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|---|---|---|---|---|---|---|
58,506,310 | https://en.wikipedia.org/wiki/Lynestrenol%20phenylpropionate | Lynestrenol phenylpropionate (LPP), also known as ethynylestrenol phenylpropionate, is a progestin and a progestogen ester which was developed for potential use as a progestogen-only injectable contraceptive by Organon but was never marketed. It was assessed at doses of 25 to 75 mg in an oil solution once a month by intramuscular injection. LPP was associated with high contraceptive failure at the low dose and with poor cycle control. The medication was found to produce estrogenic effects in the endometrium in women due to transformation into estrogenic metabolites.
A single intramuscular injection of 50 to 100 mg LPP in oil solution has been found to have a duration of action of 14 to 30 days in terms of clinical biological effect in the uterus and on body temperature in women.
LPP has a long biological half-life in rats when given as an intramuscular depot injection; its half-life was similar to that of nandrolone laurate (nandrolone dodecanoate) and was about 2-fold longer than that of nandrolone decanoate, 10-fold longer than that of lynestrenol and nandrolone phenylpropionate, 50-fold longer than that of progesterone, and 430-fold longer than that of nandrolone.
See also
List of progestogen esters § Esters of 19-nortestosterone derivatives
References
Abandoned drugs
Ethynyl compounds
Anabolic–androgenic steroids
Estranes
Phenylpropionate esters
Prodrugs
Progestogens
Progestogen esters
Synthetic estrogens | Lynestrenol phenylpropionate | [
"Chemistry"
] | 367 | [
"Chemicals in medicine",
"Drug safety",
"Prodrugs",
"Abandoned drugs"
] |
58,506,509 | https://en.wikipedia.org/wiki/Medroxyprogesterone%20caproate | Medroxyprogesterone caproate (MPC) is a progestin and a progestogen ester which was synthesized in 1958 but was never marketed. It has been confused with hydroxyprogesterone caproate (OHPC) and medroxyprogesterone acetate (MPA) in a number of publications. In addition to MPA and OHPC, analogues of MPC include chlormadinone caproate, gestonorone caproate, megestrol caproate, and methenmadinone caproate.
See also
List of progestogen esters § Esters of 17α-hydroxyprogesterone derivatives
References
Abandoned drugs
Caproate esters
Diketones
Pregnanes
Progestogen esters
Progestogens | Medroxyprogesterone caproate | [
"Chemistry"
] | 174 | [
"Drug safety",
"Abandoned drugs"
] |
58,506,604 | https://en.wikipedia.org/wiki/Pharmacy%20Act%201852 | The Pharmacy Act 1852 (15 & 16 Vict. c. 56) was the first legislation in the United Kingdom to regulate pharmacists and druggists.
It set up a register of pharmacists and limited the use of the title to people registered with the Pharmaceutical Society, but proposals to give the society exclusive rights to sell drugs or poisons were rejected. It did not provide a legal definition for the trade and practice of pharmacy.
Notes
United Kingdom Acts of Parliament 1852
Drug control law in the United Kingdom
Substance dependence
Pharmacy in the United Kingdom | Pharmacy Act 1852 | [
"Chemistry"
] | 114 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
58,506,657 | https://en.wikipedia.org/wiki/Bromethenmadinone%20acetate | Bromethenmadinone acetate (BMMA, also known as bromsuperlutin) is a progestin medication which was developed in Czechoslovakia and was described in 1970 but was never marketed. Analogues of BMMA include chlormethenmadinone acetate, melengestrol acetate, and methenmadinone acetate.
See also
List of progestogen esters § Esters of 17α-hydroxyprogesterone derivatives
16-Methylene-17α-hydroxyprogesterone acetate
References
Abandoned drugs
Acetate esters
Brominated steroids
Enones
Diketones
Pregnanes
Progestogen esters
Progestogens
Veterinary drugs
Vinylidene compounds | Bromethenmadinone acetate | [
"Chemistry"
] | 152 | [
"Drug safety",
"Abandoned drugs"
] |
58,507,090 | https://en.wikipedia.org/wiki/Blazegraph | Blazegraph is an open source triplestore and graph database, written in Java. It has been abandoned since 2020 and is known to be used in production by WMDE for the Wikidata SPARQL endpoint. It is licensed under the GNU GPL (version 2).
Amazon acquired the Blazegraph developers and the Blazegraph open source development was essentially stopped in April 2018.
Early history
The system was first known as Bigdata. Since release of version 1.5 (12 February 2015), it is named Blazegraph.
Prominent users
The Wikimedia Foundation uses Blazegraph for the Wikidata Query Service, which is a SPARQL endpoint.
Sophox, a fork of the Wikidata Query Service, specializes in OpenStreetMap queries.
The Datatourisme project uses Blazegraph as the database platform; however, GraphQL is used as the query language instead of SPARQL.
Notable features
RDF* — an alternative approach to RDF reification, which gives RDF graphs capabilities of graphs;
as the consequence of the previous, ability of querying graphs both in SPARQL and Gremlin;
as an alternative to Gremlin querying, abstraction over RDF graphs support in SPARQL;
The SERVICE syntax of federated queries for functionality extending;
Managed behavior of the query plan generator;
Reusable named subqueries.
Acqui-hiring by Amazon Web Service (AWS)
It was alleged
that Amazon Neptune is based on Blazegraph, as evidenced by:
acquiring of the Blazegraph trademark by AWS;
acquiring of the blazegraph.com domain name by AWS;
transition of many employees (including CEO) to AWS.
References
External links
Page on DB-Engines.com
Graph databases
Triplestores
Semantic Web | Blazegraph | [
"Mathematics"
] | 377 | [
"Graph databases",
"Mathematical relations",
"Graph theory"
] |
58,507,154 | https://en.wikipedia.org/wiki/Aspergillus%20bicolor | Aspergillus bicolor is a species of fungus in the genus Aspergillus. It is from the Aenei section. The species was first described in 1978. It has been reported to produce sterigmatocystin, versicolorins, and some anthraquinones.
Growth on agar plates
Apsergillus bicolor has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
bicolor
Fungi described in 1978
Fungus species | Aspergillus bicolor | [
"Biology"
] | 133 | [
"Fungi",
"Fungus species"
] |
58,507,168 | https://en.wikipedia.org/wiki/C18H19NO | {{DISPLAYTITLE:C18H19NO}}
The molecular formula C18H19NO (molar mass: 265.356 g/mol) may refer to:
Nordoxepin
HP-505
Molecular formulas | C18H19NO | [
"Physics",
"Chemistry"
] | 49 | [
"Molecules",
"Set index articles on molecular formulas",
"Isomerism",
"Molecular formulas",
"Matter"
] |
58,507,179 | https://en.wikipedia.org/wiki/Aspergillus%20crustosus | Aspergillus crustosus is a species of fungus in the genus Aspergillus. It is from the Aenei section. The species was first described in 1965. It has been reported to produce PR-toxin.
Growth and morphology
A. crustosus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
crustosus
Fungi described in 1965
Fungus species | Aspergillus crustosus | [
"Biology"
] | 115 | [
"Fungi",
"Fungus species"
] |
58,507,200 | https://en.wikipedia.org/wiki/Gearspace | Gearspace is a website and forum dedicated to audio engineering. Gearspace is one of the largest resources for pro audio information, with over 1.6 million monthly visitors from 218 countries. Originally established in 2002 as Gearslutz, the site rebranded in March 2021.
History
In 2002, Julian Standen and Meg Lee Chin, both musicians and audio engineers, created the site, which is widely regarded as a top online resource for music production knowledge and discussion. The site has been described as the "best place … for help with your interface, DAW, signal path, or just about anything else."
In 2018, the website was ranked by Alexa.com as the 7,360th most popular website in the world. In 2020, it had over 1.6 million monthly visitors from 218 countries.
Behringer Lawsuit
In mid-2017, Music Tribe, the parent company of music equipment manufacturer Behringer, pursued legal action against synthesizer manufacturer Dave Smith Instruments (DSI) and a number of the website's forum participants, including a DSI employee, for defamation over various statements made in forum discussions that alleged that Behringer copies other companies' products and exhibits other questionable business practices.
Name change
On January 6, 2021, a forum user started an online petition at Change.org encouraging the website to change its name from Gearslutz. Site co-founder Standen announced later the same month that the site would be undergoing a name change, stating "the word-play pun in the name has gotten old and it is now time to move forward".
On March 29, 2021, Standen confirmed that the site would be renamed "Gearspace.com".
References
British music websites
Audio engineering | Gearspace | [
"Engineering"
] | 346 | [
"Electrical engineering",
"Audio engineering"
] |
58,507,246 | https://en.wikipedia.org/wiki/Aspergillus%20discophorus | Aspergillus discophorus is a species of fungus in the genus Aspergillus. It is from the Aenei section. The species was first described in 2008. It has been isolated from soil in Spain.
Growth and morphology
A. discophorus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
discophorus
Fungi described in 2008
Fungus species | Aspergillus discophorus | [
"Biology"
] | 114 | [
"Fungi",
"Fungus species"
] |
58,507,279 | https://en.wikipedia.org/wiki/Aspergillus%20heyangensis | Aspergillus heyangensis is a species of fungus in the genus Aspergillus. It is from the Aenei section. The species was first described in 1994. It has been reported to produce a decaturin.
Growth and morphology
A. heyangensis has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
heyangensis
Fungi described in 1994
Fungus species | Aspergillus heyangensis | [
"Biology"
] | 115 | [
"Fungi",
"Fungus species"
] |
58,507,417 | https://en.wikipedia.org/wiki/Aspergillus%20brunneus | Aspergillus brunneus is a species of fungus in the genus Aspergillus. It is from the Aspergillus section. The species was first described in 1893. It has been reported to produce asperflavin, asperentins, auroglaucin, bisanthrons, dihydroauroglaucin, echinulins, 5-farnesyl-5,7-dihydroxy-4-methylphthalide, erythroglaucin, flavoglaucin, isoechinulins, mycophenolic acid, neoechinulins, physcion, questin, tetracyclic, and tetrahydroauroglaucin.
Growth and morphology
A. brunneus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
brunneus
Fungi described in 1893
Fungus species | Aspergillus brunneus | [
"Biology"
] | 227 | [
"Fungi",
"Fungus species"
] |
58,507,434 | https://en.wikipedia.org/wiki/Aspergillus%20cibarius | Aspergillus cibarius is a species of fungus in the genus Aspergillus. It is from the Aspergillus section. The species was first described in 2012. It has been reported to produce asperflavin, auroglaucin, bisanthrons, dihydroauroglaucin, echinulins, emodin, erythroglaucin, flavoglaucin, neoechinulins physcion, tetracyclic, and tetrahydroauroglaucin.
Growth and morphology
A. cibarius has been cultivated on both Czapek yeast extract agar (CYA) plates and yeast extract sucrose agar (YES) plates. The growth morphology of the colonies can be seen in the pictures below.
References
cibarius
Fungi described in 2012
Fungus species | Aspergillus cibarius | [
"Biology"
] | 181 | [
"Fungi",
"Fungus species"
] |
58,507,456 | https://en.wikipedia.org/wiki/Aspergillus%20costiformis | Aspergillus costiformis is a species of fungus in the genus Aspergillus. It is from the Aspergillus section. The species was first described in 1995. It has been reported to produce auroglaucin, dihydroauroglaucin, echinulins, epiheveadrides, flavoglaucin, isoechinulins, neoechinulins, physcion, and tetrahydroauroglaucin.
References
costiformis
Fungi described in 1995
Fungus species | Aspergillus costiformis | [
"Biology"
] | 114 | [
"Fungi",
"Fungus species"
] |
58,507,473 | https://en.wikipedia.org/wiki/Aspergillus%20cumulatus | Aspergillus cumulatus is a species of fungus in the genus Aspergillus. It is from the Aspergillus section. The species was first described in 2014. It has been reported to produce auroglaucin, bisanthrons, dihydroauroglaucin, echinulins, emodin, erythroglaucin, flavoglaucin, isoechinulins, neoechinulins, physcion, tetracyclic, and tetrahydroauroglaucin.
References
cumulatus
Fungi described in 2014
Fungus species | Aspergillus cumulatus | [
"Biology"
] | 129 | [
"Fungi",
"Fungus species"
] |
58,507,498 | https://en.wikipedia.org/wiki/Aspergillus%20endophyticus | Aspergillus endophyticus is a species of fungus in the genus Aspergillus, section Aspergillus. It was isolated as an endophyte of Acer pseudoplatanus in the Czech Republic.
The identified extrolites produced by A. endophyticus include auroglaucin, bisanthrons, dihydroauroglaucin, echinulins, emodin, erythroglaucin, flavoglaucin, isoechinulins, neoechinulins, physcion, and tetrahydroauroglaucin.
Growth and morphology
A. endophyticus has been cultivated on both yeast extract sucrose agar (YES) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
endophyticus
Fungi described in 2017
Fungus species | Aspergillus endophyticus | [
"Biology"
] | 198 | [
"Fungi",
"Fungus species"
] |
58,507,527 | https://en.wikipedia.org/wiki/Aspergillus%20intermedius | Aspergillus intermedius is a species of fungus in the genus Aspergillus. It is from the Aspergillus section. The species was first described in 1975. It has been reported to produce asperflavin, auroglaucin, dihydroauroglaucin, echinulins, epiheveadrides, flavoglaucin, isoechinulins, LL-S491β, neoechinulins, physcion, questin, and tetrahydroauroglaucin.
Growth and morphology
A. intermedius has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
intermedius
Fungi described in 1975
Fungus species | Aspergillus intermedius | [
"Biology"
] | 186 | [
"Fungi",
"Fungus species"
] |
58,507,539 | https://en.wikipedia.org/wiki/Feldman%E2%80%93H%C3%A1jek%20theorem | In probability theory, the Feldman–Hájek theorem or Feldman–Hájek dichotomy is a fundamental result in the theory of Gaussian measures. It states that two Gaussian measures and on a locally convex space are either equivalent measures or else mutually singular: there is no possibility of an intermediate situation in which, for example, has a density with respect to but not vice versa. In the special case that is a Hilbert space, it is possible to give an explicit description of the circumstances under which and are equivalent: writing and for the means of and and and for their covariance operators, equivalence of and holds if and only if
and have the same Cameron–Martin space ;
the difference in their means lies in this common Cameron–Martin space, i.e. ; and
the operator is a Hilbert–Schmidt operator on
A simple consequence of the Feldman–Hájek theorem is that dilating a Gaussian measure on an infinite-dimensional Hilbert space (i.e. taking for some scale factor ) always yields two mutually singular Gaussian measures, except for the trivial dilation with since is Hilbert–Schmidt only when
See also
References
Probability theorems
Theorems in measure theory | Feldman–Hájek theorem | [
"Mathematics"
] | 246 | [
"Theorems in mathematical analysis",
"Theorems in measure theory",
"Theorems in probability theory",
"Mathematical problems",
"Mathematical theorems"
] |
58,507,548 | https://en.wikipedia.org/wiki/Aspergillus%20leucocarpus | Aspergillus leucocarpus is a species of fungus in the genus Aspergillus. It is from the Aspergillus section. The species was first described in 1969. It has been reported to produce an apolar indoloterpene, echinulins, epiheveadrides, and neoechinulins.
References
leucocarpus
Fungi described in 1969
Fungus species | Aspergillus leucocarpus | [
"Biology"
] | 88 | [
"Fungi",
"Fungus species"
] |
58,507,576 | https://en.wikipedia.org/wiki/Aspergillus%20mallochii | Aspergillus mallochii is a species of fungus in the genus Aspergillus. It is from the Aspergillus section. The species was first described in 2017. It has been reported to produce auroglaucin, dihydroauroglaucin, echinulins, erythroglaucin, flavoglaucin, isoechinulins, neoechinulins, tetracyclic, and tetrahydroauroglaucin.
Growth and morphology
A. mallochii has been cultivated on both Czapek yeast extract agar (CYA) plates and yeast extract sucrose agar (YES) plates. The growth morphology of the colonies can be seen in the pictures below.
References
mallochii
Fungi described in 2017
Fungus species | Aspergillus mallochii | [
"Biology"
] | 169 | [
"Fungi",
"Fungus species"
] |
58,507,605 | https://en.wikipedia.org/wiki/Aspergillus%20megasporus | Aspergillus megasporus is a species of fungus in the genus Aspergillus. It is from the Aspergillus section. The species was first described in 2017. It has been reported to produce asperflavin, auroglaucin, bisanthrons, dihydroauroglaucin, echinulin, emodin, erythroglaucin, flavoglaucin, isoechinulins, neoechinulins, preechinulin, physcion, quinolactacin (A1, A2, B), tetracyclic, and tetrahydroauroglaucin.
Growth and morphology
Aspergillus megasporus has been cultivated on both yeast extract sucrose agar (YES) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
megasporus
Fungi described in 2017
Fungus species | Aspergillus megasporus | [
"Biology"
] | 208 | [
"Fungi",
"Fungus species"
] |
58,507,625 | https://en.wikipedia.org/wiki/Aspergillus%20montevidensis | Aspergillus montevidensis is a species of fungus in the genus Aspergillus. It is from the Aspergillus section. The species was first described in 1931. It has been reported to produce apolar indoloterpenes, asperflavin in few isolates, auroglaucin, dihydroauroglaucin, echinulins, epiheveadrides, flavoglaucin, isoechinulins, neoechinulins, and tetrahydroauroglaucin.
Growth and morphology
A. montevidensis has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
montevidensis
Fungi described in 1931
Fungus species | Aspergillus montevidensis | [
"Biology"
] | 184 | [
"Fungi",
"Fungus species"
] |
58,507,643 | https://en.wikipedia.org/wiki/Aspergillus%20neocarnoyi | Aspergillus neocarnoyi is a species of fungus in the genus Aspergillus. It is from the Aspergillus section. The species was first described in 1989. It has been reported to produce asperentins, asperflavin, auroglaucin, a bisanthron, dihydroauroglaucin, echinulins, flavoglaucin, neoechinulins, questin, questinol, tetracyclic, and tetrahydroauroglaucin.
Growth and morphology
A. neocarnoyi has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
neocarnoyi
Fungi described in 1989
Fungus species | Aspergillus neocarnoyi | [
"Biology"
] | 186 | [
"Fungi",
"Fungus species"
] |
58,507,670 | https://en.wikipedia.org/wiki/Aspergillus%20niveoglaucus | Aspergillus niveoglaucus is a species of fungus in the genus Aspergillus. It is from the Aspergillus section. The species was first described in 1941. It has been reported to produce asperflavin, auroglaucin, bisanthrons, dihydroauroglaucin, echinulins, emodin, erythroglaucin, flavoglaucin, mycophenolic acid (tentatively identified), neoechinulins, physcion, questin, questinol, siderin, tetracyclic, and tetrahydroauroglaucin.
References
neniveoglaucus
Fungi described in 1941
Taxa named by Charles Thom
Fungus species | Aspergillus niveoglaucus | [
"Biology"
] | 160 | [
"Fungi",
"Fungus species"
] |
58,507,732 | https://en.wikipedia.org/wiki/Aspergillus%20pseudoglaucus | Aspergillus pseudoglaucus is a species of fungus in the genus Aspergillus. It is from the Aspergillus section. The species was first described in 1929. It has been reported to produce asperentins, asperflavin, auroglaucin, bisanthrons, dihydroauroglaucin, echinulins, erythroglaucin, 6-farnesyl-5,7-dihydroxy-4-methylphthalide, flavoglaucin, isoechinulins, mycophenolic acid, neoechinulins, physcion, questin, questinol, tetracyclic, and tetrahydroauroglaucin.
Growth and morphology
A. pseudoglaucus has been cultivated on both Czapek yeast extract agar (CYA) plates and yeast extract sucrose agar (YES) plates. The growth morphology of the colonies can be seen in the pictures below.
References
pseudoglaucus
Fungi described in 1929
Fungus species | Aspergillus pseudoglaucus | [
"Biology"
] | 228 | [
"Fungi",
"Fungus species"
] |
58,507,757 | https://en.wikipedia.org/wiki/Aspergillus%20sloanii | Aspergillus sloanii is a species of fungus in the genus Aspergillus. It is from the Aspergillus section. The species was first described in 2014. It has been reported to produce auroglaucin, bisanthrons, dihydroauroglaucin, echinulins, flavoglaucin, physcion, tetracyclic, and tetrahydroauroglaucin.
Growth and morphology
A. sloanii has been cultivated on both Czapek yeast extract agar (CYA) plates and yeast extract sucrose agar (YES) plates. The growth morphology of the colonies can be seen in the pictures below.
References
sloanii
Fungi described in 2014
Fungus species | Aspergillus sloanii | [
"Biology"
] | 156 | [
"Fungi",
"Fungus species"
] |
58,507,778 | https://en.wikipedia.org/wiki/Aspergillus%20teporis | Aspergillus teporis is a species of fungus in the genus Aspergillus. It is from the Aspergillus section. The species was first described in 2017. It has been reported to produce echinulins, epiheveadrides, isoechinulins, and neoechinulins.
Growth and morphology
A. teporis has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
teporis
Fungi described in 2017
Fungus species | Aspergillus teporis | [
"Biology"
] | 137 | [
"Fungi",
"Fungus species"
] |
58,507,792 | https://en.wikipedia.org/wiki/Aspergillus%20tonophilus | Aspergillus tonophilus is a species of fungus in the genus Aspergillus. It is from the Aspergillus section. The species was first described in 1962. It has been reported to produce auroglaucin, bisanthrons, dihydroauroglaucin, echinulins, flavoglaucin, an apolar indoloterpene, isoechinulins, neoechinulins, and tetrahydroauroglaucin.
Growth and morphology
A. tonophilus has been cultivated on both yeast extract sucrose agar (YES) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
tonophilus
Fungi described in 1962
Fungus species | Aspergillus tonophilus | [
"Biology"
] | 174 | [
"Fungi",
"Fungus species"
] |
58,507,832 | https://en.wikipedia.org/wiki/Aspergillus%20umbrosus | Aspergillus umbrosus (also named A. glaucus) is a species of fungus in the genus Aspergillus. It is from the Aspergillus section. The species was first described in 1912. It has been reported to produce asperflavin, auroglaucin, bisanthrons, dihydroauroglaucin, echinulins, emodin, epiheveadrides, erythroglaucin, flavoglaucin, isoechinulins, neoechinulins, physcion, questin, questinol, tetracyclic, and tetrahydroauroglaucin.
References
umbrosus
Fungi described in 1912
Fungus species | Aspergillus umbrosus | [
"Biology"
] | 158 | [
"Fungi",
"Fungus species"
] |
58,507,887 | https://en.wikipedia.org/wiki/Aspergillus%20zutongqii | Aspergillus zutongqii is a species of fungus in the genus Aspergillus. It is from the Aspergillus section. The species was first described in 2017. It has been reported to produce asperflavin, auroglaucin, bisanthrons, dihydroauroglaucin, echinulins, emodin, epiheveadrides, erythroglaucin, flavoglaucin, isoechinulins, neoechinulins, and tetrahydroauroglaucin.
Growth and morphology
A. zutongqii has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
zutongqii
Fungi described in 2017
Fungus species | Aspergillus zutongqii | [
"Biology"
] | 194 | [
"Fungi",
"Fungus species"
] |
58,508,059 | https://en.wikipedia.org/wiki/Testosterone%20propionate/testosterone%20phenylpropionate/testosterone%20isocaproate | Testosterone propionate/testosterone phenylpropionate/testosterone isocaproate (TP/TPP/TiC), sold under the brand name Sustanon 100 (Organon), is an injectable combination medication of three testosterone esters, all of which are androgens/anabolic steroids. They include:
20 mg testosterone propionate
40 mg testosterone phenylpropionate
40 mg testosterone isocaproate
They are provided as an oil solution and are administered by intramuscular injection. The different testosterone esters provide for different elimination half-lives in the body. Esterification of testosterone provides for a sustained but non-linear release of testosterone hormone from the injection depot into the circulation.
The medication was a smaller dose than Sustanon 250 and was usually reserved for pediatric use.
Sustanon 100 has not been produced since 2009. Sustanon 100 is manufactured in India by Zydus.
See also
Testosterone propionate/testosterone phenylpropionate/testosterone isocaproate/testosterone decanoate
Testosterone propionate/testosterone phenylpropionate/testosterone isocaproate/testosterone caproate
List of combined sex-hormonal preparations § Androgens
References
Abandoned drugs
Anabolic–androgenic steroids
Androstanes
Combined androgen formulations
Testosterone esters
Testosterone | Testosterone propionate/testosterone phenylpropionate/testosterone isocaproate | [
"Chemistry"
] | 281 | [
"Drug safety",
"Abandoned drugs"
] |
58,508,195 | https://en.wikipedia.org/wiki/Applied%20Inorganic%20Chemistry%20Award | The Applied Inorganic Chemistry Award, established in 2008, is conferred biennially by the Dalton division of the Royal Society of Chemistry for "outstanding contributions to the development of any branch of inorganic chemistry which has an application in industry." The winner gives a lecture tour in the UK, and receives a medal and £2000. The award was discontinued in 2020.
Winners
Source:
See also
List of chemistry awards
References
Awards of the Royal Society of Chemistry
Inorganic chemistry | Applied Inorganic Chemistry Award | [
"Chemistry"
] | 92 | [
"nan"
] |
58,508,500 | https://en.wikipedia.org/wiki/List%20of%20combined%20sex-hormonal%20preparations | This is a list of known combined sex-hormonal formulations. Brand names and developmental code names are in parentheses.
Androgens
Injection
Marketed
Nandrolone decanoate/nandrolone phenylpropionate (Dinandrol)
Testosterone propionate/testosterone isocaproate/testosterone caproate (Androteston PP)
Testosterone propionate/testosterone enanthate/testosterone undecylenate (Durasteron)
Testosterone propionate/testosterone enanthate (Testoviron Depot)
Testosterone propionate/testosterone ketolaurate (Testosid Depot)
Testosterone propionate/testosterone phenylpropionate/testosterone isocaproate (Sustanon 100)
Testosterone propionate/testosterone phenylpropionate/testosterone isocaproate/testosterone caproate (Omnadren 250)
Testosterone propionate/testosterone phenylpropionate/testosterone isocaproate/testosterone decanoate (Sustanon 250)
Testosterone propionate/testosterone valerate/testosterone undecylenate (Triolandren)
Testosterone propionate/testosterone cypionate/prasterone (Sten)
Veterinary
Marketed
Boldenone acetate/boldenone cypionate/boldenone propionate/boldenone undecylenate (Equilon 100)
Testosterone acetate/testosterone undecanoate/testosterone valerate (Deposterona)
Estrogens
Oral
Marketed
Conjugated estriol (Emmenin, Progynon)
Conjugated estrogens (Premarin)
Esterified estrogens (Estratab, Menest)
Estradiol/estrone/estriol (Hormonin)
Ethinylestradiol/dienestrol (Foxinette)
Injection
Marketed
Estradiol benzoate/estradiol phenylpropionate (Dimenformon Prolongatum)
Never marketed
Estradiol/estradiol enanthate
Progestogens
Injection
Marketed
Progesterone/hydroxyprogesterone heptanoate/α-tocopherol palmitate (Tocogestan)
Androgens and estrogens
Oral
Marketed
Chlorotrianisene/methyltestosterone (Tace mit Androgen)
Conjugated estrogens/methyltestosterone (Premarin with Methyltestosterone)
Dienestrol/methyltestosterone (Estan, Lucidon)
Dienestrol diacetate/methyltestosterone (Farmatest)
Diethylstilbestrol/methyltestosterone (Tylosterone)
Esterified estrogens/methyltestosterone (Covaryx, Eemt, Essian, Estratest, Menogen, Syntest)
Ethinylestradiol/methyltestosterone (Climatone, Dumone, Duotrone, Estandron, Femandren, Femovirin, Gynetone, Lynandron, Mepilin, Mixogen, Primodian)
Methylestradiol/methyltestosterone (Klimanosid)
Methylestradiol/methyltestosterone/reserpine (Klimanosid R)
Injection
Marketed
Estradiol benzoate/testosterone propionate (Bothermon)
Estradiol benzoate/estradiol dienanthate/testosterone enanthate benzilic acid hydrazone (Climacteron, Lactimex, Lactostat)
Estradiol benzoate/estradiol phenylpropionate/testosterone propionate/testosterone phenylpropionate/testosterone isocaproate (Estandron Prolongatum, Lynandron Prolongatum, Mixogen [Injection])
Estradiol benzoate/testosterone isobutyrate (Femandren M, Folivirin)
Estradiol butyrylacetate/testosterone ketolaurate/reserpine (Klimanosid R-Depot)
Estradiol cypionate/testosterone cypionate (Depo-Testadiol, Femovirin)
Estradiol cypionate/testosterone enanthate (Supligol)
Estradiol valerate/prasterone enanthate (Binodian Depot, Cidodian Depot, Gynodian Depot, Klimax, Supligol NF)
Estradiol valerate/testosterone enanthate (Deladumone, Despamen, Ditate, Ditate-DS, Gravignost, Primodian Depot, Valertest)
Veterinary
Marketed
Diethylstilbestrol/methyltestosterone (Maxymin, Tylosterone)
Diethylstilbestrol/testosterone (Rapigain)
Estradiol benzoate/estradiol enanthate/testosterone enanthate (Uni-Bol)
Estradiol benzoate/testosterone propionate (Component E-H, Implix BF, Progro H, Synovex H)
Ethinylestradiol/methyltestosterone (Taril)
Estrogens and progestogens
Oral
Marketed
In birth control pills:
Drospirenone/estetrol (Nextstellis, Drovelis, Lydisilka)
Estradiol/nomegestrol acetate (Naemis, Zoely)
Estradiol valerate/cyproterone acetate (Femilar)
Estradiol valerate/dienogest (Natazia, Qlaira)
Ethinylestradiol/chlormadinone acetate (Belara)
Ethinylestradiol/cyproterone acetate (Diane, Diane-35)
Ethinylestradiol/desogestrel (Alenvona, Apri, Azurette, Bekyree, Bimizza, Caziant, Cesia, Cimizt, Cyclessa, Cyred, Denise, Desogen, Desirett, Emoquette, Enskyce, Gedarel, Gracial, Isibloom, Juleber, Kalliga, Kariva, Kimidess, Laurina, Linessa, Marvelon, Mercilon, Mircette, Mirvala, Novynette, Ortho-Cept, Pimtrea, Reclipsen, Regulon, Simliya, Solia, Velivet, Viorele, Volnea)
Ethinylestradiol/dienogest (Valette)
Ethinylestradiol/dimethisterone (Oracon)
Ethinylestradiol/drospirenone (Yasmin, Yasminelle, Yaz)
Ethinylestradiol/drospirenone/levomefolic acid (Beyaz, Safyral)
Ethinylestradiol/etynodiol diacetate (Demulen)
Ethinylestradiol/gestodene (Femodene, Femodette, Gynera, Harmonet, Meliane, Minesse, Minulet)
Ethinylestradiol/levonorgestrel (Amethyst, Aviane, Balcoltra, Falmina, Levlen, Lillow, Orsythia, Vienva)
Ethinylestradiol/levonorgestrel/bisglycinate
Ethinylestradiol/levonorgestrel/ferrous fumarate
Ethinylestradiol/lynestrenol (Lyndiol)
Ethinylestradiol/medroxyprogesterone acetate (Gianda, Provest)
Ethinylestradiol/megestrol acetate (Nuvacon, Volidan)
Ethinylestradiol/norethisterone (Brevicon, Norinyl 1+35, Ortho-Novum 7/7/7, Taytulla, Tri-Norinyl, Zenchent)
Ethinylestradiol/norethisterone/ferrous fumarate (Blisovi 24 FE, Estrostep Fe, Femcon FE, Kaitlib FE, Lo Minastrin Fe, Loestrin 24 Fe, Microgestin 24 FE)
Ethinylestradiol/norethisterone acetate (FemHRT)
Ethinylestradiol/norethisterone acetate/ferrous fumarate
Ethinylestradiol/norgestimate (Ortho Tri-Cyclen, Sprintec)
Ethinylestradiol/norgestrel (Ovral)
Ethinylestradiol/norgestrienone (Miniplanor, Planor)
Ethinylestradiol/quingestanol acetate (Riglovis)
Ethinylestradiol sulfonate/norethisterone acetate (Deposiston)
Mestranol/anagestone acetate (Neo-Novum)
Mestranol/chlormadinone acetate (C-Quens, Lutedion)
Mestranol/etynodiol diacetate (Ovulen)
Mestranol/hydroxyprogesterone acetate (Hormolidin)
Mestranol/lynestrenol (Lyndiol)
Mestranol/norethisterone (Norethin, Noriday, Norinyl, Norquen, Ortho-Novum)
Mestranol/noretynodrel (Enavid, Enovid)
Quinestrol/etynodiol diacetate (Soluna)
Quinestrol/levonorgestrel (Yuèkětíng, Àiyuè)
Quinestrol/norgestrel (Compound Norgestrel)
Quinestrol/quingestanol acetate (Unovis)
For menopausal hormone therapy and/or gynecological disorders:
Conjugated estrogens/medrogestone (Presomen)
Conjugated estrogens/medroxyprogesterone acetate (Prempro, Premphase)
Conjugated estrogens/norgestrel (Prempak-C)
Estradiol/drospirenone (Angeliq)
Estradiol/dydrogesterone (Femoston)
Estradiol/gestodene (Avaden, Avadene)
Estradiol/levonorgestrel
Estradiol/medroxyprogesterone acetate (Indivina, Tridestra)
Estradiol/norethisterone acetate (Activella, Activelle, Cliane, Estalis, Eviana, Evorel, Kliogest, Novofem)
Estradiol/norgestimate (Prefest)
Estradiol/progesterone (Bijuva)
Estradiol/trimegestone (Lovelle, Totelle)
Estradiol valerate/cyproterone acetate (Climen, Climen 28)
Estradiol valerate/estriol/levonorgestrel (CycloÖstrogynal)
Estradiol valerate/levonorgestrel (Cyclo-Progynova N)
Estradiol valerate/medroxyprogesterone acetate (Dilena, Divina, Divitren, Farludiol, Indivina, Sisare)
Estradiol valerate/norethisterone (Climagest, Climesse)
Estradiol valerate/norethisterone acetate (Cliovelle, Norestin, Trisequens)
Estradiol valerate/norgestrel (Cyclacur, Cyclocur, Cyclo-Progynova, Postoval, Progyluton)
Ethinylestradiol/ethisterone (Amenorone, Di-Pro, Duosterone, Menstrogen, Oracecron, Orasecron)
Mestranol/noretynodrel (Enovid)
Never or not yet marketed
In birth control pills:
Estradiol/norethisterone (Netagen, Netagen 403)
Transdermal
Marketed
In contraceptive patches:
Ethinylestradiol/norelgestromin (Evra, Ortho Evra, Xulane)
For menopausal hormone therapy:
Estradiol/levonorgestrel (Climara Pro)
Estradiol/norethisterone acetate (CombiPatch)
Vaginal
Marketed
In contraceptive vaginal rings:
Ethinylestradiol/etonogestrel (Circlet, NuvaRing)
Segesterone acetate/ethinylestradiol (Annovera)
Injection
Marketed
In combined injectable contraceptives:
Estradiol/megestrol acetate (Mego-E, Chinese Injectable No. 2)
Estradiol benzoate/estradiol valerate/hydroxyprogesterone caproate (Sin-Ol)
Estradiol benzoate butyrate/algestone acetophenide (Redimen, Soluna, Unijab)
Estradiol cypionate/hydroxyprogesterone caproate (Sinbios)
Estradiol cypionate/medroxyprogesterone acetate (Cyclo-Provera, Cyclofem, Lunelle)
Estradiol enanthate/algestone acetophenide (Anafertin, Deladroxate, Perlutan, Topasel, Yectames)
Estradiol valerate/hydroxyprogesterone caproate (Chinese Injectable No. 1)
Estradiol valerate/norethisterone enanthate (Mesigyna, Mesygest)
For menopausal hormone therapy, gynecological disorders, habitual abortion, and other indications:
Estradiol/progesterone (Juvenum)
Estradiol benzoate/hydroxyprogesterone caproate (Primosiston)
Estradiol benzoate/progesterone (Duogynon, Sistocyclin)
Estradiol dipropionate/hydroxyprogesterone caproate (EP Hormone Depot)
Estradiol hemisuccinate/progesterone (Hosterona)
Estradiol pivalate/progesterone (Estrotate with Progesterone)
Estradiol valerate/hydroxyprogesterone caproate (Gravibinan, Gravibinon)
Estrone/progesterone (Synergon)
Never marketed
In combined injectable contraceptives:
Estradiol/progesterone (in microspheres and macrocrystalline aqueous suspension)
Estradiol undecylate/norethisterone enanthate
Estradiol valerate/megestrol acetate
Estradiol valerate/methenmadinone caproate (Lutofollin)
Polyestradiol phosphate/medroxyprogesterone acetate
Additional preparations listed at Combined injectable birth control § Research
For other indications:
Estradiol valerate/gestonorone caproate (SH-834, SH-8.0834)
Veterinary
Marketed
Estradiol benzoate/progesterone (Component E-S, Implix BM, Synovex C, Synovex S)
Estradiol valerate/norgestomet (Syncro-Mate-B)
Androgens and progestogens
Oral
Marketed
Methyltestosterone/ethisterone (Androgeston)
Injection
Marketed
Testosterone propionate/progesterone (Testoluton)
Veterinary
Marketed
Danazol/megestrol acetate (Dogalact)
Nandrolone decanoate/methandriol dipropionate (Filybol, Tribolin)
Nandrolone phenylpropionate/methandriol dipropionate (RWR)
Estrogens, progestogens, and androgens
Oral
Marketed
Methylestradiol/normethandrone (Ginecosid, Ginecoside, Mediol, Renodiol)
Not yet marketed
Ethinylestradiol/drospirenone/prasterone
Sublingual
Marketed
Estradiol/progesterone/methyltestosterone (Trihormonal)
Ethinylestradiol/ethisterone/methyltestosterone (Trinestryl, Trimone Sublets)
Injection
Marketed
Estradiol benzoate/progesterone/methandriol dipropionate (Progestandron)
Estradiol benzoate/progesterone/testosterone propionate (Lukestra, Steratrin, Trihormonal, Trinestryl)
Estradiol benzoate/estradiol valerate/norethisterone acetate/testosterone enanthate (Ablacton)
Estradiol dibutyrate/hydroxyprogesterone heptanoate/testosterone caproate (Triormon Depositum)
Estradiol diundecylate/hydroxyprogesterone heptanoate/testosterone cyclohexylpropionate (Trioestrine Retard)
Estradiol hexahydrobenzoate/hydroxyprogesterone caproate/testosterone hexahydrobenzoate (Trinestril AP)
Estrone/progesterone/testosterone (Tristeron, Tristerone)
Never marketed
Estrapronicate/hydroxyprogesterone heptanoate/nandrolone undecanoate (Trophobolene, Trophoboline)
Veterinary
Marketed
Estradiol/trenbolone acetate (Component, Compudose-G, Progro TE-H, Revalor, Synovex)
Estradiol benzoate/trenbolone acetate (Synovex Choice, Synovex One, Synovex Plus, Synovex with Trenbolone Acetate)
Miscellaneous
Oral
Marketed
Conjugated estrogens/bazedoxifene (Duavee)
Never marketed
Esterified estrogens/raloxifene
Estradiol/raloxifene
Transdermal
Marketed
Estradiol benzoate/prednisolone/salicylic acid (Alpicort E, Alpicort F, Alpicort Plus)
Vaginal
Marketed
Estradiol benzoate/gentamicin/hydrocortisone/nystatin (Cridermol Fem, Ginabiot, Ginecovan)
Estradiol benzoate/monalazone (Malun-25)
Mixed
Marketed
Goserelin/bicalutamide (ZolaCos CP)
Leuprorelin/norethisterone acetate (Lupaneta Pack)
See also
List of sex-hormonal medications available in the United States
List of sex-hormonal aqueous suspensions
List of steroid esters
List of marketed estradiol benzoate formulations
References
Anabolic–androgenic steroids
Sex-hormonal preparations
Drug-related lists
Estrogens
Progestogens | List of combined sex-hormonal preparations | [
"Chemistry"
] | 4,114 | [
"Drug-related lists"
] |
58,508,521 | https://en.wikipedia.org/wiki/International%20Overdose%20Awareness%20Day | International Overdose Awareness Day (IOAD or Overdose Day) is a global event held on 31 August each year since 2001. Its purpose is to raise awareness of overdoses, reduce the stigma of drug-related deaths and acknowledge the grief felt by families and friends. The first day, held in 2001 in Australia, saw 6,000 silver ribbons distributed across the country and into New Zealand. Since then the day has grown and is recognized in over 40 countries. So too, sadly, has the death toll from overdose continued to rise, particularly in North America.
