a challenging environment for data collection because instruments and systems must withstand harsh conditions. Additionally, robust data collection and observation requires adequate funding and cooperation among nations and organizations, which has been difficult to achieve. Despite these challenges, there are collaborative projects and stations that utilize both in-situ and remotely sensed data to monitor the conditions of the global ocean.
Satellite instruments
Satellite imagery provides large-scale data to monitor the extent and characteristics of the subtropical gyres, and more broadly, the global oceans. Sensors used for ocean monitoring have spatial resolutions (pixel size) ranging from 200 meters to 4 kilometers, and have revisit frequencies ranging from 10 minutes to multiple days. Ocean color radiometry involves measuring the reflectance of light from ultraviolet, visible, and infrared regions of the electromagnetic spectrum. These data can be used to calculate chlorophyll-a concentrations after correcting for variables such as atmospheric scattering. Remotely-sensed ocean color data is calibrated and validated by in-situ measurements using various instruments, including MOBY (marine optical buoy), a sensor deployed near Lanai, Hawaii that measures light near and at the surface of the water. For a more comprehensive description of satellite instruments used for ocean color analysis, see ocean color.
Seagoing instruments and methods
Many types of instruments can be used to collect in-situ samples and data from the ocean. These instruments can be deployed on board ships, on moorings, on floats or drifters, and on ROVs. Example instruments and methods of collection include, but are not limited to, the following:
CTD
CTD rosette
Bathythermograph (XBT)
Sonar/sound systems
Meteorological instruments
Productivity arrays
Sediment traps
Monitoring stations and programs
Station ALOHA (A Long-term Oligotrophic Habitat Assessment)
In 1988, Station ALOHA (A Long-term Oligotrophic Habitat Assessment) was established by the University of Hawaii with funding from the National Science Foundation. The goal of ALOHA is to collect data over a long temporal scale to better understand the physical and biogeochemical dynamics of the North Pacific Subtropical Gyre. The deep-water station () is the primary site for the HOT (Hawaii Ocean Time-series) program and provides researchers with water column data, including the thermohaline structure, primary production measurements, and chemical composition. Additionally, a collaborative project between the Woods Hole Oceanographic Institution and HOT, called WHOTS, collects data at an ALOHA surface mooring. WHOTS provides the atmospheric and upper-ocean data to HOT, including heat, water, and chemical fluxes between the ocean and atmosphere.
BATS (Bermuda Atlantic Time-series Study)
In 1988, BATS (Bermuda Atlantic Time-series Study) was established by the Bermuda Institute of Ocean Sciences to examine the oceanography and biogeochemical processes in the Sargasso Sea. The goal of BATS is to understand the role of the Sargasso Sea, and more broadly the North Atlantic Ocean, in the global carbon cycle. BATS is one of three time-series studies in the Sargasso Sea near Bermuda; Hydrostation 'S' collects physical oceanography data, and the OFP (Ocean Flux Program) focuses on particle transport in the region.
Mediterranean programs
MOOSE (Mediterranean Ocean Observing System for the Environment) is a France-based network of near-shore and off-shore stations that monitor the northwest Mediterranean Sea. The main purpose of MOOSE is to provide long time-series data for the study of the hydrologic cycle, marine ecosystems, and biogeochemical properties of the northwest Mediterranean.
MONGOOS (Mediterranean Oceanography Network for the Global Ocean Observing System) was established in 2012 as an extension of the Global Ocean Observing System (GOOS). MONGOOS is a collaborative network of over 40 European institutions with the goal of improving oceanographic research in the Mediterranean.
References
Wikipedia Student Program
Aquatic ecology
Planktology
Oceanography | Low-nutrient, low-chlorophyll region | [
"Physics",
"Biology",
"Environmental_science"
] | 4,267 | [
"Hydrology",
"Applied and interdisciplinary physics",
"Oceanography",
"Ecosystems",
"Aquatic ecology"
] |
69,005,591 | https://en.wikipedia.org/wiki/TOI-4138%20b | TOI-4138 b is a transiting exoplanet orbiting the G-type subgiant TOI-4138 1,674 light years away in the northern circumpolar constellation Ursa Minor.
Discovery
The planet was discovered by TESS using the transit method, which involves measuring light curves during a planet’s eclipse. The paper states that it’s inflated due to heating from its host star, which has a high luminosity. Its discovery was announced in October 2021.
Properties
Orbit and mass
TOI-4138 b has an orbital period of 3.6 days, typical for a hot Jupiter. This corresponds to a separation from its host close to one eighth of the distance of Mercury from the Sun. Since the inclination is known, doppler spectroscopy measurements give the planet a mass only 67% that of Jupiter. Its separation is comparable with HD 209458 b, but is much larger due to the evolved state of the host star.
Radius and density
TOI-4138 b’s transit gives it a radius 1.49 times that of Jupiter; this combined with its low mass of gives it a density only 25% that of water.
Host star
TOI-4138 b orbits TOI-4138, a subgiant star located in the constellation Ursa Minor. The star has an enlarged radius of , a luminosity of and an effective temperature of . It has 1.32 times the Sun's mass, and it has an intermediate age of around 3.5 billion years. The apparent magnitude of the star is 11.8, making it not visible to the naked eye.
References
Exoplanets discovered in 2021
Hot Jupiters
Ursa Minor
Transiting exoplanets
Exoplanets discovered by TESS | TOI-4138 b | [
"Astronomy"
] | 361 | [
"Ursa Minor",
"Constellations"
] |
69,009,928 | https://en.wikipedia.org/wiki/Curium%28III%29%20bromide | Curium(III) bromide is the bromide salt of curium. It has an orthorhombic crystal structure.
Preparation
Curium bromide can be produced by reacting curium chloride and ammonium bromide in a hydrogen atmosphere at 400–450 °C.
It can also be produced by reacting curium(III) oxide and hydrobromic acid at 600 °C.
Properties
Curium bromide is an ionic compound composed of Cm3+ and Br−, appearing as a colorless solid. It is orthorhombic, with space group Cmcm (No. 63) and lattice parameters a = 405 pm, b = 1266 pm and c = 912 pm. Its crystal structure is isostructural with plutonium(III) bromide.
References
Curium compounds
bromides
Actinide halides | Curium(III) bromide | [
"Chemistry"
] | 170 | [
"Bromides",
"Salts"
] |
69,015,860 | https://en.wikipedia.org/wiki/Brendel%E2%80%93Bormann%20oscillator%20model | The Brendel–Bormann oscillator model is a mathematical formula for the frequency dependence of the complex-valued relative permittivity, sometimes referred to as the dielectric function. The model has been used to fit to the complex refractive index of materials with absorption lineshapes exhibiting non-Lorentzian broadening, such as metals and amorphous insulators, across broad spectral ranges, typically near-ultraviolet, visible, and infrared frequencies. The dispersion relation bears the names of R. Brendel and D. Bormann, who derived the model in 1992, despite first being applied to optical constants in the literature by Andrei M. Efimov and E. G. Makarova in 1983. Around that time, several other researchers also independently discovered the model. The Brendel-Bormann oscillator model is aphysical because it does not satisfy the Kramers–Kronig relations. The model is non-causal, due to a singularity at zero frequency, and non-Hermitian. These drawbacks inspired J. Orosco and C. F. M. Coimbra to develop a similar, causal oscillator model.
Mathematical formulation
The general form of an oscillator model is given by
where
is the relative permittivity,
is the value of the relative permittivity at infinite frequency,
is the angular frequency,
is the contribution from the th absorption mechanism oscillator.
The Brendel-Bormann oscillator is related to the Lorentzian oscillator and Gaussian oscillator , given by
where
is the Lorentzian strength of the th oscillator,
is the Lorentzian resonant frequency of the th oscillator,
is the Lorentzian broadening of the th oscillator,
is the Gaussian broadening of the th oscillator.
The Brendel-Bormann oscillator is obtained from the convolution of the two aforementioned oscillators in the manner of
,
which yields
where
is the Faddeeva function,
.
The square root in the definition of must be taken such that its imaginary component is positive. This is achieved by:
References
See also
Cauchy equation
Sellmeier equation
Forouhi–Bloomer model
Tauc–Lorentz model
Lorentz oscillator model
Condensed matter physics
Electric and magnetic fields in matter
Optics | Brendel–Bormann oscillator model | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 513 | [
"Applied and interdisciplinary physics",
"Optics",
"Phases of matter",
"Electric and magnetic fields in matter",
"Materials science",
"Condensed matter physics",
" molecular",
"Atomic",
"Matter",
" and optical physics"
] |
69,017,499 | https://en.wikipedia.org/wiki/Kathryn%20McGrath | Kathryn McGrath is a New Zealand chemical scientist. She is deputy vice-chancellor (research) at the University of Technology Sydney, Australia.
Biography
McGrath was educated at Burnside High School in Christchurch, and went on to study at the University of Canterbury, where she completed a BSc(Hons) degree in chemistry. She then earned a PhD at the Australian National University in Canberra. Her thesis focused on the properties of liquid crystals. After completing her doctoral studies, she held postdoctoral positions at Pierre and Marie Curie University in Paris, and Princeton University in the United States.
On returning to New Zealand, McGrath lectured in chemistry at the University of Otago in Dunedin, where she also completed a postgraduate diploma in finance. In 2004, she moved to Victoria University of Wellington where she lectured in the School of Chemical and Physical Sciences, and rose to the rank of full professor. She also held the position of vice-provost (research) and in 2011 was appointed director of the MacDiarmid Institute for Advanced Materials and Nanotechnology. In 2018, she moved to the University of Technology Sydney.
Recognition
McGrath was awarded the Easterfield Medal by the New Zealand Institute of Chemistry in 2003, and the Research Medal (now Hill Tinsley Medal) by the New Zealand Association of Scientists in 2007. In 2013, she received the Wellington City Council's Gold Inspire Wellington Award. McGrath is a Fellow of the New Zealand Institute of Chemistry.
References
Living people
People educated at Burnside High School
University of Canterbury alumni
University of Otago alumni
Academic staff of the University of Otago
Year of birth missing (living people)
Women physical chemists
Australian National University alumni
Academic staff of Victoria University of Wellington
Academic staff of the University of Technology Sydney
New Zealand chemists
Australian physical chemists
New Zealand women academics
Australian women academics
Fellows of the New Zealand Institute of Chemistry | Kathryn McGrath | [
"Chemistry"
] | 366 | [
"Women physical chemists",
"Physical chemists"
] |
69,017,930 | https://en.wikipedia.org/wiki/Conversations%20%28software%29 | Conversations is a free software, instant messaging client application software for Android. It is largely based on recognized open standards such as the Extensible Messaging and Presence Protocol (XMPP) and Transport Layer Security (TLS).
The development focus is on secure communication and implementation of XMPP extensions that are important for mobile use. The trade press praised the decentralized and open nature of the transmission network and simple, intuitive usability with user guidance familiar from other applications. It enjoys recognition as a serious attempt to raise the mass suitability of XMPP-based messaging to a competitive level.
The source code of the software is maintained at GitHub, and is subject to the terms of the GPL-3.0-only license. The application can be installed for free (or with donations) using F-Droid, or for a fee in the Google Play store. Google recorded over 100,000 installations as of November 2020.
Features
Conversations includes optional end-to-end encryption (OpenPGP or OMEMO), and in-transit encryption (Transport Layer Security). The latter must be configured by the server computers involved in the messaging.
Conversations allows users to have multiple client devices (endpoints) logged into an account simultaneously (through XMPP), and also delivers messages to multiple client devices (synchronization) using the protocol extension "Message Carbons" ("carbon copies", XEP-0280).
Files, also encrypted, can be sent between users. Transmitted images are displayed in the conversation view as inline image messages.
As an XMPP client, Conversations can exchange messages with other, different XMPP client software, in principle, and is also not tied to a particular vendor's server infrastructure. The following features are also included:
Multi-User (Group) chat (MUC)
Optional address book integration
Support for multiple user accounts or addresses
Implemented XMPP extension protocols
Conversations handles many XMPP extension protocols (XEP, official extensions of XMPP).
History
In the wake of the Edward Snowden disclosures in June 2013, and Facebook's buyout of WhatsApp in February 2014, "secure" messengers for mobile devices were gaining popularity. Initial Conversations source code was contributed to the public repository on January 24, 2014, and the first official version, 0.1, was released on March 24, 2014. Conversations soon received positive feedback.
Conversations was added to Google Play later in spring 2014, and to the alternative Android software repository F-Droid with version 0.1.3 on April 6, 2014.
Since version 0.2, released on May 12, image messages (file transfers, in plain text or OpenPGP-encrypted) are supported, from version 0.4 (June 30) also OTR-encrypted. Version 1.0 followed on February 1, 2015.
Developer Andreas Straub participated in the Google Summer of Code for Conversations in 2015. This produced drafts of a new end-to-end encryption standard (OMEMO), which were submitted to the XMPP Standards Foundation (XSF) for standardization.
As of version 2.0.0, the ability to use Off-the-Record Messaging (OTR) for encryption has been removed. Furthermore, OMEMO is now enabled by default in individual chats and private group chats. Version 2.2.0 implemented previously optional extensions to record voice messages and share location in Conversations in May 2018.
Version 2.3.0 introduced support for TLS 1.3 in September 2018.
Version 2.8 introduced encrypted audio and video calls in April 2020.
Quicksy
The offshoot instant messenger, Quicksy, was also created by Daniel Gultsch. Users of this client open an account at the host quicksy.im, where the username consists of the phone number. This enables a contact search for other users of the app using the contacts list or phone book. This is intended to lower the barrier to entry into the XMPP (Jabber) network. Quicksy users can also communicate with XMPP users on other hosts.
In 2024, the Monal team, who edits the xmpp application for iOS, adapts it's software (Monal) to use mobile-based identification, and uses the Quicksy name, to make it available on iOS, with the agreement of Quicksy's author.
Reception
The Free Software Foundation includes Conversations in their software directory.
In an analysis of Conversations and Xabber apps, researchers found that "forensic artefacts" could be found on an Android device including local user, contacts and body of messages sent or received using the app, as plaintext in the main database maintained by the app.
In 2017, Raul Radonz of XDA Developers wrote a detailed review of Conversations, including an interview of developer Daniel Gultsch. The review highlighted choices of encryption and inclusion of "Forward Secrecy".
In a 2020 review, Decentralize Today said "XMPP and Conversations has the potential to be an excellent and super secure messenger if you host it yourself," but "problems could emerge when you use XMPP with contacts who are on different servers."
Anticapitalist webhost company, Autistici, wrote detailed setup instructions for Conversations for their XMPP service.
Notable usages
In 2018, german police moves from Whatsapp application to Moka, a fork of Conversations, for all it's employees.
See also
Comparison of instant messaging clients
Comparison of instant messaging protocols
Secure communication
SIMPLE
References
External links
Source code on GitHub
Conversations on PRISM Break
Instant messaging
Android (operating system) software
Free XMPP clients
XMPP clients | Conversations (software) | [
"Technology"
] | 1,178 | [
"Instant messaging"
] |
69,018,026 | https://en.wikipedia.org/wiki/2021%20Kaohsiung%20building%20fire | In the early morning hours of 14 October 2021, at , a fire broke out in a 13-storey building at Fubei Road in Yancheng District, Kaohsiung, a city in southwestern Taiwan. At least 46 people were killed, and 41 others were injured. The fire was extinguished after about four and a half hours. The cause of the fire is under investigation, although piles of debris left around the building may have complicated rescue efforts and helped fuel the fire.
It was the deadliest fire in the city's history, and the deadliest building fire in Taiwan since 1995, when a karaoke bar in Taichung in central Taiwan caught fire, killing 64 people and overall the third-deadliest fire in the history of Taiwan.
Background
The Cheng Chung Cheng Building (), built around 1981, is a 13-floor commercial and residential building, one of many apartment buildings in the Yancheng District, an older section of Kaohsiung. The mayor of Kaohsiung Chen Chi-mai stated that the building had previously housed a cinema, as well as restaurants and karaoke lounges, but was partially abandoned at the time of the fire, save for around 120 households. Officials also stated that the building was 40 years old, and that a few shops were located in the lower levels. Two underground floors were not being used, and the first to fifth floors were abandoned.
About 120 households lived between the seventh and eleventh floors. Fire chief Lee Ching-hsiu stated that most of the residents were elderly and either suffering from physical ailments or dementia. The apartments were as small as , and many residents lived alone.
The tower had suffered another fire earlier in its lifetime, in 1999. This earlier fire had occurred during daylight hours, and firefighters were able to rescue 28 people that were trapped in the building, resulting in no deaths.
Locals called the tower "Kaohsiung's No. 1 ghost building". Fire extinguishers had only been installed the month prior, with only three per floor due to lack of funds. In 2007, Apple Daily reported that the abandoned theatre in the building had become a meeting spot for gay men to engage in sexual activities. Urban explorers visiting in 2014 wrote that several sewer pipes in the building's upper floor had burst and that the lower floors were occupied by squatters.
Fire
The city's fire department stated that the fire was first reported at . It is believed by authorities that the fire first broke out, reportedly at 02:45, at a tea-shop on the ground floor of the building. A survivor said she opened her door and saw black smoke everywhere, and other residents stated they heard a loud bang concurrent with that of an explosion before the fire was discovered.
Some 159 firefighters responded to the fire with 75 fire vehicles. Chief Lee stated that because the lower floors had high ceilings and a front made of glass, the fire rose up rapidly, eventually reaching up to the 6th floor, and filling the floors above with smoke. By midday at least 62 people had been evacuated from the building, aged between 8 and 83 years-old. Lee reported that the fire had been extinguished by 07:17NST. More than 377 rescue workers were deployed to the scene and the rescue is ongoing.
While the cause of the fire was not reported immediately, the large amount of debris and clutter in the building reportedly helped spread the fire and added to its intensity. The debris and clutter also impeded the search and rescue and evacuation efforts as many points of access were blocked. Hours after the fire, smoke could still be seen, and the sound of glass breaking was heard around the building.
Casualties
A total of 46 people died and a further 41 were injured. The fire bureau noted that the average age of the deceased was 62.
Initially, only seven people were reported dead by authorities, but the number grew throughout the night. Thirty-two people were declared deceased at the scene of the fire and sent directly to the morgue, while an additional 14 were sent to the hospital with no signs of life and declared dead there.
According to Chief Lee, the number of casualties was expected to rise, as some victims were still believed to be trapped between the 7th and 11th floors. Lee also noted that most of the casualties were caused by smoke inhalation and added that one reason why the casualty count was so high was because the fire happened during the early morning hours, while people were still asleep.
Three of the people who had died were Mainland Chinese citizens formerly married to Taiwanese nationals.
Investigation
Authorities have also ordered an investigation to determine the cause of the fire, and have not ruled out the possibility of arson. The police have summoned four witnesses for the investigation. A man surnamed Kuo and a woman surnamed Huang were detained by the Kaohsiung District Prosecutors' Office. After questioning, Kuo was granted bail.
Aftermath
President Tsai Ing-wen asked authorities to help relocate those affected. Kaohsiung city councilors called for fire safety to be improved throughout the city, including investigations of old buildings, amending safety standards, and equipment and infrastructure upgrades. Tsai visited the site of the fire on 16 October 2021, and pledged that her administration would improve fire safety and aid urban renewal.
Kaohsiung mayor Chen Chi-mai stated that the city government would pay medical fees for the injured, and aid the people that the fire forced to move. The Taipei City Government subsequently announced that new fire safety laws were to go into effect in January 2022, while members of the Taichung City Council pushed for a report to be made on the city's older structures, and Tainan mayor Huang Wei-cher ordered inspections of fifty buildings.
On 15 October 2021, a Taoist prayer was held at the site of the fire, and that day's Legislative Yuan session opened with a moment of silence.
Kaohsiung mayor Chen Chi-mai accepted the resignation of Fire Bureau chief Lee Ching-hsiu and Public Works Bureau Director-General Su Chih-hsun on 26 October 2021.
Demolition
In November 2021, a team of civil engineers and architects inspected the burnt-out building, and determined it was no longer structurally sound, and its interior conditions were a threat to public safety. They recommended that the building be demolished. The city government proposed replacing the demolished building with a public park and memorial. The building had a complex ownership structure, with property rights divided amongst hundreds of shareholders, a few of whom initially opposed the demolition. But the city government bought out their shares at above-market rates, allowing demolition to proceed on 17 December 2021. Former residents had been given notice that all recoverable belongings must be moved out of the building before then.
As of February 2022, the roof deck and 12th floor (formerly an abandoned restaurant) have been demolished. The demolition was briefly suspended after nearby residents complained about excessive noise and air pollution.
As of May 2022, demolition is almost complete, and the site is expected to be cleared of all debris by end of month. The park is scheduled to be constructed by September 2022.
As of November 2023, a fully functional park, complete with children’s recreation area exists on site.
See also
2015 Baku residence building fire
Grenfell Tower fire
FR Tower fire
List of building or structure fires
References
2021 fires in Asia
2021 in Taiwan
21st century in Kaohsiung
Industrial fires and explosions
Commercial building fires
Explosions in 2021
Fires in Taiwan
October 2021 events in Asia
Residential building fires in Asia
Urban fires in Asia
High-rise fires
2021 disasters in Taiwan
Explosions in Taiwan | 2021 Kaohsiung building fire | [
"Chemistry"
] | 1,534 | [
"Industrial fires and explosions",
"Explosions"
] |
69,018,329 | https://en.wikipedia.org/wiki/Cladostephaceae | Cladostephaceae is a family of brown algae belonging to the order Sphacelariales in the class Phaeophyceae.
The family comprises a single genus:
Cladostephus C.Agardh, 1817
References
Brown algae
Brown algae families | Cladostephaceae | [
"Biology"
] | 55 | [
"Algae",
"Brown algae"
] |
69,019,121 | https://en.wikipedia.org/wiki/Meyers%E2%80%93Serrin%20theorem | In functional analysis the Meyers–Serrin theorem, named after James Serrin and Norman George Meyers, states that smooth functions are dense in the Sobolev space
for arbitrary domains . A domain is any open, non-empty subset of .
Historical relevance
Originally there were two spaces: defined as the set of all functions which have weak derivatives of order up to k all of which are in and defined as the closure of the smooth functions with respect to the corresponding Sobolev norm (obtained by summing over the norms of the functions and all derivatives). The theorem establishes the equivalence of both definitions. It is quite surprising that, in contradistinction to many other density theorems, this result does not require any smoothness of the domain . According to the standard reference on Sobolev spaces by Adams and Fournier (p 60): "This result, published in 1964 by Meyers and Serrin ended much confusion about the relationship of these spaces that existed in the literature before that time. It is surprising that this elementary result remained undiscovered for so long."
References
.
.
Sobolev spaces
Theorems in functional analysis | Meyers–Serrin theorem | [
"Mathematics"
] | 234 | [
"Theorems in mathematical analysis",
"Mathematical analysis",
"Theorems in functional analysis",
"Mathematical analysis stubs"
] |
69,021,575 | https://en.wikipedia.org/wiki/Dorrit%20Jacob | Dorrit E. Jacob is a German-born Australian geochemist. She is the first woman to serve as Director of the Research School of Earth Sciences at the Australian National University (ANU) where she is a full professor.
Jacob completed her undergraduate studies in mineralogy and geology at the University of Mainz, Germany. She moved to the Georg-August University in University of Göttingen from which she received a Dr. rer. nat., while her PhD thesis work was performed at the Max-Planck Institute for Chemistry.
Jacob was awarded the Heisenberg Chair in Biomineralisation at the University of Mainz in 2012. In 2013 Jacob moved to Australia where she took up an ARC future fellowship at Macquarie University to study the formation of bivalve shells and pearls and how they are used to reconstruct past records of climate change.
Her areas of research include biomineralisation, and diamond formation. On that last point, Jacob and other researchers closely examined minuscule “melts” enveloped within a diamond and found oxidation of sulfide mineral pyrrhotite can trigger the gem’s growth.
As of 2020 she leads the Biominerals as Environment Archives project at the ANU, where she also is a full Professor.
In May 2021 Jacob was elected a Fellow of the Australian Academy of Science.
Publications
Redox-freezing and nucleation of diamond via magnetite formation in the Earth’s mantle, 2016
Element substitution by living organisms: the case of manganese in mollusc shell aragonite, 2016
Planktic foraminifera form their shells via metastable carbonate phases, 2017
The mesoscale order of nacreous pearls, 2021
References
External links
ANU profile of Professor Dorrit Jacob
Living people
Year of birth missing (living people)
Johannes Gutenberg University Mainz alumni
University of Göttingen alumni
Academic staff of Macquarie University
Academic staff of the Australian National University
Australian geochemists | Dorrit Jacob | [
"Chemistry"
] | 390 | [
"Geochemists",
"Australian geochemists"
] |
69,023,589 | https://en.wikipedia.org/wiki/List%20of%20Internet%20challenges | This is a list of Internet challenges.
Charity
Book Bucket Challenge – It went viral on social media during August–September 2014. The original Ice Bucket Challenge involved participants pouring a bucket of ice over their head or donating money to the ALS Association. The Book Bucket Challenge involves people sharing the names of 10 books that inspired them on their social networking pages or donating books to the needy and sharing those photos with friends on social networking sites.
Food Stamp or SNAP Challenge – a trend in the United States popularized by religious groups, community activists and food pantries, in which a family of means chooses to purchase food using only the monetary equivalent of what a family that size would receive in the US federal government Supplemental Nutrition Assistance Program (SNAP), colloquially called food stamps. In 2015, this amounted to US$194.00 per person per month, or nearly $7.00 per day.
Ice Bucket Challenge – A charity-driven effort where a person "tags" three other people over social media, challenging them either to donate $100 to the ALS Association, or to otherwise douse themselves with a bucket of ice-cold water while filming themselves as well as making a smaller donation and tagging three others with the same challenge. As the challenge propagated, it tagged various celebrities and people with large numbers of social followers, causing the challenge to grow in a viral manner.
Trashtag Challenge – An environmental challenge encouraging people to clean-up litter and post before/after photos. The challenge went viral in 2019 and is part of a movement to clean up litter and trash from the outdoors. Organizations that are actively involved in the challenge include National CleanUp Day, Earth Day, Keep America Beautiful, and World Cleanup Day.
Crime
Devious lick – a trend, popular among teenagers, that involves stealing object(s) from school, such as soap, sanitizers and toilet paper
Gallon smashing – A challenge which surfaced on YouTube in 2013, originally invented by Zayd, Faysal, and Omar Khatib for TheChaizyChannel, gallon smashing involves obtaining bottles of liquid in a supermarket (usually cow's milk or water) and then throwing them against the floor and spilling their contents in such a way that the act is seen to be accidental rather than deliberate. The participant may attempt to damage other objects as they throw the bottles or fall into the resultant spill and seek the assistance of customers to help them up. Participants of this challenge often sustain injuries and frequently face punishment from legal authorities, including the three teenagers who originally started the phenomenon.
Happy slapping – a fad in parts of Europe around 2005, mostly in the UK and France, where people randomly attacked others in public and had themselves filmed. Multiple people were killed as a result of these incidents. An "anti happy-slapping" law enacted as a response to the fad in France resulted in a debate about censorship.
Penny Outlet Challenge – A year after YouTube announced its ban on extremely dangerous challenges videos, users migrated to TikTok to share their videos of the new viral challenge. A participant plugs a phone charger partly into an outlet, then touches a penny to the exposed prongs between the phone charger and the electrical socket, causing sparks and electrical damage and potentially starting a fire on the connected circuit. The Massachusetts State Fire Marshal issued a letter warning fire departments and schools regarding the challenge after three independent incidents in Massachusetts, two of which reportedly resulted in criminal charges. In December 2021, Amazon Alexa suggested the challenge to a 10-year-old. Alexa had reportedly taken the Penny Challenge from an online resource that specifically warned that the challenge was dangerous. Amazon later stated the problem had been fixed.
Skullbreaker challenge – A TikTok challenge that went viral in February 2020 and spread to other sections of the internet. The challenge involves two people convincing another person to jump, and then kick their legs out, causing the person jumping to fall on their head. Several people have been hospitalized after performing this challenge.
"Trash Bucket Challenge" aka "peoples' lustration" – video coverage of illegal acts of extrajudical throwing of allegedly corrupt politicians into trash dumpsters committed by far-right radicals.
Food and drink
Banana Sprite Challenge – a challenge to quickly eat two bananas and drink one can of Sprite without vomiting. There are other versions of the challenge, but the suggested premise is that the body cannot digest both substances at the same time. While the vomit response is commonly assumed to be a chemical reaction between the two foods, the reaction may also occur due simply to the large amount of food and drink ingested within a short period. Dietitian Heather Boline observes that the human stomach can only hold around two cups, saying "Too much food or liquid in your stomach if your stomach doesn't have that capability can make you vomit." Thus, the vomiting response is likely due to the volume of food and drink being higher than the volume of the stomach.
Cheesed Challenge – A Twitter trend. Parents film themselves tossing cheese slices at their babies.
Cinnamon challenge – A viral Internet food challenge. The objective of the challenge is to film oneself swallowing a spoonful of ground cinnamon in under 60 seconds without drinking anything, then upload the video to the Internet. The challenge is difficult and carries substantial health risks because the cinnamon coats and dries the mouth and throat, resulting in coughing, gagging, vomiting, and inhaling of cinnamon, leading to throat irritation, breathing difficulties, and risk of pneumonia or a collapsed lung.
Grimace Shake – a milkshake made by McDonald's to celebrate an old mascot, Grimace, his birthday. Social media users would make a video, prominently on TikTok, and wish Grimace a Happy Birthday, drink it, and give a brief review. During the review, the videos would cut to a dark scene with the milkshake spilled on ground and on body, users playing dead (sometimes coughing up the shake or becoming zombies) and scary music.
One Chip Challenge — A challenge that started in 2016, and formerly promoted by Paqui, a tortilla chip brand owned by The Hershey Company. Participants must eat one Paqui Carolina Reaper chip, sold individually, and avoid eating or drinking anything afterwards. After a 14-year-old boy died on the same day that he attempted the challenge, Paqui withdrew the super-spicy chips from sale and offered refunds to customers.
Salt Chip Challenge - This is similar to the One Chip Challenge, but involves excessive salt instead of excessive heat.
Health
Coronavirus Challenge – the challenge involves licking various surfaces such as door handles and even public toilet bowls. At least one person who took the challenge was reported to have contracted COVID-19.
I Will Survive coronavirus challenge – Named after Gloria Gaynor's hit song, the aim is to encourage people to properly wash their hands in light of the coronavirus pandemic. The iconic singer made a video that has since gone viral on TikTok.
Music
Everywhere at the End of Time – A challenge in which people listen to this six-hour album set from Leyland James Kirby, a sonic depiction of dementia that features early 20th-century recordings (most prominently the 1931 song "Heartaches") slowly become more degraded and jumbled until it devolves into noise in line with a dementia patient's memory and cognitive function. It emerged as an Internet challenge in 2020. Kirby was strongly in favor of the challenge as a way to raise awareness of dementia.
Mannequin Challenge – a viral Internet video trend that started in October 2016 where people remain still while a video is recorded, usually with music in the background, most commonly "Black Beatles" by Rae Sremmurd. It became especially popular with sports teams and athletes.
Running Man Challenge – A series of dance videos originally created by Hillside, New Jersey high school students Kevin Vincent and Jeremiah Hall on Instagram that uses the song "My Boo" by Ghost Town DJ's.
Sailor Moon redraw challenge – in this challenge artists redraw a screenshot of Sailor Moon, the character from the series of the same name, in their own art styles. Alternatively, the scene is redrawn with another fictional character taking her place.
Stunts
Bird Box Challenge – For its film Bird Box, where a significant plot element has characters keeping themselves blindfolded to prevent insanity, Netflix partnered with Twitch streamers to challenge them to play video games blindfolded. However, the challenge morphed into people attempting everyday activities fully blindfolded while being recorded, which included attempting to cook, walk in busy streets, and drive cars. Several of these videos have gone viral, but others repeating the challenges have gotten themselves into a number of non-fatal injuries. Netflix and law officials have issued warnings that people should only perform Bird Box challenges in safe, isolated places to eliminate the potential to injure themselves and others.
Bottle Cap Challenge – A martial arts challenge where one must kick the bottle cap off without knocking over the bottle itself.
Condom challenge – A viral Internet challenge. The challenge involves inserting a latex condom into the nostril and snorting it into the nasal cavity and back through the throat to be coughed out of the mouth. The term "condom challenge" was coined in May 2012 following the widespread popularity of the cinnamon challenge, but the idea is several years old and videos of challenge attempts date to at least 2007. The challenge went viral in April 2013, when WorldStarHipHop posted a video of two young women attempting the challenge, and several people subsequently uploaded videos onto the Internet of themselves attempting the challenge. The stunt poses potential choking hazards.
Milk crate challenge - involves stacking milk crates and climbing the resulting structure, which is usually unstable and the resulting fall is likely to cause injuries.
Planking - An internet phenomenon which emerged in 2011, which involved lying face down in peculiar and humorous locations. In 2011, a 20-year-old man from Brisbane, Australia fell to his death after planking on a seven-story building.
Salt and ice challenge – Internet phenomenon wherein participants pour salt on their bodies, usually on the arm and ice is then placed on the salt. This causes a "burning" sensation, and participants are challenged to withstand the pain for as long as they can. The challenge is recorded and posted on YouTube or other forms of social media. This challenge has caused many burns as a result.
Yoga Challenge – A continuing YouTube video trend that first went viral during the summer of 2014 involving participants who attempt to perform a series of acroyoga poses that are taken from the internet. Typically, participants are not trained in yoga, which results in humorous outcomes (awkward stances, falling down, etc.). These attempts are captured on film, usually on a smartphone or tablet camera, and uploaded to YouTube. Usually, prior to attempting a pose, participants will show an image of the pose they are attempting. The contrast between correct poses by professionals and incorrect poses by amateurs adds to the humor. YouTuber Alfie Deyes posted a video titled The Yoga Challenge! in June 2014 which may have set off the trend. Deyes' video may have been inspired by various popular "couples' stunts" and "yoga fail" videos by channels such as BFvsGF posted as early as 2012. BFvsGF reattempted the trend by posting a video titled "Acro Yoga Challenge" in July 2014. The "challenge" part may stem from the "30-Day yoga challenge" that was a popular fitness vlogging trend on YouTube as early as the mid-2000s.
Others
Benadryl Challenge – A challenge involving taking dangerous amounts of Benadryl, to achieve a high, and experience hallucinations. Several teenagers had been hospitalized as a result of participating in the challenge, and one teenager from Oklahoma had reportedly died.
