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70,685,311 | https://en.wikipedia.org/wiki/Mean%20line%20segment%20length | In geometry, the mean line segment length is the average length of a line segment connecting two points chosen uniformly at random in a given shape. In other words, it is the expected Euclidean distance between two random points, where each point in the shape is equally likely to be chosen.
Even for simple shapes such as a square or a triangle, solving for the exact value of their mean line segment lengths can be difficult because their closed-form expressions can get quite complicated. As an example, consider the following question:
What is the average distance between two randomly chosen points inside a square with side length 1?
While the question may seem simple, it has a fairly complicated answer; the exact value for this is .
Formal definition
The mean line segment length for an n-dimensional shape S may formally be defined as the expected Euclidean distance ||⋅|| between two random points x and y,
where λ is the n-dimensional Lebesgue measure.
For the two-dimensional case, this is defined using the distance formula for two points (x1, y1) and (x2, y2)
Approximation methods
Since computing the mean line segment length involves calculating multidimensional integrals, various methods for numerical integration can be used to approximate this value for any shape.
One such method is the Monte Carlo method. To approximate the mean line segment length of a given shape, two points are randomly chosen in its interior and the distance is measured. After several repetitions of these steps, the average of these distances will eventually converge to the true value.
These methods can only give an approximation; they cannot be used to determine its exact value.
Formulas
Line segment
For a line segment of length , the average distance between two points is .
Triangle
For a triangle with side lengths , , and , the average distance between two points in its interior is given by the formula
where is the semiperimeter, and denotes .
For an equilateral triangle with side length a, this is equal to
Square and rectangles
The average distance between two points inside a square with side length s is
More generally, the mean line segment length of a rectangle with side lengths l and w is
where is the length of the rectangle's diagonal.
If the two points are instead chosen to be on different sides of the square, the average distance is given by
Cube and hypercubes
The average distance between points inside an n-dimensional unit hypercube is denoted as , and is given as
The first two values, and , refer to the unit line segment and unit square respectively.
For the three-dimensional case, the mean line segment length of a unit cube is also known as Robbins constant, named after David P. Robbins. This constant has a closed form,
Its numerical value is approximately
Andersson et. al. (1976) showed that satisfies the bounds
Choosing points from two different faces of the unit cube also gives a result with a closed form, given by,
Circle and sphere
The average chord length between points on the circumference of a circle of radius r is
And picking points on the surface of a sphere with radius r is
Disks
The average distance between points inside a disk of radius r is
The values for a half disk and quarter disk are also known.
For a half disk of radius 1:
For a quarter disk of radius 1:
Balls
For a three-dimensional ball, this is
More generally, the mean line segment length of an n-ball is
where depends on the parity of ,
General bounds
Burgstaller and Pillichshammer (2008) showed that for a compact subset of the n-dimensional Euclidean space with diameter 1, its mean line segment length L satisfies
where denotes the gamma function. For n = 2, a stronger bound exists.
References
External links
Length
Probability problems | Mean line segment length | [
"Physics",
"Mathematics"
] | 767 | [
"Scalar physical quantities",
"Physical quantities",
"Distance",
"Quantity",
"Size",
"Probability problems",
"Length",
"Wikipedia categories named after physical quantities",
"Mathematical problems"
] |
70,687,905 | https://en.wikipedia.org/wiki/Anonymous%20and%20the%20Russian%20invasion%20of%20Ukraine | Anonymous, a decentralized international activist and hacktivist collective, has conducted numerous cyber-operations against Russia since February 2022 when the Russian invasion of Ukraine began.
Prelude
Starting from late 2021, Anonymous took notice of the military build-up near the Russia–Ukraine border and thus acted to propagate peace plans to end the war in Donbas by defacing various websites, such as United Nations' Networks on Migration, Polar Research Institute of China, Convention on Biological Diversity, and various government websites in China.
In the hacking campaign named "Operation Samantha Smith", which is a reference to the 1980s child peace activist, they called for a referendum in Ukraine on whether to presumably follow the now-defunct Minsk Protocol or hand over the separatist-controlled territories to a UN peacekeeping administration. Later, a second referendum in the separatist regions would then ask voters to choose to reunite with Ukraine, gain independence, or join Russia. Besides that, they also called for the creation of a "neutral grouping" of countries "wedged between NATO and Russia" that would include Ukraine, Finland, Belarus, Georgia, Armenia, Azerbaijan, and Moldova. Anonymous argued that the so-called "neutral security belt" could serve as an alliance similar to the North Atlantic Treaty Organization (NATO) or the Collective Security Treaty Organization (CSTO) that acts as a cordon sanitaire between NATO and CSTO countries in order to "assuage Russia's fears without NATO losing its face."
As the situation escalated, they threatened to take hostage of industrial control systems and implicitly warned Russia that the "sole party to be blamed if we escalate on that, will be the same one who started it in the very first place with troop buildups, childish threats, and waves of unreasonable ultimatums." Furthermore, they urged the United Nations to immediately deploy peacekeepers on "at least the Ukrainian side of the frontline in Donbass" under the basis of UN Resolution 337 (V) to "prevent any further provocations" by any side.
In the aftermath of Russia's recognition of the Donetsk People's Republic and the Luhansk People's Republic and in accordance to the hacking collective's threats to take hostage of industrial control systems, they conducted a small hack on a Russian Modbus device which they've announced on a hacked Chinese cultural website, although early on Anonymous kept the location of the hack ambiguous.
According to Anonymous, the Modbus device was said to be a Schneider Electric's Modicon M251 logic controller, and that they were previously "playing nice" so not to give Russia a casus belli but because of the subsequent Russian invasion of Ukraine, Operation Samantha Smith was presumably deemed as a failure and Anonymous would start attacking Russian websites and systems as retaliation.
Operation Russia
On February 25, 2022, Twitter accounts associated with Anonymous declared that they had launched a 'cyber operation' against the Russian Federation, in retaliation for the invasion of Ukraine ordered by Russian president Vladimir Putin. The operation was dubbed "OpRussia". The group later temporarily disabled websites such as RT.com and the website of the Defence Ministry along with other state owned websites. Anonymous also leaked 200 GB worth of emails from the Belarusian weapons manufacturer Tetraedr, which provided logistical support for Russia in the Russian invasion of Ukraine. Anonymous also hacked into Russian TV channels and played Ukrainian music through them and showed uncensored news of what was happening in Ukraine.
They hacked into a Russian Center for the Protection of Monuments website (memorials.tomsk.ru) and uploaded three defacement pages adorned with the blue and yellow colors of the Ukrainian flag. In the first defacement page, they included the standard Anonymous logo, a music video of Mandopop song "Fragile", brief announcement that the Operation Samantha Smith has morphed into Operation Russia and Operation Ukraine while warned "we will do what we must" following the Russian military invasion, and a photo of Ukrainian revolutionary Nestor Makhno.
Following through their threats during Operation Samantha Smith, Anonymous had also hacked a Chinese SIMATIC programmable logic controller along with two Russian Modbus devices. Memes from social-networking website Reddit appeared on the defaced website, including an image of Russian President Vladimir Putin in heavy makeup with a rainbow as a background, together with a series of embedded Reddit posts which asked users to vote for which parts of Russia should declare independence. Next, appearing on the hacked website are the Ukrainian national anthem, Ukrainian coat of arms and a map appearing to show Kuomintang plans for an invasion of China and the Soviet Union.
In the second defacement page uploaded by Anonymous to memorials.tomsk.ru, the photos and the names of deceased passengers from Malaysia Airlines Flight 17 were shown, while in the third defacement page, the Anonymous logo, the Guy Fawkes mask image, and a video that plays the circus theme song "Entrance of the Gladiators" on loop for 10 hours appeared. In an interview, the spokesperson of the hacking collective emphasized that "Anonymous is not a group, not a country, but an amorphous idea. It flows like air, like water, like everything. Let it be known that since its inception, Anonymous never have restrictions that say that only homo sapiens can be part of it.", while threatening that any further cyberattacks will be "precipitated by Russia's continued failure in recognizing the territorial aggression in itself is nothing but a relic of dark ages in the distant past."
Besides posting Ukrainian president Volodymyr Zelenskyy's defiant speech against the invasion and a video calling for the creation of neutral grouping of countries between NATO and Russia into memorials.tomsk.ru, Anonymous announced that they had hacked a Russian Linux terminal and a gas control system in North Ossetia, while stating that they had almost caused an explosion in the latter, but did not because of a fast-acting human worker. The hacking collective also added several hashtags and slogans, including "SlavaUkraini", "#OpRussia", "Putin #EpikFail", and "/r/opukraine" into the gas control system.
Anonymous is also believed to be responsible for hacking several Russian state TV channels; many users on Twitter and TikTok uploaded videos showing channels playing Ukrainian music and displaying pro-Ukraine images, flags, and symbols. Furthermore, they had hacked Russian television services in order to broadcast footage of the war in Ukraine, and systems believed to be related to Russian space agency Roscosmos where they defaced its website and leaked mission files.
A yacht allegedly belonging to Vladimir Putin was reportedly hacked by the group where they changed its call sign to “FCKPTN” and setting its target destination to “hell”. Furthermore, they broadcast a troll face picture through a hacked Russian military radio.
At least 2,500 Russian and Belarusian targets were reportedly hacked by Anonymous. These included more than three hundred websites of Russian government agencies, state media outlets, banks, as well as websites of leading Belarusian banks such as Belarusbank, Priorbank and Belinvestbank. Furthermore, they also hacked a website belonging to Chechnya's regional government. They also warned that “If things continue as they have been in the past few days, the cyber war will be expanded and our measures will be massively increased. This is the final warning to the entire Russian government. Don't mess with Anonymous.”
Over 400 Russian cameras were hacked by Anonymous with anti-Putin messages such as "Putin is killing children". Some of the cameras had its live feeds compiled onto a website called behindenemylines.live. On the website, Anonymous explains that the hacks are a message to Russia that it must "pay a huge price because of the shameful decision of the dictator Putin to attack an independent Ukraine by armed forces." It asserted that sanctions imposed on Russia will result in state collapse and have worse consequences for its citizens than the oligarchy. Anonymous further stated that "150 million Russians do not know the truth about the causes or course of the war in Ukraine" and are instead fed a steady stream of "Kremlin propaganda." Anonymous stated that the purposes of the hacks are to "spread information to the Russian people" as well as serve as a possible reconnaissance tool for Ukraine. It then directly addressed Russians: "we just want you to know that you are being brainwashed by state propaganda, and the Kremlin and Putin are lying to you." Besides that, they emphasized that "Ukraine is not controlled by Nazis" and hence the Ukrainian people "do not need you to 'free' them." while calling for a popular uprising, vowing that they will receive support from the rest of the world.
In response to the seizure of Ukraine's Zaporizhia Nuclear Power Plant by Russia, Anonymous defaced the website of Rosatom and gained access to gigabytes of data which they intended to leak publicly. Furthermore, they had hacked into printers in Russia to spread anti-propaganda messages.
In the aftermath of Bucha massacre, the hacking collective leaked the personal information of 120,000 Russian soldiers in Ukraine.
Hacks
On March 7, 2022, Anonymous actors DepaixPorteur and TheWarriorPoetz declared on Twitter that they hacked 400 Russian surveillance cameras and broadcast them on a website. They call this operation "Russian Camera Dump".
On March 10, 2022, Anonymous claimed responsibility for the theft and publication of 820 GB worth of documents from Roskomnadzor. It is being released by Distributed Denial of Secrets (DDoSecrets). DDoSecrets writes about the leak: "This dataset was released in the buildup to, in the midst of, or in the aftermath of a cyberwar or hybrid war. Therefore, there is an increased chance of malware, ulterior motives and altered or implanted data, or false flags/fake personas. As a result, we encourage readers, researchers and journalists to take additional care with the data." The leak revealed a new online surveillance system tracking anti-war sentiment and other "threats" to Russian stability and the Putin regime.
On March 25, 2022, DDoSecrets published approximately 22.5 gigabytes of emails allegedly from the Central Bank of Russia, which was allegedly hacked by Anonymous actor Thblckrbbtworld.
On March 29, 2022, DDoSecrets published 2.4 gigabytes of emails from RostProekt, which was hacked by Anonymous actor DepaixPorteur. RostProekt is a Russian construction company. The RostProekt hack was dubbed as a "celebration" for the grand opening of the now-defunct AnonymousLeaks, a leak site solely for leaks from the Anonymous Collective.
On April 1, 2022, DDoSecrets published approximately 79,000 emails from Transneft, which was hacked by Anonymous.
On April 2, 2022, DDoSecrets published approximately 200,000 emails from Capital Legal Services, which was hacked by Anonymous actor Wh1t3Sh4d0w.
On April 4, 2022, DDoSecrets published more than 900,000 emails from the All-Russia State Television and Radio Broadcasting Company (VGTRK), which were hacked by the Anonymous aligned NB65.
On April 7, 2022, DDoSecrets published approximately 100,000 emails from Aerogas, which was hacked by Anonymous.
On April 11, 2022, DDoSecrets published approximately 230,000 emails from Blagoveshchensk City Administration, which was hacked by Anonymous.
On April 12, 2022 Anonymous leaked 446 GB of data from Russian Ministry of Culture.
On April 13, 2022, DDoSecrets published roughly 495,000 emails from Technotec, which was hacked by the Anonymous.
On April 15, 2022, DDoSecrets published roughly 400 gigabytes of emails from the Continent Express, a Russian travel agency, which was hacked by the Anonymous aligned NB65.
On April 18, 2022, DDoSecrets published 222 gigabytes of emails, files and decryption keys from Gazregion, which was hacked by three different sources around the same time, including the Anonymous actor DepaixPorteur, the Anonymous affiliated NB65, and an unnamed actor.
On April 19, 2022, DDoSecrets published 15,600 emails from GUOV i GS – General Dept. of Troops and Civil Construction, which was hacked by the Anonymous actor DepaixPorteur.
On April 20, 2022, DDoSecrets published 250,000 emails from Worldwide Invest, which was hacked by Anonymous.
On April 20, 2022, DDoSecrets published 426,000 emails from Worldwide Invest, which was hacked by Anonymous.
On April 22, 2022, DDoSecrets published 365,000 emails from Accent Capital, which was hacked by Anonymous.
On April 25, 2022, DDoSecrets published nearly 1,100,000 emails from ALET/АЛЕТ, which was hacked by Anonymous.
On May 5, 2022, DDoSecrets published roughly 480 gigabytes of files, emails and disk images from CorpMSP, which was hacked by the Anonymous aligned NB65.
On May 9, 2022, which is the Victory Day in Russia, the video-hosting website RuTube was taken down through cyberattacks, which Anonymous had claimed responsibility later. Furthermore, Network Battalion 65 (NB65), a hacktivist group affiliated with Anonymous, has reportedly hacked Russian payment processor Qiwi. A total of 10.5 terabytes of data including transaction records and customers' credit cards had been exfiltrated. They further infected Qiwi with ransomwares and threatened to release more customer records.
On May 11, 2022, DDoSecrets published over 466 gigabytes of emails from the Nikolai M. Knipovich Polar Research Institute of Marine Fisheries and Oceanography (PINRO), which was hacked by Anonymous actors DepaixPorteur and B00daMooda.
On May 12, 2022, DDoSecrets published over 7,000 emails from the Achinsk City Government, which was hacked by Anonymous.
On May 13, 2022, DDoSecrets published 116,500 emails from SOCAR Energoresource, which was hacked by Anonymous.
On May 30, 2022, DDoSecrets published more than 184 gigabytes of emails from Metprom Group LLC, which was hacked by the Anonymous actors DepaixPorteur, B00daMooda, and Wh1t3Sh4d0w.
On June 1, 2022, DDoSecrets published more than 1,000,000 emails from Vyberi Radio, which was hacked by Anonymous.
On June 3, 2022, DDoSecrets published 1 terabyte of data, which included millions of files including emails, court files, client data, classified data, photographs, videos, payment information, and more from Rustam Kurmaev and Partners (RKPLaw), which was hacked by Anonymous actors DepaixPorteur and B00daMooda.
On September 1, 2022, Russian taxi service Yandex Taxi was hacked which sent dozens of cars to a location resulting in a traffic jam that lasted up to three hours. Anonymous claimed responsibility for the hack shortly thereafter.
See also
Russo-Ukrainian War
2022 Russian invasion of Ukraine
Russo-Ukrainian War
2021–2022 Russo-Ukrainian crisis
Cyberwar
Cyberwarfare
Fourth-generation warfare
Information warfare
Internet security
2022 Ukraine cyberattacks
Activism
Electronic civil disobedience
Leaderless resistance
Streisand effect
Other related articles
Anti-mask laws
Derp (hacker group)
LulzRaft
Securax
RedHack
We Are Legion: The Story of the Hacktivists
References
Russian invasion of Ukraine
Cyberattacks
Information society
Internet-based activism
Internet culture
Internet memes
Internet trolling
Internet vigilantism
Hacking in the 2020s
Reactions to the Russian invasion of Ukraine
Distributed Denial of Secrets | Anonymous and the Russian invasion of Ukraine | [
"Technology"
] | 3,332 | [
"Computing and society",
"Information society"
] |
70,687,909 | https://en.wikipedia.org/wiki/Neodymium%20arsenate | Neodymium arsenate, also known as neodymium(III) arsenate, is the arsenate of neodymium with the chemical formula of NdAsO4. In this compound, neodymium exhibits the +3 oxidation state. It has good thermal stability, and its pKsp,c is 21.86±0.11.
Preparation
Neodymium arsenate can be obtained from the reaction between sodium arsenate (Na3AsO4) and neodymium chloride (NdCl3) in solution:
Na3AsO4 + NdCl3 → 3 NaCl + NdAsO4↓
When crystallizing from a lead pyroarsenate flux, neodymium arsenate crystals produced explode when cooled.
Neodymium arsenate also occurs in nature as a mineral.
See also
Arsenic
References
Neodymium(III) compounds
Arsenates | Neodymium arsenate | [
"Chemistry"
] | 190 | [
"Inorganic compounds",
"Inorganic compound stubs"
] |
70,688,199 | https://en.wikipedia.org/wiki/Candida%20catenulata | Candida catenulata is a yeast-form fungus in the phylum Ascomycota. It is distributed globally and commonly found on the skin of humans and animals, in soil, and in dairy products.
Taxonomy
C. catenulata is a species originally assigned to the genus Candida. To be a species in the genus Candida implies a close relatedness to the type species Candida tropicalis, but it was found through tRNA, rRNA, and other phylogenetic analysis that C. catenulata is not closely related to C. tropicalis. As such, C. catenulata has been reclassified into a new genus, Diutina, as Diutina catenulata. This change also affected the family classification as Diutina is in the family Debaryomycetaceae/Metschnikowiaceae while the original genus Candida belongs to the family Saccaromycetaceae. Its membership to phylum Ascomycota, class Saccharomycetes, and order Saccharomycetales have remained unchanged.
Morphology
C. catenulata is capable of living both as a yeast or as a pseudomycelium composed of pseudohyphae and capsule-shaped cells with dimensions of 1-2 micrometers by 5-7 micrometers.
Ecology
Candida catenulata is a skin and gut microbiome component of humans and animals, soil microbiome fungi, dairy product contaminant, and occasional opportunistic fungal pathogen. In the soil C. catenulata is most strongly associated with the necrobiome soil community. In soils surrounding cadavers, C. catenulata populations have been observed in experiments to grow to compose a significant portion of these soil communities over time. In cases of C. catenulata operating as an opportunistic pathogen it is most common that infections manifest as some type of superficial skin infection. In a rare case a 42-year-old woman in Strasbourg, France was found to be invasively infected by Candida catenulata after blood cultures were prepared upon her re-admittance to a hospital post cancer treatment. This is the only recorded case of invasive infection by C. catenulata.
Bioremediation
In a lab setting when supplied with food waste and composting, diesel fuel-inoculated colonies of C. catenulata were observed to degrade approximately 80% of petroleum hydrocarbons present in their environment. In un-inoculated colonies 48% hydrocarbon degradation was observed. Both of these results indicate C. catenulata is a promising species for use in bioremediation efforts of oil contaminated environments.
References
catenulata
Yeasts
Fungal pathogens of humans
Fungus species | Candida catenulata | [
"Biology"
] | 564 | [
"Yeasts",
"Fungi",
"Fungus species"
] |
70,688,323 | https://en.wikipedia.org/wiki/Auricularia%20mesenterica | Auricularia mesenterica, commonly known as the tripe fungus, is a species of fungus in the family Auriculariaceae. Basidiocarps (fruit bodies) are gelatinous and typically formed in coalescing tiers on stumps and logs. They are partly pileate, with hirsute, zoned caps, and partly resupinate, with smooth to wrinkled undersurfaces that spread over the wood. Auricularia mesenterica is a saprotroph on dead deciduous trees and shrubs. The species is restricted to Europe and Central Asia.
Taxonomy and etymology
Auricularia mesenterica was described from England in 1785 by James Dickson as Helvella mesenterica and transferred to the genus Auricularia by Christiaan Hendrik Persoon in 1822. The species was considered to be cosmopolitan and was subsequently applied to collections from America, Asia, and Australia as well as Europe.
Molecular research, based on cladistic analysis of DNA sequences, has however shown that Auricularia mesenterica (as previously understood) is a complex of related species and that A. mesenterica sensu stricto is confined to Europe and Central Asia, with superficially similar but distinct species occurring elsewhere.
The specific epithet is a Latin adjective formed from the Ancient Greek word (mesentérion), "middle intestine", from (meso-, "middle, center") and (énteron, "intestine"), referring to its shape.
Description
This species forms bracket-like fruit bodies that first appear pale, rubbery, and button-like, expanding to typically across and hardening with age. The fruit bodies often merge into compound structures sometimes running along fallen trunks and branches for more than . The upper surface is grey to brown or buff, tomentose to hispid with concentric zones, while the underside is thickly gelatinous, irregularly folded radially and reddish brown. The spore print is white. Microscopically the basidia are auricularioid (tubular with three lateral septa) and the basidiospores are allantoid (sausage-shaped), 14 to 17 by 4.5 to 5 μm.
Distribution and habitat
Originally described from England, the species is known to occur throughout Europe and into Central Asia as far as Uzbekistan. Basidiocarps are formed on various deciduous tree stumps and logs.
Similar species
Other species in the Auricularia mesenterica complex include Auricularia brasiliensis in South America, A. pusio in Australia, A. africana in East Africa, and A. asiatica, A. orientalis, A. srilankensis, and A. submesenterica in Asia. Other species of Auricularia lack the zoned, hirsute upper surface found in the A. mesenterica complex. Some unrelated Stereum species may have similarly zoned caps, but their fruit bodies are leathery (not gelatinous) and their undersurfaces are often yellowish to orange.
Uses
Before the fruit body fully matures and hardens, young specimens are said to be edible, but in some local populations, these fungi tend to bioaccumulate high levels of heavy metals from their environment. A. mesenterica has shown to have high levels of phenols, flavonoids, and antioxidant activity, having potential as antitumor agent.
References
Auriculariales
Taxa named by James Dickson (botanist)
Fungi described in 1785
Fungi of Europe
Fungus species | Auricularia mesenterica | [
"Biology"
] | 746 | [
"Fungi",
"Fungus species"
] |
70,689,080 | https://en.wikipedia.org/wiki/Pullulan%20bioconjugate | Pullulan bioconjugates are systems that use pullulan as a scaffold to attach biological materials to, such as drugs. These systems can be used to enhance the delivery of drugs to specific environments or the mechanism of delivery. These systems can be used in order to deliver drugs in response to stimuli, create a more controlled and sustained release, and provide a more targeted delivery of certain drugs.
Pullulan formulation
Pullulan is generated by the microbial A. pullulans through the processing mainly of glucose, but can also be produced from maltose, fructose, galactose, sucrose, and mannose. In a commercial setting, pullulan is obtained from a strain of A. pullulans that is non-toxic, non-pathogenic, and unmodified genetically that is given a liquid form of starch in a set environment. The pullulan produced can be modified by different conditions such as the nutrients provided, temperature, pH, oxygen content, and other supplements. The microbial needs to be provided with a source of carbon and nitrogen in order to produce pullulan and the ratio of carbon to nitrogen needs to be precise in order to maximize pullulan production. Higher levels of nitrogen than carbon are required as excess carbon can decrease the efficiency of the enzymes and excess nitrogen can increase the production of biomass, but does not affect the pullulan production. Oxygen is also important for the proliferation of the A. pullulans cells and the production of pullulan. Further supplements can be used in order to increase the level of pullulan production, such as olive oil and tween 80.