The silver ribbon and the colour purple are representative symbols of the International Overdose Awareness Day. "Time to remember. Time to act" is the slogan used by campaigners.
History
The IOAD event was initiated in 2001 in Australia by S.J. Finn, then managing a needle and syringe program at the Salvation Army Crisis Centre in St Kilda, Victoria.
The coordination of events globally has been run by the Penington Institute since 2012.
Some events organized over time include:
2017: In Philadelphia, United States where 1,217 people died of opioid overdose that year (the highest death rate of any major U.S. city), there were calls for an overdose prevention site in 2018.
2018: Vigils were held in Vancouver, Canada where 38 people died of overdose in July 2018. Firefighters in the city attended 6,234 overdose calls in 2017. The Ontario Pharmacists Association issued warnings about the dangers of prescription opioids.
2018: The Alcoholism & Drug Abuse Council of Orange County, New York organised a candlelight vigil and remembrance ceremony at the Goshen Village Square. Guests were encouraged to bring a photo or other memento of a loved one.
2020: recovery arts organisations were planning live-stream public performances in four cities of the United Kingdom, replicating a successful initiative of 2019. However, they decided to create videos that would be broadcast on Facebook and YouTube due to the social distance measures of the COVID-19 Pandemic.
2021: Young Liberals of Norway (Unge Venstre) marked the day with placing 260 crosses in front of the Storting. The 260 crosses represented the average 260 people who die of drug-related overdoses in Norway each year, which the political party means is a consequence of the Norwegian government's war on drugs.
2022: networks of drug users in Barcelona, Spain organized a walk the city center, pasting silhouettes of neighbours victims of overdose during the current year in remembrance.
The event is organized simultaneously worldwide, with Penington Institute facilitating communication materials and awareness campaigns. International Overdose Awareness Day badges and wristbands depicting the silver ribbon are produced and distributed to local groups globally.
See also
International Drug Users Remembrance Day
Drug overdose
Harm reduction
Penington Institute
INPUD
Substance abuse prevention
References
External links
(Official website)
Addiction medicine
August observances
Drug culture
Drug overdose
Drug policy
Drug-related deaths
Drug safety
Health awareness days
Harm reduction
Public health
Public health organizations
Substance intoxication
Substance abuse | International Overdose Awareness Day | [
"Chemistry"
] | 615 | [
"Drug safety"
] |
58,508,562 | https://en.wikipedia.org/wiki/Levonorgestrel%20cyclobutylcarboxylate | Levonorgestrel cyclobutylcarboxylate (or levonorgestrel 17β-cyclobutylcarboxylate; developmental code name HRP-001) is a progestin and a progestogen ester which was studied for potential use as an injectable hormonal contraceptive but was never marketed. It was developed by the World Health Organization's Special Programme on Human Reproduction in the 1980s. Analogues of levonorgestrel cyclobutylcarboxylate include levonorgestrel butanoate (HRP-002) and levonorgestrel cyclopropylcarboxylate (HRP-003).
See also
List of progestogen esters § Esters of 19-nortestosterone derivatives
Progestogen-only injectable contraceptive
References
Abandoned drugs
Ethynyl compounds
Anabolic–androgenic steroids
Carboxylic acids
Estranes
Enones
Sex hormone esters and conjugates
Progestogens
Progestogen esters
World Health Organization | Levonorgestrel cyclobutylcarboxylate | [
"Chemistry"
] | 228 | [
"Carboxylic acids",
"Drug safety",
"Functional groups",
"Abandoned drugs"
] |
58,508,563 | https://en.wikipedia.org/wiki/Levonorgestrel%20cyclopropylcarboxylate | Levonorgestrel cyclopropylcarboxylate (developmental code name HRP-003), or levonorgestrel 17β-cyclopropylcarboxylate, is a progestin and a progestogen ester which was studied for potential use as an injectable hormonal contraceptive but was never marketed. It was developed by the World Health Organization's Special Programme on Human Reproduction in the 1980s. Analogues of levonorgestrel cyclopropylcarboxylate include levonorgestrel cyclobutylcarboxylate (HRP-001) and levonorgestrel butanoate (HRP-002).
See also
List of progestogen esters § Esters of 19-nortestosterone derivatives
Progestogen-only injectable contraceptive
References
Abandoned drugs
Ethynyl compounds
Anabolic–androgenic steroids
Carboxylic acids
Estranes
Enones
Sex hormone esters and conjugates
Progestogens
Progestogen esters
World Health Organization | Levonorgestrel cyclopropylcarboxylate | [
"Chemistry"
] | 229 | [
"Carboxylic acids",
"Drug safety",
"Functional groups",
"Abandoned drugs"
] |
58,510,824 | https://en.wikipedia.org/wiki/C17H18N2O2 | {{DISPLAYTITLE:C17H18N2O2}}
The molecular formula C17H18N2O2 (molar mass: 282.337 g/mol) may refer to:
Lysergic acid methyl ester
Salpn ligand
Molecular formulas | C17H18N2O2 | [
"Physics",
"Chemistry"
] | 60 | [
"Molecules",
"Set index articles on molecular formulas",
"Isomerism",
"Molecular formulas",
"Matter"
] |
58,511,113 | https://en.wikipedia.org/wiki/Phialophora%20fastigiata | Phialophora fastigiata is a mitosporic, saprophytic fungus commonly found in soil, and on wood, and wood-pulp. This species was initially placed in the genus Cadophora but was later transferred to the genus Phialophora based on morphological and growth characteristics. In culture, P. fastigiata produces olive-brown, velvety colonies. The fungus is recognizable microscopically due to the presence of distinctive, funnel-shaped cuffs (collarettes) encircling the tips of phialides that bear slimy conidia. The fungus is often implicated in soft-rot wood decay due to its ability to degrade lignin, cellulose and pectin. It has also been reported to cause blue staining of wood and wood pulp.
History and taxonomy
Phialophora fastigiata was originally described in 1928 as Cadophora fastigiata by Lagerberg and Melin, who erected the genus Cadophora to accommodate C. fastigiata. In 1937, Conant compared eight species of Cadophora with Phialophora verrucosa and determined that they belonged to the same genus. As such, seven species of Cadophora, including C. fastigiata were transferred to the genus Phialophora. Although later examination of the internal transcribed spacers of ribosomal DNA (rDNA) genes in Cadophora melinii and P. fastigiata showed morphological similarity, the colony morphology of the two species is distinctive.
Growth and morphology
Macroscopically, P. fastigiata colonies reach in diameter after being grown at 20 °C on malt extract agar for 10 days. They exhibit an olive-brown or reddish-brown velvety appearance, and grow with a border of hyaline (glassy) mycelium. Aerial mycelium form a floccose (fluffy) greyish-brown turf 1.0-6.5mm high, and produce rope-like strands towards the centre of the colony. Although isolates usually grow uniformly, slight differences in colour, numbers of conidiophores and numbers of aerial mycelium have been observed.
Phialophora fastigiata are microscopically recognized by the production of light brown, flask-shaped phialides that are produced laterally on hyphae and produce funnel-shaped collarettes. In Petri dish cultures, the fungus tends to develop hyphal strands that are 3-4μm in diameter and show cell-wall thickening with age. Slimy conidia are produced in clumps at the apex of phialides, and are oval shaped (ovoid) to button shaped (ellipsoidal) with a pinched base. The conidia initially exhibit a hyaline (unpigmented) appearance, but turn light brown with age.
Physiology
Isolates of P. fastigiata are able to grow at temperatures ranging from 3 °C to 35 °C, with an optimum temperature range of 20 °C–25 °C and pH range between 4–9. Extracts of water and acetone from balsam fir, black spruce, white spruce and red spruce have been shown to stimulate the growth of the fungus in culture. The presence of biotin also increases the growth of this fungus and extracts of ammonium tartrate increase mycelium production. This saprophytic fungus is able to gain energy from decaying organic matter, and is able to utilize asparagine and potassium nitrate as sources of nitrogen, as well as L-arabinose as a source of carbon.
Phialophora fastigiata is able to produce a variety of degradation enzymes, including pectinase, amylase, xylanase, cellulase and mannanase, which allow it to cause wood decay and post-harvest rot. Although there has been no investigation into the management of P. fastigiata, the fungus is known to be susceptible to the antimicrobial activity of ethanolic extract from Halacsya sendtneri, a flowering plant in the family Boraginaceae. The fungus is also susceptible to antimycins produced by Streptomyces species. Conversely, P. fastigiata exhibits antimicrobial activity against Gaeumannomyces graminis var tritici, a plant pathogen that causes take-all disease in wheat.
Habitat and ecology
Phialophora fastigiata is commonly isolated from soil and wood. The earliest reports of the fungus came from countries and regions rich in wood, such as Sweden, Norway and Canada. It was later isolated from a spruce plantation in Norway and has been found to grow on wood pulp in Sweden. It is also the most abundant species found in slime from paper mills in New Brunswick and Newfoundland, and has been isolated from wheat-field soils in Western Australia.
The fungus is psychrotolerant (able to grow at low temperatures), and has been isolated from soil, straw and wood in the Ross Sea region of Antarctica. It has also been isolated from the water-saturated wood of Betula pendula trees, dialysis water, municipal drinking water, groundwater, surface water, and tap water.
Commercial implications
Phialophora fastigiata is a soft rot fungus that has been found to widen cavities in birch and Scots pine sapwood by increasing growth at the hyphal tip and secreting lignolytic enzymes (involved in the degradation of lignin) from the hyphal surface. The fungus can also cause cavities in wood and plants via an erosion-type attack. The ability of the fungus to degrade the wood of Populus tremuloides (trembling aspen) has been noted to limit the sale of aspen, which represents 54% of commercial timber.
P. fastigiata also commonly causes blue staining of wood. It has been found to grow on wood pulp with a greyish-green tinge, causing the wood pulp to appear blue and is one of the most common species of fungi associated with discolored xylem in the stems of B. pendula. Degradation and discoloration of wood by P. fastigiata affect the production quality of pulp and paper.
References
Eurotiomycetes
Fungi described in 1937
Fungus species | Phialophora fastigiata | [
"Biology"
] | 1,305 | [
"Fungi",
"Fungus species"
] |
58,513,265 | https://en.wikipedia.org/wiki/Silica%20cycle | The silica cycle is the biogeochemical cycle in which biogenic silica is transported between the Earth's systems. Silicon is considered a bioessential element and is one of the most abundant elements on Earth. The silica cycle has significant overlap with the carbon cycle (see carbonate–silicate cycle) and plays an important role in the sequestration of carbon through continental weathering, biogenic export and burial as oozes on geologic timescales.
Overview
Silicon is the eighth most abundant element in the universe and the second most abundant element in the Earth's crust (the most abundant is oxygen). The weathering of the Earth's crust by rainwater rich in carbon dioxide is a key process in the control of atmospheric carbon dioxide. It results in the generation of silicic acid in aqueous environments. Silicic acid, Si(OH)4, is a hydrated form of silica found only as an unstable solution in water, yet it plays a central role in the silica cycle.
Silicifiers are organisms that use silicic acid to precipitate biogenic silica, SiO2. Biogenic silica, also referred to as opal, is precipitated by silicifiers as internal structures and/or external structures. Silicifiers are among the most important aquatic organisms. They include micro-organisms such as diatoms, rhizarians, silicoflagellates and several species of choanoflagellates, as well as macro-organisms such as siliceous sponges. Phototrophic silicifiers, such as diatoms, globally consume vast amounts of silicon along with nitrogen (N), phosphorus (P), and inorganic carbon (C), connecting the biogeochemistry of these elements and contributing to the sequestration of atmospheric carbon dioxide in the ocean. Heterotrophic organisms like rhizarians, choanoflagellates, and sponges produce biogenic silica independently of the photoautotrophic processing of C and N.
The diatoms dominate the fixation and export of particulate matter in the contemporary marine silica cycle. This includes the export of organic carbon from the euphotic zone to the deep ocean via the biological carbon pump. As a result, diatoms, and other silica-secreting organisms play crucial roles in the global carbon cycle by sequestering carbon in the ocean. The connection between biogenic silica and organic carbon, together with the significantly higher preservation potential of biogenic siliceous compounds compared to organic carbon makes opal accumulation records of interest in paleoceanography and paleoclimatology.
Understanding the silica cycle is important for understanding the functioning of marine food webs, biogeochemical cycles, and the biological pump. Silicic acid is delivered to the ocean through six pathways as illustrated in the diagram above, which all ultimately derive from the weathering of the Earth's crust.
Terrestrial silica cycling
Silica is an important nutrient utilized by plants, trees, and grasses in the terrestrial biosphere. Silicate is transported by rivers and can be deposited in soils in the form of various siliceous polymorphs. Plants can readily uptake silicate in the form of H4SiO4 for the formation of phytoliths. Phytoliths are tiny rigid structures found within plant cells that aid in the structural integrity of the plant. Phytoliths also serve to protect the plants from consumption by herbivores who are unable to consume and digest silica-rich plants efficiently. Silica release from phytolith degradation or dissolution is estimated to occur at a rate double that of global silicate mineral weathering. Considering biogeochemical cycling within ecosystems, the import and export of silica to and from terrestrial ecosystems is small.
Weathering
Silicate minerals are abundant in rock formations all over the planet, comprising approximately 90% of the Earth's crust. The primary source of silicate to the terrestrial biosphere is weathering. The process and rate of weathering is variable, depending on rainfall, runoff, vegetation, lithology, and topography.
Given sufficient time, rainwater can dissolve even a highly resistant silicate-based mineral such as quartz. Water breaks the bonds between atoms in the crystal:
The overall reaction for the dissolution of quartz results in silicic acid
Another example of a silicate-based mineral is enstatite (MgSiO3). Rainwater weathers this to silicic acid as follows:
MgSiO3(s) + 2CO2(g) + H2O(l) = Mg2+(aq) + 2HCO3- (aq) + SiO2(aq)
Reverse weathering
In recent years, the effect of reverse weathering on biogenic silica has been of interest in quantifying the silica cycle. During weathering, dissolved silica is delivered to oceans through glacial runoff and riverine inputs. This dissolved silica is taken up by a multitude of marine organisms, such as diatoms, and is used to create protective shells. When these organisms die, they sink through the water column. Without active production of biogenic SiO2, the mineral begins diagenesis. Conversion of this dissolved silica into authigenic silicate clays through the process of reverse weathering constitutes a removal of 20-25% of silicon input.
Reverse weathering is often found in river deltas as these systems have high sediment accumulation rates and are observed to undergo rapid diagenesis. The formation of silicate clays removes reactive silica from the pore waters of sediment, increasing the concentration of silica found in the rocks that form in these locations.
Silicate weathering also appears to be a dominant process in deeper methanogenic sediments, whereas reverse weathering is more common in surface sediments, but still occurs at a lower rate.
Sinks
The major sink of the terrestrial silica cycle is export to the ocean by rivers. Silica that is stored in plant matter or dissolved can be exported to the ocean by rivers. The rate of this transport is approximately 6 Tmol Si yr−1. This is the major sink of the terrestrial silica cycle, as well as the largest source of the marine silica cycle. A minor sink for terrestrial silica is silicate that is deposited in terrestrial sediments and eventually exported to the Earth's crust.
Marine inputs
Riverine
As of 2021, the best estimate of the total riverine input of silicic acid is 6.2 (±1.8) Tmol Si yr−1. This is based on data representing 60% of the world river discharge and a discharge-weighted average silicic acid riverine concentration of 158 μM−Si. However, silicic acid is not the only way silicon can be transferred from terrestrial to riverine systems, since particulate silicon can also be mobilised in crystallised or amorphous forms. According to Saccone and others in 2007, the term "amorphous silica" includes biogenic silica (from phytoliths, freshwater diatoms, sponge spicules), altered biogenic silica, and pedogenic silicates, the three of which can have similar high solubilities and reactivities. Delivery of amorphous silica to the fluvial system has been reviewed by Frings and others in 2016, who suggested a value of 1.9(±1.0) Tmol Si yr−1. Therefore, the total riverine input is 8.1(±2.0) Tmol Si yr−1.
Aeolian
No progress has been made regarding aeolian dust deposition into the ocean and subsequent release of silicic acid via dust dissolution in seawater since 2013, when Tréguer and De La Rocha summed the flux of particulate dissolvable silica and wet deposition of silicic acid through precipitation. Thus, the best estimate for the aeolian flux of silicic acid, FA, remains 0.5(±0.5) Tmol Si yr−1.
Sandy beaches
A 2019 study has proposed that, in the surf zone of beaches, wave action disturbed abiotic sand grains and dissolved them over time. To test this, the researchers placed sand samples in closed containers with different kinds of water and rotated the containers to simulate wave action. They discovered that the higher the rock/water ratio within the container, and the faster the container spun, the more silica dissolved into solution. After analyzing and upscaling their results, they estimated that anywhere from 3.2 ± 1.0 – 5.0 ± 2.0 Tmol Si yr−1 of lithogenic DSi could enter the ocean from sandy beaches, a massive increase from a previous estimate of 0.3 Tmol Si yr−1. If confirmed, this represents a significant input of dissolved LSi that was previously ignored.
Marine silica cycling
Siliceous organisms in the ocean, such as diatoms and radiolaria, are the primary sink of dissolved silicic acid into opal silica. Only 3% of the Si molecules dissolved in the ocean are exported and permanently deposited in marine sediments on the seafloor each year, demonstrating that silicon recycling is a dominant process in the oceans. This rapid recycling is dependent on the dissolution of silica in organic matter in the water column, followed by biological uptake in the photic zone. The estimated residence time of the silica biological reservoir is about 400 years. Opal silica is predominately undersaturated in the world's oceans. This undersaturation promotes rapid dissolution as a result of constant recycling and long residence times. The estimated turnover time of Si is 1.5x104 years. The total net inputs and outputs of silica in the ocean are 9.4 ± 4.7 Tmol Si yr−1 and 9.9 ± 7.3 Tmol Si yr−1, respectively.
Biogenic silica production in the photic zone is estimated to be 240 ± 40 Tmol Si year −1. Dissolution in the surface removes roughly 135 Tmol Si year−1, while the remaining Si is exported to the deep ocean within sinking particles. In the deep ocean, another 26.2 Tmol Si Year−1 is dissolved before being deposited to the sediments as opal rain. Over 90% of the silica here is dissolved, recycled and eventually upwelled for use again in the euphotic zone.
Sources
The major sources of marine silica include rivers, groundwater flux, seafloor weathering inputs, hydrothermal vents, and atmospheric deposition (aeolian flux). Rivers are by far the largest source of silica to the marine environment, accounting for up to 90% of all the silica delivered to the ocean. A source of silica to the marine biological silica cycle is silica that has been recycled by upwelling from the deep ocean and seafloor.
The diagram on low-temperature processes shows how these can control the dissolution of (either amorphous or crystallized) siliceous minerals in seawater in and to the coastal zone and in the deep ocean, feeding submarine groundwater (FGW) and dissolved silicon in seawater and sediments (FW). These processes correspond to both low and medium energy flux dissipated per volume of a given siliceous particle in the coastal zone, in the continental margins, and in the abysses and to high-energy flux dissipated in the surf zone.
Sinks
Rapid dissolution in the surface removes roughly 135 Tmol opal Si year−1, converting it back to soluble silicic acid that can be used again for biomineralization. The remaining opal silica is exported to the deep ocean in sinking particles. In the deep ocean, another 26.2 Tmol Si Year−1 is dissolved before being deposited to the sediments as opal silica. At the sediment water interface, over 90% of the silica is recycled and upwelled for use again in the photic zone. Biogenic silica production in the photic zone is estimated to be 240 ± 40 Tmol si year −1. The residence time on a biological timescale is estimated to be about 400 years, with each molecule of silica recycled 25 times before sediment burial.
Deep seafloor deposition is the largest long-term sink of the marine silica cycle (6.3 ± 3.6 Tmol Si year−1), and is roughly balanced by the sources of silica to the ocean. The silica deposited in the deep ocean is primarily in the form of siliceous ooze. When opal silica accumulates faster than it dissolves, it is buried and can provide a diagenetic environment for marine chert formation. The processes leading to chert formation have been observed in the Southern Ocean, where siliceous ooze accumulation is the fastest. Chert formation however can take tens of millions of years. Skeleton fragments from siliceous organisms are subject to recrystallization and cementation. Chert is the main fate of buried siliceous ooze and permanently removes silica from the oceanic silica cycle.
The siliceous ooze is eventually subducted under the crust and metamorphosed in the upper mantle. Under the mantle, silicate minerals are formed in oozes and eventually uplifted to the surface. At the surface, silica can enter the cycle again through weathering. This process can take tens of millions of years. The only other major sink of silica in the ocean is burial along continental margins (3.6 ± 3.7 Tmol Si year −1), primarily in the form of siliceous sponges. Due to the high degrees of uncertainty in source and sink estimations, it's difficult to conclude if the marine silica cycle is in equilibrium. The residence time of silica in the oceans is estimated to be about 10,000 years. Silica can also be removed from the cycle by becoming chert and being permanently buried.
Anthropogenic influences
The rise in agriculture of the past 400 years has increased the exposure rocks and soils, which has resulted in increased rates of silicate weathering. In turn, the leaching of amorphous silica stocks from soils has also increased, delivering higher concentrations of dissolved silica in rivers. Conversely, increased damming has led to a reduction in silica supply to the ocean due to uptake by freshwater diatoms behind dams. The dominance of non-siliceous phytoplankton due to anthropogenic nitrogen and phosphorus loading and enhanced silica dissolution in warmer waters has the potential to limit silicon ocean sediment export in the future.
In 2019 a group of scientists suggested acidification is reducing diatom silica production in the Southern Ocean.
Role in climate regulation
The silica cycle plays an important role in long term global climate regulation. The global silica cycle also has large effects on the global carbon cycle through the carbonate-silicate cycle. The process of silicate mineral weathering transfers atmospheric CO2 to the hydrologic cycle through the chemical reaction displayed above. Over geologic timescales, the rates of weathering change due to tectonic activity. During a time of high uplift rate, silicate weathering increases which results in high CO2 uptake rates, offsetting increased volcanic CO2 emissions associated with the geologic activity. This balance of weathering and volcanoes is part of what controls the greenhouse effect and ocean pH over geologic time scales.
Biogenic silica accumulation on the sea floor contains lot of information about where in the ocean export production has occurred on time scales ranging from hundreds to millions of years. For this reason, opal deposition records provide valuable information regarding large-scale oceanographic reorganizations in the geological past, as well as paleoproductivity. The mean oceanic residence time for silicate is approximately 10,000–15,000 yr. This relative short residence time, makes oceanic silicate concentrations and fluxes sensitive to glacial/interglacial perturbations, and thus an excellent proxy for evaluating climate changes.
Isotope ratios of oxygen (O18:O16) and silicon (Si30:Si28) are analysed from biogenic silica preserved in lake and marine sediments to derive records of past climate change and nutrient cycling (De La Rocha, 2006; Leng and Barker, 2006). This is a particularly valuable approach considering the role of diatoms in global carbon cycling. In addition, isotope analyses from BSi are useful for tracing past climate changes in regions such as in the Southern Ocean, where few biogenic carbonates are preserved.
The silicon isotope compositions in fossil sponge spicules (δ30Si) are being increasingly often used to estimate the level of silicic acid in marine settings throughout the geological history, which enables the reconstruction of past silica cycles.
See also
Carbon cycle
Lithogenic silica
Oxygen cycle
Silicification
Silicon isotope biogeochemistry
References
Biogeochemical cycle
Silicon | Silica cycle | [
"Chemistry"
] | 3,564 | [
"Biogeochemical cycle",
"Biogeochemistry"
] |
58,513,865 | https://en.wikipedia.org/wiki/List%20of%20tallest%20minarets | This is a list of the tallest minarets in the world. It ranks minarets by their height.
The tallest minaret in the world is the minaret of the Djamaa el Djazaïr in Algiers, Algeria which stands at 265 metres (870 ft).
List of tallest minarets
This list ranks the tallest minarets in the world. Only minarets taller than 25 metres (82 feet) or remarkable for some distinctive feature are included.
See also
List of tallest mosques
Minaret
Mosque
List of oldest minarets
References
Minarets | List of tallest minarets | [
"Engineering"
] | 117 | [
"Structural engineering",
"Towers"
] |
58,514,123 | https://en.wikipedia.org/wiki/Claudine%20Stirling | Claudine Helen Stirling is a New Zealand isotope geochemistry academic. As of 2018, she is a full professor at the University of Otago. In 2024 she was elected as a Fellow of the Royal Society Te Apārangi.
Academic career
After a 1996 PhD titled 'High-precision U-series dating of corals from Western Australia : implication for last interglacial sea-levels' at the Australian National University, Stirling worked at University of Michigan and ETH Zürich before moving to the University of Otago in 2006, rising to full professor in 2018. Prof Stirling is a member of the Department of Geology with current research interests including: isotope geochemistry, biogeochemical cycles of trace metals, paleoceanography & paleoclimatology, and environmental geochemistry.
In 2024 Stirling was elected as a Fellow of the Royal Society Te Apārangi.
Selected works
Halliday, Alex N., Der-Chuen Lee, John N. Christensen, Mark Rehkämper, Wen Yi, Xiaozhong Luo, Chris M. Hall, Chris J. Ballentine, Thomas Pettke, and Claudine Stirling. "Applications of multiple collector-ICPMS to cosmochemistry, geochemistry, and paleoceanography." Geochimica et Cosmochimica Acta 62, no. 6 (1998): 919–940.
Amelin, Yuri, Angela Kaltenbach, Tsuyoshi Iizuka, Claudine H. Stirling, Trevor R. Ireland, Michail Petaev, and Stein B. Jacobsen. "U–Pb chronology of the Solar System's oldest solids with variable 238U/235U." Earth and Planetary Science Letters 300, no. 3-4 (2010): 343–350.
Stirling, Claudine H., Morten B. Andersen, Emma-Kate Potter, and Alex N. Halliday. "Low-temperature isotopic fractionation of uranium." Earth and Planetary Science Letters 264, no. 1-2 (2007): 208–225.
Gutjahr, Marcus, Martin Frank, Claudine H. Stirling, Veronika Klemm, Tina Van de Flierdt, and Alex N. Halliday. "Reliable extraction of a deepwater trace metal isotope signal from Fe–Mn oxyhydroxide coatings of marine sediments." Chemical Geology 242, no. 3-4 (2007): 351–370.
Rehkämper, Mark, Maria Schönbächler, and Claudine H. Stirling. "Multiple collector ICP‐MS: Introduction to instrumentation, measurement techniques and analytical capabilities." Geostandards Newsletter 25, no. 1 (2001): 23–40.
References
Living people
New Zealand women academics
Australian National University alumni
Academic staff of the University of Otago
University of Michigan faculty
Academic staff of ETH Zurich
Geochemists
New Zealand chemists
New Zealand women chemists
Year of birth missing (living people)
Fellows of the Royal Society of New Zealand | Claudine Stirling | [
"Chemistry"
] | 634 | [
"Geochemists"
] |
58,514,752 | https://en.wikipedia.org/wiki/Archean%20felsic%20volcanic%20rocks | Archean felsic volcanic rocks are felsic volcanic rocks that were formed in the Archean Eon (4 to 2.5 billion years ago). The term "felsic" means that the rocks have silica content of 62–78%. Given that the Earth formed at ~4.5 billion year ago, Archean felsic volcanic rocks provide clues on the Earth's first volcanic activities on the Earth's surface started 500 million years after the Earth's formation.
As the Archean Earth was hotter than the present, formation of felsic volcanic rocks may differ from the modern plate tectonics.