Blackout Challenge/Choking Game – A challenge involving deliberately tying belts, cords, and other ligatures around ones neck, for the purpose of experiencing a "high". While the blackout challenge did not originate on the Internet, it had resurfaced in popularity on TikTok during the COVID-19 pandemic. Several participants, mainly children and teenagers, had been hospitalized, and seven children had reportedly died.
Cameron Boyce Challenge – After Cameron Boyce died at age 20, a new challenge began to trend as people mimicked the symptoms of epileptic seizure that led to his death. Fans called out this challenge as obscene, considering it an insult to his immediate family and to everyone with epilepsy.
Charlie Charlie Challenge – A ouija-emulating ritual in which the spirit of a Mexican demon named "Charlie" is invoked via two pencils in the shape of a cross and the words "yes" and "no" written on paper in a square. Social media users began circulating videos of pencils moving to the word "yes" when asking if the demon is present.
Deodorant challenge – involves either spraying deodorant onto the bare skin, often causing aerosol burns, or directly inhaling deodorant, trying to achieve a high. This can cause a variety of symptoms, most notably asphyxia.
Eraser Challenge – a trend popular among school children where one rubs an eraser on their bare skin as hard as they can while reciting the English alphabet. This forceful rubbing action can cause friction burns and scars to the skin if prolonged, and put the affected area at risk of infection, thus leading to parental concerns.
Fire challenge – an activity which refers to the application of flammable liquids to one's body and then setting the liquids aflame, while being video recorded. The aftermath is then posted to social media sites. Firefighters, police officers and media sources have chastised and spoken out against the activity, hoping to dissuade individuals from trying it due to its harmful nature. In 2021, a TikTok variant of this challenge involves drawing shapes on the bare skin using any flammable substance (typically alcohol) and lighting it on fire, resulting in similar consequences to the original.
Kylie Jenner Lip Challenge – Based on trying to recreate the full lips of television star Kylie Jenner, Internet users show themselves using a small vessel like a shot glass that covers their lips, drawing all the air out of the vessel, and then releasing, which temporarily puffs the lips by drawing the user's blood into them. The activity is considered harmful, both from bruising and dis-figuration of the lips, and the potential for the vessel to shatter and cut the person.
No Nut November is an internet challenge revolving around abstinence, in which participants abstain from masturbation and ejaculation, or colloquially "to nut", during the month of November. It originated in the early 2010s and grew in popularity on social media during and after 2017.
Orbeez Challenge – Involves shooting people with gel blasters using water beads such as Orbeez. Some of uses of the phrase "Orbeez Challenge" only involve playing with the beads, not shooting.
Tide Pod Challenge – Similar to other eating challenges, this saw people attempt to eat Tide Pods, small packets filled with laundry detergent and other chemicals that normally dissolve while in a washing machine. The challenge gained attention in late 2017 and early 2018, and quickly was addressed by several health-related organizations, as the chemicals in the packet are poisonous and toxic to humans. These agencies sought to warn users and strongly discourage the challenge after dozens of cases of poisoning were reported within the first few weeks of 2018, while YouTube took action to remove videos related to the challenge to further stop its spread.
Vacuum Challenge – A challenge which emerged in 2019, where parents would have their children sit in a garbage bag with their knees against their chest, and vacuum seal the bag, giving the appearance of a skin tight latex bodysuit. The challenge poses a possible asphyxiation hazard, as well as possible bodily harm caused by an airtight bag.
References
History of the Internet
Internet-related lists | List of Internet challenges | [
"Technology"
] | 3,246 | [
"Computing-related lists",
"Internet-related lists"
] |
69,023,655 | https://en.wikipedia.org/wiki/Urban%20flooding | Urban flooding is the inundation of land or property in cities or other built environment, caused by rainfall or coastal storm surges overwhelming the capacity of drainage systems, such as storm sewers. Urban flooding can occur regardless of whether or not affected communities are located within designated floodplains or near any body of water. It is triggered for example by an overflow of rivers and lakes, flash flooding or snowmelt. During the flood, stormwater or water released from damaged water mains may accumulate on property and in public rights-of-way. It can seep through building walls and floors, or backup into buildings through sewer pipes, cellars, toilets and sinks.
There are several types of urban flooding, each with a different cause. City planners distinguish pluvial flooding (flooding caused by heavy rain), fluvial flooding (caused by a nearby river overflowing its banks), or coastal flooding (often caused by storm surges). Urban flooding is a hazard to both the population and infrastructure. Some well known disaster events include the inundations of Nîmes (France) in 1998 and Vaison-la-Romaine (France) in 1992, the flooding of New Orleans (United States) in 2005, and the flooding in Rockhampton, Bundaberg, Brisbane during the 2010–2011 Queensland floods in Australia, the 2022 eastern Australia floods, and more recently the 2024 Rio Grande do Sul floods in Brazil.
In urban areas, flood effects can be made worse by existing paved streets and roads which increase the speed of flowing water. Impervious surfaces prevent rainfall from infiltrating into the ground, thereby causing a higher surface run-off that may by higher than the local drainage capacity. The effects of climate change on the water cycle can also change the severity and frequency of urban flooding. This applies in particular to coastal cities which may be affected by sea level rise and higher rainfall intensity.
To reduce urban flooding, city planers can use for example the following approaches: building gray infrastructure, using green infrastructure, improving drainage systems, and understanding and altering land use. In general terms, integrated urban water management can help with reducing urban floods.
Causes
There are several types of urban flooding, each with a different cause:
Pluvial (flooding caused by heavy rain),
Fluvial (caused by a nearby river overflowing its banks), and
Coastal flooding (often caused by storm surges).
Different types of urban flooding create different impacts and require different mitigation strategies.
Any activities that enlarge the impermeable surface areas in a city can increase the flood risk. Impermeable surface areas are generated through soil sealing as this reduces drainage options of floodwaters. As the pace of urbanization accelerates around the world, urban flooding has the potential to affect more people.
Some researchers have mentioned the storage effect in urban areas with transportation corridors created by cut and fill. Culverted fills may be converted to impoundments if the culverts become blocked by debris, and flow may be diverted along streets. Several studies have looked into the flow patterns and redistribution in streets during storm events and the implication on flood modelling.
Links to climate change
Many of the common causes of urban flooding, including storm surges, heavy precipitation, and river overflow, are expected to increase in frequency and severity as climate change intensifies and causes increases in ocean and river levels. In particular, erratic rainfall patterns are expected to increase the frequency and severity of both pluvial flooding (as excessive amounts of rainfall in urban areas and cannot be adequately absorbed by existing drainage systems and pervious areas) and fluvial flooding (as excessive rainfall over a river can cause flooding and overflow, either where it occurs or downstream along the path of the river). The severity of extreme storm events, including hurricanes and other types of tropical cyclones, are also expected to increase. Additionally, due to the geographic distribution of developing urban areas, the land area potentially exposed to climate change-related flooding is expected to increase significantly.
Coastal cities may be particularly affected by sea level rise and higher rainfall intensity.
Impacts
Some of the most obvious impacts of urban flooding are those to human life and to property damage. In 2020, floods caused an estimated 6,000 deaths and caused US$51.3B in damages globally. Residents at low-elevated regions are often at risk of inundation, financial loss, and even the loss of lives.
Urban flooding also impacts critical public services, including public transportation systems. Traffic congestion can be worsened by urban flood events.
Economic impacts
The IPCC summarized the current research regarding economic impacts as follows (as of 2022): "economic risks associated with future surface water flooding in towns and cities are considerable." This is explained as part of the dynamic Interaction of urban systems with climate.
Urban flooding has significant economic implications. In the US, industry experts estimate that wet basements can lower property values by 10%-25% and are cited among the top reasons for not purchasing a home. According to the U.S Federal Emergency Management Agency (FEMA), almost 40% of small businesses never reopen their doors following a flooding disaster. In the UK, urban flooding is estimated to cost £270 million a year in England and Wales; 80,000 homes are at risk.
A study of Cook County, Illinois, identified 177,000 property damage insurance claims made across 96% of the county's ZIP codes over a five-year period from 2007 to 2011. This is the equivalent of one in six properties in the County making a claim. Average payouts per claim were $3,733 across all types of claims, with total claims amounting to $660 million over the five years examined.
Urban flooding can also create far-reaching supply chain issues, which can create significant interruptions in the availability of goods and services, as well as financial losses for businesses.
Between 1961 and 2020, nearly 10,000 cases were reported with 1.3 million deaths and a minimum of US$3.3 trillion of financial losses at an equivalent loss rate of almost US$1800 per second. On average, the total reported deaths worldwide were around 23,000/year for the past 6 decades at an equivalent rate of one death every 24 min.
Modeling
Localized models
Flood modeling is often conducted in a very localized fashion, with hydrological models created for individual municipalities and incorporating details about buildings, infrastructure, vegetation, land use, and drainage systems. This localized modeling can be very useful, especially when paired with historical data, in predicting which specific locations (e.g. streets or intersections) will be the most impacted during a flood event and can be helpful in designing effective mitigation systems specific to local needs.
Flood flows in urban environments have been investigated relatively recently despite many centuries of flood events. Some researchers mentioned the storage effect in urban areas. Several studies looked into the flow patterns and redistribution in streets during storm events and the implication in terms of flood modelling. Some recent research considered the criteria for safe evacuation of individuals in flooded areas. But some recent field measurements during the 2010–2011 Queensland floods showed that any criterion solely based upon the flow velocity, water depth or specific momentum cannot account for the hazards caused by the velocity and water depth fluctuations. These considerations ignore further the risks associated with large debris entrained by the flow motion.
The curve number (CN) rainfall–runoff model is widely adopted. However, it had been reported to repeatedly fail in consistently predicting runoff results worldwide. Unlike the existing antecedent moisture condition concept, one of the recent studies preserved the parsimonious curve number runoff predictive basic framework for model calibration according to different watershed's saturation conditions under guidance from inferential statistics. The study also showed that the existing CN runoff predictive model was not statistically significant without recalibration. CN runoff predictive model can be calibrated according to regional rainfall-runoff dataset for urban flash flood prediction.
Modeling of climate change impacts
Modeling of climate change impacts, on the other hand, is often done from a "top-down", global perspective. While these models can be helpful in predicting worldwide effects of global warming and in raising awareness about large-scale impacts, their spatial resolution is often limited to 25 km or more, making them less helpful for local planners in mitigating the effects of climate change on a street-by-street scale.
Some advocate for an integration of localized hydrological modeling with larger-scale climate modeling, claiming that such integration allows the benefits of both forms of modeling to be realized simultaneously and creates the potential for modeling flooding due to climate change in a way that allows planners to design specific strategies to mitigate it at the local level.
Scientists investigate climate change scenarios and their impacts on urban flooding and found that: "For example in the UK, expected annual damages from surface water may increase by £60–200 million for projected 2–4°C warming scenarios; enhanced adaptation actions could manage flooding up to a 2°C scenario but will be insufficient beyond that.
Mitigation and management
Flood flows in urban environments have been studied relatively recently despite many centuries of flood events. Some recent research has considered the criteria for safe evacuation of individuals in flooded areas.
Building gray infrastructure
One traditional urban flooding management strategy is building gray infrastructure, which is a set of infrastructure types (including dams and seawalls) traditionally constructed of concrete or other impervious materials and designed to prevent the flow of water. While gray infrastructure can be effective in preventing flooding-related damage and can be economically valuable, some models suggest that gray infrastructure may become less effective at preventing flood-related impacts in urban areas in the future as climate change causes flooding intensity and frequency to increase.
Using green infrastructure
An alternative to gray infrastructure is green infrastructure, which refers to a set of strategies for absorbing and storing stormwater at or close to the location where it falls. Green infrastructure includes many types of vegetation, large open areas with pervious surfaces, and even rainwater collection devices. Green infrastructure may prove to be an effective and cost-efficient way to reduce the extent of urban flooding.
Improving drainage systems
One way urban flooding is commonly mitigated is via urban drainage systems, which transport storm water away from streets and businesses and into appropriate storage and drainage areas. While urban drainage systems help municipalities manage flooding and can be scaled up as population and urban extent increase, these systems may not be sufficient to mitigate additional future flooding due to climate change.
Understanding and altering land use
Since the ratio of pervious to impervious surfaces across an area is important in flooding management, understanding and altering land use and the proportion of land allocated to different purposes/use types is important in flood management planning. In particular, increasing the percent of land dedicated to open, vegetated space can be helpful in providing an absorption and storage area for storm runoff. These areas can often be integrated with existing urban amenities, such as parks and golf courses. Increasing the pervious surface fraction of an urban area (e.g. by planting green walls/roofs or using alternative pervious construction materials) can also help de-risk climate-linked flood events.
Integrated urban water management
Examples
By country or region
Worldwide: List of floods
Africa: Floods in Africa
Australia: Floods in Australia
The Netherlands: Floods in the Netherlands
United States: Lists of floods in the United States
North Sea: Storm tides of the North Sea
United States
One of the most well known at-risk urban areas in the United States is New Orleans. Because of its coastal location and low elevation, the city is prone to flooding due to tropical storms, including cyclones and hurricanes and is particularly vulnerable to changes in sea level or storm frequency. In 2005, Hurricane Katrina caused more than 1800 deaths and US$170B in damages. After Katrina, additional flood protections were built with a changing climate in mind; these protections have proved effective in reducing damages due to subsequent extreme weather events, such as Hurricane Ida.
During the summer of 2021, Hurricanes Henri and Ida caused significant flooding in many cities along the east coast of the United States. In particular, New York City experienced record levels of rainfall, prompting many to question whether the city should implement additional flood protection measures in anticipation of potential future flood events. In September 2021, the New York City mayoral office released a new rainfall preparedness plan.
See also
Climate change adaptation#Flooding
References
Flood control
Stormwater management
Drainage | Urban flooding | [
"Chemistry",
"Engineering",
"Environmental_science"
] | 2,516 | [
"Water treatment",
"Stormwater management",
"Water pollution",
"Flood control",
"Environmental engineering"
] |
69,023,656 | https://en.wikipedia.org/wiki/Biopiracy | Biopiracy (also known as scientific colonialism ) is the unauthorized appropriation of knowledge and genetic resources of farming and indigenous communities by individuals or institutions seeking exclusive monopoly control through patents or intellectual property. While bioprospecting is the act of exploring natural resources for undiscovered chemical compounds with medicinal or anti-microbial properties, commercial success from bioprospecting leads to the company's attempt at protecting their intellectual property rights on indigenous medicinal plants, seeds, genetic resources, and traditional medicines.
Moreover, if biological resources and traditional knowledge are taken from indigenous or marginalized groups, the commercialization of their natural resource can harm communities. Despite the medicinal and innovative benefits of bioprospecting and biochemical research, the expropriation of indigenous land for their genetic resources without fair compensation inevitably leads to exploitation. Biopiracy can harm indigenous populations in multiple ways. Without proper compensation or reward for traditional knowledge of natural resources, the sudden increase in commercial value of the species producing the active compound can make it now unaffordable for the native people. In some cases, a patent filed by the western company could prohibit the use or sale of the resource by any individual or institution, including the indigenous group. With nearly one third of all small-molecule drugs approved by the U.S. Food and Drug Administration (FDA) between 1981 and 2014 being either natural products or compounds derived from natural products, bioprospecting or piracy is growing more significantly, especially in the pharmaceutical industry. Furthermore, the United Nations Educational, Scientific and Cultural Organization (UNESCO) mentions, in the context of intangible cultural heritage (ICH), that the medicinal traditions and knowledge of the Kallawaya communities in Peru have been affected by the lack of legal protection from pharmaceutical companies. A number of research projects are currently being developed on this subject, such as the research carried out using digital methods on the biopiracy of traditional medicines, which shows the current context of the problem by developing a description and analysis of the data, and by visualising and mapping the various organisations and actors in the social networks.
With the advancement of extraction techniques of genetic material in biochemistry and molecular biology, scientists are now able to identify a specific gene, which directs to enzymes capable of converting one molecule to another. This scientific breakthrough brings up the question of whether the organism containing the gene that has been modified through a series of tests and experiments should be accredited to the country of origin.
History
Colonial implications
Biopiracy is historically associated with colonialism, where developing resource-rich countries and indigenous populations would be exploited without permission. Since the arrival of European settlers in search of gold, silver, and rare spices, the wealth of knowledge on plant-based riches was highly valued. Following Marco Polo's journey through Southwestern India and China, Christopher Columbus expanded upon the "Spice Route" with the help of the Spanish Court. These explorers, amongst hundreds more, share an infamous history of pillaging through indigenous villages and depriving countries of their natural resources. Western food and pharmaceutical companies have profited immensely from these efforts. Valuable commodities like sugar, pepper, quinine, and coffee were all taken from colonized countries that led to environmental destructions in the corresponding developing countries.
The General Agreement on Tariffs and Trade (GATT) of 1947 was an effort to encourage international trade by reducing or eliminating trade barriers like tariffs or quotas. Trade-Related Intellectual Property Rights (TRIPS) was negotiated at the end of GATT. Similarly, Columbus set a precedent in 1492 through land titles granted by European kings and queens, which acted as a sort of patent for colonizers. The World Trade Organization (WTO) agreement of TRIPS attempts to signal the importance of maintaining a balance between trade and intellectual property. This agreement, since 1994, requires WTO member countries to develop legal frameworks to protect plant and animal resources in agricultural, pharmaceutical, chemical, textile, or other commodity contexts. Several countries have criticized this agreement, claiming that it's counterproductive in protecting their natural resources.
The Eurocentric roots of property claiming and piracy are reinforced by modern Intellectual Property laws established by GATT and WTO which supplements the colonial ideas to "discover and conquer" and to "subdue, occupy, and possess." Environmental activist and food sovereignty advocate Vandana Shiva calls patenting and claiming rights to genetic material and bio-resources "the second coming of Columbus" due to its reinforcement of colonial power dynamics. For example, the intellectual property for Indian products like tamarind, turmeric, and Darjeeling tea have been taken and patented by private corporations in historically colonial countries. More specifically, in 2010 The University of Michigan attempted to patent curcumin, the active ingredient of turmeric powder, to create drugs used for wound healing without directly crediting Indian communities, where turmeric was traditionally used in medicine for treating wounds, infections and skin problems for centuries.
"Gene Rush" in Sri Lanka
The "Gene Rush" is the new era of biotechnology that allows scientists to extract specific genes from living organisms as raw materials. With the introduction of deoxyribonucleic acid (DNA) research, Sri Lanka has been marked with imminent danger as a target of biopiracy. Spotted in the top 34 biodiversity hotspots, Sri Lanka claims the highest biodiversity per unit area of terrestrial among Asian countries. Currently, Sri Lanka has 1,500 identified species of medicinal herbs and plants, and its attraction to biopiracy has put environment protection and conservation at a significant priority in the country. Recent efforts were enacted by United Nations Industrial Development Organization (UNIDO) in collaboration with the Spice Council and the government of Sri Lanka to enhance the productive capacities and competitiveness of the cinnamon value chain in the country.
Terminology
"Biopiracy" was coined in the early 1990s by Pat Mooney, founder of ETC Group which works to protect the world's most vulnerable people from socioeconomic and environmental impacts of new, modern technologies. He defines it as when researchers or research organizations take biological resources without official sanction, largely from less affluent countries or marginalized people. Biopiracy includes theft or misappropriation of genetic resources and traditional knowledge through the intellectual property system and unauthorized and uncompensated collection of genetic resources for commercial purposes. Mooney, along with other critics of the patent system, believes that the current intellectual property system creates inequities in the system by allowing wealthy and powerful groups of people to own the most basic building blocks of life.
Intellectual Property and international law
Intellectual property (IP) rights include patents, copyright, industrial design rights, trademarks, plant variety rights, trade dress, geographical indications, and sometimes trade secrets.
Intellectual property rights (IPR) were created to promote and reward scientific knowledge and creativity. However, they naturally weigh towards benefiting transnational corporations.
Restrictions in favor of corporations
Early intellectual property treaties were crafted in the late 19th century by European powers, and inherently ignored large parts of the impact of intellectual property on non-European peoples, cultures, and traditions.
In the late 20th century, more inequalities were added to the intellectual property system, representing a shift from common rights to private rights of knowledge. The preamble of TRIPS agreement acknowledges these rights as private rights. By privatizing intellectual commons, TRIPS encourages corporate monopoly.
A second restriction comes from the fact that IP rights are only recognized when they generate profit, rather than then when they meet social needs. The TRIPS agreement clarifies that an innovation must be capable of industrial profit in order to be recognized as an IPR, which discourages recognition of social good.
Legal framework against biopiracy in relation to genetic resources and traditional knowledge
In parallel, the international community has been working on different legal pathways to rebalance the intellectual property system in favour of indigenous peoples and local communities, in an attempt to address concerns related to biopiracy.
1992–2010: Biodiversity Convention in Rio & Protocol in Nagoya
First elements related to genetic resources and traditional knowledge were included in the 1992 Convention on Biological Diversity (CBD). In 2010 (in force 2014), the Nagoya protocol to the CBD created actionable mechanisms to ensure a fair access and benefit-sharing (FABS or ABS) of genetic resources (GR).
2023: High Seas Treaty in New York
In June 2023, the UN adopted the United Nations agreement on biodiversity beyond national jurisdiction (BBNJ Agreement), also called "High Seas Treaty". It concerns the conservation and sustainable use of marine biological diversity in areas beyond national jurisdiction, following maritime jurisdictions established under the United Nations Convention on the Law of the Sea.
2024: GRATK Treaty in Geneva
Since 2001, the World Intellectual Property Organization through its Intergovernmental Committee on Intellectual Property and Genetic Resources, Traditional Knowledge and Folklore (IGC) has worked on several areas to bridge the gaps in international law in relation to biopiracy in genetic resources, traditional knowledge (TK), and traditional cultural expressions (TCE, formerly called "folklore").
The first output from the work of the IGC was a Diplomatic Conference, held in May 2024 to agree on a treaty for patent disclosures requirements in relation to "GR and Associated TK" (hence the treaty's acronym, GRATK). On 24 May 2024, the WIPO Diplomatic Conference finally adopted the "landmark" WIPO Treaty on Intellectual Property, Genetic Resources and Associated Traditional Knowledge (GRATK), which was signed by 30 countries on the day of its conclusion.
Examples
Neem tree
In the arid areas of India, the neem tree, or Azadirachta indica, is a fast-growing evergreen of up to 20 meters in height. From its roots to leaves, the tree contains a number of potent chemical compounds, including azadirachtin which can be found in the seeds. The neem tree has applications in medicine, toiletries, contraception, timber, fuel, and in agriculture. Historically, access to the neem tree's various products has been free or cheap. There are about 14 million neem trees in India, and the centuries old village techniques of seed oil extraction and pesticidal emulsions do not require expensive equipment. Villagers relied on the large number of different medicinal compounds accessible through the neem material which were commonly available. When US timber importer Robert Larson noticed the tree's usefulness in 1971, he conducted research over the next decade on the pesticidal properties in the neem extract called Margosan-O. After gaining clearance for the product from the US Environmental Protection Agency (EPA) in 1985, he sold the patent for the product to W.R. Grace. While the corporation patented the neem tree seed extract for their antifungal spray, Neemex in 1994, neem extracts have been used by rural farmers in India for more than 2,000 years in insect repellants.
Challenge against patent
India-based Research Foundation for Science, Technology, and Ecology (RFSTE) challenged the US patent with the claim that the qualities of the neem tree and their use had been known in India for over 2,000 years. The Congressional Research Service (CRS) reported to US Congress in justification of the patent claiming that the synthetic form or the process of synthesis of the naturally occurring compound should be patentable. The patent was finally overturned by the EPO in 2000. The village neem tree has become a symbol of Indian Indigenous knowledge and resistance against transnational corporations, and protestors against international property rights legislation carried twigs or branches of neem.
Hoodia
The Hoodia plant of the Kalahari Desert was used for thousands of years by the nomadic San people in southern Africa to help survive through hunger and thirst during their long expeditions in the desert. In 2016, the South African Council for Scientific and Industrial Research (CSIR) gained a government-funded patent for a new drug (P57) derived from the succulent for its appetite-suppressing qualities. CSIR scientists isolated the P57 molecule in 1996 after decades of research on indigenous plants. The patented formula was sold to western pharmaceutical multinational companies Pfizer and Phytopharm as a miracle drug for weight loss.
Challenge against patent
Following the confirmation of the patent, representatives of the San people, backed by the global support of patent-law critics and bioethicists, demanded restitution of their rights to their common intellectual property. After a long dispute, CSIR and the San people came to a confidential 'benefit-sharing' agreement where the San people were given royalties, knowledge exchange and creation of jobs from the industry.
Pineapple leather
Piña cloth, in the nineteenth century, was a creation unique to the Philippines. With fibers collected from the leaves of pineapples, the weaving mechanism of piña is a complex and labor-intensive process used by a small number of women to dress the country's elite. Scraping, the most common method of extracting pineapple leaf fibre (PALF), starts with carefully removing the prickles, epidermis, and pulp from the sides of the leaf with a dull knife. This is followed by exposing the fiber and finely combing it to separate the strands. With the help of a bamboo device, the separated strands are then threaded and weaved together through a delicate process to create a continuous filament. After some years of research and development of potential leather alternatives at the Royal College of Art in London, Dr. Carmen Hijosa, founder and chief creative innovation officer of Ananas Anam, claimed the rights to Piñatex, a leather alternative made from PALF. The patent on this technology makes it nearly impossible for the people of the Philippines and indigenous people to gain credit for the fabric that greatly impacted the shape of their history and culture for generations. Piñatex recently partnered with Dole, promising scaled-up leather production with the waste product from their pineapple farms in the Philippines. Despite the violent history of the Dole Empire, Piñatex has been expanding its market by collaborating with brands like Chanel, H&M, and Nike. The patent remains to this day.
Corporate greenwashing
Greenwashing is a term coined by environmentalist Jay Westervelt in 1986, meaning the false claims by companies that give the impression of sustainability and environmentalism. Without clarifying the metrics and quantifiable goal of the company's environmental agenda, many big companies attempt to paint the picture of ethical and eco-friendly images. Resources and materials pirated from indigenous communities are often commodified and recycled into corporate environmentalist agendas. Due to the exploitative nature of the fast fashion supply chain, many 'green' collections released by corporations only promote their marketing strategies and increase problems with textile waste and climate change.
Nike received backlash after the 2020 Impact Report which showed the lack of sustainability in footwear. To tackle the feedback, Nike launched the Happy Pineapple Collection featuring Ananas Anam's vegan leather material and a tropical fruit design embroidered across the Air Max 90, the Air Max 95, Air Force One, and Air-Zoom collections.
The Conscious Collection released by H&M in 2010 also partners with Ananas Anam to produce vegan leather jackets. Due to inconclusive data on Piñatex biodegradability, the Norwegian Consumer Authority accused the brand of misleading customers with vague details of the sustainability claims made. The brand responded by saying they would accept the criticism and communicate the extra value.
New efforts
The Convention on Biological Diversity created by the United Nations in 1992 demanded that bioprospecting should not be done without the consent of the host country. The convention concluded that exploitation of local resources for medicinal and pharmaceutical purposes should actively involve local traditional communities and the produced profit and benefits be shared in an equitable way.
The International Cooperative Biodiversity Group (ICBG) is a network of bioprospecting projects funded by the US government. While the main objective is to discover and research plants bearing chemical compounds that could cure diseases in the United States, the countries hosting the searches can expect equitable rewards and benefits. Local job creation in communities is promoted by conducting the initial extraction and analysis steps in local laboratories. If the research leads to commercialized drugs, 50% of the royalties are invested into community development funds run by indigenous people.
See also
Intellectual property
Bioprospecting
Greenwashing
Neo-colonial science
References
Biotechnology
Population genetics | Biopiracy | [
"Biology"
] | 3,363 | [
"Biotechnology",
"nan",
"Biodiversity",
"Biopiracy"
] |
69,023,971 | https://en.wikipedia.org/wiki/Ultra-Black | Ultra-black is one of the darkest shades of the color black. An ultra-black substance is defined as reflecting less than 0.5% of the light that hits its surface. This color is part of the natural coloration of some species of birds-of-paradise, butterflies, and fishes, and ultra-black components are used in telescopes, cameras, and solar panels to improve the efficiency of light capture.
Discovery in fish
The first recorded instance of ultra-black coloration being discovered in a species of fish occurred in 2020, when a group of researchers were examining fishes caught in trawls during research cruises in Monterey Bay, California, and the Gulf of Mexico. A total of 16 out of the 18 species caught in these trawls were found to have skin that reflected less than 0.5% of the light that hit it and that could thus be termed ultra-black. The specimen with the darkest skin, an anglerfish belonging to the genus Oneirodes, also tied some species of birds-of-paradise as having the darkest pigment in any animal, reflecting only 0.044% of the light that hit it. This ultra-black skin may serve several purposes depending on the biology, preferred food sources, and predators of each species. While most of these species likely use this coloration as camouflage to hide from predators, some of them, including fish that attract prey using bioluminescent lures like Astronesthes micropogon and Oneirodes sp., could potentially use ultra-black skin to catch prey unawares and prevent them from being seen in the light from their own lures. In some cases, ultra-black skin might also serve to block light that the fish does not want to emit, with ultra-black skin over the gut potentially blocking light emitted by bioluminescent prey while being digested.
Mechanism
The ultra-black coloration of these deep-sea fishes is due to a pigment called melanin, the same pigment that gives human skin its coloration, and the reason the skin of these fishes is so much darker than human skin is due to both the amount of melanin present and arrangement of the melanin. The skin of the deep-sea fishes contains one layer filled with small organelles called melanosomes that contain melanin, and in these fishes the melanosomes are both larger and more abundant than in other animals, with very few gaps resulting in a solid layer of pigment. The high concentration of the pigment is augmented by the melanosomes being aligned in a way that scatters incoming light sideways into other melanosomes rather than reflecting it directly back, which in turn increases the amount of pigment the light hits before it is reflected out of the fishes’ skin, ultimately reducing the amount of light that the fishes emit. This has a significant effect on reducing the fishes' visibility, and it is estimated that reducing the amount of light that a deep-sea fish reflects from 2% to 0.05% reduces the distance at which the fish can be seen by 84%. What makes these fishes unique from other animals that have ultra-black coloration, like butterflies and birds-of-paradise, is that those animals have structures that capture light and direct it into the melanin in their skin, while the fishes do not have those structures and rely solely on the pigment in their melanosomes to absorb incoming light. Being able to reproduce the mechanism these fishes use to absorb light has industrial applications because the ultra-black products humans make use carbon nanotubes, which are very delicate, to trap light and being able to replace these nanotubes with a pigment-based system would improve the durability of current products and open the door for new applications.
References
Shades of black
Biological pigments | Ultra-Black | [
"Biology"
] | 771 | [
"Biological pigments",
"Pigmentation"
] |
69,024,547 | https://en.wikipedia.org/wiki/Phyllachora%20leveilleana | Phyllachora leveilleana is a species of fungus, a member of the division Ascomycota, and was first described by Ferdinand Theissen and Hans Sydow in 1917. Phyllachora leveilleana belongs to the genus Phyllachora, and family Phyllachoraceae.
References
Phyllachorales
Taxa named by Ferdinand Theissen
Taxa named by Hans Sydow
Fungi described in 1917
Fungus species | Phyllachora leveilleana | [
"Biology"
] | 100 | [
"Fungi",
"Fungus species"
] |
62,377,207 | https://en.wikipedia.org/wiki/Alex%20Kipman | Alex Kipman (born 1979) is a Brazilian engineer and inventor who is the founder and chief executive officer (CEO) of Analog AI. Previously, he was the lead developer of the Microsoft HoloLens smartglasses and helped develop the Xbox Kinect.
Early life and education
Kipman was born in Curitiba in 1979. The son of a Brazilian diplomat, Kipman grew up around the world. When he was seven or eight, he learned how to program the Atari 2600. Later on he would go to RIT, graduating in 2001 with a degree in software engineering.
Career
Kipman joined Microsoft in 2001, starting development on Microsoft's integrated development environment (IDE) Visual Studio. Starting 2005, he helped in the development of Microsoft Windows, until joining the Xbox department in 2008, where he oversaw the acquisition of the technology for the Xbox Kinect from an Israeli company, PrimeSense. The product was finished two years later.
In 2011, Time magazine named him to its list of its 100 Most Influential People in the World, a list consisting of leaders, artists, innovators, icons and heroes. In a subsequent interview with Fast Company, he said "Software is the only art form in existence that is not bound by the confines of physics." In 2012 he was named Inventor of the Year by the Intellectual Property Owners Association.
In 2013, Kipman gave the commencement speech at his alma mater, the Rochester Institute of Technology (RIT).
In 2016, he gave a Ted Talk on mixed reality, called "A futuristic vision of the age of Holograms". In a 2017 interview with Alice Bonasio, he emphasized his passion for mixed reality, stating how it gives him a sense of "displacement superpowers". During the Hololens 2 reveal at the Mobile World Congress in 2019, Alex Kipman talked about how the Hololens 2 would be the "next era" of mixed reality, making it more culturally relevant.
In 2019 while he was developing metaverse technologies, the Smithsonian Institution in Washington, D.C named Kipman the winner of an American Ingenuity Award, calling him a pioneer of holographic and augmented reality technology. Later that year he gave a speech in Shanghai announcing that Microsoft's second-generation HoloLens would ship later that year.
In 2021, he received the Longuet-Higgins Prize by the Pattern Analysis and Machine Intelligence (PAMI) Technical Committee at the Conference on Computer Vision and Pattern Recognition (CVPR) for fundamental contributions in computer vision.
In May 2022, Kipman left Microsoft to found Analog AI. He has been the CEO of Analog AI since 2023. In March 2024, he joined Verses AI as a strategic advisor.
Awards and recognition
Popular Mechanics Breakthrough Award (2009)
Producers Guild of America Digital 25: Visionaries, Innovators and Producers list (2010)
Time Top 25 Nerds of the Year (2010)
Time 2011 100 People of the Year
Fast Company 100 Most Creative People in Business (2011)
National Inventor of the Year, Intellectual Property Foundation (2012)
Rochester Institute of Technology Innovators Hall of Fame (2013)
Smithsonian American Ingenuity Awards (2019)
Longuet-Higgins prize by IEEE for fundamental contributions in computer vision (2021)
References
External links
Fastcompany interview
Ted speech
1979 births
Living people
Software engineers
People from Natal, Rio Grande do Norte
Rochester Institute of Technology alumni
Brazilian engineers
Microsoft technical fellows
Microsoft Windows people
People from Curitiba | Alex Kipman | [
"Engineering"
] | 719 | [
"Software engineering",
"Software engineers"
] |
62,377,460 | https://en.wikipedia.org/wiki/Takeshi%20Saito%20%28mathematician%29 | Takeshi Saito (斎藤 毅 Saitō Takeshi, born 9 September 1961) is a Japanese mathematician, specializing in some areas of number theory and algebraic geometry. His thesis advisor was Kazuya Kato.