While the manufacturing conditions of pullulan can be altered in order to increase yield, chemical modifications of pullulan can also be used to alter the properties of the pullulan. The unmodified structure of pullulan contains nine hydroxyl groups attached to the backbone of the molecule, and these hydroxyl groups can be replaced with other functional groups. Some examples of processes that can modify the functional groups of pullulan include sulfation, esterification, oxidation, etherification, copolymerization, amidification, and others. Pullulan can be given a negative charge through creating an ester linkage that attaches a carboxylate group to the hydroxyl, which yields a carboxymethyl pullulan. Pullulan is hydrophilic and can be modified to have hydrophobic functionality by adding a cholesterol group. The main benefit of the added hydrophobic functionality is that it makes it so the pullulan can form self assembling micelles. Another notable modification to pullulan is the acetylation of pullulan in order to create pullulan acetate (PA), which also has a hydrophobic functionality. PA has the benefit of forming self-assembled nanoparticles, which can simplify manufacturing of certain pullulan bioconjugates. Pullulan and pullulan derivatives can also be folated in order to improve cancer cell targeting as the nanoparticle can be endocytosed into the cancer cells through folate-mediated endocytosis.
Stimuli responsive systems
Pullulan bioconjugate systems can be formed to respond to many different stimuli to enhance the release of the drug to the target tissue. These stimuli include pH, temperature, photothermal, electrical, ultrasonic, magnetic, and enzymatic. The pH is often used to target tumor tissues, as the extracellular pH of tumors is more acidic than the normal cells.
A pullulan and polydopamine hydrogel loaded with crystal violet demonstrated pH responsive behavior due to the protonation of the polydopamine, which increased the release of the crystal violet in the acidic environment. The study showed that at a pH of a normal cell's extracellular environment, 7.4, about 60% of the crystal violet was released compared to the 87% release when in a pH of 5.0. The use of pH responsive systems for the treatment of cancer may aid in the ability to overcome resistance of the drug as well as prevent excess damage to healthy tissue.
Another pH responsive pullulan system was formed with pullulan and doxorubicin where the doxorubicin is attached to the pullulan by hydrazone bonds. The drug release of the doxorubicin was tested at two pHs, 7.4 and 5, where the hydrazine is stable at 7.4 and cleaves in acidic environments. The results from this study supported the results from the pullulan and polydopamine study, as doxorubicin was released faster in the acidic environment than the pH that reflected a normal cell's extracellular environment.
Temperature can also be used as a trigger to control the drug release from pullulan systems. Thermal responsive pullulan systems can be used in conjunction with thermal generating treatments for cancer in order to improve the treatment. Nanoparticles composed of periodate oxidized carboxymethyl pullulan crosslinked with two Jeffamines were synthesized and demonstrated that the nanoparticle size could be decreased with increased temperature. The nanoparticles decrease in size with increasing temperature due to the increased temperature promoting the hydrophobic interactions of the structure. Altering the temperature can induce heating or cooling dynamics that are reversible, which allows for unique properties in terms of drug release. Pullulan can be altered with photosensitizers in order to provide a controlled thermal reaction in a target area. Spiropyrane can be added to pullulan in order to act as a photosensitizer.
Electrical stimuli can be used to alter the delivery of drugs through pullulan constructs. A copolymer polyacrylamide-graft-pullulan was synthesized and used for transdermal delivery of rivastigmine tartarate. In this study, the use of electric stimuli demonstrated the ability to increase the diffusion rate and in a way acted as a controllable switch to control diffusion rate. Pullulan systems can be used to enhance ultrasound imaging, as pullulan-graft-poly(carboxybetaine methacrylate) demonstrated the ability to generate carbon dioxide in response to ultrasound, which enhanced the contrast. Superparamagnetic iron oxide nanoparticles (SPIONs) have been generated which have magnetic properties, which showed to improve uptake and also decrease the cytotoxicity. Enzymes can also be used to trigger drug release mechanisms, such as how esterase has been used to cleave photosensitizers from pullulan in order to increase the photodynamic reaction.
As demonstrated in the last example, these stimuli response mechanisms do not have to be independent. They can be used in combinations in order to improve the efficacy of the drug delivery.
Self-assembled pullulan mechanism
When pullulan is modified with a hydrophobic functionality, such as cholesterol, the pullulan derivative forms self-assembled vesicles that can encapsulate a hydrophobic drug. With the hydrophobic functional group, the pullulan derivative is an amphiphilic molecule, which when in an aqueous environment forms a micelle. This micelle has a hydrophilic exterior with the pullulan backbone and a hydrophobic core due to the functional group added to the pullulan. The nanoparticles formed are spherical, have an average size of 20-30 nanometers according to dynamic light scattering measurements, and are able to be maintained in physiological conditions. Cholesteryl-pullulan (CHP) is an example of a pullulan derivative that is capable of forming self-assembled mechanisms and has been used to anticancer drugs. The size of the self-assembled nanoparticle can be adjusted by changing the amount of cholesterol attached to the pullulan. The higher the number of cholesterol substitutions, the smaller the nanoparticle created. PA and folated PA (FPA) have been created and form self-assembled nanoparticles, which have been used to deliver epirubicin. Pullulan derivatives have been combined with gold to form self-assembled nanoparticles that were capable of loading doxorubicin. Pullulan-dexamethasone bioconjugates have been created which also exhibit self-assembling nanoparticles that have an approximate size of 400 nanometers and have shown to extend the release of the dexamethasone.
Anticancer
Pullulan is used as a bioconjugate platform in order to enhance the delivery of chemotherapeutics. Pullulan derivatives can be created in order to specifically target cancer cells. In terms of cancer therapeutics, pullulan can be used to encapsulate hydrophobic cancer therapeutics through self assembled micelles, can be linked to drugs in the form of a bioconjugate, and can be utilized for its pH responsive nature. Cancer drugs that have been used with pullulan include doxorubicin, paclitaxel, epirubicin, mitoxantrone, and 10-hydroxycamptothecin.
Pullulan derivatives can be folated in order to take advantage of the higher density of folate receptors on cancer cells. Doxorubicin has been loaded into pullulan micelles and folated micelles for targeted delivery to cancer cells through folate mediated endocytosis. The use of folated pullulan nanoparticles shows lower toxicity and higher levels of drug accumulation within the cancer cells. The pH sensitivity of pullulan also makes pullulan a good candidate for chemotherapeutic delivery, as the pullulan can be altered by the acidic environment of the tumor to provide targeted release.
Pullulan nanoparticles have also been used to deliver paclitaxel and proved to be stable under different environmental conditions. Curcumin pullulan derivatives have a great effect in targeting hepatocarcinoma cells, as the pullulan increases the ability of curcumin to solubilize, and therefore allows for the cells to properly uptake the curcumin. Pullulan micelles can also be used to deliver genes, such as p53, in order to suppress tumor development. The pullulan protects the RNA or DNA from degradation from enzymes within the body, which enables the ability of gene therapy for treatment of cancer. The addition of ascorbic acid to pullulan bioconjugates has demonstrated antimetastic properties, which can improve cation modified pullulan derivatives. There are many factors that make pullulan a suitable drug delivery platform for cancer therapeutics. Some of these factors include the chemical modifications, the pH responsiveness, as well as the ability for the pullulan to form self-assembled micelles that can protect the therapeutics from the immune system.
In vitro research has been conducted that synthesized pullulan acetate nanoparticles altered with folate and then loaded with epirubicin. This study showed that the use of folate modification to pullulan increased the cytotoxicity of the drug as well as released the drug at a faster rate than unfolated pullulan acetate. Another pullulan folated system was researched, where pullulan gold nanoparticles were folated and encapsulated doxorubicin. The pullulan gold nanoparticle provided pH controlled release of the doxorubicin and demonstrated lower toxicity to non cancer cells than doxorubicin without a carrier platform. CHP systems have been developed to deliver protein vaccines and have shown success in generating different degrees of immune responses mostly with CD4 T cells. Biotinylated pullulan acetate (BPA) have been created as they have vitamin H functionality, which helps increase the level of interaction with cancer cells. The drawback with vitamin H is that increasing the vitamin H increases the interaction of the nanoparticles with cancer cells, but also lowers the concentration of the drug in the nanoparticle due to the altered hydrophobicity. Modifications to pullulan can be made to enhance the controlled release of drugs, such as pullulan-g-poly(L-lactide) due to the water insoluble nature of the polymeric component. Doxorubicin has been conjugated to pullulan through hydrazone bonds, but was shown to have lower cytotoxic activity than doxorubicin without a delivery platform.
Intravitreal applications
The ocular space is a difficult area to deliver drugs into and therefore special drug delivery considerations need to be taken into account. Intravitreal injections are a common method of delivery drugs to the eye. Pullulan systems can be utilized in intravitreal injections in order to develop drugs that are long lasting and therefore require less frequent injections. One study looked at different chemical linkers to pullulan to test efficacy of said linkers in extending the release of rhodamine B (RhB). This study used ether (Pull-Et-RhB), hydrazone (Pull-Hy-RhB), and ester (Pull-Es-RhB) linkers to generate pullulan bioconjugates. Ex vivo modeling of the drug release indicated that the drug diffuses slower in the vitreous humor than in water. The ether bond was stable at differing pH, while the hydrazone and ester bond released the drug faster in more acidic pH, that reflected the pH of endosomes. The Pull-Hy-RhB demonstrated that this drug delivery system was capable of delivering the drug to the retina through testing of the blood in the vessels of the retina.
Further studies have investigated the creation and efficacy of pullulan-dexamethasone bioconjugates for intravitreal injections. The study synthesized self-assembling pullulan nanoparticles with dexamethasone attached through hydrazone bonds. This study reiterated that the drug release was fast in acidic pH that mimicked the pH of lysosomes. The variation in drug release was that at the pH of the vitreous humor the drug took two weeks to release half of the drug, while took only two days, when in a lysosomal pH. Pharmacokinetic analysis was performed on this bioconjugate system and revealed that dexamethasone was released in the vitreous humor and that it remained for sixteen days and that a substantial amount of the bioconjugate left the vitreous humor intact. Overall the studies regarding pullulan bioconjugates for the application in intravitreal injections demonstrate that pullulan can provide sustained release as well as allow the drug to reach the retina.
Other applications
Pullulan has many other applications. Pullulan can be used as a scaffold material for stem cells, such as mesenchymal stem cells. Pullulan can be conjugated with photosensitive molecules in order to be used with photodynamic therapy. Pullulan can be modified to be a contrast agent for MRI in multiple ways such as oxidation, iron-oxide conjugates, and cation conjugates. Pullulan has been thiolated in order to generate mucoadhesive properties. This mucoadhesive system has been further modified by polyaminating pullulan to provide sustained drug release. A study developed a transdermal pullulan system that is capable of delivering rivastigmine tartarate in response to external electrical stimuli. Pullulan systems can be loaded with a plethora of different drugs including anti-inflammatory, antilipidemic, and antiglycemic drugs. Pullulan systems can be used to treat heart conditions through the delivery of beta blockers and inhibitors of angiotensin-converting enzyme. Pullulan can also be utilized in regards to bone disease as they can be used to deliver bisphosphonates and can help to image bone regeneration through MRI.
References
Pharmacology
Biochemistry methods | Pullulan bioconjugate | [
"Chemistry",
"Biology"
] | 3,406 | [
"Biochemistry methods",
"Pharmacology",
"Biochemistry",
"Medicinal chemistry"
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70,689,462 | https://en.wikipedia.org/wiki/Baker%20Hotel%20%28Dallas%29 | The Baker Hotel was a former grand hotel located in the heart of downtown, Dallas, Texas, across the landmark Adolphus Hotel and the Magnolia Hotel. Its interiors were remodeled in 1972 after a fire, and was imploded in 1980 to make way for the Whitacre Tower, which occupies its site today.
History
Opening and events
T. B. Baker, head of the Baker Hotel Company, built the hotel in 1925. Opening night, October 25, 1925, was marked by a Gala dinner dance. According to a Dallas Morning News report, the keys to the building were officially thrown away at 6:00 Saturday morning, "thus will be symbolized the fact that the portals of the building from hence forward are never to be closed day or right." The opening was also the 30th anniversary of the opening of the old Oriental which has been torn down for the Baker to be built on the same site.
The Baker was the home of WFAA radio, the Peacock Terrace, Crystal Ballroom, and the place to play on Texas-OU weekends. Its ballrooms were used for debutantes, movie stars, and society members. The Peacock Terrace Ballroom opened in 1925, and the big name swing bands of the 20s and 30s played for Dallasites. The Idlewild Ball for Debutantes was held annually in the Crystal Ballroom. The Dallas Petroleum Club met at the Baker. The Mural Room was the main luncheon site for many.
The brownstone building catered to its patrons with style and luxury for 54 years. During that time the building sustained several mishaps.
Incidents and further sale
On June 21, 1946, an explosion ripped through the basement, injuring 3, and 9 died, though later reports say that 11 died.
The Baker's owned the hotel until 1949 when it was sold to Dallas Rupe & Sons, investment bankers. The new management retained the Baker style. In 1970 the building was sold again to Cemgil Reality.
A fire in 1971 destroyed the upper floors, and after the fire, the building was once again remodeled in 1972. Each time these incidents occurred the building was remodeled and always managed to remain elegant. Only age and new ownership finally ended the style of the Baker Hotel.
Seven years later the hotels area was included in a block purchase by Southwestern Bell Telephone.
Demolition
The new owners decided the 600-700 room hotel could not be economically converted for their needs. A sale of interior goods from chandeliers to doorknobs took place in September 1979. The Baker Hotel, along with two adjacent office buildings and a smokestack were imploded on June 29, 1980, and in seconds the once grand hotel was in complete ruin. The site was cleared and in its place a modern skyscraper known as One Bell Plaza was planned to be built.
Construction on the building began in 1982 and was completed in 1984, with 37 stories. The building is now known as One AT&T Plaza or Whitearce Tower, serving as the main headquarters of AT&T.
Gallery
References
1925 establishments in Texas
1980 disestablishments in Texas
Demolished buildings and structures in Texas
Demolished hotels in the United States
Buildings and structures in Dallas
Hotel buildings completed in 1925
Hotels established in 1925
Skyscraper hotels in Dallas
Buildings and structures demolished in 1980
Buildings and structures demolished by controlled implosion | Baker Hotel (Dallas) | [
"Engineering"
] | 669 | [
"Buildings and structures demolished by controlled implosion",
"Architecture"
] |
70,689,726 | https://en.wikipedia.org/wiki/Hygrocybe%20spadicea | Hygrocybe spadicea is a species of agaric (gilled mushroom) in the family Hygrophoraceae. It has been given the recommended English name of Date Waxcap. The species has a European distribution, occurring mainly in agriculturally unimproved grassland. Threats to its habitat have resulted in the species being assessed as globally "vulnerable" on the IUCN Red List of Threatened Species.
Taxonomy
The species was first described from Carniola (present-day Slovenia) in 1772 by naturalist Giovanni Antonio Scopoli as Agaricus spadiceus. Finnish mycologist Petter Adolf Karsten transferred it to the genus Hygrocybe in 1879.
Recent molecular research, based on cladistic analysis of DNA sequences, has confirmed that Hygrocybe spadicea is a distinct species and belongs in Hygrocybe sensu stricto.
Description
Basidiocarps are agaricoid, up to 90 mm (5 in) tall, the cap conical at first, retaining an acute or distinct umbo when expanded, up to 80 mm (3 in) across, often splitting at the margins. The cap surface is smooth, dry, and radially fibrillose, brown and typically darker at the apex. The lamellae (gills) are waxy, yellow to yellow-orange. The stipe (stem) is smooth, somewhat fibrillose, yellow at first with brownish streaks when older, lacking a ring. The spore print is white, the spores (under a microscope) smooth, inamyloid, ellipsoid, measuring about 9 to 12 by 5 to 7 μm.
Distribution and habitat
The Date Waxcap is widespread but generally rare throughout Europe. It has also been reported from Central Asia (Kazakhstan), but its identification has not been confirmed. Like other waxcaps, it occurs in old, agriculturally unimproved, short-sward grassland (pastures and lawns).
Recent research suggests waxcaps are neither mycorrhizal nor saprotrophic but may be associated with mosses.
Conservation
Hygrocybe spadicea is typical of waxcap grasslands, a declining habitat due to changing agricultural practices. As a result, the species is of global conservation concern and is listed as "vulnerable" on the IUCN Red List of Threatened Species. Hygrocybe spadicea also appears on the official or provisional national red lists of threatened fungi in several European countries, including Croatia, Czech Republic, Denmark, Estonia (where it is listed as "extinct"), Finland, Germany, Great Britain, Norway, and Sweden.
See also
List of Hygrocybe species
List of fungi by conservation status
References
spadicea
Fungi of Europe
Fungi described in 1772
Taxa named by Giovanni Antonio Scopoli
Fungus species | Hygrocybe spadicea | [
"Biology"
] | 589 | [
"Fungi",
"Fungus species"
] |
70,689,953 | https://en.wikipedia.org/wiki/Chitosan%20nanoparticles | Chitosan-poly (acrylic acid) is a composite that has been increasingly used to create chitosan-poly(acrylic acid) nanoparticles. More recently, various composite forms have come out with poly(acrylic acid) being synthesized with chitosan which is often used in a variety of drug delivery processes. Chitosan which already features strong biodegradability and biocompatibility nature can be merged with polyacrylic acid to create hybrid nanoparticles that allow for greater adhesion qualities as well as promote the biocompatibility and homeostasis nature of chitosan poly(acrylic acid) complex. The synthesis of this material is essential in various applications and can allow for the creation of nanoparticles to facilitate a variety of dispersal and release behaviors and its ability to encapsulate a multitude of various drugs and particles.
Background
Research on nanoparticles and their chitosan nanoparticles grew in popularity in the early 1990s. mainly due to its biodegradability and biocompatibility nature. Chitosan, due to its molecular structure, can be dissolved well within a variety of solvents and a variety of biologics, such as acids like formic and lactic acid. Additionally, a benefit of chitosan is its ability to be greatly modified such as with other natural materials, synthetic materials, ligands, and even functionalized with various techniques. Such an experience can be seen with the synthesis with poly-(acrylic acid) devices. The addition of poly-(acrylic acid) can allow for an interaction to induce amphiphilicity and be spontaneously assembled. This can be important due to the beneficial impact on its stimuli responsiveness and for large-scale use.
Structure, properties, and synthesis
Chitosan
Chitosan is a polysaccharide that is derived from chitin that is composed of an alkaline deacetylated monomer of glucosamine and an acetylated monomor glucosamine and binding through β-1,4 glycosidic and hydrogen bonds. The benefit of chitosan comes from their reactive groups such as -OH and -NH2. Various mechanisms for chitosan exist, and various isolation techniques can be issued for the fabrication of chitosan nanoparticles.
Chitosan nanoparticle synthesis
There are various mechanisms for chitosan nanoparticle synthesis. These mechanisms include ionic gelation/polyelectrolyte complexation, emulsion droplet coalescence, emulsion solvent diffusion, reverse miscellisation, desolvation, emulsification cross-linking, nanoprecipitation, and spray-drying.
Ionic gelation/polyelectrolyte complexation
Ionic gelation/polyelectrolyte complexation involves converting cationic chitosan solution with anionic tripolyphosphate and collecting precipitate in the form of nanoparticles.
Emulsion droplet coalescence
Emulsion droplet coalescence involves the formulation of chitosan nanoparticles by creating two stable emulsions with liquid paraffin by adding one with a stabilizer and another with sodium hydroxide again containing a stabilizer. This mixture of the two emulsions can be used to form nanoparticles.
Emulsion solvent diffusion
Emulsion solvent diffusion takes chitosan with stabilizer mixed in with an organic solvent such as methylene chloride/acetone that contains a drug that is hydrophilic and is diffused with acetone and chitosan nanoparticles are derived via centrifugation.
Reverse miscellisation
Reverse miscellisation involves taking an organic solvent lipophilic surfactant and adding chitosan with a drug and cross-linker like glutaraldehyde. The nanoparticles are then extracted.
Desolvation
Desolvation includes preparing chitosan solution and adding a precipitate with a stabilizing solution and precipitate such as acetone. Due to the insolubility of chitosan, the precipitate begins to form through the elimination of the liquid surrounding chitosan. A crosslinker such as glutaraldehyde can be added to formulate the nanoparticles
Emulsification cross-linking
Chitosan-based solution is developed in the oil face and translated into stabilized liquid. A crosslinker such as glutaraldehyde can then be used to derive chitosan nanoparticles.
Nanoprecipitation
Nanoprecipitation refers to using chitosan and dissolving it within a solvent and then having a pump to differentiate the dispersing phase and with tween 80, derive nanoparticles from the dispersing phase.
Spray drying
Spray drying involves taking chitosan and adding it to the solvent acetic acid solution. The solution will then be atomized. These droplets will be mixed with drying gas and after further evaporation, nanoparticles can be derived
Poly(acrylic acid)
Poly(acrylic acid) refers to acrylic acid that is polymerized. Poly(acrylic acid) is also known to have a neutral pH, have beneficial crosslinking properties, due to the charge properties of the side changes and poly(acrylic acid) being anionic 1,11–13,21,22. Poly (acrylic acid) is known to have good biocompatibility with chitosan, particularly with the amine groups (-NH2)
Chitosan-poly(acrylic acid) nanoparticles
An alternative method for the fabrication of chitosan nanoparticles includes the inclusion of polymerized groups of chitosan (Figure 2). This methodology can allow for the improvement of the chitosan cross-linking mechanism and improve overall drug release profiles for drugs such as amoxicillin and meloxicam. Additionally, when poly (acrylic acid) is localized within the inner shell, overall drug encapsulation can be improved.
Ionic gelation with radical polymerization
Ionic gelation with radical polymerization takes in a chitosan solution after through the addition of an acid monomer, the chitosan changes from the anion of an acrylic monomer. The nanoparticles are then derived after being self-settled overnight, and the unreacted monomer is removed. This is the main method for the formulation of poly (acrylic acid) based chitosan nanoparticles.
Applications
Biomedical applications
Biomedical applications of chitosan-based nanoparticles range from cancer treatment to regenerative medicine and tissue engineering to inflammatory diseases to diabetic treatment to the treatment of cerebral diseases, cardiovascular diseases, infectious diseases, and even for vaccine delivery. Lung cancer, breast cancer, and colorectal cancer include the top 3 cancers in terms of frequency and are responsible for 1 out of 3 cancer cases and death burden worldwide. Chitosan-based nanoparticles provide benefits to make targeted drug delivery systems for biomedical use and overall improve the potential of oral administration of drugs (Figure 3).
Figure 3 Advantages of chitosan nanoparticles. Adopted from Sharifi-Rad et al, 2021.
Drug delivery system
One of the main uses of chitosan-based nanoparticles involves drug delivery devices. The following are drugs delivered with chitosan-based nanoparticle: methotrexate, fucose-conjugated chitosan, 5-fluorouracil, doxorubicin, docetaxel, paclitaxel, propranolol-HCL, CyA, insulin, indomethacin, cefazolin, isoniazid, tetracycline, didanosine, isoniazid, rifampicin, folate, zaltoprofen, curcumin, cisplatin, camptothecin, bupivacaine, paclitaxel, prothionamide, hydrocortisone, albumin, ocimum gratissimum essential oil, triphosphate, RGD peptides and morphine. The targeting system again ranges from various drug systems, with a primary focus on targeting cancer within specific organs such as lung or colorectal. The potential of poly(acrylic acid) and the addition has shown success in improvements of overall gene expression and protein delivery through the ability to modify pH sensitivity, modify chemosensitivity, and modify targeting.
Drug encapsulating system
Another main use of chitosan-based nanoparticles involves the ability to withhold various drugs, organic compounds, and even inorganic analytes 5,8,9,11,12,23–25,28,32. These analytes include Fe3O4 (Figure 4). A Fe3O4 based chitosan poly(acrylic acid) nanoparticle or nanosphere can have applications such as toxic metal uptake for direct use in drug delivery systems, treatment of tumors, magnetic separation of biomolecules, and even MRI contrast enhancement.
Figure 4 Magnetic nanospheres with chitosan-poly(acrylic acid). Adopted from Feng et al, 2009.
Edible coating
Chitosan alone or together with putrescine has been used successfully to slow the decay of fruits for up to 12 days when held at low temperatures.