Archean felsic volcanic rocks are distributed only in the preserved Archean greenstone belts, where deformed sequences of volcanic-sedimentary rocks are common. Felsic volcanic rocks are rare in the early Earth and only contribute to less 20% of rocks in the Archean greenstone belts worldwide. In contrast, mafic volcanic rocks (such as basalt and komatiite, silicate content <52%) occupy about 50% in the greenstone belts. Thus, felsic volcanic rocks are rare members in the Archean terranes.
Archean felsic volcanic activities commonly occur in submarine environments. The composition of Archean felsic volcanic rocks are equivalent to a spectrum between dacite and rhyolite. They can be distinguished by their mineral assemblages, rock chemistry and rock layer relationship in the sequences.
Archean felsic volcanic rocks are utilised to date the timing of geological events and match distant rock units in separated Archean cratons. They are important to reconstruct Archean geological environments.
Felsic granitoids are the most prevalent rock type in Archean terranes. These intrusive felsic igneous rocks include TTG suites (Tonalite-trondhjemite-granodiorite) that contributes over half the portion of Archean cratons. They have implications in finding how the felsic volcanic rocks were formed and related to the granitoids.
Occurrence
Archean felsic volcanic rocks are only preserved in Archean cratons. A craton is an ancient stable continental block. Also, a craton has survived from plate tectonics that pull apart, collide or tear continents. On average, the felsic volcanic rocks only contribute to ≈15-20% in volcanic rocks of greenstone belts. See Figure 2 and Table 1 for Examples of Archean felsic volcanic rocks occurrence.
All Archean felsic volcanic rocks are distributed in greenstone belts. In Archean cratons, greenstone belts represent supracrustal rocks formed at the Earth's surface and the belts are dominated by volcano-sedimentary sequences. Some volcanic sequences can be several kilometers thick, such as the Warrawoona Group of Eastern Pilbara Craton. However, ultramafic and mafic units make up the major volume of the volcanic units. The remaining volcanic units are extensive but thin felsic volcanic layers, such as Duffer Formation of the Warrawoona Group. The greenstone belts may be subsequently intruded by dome-shaped magma chambers. The intrusion deformed the felsic volcanic rocks along with the volcano-sedimentary sequences.
Observing modern volcanic processes is relatively easier than observing Archean volcanism, because erosion constantly started removing earlier formed materials. So, studying the Archean supracrustal rocks back in deep time may be subjected to sampling bias.
Characteristics
Mineralogy and texture
The meaning of "felsic" refers to high silica (SiO2) content from 62 to 78 wt% in rock. In terms of mineralogy, the felsic volcanic rocks are rich in feldspar and quartz. A typical mineral assemblage is quartz + feldspar (albite/oligoclase) + amphibole (chlorite) + micas (biotite and/or muscovite). The mineralogy seems similar with modern rhyolites and dacites. The volcanics are aphanitic, whereas some exhibits porphyritic texture that certain larger minerals (phenocrysts) are visible by eyes.
Felsic volcanic rocks also include felsic tuff that was formed when tephra was consolidated. Tuff is composed of volcanic ash, glass shards and lithic fragments. Reported eutaxitic tuff from Superior Province, Canada (Figure 3), contains lenticular fiamme. When hot pumice deposits on a cool surface, it is rapidly cooled, recrystallised and welded into quartz with flame-like ending tips. The eutaxitic texture represents a hot vapour-phase emplacement of the fragmented volcanic materials on the Earth's surface.
Flow bands are present in massive, uniform felsic lava flow units. When the viscous lava flow encounters a surface, friction drags the mobile lava and forms internal banding.
Structureless hyaloclastite is commonly found in Archean felsic volcanic rocks. In submarine environments, water quenches and cools lava rapidly during volcanic eruption. The flow is fragmented and form glassy volcanic breccia.
Geochemistry
The composition of Archean felsic volcanic rocks falls in the calc-alkaline series. Such magmatic series indicate that fractional crystallisation of magma occurred during cooling. Magnesium and iron content in the rock are low, and it forms dacite or rhyolite. Magma is a mixture of various minerals. When minerals crystallise from the molten magma, they are progressively removed and dissociated from the melt. The last proportion of the melt is strongly fractionated, causing richness in quartz and feldspars that make the volcanic rocks felsic.
Dacite and rhyolite are characterised by high silica (SiO2) content from 62 to 78 wt%. The average composition of felsic volcanic rocks in Archean greenstone belts is between dacite and rhyolite (Table 2). In comparison, the modern felsic volcanic rock average composition (after Archean, <2.5 Ga) is similar to rhyolite, indicating a more felsic shift with greater alkali content in felsic volcanism. However, the composition may be biased because of weathering right after deposition or metamorphism during later stages of deformation.
Archean felsic volcanic rocks also have high zircon abundance. Incompatible elements, like zirconium, are reluctant to substitute into early-forming crystals. As a result, they tend to remain in the melt. In strongly fractionated felsic magma, zircon is easily saturated. As a result, zircon is common in felsic rocks. The timing of felsic volcanism and tectonic constraints can be identified by radiometric dating and isotopic analysis.
Eruption style
In the Archean aeon, underwater eruptions of felsic lava were common. Submarine eruption is evident by coarse volcanic breccia formed in situ, hyaloclastite or underwater pyroclastic deposits (clastic rock, composed of tephra only). Since felsic magma is viscous, volcanic eruptions that form dacite or rhyolite are explosive and violent. The Archean felsic eruption may be assigned to Vesuvius eruption type in the present day.
Submarine rhyolitic flows were widespread in the Archean but are uncommon in the modern volcanic environment. Viscous felsic eruption often causes pyroclastic flow (hot, dense gas with volcanic fragments) instead of fluid lava flow. However, if the rhyolitic lava is still molten during eruption, it can behave and flow like fluid lava.
Subaqueous deposits
Felsic lava flow and lava dome are the two common types of underwater deposits formed by Archean felsic volcanic rocks (Fig. 4). Documented Archean lava structures are distinctive from post-Archean felsic lava because underwater eruptions are so rare in the post-Archean. The dacitic or rhyolitic lava flows are quenched right after the eruption. When seawater contacts the flow, the lava quickly cools down. Finally, The lava solidifies and breaks up as clasts, and the clasts accumulate on the flow fronts to form breccia.
Lava flow
Effusive felsic lava flows elongate several kilometres. During an eruption, lava continuously wells out from the vent, then starts to flow outward on the sea floor. Due to quenching, lava is rapidly fragmented to form breccia. A new lobe of lava is injected inside the breccia but it is cooled less quickly, and pushes the flow further outwards.
Lava dome
Short, stocky dome with subsequent pyroclastic deposits extend less than few kilometres long. When explosive eruption occurs, volcanic fragments would be deposited by violent pyroclastic flows. Coarse breccia would be formed as a result. Submarine sediments would subsequently be deposited along the steep flank of the volcano. Submarine landslides would occur to form turbidites.
Stratigraphic significance
Archean felsic volcanic rocks are important in determining absolute age of the rock units in greenstone belts. Felsic eruptions are episodic, making the felsic volcanic layers distinctive stratigraphic units. Also, felsic volcanic rocks are distributed across long distances because of their extensive deposition. However, the rock sequences of greenstone belts are commonly obscured by later deformation, such as regional folding or intrusion of granitoids. By identifying these felsic sequences and dating their time of formation, stratigraphic units of different locations can be correlated despite the obstacles or discontinuity between felsic volcanic units.
Timing of volcanism
The geochronology of Archean events strongly relies on U-Pb dating and Lu-Hf dating. Since mafic rocks (contain low silica content, such as basalt) are lack of zircon, only the age of felsic rocks can be dated among the volcanic rocks in greenstone belts. As felsic volcanic rocks are episodically deposited in between mafic layers, the age range of a particular mafic layer can be constrained by the upper and lower felsic volcanic layers. Thus the time of occurrence and the duration of volcanic episodes can be revealed.
Relationships between Archean felsic volcanic rocks and granitoids
From TTG to GMS granitoids
Two plutonic, igneous rock suites form 50% of Archean cratons. They are (1) Tonalite-trondhjemite-granodiorite (TTG) suites and (2) Granite-Monzonite-Syenite (GMS) suites in chronological order. They are magma chambers that later formed the volcanics on the Earth's surface by volcanic eruption. Later they intruded the supracrustal rocks of similar age and composition in the Archean. The uprising magma bodies deformed the surface greenstone belt on a cratonic scale.
The two kinds of granitoids have different magma origins: (a) melting of water-rich mafic materials formed older sodium-rich TTG and (b) melting of felsic materials (e.g. TTG and/or sediments) formed younger potassium-rich GMS (see Table 3). They imply gradual chemical changes in the magma and the Earth's crust.
Conflicting compositions
Records of Archean felsic volcanic rocks shows a peculiar trend. The eruption of felsic volcanic rocks and plutonic activities in Archean are largely synchronised as show in overlapping zircon ages. On contrary, the chemical compositions of some felsic volcanic rocks are similar to that of GMS but they are much older than GMS. For example, a GMS-like rhyolite unit in the Abitibi Greenstone Belt (abnormally more enriched in potassium and heavy rare-earth elements than other Archean felsic volcanic rocks) has no plutonic equivalent in the same period. The composition of felsic volcanic rocks are being altered concurrently with shifting granitoid composition.
Possible relationships
The older GMS-like felsic volcanic rocks formed with similar age of TTG has two implications:
GMS may have intruded the crust and GMS-like volcanics at a very shallow depth. Later, intense erosion rips up all GMS suites and deposited at a proximal distance. If this is true, then GMS and TTG intruded the crust together at the same time. No solid evidence is present yet but the irregular geochemical fingerprints may link both to TTG or GMS.
GMS is concentrated at the upper crust and TTG at deeper intermediate crust. Later, GMS as well as GMS-like volcanics are eroded and deposit as sediments. The detrital zircons may show a range of mixed GMS and TTG geochemical signature.
Limitation
Revealing the relationship between Archean felsic volcanic rocks and the granitoids may be difficult. It is because weathering alters the geochemical signatures of the felsic rocks above the Earth's surface. The earliest weathering record can be traced back to 3.8 Ga during Eoarchean. Potassium is enriched but sodium is depleted in these weathered felsic rocks. Altered feldspars in the rocks may result in such anomalous signatures.
See also
Eoarchean geology
Tectonic evolution of the Barberton greenstone belt
References
Archean volcanism
Felsic rocks | Archean felsic volcanic rocks | [
"Chemistry"
] | 2,841 | [
"Felsic rocks",
"Igneous rocks by composition"
] |
58,514,780 | https://en.wikipedia.org/wiki/Harry%20Nursten | Harry Erwin Nursten (August 1927 – 20 December 2011) was a British food chemist, specialising in flavour chemistry at the Department of Nutrition and Food Sciences at the University of Reading.
Biography
Harry Erwin Nursten was born in Czechoslovakia in August 1927, son of Sergius Nursten and Helene. The family managed to escape to England shortly before the Second World War. In the 1939 England and Wales Register the parents (“Nursem”) were living at Corringham Court, Golders Green; Sergius was listed as “Dental surgeon (seeking work).” The family settled in Ilkley, Yorkshire, where Harry attended Ilkley Grammar School and gained his Higher School Certificate in 1944. He went to the University of Leeds where he read colour chemistry and dyeing, followed by a PhD in colour chemistry, awarded in 1949.
In the summer of that year Nursten was one of a group of volunteers harvesting at Windlestone Hall. Also there was Jean Frobisher, Harry's fellow student and bridge partner at Ilkley Grammar School, and now a welfare worker. They were married on 23 December 1950 at St Paul's Church, Esholt.
After more research at Leeds, Nursten taught dyeing and textile chemistry at Nottingham Technical College. He returned to Leeds in 1955 as a lecturer in the Procter Department of Leather Science.
Following two sabbaticals at the Massachusetts Institute of Technology and UC Davis, he moved into the area of food and flavour science. In 1976, he was appointed Chair of Food Science at the University of Reading. Following the merger of the National College of Food Technology and the Department of Food Science, he became Head of Department of one of the biggest Food Science Departments in the UK. In 1992, the year he retired, Nursten ensured that the Hugh Macdonald Sinclair endowment was used to set up a new centre for human nutrition research at the University of Reading.
Harry Nursten died in Reading on 20 December 2011. His wife, Jean Patricia Nursten, is a noted Professor of social work, and author.
Some publications
References
British chemists
People educated at Ilkley Grammar School
Academics of the University of Reading
People from Ilkley
Alumni of the University of Leeds
Food chemists
1927 births
2011 deaths | Harry Nursten | [
"Chemistry"
] | 454 | [
"Food chemists",
"Food chemistry"
] |
58,516,071 | https://en.wikipedia.org/wiki/Radar%20ornithology | Radar ornithology is the use of radar technology in studies of bird migration and in approaches to prevent bird strikes particularly to aircraft. The technique was developed from the observations of pale wisps seen moving on radar during the Second World War. These were termed as "angels", "ghosts", or "phantoms" in Britain and were later identified as being caused by migrating birds. Over time, the technology has been vastly improved with Doppler weather radars that allow the detection of birds, bats, as well as insects with resolution and sensitivity that is sufficient to quantify the speed of flaps that can sometimes aid in the identification of species.
History
According to David Lack, the earliest recorded use of radar in detecting birds came in 1940. The movements of gulls, herons and lapwings that caused some of the detentions was visually confirmed. It was however only in the 1950s through the work of Ernst Sutter at Zurich airport that more elusive "angels" were confirmed to be caused by small passerines. David Lack was one of the pioneers of radar ornithology in England.
Applications
Early radar ornithology mainly focused, due to limitations of the equipment, on the seasonality, timing, intensity, and direction of flocks of birds in migration. Modern weather radars can detect the wing area of the flying, the speed of flight, the frequency of wing beat, the direction, distance and altitude. The sensitivity and modern analytical techniques now allows detection of flying insects as well.
Radar has been used to study seasonal variations in starling roosting behaviour. It has also been used to identify risks to aircraft operations at airports. The technique has been in conservation applications such as being used to assess the risk to birds by proposed wind energy installations, to quantify the number of birds at roost or nesting sites.
References
External links
Radar ornithology
Radar entomology
Biological techniques and tools | Radar ornithology | [
"Biology"
] | 391 | [
"nan"
] |
58,516,445 | https://en.wikipedia.org/wiki/Neurogenic%20bowel%20dysfunction | Neurogenic bowel dysfunction (NBD) is reduced ability or inability to control defecation due to deterioration of or injury to the nervous system, resulting in fecal incontinence or constipation. It is common in people with spinal cord injury (SCI), multiple sclerosis (MS) or spina bifida.
The gastrointestinal tract (GI tract) has a complex control mechanism that relies on coordinated interaction between muscular contractions and neuronal impulses (nerve signals). Fecal incontinence or constipation occurs when there is a problem with normal bowel functioning. This could be for a variety of reasons. The normal defecation pathway involves contractions of the colon which helps mix the contents, absorb water and propel the contents along. This results in feces moving along the colon to the rectum. The presence of stool in the rectum causes reflexive relaxation of the internal anal sphincter (rectoanal inhibitory reflex), so the contents of the rectum can move into the anal canal. This causes the conscious feeling of the need to defecate. At a suitable time the brain can send signals causing the external anal sphincter and puborectalis muscle to relax as these are under voluntary control and this allows defecation to take place.
Spinal cord injury and other neurological problems mostly affect the lower GI tract (i.e., jejunum, ileum, and colon) leading to symptoms of incontinence or constipation. However, the upper GI tract (i.e., esophagus, stomach, and duodenum) may also be affected and patients with NBD often present with multiple symptoms. Research shows there is a high prevalence of upper abdominal complaints, for example a study showed that approximately 22% of SCI patients reported feeling bloated, and about 31% experienced abdominal distension.
Signs and symptoms
In NBD there may be fecal incontinence, constipation, or both combined. One type of constipation which may occur in people with NBD is obstructed defecation.
NBD may reduce quality of life as it often leads to difficulties with personal relationships and social life, and may also reduce self-esteem and independence. Fecal incontinence may increase the risk of depression and anxiety.
Causes
Different neurological disorders affect the GI tract in different ways:
Spinal cord injury
Bowel dysfunction caused by a spinal cord injury will vary greatly depending on the severity and level of the spinal cord lesion. In complete spinal cord injury both sensory and motor functions are completely lost below the level of the lesion so there is a loss of voluntary control and loss of sensation of the need to defecate. An incomplete spinal cord injury is one where there may still be partial sensation or motor function below the level of the lesion.
Colorectal dysfunction due to spinal cord injury can be classified in to two types: an upper motor neuron lesion or lower motor neuron lesion. Problems with the upper motor neuron in a neurogenic bowel results in a hypertonic and spastic bowel because the defecation reflex centre, which causes the involuntary contraction of muscles of the rectum and anus, remains intact. However, the nerve damage results in disruption to the nerve signals and therefore there is an inability to relax the anal sphincters and defecate, often leading to constipation. An upper motor neuron lesion is one that is above the conus medullaris of the spinal cord and therefore above vertebral level T12. On the other hand, a lower motor neuron lesion can cause areflexia and a flaccid external anal sphincter so most commonly leading to incontinence. Lower motor neuron lesions are damage to nerves that are at the level of or below the conus medullaris and below vertebral level T12. However, both upper and lower motor neuron disorders can lead to constipation and/ or incontinence.
Spinal cord injury above the S2, S3, S4 level results in preserved reflexes in the rectum and anal canal. Hence the sphincter will remain contracted. Spinal cord injury below this level results in absent reflexes. In this situation, the rectum will be flaccid and the sphincter will be relaxed.
Spina bifida
Patients with spina bifida have a neural tube that has failed to completely form. This is most commonly in the lower back area in the region of the conus medullaris or cauda equina. Therefore, spina bifida affects the bowel similarly to a lower motor neuron spinal cord injury, resulting in a flaccid, unreactive rectal wall. The anal sphincter does not contract and close, leading to stool leakage. Most patients with spina bifida also have hydrocephalus which may result in intellectual deficits, thereby potentially contributing to fecal incontinence.
Multiple sclerosis
There are a variety of symptoms associated with multiple sclerosis that are all caused by a loss of myelin, the insulating layer surrounding the neurons (nerve cells). This means the nerve signals are interrupted and are slower. This causes muscle contractions to be irregular and fewer, resulting in an increased colon transit time. The feces stay in the colon for a longer period of time, meaning that more water is absorbed. This leads to harder stools and therefore increases the symptoms of constipation. This neurological problem can also result in reduced sensation of rectal filling and weakness of the anal sphincter because of weak muscular contraction so can cause stool leakage. In patients with multiple sclerosis, constipation and fecal incontinence often coexist, and they can be acute, chronic or intermittent due to the fluctuating pattern of MS.
Brain lesion
Damage to the defecation centre within the medulla oblongata of the brain can lead to bowel dysfunction. A stroke or acquired brain injury may lead to damage to this centre in the brain. Damage to the defecation centre can lead to a loss of coordination between rectal and anal contractions and also a loss of awareness of the need to defecate.
Parkinson's disease
This condition differs as it affects both the extrinsic and enteric nervous systems due to the decreased dopamine levels in both. This results in less smooth muscle contraction of the colon, increasing the colon transit time. The reduced dopamine levels also causes dystonia of the striated muscles of the pelvic floor and external anal sphincter. This explains how Parkinson's disease can lead to constipation.
Diabetes mellitus
Twenty percent of people with diabetes mellitus experience fecal incontinence due to irreversible autonomic neuropathy. This is due to the high blood glucose levels over time damaging the nerves, which can lead to impaired rectal sensation.
Mechanism
There are different types of neurons involved in innervating the lower GI tract these include: the enteric nervous system; located within the wall of the gut, and the extrinsic nervous system; comprising sympathetic and parasympathetic innervation. The enteric nervous system directly controls the gut motility, whereas the extrinsic nerve pathways influence gut contractility indirectly through modifying this enteric innervation. In almost all cases of neurogenic bowel dysfunction it is the extrinsic nervous supply affected and the enteric nervous supply remains intact. The only exception is Parkinson's disease, as this can affect both the enteric and extrinsic innervation.
Defecation involves conscious and subconscious processes, when the extrinsic nervous system is damaged either of these can be affected. Conscious processes are controlled by the somatic nervous system, these are voluntary movements for example the contraction of the striated muscle of the external anal sphincter is instructed to do so by the brain, which sends signals along the nerves innervating this muscle. Subconscious processes are controlled by the autonomic nervous system; these are involuntary movements such as contraction of the smooth muscle of the internal anal sphincter or the colon. The autonomic nervous system also provides sensory information; this could be about the level of distension within the colon or rectum.
Diagnosis
In order to correctly manage neurogenic bowel dysfunction it is important to accurately diagnose it. This can be done by a variety of methods, the most commonly used would be taking a clinical history and carrying out physical examinations which may include: abdominal, neurological and rectal examinations. Patients may use the Bristol Stool Chart to help them describe and characterise the morphological features of their stool, this is useful as it gives an indication of the transit time. An objective method used to evaluate the motility of the colon and help with diagnosis is the colon transit time. Another helpful test to diagnose this condition may be an abdominal X-ray as this can show the distribution of feces and show any abnormalities with the colon, for example a megacolon. Methods used for diagnosis may vary depending on if the patient is ncontinent or constipated.
Management
Management and treatment for neurogenic bowel dysfunction depends on symptoms and biomedical diagnosis for cause of the condition. General practitioners will often refer patients to gastroenterologist to effectively manage the neurogenic bowel dysfunction. Research has been conducted on a variety of therapy and treatments for neurogenic bowel dysfunction including: diet modification, laxatives, magnetic and electrical stimulation, manual evacuation of feces and abdominal massage, enemas, and pulsed irrigation evacuation (PIE). Efficacy studies for pulsed irrigation evacuation with PIEMED demonstrated favorable results, removing stool of 98% of patients who used it for ineffective bowel routine, symptomatic impaction, or asymptomatic impaction. In the most severe of cases of neurogenic bowel dysfunction induced fecal impaction, surgical interventions like colostomy are used to disrupt the dense mass of stool.
See also
Obstructed defecation
References
Gastrointestinal tract disorders
Defecation
Gastrointestinal motility disorders | Neurogenic bowel dysfunction | [
"Biology"
] | 2,131 | [
"Excretion",
"Defecation"
] |
58,516,900 | https://en.wikipedia.org/wiki/Dimethylcarbamoyl%20fluoride | Dimethylcarbamoyl fluoride is a chemical compound that can be produced by fluorination of dimethylcarbamoyl chloride with potassium fluoride. It is a colorless liquid that is soluble and stable in water.
Dimethylcarbamoyl fluoride is a potent cholinesterase inhibitor and is lethal even at low doses.
See also
Dimethylcarbamoyl chloride
References
Acyl fluorides
Acetylcholinesterase inhibitors | Dimethylcarbamoyl fluoride | [
"Chemistry"
] | 102 | [
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
58,517,372 | https://en.wikipedia.org/wiki/Botryotrichum%20piluliferum | Botryotrichum piluliferum is a fungal species first identified in 1885 by Saccardo and Marchal. It was discovered to be the asexual state of a member of the ascomycete genus, Chaetomium. The name B. piluliferum now applies to the fungus in all its states. B. piluliferum has been found worldwide in a wide range of habitats such as animal dung and vegetation. The colonies of this fungus start off white and grow rapidly to a brown colour. The conidia are smooth and white. B. piluliferum grows optimally at a temperature of 25–30 °C and a pH of 5.5.
History and taxonomy
Botryotrichum piluliferum was first described in Belgium from rabbit dung. The anamorph was discovered by Pier Andrea Saccardo and Marchal in 1885. The teleomorph, Chaetomium piluliferum was named by J. Daniels in 1961 from a culture of B. piluliferum on cellulose film. The culture produced underdeveloped perithecia typical of those seen in the genus Chaetomium but was not connected to any known species at the time. The culture also produced phialospores and dark hyphae that were characteristic of B. piluliferum. Daniels described this as the teleomorph of B. piluliferum and named it C. piluliferum.
A dried type specimen of the teleomorph was studied and found to be similar to C. murorum, a species described by Corda in 1837. This fungus contained narrower ascospores, longer hairs of ascomata, and was absent of aleurioconidia and an anamorph. The conidiophores of C. piluliferum resemble that of C. piluliferoides which was discovered by Udagawa and Horie in 1975. C. piluliferoides produces aleurioconidia 5–7.5 μm in diameter and ascomata that are 200–240 x 120–145 μm containing short terminal hairs of 200–250 μm and spindle-shaped ascospores.
Hawksworth stated that understanding C. piluliferum could not be done using only the anamorph and expressed the need for further research on the Botryotrichum states which occur in three Farrowia and eight other Chaetomium species. C. piluliferum has the most complex conidiophores, (sub)hyaline aleurioconidia, and a thick wall. The others, such as B. atrogriseum, discovered by van Beyma in 1928 and B. peruvianum, discovered by Matsushima in 1975 have similar-sized aleurioconidia and are pigmented.
Growth and morphology
The colonies of B. piluliferum are fast-growing. They can spread from 2.0 to 4.3 cm in diameter in one week when grown at . The colonies start off as white aerial mycelium which can become a yellowish-beige colour by the subsequent production of brown, rough-walled sterile setae. These brown setae are about 250 x 2–5 μm and bumpy or encrusted near their base. The conidiophores branch at right angles to the main axis. They are smooth, colourless, and produce conidia at their ends. The conidia are thick-walled, hyaline (white), smooth, and spherical. They are approximately 9–16 μm in diameter. B. piluliferum also contains branched hyaline conidiophores that produce aleurioconidia in clusters. The aleurioconidia are globose and typically 3.0–3.5 μm thick. The fungus can produce chains of phialoconidia as well. Ascomata in B. piluliferum are rare and reach maturity in four weeks at . They are black, with a globose to subglobose shape. The lateral and terminal hairs of the ascomata are 500–1500 μm long, 4–6 μm wide with an olive-brown colour and may contain tips with are rolled in a flat coil towards the center. The pale brown ascospores are ellipsoidal (or football-shaped) and contain one germ pore that is roughly 13–16 x 8–10.5 μm.
Mating behaviour of the fungus is unknown because single-spore cultures lose the ability to produce ascomata. The teleomorph C. piluliferum is made up of colonies containing brown hyphae with rough and bumpy hairs. C. piluliferum ascomata are superficial and spherical or obovate (oval-shaped with a narrow base, like a light bulb. They contain a small pore on the top called and ostiole that allow spores to pass through. The perithecia have brown or reddish walls and are covered with thick-walled, septate ascomatal hairs that are long, brown, with many bends and turns, often with tightly coiled tips. The asci are obovate (light bulb-shaped) or broadly clavate (baseball bat-shaped), have a short stalk and contain 8 spores. Phialoconidia form from the apex towards the base in the form of droplets on clustered flask-shaped cells.
Physiology
Botryotrichum piluliferum has an optimal growth temperature range of , with its maximum growth temperature at . The fungus cannot tolerate acid. It can grow in alkaline pH greater than 8.8, however its optimal pH is 5.5. This allows for decomposition of starch, pectin and xylan. B. piluliferum produces mycotoxins that are metabolically similar to aflatoxin. A mycotoxin isolated from B. piluliferum, sterigmatocystin, is involved in the synthesis pathway of aflatoxin. In comparison to other species like Trichoderma aureoviride, that has been found to be very susceptible to parasites, B. piluliferum shows greater resistance to mycoparasites such as Pythium oligandrum. B. piluliferum also produces the metabolite cochliodinol A.
Habitat and ecology
Botryotrichum piluliferum is found worldwide. It has been isolated and recorded in many countries such as Canada, the United States, The Netherlands, and South Africa. It has been found on deer and goat dung in Denmark and field mouse dung in England. The fungus is rarely found in soils, however, it can be found at depths of 80 cm below soil. It has been reported in mountainous regions, salt marshes, and cedar forests. It has also been isolated from stems of Urtica dioica, hay, rhizospheres of groundnut, rice and wheat, paper products, and mouldy textiles, as well as in the seeds of chili pepper. B. piluliferum is a food source for Pygmephorus mesembrinae and P. quadratus. When in vitro, it can be parasitized by Pythium oligandrum.
References
Sordariales
Fungi described in 1885
Fungus species | Botryotrichum piluliferum | [
"Biology"
] | 1,536 | [
"Fungi",
"Fungus species"
] |
65,261,724 | https://en.wikipedia.org/wiki/Polycon | In geometry, a polycon is a kind of a developable roller. It is made of identical pieces of a cone whose apex angle equals the angle of an even sided regular polygon. In principle, there are infinitely many polycons, as many as there are even sided regular polygons. Most members of the family have elongated spindle like shapes. The polycon family generalizes the sphericon. It was discovered by the Israeli inventor David Hirsch in 2017.
Construction
Two adjacent edges of an even sided regular polygon are extended till they reach the polygon's axis of symmetry that is furthest from the edges' common vertex.
By rotating the two resulting line segments around the polygon's axis of symmetry that passes through the common vertex, a right circular cone is created.
Two planes are passed such that each one of them contains the normal to the polygon at its center point and one of the two distanced vertices of the two edges.
The cone part that lies between the two planes is replicated times, where is the number of the polygon's edges. All parts are joined at their planer surfaces to create a spindle shaped object. It has curved edges which pass through alternating vertices of the polygon.
The obtained object is cut in half at its plane of symmetry (the polygon's plane).
The two identical halves are reunited after being rotated at an offset angle of
Edges and vertices
A polycon based on a regular polygon with edges has vertices, of which coincide with the polygon's vertices, with the remaining two lying at the extreme ends of the solid. It has edges, each one being half of the conic section created where the cone's surface intersects one of the two cutting planes. On each side of the polygonal cross-section, edges of the polycon run (from every second vertex of the polygon) to one of the solid's extreme ends. The edges on one side are offset by an angle of from those on the other side. The edges of the sphericon () are circular. The edges of the hexacon () are parabolic. All other polycons' edges are hyperbolic.
The sphericon as a polycon
The sphericon is the first member of the polycon family. It is also a member of the poly-sphericon and the convex hull of the two disc roller (TDR convex hull) families. In each of the families, it is constructed differently. As a poly-sphericon, it is constructed by cutting a bicone with an apex angle of at its plane of symmetry and reuniting the two obtained parts after rotating them at an offset angel of .
As a TDR convex hull it is the convex hull of two perpendicular 180° circular sectors joined at their centers. As a polycon, the starting point is a cone created by rotating two adjacent edges of a square around its axis of symmetry that passes through their common vertex. In this specific case there is no need to extend the edges because their ends reach the square's other axis of symmetry. Since, in this specific case, the two cutting planes coincide with the plane of the cone's base, nothing is discarded and the cone remains intact. By creating another identical cone and joining the two cones together using their flat surfaces, a bicone is created. From here the construction continues in the same way described for the construction of the sphericon as a poly-sphericon. The only difference between the sphericon as a poly-sphericon and sphericon as a polycon is that as a poly- sphericon it has four vertices and as a polycon it is considered to have six. The additional vertices are not noticeable because they are located in the middle of the circular edges, and merge with them completely.
Rolling properties
The surface of each polycon is a single developable face. Thus the entire family has rolling properties that are related to the meander motion of the sphericon, as do some members of the poly-sphericon family. Because the polysphericons' surfaces consist of conical surfaces and various kinds of frustum surfaces (conical and/or cylindrical), their rolling properties change whenever each of the surfaces touches the rolling plane. This is not the case with the polycons. Because each one of them is made of only one kind of conical surface the rolling properties remain uniform throughout the entire rolling motion. The instantaneous motion of the polycon is identical to a cone rolling motion around one of its central vertices. The motion, as a whole, is a combination of these motions with each of the vertices serving in turn as an instant center of rotation around which the solid rotates during of the rotation cycle. Once another vertex comes into contact with the rolling surface it becomes the new temporary center of rotation, and the rotation vector flips to the opposite direction. The resulting overall motion is a meander that is linear on average. Each of the two extreme vertices touches the rolling plane, instantaneously, times in one rotation cycle. The instantaneous line of contact between the polycon and the surface it is rolling on is a segment of one of the generatinglines of a cone, and everywhere along this line the tangent plane to the polycon is the same.
When is an odd number this tangent plane is a constant distance from the tangent plane to the generating line on the polycon surface which is instantaneously uppermost. Thus the polycons, for odd, are constant height rollers (as is a right circular bicone, a cylinder or a prism with Reuleaux triangle cross-section). Polycons, for even, don't possess this feature.
History
The sphericon was first introduced by David Hirsch in 1980 in a patent he named 'A Device for Generating a Meander Motion'. The principle, according to which it was constructed, as described in the patent, is consistent with the principle according to which poly-sphericons are constructed. Only more than 25 years later, following Ian Stewart's article about the sphericon in the Scientific American Journal, it was realized both by members of the woodturning [17, 26] and mathematical [16, 20] communities that the same construction method could be generalized to a series of axial-symmetric objects that have regular polygon cross sections other than the square. The surfaces of the bodies obtained by this method (not including the sphericon itself) consist of one kind of conic surface, and one, or more, cylindrical or conical frustum surfaces. In 2017 Hirsch began exploring a different method of generalizing the sphericon, one that is based on a single surface without the use of frustum surfaces. The result of this research was the discovery of the polycon family. The new family was first introduced at the 2019 Bridges Conference in Linz, Austria, both at the art works gallery and at the film festival
References
Geometric shapes
Euclidean solid geometry | Polycon | [
"Physics",
"Mathematics"
] | 1,433 | [
"Geometric shapes",
"Euclidean solid geometry",
"Mathematical objects",
"Space",
"Geometric objects",
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65,262,091 | https://en.wikipedia.org/wiki/Social%20media%20and%20identity | Social media can have both positive and negative impacts on a user's identity. Psychology and Communication scholars study the relationship between social media and identity in order to understand individual behavior, psychological impact, and social patterns. Communication within political or social groups online can result in practice application of those identities or adoption of them as a whole. Young people, defined as emerging adults in or entering college, especially shape their identities through social media.
Young adults
At the stage where a young adult becomes an emerging adult, individuals are especially influenced by social media. Psychologists study methods of self-presentation to determine how a user's patterns and media participation affects their own identity. Young adults, through media literacies, can also find their identity as a part of a social group, such as feminists. These studies are connected to building frameworks for educators on teaching media literacies. Due to their fluency in media literacy, young people often contribute to these larger social identities through their networks, and unique style of communication when sharing information.