Saito was an invited speaker of the International Congress of Mathematicians in 2010.
Selected publications
Articles
Books
References
1961 births
Living people
20th-century Japanese mathematicians
21st-century Japanese mathematicians
Number theorists
University of Tokyo alumni
Academic staff of the University of Tokyo | Takeshi Saito (mathematician) | [
"Mathematics"
] | 92 | [
"Number theorists",
"Number theory"
] |
62,377,463 | https://en.wikipedia.org/wiki/Monocentric%20chromosome | The monocentric chromosome is a chromosome that has only one centromere in a chromosome and forms a narrow constriction.
Monocentric centromeres are the most common structure on highly repetitive DNA in plants and animals.
Structure
Monocentric chromosomes as compared to holocentric chromosomes where the entire length of the chromosome acts as the centromere. In monocentric chromosomes there is one primary constriction and the centromere its CenH3 loci at this location.
Holocentric chromosomes are found throughout the plant and animal kingdoms such as the nematode Caenorhabditis elegans. Holocentric chromosomes do have an evolutionary advantage by preventing the loss of chromosome after a DNA double-strand break.
The centromere is the point of attachment for the mitotic apparatus
Chromosomal aberrations
Deletions, duplications and translocations can produce a polycentric chromosome. This is troublesome for cells that divide often since at the time of anaphase the polycentric chromosome does not move to opposite poles of spindle fiber and the cell dies.
See also
Metacentric
Submetacentric
Acrocentric
Telocentric
References
Chromosomes
Classical genetics
DNA replication | Monocentric chromosome | [
"Biology"
] | 243 | [
"Genetics techniques",
"DNA replication",
"Molecular genetics"
] |
62,377,568 | https://en.wikipedia.org/wiki/Solvent%20vapour%20annealing | Solvent vapor annealing (SVA) is a widely used technique for controlling the morphology and ordering of block copolymer (BCP) films. By controlling the block ratio (f = NA/N), spheres, cylinders, gyroids , and lamellae structures can be generated by forming a swollen and mobile layer of thin-film from added solvent vapor to facilitate the self-assembly of the polymer blocks. The process allows increased lateral ordering by several magnitudes to previous methods. It is a more mild alternative to thermal annealing.
Ideally, the chamber in which SVA takes place is a metal chamber that is inert to reaction with the given solvent, allowing for high precision in forming the desired nanostructures. Computers with designed program control of the valves for solvent addition and withdrawal are used to increase precision as well. This regulated inlet along with close monitoring of pressure gauges and thickness allows instant response and control while the annealing and evaporation phases precede.
Factors Affecting SVA
When looking at what affects SVA, one of the main things that come up first is the solvent that is used, and what nanostructure is wanted to be obtained. For example, if a hierarchical structure is desired, a solvent that has a vapor that can selectively mobilize the amorphous polymer chains of a semi-crystalline polymer is ideal because it can also keep the integrity of the crystals, allowing for the secondary structure to form.
Looking more at BCP itself, they make ordered nanostructures because of thermodynamic differences between different blocks of the polymer. The sample morphology at equilibrium can be predicted using the molar mass of the blocks, the degree of polymerization of the chains (N), and the Flory-Huggins interaction parameter (χ) which is a magnitude of exactly how incompatible the different blocks are. These factors, along with the composition of the BCP, allow microphase separation of chains and the rearrangement into the desired product. The composition provides an especially important part of the process as knowing the ordering, such as alternating AB monomers, gives light on how to section the polymer in the desired manner.
Along with this, the selection of a specific type of block polymer is important for the process and its effectiveness. The main thing to consider is the original structure of the block at room temperature, as well as, temperatures in which each block will begin to change phase. Knowing these temperatures is critical in determining when each will begin to react and take in solvent and at what rate this will happen, which is critical in pushing to a desired morphology of the given block polymer through annealing.
Other factors that affect SVA are parameters such as vapor pressure, solvent concertation in the film, and evaporation rate of the solvent. Each of these factors contributes to the volatility and imprecision at times of this method, not possessing a set mechanism for the construction of structures that are desired, such as nanocylinders. Getting perfect success of the desired morphology of a polymer has yet to be achieved with these plethoras of factors dictating formation.
Applications
There are many applications in technology and lab work for this process to create desired morphologies of polymers. One of these applications is inscribing secondary nanostructures onto electrospun fibers. The use of poly(ε‐caprolactone) fibers, known as PCL, allows using solvents like acetone to move the amorphous chains of block polymers onto a pre-existing crystal, making the inscribed secondary structure. When the PCL is annealed with acetone, the amorphous chains can be mobilized to a given desired region, while the overall integrity of the fully crystallized regions stays intact. With a careful approach to the semi-crystalline polymer chosen and looking for appropriate solvent vapor, this simple process can be applied to many different systems and allows for the creation of many types of hierarchical polymer material.
Another application of SVA is its use in helping create and improve photovoltaic device efficiency through the annealing of perovskite materials. For the greater performance of these energy cells, the keys lie with higher quality perovskite materials and on the use of SVA to create these higher quality films that can retain energy more efficiently. Solvent engineering is the key to make the perovskite material and improving their quality through SVA in an anhydrous isopropanol environment, where the crystalline polymer has low solubility, which causes the performance to increase greatly. The use of SVA here leads to a more energy-efficient and promising path of using specific polymers to help move forward with the improvement of energy storage.
Challenges and Areas to Focus on for Improvement
There are some main areas of focus that can be looked at for the future of SVA to keep improving and being innovational in technology. Firstly, the chambers in which SVA takes place should continue to be improved on to allow precision of the process, as well as, reproducibility of the same structure on each attempt. The focus on these chambers and the components that make it precise have been a hypothetical thought process of what parameters affect reproducibility. It is imperative to continue to improve the amount of control over the annealing through being able to control all factors, such as humidity and temperature. The point of being meticulous in defining such parameters is for the possibility of multiple labs reproducing a certain compound to the same effect.
Next off, SVA with the improvement of the apparatus in which the process takes place, in situ studies, through X-ray and neutron scattering methods, can give more highly accurate images of the swollen and dried states of the BCP. Using methods such as also ellipsometry and interferometry can lead to discoveries about the thickness of the polymers in different states and nanostructure orientation, which will help to learn more about the equilibrium structure and the kinetics of developing a specified morphology. It is important here as well to be able to define small molecule additions to different parts of the block polymer at different points of the annealing and evaporation as to accurately be able to precisely know how the moieties will create certain orientations and directionality in structure. The final area moving forward is simply the implementation of the created block polymers in new intended applications and technology, beyond lab study and characterization of the method. It is important to go beyond creating the nanostructures and move into seeing the utility of the structures in an application, which will help reveal practical shortcomings of the created polymers and reveal areas of where to improve in parts of the structure, such as film integrity and attachment strength of the amorphous chains. Going beyond these simple surface imaging will allow us to realize and face some of the dangers and hindrances to functionality, such as the toxicity of working with organic solvents or the issues with dewetting the swollen state of the BCP.
References
Copolymers
Polymer chemistry | Solvent vapour annealing | [
"Chemistry",
"Materials_science",
"Engineering"
] | 1,434 | [
"Materials science",
"Polymer chemistry"
] |
62,378,017 | https://en.wikipedia.org/wiki/Tong%20Sun | Tong Sun (born 1968) is a Professor of Sensor Engineering and Director of the Research Centre for Photonics and Instrumentation at City, University of London. She was awarded the Royal Academy of Engineering Silver Medal in 2016 and awarded an Order of the British Empire (OBE) in the 2018 Birthday Honours. In 2020 she was elected Fellow of the Royal Academy of Engineering.
Early life and education
Sun was born in Southern China. By the time she attended primary school, the Cultural Revolution had finished and the educational system had been restored. Sun studied engineering at the Harbin Institute of Technology. Here she worked in the Department of Precision Instrumentation, where she earned a master's degree in 1993 and doctorate in 1998. On her holidays from university, Sun's commute back to her parents' house would last 34 hours. She moved to City, University of London for a second doctorate, during which she researched optical fibres, and graduated in 1999.
Research and career
After earning her doctorate Sun joined Nanyang Technological University where she worked as an Assistant Professor until 2001. She moved back to City, University of London in 2001. When she was promoted to Professor in 2008 she became the first woman to be promoted to Professor of engineering at City. She also serves as Director of the Research Centre for Photonics and Instrumentation.
Her research involves the development of optical fibre sensors to monitor sensitive equipment in extreme environments. Her research has contributed to several different technologies, including drug detection, corrosion monitoring and combating food spoilage. She has worked with the Home Office and Smiths Group. In 2007 Sun co-founded Sengenia Ltd, a fibre sensing spin-out. She has developed humidity sensors that can withstand challenging environments such as acidic sewers in Sydney and rice stores in China. Sun continues to work with researchers at the Shandong Academy of Sciences on the implementation of optical fibres in the mining industry . In 2017 Sun was awarded the Australian Water Safety Council New South Wales Water Award to trial her sensors in Sydney Water. She is working with AECOM and Indian Institutes of Technology to enhance the sustainability of cities in India. This research was recognised with one of the most successful projects funded by the UK-India Education Research Initiative.
Sun designed a sensor system that could be used to measure strain and temperature in pantographs, the connectors that are used to link overhead power cables in for electric trains. These devices are essential for train function and routine checks can miss important information. The optical sensors developed by Sun can continuously monitor pantograph behaviour during operation. The instrumented pantographs developed by Sun are currently being developed by Brecknell Willis.
In 2018 Sun was awarded a Royal Academy of Engineering Research Chair to work with Brecknell Willis on new railway electrification systems. Sun is working on contactless electrification systems that integrate optical fibre sensors for continuous, in situ all-weather monitoring. The first pantographs went on service trial in 2019 and included Global Positioning System and video equipment. In 2019 they were awarded funding from the Railway Industry Association, Rail Safety and Standards Board and Innovate UK. Sun was shortlisted for the Times Higher Education Research Supervisor of the Year.
Awards and honours
Her awards and honours include;
2008 Elected Fellow of the Institution of Engineering and Technology
2016 Royal Academy of Engineering Silver Medal
2018 Order of the British Empire for services to engineering
2020 Elected Fellow of the Royal Academy of Engineering
Selective publications
Her publications include;
References
1968 births
Living people
Chinese emigrants to England
Chinese women engineers
Fellows of the Royal Academy of Engineering
Female fellows of the Royal Academy of Engineering
Fellows of the Institution of Engineering and Technology
Sensor manufacturers
Academics of City, University of London
Alumni of City, University of London
Harbin Institute of Technology alumni
Officers of the Order of the British Empire | Tong Sun | [
"Engineering"
] | 750 | [
"Institution of Engineering and Technology",
"Fellows of the Institution of Engineering and Technology"
] |
62,379,097 | https://en.wikipedia.org/wiki/Memory-hard%20function | In cryptography, a memory-hard function (MHF) is a function that costs a significant amount of memory to efficiently evaluate. It differs from a memory-bound function, which incurs cost by slowing down computation through memory latency. MHFs have found use in key stretching and proof of work as their increased memory requirements significantly reduce the computational efficiency advantage of custom hardware over general-purpose hardware compared to non-MHFs.
Introduction
MHFs are designed to consume large amounts of memory on a computer in order to reduce the effectiveness of parallel computing. In order to evaluate the function using less memory, a significant time penalty is incurred. As each MHF computation requires a large amount of memory, the number of function computations that can occur simultaneously is limited by the amount of available memory. This reduces the efficiency of specialised hardware, such as application-specific integrated circuits and graphics processing units, which utilise parallelisation, in computing a MHF for a large number of inputs, such as when brute-forcing password hashes or mining cryptocurrency.
Motivation and examples
Bitcoin's proof-of-work uses repeated evaluation of the SHA-256 function, but modern general-purpose processors, such as off-the-shelf CPUs, are inefficient when computing a fixed function many times over. Specialized hardware, such as application-specific integrated circuits (ASICs) designed for Bitcoin mining, can use 30,000 times less energy per hash than x86 CPUs whilst having much greater hash rates. This led to concerns about the centralization of mining for Bitcoin and other cryptocurrencies. Because of this inequality between miners using ASICs and miners using CPUs or off-the shelf hardware, designers of later proof-of-work systems utilised hash functions for which it was difficult to construct ASICs that could evaluate the hash function significantly faster than a CPU.
As memory cost is platform-independent, MHFs have found use in cryptocurrency mining, such as for Litecoin, which uses scrypt as its hash function. They are also useful in password hashing because they significantly increase the cost of trying many possible passwords against a leaked database of hashed passwords without significantly increasing the computation time for legitimate users.
Measuring memory hardness
There are various ways to measure the memory hardness of a function. One commonly seen measure is cumulative memory complexity (CMC). In a parallel model, CMC is the sum of the memory required to compute a function over every time step of the computation.
Other viable measures include integrating memory usage against time and measuring memory bandwidth consumption on a memory bus. Functions requiring high memory bandwidth are sometimes referred to as "bandwidth-hard functions".
Variants
MHFs can be categorized into two different groups based on their evaluation patterns: data-dependent memory-hard functions (dMHF) and data-independent memory-hard functions (iMHF). As opposed to iMHFs, the memory access pattern of a dMHF depends on the function input, such as the password provided to a key derivation function. Examples of dMHFs are scrypt and Argon2d, while examples of iMHFs are Argon2i and catena. Many of these MHFs have been designed to be used as password hashing functions because of their memory hardness.
A notable problem with dMHFs is that they are prone to side-channel attacks such as cache timing. This has resulted in a preference for using iMHFs when hashing passwords. However, iMHFs have been mathematically proven to have weaker memory hardness properties than dMHFs.
References
Cryptography | Memory-hard function | [
"Mathematics",
"Engineering"
] | 764 | [
"Applied mathematics",
"Cryptography",
"Cybersecurity engineering"
] |
62,379,583 | https://en.wikipedia.org/wiki/Animals%20in%20War%20%26%20Peace%20Medal%20of%20Bravery | The Animals in War & Peace Medal of Bravery was instituted in 2019 in the United States by Robin Hutton and Mari Lou Livingood to honor the work of American animals in war and peace. The medal was created to be the American equivalent of the Dickin Medal, awarded in the UK for any animal displaying conspicuous gallantry and devotion to duty particularly in the armed forces or civil emergency services.
Recipients
The first recipients received their awards on November 14, 2019, either posthumously or in person at a ceremony attended by dignitaries and members of Congress on Capitol Hill in Washington, D.C. The event was sponsored by Angels Without Wings, Inc., The Livingood Group, and the National Marine Corps League. Organizers, members of Congress and animal handlers present called it a historic day and that the awards were long overdue.
The recipients included two pigeons, five dogs, and a horse. G.I. Joe, one of the pigeons, died almost 60 years ago, but during World War II, he saved the lives of over one hundred Allied forces by flying 20 miles in 20 minutes to "deliver a message that aborted an imminent bombing by friendly forces". The horse, Sergeant Reckless, served with the U.S. Marines in numerous combat actions during the Korean War, carrying supplies and ammunition, and was also used to evacuate wounded. "Let the record show: Sergeant Reckless was a lot more courageous than I," said former senator John Warner in presenting the award in honor of the revered horse.
Other posthumous medals were awarded to Chips, a pet husky mix who served in World War II; Stormy, a German Shepherd who helped capture enemy soldiers during the Vietnam War; and Lucca, an IED-detecting dog who protected thousands of human lives as part of her assignments in Iraq and Afghanistan. On her last mission in 2012, when she was on patrol in Afghanistan, she sniffed out a 30-pound (13.6-kilogram) IED and was continuing her search when she lost one of her legs when another IED detonated underneath her. Cpl. Juan Rodriguez, her handler, thought she had been killed, but was able to rescue her.
Two living animals were at the ceremony for their awards: Bucca, a former stray who overcame a rough past to become a star arson-detecting K-9 for the New York Fire Department, and Bass, a Belgian Malinois who held the rare position of "multipurpose canine" in the Marine Corps' Special Operations Command until retiring in October 2019. Bass was accompanied by his handler, Staff Sgt. Alex Schnell. Bass served four deployments with in Afghanistan, Iraq and Somalia from 2014 to 2019.
At the 2019 ceremony, a campaign was initiated to create an International Animals in War and Peace Museum that will recognize animal heroism in war and peace.
At the second medal ceremony on March 9, 2022, six dogs received either the Medal of Bravery or the new Distinguished Service Medal. One of the dogs had served in World War II, one in the Vietnam War, and one was on the raid that eliminated Osama bin Laden; the other three were all recently active, and attended the ceremony. Three of the dogs received the Medal of Bravery.
Medal of Bravery
Distinguished Service Medal
A second medal, the Animals in War & Peace Distinguished Service Medal, was introduced at the 2022 ceremony, for animals who have distinguished themselves by "exceptionally meritorious service to the U.S in a duty of great responsibility", and was awarded to three dogs.
See also
Dogs in warfare
Horses in warfare
References
Military animals
Awards established in 2019
Awards to animals
Lists of animals
2019 establishments in the United States | Animals in War & Peace Medal of Bravery | [
"Biology"
] | 736 | [
"Lists of biota",
"Lists of animals",
"Animals"
] |
62,379,588 | https://en.wikipedia.org/wiki/Rotary%20atomizers | Rotary atomizers use a high speed rotating disk, cup or wheel to discharge liquid at high speed to the perimeter, forming a hollow cone spray. The rotational speed controls the drop size. Spray drying and spray painting are the most important and common uses of this technology.
Many industries need to convert a large mass of liquid into a dispersion of small (micron-size) droplets (generate a spray). Some examples of this need are evaporative cooling, meteorology, printing, medical applications, spray combustion, coating, and drying. Various devices exist to generate sprays, such as atomizers, sprayers, nozzles, and applicators. Sprays are typically generated by producing a high speed difference between the phase of gases and the liquid to be atomized. These devices achieve this atomization by releasing the liquid at very high speed into the unagitated air. The liquid can also be atomized by using a reverse process, instead of accelerating the liquid, gas can be accelerated to achieve a relatively higher speed than the liquid. The devices using this method to achieve atomization are called as airblast, air-assist, or popularly twin-fluid atomizers. In a Rotary Atomizer, the rotating cup or disc forces the liquid to come out at a very high speed through its rim.
The Rotary, Pressure-swirl or Twin-fluid Atomizers are the most common methods for spray generation. For special applications, alternative atomizer types exist such as the electrostatic atomizer in which electrical pressure is used to drive the atomization, and the ultrasonic atomizing device in which the liquid is passed through a transducer vibrating at ultrasonic frequencies to generate shorter wavelengths which convert the fluid into smaller droplets. Since the flow rate of liquid is low in both of these devices, their applications are limited.
Working Principle
Rotary atomizers work on the principle of centrifugal energy; this energy is used to produce a high relative speed between the fluid and air which is essential for atomization. A rotary atomizer comprises a rotating surface. This surface can be in the form of a flat or a vaned disc, a cup, or a slotted wheel. A basic rotary atomizer is displayed in the figure.
The liquid first flows radially outwards in the disc and is then released from the disc's outer limits at a relatively very high speed. The atomization relies on the liquid's flow rate and the disc's rotational speed. The fluid is released from the disc's outer limits as uniform-sized droplets at low flow rates. At a comparatively high flow rate, ligaments are generated along the disc's outer limits which later on break into smaller droplets. When the flow rate is further increased, the ligaments become unable to fit in with the liquid flow, and hence a fine sheet of liquid is produced which expands past the disc's rim. This sheet, later on, disintegrates into ligaments and finally, drops are formed. The transition from ligament to sheet formation can be delayed by ragging the disc's edges. Rotary atomizers belong to the mechanical atomizers; hence, neither a high-pressure liquid nor a pressurized gas is required for atomization. The energy required for atomization is transferred directly from the atomizer body to the liquid. This gives us an advantage that the energy required for atomizing the liquid is directly supplied mechanically and energetically. The complicated and costly production of compressed gas, for example, compressed air, is no longer necessary. It is sufficient to feed the liquid to be atomized to the atomizer under low pressure. Sometimes a low hydrostatic pressure is adequate.
Working Formulae
The spray generated by a device like a rotary atomizer can be viewed as liquid droplets submerged in a continuous phase of gases. The size of droplet formed by atomizer depends on various properties of the fluid (both liquid and gaseous fluid) such as density, viscosity and surface tension between fluids.
Generally, small gas turbines operate under high rotational speed of more than 100,000 rpm. Even small-sized atomizer of 10 cm diameter revolving at 30,000 rpm can impart an acceleration of 490, 000 m/s2 (which is fifty thousand times of gravity) on the liquid fuel. Eventually, such fuel atomizers create very tiny droplets. The rotary atomizer in which liquid is revolving along with it at the rate of ω and has radial channels at nominal radius R=(R1+R2)/2 in the edge from which high-speed liquid interacts with gas to form droplets.
Considering the nominal radius of the channel and thus of mass of liquid inside channel equal to R, the liquid inside channel will experience the centrifugal acceleration of Rω2, which causes the liquid to form a thin layer of thickness t on both walls of the channel. At very high acceleration thickness of the liquid layer (film) is very small in order μm. The shape of the channel also decides the effectiveness of atomization and the size of droplets. That is one aspect of determining the size of the droplet is the velocity of liquid in the channel (v=Rω).
So, we have four dimensionless terms derived from the above properties which determine the performance of atomization.
1. Liquid-gas density ratio
r = [ρL / ρG] where ρL and ρG are densities of liquid and gas respectively
2. Viscosity ratio
m = [μL / μG] where, μL and μG are viscosities of liquid and gas respectively
3. Weber Number
Wet = [ρG Vc2 t/σs] where σs is surface tension between liquid and gas contact surface. It is the ratio of the force applied by the gas on the liquid layer to the surface tension force acting on liquid.
4. Ohnesorge Number
Oht= [μL / (ρL σs t) 1/2]
It is the ratio of viscous force inside the layer to the surface tension force acting on liquid. Altogether, all these terms describe three main phenomena of atomization viz., inertia, viscous diffusion and surface tension. For practical fuel atomizer, Ohnesorge number is limited to Oht<<1 and the size of the droplet are not much affected by Ohnesorge number. So, viscous effects can be neglected. But Weber number can't be neglected since surface tension and inertia are the major phenomena of the atomization process.
For small values of We, surface tension is dominant, and this force pulls the liquid towards the wall of the channel, making a single column that eventually breaks after meeting air resulting in comparatively larger droplets. This is known as the subcritical breakup of liquid. Whereas, for the supercritical breakup of liquid (more significant values of We), force applied by gas is dominant for breaking of liquid which results in fine small size of droplets.
Features of a Rotary Atomizer
Because of the breakup energy which the wheel's high-speed supplies in liquid feed systems, they can run at relatively low pressure. The atomizer drive gives the high speed to the wheel.
Clogging can be a problem for spray nozzle systems, whereas rotary atomizers can work in such situations.
A rotary atomizer can manage large amounts of abrasive and non-abrasive feeds.
A rotary atomizer can take very viscous liquids.
A rotary atomizer is flexible according to particle size. It can be modified from 5 μ to 150 μ by changing the wheel speed.
A rotary atomizer can give different powder characteristics and bulk density by equipping with different wheel designs.
A rotary atomizer can be fitted with a wide variety of wheels with various designs and sizes for abrasive and non-abrasive feeds.
Applications
Industrial Finishing
Rotary atomizer technology is found often on paint lines in the industrial finishing industry. A rotary atomizer is mounted to a paint robot or a reciprocator. Often call a Rotary bell atomizer, this paint applicator is often paired with electrostatic technology in order to maximize transfer efficiency of the paint. Rotary atomizers spin at extremely high speeds to break up the paint into fine, even particle sizes. Leading to a very high quality, consistent finish. This technology is used to paint a variety of industries including automotive, aerospace, aluminum extrusion, agricultural equipment, cosmetics, household cookware, electronics and more.
References
Fluid mechanics
Turbomachinery | Rotary atomizers | [
"Chemistry",
"Engineering"
] | 1,745 | [
"Turbomachinery",
"Chemical equipment",
"Civil engineering",
"Mechanical engineering",
"Fluid mechanics"
] |
62,380,390 | https://en.wikipedia.org/wiki/Bulgy%20the%20Whale | Bulgy the Whale is a children's amusement ride manufactured by Eyerly Aircraft Company. It consists of eight whale-shaped ride vehicles traveling in a counter-clockwise rotation, similar to a carousel, while traveling up and down small hills. Although the Eyerly Aircraft Company ceased operation in the 1980s, there are still several Bulgy the Whale rides in operation. Some have had their whales repainted to resemble fish instead of whales, and others have had thematic pieces added, but the general operation and idea remains the same.
Bulgy the Whale Installations
Below is a partial list of Bulgy the Whale attractions.
References
Amusement rides | Bulgy the Whale | [
"Physics",
"Technology"
] | 131 | [
"Physical systems",
"Machines",
"Amusement rides"
] |
62,380,746 | https://en.wikipedia.org/wiki/Induced%20cell%20cycle%20arrest | Induced cell cycle arrest is the use of a chemical or genetic manipulation to artificially halt progression through the cell cycle. Cellular processes like genome duplication and cell division stop. It can be temporary or permanent. It is an artificial activation of naturally occurring cell cycle checkpoints, induced by exogenous stimuli controlled by an experimenter.
Model organisms
In an academic research context, cell cycle arrest is typically performed in model organisms and cell extracts, such as Saccharomyces cerevisiae (yeast) or Xenopus oocytes (frog eggs). Frog egg cell extracts have been used extensively in cell cycle research because they are relatively large, reaching a diameter of 1mm, and so contain large amounts of protein, making protein levels more easily measurable.
Purposes
There are a variety of reasons a researcher may want to temporarily or permanently prevent progress through the cell cycle.
Cell cycle synchronization
In some experiments, a researcher may want to control and synchronize the time when a group of cells progress to the next phase of the cell cycle. The cells can be induced to arrest as they arrive (at different time points) at a certain phase, so that when the arrest is lifted (for instance, rescuing cell cycle progression by introducing another chemical) all the cells resume cell cycle progression at the same time. In addition to this method acting as a scientific control for when the cells resume the cell cycle, this can be used to investigate necessity and sufficiency.
Another reason synchrony is important is the control for amount of DNA content, which varies at different parts of the cell cycle based on whether DNA replication has occurred since the last round of completed mitosis and cytokinesis.
Furthermore, synchronization of large numbers of cells into the same phase allows for the collection of large enough groups of cells in the same cycle for the use in other assays, such as western blot and RNA sequencing.
DNA damage repair
Researchers may be investigating mechanisms of DNA damage repair. Given that some of the mechanisms below of inducing cell cycle arrest involve damaging the DNA, this allows investigation into how the cell responds to damage of its genetic material.
Identification of in vivo protein function
Genetic engineering of cells with specific gene knockouts can also result in cells that arrest at different phases of the cell cycle. Examples include:
G1: Saccharomyces cerevisiae yeast expressing dominant mutant alleles of CDC28 arrest in G1, which indicates that CDC28 is necessary for passage beyond the G1 phase.
S: Schizosaccharomyces pombe (fission yeast) expressing a temperature-sensitive mutant form of DNA polymerase delta (pol delta ts03) arrest in S phase.
G2: Fission yeast expressing some mutant forms of CDC2 unable to arrest in G2 in response to DNA damage, indicating the gene product is involved in G2 arrest.
M: A mutant screen of budding yeasts with mitotic arrest identified CDC16, CDC23, and CDC27 as key genes that, when mutated, cause arrest in mitosis.
G1 phase arrest
G1 phase is the first of the four phases of the cell cycle, and is part of interphase. While in G1 the cell synthesizes messenger RNA (mRNA) and proteins in preparation for subsequent steps of interphase leading to mitosis. In human somatic cells, the cell cycle lasts about 18 hours, and the G1 phase makes up about 1/3 of that time. On the other hand, in frog, sea urchin, and fruit fly embryos, the G1 phase is extremely brief and instead is a slight gap between cytokinesis and S phase.
Alpha Factor
α-factor is a pheromone secreted by Saccharomyces cerevisiae that arrests the yeast cells in G1 phase. It does so by inhibiting the enzyme adenylate cyclase. The enzyme catalyzes the conversion of adenosine triphosphate (ATP) to 3',5'-cyclic AMP (cAMP) and pyrophosphate.
Contact inhibition
Contact inhibition is a method of arresting cells when neighboring cells come into contact with each other. It results in a single layer of arrested cells of arrested cells, and is a process that is notably missing in cancer cells. The suspected mechanism is dependent on p27Kip1, a cyclin-dependent kinase inhibitor. p27Kip1 protein levels are elevated in arresting cells. This natural process can be mimicked in a lab through the overexpression of p27Kip1, which results in induced cell cycle arrest in G1 phase.
Mimosine
Mimosine is a plant amino acid that has been shown to reversibly inhibit progression beyond G1 phase in some human cells, including lymphoblastoid cells. Its proposed mechanism of action is an iron/zinc chelator that depletes iron within the cell. This induces double-strand breaks in the DNA, inhibiting DNA replication. This may involve blocking the action of an iron-dependent ribonucleotide reductase. It may also inhibit transcription of serine hydroxymethyltransferase, which has zinc dependence.
Serum deprivation
In cell culture, serum is the growth medium in which the cells are grown and contains vital nutrients. The use of serum deprivation - partially or completely removing the serum and its nutrients - has been shown to arrest and synchronize cell cycle progression in G0 phase, for example in neonatal mammalian astrocytes and human foreskin fibroblasts.
Amino acid starvation is a similar approach. When grown in a media without some essential amino acids, such as methionine, some cells arrest in early G1 phase.
S phase arrest
S phase follows G1 phase via the G1/S transition and precedes G2 phase in interphase and is the part of the cell cycle in which DNA is replicated. Since accurate duplication of the genome is critical to successful cell division, the processes that occur during S-phase are tightly regulated and widely conserved. Pre-replication complexes assembled before S phase are converted into active replication forks. Driving this conversion is Cdc7 and S-phase cyclin-dependent kinases, which are both upregulated after the G1/S transition.
Aphidicolin
Aphidicolin is an antibiotic isolated from the fungus Cephalosporum aphidicola. It is a reversible inhibitor of eukaryotic nuclear DNA replication that blocks progression past the S phase. Its mechanism is the inhibition of DNA polymerase A and D. A structural study found that this is thought to occur through binding the alpha active site of the polymerase and "rotating the template guanine," which prevents deoxycytidine triphosphate (dCTP) from binding. This S phase block induces apoptosis in HeLa cells.
Hydroxyurea
Hydroxyurea (HU) is a small molecule drug that inhibits the enzyme ribonucleotide reductase (RNR), preventing the catalysis of converting deoxyribonucleotides (DNTs) to ribonucleotides. It is hypothesized that there is tyrosyl free radical within RNR that is disabled by HU. The free radicals are necessary for the reduction of the DNTs and are scavenged by HU instead. HU has been shown to arrest cells in both S phase (healthy cells) and immediately before cytokinesis (mutant cells).
2,3-DCPE
23-(2,3-dichlorophenoxy)propyl aminoethanol (2,3-DCPE) is a small-molecule that induces S phase arrest. This was demonstrated in cancer cell lines and downregulates expression of B-cell lymphoma-extra large (Bcl-XL), an anti-apoptotic protein that prevents the release of mitochondrial contents like cytochrome c.
G2 phase arrest
G2 phase is the final part of interphase and directly precedes mitosis. It will only be entered in regular cells if the DNA replication in S phase is completed successfully. It is a period of rapid cell growth and protein synthesis during which the cell prepares itself for mitosis.
Destruction of cyclin mRNA
Cyclins are proteins that control progression through the cell cycle by activating cyclin-dependent kinases. Destruction of a cell's endogenous cyclin messenger RNA can arrest frog egg extracts in interphase and prevent them from entering mitosis. Introduction of exogenous cyclin mRNA is also sufficient to rescue cell cycle progression. One method of this destruction is through the use of antisense oligonucleotides, pieces of RNA that bind to the cyclin mRNA and prevent the mRNA from being translated into cyclin protein. This can actually be used to destroy phase-specific cyclins beyond just G2 - for instance, destruction of cyclin D1 mRNA by antisense oligonucleotides prevents progression from G1 phase to S phase.
Mitotic arrest
Mitosis is the final part of the cell cycle and follows interphase. It is composed of four phases - prophase, metaphase, anaphase, and telophase - and involves the condensation of the chromosomes in the nucleus, the dissolution of the nuclear envelope, and the separation of sister chromatids by spindle fibers. As mitosis concludes, the spindle fibers disappear and the nuclear membrane reforms around each of the two sets of chromosomes. After successful mitosis, the cell physically splits into two identical daughter cells in a process called cytokinesis, and this concludes a full round of the cell cycle. Each of these new cells could then potentially re-enter G1 phase and begin the cell cycle again.
Nocodazole
Nocodazole is a chemical agent that interferes with the polymerization of microtubules. Cells treated with nocodazole arrest with a G2 or M phase DNA content, which can be verified with flow cytometry. From microscopy it has been determined they do enter mitosis but they cannot form the spindles necessary for metaphase because the microtubules cannot polymerize. Research into the mechanism has hinted at it potentially preventing tubulin from forming its alpha/beta heterodimer.
Taxol
Taxol works in the opposite way of nocodazole, instead stabilizing the microtubule polymer and preventing it from disassembly. It also causes M phase arrest, as the spindle that is supposed to pull apart sister chromatids is unable to disassemble. It acts through a specific binding site on the microtubule polymer, and as such does not require GTP or other cofactors to induce tubulin polymerization.
Temperature
Temperature has been shown to regulate HeLa cell cycle progression. Mitosis was found to be the most temperature-sensitive part of the cell cycle. Pre-cytokinesis mitotic arrest was visible through accumulation of cells in mitosis in below-normal temperatures between 24 and 31 °C (75.2-87.8 °F).
Verification
There are several methods that can be used to verify that cells have been arrested in the proper phase.
Flow cytometry
Flow cytometry is a technique of measuring physical and chemical characteristics of a population of cells using lasers and fluorophore dyes covalently linked to protein markers. The stronger the signal, the more of a particular protein is present. Staining with DNA dyes propidium iodide or 4',6'-diamidino-2-phenylindole (DAPI) allows delineation or sorting of cells between G1, S, or G2/M phases.