Limitations and future work
Overall continued improvement of stability, biocompatibility, degradability, and nontoxicity is needed to improve the viability. Current limitations exist in routes of delivery, such as limited work in orally administered nanoparticles and drug delivery devices. Absorption should further be improved in chitosan poly(acrylic acid) nanoparticles for improved solubility for targeted drug delivery. Additionally, further work in cell viability and cell proliferation is needed within these nanoparticles for use in tissue regeneration. Additionally, current limitations exist in fabrication techniques and large chain implementation due to possible difficulties in the synthesis of chitosan-based nanoparticles.
References
Nanoparticles by composition
Biomaterials
Polysaccharides | Chitosan nanoparticles | [
"Physics",
"Chemistry",
"Biology"
] | 2,132 | [
"Biomaterials",
"Carbohydrates",
"Materials",
"Medical technology",
"Matter",
"Polysaccharides"
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70,690,037 | https://en.wikipedia.org/wiki/Russian%20filtration%20camps%20for%20Ukrainians | Filtration camps, also referred to as concentration camps, are camps used by Russian forces during the Russian invasion of Ukraine to register, interrogate, and detain Ukrainian citizens in regions under Russian occupation before transferring them into Russia, sometimes as part of forced population transfers. Filtration camp detainees undergo a system of security checks and personal data collection. Detainees are subject to widespread torture, killings, rape, starvation and other grave human rights violations.
The number of Ukrainian citizens relocated to Russia cannot be independently verified. According to the Ukrainian government, some 1.6 million Ukrainians have been forcibly relocated to Russia, with about 250,000 of these being children. The Russian government denies it is forcibly removing Ukrainians to Russia and calls the deportations "evacuation".
According to a leaked Russian occupation plan, "filtration" was to represent the foundation of their counter-insurgency and pacification strategy, with Russian occupation authorities planning to pass large portions of the Ukrainian population through the "filtration" process after occupying the entire country.
Overview
Occupying powers in international conflicts have the right to register persons within their area of control or even detain civilians under certain circumstances, however, Russia's filtration system violates multiple elements of international humanitarian law and may involve multiple grave human rights abuses.
Ukrainians in Russian-occupied zones are often left unable to flee into Ukrainian-held territory, having to either stay in areas experiencing unliveable conditions or flee to other areas under Russian control or into Russia itself. To enter Russia, many Ukrainians are forced to undergo "filtration", a process during which they are interrogated, and their biometric data is taken. While awaiting "filtration", Ukrainians are settled in so-called "filtration camps", set up ad hoc in various public buildings where the "filtration" takes place. After passing "filtration", Ukrainians are reportedly often forcibly transferred to the Russian Far East.
According to Meduza, filtration most likely occurs either at "filtration posts" which are essentially border crossing points where people have been obliged to voluntarily wait their turn due to the large influx of people trying to cross, or at actual filtration camps where people awaiting "filtration" are temporarily detained.
According to a leaked Russian occupation plan, "filtration" was intended to serve as pacification and counter-insurgency strategy following Russian occupation of the entirety of Ukrainian territory. According to the occupation plans, large portions of the Ukrainian populations were to be rounded up during door-to-door sweeps and passed through "filtration" in order to compile comprehensive counter-intelligence files: "Filtration would be used to intimidate people, to determine whether they needed to be displaced into Russia, and to lay the groundwork for records to monitor and disrupt resistance networks."
Location of the filtration camps
As of June 2022, most filtration camps were attested to be located in towns and villages across the puppet quasi-state Donetsk People's Republic. Filtration camps have been set up in what had previously been public buildings like schools, cultural centres, sports halls, community centres, police stations, and makeshift camp areas.
In a July 2022 statement to the OSCE, a U.S. diplomat stated that the U.S. had identified at least 18 filtration camp sites set up by Russia both in Ukrainian and Russian territory, with preparations of filtration camps having been undertaken even before the beginning of the Russian invasion of Ukraine. The filtration camps had been set up in Ukrainian territory that had recently come under Russian occupation by Russian officials working alongside proxy groups, the U.S. diplomat said. The U.S. diplomat said the filtration camps were set up in what had been schools, sport centres, and cultural institutions. An article published by the Polish Spokesman for the Minister Coordinator of Special Services found and published the location of six such camps "where there are Russian torture chambers used against Ukrainians."
Intake and detention
Fleeing Ukrainians have been transferred into filtration camps unknowingly, being falsely told that they are being taken to Ukrainian-held territory. Some are forced to pass "filtration" while fleeing combat or forcibly herded into the process by occupation forces or authorities, while still others agree to undergo the process in order to be able enter Russia or continue travel within occupied areas.
After arriving in filtration camps, detainees are told they are not allowed to leave the town in which the filtration camp is located as they await "filtration". Detention in filtration camps have been reported to last anywhere from hours to many weeks.
Living conditions
Living conditions in the camps are often squalid. The camps are poorly organised. Those detained in the camps described sleeping on the floors or on cardboard, living in poor sanitary conditions, and meal rations that were scant or altogether absent.
"Filtration" and interrogation
During filtration, detainees are photographed, fingerprinted, interrogated, and the contents of their phones are examined. They undergo detailed interrogations about personal background, family ties, and political views and allegiances. Detainees are questioned about whether they know anyone serving in the Ukrainian army. Detainees are asked about their political views and any ties to the Azov Regiment. Men and in some instances women are strip-searched to be examined for Ukrainian nationalist tattoos. During "filtration", men have been subjected to inspections looking for possible signs of bruising from body armour or rifle use. Officials involved in the "filtration" process have said that the collected information is used to populate a database.
"Filtration" usually ends in one of two ways: either the detainee is given a document certifying that they have passed filtration, or they are detained for further interrogation. Even after passing "filtration", some men are interrogated again during their passage from the filtration camp across areas under Russian control. Children are sometimes separated from their parents and separately transferred to Russia during filtration as part of the child abductions in the 2022 Russian invasion of Ukraine.
According to the U.S. State Department, Ukrainians with affiliations with the Ukrainian armed forces, government, media, or civil society are "filtered" from the rest of the detainees, and subject to transfer to detention facilities where they reportedly face torture, and summary execution.
Violence, torture, and killings
Detainees perceived as having ties to the Ukrainian armed forces or Ukrainian state, pro-Ukrainian and/or anti-Russian views are subject to maltreatment, arbitrary detenion, torture, and forced disappearance. Beatings, torture with electricity, and killings have been reported by people interrogated in the filtration camps. Women and girls are at risk of sexual abuse. One witness said filtration camp staff forced detainees to give false testimony (blame Ukraine for destroying their homes) on camera.
Release and forced deportations
After passing "filtration", some people are released within the DNR, while others are deported onward into Russia. People that have passed through the filtration camps have said that they had been ultimately sent to various cities across Russia after their release from the filtration camps, with many having been sent to the Russian Far East. After arriving in Russia, they are usually first temporarily placed in refugee centres before being instructed or coerced by Russian officials to travel to other destinations within Russia, while some are able to go to stay with relatives or friends in Russia, arrange their own accommodation in Russia, or leave Russia. Russian officials have pressured Ukrainians placed in temporary refugee centres to apply for asylum or Russian citizenship, or face indefinite detention in the centres. Some are interrogated again by Russian officials after arriving in Russia. Ukrainians are not officially prohibited from leaving Russia, but in practice face obstacles (sometimes significant ones) in doing so. An ad hoc network of activists has emerged to help Ukrainians leave Russia. According to the U.S. State Department, Ukrainian citizens are coerced to sign agreements to stay in Russia prior to their release from filtration camps, thereby hindering their return to Ukraine.
Ukrainian intelligence has said that Ukrainian citizens released from filtration camps are offered employment in economically depressed regions of Russia by Russian employment centres.
Mikhail Mizintsev, chief of Russia's National Defense Management Center, said in May 2022 that 1,185,791 people have been transferred into Russia. According to the U.S. State Department, "between 900,000 and 1.6 million Ukrainian citizens, including 260,000 children" have passed through the "filtration" process and deported, "often to isolated regions in the Far East" in a "pre-meditated [...] apparent effort to change the demographic makeup of parts of Ukraine".
Remaining in Russia
Russia has enacted measures to facilitate the process of granting temporary asylum and Russian citizenship to Ukrainians. In April 2022, Russia adopted federal legislation which includes provisions streamlining applications for Russian citizenship for Russian-speaking Ukrainians from Donbas. On March 5, 2022, Putin signed a decree to help civilians fleeing hostilities that established a simplified administrative procedures for Ukrainians entering Russia and seeking asylum or citizenship. Ukrainians arriving in Russia from the DNR and LNR are entitled to a one-time cash payment. Asylum seekers and refugees in Russia are entitled a number of rights, including food and temporary accommodation, and resources and support in finding work and housing; in practice, people face significant obstacles in claiming these rights. Ukrainians must hand over their passport to obtain a temporary asylum card without being informed that they are entitled to retrieve their passport and exit Russia, leading some to believe they are not allowed to exit Russia.
Escape from "filtration" and forced deportation
Ukrainians that have fled into Georgia have avoided forced deportations into Russian cities that are reportedly common after passing "filtration". Some Ukrainians that were detained in filtration camps have said that informing filtration camp officials that they have concrete plans to go to a specific Russian city enabled them to be released and told to find their own way there, thus enabling them to escape into Georgia and avoid forced transfers.
Some people reported that they needed to slip out of filtration camps in Novoazovsk or post-filtering from Taganrog or Rostov-on-Don to escape through neighboring countries like Georgia, rather than be forcibly sent to distant parts of Russia.
History
On 15 March 2022, The Guardian reported that witnesses have said that Russian troops have ordered women and children out of a bomb shelter in Mariupol. One witness said they were forcibly bussed with two or three hundred others to Novoazovsk, where they had to wait for hours inside the buses until they were ordered to go through a group of tents to what was called a filtration camp. Satellite imagery showed a group of tents in Bezimenne, near Novoazovsk. Representatives of Donetsk People's Republic and Luhansk People's Republic said they had set up a "tent city of 30 tents" with a capacity for 450 people.
Russian government newspaper Rossiyskaya Gazeta reported that 5,000 Ukrainians had been processed in the Bezimenne camp and that they had run checks to prevent "Ukrainian nationalists from infiltrating Russia disguised as refugees so they could avoid punishment." One witness said she was extensively questioned by men who said they were from the FSB. She was questioned about her background and described the questioning as "very degrading". The group was then taken to Rostov.
In May 2022, videos with Ukrainian civilians apologizing to Russian soldiers, with some of them saying that they had undergone a "denazification course", have appeared on social media.
In November 2022, the Head of the UN Human Rights Monitoring Mission in Ukraine, Matilda Bogner, reported on the "admission procedures" in the penal colony near Olenivka, which often involved beatings, threats, dog attacks, mock executions, forced nudity, electric and positional torture. The UN agency also reported receiving information about nine deaths in Olenivka in April 2022.
In December 2022, OHCHR reported that Russian security services may have forcibly disappeared a woman who had failed the "filtration process" in the Rostov region on 10 October.
Reactions
Russia
The Russian Embassy in the United States has said the filtration camps are "checkpoints for civilians leaving the zone of active hostilities".
Ukraine
Ukrainian officials have compared the filtration camps to filtration camps in Chechnya.
United States
United States ambassador to the UN Linda Thomas-Greenfield said "I do not need to spell out what these so-called 'filtration camps' are reminiscent of. It's chilling and we cannot look away". She cited reports that FSB agents confiscated passports, IDs and mobile phones, as well as reports of Ukrainian families being separated. The US envoy to the OSCE, Michail Carpenter, told the organization's permanent council that according to credible reporting, Ukrainian civilians in the filtration camps were interrogated and those suspected of ties to independent media or the military were beaten or tortured before being transferred to the Donetsk region, "where they are reportedly disappeared or murdered."
Civil society
Tanya Lokshina, director of Human Rights Watch for Europe and Asia, said: "Under international human rights law, forced displacement or transfer doesn't necessarily mean people were forced into a vehicle at gunpoint, but rather that they found themselves in a situation that left them no choice." She pointed out that the Geneva Convention prohibits "individual or mass forcible transfers, as well as deportations of protected persons from occupied territory, are prohibited, regardless of their motive".
In an interview to Current Time TV, human rights activist Pavel Lisyansky said that the "courses" are often accompanied by physical violence, moral pressure and humiliation, and compared them to the "re-education" of Uyghurs by the Chinese government, which likely inspired these filtration camps and methods. Lisyansky also said that he knows three or four cases of Ukrainian civilians getting killed and their documents destroyed after they had a conflict with their "curator".
See also
Claims of genocide of Ukrainians in the 2022 Russian invasion of Ukraine
Filtration camp system in Chechnya
Gulag – the prison system of the USSR
List of concentration and internment camps#Russia and the Soviet Union
Political prisoners in Russia
Russian war crimes
Xinjiang internment camps
References
Further reading
Danny Gold, "'We Will Never Be the Same': Bullets and Blindfolds in a Ukrainian City Under Siege", Vanity Fair, 19 May 2022.
"Filtration" and the Crime of Forcibly Transferring Ukrainian Civilians to Russia - Human Rights Watch, 1 September 2022
Russia’s Unlawful Transfer And Abuse of Civilians In Ukraine During ‘Filtration’ - Amnesty International, 1 November 2022
2022 in Ukraine
2022 in Russia
Internment camps in Ukraine
Military prisoner abuse scandals
Deportation
Total institutions | Russian filtration camps for Ukrainians | [
"Biology"
] | 3,097 | [
"Behavioural sciences",
"Behavior",
"Total institutions"
] |
70,690,897 | https://en.wikipedia.org/wiki/Polystyrene%20%28drug%20delivery%29 | Polystyrene is a synthetic hydrocarbon polymer that is widely adaptive and can be used for a variety of purposes in drug delivery. These methods include polystyrene microspheres, nanoparticles, and solid foams. In the biomedical engineering field, these methods assist researchers in drug delivery, diagnostics, and imaging strategies.
A common group of medication that utilizes a combination of polystyrene and sulfonate functional groups are polystyrene sulfonates. This medication is primarily used to treat hyperkalemia, a condition that results from an increased blood potassium level. FDA approved equivalents of polystyrene sulfonates are KIONEX, KALEXATE, and SPS. While these are the only current FDA approved drug that utilizes polystyrene, polystyrene sees a number of applications in other pharmacological contexts with nanoparticles and microspheres.
Drug Delivery Applications
Solid foams
Polystyrene integrated solid foams are not commonly used in biomedical applications but have shown promise as a new drug delivery vehicle. The manipulation of the porous foam networks is a fundamental component in solid foam dosing – affecting variables such as dissolution, adsorption, and drug diffusion. Solid foam structures are particularly attractive due to the predictability in drug release profiles through the highly tunable porosity and high surface area of these foams.
The process of creating these structures is typically a hassle, requiring multiple step processes in order to synthesis a foam of desired properties. However, polystyrene solid foams have been created through simpler methods such as extrusion from a blowing agent or polystyrene bead expansion. While these methods are typically utilized for insulation or similar industry uses, this production method has also seen use in drug delivery applications [5]. Polystyrene solid foams can also be produced through emulsions. An emulsion can be created through the combination of two immiscible liquids. While many methods are used to create emulsion, Canal et al. used a unique method known as phase inversion temperature (PIT). PIT utilizes phase transitions to produce highly concentrated amounts of emulsion quickly. Through changes in temperature, solubility, and low interfacial tension, PIT is able to efficiently promote emulsion. The porosity of these solid foams is able to be fine-tuned, showing promise for osteogenic and therapeutic applications. For example, proposed osteogenic applications include the promotion of bone integration. The study conducted by Canal et al., utilized polystyrene solid foams as a drug delivery method to evaluate the drug release profile of ketoprofen. Researchers have stated that understanding the release profile for various drugs with polystyrene solid foams could significantly improve treatment outcomes for many disease states.
Nanoparticles
Nanoparticles have been used in drug delivery for applications such as diagnosis and treatment of diseases, with polymeric nanoparticles gaining significant traction as a carrier of drugs or biomolecules over the last few decades. These structures are extremely small, having a diameter < 100 nm. The high surface to volume ratio allows nanoparticles to display properties that are different than their bulk material in biological systems. These properties have been the sole reason of their use in physiological environments. While the structure of nanoparticles is straightforward, the efficacy of nanoparticles is affected by variables such as size and surface modifications which determines their overall biocompatibility and biological interaction.
Size and Nanoparticle Internalization
Polystyrene nanoparticles are the model nanoparticle used for drug delivery applications because they are easy to synthesize in varying sizes. Size is an important factor in cellular uptake rates, which is important for specific pathways such as the endocytic pathway. In a study conducted by Rejman et al., researchers were able to show that polystyrene nanoparticles with diameters of 50 nm and 100 nm were internalized faster than nanoparticles with diameters of 200 nm and 500 nm. Internalization is vital in understanding the impact the designed nanoparticles are having on the target cells. Nanoparticle internalization depends on a couple of key factors such as nanoparticle size, cell type, and time. Nanoparticles of larger size are typically internalized through processes such as phagocytosis or micropinocytosis. Smaller nanoparticles are typically internalized through processes such as macro-pinocytosis, phagocytosis, clathrin-mediated endocytosis, caveolae-mediated endocytosis, and clathrin-and caveolae-independent pathways. The diversity in pathways is one of the greatest challenges with utilizing these nanoparticles since a case-by-case approach is typically required to maximize the entry pathways. To measure nanoparticle internalization, techniques such as fluorescence activated cell sorting/scanning (FACS), inductively coupled plasma (ICP) mass spectroscopy, confocal laser scanning microscopy (CLSM), and imaging flow cytometry (IFC) are utilized, each offering their own advantages and disadvantages.
Biocompatibility and Biological Integration
The main advantage of polystyrene nanoparticles is their biocompatibility, which allows them to be used broadly for biomedical devices and the study of bio-nano interactions. Furthermore, their ability to not degrade in cellular environments proves to be an asset in biomedical applications. A unique property of polystyrene nanoparticles, like some other polymers, is their ability to fuse with proteins. When proteins bind to the surface of the nanoparticle, a protein corona is formed. A protein corona encapsulates the identity of the nanoparticle, and the properties of the corona can be manipulated based on the physical properties of the nanoparticle. The corona can be defined as “soft” or “hard” depending on bonding strength and surface-bound protein exchange rate. As such, a soft protein corona is defined by nanoparticles that are loosely bound and proteins that are easily exchangeable. In contrast, a hard protein corona has nanoparticles that are tightly bound and proteins that are not as easily exchangeable. These kinetics are vital in understanding how nanoparticles will respond in biological fluid. The hardness of the protein corona plays a role in the Vroman effect, a principle that describes how proteins with higher affinities replace proteins of lower affinity [8], [11]. The Vroman effect is influenced by protein concentration relative to the surface area and diffusion coefficients. Overall, this affects the protein surface binding affinity. For example, Ehrenburg et al. have shown that fibrinogen presence rapidly declines with polystyrene nanoparticles containing functional groups, such as COOH and CH3. This allows a protein such as albumin, with a lower affinity, to adsorb and become replaced by fibrinogen. Overall, polymeric nanoparticles that can fuse with proteins have a significant advantage over other polymeric nanoparticles due to this versatility in biological interaction.
Surface Modifications
Certain properties of polystyrene nanoparticles can be modified depending on the scenario. For instance, the surface of polystyrene nanoparticles can be manipulated by surface oxidation, which creates a surface that is highly receptive with cell cultures. These surface-level modifications also express a lower polydispersity index and can create stable colloids in biological liquid. Similarly, the surface of these nanoparticles can be treated with ethylene oxide or UV irradiation for sterilization purposes. Due to the emphasis on biocompatibility, Loos et al. have utilized polystyrene nanoparticles as a model to analyze how different surface properties affect biomedical variables. Overall, it was determined that a strong understanding of surface properties is vital to manipulate parameters such as pharmacokinetics, biocompatibility, and tissue and cell affinity. In a study conducted by Lundqvist et al., the protein corona was studied with three surface modified polystyrene (plain, carboxyl-modified, and amine-modified) nanoparticles of two different sizes (50 nm and 100 nm). This study ultimately showed that surface corona properties are also affected by size and surface composition.
Current Applications
Polystyrene nanoparticles have been used in various applications such as cancer treatment. The primary issue associated with treating cancer is that many chemotherapies suffer from poor penetration into tumor cells. In a study conducted by Larina et al., researchers utilized polystyrene nanoparticles in conjunction with ultrasound radiation to influence tumor regression. They proposed a method of utilizing ultrasound-induced cavitation to enhance drug delivery to cancer cells. Nanoparticles have typically been used in these applications because they are able to accumulate in these tumor sites actively or passively. For this application, since cavitation is an important factor, polystyrene nanoparticles were used since their presence allows cavitation to occur at lower pressure intensities. Within mice models, their study found that ultrasound irradiation and polystyrene nanoparticles with a combination of 5-FU injections showed strong levels of tumor inhibition and total tumor regression.
The effect of polystyrene nanoparticles on various cell lines have also been researched. Application with human gastric adenocarcinoma cell (AGS) lines has been studied due to these cells being the first line of contact with nanoparticles from ingestion. The goal of the study by Forte et al. was a further understanding of nanoparticle interaction with biological systems by studying the kinetic uptake of polystyrene nanoparticle uptake by AGS cells. Just as previous studies have shown, it was concluded that the primary factors that influence drug delivery strategies are the size and concentration of these nanoparticles.
Polystyrene nanoparticle composites have also been the focus of literature due to their adaptability. Composites are useful since the properties for the constituent materials can be combined in a way that is unlike the original components. This is extremely relevant in drug delivery applications to fine tune specific parameters case-by-case. In a study conducted by Lim et al., a composite of mono-disperse Fe3O4 and polystyrene nanoparticles were utilized for cardiac myocyte treatment via magnetic targeting. Other polystyrene composites have been created with silica nanoparticles. These materials are attractive for a number of reasons such as having low toxicity, being able to control its particle size, strong chemical and thermal stability, biocompatibility, and degradability in physiological environments. Since many of these properties are already present in polystyrene nanoparticles (i.e., biocompatibility and particle size), these structures only enhance its effect in biological environments. As a result, composites such as these have seen increased use a mode of drug delivery.
Microspheres
Microspheres (or microparticles) are a group of small spherical particles that typically have a diameter ranging from 1 μm to 1000 μm. While microspheres can be created through natural or synthetic purposes, synthetic polymer microspheres offer useful advantages over other options. The most common types of polymeric microspheres are polyethylene and polystyrene; however, polystyrene microspheres are especially useful in biomedical applications because they are able to actively facilitate cell sorting and immunoprecipitation. This results in proteins and ligands adsorbing readily, similar to polystyrene nanoparticles. Polystyrene microparticles are also hydrophobic meaning that they will not swell when exposed to a biological environment. Microspheres are applicable with a myriad of drug delivery applications (e.g., ophthalmic, gene, intra-tumoral, local, oral, nasal, gastrointestinal, peroral, vaginal, transdermal, and colonic drug delivery). Polystyrene microspheres have also seen use in magnetic and radiolabeled microspheres. Similarly, model microspheres such as carboxylated polystyrene microspheres have been used for many studies due to high ligand conjugation through carbodiimide chemistry.
Microsphere Synthesis
The way that microspheres are prepared can influence their physical properties. Preparation methods such as precipitation polymerization, seed polymerization, microemulsion, and dispersion polymerization have been used in the past to create polystyrene microspheres. Precipitation polymerization is a robust method of polymer synthesis where a monomer and initiator are dissolved in a solvent. This method is advantageous due to low viscosities, clean surfaces, low solid content, and irregular geometries, factors which are beneficial in physiological environments. Seed polymerization is a preparation method used to create core-shell emulsions. These structures have good stability and narrow particle size distribution, however, due to a long and complex preparation process there is a high likelihood of monomers becoming embedded inside the particles. Microemulsions are a method of creating emulsions through an emulsifier. By creating particles with microbubbles, this method can create particles that have similar particle size and stability. Dispersion polymerization is a method of creating particles with similar size with the advantage of being easy to perform and operate. With this method, particle size can easily be modified by manipulating the concentrations of stabilizer, co-monomer, and water. Due to these reasons, dispersion polymerization has become one of the primary methods of polystyrene microsphere synthesis. Each of these methods offer their own advantages and disadvantages and are chosen for microsphere synthesis accordingly.