Young Individuals have been found to be affected by what they take in on Social Media. Psychologists believe that at a time when young adults are coming into adolescence, they are more likely to be influenced by what they see on sites like Instagram or Twitter. More so directed towards the times of Identity Formation, as these individuals are impressionable and still creating their identity. With the advance of social media, most young adults will widely share, with varying degrees of accuracy, honesty, and openness, information that in the past would have been private or reserved for select individuals. Key questions include whether they accurately portray their identities online and whether the use of social media might impact young adults’ identity development. Media Imagery, in particular, is said to be a major influence on the minds of young men and women. Studies have shown that it is even more relevant when it comes to the issue of body image. Social Media, in part, has been created to host a safe haven for those who do not claim a solid identity in the material world, giving them a chance for exploration of other identities in the virtual concept. Psychologists and Scholars have noted that while past identities are not easy to escape from; the Internet is more permanent.
Social media is an essential part of the social lives of young adults. They rely on it to maintain relationships, create new relationships, and stay up to date with the world around them. Adolescents find social media to be extremely helpful when changing environments, like moving off to university for example. Social media provides students, especially first year students, the opportunity to create the identity they want the world to see. However, it has been seen that these students create online personas that may not reflect their true selves bringing up the issues of impression management. Social media provides young adults with the opportunity to present themselves as something other than their authentic self.
Media literacy
The definition of media literacy has evolved over time to encompass a range of experiences that can occur in social media or other digital spaces. The definition of media literacy is also broad and wide ranging in its context.
Currently, media literacy includes being able to understand, apply, and share digital images and messages. Educators teach media literacy skills because of the vulnerable relationship that young adults can have with social media. Some examples of media literacy practices, particularly on Twitter, include using hashtags, live tweeting, and sharing information. Overall, the goal of media literacy within social media is to keep young adults aware of potentially violent, graphic, or dangerous content that they may come across on the internet, and how to handle it with responsibility and safety in mind.
In order to be considered media-literate, a person must be able to take in media from online and social platforms and have the correct competencies and context to be able to organize the information. In order to be considered media-literate, the digital information must be given to the user in a way that it can be put into the correct perspective and analyzed, deducted and synthesized. Teenagers and young adults can be vulnerable to specific content online outside of their age-range. Media literacy campaigns and education research shows that targeting those who fall into this age category would be the best way to understand and target their needs as young online users.
There are multiple individual studies investigating social media identity relating to media literacy online, however there is a need for much more conclusive information that analyzes multiple studies at a time. Social media literacy is still considered an under-researched topic. Many scholars in media literacy research emphasize the impact of training young adults to consume media in a safe way is the major solution for furthering internet education in children and young adults. The more information the young adults are given on media literacy, the better prepared they are to enter the digital world confidently.
One scientific model that has been proposed, known as The Social Media Literacy (SMILE) model. This framework hypothesizes that at the core of this model is helping young adults truly know the meaning and display the actions of media literacy online. SMILE is also meant to inspire more research on the subject of media literacy as it relates to social media effects and young adult leaning abilities. The model was applied through the lens of a social media positivity bias among adolescents and puts forth five different assumptions about social media and media literacy;
Social media literacy as a moderator (what is seen on social media)
Social media literacy as a predictor (what is seen for specific individuals on social media)
Media literacy within social media is a reciprocal process
The development of social media literacy depends on a conditional process of variables affecting other variables
Media literacy within social media is a differential learning process, and who teaches it is highly affective of the outcome
This model also stresses that human beings learn media literacy (and social media literacy) naturally as they go through life. Research suggests that having young adults taught media literacy from an educator may make them less interested (and therefore less careful) of threats on social media.
Self Presentation
People create images of themselves to present to the public, a process called self presentation. Depending on the demographic, presenting oneself as authentic can result in identity clarity. Methods of self presentation can also be influenced by geography. The framework for this relationship between a user's location and their social media presentation is called the spatial self. Users depict their spatial self in order to include their physical space as a part of their self presentation to an audience.
In a 2018 research paper, it shares that patients of plastic surgeons have gone in and asked for specific snapchat "filter" features. This led to a theory of Snapchat Dysmorphia. Since the introduction to snapchat in 2011, more and more people each year are going into doctor offices and asking for smoother skin, bigger eyes, and fuller lips. It is creating a disconnect from who they are and who they want to be.
Social comparison theory is the idea that people are likely to compare themselves to people who are similar to them. Influencers have impacted this idea, we often watch people on the internet that we feel we can relate too. Within this theory there is 2 subcategories; Upward and downward comparison. Upward comparison is the idea that someone compares themselves to someone they feel is better than they are. Downward is the opposite, they compare themselves to someone they feel is worse off.
Cultivation theory is the more often people are going to be exposed to images of society's ideal body, the less they are going to realize the images are unrealistic
Self Schema Theory is the idea women use three points to determine how they view themself
Socially ideal: ideal ways women are represented in media
Objective body: how we view our own self
Internalized ideal body: Internalizing media and how much they want to achieve it
Pescott (2020) study found that the use of Snapchat filters in preteens has a great impact on how they present themselves online. Boys found filters to be more fun and used for entertainment, whereas girls used filters more as a beauty enhancer. This becomes dangerous for preteens who are not aware of when a filter is being used when consuming content from friends, influencers, or celebrities. The same study found that the use of filters can have a large impact on preteens’ identity formation as they begin to compare themselves with others.
Influences on Body Image
In comparison to traditional forms of media, where individuals could only act as consumers of media, social media networking sites provide a more engaging opportunity where users can produce their own content, as well as interact with other users and content creators. As these sites have become increasingly popular, researchers have turned their focus to the discussion of the various impacts social media has on users. One of the main focuses researchers have studied is the effects on body image. This is especially seen in adolescents and young adults who engage in social media.
It has been suggested that in the early adolescent years, when perceptions about self and identity are being formed, individuals may be influenced by the media to feel certain ways about their bodies based on the ideal body types expressed and perpetuated in the media, which may increase body surveillance behaviors and, consequently, experiencing feelings of body shame. Salomon & Brown (2019), measured self-objectification behaviors on social media, body surveillance behaviors, feelings of body shame, and levels of self-monitoring to examine whether or not young adolescents engaging in higher amounts of self-objectification behaviors on social media also experienced higher levels of body shame.
Self-objectification behaviors result from internalizing objectification from others, and may, for example, take the form of taking frequent photos of oneself and valuing how others view their appearance. Body surveillance behaviors indicate a preoccupation with how the appearance of one’s body will be perceived by others and can be measured by behaviors such as constant evaluation and monitoring of one’s body. Body shame refers to a negative emotional experience resulting from feeling as if one failed to meet society’s body ideals. Self-monitoring refers to how much individuals do or do not change their behavior in response to feedback and cues received from peers. In the study, it was found that individuals who reported engaging in self-objectified social media use exhibited more body surveillance behaviors, which led to increased experience in feelings of body shame.
Some studies have demonstrated that body image is not influenced by how much time is spent on social media, but is influenced by the way an individual engages with the site. For instance, Meier and Gray (2014), measured Facebook usage among young women and found that those who more frequently viewed posts of images and videos were more likely to experience negative thoughts about their own body image and internalize the thin ideal. However, it is seen that Facebook did not influence body image itself. More interacting on Facebook, in regards to posting, commenting and viewing, causes women, specifically high school females to have greater weight dissatisfaction, drive for thinness, thin-ideal internalization and self objectification. Having more of an opportunity to compare yourself to other people on social media can cause people to feel like they should look that way. Facebook posts more than 10 million photos an hour, so having many examples of an idealistic body-type tempts viewers to compare their bodies to their own.
In response to self-portraits on social media, friends and followers can indicate affirmation and acceptance, and creators can receive validation, through feedback such as likes and comments. According to the findings of Bukowski, Dixon, and Weeks (2019), the more value that an individual placed on the feedback received on a self-portrait that they’ve shared, the more they experience body dissatisfaction and a desire to become thinner, but only if they also engage in body-surveillance.
Studies have shown that users can also experience feelings of body dissatisfaction when consuming rather than creating content. In a study conducted by Fardouly, et al. (2015), the implications of Facebook usage on young women’s mood, level of body dissatisfaction, and desires to change aspects of their body or facial features were examined. The results of the study indicated that in addition to Facebook usage being associated with a more negative mood, it was associated with an increasing desire to change facial related features in women who were more likely to make comparisons between elements of their and others appearance.
Platform Affordances
The different platform affordances of social media sites can both enable and constrain the options users have for presenting themselves. Initially coined by Gibson (1966), Affordances, broadly, can be defined as “describing what material artifacts such as media technologies allow people to do”. This can therefore be applied to how users of social media construct identity, through the ways in which social media sites provide users with opportunities for self-presentation.
For example, Instagram requires users to create a profile when they register an account. In this, they require a username, profile photo, biography and more recently, the option to present the users chosen pronoun. However, none of these identifiable aspects need to be factual, and unlike Facebook, which requires users to register with their legal name, Instagram users can use pseudonyms or made-up usernames and profile pictures. This gives them the ability to construct whichever identity they choose to present.
Media Reactions Within Companies
Frank J Lexa and David Fessell managed to test and review a hypothetical question given to a group of MD’s from various universities. The question asks if a key radiologist posted a media post that involved a racial epithet and a younger colleague brought this to your attention, what would you do? Response replies varied, but almost all had one common theme/connection that connected to points made by Darren L Linvell in discussing the dangers of social media. Linvell made a point to bring up how digital civility is key in producing healthy online dynamics and connections. The respondents within Frank J Lexas and David Fessells test, answered by saying how immediate communication would take place to set the basics of the situation down. This focuses on creating civility through proper communication. Another connection seen is that in case of media controversies, training and policy making methods would take place such as sensitivity training. Other policies would take place depending on what specific policies a certain workplace may have. So, within work settings, it is seen to be important to first make sure an establishment has already implemented policy making methods for various cases, and also create an employee board that is able to demonstrate and carry out digital civility.
Increased Policymaking
The creation of social media has brought along with it various ways for people all around the world to communicate. This media has created a system for all kinds of peoples to connect, create new and improved identities, improve relationships, share information, and be able to reach out into a world of new opportunities. This same media has also given way for young adolescents to access their way into a world of mental health issues, negative self image, racial hostility, cyberbullying, sexual harassment, stalking, and even suicide.
As social media continues to fall into the hands of younger children, it is necessary to implement policy making strategies in order to decrease the rate of harm towards adolescents who are more susceptible and fall victim to the dangers that are presented with social media use so it is necessary to implement. 13 year old girls are given access to view methods on how to consume under 300 calories a day through Tik Tok, but youth within the U.S. has been having access to these various kinds of platforms for some while now. Adolescents consuming unhealthy media leads to mental health issues revolving around depression, eating disorders, and sometimes even leading to suicide. Due to this, a research program by the name The Strategic Training Initiative for the Prevention of Eating Disorders (STRIPED) has begun to study the dangerous and harmful effects of social media platforms and how we are able to regulate social media's presentation of harmful content. It has been found that $11 billion revenue has been made from users ages 0-17 through advertisement methods which is why companies continue to display harmful content to youth.
Policymaking may be a way to regulate social media platforms, but certain legal obstacles make it difficult to provide regulation. First, The First Amendment protects the rights of social media platforms since social media is just a computer code, individuals attempting to regulate media speech, are at risk of violating this law. As for Section 230 of the Communications Decency Act (CDA), online services are provided with protection and are not responsible for the speech produced by the 3rd party individuals who are using the platform. Due to this, new laws created for social media safety have to be careful not to overrun and violate the currently standing laws such as the First Amendment. So, it is important to require companies to have algorithm risk audits which are approaches that review media processing systems through testing media outputs or documentations in order to protect the wellbeing of the youth and diminish the risk of danger.
Darren L Linvell discusses the “dark side” of social media which is the dangers that are brought along to students within and beyond a college campus. Social media use within students in the college age range use social media as a way to be able to display themselves. Some students choose to display their authentic selves, while others choose to create a different persona to present to surrounding peers. But, social media does come with its dangers such as cyberbullying, racial hostility, aggression, stalking, et. When students present whichever persona they display publicly online, they are at risk of falling victim to cyberbullying. Cyberbullying produces a larger number of bystanders than physical bullying as it is seen as less serious and that the victim brought on the situation to themselves. But, both cyberbullying and physical bullying have the same unfortunate outcomes such as mental health impacts and even suicide. The importance of the idea of teaching social media literacy to students to increase levels of safety within social media through education. Students may not always care to engage in this method, so it is more recommended to focus on the process and communication that occurs in order to give the result of certain information when engaging with information given. Another main focus is also the concept of digital civility as it requires creating healthy relationships through building mutual understanding with each other by learning to communicate properly. Rather than focusing on teaching students all aspects of social media literacy/safety, the light focuses on human communication skills because students are more likely to be engaged and educated more from this method to develop higher social media literacy.
Since it is difficult to implement legal policymaking actions against media dangers, the APA has released recommendations which discuss various methods that families may try to improve social media safety. Recommendations vary from stating that adolescents should be educated in social media literacy which is done through the SMILE method. But looking back at points made by Darren L Linvell, this method may make students less interested in being educated on it which results in unsafe media consumption behavior. Other recommendations discuss that setting limitations may decrease intake of harmful content which leads to adolescents engaging in eating disorder behavior, negative self image, and violence. Another goal of limitation is to aid adolescents in keeping up a healthy sleep schedule and physical activity engagement. But, recommendations may not work for every family, which is why some releases as well as clinicians state that rules should be made based on an individual's intellectual stage/knowledge. This connects to the importance of keeping up a healthy family dynamic, which is why parents should aim to understand their children's weaknesses and strengths within knowledge on social media use. Parents need to understand their children and have trust in them that they will use social media safely. Families can discuss together what limitations may be implemented within media use and that way adolescents will not feel unmotivated to use media in a harmful way as they are able to have a say within media rules and not feel limited by external influences (adults, policies, etc.) This connects to another advisory stated by the APA which discusses that parents should collaborate with teens in order to get them on board to use social media more safely. It is important for adults to support teens' personal interests rather than keeping them limited from it as that may lead to harmful/dangerous behavior that is not in the teens best interest.
Overall, it is seen that unsafe and sometimes even safe media use, can bring upon negative outcomes such as dangers and various threats that young adolescents have to deal with. Various law making policies are attempting to be made, but current laws create an obstruction in that path which make it difficult to create laws to fight media dangers. Due to this, families and adolescents have to take matters into their own hands to protect themselves from media harm. Fortunately, various sources such as the APA give helpful and effective recommendations to help protect themselves. It is important to address privacy and awareness matters when dealing with media use. Social media is a platform that gives access to endless opportunities and possibilities, but in order to keep this progression up, it is necessary to create effective legal policies as well as understand basic media literacy and digital civility.
References
Social media
Social impact
Identity (social science) | Social media and identity | [
"Technology"
] | 4,274 | [
"Computing and society",
"Social media"
] |
65,262,194 | https://en.wikipedia.org/wiki/Teg147 | Teg147 RNA (also known as sRNA85, SAOUHSCs103) is a non-coding RNA identified by RNA-seq in Staphylococcus aureus N315 with homologues in other Staphylococcus species.
References
External links
Non-coding RNA | Teg147 | [
"Chemistry"
] | 65 | [
"Molecular biology stubs",
"Molecular biology"
] |
65,262,268 | https://en.wikipedia.org/wiki/Solar%20eclipses%20after%20the%20modern%20era | This article contains information and statistics about solar eclipses occurring after the modern era, from the 22nd century to the 30th century.
Solar eclipses by century
Longest total eclipses
Below is a list of all total eclipses at least 7 minutes long that will occur between the 22nd and 30th centuries. Of the listed eclipses, the first five are in Solar Saros 139, the next three are in Solar Saros 145, and the final four are in Solar Saros 170.
Notes
References
+22
Future solar eclipses | Solar eclipses after the modern era | [
"Astronomy"
] | 105 | [
"Future astronomical events",
"Future solar eclipses"
] |
65,263,282 | https://en.wikipedia.org/wiki/Maurice%20Newman%20%28artist%29 | Maurice Newman was a painter, sculptor, model maker and photographer. He was the son of Abraham Newman and Tobi Schmukler, and was born in Lithuania in 1898. He was married to Edythe Brenda Tichell from 1930 to his death in 1977. He had one daughter, Rachel Newman.
In his teens, Newman left Lithuania to live in Switzerland, and acted as a messenger, delivering messages between clandestine lovers; he spoke Russian, Lithuanian, Polish, German and Yiddish. He then lived in England and South Africa, attending the National School of Arts in Johannesburg. In the early 1920s, Newman migrated to the U.S., lived in Boston, and worked in the Newton offices of the Bachrach Studios. After a brief stint as a retoucher at the White Studios in New York City, he returned to Boston to work as a commercial artist while attending the Vesper George School of Art, the School of the Museum of Fine Arts (now the School of the Museum of Fine Arts at Tufts), and the Woodbury School of Art.
In 1940, Newman was employed as a model maker by Federal Works of Art Passive Defense Project (Federal Art Project). In 1942 he relocated to Alexandria Virginia as a civilian Army employee to head the model shop in the United States Army Engineer Research and Development Laboratory at Fort Belvoir. During World War II, he constructed dioramas and topographical bombing maps. Following the war, projects shifted to the Cold War and civil defense.
In retirement, Newman was able to fully devote his time to portrait painting, as well as sculptures in wood and aluminum. His aluminum sculpture, one of the first U.S. memorials to the six million Jews martyred by Hitler, was unveiled in 1963 at the Kansas City, Missouri Jewish Community Center; the keynote speaker at the unveiling was former President Harry S. Truman. His dioramas and miniatures were exhibited at the Boston Children's Museum, 1939 New York World's Fair and the Peabody Essex Museum.
References
20th-century American painters
20th-century American sculptors
20th-century American male artists
1898 births
1977 deaths
Federal Art Project artists
American male painters
American male sculptors
Jewish American painters
Scale modeling
Visual arts genres
American people of Lithuanian-Jewish descent
American artists
20th-century American Jews
Emigrants from the Russian Empire to the United States | Maurice Newman (artist) | [
"Physics"
] | 473 | [
"Scale modeling"
] |
65,263,587 | https://en.wikipedia.org/wiki/NGC%203073 | NGC 3073 is a dwarf lenticular galaxy in the constellation Ursa Major. It is at a distance of about 65 million light-years (20 megaparsecs) from Earth. NGC 3073 was discovered by German-British astronomer William Herschel on 1 April 1790.
NGC 3073 belongs to the NGC 3079 Group (also known as LGG 188), which contains six galaxies. The other galaxies in the group are NGC 3079, UGC 5421, UGC 5479, UGC 5459, and UGC 5460. The galaxies NGC 3073 and NGC 3079 are also listed together as Holm 156 in Erik Holmberg's A Study of Double and Multiple Galaxies Together with Inquiries into some General Metagalactic Problems, published in 1937.
Gallery
See also
List of NGC objects (3001–4000)
References
External links
Ursa Major
3073
05374
+09-17-007
028974
Lenticular galaxies
0131
Discoveries by William Herschel
17900401 | NGC 3073 | [
"Astronomy"
] | 209 | [
"Ursa Major",
"Constellations"
] |
65,266,320 | https://en.wikipedia.org/wiki/Fertiliser%20use%20in%20Nepal | Agriculture is the main GDP contributor for the economy of Nepal and fertilisers play a vital role. The annual average fertiliser requirement in Nepal to replenish the soil nutrition is 310 kg per hectare but only 29 kg of fertiliser is added to the soil. Fifty per cent of nutrient loss from the soil occurs during the early monsoon.
The use of fertiliser is relatively new to Nepal. Up to the 1950s, chemical fertilisers were not used in Nepal and all fertilizers were organic, produced locally. Currently, both organic and chemical fertilisers are used.
Organic fertilisers
Organic fertilisers are produced locally by recycling agricultural waste and animal waste. In hilly farms, compost and farm yard manure are the traditional source of fertiliser.
Government supports the use of organic fertiliser. It has adopted a policy to promote organic fertilisers. The Ministry of Agriculture provides a subsidy to the farmers purchasing the organic fertilisers at a rate of NPR 10 per kg or 50% of the sales price whichever is low. Similarly, the organic fertilisers production plant is also subsidised by providing 50% of the cost.
There are 25 centres that produce organic fertilisers with the total annual capacity of 100,600 MT (2015 AD). Some of the major ones are listed in the table. Besides, some portion of inorganic fertilizer is imported from abroad.
Chemical fertilisers
The use of chemical fertiliser is relatively new in Nepal. In the 50s, a small quantity of ammonium sulphate used to be imported from India. It was followed by importing from Russia by the National Trading Limited (a government agency) up to the mid-sixties To facilitate the import and distribution of fertilisers, Agriculture Inputs Corporation (AIC) was established under the Ministry of Agriculture in 1966.
In 1974, the government subsidized the fertiliser to some selected high hills and mid-hills districts due to price rise in the international market. However, the local price was still set 15-20% higher than the neighbouring country (India) to discourage outflow of fertilisers from Nepal. Germany, Canada, Japan and Finland in the late 60s started providing chemical fertiliser to Nepal in the form of aid. However, this did not continue long. By the 1990s only a few countries were providing the fertilizer aid.
In 1997, the government started deregulating the subsidy on fertilisers. By 1999, the subsidy was completely removed from all kinds of fertilisers. This removed the monopoly of AIC and the private sector started to compete in the fertiliser market. To institutionalize the deregulation policy, and to regulate the business under the policy, the government promulgated Fertiliser Control Order in 1999. In 2002, a National Fertiliser Policy was formulated and AIC was divided into two new organization viz. Agriculture Inputs Company Limited (AICL) responsible for fertiliser business and 2) National Seed Company Limited (NSCL). The fertiliser policy was considered to focus on supplying high-quality and affordable fertiliser to farmers.
In November 2008 the government again started to subsidise fertilisers (both organic and chemical) and it was endorsed on 25 March 2009.
Production and import
As of 2020, chemical fertilisers are not produced in Nepal. They are imported mostly from or through India. In the 1980s, there were plans to build the plant and feasibility study were carried out, but the plans have not been implemented. The import of chemical fertilisers (in MT) is shown in the bar-chart.
Types of chemical fertilisers
Mainly seven types of chemical fertilisers are used in Nepal. These are Urea, Diammonium Phosphate (DAP), Murate of Potash (MOP), Ammonium Sulphate (AS), Single Super Phosphate (SSP), Ammonium Phosphate Sulphate (APS) and NPK. The use of chemical fertilisers has an increaseing trend. Among them, Urea and DAP is the most used ones.
Quality
The fertiliser supplied by informal and illegal sources (mainly from India) is considered to have poor quality. Some private traders were found to repack the low-quality imported fertilisers into popular brands.
See also
Agriculture in Nepal
References
Agriculture in Nepal
Fertilizers | Fertiliser use in Nepal | [
"Chemistry"
] | 937 | [
"Fertilizers",
"Soil chemistry"
] |
65,266,370 | https://en.wikipedia.org/wiki/Quantum%20Trajectory%20Theory | Quantum Trajectory Theory (QTT) is a formulation of quantum mechanics used for simulating open quantum systems, quantum dissipation and single quantum systems. It was developed by Howard Carmichael in the early 1990s around the same time as the similar formulation, known as the quantum jump method or Monte Carlo wave function (MCWF) method, developed by Dalibard, Castin and Mølmer. Other contemporaneous works on wave-function-based Monte Carlo approaches to open quantum systems include those of Dum, Zoller and Ritsch, and Hegerfeldt and Wilser.
QTT is compatible with the standard formulation of quantum theory, as described by the Schrödinger equation, but it offers a more detailed view. The Schrödinger equation can be used to compute the probability of finding a quantum system in each of its possible states should a measurement be made. This approach is fundamentally statistical and is useful for predicting average measurements of large ensembles of quantum objects but it does not describe or provide insight into the behaviour of individual particles. QTT fills this gap by offering a way to describe the trajectories of individual quantum particles that obey the probabilities computed from the Schrödinger equation. Like the quantum jump method, QTT applies to open quantum systems that interact with their environment. QTT has become particularly popular since the technology has been developed to efficiently control and monitor individual quantum systems as it can predict how individual quantum objects such as particles will behave when they are observed.
Method
In QTT open quantum systems are modelled as scattering processes, with classical external fields corresponding to the inputs and classical stochastic processes corresponding to the outputs (the fields after the measurement process). The mapping from inputs to outputs is provided by a quantum stochastic process that is set up to account for a particular measurement strategy (e.g., photon counting, homodyne/heterodyne detection, etc.). The calculated system state as a function of time is known as a quantum trajectory, and the desired density matrix as a function of time may be calculated by averaging over many simulated trajectories.
Like other Monte Carlo approaches, QTT provides an advantage over direct master-equation approaches by reducing the number of computations required. For a Hilbert space of dimension N, the traditional master equation approach would require calculation of the evolution of N2 atomic density matrix elements, whereas QTT only requires N calculations. This makes it useful for simulating large open quantum systems.
The idea of monitoring outputs and building measurement records is fundamental to QTT. This focus on measurement distinguishes it from the quantum jump method which has no direct connection to monitoring output fields. When applied to direct photon detection the two theories produce equivalent results. Where the quantum jump method predicts the quantum jumps of the system as photons are emitted, QTT predicts the "clicks" of the detector as photons are measured. The only difference is the viewpoint.
QTT is also broader in its application than the quantum jump method as it can be applied to many different monitoring strategies including direct photon detection and heterodyne detection. Each different monitoring strategy offers a different picture of the system dynamics.
Applications
There have been two distinct phases of applications for QTT. Like the quantum jump method, QTT was first used for computer simulations of large quantum systems. These applications exploit its ability to significantly reduce the size of computations, which was especially necessary in the 1990s when computing power was very limited.
The second phase of application has been catalysed by the development of technologies to precisely control and monitor single quantum systems. In this context QTT is being used to predict and guide single quantum system experiments including those contributing to the development of quantum computers.
It has also been shown that quantum trajectories have full and universal quantum computational power.
Quantum measurement problem
QTT addresses one aspect of the measurement problem in quantum mechanics by providing a detailed description of the intermediate steps through which a quantum state approaches the final, measured state during the so-called "collapse of the wave function". It reconciles the concept of a quantum jump with the smooth evolution described by the Schrödinger equation. The theory suggests that "quantum jumps" are not instantaneous but happen in a coherently driven system as a smooth transition through a series of superposition states. This prediction was tested experimentally in 2019 by a team at Yale University led by Michel Devoret and Zlatko Minev, in collaboration with Carmichael and others at Yale University and the University of Auckland. In their experiment they used a superconducting artificial atom to observe a quantum jump in detail, confirming that the transition is a continuous process that unfolds over time. They were also able to detect when a quantum jump was about to occur and intervene to reverse it, sending the system back to the state in which it started. This experiment, inspired and guided by QTT, represents a new level of control over quantum systems and has potential applications in correcting errors in quantum computing in the future.
References
External links
mcsolve Quantum jump (Monte Carlo) solver from QuTiP for Python.
QuantumOptics.jl the quantum optics toolbox in Julia.
Quantum Optics Toolbox for Matlab
Quantum mechanics
Computational physics
Monte Carlo methods | Quantum Trajectory Theory | [
"Physics"
] | 1,071 | [
"Monte Carlo methods",
"Theoretical physics",
"Quantum mechanics",
"Computational physics"
] |
65,266,916 | https://en.wikipedia.org/wiki/Lark%20Health | Lark Health is an American digital health company based in Mountain View, California. It provides a 24/7 nursing platform for chronic conditions, powered by artificial intelligence (AI) and has a text-messaging type interface. Lark also provides AI nurses for type 2 diabetes care, hypertension care, tobacco cessation, stress management, obesity, and more for 1.5 million patients.
Lark is notable for being preloaded on all Samsung Galaxy S5 phones by 2014.
History
Lark was founded by Julia Hu and Jeff Zira. It first produced a sleep health monitor worn on a person's wrist. It was designed to wake up the individual wearing the device without disturbing anyone else who might be sleeping nearby. The product was soon sold in all Apple stores globally.
Lark eventually focused more on artificial intelligence and less on hardware. By 2014, Lark was preloaded on all Samsung Galaxy S5 phones.
The Lark apps focus on common chronic conditions such as obesity, diabetes prevention, diabetes, and hypertension. Lark Diabetes Prevention Program (DPP) is officially recognized by the Centers for Disease Control and Prevention (CDC) as an online DPP.
Lark's efficacy has been evaluated by a study published in the Journal of Medical Internet Research Diabetes,
Products and services
Lark has specialized health plans focusing on patients with diabetes, hypertension, prediabetes or at high risk for type 2 diabetes, and overall health. Lark's services are delivered and automatically syncs with certain bluetooth-enabled health monitors devices such as home blood pressure monitors, glucometers, activity trackers, and body weight scales. Some programs allow for both the app and one or more connected devices to be used.
References
External links
Companies based in Mountain View, California
Health informatics
Telehealth | Lark Health | [
"Biology"
] | 360 | [
"Health informatics",
"Medical technology"
] |
65,267,036 | https://en.wikipedia.org/wiki/The%20Social%20Dilemma | The Social Dilemma is a 2020 American docudrama film directed by Jeff Orlowski and written by Orlowski, Davis Coombe, and Vickie Curtis. The documentary covers the negative social effects of social media and is interspersed by a dramatized narrative surrounding a family of five who are increasingly affected by problematic social media use.
The Social Dilemma premiered at the 2020 Sundance Film Festival, on January 26, 2020, and was released on Netflix on September 9, 2020, during the COVID-19 pandemic. It received mostly positive reviews from critics, who praised its message and use of interviews with established tech experts but criticized the narrative and lack of nuance in addressing technological problems.
Synopsis
The Social Dilemma covers the psychological underpinnings and manipulation techniques by which, it claims, social media and technology companies addict users. People's online activity is watched, tracked, and measured by these companies, who then use this data to build artificial intelligence models that predict the actions of their users. Tristan Harris, former Google design ethicist and co-founder of the Center for Humane Technology, explains in the documentary that there are three main goals of tech companies:
The engagement goal: to increase usage and make sure users continue scrolling.
The growth goal: to ensure users are coming back and inviting friends, who invite even more friends.
The advertisement goal: to make sure that while the above two goals are happening, the companies are also making as much money as possible from advertisements.
Harris summed this up with the warning: "If you're not paying for the product, you are the product", paraphrasing earlier insights from Television Delivers People, Tom Johnson, and Andrew Lewis.
Another interviewee, Jonathan Haidt, a social psychologist at NYU Stern School of Business, brings up the concerns of mental health in relation to social media.
The film also discusses the dangers of fake news. Harris argues that this is a "disinformation-for-profit business model" and that companies make more money by allowing "unregulated messages to reach anyone for the best price".
In the end credits, the interviewees propose ways the audience can take action to fight back, such as turning off notifications, never accepting recommended videos on YouTube, using search engines that do not retain search history, and establishing rules in the house on cell phone usage.
Narrative
The documentary uses a fictional dramatized narrative to illustrate the issues discussed, centering around "a middle-class, average American family" whose members each interface with the internet differently: Ben, a teenage high school student who falls deeper into social media addiction and online radicalization; Isla, an adolescent who develops depression and low self-esteem from social media's unrealistic beauty standards; Cassandra, an older teenager who does not have a mobile phone and is depicted as being free from online manipulation; and their mother and stepfather, who try to curb their children's screen time but do not fully understand the factors of the situation. The narrative depicts Ben and Isla as increasingly affected by social media and internet addictions, driven by the Engagement, Growth, and Advertisement AIs, represented by anthropomorphized tech executives in a "behind-the-screen" control room, who find ways to keep their users as addicted to social media as possible, while only viewing them as depersonalized avatars, with little concern for theirs or society's well-being.
The narrative starts with Isla ignoring her mother's requests to set the table, followed by her increasingly becoming depressed after her appearance is criticized on social media. After Cassandra criticizes Isla and Ben's problematic smartphone use, their mother proposes locking everyone's phones in a safe so they can have dinner together, but when one phone receives a notification, Isla tries to open the safe and ultimately breaks it open with a tool, damaging Ben's phone screen. In return for a new phone screen, Ben promises his mother he will not use his phone for a week, but the AIs, confused as to why he is suddenly inactive, decide to draw him back in by sending him a notification that his ex has started a new relationship, prompting Ben to break his promise and doomscroll in an attempt to cope. The AIs, deducing he is a centrist, begin recommending him radical centrist views to keep him engaged, which quickly devolve into propaganda and conspiracy theories by the anti-democratic "Extreme Center" movement, radicalizing Ben and affecting his daily life to the point of near-isolation. Ultimately, Ben attends an Extreme Center rally that devolves into violence when similarly-radicalized counter-protestors arrive. Cassandra learns Ben is there and searches for him, but both are detained by riot police. At the end of the narrative, the AIs merge into one entity while Ben's avatar becomes a human representation of himself, and they stare at each other.