Immunoblotting
Immunoblotting is the detection of specific proteins in a tissue sample or extract. Primary antibodies recognize and bind the protein in question, and secondary antibodies are added that recognize the primary antibodies. The secondary antibody is then visualized through staining or immunofluorescence, allowing indirect detection of the original target protein.
Immunoblotting can be performed to detect the presence of cyclins, proteins that regulate the cell cycle. Different classes of cyclins are up- and down-regulated at different parts of the cell cycle. Measurement of the cyclins from an extract of an arrested cell can determine what phase the cell is in. For example, a peak of cyclin E protein would indicate the G1/S transition, a cyclin A peak would indicate late G2 phase, and a cyclin B peak would indicate mitosis.
Fluorescence ubiquitination-based cell cycle indication (FUCCI)
FUCCI is a system that takes advantage of cell cycle phase-specific expression of proteins and their degradation by the ubiquitin-proteasome pathway. Two fluorescent probes - Cdt1 and Geminin conjugated to fluorescent proteins - allow for real-time visualization of the cell cycle phase a cell is in.
References
Cell cycle
Cell biology
Laboratory techniques | Induced cell cycle arrest | [
"Chemistry",
"Biology"
] | 2,725 | [
"Cell cycle",
"Cell biology",
"Cellular processes",
"nan"
] |
62,381,917 | https://en.wikipedia.org/wiki/Software%20bot | A software bot is a type of software agent in the service of software project management and software engineering. A software bot has an identity and potentially personified aspects in order to serve their stakeholders. Software bots often compose software services and provide an alternative user interface, which is sometimes, but not necessarily conversational.
Software bots are typically used to execute tasks, suggest actions, engage in dialogue, and promote social and cultural aspects of a software project.
The term bot is derived from robot. However, robots act in the physical world and software bots act only in digital spaces. Some software bots are designed and behave as chatbots, but not all chatbots are software bots. Erlenhov et al. discuss the past and future of software bots and show that software bots have been adopted for many years.
Usage
Software bots are used to support development activities, such as communication among software developers and automation of repetitive tasks. Software bots have been adopted by several communities related to software development, such as open-source communities on GitHub and Stack Overflow.
GitHub bots have user accounts and can open, close, or comment on pull requests and issues. GitHub bots have been used to assign reviewers, ask contributors to sign the Contributor License Agreement, report continuous integration failures, review code and pull requests, welcome newcomers, run automated tests, merge pull requests, fix bugs and vulnerabilities, etc.
The Slack tool includes an API for developing software bots. There are slack bots for keeping track of todo lists, coordinating standup meetings, and managing support tickets. The
ChatBot company products further simplify the process of creating a custom Slack bot.
On Wikipedia, Wikipedia bots automate a variety of tasks, such as creating stub articles, consistently updating the format of multiple articles, and so on. Bots like ClueBot NG are capable of recognizing vandalism and automatically remove disruptive content.
Taxonomies and Classification Frameworks
Lebeuf et al. provide a faceted taxonomy to characterize bots based on a literature review. It is composed of 3 main facets: (i) properties of the environment that the bot was created in; (ii) intrinsic properties of the bot itself; and (iii) the bot's interactions within its environment. They further detail the facets into sets of sub-facets under each of the main facets.
Paikari and van der Hoek defined a set of dimensions to enable comparison of software bots, applied specifically to chatbots. It resulted in six dimensions:
Type: the main purpose of the bot (information, collaboration, or automation)
Direction of the "conversation" (input, output, or bi-directional)
Guidance (human-mediated, or autonomous)
Predictability (deterministic, or evolving)
Interaction style (dull, alternate vocabulary, relationship-builder, human-like)
Communication channel (text, voice, or both)
Erlenhov et al. raised the question of the difference between a bot and simple automation, since much research done in the name of software bots uses the term bot to describe various different tools and sometimes things are "just" plain old development tools. After interviewing and surveying over 100 developers the authors found that not one, but three definitions dominated the community. They created three personas based on these definitions and the difference between what the three personas see as being a bot is mainly the association with a different
set of human-like traits.
The chat bot persona (Charlie) primarily thinks of bots as tools that communicates with the developer through a natural language interface (typically voice or chat), and caring little about what tasks the bot is used for or how it actually implements these tasks.
The autonomous bot persona (Alex) thinks of bots as tools that work on their own (without requiring much input from a developer) on a task that would normally be done by a human.
The smart bot persona (Sam) separates bots and plain old development tools through how smart (technically sophisticated) a tool is. Sam cares less about how the tool communicates, but more about if it is unusually good or adaptive at executing a task.
The authors recommends that people doing research or writing about bots try to put their work in the context of one of the personas since the personas have different expectations and problems with the tools.
Example of notable bots
Dependabot and Renovatebot update software dependencies and detect vulnerabilities. (https://dependabot.com/)
Probot is an organization that create and maintain bots for GitHub. The example bots using Probot are the following.
Auto Assign (https://probot.github.io/apps/auto-assign/)
license bot (https://probot.github.io/)
Sentiment bot (https://probot.github.io/apps/sentiment-bot/)
Untrivializer bot (https://probot.github.io/apps/untrivializer/)
Refactoring-Bot (Refactoring-Bot): provides refactoring based on static code analysis
Looks good to me bot (LGTM) is a Semmle product that inspects pull requests on GitHub for code style and unsafe code practices.
Issues and threats
Software bots may not be well accepted by humans. A study from the University of Antwerp has compared how developers active on Stack Overflow perceive answers generated by software bots. They find that developers perceive the quality of software bot-generated answers to be significantly worse if the identity of the software bot is made apparent. By contrast, answers from software bots with human-like identity were better received. In practice, when software bots are used on platforms like GitHub or Wikipedia, their username makes it clear that they are bots, e.g., DependaBot, RenovateBot, DatBot, SineBot.
Bots may be subject to special rules. For instance, the GitHub terms of service does not allow `bot` but accepts `machine account`, where a `machine account` has two properties: 1) a human takes full responsibility of the bot's actions 2) it cannot create other accounts.
See also
Chatbot
ChatBot
Daemon
Internet bot
Software agent
References
Software engineering | Software bot | [
"Technology",
"Engineering"
] | 1,317 | [
"Software engineering",
"Systems engineering",
"Information technology",
"Computer engineering"
] |
62,382,505 | https://en.wikipedia.org/wiki/Van%20Vleck%20paramagnetism | In condensed matter and atomic physics, Van Vleck paramagnetism refers to a positive and temperature-independent contribution to the magnetic susceptibility of a material, derived from second order corrections to the Zeeman interaction. The quantum mechanical theory was developed by John Hasbrouck Van Vleck between the 1920s and the 1930s to explain the magnetic response of gaseous nitric oxide () and of rare-earth salts. Alongside other magnetic effects like Paul Langevin's formulas for paramagnetism (Curie's law) and diamagnetism, Van Vleck discovered an additional paramagnetic contribution of the same order as Langevin's diamagnetism. Van Vleck contribution is usually important for systems with one electron short of being half filled and this contribution vanishes for elements with closed shells.
Description
The magnetization of a material under an external small magnetic field is approximately described by
where is the magnetic susceptibility. When a magnetic field is applied to a paramagnetic material, its magnetization is parallel to the magnetic field and . For a diamagnetic material, the magnetization opposes the field, and .
Experimental measurements show that most non-magnetic materials have a susceptibility that behaves in the following way:
,
where is the absolute temperature; are constant, and , while can be positive, negative or null. Van Vleck paramagnetism often refers to systems where and .
Derivation
The Hamiltonian for an electron in a static homogeneous magnetic field in an atom is usually composed of three terms
where is the vacuum permeability, is the Bohr magneton, is the g-factor, is the elementary charge, is the electron mass, is the orbital angular momentum operator, the spin and is the component of the position operator orthogonal to the magnetic field. The Hamiltonian has three terms, the first one is the unperturbed Hamiltonian without the magnetic field, the second one is proportional to , and the third one is proportional to . In order to obtain the ground state of the system, one can treat exactly, and treat the magnetic field dependent terms using perturbation theory. Note that for strong magnetic fields, Paschen-Back effect dominates.
First order perturbation theory
First order perturbation theory on the second term of the Hamiltonian (proportional to ) for electrons bound to an atom, gives a positive correction to energy given by
where is the ground state, is the Landé g-factor of the ground state and is the total angular momentum operator (see Wigner–Eckart theorem). This correction leads to what is known as Langevin paramagnetism (the quantum theory is sometimes called Brillouin paramagnetism), that leads to a positive magnetic susceptibility. For sufficiently large temperatures, this contribution is described by Curie's law:
,
a susceptibility that is inversely proportional to the temperature , where is the material dependent Curie constant. If the ground state has no total angular momentum there is no Curie contribution and other terms dominate.
The first perturbation theory on the third term of the Hamiltonian (proportional to ), leads to a negative response (magnetization that opposes the magnetic field). Usually known as Larmor or Langenvin diamagnetism:
where is another constant proportional to the number of atoms per unit volume, and is the mean squared radius of the atom. Note that Larmor susceptibility does not depend on the temperature.
Second order: Van Vleck susceptibility
While Curie and Larmor susceptibilities were well understood from experimental measurements, J.H. Van Vleck noticed that the calculation above was incomplete. If is taken as the perturbation parameter, the calculation must include all orders of perturbation up to the same power of . As Larmor diamagnetism comes from first order perturbation of the , one must calculate second order perturbation of the term:
where the sum goes over all excited degenerate states , and are the energies of the excited states and the ground state, respectively, the sum excludes the state , where . Historically, J.H. Van Vleck called this term the "high frequency matrix elements".
In this way, Van Vleck susceptibility comes from the second order energy correction, and can be written as
where is the number density, and and are the projection of the spin and orbital angular momentum in the direction of the magnetic field, respectively.
In this way, , as the signs of Larmor and Van Vleck susceptibilities are opposite, the sign of depends on the specific properties of the material.
General formula and Van Vleck criteria
For a more general system (molecules, complex systems), the paramagnetic susceptibility for an ensemble of independent magnetic moments can be written as
where
,
,
and is the Landé g-factor of state i. Van Vleck summarizes the results of this formula in four cases, depending on the temperature:
if all , where is Boltzmann constant, the susceptibility follows Curie law: ;
if all , the susceptibility is independent of the temperature;
if all is either or , the susceptibility has a mixed behavior and where is a constant;
if all , there is no simple dependence on .
While molecular oxygen and nitric oxide are similar paramagnetic gases, follows Curie law as in case (a), while , deviates slightly from it. In 1927, Van Vleck considered to be in case (d) and obtained a more precise prediction of its susceptibility using the formula above.
Systems of interest
The standard example of Van Vleck paramagnetism are europium(III) oxide () salts where there are six 4f electrons in trivalent europium ions. The ground state of that has a total azimuthal quantum number and Curie's contribution () vanishes, the first excited state with is very close to the ground state at 330 K and contributes through second order corrections as showed by Van Vleck. A similar effect is observed in samarium salts ( ions). In the actinides, Van Vleck paramagnetism is also important in and which have a localized 5f6 configuration.
References
Atomic physics
Electric and magnetic fields in matter
Eponymous equations of physics | Van Vleck paramagnetism | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 1,330 | [
"Equations of physics",
"Eponymous equations of physics",
"Electric and magnetic fields in matter",
"Quantum mechanics",
"Materials science",
"Condensed matter physics",
" molecular",
"Atomic physics",
"Atomic",
" and optical physics"
] |
62,383,372 | https://en.wikipedia.org/wiki/Scanning%20quantum%20dot%20microscopy | Scanning quantum dot microscopy (SQDM) is a scanning probe microscopy (SPM) that is used to image nanoscale electric potential distributions on surfaces. The method quantifies surface potential variations via their influence on the potential of a quantum dot (QD) attached to the apex of the scanned probe. SQDM allows, for example, the quantification of surface dipoles originating from individual adatoms, molecules, or nanostructures. This gives insights into surface and interface mechanisms such as reconstruction or relaxation, mechanical distortion, charge transfer and chemical interaction. Measuring electric potential distributions is also relevant for characterizing organic and inorganic semiconductor devices which feature electric dipole layers at the relevant interfaces. The probe to surface distance in SQDM ranges from 2 nm to 10 nm and therefore allows imaging on non-planar surfaces or, e.g., of biomolecules with a distinct 3D structure. Related imaging techniques are Kelvin Probe Force Microscopy (KPFM) and Electrostatic Force Microscopy (EFM).
Working principle
In SQDM, the relation between the potential at the QD and the surface potential (the quantity of interest) is described by a boundary value problem of electrostatics. The boundary is given by the surfaces of sample and probe assumed to be connected at infinity. Then, the potential of a point-like QD at can be expressed using the Green's function formalism as a sum over volume and surface integrals, where denotes the volume enclosed by and is the surface normal.
In this expression, depends on the charge density inside and on the potential on weighted by the Green's function
where satisfies the Laplace equation.
By specifying and thus defining the boundary conditions, these equations can be used to obtain the relation between and the surface potential for more specific measurement situations. The combination of a conductive probe and a conductive surface, a situation characterized by Dirichlet boundary conditions, has been described in detail.
Conceptually, the relation between and links data in the imaging plane, obtained by reading out the QD potential, to data in the object surface - the surface potential. If the sample surface is approximated as locally flat and the relation between and therefore translationally invariant, the recovery of the object surface information from the imaging plane information is a deconvolution with a point spread function defined by the boundary value problem. In the specific case of a conductive boundary, the mutual screening of surface potentials by tip and surface lead to an exponential drop-off of the point spread function. This causes the exceptionally high lateral resolution of SQDM at large tip-surface separations compared to, for example, KPFM.
Practical implementation
Two methods have been reported to obtain the imaging plane information, i.e., the variations in the QD potential as the probe is scanned over the surface. In the compensation technique, is held at a constant value . The influence of the laterally varying surface potentials on is actively compensated by continuously adjusting the global sample potential via an external bias voltage . is chosen such that it matches a discrete transition of the QD charge state and the corresponding change in probe-sample force is used in non-contact atomic force microscopy to verify a correct compensation.
In an alternative method, the vertical component of the electric field at the QD position is mapped by measuring the energy shift of a specific optical transition of the QD which occurs due to the Stark effect. This method requires an additional optical setup in addition to the SPM setup.
The object plane image can be interpreted as a variation of the work function, the surface potential, or the surface dipole density. The equivalence of these quantities is given by the Helmholtz equation. Within the surface dipole density interpretation, surface dipoles of individual nanostructures can be obtained by integration over a sufficiently large surface area.
Topographic information from SQDM
In the compensation technique, the influence of the global sample potential on depends on the shape of the sample surface in a way that is defined by the corresponding boundary value problem. On a non-planar surface, changes in can therefore not uniquely be assigned to either a change in surface potential or in surface topography if only a single charge state transition is tracked. For example, a protrusion in the surface affects the QD potential since the gating by works more efficiently if the QD is placed above the protrusion. If two transitions are used in the compensation technique the contributions of surface topography and potential can be disentangled and both quantities can be obtained unambiguously. The topographic information obtained via the compensation technique is an effective dielectric topography of metallic nature which is defined by the geometric topography and the dielectric properties of the sample surface or of a nanostructure.
References
External links
https://www.fz-juelich.de/pgi/pgi-3/EN/Groups/LTSTM/Research/SQDM.html
https://poggiolab.unibas.ch/research/Scanning%20Quantum%20Dot%20Microscopy/
http://momalab.org/index.php/?action=devices
Scanning probe microscopy | Scanning quantum dot microscopy | [
"Chemistry",
"Materials_science"
] | 1,065 | [
"Nanotechnology",
"Scanning probe microscopy",
"Microscopy"
] |
62,383,595 | https://en.wikipedia.org/wiki/Centre%20for%20Radiation%2C%20Chemical%20and%20Environmental%20Hazards | The Centre for Radiation, Chemical and Environmental Hazards (CRCE) is a British government environmental research site, run by Public Health England (PHE) in Chilton, Oxfordshire that monitors levels of toxic chemicals and background radiation in the British environment; it is largely a continuation of the former National Radiological Protection Board (NRPB).
History
The Radiation Protection Division of the Health Protection Agency was formed on 1 April 2005, due to the Health Protection Agency Act 2004, directly superseding the NRPB. This became the CRCE due to the Health and Social Care Act 2012, when Public Health England was formed.
Structure
It is part of PHE's Radiation Protection Adviser Services. PHE was the UK's first Radiation Protection Adviser Body, under the Ionising Radiations Regulations (IRR) 17 (which came from the International Commission on Radiological Protection).
Function
It monitors background radiation in the UK. Workers exposed to radiation include workers in dental radiography and nuclear power stations; exposure to radiation for workers in the UK must be ALARP. It offers 3-day training courses around twice a month, at a national level, for workers exposed to radiation.
It produces reports on environmental background radiation in England. It works with the ICRP, the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), and the International Atomic Energy Agency (IAEA). Inside the UK, it works with the Scottish Environment Protection Agency (SEPA) and the Environment Agency (EA).
See also
British Institute of Radiology
Health effects of radon
International Radon Project
NHS Health Research Authority
UK Health Security Agency
References
External links
Radiation Protection Adviser Services
UK Radon
Education in Oxfordshire
Environmental chemistry
Environmental organisations based in the United Kingdom
Environmental research institutes
Environmental toxicology
Nuclear medicine organizations
Nuclear research institutes in the United Kingdom
UK Health Security Agency
Radiation protection organizations
Radiology organizations
Radon
Research institutes in Oxfordshire
Toxicology in the United Kingdom
Vale of White Horse | Centre for Radiation, Chemical and Environmental Hazards | [
"Chemistry",
"Engineering",
"Environmental_science"
] | 396 | [
"Toxicology",
"Nuclear organizations",
"Environmental research institutes",
"Toxicology in the United Kingdom",
"Nuclear medicine organizations",
"Environmental chemistry",
"Environmental toxicology",
"nan",
"Radiation protection organizations",
"Environmental research"
] |
62,384,154 | https://en.wikipedia.org/wiki/Cytocentrifuge | A cytocentrifuge, sometimes referred to as a cytospin, is a specialized centrifuge used to concentrate cells in fluid specimens onto a microscope slide so that they can be stained and examined. Cytocentrifuges are used in various areas of the clinical laboratory, such as cytopathology, hematology and microbiology, as well as in biological research. The method can be used on many different types of specimens, including fine needle aspirates, cerebrospinal fluid, serous and synovial fluid, and urine.
Procedure
To prepare cytocentrifuge smears, a funnel assembly is attached to the front of a microscope slide. The surface of the funnel assembly that is in contact with the slide is lined with filter paper to absorb excess fluid. A few drops of fluid are placed in the funnel. The assembly is placed in the cytocentrifuge, which operates at a low force (600–800 x g) to preserve cellular structure. Centrifugal force pushes the fluid through the funnel's opening and concentrates the cells in a small area of the slide. The centrifugation process concentrates cells by about twenty-fold and creates a one-cell-thick monolayer, allowing for assessment of cellular morphology. The slide can then be fixed and stained.
Applications
Some applications of cytocentrifuges include:
Performing differential cell counts on body fluids, such as serous, synovial and cerebrospinal fluid
Cytopathology examination of liquid specimens such as body fluids and fine needle aspirates
Gram staining of fluid specimens for identification of microorganisms
Limitations
The cytocentrifugation process can cause cells to appear distorted. Cells located at the centre of the smear may look compressed compared to cells at the periphery. Cell nuclei may develop artifactual clefts, lobes, or holes, and the cytoplasm may appear vacuolated or develop irregular projections. Cytoplasmic granules may be pushed to the periphery of the cell. If the cell count is high, cells may be distorted due to crowding; therefore, samples with high cell counts are diluted prior to smear preparation.
History
Examination of cells in body fluids was historically performed using a hemocytometer, a chamber designed for counting cells microscopically. This technique was limited by poor discrimination between cell types (cells could only be classified as mononuclear or polymorphonuclear) and the low number of cells present in unconcentrated body fluids. Moreover, this technique did not produce a permanent record of the specimen. In a 1966 paper, Watson P. described the first cytocentrifuge, calling it "an apparatus for concentrating cells in suspension onto a microscope slide". The device was sold commercially in the 1970s and in 1983 it was patented by Shandon (now Thermo Scientific). As of 2012, numerous brands of cytocentrifuge exist on the market.
References
Centrifuges
Medical devices
Cytopathology | Cytocentrifuge | [
"Chemistry",
"Engineering",
"Biology"
] | 632 | [
"Centrifugation",
"Chemical equipment",
"Medical devices",
"Centrifuges",
"Medical technology"
] |
62,384,924 | https://en.wikipedia.org/wiki/Subspecies%20of%20brown%20bear | Formerly or currently considered subspecies or populations of brown bears (ursus arctos) have been listed as follows:
List
Eurasia and North Africa
North America
Ecotypes or regional populations
Brown bear size, most often measured in body mass, is highly variable and is correlated to extent of food access. Therefore, bears whose range in areas with access to openings, cover, and moisture or water are on average larger, whereas those bears that range into enclosed forested areas or arid, sparsely vegetated regions, both of which tend to be suboptimal foraging habitat for brown bears, average smaller. The brown bear in northern Europe (i.e., Scandinavia, eastern Europe, western Russia), Yellowstone National Park or interior Alaska seasonally weigh on average between , from mean low adult female weights in spring to male bear mean high weights in fall. Brown bears from the Yukon Delta, interior British Columbia, Jasper National Park and southern Europe (i.e., Spain, the Balkans) can weigh from on average. These mass variations represent only two widespread subspecies, the grizzly bear in North America and the Eurasian brown bear in Europe. Due to the lack of genetic variation within subspecies, the environmental conditions in a given area likely plays the largest part in such weight variations.
The grizzly is especially variable in size, as grizzlies from the largest populations, i.e., interior Alaska, with the heaviest weights recorded in Nelchina, Alaska, nearly three times heavier in males than the smallest grizzlies from Alberta, Canada's Jasper National Park. Between the sexes, the grizzlies of Nelchina average around , whereas the Jasper grizzlies averaged about . The enclosed taiga habitat of Jasper presumably is sub-optimal foraging habitat for grizzlies, requiring them to range widely and feed sparsely, thus reducing body weights and putting bears at risk of starvation, while in surfaces areas in the tundra and prairie are apparently ideal for feeding. Even elsewhere in Alberta, weights averaging more than twice those of Jasper grizzlies have been recorded. A gradual diminishment in body size is noted in grizzly bears from the sub-Arctic zone, from the Brooks Range to the Mackenzie Mountains, presumably because food becomes much sparser in such regions, although perhaps the most northerly recorded grizzly bears ever, in the Northwest Territories, was a large and healthy male weighing , more than twice as much as an average male weighs near the Arctic Circle. Data from Eurasia similarly indicates a diminished body mass in sub-Arctic brown bears, based on the weights of bears from northern Finland and Yakutia.
Head-and-body length in grizzly bears averages from while in Eurasian brown bears it similarly averages from . Adult shoulder height averaged in Yellowstone (for any bear measured five or more years old) and a median of (for adults only 10 or more years old) in Slovakia. Standing on its hindlegs, a posture only assumed occasionally, typically-sized brown bears can reportedly range from in standing height. Exceptionally large inland specimens have been reported in several parts of North America, Europe, Russia and even Hokkaido. The largest recorded grizzlies from Yellowstone and Washington both weighed approximately and Eastern European bears have been weighed in Slovakia and Bulgaria of up to , about double the average weight for male bears in these regions. Among the grizzly and Eurasian brown bear subspecies, the largest reportedly shot from each being and , respectively. The latter bear, from Western Russia, reportedly measured just under in head-and-body length.
In Eurasia, the size of bears roughly increases from the west to the east, with the largest bears there native to Eastern Russia. Even in the nominate subspecies, size increases in the eastern limits, with mature male bears in Arkhangelsk Oblast and Bashkortostan commonly exceeding . Other bears of intermediate size may occur in inland populations of Russia. Much like the grizzly bear and Eurasian brown bear, populations of the Ussuri brown bear (U. a. lasiotus) and the East Siberian brown bear (U. a. collaris) may vary widely in size. In some cases, the big adult males of these populations may have matched the Kodiak bear in size. East Siberian brown bears from outside the sub-Arctic and mainland Ussuri brown bears average about the same size as the largest-bodied populations of grizzly bears, i.e., those of similar latitude in Alaska, and have been credited with weights ranging from throughout the seasons. On the other hand, the Ussuri brown bears found in the insular population of Hokkaido are usually quite small, usually weighing less than , exactly half the weight reported for male Ussuri brown bears from Khabarovsk Krai. This is due presumably to the enclosed mixed forest habitat of Hokkaido. A similarly diminished size has been reported in East Siberian brown bears from Yakutia, as even adult males average around , thus about 40% less than the average weight of male bears of this subtype from central Siberia and the Chukchi Peninsula.
In linear measurements and mean body mass, several subspecies may vie for the title of smallest subtype, although thus far, their reported body masses broadly overlaps with those of the smaller-bodied populations of Eurasian brown bears and grizzly bears. Leopold (1959) described the now-extinct Mexican grizzly bear (U. a. nelsoni) that, according to Rausch (1963), as the smallest subtype of grizzly bear in North America, although the exact parameters of its body size are not known today. Bears of the Syrian subspecies (U. a. syriacus) will reportedly weigh around in adulthood. The Himalayan brown bear (U. a. isabellinus) is another rival for the smallest subspecies; in Pakistan, this subtype averages about in females and in males. Himalayan brown bear females were cited with an average head-and-body length of merely . Brown bears of the compact Gobi Desert population, which is not usually listed as a distinct subspecies in recent decades, weigh around between the sexes, so they are similar in weight to bears from the Himalayas and even heavier than grizzlies from Jasper National Park. However, the Gobi bear has been reported to measure as small as in head-and-body length, which, if accurate, would make them the smallest known brown bear in linear dimensions. These smallest brown bear subtypes are characteristically found in "barren-ground" type habitats, i.e., sub-desert in bears of the Syrian subspecies and the Gobi subtype and arid alpine meadow in Himalayan brown bears.
The largest subspecies are the Kodiak bear (U. a. middendorffi) and the questionably-distinct peninsular giant bear or coastal brown bear (U. a. gyas). Also, the extinct California grizzly bear (U. a. californicus) was rather large. Once mature, the typical female Kodiak bear can range in body mass from and from sexual maturity onward, males range from . According to the Guinness Book of World Records the average male Kodiak bear is in total length (head-to-tail) and has a shoulder height of . When averaged between their spring low and fall high weights from both localities, males from Kodiak island and coastal Alaska weighed from with a mean body mass of while the same figures in females were with a mean body mass of . By the time they reach or exceed eight to nine years of age, male Kodiak bears tend to be much larger than newly mature six-year-old males, potentially tripling their average weight within three years' time, and can expect to average between . The reported mean adult body masses for both sexes of the polar bear are very similar to the peninsular giant and Kodiak bears. Due to their roughly corresponding body sizes, the two subtypes and the species can both legitimately be considered the largest living member of the bear family Ursidae and the largest extant terrestrial carnivores. The largest widely accepted size for a wild Kodiak bear, as well as for a brown bear, was for a bear killed in English Bay on Kodiak Island in fall 1894 as several measurements were made of this bear, including a body mass of , and a hind foot and a voucher skull were examined and verified by the Guinness Book of World Records. Claims have been made of larger brown bears, but these appear to be poorly documented and unverified and some, even if recited by reputable authors, may be dubious hunters' claims.
The largest variety of brown bear from Eurasia is the Kamchatkan brown bear (U. a. beringianus). In the Kamchatkan brown bears from past decades, old males have been known to reach a body mass of by fall, putting the subtype well within Kodiak bear sizes and leading it to be considered the largest of the extant Russian subtypes. However, a diminishment in body size of U. a. berigianus has been noted, mostly likely in correlation with overhunting. In the 1960s and 1970s, most adult Kamchatkan brown bears weighed merely between ; however, mean weights of mature male bears have been reported as averaging in 2005.
References
Brown bears
Lists of animals
Subspecies | Subspecies of brown bear | [
"Biology"
] | 1,902 | [
"Lists of biota",
"Lists of animals",
"Animals"
] |
62,385,494 | https://en.wikipedia.org/wiki/Desag%C3%BCe | The Desagüe was the hydraulic engineering project to drain Mexico's central lake system in order to protect the capital from persistent and destructive flooding. Begun in the sixteenth century and completed in the late nineteenth century, it has been deemed "the greatest engineering project of colonial Spanish America." Historian Charles Gibson goes further and considers it "one of the largest engineering enterprises of pre-industrial society anywhere in the world." There had been periodic flooding of the prehispanic Aztec capital of Tenochtitlan, the site which became the Spanish capital of Mexico City. Flooding continued to be a threat to the viceregal capital, so at the start of the seventeenth century, the crown ordered a solution to the problem that entailed the employment of massive numbers of indigenous laborers who were compelled to work on the drainage project. The crown also devoted significant funding. A tunnel and later a surface drainage system diverted flood waters outside the closed basin of Mexico. Not until the late nineteenth century under Porfirio Díaz (1876-1911) was the project completed by British entrepreneur and engineer, Weetman Pearson, using machinery imported from Great Britain and other technology at a cost of 16 million pesos, a vast sum at the time. The ecological impact was long lasting, with desiccation permanently changing the ecology of the Basin of Mexico.
Early history
In the period before the Spanish conquest, the Aztec capital of Tenochtitlan had been subject to flooding during prolonged rains. There was no natural drainage of the lake system outside the closed basin. In the late 1440s, the ruler of Tenochtitlan, Moctezuma I, and the ruler of the allied kingdom of Texcoco, Nezahualcoyotl, ordered a dike (albarradón) to be constructed, which was expanded under the rule of Ahuitzotl. The dike was in place when the Spanish conquered Tenochtitlan in 1521, but major flooding in 1555-56 prompted the construction of a second dike. The Spanish made plans for diverting flood waters following that flooding, but took no action. Post-conquest damage to the surrounding watershed by the cutting of trees and the silting of the lake likely exacerbated the existing tendencies toward flooding. Flooding in 1604 and 1607 damaged buildings in the capital and crown officials took steps to devote capital and labor into solving the problem. Since forced indigenous labor was a resource that the crown could draw on, thousands of indigenous men were put to work digging a tunnel to divert flood waters. The operation was similar to mining work. The crown also engaged a Dutch engineer, Adrian Boot, to assess the problem. The Netherlands were part of the Spanish Hapsburg Empire, so it is not surprising that a Dutch expertise was brought to bear. Boot recommended reverting to a dike to control flooding. Work was begun on one, but huge rains in 1628 overtook the project. Mexico City was in crisis. Food was scarce. Most of the population fled, and buildings collapsed. The crown even proposed moving the capital to the mainland. The tunnel was converted to an open cut trench. In the decade of the greatest crisis, the crown $1.5 million pesos on the Desagüe, with the labor of an untold number of indigenous workers, but certainly numbering in the tens of thousands. The crown put an end to coerced agricultural labor, but continued with compulsory labor for the Desagüe. A section of the colonial archives in Mexico City are devoted to the documentation on the Desagüe.
Nineteenth and twentieth centuries
With Mexican independence from Spain in 1821, the Mexican state ended compulsory indigenous labors. The need for maintenance of the Desagüe open cut drainage continued in the post-independence era. With political stability achieved under President Porfirio Díaz, the Desagüe became a centerpiece of Mexico's drive for modernity. It was inaugurated with great fanfare in 1900, touted as one of the great achievements of the modern era in Mexico. With Mexico City's location at the low point of the basin of Mexico, drainage of rainwater, industrial waste from tanneries and abattoirs, and human sewage concentrated there. Awareness that such pollution posed a risk and was a major impediment to Mexico's project of modernization, the daunting task was to find a solution. Although flood waters had long been a physical threat to the capital, in the late nineteenth century, they were also now seen as a threat to urban sanitation and public health. Infant mortality was high as was general mortality in the capital when the government tackled anew the drainage project. Initially a network of dikes and holding tanks was tried hold back excess water was tried, but was unsuccessful. Work during the colonial era was by manpower wielding hand tools of shovels and pickaxes, and progress was limited due to the high water table that quickly filled the drainage ditch. Much of Mexican modernization during the Porfiriato relied on foreign expertise and capital. British entrepreneur Weetman Pearson, instrumental in developing Mexico's petroleum industry, imported British-made machinery that was assembled in Mexico. Mechanization of digging overcame previous limitations. The project saw the construction of a deep and straight trench in the basin of Mexico and construction of a tunnel through the eastern mountains. A massive dredge 40 meters long, made of timbers and booms, with a steam engine mounted on the deck was used. The machinery had 40 buckets in a line to dredge sludge from the bottom of the cut, raised it to the surface, and then discharge it into train cars to be deposited elsewhere. The surface cut was 47 kilometers long, with the tunnel through the mountains another 10 kilometers.
See also
History of Mexico City
New Spain
Water supply and sanitation in Mexico
References
Further reading
Aréchiga Córdoba, Ernesto. 2004. "El desagüe del Valle de México, siglos XVI-XXI: Una historia paradójica." Arqueología mexicana 12.68:60-65.
Boyer, Richard. 1975. La gran inundación: Vida y sociedad en México, 1629-1638.
Candiani, Vera. 2012. "The desagüe reconsidered: Environmental dimensions of class conflict in colonial Mexico." Hispanic American Historical Review 92.1 pp. 5–39.
Cohen, M. P. 1999. El paradigma porfiriano: historia del desagüe del valle de México. UNAM.
Gibson, Charles. 1964. The Aztecs under Spanish Rule: A History of the Indians of the Valley of Mexico, 1519-1810. Stanford University Press.
González Navarro, Moisés. 1955. "México en una laguna". Historia Mexicana 4, no. 4 (April – June) pp. 506–522.
González Obregón, L. 1902. Memoria histórica, técnica y administrativa de las obras del desagüe del valle de México 1449-1900. Vol. 2. Tip. de la Oficina impresora de estampillas, 1902.
Hoberman, Louisa. 1974. "Bureaucracy and Disaster: Mexico City and the Flood of 1629." Journal of Latin American Studies 6 211–230.
Hoberman, Louisa. 1980. Technological change in a traditional society: the case of the desagüe in colonial Mexico. Technology and Culture, 386–407.
Lacroix, Jorge Gurría. El desagüe del valle de México durante la época novohispana. No. 19. UNAM, 1978.
Maldonado Aranda, Salvador. "Efectos perversos de las políticas hidráulicas en México: desagüe residual del Valle de México y la creación de un distrito de riego." Nueva antropología 19.64 (2005): 75–97.
Manuel, Perló. (1999) "El paradigma porfiriano. Historia del desagüe del valle de México." Mexico: Instituto de Investigaciones Sociales, Miguel Angel Porrúa.