Current Applications
Polystyrene microspheres have previously been used for serological tests (i.e., rheumatoid arthritis, disseminated lupus erythematous, and pregnancy tests). Saravanan et al. have shown that polystyrene microspheres can be used for controlled drug delivery applications with ibuprofen. One of the biggest limitations associated with drug delivery is that intravenously injected drug carriers (e.g., microspheres and liposomes) become trapped by mononuclear phagocyte system (MGS) cells. This limitation is important to overcome for the progression of treatment outcomes for diseases such as AIDS and tuberculosis which primarily rely on the macrophage response system. A study by Makino et al. delved into the required size and surface modifications required for alveolar macrophages to uptake polystyrene microspheres. It was shown that microspheres with a softer surface were more accessible to alveolar macrophages. Moreover, primary amine groups were also shown to be more effective over carboxyl groups. As a result, polystyrene microspheres have seen increased use a mode of drug delivery.
Polystyrene Toxicity
One of the most important factors to consider is the toxicity of the polystyrene particles. Many in vitro studies have been conducted to understand how these structures can affect reactive oxygen species generation and cell viability. Overall, these studies showed that polystyrene nanoparticles did not affect cell viability.
Similarly, it is important to consider polystyrene toxicity in human models. The use of polystyrene has been under scrutiny by various international and local agencies due to the effects of polystyrene on the environment. As a result, there has always been a cause for concern for how polystyrene can affect human health. The Environmental Protection Agency (EPA) and studies conducted by Mutti et al. claim that the chronic toxicity of styrene is 300ppm (1,000 μg/m3). Within the polymer industry, these levels typically don't go over 20ppm. Furthermore, the FDA reports that the admissible daily intake (ADI) is 90,000 μg/person/day.
References
Drug delivery devices | Polystyrene (drug delivery) | [
"Chemistry"
] | 3,364 | [
"Pharmacology",
"Drug delivery devices"
] |
70,691,093 | https://en.wikipedia.org/wiki/Magnaporthe%20rhizophila | Magnaporthe rhizophila is a fungus species in the family Magnaporthaceae. These dark mycelial fungi are common pathogens of cereal and grass roots. Rice blast is one disease known to be caused by M. rhizophila and presents with vascular discoloration in the host organism. The fungus lives best in drier humid conditions, explaining why it is most often found in the soils of Australia, South Africa, and the Southeastern United States.
Development
Similar to other ascomycota, the lifecycle of M. rhizophila is split into two parts: the sexual and asexual stages. The sexual lifestage is characterized by a globose (400-500 um wide) fruit-like body that contains the sexual spores, called a perithecia, which occurs in either singles or multiples. Perithecia are flask-like shaped and contain asci, which are septated, unitunicate stalks of 8 ascospores. The ascospores are biseriate, fusiform, and slightly curved or helical when naive. The perithecia is lined with cells called the peridium and has accessory structures called periphyses and paraphyses that surround the outside and inside of the structure, respectively. Paraphyses inside the perithecia dissolve once asci reach maturity. The asexual lifestage is characterized by asexual conidial structures (6-20x2-6 um). Conidiophores are either simple or branched.
Compared to the fruiting bodies of other Magnaporthe species, rhizophila is considered faster growing (0.8 cm/d at 28 °C) with slightly longer and wider conidial cells.
M. rhizophila is homothallic, so it is self-fertile and can mate with similar mating types within its own mycelia.
Ecology
Magnaporthe rhizophila is considered a necrotrophic parasite because it relies on the nutrients and support of other organisms to thrive. It is a heterotroph since it is unequipped to sequester energy on its own, hence its symbiotic behavior. Magnaporthacaea are family-specific soil-borne parasites of Gramineae; rhizophila specifically colonizes the roots of millet.
Spores from M. rhizophila are dispersed by natural manners such as wind, water, and animals. These spores then settle in soil where they grow and mature through asexual life cycles until it is optimal for the hyphae to resume a sexual cycle and a host organism is near. Rhizophila is only root-infecting; however many of its Magnaporthe relatives are both soil and aerial-infecting. The fungus has an appressorium structure which functions to elicit effector hormones to increase host susceptibility (2 clade-specific types of small specific proteins (SSP) ). Lignitubers have been considered a response by host cells after infection as a response to fungal invasion. However, rhizophila kills host cells in 5–6 weeks.
M. rhizophila has darkly pigmented hyphae, composing mycelia that has a gray-brown color, darker than species in the rest of its family. It is able to be cultured in vitro and survives on PDA (potato dextrose agar) plates.
Geographical distribution
Magnaporthe rhizophila does not necessarily require much water to survive, localizing in drier humid regions of Australia, South Africa, and the Southeastern United States.
Genetics
From data derived from genetic testing, it was found that M. rhizophila originated in South Africa. Fungal fossils demonstrated that the phyla diverged 31 million years ago from other Sordariomycetes, and the phylogeny diverged 21 million years ago from pezizomycotina.
Magnaporthe species are grouped into three divergent clades; rhizophila is in clade classification D along with M. poae and G. incrustans. Rhizophila belongs to the Magnaporthe family based on its ascospore morphology; however, it has been considered for the Gaeumannomyces because they also produce phialophora-like anamorphs instead of sympodial pyricularia. M. rhizophila is the only known Magnaporthe species with a phialophora anamorph. Given these similarities between families, M. rhizophila is highly hybridized with other species among these groups.
The M. rhizophila genome is composed of 5.8% transposable elements, lower than other species in its family.
References
Magnaporthales
Fungus species | Magnaporthe rhizophila | [
"Biology"
] | 993 | [
"Fungi",
"Fungus species"
] |
70,691,095 | https://en.wikipedia.org/wiki/HD%2011025 | HD 11025 (HR 525) is a suspected astrometric binary in the southern circumpolar constellation Octans. It has an apparent magnitude of 5.67, making it visible to the naked eye if viewed under ideal conditions. Located 378 light years away, it is receding with a heliocentric radial velocity of .
The visible component is a yellow giant of spectral class G8 III. At present it has 2.61 times the mass of the Sun but at an age of 500 million years, has expanded to 9.52 times the radius of the Sun. It shines at from its enlarged photosphere at an effective temperature of , giving it a yellow glow. HD 11025 has a solar metallicity and spins with a moderate projected rotational velocity of .
References
Octans
G-type giants
011025
007568
0525
PD-85 17
Octantis, 4 | HD 11025 | [
"Astronomy"
] | 183 | [
"Octans",
"Constellations"
] |
70,691,232 | https://en.wikipedia.org/wiki/Two-dimensional%20space | A two-dimensional space is a mathematical space with two dimensions, meaning points have two degrees of freedom: their locations can be locally described with two coordinates or they can move in two independent directions. Common two-dimensional spaces are often called planes, or, more generally, surfaces. These include analogs to physical spaces, like flat planes, and curved surfaces like spheres, cylinders, and cones, which can be infinite or finite. Some two-dimensional mathematical spaces are not used to represent physical positions, like an affine plane or complex plane.
Flat
The most basic example is the flat Euclidean plane, an idealization of a flat surface in physical space such as a sheet of paper or a chalkboard. On the Euclidean plane, any two points can be joined by a unique straight line along which the distance can be measured. The space is flat because any two lines transversed by a third line perpendicular to both of them are parallel, meaning they never intersect and stay at uniform distance from each-other.
Curved
Two-dimensional spaces can also be curved, for example the sphere and hyperbolic plane, sufficiently small portions of which appear like the flat plane, but on which straight lines which are locally parallel do not stay equidistant from each-other but eventually converge or diverge, respectively. Two-dimensional spaces with a locally Euclidean concept of distance but which can have non-uniform curvature are called Riemannian surfaces. (Not to be confused with Riemann surfaces.) Some surfaces are embedded in three-dimensional Euclidean space or some other ambient space, and inherit their structure from it; for example, ruled surfaces such as the cylinder and cone contain a straight line through each point, and minimal surfaces locally minimize their area, as is done physically by soap films.
Relativistic
Lorentzian surfaces look locally like a two-dimensional slice of relativistic spacetime with one spatial and one time dimension; constant-curvature examples are the flat Lorentzian plane (a two-dimensional subspace of Minkowski space) and the curved de Sitter and anti-de Sitter planes.
Non-Euclidean
Other types of mathematical planes and surfaces modify or do away with the structures defining the Euclidean plane. For example, the affine plane has a notion of parallel lines but no notion of distance; however, signed areas can be meaningfully compared, as they can in a more general symplectic surface. The projective plane does away with both distance and parallelism. A two-dimensional metric space has some concept of distance but it need not match the Euclidean version. A topological surface can be stretched, twisted, or bent without changing its essential properties. An algebraic surface is a two-dimensional set of solutions of a system of polynomial equations.
Information-holding
Some mathematical spaces have additional arithmetical structure associated with their points. A vector plane is an affine plane whose points, called vectors, include a special designated origin or zero vector. Vectors can be added together or scaled by a number, and optionally have a Euclidean, Lorentzian, or Galilean concept of distance. The complex plane, hyperbolic number plane, and dual number plane each have points which are considered numbers themselves, and can be added and multiplied. A Riemann surface or Lorentz surface appear locally like the complex plane or hyperbolic number plane, respectively.
Definition and meaning
Mathematical spaces are often defined or represented using numbers rather than geometric axioms. One of the most fundamental two-dimensional spaces is the real coordinate space, denoted consisting of pairs of real-number coordinates. Sometimes the space represents arbitrary quantities rather than geometric positions, as in the parameter space of a mathematical model or the configuration space of a physical system.
Non-real numbers
More generally, other types of numbers can be used as coordinates. The complex plane is two-dimensional when considered to be formed from real-number coordinates, but one-dimensional in terms of complex-number coordinates. A two-dimensional complex space – such as the two-dimensional complex coordinate space, the complex projective plane, or a complex surface – has two complex dimensions, which can alternately be represented using four real dimensions. A two-dimensional lattice is an infinite grid of points which can be represented using integer coordinates. Some two-dimensional spaces, such as finite planes, have only a finite set of elements.
Further reading
Dimension
Multi-dimensional geometry
2 (number) | Two-dimensional space | [
"Physics"
] | 886 | [
"Geometric measurement",
"Dimension",
"Physical quantities",
"Theory of relativity"
] |
70,691,371 | https://en.wikipedia.org/wiki/Meta-waveguide | In photonics, a meta-waveguide is a physical structures that guides electromagnetic waves with engineered functional subwavelength structures. Meta-waveguides are the result of combining the fields of metamaterials and metasurfaces into integrated optics. The design of the subwavelength architecture allows exotic waveguiding phenomena to be explored.
Meta-waveguides can be classified by waveguide platforms or by design methods. If classified by underlying waveguide platform, engineered subwavelength structures can be classified in combination with dielectric waveguides, optical fibers, or plasmonic waveguides. If classified by design methods, meta-waveguides can be classified as either using design primarily by physical intuition, or by computer algorithm based inverse design methods.
Meta-waveguides can provide new degrees of design freedom to the available structural library for optical waveguides in integrated photonics. Advantages can include enhancing the performance of conventional waveguide based integrated optical devices and creating novel device functionalities. Applications of meta-waveguides include beam/polarization splitting, integrated waveguide mode converters, versatile waveguide couplers, lab-on-fiber sensing, nano-optic endoscope imaging, on-chip wavefront shaping, structured-light generations, and optical neural networks. The meta-structures can also be further integrated with van der Waals materials to add more functionalities and reconfigurability.
References
Photonics
Nanotechnology
Applied and interdisciplinary physics
Electromagnetic radiation | Meta-waveguide | [
"Physics",
"Materials_science",
"Engineering"
] | 310 | [
"Physical phenomena",
"Applied and interdisciplinary physics",
"Electromagnetic radiation",
"Materials science",
"Radiation",
"Nanotechnology"
] |
70,691,380 | https://en.wikipedia.org/wiki/Museo%20Cabeza%20de%20Ju%C3%A1rez | The Museo Cabeza de Juárez (English: Head of Juárez Museum) is a museum and monument in Iztapalapa, Mexico City. The top of the structure features a colossal head of Benito Juárez, the 26th president of Mexico. Luis Echeverría, the 57th president of the country, ordered its erection in 1972 – a century after Juárez's death – and it was inaugurated on 21 March 1976, the 170th anniversary of Juárez's birth. The museum's collection features the chronology of Juárez's life, and its esplanade is open for cultural events. Artists Luis Arenal Bastar and David Alfaro Siqueiros were involved in its construction and design.
History and construction
Luis Echeverría ordered the erection of a monument to Benito Juárez in 1972. The selected space was a roundabout along Guelatao Avenue in Iztapalapa, Mexico City. Architects Lorenzo Carrasco Ortiz and Miguel Ramírez Bautista designed the civil work. Meanwhile, David Alfaro Siqueiros was hired to paint murals on the walls, but his health began to deteriorate and he died in 1974. Luis Arenal Bastar, Siqueiros's brother-in-law, replaced him and additionally sculpted the colossal head with help of Carrasco Ortiz.
After its inauguration, the sculpture ceased to receive federal support and fell into decline. It was not until 2000 that it received its first major restoration by the government of the city, where the plinth was transformed into a museum. Following the earthquake of 19 September 2017, the museum received minor damage and the subsequent maintenance cost two million pesos. During the process, signs of corrosion and various bullet impacts were found.
The plinth-transformed-into-museum is high, wide and deep. The external walls are painted with abstract murals. They were inspired by the murals Estampas de Guerrero by Arenal and the Mural Cuauhtémoc contra el mito by Siqueiros. The head sculpture weighs and is high. Iron sheets were used to sculpt the concrete. The head originally would have had a neck and shoulders, with channels to protect it from the accumulation of water. Inside the museum, there is a collection with the chronology of Juárez's life, as well as some works by Siqueiros, Diego Rivera, José Clemente Orozco and Rufino Tamayo. Its esplanade is open for cultural events and the roundabout has a size of .
Reception
Art critic said that the sculpture is "an exaltation to the patriotic sense of the liberals and their importance in the construction of modern Mexico". Writer Carlos Monsiváis considered it "guillotined par excellence, horrible and terrible". The head commonly appears on lists of the country's ugliest sculptures. In a 2017 poll, 27.76 percent of voters rated it the ugliest in the city. The head inspired the pictogram of the Guelatao metro station of the Mexico City Metro, which is the closest to the museum. Blogger Tamara De Anda named it one of the system's worst pictograms.
Notes
References
External links
1976 establishments in Mexico
Abstract art
Busts in Mexico
Colossal statues
Concrete sculptures in Mexico
Cultural depictions of Benito Juárez
Indigenismo in Mexico
Monuments and memorials in Mexico City
Murals in Mexico
Museums in Mexico City
Sculptures of Indigenous Mexicans
Sculptures of men in Mexico City | Museo Cabeza de Juárez | [
"Physics",
"Mathematics"
] | 698 | [
"Quantity",
"Colossal statues",
"Physical quantities",
"Size"
] |
69,177,254 | https://en.wikipedia.org/wiki/Energy%20Impact%20Center | The Energy Impact Center is an American research institute based in Washington, D.C. It primarily advocates for the expansion of nuclear power as a clean energy solution to climate change. The organization's research into nuclear power has led it to the development of projects like OPEN100, an open-source platform with blueprints for nuclear power plant design and construction. In 2020, the center spun out Last Energy, a commercial developer aimed at linking investors with agencies looking to build nuclear plants. The center is also responsible for the podcasts, Titans of Nuclear and Energy Impact. It was founded in 2017 by Bret Kugelmass.
History
The Energy Impact Center (EIC) was founded in Washington, D.C. by Bret Kugelmass in 2017. The goal at the organization's outset was to advocate for an increase in nuclear power to help reverse the effects of climate change by 2040. In 2017, Kugelmass began conducting interviews as head of EIC with experts in nuclear energy and related fields for a podcast called Titans of Nuclear. The podcast debuted in January 2018. Over the course of 2018 and 2019, Kugelmass and other members of the EIC team conducted around 1,500 interviews for the podcast and visited over 100 nuclear sites to compile research about the feasibility of nuclear power expansion.
In 2019, the center introduced the Nuclear Energy Grand Challenge, a prize competition that asked university students to develop business proposals for mitigating the cost, duration, and risks of power plant construction and maintenance. In February 2020, the EIC introduced two new entities: OPEN100 and Last Energy. The former is an open-source platform that aims to ease the design and construction process of nuclear power plants by providing freely-available blueprints. The latter is a for-profit startup that connects investors with agencies looking to develop nuclear power plants. Last Energy received $3 million in a funding round led by First Round Capital at the time of the announcement.
In 2021, EIC introduced a second podcast called Energy Impact that focuses on a broader range of energy-related topics. In July of that year, it was announced that Transcorp Energy in Nigeria had agreed to use EIC's OPEN100 model to construct the country's first nuclear power plants.
Projects
OPEN100
OPEN100 is an open-source platform that publishes blueprints for the design and construction of nuclear power plants. It also provides financing and maintenance details. The initial OPEN100 plans introduced in February 2020 called for a 100-megawatt pressurized water reactor that could be built in 18 months at a cost of $300 million (USD). Regulatory restrictions could increase those numbers in practice. OPEN100 was developed by EIC in partnership with the United States Department of Energy national laboratories and other collaborators, including Framatome, the Electric Power Research Institute, and the U.K.'s National Nuclear Laboratory. In July 2021, Nigeria's Transcorp Energy announced that it would develop nuclear power plants in the country using the OPEN100 model.
Nuclear Energy Grand Challenge
The Nuclear Energy Grand Challenge is a prize competition that was initially envisioned as a series of ongoing contests to develop proposals for mitigating the cost, duration, and risks of nuclear power plant construction and maintenance. The initial challenge, known as "Reimagining Nuclear Waste," took place at the University of Michigan in 2019 and 2020 and asked students to develop business proposals that offered new solutions for nuclear waste beyond indefinite storage. The winning team was awarded $17,000 for its proposal.
Podcasts
EIC produces two podcasts: Titans of Nuclear and Energy Impact. Titans of Nuclear was first launched in January 2018 and generally features one-on-one discussions with nuclear energy experts from various political, scientific, technological, and business backgrounds. The Energy Impact podcast was launched in March 2021 and features discussions on a broader range of energy-related topics. Both podcasts are primarily hosted by EIC managing director, Bret Kugelmass, but other EIC members serve as occasional co-hosts.
References
External links
Official website
OPEN100
Titans of Nuclear
Nuclear research institutes
Research institutes established in 2017
Non-profit organizations based in Washington, D.C.
Energy research institutes | Energy Impact Center | [
"Engineering"
] | 852 | [
"Nuclear research institutes",
"Energy research institutes",
"Nuclear organizations",
"Energy organizations"
] |
69,177,468 | https://en.wikipedia.org/wiki/Presbyosmia | Presbyosmia is the gradual degeneration of sense of smell due to ageing process, which occurs especially in those who are 70 years old or more. It is possibly due to loss of nerve endings in the nose, as well as reduced mucus production. Presbyosmia is less prevalent among elderly who are healthy, and who lack the risk factors for smell disorders. Other factors among elderly that can effect the sense of smell are medication use and some neurological disorders, in these cases the loss of smell can be much more noticeable. There is currently no established treatment for this condition.
References
Gerontology
Olfaction | Presbyosmia | [
"Biology"
] | 128 | [
"Gerontology"
] |
69,177,994 | https://en.wikipedia.org/wiki/Fantasy%20video%20game%20console | A fantasy video game console (or simply fantasy console) is an emulator for a fictitious video game console. In short, it aims to create the experience of retrogaming without the need to emulate a real console, allowing the developer to freely decide what specifications their fictional hardware will have.
One popular example of a fantasy console is the PICO-8, which was used as the platform for the original Celeste game. Though many fantasy consoles, such as the PICO-8, the TIC-80 and the Pixel Vision 8, use the Lua programming language, a variety of other languages, such as JavaScript and Python, are supported by other fantasy consoles. Even if two consoles use the same programming language, that doesn't mean they are compatible. There are often subtle differences in the syntax, and most notably in the API. There are some tools that aim to interconvert these console's cartridges automatically (including the scripts), but they are not perfect.
Another example is the Gigadrive, an imaginary revision of the Sega Genesis designed by M2, who also developed an emulator of this system. This console was given double VRAM, four more background layers (and Z-values in each layer), and sprites to archive 3D effects in patched Genesis games. These emulated games were sold in Nintendo 3DS under the label 3D Classics.
As of November 2021, fantasy consoles PICO-8 and TIC-80 are among the top 20 most used game development platforms on itch.io.
Definition
Joseph White, creator of the PICO-8, coined the term "fantasy console", and describes it as follows:
As developer Björn Ritzl puts it, fantasy consoles simulate the restricted hardware of an old system packaged into a user-friendly experience with integrated tools for asset creation and game logic programming.
See also
CHIP-8, a predecessor to fantasy consoles.
Picotron, a fantasy workstation developed as a successor of PICO-8
TIS-100, a video game where the player programs a fictional 1970s computer.
References
Fantasy console | Fantasy video game console | [
"Technology"
] | 425 | [
"Computing terminology",
"Video game terminology"
] |
69,178,228 | https://en.wikipedia.org/wiki/Garrod%20Lecture%20and%20Medal | The Garrod Lecture and Medal is an award presented by the British Society for Antimicrobial Chemotherapy. It was established in 1982 and named for L. P. Garrod. The medal is made of silver by the Birmingham Mint. The recipient of the award is considered by the society as having international authority in the field of antimicrobial chemotherapy. They are invited to deliver an accompanying lecture and receive honorary membership of the Society.
Recipients
References
British lecture series
Lists of physicians
Medicine awards
Medical education in the United Kingdom
Medical lecture series
1982 establishments in the United Kingdom
Recurring events established in 1982
Microbiology | Garrod Lecture and Medal | [
"Chemistry",
"Technology",
"Biology"
] | 123 | [
"Science and technology awards",
"Microbiology",
"Medicine awards",
"Microscopy"
] |
69,178,340 | https://en.wikipedia.org/wiki/Creator%20economy | The creator economy or also known as creator marketing and influencer economy, is a software-driven economy that is built around creators who produce and distribute content, products, or services directly to their audience, leveraging social media platforms and AI tools. These creators - who may include social media influencers, YouTubers, bloggers, artists, podcasters, and even independent professionals - generate revenue from their creations through a variety of monetization strategies, including advertising, sponsorships, product sales, crowdfunding, and subscription-based services. According to Goldman Sachs Research, the ongoing growth of the creator economy will likely benefit companies that possess a combination of factors, including a large global user base, access to substantial capital, robust AI-powered recommendation engines, versatile monetization tools, comprehensive data analytics, and integrated e-commerce options. Examples of creator economy software platforms include YouTube, TikTok, WFCN, Instagram, Facebook, Twitch, Spotify, Substack, OnlyFans and Patreon.
History
In 1997, Stanford University's Paul Saffo suggested that the creator economy first came into being in 1997 as the "new economy". Early creators in that economy worked with animations and illustrations, but at the time there was no available marketplace infrastructure to enable them to generate revenue.
The term "creator" was coined by YouTube in 2011 to be used instead of "YouTube star", an expression that at the time could only apply to famous individuals on the platform. The term has since become omnipresent and is used to describe anyone creating any form of online content.
The creator economy consists of approximately 50 million content creators, and there are just over 2 million who are able to make a career of it. The biggest names are those such as TikTok star Charli D'Amelio, PewDiePie and Addison Rae.
A number of platforms such as TikTok, Snapchat, YouTube, WFCN, Tiki and Facebook have set up funds with which to pay creators.
Criticism
The large majority of content creators derive no monetary gain for their creations, with most of the benefits accruing to the platforms who can make significant revenues from their uploads. As few as 0.1% of creators are able to earn a living through their channels.
See also
Content creation
Content intelligence
Content marketing
Cultural technology
Hype (marketing)
Influence-for-hire
Influencer marketing
Social commerce
Social media marketing
Viral marketing
References
Social media
Information Age | Creator economy | [
"Technology"
] | 507 | [
"Information Age",
"Computing and society",
"Social media"
] |
69,179,672 | https://en.wikipedia.org/wiki/Microsoft%20Loop | Microsoft Loop is an online collaborative workspace developed by Microsoft that offers a variety of features to help users gather, organize, and build notes, ideas, and projects.
History
Loop was officially announced on 2 November 2021 as an addition to Microsoft 365 suite of apps.
Functions
According to The Verge, Loop provides "blocks of collaborative text or content that can live independently and be copied, pasted, and shared freely."