Cast
Interviewees
Tristan Harris, former Google design ethicist, co-founder and CEO of Apture (2007), and co-founder of the Center for Humane Technology; co-host of the podcast Your Undivided Attention with Aza Raskin
Tim Kendall, former director of monetization at Facebook, former president of Pinterest, and CEO of Moment (a mobile application that tracks screen time)
Jaron Lanier, computer philosophy writer, computer scientist, visual artist, and composer of contemporary classical music; author of Ten Arguments for Deleting Your Social Media Accounts Right Now (2018)
Roger McNamee, early investor at Facebook, author of Zucked: Waking Up to the Facebook Catastrophe (2019), and cofounder of the venture capital firm Elevation Partners
Aza Raskin, former head of user experience at Mozilla Labs and creative lead for Firefox; co-founder of the Center for Humane Technology and founder of Massive Health; inventor of the infinite scroll
Justin Rosenstein, former Facebook engineering manager, former Google product manager, and co-founder of Asana and One Project
Shoshana Zuboff, Professor Emeritus at the Harvard Business School, author of The Age of Surveillance Capitalism (2019)
Jeff Seibert, former head of product at Twitter, serial tech entrepreneur, and co-founder of Digits
Anna Lembke, medical director of addiction medicine at Stanford University School of Medicine
Jonathan Haidt, social psychologist at the New York University Stern School of Business, author of The Righteous Mind: Why Good People are Divided by Politics and Religion (2012) and coauthor of The Coddling of the American Mind: How Good Intentions and Bad Ideas Are Setting Up a Generation for Failure (2018)
Sandy Parakilas, former platform operations manager at Facebook and former product manager at Uber
Cathy O'Neil, data scientist and author of Weapons of Math Destruction (2016)
Randima Fernando, former product manager at Nvidia, former executive director at Mindful Schools, and co-founder and executive director of the Center for Humane Technology
Joe Toscano, former experience design consultant at Google and author of Automating Humanity (2018)
Bailey Richardson, early team member of Instagram and partner at People & Company
Rashida Richardson, assistant professor of law and political science at Northeastern University School of Law and former director of policy research at AI Now Institute
Guillaume Chaslot, former software engineer at Google (YouTube) and founder of AlgoTransparency
Renée DiResta, technical research manager at the Stanford Internet Observatory and former head of policy at Data for Democracy
Cynthia M. Wong, former senior internet researcher at Human Rights Watch
Alex Roetter, former senior vice president of engineering at Twitter
Lynn Fox, former director of corporate PR and Mac PR at Apple, former executive of corporate communications at Google
Actors
Skyler Gisondo as Ben
Kara Hayward as Cassandra
Sophia Hammons as Isla
Chris Grundy as Stepdad
Barbara Gehring as Mother
Vincent Kartheiser as Artificial Intelligence
Catalina Garayoa as Rebecca
Sergio Villarreal as Luiz
Laura Obiols as Vendetta
Vic Alejandro as Police officer
Narrative casting was led by Jenny Jue.
Themes
The Social Dilemma centers on the social and cultural impact of social media usage on regular users, with a focus on algorithmically enabled forms of behavior modification and psychological manipulation. The film depicts an array of related themes, including technological addiction, fake news, depression, and anxiety.
One interviewee, Tim Kendall, a former director of Facebook, spoke up on the alarming goal of the company: updating the app with increased addictiveness for a consistent boost in engagement. Another interviewee, Tristan Harris, former Google designer, compares the addiction level to a "Vegas slot machine" as users "check their phones hoping that they have a notification, as it's like they are pulling the lever of a slot machine hoping they hit the jackpot".
Misinformation and fake news are commonly spread on social media, and users are unable to distinguish between fake and real news, resulting in differences in ideology and societal division. The immersion of users in this app, who are thus exposed to limitless information, according to Kendall, could potentially lead to tension within society.
The Social Dilemma also discusses how social media can cause depression and give users anxiety. Jonathan Haidt, a social psychologist and author, highlights the influence of social media on depression and anxiety, especially in younger adolescents. The documentary reports statistics on depression, self-harm, and suicide leading to hospitalization, specifically in American teen girls, resulting from social media use. The number of hospitalizations remained stable until around 2011 and rose a significant 62 percent in older teen girls (ages 15–19) and up 189 percent in younger teen girls (ages 10–14) since 2009 in the US. The same pattern is shown in the rates of suicide, which had increased 70 percent in older teen girls and 151 percent in younger teen girls compared to 2001–2010. According to Haidt's interview, people born after 1996 have grown up in a society where social media usage is the norm, thus resulting in consistent exposure to overwhelming content from a young age.
Production
Inspiration
Jeff Orlowski, who is mostly known for his work in Chasing Coral and Chasing Ice, began production on The Social Dilemma in 2018 and concluded it in 2019. When asked where his inspiration came from during the film's panel at Deadline Hollywoods Contenders Documentary event, Orlowski said that he has "always been curious about big systemic and societal challenges". He came to believe that "invisibly, a handful of designers in Silicon Valley are writing code that is shaping the lives of billions of people around the planet".
Orlowski, on the film's FAQ page, states:
The film's graphics, animation, and visual effects were made by Mass FX Media and produced by Netflix.
Soundtrack
The film's music is composed by Mark Crawford, "a Primetime Emmy-nominated composer and filmmaker" who was nominated for an ASCAP Award for his work on The Social Dilemma. With the use of "human-produced" and mechanical sounds, as Crawford explained in The Social Dilemma interview, he displayed the alarming impacts of social media through this soundtrack.
Release
The Social Dilemma premiered at the 2020 Sundance Film Festival on January 26, 2020, and was released worldwide on Netflix on September 9, 2020. The documentary went on to be viewed in 38,000,000 homes within the first 28 days of release. It won two awards out of seven nominations at the 73rd Primetime Creative Arts Emmy Awards in 2021.
The film is approximately 94 minutes long and can only be accessed on Netflix. However, a free 40-minute version can be viewed by requesting it through the film's official webpage.
Reception
Critical response
The Social Dilemma received generally positive reviews. On the review aggregator website Rotten Tomatoes, the film holds an approval rating of , based on reviews, with an average rating of . The website's critics consensus reads, "Clear-eyed and comprehensive, The Social Dilemma presents a sobering analysis of our data-mined present." On Metacritic, the film has a weighted average score of 78 out of 100, based on nine critics, indicating "generally favorable reviews".
Devika Girish from The New York Times gave the film a positive review, stating it was "remarkably effective in sounding the alarm about the incursion of data mining and manipulative technology into our social lives and beyond". Mark Kennedy of ABC News called the film "an eye-opening look into the way social media is designed to create addiction and manipulate our behaviour, told by some of the very people who supervised the systems at places like Facebook, Google, and Twitter". Nell Minow of RogerEbert.com noted that the film "asks fundamental and existential questions" of humanity's potential self-destruction through its own use of computer technology, and praised its "exceptional" use of confessions from leaders and key players in the social media industry.
Elizabeth Pankova of The New Republic noted "none of the information in the film is particularly new" but argued what made The Social Dilemma effective was "the purveyors of this information: the remorseful, self-aware warriors turned conscientious objectors of Silicon Valley". Pranav Malhotra of Slate stated the film "plays up well-worn dystopian narratives surrounding technology" and "depend[s] on tired (and not helpful) tropes about technology as the sole cause of harm, especially to children", while also failing to acknowledge activists and commentators who have long criticized social media, citing scholars such as Safiya Noble, Sarah T. Roberts, and Siva Vaidhyanathan. In an analysis of the film's persuasive techniques, Laura Alvarez Trigo of PopMecC stated, "The Social Dilemma manages to construct a Manichean narrative with a very elusive and misconstrued evil side" but pointed to the film's own resemblance to the propaganda and manipulation it criticizes, stating the film could have benefited from "providing the audience with the necessary tools to engage with the platforms that they use in a more critical way" and "a nuanced explanation of the present ethical problems [to] help people benefit from new technologies without having to completely shut them down or ban them for their teenage children".
Notable criticism was directed toward the fictional narrative surrounding the family and the AIs. Casey Newton at The Verge pointed to certain directorial decisions, such as "the ominous piano score that persuades every scene" as giving it "the feeling of camp". Nell Minow stated that "even the wonderfully talented Skyler Gisondo cannot make a sequence work where he plays a teenager seduced by extremist disinformation, and the scenes with Vincent Kartheiser embodying the formulas that fight our efforts to pay attention to anything outside of the online world are just silly." Pranav Malhotra called the narratives an "uncritical" presentation of a dystopia lacking nuance. In a rare defense of the film's oft-denounced dramatizations, John Naughton of The Guardian commented on the narrative's focus, stating that "the fictional strand is necessary because the biggest difficulty facing critics of an industry that treats users as lab rats is that of explaining to the rats what's happening to them while they are continually diverted by the treats (in this case dopamine highs) being delivered by the smartphones that the experimenters control."
Industry response
Facebook released a statement on its About page, stating that the film "gives a distorted view of how social media platforms work to create a convenient scapegoat for what are difficult and complex societal problems".
CNBC reported that social media users were doubting if they should continue using Facebook or Instagram after watching The Social Dilemma. However, when asked about the possibility of a decline in its users, Facebook refused to answer or give any comment on the subject.
Mozilla employees Ashley Boyd and Audrey Hingle noted that while the "making, release and popularity of The Social Dilemma represents a major milestone towards [the goal of] building a movement of internet users who understand social media's impact and who demand better from platforms", the film would have benefited from featuring more diverse voices.
Accolades
See also
Algorithmic radicalization
Body dysmorphic disorder
Communal reinforcement
Cyberpsychology
Digital citizen
Digital media use and mental health
Doomscrolling
Facebook–Cambridge Analytica data scandal
False consensus effect
Filter bubble
Group polarization
Persuasive technology
Search engine manipulation effect
Selective exposure theory
Social dilemma
Social media and psychology
Surveillance capitalism
Targeted advertising
References
Further reading
The Social Network
The Internet's Own Boy
The Great Hack
External links
2020 films
2020 documentary films
Primetime Emmy Award–winning broadcasts
American documentary films
Facebook criticisms and controversies
Documentary films about the Internet
Films about social media
Criticisms of software and websites
Netflix original documentary films
2020s English-language films
2020s American films
Television Academy Honors winners
English-language documentary films | The Social Dilemma | [
"Technology"
] | 3,462 | [
"Criticisms of software and websites"
] |
65,267,104 | https://en.wikipedia.org/wiki/Spirit%20Island%20%28board%20game%29 | Spirit Island is a euro-style co-operative strategy board game designed by R. Eric Reuss and published by Greater Than Games in 2017. Digital versions have been released for PC, iOS, and Android.
In the game, players take the role of spirits on an island and win by driving off colonizing invaders.
History
Reuss designed Spirit Island in response to other board games in which players take the role of colonizers. The Invader game pieces were made white deliberately in Spirit Island to highlight that light colors do not always imply 'good'.
The game has four expansions, Branch & Claw, Jagged Earth, Feather and Flame, and Nature Incarnate (the last released in 2023). Both the base game and several expansions were funded via Kickstarter, while Nature Incarnate was funded via BackerKit. A multi-platform digital version of the game, first announced in 2018, was released in 2020. The game was also released on iOS and Android devices. The mobile versions have a "free to learn" version, which costs no money and enables access to a tutorial game with four spirits available to play. A new version of the game, titled Horizons of Spirit Island was released in 2022. While Horizons contains the same mechanics as the full game, it contains fewer, simpler, game pieces which are cheaper to produce. Additionally, the spirits included with Horizons are intended to be easier for new players to learn.
Gameplay
In Spirit Island, players take the role of Spirits on an island. They must drive off the colonizing Invaders, who grow their presence on the island, including founding Towns and Cities, over the course of a game. The core game can be played by 1–4 players, and the Jagged Earth expansion adds support for up to 6 players. Over the course of the game players unlock more abilities for their Spirit and additional Power cards, making them stronger and more capable of pushing back the Invaders. The Invaders' actions are controlled by a deck of cards that dictates the areas of the board they Explore, Build, and "Ravage". Any tiles that the players aren't able to protect against the "Ravage" action results in a Blight token being added to it.
To win the game, players must use their Spirit's powers to clear out the Invaders and their settlements, while also generating Fear, which lowers the criteria to win. The players lose if the Invaders add too many Blight tokens to the board, if one of the Spirits has all its Presence removed from the board, or if the deck of Invader actions runs out.
The game contains an array of Spirits – eight in the base game, two in the Branch & Claw expansion, 10 in the Jagged Earth expansion, and two "Promo Packs" with two additional Spirits in each (The content from both "Promo Packs" was released in 2022 as the third expansion Feather and Flame) – for players to choose from. Players can select any combination of Spirits, and each has unique abilities and ways of being played.
Reception
Ars Technica included the game in their list of best board games of 2017. In their full review they described the game as complex and deep, calling the array of choices a "wonderfully thinky puzzle", though highlighting the potential for analysis paralysis. They praised the progression of the spirits' abilities over the game, and concluded that it was an "easy recommendation". Kotaku commented positively on the game's complexity and ability to build tension, but found the game was hard to start, requiring patience to fully understand.
In their list of best fantasy board games in 2020, CNET named Spirit Island the best complex cooperative game of the year, and PC Gamer lists it in their best cooperative board games. In an article for The Atlantic, Luke Wilkie stated that Spirit Island is "one of the few flat-out anti-colonial games on the market".
From March to June 2022, the game was ranked as high as number 9 on BoardGameGeek's list of highest-rated games. , it ranks at number 11.
References
External links
Asymmetric board games
Cooperative board games
Board games introduced in 2017
Kickstarter-funded tabletop games
Political tabletop games
Social justice board games | Spirit Island (board game) | [
"Physics"
] | 868 | [
"Asymmetric board games",
"Symmetry",
"Asymmetry"
] |
65,267,385 | https://en.wikipedia.org/wiki/Rectangle%20packing | Rectangle packing is a packing problem where the objective is to determine whether a given set of small rectangles can be placed inside a given large polygon, such that no two small rectangles overlap. Several variants of this problem have been studied.
Packing identical rectangles in a rectangle
In this variant, there are multiple instances of a single rectangle of size (l,w), and a bigger rectangle of size (L,W). The goal is to pack as many small rectangles as possible into the big rectangle without overlap between any rectangles (small or large). Common constraints of the problem include limiting small rectangle rotation to 90° multiples and requiring that each small rectangle is orthogonal to the large rectangle.
This problem has some applications such as loading of boxes on pallets and, specifically, woodpulp stowage. As an example result: it is possible to pack 147 small rectangles of size (137,95) in a big rectangle of size (1600,1230).
Packing identical squares in a rectilinear polygon
Given a rectilinear polygon (whose sides meet at right angles) R in the plane, a set S of points in R, and a set of identical squares, the goal is to find the largest number of non-overlapping squares that can be packed in points of S.
Suppose that, for each point p in S, we put a square centered at p. Let GS be the intersection graph of these squares. A square-packing is equivalent to an independent set in GS. Finding a largest square-packing is NP-hard; one may prove this by reducing from 3SAT.
Packing different rectangles in a given rectangle
In this variant, the small rectangles can have varying lengths and widths, and they should be packed in a given large rectangle. The decision problem of whether such a packing exists is NP-hard. This can be proved by a reduction from 3-partition. Given an instance of 3-partition with 3m positive integers: a1, ..., a3m, with a total sum of m T, we construct 3m small rectangles, all with a width of 1, such that the length of rectangle i is ai + m. The big rectangle has width m and length T + 3m. Every solution to the 3-partition instance induces a packing of the rectangles into m subsets such that the total length in each subset is exactly T, so they exactly fit into the big rectangle. Conversely, in any packing of the big rectangle, there must be no "holes", so the rectangles must not be rotated. Therefore, the packing must involve exactly m rows where each row contains rectangles with a total length of exactly T. This corresponds to a solution of the 3-partition instance.
When there is an additional restriction that the packing must be exact (with no wasted space), the small rectangles may be rotated only by multiples of 90°. In this case, the problem is in NP. Without this requirement, the small rectangles may be rotated in arbitrary angles. In this more general case, it is not clear if the problem is in NP, since it is much harder to verify a solution.
Packing different rectangles in a minimum-area rectangle
In this variant, the small rectangles can have varying lengths and widths, and their orientation is fixed (they cannot be rotated). The goal is to pack them in an enclosing rectangle of minimum area, with no boundaries on the enclosing rectangle's width or height. This problem has an important application in combining images into a single larger image. A web page that loads a single larger image often renders faster in the browser than the same page loading multiple small images, due to the overhead involved in requesting each image from the web server. The problem is NP-complete in general, but there are fast algorithms for solving small instances.
Related problems
Guillotine cutting is a variant of rectangle packing, with the additional constraint that the rectangles in the packing should be separable using only guillotine cuts.
Maximum disjoint set (or Maximum independent set) is a problem in which both the sizes and the locations of the input rectangles are fixed, and the goal is to select a largest sum of non-overlapping rectangles. In contrast, in rectangle packing (as in real-life packing problems) the sizes of the rectangles are given, but their locations are flexible. Some papers use the term "packing" even when the locations are fixed.
Circle packing in a rectangle
Square packing in a square
De Bruijn's theorem: packing congruent rectangular bricks of any dimension into rectangular boxes.
References
Packing problems
Geometric algorithms
NP-hard problems | Rectangle packing | [
"Mathematics"
] | 1,005 | [
"NP-hard problems",
"Mathematical problems",
"Packing problems",
"Computational problems"
] |
65,269,068 | https://en.wikipedia.org/wiki/Shallow%20%28underwater%20relief%29 | Shallow is an elevation of the bottom in the sea, river, lake, which impedes navigation. It is a type of an underwater relief where the depth of the water is low compared to that of the surrounding points.
Usually formed by sand or pebble deposits, can also be of volcanic origin or the result of human or animal activities.
Stranded near the shore of a reservoir or watercourse is called a shoal; the shallow ocean area adjacent to the mainland is the continental shelf.
Shallows can be permanently hidden under water or appear on the surface of the water periodically (for example, during low tide in the seas, changes in the water level in rivers from water content) in the form of islands, sediments, side streams, spits, etc.
On river shoals, if possible, to cross the river on foot, or by land transport, arrange fords.
See also
Spit (landform)
Rapids
Reef
Ocean bank
Bibliography
Jean-Jacques Delannoy, Philip Deline, René Lhénaff, Géographie physique: aspects et dynamique du géosystème terrestre, De Boeck Superieur, 2016, p. 634.
Republished in 2001 then in 2014 under the title Dictionnaire de la mer: savoir-faire, traditions, vocabulaires-techniques, Omnibus, XXIV-861 p.,
Hydrology | Shallow (underwater relief) | [
"Chemistry",
"Engineering",
"Environmental_science"
] | 289 | [
"Hydrology",
"Hydrology stubs",
"Environmental engineering"
] |
65,269,801 | https://en.wikipedia.org/wiki/Soul%20Electronics | Soul Electronics (stylized as SOUL Electronics or simply SOUL) is an audio equipment company. Founded in 2010, it produces various lines of wireless, Bluetooth-enabled headphones, earbuds, and speakers.
History
Soul Electronics was founded in 2010. The entity was originally known as Signeo USA, an American subsidiary of the Hong Kong-based Signeo Design International. In January 2011 at that year's Consumer Electronics Show (CES), the company introduced SOUL by Ludacris, a line of headphones designed in collaboration with the rapper, Ludacris. The line featured five different pairs of headphones, which were released to the public later in 2011. By that time, the company had become known as Soul Electronics.
In 2012, Soul Electronics partnered with sprinter, Usain Bolt, on the design of a new line of headphones and earbuds designed to be used while running or exercising. In the following two years, the company entered into a number of other sponsored partnerships with athletes, including Brendan Schaub, Tim Tebow, and Alex Fowler. In 2015, the company introduced the Combat+ Sync headphones which came with a built-in walkie-talkie feature. At CES 2018, the company introduced a new artificial intelligence feature in its "Run Free Pro Bio" and "Blade" models that would offer users live, in-ear coaching while running.
In 2019, the company introduced four new products: the Ultra Wireless over-ear headphones, the ST-XX wireless earbuds, the ST-XS2 wireless earphones, and the S-Storm portable Bluetooth speaker. Four additional earbud and earphone lines were released in 2020, including SYNC Pro, the SYNC ANC (active noise-canceling), S-Fit, and S-Gear.
In 2023, the company introduced their first open-ear style headphones called the Openear Series which include Openear 2, Openear Plus, Openear S-Clip and Openear S-Free.
Products
Soul Electronics produces a number of audio products, generally targeted at runners and other consumers who exercise. Its current products include the Ultra Wireless over-ear headphones, the S-Storm portable speaker, and a number of earbud and earphone lines. The company's higher-end earbuds include the SYNC Pro and SYNC ANC. Both of these options come with dual microphones, touch features, and longer battery life than other Soul models. The latter also features active-noise canceling. Its mid-range earbuds include the ST-XX and ST-XS2 which are water-resistant and have touch features. Lower-end models include the S-Fit and S-Gear, which are water-resistant and marketed as an affordable option for runners. All Soul products are Bluetooth compatible.
References
External links
Official website
Audio electronics
Chinese companies established in 2010
2010 establishments in Hong Kong | Soul Electronics | [
"Engineering"
] | 599 | [
"Audio electronics",
"Audio engineering"
] |
65,269,875 | https://en.wikipedia.org/wiki/Galactogen | Galactogen is a polysaccharide of galactose that functions as energy storage in pulmonate snails and some Caenogastropoda. This polysaccharide is exclusive of the reproduction and is only found in the albumen gland from the female snail reproductive system and in the perivitelline fluid of eggs.
Galactogen serves as an energy reserve for developing embryos and hatchlings, which is later replaced by glycogen in juveniles and adults. The advantage of accumulating galactogen instead of glycogen in eggs remains unclear, although some hypotheses have been proposed (see below).
Occurrence and distribution
Galactogen has been reported in the albumen gland of pulmonate snails such as Helix pomatia, Limnaea stagnalis, Oxychilus cellarius, Achatina fulica, Aplexa nitens and Otala lactea, Bulimnaea megasoma, Ariolimax columbianis, Ariophanta, Biomphalaria glabrata, and Strophochelius oblongus. This polysaccharide was also identified in the Caenogastropoda Pila virens and Viviparus, Pomacea canaliculata, and Pomacea maculata.
In adult gastropods, galactogen is confined to the albumen gland, showing a large variation in content during the year and reaching a higher peak in the reproductive season. During the reproductive season, this polysaccharide is rapidly restored in the albumen gland after being transferred to the eggs, decreasing its total amount only after repeated ovipositions. In Pomacea canaliculata snails, galactogen would act, together with perivitellins, as a main limiting factor of reproduction. This polysaccharide has been identified in the Golgi zone of the secretory cells from the albumen gland in the form of discrete granules 200 Å in diameter. The appearance of galactogen granules within the secretory globules suggests that this is the site of biosynthesis of the polysaccharide.
Apart from the albumen gland, galactogen is also found as a major component of the perivitelline fluid from the snail eggs, comprising the main energy source for the developing embryo.
Structure
Galactogen is a polymer of galactose with species-specific structural variations. In this polysaccharide, the D-galactose are predominantly β (1→3) and β (1→6) linked; however some species also have β (1→2) and β (1→4). The galactogen of the aquatic Basommatophora (e.g. Lymnaea, Biomphalaria) is highly branched with only 5-8 % of the sugar residues in linear sections, and β(1→3) and β(1→6) bonds alternate more-or-Iess regularly. In the terrestrial Stylommatophora (e.g. Helix, Arianta, Cepaea, Achatina) up to 20% of the sugar residues are linear β(1→3) bound. The galactogen of Ampullarius sp species has an unusually large proportion of linearly arranged sugars, with 5% β(1→3), 26% β(1→6), and 10% β(1→2). Other analyses in Helix pomatia suggested a dichotomous structure, where each galactopyranose unit bears a branch or side chain.
Molecular weight determinations in galactogen extracted from the eggs of Helix pomatia and Limnaea stagnalis were estimated in 4x106 and 2.2x106, respectively. In these snails galactogen contains only D-galactose. Depending upon the origin of the galactogen, apart from D-galactose, L-galactose, L-fucose, D-glucose, L-glucose and phosphate residues may also be present; for instance, the galactogen from Ampullarius sp. contains 98% of D-galacotose and 2% of L- fucose, and the one isolated from Pomacea maculata eggs consist in 68% of D-galactose and 32% of D-glucose. Phosphate-substituted galactose residues are found in the galactogen of individual species from various snail genera such as Biomphalaria, Helix and Cepaea. Therefore, current knowledge indicates it could be considered either a homopolysaccharide of or a heteropolysaccharide dominated by galactose.
Metabolism
Galactogen is synthesized by secretory cells in the albumen gland of adult female snails and later transferred to the egg. This process is under neurohormonal control, notably by the brain galactogenin. The biochemical pathways for glycogen and galactogen synthesis are closely related. Both use glucose as a common precursor and its conversion to activated galactose is catalyzed by UDP-glucose 4-epimerase and galactose-1-P uridyl-transferase. This enables glucose to be the common precursor for both glycogenesis and galactogenesis. In fact, both polysaccharides are found in the same secretory cells of the albumen gland and are subject to independent seasonal variations. Glycogen accumulates in autumn as a general energy storage for hibernation, whereas galactogen is synthesized during spring in preparation of egg-laying. It is commonly accepted that galactogen production is restricted to embryo nutrition and therefore is mainly transferred to eggs.
Little is known about the galactogen-synthesizing enzymes. A D-galactosyltransferase was described in the albumen gland of Helix pomatia. This enzyme catalyzes the transfer of D-galactose to a (1→6) linkage and is dependent upon the presence of acceptor galactogen. Similarly, a β-(1→3)-galactosyltransferase activity has been detected in albumen gland extracts from Limnaea stagnalis.
In embryos and fasting newly hatched snails, galactogen is most likely an important donor (via galactose) of metabolic intermediates. In feeding snails, the primary diet is glucose-containing starch and cellulose. These polymers are digested and contribute glucose to the pathways of intermediary metabolism. Galactogen consumption begins at the gastrula stage and continues throughout development. Up to 46-78 % of egg galactogen disappears during embryo development. The remainder is used up within the first days after hatching.
Only snail embryos and hatchlings are able to degrade galactogen, whereas other animals and even adult snails do not. β-galactosidase may be important in the release of galactose from galactogen; however, most of the catabolic pathway of this polysaccharide is still unknown.
Other functions
Besides being a source of energy, few other functions have been described for galactogen in the snail eggs, and all of them are related to embryo defense and protection. Given that carbohydrates retain water, the high amount of this polysaccharide would protect the eggs from desiccation from those snails that have aerial oviposition. Besides, the high viscosity that the polysaccharide may confer to the perivitelline fluid has been suggested as a potential antimicrobial defense.
Since galactogen is a β-linked polysaccharide, such as cellulose or hemicelluloses, specific biochemical adaptations are needed to exploit it as a nutrient, such as specific glycosidases. However, apart from snail embryos and hatchlings, no animal seems to be able to catabolize galactogen, including adult snails. This fact led to consider galactogen as part of an antipredation defense system exclusive of gastropods, deterring predators by lowering the nutritional value of eggs.
References
Polysaccharides
Carbohydrates | Galactogen | [
"Chemistry"
] | 1,717 | [
"Biomolecules by chemical classification",
"Carbohydrates",
"Organic compounds",
"Carbohydrate chemistry",
"Polysaccharides"
] |
65,269,925 | https://en.wikipedia.org/wiki/Dapansutrile | Dapansutrile (OLT1177) is an inhibitor of the NLRP3 (nucleotide-binding domain leucine-rich repeat and pyrin domain containing receptor 3) inflammasome.
An inflammasome can be defined as an immune system receptor that induces inflammation through the activation of caspase 1 and caspase 11 when it is triggered by damaged cells, microbial pathogens, and stress. NLRP3 is a canonical inflammasome. The NLRP3 inflammasome comprises NLRP3, the apoptosis spec-like protein (ASC) and the caspase-1 (Figure 1). The NLRP3 inflammasome forms by binding to pattern recognition receptors (PRRs) and damage associated molecular patterns (DAMPS) that activate caspase 1 which then signals for the secretion of pro-inflammatory cytokines IL-1β and IL-18 resulting in pyroptosis Constant activation of the NLRP3 inflammasome is believed to play a direct or indirect role in acute arthritis, atherosclerosis and various neurodegenerative diseases such as multiple sclerosis (MS), Alzheimer's disease (AD), and Parkinson's disease (PD),,. This drug was developed by Olactec Therapeutics with the purpose of decreasing IL-1β peripheral inflammation by binding to the NLRP3 protein and inhibiting the formation of the NLRP3 inflammasome. Interestingly, dapansutrile has also been found to reduce levels of pro inflammatory cytokines IL-18 without interfering with TNF-α levels. Stressed cells in the system can ignite the NLRP3 inflammasome which in turn produces the secretion inflammatory cytokines such as IL-1β and IL-18. Dapansutrile has tested in clinical trials and has been proposed as a beneficial compound for the remedy of osteoarthritis, and gouty arthritis. Nevertheless, other preclinical research has proposed dapansutrile to be potentially beneficial for heart failure and multiple sclerosis.
Molecular Structure and Properties
Dapansutrile is a β-sulfonyl nitrile compound with four carbon, seven hydrogen, one nitrogen, two oxygen, and one sulfur atom (Figure 2). The molecular formula of this compound is C4H7NO2S, and it carries a molecular weight of 133.7 g/mol. Compound acknowledged by the names of dapansutrile, OLT1177, and 3-(methylsulfonyl)propanenitrile.
Synthesis
OLT1177 is synthesized by alkylation of sodium methanesulfinate with 3-bromopropionitrile. This reaction produces crude methylsulfonylpropionitrile which is then purified through dissolution into acetone, filtration of the sodium bromide bi-product, solvent exchange via distillation, and recrystallization from ethanol.
Dapansutrile's Mechanism of Action
Dapansutrile's Reaction Pathways
Dapansutrile denoted as a β-sulfonyl nitrile molecule. Its mechanism of action induces a Pinner reaction which is initiated by reacting with thiols, alcohols and amines. Thus, leading to the formation of thiomidates, imidates and amidines respectively. The nitrile group of OLT1177 is still not denoted as a covalent, noncovalent, irreversible or non-reversible inhibitor as there are currently no studies about its reactivity. Nevertheless, some researchers believe that dapansutrile promotes inhibition of NLRP3 through covalent bonds (Figure 4).
Summary Biological Effects of Dapansutrile
Pharmacokinetics
Selectivity
Dapansutrile targets the inhibition of the NLRP3 ATPase and thus blocks the activation of the inflammasome's ASC, and caspase-1 interaction; thereby preventing the assembly of the inflammasome and inflammatory signals such as IL-1β and IL-18. This drug also inhibits pyroptosis. Nevertheless, the drug does not impact the mRNA levels of the NLRP3, ASC, caspase-1, IL-1β, and IL-18 genes.
Research of dapansutrile presents that the compound solely inhibits the NLRP3 inflammasome. Murine macrophages were used and stimulated with lipopolysaccharides and either flagellin or the dsDNA analog Poly(dA:dT) to activate inflammasomes such as NLRC4 and AIM 2 respectively. When Dapansutrile was added they found no difference in the release of TNF-α and IL-1β cytokines to when these inflammasomes were activated.
Other Drug Targets
Other known targets of dapansutrile include several phosphorylated kinases such as Src; Fyn; HcK; STAT3. Human monocyte derived macrophages (HMDM) cells were stimulated with lipopolysaccharide, and nigericin. Dapansutrile was then added and they found a 26%, 35%, 43% and 33% reduction of these phosphorylated kinases respectively.
Dosages
In vitro: Human derived macrophages were cultured to study the effect of dapansutrile cytokine production. It was found that dapansutrile at a 1 μM dose inhibited secretion of IL-1β by 60%, and IL-18 levels by 70%. The drug was also found to selectively inhibit pyroptosis at 10 μM.
In vivo: A phase one clinical trial of 35 subjects was conducted to establish the safety of dapansutrile. The daily mean plasma concentration maximum (Cmax) for a single oral dose of dapansutrile was 2,700 ng/mL for the 100-mg dose, 9,800 ng/mL for the 300 mg dose and 32,00 ng/mL for the 1,000 mg dose (Figure 5). Dapansutrile was also studied if given repeatedly once per day for 8 days with a dose of either 100 mg, and 300 mg, or 1,000 mg. The subjects mean plasma concentration on day 8 were 4,800 ng/mL for the 100 mg dose, 15,800 ng/mL for the 300 mg dose and 41,400 ng/mL for the 1,000 mg dose.
Pharmacodynamics
Safety and Efficacy of Dapansutrile
In the Marchetti et al. study, seven of the 35 subjects reported adverse events. Five of the cases were in the single dose study while two cases were in the multi-regimen group. However, the adverse effects were considered unrelated to dapansutrile. Subjects presented no changes in blood pressure (systolic and diastolic), urinalysis, heart rate, liver function enzymes or acute phase proteins in the cohort after an 8-day trial with up to daily 1,000 mg dosing of dapansutrile.
Potential Therapeutic Applications
Neurodegenerative diseases
Multiple Sclerosis:
Multiple sclerosis (MS) is a neurodegenerative disease characterized by the immune system deteriorating myelin. Myelin damage leads to the disruption of neuronal signaling, and dysregulated inflammatory levels. Dapansutrile was used in the Experimental Autoimmune Encephalomyelitis (EAE) mouse model to understand its possible underlying effects for MS. It was found that mice fed with the dapansutrile diet protected the mice from demyelination in the spinal cord as well as decreased their levels of interleukins IL-1β and IL-18. Currently, it is unclear whether the drug could inhibit microglial reactivity, but currently it has no known benefits to aid in the prevention of dementia and cognitive function.
Inflammation
Gouty Arthritis:
Gouty arthritis is an inflammatory joint disorder, partly induced to the activation of the NLRP3 inflammasome and excess IL-1β activation which leads to gout attacks. This is due to excess uric acid in the blood which promotes the formation of uric acid crystals in the joints. Uric acid is a known danger signal and induce the cleavage signal of the caspase-1 NLRP3 inflammasome.
Animal Model Experiments: In 2018, two murine models were used to validate Dapansutrile as a drug beneficial for acute joint inflammation. They injected zymosan or monosodium urate crystals in order to induce gouty arthritis in mice. OLT1177 was then either injected intraperitoneally or through their diet. In essence, the drug reduced joint inflammation, as well as interleukin levels demonstrating its therapeutic benefit for this disease.
Clinical Trials: As for clinical trials, Olatec Therapeutics also conducted a phase 2.a trials where Dapansutrile was given to 29 subjects with gouty arthritis.
Cardiovascular Diseases
Acute Myocardial Infarction/ Heart Attack:
One of the major downstream effects of having coronary artery disease is possibility of having an acute myocardial infarction or heart attack. In mouse models, Dapansutrile was found to decrease infarct size a dose-dependent manner.