Mathes, W. Michael. (1970). "To save a city: the Desagüe of Mexico-Huehuetoca, 1607." The Americas, 26(4), 419–438.
Miller, Shawn William, An Environmental History of Latin America. New York: Cambridge University Press 2007
Simon, Joel. (1997) Endangered Mexico: an Environment on the Edge. San Francisco: Sierra Club Books.
Tortolero Villaseñor, Alejandro. (2004) "Transforming the Central Mexican Waterscape: Lake Drainage and Its Consequences during the Porfiriato," in Territories, Commodities and Knowledges: Latin American Environmental Histories in the Nineteenth and Twentieth Centuries, ed. Christian Brannstrom Washington, DC: Brookings Institution Press, pp. 121–147.
Colonial Mexico
Hydraulic engineering
1900 in Mexico | Desagüe | [
"Physics",
"Engineering",
"Environmental_science"
] | 1,831 | [
"Hydrology",
"Physical systems",
"Hydraulics",
"Civil engineering",
"Hydraulic engineering"
] |
62,387,071 | https://en.wikipedia.org/wiki/Don%27t%20Look%20Up | Don't Look Up is a 2021 American apocalyptic political satire black comedy film written, co-produced, and directed by Adam McKay from a story he co-wrote with David Sirota. It stars an ensemble cast featuring Leonardo DiCaprio, Jennifer Lawrence, Rob Morgan, Jonah Hill, Mark Rylance, Tyler Perry, Timothée Chalamet, Ron Perlman, Ariana Grande, Kid Cudi, Cate Blanchett, and Meryl Streep. The film tells the story of two astronomers attempting to warn humanity about an approaching comet that will destroy human civilization. The impact event is an allegory for climate change, and the film is a satire of government, political, celebrity, and media indifference to the climate crisis.
Produced by McKay's Hyperobject Industries and Bluegrass Films, the film was announced in November 2019. Originally set for a theatrical release by Paramount Pictures, the distribution rights were acquired by Netflix several months later. Lawrence became the first member of the cast to join, with DiCaprio signing on after his discussions with McKay on adjustments to the script; the rest of the cast was added through 2020. Filming was initially set to begin in April 2020 in Massachusetts, but it was delayed due to the COVID-19 pandemic; it eventually began in November 2020 and wrapped in February 2021.
Don't Look Up began a limited theatrical release on December 10, 2021, before streaming on Netflix on December 24. It was praised for the cast's performances and the musical score, but critics were divided on the merits of McKay's satire; some found it deft, while others criticized it as smug and heavy-handed. Don't Look Up was named one of the top ten films of 2021 by the National Board of Review and American Film Institute. It received four Academy Award nominations (including Best Picture), four Golden Globe Award nominations (including Best Picture – Musical or Comedy), six Critics' Choice Award nominations, (including Best Picture), and also won Best Original Screenplay at the 74th Writers Guild of America Awards. The film set a new record for the most viewing hours in a single week on Netflix, and went on to become the second-most-watched movie on Netflix within 28 days of release.
Plot
Kate Dibiasky, a doctoral candidate in astronomy at Michigan State University, discovers an unknown comet. Her professor, Doctor Randall Mindy, confirms that it will collide with Earth in approximately six months and is large enough to cause a global extinction event. NASA verifies the findings, and Dr. Teddy Oglethorpe, head of their Planetary Defense Coordination Office, accompanies Dibiasky and Mindy to present their findings to the White House. However, they are met with apathy from President Janie Orlean and her Chief of Staff Jason Orlean, who is also her son.
Oglethorpe encourages Dibiasky and Mindy to leak the news to the media, which they then do, on The Daily Rip, a popular morning talk show. When hosts Jack Bremmer and Brie Evantee treat the topic lightly, Dibiasky loses her temper and angrily rants about the threat before she flees the scene. Mindy receives public approval for his looks, while Dibiasky becomes the subject of negative memes for her on-air behavior. Actual news about the comet's threat receives little public attention, and the danger is denied by Orlean's NASA Director Jocelyn Calder, a top donor to Orlean with no background in astronomy. When news of Orlean's sex scandal with her Supreme Court nominee Sheriff Conlon is exposed, she distracts from the bad publicity by finally confirming the threat and announcing a project to strike and divert the comet using nuclear weapons.
The mission successfully launches, but Orlean abruptly aborts it when Peter Isherwell, the billionaire CEO of BASH Cellular and another top donor, discovers that the comet contains trillions of dollars worth of rare-earth elements. The White House agrees to commercially exploit the comet by fragmenting and recovering it from the ocean, using technology proposed by BASH in a scheme that has not undergone peer review. Orlean sidelines Dibiasky and Oglethorpe while hiring Mindy as the National Science Advisor. Dibiasky attempts to mobilize public opposition to the scheme but gives up under threat from Orlean's administration. Mindy becomes a prominent voice advocating for the comet's commercial opportunities and begins an affair with Evantee.
World opinion is divided among people who believe the comet is a severe threat, those who decry alarmism and believe that mining a destroyed comet will create jobs, and those who deny that the comet even exists. When Dibiasky returns home to Illinois, her parents kick her out of the house and she begins a relationship with a young man named Yule, a shoplifter she meets at her retail job. After Mindy's wife confronts him about his infidelity, she returns to Michigan without him. Mindy questions whether Isherwell's technology will be able to break apart the comet, angering the billionaire. Becoming frustrated with the administration, Mindy finally breaks down and rants on national television, criticizing Orlean for downplaying the impending apocalypse and questioning humanity's indifference.
Cut off from the administration, Mindy reconciles with Dibiasky as the comet becomes visible from Earth. Mindy, Dibiasky, and Oglethorpe organize a protest campaign on social media, telling people to "Just Look Up" and call on other countries to conduct comet interception operations. Simultaneously, Orlean starts an anti-campaign telling people "Don't Look Up". Orlean and BASH cut Russia, India, and China out of the rights for the comet-mining deal, so they prepare their own joint deflection mission, only for their spacecraft to explode. As the comet becomes larger in the sky, Orlean's supporters start turning on her administration. BASH's attempt at breaking the comet apart goes awry and everyone realizes that humanity is doomed.
Isherwell, Orlean, and others in their elite circle board a sleeper spaceship designed to find an Earth-like planet, inadvertently leaving Jason behind. Orlean offers Mindy two places on the ship, but he declines, choosing to spend a final evening with his friends and family. As expected, the comet strikes off the coast of Chile, causing a worldwide disaster and triggering an extinction-level event. In a mid-credits scene, the 2,000 people who left Earth before the comet's impact land on a lush alien planet 22,740 years later, ending their period of suspended animation. They exit their spacecraft naked and admire the habitable world. However, Orlean is suddenly killed by a bird-like predator (a death predicted by BASH's algorithms), one of a pack that surrounds the planetary newcomers. In a post-credits scene back on Earth, it is revealed that Jason managed to survive the impact. He records himself, declaring himself the "last man on Earth" and asking any viewers still alive to "like and subscribe".
Cast
Leonardo DiCaprio as Dr. Randall Mindy, an astronomy professor at Michigan State University (MSU) and Kate's teacher
Jennifer Lawrence as Kate Dibiasky, an MSU doctoral candidate in astronomy
Meryl Streep as Janie Orlean, the President of the United States
Cate Blanchett as Brie Evantee, co-host of The Daily Rip
Rob Morgan as Dr. Teddy Oglethorpe, head of the Planetary Defense Coordination Office
Jonah Hill as Jason Orlean, the White House Chief of Staff and President Orlean's son
Mark Rylance as Peter Isherwell, the billionaire CEO of the fictitious tech company BASH and one of Orlean's top donors
Tyler Perry as Jack Bremmer, the co-host of The Daily Rip
Timothée Chalamet as Yule, a young shoplifter whom Kate befriends
Ron Perlman as Colonel Benedict Drask, war veteran and Presidential Medal of Freedom recipient who is sent up with the initial launch to divert the comet
Ariana Grande as Riley Bina, an international pop music star
Kid Cudi (credited as his real name Scott Mescudi) as DJ Chello, an international rapper who becomes Riley's fiancé on The Daily Rip
Himesh Patel as Phillip Kaj, a journalist at Autopsy and Kate's boyfriend
Melanie Lynskey as June Mindy, Dr. Randall Mindy's wife
Michael Chiklis as Dan Pawketty, the host of the conservative Patriot News Network
Tomer Sisley as Adul Grelio, the senior editor at the New York Herald
Paul Guilfoyle as US Air Force Lieutenant General Stuart Themes, The Pentagon liaison to the White House
Robert Joy as Congressman Tenant, a congressman and follower of Janie
Other cast members include Kevin Craig West as the Secretary of State; Erik Parillo as Sheriff Conlon, Orlean's choice for Supreme Court Justice who ends up in a sex scandal with Orlean; Jon Glaser as Meow Man; Sarah Nolen as the puppeteer of Sammy; Allyn Burrows as Mr. Dibiasky, the father of Kate; and Tori Davis Lawlor as Mrs. Dibiasky, the mother of Kate.
Additionally, Robert Hurst Radochia and Conor Sweeney appear as Randall and June's sons, Evan and Marshall Mindy. Hettienne Park appears as Dr. Jocelyn Calder, the Administrator of NASA. Chris Everett appears as Paula Woods, chief editor at the New York Herald.
There are cameo appearances by Liev Schreiber as the BASH narrator, journalist Ashleigh Banfield as Dalia Hensfield, Sarah Silverman as comedian Sarah Benterman, Bollywood actor Ishaan Khatter as Raghav Manavalan, and Chris Evans in an uncredited role as film actor Devin Peters, who stars in the film Total Devastation.
Matthew Perry and Gina Gershon were cast for undisclosed roles in the film, but their scenes were cut.
Production
Produced by Hyperobject Industries and Bluegrass Films, the film was announced in November 2019 and sold by Paramount Pictures to Netflix several months later. Lawrence became the first member of the cast to join, with DiCaprio signing on after his discussions with McKay on adjustments to the script; the rest of the cast was added through 2020.
After Vice was released, David Sirota asked Adam McKay to use his "superpowers of humor and writing" to create a climate change movie that would be different from the Mad Max-type post-apocalyptic films that had previously been released. In an interview with Entertainment Weekly, McKay described how he and Sirota came up with the premise of Don't Look Up while discussing the existential threat of climate change and their frustration over the lack of media coverage it was receiving:
I started talking to a lot of [climate] scientists. I kept looking for good news, and I never got it. Everything I was hearing was worse than what I was hearing on the mainstream media. So I was talking to [David Sirota], and we were both just like, "can you believe that this isn't being covered in the media? That it's being pushed to the end of the story? That there's no headlines?" And Sirota just offhandedly said, "it's like a comet is heading to Earth and it's going to destroy us all and no one cares." And I was like, "that's the idea!"
McKay has described the film as a "blend of broad comedy" with elements of disaster films and horror films.
Astronomer Amy Mainzer, principal investigator of NASA's NEOWISE mission that tracks near-Earth objects, served as an "astrotech adviser" for the film. She provided scientific advice and supported with writing scenes from an early stage of production.
On November 8, 2019, it was announced that Paramount Pictures would distribute the film, with Adam McKay writing, directing, and producing under his Hyperobject Industries banner. On February 19, 2020, Netflix acquired the film from Paramount and Jennifer Lawrence was cast in the film. On May 12, 2020, it was announced that Cate Blanchett had joined the film. In September 2020, Rob Morgan joined the cast. In October 2020, Leonardo DiCaprio, Meryl Streep, Jonah Hill, Himesh Patel, Timothée Chalamet, Ariana Grande, Kid Cudi (Scott Mescudi), and Tomer Sisley were added. McKay wrote the part of Dibiasky specifically for Lawrence, and spent four to five months going over ideas with DiCaprio, tweaking the script before the actor ultimately signed on. In November 2020, Tyler Perry, Melanie Lynskey, and Ron Perlman joined the cast. Mark Rylance and Michael Chiklis were revealed as part of the cast in February 2021. Paul Guilfoyle was announced in May. Matthew Perry was also cast and had scenes filmed with Hill that were ultimately cut from the final film due to health issues. Gina Gershon also filmed a scene with DiCaprio and Blanchett that was cut from the film. Leonardo DiCaprio received top billing on the film's posters and the trailers while Jennifer Lawrence was accorded top billing at the beginning of the film itself. This was also the case with earlier productions The Man Who Shot Liberty Valance (1962) with James Stewart and John Wayne and All the President's Men (1976) with Robert Redford and Dustin Hoffman.
Principal photography was delayed due to the COVID-19 pandemic. Filming commenced on November 18, 2020, at various locations in Boston, Massachusetts. Part of the film takes place in New York City with Boston standing in as New York. Filming also took place in other Massachusetts cities including Brockton, Framingham, and Westborough. On February 5, 2021, Jennifer Lawrence was mildly injured during filming when a controlled glass explosion went awry. Filming wrapped on February 18, 2021.
Lawsuit
On December 6, 2023, Adam McKay, along with Netflix, was sued for copyright infringement over Don't Look Up. William Collier, an author from Baton Rouge, Louisiana, claimed that he is the original writer of the story, set in Baton Rouge, called "Stanley's Comet", which he self-published in 2012. Collier's daughter worked for Jimmer Miller Entertainment, part of McKay's management team until 2015. Collier alleges that his daughter submitted the text to Mosaic Media Group and it was then received by McKay's manager. "Since Stanley’s Comet was received by McKay’s manager, custom and practice in the entertainment industry dictates that this constitutes receipt by McKay," writes Steven Lowe, a lawyer for Collier, in the suit. "Furthermore, upon information and belief, the Novel was transmitted via courier, email or hand-delivery (or via other means) to McKay himself."
"The movie, like the novel, makes a strong political critique of the media, the government, and the cultural elite by showcasing their shallowness and reliance on popular opinion polls and social media algorithms," writes USC professor of comparative literature David Roman. "McKay’s film is also full of satire and humor and — like Stanley’s Comet — moves toward the absurd. In each case, the irony drives the humor and the social critique and does so in the same style and method."
Music
To promote the film, on December 3, 2021, Ariana Grande and Kid Cudi released the single "Just Look Up", which is also performed in the film. The original score for the film is composed by Nicholas Britell, who previously scored McKay's The Big Short (2015), Vice (2018) and the HBO television series Succession (2019–2022); McKay served as an executive producer of the latter. He used a wide range of instrumentation that reflect varied music styles and genres. He did this so as to give a remainder on the existential crisis on the planet following a catastrophic event as well as the absurdity of how people react to it. Apart from "Just Look Up", the film also featured "Second Nature" by Bon Iver, which was released along with Britell's score album on December 10, by Republic Records.
Reception
Box office and VoD
On February 19, 2020, it was announced that Netflix planned to release the film in 2020. Due to the COVID-19 pandemic, filming and release of the film were delayed. The film premiered in New York City on December 5, 2021. It received a limited theatrical release on December 10, and began streaming on Netflix on December 24. The film made an estimated $260,000 from 500 theaters on its first day, and a total of $700,000 in its opening weekend.
Don't Look Up was the most-streamed English-language film on Netflix during its first week of release with a viewership of 111.03 million hours, the second highest viewership for a movie during its debut weekend on Netflix. It was the second most-streamed-film of the week in the United States according to TV Time. Per Nielsen, the film had a viewership of 1.6 billion minutes in the United States. In the second week, it retained its first position with a viewership of 152.29 million hours, which also set the record for highest weekly viewership for any film ever on Netflix.
For its first 28 days, the film culminated a viewership of 359.8 million hours, making it the second most-watched film within 28 days of release on Netflix during this period of time. By March 20, the film had been streamed in 10.3 million households in the United States according to Samba TV, including 641,000 since the Oscar nomination announcements on February 8.
Critical response
The San Francisco Chronicle Mick LaSalle praised the film, "Don't Look Up might be the funniest movie of 2021. It's the most depressing too, and that odd combination makes for a one-of-a-kind experience. ... McKay gives you over two hours of laughs while convincing you that the world is coming to an end." Richard Roeper of the Chicago Sun-Times gave the film 2.5 out of 4 stars and said: "From Streep and DiCaprio and Lawrence through the supporting players, Don't Look Up is filled with greatly talented actors really and truly selling this material—but the volume remains at 11 throughout the story when some changes in tone here and there might have more effectively carried the day." In the Los Angeles Times, Justin Chang wrote, "Nothing about the foolishness and outrageousness of what the movie shows us—no matter how virtuosically sliced and diced by McKay's characteristically jittery editor, Hank Corwin—can really compete with the horrors of our real-world American idiocracy." Amit Katwala of Wired concluded that "Don't Look Up nails the frustration of being a scientist." Linda Marric of The Jewish Chronicle gave the film 4/5 stars, writing: "There is something genuinely endearing about a film that doesn't seem to care one bit about coming across as silly as long as its message is heard".
In a negative review, David Rooney of The Hollywood Reporter called it "A cynical, insufferably smug satire stuffed to the gills with stars that purports to comment on political and media inattention to the climate crisis but really just trivializes it. Dr. Strangelove it ain't." Peter Debruge of Variety called it a "smug, easy-target political satire" and wrote, "Don't Look Up plays like the leftie answer to Armageddon—which is to say, it ditches the Bruckheimer approach of assembling a bunch of blue-collar heroes to rocket out to space and nuke the approaching comet, opting instead to spotlight the apathy, incompetence and financial self-interest of all involved." In The Guardian, Charles Bramesco wrote that the "script states the obvious as if everyone else is too stupid to realize it and does so from a position of lofty superiority that would drive away any partisans who still need to be won over." In The Sociological Review, Katherine Cross accused the film of "smug condescension" and wrote it "is designed to flatter a certain type of liberal viewer into feeling like they're the last sane person in the world, surrounded by morons."
Reviews from right-wing publications were nearly unanimously negative. Madeline Fry Schultz of the American conservative publication Washington Examiner wrote "McKay manages to deliver nothing more than a derivative and meandering 'satire' of capitalism, Donald Trump, and climate deniers that will be forgotten in less than six months." Kyle Smith of the National Review wrote it "expends 140 brain-injuriously unfunny minutes... propelling low-velocity spitballs at social media, Washington, tech moguls, Trumpism, and (this detail feels thrown in last minute) anti-vaxxers."
Nathan J. Robinson, editor of American progressive publication Current Affairs, believes that "critics were not only missing the point of the film in important ways, but that the very way they discussed the film exemplified the problem that the film was trying to draw attention to. Some of the responses to the movie could have appeared in the movie itself." Slavoj Žižek, writing in Compact, said "critics were displeased by the light tone of Don't Look Up!, claiming it trivializes the ultimate apocalypse. What really bothered these critics is the exact opposite: The film highlights trivialization that permeates not only the establishment, but even the protesters." In The Guardian, Catherine Bennett viewed the film as astute and was caustic about the critical reviews. Journalist and environmental activist George Monbiot wrote that "no wonder journalists have slated it ... it's about them" and added that for environmental activists like himself, the film, while fastpaced and humorous, "seemed all too real". Author and activist Naomi Klein mentions it in her 2023 book Doppelganger: A Trip Into the Mirror World by saying that "Kate's plight perfectly mirrors the bizarre contradictions of our high-stakes moment in planetary history: we are all trapped inside economic and social structures that encourage us to obsessively perfect our miniscule selves even as we know, if only on a subconscious level, that we are in the very last years when it might still be possible to avert an existential planetary crisis."
Bong Joon-ho, director of Parasite, included Don't Look Up as one of his favorites of 2021.
Reception amongst scientists
Since the film's release, numerous climate scientists and climate communicators have offered positive opinions on the film.
In an opinion piece published in The Guardian, climate scientist Peter Kalmus remarked, "Don't Look Up is satire. But speaking as a climate scientist doing everything I can to wake people up and avoid planetary destruction, it's also the most accurate film about society's terrifying non-response to climate breakdown I've seen." Climate scientist Michael E. Mann also expressed support for the film, calling it "serious sociopolitical commentary posing as comedy". In an article for Scientific American, Rebecca Oppenheimer questioned the film's use of a comet impact as an effective metaphor for climate change, given the large differences in timescale of these differing potential extinction crisis events and the nature of their impacts, but praised its depiction of science denialism and depiction of a botched attempt to address a "planet-killer" comet. Climate policy expert Ayana Elizabeth Johnson and McKay wrote a joint op-ed in The Guardian advocating for the value of humour in promoting action on climate change, in contrast with other media coverage.
Writing in Physics World, Laura Hiscott said that this "genuinely funny and entertaining film" would appeal to scientists, who would appreciate the "nods to academia such as the importance of peer review, the 'publish or perish' problem and the issue of senior academics getting the credit for their PhD students' discoveries".
One of the scenes in the film was compared on social media to a situation in Brazil. In that situation, microbiologist and science communicator Natália Pasternak Taschner criticized a news report made by TV Cultura on a live broadcast in December 2020. They told the Brazilian population to face the COVID-19 pandemic with "lightness", minimizing the risks. They also put pressure on the public to be content and uncritical of the Jair Bolsonaro administration's lack of effective response to the pandemic. Hearing about the comparisons, Pasternak thanked McKay, DiCaprio and Lawrence on Twitter, with the video subtitled in English, for the "incredible" film.
Accolades
Analysis and themes
The topic of science communication is at the forefront of the film, as it revolves around Mindy and Dibiasky, two scientists, struggling to share the news of their discovery with politicians, talk show hosts, and civilians who are ignorant about the scientific facts of humanity's impending destruction by Comet Dibiasky. Many academic scholars of media and communication have written commentaries that analyze and critique the portrayal of science communication in the film.
U.S. centrism
In the Journal of Science Communication, Niels G. Mede writes "the film depicts sharp partisan divides, strong affective polarization, high distrust toward science within certain social milieus, and pronounced news media sensationalism, which have been found to be characteristic of the United States but not, or to a lesser extent, of several countries other than the US." From the same journal, writer Julie Doyle remarked that, "yet, as the film critiques existing structures and systems it does not imagine an alternative set of realities, nor explain the comet's cause. In focusing upon the fictional stories of scientists, politicians, and media celebrities, the film fails to center any marginalized voices, continuing to privilege global north perspectives, even as these are satirised." Doyle comments that "climate communication needs to keep in place both climate mitigation and adaptation, making the historical and structural inequalities of capitalism and colonialism the interconnected stories of both."
Media training for scientists
One solution to Mindy and Dibiasky's failed attempts to communicate the severity of the impending comet is undergoing media training, which was brought up in the film multiple times, such as at the conference room at the New York Herald where the Chief Editor proposes media training to Mindy before the show. The concept of media training can come in different forms. Samer Angelone, in a commentary journal on science communication, writes, "The style that scientists use to communicate science to peer scientists is mostly objective, complex, and full of technical jargon, which is difficult for the general public to connect to—even if it is in the same language." Another way to mitigate science skepticism is through storytelling. Mede writes, "The film also illustrates that storytelling can be a promising strategy to mitigate these reservations ... showing how Mindy is advised before a TV interview that he is 'just telling a story' and must 'keep it simple.'"
Gendered emotions in scientific communication
Gendered discourse on emotions and mental health make its way into the film through the portrayal of the public's reaction to Mindy and Dibiasky's various media appearances. The scientists share their discovery on a morning talk show, The Daily Rip, in which Dibiasky has an emotional outburst over the show hosts' persistent attempts to sugarcoat the devastating news of the doomsday comet. Professor of media and communication Julie Doyle writes, "Gendered norms affect Mindy and Dibiasky's public credibility and the mitigatory comet actions they promote. Following his own emotional outburst on TV, Mindy is subsequently recuperated through processes of celebritisation ... hailed as a 'sexy' scientist offering rational and calm advice to the viewers; becoming chief science advisor to the White House to monitor the drone activities of tech billionaire Peter Isherwell; and embarking on a sexual affair with Evantee. In contrast, Dibiasky is discredited and side-lined from rational public commentary through (climate) memes."
Easter eggs
Throughout the film, many historic figures from science and politics can be spotted, adding to the film's nuanced discussion about the relationship between science and politics.
The opening scene of the film features a figure of Carl Sagan on Dibiasky's desk. In a journal commentary for Science Communication, Samer Angelone writes that "Sagan was an astronomer, planetary scientist, cosmologist, astrophysicist, and astrobiologist but, above all, he was an upholder of scientific credibility and communication." Sagan advocated for the urgency to battle climate change, and many viewers see the film as an allegory for him, but his image is juxtaposed by a painting of George W. Bush, "who later tried to downplay this urgency." The film also "references the affinity of anti-science resentment and populism, showing how President Orlean and her team slander Mindy and Dibiasky using populist rhetoric ... and gather in an Oval Office that has a portrait of the anti-establishment science skeptic Andrew Jackson."
The film ends with a scene that reflects the Last Supper. Dr. Mindy, his family, Kate, Yule, and Teddy all sit around a dinner table and engage in a hand-held prayer, spoken by Yule. After the prayer, Kate Dibiasky gives Yule a kiss, and moments later Comet Dibiasky destroys Earth.
See also
Double Asteroid Redirection Test – a real NASA mission to test deflection of an asteroid in 2022
Climate change in popular culture
Notes
References
External links
Official screenplay
2020s English-language films
2020s American films
2020s satirical films
2020s political satire films
2021 films
2021 comedy films
English-language science fiction comedy films
Netflix original films
American science fiction comedy films
American survival films
Climate change films
Apocalyptic films
American disaster films
Fiction about comets
Films about American politics
Films about astronomy
Films about conspiracy theories
Films about impact events
Films directed by Adam McKay
Films with screenplays by Adam McKay
Films produced by Adam McKay
Films scored by Nicholas Britell
Films set in Illinois
Films set in Michigan
Films set in New York City
Films set in the White House
Films set in Washington, D.C.
Films shot in Boston
Films shot in Massachusetts
Film productions suspended due to the COVID-19 pandemic
Comets in film | Don't Look Up | [
"Astronomy"
] | 6,333 | [
"Films about astronomy",
"Works about astronomy"
] |
62,387,950 | https://en.wikipedia.org/wiki/Dimethyl%20chlorothiophosphate | Dimethyl chlorothiophosphate is a chemical that is used as an intermediate in the manufacture of pesticides and plasticisers. It is an organophosphate with sulfur and chlorine also bonded to the central phosphorus atom.
In 1985 American Cyanamid had an accidental release of this chemical from its Linden plant, and it was smelled 32 km away.
References
Organophosphates
Thiophosphoryl compounds | Dimethyl chlorothiophosphate | [
"Chemistry"
] | 94 | [
"Functional groups",
"Thiophosphoryl compounds"
] |
62,389,592 | https://en.wikipedia.org/wiki/Indentation%20size%20effect | The indentation size effect (ISE) is the observation that hardness tends to increase as the indent size decreases at small scales. When an indent (any small mark, but usually made with a special tool) is created during material testing, the hardness of the material is not constant. At the small scale, materials will actually be harder than at the macro-scale. For the conventional indentation size effect, the smaller the indentation, the larger the difference in hardness. The effect has been seen through nanoindentation and microindentation measurements at varying depths. Dislocations increase material hardness by increasing flow stress through dislocation blocking mechanisms. Materials contain statistically stored dislocations (SSD) which are created by homogeneous strain and are dependent upon the material and processing conditions. Geometrically necessary dislocations (GND) on the other hand are formed, in addition to the dislocations statistically present, to maintain continuity within the material.
These additional geometrically necessary dislocations (GND) further increase the flow stress in the material and therefore the measured hardness. Theory suggests that plastic flow is impacted by both strain and the size of the strain gradient experienced in the material. Smaller indents have higher strain gradients relative to the size of the plastic zone and therefore have a higher measured hardness in some materials.
For practical purposes this effect means that hardness in the low micro and nano regimes cannot be directly compared if measured using different loads. However, the benefit of this effect is that it can be used to measure the effects of strain gradients on plasticity. Several new plasticity models have been developed using data from indentation size effect studies, which can be applied to high strain gradient situations such as thin films.
References
Hardness tests
Materials science
Plasticity (physics) | Indentation size effect | [
"Physics",
"Materials_science",
"Engineering"
] | 368 | [
"Applied and interdisciplinary physics",
"Deformation (mechanics)",
"Materials science",
"Plasticity (physics)",
"Materials testing",
"nan",
"Hardness tests"
] |
62,391,803 | https://en.wikipedia.org/wiki/Trusted%20Shops | Trusted Shops is a company founded in Cologne, Germany in 1999, which offers online shops and their customers trust-building services by means of a trustmark, a money-back guarantee process and a system of customer reviews. Online retailers are also provided with assistance in meeting legal requirements. Around 25,000 online shops display the trustmark as of July 2019.
Company history
Foundation
The company was founded in Cologne (Germany) in 1999 as a joint venture between Gerling Speziale Kreditversicherungs AG and the business consultancy Impact Business & Technology Consulting GmbH. Jean-Marc Noël and Ulrich Hafenbradl were among the founders. The company began operations one year later. Its offer consisted of a trustmark for online shops, and from the very beginning the company also offered customers of online shops displaying the trustmark a money-back guarantee. By mid-November 2000, around 100 shops had obtained the trustmark.
Development
The number of online shops with a trustmark grew in the following years. While there were 9,000 in 2010, more than 30,000 trusted shops are currently registered (last update October 2021).
In 2009, the company offered interested shops its web-based shopping review tool as a stand-alone version that is independent of the trustmark.
Trusted Shops France SARL was founded in 2017 as a wholly owned subsidiary of Trusted Shops GmbH, and one year later the Polish subsidiary was founded. The Spanish subsidiary was founded in September 2019 and the Dutch subsidiary in October 2019.
Present
Services
Online shops are entitled to use the Trusted Shops trustmark after passing an audit that includes aspects such as data security, consumer protection, customer service, price transparency and creditworthiness.
The money-back guarantee adds financial security to the promise that online shops with trustmark are trustworthy providers.
Companies can use web-based feedback systems to have their customers review purchases or transactions. This includes, for example, the service, the website, or the delivered product quality. The system ensures that only customers who have made purchases participate in the feedback procedure.
The legal security aid is offered in cooperation with law firms and includes, among other things, the drafting of legal texts (such as the General Terms and Conditions), checking websites for compliance with e-commerce law, and representation in case of legal disputes in Germany and other European countries.
Personnel and locations
The company’s headquarters is located in Cologne (Germany). Further locations are in France (Lille), in the Netherlands (Amsterdam), in Poland (Warsaw) and in Spain (Barcelona). According to its own statements, the company employs 500 people.
Owners
According to the information based on the financial year 2017 provided by Bisnode, two Crédit Agricole funds (CA Innovation 10 and LCL Innovation 2009) jointly own 10% of the shares in Trusted Shops. Two private equity and infrastructure funds owned by French investor Omnes Capital (Capital Invest PME 2014 and Capital Invest PME 2015) jointly hold 4%. Sohano GmbH owns 23% and Entract GmbH owns 38%. 25% is held by Global Founders Capital GmbH & Co (belongs to Rocket Internet).
References
Certification marks
E-commerce
Companies based in Cologne
1999 establishments in Germany | Trusted Shops | [
"Mathematics",
"Technology"
] | 652 | [
"E-commerce",
"Information technology",
"Symbols",
"Certification marks"
] |
62,392,383 | https://en.wikipedia.org/wiki/Microsoft%20SEAL | Simple Encrypted Arithmetic Library or SEAL is a free and open-source cross platform software library developed by Microsoft Research that implements various forms of homomorphic encryption.
History
Development originally came out of the Cryptonets paper, demonstrating that artificial intelligence algorithms could be run on homomorphically encrypted data.
It is open-source (under the MIT License) and written in standard C++ without external dependencies and so it can be compiled cross platform. An official .NET wrapper written in C# is available and makes it easier for .NET applications to interact with SEAL.
Features
Algorithms
Microsoft SEAL supports both asymmetric and symmetric (added in version 3.4) encryption algorithms.
Scheme types
Microsoft SEAL comes with two different homomorphic encryption schemes with very different properties:
BFV: The BFV scheme allows modular arithmetic to be performed on encrypted integers. For applications where exact values are necessary, the BFV scheme is the only choice.
CKKS: The CKKS scheme allows additions and multiplications on encrypted real or complex numbers, but yields only approximate results. In applications such as summing up encrypted real numbers, evaluating machine learning models on encrypted data, or computing distances of encrypted locations CKKS is going to be by far the best choice.
Compression
Data compression can be achieved by building SEAL with Zlib support. By default, data is compressed using the DEFLATE algorithm which achieves significant memory footprint savings when serializing objects such as encryption parameters, ciphertexts, plaintexts, and all available keys: Public, Secret, Relin (relinearization), and Galois. Compression can always be disabled.
Availability
There are several known ports of SEAL to other languages in active development:
C++
Microsoft SEAL (Microsoft's source)
C#/F#
NuGet (Microsoft's official package)
Python
PySEAL
SEAL-Python
tf-seal
Pyfhel
JavaScript
node-seal
sealjs
TypeScript
node-seal
References
External links
Homomorphic encryption
Cryptographic software
Free and open-source software
SEAL
Microsoft Research
Free software programmed in C++
Software using the MIT license
2018 software | Microsoft SEAL | [
"Mathematics"
] | 447 | [
"Cryptographic software",
"Mathematical software"
] |
58,044,999 | https://en.wikipedia.org/wiki/Cast-in-place%20concrete | Cast-in-place concrete or Cast-in-situ concrete is a technology of construction of buildings where walls and slabs of the buildings are cast at the site in formwork. This differs from precast concrete technology where slabs are cast elsewhere and then brought to the construction site and assembled. It uses concrete slabs for walls instead of bricks or wooden panels, and formwork is used for both walls and roof.
Advantages of this technology are strength of the building, insulation, and versatility for different types of buildings. A disadvantage is the high amount of labor required to install and remove formwork.
See also
Precast concrete
Formwork
References
Building engineering | Cast-in-place concrete | [
"Engineering"
] | 131 | [
"Building engineering",
"Civil engineering",
"Civil engineering stubs",
"Architecture"
] |
58,045,840 | https://en.wikipedia.org/wiki/Rebecca%20Goss%20%28chemist%29 | Rebecca Jane Miriam Goss is a British organic chemist and professor at the University of St. Andrews recognized for her contributions to discovering and engineering biosynthesis of natural products, particularly anti-infectives, through the integration of synthetic biology and chemistry. Among other achievements and awards, Dr. Goss won the 2006 Royal Society of Chemistry Meldola Medal.
Early life and education
Goss completed her undergraduate studies in Chemistry at Hatfield College in the University of Durham in 1997, during which she earned the distinction of graduating with honors. Goss remained at the University of Durham to complete her Ph.D. under the supervision of Professor David O'Hagan. She was awarded the Ph.D. in 2001 after studying the stereochemistry of biosynthetic pathways during the formation of various natural products, specifically the enzyme-catalyzed reaction to produce fluoroacetate through fluorination.