Microsoft Loop comes with templates for meetings, project planning, and personal tasks, and offers integration with other Microsoft and third-party tools and services. It supports a maximum of 50 users editing a workspace simultaneously.
Similar to Notion, it includes workspaces and pages where users can import and organize tasks, projects, and documents.
However, it also uses shareable components that allow content from Loop to be turned into a real-time block of content that can be pasted into Teams, Outlook, Word and Whiteboard. It also features the ability to use Microsoft Copilot.
References
External links
Loop | Microsoft Loop | [
"Technology"
] | 207 | [
"Computing stubs",
"Collaborative real-time editors",
"Software stubs"
] |
69,183,062 | https://en.wikipedia.org/wiki/Polycoccum%20anatolicum | Polycoccum anatolicum is a species of lichenicolous fungus in the family Polycoccaceae. It was described as a new species by Mehmet Gökhan Halici and Hatice Esra Akgül in 2013. The type specimen was collected growing on the thallus of the dust lichen Lepraria incana, which itself was growing on the trunk on a Prunus species in western Turkey at an altitude of . The specific epithet refers to the type locality in Anatolia.
The fungus causes mild bleaching on infected parts of the surface of the host. It is the only species of Polycoccum known to infect Lepraria. Polycoccum dzieduszyckii is morphologically similar, but can be distinguished from P. anatolicum by its eight-spored asci and its growth on Verrucaria.
References
Trypetheliales
Taxa described in 2013
Fungi of Asia
Lichenicolous fungi
Fungus species | Polycoccum anatolicum | [
"Biology"
] | 203 | [
"Fungi",
"Fungus species"
] |
69,185,988 | https://en.wikipedia.org/wiki/Mars%3A%20The%20Secret%20Science | Mars: The Secret Science is a documentary science television series narrated by David O'Brien which the Science Channel broadcast in 2016 and 2018.
Content
Mars: The Secret Science looks at how scientists and modern explorers are working to get humans to Mars. The series both explores Mars and chronicles how the National Aeronautics and Space Administration (NASA) is building rockets and spacecraft to carry astronauts there and how technology visionaries are designing Martian colonies. The series also looks at issues such as the design of spacesuits for use on Mars and of the vehicles humans will need for transportation there.
In 2018, the Science Channel broadcast specials under the title Mars: The Secret Science, some of which consisted entirely of segments broadcast previously in episodes of Mars: The Secret Science, How the Universe Works, The Planets and Beyond, or Strip the Cosmos .
Episode list
Season 1 (2016)
SOURCES ihavenotv.com Mars: The Secret ScienceTV Maze Mars: The Secret Science Episode List
Specials (2018)
SOURCES TV Maze Mysteries on the Red PlanetTV Maze NASA's Mission to Mars: InSight Lander
See also
Alien Planet
Cosmos: A Spacetime Odyssey
Extreme Universe
How the Universe Works
Into the Universe with Stephen Hawking
Killers of the Cosmos
Space's Deepest Secrets
Strip the Cosmos
Through the Wormhole
The Universe
References
External links
Mars - The Secret Science - Episode 1 of 5 on YouTube
Mars - The Secret Science excerpt "Scientists Think Mars Once Had Water. So What Happened to It?" on YouTube
Mars - The Secret Science excerpt "Here's How Scientists Will Measure Quakes on Mars" on YouTube
Mars - The Secret Science excerpt "Would You Take the One Way Trip to Mars?" on YouTube
Mars - The Secret Science excerpt "SpaceX Wants to Send You To Mars. Here's How They Plan to Do It" on YouTube
Mars - The Secret Science excerpt "Testing the Curiosity Rover on Earth" on YouTube
Mars - The Secret Science excerpt "Looking For Ancient Martian Lakes" on YouTube
Mars - The Secret Science excerpt "Something in the Martian Sand is Explosive!" on YouTube
Mars - The Secret Science excerpt "This is How NASA Guides Robots Around Mars" on YouTube
Mars - The Secret Science excerpt "First Step In Training For Work on Mars: Go Underwater" on YouTube
Mars - The Secret Science excerpt "Engineers Have Already Built Vehicles to Drive on the Martian Surface" on YouTube
Mars - The Secret Science excerpt "Scientists Are Designing the Spacesuits We'll Wear on Mars" on YouTube
2016 American television series debuts
2018 American television series endings
2010s American documentary television series
Documentary television series about astronomy
Science Channel original programming
Works about Mars | Mars: The Secret Science | [
"Astronomy"
] | 524 | [
"Documentary television series about astronomy",
"Works about astronomy"
] |
69,186,062 | https://en.wikipedia.org/wiki/Oxepanoprolinamide | Oxepanoprolinamides are a class of antibiotics. They include iboxamycin. These drugs are fully synthetic. The molecules contain the aminooctose component of clindamycin. They were developed by Andrew G. Myers and Yury S. Polikanov. The structure contains an oxepane (a seven-membered ring compound with oxygen) and a proline, with an amide group that increases rigidity.
Oxepanoprolinamides function by insertion into bacterial ribosomes. They overcome a type of antibiotic resistance to clindamycin based on Erm and Cfr ribosomal RNA methyltransferase enzymes.
References
Antibiotics
Pyrrolidines
Oxepanes
Thioethers | Oxepanoprolinamide | [
"Biology"
] | 153 | [
"Antibiotics",
"Biocides",
"Biotechnology products"
] |
69,187,225 | https://en.wikipedia.org/wiki/The%20Planets%20and%20Beyond | The Planets, retitled The Planets and Beyond for its second season, is a documentary television series produced by the Science Channel that aired from 2017 to 2019. It explores the planets and of the Solar System, exoplanets, and other astronomical objects.
Format
Former astronaut Mike Massimino hosts the show, appearing briefly to introduce each segment of each episode, and Erik Dellums narrates the series. During its first season, titled The Planets, the series focused on planets exclusively except for a single episode which studied the Moon. Retitled The Planets and Beyond, the series expanded its focus during its second season to include other types of astronomical objects. The Science Channel also broadcast The Planets and The Planets and Beyond specials, some of them made up of original footage and others of segments broadcast previously on The Planets, The Planets and Beyond, How the Universe Works, Space's Deepest Secrets, and Strip the Cosmos.
Episode list
Season 1 – The Planets (2017)
Season 2 – The Planets and Beyond (2018)
Special — The Planets and Beyond (2019)
References
External links
Science Channel's The Planets, "Venus Alien Evidence" on YouTube
2017 American television series debuts
2019 American television series endings
2010s American documentary television series
Documentary television series about astronomy
Science Channel original programming | The Planets and Beyond | [
"Astronomy"
] | 256 | [
"Documentary television series about astronomy",
"Works about astronomy"
] |
69,187,271 | https://en.wikipedia.org/wiki/PETREL | PETREL (Platform for Extra and Terrestrial Remote Examination with LCTF) is a technology demonstration satellite being developed by Tokyo Institute of Technology. The microsatellite is equipped with a multispectral camera, which will be used to carry out two distinct missions. One mission is to survey the sky in ultraviolet wavelengths for the field of time-domain astronomy, and the other is to conduct spectroscopic observations of the Earth. PETREL was originally planned to be launched on a Epsilon rocket flight in 2022 along with the rest of JAXA's Innovative Satellite Technology Demonstration-3 mission satellites, but was not launched. As of September 2024, PETREL is scheduled to be launched during fiscal year 2025 on the first H3-30 test flight.
Overview
PETREL's role differs depending on its position in orbit: while inside Earth's shadow it will conduct astronomical observations, and while outside it will function as an Earth observation satellite.
PETREL will conduct wide field observations in ultraviolet, which will work in tandem with ground-based observatories to study time-domain multi-messenger astronomy. PETREL is a pathfinder for the ULTRASAT mission.
As an Earth observation satellite, PETREL will perform multispectral observation of both the land and seas to acquire data for use in agriculture and aquaculture. PETREL's ocean observation will measure the level of plankton and nutrients in the waters, which the aquaculture industry will utilize to help ensure a stable amount of catches.
See also
References
External links
Project PETREL - Tokyo Institute of Technology
PETREL
2025 in spaceflight
Proposed spacecraft
Satellites of Japan
Space telescopes
Ultraviolet telescopes | PETREL | [
"Astronomy"
] | 334 | [
"Space telescopes"
] |
69,187,512 | https://en.wikipedia.org/wiki/Anand%20Pillay | Anand Pillay (born 7 May 1951) is a British mathematician and logician working in model theory and its applications in algebra and number theory.
Biography
Pillay studied as an undergraduate at the University of Oxford, obtaining a Bachelor in Mathematics and Philosophy in 1973 at Balliol College. At the University of London, he received his master's degree in mathematics in 1974 and his PhD in 1978 with Wilfrid Hodges at Bedford College, titled Gaifman Operations, Minimal Models, and the Number of Countable Models. In 1978, he was a Royal Society Fellow and visiting scientist at CNRS at Paris Diderot University. After teaching at the University of Manchester starting in 1981 and at McGill University in Canada, he joined the University of Notre Dame as an assistant professor in 1983, where he became an associate professor in 1986 and a full professor in 1988. From 1996 to 2006, he was Swanlund Professor at the University of Illinois Urbana-Champaign, where he is now Professor Emeritus. Since 2005, he has been the Chair of Mathematical Logic at the University of Leeds. He also held positions as a visiting scholar at the Fields Institute in Toronto, at the Mathematical Sciences Research Institute in Berkeley, and at the Isaac Newton Institute in Cambridge.
Career
Pillay's dissertation work concerned the number of countable models of countable theories; under the influence of the Paris school of model theory, he also worked on stability theory. Later, he dealt with applications of model theory in other areas of mathematics, including Nash manifolds and groups, algebraic theory of differential equations and differential algebra, classification of compact complex manifolds, and diophantine geometry.
Pillay was an invited speaker at the International Congress of Mathematicians in Zürich in 1994. In 2009 he was invited to present the Tarski Lectures, titled Compact Spaces, Definability, and Measures, in Model Theory. His three lectures were titled "The Logic Topology", "Lie Groups from Nonstandard Models", and "Measures and Domination". In 2001, he received the Humboldt Foundation's research award, and was also a Humboldt Fellow at the University of Kiel in 1988 and at the University of Freiburg in 1992. In 2011, he gave the Gödel Lecture. He is a Fellow of the American Mathematical Society.
Selected works
An introduction to stability theory (Oxford Logic Guides 8). Clarendon Press, Oxford 1983, ISBN 0-19-853186-9.
Geometric Stability Theory (Oxford Logic Guides 32). Clarendon Press, Oxford 1996, ISBN 0-19-853437-X.
with David Marker and Margit Messmer: Model theory of fields (Lecture Notes in Logic 5). Springer, Berlin. 1996, ISBN 3-540-60741-2.
Model Theory and Diophantine Geometry. In: Bulletin of the American Mathematical Society. Vol. 34, No. 4, 1997, pp. 405–422, .
Model Theory. In: Notices of the American Mathematical Society. Vol. 47, No. 11, 2000, pp. 1373–1381.
with Deidre Haskell and Charles Steinhorn (ed.): Model theory, algebra and geometry (Mathematical Sciences Research Institute Publications 39). Cambridge University Press, Cambridge, 2000, ISBN 0-521-78068-3.
References
External links
Homepage at University of Notre Dame
Short Biography
Living people
1951 births
British mathematicians
Model theorists | Anand Pillay | [
"Mathematics"
] | 689 | [
"Model theorists",
"Model theory"
] |
69,188,421 | https://en.wikipedia.org/wiki/Zytek%20ZG348 | The Zytek ZG348 engine is a 3.4-litre, normally-aspirated, V8 racing engine, developed and produced by Zytek for sports car racing. The ZG348's rev-limit was about 10,000 rpm, and produces its power output of @ 9,500 rpm, and peak torque of @ 8,500 rpm.
Applications
Reynard 02S
Ginetta G50
Ginetta-Zytek GZ09S
References
Engines by model
Gasoline engines by model
Zytek engines
V8 engines | Zytek ZG348 | [
"Technology"
] | 114 | [
"Engines",
"Engines by model"
] |
69,188,655 | https://en.wikipedia.org/wiki/Zytek%20ZJ458 | The Zytek ZJ458 engine is a 4.5-litre, normally-aspirated, V8 racing engine, developed and produced by Zytek for sports car racing. The ZJ458's rev-limit was about 10,000 rpm, and produces its power output of @ 9,000 rpm, and peak torque of @ 7,500 rpm.
Applications
Ginetta-Zytek GZ09S
Zytek Z11SN
References
Engines by model
Gasoline engines by model
Zytek engines
V8 engines | Zytek ZJ458 | [
"Technology"
] | 113 | [
"Engines",
"Engines by model"
] |
69,189,445 | https://en.wikipedia.org/wiki/Mercedes-Benz%20M196%20engine | The Mercedes-Benz M196 engine is a naturally-aspirated, straight-8, racing engine, designed, developed, and produced by Daimler-Benz; and used in both sports car racing and Formula One racing, between 1954 and 1955. Daimler-Benz made two versions of the engine, the M 196 R, displacing 2.5 litres, and the M 196 S, displacing 3.0 litres.
Mercedes pulled out of all motorsports after the 1955 Le Mans disaster. This was their last Formula One engine, and Mercedes did not return to motorsport as an engine manufacturer until , when they supplied engines to the Sauber Formula One team.
M 196 R
The new 1954 Formula One rules allowed a choice of naturally aspirated engines – up to 2.5 litres or 0.75 litres supercharged. The expected target range for competitive engines was .
By its introduction at the 1954 French GP the (76.0×68.8 mm) desmodromic valves straight 8 M 196 R delivered . The M 196 was the only F1 engine with direct fuel injection, giving it a considerable advantage over the other carburetted engines.
For the 1955 season, Daimler-Benz improved its M 196 R engine by reducing the intake manifold length, increasing the engine power slightly to .
The latest iteration of the 2.5-litre unit eventually had a compression in the range of ε=12.0…12.5, produced up to at 8500/min, and delivered a maximum torque of at 6450/min, equivalent to a BMEP of .
M 196 S
For the W 196 S race car, the M 196 engine was bored and stroked to 78 mm each (78.0 × 78.0 mm), and reduced in compression from ε=12 to about ε=9. The latter allowed using standardised petrol (98 RON) instead of high-octane race fuel required for the M 196 R. The M 196 S has a power output of at 7,000 rpm, and produces a maximum torque of at 5,950 rpm. This is equivalent to a BMEP of .
The M 196 S is canted to the right at a 53° angle. It has two four-cylinder banks made of silumin with chromium-coated aluminium cylinder sleeves. Unlike typical car engines, the M 196 S has a crankshaft consisting of two Hirth joint halves with centre torque take-off. The silumin cylinder heads are crossflow heads and cast together with the cylinder banks (i. e. block and head are a single cast piece). Daimler-Benz fitted the engine with a dry-sump lubrication system, water cooling, and a direct fuel injection system. The ignition system is a traditional magneto system.
Applications
Mercedes-Benz W196
Mercedes-Benz 300 SLR
References
Mercedes-Benz engines
Straight-eight engines
Formula One engines
Engines by model
Gasoline engines by model | Mercedes-Benz M196 engine | [
"Technology"
] | 606 | [
"Engines",
"Engines by model"
] |
61,286,539 | https://en.wikipedia.org/wiki/Gretchen%20Kalonji | Gretchen Lynn Kalonji (born April 13, 1953) is an American materials scientist and academic administrator. She is dean of Sichuan University-Hong Kong Polytechnic University Institute for Disaster Management and Reconstruction. Kalonji was previously the assistant director-general for natural sciences at UNESCO. She was the Kyocera Professor of Materials Science at University of Washington and an associate professor at Massachusetts Institute of Technology.
Early life and education
Kalonji was born April 13, 1953, in Chicago, Illinois to journalist parents and, after the age of seven, grew up moving between India, Hong Kong, Thailand, and East Africa. She was kicked out of school twice in Hong Kong during the 1967 leftist riots in which she participated in the siege of the U.S. embassy and protests against the Vietnam War. She was also kicked out of school in east Africa and eventually began working in metallurgy and learned practical skills in welding, milling, turning, elementary design, and drafting. Kalonji planned on applying for Kenyan citizenship after completing schooling in the United States. She enrolled at University of Maryland, College Park as a special student because she had not completed a high school diploma. She took courses in chemistry and materials science. After meeting Julia McCormick, the admissions director at MIT, Kalonji began undergraduate coursework at Massachusetts Institute of Technology in February 1979. Kalonji earned a B.Sc. in May 1980 and a Ph.D. in 1982 in materials science and engineering. She completed her dissertation in five semesters after her B.S. under the direction of Samuel M. Allen in 1982. She completed a cooperative internship at National Institute of Standards and Technology (then National Bureau of Standards) under mentor John W. Cahn. Kalonji's future research was influenced by courses she took with and Bernie Wuensch.
Career
Kalonji was an assistant and associate professor in the MIT department of materials science and engineering from 1982 to 1990. At MIT, Kalonji was the U.S. co-director of the Computer Science and Electronics Program at Solomon Mahlangu Freedom College. While at MIT, Kalonji was active in the Anti-Apartheid Movement. Kalonji and Willard Johnson, a professor of political science and one of the founders of TransAfrica, organized a faculty disinvestment from South Africa campaign, led demonstrations, and facilitated staff meetings. In 1990, she became the Kyocera Professor of Materials Science at University of Washington. Kalonji joined the University of California as the director of international strategy development from 2005 to 2009 and the director of system-wide research development from 2009 to 2010. In 2006, she became a professor in the department of electrical engineering at University of California, Santa Cruz. On July 1, 2010, Kalonji became the assistant director-general for natural sciences at UNESCO. She is the first woman to hold this position at UNESCO. Kalonji is the dean of Sichuan University-Hong Kong Polytechnic University Institute for Disaster Management and Reconstruction and a strategic advisory of institutional development at SCU.
Personal life
Kalonji sued MIT in 1994, alleging that she was denied tenure because of sexual discrimination. Several years later, the lawsuit was settled with undisclosed payments and the establishment of a project to encourage women and minorities to seek faculty positions.
In a September 1995 interview, Kalonji reported she lived in Seattle with her 3 sons.
Kalonji is a member of the LGBT community. She resided in downtown San Francisco with her partner of more than ten years, Denice Denton, a professor of electrical engineering and academic administrator. On June 24, 2006, one day following Denton's discharge from the Langley Porter Psychiatric Institute where she had been treated for depression, Denton leapt 33 stories to her death from The Paramount, a high-rise in which she shared an apartment with Kalonji.
In August 2007, Kalonji filed a lawsuit against Denton's estate seeking $2.25 million. Kalonji claimed Denton's failure to revise her will or name Kalonji as a beneficiary to her UC life insurance policy was inadvertent and a violation of their oral agreement. In July 2009, a probate judge awarded Kalonji one half of a Canadian vacation home that the coupled had shared while giving the rest of Denton's estate to Denton's parents and siblings.
Award and honors
In 1994, Kalonji won the George Westinghouse Award (ASEE). She is a Fellow of the American Association for the Advancement of Science.
References
Living people
1953 births
Fellows of the American Association for the Advancement of Science
MIT School of Engineering alumni
MIT School of Engineering faculty
University of Washington faculty
UNESCO officials
20th-century American scientists
21st-century American scientists
20th-century American women scientists
21st-century American women scientists
Women deans (academic)
Academic staff of Sichuan University
Academic staff of Hong Kong Polytechnic University
University of California, Santa Cruz faculty
American lesbians
American LGBTQ scientists
American materials scientists
Women materials scientists and engineers
American expatriate academics
LGBTQ people from Illinois
Scientists from Chicago
American women academics
21st-century American LGBTQ people | Gretchen Kalonji | [
"Materials_science",
"Technology"
] | 1,036 | [
"Women materials scientists and engineers",
"Materials scientists and engineers",
"Women in science and technology"
] |
61,287,448 | https://en.wikipedia.org/wiki/Prachee%20Avasthi | Prachee Avasthi (born 1979) is a Professor of Anatomy and Cell Biology and Science Communicator at Dartmouth College and a co-founder, chief scientific advisor, and incoming CSO at Arcadia Science in Berkeley, California. She works on upwardly motile Chlamydomonas reinhardtii and is on the Board of Directors of eLife.
Early life and education
Avasthi studied integrative physiology at the University of Illinois at Urbana–Champaign. During her undergraduate program she worked on insect classification and synaptic plasticity. She became more interested in the brain, and earned her PhD in neuroscience under the supervision of Wolfgang Baehr at the University of Utah. During her doctoral studies she investigated how cilia help our eye's photoreceptors detect light. She was a postdoctoral researcher with Wallace Marshall at the University of California, San Francisco. Here she began work on Chlamydomonas reinhardtii, a model organism for studying cilia. Cilia function requires normal cilia length and motility, and Avasthi identified that the dopamine binding G protein-coupled receptors (GPCRs) were the most regularly involved with flagellar length regulation.
Research and career
Avasthi uses Chlamydomonas reinhardtii, a unicellular green alga, to investigate the assembly of cilia. She was particularly interested in the cellular machinery needed to maintain cilia, and used small molecule chemical inhibitors to identify important features in ciliary transport. Avasthi found that actin, a cytoskeleton protein, was required for intraflagellar transport (IFT) regulation in Chlamydomonas reinhardtii. The actin is recruits IFT to basal bodies during the elongation of flagella; and without actin the flagellar length is lost. She saw the same impacts using a myosin inhibitor, which suggests that actin may use a myosin pathway.
In 2015 Avasthi started her own research group at the University of Kansas Medical Center, which is supported by the National Institutes of Health. She combines chemical biology and biochemistry with genetics to understand the mechanisms that regulate assembly of the cilium. In 2018 she was awarded an NIH R35 Outstanding Investigator Award.
Academic service
Avasthi is enthusiastic about reforming scientific research culture, helping early career researchers set up their own laboratories. She launched New PI Slack, an online space for over a thousand new Principal investigators to share notes and ideas. Avasthi supports preprints and the reform of scientific publishing, and is on the Board of Directors of eLife and ASAPbio. In her laboratory she leads a preprint journal club, where members of her group read and review new material, providing feedback to authors.
References
Open access activists
Women biochemists
Women physiologists
University of Kansas faculty
University of Utah alumni
1979 births
Living people
University of Illinois College of Liberal Arts and Sciences alumni | Prachee Avasthi | [
"Chemistry"
] | 606 | [
"Biochemists",
"Women biochemists"
] |
61,287,985 | https://en.wikipedia.org/wiki/Assembly%20line%20feeding%20problem | The assembly line feeding problem (abbr. ALFP) describes a problem in operations management concerned with finding the optimal way of feeding parts to assembly stations. For this, various cost elements may be taken into account and every part is assigned to a policy, i.e., a way of feeding parts to an assembly line. The most common policies are:
Line stocking (also: line side stocking, pallet to work-station, etc)
Boxed-supply (also: Kanban, batch supply, etc.)
Sequencing
Stationary kitting (also: indirect supply, trolley to workstation)
Traveling kitting (also: indirect supply, kit to assembly line)
These policies differ with respect to the way parts are brought to the line as well as in the way parts are handled before they are brought to the line. E.g., in line stocking, parts are brought to the line directly in the way they are stored in the warehouse. In the other policies, quantities are reduced (boxed supply) and different part variants are sorted in the order of demand (sequencing, stationary, and traveling kitting).
History
The problem was formally introduced by Bozer and McGinnis in 1992 by means of a descriptive cost model. Since then, many contributions have been made in both, quantitative and qualitative manners. E.g., a more qualitative contribution is done by Hua and Johnson investigating important aspects of the problem, whereas more recent contributions focus rather on quantitative aspects and use mathematical optimization to solve this assignment problem to optimality
Mathematical problem statement
This model minimizes the costs when assigning all parts (index:i) to a feeding policy (index:p) at all stations (index:s) , if there is a demand for a part at a station . Using a certain policy at a station incurs some cost as well as some other costs are incurred when a policy is used at any station, .
All assembly line feeding problems of this type have been proven to be NP-hard
References
Manufacturing
Production economics | Assembly line feeding problem | [
"Engineering"
] | 414 | [
"Manufacturing",
"Mechanical engineering"
] |
61,288,146 | https://en.wikipedia.org/wiki/Hokovirus | Hokovirus (HokV) is a genus of giant double-stranded DNA-containing viruses (NCLDV). This genus was detected during the analysis of metagenome samples of bottom sediments of reservoirs at the wastewater treatment plant in Klosterneuburg, Austria. New Klosneuvirus (KNV), Catovirus and Indivirus genera (all found in these sewage waters) were also described together with Hokovirus, building up a putative virus subfamily Klosneuvirinae (Klosneuviruses) with KNV as type genus.