Heart Failure:
Olatec Therapeutics conducted a phase 1 clinical trial for Dapansutrile as a potential therapeutic for systolic heart failure. They have carried out a Phase 1 double blinded study with a total of 30 subjects to assess the drug's safety and pharmacodynamics. The drug was given in capsule form and the subjects were divided into 3 cohorts. Each cohort had 8 subjects taking an oral capsule with 100 mg Dapansutrile while 2 subjects were given the placebo capsule. Although the completion date of this clinical trial was on November 21, 2019, the results of the study have not yet been published.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) / COVID-19:
Dapansutrile has been proposed by a number of scientists as a measure to reduce cardiovascular outcomes that seem to be brought on by COVID-19. The rationale behind using Dapansutrile is to inhibit the NLRP3 inflammasome and reduce the chances of a cytokine storm which seems to cause multi-organ failure in COVID-19 patients. Subjects with COVID-19 have shown to have an increased concentration of pro-inflammatory cytokines resulting in the cytokine storm, and thus producing an exhaustion of lymphocytes. NLRP3 not only activates cytokines but other key players that can inflict myocardial damages, and Acute Respiratory Distress Syndrome (ARDS), and its inhibition has been found to deter these outcomes. Thus, dapansutrile is proposed as a possible mediator to relief and prevent COVID-19 symptoms and effects.
References
Sulfonyl groups
Nitriles
Anti-inflammatory agents | Dapansutrile | [
"Chemistry"
] | 2,357 | [
"Substituents",
"Nitriles",
"Functional groups",
"Sulfonyl groups"
] |
65,269,943 | https://en.wikipedia.org/wiki/Animal%20models%20of%20Parkinson%27s%20disease | Animal models of Parkinson's disease are essential in the research field and widely used to study Parkinson's disease. Parkinson's disease is a neurodegenerative disorder, characterized by the loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc). The loss of the dopamine neurons in the brain, results in motor dysfunction, ultimately causing the four cardinal symptoms of PD: tremor, rigidity, postural instability, and bradykinesia. It is the second most prevalent neurodegenerative disease, following Alzheimer's disease. It is estimated that nearly one million people could be living with PD in the United States.
There are a variety of models that can be utilized to be able to address important aspects of Parkinson's disease. Researchers can consider disease progression, cell death, behavioral characteristics, and more PD phenotypes. Parkinson's disease animal models are divided into two categories: neurotoxin models and genetic models. Neurotoxin models include chemically induced toxicity in the brain; whereas, genetic models include genes that are mutated and induce PD phenotypes.
Neurotoxin models
6-OHDA
6-Hydroxydopamine, better known as 6-OHDA, is a widely used neurotoxin in PD models. It is structurally similar to dopamine, only differentiating by an additional hydroxyl group in the 6-OHDA structure (Figure 1 & Figure 2). Through scientific studies, this neurotoxin has been used in rodents (rats and mice), guinea pigs, cats, dogs, and monkeys. 6-OHDA does not cross the blood-brain-barrier (BBB) making the chemical more selective for dopaminergic neurons. This model requires injecting the 6-OHDA directly into the nigrostriatal pathway, targeting the dopamine transporter (DAT).This can be performed through stereotaxic injections (both unilateral and bilateral are experimentally permissible) and will eventually cause loss of dopamine neurons in the SNpc and loss of dopamine terminals in the striatum since the nigrostriatal pathway is being affected. The neurotoxin can be injected has been shown to be injected into the striatum and the substantia nigra. However, injections into the SNpc is estimated to degrade about 60% of tyrosine hydroxylase (TH+) neurons as well as loss of TH positive terminals in the striatum. A limitation to using 6-OHDA is that the potency of the neurotoxin causes rapid apoptosis, which makes it difficult to study Parkinson's disease progression.
The mechanism of action of 6-OHDA occurs through the aggregation of toxins and the conversion into catecholaminergic neurons. Since the structures of both dopamine and 6-OHDA are similar, the dopamine transporter takes up the 6-OHDA and induces toxicity. This toxicity emerges from the production of free radicals from the additional hydroxyl group in the neurotoxin's structure. There is also oxidative stress occurring mediated through the inhibition of the cell's mitochondrial complex I, producing ROS (reactive oxygen species), which causes a decrease or loss in respiratory activity. In addition, there is also the proposed mechanism of oxidative stress inducing neuroinflammation (Figure 3).
MPTP
1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is a widely used neurotoxin in Parkinson's disease research (Figure 4). In contrast to 6-OHDA, MPTP crosses the BBB which making the neurotoxin even more selective for dopaminergic neurons. Due to the ability to cross the blood-brain-barrier, MPTP is administered peripherally, subcutaneously. This neurotoxin is known to replicate oxidative stress, ROS, energy failure, and inflammation; which are all hallmarks in Parkinson's disease. However, it does not produce Lewy body pathology. The mechanism of action of MPTP is due to its conversion to 1-methyl-4-phenylpyridinium (MPP+) caused by the interaction of MPTP with monoamine oxidase B (MAO-B). (Figure5). MPTP enters astrocytes and is metabolized to MPP+ before being released. Once released into the extracellular space, MPP+ is taken up into the neuron by DAT and is stored in vesicles by the up take of vesicular monoamine transporter (VMAT2). In the neuron, MPP+ inhibits the function of complex 1 of electron transport chain, which decreases ATP production and releases ROS.
Herbicides (rotenone and paraquat)
Rotenone is a chemical compound (Figure 6) that can be derived from the plants: Derris elliptica, D mallaccensis, Lonchocarpus utilis, and L urucu. It is a known neurotoxin that is selective to dopaminergic neurons when administered to rodents via stereotaxic injections. However, it targets the striatum and not the substantia nigra. Moreover, rotenone can cross the BBB and spread through the central nervous system. Since rotenone can cross the blood-brain-barrier, it can be administered peripherally as well. Although, peripheral injections can lead to system toxicity. The exact mechanism of action of rotenone is still unclear, but one aspect that is known is that the herbicide accumulates and clusters in the neuron in organelles like the mitochondria, which disrupts the oxidative phosphorylation mechanism in the cell and inhibits the respiratory chain complex I. Limitations of using rotenone is the lack of reproducibility of results throughout experiments and the quantity of aggregates and lesion. In addition, there is an elevated mortality rate in the animals induced with rotenone.Paraquat
1,1'-dimethyl-4-4'-bipyridinium dichloride (Paraquat) is a nonselective herbicide (Figure 7). Human exposure to this chemical is highly toxic. Its chemical structure is very similar to MPP+, therefore, it was thought to act as a neurotoxin as well. Paraquat has the capability to cross the BBB and is selective to dopamine neurons when injected via stereotaxic injections in the brain. Similar to rotenone, paraquat can also be administered peripherally, however, this can lead to systemic toxicity. It is found to decrease dopamine concentration and produce parkinsonian phenotypes (both physically and behaviorally). Mechanistically, paraquat targets the dopamine transporter to be transported into dopaminergic neurons and ends up in the striatum. It lingers in the midbrain for approximately four weeks. However, since it is capable to cross the BBB, the toxin can be found in other regions such as the pineal gland, cerebral ventricles, olfactory bulb, hypothalamus, and the area postrema. Several studies have demonstrated the relationship between paraquat and oxidative stress indicating that this may be another mechanism of paraquat induced neurodegeneration. In addition, the herbicide is accumulated in the lungs and kidney, resulting high toxicity; as well, as death.
Genetic models
alpha-synuclein
Alpha-synuclein (α-synuclein) is an endogenous protein that is encoded by the SNCA gene and known as the pathological hallmark of Parkinson's disease. It is found in distinct regions of the body, but in PD, alpha-synuclein accumulation in the brain is of main importance. This protein misfolds and accumulates creating insoluble aggregates in the brain known as Lewy bodies (found in the soma) and Lewy neurites (found in the neuropil)(Figure 8). This pathology is well known as synucleinopathies. The inclusions/aggregates lead to dopamine neuronal depletion in the SNpc as well as dopamine terminal loss in the striatum from the projection of SNpc neurons through the nigrostriatal pathway. In addition, studies have shown that there is progressive formation of α-synuclein inclusions in distinct brain areas like the hippocampus, the cortex, and amygdala. However, according to the Braak staging, α-synuclein aggregates initially develop in the olfactory bulb and the lower brainstem; propagating towards the higher brainstem and the substantia nigra; reaching the mesocortex and the thalamus; and, ultimately covering the neocortex. Braak staging is a widely used method to measure the stage of pathology (stage 1 being the lowest level of pathology and stage 4 being the highest) of Parkinson's disease; used both in basic research and clinically.
There are proposed mechanisms by which α-synuclein acts, in terms of pathology, one being the inhibition of the autophagy-lysosome pathway. This pathway is highly important as it is responsible for intracellular degradation. Therefore, as α-synuclein fibrils inhibits the function of autophagy impairing the removal of aggregated protein, there is the production of more α-synuclein inclusions since it cannot be degraded. Other pathological mechanisms include the oxidative stress, dysfunction of the mitochondria, and neuroinflammation.
Alpha-synuclein preformed fibrils
The pre-formed fibril model was developed as a way to study the propagation of α-synuclein. This model consists of injecting extracellular α-synuclein fibrils via stereotaxic injections to induce intracellular α-synuclein aggregation. Consequently, this will induce parkinsonian phenotypes.
The α-synuclein pre-formed fibrils (PFFs) are made in vitro utilizing recombinant α-synuclein monomers which will aggregate and form fibrils. The fibrils can then be manipulated to form different conformations like being sonicated to form short fibrils or form heterogenous mixes of fibrils with oligomers and monomers. Once the fibrils are generated, they can be injected into the brain, where hyperphosphorylation of endogenous α- synuclein (pα-syn) will occur and induce aggregation, forming cytoplasmic Lewy body and Lewy neurite inclusions. This method can be injected in brain regions like the SNpc and the cortex, however, the most common region to inject PFFs is into the striatum. Moreover, the spread of α-synuclein PFFs to brain regions occur through the uptake of the fibrils by dopamine neuron terminals that make their way up to the soma in the SNpc (Figure 9). A limitation to the pre-formed fibril model is that although it is a widely used model, it lacks overt neurodegeneration.
Alpha-synuclein viral vector mediated overexpression
The different synuclein models that have been widely used have also faced challenges of targeting the fibrils to the SNpc, thus, lacking abundant neurodegeneration. Through the viral vector-mediated delivery of alpha-synuclein, the vectors can target the dopaminergic neurons directly. Vectors like lentivirus and adeno-associated virus have been used in this method. This method allows for targeting of nigrostriatal neurons, where α-synuclein protein can be overexpressed and there can be a production of alpha-synuclein- leading to accumulated phosphorylated α-synuclein in the SNpc, and overt dopaminergic neurodegeneration, including loss of dopamine terminals in the striatum. Moreover, the use of the viral vectors, allows for a longer lasting expression of α-synuclein. Delivery of the α-synuclein through the viral vector is conducted through stereotaxic injections into the brain similar to the injections of α-synuclein pre-formed fibrils. In addition, the optimal pα-synuclein expression in this method is around week 4 post-injection.
In contrast to the PFF model, the α-synuclein inclusions are nuclear and demonstrates an anterograde transport in which the pα-syn travels from the soma of the neuron to the terminals, where expression are maintained within medium spiny neurons.
LRRK-2
Leucine-rich repeat kinase (LRRK2) is a protein, that when mutated, is implicated in PD pathology. It is associated with both familial (most prevalent causes of familial PD) and sporadic PD. There are key mutations of the LRRK2 protein, like G2019s which is the most common missense mutation and R1441C/G. Most studies have been conducted on C.elegans, Drosophila, and rodents (mice and rats). It is still unclear as to the mechanism of action of LRRK2, however, the kinase activity is of importance and its ability to function as a GTPase is also a factor in its neurotoxicity. Unlike the other Parkinson's disease genetic models, LRRK2 can exhibit both Lewy body pathology and tau pathology, but it is also unclear as to its relationship. On the other hand, results from LRRK2 mutation studies have demonstrated deficits in dopamine transmission, as well as axonal degeneration. Similar to other genetic animal models, LRRK2 mutations also produce dopaminergic neuron loss in the substantia nigra and Lewy body pathology. LRRK2 knockout models have also been studied and show the increase of protein aggregation and accumulation which also includes α-synuclein; but, it does not decrease degeneration of nigrostriatal neurons. A limitation to the LRRK2 animal model is that although there is a loss in dopaminergic neurons, neurodegeneration is very low.
PINK1
Pten-Induced Kinase 1 (PINK1) mutations are associated with autosomal recessive parkinsonism. It is a neuroprotective kinase predominantly found in the mitochondria and cytoplasmic areas of the cell. PINK1 is also a serine/threonine protein kinase and is associated with the mitochondria. PINK1, in research studies, is generally used as a knockout (KO) model. The mechanism of action of this gene involves the recruitment of the Parkin gene from the cytoplasm to the mitochondria. Once recruited, this leads to augmented ubiquitin activity and therefore induces mitophagy. Mitophagy is a pathway in which the mitochondria is degraded. Both PINK1 and Parkin share functions in the same pathway, therefore, their activities are similar. Some studies have demonstrated expression of the PINK1 mutation in rodents, inducing dopaminergic neuron loss and motor defects. Other studies are more associated with PINK1 KO. PINK1 knockouts show reduction in dopamine levels in the striatum. They express very low levels of dopaminergic neuron loss and do not present the formation of Lewy bodies. However, the KO models demonstrate mitochondria dysfunction and oxidative stress. On the other hand, studies are demonstrating loss of dopaminergic neurons and showing motor deficits in rats.
DJ-1
Protein Deglycase (DJ-1) mutations are associated with recessive forms of familial parkinsonism. It is a molecular chaperone that undergoes reduction-oxidation (redox) reaction and plays a major role in the inhibition of alpha synuclein aggregate formation. It is believed that this is possible due to DJ-1 antioxidant properties, therefore, inhibiting oxidative stress in the cell which is what induces pathological phenotypes. To demonstrate the proposed neuroprotective properties of DJ-1, knockout studies of this gene have shown motor deficits in mice, less dopamine levels in the striatum, and no evidence of Lewy body aggregation. In addition to the knockout model, DJ-1 is very sensitive to neurotoxins (MPTP, 6-OHDA, etc.). Studies have demonstrated that under those conditions, DJ-1 expresses dopaminergic neuron loss in the SNpc and motor defects.
Summary
Table 1 represents a summary of the PD animal models and details regarding their mechanisms of action, pathogenesis, and limitations.
References
Parkinson's disease
Animal models | Animal models of Parkinson's disease | [
"Biology"
] | 3,614 | [
"Model organisms",
"Animal models"
] |
65,270,167 | https://en.wikipedia.org/wiki/Semantics%20%28psychology%29 | Semantics within psychology is the study of how meaning is stored in the mind. Semantic memory is a type of long-term declarative memory that refers to facts or ideas which are not immediately drawn from personal experience. It was first theorized in 1972 by W. Donaldson and Endel Tulving. Tulving employs the word semantic to describe a system of memory that involves “words and verbal symbols, their meanings and referents, the relations between them, and the rules, formulas, or algorithms for influencing them”.
Semantic memory
In psychology, semantic memory is memory for meaning – in other words, the aspect of memory that preserves only the gist, the general significance, of remembered experience – while episodic memory is memory for the ephemeral details – the individual features, or the unique particulars of experience. The term 'episodic memory' was introduced by Tulving and Schacter in the context of 'declarative memory' which involved simple association of factual or objective information concerning its object. Word meaning is measured by the company they keep, i.e. the relationships among words themselves in a semantic network. The memories may be transferred intergenerationally or isolated in one generation due to a cultural disruption. Different generations may have different experiences at similar points in their own time-lines. This may then create a vertically heterogeneous semantic net for certain words in an otherwise homogeneous culture. In a network created by people analyzing their understanding of the word (such as Wordnet) the links and decomposition structures of the network are few in number and kind, and include part of, kind of, and similar links. In automated ontologies the links are computed vectors without explicit meaning. Various automated technologies are being developed to compute the meaning of words: latent semantic indexing and support vector machines as well as natural language processing, artificial neural networks and predicate calculus techniques.
Ideasthesia
Ideasthesia is a psychological phenomenon in which activation of concepts evokes sensory experiences.
The relationship between graphemes and colors, also known as grapheme-color synesthesia, is a typical example of ideasthesia. Here, the alphabet's letters are connected to vibrant color experiences. According to studies, the extracted meaning of a stimulus determines the context-dependent perception of color. For instance, depending on the context in which it is presented, an ambiguous stimulus '5' that can be read as either 'S' or '5' will have the color associated with either 'S' or '5'. If it is provided with other numbers, it will be read as "5" and associated with the respective color. If it is presented between letters, it will be recognized as a "S" and associated with the respective synesthetic color.
Psychosemantics
In the 1960s, psychosemantic studies became popular after Charles E. Osgood's massive cross-cultural studies using his semantic differential (SD) method that used thousands of nouns and adjective bipolar scales. A specific form of the SD, Projective Semantics method uses only most common and neutral nouns that correspond to the 7 groups (factors) of adjective-scales most consistently found in cross-cultural studies (Evaluation, Potency, Activity as found by Osgood, and Reality, Organization, Complexity, Limitation as found in other studies). In this method, seven groups of bipolar adjective scales corresponded to seven types of nouns so the method was thought to have the object-scale symmetry (OSS) between the scales and nouns for evaluation using these scales. For example, the nouns corresponding to the listed 7 factors would be: Beauty, Power, Motion, Life, Work, Chaos, Law. Beauty was expected to be assessed unequivocally as “very good” on adjectives of Evaluation-related scales, Life as “very real” on Reality-related scales, etc. However, deviations in this symmetric and very basic matrix might show underlying biases of two types: scales-related bias and objects-related bias. This OSS design meant to increase the sensitivity of the SD method to any semantic biases in responses of people within the same culture and educational background.
Prototype theory
Another set of concepts related to fuzziness in semantics is based on prototypes. The work of Eleanor Rosch in the 1970s led to a view that natural categories are not characterizable in terms of necessary and sufficient conditions, but are graded (fuzzy at their boundaries) and inconsistent as to the status of their constituent members. One may compare it with Jung's archetype, though the concept of archetype sticks to static concept. Some post-structuralists are against the fixed or static meaning of the words. Derrida, following Nietzsche, talked about slippages in fixed meanings.
Systems of categories are not objectively out there in the world but are rooted in people's experience. These categories evolve as learned concepts of the world – meaning is not an objective truth, but a subjective construct, learned from experience, and language arises out of the "grounding of our conceptual systems in shared embodiment and bodily experience".
A corollary of this is that the conceptual categories (i.e. the lexicon) will not be identical for different cultures, or indeed, for every individual in the same culture. This leads to another debate (see the Sapir–Whorf hypothesis or Eskimo words for snow).
Notes
References
Cognitive psychology
Mental processes | Semantics (psychology) | [
"Biology"
] | 1,104 | [
"Behavioural sciences",
"Behavior",
"Cognitive psychology"
] |
65,270,577 | https://en.wikipedia.org/wiki/Pranav%20Sharma | Pranav Sharma (प्रणव शर्मा) is an astronomer and science historian known for his work on the history of the Indian Space Program. He has curated Space Museum at the B. M. Birla Science Centre (Hyderabad, India). Sharma was in charge of the history of the Indo-French scientific partnership project supported by the Embassy of France in India. He is a national award-winning science communicator and has extensively worked in the popularization of astronomy education in India.
He also served as the Policy and Diplomacy Advisor to United Nations International Computation Centre and Member Secretary (Policy, Transdisciplinary Disruptive Science, and Communications) for G20-Science20.
Sharma is the Co-Lead on the History of Data-Driven Astronomy Project , Adjunct Researcher at Raman Research Institute, Scientific Advisor to Arc Ventures, Science Diplomacy Consultant to Indian National Science Academy, and Visiting Faculty at The Druk Gyalpo's Institute, Bhutan. He is an Associate Member of Astronomical Society of India.
He has co-authored the book Essential Astrophysics: Interstellar Medium to Stellar Remnants, CRC Press, 2019.
References
Astronomy
Social work
Indian scientists
Living people
Year of birth missing (living people) | Pranav Sharma | [
"Astronomy"
] | 253 | [
"nan"
] |
65,273,997 | https://en.wikipedia.org/wiki/Mathematical%20Models%20%28Cundy%20and%20Rollett%29 | Mathematical Models is a book on the construction of physical models of mathematical objects for educational purposes. It was written by Martyn Cundy and A. P. Rollett, and published by the Clarendon Press in 1951, with a second edition in 1961. Tarquin Publications published a third edition in 1981.
The vertex configuration of a uniform polyhedron, a generalization of the Schläfli symbol that describes the pattern of polygons surrounding each vertex, was devised in this book as a way to name the Archimedean solids, and has sometimes been called the Cundy–Rollett symbol as a nod to this origin.
Topics
The first edition of the book had five chapters, including its introduction which discusses model-making in general and the different media and tools with which one can construct models. The media used for the constructions described in the book include "paper, cardboard, plywood, plastics, wire, string, and sheet metal".
The second chapter concerns plane geometry, and includes material on the golden ratio, the Pythagorean theorem, dissection problems, the mathematics of paper folding, tessellations, and plane curves, which are constructed by stitching, by graphical methods, and by mechanical devices.
The third chapter, and the largest part of the book, concerns polyhedron models, made from cardboard or plexiglass. It includes information about the Platonic solids, Archimedean solids, their stellations and duals, uniform polyhedron compounds, and deltahedra.
The fourth chapter is on additional topics in solid geometry and curved surfaces, particularly quadrics but also including topological manifolds such as the torus, Möbius strip and Klein bottle, and physical models helping to visualize the map coloring problem on these surfaces. Also included are sphere packings. The models in this chapter are constructed as the boundaries of solid objects, via two-dimensional paper cross-sections, and by string figures.
The fifth chapter, and the final one of the first edition, includes mechanical apparatus including harmonographs and mechanical linkages, the bean machine and its demonstration of the central limit theorem, and analogue computation using hydrostatics. The second edition expands this chapter, and adds another chapter on computational devices such as the differential analyser of Vannevar Bush.
Much of the material on polytopes was based on the book Regular Polytopes by H. S. M. Coxeter, and some of the other material has been drawn from resources previously published in 1945 by the National Council of Teachers of Mathematics.
Audience and reception
At the time they wrote the book, Cundy and Rollett were sixth form teachers in the UK, and they intended the book to be used by mathematics students and teachers for educational activities at that level. However, it may also be enjoyed by a general audience of mathematics enthusiasts.
Reviewer Michael Goldberg notes some minor errors in the book's historical credits and its notation, and writes that for American audiences some of the British terminology may be unfamiliar, but concludes that it could still be valuable for students and teachers. Stanley Ogilvy complains about the inconsistent level of rigor of the mathematical descriptions, with some proofs given and others omitted, for no clear reason, but calls this issue minor and in general calls the book's presentation excellent. Dirk ter Haar is more enthusiastic, recommending it to anyone interested in mathematics, and suggesting that it should be required for mathematics classrooms. Similarly, B. J. F. Dorrington recommends it to all mathematical libraries, and The Basic Library List Committee of the Mathematical Association of America has given it their strong recommendation for inclusion in undergraduate mathematics libraries. By the time of its second edition, H. S. M. Coxeter states that Mathematical Models had become "well known".
References
Mathematical tools
Mathematics books
1952 non-fiction books | Mathematical Models (Cundy and Rollett) | [
"Mathematics",
"Technology"
] | 785 | [
"Applied mathematics",
"Mathematical tools",
"History of computing",
"nan"
] |
65,274,383 | https://en.wikipedia.org/wiki/Napin | Napin is one of the two most abundant seed storage proteins in the seeds of dicot crop mustard and rapeseed (Brassica napus L., B. juncea L. Czern., B. nigra L. W.D.J.Koch, B. rapa L. and Sinapis alba L.). They are water soluble low-molecular weight basic proteins classified as 2S or 1.7S proteins, representing 20–40% of total seed protein, and having a molecular weight in the range of 12–17 kDa. Their isoelectric point varies based on the method of extraction and the specific characteristics of the isoforms that exist. They are composed of two polypeptide chains, a 4.5 kDa small subunit and a large 10 kDa subunit, stabilized primarily by disulphide bonds. Their secondary structure shows a high α-helical content.
Properties
Arginine, lysine, and cysteine make napines excellent antibacterials, and since it is a basic protein, it can change its acidity to make it more effective. Some in silico and in vitro antimicrobial activity screening reported napins as antimicrobial and antifungal peptides.
Structure
As a basic protein, napin can be used to bind together and determine the shape, properties, and be able to synthesize when seeds develop.
Composition
In terms of molecular weights, napin polypeptide chains are made up of 9,900 and 4,000 amino acids held together by disulfide bonds .The amino acid sequence of napin cDNA clones and napin peptide fragments indicate napin starts as a 178-residue precursor.
Solubility
Napin is water soluble and soluble in a wide pH range.
References
Seed storage proteins | Napin | [
"Chemistry"
] | 377 | [
"Biochemistry stubs",
"Protein stubs"
] |
65,274,528 | https://en.wikipedia.org/wiki/Wisconsin%20National%20Primate%20Research%20Center | The Wisconsin National Primate Research Center (WNPRC) is a federally funded biomedical research facility located at the University of Wisconsin-Madison. The WNPRC is part of a network of seven National Primate Research Centers which conduct biomedical research on primates. As of 2020, the center houses approximately 1,600 animals.
Research
The WNPRC describes its mission to involve researching human diseases, studying primate biology, providing "expertise, resources and training" to scientists, and disseminating information about the center. In 2020, the center consisted of 1,600 animals, 190 employees, and 190 trainees.
Incidents and controversies
1960s and 1970s
During the 1960s and 1970s, psychologist Harry Harlow led experiments at the WNPRC in which young monkeys were subjected to social isolation, causing the monkeys to experience severe emotional distress. As part of his experiments, Harlow developed a device called the "pit of despair", which was an isolation chamber where young monkeys were kept for up to ten weeks.
2010–2014
In June 2012, a seven-month-old macaque died after its head was caught between a support bar and enclosure.
In July 2014, a USDA inspection report revealed that since January 1, 2013, there had been 36 incidents of non-human primates escaping from their enclosures. Five of these incidents involved significant injuries to the animals which required surgery or primary closure of wounds. Furthermore, many of these escapes were the result of human errors such as incorrectly closing or securing enclosures.
In February 2013, a five-year-old marmoset was killed as the result of improper use of an anesthesia machine by a veterinary technician.
In October 2013, a macaque sustained a thermal injury after a heat lamp, which was intended to warm the animal, malfunctioned.
In June 2014, a two-year-old macaque died after her head was caught in a chain her cage.
In 2014, psychiatrist Ned Kalin was approved for experiments in which newborn monkeys were to be separated from their mothers, subjected to anxiety-inducing tests, and then euthanized. Kalin's experiments sparked outrage and condemnation, and a petition against Kalin's experiments was signed by over 290,000 people.
In July 2014, a USDA inspection report revealed that since July 2014, there had been two incidents of non-human primates escaping their cages due to technician error, which resulted in the animals experiencing injuries which required amputation and closure of wounds. The same report revealed that there had been three incidents of animal mis-pairing due to technician error, which resulted in injuries and wounds to the animals.
2015–2019
In January 2016, a USDA inspection report revealed that there had been 12 incidents of primates escaping their enclosures. Nine of these cases were due to human error, and three were due to enclosure hardware failure. After their escape, many primates were injured after interacting with other primates. Some of these injuries involved primates losing portions of their tongues, and some required sutures and/or digit amputations.
In December 2015, it was discovered that a drinking water supply line for three rhesus macaques had been disconnected for one to four days. The animals were given IV fluid therapy. After the therapy, two of the animals recovered, but the third did not and was euthanized.
In June 2018, a USDA inspection report revealed that since November 2016, there had been four incidents of macaques escaping their enclosures due to human error or enclosure failure. After escaping, the macaques interacted with other macaques and sustained injuries, which required sutures and/or digit amputation.
In October and November 2017, a marmoset got its foot closed on by an enclosure door on two occasions. As a result, the animal's foot was injured and required digit amputations.
In February and March 2019, primates escaped their enclosures after locks were improperly installed. After their escape, the animals interacted with other primates and sustained injuries. Some of the injuries required surgical repair including sutures, digit amputation, and tongue loss.
In July 2019, a USDA inspection report revealed that as the result of a handling procedure, a marmoset had sustained a femur fracture that required amputation.
2020–present
In February 2021, a marmoset sustained a foot injury after a door was accidentally closed on its foot. The injury required multiple surgeries and digit amputations.
In August 2021, the USDA reported seven incidents over the past two years due to improper handling by the staff, which caused injuries to multiple primates. The affected primates sustained injuries including partial loss of their tongues, tail injuries, injuries which required digit amputation, and wounds that required sutures. Most injuries were due to interactions between primates after not being properly contained. Of the seven incidents, three were caused by the staff's improper use of locks, and four were caused by the staff's improper use of transport boxes.
References
External links
WNPRC home page
Primate research centers
Animal testing on non-human primates
University of Wisconsin–Madison
Medical research institutes in the United States
Biomedical research foundations
Research institutes in Wisconsin | Wisconsin National Primate Research Center | [
"Engineering",
"Biology"
] | 1,056 | [
"Biotechnology organizations",
"Biomedical research foundations"
] |
70,894,761 | https://en.wikipedia.org/wiki/Ideal%20reduction | The reduction theory goes back to the influential 1954 paper by Northcott and Rees, the paper that introduced the basic notions. In algebraic geometry, the theory is among the essential tools to extract detailed information about the behaviors of blow-ups.
Given ideals J ⊂ I in a ring R, the ideal J is said to be a reduction of I if there is some integer m > 0 such that . For such ideals, immediately from the definition, the following hold:
For any k, .
J and I have the same radical and the same set of minimal prime ideals over them (the converse is false).
If R is a Noetherian ring, then J is a reduction of I if and only if the Rees algebra R[It] is finite over R[Jt]. (This is the reason for the relation to a blow up.)
A closely related notion is that of analytic spread. By definition, the fiber cone ring of a Noetherian local ring (R, ) along an ideal I is
.
The Krull dimension of is called the analytic spread of I. Given a reduction , the minimum number of generators of J is at least the analytic spread of I. Also, a partial converse holds for infinite fields: if is infinite and if the integer is the analytic spread of I, then each reduction of I contains a reduction generated by elements.
References
Commutative algebra | Ideal reduction | [
"Mathematics"
] | 282 | [
"Fields of abstract algebra",
"Commutative algebra"
] |
70,895,208 | https://en.wikipedia.org/wiki/Mikhail%20Gelfand | Mikhail Sergeyevich Gelfand (; born 25 October 1963) is a Russian Bioinformaticist and molecular biologist. He is a member of Academia Europaea, Vice President Biomedical Research of Skolkovo Institute of Science and Technology, one of the founder of Dissernet plagiarism fighting society and a political activist, former member of Russian Opposition Coordination Council. He is a grandson of a prominent Soviet mathematician Israel Gelfand.
Some works by Mikhail Gelfand
Gelfand M. S. Statistical analysis of mammalian pre-mRNA splicing sites // Nucleic Acids Research. 1989. V. 17. N. 15. 6369–6382.
Gelfand M. S. Computer prediction of the exon-intron structure of mammalian pre-mRNAs // Nucleic Acids Research. 1990. Y. 18. N. 19. P. 5865–5869.
Gelfand M. S. Statistical analysis and prediction of the exonic structure of human genes // Journal of Molecular Evolution. 1992. Y. 35. N. 2. P. 239–252.
Gelfand M. S. Genetic language: metaphore or analogy // BioSystems. 1993. V. 30. P. 277—288
Pevzner Р. А., Gelfand M. S., eds. Computer Genetics. A special issue on computational molecular biology // BioSystems. 1993. V. 30.
Gelfand M. S., Mironov A. A., Pevzner P. A. Spliced alignment: a new approach to gene recognition // Lecture Notes in Computer Science. 1996. V. 1075. P. 141–158.
Gelfand M. S., Mironov A. A., Pevzner P. A. Gene recognition via spliced sequence alignment // Proceedings of the National Academy of Sciences. 1996. V. 93. P. 9061–9066.
Gelfand M. S., Koonin E. V. Avoidance of palindromic words in bacterial and archaeal genomes: a close connection with restriction enzymes // Nucleic Acids Research. 1997. V. 27. P. 2430–2439.
Sze S.-H, Roytberg М. А., Gelfand M. S., Mironov A. A., Astakhova T. V., Pevzner P. A. Algorithms and software for support of gene identification experiments // Bioinformatics
Mironov A. A., Roytberg M. A., Pevzner P. A., Gelfand M. S. Performance guarantee gene predictions via spliced alignment // Genomics
Awards and honors
In 2022, Gelfand was elected as a Fellow of the International Society for Computational Biology.
References
External links
Gelfand publications on Зubmed
Popular science videos by Gelfand on Youtube
Russian bioinformaticians
Russian geneticists
Molecular biologists
Russian activists
1963 births
Living people
Moscow State University alumni
Members of Academia Europaea
Academic staff of the Higher School of Economics
Academic staff of Moscow State University
Russian science communicators | Mikhail Gelfand | [
"Chemistry"
] | 672 | [
"Molecular biologists",
"Biochemists",
"Molecular biology"
] |
70,895,881 | https://en.wikipedia.org/wiki/Abell%2048 | Abell 48 is a planetary nebula likely located around 14,000 light years away in the constellation of Aquila. It is noteworthy among planetary nebulae for hosting a rare WN-type Wolf-Rayet-type central star, a [WN4]-type star, which was once thought to be a bona-fide Wolf-Rayet star, and received the name WR 120–6. The nebula is made up of two rings surrounding the central star, and is heavily reddened, with an E(B-V) value of 2.14 and a visual extinction of 6.634 magnitudes, which is why it appears so dim.
Properties
Assuming a distance of 1.9 kiloparsecs (about 6,200 light years), the nebula would have a diameter of 0.38 parsecs (~1.24 light years), and would be about 6,500 years old. The central star, with an initial mass of approximately 3 solar masses, would have left the asymptotic giant branch (AGB) approximately 9,000 years ago. The central star of this nebula would be about 5,500 times brighter than the Sun, with a surface temperature of around 70,000 Kelvins and a size just under half that of the Sun. However, this may be slightly inaccurate given the different distance suggested by Gaia, which is about 67% larger than the one used in the study to derive the aforementioned properties.
References
Planetary nebulae
Aquila (constellation)
Wolf–Rayet stars | Abell 48 | [
"Astronomy"
] | 317 | [
"Aquila (constellation)",
"Constellations"
] |
70,895,914 | https://en.wikipedia.org/wiki/Villy%20Sundstr%C3%B6m | Villy Sundström (born February 6, 1949) is a Swedish physical chemist known for his work in ultrafast science and molecular photochemistry using time-resolved laser and X-ray spectroscopy techniques.