Research and Career
Goss specializes in the biosynthesis of natural products at the chemical and genetic level.
Goss joined the University of Cambridge in 2000 to study the chemistry and molecular biology of polyketide biosynthesis in the research group of Professors Jim Staunton (FRS) and Peter Leadlay (FRS). She held a one-year teaching fellowship at the School of Chemistry, University of Nottingham between 2002 and 2003 before obtaining a lectureship at the School of Biological and Chemical Science, University of Exeter in 2003. Between 2005 and 2010, Goss held a lectureship at the University of East Anglia before being promoted to senior lecturer in 2010 and then reader in organic chemistry in 2012. Goss moved to the University of St. Andrews in 2012 to become a reader in biomolecular and organic chemistry. In 2018, she became the first woman to be appointed a full professor of organic chemistry in St Andrews' 600-year history.
Through her professorship in Biomolecular/Organic Chemistry at the University of St. Andrews, Dr. Goss leads the Goss group, which leads a series of projects working on an array of projects within the field of chemical biology, with natural products as the central focus. One of the key concepts developed by the group is GenoChemetics, which is a unique paradigm in natural product analog generation. This represents a revolutionary approach that combines synthetic biology and synthetic chemistry to address challenges encountered by synthetic chemists. Chemically-active motifs within natural products often pose difficulties, leading to side reactions during synthesis. Traditional approaches involve extensive protection of sensitive functionality through protecting groups or avoidance of introducing such motifs until the final stages of synthesis. In contrast, GenoChemetics employs synthetic biology to engineer chemically orthogonal and reactive functionality directly into natural products.
This innovative approach selectively introduces reactive functional handles into specific sites within natural products through the integration of foreign genes into the microorganisms responsible for natural product synthesis, alongside existing biosynthetic processes, and the group is able to activate the core structures of natural products. This activation allows for targeted modification of the natural product core through diverse reactions, leading to the creation of novel analogs with enhanced properties. The Goss Group's research in GenoChemetics marks a significant advancement in natural product synthesis, opening up new avenues for designing and developing bioactive compounds with therapeutic potential.
She was awarded the Royal Society of Chemistry Meldola prize for her work to understand the interface of organic chemistry and molecular biology. In 2013 she was awarded the Royal Society of Chemistry Natural Product Report Emerging Researcher Lectureship for her pioneering approach to 'Genochemetics', which combines synthetic biology and chemistry for medicinal purposes. In 2014 she was awarded an ERC consolidator grant.
Goss is on the advisory board for the peer-reviewed journals Chemical Communications and Natural Product Reports.
Awards
2013 Royal Society of Chemistry Natural Product Report Lectureship Award
2011 UK's under 40 Organic Chemistry delegate for EuCheM’s Young Investigators Workshop
2011 Thieme Chemistry Journal Award
2006 Royal Society of Chemistry - Meldola prize
References
External links
Living people
British women chemists
British chemists
British organic chemists
Year of birth missing (living people)
Place of birth missing (living people)
Academics of the University of St Andrews
Alumni of Hatfield College, Durham
Academics of the University of Nottingham
Academics of the University of Exeter
Academics of the University of East Anglia | Rebecca Goss (chemist) | [
"Chemistry"
] | 875 | [
"Organic chemists",
"British organic chemists"
] |
58,046,455 | https://en.wikipedia.org/wiki/Kawai%20Q-80 | The Kawai Q-80 by Kawai Musical Instruments in 1989, is a music sequencer that has a built in 2DD floppy disk drive for storage. It allows playback, editing, and recording via its MIDI connections. There is a battery backup to hold the configuration when the unit is powered down. The tempo can be set from 40-250 beats per minute.
Active quantisation
Only corrects the notes that are completely out of time with the rest of the track, for a more natural feel and less robotic to the performance.
Connections
MIDI in, out and Thru.
Tape sync in and out
Metronome
Footswitch input
Storage
Using the units internal S-RAM the Q-80 can hold;
A total of 26,000 notes, this consists of 10 songs (up to 32 tracks, 15,000 notes per track)
100 motifs per song (similar to a pattern in a drum machine)
References
External links
Owners manual
https://drive.google.com/file/d/0B3OQk-sD72jXN3UwUF9tNGF6UmM/view
Kawai synthesizers
Music sequencers
Products introduced in 1989 | Kawai Q-80 | [
"Engineering"
] | 239 | [
"Music sequencers",
"Automation"
] |
58,046,842 | https://en.wikipedia.org/wiki/Frontier%20Radio | The Frontier Radio is a family of software-defined radios developed by the Johns Hopkins University Applied Physics Laboratory (or APL). Four variants have been developed: the Frontier Radio (FR), the Frontier Radio Lite (FR Lite), and the Frontier Radio Multi Lingual (FR ML), and the Next-Gen Frontier Radio. In addition, the Frontier-S and Frontier-X are licensed derivatives manufactured by commercial aerospace company Rocket Lab.
History
Parents and predecessors
The creation of the FR family was predated by the transceivers built for the New Horizons, TIMED, and CONTOUR spacecraft, all of which required lightweight transceivers with low power consumption. These efforts were successful; for example, the transceiver for New Horizons managed to save 12 W from total mission power and ended up being a mission-enabler. Based on results from these missions, APL sought an opportunity to build a general-purpose radio with even lower SWaP (Size, Weight, and Power) as a software-defined radio (SDR) platform usable by any aerospace organization. The SDR platform would accommodate transceivers with higher data-rate return link capabilities and better radiation tolerance than previous radios. APL brought the idea before NASA, who approved further research.
Frontier Radio history
The first iteration of the Frontier Radio (FR) to fly was on the near space Van Allen Probes (VAP) mission. It was used because of its high radiation tolerance, low SWaP, and long lifetime. A deep space version of the FR flew on the Parker Solar Probe (PSP) mission in 2018. This version was modified for the PSP mission with updates such as software enhancements to improve downlink frame rates, RF hardware to operate at the higher frequency X and Ka bands, and hardware enhancements to increase processing capacity. The FR also flew on NASA's Double Asteroid Redirection Test (DART) missions, where it featured improvements such as support for higher data rates at X-Band.
Other missions needed radios with less size, mass, and power consumption, and did not require the full robustness of FR. This led to the development of Frontier Radio Lite, a much smaller radio for resource-constrained missions. The biggest change was a reduction in the maximum data rates and the signal sensitivity, allowing a lower power consumption, while some radiation tolerance was sacrificed to achieve better size, weight, and power. Next came the Frontier Radio Virtual Radio, intermediate between the FR and the FR Lite. It combines the robust nature and processing power of the original radio with a reprogrammable design and more modern architecture used by the FR Lite.
Versions
Heritage Frontier Radio
Following the launch of the New Horizons mission and its low SWaP radio, NASA funded more research into other small, highly reliable radio products for future missions by APL, this time utilizing software-defined platforms. The grant led to the creation of the heritage Frontier Radio (FR), built for near and deep space applications.
Types
The heritage FR has two main versions: a near space radio that operates at S-band, as used on the VAP mission, and a deep space version that operates at X/Ka-band, as used on the PSP mission. Both versions use the same core infrastructure with some improvements over the first version that flew on VAP. These include reduction of SWaP, improved robustness, lower noise, higher speed signal conversion and processing, and better signal acquisition and tracking.
Key features
The FR has a separate interface board so that the hardware can be customized to each mission without having to build a brand new radio. Certain features can also be reconfigured in flight, like in-band channel assignment, bit rate, loop bandwidths, and coding formats, and modulation schemes. Its circuits are designed to be highly reliable and fault tolerant, taking into account vacuum, high radiation, and extreme temperature environments. It can withstand total ionizing doses (TID) of up to 100 krad (1 kGy) and has single event latch-up (SEL, or a latch-up caused by a single event upset) immunity of 85 MeV-cm2/mg of linear energy transfer (LET).
Limitations
The FR is not reprogrammable. It is also the physically largest radio in the family.
Frontier Radio Lite
The Frontier Radio Lite is the smaller version of its sibling, the Frontier Radio, fitting all of its systems onto a single card. Originally an S-band radio, FR Lite was the first in the family to be reprogrammable, and is designed for missions with high risk tolerance and quick schedules. It is the lowest SWaP radio in the Frontier family, making it ideal for small-sat and cube-sat missions.
Types
Two versions of FR Lite have been designed and built. The first is a two-way radio operating at S-band, and the second is a L-band receiver for GPS L1 & L2, renamed the Extensible Global Navigation System (EGNS). The S-band version of this radio has been transferred to industry and can be purchased from Rocket Lab under the name Frontier-S.
Key features
The FR Lite uses a reprogrammable field-programmable gate array (FPGA) instead of a dedicated Application Specific Integrated Circuit (ASIC), greatly decreasing development cost and allowing increased flexibility. Its mass and volume are less than 25% of the FR's, and its receive and transmit modes use less than 30% of the total FR power. These improvements were accomplished by moving a number of analog hardware sections into firmware, sharing components of the circuit for the up and down conversions of frequencies, improved power regulation design, and a number of smaller changes.
Limitations
The FR Lite sacrifices some of its radiation tolerance and SEL immunity in order to achieve its low SWaP; it can only withstand TID of 40 krads and has a 20% reduction in SEL immunity compared to the FR.
Frontier Radio Multi Lingual
The Frontier Radio Multi Lingual (FR ML) is the newest addition to the FR family, and the first specifically targeting high throughput applications. With receive and transmit throughputs greater than 1 GBPs, FR ML was developed at the direction of NASA's Space Communications and Navigation Program, meant as a first step to replace the aging Tracking and Data Relay Satellite System (TDRSS) constellation. The radio is designed to operate in commercial, military, and science allocated Ka-bands, hence the multi-lingual nature of the design.
Types
The FR ML currently comes in one version, with Ka up- and down-conversion.
Key features
The FR ML features a more advanced FPGA than previous FR variants, allowing support for DBV-S2, OFDMA, and CCSDS waveforms. Improvements in processing power, predistortion, and RF front end linearity enable support of uplink and downlink data rates in excess of 1 GBps. The radio is tolerant to 100 krad TID and single event effect immunity to 72 MeV-cm2/mg. A supervisor co-processor also enables complete in-flight reportability, of not just software but firmware as well.
Limitations
High power consumption limits FR ML usage on some small-sat missions.
Next Generation Frontier Radio
The Next Generation Frontier Radio is currently under development and aims to create the next generation deep space and near earth SDR platform. This platform seeks to combine the high reliability of the heritage FR with the low SWaP of FR Lite and the high performance of FR ML. This is accomplished via novel configurability of a deep space radio platform. Featuring both a high performance FPGA and co-processor, these computing capabilities can be scaled through component level variants to support both high performance FR ML applications and low power deep space applications on the same underlying architecture. This means that the same hardware, with component reconfigurations, can support GBps links in one mission, and sub-1W receive links in another. Like FR ML, the radio is tolerant to 100 krad TID and single event effect immunity to 72 MeV-cm2/mg.
Support for swappable and multiple RF front ends is also a key enabler of flexibility of NG-FR. RF front ends supporting this next-gen architecture at C/X/Ku and well as Ka bands have been developed. Future work on L/S-bands, VHF/UHF, and a low power NASA Deep Space Network front end are all in development as of May 2023. The first mission slated to fly this new architecture is NASA's DAVINCI mission to Venus.
Frontier-S and Frontier-X
The Frontier-S and Frontier-X are a variants of the Frontier Radio Lite manufactured by United States-based aerospace company Rocket Lab, who licensed the design in 2021 for commercial use. Currently, the Frontier-S has flown on Rocket Lab's Photon Pathstone spacecraft, launched in March 2021, on the Photon spacecraft used for the CAPSTONE mission in March 2022 as well as a private mission to Venus. Rocket Lab also produces a "deep-space" variant with additional features.
The Frontier-X is an X-band version of the FR Lite, designed and licensed specifically for Rocket Lab. It will be first flown on the upcoming NASA SIMPLEx mission to Mars EscaPADE
Comparison
*Bare slices only; total volume/mass depends on packaging.
†Frontier Radio & FR VR numbers include an ovenized oscillator and +28V bus power converter unit with ~1.4-W quiescent draw and ~80% efficiency vs. a lower-power TCXO and lower-voltage 6-12V bus power on FR Lite.
‡Two transmit channels switchable but not simultaneous.
Current and future missions
FR radios have flown on various Cubesat missions. An L-band version of FR Lite (EGNS) flew on a Cubesat mission in 2019. Also, a version of the FR VR with S-band receive and transmit (with L-band receive as well) was scheduled to fly on a JHU/APL Cubesat mission in 2022.
The Emirates Mars Mission HOPE uses a FR transponder.
The Europa Clipper mission will use an FR transponder both for communication and gravity science.
Another mission that may use a member of the FR family is the proposed Europa Lander. In order to determine if Europa, one of Jupiter's smaller moons, is holding a liquid ocean beneath a layer of ice and could support life, NASA is investigating sending a lander to the surface of the moon. The current plan for the radio is for the Europa Lander and its Carrier and Relay Stage (CRS) to use a version of the heritage FR with added X-band functionality for cross-band uplink and downlink. The FR will also fly on NASA's Interstellar Mapping and Acceleration Probe to study to heliosphere as well as the NASA New Frontiers Dragonfly (Titan space probe) mission set to launch in 2027.
See also
Electra (radio) - A UHF transponder for satellite to surface communication
Small Deep Space Transponder - another small spacecraft transponder designed by JPL and produced by General Dynamics.
Iris (transponder) - a transponder smaller than SDST developed by JPL for use in cubesats
References
Software-defined radio | Frontier Radio | [
"Engineering"
] | 2,337 | [
"Radio electronics",
"Software-defined radio"
] |
58,047,066 | https://en.wikipedia.org/wiki/Periodic%20lateralized%20epileptiform%20discharges | Periodic lateralized epileptiform discharges are a type of EEG abnormality. They are one of the most frequent paroxystic complexes. They are basically triphasic with sharply contoured wave followed by a slow wave mostly occurring unilaterally with duration 100-300 msec and amplitude 100-300 often present with fast rhythm between discharges. In recent literature it is referred to as Lateralized periodic discharges.
References
Electroencephalography
Neuroscience | Periodic lateralized epileptiform discharges | [
"Biology"
] | 98 | [
"Neuroscience"
] |
58,051,488 | https://en.wikipedia.org/wiki/Choong%20Eui%20Song | Choong Eui Song (; born January 15, 1955) is a South Korean organic chemist.
Biography
Song was born and raised in Seoul. He received his B.S. degree from Chung-Ang University in 1980, and received a diploma (1985) and a Ph.D. (1988) at RWTH Aachen University in Germany.
After completing his Ph.D., he worked as Principal Research Scientist at the Korea Institute of Science and Technology (KIST). In 2001, he was appointed as a head of the National Research Laboratory for Green Chirotechnology in Korea. In 2004, he moved to Sungkyunkwan University (Department of Chemistry) as a full professor. In 2005, he was elected as the vice-president of Korean Chemical Society. From 2006 to 2014 he worked as a director at the Research Institute of Advanced Nanomaterials (University-centered Lab, Korea Research Foundation). In 2016 he was appointed as a director of National Research Laboratory for Chiral Organic Molecular Materials in Korea.
He has been visiting professors for several universities/institutes in the worlds, including:
Max-Planck-Institut fuer Kohlenforschung, Mülheim, Germany, 2010
University of Southampton, England, 2015
He served as a technical advisor to the Samsung Advanced Institute of Technology, Dongwoo Fine-Chem and Hansol Chemical. He has been a board member of Kyongbo Pharmaceuticals s since 2015.
His research has been focused on asymmetric organocatalysis, biomimetic catalysis, artificial enzyme, on-water catalysis and on-droplet catalysis. His current research also focuses on prebiotic chemistry, specifically, the origin of homochirality (chirality amplification process).
Honors and awards
He has received several scientific awards including:
The Korean 52 Research Scientists (Ministry of Science and Technology (South Korea), 1998)
The Scientist of the Month Award (Korea Institute of Science and Technology, 2000)
The Scientist of the Month Award of Korea (Ministry of Science and Technology (South Korea), 2001)
The distinguished contribution award for new drug development (Korea Drug Research Association, 2004)
Academic Excellence Grand Prize (Korean Chemical Society, 2013)
Academic Excellence Grand Prize Korean Society of Organic Synthesis, 2017)
In 2018, he was elected to the Korean Academy of Science and Technology.
References
1955 births
Living people
Chung-Ang University alumni
RWTH Aachen University alumni
Academic staff of Sungkyunkwan University
South Korean organic chemists | Choong Eui Song | [
"Chemistry"
] | 513 | [
"South Korean organic chemists",
"Organic chemists"
] |
58,051,627 | https://en.wikipedia.org/wiki/Maria%20de%20F%C3%A1tima%20Agra | Maria de Fátima Agra (born 1952) is a Brazilian botanist and associate professor at the Universidade Federal da Paraíba (UFPB), in João Pessoa, Paraíba, Brazil. Agra specializes in ethnobotany, pharmacognosy, and plant morphology, particularly pertaining to plants of the family Solanaceae in northeastern Brazil.
Biography
Agra earned an undergraduate degree in Pharmaceutical Sciences from the Federal University of Paraíba (1977), a master's degree in botany from the Federal University of Pernambuco (1991), and a doctorate in Biological Sciences (specializing in botany) from the University of São Paulo (2001). She chairs the Postgraduate Program in Natural Products and Bioactive Synthetics at the UFPB. She is a founding editor of the Revista UNIPLAC and a member of the Botanical Society of Brazil (Sociedade Botânica do Brasil), of which she served as vice president in 2001.
Agra has published and served as a peer reviewer extensively in various languages, including the scholarly journals Rodriguésia, Novon, Journal of Ethnopharmacology, Annals of Tropical Medicine & Parasitology, Pharmaceutical Biology, and the European Journal of Pharmacology. According to Google Scholar, Agra's h-index is 32, and researchers have cited her work more than 5,100 times.
Under the author abbreviation "Agra," she has described sixteen plant species.
References
External links
Institutional profile
20th-century Brazilian botanists
21st-century Brazilian women scientists
Brazilian women academics
Living people
Brazilian women botanists
21st-century Brazilian botanists
Taxon authorities
Ethnobotanists
1952 births
Academic staff of the Federal University of Paraíba | Maria de Fátima Agra | [
"Biology"
] | 346 | [
"Taxon authorities",
"Taxonomy (biology)"
] |
58,052,112 | https://en.wikipedia.org/wiki/Pparg%20coactivator%201%20alpha | Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) is a protein that in humans is encoded by the PPARGC1A gene. PPARGC1A is also known as human accelerated region 20 (HAR20). It may, therefore, have played a key role in differentiating humans from apes.
PGC-1α is the master regulator of mitochondrial biogenesis. PGC-1α is also the primary regulator of liver gluconeogenesis, inducing increased gene expression for gluconeogenesis.
Function
PGC-1α is a gene that contains two promoters, and has 4 alternative splicings. PGC-1α is a transcriptional coactivator that regulates the genes involved in energy metabolism. It is the master regulator of mitochondrial biogenesis. This protein interacts with the nuclear receptor PPAR-γ, which permits the interaction of this protein with multiple transcription factors. This protein can interact with, and regulate the activity of, cAMP response element-binding protein (CREB) and nuclear respiratory factors (NRFs) . PGC-1α provides a direct link between external physiological stimuli and the regulation of mitochondrial biogenesis, and is a major factor causing slow-twitch rather than fast-twitch muscle fiber types.
Endurance exercise has been shown to activate the PGC-1α gene in human skeletal muscle. Exercise-induced PGC-1α in skeletal muscle increases autophagy and unfolded protein response.
PGC-1α protein may also be involved in controlling blood pressure, regulating cellular cholesterol homeostasis, and the development of obesity.
Regulation
PGC-1α is thought to be a master integrator of external signals. It is known to be activated by a host of factors, including:
Reactive oxygen species and reactive nitrogen species, both formed endogenously in the cell as by-products of metabolism but upregulated during times of cellular stress.
Fasting can also increase gluconeogenic gene expression, including hepatic PGC-1α.
It is strongly induced by cold exposure, linking this environmental stimulus to adaptive thermogenesis.
It is induced by endurance exercise and recent research has shown that PGC-1α determines lactate metabolism, thus preventing high lactate levels in endurance athletes and making lactate as an energy source more efficient.
cAMP response element-binding (CREB) proteins, activated by an increase in cAMP following external cellular signals.
Protein kinase B (Akt) is thought to downregulate PGC-1α, but upregulate its downstream effectors, NRF1 and NRF2. Akt itself is activated by PIP3, often upregulated by PI3K after G protein signals. The Akt family is also known to activate pro-survival signals as well as metabolic activation.
SIRT1 binds and activates PGC-1α through deacetylation inducing gluconeogenesis without affecting mitochondrial biogenesis.
PGC-1α has been shown to exert positive feedback circuits on some of its upstream regulators:
PGC-1α increases Akt (PKB) and Phospho-Akt (Ser 473 and Thr 308) levels in muscle.
PGC-1α leads to calcineurin activation.
Akt and calcineurin are both activators of NF-kappa-B (p65). Through their activation, PGC-1α seems to activate NF-kappa-B. Increased activity of NF-kappa-B in muscle has recently been demonstrated following induction of PGC-1α. The finding seems to be controversial. Other groups found that PGC-1s inhibit NF-kappa-B activity. The effect was demonstrated for PGC-1 alpha and beta.
PGC-1α has also been shown to drive NAD biosynthesis to play a large role in renal protection in acute kidney injury.
Clinical significance
PPARGC1A has been implicated as a potential therapy for Parkinson's disease conferring protective effects on mitochondrial metabolism.
Moreover, brain-specific isoforms of PGC-1alpha have recently been identified which are likely to play a role in other neurodegenerative disorders such as Huntington's disease and amyotrophic lateral sclerosis.
Massage therapy appears to increase the amount of PGC-1α, which leads to the production of new mitochondria.
PGC-1α and beta has furthermore been implicated in polarization to anti-inflammatory M2 macrophages by interaction with PPAR-γ with upstream activation of STAT6. An independent study confirmed the effect of PGC-1 on polarisation of macrophages towards M2 via STAT6/PPAR gamma and furthermore demonstrated that PGC-1 inhibits proinflammatory cytokine production.
PGC-1α has been recently proposed to be responsible for β-aminoisobutyric acid secretion by exercising muscles. The effect of β-aminoisobutyric acid in white fat includes the activation of thermogenic genes that prompt the browning of white adipose tissue and the consequent increase of background metabolism. Hence, the β-aminoisobutyric acid could act as a messenger molecule of PGC-1α and explain the effects of PGC-1α increase in other tissues such as white fat.
PGC-1α increases BNP expression by coactivating Estrogen-related receptor alpha (ERRα) and / or AP1. Subsequently, BNP induces a chemokine cocktail in muscle fibers and activates macrophages in a local paracrine manner, which can then contribute to enhancing the repair and regeneration potential of trained muscles.
Most studies reporting effects of PGC-1α on physiological functions have used mouse models in which the PGC-1α gene is either knocked out or overexpressed from conception. However, some of the proposed effects of PGC-1α have been questioned by studies using inducible knockout technology to remove the PGC-1α gene only in adult mice. For example, two independent studies have shown that adult expression of PGC-1α is not required for improved mitochondrial function after exercise training. This suggests that some of the reported effects of PGC-1α are likely to occur only in the developmental stage.
In the metabolic disorder of combined malonic and methylmalonic aciduria (CMAMMA) due to ACSF3 deficiency, there is a massively increased expression of PGC-1α, which is consistent with upregulated beta oxidation.
Interactions
PPARGC1A has been shown to interact with:
CREB-binding protein
Estrogen-related receptor alpha (ERRα), estrogen-related receptor beta (ERR-β), estrogen-related receptor gamma (ERR-γ).
Farnesoid X receptor
FBXW7
MED1, MED12, MED14, MED17,
NRF1
Peroxisome proliferator-activated receptor gamma
Retinoid X receptor alpha
Thyroid hormone receptor beta
ERRα and PGC-1α are coactivators of both glucokinase (GK) and SIRT3, binding to an ERRE element in the GK and SIRT3 promoters.
See also
MB-3 (drug)
PPARGC1B
Transcription coregulator
References
Further reading
External links
Exercise biochemistry | Pparg coactivator 1 alpha | [
"Chemistry",
"Biology"
] | 1,544 | [
"Biochemistry",
"Exercise biochemistry"
] |
58,053,955 | https://en.wikipedia.org/wiki/Augmented%20Reality%20Sandtable | The Augmented Reality Sandtable (ARES) is an interactive, digital sand table that uses augmented reality (AR) technology to create a 3D battlespace map. It was developed by the Human Research and Engineering Directorate (HRED) at the Army Research Laboratory (ARL) to combine the positive aspects of traditional military sand tables with the latest digital technologies to better support soldier training and offer new possibilities of learning. It uses a projector to display a topographical map on top of the sand in a regular sandbox as well as a motion sensor that keeps track of changes in the layout of the sand to appropriately adjust the computer-generated terrain display.
An ARL study conducted in 2017 with 52 active duty military personnel (36 males and 16 females) found that the participants who used ARES spent less time setting up the table compared to participants who used a traditional sand table. In addition, ARES demonstrated a lower perceived workload score, as measured using the NASA Task Load Index (NASA-TLX) ratings, compared to the traditional sand table. However, there was no significant difference in post-knowledge test scores in recreating the visual map.
Development
The ARES project was one of the 25 ARL initiatives in development from 1995 to 2015 that focused on visualizing spatial data on virtual or sand table interfaces. It was developed by HRED's Simulation and Training Technology Center (STTC) with Charles Amburn as the principal investigator. Collaborations involved with ARES included Dignitas Technologies, Design Interactive (DI), the University of Central Florida's Institute for Simulation and Training, and the U.S. Military Academy at West Point.
ARES was largely designed to be a tangible user interface (TUI), in which digital information can be manipulated using physical objects such as a person's hand. It was constructed using commercial off-the-shelf components, including a projector, a laptop, an LCD monitor, Microsoft's Xbox Kinect sensor, and government-developed ARES software. With the projector and Kinect sensor both facing down on the surface of the sandbox, the projector provides a digital overlay over the sand and the Kinect sensor scans the surface of the map to detect any user gestures inside the boundaries of the sandbox.
During development, researchers explored the possibility of incorporating ideas such as multi-touch surfaces, 3D holographic displays, and virtual environments. However, budget restrictions limited the implementation of such ideas.
In September 2014 during the Modern Day Marine exhibition in Quantico, Virginia, researchers from ARL showcased ARES for the first time.
Uses
According to a 2015 technical report by ARL scientists, ARES is reported to have the following capabilities.
Images, maps, and videos can be projected into the sand table from a top-down point of view in real time.
Terrain and scenarios created in ARES can be imported into different simulation applications, such as Virtual Battlespace 3 (VBS3) and One Semi-Automated Forces (OneSAF).
Military symbols and graphics can be created, labeled, and placed onto the sand table to set up different scenarios.
Visual aids such as color schemes and contour lines can be used to guide users to shaping the sand to replicate a previously saved 3D terrain.
Users can use their hand to navigate the different menus available in ARES as if it was the mouse.
The ARES sensor can detect and track the presence of hand(s) to identify where the user points on the sand table.
A web camera can be used to communicate with other users and provide a top-down view of the sand table to collaborators.
AR-based tablet apps and specially-made note cards can be used to project images of different vehicles on the terrain.
References
Military technology
History of computing
Mathematical tools
Cartography
Sand | Augmented Reality Sandtable | [
"Mathematics",
"Technology"
] | 760 | [
"Applied mathematics",
"Mathematical tools",
"nan",
"Computers",
"History of computing"
] |
58,054,326 | https://en.wikipedia.org/wiki/Bis-oxadiazole | Bis-oxadiazole, or more formally known as bis(1,2,4-oxadiazole)bis(methylene) dinitrate, is a nitrated heterocyclic compound of the oxadiazole family.
Bis-oxadiazole is related to bis-isoxazole tetranitrate (BITN), which was developed at the United States Army Research Laboratory (ARL). With a high nitrogen content, these compounds are poised to release a large volume of very stable N2. It is a “melt-cast” explosive material that is potentially both more powerful and environmentally friendly alternative to TNT.
Synthesis
Glyoxal condenses with hydroxylamine to yield diaminoglyoxime (DAG). Treating DAG with in the presence of base at high temperature, followed by nitration, yields bis(1,2,4-oxadiazole).
Replacement for TNT
TNT is attractive explosive because it is a melt-castable. A low melting point of about 80 °C and high decomposition temperature of 295 °C allows manufacturers to safely pour TNT into molds. The production of TNT generates hazardous waste, e.g. red water and pink water.
Bis-oxadiazole, which is also melt-castable, is about 1.5 times more powerful than TNT and yet produces less hazardous wastes.
A major challenge in the production of bis-oxadiazole is its low yield.
References
Military technology
Explosive chemicals
Oxadiazoles
Nitrate esters | Bis-oxadiazole | [
"Chemistry"
] | 320 | [
"Explosive chemicals"
] |
58,054,589 | https://en.wikipedia.org/wiki/Code%20stylometry | Code stylometry (also known as program authorship attribution or source code authorship analysis) is the application of stylometry to computer code to attribute authorship to anonymous binary or source code. It often involves breaking down and examining the distinctive patterns and characteristics of the programming code and then comparing them to computer code whose authorship is known. Unlike software forensics, code stylometry attributes authorship for purposes other than intellectual property infringement, including plagiarism detection, copyright investigation, and authorship verification.
History
In 1989, researchers Paul Oman and Curtis Cook identified the authorship of 18 different Pascal programs written by six authors by using “markers” based on typographic characteristics.
In 1998, researchers Stephen MacDonell, Andrew Gray, and Philip Sallis developed a dictionary-based author attribution system called IDENTIFIED (Integrated Dictionary-based Extraction of Non-language-dependent Token Information for Forensic Identification, Examination, and Discrimination) that determined the authorship of source code in computer programs written in C++. The researchers noted that authorship can be identified using degrees of flexibility in the writing style of the source code, such as:
The way the algorithm in the source code solves the given problem
The way the source code is laid out (spacing, indentation, bordering characteristics, standard headings, etc.)
The way the algorithm is implemented in the source code
The IDENTIFIED system attributed authorship by first merging all the relevant files to produce a single source code file and then subjecting it to a metrics analysis by counting the number of occurrences for each metric. In addition, the system was language-independent due to its ability to create new dictionary files and meta-dictionaries.
In 1999, a team of researchers led by Stephen MacDonell tested the performance of three different program authorship discrimination techniques on 351 programs written in C++ by 7 different authors. The researchers compared the effectiveness of using a feed-forward neural network (FFNN) that was trained on a back-propagation algorithm, multiple discriminant analysis (MDA), and case-based reasoning (CBR). At the end of the experiment, both the neural network and the MDA had an accuracy rate of 81.1%, while the CBR reached an accuracy performance of 88.0%.
In 2005, researchers from the Laboratory of Information and Communication Systems Security at Aegean University introduced a language-independent method of program authorship attribution where they used byte-level n-grams to classify a program to an author. This technique scanned the files and then created a table of different n-grams found in the source code and the number of times they appear. In addition, the system could operate with limited numbers of training examples from each author. However, the more source code programs that were present for each author, the more reliable the author attribution. In an experiment testing their approach, the researchers found that classification using n-grams reached an accuracy rate of up to 100%, although the rate declined drastically if the profile size exceeded 500 and the n-gram size was 3 or less.
In 2011, researchers from the University of Wisconsin created a program authorship attribution system that identified a programmer based on the binary code of a program instead of the source code. The researchers utilized machine learning and training code to determine which characteristics of the code would be helpful in describing the programming style. In an experiment testing the approach on a set of programs written by 10 different authors, the system achieved an accuracy rate of 81%. When tested using a set of programs written by almost 200 different authors, the system performed with an accuracy rate of 51%.
In 2015, a team of postdoctoral researchers from Princeton University, Drexel University, the University of Maryland, and the University of Goettingen as well as researchers from the U.S. Army Research Laboratory developed a program authorship attribution system that could determine the author of a program from a sample pool with programs written by 1,600 coders with a 94 percent accuracy. The methodology consisted of four steps:
Disassembly - The program is disassembled to obtain information on its characteristics.
Decompilation - The program is converted into a variant of C-like pseudocode through decompilation to obtain abstract syntax trees.
Dimensionality reduction - The most relevant and useful features for author identification are selected.
Classification - A random-forest classifier attributes the authorship of the program.
This approach analyzed various characteristics of the code, such as blank space, the use of tabs and spaces, and the names of variables, and then used a method of evaluation called a syntax tree analysis that translated the sample code into tree-like diagrams that displayed the structural decisions involved in writing the code. The design of these diagrams prioritized the order of the commands and the depths of the functions that were nestled in the code.
The 2014 Sony Pictures hacking attack
U.S. intelligence officials were able to determine that the 2014 cyber attack on Sony Pictures was sponsored by North Korea after evaluating the software, techniques, and network sources. The attribution was made after cybersecurity experts noticed similarities between the code used in the attack and a malicious software known as Shamoon, which was used in the 2013 attacks against South Korean banks and broadcasting companies by North Korea.
References
Military technology
Language varieties and styles
Quantitative linguistics
Computational fields of study
Source code
Computer data | Code stylometry | [
"Technology"
] | 1,091 | [
"Computer data",
"Computational fields of study",
"Computing and society",
"Data"
] |
58,055,035 | https://en.wikipedia.org/wiki/Tert-Butyldimethylsilyl%20chloride | tert-Butyldimethylsilyl chloride is an organosilicon compound with the formula (Me3C)Me2SiCl (Me = CH3). It is commonly abbreviated as TBSCl or TBDMSCl. It is a chlorosilane containing two methyl groups and a tert-butyl group. As such it is more bulky that trimethylsilyl chloride. It is a colorless or white solid that is soluble in many organic solvents but reacts with water and alcohols. The compound is used to protect alcohols in organic synthesis.
tert-Butyldimethylsilyl chloride reacts with alcohols in the presence of base to give tert-butyldimethylsilyl ethers:
(Me3C)Me2SiCl + ROH → (Me3C)Me2SiOR + HCl
These silyl ethers hydrolyze much more slowly than the trimethylsilyl ethers.
It also can silylate terminal alkynes.
Related reagents
The triflate derivative (Me3C)Me2SiOTf is used similarly but is more reactive.