Hokovirus has a large genome of 1.33 million base pairs (881 gene families). This is the third largest genome among known Klosneuviruses after KNV (1.57 million base pairs, 1272 gene families) and Catovirus. GC content is 21.4 %
Classification of metagenome, made by analyzing 18S rRNA indicate that their hosts are relate to the simple Cercozoa.
Phylogenetic tree topology of Mimiviridae is still under discussion. Some authors (CNS 2018) like to put Klosneuviruses together with Cafeteria roenbergensis virus (CroV) and Bodo saltans virus (BsV) into a tentative subfamily called Aquavirinae. Another proposal is to put them together with Mimiviruses into a subfamily Megavirinae.
See also
Nucleocytoplasmic large DNA viruses
Girus
Mimiviridae
References
Further reading
Mitch Leslie: Giant viruses found in Austrian sewage fuel debate over potential fourth domain of life. In: Science. 5. April 2017, doi:10.1126/science.aal1005.
Virus genera
Mimiviridae
Unaccepted virus taxa | Hokovirus | [
"Biology"
] | 361 | [
"Biological hypotheses",
"Unaccepted virus taxa",
"Controversial taxa"
] |
61,288,762 | https://en.wikipedia.org/wiki/U-CARE | u-CARE otherwise known as user-friendly Comprehensive Antibiotic resistance Repository of Escherichia coli is a database focused on the documentation of multi-drug resistant Escherichia coli (E.coli). This database aims to provide a tool that is easily accessible to researchers unfamiliar with bioinformatics and to medical practitioners as a reference for which antibiotic to use/not use in the treatment of an E.coli infection. u-CARE is manually curated with 52 antibiotics, 107 genes, transcription factors, and SNP. Information provided include resistance mechanism for the gene and summary, chemical description, and structural descriptions for the antibiotic. On the antibiotic page, there is an external link linking to public databases like GO, CDD, Ecocyc, DEG, KEGG, DrugBank, Pubchem and Uniprot. u-CARE can be accessed at http://www.e-bioinformatics.net/ucare..
See also
Antimicrobial Resistance databases
References
Antimicrobial resistance organizations
Biological databases | U-CARE | [
"Biology"
] | 217 | [
"Bioinformatics",
"Biological databases"
] |
61,289,418 | https://en.wikipedia.org/wiki/Rhodium%20trifluoride | Rhodium(III) fluoride or rhodium trifluoride is the inorganic compound with the formula RhF3. It is a red-brown, diamagnetic solid.
Synthesis and structure
The compound is prepared by fluorination of rhodium trichloride:
It can also be obtained by direct combination of the elements:
Anhydrous is insoluble in water and does not react with it, but the hydrates and can be prepared by adding hydrofluoric acid to aqueous rhodium(III) solutions.
According to X-ray crystallography, the compound adopts the same structure as vanadium trifluoride, wherein the metal achieves octahedral coordination geometry.
References
Fluorides
Platinum group halides
Rhodium(III) compounds | Rhodium trifluoride | [
"Chemistry"
] | 173 | [
"Fluorides",
"Salts"
] |
61,290,269 | https://en.wikipedia.org/wiki/Melanie%20Perkins | Melanie Perkins (born 1987) is an Australian technology entrepreneur, who is the co-founder and chief executive officer of Canva. She owns 18% of the company.
Perkins is one of the youngest female CEOs of a tech start-up valued over 1 billion. , Perkins was one of Australia's richest women with an estimated net worth of US$4.4 billion..
In 2023, she ranked 89th in Forbes list of "World's 100 most powerful women" and 92nd in Fortune's list of Most Powerful Women.
Early life
Melanie Perkins was born in 1987 in Perth, Western Australia. She is the daughter of an Australian-born teacher and a Malaysian engineer of Filipino and Sri Lankan descent. She attended Sacred Heart College, a secondary school located in the northern Perth suburb of Sorrento. In high school, Perkins had aspirations of becoming a professional figure skater and would routinely wake up at 4:30 am to train. By the age of fourteen, she had started her first business, selling handmade scarves at shops and markets throughout Perth. She credits this experience with developing her entrepreneurial drive as ‘she never forgot the freedom and excitement from building a business.’
After high school, Perkins enrolled at The University of Western Australia, majoring in communications, psychology and commerce. At this time, Perkins was also a private tutor for students learning graphic design. She noticed the difficulties students had in learning design programs such as Adobe Photoshop: it would often take students a semester at university to be introduced to basic features of these complex design programs. Perkins thought there was a business opportunity in making the design process easier. Her idea was to make a design platform where no technical experience was required. She dropped out of university at age 19 to pursue her first business with Cliff Obrecht, Fusion Books.
Career
Fusion Books
Fusion Books was founded by Perkins and Obrecht in 2007. Fusion Books allowed students to design their own school yearbooks by using a simple drag-and-drop tool equipped with a library of design templates that could be populated with photos, illustrations, and fonts. Originally, Perkins wanted to develop software that made the entire design process easier but due to the competition with large companies and her lack of resources, she concluded ‘it did not seem the logical thing to do’. Perkins's mother was a teacher who would also co-ordinate the school yearbook. Perkins saw how much time was required to design a yearbook and thought the high level of consumer friction would make yearbooks a good niche to test the idea for Canva.
Started in the Duncraig living room of Perkins's mother, Obrecht would cold call schools in an attempt to get new clients for Fusion Books. Their parents would often help with printing the yearbooks. Over five years, Fusion Books grew into the largest yearbook company in Australia and expanded into France and New Zealand.
Formation of Canva
Perkins and Obrecht were originally based in Perth. Perkins claims that she was rejected by over 100 local investors in Perth.
In 2011, prominent investor, Bill Tai visited Perth to judge a start-up competition. Perkins and Obrecht pitched Tai the initial idea for Canva over dinner. There were also other venture capitalists present including Rick Baker from Blackbird Ventures. They received no funding but became regular fixtures at gatherings hosted by Tai for investors and start-up founders. Some of these gatherings took place in Silicon Valley where Perkins and Obrecht met Lars Rasmussen, co-founder of Google Maps. He expressed interest in the idea but told the founders to ‘put everything on hold’ until they found a tech team of the calibre required. Rasmussen then became the tech adviser to the business, where he introduced Perkins and Obrecht to Cameron Adams, an ex-Google employee with relevant technical expertise. Adams was initially not interested in joining the business as he was starting his own business called fluent.io, software attempting to disrupt email. Adams was in Silicon Valley trying to raise funds for his start-up when Perkins sent him another email asking if he wanted to join the business. After that email, he agreed to join Canva, becoming its third founder and chief product officer.
Perkins is the CEO of one of the few ‘unicorn’ start-ups that are profitable. In Nov. 2023, Forbes estimated her net worth at $ 3.6 bln. She remained CEO of Canva, and owned around 18 % of the company. She was named to the Financial Review Rich List of 2023.
Women in start-ups
Controversy surrounds the gender disparity in the technology industry as well as amongst start-ups, with one in four start-ups founded by a woman. Perkins is amongst the 2 percent of female CEOs of venture-backed companies. She wrote an article for people who feel like 'they are on the outside' and discussed her journey as a young entrepreneur in order to encourage people from diverse backgrounds to pursue big dreams and concentrate on their goals. Perkins has implemented policies at Canva that eliminate bias in the hiring process, that has resulted in Canva obtaining 41 percent female representation, significantly higher than the industry average of 28 percent.
Personal life
Perkins took an interest in kite surfing when she discovered many prominent venture capitalists use this as a way to network with founders. She would regularly kite-surf with venture capitalist Bill Tai. Perkins has also travelled the world extensively and credits a trip to India as a life-changing experience.
In 2019, Obrecht proposed to Perkins on a holiday in Turkey's backpacker-friendly Cappadocia region. The engagement ring was $30. The couple have been critical of materialism, with Obrecht stating, ‘what is the point of hoarding stuff’. They have expressed a desire to donate most of their fortune to charity. Perkins and Obrecht married in January 2021 on Rottnest Island. Later that year, they joined the Giving Pledge, committing at least half of their fortune to philanthropic purposes.
Net worth
In 2020 Forbes named Perkins as one of the world's "Top Under 30 of the Decade". Perkins first appeared on The Australian Financial Review Rich List in 2020 with a net worth of 3.43 billion. , The Australian Financial Review assessed her and Obrecht's joint net worth as 13.18 billion, on the 2023 Rich List; making them the ninth wealthiest Australians. As of 31 January 2022, Forbes estimated Perkins' personal net worth at A$9.21 billion (US$6.5bn).
Notes
: Perkins' net worth is assessed in Financial Review Rich List as being held jointly with her spouse and business partner, Cliff Obrecht.
References
External links
Living people
1987 births
Australian billionaires
Australian company founders
Australian people of Filipino descent
Australian people of Malaysian descent
Australian people of Sri Lankan descent
21st-century Australian businesswomen
21st-century Australian businesspeople
Australian women chief executives
Australian women company founders
Female billionaires
Businesspeople from Perth, Western Australia
Technology company founders | Melanie Perkins | [
"Technology"
] | 1,416 | [
"Lists of people in STEM fields",
"Proprietary technology salespersons"
] |
61,290,491 | https://en.wikipedia.org/wiki/Thallium%20trifluoride | Thallium trifluoride is the inorganic compound with the formula TlF3. It is a white solid. Aside from being one of two thallium fluorides, the compound is only of theoretical interest. It adopts the same structure as bismuth trifluoride, featuring eight-coordinate Tl(III) centers. Some evidence exists for a second polymorph.
References
Fluorides
Metal halides
Thallium(III) compounds | Thallium trifluoride | [
"Chemistry"
] | 98 | [
"Inorganic compounds",
"Fluorides",
"Metal halides",
"Salts"
] |
61,290,643 | https://en.wikipedia.org/wiki/Porsche%20flat-eight%20engines | German carmaker Porsche built several series of flat-eight engines of differing displacements over the course of many years. They were mainly used in Porsche's racing cars.
Type 753
The first Porsche flat-eight was the Type 753. Work began on it in 1960, following the announcement of a 1.5-litre displacement limit for the 1961 Formula One (F1) season. The design of the new F1 engine was done by Hans Hönick and Hans Mezger. The 753 inherited the traditional Porsche features of a boxer layout and air-cooling, but with the number of cylinders increased to eight.
Bore and stroke were respectively, resulting in a displacement of . The oversquare dimensions kept piston speeds low, and also kept the engine narrow and as far out of the airflow on the sides of the car's tub as possible, although it was still wider than the 120° V6 and 90° V8s of the competition.
The centre of the engine was a magnesium crankcase cast in two halves split vertically along the centre-line of the crankshaft. The crankcase carried a one-piece crankshaft in nine main bearings. The eight aluminum cylinder barrels had their bores treated with a spray-on molybdenum/steel coating called Ferral. Each finned cylinder had its own separate aluminum cylinder head, with four studs per cylinder holding the heads and barrels to the crankcase. An aluminum valve-gear cover cast as a single piece stabilized the four cylinders on each side of the engine.
The valvetrain was similar in some respects to that designed by Ernst Fuhrmann for the Type 547 four-cylinder engine. There were two overhead camshafts per cylinder bank, operating two valves per cylinder. As with the 547, the cams were driven by shafts rather than gears or chains, and the cam lobes were separate pieces that were keyed onto the shaft. The 753 added a second countershaft above the crankshaft to the single one underneath the crankshaft in the 547. Both countershafts rotated at half crankshaft speed. Two layshafts from the upper countershaft drove the left and right intake camshafts, while two other layshafts from the lower countershaft drove the exhaust camshafts, eliminating the vertical shafts in the 547's cylinder heads that gave that engine one of its nicknames. A short vertical shaft from the bevel gear on the right-hand inlet camshaft drove the axial cooling fan at 0.92x crankshaft speed. The valvetrain was designed to operate reliably at up to 10,000 rpm.
The engine had a dry sump system with a separate oil tank. A Bosch dual ignition system with four ignition coils and two distributors fired two spark plugs per cylinder. The air-fuel mixture was delivered by four Weber double downdraft carburetors; two on each side.
Assembly of the engine was a time-consuming job, often requiring repeated assembly and disassembly with extensive hand-fitting of components. Building and setting up a 753 never took less than 100 hours and could take up to 220 hours. The engine, with exhaust and clutch, was long, wide, high and weighed .
A prototype engine was first started on a test-bench on 12 December 1960. Initial power output was disappointing; (some sources say ), when the target had been .
Mezger and his team worked to improve both the engine's reliability and power output. The earliest engines had a 90° angle between the valves. When this was reduced, first to 84° and subsequently to 72°, power output rose. Other changes included reshaping the combustion chamber, lightening crank pins, and switching to titanium connecting rods. Power was eventually raised to .
Although the chassis of the Type 787 F1 car was lengthened to accommodate the 753, the flat-eight was never installed and the car used the 547 throughout its short life. The 753 engine debuted in Porsche's Formula One Type 804 on 20 May 1962 at the Dutch Grand Prix at Zandvoort. With a compression ratio of 10.0:1, the engine produced at 9200 rpm on its first outing. This was still less power than the new Coventry-Climax and BRM V8 engines. With the improved six-speed transmission from the Type 718 and a ZF limited-slip differential, the car reached a top speed of .
The 753 delivered Porsche's only F1 win as a constructor at the 1962 French Grand Prix at Rouen-Les-Essarts, in an 804 driven by Dan Gurney.
A short-stroke version of the engine was developed, designated the 753/1. The 753 also influenced the design of the engine for Porsche's 901 project, that would become the 911.
Type 771
A second version of the Porsche flat-eight meant for sports-racers in the 2 litre class was developed at the same time as the 753. This engine, designated Type 771, had a bore larger than the 753, resulting in an engine that displaced . Carburetor bores were increased to Power output rose to . This engine was used in the 718, 904 (of the 16 904s kept by the factory, six were fitted with the eight-cylinder engine), 906, 907, 909, and 910 sports-racer models between 1962 and 1968. A version of the 771 enlarged to was designated Type 771/1.
Type 908
The next flat-eight Porsche engine was not a further development of the Type 771, but rather a version of the Type 916 quad-cam six-cylinder racing engine with two additional cylinders. This engine first appeared in the Porsche 908 racers, and is called the Type 908 engine. The engine's internal dimensions were carried over from the Type 916, which had in turn inherited the measurements of the production 911 engine. Bore and stroke were respectively, for a total displacement of . With a 10.4:1 compression ratio, power output for the early versions was . The engine debuted at the Le Mans practice weekend on 6 April 1968.
Type 908 engines were installed in two VW-Porsche 914 cars at the factory in 1969. The first was built by Ferdinand Piëch using a full-blown racing engine developing . The second received a detuned version of the engine, and was given to Ferry Porsche as a gift on his 60th birthday. Called "914/8s", both are part of the collection at the Porsche Museum.
Type 1966
Another flat-eight engine design was related to Porsche internal project Type 1966, which corresponded to Volkswagen project EA266 of the late 1960s and early 1970s. The goal of EA266 was to develop a replacement for the Volkswagen Beetle. Volkswagen's prototypes used a rear mid-engine, rear-wheel-drive layout and were powered by a water cooled inline four cylinder engine with the cylinder bores laid over horizontally, mounted longitudinally under the rear passenger seat. Ferdinand Piëch envisioned the Type 1966 as the basis for a three-tiered replacement for the 911, with four-, eight-, and twelve-cylinder water cooled boxer engines mounted amidships. A design for a car with three-abreast seating was developed. A prototype flat-eight engine was also built for Piëch. The prototype engine was loosely based on the inline four developed for EA266, and included DOHC cylinder heads and two EA266 water cooled cylinder blocks on a common crankshaft. The new car was expected to be introduced in 1973. According to designer Anatole "Tony" Lapine, shortly after project EA266 was cancelled by Volkswagen all materials relating to the Type 1966 were destroyed, including the prototype engine.
Type 988/960
Rumours about another proposed Porsche flat-eight began to circulate in the mid-2010s. The mid-engined Porsche 988 (later renamed the 960) was to challenge the Ferrari 458 and Lamborghini Huracán models using a flat-eight engine that displaced 4 litres and was fitted with four turbochargers. Power output was projected to be in excess of . The 960 was expected to have been released in 2019, but some report that its release may have been pushed back as far as 2026.
References
Flat engines
Porsche in motorsport
Engines by model
Gasoline engines by model | Porsche flat-eight engines | [
"Technology"
] | 1,724 | [
"Engines",
"Engines by model"
] |
61,292,261 | https://en.wikipedia.org/wiki/Private%20set%20intersection | Private set intersection is a secure multiparty computation cryptographic technique that allows two parties holding sets to compare encrypted versions of these sets in order to compute the intersection. In this scenario, neither party reveals anything to the counterparty except for the elements in the intersection.
Other variants of this exist, such as the server-client scenario, in which only the client learns the intersection of her set with the set of the server, without the server learning intersection of his set with the clients.
For the comparison of data sets by cryptographic hashes on a small or predictable domain, precautions should be taken to prevent dictionary attacks.
Apple uses this technique in Password Monitoring. It has proposed using the technology for its announced Expanded Protections for Children
In general, PSI protocols can be categorized into two broad categories: (1) traditional PSI and (2) delegated PSI. In the traditional PSI category, the data owners interact directly with each other and need to have a copy of their set at the time of the computation, e.g.,. In the delegated PSI the computation of PSI and/or the storage of sets can be delegated to a third-party server (that is itself might be a passive or active adversary). The delegated PSI category can be further divided into two classes: (a) those that support one-off delegation, and (b) those that support repeated delegation. The PSI protocols that support one-off delegation require the data owner to re-encode its data and send the encoded data to the server for each computation, e.g.,. Those that support repeated delegation allow the data owners to upload their (encrypted) data to the server only once, and then re-use it many times for each computation carried out but the server, e.g.,
Recently, researchers have proposed a variant of PSI protocol (in both traditional and delegated categories) that support data update, e.g., . This type of PSI protocol lets data owners insert/delete set elements into/from their data with low overheads and in a privacy-preserving manner.
Educational example
This educational example demonstrated the key idea of PSI, but does not provide real-world cryptographic security (hence should not be used with real-world data).
# Example sets
party_a_set = {'apple', 'banana', 'cherry'}
party_b_set = {'banana', 'orange', 'apple'}
# Hashing the elements in both sets
hashed_party_a_set = {hash(e) for e in party_a_set}
hashed_party_b_set = {hash(e) for e in party_b_set}
# Finding the intersection of the hashed sets
intersection = hashed_party_a_set.intersection(hashed_party_b_set)
# Printing hashed intersection for demonstration
print(intersection)
References
Cryptography
Hashing | Private set intersection | [
"Mathematics",
"Engineering"
] | 609 | [
"Applied mathematics",
"Cryptography",
"Cybersecurity engineering"
] |
61,293,075 | https://en.wikipedia.org/wiki/List%20of%20galaxies%20with%20richest%20globular%20cluster%20systems | This is a list of galaxies with richest known globular cluster systems. As of 2019, the galaxy NGC 6166 has the richest globular cluster system, with 39 000 globular clusters. Other galaxies with rich globular cluster systems are NGC 4874, NGC 4889, NGC 3311 and Messier 87. For comparison, the Milky Way has a poor globular cluster system, with only 150-180 globular clusters.
References
Galaxies | List of galaxies with richest globular cluster systems | [
"Astronomy"
] | 98 | [
"Galaxies",
"Astronomical objects"
] |
61,294,445 | https://en.wikipedia.org/wiki/Dimethylolpropionic%20acid | Dimethylolpropionic acid (DMPA) is a chemical compound that has the full IUPAC name of 2,2-bis(hydroxymethyl)propionic acid and is an organic compound with one carboxyl and two hydroxy groups. It has the CAS Registry Number of 4767-03-7.
Properties
DMPA is an odorless free flowing white crystalline solid and essentially non-toxic. DMPA has two different functional groups hydroxyl and carboxylic acid so the molecule can be used for a wide variety of syntheses. In addition to reaction with other chemicals, DMPA can also react with itself to produce esters via esterification, as one example.
Uses
One key use of DMPA is in the field of coatings and adhesives. It is used as a modifier in the production of anionic Polyurethane dispersions. Solvent soluble binders/resins for coatings can be converted into an aqueous binder with the use of this material. In this case it is reacted with a suitable diisocyanate such as isophorone diisocyanate or TMXDI usually along with other polyols to make a prepolymer.
There is also the possibility of using 2,2-bis(hydroxymethyl)propionic acid for the synthesis of dendrimeric molecules, also known as hyperbranched molecules. When each hydroxyl group is reacted with 2,2-bis (hydroxymethyl) propionic acid, the number of hydroxyl groups present in the molecule doubles. Repeating this reaction step, produces one more shell each time and thus the molecule grows. If at the end the hydroxyl groups are reacted with a bifunctional component, dendrimeric UV binders can be produced, for example. Dendrimeric molecules have low solution viscosities and improved properties.
It has a wide variety of other uses including production of hyperbranched polyesters, waterborne polyesters, waterbased alkyd resins, and aqueous epoxy resins. It has even found use in polyethylene terephthalate fiber production. Another use is in the medical field for drug release purposes. In the business world it has been cited as an outstanding growth opportunity
See also
Prepolymer
Waterborne resins
References
External links
NIST
PubChem
Fabrichem website
Technical Data Sheet
Beta hydroxy acids
Coatings | Dimethylolpropionic acid | [
"Chemistry"
] | 524 | [
"Coatings"
] |
61,295,438 | https://en.wikipedia.org/wiki/Catovirus | Catovirus (CatV) is a genus of giant double-stranded DNA-containing viruses (nucleocytoplasmic large DNA viruses). This genus was detected during the analysis of metagenome samples of bottom sediments of reservoirs at the wastewater treatment plant in Klosterneuburg, Austria.
New Klosneuvirus (KNV), Hokovirus and Indivirus genera (all found in these sewage waters) were also described together with Catovirus, building up a putative virus subfamily Klosneuvirinae (Klosneuviruses) with KNV as type genus.
Catovirus has a large genome of 1.53 million base pairs (1176 gene families). This is the second largest genome among known Klosneuviruses after KNV (1.57 million base pairs, 1272 gene families). GC content is 26.4 %
Classification of metagenome, made by analyzing 18S rRNA indicate that their hosts are relate to the simple Cercozoa.
Phylogenetic tree topology of Mimiviridae is still under discussion. Some authors (CNS 2018) like to put Klosneuviruses together with Cafeteria roenbergensis virus (CroV) and Bodo saltans virus (BsV) into a tentative subfamily called Aquavirinae. Another proposal is to put these all together with Mimiviruses into a subfamily Megavirinae.
See also
Nucleocytoplasmic large DNA viruses
Girus
Mimiviridae
References
Further reading
Mitch Leslie: Giant viruses found in Austrian sewage fuel debate over potential fourth domain of life. In: Science. 5. April 2017, doi:10.1126/science.aal1005.
Virus genera
Mimiviridae
Unaccepted virus taxa | Catovirus | [
"Biology"
] | 364 | [
"Biological hypotheses",
"Unaccepted virus taxa",
"Controversial taxa"
] |
61,295,466 | https://en.wikipedia.org/wiki/Indivirus | Indivirus (IndV) is a genus of giant double-stranded DNA-containing viruses (NCLDV). This genus was detected during the analysis of metagenome samples of bottom sediments of reservoirs at the wastewater treatment plant in Klosterneuburg, Austria.
New Klosneuvirus (KNV), Hokovirus and Catovirus genera (all found in these sewage waters) were also described together with Indivirus, building up a putative virus subfamily Klosneuvirinae (Klosneuviruses) with KNV as type genus.
Indivirus has a genome of 0.86 million base pairs (660 gene families). This is the smallest genome among Klosneuviruses as mentioned above. GC content is 26.6 %
Classification of metagenome, made by analyzing 18S rRNA indicate that their hosts are relate to the simple Cercozoa.
Phylogenetic tree topology of Mimiviridae is still under discussion. Some authors (CNS 2018) like to put Klosneuviruses together with Cafeteria roenbergensis virus (CroV) and Bodo saltans virus (BsV) into a tentative subfamily called Aquavirinae. Another proposal is to put them all together with Mimiviruses into a subfamily Megavirinae.