Education and career
Sundström studied chemistry at Umeå University, obtaining his PhD in 1977. During his study, he visited Bell Labs and worked under Peter Rentzepis. Upon his return to Sweden, he started building the first ultrafast spectroscopy laboratory in Scandinavia at Umeå University and later at Lund University in Sweden. In 1994, Sundström was appointed professor of Chemical Dynamics and head of the Chemical Physics Department at Lund University. His group's research centers on the photophysics and photochemical processes in model systems of natural and artificial photosynthetic light harvesting, such as bacteriochlorophyll, carotenoids, transition metal complexes, organic and perovskite solar cells.
Sundström was an editor of the journal Chemical Physics Letters.
Bibliography
Selected articles
Reviews
Books
References
1949 births
Swedish chemists
Umeå University alumni
Academic staff of Lund University
Academic staff of Umeå University
Spectroscopists
Swedish physical chemists
Photochemists
Living people
Scientists at Bell Labs
20th-century Swedish chemists
21st-century Swedish chemists | Villy Sundström | [
"Physics",
"Chemistry"
] | 257 | [
"Physical chemists",
"Spectrum (physical sciences)",
"Analytical chemists",
"Photochemists",
"Spectroscopists",
"Spectroscopy"
] |
70,896,112 | https://en.wikipedia.org/wiki/Tetraiodine%20nonoxide | Tetraiodine nonoxide is an iodine oxide with the chemical formula I4O9.
Preparation
Tetraiodine nonoxide can be produced by reacting ozone and iodine in carbon tetrachloride at −78 °C:
It can also be produced by heating iodic acid and phosphoric acid together:
Properties
Tetraiodine nonoxide is a light yellow solid that can easily hydrolyze. It decomposes above 75 °C:
Like diiodine tetroxide, tetraiodine nonoxide contains both I(III) and I(V), and disproportionate to iodate and iodide under alkaline conditions:
It reacts with water to form iodic acid and iodine:
References
Iodine compounds
Oxides | Tetraiodine nonoxide | [
"Chemistry"
] | 161 | [
"Salts",
"Oxides",
"Inorganic compounds",
"Inorganic compound stubs"
] |
70,901,258 | https://en.wikipedia.org/wiki/EA-1763 | EA-1763, O-PPVX, V1 or propyl S-2-diisopropylaminoethylmethylphosphonothiolate is a military-grade neurotoxic organophosphonate nerve agent related to VX as it is the propyl analogue of VX. It is part of the V-series.
Chemical characteristics
Little information about EA-1763's physicochemical properties has been reported. V1 is a more viscous and less dense liquid than VX. It is colorless, odorless and tasteless in its pure form. When impure or in the crude form, it has a characteristic viscous amber color, giving it an appearance similar to motor oil. The appearance of the impure form varies between several shades of amber, from a viscous liquid of a transparent pale yellow color to a pasty liquid of a semi-transparent and cloudy dirty amber color. The smell varies from engine oil to an offensive brew of organosulfur compounds and organoamines.
Its larger alkane chain pushes its melting point above that of VX. The estimated solubility of V1 in water is 4 times lower compared to VX (6.8 g/L of water at 25 °C). V1 has high solubility in organic solvents and other non-polar compounds. The stability of V1 is roughly the same as that of VX in either environment. Higher insolubility and lower volatility can slow down the process. A vapor pressure at least 3 times lower than VX is speculated.
The longer alkane chain tends to stabilize the induction of electrons from P to O, making P less electrophilic. It is expected that the persistence of V1 is slightly higher than that of VX since the hydrolysis rate of ethyl paraoxon is 1.6 times higher than the one of n-propyl paraoxon in a neutral medium.
The lower volatility and minimal persistence difference makes VX preferable to V1.
Preparation
It is prepared by the same route as VX using propanol instead of ethanol.
References
V-series nerve agents
Phosphonothioates
Chemical weapons of the United States
Diisopropylamino compounds | EA-1763 | [
"Chemistry"
] | 468 | [
"Phosphonothioates",
"Functional groups"
] |
70,903,214 | https://en.wikipedia.org/wiki/Pretenellin%20A | Pretenellin A is a secondary metabolite in Aspergillus oryzae. Pretenellin A is a substrate for tenellin because it undergoes an oxidative ring expansion to form Pretenellin B followed by N-hydroxylation to form Tenellin, an iron chelator in entomopathegnic fungus.
Biosynthesis
Pretenellin A is biosynthesized using acetate in the initiation module. The acetate molecule is then extended four times by iterative PKS (Figure 1). The specific methylations occur after the first and second elongation module. After the four elongation module, the β-ketopentaketide is brought into close proximity with tyrosine which is attached to a non-ribosomal peptide synthetase (NRPS) (Figure 2). When the iterative PKS interacts with the NRPS system Pretenellin A is released, acting as a well-regulated off-loading mechanism thus releasing Pretenellin A.
References
Secondary metabolites
Aspergillus compounds
4-Hydroxyphenyl compounds
Pyrroles
Dienes
Ketones | Pretenellin A | [
"Chemistry"
] | 248 | [
"Chemical ecology",
"Secondary metabolites",
"Ketones",
"Functional groups",
"Metabolism"
] |
70,903,695 | https://en.wikipedia.org/wiki/EP%20Aquarii | EP Aquarii is a semiregular variable star in the equatorial constellation of Aquarius. At its peak brightness, visual magnitude 6.37, it might be faintly visible to the unaided eye under ideal observing conditions. A cool red giant on the asymptotic giant branch (AGB), its visible light brightness varies by about 1/2 magnitude over a period of 55 days. EP Aquarii has a complex circumstellar envelope (CSE), which has been the subject of numerous studies.
In 1877, John Birmingham published a set of ten magnitude estimates for EP Aquarii (number 596 on his list) made during the 1870s, which ranged from magnitude 6 to 8. He listed the star as "Variable (?)", although he also claimed to have observed "a quick change" in magnitude. Birminghan's magnitude range is far wider than the 6.37 to 6.82 range listed in the GCVS, nonetheless Birmingham's publication was cited as the reference when EQ Aquarii received its variable star designation in 1973.
The study of EP Aquarii's extended CSE began in 1984, when a spectral line arising from a rotational transition of carbon monoxide (CO) was detected by Zuckerman and Dyck, using the NRAO 12m telescope. In the early 1990s, analysis of the IRAS satellite data showed the presence of an extended dust shell surrounding the star, with a radius of about 1 lightyear. In the late 1990s, high spectral-resolution observations at the Caltech Submillimeter Observatory (CSO) showed that EP Aquarii's CO line profiles had an unusual shape that suggested the presence of two distinct stellar winds, expanding at dramatically different velocities: 1.4 and 11 km/sec. In the early 2000s, observations of the 21 cm line of atomic hydrogen at the Nançay Radio Observatory confirmed the presence of a large circumstellar shell with multiple velocity components.
The completion of Atacama Large Millimeter Array allowed EP Aquarii to be studied with far higher sensitivity and angular resolution than was available to earlier researchers. The very narrow emission feature (indicating an expansion rate of 1.4 km/sec) seen in the CSO spectra was found to arise from a spiral structure, nearly face-on to our line of sight, which suggested the presence of an unseen companion star. The higher velocity wind arises from a bi-conical outflow, the pole of which is roughly aligned to our line of sight.
Which chemical compounds are found in the CSEs of AGB stars is largely determined by whether or not the stellar atmosphere contains more carbon than oxygen. EP Aquarii's atmosphere contains more oxygen than carbon.
References
M-type giants
Semiregular variable stars
Aquarius (constellation)
Durchmusterung objects
207076
107516
Aquarii, EP | EP Aquarii | [
"Astronomy"
] | 599 | [
"Constellations",
"Aquarius (constellation)"
] |
70,904,996 | https://en.wikipedia.org/wiki/Rio%20scale | The Rio scale was proposed in 2000 as a means of quantifying the significance of a SETI detection. The scale was designed by Iván Almár and Jill Tarter to help tell policy-makers how likely, from 0 to 10, it is that an extraterrestrial radio signal has been produced by an intelligent civilization.
The scale is inspired by the Torino scale, which is used to determine the impact risk associated with near-Earth objects. Just as the Torino scale takes into account how significant an object's impact on the planet would be, the Rio scale takes into account how much a public announcement of the discovery of extraterrestrial intelligence would probably impact society.
The IAA SETI Permanent Study Group officially adopted the Rio scale as a way of bringing perspective to claims of extraterrestrial intelligence (ETI) detection, and as an acknowledgement that even false ETI detections may have disastrous consequences.
The scale was modified in 2011 to include a consideration of whether contact was achieved through an interstellar message or a physical extraterrestrial artifact, including all indications of intelligent extraterrestrial life such as technosignatures. A 2.0 version of the scale was proposed in 2018.
Calculation
In its 2.0 version, the Rio Scale, R, of a given event is calculated as the product of two terms.
The first term, Q, is the significance of the consequences of an event. It is determined considering three factors: the estimated distance to the source of the signal (a value between 0 and 4), the prospects for communicating with the source (a value between 0 and 4) and how likely is that the sender is aware of humanity (a value between -1 and 2). The value of each factor is determined by answering a question and Q is calculated by summing the three values.
The second term, δ, is the probability that the event actually occurred. Its value is determined by first calculating a term, J, based on three factors: the probability that the signal is real, the probability that it is not instrumental, and the probability that it is not natural or human-made. The values for these factors are determined by answering a questionnaire and J is calculated by summing them. δ is then calculated using the formula .
The final R value, going from 0 to 10, is the likelihood that the observed event was produced by an intelligent civilization.
Rating scale
See also
Quiet and loud aliens
San Marino Scale
References
Search for extraterrestrial intelligence
Extraterrestrial life
Interstellar messages | Rio scale | [
"Astronomy",
"Biology"
] | 516 | [
"Astrobiology stubs",
"Hypothetical life forms",
"Extraterrestrial life",
"Astronomy stubs",
"Astronomical controversies",
"Biological hypotheses"
] |
70,905,576 | https://en.wikipedia.org/wiki/Black%20Shark%203 | Black Shark 3 or Black Shark Pro are line of Android-based gaming smartphones developed and manufactured by Xiaomi as part of its Black Shark product line. It is the successor to the Black Shark 2 line and was launched on March 03, 2020.
References
Android (operating system) devices
Mobile phones introduced in 2020
Xiaomi smartphones
Mobile phones with multiple rear cameras
Mobile phones with 4K video recording
Discontinued flagship smartphones | Black Shark 3 | [
"Technology"
] | 85 | [
"Discontinued flagship smartphones",
"Flagship smartphones"
] |
70,908,480 | https://en.wikipedia.org/wiki/Cercosporin | Cercosporin is a red toxin created by the fungal genus Cercospora. Cercospora act as pathogens on a variety of plants including corn, tobacco, soybean, and coffee. Cercosporin is a perylenequinone natural product that is photoactivated and uses reactive oxygen species (ROS) to damage cell components (membranes, proteins, lipids, etc.).
Biosynthesis
Light is required for biosynthesis and activation of cercosporin, and it has been demonstrated that light, temperature, and culture medium are regulating factors in the production of cercosporin.
Cercosporin is biosynthesized via polyketide synthases, and there are several genes that have been found responsible in the creation of the natural product. Overall, there are 8 CTB enzymes (CTB1-8) that contribute to the production of cercosporin. CTB1 (cercosporin toxin biosynthesis) is a non-reducing PKS consisting of a KS, AT, TE/CYC and 2 ACP domains that are vital in the initiation of the creation of cercosporin. The other CTB enzymes are not as well studied, but play important roles in the biosynthesis. CTB2 acts as a methyl transferase, CTB3 also functions as a methyl transferase but also functions as a FAD-dependent monoxygenase, CTB4 is a MFS transporter, CTB5 is a FAD-dependent oxidoreductase, CTB6 is a NADPH-dependent ketone reductase, CTB7 is another FAD-dependent monoxygenase, and CTB8 is a transcription factor that regulates expression of the cluster. Figure 1 shows a general depiction of the proposed biosynthesis. As a result of the two hydroxypropyl substituents and the two oxygen substituents of the acetal linker, the perylene core twists out of planarity. The natural product occurs as a single atropisomer.
Plant defense and susceptibility
To combat the onset of disease caused by Cercospora fungi, it has been proven that growing plants in lower light intensities can reduce the amount and severity of lesions caused by cercosporin. Some plant species use chitinases as a general defense mechanism to stop fungal infections. It has been observed that cercosporin-producing fungi that contain the Avr4 gene produce an effector that acts as a chitin-binding protein, allowing the fungi to be more virulent.
References
Heterocyclic compounds with 6 rings
Oxygen heterocycles
Dioxepines
Toxins
Methoxy compounds
Hydroxyarenes
Secondary alcohols
Hydroxyketones
Fungal pigments | Cercosporin | [
"Environmental_science"
] | 587 | [
"Toxins",
"Toxicology"
] |
70,910,604 | https://en.wikipedia.org/wiki/HD%20196775 | HD 196775 (HR 7899) is a solitary star in the equatorial constellation Delphinus. It has an apparent magnitude of 5.98, allowing it to be faintly seen with the naked eye. The object is relatively far at a distance of 1,050 light years but is approaching the Solar System with a heliocentric radial velocity of . HD 196775 has a high peculiar velocity of compared to neighboring stars, indicating that it may be a runaway star.
HD 196775 has a general stellar classification of B3 V, indicating that it is an ordinary B-type main-sequence star. However, once source gives it a class of B4 Vn, making it slightly cooler and having broad absorption lines due to rapid rotation. It has an angular diameter of , yielding a radius 4.13 times that of the Sun. At present it has 7 times the mass of the Sun and shines at from its photosphere at an effective temperature of , giving it a whitish blue hue. HD 196775 is 36 million years old and is spinning rapidly with a projected rotational velocity of .
HD 196775 has four faint optical companions whose parameters are listed below.
References
Delphinus
B-type main-sequence stars
196775
101909
7899
+15 4220
Runaway stars | HD 196775 | [
"Astronomy"
] | 261 | [
"Delphinus",
"Constellations"
] |
70,910,753 | https://en.wikipedia.org/wiki/Alfred%20Oxner | Alfred Mycolayovych Oxner (; ) (15 February 1898 – 20 November 1973) was a Ukrainian botanist and lichenologist. His research covered various areas: floristics, taxonomy, phylogenetics, phytogeography, and phytosociology. Oxner founded the National Lichenological Herbarium of Ukraine.
Biography
Alfred Nikolaevich Oxner was born on 15 February 1898 in Elizavetgrad (now Kropyvnytskyi, Ukraine). Although his family was of German nobility, they kept their origins and nationality secret during the time of the former socialist regime. The names of his real parents, Nicolay Ochsner, an ensign in the reserve and a farmer, and his mother Wilgelmine (née Schwartz), are on his birth certificate. However, he grew up with the families of his foster mother Zinaida Lazarevna Solomonova and her brother Mozyrj Lazarevich Solomonov.
In 1917, after graduating from the Elisavetgrad Gymnasium, Oxner entered Kyiv University (physical and mathematical faculty), from which he graduated in 1924. At university Oxner heard lectures from and was influenced by prominent Soviet scientists such as Aleksandr Fomin, Mykola Kholodny, and Ivan Schmalhausen. As a student he studied botany at the A.V. Fomin Botanical Garden at the University. From 1920 to 1924 he worked as a teacher in secondary schools, then he was engaged in teaching at the Kirovograd Agricultural College. He was appointed as a post-graduate student and began research at the herbarium of the Botanical Garden. In his spare time he studied the local flora, and subsequently published one of his first scientific papers, entitled "Some rare plants of the Zinov’iv District of the Kherson Region". Although lichens later became his main focus, he maintained an interest in vascular plants, and continued to work on the taxonomy of the family Liliaceae; this work was later published in the first edition of Flora of Ukraine.
As a student Oxner undertook several botanical expeditions to Ukraine and Belarus, where he collected many plants, mosses, and lichens. This field research resulted in the 1924 publication "Additions to the Flora of the Lichens of Belarus".
In 1926, Oxner became a senior researcher at the Department of Botany of the People's Commissariat for Education of the Ukrainian SSR. This department was taken over in 1927 by the Institute of Botany of the People's Commissariat of Education, and in 1931 the institute was transferred to the jurisdiction of the Academy of Sciences of the Ukrainian SSR. Since 1931 Oxner worked at the Institute of Botany of the Academy of Sciences of the Ukrainian SSR. In 1935 he received his candidate degree in biological sciences without defending a dissertation (a distinction called honoris causa). World War II interrupted his studies, and in 1942 he evacuated to Kirov, working there as a teacher at a secondary school. He continued to work on his thesis, and that same year defended his doctoral thesis, "Analysis and History of the Arctic Lichen Flora Origin".
After that he was given the title of Professor at Kyiv University. In 1968, Oxner was elected director of the Institute of Botany, a position he kept until 1970. In 1972 he became a corresponding member of the Academy of Sciences of the Ukrainian SSR. Alfred Nikolaevich Oxner died on 20 November 1973.
Selected works
Kondratyuk, S.Y., Kärnefelt, I., Goward, T., Galloway, D.J., Kudratov, I., Lackovičová, A., Lisická, E. & Guttová, A. 2010. Diagnoses of new taxa. In Oxner, A.M. (Ed. Kondratyuk, S.Y. & Roms, O.G.), Flora lyshaynykiv Ukrainy (Флора лишайників України). [Flora of the Lichens of Ukraine] 2(3): 435–445.
Kondratyuk, S.Y., Dymytrova, L.V. & Nadyeina, O.V. 2010. The third checklist of lichen-forming and allied fungi of Ukraine. In Oxner, A.M. (Ed. Kondratyuk, S.Y. & Roms, O.G.), Flora lyshaynykiv Ukrainy (Флора лишайників України). [Flora of the Lichens of Ukraine] 2(3): 446–486.
Recognition
In 1998, on the occasion of the 100th anniversary of the birth of Alfred Oxner, the Institute of Botany. N.G. Kholodny founded a prize with his name, awarded to young lichenologists every 2–3 years.
Eponyms
Four genera are named after Alfred Oxner: Oxnerella ; Oxneria ; Oxneriaria ; and Oxneriopsis .
Several species have also been named in his honour, including: Lecanora oxneri ; Melaspilea oxneri ; Porina oxneri ; Cladonia oxneri ; Endopyrenium oxneri ; Physcia oxneri ; Ascochyta alfrediae ; Aspicilia oxneriana ; Haematomma oxneri ; Xanthoria oxneri ; Caloplaca oxneri ; Xanthoria alfredi ; Ivanpisutia oxneri ; Rinodina oxneriana ; Staurothele oxneri ; Leptosphaeria oxneriae ; and Hyperphyscia oxneri .
See also
:Category:Taxa named by Alfred Oxner
References
1898 births
1973 deaths
Lichenologists
20th-century Ukrainian scientists
Taras Shevchenko National University of Kyiv alumni
Scientists from Kropyvnytskyi
Taxonomists | Alfred Oxner | [
"Biology"
] | 1,257 | [
"Taxonomists",
"Taxonomy (biology)"
] |
70,911,322 | https://en.wikipedia.org/wiki/Rubicon%20homology%20domain | The Rubicon homology domain (also known as RH domain) is an evolutionarily conserved protein domain of approximately 250 amino acids that mediates protein–protein interaction. RH domains are present in several human proteins involved in regulation of autophagy and endosomal trafficking. While not all RH domains have been characterized, those of human Rubicon and PLEKHM1 mediate interaction with the small GTPase Rab7, which is found on late endosomes and autophagosomes.
RH domains contain 16 conserved cysteine and histidine residues that bind zinc atoms and form at least 4 zinc finger motifs. Amino acid residues toward the C-terminus of the RH domain of Rubicon have been shown to be essential for interaction with Rab7.
Structure
The 3D atomic structure of the Rubicon RH domain in complex with Rab7 has been determined by X-ray crystallography. The structure of the RH domain has an "L" shape, with the base of the "L" making contact with the switch regions of Rab7. The structure is predominantly alpha helical, with short beta strand regions present in the vicinity of zinc finger motifs. The N-terminal region of the Rubicon RH domain resembles a FYVE domain, however the basic residues required for canonical FYVE domain binding of PI3P are not present.
Proteins containing an RH domain
RH domains are found in a number of proteins, including (in humans):
Rubicon, the defining member of the RH domain-containing family of proteins and a negative regulator of autophagy
PLEKHM1, a protein implicated in osteopetrosis
Pacer, a positive regulator of autophagy
DEF8, a regulator of lysosome peripheral distribution
PLEKHM3, involved in skeletal muscle differentiation
References
Protein domains
Protein structure | Rubicon homology domain | [
"Chemistry",
"Biology"
] | 384 | [
"Protein structure",
"Protein domains",
"Structural biology",
"Protein classification"
] |
61,508,642 | https://en.wikipedia.org/wiki/Sang%20de%20boeuf%20glaze | Sang de boeuf glaze, or sang-de-boeuf, is a deep red colour of ceramic glaze, first appearing in Chinese porcelain at the start of the 18th century. The name is French, meaning "ox blood" (or cow blood), and the glaze and the colour sang de boeuf are also called ox-blood or oxblood in English, in this and other contexts.
Sang de boeuf was one of a number of new "flambé" glazes, marked by "unpredictable but highly decorative and varying effects", developed in the Jingdezhen porcelain kilns during the Kangxi reign (1662–1722). According to one scholar: "In its finer examples, this spectacular glaze gives the impression that one is gazing through a limpid surface layer, which is slightly crazed and strewn with countless bubbles, to the color that lies underneath".
As with most Chinese red glazes, the main colouring agent is copper oxide, fired in a reducing atmosphere (without oxygen); finishing them in an oxidizing atmosphere may have been part of the process. From the late 19th century onwards, usually after lengthy experiment, many Western potters produced versions of the Chinese glaze, which is technically very difficult to achieve and control.
For Chinese ceramics, some museums and books prefer the term "sang de boeuf", some "oxblood", in both cases with varying use of hyphens, and capitals and italics for "sang de boeuf". The most common Chinese name for the glaze is lángyáohóng (郎窑红, "Lang kiln red"). Another Chinese name for this type of glaze is niúxiěhóng (牛血红, "ox-blood red/sang de boeuf").
Chinese sang de boeuf
Origin as imitation of Ming wares
Sang de boeuf glaze was apparently developed around 1705–1712 in an attempt to recover the lost "sacrificial red" glaze of the Xuande reign (1426–35) of the Ming dynasty. This was a very famous glaze used for ceremonial (ritual) wares made at Jingdezhen, of which very few examples survive from his short reign.
As recorded in the Collected Statutes of the Ming Dynasty, from 1369, the second year of Hongwu Emperor's reign at the beginning of the Ming dynasty, monochrome porcelains replaced other materials for the ritual vessels used in the official rituals of sacrifices the emperor was required by tradition to perform, hence the name "sacrificial red". Chinese names for it are xiānhóng (鲜红, "fresh red") and bǎoshíhóng (宝石红, "ruby red"). The statute also states that each colour was associated with a specific direction and ritual: "To each direction is associated a porcelain: red for the altar of the Sun, blue for that of Heaven, yellow for the Earth and white for the Moon".
The sacrificial red developed under Xuande ceased to be produced after the emperor's death, and has never been perfectly imitated, despite many later attempts. This suggests the close personal interest some emperors took in the imperial potteries, and also that some secrets must have been restricted to a small group of potters.
Qing sang de boeuf
Monochrome glazes like sang de boeuf enjoyed a revival in the Qing dynasty, for whom they evoked what were regarded as the high points of historical Chinese ceramics under the early Ming and the Song dynasty (960–1279). They were produced for the imperial court at Jingdezhen alongside completely different styles painted with elaborate designs using newly expanded palette of colours in overglaze enamels, known as famille rose, famille verte and so on, based on the dominant colour. Initially, much of this production was for sale, often as Chinese export porcelain, where the court preferred simpler decoration.
Where the Xuande sacrificial red pieces have a very subtle mottled coverage, sang de boeuf was produced with a variety of shades of colour and as well as mottling, streaked effects in the glaze, which often fades to white at the top of pieces, and conversely thickens around the shoulders of vases and at the foot, which is often not fully covered by the glaze. There is often crackle, and a greenish tinge at the edges of the glazed area, where the glaze is thin. All of these were considered desirable effects. Generally the glaze is only applied to the outside of closed shapes, the inside and rim left with a clear glaze. The red glaze was probably applied by spraying. Other colours that may appear are turquoise, lavender, and purple.
The great number of very sensitive variables meant that the glaze colour and effects were initially not reliably controlled by the makers, leaving an element of randomness that appealed to Chinese aesthetics. By the late 18th century more control was possible.
Western versions
In the 19th century various Western potters, especially in the emerging art pottery movement, tried to copy the Chinese glaze, which had acquired a great reputation, but found replicating it very difficult, whether in porcelain or stoneware. In France Sèvres porcelain began experimenting in 1882. Ernest Chaplet succeeded in making it in 1885, with financial backing from Haviland & Co., and Pierre-Adrien Dalpayrat also succeeded in making a version. Chaplet won a gold medal at the 1889 Exposition Universelle in Paris for his glaze.
The American Hugh C. Robertson, of the Chelsea Keramic Art Works in Chelsea, Massachusetts, became interested in Oriental glazes on seeing them at the Philadelphia Exposition of 1876 and a "preoccupation with glazes was to obsess Robertson for the rest of his career". He finally developed a version of sang de boeuf in 1888, which he nicknamed Sang de Chelsea, but the following year, "nearly penniless from his costly experiments with the sang-de-boeuf glaze", he closed the pottery.
In England the Ruskin Pottery in Smethwick achieved a glaze around 1900; all their formulas were deliberately destroyed when the pottery closed in 1935. Another English art pottery which produced sang de boeuf was that of Bernard Moore. His pottery in Stoke-on-Trent specialised in flambé glazes from 1905 till the closure of the business in 1915.
From 1903, the English architect Leslie Green used an industrial, solid, sang de boeuf glaze on the glazed architectural terra-cotta tiles and decorative elements for the exteriors of the stations of a large part of the London Underground system, which was then divided between a number of commercial companies. His employer, the Underground Electric Railways Company of London was building the Great Northern, Piccadilly and Brompton Railway, the Baker Street and Waterloo Railway and the Charing Cross, Euston and Hampstead Railway, which are now respectively sections of the Piccadilly line, Bakerloo line and Northern line. The Leeds Fireclay Company made the tiles.
The American ceramist Fance Franck (1931–2008) extensively researched copper red glazes in her workshop in Paris leading to the rediscovery of the Ming technique. She was supported by the Percival David Foundation of Chinese Art.
Notes
References
Battie, David, ed., Sotheby's Concise Encyclopedia of Porcelain, 1990, Conran Octopus,
Burke, Doreen Bolger; Frelinghuysen, Alice Cooney, In Pursuit of Beauty: Americans and the Aesthetic Movement, 1986, Metropolitan Museum of Art, , 9780870994685, google books
"Ellison": Frelinghuysen, Alice Cooney; Eidelberg, Martin; Spinozzi, Adrienne, American Ceramics, 1876–1956: The Robert A. Ellison Jr. Collection, 2018, Metropolitan Museum of Art, , 9781588395962, google books
Franck, Fance, L'Œuvre au rouge. Étude de la porcelaine xianhong, 1993, The Baur Collections, vol. 55 pp. 3–38
Nilsson, Jan-Erik, gothenborg.com "Langyao hong (Lang kiln red) also "oxblood" or sang de boef (fr.)"
Petrie, Kevin; Livingstone, Andrew, eds., The Ceramics Reader, 2017, Bloomsbury Publishing, , 9781472584434, google books
Pollock, Rebekah, "Elusive Oxblood", Cooper Hewitt, Smithsonian Design Museum, 2014
Savage, George, and Newman, Harold, An Illustrated Dictionary of Ceramics, 1985, Thames & Hudson,
Sullivan, Michael, The Arts of China, 1973, Sphere Books, (revised edn of A Short History of Chinese Art, 1967)
Vainker, S.J., Chinese Pottery and Porcelain, 1991, British Museum Press,
Valenstein, S. (1998). A handbook of Chinese ceramics (fully available online), Metropolitan Museum of Art, New York.
Wood, Frank L., The World of British Stoneware: Its History, Manufacture and Wares, 2014, Troubador Publishing Ltd, , 9781783063673
External links
Chinese porcelain
Ceramic glazes
Studio pottery
Art pottery | Sang de boeuf glaze | [
"Chemistry"
] | 1,941 | [
"Ceramic glazes",
"Coatings"
] |
61,509,283 | https://en.wikipedia.org/wiki/C18H17ClN2O2 | {{DISPLAYTITLE:C18H17ClN2O2}}
The molecular formula C18H17ClN2O2 (molar mass: 328.793 g/mol, exact mass: 328.0979 u) may refer to:
Girisopam
Oxazolam
Molecular formulas | C18H17ClN2O2 | [
"Physics",
"Chemistry"
] | 69 | [
"Molecules",
"Set index articles on molecular formulas",
"Isomerism",
"Molecular formulas",
"Matter"
] |
61,509,414 | https://en.wikipedia.org/wiki/C38H46F4N6O9S | {{DISPLAYTITLE:C38H46F4N6O9S}}
The molecular formula C38H46F4N6O9S (molar mass: 838.865 g/mol) may refer to:
Glecaprevir
Telotristat ethyl
Molecular formulas | C38H46F4N6O9S | [
"Physics",
"Chemistry"
] | 67 | [
"Molecules",
"Set index articles on molecular formulas",
"Isomerism",
"Molecular formulas",
"Matter"
] |
61,509,757 | https://en.wikipedia.org/wiki/Maximilian%20Cercha | Maximilian (also spelled Maksymilian) Cercha (1818–1907) was a Polish painter and drawer. He was the nephew of Ezechiel Cercha (1790–1820) and the father of (1867–1919).
Life
Cercha was born on in Kraków. He studied at the Jan Matejko Academy of Fine Arts and at the Painting and Drawing School at the Technical Institute in Kraków with , Jan Nepomucen Głowacki and Wojciech Stattler.
Cercha died in Kraków on and was buried at the Rakowicki Cemetery.
Among Cercha's students are his son, Stanisław Cercha, and Stanisław Tarnowski.
References
External links
1818 births
1907 deaths
Artists from Kraków
Draughtsmen
19th-century Polish painters
Polish male painters
Painters from Austria-Hungary | Maximilian Cercha | [
"Engineering"
] | 174 | [
"Design engineering",
"Draughtsmen"
] |
61,509,971 | https://en.wikipedia.org/wiki/Cromer%20cycle | The Cromer cycle is a thermodynamic cycle that uses a desiccant to interact with higher relative humidity air leaving a cold surface. When a system is taken through a series of different states and finally returned to its initial state, a thermodynamic cycle is said to have occurred. The desiccant absorbs moisture from the air leaving the cold surface, releasing heat and drying the air, which can be used in a process requiring dry air. The desiccant is then dried by an air stream at a lower relative humidity, where the desiccant gives up its moisture by evaporation, increasing the air's relative humidity and cooling it. This cooler, moister air can then be presented to the same cold surface as above to take it below its dew point and dry it further, or it can be expunged from the system.
The desiccant undergoes a reversible process whereby in the first part of the cycle, it absorbs or adsorbs moisture from air leaving a cold surface, releasing heat, and then in the second part of the cycle evaporates moisture, absorbing heat and returning the desiccant to its original state to complete the cycle again. The result of the Cromer cycle is that the process air leaving the cycle is dehumidified further (higher latent ratio) than it would be leaving the cold surface without the cycle. The Cromer cycle concept was originally patented in the mid-1980's. Those patents have expired and thus the cycle is free for anyone to use. The cycle was first publicized in 1997 by Popular Mechanics in its Tech Update section.
Psychrometrics
The Cromer cycle is primarily used in air conditioning and drying applications. The cold surface portion of the cycle is most often a result of a reversed Carnot or refrigeration cycle. For the Cromer cycle to operate, a desiccant must be exposed to two air streams, one with higher humidity from a cold surface, and one with lower humidity to dry it. This is most easily accomplished by moving the desiccant. Any cycling mechanism can be used, such as pumping a liquid desiccant, however an easy mechanical application is a rotating wheel, loaded with desiccant, through which the different air streams pass. This is shown in Figure 1 where a desiccant wheel has been applied to a standard air conditioning set-up.
The psychrometric process of the air passing through the system with four state points is shown on the psychrometric chart of Figure 2 as 1, 2, 3 and 4. The state points of the air are also depicted in Figure 1. In this application, the air returning from the space, typically around 50% relative humidity (RH), is presented to the desiccant wheel and dries the desiccant. The air picks up moisture and cools in process 1 to 2. The moist air is now presented to the cooling surface (cooling coil of the air conditioner), which cools it below its dew point and dries the air in process 2 to 3. This represents the work done by the cold coil. In the meantime, the dried desiccant from below is rotated to the upper air stream. The saturated air leaving the coil, typically 93–98% RH, is presented to the desiccant at 3, where the air is dried further in process 3 to 4, where it is presented to the space as supply air. The desiccant, now loaded with moisture, rotates to the return air, where the cycle repeats.
Typical cooling and drying by the cold coil without the Cromer cycle is depicted on the psychrometric chart and is also shown in Figure 2. State point 1 is the air that returns from the space to the system (return air). For a typical air conditioning system, this air at state point 1 enters the cooling coil and leaves at about state point 4' after cooling and drying. State point 4' represents the temperature and moisture content of the air that leaves the typical unit, about and 95–98% RH.
Changes to a standard AC system by the Cromer cycle
The psychrometric chart depicts the changes of the cycle to the standard air conditioning cycle. First, the end state point 4 for air from the wheel represents a latent ratio increase (moisture removal) to about 45%, as opposed to the 25% of the typical coil shown. Secondly, the air quality delivered by the cycle is much dryer, about 55% RH (state point 4), rather than 98% with the standard coil (state point 4'). Third, this is accomplished with a higher average evaporator temperature. Compare the midpoint of the evaporator's temperature, line 1 to 4’, to the midpoint of the Cromer cycle's evaporator's temperature, line 2 to 3. These lines represent the work done by the coil on the air stream (its change in enthalpy). This is significant because, given a constant condenser temperature and equivalent change in enthalpy, the higher the evaporator coil temperature, the more efficient is the Carnot refrigeration cycle and the greater the energy efficiency a particular system can deliver.