References
Reagents for organic chemistry
Organochlorosilanes | Tert-Butyldimethylsilyl chloride | [
"Chemistry"
] | 254 | [
"Reagents for organic chemistry"
] |
58,055,529 | https://en.wikipedia.org/wiki/Cylindrical%20coordinate%20measuring%20machine | Cylindrical coordinate measuring machine or CCMM, is a special variation of a standard coordinate measuring machine (CMM) which incorporates a moving table to rotate the part relative to the probe. The probe moves perpendicular to the part axis and radial data is collected at regular angular intervals.
Description
Where the standard CMM uses a three dimensional Cartesian X, Y, Z system where each axis is orthogonal to the other, a Cylindrical Coordinate Measuring Machine omits the X or Y axis. The probe moves in only two axes (the vertical Z and either X or Y horizontal) and the rotating table positions the subject of inspection (a cylindrical part, hence the word "cylindrical" in the title) in a precise manner. The probe may be tactile in nature, or optical. Optical probing methods include laser interferometry and telecentric lensing.
Coordinate System
The CCMM coordinate system differs from standard cartesian coordinates in that it employs a rotating table. For this reason, a spherical coordinate system is employed to define the axis. A complete definition can be found here: The cylindrical coordinate system allows for the construction of crankshaft gages, transmission shaft gages and inspection machines for other shaft applications.
Uses
Where the standard CMM is suitable for prismatic parts, the Cylindrical CMM is ideally suited for cylindrical parts. Examples include camshafts, crankshafts, transmission shafts and other rotating parts with a length longer than their diameter. Parts with a length less than the diameter are typically measured on a roundness gauge.
Technology
The method for recording the angular position of the part will always make use of an optical encoder. However, the radial measurement probe may incorporate an optical technology, or tactile technology. Optical technologies include non-contact laser interferometry or shadow systems, while tactile systems use an optical grating.
Standardization
Standards similar to those used for a standard CMM, also verify the performance of the CCMM. The ISO 10360 series defines the characteristics of the probing system and the length measurement error:
PForm: probing deviation when measuring the form of a sphere
PSize: probing deviation when measuring the size of a sphere
EUni: deviation of measuring length on spheres from one direction
EBi: deviation of measuring length on spheres from left and right
The ISO 10360 series consists of the following parts:
ISO 10360-1 Geometrical Product Specifications (GPS) -- Acceptance and verification tests for coordinate measuring machines (CMM) -- Part 1: Vocabulary
ISO 10360-2 Geometrical product specifications (GPS) -- Acceptance and verification tests for coordinate measuring machines (CMM) -- Part 2: CMMs used for measuring linear dimensions
ISO 10360-7 Geometrical product specifications (GPS) -- Acceptance and verification tests for coordinate measuring machines (CMM) -- Part 7: CMMs equipped with imaging probing systems
ISO 10360-8 Geometrical product specifications (GPS) -- Acceptance and verification tests for coordinate measuring systems (CMS) -- Part 8: CMMs with optical distance sensors
See also
Outline of metrology and measurement
List of measuring instruments
Universal measuring machine
References
External links
The development of cylindrical coordinate measuring machines
www.vicivisionamerica.com
www.cylindricalcmm.com
rpiuk.com
www.adcole.com
Industrial machinery
Measuring instruments
Metrology
Metalworking measuring instruments | Cylindrical coordinate measuring machine | [
"Technology",
"Engineering"
] | 680 | [
"Industrial machinery",
"Measuring instruments"
] |
58,055,733 | https://en.wikipedia.org/wiki/NGC%203875 | NGC 3875 is a lenticular galaxy located about 325 million light-years away in the constellation Leo. It was discovered by astronomer William Herschel on April 27, 1785 and is a member of the Leo Cluster.
See also
List of NGC objects (3001–4000)
References
External links
3875
36675
Leo (constellation)
Leo Cluster
Astronomical objects discovered in 1785
Lenticular galaxies
6739 | NGC 3875 | [
"Astronomy"
] | 81 | [
"Leo (constellation)",
"Constellations"
] |
58,055,766 | https://en.wikipedia.org/wiki/Environmentally%20friendly%20red%20light%20flare | An environmentally friendly red-light flare was a pyrotechnic (firework) flare which used lithium-based formulations that emitted red light. A flare is used for signaling, illumination, or defensive countermeasures in civilian or military applications. It is based on a non-hygroscopic (not absorbing air) dilithium nitrogen-rich salt that served as an oxidizer and red colorant. The U.S. Army Research Laboratory and the Ludwig Maximilian Institution were credited as the research facilities for developing this product announced in January 2018.
Formulation
As of 2018, this is the first documented red-light flare compound that is based on lithium and does not contain any perchlorates, halogenated materials, or strontium-based materials. This formulation was assessed as having high color quality. To achieve the red-light emission from the flare, the authors report a formulation mixture of powdered magnesium and hexamine as fuels, nitrocellulose, an epoxy binder system, and lithium-based nitrogen salts as the oxidizer and color agent. When burned, users could observe a cool burning flame emitting a deep red color.
Previously, many formulations for red-light-emitting pyrotechnics depended on a chemical reaction involving strontium chloride (SrCl). SrCl emits the red color after the flare is ignited. This chemical compound is known as a metastable molecular emitter, meaning, it is not stable at low temperatures but stable in excited high-temperature combustion processes.
History
Before 2018, the formulations for red-light emitting pyrotechnic formulations included powdered metal fuels like magnesium, aluminum, strontium nitrate and perchlorate oxidizers, as well as carbon-based chlorinated organic materials such as poly(vinyl) chloride.
In 2014, the EPA made a decision to develop regulations on the amount of strontium present in drinking water. Strontium had been detected in 99% of all public U.S. water systems and at levels of concern in 7%. The agency reported that strontium is potentially harmful to human health. This chemical replaces calcium in the bone, interferes with bone strength, and affects skeletal development. The U.S. military training grounds were not included in the above study; therefore, the presence or percentage of strontium in their water systems were unknown. However, strontium was identified to be present in the red flares and signaling fireworks available in 2014. Due to these finding, the developers of the environmentally friendly red-light flare concluded that the development of environmentally safer flares was a necessity for users.
See also
Colored fire
Pyrotechnic colorant
References
Products introduced in 2018
Lithium compounds
Pyrotechnic compositions | Environmentally friendly red light flare | [
"Chemistry"
] | 577 | [
"Pyrotechnic compositions"
] |
58,056,118 | https://en.wikipedia.org/wiki/Loi%20pour%20une%20R%C3%A9publique%20num%C3%A9rique | The loi pour une République numérique (abr. loi numérique) is a French law first proposed by Axelle Lemaire, Secretary of State for Digital Affairs, voted on 7 October 2016.
This law aims to fulfill a two-fold purpose : "to give France a head start in the digital field by promoting an open data and knowledge policy" and to "adopt a progressive digital approach, based on individuals, to strengthen their power to act and their rights in the digital world". To do so, the law is organized around three lines: the circulation of data and knowledge, the protection of individuals in the digital society and access to digital for all.
The discussion began with an online public consultation, until 18 October 2015, then, enriched with some proposals from Internet users, the law was debated and voted in the National Assembly from 19 to 26 January 2016. It follows the "Digital Ambition" consultation led by Benoit Thieulin and Yann Bonnet, as part of the work of the National Digital Council.
It's a major IT law. It supersedes the Loi pour la confiance dans l'économie numérique (Confidence in the Digital Economy Act) of 2004.
Themes
The bill voted by MEPs at first reading introduces in particular the default opening of public data, net neutrality, an obligation of loyalty for online platforms, as well as increased protection for the personal data of Internet users. The law for a digital Republic also provides the conditions of an Internet accessible to the greatest number, through the acceleration of the coverage of the territory in very high bandwidth and in mobile telecommunications, measures for a better access of people with disabilities to online services, and the creation of a right to the continuation of the Internet connection in case of unpaid bills for households in difficulty.
Accessibility
Measures to promote accessibility for people with disabilities on public service websites had been planned. However, they are now only recommended, with an obligation to inform if the site is accessible or not, which is criticized by the association "les aveugles de France", the collective "Pour une France accessible" and the association "Faire Face".
Telephone accessibility is enacted into law in article 105, requiring telecom carriers to provide VRS and Text relay services. Call centers for both large companies and for public services are also required to provide for their own VRS and Text relay. This marks France's first official TRS services, with obligations enforced by the telecom regulator ARCEP.
Open Data and data portability
Included in the project is a default release of public data, and a recommendation for the use of interoperable formats.
Free Software and Open Formats
Article 16 of the law provides for the encouragement of the use of free software and open formats in public administration information systems, in order to preserve their control, durability and independence.
In addition, the law specifies that source codes are administrative documents that can be communicated and reused, under article 2 of the law. An implementing decree has been issued to specify the list of licenses, all of which are open source, applicable to the distribution of these source codes. A list of these source codes is published by Etalab.
Copyright issues
The definition of digital commons was discussed, with great interest during the online consultation, then withdrawn by Matignon. The cabinet of Fleur Pellerin, then Minister of Culture, is against it. Isabelle Attard condemned Matignon's withdrawal of the Commons, then submitted an amendment in favour of the Commons, which was rejected.
Freedom of panorama has also been debated, but the potential commercial use of images is likely to be a problem. A compromise amendment has been accepted, but does not satisfy all the demands of those in favour of freedom of panorama, in particular because it only allows strictly non-commercial use, which is difficult to define on the Internet.
Open access
The law promotes open access to scientific publications at no cost.
Research publications funded at least 50% by public funds can be made available free of charge after an embargo period: article 30 makes self-archiving possible for all authors after 6 or 12 months from the publication (if publicly funded).
This right of the authors is non-waivable, so any contractual provision to the contrary is superseded, even for articles published before 2016, as the law is meant to encourage green open access irrespective of academic publishers' policies.
Digital access for all
A proposal was also adopted to guarantee a right to the Internet for all, even if limited, allowing access to electronic mail or online public services. Network operators will be encouraged to develop their investments where the needs are greatest, through the prolongation and extension of the scope of over-damping to the deployment of fibre in rural areas.
Sovereign Operating System
An amendment in favour of a sovereign OS was also adopted, which provoked rather negative reactions, notably from ANSSI, due to the possible lack of realism of the proposal and of already existing solutions, such as the secure operating system CLIP, based on Linux.
Privacy
The CNIL's power would be strengthened, in the event of a recurrence, to reach 4% of turnover or 20 million euros. Amendments in favour of the right to be forgotten for minors and the closure of the online accounts of deceased persons were also approved. Group actions against companies that do not respect privacy are also planned.
Digital death
Article 63 of the Law incorporates the concept of digital death to define what becomes of a person's digital data upon death. The principles of data protection provided in the Data Protection, Files and Freedoms Act become obsolete. But the Law gives the possibility of defining directives relating to the conservation, erasure and communication of personal data after his death, failing which, it is the legal heirs who may act on these digital data.
Digital trade issues
In January 2016, the National Assembly amended the bill with amendment No. 376, adding an article 23 bis and ter making anyone renting their property on a platform such as Airbnb without the written permission of its owner liable to imprisonment, heavy fines and even eviction from their home. The amendment was defended by PS member Sandrine Mazetier.
In addition, the Senate proposes that income earned on online sales platforms would be automatically declared to the tax authorities.
Video game competitions
In January 2016, Prime Minister Manuel Valls entrusted two MPs, Rudy Salles and Jérôme Durain, with the task of "defining a legislative and regulatory framework to promote the development of video game competitions in France" to the French Secretary of State for Digital Affairs and Innovation, Axelle Lemaire. The report submitted in March 2016 by the two parliamentarians led to participation in the bill for a digital Republic, which in its chapter 4 section 2 recognizes the practice of video games in competition in France, as well as an official status for professional players.
Reactions and critics
Online consultation
This bill is the first to have been preceded by an online consultation:
an initial consultation organised by the Conseil national du numérique which identified certain subjects to be included in the law (portability, open data..)
a second consultation organised by the government on the text of the bill.
A project deemed insufficient
The LR group in the National Assembly criticised "a coherent but unfortunately very inadequate package", while the UDI group expressed concern about the digital divide. Environmentalists and the left front regretted the withdrawal of the information commons.
See also
Marco Civil da Internet, Brazilian digital law voted in 2014
Libre accès
Neutralité du réseau
Biens communs numériques
Informatique de confiance
Sécurité de l'information
Notes and references
External links, to official documents
Dossier législatif du Sénat
Dossier législatif de l'Assemblée nationale
2016 in politics
Information privacy
Academia in France
Information technology in France
Education law in France
French copyright law
Culture of France
Digital rights | Loi pour une République numérique | [
"Engineering"
] | 1,598 | [
"Cybersecurity engineering",
"Information privacy"
] |
58,057,192 | https://en.wikipedia.org/wiki/HMA%20%28VPN%29 | HMA (formerly HideMyAss!) is a VPN service founded in 2005 in the United Kingdom. It has been a subsidiary of the Czech cybersecurity company Avast since 2016.
History
HMA was created in 2005 in Norfolk, England by Jack Cator. At the time, Cator was sixteen years-old. He created HMA in order to circumvent restrictions his school had on accessing games or music from their network. According to Cator, the first HMA service was created in just a few hours using open-source code. The first product was a free proxy website where users typed in a URL and it delivered the website in the user's web browser.
Cator promoted the tool in online forums and it was featured on the front page of digg. After attracting more than one thousand users, Cator incorporated ads. HMA did not take any venture capital funding. It generated about $1,000 - $2,000 per month while the founder went to college to pursue a degree in computer science. In 2009, Cator dropped out of college to focus on HMA and added a paid VPN service. Most early HMA employees were freelancers found on oDesk. In 2012, one of the freelancers set up a competing business. HMA responded by hiring its contractors as full-time employees and establishing physical offices in London.
In 2012, the United Kingdom's government sent HMA a court order demanding it provide information about Cody Andrew Kretsinger's use of HMA's service to hack Sony as a member of the LulzSec hacking group. HMA provided the information to authorities. HMA said it was a violation of the company's terms of use to use its software for illegal activities.
In 2013, HMA added software to anonymize internet traffic from mobile devices. In 2014, the company introduced HideMyPhone! service, which allowed mobile phone users to make their calls appear to come from a different location.
By 2014, the service had 10 million users and 215,000 paying subscribers of its VPN service. It made £11 million in revenue that year. HMA had 100 staff and established international offices in Belgrade and Kyiv.
By 2015, HMA became one of the largest VPN providers. In May 2015, it was acquired by AVG Technologies for $40 million with a $20 million earn-out upon achievement of milestones, and became part of Avast after its 2016 acquisition of AVG Technologies.
In 2017, a security vulnerability was discovered that allowed hackers with access to a user's laptop to obtain elevated privileges on the device. HMA corrected the vulnerability days later.
In 2019, it was reported that HMA received a directive from Russian authorities to join a state sponsored registry of banned websites, which would prevent Russian HMA users from circumventing Russian state censorship. HMA was reportedly given one month to comply, or face blocking by Russian authorities.
In 2020, HMA introduced a no-log policy for their VPN service. Under the policy HMA will not log a user’s original IP address, DNS queries, online activity, amount of data transferred or VPN connection timestamps. Following HMA’s introduction of a no-log policy, HMA’s VPN was awarded a low risk user privacy impact rating for its no-logging policy, after it was independently audited by third-party cybersecurity firm VerSprite.
Software
HMA provides digital software and services intended to help users remain anonymous online and encrypt their online traffic. Its software is used to access websites that may be blocked in the user's country, to anonymize information that could otherwise be used by hackers, and to do something unscrupulous without being identified. HMA's privacy policy and terms of use prohibit using it for illegal activity.
HMA hides the user's IP address and other identifying information by routing the user's internet traffic through a remote server. However, experts note that the company does log some connection data including the originating IP address, the duration of each VPN session, and the amount of bandwidth used.
As of May 2018, the company had 830 servers in 280 locations across the globe and provided over 3000 IP addresses. The software also includes a kill switch across all platforms.
Privacy
According to Invisibler, HMA VPN appears to have cooperated with US authorities in handing over logs in a hacking case. This led to the arrest of a hacker in what is known as the "LulzSec fiasco".
Reception
In 2015, a review in Tom's Hardware said HMA was easy to use, had good customer service, and a large number of server locations to choose from, but criticized it for slowing internet speeds. In contrast, Digital Trends said HMA had strong speeds and good server selection, but wasn't fool-proof at ensuring anonymity, because it stored user activity logs (in 2020, HMA announced that it would no longer log user activity). In 2017, PC World noted that it was difficult to measure the effect a VPN service has on internet speed, because of variables like location, internet service speeds, and hardware.
A 2016 review in PCMag gave the HMA Android app 3 out of 5 stars. It praised HMA for its server selection and user interface, but criticized it for price, speed, and the lack of advanced features. In 2018, PCMag gave similar feedback on the HMA VPN service. PC World’s 2017 review also praised HMA's simple user interface, but criticized the lack of advanced features, saying the software was ideal for casual users that do not need advanced configuration options.
References
External links
Avast
Virtual private network services
Computer companies established in 2005
Computer security software
Proxy servers
2005 establishments in England
British companies established in 2005
2016 mergers and acquisitions
British subsidiaries of foreign companies
Gen Digital software | HMA (VPN) | [
"Engineering"
] | 1,222 | [
"Cybersecurity engineering",
"Computer security software"
] |
73,398,697 | https://en.wikipedia.org/wiki/Gnomoniopsis%20castaneae | Gnomoniopsis castaneae (synonym Gnomoniopsis smithogilvyi) is a fungus of the order Diaporthales that is the most important cause of brown chestnut rot, an emerging disease that damages the fruit of chestnuts. It also causes cankers and necrosis on leaves and on chestnut galls caused by the gall wasp, Dryocosmus kuriphilus. It has been observed to cause cankers in chestnut wood. Additionally, it can cause cankers on other chestnut species, red oak, hazelnut trees, less severe damage to some nut trees, and lives as an endophyte on other nut trees. The disease has been reported in Europe, Oceania, and has recently been found in North America; for this reason, the fungus is considered a potential threat to the reintroduction of the American chestnut.
In brown chestnut rot, Gnomoniopsis castaneae infects the kernel of the nut with browning and necrosis of endosperm and embryo. Brown chestnut rot is expressed cryptically with apparently healthy nuts found after harvest to exhibit internal rot. The fungus is believed to initially establish endophyte colonization of chestnut tissues, only becoming pathogenic with ripening of the nuts. Early on, parasitized nuts are difficult to distinguish from good nuts, rot only being detected when processed or eaten. The route of infection is uncertain but is believed to be either infection of chestnut flowers by ascospores or conidia or by inoculum entrance through shell defects. The fungus persists as a saprophyte in duff, such as burs, fallen leaves and other residua, which act as the reservoir for formation of perithecia with eventual release of spores. The nature of the transfer of inoculum and dispersal in time and space and the effect of climate is unknown.
The fungus also kills the chestnut gall wasp Dryocosmus kuriphilus and has been proposed as a potential natural biocontrol agent against insect pests, based on studies of its effect on Plodia interpunctella and Trogoderma granarium. Exposure of the fungus to the commercial biofungicide Serenade® ASO (Bacillus amyloliquefaciens QST 713; ASO) induced the fungus to produce the mycotoxins 3-nitropropionic acid and diplodiatoxin. Exposure of the fungus to the chemical fungicide Horizon® (tebuconazole; HOR) induced the fungus to produce diplodiatoxin. These mycotoxins might present a health hazard to human consumers of chestnuts treated with these fungicides.
In a chestnut orchard context, strategies for managing Gnomoniopsis castaneae infections include aggressive pruning of infected branches, maintaining tree health via proper hydration and nutrient provision so as to improve resistance, and fungicide application when necessary. Since this fungus can spread through spores, proper sanitation and disposal of infected plant material are also crucial to limit its spread.
References
Gnomoniaceae
Fungus species | Gnomoniopsis castaneae | [
"Biology"
] | 635 | [
"Fungi",
"Fungus species"
] |
73,398,928 | https://en.wikipedia.org/wiki/Uniplacotomia | Uniplacotomia is a class of placozoans encompassing the vast majority of the phylum, with the exception of Polyplacotoma. It was established in 2022. It comprises the orders Trichoplacea, Cladhexea and Hoilungea. Their morphology is consistent across the class, resembling the typical Trichoplax as mostly rounded, flat organisms rather than the polytomous, branching structure exhibited by Polyplacotomia.
Despite a uniform exterior morphology, Uniplacotomia exhibits an important degree of diversity in molecular morphology, with at least two dozen species estimated to exist.
References
Animal classes
Placozoa
Parazoa | Uniplacotomia | [
"Biology"
] | 143 | [
"Parazoa",
"Animals",
"Animal stubs"
] |
73,399,159 | https://en.wikipedia.org/wiki/Cladhexea | Cladhexea is a recently created placozoan order comprising yet-undescribed species. Named in 2022, it is believed to be sister to Hoilungea, and corresponds to Clade VI of the literature.
Etymology
The name comes from Ancient Greek kládos (clade) and hexa (six), referring to its specimens previously being assigned to placozoan Clade VI in literature.
References
Placozoa
Animal orders | Cladhexea | [
"Biology"
] | 95 | [
"Animals",
"Animal stubs"
] |
73,399,196 | https://en.wikipedia.org/wiki/Polyplacotomia | Polyplacotomia is a class of placozoans, to this date only comprising Polyplacotoma mediterranea. It was established in 2022. Their morphology is strikingly different from other placozoans in Uniplacotomia, exhibiting a highly ramified, branching structure with multiple amoeboid projections. It differs from Uniplacotomia by 76 uniquely present and 600 absent genes.
References
Placozoa
Animal classes | Polyplacotomia | [
"Biology"
] | 99 | [
"Animals",
"Animal stubs"
] |
73,400,837 | https://en.wikipedia.org/wiki/Osmium%28IV%29%20fluoride | Osmium(IV) fluoride is an inorganic chemical compound of osmium metal and fluorine with the chemical formula .
Synthesis
Passing fluorine over heated osmium at 280 °C:
Reaction products can be contaminated with other osmium fluorides.
Physical properties
Osmium(IV) fluoride compound forms yellow hygroscopic crystals.
Chemical properties
Osmium(IV) fluoride reacts with water.
References
Osmium compounds
Fluorides
Platinum group halides | Osmium(IV) fluoride | [
"Chemistry"
] | 99 | [
"Fluorides",
"Salts"
] |
73,400,967 | https://en.wikipedia.org/wiki/Krypton%20tetrafluoride | Krypton(IV) fluoride is a hypothetical inorganic chemical compound of krypton and fluorine with the chemical formula . At one time researchers thought they had synthesized it, but the claim was discredited. The compound is predicted to be difficult to make and unstable if made. However, it is predicted to become stable at pressures greater than 15 GPa. Theoretical analysis indicates would have an approximately square planar molecular geometry.
Synthesis
The claimed synthesis was by passing electric discharge through krypton-fluorine mixture:
Physical properties
The claimed compound formed white crystalline solid. Thermally, it is less stable than .
References
Krypton compounds
Fluorides
Nonmetal halides
Hypothetical chemical compounds | Krypton tetrafluoride | [
"Chemistry"
] | 145 | [
"Inorganic compounds",
"Hypotheses in chemistry",
"Salts",
"Inorganic compound stubs",
"Theoretical chemistry",
"Hypothetical chemical compounds",
"Fluorides"
] |
73,401,172 | https://en.wikipedia.org/wiki/Krypton%20hexafluoride | Krypton hexafluoride is an inorganic chemical compound of krypton and fluorine with the chemical formula . It is still a hypothetical compound. Calculations indicate it is unstable.
History
In 1933, Linus Pauling predicted that the heavier noble gases would be able to form compounds with fluorine and oxygen. He also predicted the existence of krypton hexafluoride. Calculations suggest it would have octahedral molecular geometry.
So far, out of all possible krypton fluorides, only krypton difluoride () has actually been synthesized.
References
Krypton compounds
Fluorides
Nonmetal halides
Hexafluorides
Fluorinating agents
Hypothetical chemical compounds | Krypton hexafluoride | [
"Chemistry"
] | 150 | [
"Inorganic compounds",
"Hypotheses in chemistry",
"Salts",
"Inorganic compound stubs",
"Fluorinating agents",
"Theoretical chemistry",
"Hypothetical chemical compounds",
"Reagents for organic chemistry",
"Fluorides"
] |
73,402,384 | https://en.wikipedia.org/wiki/Leucoagaricus%20flavus | Leucoagaricus flavus is a species of mushroom-producing fungus in the family Agaricaceae.
Taxonomy
It was described in 2022 by the mycologists Phongeun Sysouphanthong and Naritsada Thongklang who classified it as Leucoagaricus flavus.
Description
Leucoagaricus flavus is a small dapperling mushroom with thin (2mm thick) white flesh.
Cap: 1.5–2 cm wide, umbonate and expanding to flat or plano-convex with a slight umbo. The surface is pale yellow with a fibrillose yellow coating that may peel to reveal a whitish to pale yellow background whilst the centre umbo is smooth with a slightly more pronounced yellow tone.The cap margins are straight and fibrillose with the fibrils being of the same colour as the centre, sulcate striations and fringes are present when mature. Gills: Free, slightly crowded and pale to pastel yellow. They are up to 1.5mm wide, have an eroded edge and bulge in the middle (ventricose). Stem: 3-3.5 cm long and 3-5mm thick, cylindrical or tapering upwards slightly from the wider base. The surface is yellowish-white with a fibrillose or soft, hairy coating of the same colour and the interior is hollow with white fibrils inside. The stem ring is located towards the middle of the stem (median) and has a fibrillose coating the same colour as the cap surface. Spores: 4.8-5.3 x 3.5-4 μm. Ellipsoidal to ovoid with a slightly thick wall and no germ pore. Hyaline. Dextrinoid, congophilous, cyanophilous and metachromatic. Basidia: 13-16 x 6–7.5 μm. Clavate. Smell: It has a distinct but soft flowery smell.
Etymology
The specific epithet flavus derives from the Latin flavus meaning yellow. This refers to the colour of the mushrooms.
Habitat and distribution
The specimens studied were found in deciduous and bamboo forests in Laos during the rainy season of October to November where they were growing solitary on soil.
Similar species
Leucoagaricus orientiflavus is similar in appearance and closely related but can be distinguished via microscopic details.
Leucoagaricus houaynhangensis differs via the presence of the greenish colour to the cap and grey to black scales as well as microscopic details. Leucoagaricus sulphurellus, Leucoagaricus viridiflavoides and Leucoagaricus viridiflavus are similarly distinguished.
Leucocoprinus birnbaumii and other yellowish species like Leucocoprinus flavescens can be distinguished by the presence of distinct striations on their caps.
References
flavus
Fungi described in 2022
Fungi of Asia
Fungus species | Leucoagaricus flavus | [
"Biology"
] | 620 | [
"Fungi",
"Fungus species"
] |
73,402,513 | https://en.wikipedia.org/wiki/Breastmilk%20medicine | Breastmilk medicine refers to the non-nutritional usage of human breast milk (HBM) as a medicine or therapy to cure diseases. Breastmilk is perceived as an important food that provides essential nutrition to infants. It also provides protection in terms of immunity by direct transfer of antibodies from mothers to infants. The immunity developed via this mean protects infants from diseases such as respiratory diseases, middle ear infections, and gastrointestinal diseases. HBM can also produce lifelong positive therapeutic effects on a number of chronic diseases, including diabetes mellitus, obesity, hyperlipidemia, hypertension, cardiovascular diseases, autoimmunity, and asthma.
Therapeutic use of breastmilk has long been a part of natural pharmacopeia, and ethnomedicine. The effectiveness of HBM and fresh colostrum as a treatment for inflammatory disorders such as rhinitis, skin infection, soring nipples, and conjunctivitis has been reported by public health nurses. Currently, many breastmilk components have shown therapeutic benefits in preclinical studies and are being evaluated by clinical studies.
Anti-inflammatory effects
HBM can be used to treat inflammations. Breastfeeding has an anti-inflammatory effect that is conveyed by its chemical components’ interaction with body cells. The major chemical component that produces the anti-inflammatory effect in both colostrum and transitional milk are glycoprotein and lactoferrin. Lactoferrin has multiple actions including lymph-stimulatory, anti-inflammatory, anti-bacterial, anti-viral, and anti-fungal effects. The anti-inflammatory effects of lactoferrin are attributed to its iron-binding properties, inhibition of inflammation-causing molecules including interleukin-1β (IL-1β) and tumor necrosis factor-alpha (TNF-α), stimulation of the activity and maturation of lymphocytes as well as preservation of an antioxidant environment. Besides, lactoferrin protects infants against bacterial and fungal infections in combination with other peptides present in HBM.
Respiratory viral infection in infants
Lactoferrin in HBM can also inhibit the invasion and proliferation of respiratory syncytial virus (RSV), which is a virus commonly found in the human respiratory tract and causes mild cold-like symptoms. Lactoferrin can interact directly with the F glycoprotein which is a protein on the surface of the virus that is responsible for presenting the virus to body cells and causing infections.
Adenovirus is another group of viruses that targets the mucosal membrane of the human respiratory tract. It usually causes mild to severe infection with symptoms like the common cold or flu. Lactoferrin can prevent infection of adenovirus since it can interfere with the primary receptors of the virus. HBM regurgitation into the nose after breastfeeding is a way to eliminate these mucosal bacteria and protect infants against recurring nose infections in breastfed infants in the long term.
Skin Problems: atopic eczema and diaper dermatitis
Atopic eczema is an inflammatory disorder that occurs in the outermost skin layer called the epidermis. This skin disorder affects 50% of infants in the first year after birth. Infants suffering from atopic eczema are characterized by intense itching, redness, and crusting in their skin. Skin thickening may result in chronic or sub-acute patients due to scratching and fissuring over time.
One of the commonly used medications for atopic eczema is non-prescription cream containing an anti-inflammatory agent 1% hydrocortisone. On the other hand, applying HBM on the skin as ointments is therapeutically beneficial to infants with mild to moderate atopic eczema. It is evidenced that, compared to 1% hydrocortisone, HBM has similar effectiveness as 1% hydrocortisone to relieve infants’ inflaming skin conditions.
Diaper dermatitis is another prevalent infant dermatological disorder. Common clinical features of diaper dermatitis include inflamed, itchy, tender skin and soreness in the diaper area. Study results have shown that human breastmilk is highly effective in healing diaper rash.
There is much evidence supporting the anti-inflammatory effect of HBM. The immunological components in HBM help strengthen the baby’s immune system. These immunological components include antimicrobial proteins that can inhibit or kill a wide range of pathogens whose invasion may lead to an inflammatory response. This antimicrobial effect could be achieved by indirectly creating an unfavorable environment for the growth of pathogens by modifying commensal flora, pH, or level of bacterial substrates. The antimicrobial effect is also brought by an antibody immunoglobulin A (IgA) which is the prenominal immunoglobulin present in HBM that can protect infants from a variety of skin infections.
Nipple problems: sore nipples
The painful nipple is a common difficulty confronted by mothers who decided to carry out breastfeeding. Topical application of expressed breastmilk has long been a non-pharmacological intervention to reduce nipple pain. According to the research outcome of many studies, topical application of HBM can help reduce the perception of nipple pain in a treatment course of 4 to 5 days. It is also stated that HBM is more effective in lowering pain perception than Lanolin.
However, another study indicates that Lanolin produces lower pain levels in mothers with nipple pain than HBM. This study stated that lanolin shows a better therapeutic effect for healing rates, nipple trauma, and nipple pain. Although lanolin may be more efficacious than HBM to cure nipple problems, HBM is not proven to be ineffective to treat nipple pain. Considering HBM is more easily available than Lanolin, it is still useful for treating nipple problems in a practical sense.
Eye Problems
Traditional uses
The topical application of breastmilk as a treatment for an infectious disease called conjunctivitis has been present since ancient times in different nations such as ancient Egypt, Rome, Greece, etc. HBM was also recommended by the Greek physician Galen as a remedy for conjunctivitis. Physicians in early modern England recommended human milk for conditions ranging from mild symptoms such as soreness to even blindness. Healers in that era even believed that a mixture of HBM with other components could restore eyesight.
Scientific findings
Evidence from clinical research has shown that applying HBM can prevent people from getting conjunctivitis infections.
Gonorrhea is a sexually transmitted infection. Besides sex-borne transmission, it can also be transmitted to babies during childbirth. This infectious disease can cause neonatal conjunctivitis, which could lead to blindness, if untreated. Hospitals in the United States are required to apply antibiotics to the eyes of new-born within one hour of childbirth to prevent the development of conjunctivitis. This is because certain bacteria in HBM are found to be effective against gonorrhea bacteria and may serve as a convenient and readily available substitute for antibiotics in places where antibiotics are not widely available.
Breastmilk in umbilical cord care
After labor in childbirth, the umbilical cord is clamped and cut, and part of it stays in contact with the infant. The remaining part of the umbilical cord dries out and eventually separates after 5–15 days. In taking care of the umbilical cord, the dry care method involving soap and water is recommended by the WHO and many national health organizations. For the use of HBM in umbilical cord care, clinical studies found that topical application of breast milk will lead to a shorter time of cord separation than other methods including ethanol and dry cord care.
Anti tumoricidal and anti-bacterial effects
Human alpha-lactalbumin is a natural protein component of HBM. It can be extracted by chromatography from breast milk. It complexes with oleic acid to form a protein called the “human alpha-lactalbumin made lethal to tumor cells” (HAMLET). The HAMLET complex induces apoptosis in lung carcinoma cells. In in vitro and animal model studies, HAMLET has shown preventative and therapeutic effects in reducing and controlling tumor growth. The physiological effects of HAMLET may explain the proposal that breastfeeding has protective effects for mothers and children against cancer, as shown by the association length of breastfeeding and childhood cancer incidence. The HAMLET has also been found to have anti-bacterial effects through the inhibition of enzymes in glycolysis.
Role in society
Researchers’ interest in HBM is led by the discovery of a number of chemical components in HBM. These components include growth factors, cytokines, and a heterogeneous population of cells which are stem cells, probiotic bacteria, and the HAMLET complex.
By considering the easy accessibility of HBM and high prevalence of infant inflammation disorders, breastmilk may be a cheap and convenient ways to relieve inflammatory symptoms. The prophylactic antibiotic use of human milk may be important in areas where mothers and infants do not have easy access to medicine, such as people living in developing countries. Under these circumstances, practice of HBM therapy as medicine will be a determining factor in infant recovery and survival.
General limitations
Breastfeeding difficulties
Breastfeeding may not be feasible and easy for some mothers due to psychological or physiological reasons. For instance, breastfeeding self-efficacy, the mother's confidence in her breastfeeding abilities, is positively associated with exclusive breastfeeding while postpartum depression makes it more difficult to breastfeed. Mothers who have undergone breast surgeries such as mastectomy may have reduced capabilities of HBM production.