See also
Nucleocytoplasmic large DNA viruses
Girus
Mimiviridae
References
Further reading
Mitch Leslie: Giant viruses found in Austrian sewage fuel debate over potential fourth domain of life. In: Science. 5. April 2017, doi:10.1126/science.aal1005.
Virus genera
Mimiviridae
Unaccepted virus taxa | Indivirus | [
"Biology"
] | 340 | [
"Biological hypotheses",
"Unaccepted virus taxa",
"Controversial taxa"
] |
61,295,777 | https://en.wikipedia.org/wiki/CooA | CooA is a heme-containing transcription factor that responds to the presence of carbon monoxide. This protein forms homodimers and is a homolog of cAMP receptor protein. CooA regulates the expression of carbon monoxide dehydrogenase, an enzyme that catalyzes the oxidation of CO to CO2. The most well-studied CooA homolog comes from Rhodospirillum rubrum (RrCooA), but the CooA homolog from Carboxydothermus hydrogenoformans (ChCooA) has been studied as well. The main difference between these two CooA homologs is the ferric heme coordination. For RrCooA, the ferric heme iron is bound to a cysteine and the amine of the N-terminal proline, while, in the ferrous state, a ligand switch occurs where a nearby histidine displaces the thiolate. For ChCooA, the heme iron is ligated by a histidine and the N-terminal amine in both the ferric and ferrous states. For both homologs, CO displaces the amine ligand and activates the protein to bind to its target DNA sequence. Several structures of CooA exist: RrCooA in the ferrous state (1FT9), ChCooA in the ferrous, imidazole-bound state (2FMY), and ChCooA in the ferrous, CO-bound state (2HKX).
References
Gene expression
Protein families
DNA
Gaseous signaling molecules | CooA | [
"Chemistry",
"Biology"
] | 337 | [
"Gene expression",
"Protein classification",
"Signal transduction",
"Gaseous signaling molecules",
"Molecular genetics",
"Induced stem cells",
"Cellular processes",
"Molecular biology",
"Biochemistry",
"Protein families",
"Transcription factors"
] |
61,296,688 | https://en.wikipedia.org/wiki/Lightricks | Lightricks, founded in January 2013, is a company that develops video and image editing mobile apps and software, known particularly for its selfie-editing app, Facetune.
Headquartered in Jerusalem, the firm has approximately 600 employees. As of 2023, its apps have been downloaded over 730 million times. In 2024, Lightricks introduced LTX Studio, a platform for creating and editing videos using AI.
History
The company was created in 2013 by 5 founders, Ph.D. students Zeev Farbman, Nir Pochter, Yaron Inger, Amit Goldstein, and former Supreme Court of Israel clerk Itai Tsiddon who were all studying at the Hebrew University of Jerusalem. Lightricks began life as a bootstrapped company, which was the subject of a case study from the Harvard Business School "Bootstrapping at Lightricks".
The company received in 2015 its first funding round of $10 million led by Viola Ventures. It received its second round of funding of $60 million in November 2018, led by Insight Venture Partners and with participation from Israeli VC company ClalTech. In July 2019, it secured $135 million in series C funding led by Goldman Sachs, with participation from Insight Partners and ClalTech; this was reported to imply a $1 billion valuation. It puts the total raised to date at $205 million.
Lightricks ended 2018 with over $50 million in revenue.
In September 2021, the company received $100 million in primary and $30 million in secondary Series D funding. This valued the company at $1.8 billion.
Operations
After beginning in the Hebrew University campus, the company outgrew its space a number of times. It remains based in Jerusalem, Israel, with offices in Haifa, London and Chicago; it has a total of approximately 600 employees.
Once Apple Inc allowed it, Lightricks was one of the first app companies to offer subscriptions. Most of its apps are now published under a freemium model.
Products
Flagship Products
Facetune, a world renowned selfie editing app, which was named as Apple's most downloaded app in 2017. In 2021 it was ranked as one of Apple's top-5 paid apps for the seventh consecutive year.
Photoleap (formerly known as Photofox and Enlight), a general image editing app, which was preceded by Enlight Photofox. The app allows the user to generate artwork to be shared on social media with a number of different editing options. It was one of the first mobile applications to offer generative AI capabilities and text-to-image.
Videoleap, a video editor.
Popular Pays, an influencer marketing and content creation platform, acquired in 2022.
LTX Studio, an AI powered platform for video generation, pre-production storyboarding and post-production edits.
Other Apps
Lightleap (formerly known as Quickshot), a pre-image viewer.
Motionleap (formerly known as Pixaloop), an image animation tool created in 2018 where one can animate otherwise-still elements of a picture in different ways.
Beatleap, an audio-first video editing tool. The app features music by Epidemic Sound.
Artleap (formerly known as QuickArt), a photo editing tool.
Seen, a story making tool.
Boosted (formerly known as BoostApps), a graphic design template tool aimed towards social media marketing.
Facetune Video, a selfie-retouching video tool that allows users to retouch and edit their selfie and portrait videos in real time using a set of A.I.-powered tools. Integrated into Facetune.
Filtertune, a photo filter tool designed to create a community around custom photo filters. With the app, creators can make their own personalized preset photo filters, then share them across social media as photos with a QR code attached.
References
External links
IOS software
Photo software
Companies based in Jerusalem
Mobile software
Software companies of Israel
Software companies established in 2013
2013 establishments in Israel | Lightricks | [
"Technology",
"Engineering"
] | 826 | [
"Software engineering",
"Computer science",
"Software",
"nan"
] |
62,552,105 | https://en.wikipedia.org/wiki/Turing%20Tumble | Turing Tumble is a game and demonstration of logic gates via mechanical computing.
Description
Named after Alan Turing, the game could, in the abstract, duplicate the processes of any computer whatsoever if the game field itself were sufficiently large. This follows because the game is P-complete by the circuit value problem and PSPACE-complete if an exponential number of marbles is allowed. The device has implications for nanotechnology.
The game is advertised as Turing complete: an extension of the game that allows an infinitely large board and infinitely many pieces has been shown to be Turing complete via simulations of both Rule 110 for cellular automata, as well as of Turing machines.
Although it resembles a pachinko machine in its aesthetic use of gravity-fed metal balls, it is primarily a teaching device in the fundamentals of logic-computer programming, and as such is an example of gamification. The framing device in the included comic book features an astronaut who must solve 60 increasingly difficult logic problems which illustrate the fundamentals of computer programming.
History
The impetus of the puzzles included with the device was the frustration of the programmer and chemistry professor Paul Boswell (along with his wife, Alyssa Boswell, a DIY maker), then at the University of Minnesota, at the lack of computing prowess of other scientists which was necessary for their own projects. Boswell was already well known for programming complex games for Texas Instruments computers. The inventors were also inspired by the Digi-Comp II, a precursor from the late 1960s.
Components
A Turing Tumble machine has the following parts:
Ball drops – The standard version uses two ramps which store a given number of balls. A switch at the bottom of the board triggers the release of the initial ball (typically blue), from the top left of the panel. The second ramp, on the right, contains red balls.
Ramps and crossovers – The green ramp allows the balls to run down it one way and release it in only that direction, whereas the orange crossover lets balls traverse it to either side both ways, i.e. from right to left and vice versa.
Interceptors – This black piece stops a ball.
Bits – This is a one-bit storage: it changes direction when a ball rolls through, such that the next ball goes to the other side.
Gear and gear bits – Gear bits are exactly like regular bits, but they can be connected to gears. The gears allow for linking state changes, thus integrally adding extra (abstract) power.
Reception
Critically, the device has received high praise for its concept and execution, albeit with some caveats (the recommended age being 8+).
The computing game has won the Parents' Choice Gold Award, and won in the category "Best Toys of the Year 2018" under the aegis of the American Specialty Toy Retailing Association.
References
External links
Turing tumble simulator (JavaScript)
Mechanical computers
Educational toys
Computer-related introductions in 2017 | Turing Tumble | [
"Physics",
"Technology"
] | 589 | [
"Physical systems",
"Machines",
"Mechanical computers"
] |
62,552,694 | https://en.wikipedia.org/wiki/Yorgo%20Modis | Yorgo E. Modis (born 1974) is Professor in Virology and Immunology, and a Wellcome Trust Senior Research Fellow at the Department of Medicine, University of Cambridge. He is head of The Modis Lab in the Molecular Immunity Unit at the MRC Laboratory of Molecular Biology. He studies cellular mechanisms of viral gene sensing and silencing. His group employs a diverse set of complementary biophysical approaches including cryo-electron microscopy (cryoEM), X-ray crystallography, solution biophysics, fluorescence microscopy and cell biological approaches to understand the cellular mechanisms of viral gene sensing and silencing in molecular-level detail.
Education and early life
Modis received his International Baccalaureate from the International School of Geneva, Switzerland. He then studied Biochemistry at the University of Cambridge. He did his graduate work in Structural Biology with Rik A. Wierenga at the European Molecular Biology Laboratory Heidelberg obtaining his Ph.D. from the University of Leeds in 1999. For the next six years he worked as a Postdoctoral Fellow with Stephen C. Harrison at Harvard Medical School, Boston, U.S.A.
Research and professional experience
While at Harvard (1999–2005) Modis co-authored five publications that featured on the cover of international scientific journals. Among them was the subject of viral entry into host cells by the dengue virus, which became a cover story on Nature (journal). The work gave rise to an award-winning animation Dengue Viral Fusion.
At Yale Modis was first Assistant Professor (2005–2010) and then Associate Professor (2010–2014) of Molecular Biophysics & Biochemistry. In those capacities he carried out research that led to numerous publications on which he was corresponding author and/or principal investigator.
In 2014 Modis accepted a position as Wellcome Trust Senior Research Fellow at University of Cambridge. He became the head of research group The Modis Lab at MRC Laboratory of Molecular Biology. Two years later he was named University Reader in Virology and Immunology. In 2021 he was named Professor in Virology and Immunology.
In these capacities Modis has co-authored a number of publications as principal investigator.
A full list of his publications (around 70) can be found here.
He has also been invited to, organized, or served as keynote speaker in over 100 seminars and conferences.
In May 2020 he helped Roger Highfield to set up a blog at the Science Museum Group with the theme Coronavirus: How the Virus Works.
In July 2020 he contributed graphics of the COVID-19 virus to the BBC News article by John Sudworth with title Wuhan: City of silence — Looking for answers in the place where coronavirus started.
Honors and awards
2019 Senior Research Fellowship from the Wellcome Trust
2014 Senior Research Fellowship from the Wellcome Trust
2009 CINE Golden Eagle Award for the animation “Dengue Virus Visualization” on Teachers’ Domain
2008 Nominated for the 2009 American Crystallography Association Margaret C. Etter Early Career Award (the award went to Dr. Svilen Bobev)
2007 Investigator in the Pathogenesis of Infectious Disease, Burroughs Wellcome Fund
2007 Anderson Endowed Bridge Fellowship Award, Yale University
2006 Anderson Endowed Fellowship Award, Yale University
2000-2004 Human Frontier Science Program Organization Long-Term Postdoctoral Fellowship
1999-2000 European Molecular Biology Organization Long-Term Fellowship
1999 Roche Foundation Postdoctoral Fellowship (declined)
1999 Swiss National Science Foundation Fellowship (declined)
1995-1999 Predoctoral Fellowship, European Molecular Biology Laboratory (4 years)
1995 Bateman Scholarship- First Class Honors Degree, Trinity Hall, University of Cambridge, U.K.
1995 Kareen Thorne Prize- Top First Class Honors Degree in Biological Sciences, Trinity Hall, University of Cambridge, U.K.
1995 First Class Honours (top grade) Bachelor of Arts degree in biochemistry, University of Cambridge, U.K.
1992 Top grade (7) in all six subjects of the International Baccalaureate at the International School of Geneva, Switzerland
Personal life
Modis is the son of Theodore Modis and Carole Gene Modis. He is the great-grandson of Theodoros Modis and grandnephew of Georgios Modis.
References
1974 births
Living people
Swiss biologists
Swiss people of Greek descent
Molecular biologists | Yorgo Modis | [
"Chemistry"
] | 863 | [
"Biochemists",
"Molecular biology",
"Molecular biologists"
] |
62,553,423 | https://en.wikipedia.org/wiki/Charles%20Rezk | Charles Waldo Rezk (born 26 January 1969) is an American mathematician, specializing in algebraic topology and category theory.
Education and career
Rezk matriculated at the University of Pennsylvania in 1987 and graduated there in 1991 with B.A. and M.A. in mathematics. In 1996 he received his PhD from MIT with thesis Spaces of Algebra Structures and Cohomology of Operads and advisor Michael J. Hopkins. At Northwestern University Rezk was a faculty member from 1996 to 2001. At the University of Illinois he was an assistant professor from 2001 to 2006 and an associate professor from 2006 to 2014, and has been a full professor since 2014.
He was at the Institute for Advanced Study in the fall of 1999, the spring of 2000, and the spring of 2001. He held visiting positions at MIT in 2006 and at Berkeley's MSRI in 2014. Since 2015 he has been a member of the editorial board of Compositio Mathematica.
Rezk was an invited speaker at the International Congress of Mathematicians in Seoul in 2014. He was elected a Fellow of the American Mathematical Society in the class of 2015 (announced in late 2014).
Selected publications
References
External links
1969 births
Living people
20th-century American mathematicians
21st-century American mathematicians
University of Pennsylvania alumni
Massachusetts Institute of Technology School of Science alumni
Northwestern University alumni
University of Illinois Urbana-Champaign faculty
Fellows of the American Mathematical Society
American topologists
Category theorists | Charles Rezk | [
"Mathematics"
] | 290 | [
"Category theorists",
"Mathematical structures",
"Category theory"
] |
62,554,271 | https://en.wikipedia.org/wiki/NGC%207812 | NGC 7812 (also known PGC 195) as is an intermediate spiral galaxy in the constellation Sculptor. The galaxy was discovered on 25 September 1865 by Sir John Hershel. At its widest, it measures approximately 100-thousand light years (30660 parsecs) across, and is 315 million light years away from Earth.
See also
List of NGC objects (7001–7840)
References
External links
Astronomical objects discovered in 1865
Discoveries by John Herschel
7812
Intermediate spiral galaxies
Sculptor (constellation) | NGC 7812 | [
"Astronomy"
] | 104 | [
"Constellations",
"Sculptor (constellation)"
] |
62,554,597 | https://en.wikipedia.org/wiki/Phoma%20wilt | Phoma wilt is a disease of the common hop plant caused by several species of fungal plant pathogens in the genus Phoma. These include Phoma herbarum and Phoma exigua, and possibly other as yet unidentified species. Phoma infection may cause decreased yields, but Phoma wilt is not considered to be a very common or destructive disease of the hop plant.
Hosts and symptoms
Phoma herbarum and P. exigua have both been found to have wide host specificity, although the hop plant appears to be the only common host of the two. There have not been any indications found of cultivar specificity, although hop yards established for a longer time may have a higher risk of Phoma infection . Symptoms of infection typically begin with small chlorotic leaf spots and develop into greyish brown lesions that have a distinct target or concentric ring appearance. In some instances, the lesions may also be greyish white in color. Infection of the hop cones will produce brown or red discoloration covering some or all of the bracts of the hop cone. This discoloration is an indication of necrosis on the cones. The plant may also develop cankers or wilt, but this is not seen in all cases. Phoma wilt of hops may be diagnosed by its characteristic symptoms or by isolation and DNA sequencing of the pathogen against known genomes.
Interestingly, P. herbarum and P. exigua have also both been considered as bioherbicide agents against some species of broadleaf weeds.
Disease cycle
Phoma wilt in hops has been found to be spread by pycnidiospores. These asexual spores are released from mature pycnidia in a matrix which may appear white or pink. Dissemination occurs largely by rain splash, wind, or misting, but spores may also be carried by bird or insect vectors from plant to plant. Infection, which typically becomes evident in late Summer, may occur by spores entering through stomata or wounds in the plant but may also enter directly through the epidermis. Spores will then bud and divide, and hyphae will branch out. The initial infection is symptom-less as the pathogen spreads. However, once the pathogen becomes necrotrophic, necrotic lesions will appear. Pycnidia formation begins with hyphae near the epidermis in lesions forming a cavity followed by the production of dark hyphal cells. The aggregation will continue to grow in size until it is mature. Spore production starts from the inner cells of the pycnidia, and stalks of spores project inward in columns from those cells. Spores are oblong and generally measure approximately 5.0 x 2.5 μm. There is no sexual stage for either P. herbarum or P. exigua that has been identified, but many other species of Phoma have been found with a Didymalla teleomorph.
In the absence of a host, P. herbarum and P. exigua can act saprophytically survive in plant debris or decaying material.
Environment
Phoma wilt of hops generally requires rain for dissemination by rain splash, but there is some evidence that it may thrive from periods of dryness with interspersed, shorter periods of wetness. Repeatedly growing hops in the same area where Phoma wilt occurred previously increases disease incidence rate, as the pathogen is able to survive in debris and material on the ground. There is also evidence that birds and insects which frequent the hop plant may act as transient vectors of the disease.
Management
There are currently no specific management techniques described for Phoma Wilt in Hops. However, several methods have been proposed. The simplest cultural method is the removal of plant debris from hop yards which may help reduce the spread of the disease as well as initial infection in new stock. This functions by effectively removing any resting spores, pycnidia, or saprophytic pathogen. Any diseased plants or plant material should also be removed. Because the disease prefers moist condition for dissemination, it may also be helpful to ensure hop plants have adequate airflow. This likely, not an issue though due to the way hop vines are guided upward on wires. It is also important to water the hop plants from the ground as opposed to misting or sprinkler type systems which will create or prolong a moist environment where the pathogen can thrive. Because the pathogen is also able to survive in the soil, growing a non-host plant in the area for 4+ years could be used to halt future infection; however, the longevity of the hop plant rhizome may reduce the efficiency of this cultural practice. Sterile practice should also be used when pruning, transporting, or propagating stock to impede the spread of the pathogen. There are fungicides available that have an action against the Phoma species seen in hops, but none specifically registered for Phoma wilt in hops, though chemical treatments have been proposed for the treatment of the disease. These include tebuconazole, trifloxystrobin, fosetyl-Al, and copper hydroxide for their action against fungi in general. Tebuconazole is a systemic fungicide which interferes with membrane functions and pathogen survival within the hop plant. The fungicide trifloxystrobin acts by interfering with some aspects of fungal pathogen respiration, resulting in the inhibition of both growth and spore germination. This functionally stops the initial infection or subsequent growth. Fosetyl-Al has a less distinct mode of action, likely having fungicidal properties by stimulating defense mechanisms in the host plant itself . Fosetyl-Al may therefore help decrease the spread of the Phoma infection in hop plant tissues, but this has yet to be studied more closely. Copper hydroxide is a widely used foliar applied fungicide which denatures proteins on the plant surface and inhibits pathogen forced entry. This may not be completely effective against Phoma, as it is also able to enter through wounds and natural openings.
References
Hop diseases
Fungal plant pathogens and diseases
Fungal diseases | Phoma wilt | [
"Biology"
] | 1,267 | [
"Fungi",
"Fungal diseases"
] |
62,555,023 | https://en.wikipedia.org/wiki/Erysiphe%20syringae | Powdery mildew of lilac, or Erysiphe syringae (formerly Microsphaera syringae) is a fungal pathogen of lilacs.
Importance
The host of the fungal pathogen, Syringa vulgaris or the common lilac, is an ancient plant with significance in horticultural activities and wild roots in eastern Europe. Its Latin epithet, vulgaris, translates into ‘common’ in English, and was popularized by the pioneer taxonomist Carl von Linné.
One of the first dutiful observations of the pathogen, E. syringae, was made in a journal of the German Botanical Society, Berichte der Deutschen Botanische Gesellschaft, where it was observed as a powdery mildew pathogen unique to lilacs referencing the physical characteristics of its ascocarp appendages.
The pathogen contributes to a deathly and diseased look. Common lilac is known for its spring flowers, which can be altered due to decay of flowering stems after intense infection.
Symptoms
Powdery mildew of lilac leaves an opaque-white discoloration on the leaves of S. vulgaris. This process is predominant at the end of the season but can begin to take place during new growth. Eventually the fungal pathogen contributes to the damaging and early senescing of the infected leaves. The opaque-white discoloration is mycelial growth along the surface of the leaf. When the pathogen is sufficiently advanced, the presence of small dark dots indicates the production of cleistothecium (chasmothecium), an important structure in the protection of potential inoculum.
Treatment
There are methods to treat powdery mildew using home-made preparations including fresh milk, which contains the active anti-pathogenic compound lecithin. Lecithin is recognized by the European Union as a treatment for powdery mildews diseases and is commonly available in the soy-derived formulation ‘soy lecithin’. Other experimental treatments include using baking soda (disrupts pH), neem oil (fungicidal properties), or sulfur containing solutions. Historically, flowers of sulfur has been prepared into a dust and applied to the leaves.
Synthetic compounds such as thiophanate-methyl, propiconazole and chlorothalonil are used to treat variety of powdery mildew diseases, as well as other fungal pathogens.
Many chemical treatments are known to contribute to disease resistance, and can be harmful if not used with appropriate caution. Compounds with high risk such as thiophanate-methyl can be referred to in the FRAC (Fungicide Resistance Action Committee) Code List document. To avoid health risks refer to the product's label and the appropriate Material Safety Data Sheet.
Cultural controls such as selective pruning can prevent suitable environmental conditions of the pathogen by increasing air circulation. Collection and destruction of plant debris can disrupt the pathogen’s life cycle.
References
syringae
Fungal plant pathogens and diseases
Fungus species | Erysiphe syringae | [
"Biology"
] | 605 | [
"Fungi",
"Fungus species"
] |
62,555,539 | https://en.wikipedia.org/wiki/KLJN%20Secure%20Key%20Exchange | Random-resistor-random-temperature Kirchhoff-law-Johnson-noise key exchange, also known as RRRT-KLJN or simply KLJN, is an approach for distributing cryptographic keys between two parties that claims to offer unconditional security. This claim, which has been contested, is significant, as the only other key exchange approach claiming to offer unconditional security is Quantum key distribution.
The KLJN secure key exchange scheme was proposed in 2005 by Laszlo Kish and Granqvist. It has the advantage over quantum key distribution in that it can be performed over a metallic wire with just four resistors, two noise generators, and four voltage measuring devices---equipment that is low-priced and can be readily manufactured. It has the disadvantage that several attacks against KLJN have been identified which must be defended against.
"Given that the amount of effort and funding that goes into Quantum Cryptography is substantial (some even mock it as a distraction from the ultimate prize which is quantum computing), it seems to me that the fact that classic thermodynamic resources allow for similar inherent security should give one pause," wrote Henning Dekant, the founder of the Quantum Computing Meetup, in April 2013.
The Cybersecurity Curricula 2017, a joint project of the Association for Computing Machinery, the IEEE Computer Society, the Association for Information Systems, and the International Federation for Information Processing Technical Committee on Information Security Education (IFIP WG 11.8) recommends teaching the KLJN Scheme as part of teaching "Advanced concepts" in its knowledge unit on cryptography.
See Also/Further Reading
http://www.scholarpedia.org/article/Secure_communications_using_the_KLJN_scheme
http://noise.ece.tamu.edu/research_files/research_secure.htm
Science: Simple Noise May Stymie Spies without Quantum Weirdness, Adrian Cho, September 30, 2005. http://noise.ece.tamu.edu/news_files/science_secure.pdf
References
Cryptography | KLJN Secure Key Exchange | [
"Mathematics",
"Engineering"
] | 438 | [
"Applied mathematics",
"Cryptography",
"Cybersecurity engineering"
] |
62,555,964 | https://en.wikipedia.org/wiki/Botrytis%20elliptica | Botrytis elliptica is a necrotrophic fungal pathogen which infects species of plants in the Lilium genus, causing the disease commonly known as Lily Gray Mold. The symptoms of Lily Gray Mold include the appearance of water-soaked spots on leaves which appear white and increase in darkness with age, ranging from gray to brown. These spots may cover the entire leaf, complemented with a gray webbing, containing the fungal spores. The leaves will appear wilted and branches may die back. In addition to leaves, petals, stems, and buds may be infected, and this gray webbing will eventually cover the plant, feigning the appearance of gray flowers. Infected buds often rot. Lily Gray Mold disease, if not properly treated, will appear each year with increasing vigor.