Common dehumidification strategies include: reheating (electric or hot-gas bypass), where sensible heat is added to the air leaving the equipment; recuperative heat (run-around coils or heat pipes), where sensible heat is transferred from the return air to the supply air; or the Cromer cycle, where the latent heat of moisture sorption and evaporation is transferred from the return air to the supply air. These various strategies were compared in an ASHRAE Journal article that found that "the Cromer cycle produces similar enhanced dehumidification performance as is obtained with recuperative configurations."
Desiccants used
To operate in this cycle, the desiccant is required to absorb moisture from air coming off of the coil that is colder and about 98% RH and to desorb moisture to air that is warmer and at a lower RH. The desiccant is regenerated by the vapor pressure differential inherent in the RH differences rather than heat or temperature difference. Desiccants that have a moisture sorption isotherm of the type shown in Figure 3 (Type III) are common, such as many formulations of silica gel. Type III desiccants absorb little moisture below 70% RH but many will take up more than their own weight in water from the air when presented with over 90% RH. The absorption isotherm is very steep between 90 and 100% RH. Desiccants of Type III have plenty of potential for the cycling of moisture from the air off of the coil, around 98% RH, over to the return air stream, typically around 50% RH.
Field tests
In 2011, Khalifa, Al-Omran, and Mohammed reported on a monitored study of a 2-ton capacity air conditioner unit while exchanging out a silica gel wheel and a wheel made of activated carbon to determine if it would reduce the relative humidity in a small room in Baghdad when compared to the unit without the Cromer cycle added. They found that the "Cromer cycle can reduce the indoor relative humidity from 80% to about 60% using active carbon of 5 cm wheel thickness."
Incorporating fresh air exchange
To maintain indoor air quality, it may be desirable to expunge return air from the conditioned space and replace it with fresh outdoor air, sometimes called "make-up air." The optimal location to expunge return air from a Cromer cycle system is just after the desiccant (location 2 on Figure 1). At this point, the return air has been loaded with moisture from the desiccant, and expunging it removes additional moisture from the space. Furthermore, this expunge air is cooled below the return air condition by the desiccant's evaporation of the moisture into it. Location 2 (but before the fan) is also the ideal place to bring outdoor air into the system, as the coil can then reduce its temperature and moisture before it enters the space. Also, if heat exchange is provided between the expunged air and the outdoor air, the incoming air can be cooled and brought near to or at saturation before it enters the cooling coil for process 2 to 3, enhancing its dehumidification.
Dehumidifier
When the process needed is more dehumidification or drying, the Cromer cycle can be enhanced by using the free heat available from the condensing side of the reverse Carnot refrigeration cycle. This heat, sometimes called "hot gas bypass" can be added before the desiccant wheel to enhance the drying of the wheel at location 1 of Figure 1 (but after the filter), called pre-heat. Hot gas bypass heat can also be added to the process at location 4, called reheat, which delivers warmer but even lower RH supply air. Either one or both hot gas bypass locations can be used. When a Cromer cycle air conditioning system is enhanced with hot gas bypass, it is typically referred to as "active" Cromer cycle air-conditioning. When the cycle is used as equipment designed for dehumidification or drying, it is typically called a Cromer cycle dehumidifier or Cromer cycle dryer.
R&D magazine recognized the Cromer cycle in 2006 with an R&D 100 Award in the mechanical/materials category, recognizing the year's 100 most significant technological innovations.
References
Thermodynamics
Desiccants | Cromer cycle | [
"Physics",
"Chemistry",
"Mathematics"
] | 2,039 | [
"Desiccants",
"Materials",
"Thermodynamics",
"Matter",
"Dynamical systems"
] |
61,510,140 | https://en.wikipedia.org/wiki/C15H23N5O2S | {{DISPLAYTITLE:C15H23N5O2S}}
The molecular formula C15H23N5O2S (molar mass: 337.440 g/mol, exact mass: 337.1572 u) may refer to:
GS-39783
Oclacitinib
Molecular formulas | C15H23N5O2S | [
"Physics",
"Chemistry"
] | 71 | [
"Molecules",
"Set index articles on molecular formulas",
"Isomerism",
"Molecular formulas",
"Matter"
] |
61,510,351 | https://en.wikipedia.org/wiki/Cadwork%20informatik%20AG | cadwork informatik CI AG is a multinational software company headquartered in Basel, Switzerland. It develops and markets software products primarily for the construction industry. These products include timber industry products in computer-aided design (CAD) and computer-aided manufacturing (CAM) as well as products in building information model (BIM) and virtual design and construction (VDC). These products are suitable for designers, structural engineers, construction engineers, civil engineering draftspeople, building contractors, and in the case of BIMTeam VDC, the construction crews.
cadwork integration of design, manufacturing, and construction has contributed to Europe's 25-year lead on North America in the timber construction industry. cadwork was formed in 1988 at the École Polytechnique Fédérale de Lausanne (EPFL) Department of Timber Construction as a continuation of research in software by the Swiss Center for Electronics and Microtechnology (CSEM), a watch industry research department. The company has seven subsidiaries with offices in Saône, France; Hildesheim, Germany; Rýmařov, Czech Republic; Breitenwang, Austria; Cuarte, Spain; Montréal, and Palo Alto in California.
Products
Products and technical details
cadwork is mainly known for its timber industry wood products, but in Switzerland, it is a leading software for civil engineers. In 2004, cadwork started the development of Lexocad, a BIM-level design-planning-construction software.
cadwork 2D: The entry-level module to cadwork 2d, with two-dimensional lines and surfaces with different hatches. It is a '2.5D CAD system', in addition to two-dimensional editing, cadwork 2d also allows for height information. Height information is particularly suitable for construction planning while transitioning from 2D to the 3D module, which in 3d provides for developing a tender for construction project competitions. An alternative to cadwork 2D is AutoCAD. A module of cadwork 2d allows for reinforced concrete and geographic information system (GIS) plans. The file format is .2d.
cadwork 3D: A timber 3D CAD/CAM design product. In cadwork 3d, one works with volumes to depict walls, generate wooden and steel rakes, and plan three-dimensional nodes space. The primary areas of application are timber and steel construction. cadwork 3D offers free volume models; an internal axis (length, width, and height) makes it possible to assemble the individual components easily into complex, three-dimensional structures. There are several additional modules, such as a wizard for entering a roof, an assistant for the elementation of walls, or also the output of the individual components as a dimensioned 2D component drawing or on computer numerical control (CNC) joinery machines. The Timber Engineering Reference described cadwork 3d as broadly featured with modules for heavy timber roof, heavy timber frame, log structures, panelization, CAM fabrication, parametric variant module, glulam lamination design, and a bill of materials. The file format is .3d.
cadwork 2dr/cadwork Engineer: An infrastructure design product with engineering features for topographic and road. The file format is .2dr.
cadwork Lexocad: A commercial BIM 3D design infraBIM product, which includes 4D scheduling, 5D pricing, and 6D execution. When combined with cadwork 2dr, Lexocad provides a BIM planning and construction interface for construction crews and construction engineers. Lexocad has free cadwork viewers, which allows zooming, panning, and printing; however, the freeware version does not allow modifying a file. The file format is .lxz.
cadwork BIMteam: A webGL model interface with total station functions; an alternative is Autodesk BIM 360.
cadwork BIMview: A webGL viewer.
Research and development collaborations
University:
cadwork informatik AG is an active member of the Center for Integrated Facility Engineering (CIFE), Stanford University.
cadwork informatik AG partnered on a "Science to Market" project with the Institute of 4D Technologies (i4Ds), University of Applied Sciences Northwestern Switzerland. This project included the Swiss Federation Innovation Agency (KTI/CTI) and industry partner Swiss Federal Railways Corporation (SBB) in Bern.
cadwork informatik AG supported the development of shadow algorithms at Brno University of Technology, Czech Republic
Industry: Swiss Research Centre for Rationalization in Building and Civil Engineering CRB, Basel; collaboration on integrating ontology representation through BIM of products, processes, and applied resources.
Software: BuildingSMART; collaboration on infra-BIM for roads, rail, bridges, and waterways.
Education and certifications
The cadwork customer base is a network of practitioners; through a long-term client relationship, cadwork continues software support, development of custom solutions, and application education.
In education, cadwork works with collaborators to provide continuing education opportunities, such as with the Tall Wood Institute.
In North America, cadwork collaborates with the Timber Framers Guild apprenticeship education in collaboration with the United Brotherhood of Carpenters and Joiners of America.
Manufacturing
cadwork is the primary fabrication software used by timber manufacturers globally, as such, cadwork has a diverse network of manufacturers throughout the world. To work in timber manufacturing, knowledge of cadwork is a criterion so to allow for operating and programming of CNC machines.
Modeling: Timber Frame Headquarters
Fabricators
Timber Artisans
Rocky Mountain Joinery
Euclid Timber Frames
Equipment
Dürr AG HOMAG woodworking tools
Hundegger machinery
Company history
cadwork informatik AG was founded in 1988 as a continuation of the research by the Swiss Center for Electronics and Microtechnology (CSEM) and the École Polytechnique Fédérale de Lausanne (EPFL). In 1992, cadwork expanded outside the Swiss market by opening cadwork Germany in Hildesheim.
1980, the initial developers envisioned cadwork as a tool for the watch industry; developed by the Centre suisse d'électronique et de microtechnique (CSEM).
1982, the École Polytechnique Fédérale de Lausanne (EPFL) continued developing cadwork in Fortran and compiled in 32 or 64 bits on workstations, such as those from Apollo Computer, Digital Equipment Corporation (VAX and Alpha platforms), and Hewlett-Packard.
1989, Cadwork informatik was founded as a Swiss society in Basel, Switzerland.
1992, cadwork informatik Software GmbH, founded in Hildesheim.
1996, cadwork dropped support for workstations and became Microsoft Windows compliant.
2004, cadwork started the development of Lexocad.
2016, cadwork France Sàrl was founded in the East of France.
Recognition of industry practitioners
The ‘cadwork competition' provides recognition for aesthetically pleasing timber construction. There are various categories; in 2019, Laminated Timber Solutions received a public buildings award for their Molenbeek-Saint-Jean passive building constructed entirely of cross-laminated timber (CLT). This residential structure consists of 17 units (single- and dual-story apartments) with ancillary common parts.
See also
Virtual design and construction
Industry Foundation Classes (IFC)
Open Design Alliance (OpenDWG)
3D ACIS Modeler (ACIS)
Construction management
Construction engineering
References
Timber framing
Building information modeling
Computer-aided design software
3D graphics software
Computer-aided design software for Windows
Software companies of Switzerland | Cadwork informatik AG | [
"Technology",
"Engineering"
] | 1,523 | [
"Structural system",
"Building information modeling",
"Timber framing",
"Building engineering"
] |
61,511,546 | https://en.wikipedia.org/wiki/C29H31NO7 | {{DISPLAYTITLE:C29H31NO7}}
The molecular formula C29H31NO7 (molar mass: 505.56 g/mol, exact mass: 505.2101 u) may refer to:
Hernandaline
Rocaglamide | C29H31NO7 | [
"Chemistry"
] | 59 | [
"Isomerism",
"Set index articles on molecular formulas"
] |
61,512,316 | https://en.wikipedia.org/wiki/Bailout%20embedding | In the theory of dynamical systems, a bailout embedding is a system defined as
Here the function k(x) < 0 on a set of unwanted orbits; otherwise k(x) > 0. The trajectories of the full system of a bailout embedding bail out—that is, detach—from the embedding, into a larger space, in which they move around. If, after some time these orbits arrive at a stable neighbourhood of the embedding, k(x) > 0, they collapse once more onto the embedding; that is, onto the original dynamics. The bailout embedding forms in this way an enlarged version of the dynamical system, one in which particular sets of orbits are cut from the asymptotic or limit set, while maintaining the dynamics of a different set of orbits—the wanted set—as attractors of the larger dynamical system. With a choice of k(x) = −(γ + ∇f), these dynamics are seen to detach from unstable regions such as saddle points in conservative systems.
One important application of the bailout embedding concept is to divergence-free flows; the most important class of these are Hamiltonian systems.
References
Dynamical systems
Nonlinear systems | Bailout embedding | [
"Physics",
"Mathematics"
] | 264 | [
"Nonlinear systems",
"Mechanics",
"Dynamical systems"
] |
61,512,453 | https://en.wikipedia.org/wiki/C6H16N2 | {{DISPLAYTITLE:C6H16N2}}
The molecular formula C6H16N2 (molar mass: 116.21 g/mol, exact mass: 116.1313 u) may refer to:
Hexamethylenediamine
Tetramethylethylenediamine (TMEDA or TEMED) | C6H16N2 | [
"Chemistry"
] | 75 | [
"Isomerism",
"Set index articles on molecular formulas"
] |
61,512,943 | https://en.wikipedia.org/wiki/Geoff%20Malcolm | Geoffrey Norman Malcolm (23 April 1931 – 11 August 2019) was a New Zealand physical chemist. Appointed in 1969, he was the first chemistry professor at Massey University.
Biography
Born in Feilding on 23 April 1931, Malcolm was educated at Feilding Agricultural High School. He then studied at Canterbury University College, graduating Master of Science with first-class honours in 1954. He was awarded an 1851 Exhibition Memorial Scholarship, and completed doctoral studies at the University of Manchester in 1956.
In 1958, Malcolm married Sheila Mary Wilson, and the couple went on to have four children.
After a short period as an assistant lecturer at the University of Manchester in 1956–57, Malcolm returned to New Zealand. He was appointed as a lecturer in chemistry at the University of Otago in 1958, rising to the rank of reader. In 1969, he was appointed as professor of physical chemistry at Massey University, and was the first professor of chemistry at that institution. He later served as dean of science from 1984 to 1994. Following his retirement in 1995, he was conferred the title of professor emeritus. Malcolm was elected a Fellow of the New Zealand Institute of Chemistry (NZIC) in 1966, and served as president of the NZIC in 1977.
Malcolm died in Palmerston North on 11 August 2019.
References
1931 births
2019 deaths
People from Feilding
People educated at Feilding High School
University of Canterbury alumni
Alumni of the University of Manchester
New Zealand chemists
Physical chemists
Academic staff of Massey University
Academics of the University of Manchester
Fellows of the New Zealand Institute of Chemistry | Geoff Malcolm | [
"Chemistry"
] | 308 | [
"Physical chemists"
] |
61,513,349 | https://en.wikipedia.org/wiki/CONUS-Experiment | CONUS (COherent Neutrino nUcleus Scattering) Experiment is a research project at the commercial nuclear power plant in Brokdorf, Germany (see Figure 1). The CONUS project is sponsored by the Max-Planck-Institut für Kernphysik and Preussen Elektra GmbH.
The CONUS project is searching for the fundamental process of coherent elastic scattering of neutrinos off atomic nuclei. The primary goal is to confirm the existence of this process and to use this interaction type to investigate further neutrino properties within and beyond the standard model of elementary particle physics.
Science Principles and Motivation - Coherent Elastic Neutrino Nucleus Scattering
As electrically neutral leptons, neutrinos only interact via the weak force with other particles. Due to this fact, neutrino detectors are generally very large and filled with several (kilo)tons of target material.
There are basically two possibilities to detect neutrinos: First, they can interact with the electrons in the atomic shell of a target atom, and second they can interact with the protons and neutrons of an atomic nucleus. Interactions between neutrinos and electrons as well as neutrinos and nuclear constituents have already been well studied.
However, at low energies up to a maximum of a few tens of mega-electronvolt (MeV), neutrinos can interact coherently with the nucleus as a whole (see Figure 2). This process was predicted in 1974 and is known as coherent elastic neutrino nucleus scattering (CEυNS, pronounced "sevens"). Although its cross section is several magnitudes larger than the cross section of the conventionally used interaction channels (see Figure 3), the tiny recoil of the struck nucleus leads to a very low energy release, making the process very hard to detect. Therefore, experiments investigating this process need detectors with an extremely low energy threshold, i.e., below 1 kilo-electronvolt (keV). On the other hand, since the CEυNS interaction cross sections is enhanced, a few kilogram of detector material can already be enough to detect the interaction.
As the first experiment worldwide, the COHERENT experiment was able to experimentally prove the existence of coherent elastic neutrino nucleus scattering in 2017. Herein, it used a relatively high energy neutrino beam in comparison with reactor neutrinos. Further complementary studies at lower energies in the fully coherent regime are yet to come. Examining this low energy neutrino region is the main goal of the CONUS project.
Detector
Site
The detection as well as detailed investigations of the properties of CEυNS utilizing neutrinos from a nuclear reactor require the detector to be located as close as possible to the reactor core to guarantee a maximized neutrino flux. To achieve this, the CONUS detector is located at a distance of 17 m from the reactor core inside the nuclear reactor facility at Brokdorf, see Figure 4. This is only possible due to the selected detector technology such that it can be placed inside the facility without interfering with the operation of the reactor.
The Brokdoft reactor runs at a maximum thermal power of 3.9 GW, making it one of the most powerful in the world. On average, about 7.2 neutrinos are produced per nuclear fission (6 from fission products and 1.2 due to decays after neutron captures on Uranium-238). At the detector site this results in a flux of about 23 trillion neutrinos per second and square centimeter.
Detectors and Measurement
The CONUS Collaboration is using four highly pure germanium semiconductor detectors, each weighing 1 kg (see Figure 5).
If a neutrino originating from the reactor core scatters off a germanium nucleus, the small recoil energy of the nucleus is partially converted into ionization energy and partially into dissipation heat. Only the first energy part contributes to electrical signal formation in the ionisation detectors as used in CONUS. The dissipation phenomenon is known as quenching and is typically described by the Lindhard theory. Thus, a precise knowledge of this quenching factor is crucial, since its uncertainty is one of the main systematics of the experiment. To detect coherent elastic neutrino nucleus scattering, CONUS is collecting reactor-on and reactor-off data. By comparing these data, an excess of events in the expected energy window during reactor-on time can reveal the existence of CEυNS. In addition, measurements during reactor-off times allow for a precise determination of the background rate and its components. CONUS started collecting data on April 1, 2018, and has been continuously operated since then.
Shield
Although CEυNS is the neutrino interaction with the highest cross section, it still is a rare process. Moreover, since it comes with a very small energy and momentum transfer (<1 keV), a suitable detector needs to be shielded from any additional background. The three main background types and their mitigation strategies applied in CONUS are summarized here:
The relevant backgrounds can be put into 3 different categories:
Cosmic Radiation: Cosmic muons and muon-induced showers can interact with the target material of the detector in large quantities. Thus, cosmic radiation is one of the most relevant backgrounds. To suppress this type of background, many low background experiments are located deep underground. This is however not possible for CONUS; here the reactor building offers a modest overburden leading to a reduction of the muon flux by a factor of 2-3 only. To achieve an even better suppression of the muonic background, the CONUS detector is surrounded by an active muon veto system (see Figure 5). It consists of scintillator layers that can detect incoming muons crossing the detector setup. This way, the muon-induced background can be reduced approximately by a factor of 100.
Local Background: Besides cosmic radiation, there is also background coming from the direct surroundings. The most important contributions to the local background are naturally occurring radioactivity in the surroundings and neutrons radiated from the reactor core. To shield the detectors against this background, they are covered with several layers of lead (25 cm in total) as well as boron-doped polyethylene plates (see Figure 5). Another important background source that experiments (especially those located in a closed environment) have to deal with is the radioactive decay of airborne radon. Radon is an inert gas and can therefore leak through tiniest gaps of the shield layers and decay close to the detectors. To solve this problem, the detector chamber is continuously flushed with radon-free air from compressed air bottles.
Intrinsic Radioactivity: The detectors also contain small concentrations of radioactive isotopes. Hence, it is necessary to minimize the amount of radioactive impurities inside the detector. To achieve this goal, the materials used to build the detector were carefully analyzed with the help of the GIOVE detector at the underground laboratory of the Max-Planck-Institut für Kernphysik and selected correspondingly.
Despite the small volume of the CONUS setup of 1.6m^3, the massive high-density shield leads to a total mass of 11 tons.
Results
January 2021
In 2020, The CONUS project published first results on CEυNS using 3.73 kg of active detector material after almost 70 days of effective measurement time with the reactor turned on and about 16 days with the reactor turned off. With these data the until now most precise upper limit for the existence of the CEυNS process in the fully coherent regime could be determined. This limit constitutes valuable information for basic neutrino research, since it allows one to test predictions for the strength of CEυNS in the standard model theory or in variations of it. The unique performance of the CONUS detectors with their very low energy thresholds, ultra-low background levels and long-term stability is highlighted in Ref.
With additional data collected until and beyond the end of the reactor operation in late 2021, additional improvements of the data acquisition systems and a better understanding of the quenching factor in germanium, the sensitivity of the experiment is expected to improve significantly in the next few years.
January 20245
On January 9, 2025, a paper was published on the pre-print server Arχiv, announcing the possible first measurement of Coherent Elastic Neutrino-Nucleus Scattering (CEνNS) from reactor antineutrinos, which would be the first observation of the interaction in the full coherence regime. The paper only claims a statistical significance of 3.7σ (5σ is considered the standard for discovery in physics), and has not been peer-reviewed as of January 22, 2025.
Applications
Understanding the process of coherent elastic neutrino nucleus scattering may offer some possibilities in other areas, too.
It is generally expected that the coherent elastic neutrino nucleus scattering process plays a significant role in the dynamics of Core-Collapse Supernovae. Investigating this process will therefore help to better understand the dynamics of such stellar explosions. Furthermore a detailed study of coherent elastic neutrino nucleus scattering could potentially reveal some new physics beyond the standard model of particle physics. For instance, it could be used to study electromagnetic properties of neutrinos (e.g. neutrino magnetic moment), to investigate potential deviations of the weak mixing angle at low energies or to study possible non-standard interactions in the neutrino-quark sector.
Besides its fundamental importance for basic science, the detection of neutrinos via CEυNS offers some practical applications. One example is the possibility to use CONUS-like detectors for reactor monitoring.
External links
MPIK Division Lindner: CONUS
PreussenElektra GmbH: Brokdorf NPP
References
Particle physics facilities
Experimental particle physics
Research institutes in Germany | CONUS-Experiment | [
"Physics"
] | 2,002 | [
"Experimental physics",
"Particle physics",
"Experimental particle physics"
] |
61,513,402 | https://en.wikipedia.org/wiki/Entity%E2%80%93control%E2%80%93boundary | The entity–control–boundary (ECB), or entity–boundary–control (EBC), or boundary–control–entity (BCE) is an architectural pattern used in use-case–driven object-oriented programming that structures the classes composing high-level object-oriented source code according to their responsibilities in the use-case realization.
Origin and evolution
The entity–control–boundary approach finds its origin in Ivar Jacobson's use-case–driven object-oriented software engineering (OOSE) method published in 1992. It was originally called entity–interface–control (EIC) but very quickly the term "boundary" replaced "interface" in order to avoid the potential confusion with object-oriented programming language terminology.
It is further developed in the Unified Process, which promotes the use of ECB in the analysis and design activities with the support of UML stereotypes. Agile modelling and the ICONIX process elaborated on top of the ECB architecture pattern with robustness diagrams.
Principle
The ECB pattern organises the responsibilities of classes according to their role in the use-case realization:
an entity represents long-lived information relevant for the stakeholders (i.e. mostly derived from domain objects, usually persistent);
a boundary encapsulates interaction with external actors (users or external systems);
a control ensures the processing required for the execution of a use case and its business logic, and coordinates, sequences controls other objects involved in the use case.
The corresponding classes are then grouped into service packages, which are an indivisible set of related classes that can be used as software delivery units.
ECB classes are first identified when use cases are analyzed:
every use case is represented as a control class;
every different relation between a use case and an actor is represented as a boundary class;
entities are derived from the use-case narrative.
The classes are then refined and re-structured or reorganized as needed for the design, for example:
Factoring out common behaviors in different use-case controls
Identifying a central boundary class for each kind of human actor and for each external system that would provide a consistent interface to the outside world.
The ECB pattern assumes that the responsibilities of the classes is also reflected in the relations and interactions between the different categories of classes in order to ensure the robustness of the design.
Robustness diagram
Robustness diagrams allow to visually represent the relation between entities, controls, boundaries and actors. It uses graphical stereotypes introduced in Jacobson's early work:
The following robustness constraints apply:
Actors may only know and communicate with boundaries
Boundaries may communicate with actors and controls only.
Controls may know and communicate with boundaries and entities, and if needed other controls
Entities may only know about other entities but could communicate also with controls;
In principle entities should not know about boundaries and controls. In practice however, some variants allow entities, boundaries and controls to subscribe as observer to an entity.
Similarly, the constraint of a boundary class not knowing about other boundary classes only applies at the highest level, and not between classes that cooperate to implement the same boundary.
Relation to other architectural patterns
There is some similarity between ECB and model–view–controller (MVC): entities belong to the model, and views belongs to boundaries. However the role of the ECB-control is very different from MVC-controller, since it encapsulates also use-case business logic whereas the MVC controller processes user input which would be of the responsibility of the boundary in ECB. The ECB control increases separation of concerns in the architecture by encapsulating business logic that is not directly related to an entity.
The ECB can be used in conjunction with the hexagonal architecture, whenever the boundaries form the outer adapter layer.
ECB is compatible with the clean architecture which merges ECB principles with other architectural design paradigms. Clean architecture places entities at the core, and surround them with a use-case ring (i.e. ECB control) and a ring with gateways and presenters (i.e. ECB boundaries). However, clean architecture requires a one-way dependency from outside to inside, which requires to split ECB controls into use-case logic and object coordination.
See also
Architectural patterns
Use case
Unified process
Object-oriented analysis and design
Notes and references
Software design
Architectural pattern (computer science)
Object-oriented programming | Entity–control–boundary | [
"Engineering"
] | 886 | [
"Design",
"Software design"
] |
61,514,354 | https://en.wikipedia.org/wiki/Non-invasive%20micro-test%20technology | Non-invasive micro-test technology (NMT) is a scientific research technology used for measuring physiological events of intact biological samples. NMT is used for research in many biological areas such as gene function, plant physiology, biomedical research, and environmental science.
Most living things experience a constant exchange of ions and molecules with their surroundings as a result of biological processes. NMT uses specialized flux sensors, derived from microelectrodes, to measure this dynamic ion/molecule activity called flux around an intact sample. These fluxes reveal information about physiological phenomena.
Each NMT flux sensor is selective or specific for a particular ion/molecule of choice. Some of the more commonly published ion/molecule flux sensors are those that are commercially available, such as Ca2+, H+, K+, Na+, Cl−, Mg2+, Cd2+, NH4+, NO3−, Pb2+, Cu2+, O2, H2O2, and IAA (indole-3-acetic acid). Some other flux sensors include glutamate, glucose, Zn2+, Hg2+, and more that have been designed by individual laboratories.
NMT measures how much, how fast, and in what direction the chosen ions/molecules are moving. This is defined as diffusion flux, which is the amount of substance per unit area per unit time.
The principle of how NMT measures flux was described in the 1990s by a few different laboratories; Lionel Jaffe at the Marine Biological Laboratory described the Vibrating Probe technique, and Ian Newman at the University of Tasmania described the MIFE™ technique. There are also technologies SERIS and SIET that use this principle.
Basic procedure
Live sample preparation
Different samples need different amounts of preparation work. For example, small organisms, condensed organelles, and cultured cells, tissues, or organs can be measured with little alteration, but anything below the skin or surface of large organisms must be exposed in order to measure. Generally, once the sample is prepared so that the desired measurement site is revealed, NMT causes no further damage or interference with the test; because of this, NMT is most commonly used for measuring live, intact samples.
The live sample must be secured in a Petri dish so it does not move or shift. A single cell can be adhered by means such as a polylysine-coated slide; this also works for other small samples like condensed organelles. Large tissue samples like roots may be weighted down with filter paper and resin tiles. Plenty of other large samples can be measured as well, such as organs or whole small organisms like zebrafish.
Liquid media composition
The sample must be surrounded by liquid media, which will be different depending on the sample type, purpose of the test, and ions/molecules that will be measured. This media is a useful way to manipulate the sample's environment by adding things like drugs, stressors, or other biotic/abiotic stimuli.
This step can be the most challenging simply because it allows many possibilities for test manipulation. To get started in designing a specific new test, there is plenty of literature documenting successful composition of liquid media.
Recording
The prepared sample is placed under a microscope with a flux sensor which is controlled by a computer. The operator uses arrow keys to move the flux sensor to the desired point and distance from the sample, aided by a microscope camera.
The NMT flux sensor measures the flux and the data are plotted on-screen during the test. These fluxes are most often measured in the unit 10−12 moles • cm−2 • s−1, or sometimes as small as 10−15 moles • cm−2 • s−1, allowing flux to be measured from something as small as a single cell. During the test, further changes can be introduced like a stressor or other abiotic stimulus, and the flux patterns will change on-screen to show the physiological changes. For example, cold stress can be studied by adding ice-cold test buffer to the solution during testing.
Variations
1-dimensional
This is the most common NMT test in which the flux sensor is moved in one direction in reference to the sample, generally perpendicular to the sample boundaries.
2-dimensional
There is not much documented application of 2-dimensional measurement in NMT; the possibility was demonstrated with the Vibrating Probe technique by Degenhardt et al in 1998. They moved the flux sensor both perpendicular and then parallel to a plant root, then summed up the flux vectors to generate the 2-dimensional flux direction. In this kind of manner, NMT can measure 2D fluxes as well, using the same software that measures 3D fluxes.
3-dimensional
One of the pioneers of 3D ion/molecule flux mapping is Joseph Kunkel. To generate a 3-dimensional view of fluxes, the flux sensor must take measurements in the X, Y, and Z directions at each point around a sample. In 2006, a view of H+ and O2 3D flux vectors around a pollen tube was produced using Mageflux software developed by Yue Xu.
Simultaneous
NMT flux sensors can be set up to measure two or more different ion/molecule fluxes at the same time, allowing the user to see the flux changes simultaneously, and to see the relationship between them. Combining two particular flux measurements simultaneously can be a strong indicator of physiological phenomena. For example, measuring both H+ and O2 simultaneously from a tumor sample (see figure to the right) can provide significant information about cancer metabolism that is far more useful than measuring only one at a time.
Applications
Genetics
It is widely accepted that both intracellular and extracellular ionic and molecular activities are vital to many physiological processes, also making them useful indicators of gene functions. By measuring dynamic ion/molecule fluxes, NMT has helped research on genes related to factors such as cold stress, salt tolerance, cadmium uptake, and nutrient uptake in plants. In biomedical genetic research, NMT has measured samples such as liver cells to investigate gene expression through fluxes.
Plant biology
NMT has been widely applied in plant biology in fields such as abiotic/biotic stress, plant nutrition, plant growth and development, plant/microbe interaction, plant defense, photosynthesis, signal transduction research, and more. Roots are commonly measured, in addition to many other plant samples such as leaf tissue, root hairs, guard cells, salt gland cells, mesophyll cells, and condensed organelles like chloroplasts and vacuoles.
NMT can help identify plants that are more resistant to stressors like salt, temperature, drought, and disease. It is also a useful tool for studying plant nutrition absorption and regulation mechanisms in ways such as monitoring rates of nutrient uptake at the root surface.
Biomedical
NMT is applied in biomedical research in various fields such as neuroscience, tumor research, drug screening, metabolism, and bone research.
NMT is a useful tool for evaluating the effects of treatments for diseases like diabetes and cancer in tissue samples, as it can measure the flux changes in response to treatments. Measured samples include tumor tissue, neurons, brain tissue, liver cells, bone, muscle, and many more. Metabolism rates can be measured by NMT using O2 and H+ fluxes. In bone research, the flux of Ca2+ measured by NMT helps research on bone healing and growth.
Environmental
Various areas of environmental research in which NMT has been applied include water pollution detection, biological early warning, water quality assessment, and heavy metal detection.
With global heavy metal pollution of crops on the rise, more NMT heavy metal flux sensors such as Cd2+, Cu2+, and Pb2+ have been used in research to identify plants that can tackle this problem with phytoremediation.
For water quality and pollution research, water plants and algae have been measured, as well as biofilms and fish embryos.
See also
Fick's laws of diffusion
Nernst equation
Bioelectronics
Patch clamp
Diffusion
Scanning vibrating electrode technique
Microelectrode
References
Biological techniques and tools | Non-invasive micro-test technology | [
"Biology"
] | 1,649 | [
"nan"
] |
61,514,431 | https://en.wikipedia.org/wiki/Lactarius%20acris | Lactarius acris is a member of the large milk-cap genus Lactarius in the order Russulales. Found in Europe, the species was described in 1821 by British botanist Samuel Frederick Gray. It is considered unpalatable due to its strong flavour, but the bitterness can be removed by repeated washing and salting.
Description
This is the only species in the Lactarius genus whose milk turns pink after a few moments of exposure to air. The cap has between 5 and 8 cm in diameter and is chestnut brown and becomes sticky when wet.
See also
List of Lactarius species
References
External links
acris
Fungi described in 1821
Fungi of Europe
Fungus species | Lactarius acris | [
"Biology"
] | 136 | [
"Fungi",
"Fungus species"
] |
61,514,499 | https://en.wikipedia.org/wiki/C23H32O4S | {{DISPLAYTITLE:C23H32O4S}}
The molecular formula C23H32O4S (molar mass: 404.563 g/mol) may refer to:
6β-Hydroxy-7α-thiomethylspironolactone
7α-Thiomethylspironolactone sulfoxide
Molecular formulas | C23H32O4S | [
"Physics",
"Chemistry"
] | 82 | [
"Molecules",
"Set index articles on molecular formulas",
"Isomerism",
"Molecular formulas",
"Matter"
] |
61,514,527 | https://en.wikipedia.org/wiki/C25H42N7O18P3S | {{DISPLAYTITLE:C25H42N7O18P3S}}
The molecular formula C25H42N7O18P3S (molar mass: 853.623 g/mol) may refer to:
Beta-Hydroxybutyryl-CoA
3-Hydroxyisobutyryl-CoA | C25H42N7O18P3S | [
"Chemistry"
] | 73 | [
"Isomerism",
"Set index articles on molecular formulas"
] |
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