Suitability of breastmilk
For some individuals, HBM may not be suitable for use, as it may transmit of viruses and other pathogens to infants. For instance, cytomegalovirus, HIV, and bacterial infections from the mother may be transmitted through HBM, causing complications for infants.
Evaluation of medical effectiveness of breastmilk
There is difficulty in the generalization of study results in evidence-based practice due to inconsistencies in the clinical study findings on breastfeeding medicine. HBM compositions are diverse among different individuals, or the same individual at various times. It is influenced by factors such as maternal diet and changes at various times after pregnancy. For instance, protein composition in HBM is higher in the earlier stages of lactation. Gradually, the mother produces more mature milk, which is whiter in color, compared to the yellowish colostrum. These changes may affect the effectiveness of HBM in medical use.
References
Medicine
Medicine | Breastmilk medicine | [
"Biology"
] | 2,196 | [
"Medicine"
] |
73,402,642 | https://en.wikipedia.org/wiki/David%20Purves | Dr. David Purves (9 April 1924 – 3 January 2015) was a Scottish environmental scientist, playwright and poet, and a champion of the Scots language.
Early life
Purves was born in Selkirk, Scotland, the only son of James Alexander Purves, a master grocer based in Galashiels, and his wife May Lees. He was brought up in the Borders, and educated at Galashiels Academy.
He served in the Royal Air Force in World War II, training as a bomber navigator in Canada.
Career as an environmental scientist
After the war, he studied at the University of Edinburgh, gaining an honours degree and PhD in biochemistry. In 1956, he was appointed head of the Trace Element Department at the East of Scotland College of Agriculture, where he worked with the agricultural advisory service on trace element deficiency and toxicity problems. In 1977, his scientific monograph Trace-Element Contamination of the Environment, which highlighted the social and ecological implications of allowing metals to be dispersed into the biosphere as contaminants, was published by Elsevier. A revised edition was published in 1985. In 1980, he was commissioned by the United Nations Food and Agriculture Organisation to recommend standards for the disposal of sewage-sludge to land. He retired from the Edinburgh School of Agriculture in 1982, but maintained an interest in global environmental problems as Supervisor of its Central Analytical Department until 1987.
Scottish National Party
Purves contested Roxburgh, Selkirk and Peebles as a Scottish National Party candidate in the parliamentary election in February 1974. He contributed a chapter on "Environmental Policy in an Independent Scotland" to The Radical Approach: Papers on an Independent Scotland, edited by Gavin Kennedy and published by Palingenesis Press Ltd. in 1976. He was later elected to the SNP's National Council and in the 1980s was convener of its Environment Policy Committee.
Scots language
Purves was active in promoting the Scots language, taking a particular interest in the development of a standard orthography. In 1979, he contributed a paper on the spelling of Scots to The Scottish Literary Journal. In 1985, at Edinburgh University's School of Scottish Studies, he chaired a meeting of contemporary writers in Scots which agreed guidelines for Scots spelling. These were later published by the Scots Language Society as Recommendations for Writers in Scots. The Saltire Society published his book, A Scots Grammar, in 1997, and a revised and extended edition in 2002. His paper The Way Forward for the Scots Language was published by the Scottish Centre for Economic and Social Research in 1997.
Poetry
His poems in Scots were published in a range of magazines, including AKROS, Lines Review, Cencrastus, Chapman, Lallans, Markings, Northwords and Reforesting Scotland. Two collections of his poems in Scots have been published: Thrawart Threipins in 1976, and Hert’s Bluid, Chapman 1995. His poems "On Mairriage" and "On Bairns" are included in the Scottish Poetry Library's anthologies, Handfast and Handsel respectively. His poems "Crabbit Angels" and "Cleikit" were published in The Edinburgh Book of Twentieth-Century Scottish Poetry published in 2005. His poems "Heid Bummers" (2006) and "Mirzah’s Brig" (2009) were included in The Smeddum Test, an anthology of 21st Century poems in Scots published by Kennedy & Boyd in 2013. His poems "Hard Wumman", "Resurrection" and "Brierie Law" were included in J. Derrick McClure's A Kist o Skinklan Things, an anthology of Scots poetry from the first and second waves of the Scottish Renaissance, published by the Association for Scottish Literary Studies in 2017.
Purves also rendered two hundred ancient Chinese poems in Scots, in four collections of fifty poems, entitled, Ane Auld Sang, Gean Blossoms, Jade Lute and Chrysants.
He was a member of the British Haiku Society.
Drama
Three of his plays in Scots, The Puddok an the Princess, The Knicht o the Riddils and Whuppitie Stourie, have been professionally produced. Other plays based on folk and fairy-tale themes are The Ill Guidmither, based on a tale collected by Peter Buchan in 1829, and Pompitie Finnds a Needle, a dramatisation of a children's story by Agnes Grozier Herbertson which was given a reading at Edinburgh Playwrights Workshop. The Puddok an the Princess marked the beginning of a long collaboration with Charles Nowosielski of Theatre Alba. The company's production of the play won a Fringe First Award at the Edinburgh Festival Fringe in 1985. It had a total of eight productions and was toured by Theatre Alba in 1986 and 1988. The Knicht o the Riddils was staged at the Brunton Theatre, Musselburgh, in November and December 1987. Whuppitie Stourie, based on a Scottish version of the fairytale Rumpelstiltskin, was toured by Theatre Alba between 30 October and 28 November 1989.<ref>"A Measure of Scots", The List, Issue 105, 29 September - 12 October 1989, p. 45</ref>Whuppitie Stourie tour listings, The List, issue 107, 27 October – 9 November 1989, p. 52,
In an interview given to The Scotsman while The Knicht o the Riddils was playing in Musselburgh, Purves told Catherine Lockerbie that he was not trying to emulate the historical emphasis of admired Scots dramatists like Robert Maclellan. "I like to be free of the constraints of history," he said. "I prefer to go back into a fabulous period, to a world which never really existed but which has a reality of its own."
Purves also rendered works by other playwrights into Scots. His The Thrie Sisters. a translation of Three Sisters by Anton Chekhov, was produced by Theatre Alba at Lauriston Halls on the Edinburgh Festival Fringe in 1999. His The Tragedie o Macbeth, a translation and adaptation of William Shakespeare's Macbeth was published in 1992, given a reading by Edinburgh Playwrights Workshop in March of that year, and staged by Theatre Alba in Duddingston Kirk Gardens on the Festival Fringe in August 2002. The Ootlaw, a translation into Scots of August Strindberg's The Outlaw was staged by Theatre Alba at Duddingston Kirk on the 2009 Fringe. He also translated Eugene Schwartz's Little Red Riding Hood into Scots.
He was a member of the Scottish Society of Playwrights.
Lallans magazine
David Purves was elected as Preses of the Scots Language Society from 1983 to 1986 and served as editor of Lallans from 1987 to 1995. He was also co-editor with Neil R. MacCallum of Mak it New, an anthology of writing from the magazine, in 1995.
Bibliography
"Ane Ill Turn: an example of the Standard Scots orthography", in Annand, J.K. (ed.), Lallans, Number 2: Whitsunday 1974, p. 20,
"The Spelling of Scots", in Annand, J.K. (ed.), Lallans, Number 4: Whitsunday 1975, pp. 26 – 28
Trace-Element Contamination of the Environment, Elsevier, Amsterdam, 1977,
"Environmental Policy in an Independent Scotland", in Kennedy, Gavin (ed.) (1976), The Radical Approach: Papers on an independent Scotland, Palingenisis Press Ltd., Edinburgh, pp. 88–92,
Thrawart Threipins, The Aquila Publishing Co. Ltd., Breakish, Isle of Skye, 1976,
"A Scots Orthography", in The Scottish Literary Journal, Supplement No. 9, Spring 1979
"The Scots Language in Drama", Electric Scotland
The Puddok an the Princess, Brown, Son & Ferguson Ltd., Glasgow, 1992,
The Tragedie o Macbeth: A Rendering into Scots of Shakespeare's Play, Rob Roy Press, 1992,
J.K. Annand: A Makar tae Mynd, Obituary, in Renton, Jennie (ed.), Scottish Book Collector, Volume 3, Number 12, August - September 1993, Edinburgh, p. 33
"The Lest o the Ettins", in Bryan, Tom (ed.), Northwords Issue 6, Ross and Cromarty Association of Writers' Groups, p. 19,
Hert's Bluid, Chapman Publications, Edinburgh, 1995,
with Neil R. MacCallum, Mak it New: An Anthology of Twenty-one Years of Writing in Lallans, The Mercat Press, Edinburgh, 1995,
The Way Forward for the Scots Language, Scottish Council for Economic and Social Research, Peterhead
A Scots Grammar: Scots Grammar and Usage, The Saltire Society, Edinburgh, 2002,
"The Language of Scots", in Clark, Nick (ed.), Poetic Hours, Autumn 2004, Nottingham, p. 9,
"Haiku & Zen Buddhism", in Glen, Duncan (ed.), Scottish Poetry Library Newsletter, January 2005, Scottish Poetry Library, Edinburgh, p. 5,
"Polishing the Glass: Japanese Masters in Scots", in Clark, Nick (ed.), Poetic Hours, Spring 2005, Nottingham, pp. 8 & 9,
"in ilka age: The Poetry of Li Po", in Clark, Nick (ed.), Poetic Hours, Autumn 2005, Nottingham, pp. 4 & 5,
"From the Chinese of Ssü-K'ung T'u", in Hendry, Joy (ed.), Chapman'' 109, 2007
Personal life
David Purves married Lilian Rosemary Stewart, a primary school teacher, at Cramond Parish Kirk, Edinburgh, on 19 September 1953. The couple had met at university. They spent the first four years of their married life in Stow, in the Borders. In 1957 they returned to Edinburgh, living first in Meadowfield Terrace, and then in Hillpark Avenue, Cluny Gardens, and Strathalmond Road. The couple had three sons: Graeme Alexander Stewart (b. 1954), Jamie Scott (b. 1958), and David Neil (b. 1964).
References
1924 births
2015 deaths
20th-century Scottish scientists
21st-century Scottish scientists
Environmental scientists
Scottish environmentalists
Alumni of the University of Edinburgh
20th-century Scottish dramatists and playwrights
21st-century Scottish dramatists and playwrights
20th-century Scottish poets
21st-century Scottish poets
Lallans poets
Scots-language poets
Scots-language writers
Scots language activists
Scottish magazine editors
Scottish nationalists
Writers from the Scottish Borders
People from Selkirk, Scottish Borders
People educated at Galashiels Academy
Royal Air Force personnel of World War II | David Purves | [
"Environmental_science"
] | 2,246 | [
"Environmental scientists",
"British environmental scientists"
] |
73,402,797 | https://en.wikipedia.org/wiki/Leucoagaricus%20griseosquamosus | Leucoagaricus griseosquamosus is a species of mushroom-producing fungus in the family Agaricaceae.
Taxonomy
It was described in 2022 by the mycologists Phongeun Sysouphanthong and Naritsada Thongklang who classified it as Leucoagaricus griseosquamosus.
Description
Leucoagaricus griseosquamosus is a small dapperling mushroom with thin (1mm thick) white flesh that discolours reddish-white when cut.
Cap: 1–2 cm wide, umbonate and expanding to flat with a slight umbo. The surface is white and covered with grey to greyish-brown scales which are darker at the smooth or slightly coarse umbo. It discolours reddish-white when touched or damaged. The margins are straight and have white fibrils and sulcate striations when mature. Gills: Free, moderately crowded and white. They are 2-4mm wide, have an eroded edge and bulge in the middle (ventricose). When touched they discolour reddish-white. Stem: 2.3-3.3 cm long and 2.5-3.5mm thick, cylindrical and tapering upwards slightly from the slightly wider base. The surface is white with a white fibrillose coating and likewise discolours reddish-white when touched and the interior is hollow with white fibrils inside. The white, fibrillose stem ring is located towards the top of the stem (superior) but is fragile and may disappear when mature. Spore print: White. Spores: 6–7.5 x 4-4.5 μm. Ellipsoidal to ovoid with a slightly thick wall. Hyaline. Dextrinoid, congophilous, cyanophilous and metachromatic. Basidia: 14-17 x 7-8 μm. Clavate, 4 spored.
Etymology
The specific epithet griseosquamosus derives from the Latin griseus meaning grey and squamosa meaning scales. This refers to the colour of scales on the cap of the mushrooms.
Habitat and distribution
The specimens studied were found in deciduous forests in Laos during the rainy season where they were growing solitary or in small groups on soil.
Similar species
Leucoagaricus melanotrichus is similar but has a grey cap background with purplish-brown scales. It was documented from Morocco and may also be found in Europe.
Leucocoprinus heinemannii has a similar colouration but distinct striations on the cap.
Lepiota atrodisca has darker scales with a striate margin that is prone to splitting and a black margin on the annulus.
References
griseosquamosus
Fungi described in 2022
Fungi of Asia
Fungus species | Leucoagaricus griseosquamosus | [
"Biology"
] | 589 | [
"Fungi",
"Fungus species"
] |
73,402,842 | https://en.wikipedia.org/wiki/Bilge%20pollution | Bilge pollution is a type of water pollution that occurs when the bilge water in a ship's hull is discharged into the ocean. In a research published in 2019, it was estimated that up to 3000 cases of bilge dumping happen in Europe every year. According to another estimate, approximately 52.8 million gallons of pollutants are discharged into the ocean annually.
Treatment of bilge water, in which all contaminants are removed, is the preferred method of dealing with bilge water pollution. Due to increased operational costs, companies mostly dump waste directly into the ocean without properly processing it. Due to the presence of carcinogenic chemicals, bilge water waste is considered a threat to marine life and human health.
References
Ocean pollution | Bilge pollution | [
"Chemistry",
"Environmental_science"
] | 152 | [
"Ocean pollution",
"Water pollution"
] |
73,403,570 | https://en.wikipedia.org/wiki/Anthony%20J.%20Dias | Anthony J. Dias is a retired ExxonMobil materials scientist known for scientific contributions in polyolefins and elastomers which led to commercialized products.
Education
Dias earned a B.S. in chemistry from Kean College in 1982. He earned a Ph.D. in Polymer Science and Engineering from the University of Massachusetts Amherst in 1987 under Prof. Thomas J. McCarthy.
Career
Dias joined ExxonMobil Chemical Company in 1988 and has held both research and management responsibilities. His most cited scientific work concerned the development of metallocene catalysts on a nonreacting polystrene support to replace reactive silica supports. Dias retired in June 2021 as Chief Scientist.
Awards and recognition
1998 - Sparks–Thomas award from the ACS Rubber Division
2015 - Fellow of the American Chemical Society
2018 - Division Fellow, Polymeric Materials: Science and Engineering
References
Polymer scientists and engineers
ExxonMobil people
Living people
Fellows of the American Chemical Society
University of Massachusetts Amherst alumni
Kean University alumni
Year of birth missing (living people)
Place of birth missing (living people)
20th-century American chemists
21st-century American chemists | Anthony J. Dias | [
"Chemistry",
"Materials_science"
] | 235 | [
"Polymer scientists and engineers",
"Physical chemists",
"Polymer chemistry"
] |
73,403,703 | https://en.wikipedia.org/wiki/Leucoagaricus%20croceovelutinus | Leucoagaricus croceovelutinus is a species of mushroom-producing fungus in the family Agaricaceae.
Taxonomy
It was described in 1972 by the French mycologists Marcel Bon and Jacques Boiffard who classified it as Leucocoprinus croceovelutinus.
It was reclassified by Marcel Bon in 1976 as Leucoagaricus croceovelutinus.
The variation Leucocoprinus croceovelutinus var. diversisporus was described in 1990 by the British mycologist Derek Reid but is now considered a synonym.
Description
Leucoagaricus croceovelutinus is a small dapperling mushroom with thin white or pale yellow flesh that discolours red within a minute of being exposed. This reaction is hastened by exposure to ammonia fumes but does not result in a green colour like some similar species.
Cap: 3–6 cm wide, starting convex before flattening with a very slight umbo. The surface is covered with adpressed red-brown scattered scales against a white background with a darker red-brown centre disc. Upon contact or age the surface discolours red obscuring the white background colour and making for a burgundy tone against the brown. Orange to purple tones may also come through with bruising or age. Gills: Free, crowded, ventricose and white or pale yellow but orange red on bruising. The gill edges become brown with age or upon handling and this is most noticeable towards the cap margins. When dry they become dark grey. Stem: 7-10cm tall and 4-5mm thick tapering upwards from the swollen, club shaped base. The surface is pure white and silky at first sometimes with a rosy colour at the base but it soon becomes rose coloured across the length except at the apex, then reddish-brown and brown at the base, which finally becomes blackish-purple. When dry this darker colour spreads over the entire stem. The interior flesh is white but discolours orange-red when exposed. The pendant, membranous stem ring is generally persistent and is located towards the middle or top of the stem (median to superior), it is white with a wine-red margin but discolours dull red with age. Spore print: White. Spores: (7) 7.5–8.5 (9) x 3.5–4.5 μm. Amygdaliform to ovoid without a germ pore. Dextrinoid.
Habitat and distribution
The specimens studied by Bon and Boiffard were found on humus under deciduous trees near the Le Veillon beach near Talmont Saint Hilaire, France. Reid suggests that it may be associated with Robinia, Quercus and Ligustrum trees based on the limited recorded collections available at the time which were in France, Netherlands and Hungary. The species has also been recorded in Bulgaria.
References
croceovelutinus
Fungi described in 1972
Fungi of Europe
Fungus species | Leucoagaricus croceovelutinus | [
"Biology"
] | 617 | [
"Fungi",
"Fungus species"
] |
73,404,288 | https://en.wikipedia.org/wiki/Bego%C3%B1a%20Vitoriano | Begoña Vitoriano Villanueva (born 1967) is a Spanish applied mathematician and operations researcher whose work concerns the logistics of humanitarian aid and disaster relief. She is an associate professor in the Department of Statistics and Operational Research at the Complutense University of Madrid, and the president of the Spanish Statistics and Operations Research Society.
Education and career
Vitoriano, who is Spanish, was born in 1967. She studied mathematics and operations research at the Complutense University of Madrid. Despite difficulties caused by the death of her father in the first year of her studies, the need to support herself through private tutoring, and the birth of two children during her studies, she earned a bachelor's degree there in 1990 and completed her Ph.D. in 1994.
She became an assistant professor in the Department of Statistics and Operational Research at the Complutense University of Madrid from 1990 to 1997. In 1995, when she traveled to El Salvador as part of an international collaboration to set up a master's program there, and witnessed the devastation and poverty caused in part by the recently ended Salvadoran Civil War. From 1997 to 2006 she worked as an assistant and then associate professor in the Department of Industrial Organisation and Institute for Technological Research at Comillas Pontifical University in Madrid, a private Jesuit school conflicting with her belief in public education, but with an emphasis on social justice that fit well with her research agenda. It was during this time that she changed her research focus from the management of electrical grids to disaster relief. She returned to Complutense University as an untenured associate professor in 2006, and was granted tenure in 2009.
In 2021, she was elected president of the Spanish Statistics and Operations Research Society for a three-year term, beginning in 2022.
Selected publications
References
External links
Home page
1967 births
Living people
Spanish mathematicians
Spanish women mathematicians
Applied mathematicians
Academic staff of the Complutense University of Madrid
Academic staff of Comillas Pontifical University
Complutense University of Madrid alumni | Begoña Vitoriano | [
"Mathematics"
] | 407 | [
"Applied mathematics",
"Applied mathematicians"
] |
73,404,749 | https://en.wikipedia.org/wiki/Sea%20ice%20brine%20pocket | A sea ice brine pocket is an area of fluid sea water with a high salt concentration trapped in sea ice as it freezes. Due to the nature of their formation, brine pockets are most commonly found in areas below , where it is sufficiently cold for seawater to freeze and form sea ice. Though the high salinity and low light conditions of brine pockets create a challenging environment for marine mammals, brine pockets serve as a habitat for various microbes. Sampling and studying these pockets requires specialized equipment to accommodate the hypersaline conditions and subzero temperatures.
Formation
Brine pockets and channels are formed as seawater freezes, through a process called brine rejection. When sea ice forms, the water molecules form ice crystals, which have a regular lattice structure. The larger salt (NaCl) molecules in the sea water cannot be incorporated into this lattice, resulting in the salt being rejected from the sea ice. As seawater freezes and more pure water ice forms, the salt becomes more highly concentrated in the remaining sea water, forming a brine. As the brine salinity increases it becomes more dense compared to the surrounding sea ice, and the brine sinks downward through the ice, forming brine pockets. As the brine pockets form, they begin to coalesce, forming pockets of dense and saline brine. As these larger pockets of brine become interconnected, the may form a network of brine channels within the ice.
Analysis of structure
The internal structure of sea ice can be analyzed using scanning electron microscopy and water-soluble resin. Brine can be drained from the sea ice using centrifugation at sufficiently cold temperatures to prevent melting and to maintain the structural integrity of the sea ice sample. Water-soluble resin is then injected to fill the brine pockets and channels and subsequently polymerized under ultraviolet light at around . The ice is sublimated by freeze drying, freeing the hardened casts, which can be examined using scanning electron microscopes to determine the structure of the brine pockets and channels and the volume of habitable space available to microbes.
Abiotic conditions
Variability
Sea ice brine pockets create diverse and unique microecosystems, with abiotic factors such as chemical composition and physical conditions varying from one pocket to the next. Snow cover and temperature play the most significant role in influencing the variation of conditions present in brine pockets and channels. Sea ice brine pockets in general are extreme environments, due to their subzero temperatures and high salinities, but they harbor a diverse ecosystem of microbial life. Conditions within a brine pocket can vary drastically in a short time with a heavy snowfall or sudden temperature change, which means that microbial life within brine pockets must be flexible to environmental change.
Hypersaline environment
As sea ice forms, the water freezes into a lattice structure; this process ejects many of the salts and microbes from the ice, concentrating them in the remaining water. This high-salinity seawater is known as brine, and as more salts accumulate within the brine pockets, the remaining brine becomes more resistant to freezing. This accumulation of salts, producing a liquid environment that can remain liquid in subzero temperatures, provides a harsh-but-suitable environment for microorganisms to survive. These brine pockets maintain a very saline environment, have high concentrations of other dissolved minerals, and have a high density of microbial life. Brine salinity and concentration are directly dependent on the air temperature of the surrounding environment; as temperatures decrease, more salts become rejected from newly-formed ice, causing more salts to accumulate within the brine, and brine pockets decrease in size. This results in a hypersaline environment with dissolved salt contents which can reach up to 200 g/kg, in contrast to open seawater which has a salinity of 33-37 g/kg.
Light limitation
Brine pockets can form deep within sea ice where there is very low irradiance. Since snow and ice block and reflect incoming light, with deeper brine pockets experience more light limitation than shallower brine pockets. When salts in seawater become rejected during the ice formation, these salts can precipitate and accumulate within the ice, influencing the ability of light to pass through the ice. Given that more salts will precipitate with colder temperatures as brine becomes more concentrated, colder temperatures can result in a greater change to the optics of the ice as more salts accumulate. Lower light levels in brine pockets can impact the survivability of photosynthetic organisms such as cyanobacteria and diatoms. These organisms have developed adaptations so that they can survive in this extremely light-limited environment.
Microbial diversity and abundance
Bacteria
Brine pockets are home to a diverse and dynamic community of marine bacteria which are adapted to survive and thrive in the extreme cold, called psychrophiles. As psychrophiles are adapted to survive and grow at very low temperatures, they are capable of synthesizing enzymes that remain active at low temperatures, allowing them to metabolize in the extremely cold conditions of brine pockets and channels. Bacteria in brine pockets must also be able to tolerate high salt concentrations, so these bacteria are also halophilic. Halophilic psychrophiles are found within Proteobacteria, Actinobacteria and Bacteroidetes.
Two Proteobacteria found to be abundant in brine pockets are gammaproteobacteria and alphaproteobacteria. Many gammaproteobacteria are capable of degrading organic matter, making them important for nutrient cycling and organic matter turnover within the brine pocket. For example, aerobic anoxygenic phototrophic (AAP) bacteria are found in marine environments and play a vital role in supporting the electron transport chain by metabolizing bacteriochlorophyll. Alphaproteobacteria include species that are known to be important for nitrogen cycling and carbon cycling in marine environments. Some Alphaproteobacteria are capable of nitrogen fixation, which can provide an important source of nitrogen for other microorganisms within the pocket.
Actinobacteria are also halophilic psyschrophiles that have been found in brine pockets, known for their ability to produce a wide range of secondary metabolites, including antibiotics and other bioactive compounds. Actinobacteria are often found in association with other microorganisms, where they may play a role in protecting their host from pathogens or other threats.
Lastly, bacteroidetes are found to be abundant in brine pockets, as they can degrade complex organic matter, including carbohydrates and proteins, such as algae-derived ocean polysaccharides. Compared to other bacteria, bacteroidetes species have been shown to contain more genes associated with polysaccharide degradation, allowing them to play a major contributing role in brine pocket carbon- and nutrient-cycling.
Viruses
Brine pockets can support a wide variety of bacteria, and they are also home to high concentrations of marine viruses. Marine viruses in brine pockets may play a major role in regulating the population dynamics of their hosts and influencing biogeochemical cycles within the pocket. As viruses are highly specific to their hosts, viruses in brine pockets include bacteriophages, which infect bacteria, and archaeal viruses, which infect archaea. Algal viruses and other eukaryotic viruses can also be present in brine pockets, which influences the productivity and diversity of these microorganisms. Marine viruses in brine pockets can also influence biogeochemical processes by releasing nutrients through the lysis of infected cells, and by facilitating horizontal gene transfer between hosts. Infections caused by viruses can also trigger changes in the host metabolism, leading to altered nutrient uptake and production of metabolites, which in turn can influence the surrounding environment.
The few studies on viral abundance and composition in brine pockets focus mainly on the diverse concentrations of viruses, separated by molecular size. Brine pockets in the Antarctic lakes have been found to have three groups of viruses at different abundances. In the Arctic waters, viral concentrations were found to vary from 1.6 to 82 × 106 ml−1, with the highest concentrations found in the coldest brine pockets (–24 to –31 °C).
Protists
Brine pockets harbor a diverse and abundant array of protists that are able to survive in extreme conditions. The most common protists in sea ice are pennate diatoms, which can accumulate in numbers so high that sea ice is visibly discolored brown. Sea ice pennate diatom populations can become very dense, reaching up to 1000 μg of chlorophyll per liter of seawater, compared to a typical maximum of 5 μg/L in the open ocean. Due to their high abundance in sea ice, pennate diatoms can profoundly impact the microecosystem within a brine pocket, such as DMSP production. Although diatoms themselves are not high producers of DMSP overall, because of their high abundance within sea ice, the amount of DMSP produced within sea ice as a cryoprotectant and osmoregulator can be impactful.
In addition to pennate diatoms, brine pockets and channels house a variety of flagellates, amoebae, and ciliates. Protist abundance and diversity within a brine pocket/channel is primarily limited to brine pocket/channel structure. Specifically, the size of pores and channels within the ice can limit or encourage the distribution of certain protists and metazoans, with some areas with larger pore sizes having greater abundances of large predatory protists such as ciliates, and other areas with reduced populations of predatory protists due to smaller pore sizes. Brine pockets which are accessed by smaller pores can experience a higher abundance of photoautotrophic protists as well as smaller heterotrophic protists due to limited grazing pressure by the reduced abundance of large predators, such as large ciliates and metazoan predators.
High population densities
Since sea ice pockets are confined and highly-concentrated ecosystems, they are able to house several orders of magnitude greater population densities of bacteria and protists than are found in the open ocean (up to thousands of individuals per liter for protists). This high abundance of organisms can pose challenges, as different bacteria and protists will compete for resources. A high density of microorganisms can result in the accumulation of metabolic byproducts, such as oxygen, dissolved organic matter, ammonia, and dimethylsulfoniopropionate (DMSP). Some organisms can gain a selective advantage within brine pockets as the high population density can result in increased rates of horizontal gene transfer because organisms are in close proximity. Horizontal gene transfer can allow certain organisms to obtain genes from bacteria that may be advantageous in a light-limited, extremely cold environment.
Microbial adaptations
Survival in sea ice brine pockets and channels, which are freezing, hypersaline, and light-limited environments, requires organisms to adapt well to these conditions. Photosynthetic protists and cyanobacteria need to be able to produce energy through alternate metabolic pathways when light is limited within brine pockets. Sea ice brine pockets in Arctic and Antarctic sea ice sheets will experience several weeks of no light at certain locations. In addition to sea ice and snow blocking light from entering brine pockets, seasonal variations of light levels can result in brine pockets being extremely light-limited at times. Sea ice diatoms can alter their metabolic and photosynthetic pathways to survive during periods of little-to-no light. Such adaptations include developing flexible photosystems and altering photosynthetic pigment compositions to allow diatoms to photoacclimate and maintain high photosynthetic efficiency when light levels are low. Sea ice diatoms also have the ability to upregulate and downregulate proteins required for photosynthesis rapidly as light levels change, which helps them survive the environmental stresses of becoming trapped in sea ice and being released back into the ocean as ice melts. Additionally, sea ice microalgae (photosynthetic protists) may be mixotrophic, allowing them to switch to heterotrophy when light is limited. Some research has shown that sea ice diatoms can use an ancient bacterial metabolic pathway known as the Entner−Doudoroff pathway (EDP) to maintain metabolism and energy production during light limitation.
The ability of diatoms to use light for energy also depends on air temperature. As it gets colder, the thylakoid membranes within the microalgae plastids can become dense and compact, which influences how certain photosynthetic proteins (such as the proteins necessary for Photosystems I & II) function and self-assemble. Sea ice diatoms can alter the saturation of the fatty acids that compose the thylakoid membranes as temperatures decrease, which can provide more fluidity to these membranes and result in proper folding of photosynthetic proteins at subzero temperatures.
As temperatures within brine pockets decrease, organisms that survive within brine pockets produce substances that can help prevent freezing. Some sea ice diatoms can produce specialized ice-binding proteins and extracellular polymeric substances, which can help increase the habitat space available within a brine pocket by preventing ice formation and reducing the freezing temperature of the brine. Decreased temperatures can also reduce the efficiency of important physiological processes within many microorganisms. Psychrophilic diatoms and bacteria have the ability to regulate their production of proteins, DNA, and enzymes required for metabolism to help maintain metabolic efficiency in colder temperatures. In the same way that diatoms can regulate the fatty acid composition within their plastid membranes, they can also regulate the plasma membranes surrounding each cell. As temperatures decrease, membranes become less fluid. Both bacteria and sea ice diatoms can alter the fatty acid composition within their membranes to include more unsaturated fatty acids, which allow the plasma membrane to maintain fluidity in extreme cold temperatures.
Sampling
Melted sample analysis
Methods used to study larger eukaryotes present in sea ice are also used to study other smaller microbes. Regardless of sea ice type, standard practice has been to eventually melt the collected sea ice sample before analysis for convenience. Analytical methods developed to investigate pelagic microbes can readily be applied to these melted sea ice samples. One drawback of this approach is that melting the sea ice exposes microbes accustomed to the hypersaline conditions of brine pockets and channels to significantly fresher water. The melting sea ice contains little-to-no salt, greatly diluting the salt concentration of the liquid phase of the sea ice sample. Osmotic shock and lysis may occur if the salinity decreases too much; additionally, careless warming of the sea ice sample may cause the microbes present to undergo thermal shock. One solution has been to melt the ice into a known volume of seawater kept at subzero temperatures filtered by pelagic microbes. This minimizes the decrease in salinity and drop in temperature and subsequently minimizes the loss of live microbes in the sample. Ice samples colder than –10 °C, however, will still see the loss of over half of the microbial population in the sample when using this approach. Colder ice samples will have brine pools with microbe populations that are adapted to significantly greater salinity and much colder temperatures than underlying seawater, requiring them to be melted into sterile brine solutions that match their further elevated salinity and even lower temperatures prior to analysis.
Unmelted sample analysis
Methods to analyze the microbe populations of colder, unmelted ice samples (cold enough to prevent brine drainage) under microscopes were developed by designing specialized equipment. Epifluorescence microscopes that can operate at subzero temperatures allowed researchers to observe undisturbed brine pool microbe populations with the addition of DAPI (DNA staining 4’, 6-diamidino-2-phenylindole) mixed into an adequately salty and cold brine solution to highlight non-autofluorescing microbes. Alternatively, a microscope with a cold stage, commonly used to study glacial ice, may also be used to study unmelted sea ice with the right modifications.
Other stains such as Alcian Blue (stains extracellular polysaccharide substances) and CTC (stains oxygen-respiring bacteria, 5-cyano-2,3-ditolyl tetrazolium) have also been used. Alcian Blue stains have revealed that extracellular polymeric substances (EPS) are ubiquitous throughout brine pools found in sea ice, even without any microbes visible in the brine pool. Some EPS originates from seawater before freezing but is also produced in copious amounts within algal bands and by bacteria to a lesser extent but throughout the entirety of the sea ice. CTC stains have indicated greater percentages of microbial activity within the sea ice when compared to the seawater below it, especially bacteria associated with particulate matter.
CTC has also been applied to the staining of unmelted sections of sea ice sampled during spring and summer, which were subsequently returned to the ice core holes they were collected from for in situ incubation. After recollection, metabolic activity was halted by adding a fixative into the melting sea ice. DAPI and Alcian Blue were then used to stain subsamples of the resulting melted sea ice sample, bypassing the restrictive temperature requirement. It was found that gel-like particles of EPS associated with bacteria were in situ bacterial activity hotspots.
Extracellular enzyme activity has been detected down to as low as –18 °C in unmelted sea ice using a fluorescently-labeled protein substrate analogue. Relying on melted sea ice samples runs the risk of underestimating in situ activity due to the dilution of microbial populations.
Direct collection
A thick portion of sea ice is partially drilled into to create a hole that is covered and left to accumulate draining brine at the bottom before being collected later. This brine drainage occurs much more slowly as temperatures decrease, especially below –5 °C, which is the limit for bulk ice permeability. One limitation to this method is that the origins of the drained brine, as well as what proportion of microbes were left behind in the brine pool, cannot be known with certainty. Studies on these “sackhole” brines have illustrated that substantial bacteria and viruses can be found within brine pools.
References
Wikipedia Student Program
Sea ice | Sea ice brine pocket | [
"Physics"
] | 3,873 | [
"Physical phenomena",
"Earth phenomena",
"Sea ice"
] |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.