Disease cycle
The disease cycle for Botrytis elliptica begins with infection of plants in spring. This may be derived from mycelium in overwintering sclerotia, which produce conidiophores to create conidia, the asexual spores of this fungus. The conidia germinate, often penetrating the young leaf tissue of the lily, although the flowers, buds, or stem may also suffer from infection. This infects cells, which collapse, disintegrate, and rot the tissue. This cycle is polycyclic. The conidiophores spread, producing more conidia to further infect new areas of the plant or spread to new plants.
Additionally, B. elliptica reproduces sexually via a heterothallic mating system with two alleles: MAT1-1 and MAT1-2. All ascomycetes studied of B. elliptica contain these genes, which are orthologous to the alpha-domain protein (MAT1-1) and the HMG-domain protein (MAT1-2). These proteins act together as a master regulator the initiation of sexual fruiting body development, which begins when both proteins are expressed in a dikaryotic cell. Apothecia result from this union. These are brown in color, and darken as they mature, and they range between 7–12 mm in height, with apothecial disks from 3–4 mm diameter and 0.5-1.0 mm in thickness. The ascospores produced from the apothecia are 23 x 10 μm. These ascospores infect Lilium species’ leaves as effectively as the conidia throughout the growing season, although mycelium are the primary inoculants of young lily shoots in the spring. These ascospores may overwinter in the dead leaf debris and infect new foliage in the spring.
Management
As Lilium species are of great horticultural interest in ornamental production, B. elliptica must be prevented and managed to continue production. Plant breeders currently work to determine Botrytis-resistant cultivars of Lilium. The rapid accumulation of hydrogen peroxide, nitrous oxide, and antioxidant activity trigger in the plant's defense response, and long-term, highly concentrated increases contribute to high resistance in these plants. Cultivars displaying high resistance are the Oriental and Oriental x Trumpet hybrid lines, whereas the susceptible cultivars included Asiatic and Trumpet cultivars. Defense responses found in Lilium species are mediated by phytohormones involved in jasmonate signaling, increasing the transcription for defense-related proteins. These proteins include receptor kinases, antioxidant enzymes, polyphenol oxidase, pathogenesis-related proteins, and proteins involved in the phenylpropanoid metabolism. Highly resistant Lilium species cultivars express genes producing these proteins more effectively than in the susceptible cultivars.
In addition to breeding for Botrytis-resistant cultivars, steps can be taken to prevent the spread of this mold in the field. Because this mold requires water to spread to other plants, Botrytis can be greatly reduced with good drainage to the soil and caution to avoid overwatering. Additionally, sanitation of plants is extremely important, such as deadheading dying flowers and removing infected leaves. The ascospores on this debris could overwinter and infect the plants in the spring, so it is advised to either bury the debris in a hole at least 12” deep or, preferably, burn it. Fungicides are rarely needed and are typically used as a prevention method early in the season. Thiophanate-methyl, copper fungicides or, as a weak fungicide, neem oil, can be effectively used in home gardens, although with caution, particularly with new cultivars of Lilium species. These treatments should be applied to selected plants before treating an entire bed, and always using the recommended instructions on the product's label.
References
Sclerotiniaceae
Fungal plant pathogens and diseases
Taxa named by Miles Joseph Berkeley
Fungi described in 1881
Fungus species | Botrytis elliptica | [
"Biology"
] | 1,014 | [
"Fungi",
"Fungus species"
] |
62,556,833 | https://en.wikipedia.org/wiki/Impulse%20vector | An impulse vector, also known as Kang vector, is a mathematical tool used to graphically design and analyze input shapers that can suppress residual vibration. The impulse vector can be applied to both undamped and underdamped systems, as well as to both positive and negative impulses in a unified manner. The impulse vector makes it easy to obtain impulse time and magnitude of the input shaper graphically.
A vector concept for an input shaper was first introduced by W. Singhose for undamped systems with positive impulses. Building on this idea, C.-G. Kang introduced the impulse vector (or Kang vector) to generalize Singhose's idea to undamped and underdamped systems with positive and negative impulses.
Definition
For a vibratory second-order system with undamped natural frequency and damping ratio , the magnitude and angle of an impulse vector (or Kang vector) corresponding to an impulse function , is defined in a 2-dimensional polar coordinate system as
where implies the magnitude of an impulse function, implies the time location of the impulse function, and implies damped natural frequency . For a positive impulse function with , the initial point of the impulse vector is located at the origin of the polar coordinate system, while for a negative impulse function with , the terminal point of the impulse vector is located at the origin. □
In this definition, the magnitude is the product of and a scaling factor for damping during time interval , which represents the magnitude before being damped; the angle is the product of the impulse time and damped natural frequency. represents the Dirac delta function with impulse time at .
Note that an impulse function is a purely mathematical quantity, while the impulse vector includes a physical quantity (that is, and of a second-order system) as well as a mathematical impulse function. Representing more than two impulse vectors in the same polar coordinate system makes an impulse vector diagram. The impulse vector diagram is a graphical representation of an impulse sequence.
Consider two impulse vectors and in the figure on the right-hand side, in which is an impulse vector with magnitude and angle corresponding to a positive impulse with , and is an impulse vector with magnitude and angle corresponding to a negative impulse with . Since the two time-responses corresponding to and are exactly same after the final impulse time as shown in the figure, the two impulse vectors and can be regarded as the same vector for vector addition and subtraction. Impulse vectors satisfy the commutative and associative laws, as well as the distributive law for scalar multiplication.
The magnitude of the impulse vector determines the magnitude of the impulse, and the angle of the impulse vector determines the time location of the impulse. One rotation, angle, on an impulse vector diagram corresponds to one (damped) period of the corresponding impulse response.
If it is an undamped system (), the magnitude and angle of the impulse vector become and .
Properties
Property 1: Resultant of two impulse vectors.
The impulse response of a second-order system corresponding to the resultant of two impulse vectors is same as the time response of the system with a two-impulse input corresponding to two impulse vectors after the final impulse time regardless of whether the system is undamped or underdamped. □
Property 2: Zero resultant of impulse vectors.
If the resultant of impulse vectors is zero, the time response of a second-order system for the input of the impulse sequence corresponding to the impulse vectors becomes zero also after the final impulse time regardless of whether the system is undamped or underdamped. □
Consider an underdamped second-order system with the transfer function . This system has and . For given impulse vectors and as shown in the figure, the resultant can be represented in two ways, and , in which corresponds to a negative impulse with and , and corresponds to a positive impulse with and .
The resultants , can be found as follows.
,
Note that . The impulse responses and corresponding to and are exactly same with after each impulse time location as shown in green lines of the figure (b).
Now, place an impulse vector on the impulse vector diagram to cancel the resultant as shown in the figure. The impulse vector is given by
.
When the impulse sequence corresponding to three impulse vectors and is applied to a second-order system as an input, the resulting time response causes no residual vibration after the final impulse time as shown in the red line of the bottom figure (b). Of course, another canceling vector can exist, which is the impulse vector with the same magnitude as but with an opposite arrow direction. However, this canceling vector has a longer impulse time that can be as much as a half period compared to .
Applications: Design of input shapers using impulse vectors
ZVDn shaper
Using impulse vectors, we can redesign known input shapers such as zero vibration (ZV), zero vibration and derivative (ZVD), and ZVDn shapers.
The ZV shaper is composed of two impulse vectors, in which the first impulse vector is located at 0°, and the second impulse vector with the same magnitude is located at 180° for . Then from the impulse vector diagram of the ZV shaper on the right-hand side,
.
Therefore, .
Since (normalization constraint) must be hold, and ,
.
Therefoere, .
Thus, the ZV shaper is given by
.
The ZVD shaper is composed of three impulse vectors, in which the first impulse vector is located at 0 rad, the second vector at rad, and the third vector at rad, and the magnitude ratio is . Then . From the impulse vector diagram,
.
Therefore, .
Also from the impulse vector diagram,
.
Since must be hold,
.
Therefore, .
Thus, the ZVD shaper is given by
.
The ZVD2 shaper is composed of four impulse vectors, in which the first impulse vector is located at 0 rad, the second vector at rad, the third vector at rad, and the fourth vector at rad, and the magnitude ratio is . Then . From the impulse vector diagram,
.
Therefore, .
Also, from the impulse vector diagram,
.
Since must be hold,
.
Therefore, .
Thus, the ZVD2 shaper is given by
.
Similarly, the ZVD3 shaper with five impulse vectors can be obtained, in which the first vector is located at 0 rad, the second vector at rad, third vector at rad, the fourth vector at rad, and the fifth vector at rad, and the magnitude ratio is . In general, for the ZVDn shaper, i-th impulse vector is located at rad, and the magnitude ratio is where implies a mathematical combination.
ETM shaper
Now, consider equal shaping-time and magnitudes (ETM) shapers, with the same magnitude of impulse vectors and with the same angle between impulse vectors. The ETMn shaper satisfies the conditions
.
Thus, the resultant of the impulse vectors of the ETMn shaper becomes always zero for all . One merit of the ETMn shaper is that, unlike the ZVDn or extra insensitive (EI) shapers, the shaping time is always one (damped) period of the time response even if n increases.
The ETM4 shaper with four impulse vectors is obtained from the above conditions together with impulse vector definitions as
.
.
The ETM5 shaper with five impulse vectors is obtained similarly as
.
.
In the same way, the ETMn shaper with can be obtained easily. In general, ETM shapers are less sensitive to modeling errors than ZVDn shapers in a large positive error range. Note that the ZVD shaper is an ETM3 shaper with .
NMe shaper
Moreover, impulse vectors can be applied to design input shapers with negative impulses. Consider a negative equal-magnitude (NMe) shaper, in which the magnitudes of three impulse vectors are , and the angles are . Then the resultant of three impulse vectors becomes zero, and thus the residual vibration is suppressed. Impulse time of the NMe shaper are obtained as , and impulse magnitudes are obtained easily by solving the simultaneous equations
.
The resulting NMe shaper is
.
.
The NMe shaper has faster rise time than the ZVD shaper, but it is more sensitive to modeling error than the ZVD shaper. Note that the NMe shaper is the same with the UM shaper if the system is undamped ().
Figure (a) in the right side shows a typical block diagram of an input-shaping control system, and figure (b) shows residual vibration suppressions in unit-step responses by ZV, ZVD, ETM4 and NMe shapers.
Refer to the reference for sensitivity curves of the above input shapers, which represent the robustness to modeling errors in and .
References
Dynamics (mechanics)
Control theory
Mechanical vibrations | Impulse vector | [
"Physics",
"Mathematics",
"Engineering"
] | 1,830 | [
"Structural engineering",
"Physical phenomena",
"Applied mathematics",
"Control theory",
"Classical mechanics",
"Motion (physics)",
"Dynamics (mechanics)",
"Mechanics",
"Mechanical vibrations",
"Dynamical systems"
] |
62,557,527 | https://en.wikipedia.org/wiki/Fresh%20water | Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. The term excludes seawater and brackish water, but it does include non-salty mineral-rich waters, such as chalybeate springs. Fresh water may encompass frozen and meltwater in ice sheets, ice caps, glaciers, snowfields and icebergs, natural precipitations such as rainfall, snowfall, hail/sleet and graupel, and surface runoffs that form inland bodies of water such as wetlands, ponds, lakes, rivers, streams, as well as groundwater contained in aquifers, subterranean rivers and lakes.
Water is critical to the survival of all living organisms. Many organisms can thrive on salt water, but the great majority of vascular plants and most insects, amphibians, reptiles, mammals and birds need fresh water to survive.
Fresh water is the water resource that is of the most and immediate use to humans. Fresh water is not always potable water, that is, water safe to drink by humans. Much of the earth's fresh water (on the surface and groundwater) is to a substantial degree unsuitable for human consumption without treatment. Fresh water can easily become polluted by human activities or due to naturally occurring processes, such as erosion.
Fresh water makes up less than 3% of the world's water resources, and just 1% of that is readily available. About 70% of the world's freshwater reserves are frozen in Antarctica. Just 3% of it is extracted for human consumption. Agriculture uses roughly two thirds of all fresh water extracted from the environment.
Fresh water is a renewable and variable, but finite natural resource. Fresh water is replenished through the process of the natural water cycle, in which water from seas, lakes, forests, land, rivers and reservoirs evaporates, forms clouds, and returns inland as precipitation. Locally, however, if more fresh water is consumed through human activities than is naturally restored, this may result in reduced fresh water availability (or water scarcity) from surface and underground sources and can cause serious damage to surrounding and associated environments. Water pollution also reduces the availability of fresh water. Where available water resources are scarce, humans have developed technologies like desalination and wastewater recycling to stretch the available supply further. However, given the high cost (both capital and running costs) and - especially for desalination - energy requirements, those remain mostly niche applications.
A non-sustainable alternative is using so-called "fossil water" from underground aquifers. As some of those aquifers formed hundreds of thousands or even millions of years ago when local climates were wetter (e.g. from one of the Green Sahara periods) and are not appreciably replenished under current climatic conditions - at least compared to drawdown, these aquifers form essentially non-renewable resources comparable to peat or lignite, which are also continuously formed in the current era but orders of magnitude slower than they are mined.
Definitions
Numerical definition
Fresh water can be defined as water with less than 500 parts per million (ppm) of dissolved salts.
Other sources give higher upper salinity limits for fresh water, e.g. 1,000 ppm or 3,000 ppm.
Systems
Fresh water habitats are classified as either lentic systems, which are the stillwaters including ponds, lakes, swamps and mires; lotic which are running-water systems; or groundwaters which flow in rocks and aquifers. There is, in addition, a zone which bridges between groundwater and lotic systems, which is the hyporheic zone, which underlies many larger rivers and can contain substantially more water than is seen in the open channel. It may also be in direct contact with the underlying underground water.
Sources
The original source of almost all fresh water is precipitation from the atmosphere, in the form of mist, rain and snow. Fresh water falling as mist, rain or snow contains materials dissolved from the atmosphere and material from the sea and land over which the rain bearing clouds have traveled. The precipitation leads eventually to the formation of water bodies that humans can use as sources of freshwater: ponds, lakes, rainfall, rivers, streams, and groundwater contained in underground aquifers.
In coastal areas fresh water may contain significant concentrations of salts derived from the sea if windy conditions have lifted drops of seawater into the rain-bearing clouds. This can give rise to elevated concentrations of sodium, chloride, magnesium and sulfate as well as many other compounds in smaller concentrations.
In desert areas, or areas with impoverished or dusty soils, rain-bearing winds can pick up sand and dust and this can be deposited elsewhere in precipitation and causing the freshwater flow to be measurably contaminated both by insoluble solids but also by the soluble components of those soils. Significant quantities of iron may be transported in this way including the well-documented transfer of iron-rich rainfall falling in Brazil derived from sand-storms in the Sahara in north Africa.
In Africa, it was revealed that groundwater controls are complex and do not correspond directly to a single factor. Groundwater showed greater resilience to climate change than expected, and areas with an increasing threshold between 0.34 and 0.39 aridity index exhibited significant sensitivity to climate change. Land-use could affect infiltration and runoff processes. The years of most recharge coincided with the most precipitation anomalies, such as during El Niño and La Niña events. Three precipitation-recharge sensitivities were distinguished: in super arid areas with more than 0.67 aridity index, there was constant recharge with little variation with precipitation; in most sites (arid, semi-arid, humid), annual recharge increased as annual precipitation remained above a certain threshold; and in complex areas down to 0.1 aridity index (focused recharge), there was very inconsistent recharge (low precipitation but high recharge). Understanding these relationships can lead to the development of sustainable strategies for water collection. This understanding is particularly crucial in Africa, where water resources are often scarce and climate change poses significant challenges.
Water distribution
Saline water in oceans, seas and saline groundwater make up about 97% of all the water on Earth. Only 2.5–2.75% is fresh water, including 1.75–2% frozen in glaciers, ice and snow, 0.5–0.75% as fresh groundwater. The water table is the level below which all spaces are filled with water, while the area above this level, where spaces in the rock and soil contain both air and water, is known as the unsaturated zone. The water in this unsaturated zone is referred to as soil moisture.
Below the water table, the entire region is known as the saturated zone, and the water in this zone is called groundwater. Groundwater plays a crucial role as the primary source of water for various purposes including drinking, washing, farming, and manufacturing, and even when not directly used as a drinking water supply it remains vital to protect due to its ability to carry contaminants and pollutants from the land into lakes and rivers, which constitute a significant percentage of other people's freshwater supply. It is almost ubiquitous underground, residing in the spaces between particles of rock and soil or within crevices and cracks in rock, typically within of the surface, and soil moisture, and less than 0.01% of it as surface water in lakes, swamps and rivers.
Freshwater lakes contain about 87% of this fresh surface water, including 29% in the African Great Lakes, 22% in Lake Baikal in Russia, 21% in the North American Great Lakes, and 14% in other lakes. Swamps have most of the balance with only a small amount in rivers, most notably the Amazon River. The atmosphere contains 0.04% water. In areas with no fresh water on the ground surface, fresh water derived from precipitation may, because of its lower density, overlie saline ground water in lenses or layers. Most of the world's fresh water is frozen in ice sheets. Many areas have very little fresh water, such as deserts.
Freshwater ecosystems
Water is a critical issue for the survival of all living organisms. Some can use salt water but many organisms including the great majority of higher plants and most mammals must have access to fresh water to live. Some terrestrial mammals, especially desert rodents, appear to survive without drinking, but they do generate water through the metabolism of cereal seeds, and they also have mechanisms to conserve water to the maximum degree.
Challenges
The increase in the world population and the increase in per capita water use puts increasing strains on the finite resources availability of clean fresh water. The response by freshwater ecosystems to a changing climate can be described in terms of three interrelated components: water quality, water quantity or volume, and water timing. A change in one often leads to shifts in the others as well.
Limited resource
Minimum streamflow
An important concern for hydrological ecosystems is securing minimum streamflow, especially preserving and restoring instream water allocations. Fresh water is an important natural resource necessary for the survival of all ecosystems.
Water pollution
Society and culture
Human uses
Uses of water include agricultural, industrial, household, recreational and environmental activities.
Global goals for conservation
The Sustainable Development Goals are a collection of 17 interlinked global goals designed to be a "blueprint to achieve a better and more sustainable future for all". Targets on fresh water conservation are included in SDG 6 (Clean water and sanitation) and SDG 15 (Life on land). For example, Target 6.4 is formulated as "By 2030, substantially increase water-use efficiency across all sectors and ensure sustainable withdrawals and supply of freshwater to address water scarcity and substantially reduce the number of people suffering from water scarcity." Another target, Target 15.1, is: "By 2020, ensure the conservation, restoration and sustainable use of terrestrial and inland freshwater ecosystems and their services, in particular forests, wetlands, mountains and drylands, in line with obligations under international agreements."
See also
Notes
Subnotes
References
External links
The World Bank's work and publications on water resources
U.S. Geological Survey
Fresh Water National Geographic
Aquatic ecology
Hydrology
Water supply | Fresh water | [
"Chemistry",
"Engineering",
"Biology",
"Environmental_science"
] | 2,094 | [
"Hydrology",
"Fresh water",
"Ecosystems",
"Environmental engineering",
"Aquatic ecology",
"Water supply"
] |
62,558,712 | https://en.wikipedia.org/wiki/The%20Habitable%20Exoplanet%20Hunting%20Project | The Habitable Exoplanet Hunting Project is an international network of both professional and amateur astronomers. As of December 2019, the network comprises 32 observatories located worldwide, including universities such as the University of South Africa, the University of Saskatchewan in Canada, and the California Polytechnic State University.
The participants are searching for new potentially habitable exoplanets around non-flare G, K or M-type stars located within 100 light years. The initial list of targets consists of 10 stars that already have known transiting exoplanets outside the habitable zone.
The network is monitoring 24/7 each star at a time during several months. Despite G and K-type stars are the main targets of the project, the team is initially focusing on red dwarfs because it take less time to discard the existence of potentially habitable exoplanets around these type of stars.
Most of the observatories are able to detect transit depths as low as 0.1% and exoplanets with a radius of 0.7 Earth radii. To search for new exoplanets, the team is using two different methods: transit photometry and transit duration variation.
Overall, the project is a new approach to the quest for exoplanets in which a large network of astronomers located in the five continents have the time to continuously observe each star individually during long periods of time in the search for dips in brightness produced by transiting exoplanets.
As of December 2019, the network has already conducted observations on GJ 436 and GJ 1214, with a new campaign on GJ 3470 starting in January 2020. In July 2020, the group reported the discovery of GJ 3470 c.
See also
List of exoplanet search projects
References
Exoplanet search projects | The Habitable Exoplanet Hunting Project | [
"Astronomy"
] | 371 | [
"Astronomy projects",
"Exoplanet search projects"
] |
62,558,715 | https://en.wikipedia.org/wiki/Cranberry%20fruit%20rot | Cranberry fruit rot (CFR) is a disease complex of multiple fungal agents affecting the American cranberry (Vaccinium macrocarpon). Cranberry fruit rot can be categorized into field rot (rot occurring while growing and before harvest) and storage rot (occurring any time after harvest). The importance of field rot and fruit rot depends on how the cranberries will be processed after harvest. If cranberries are immediately processed after harvest, growers focus on preventing field rot while with fresh market cranberries, growers seek to prevent storage rot. There are 10-15 fungal pathogens known to cause cranberry fruit rot diseases, some active in only field rot, storage rot, or both. The majority of these fungal pathogens are ascomycetes, with the rest being deuteromycetes. There is no known bacterial pathogen that plays a role in CFR or any major disease on cranberry, potentially due to the low pH conditions on the cranberry fruit.
Host and symptoms
In cranberries, the fruit rot pathogens can infect before or after harvest. The symptoms of rot are related to a general softening and deterioration of the cranberry, which occur both in the field and in storage. Each specific rot disease that makes up the CFR disease complex is caused by specific pathogens (Table 1). An example is the field rot cotton ball caused by Monilinia oxycocci, common in Wisconsin, while bitter rot caused by Glomerella cingulate generally occurs in Massachusetts. However, these pathogens have been shown to not be entirely specific to their areas. These symptoms can often resemble other forms of fruit deterioration such as sunscald, hail damage, and temporal physiological breakdown.
Disease cycles
Due to the complexity and number of fungal pathogens involved in CFR, the specific disease cycles have yet to be fully studied. Researchers believe almost every fruit rot pathogen completes a disease cycle every 1–3 years. Researchers however have hypothesized 3 potential disease cycles taken by the pathogens. These 3 disease cycles rely heavily on leaves or stems, either debris or living, mainly because all berries are harvested.
Type 1. Fungal inoculum overwinters in plant debris in the soil surface. In the spring, the fungi produce fruiting bodies and infect developing plants. The main infection occurs when flowers bloom and during the early parts of fruit development.
Type 2. Fungi persist in living leaves then infect as the plant develops fruit while leaves drop.
Type 3. Fungal inoculum overwinter in plant debris and infect during cranberry harvest. When the floodwater is released during harvest, spores are dispersed and infect through potential wounds from equipment.
Management
The management of CFR can be complicated and varies due to the number of pathogens and the temporal aspect of fruit rot. Fungicides applied during the projected times of infection and on potential areas, such as flowers and after fruit set, are effective at deterring fruit rot. Due to the number of pathogens, general fungicides such as chlorothalonil, instead of specific-targeting fungicides, are more effective. However, fungicides can reduce fruit quality and fruit set in some cases, thus their use is often limited. Harvest can also play a role in reducing the risk of pathogens. Wet harvest using floodwater, although quicker and easier, can spread pathogens, which would increase chances of storage rot. Dry harvests can cause more damage to vines and take longer, but can reduce disease spread and decrease the potential of storage rot. Depending on the final use of cranberries, each harvest type can be beneficial. Sanding, a process where sand is laid on the field to stimulate root growth from the harvested cranberries, could actually play a role in covering up inoculum with plant debris, which may decrease the chances of field and storage rot. Resistance and biological controls have proved difficult to validate due to the disease complex being composed of different fungal pathogens.
References
Plant pathogens and diseases
Fruit rot | Cranberry fruit rot | [
"Biology"
] | 836 | [
"Plant pathogens and diseases",
"Plants"
] |
62,559,875 | https://en.wikipedia.org/wiki/V%20Crucis | V Crucis is a carbon star in the constellation Crux. A Mira variable, its apparent magnitude ranges from 8.7 to 11.1 over ays. The fact that this star's period is nearly equal to one year makes it hard to get good observational coverage over the entire cycle. Its near-infrared light curve shows a contribution from the first harmonic of the fundamental period.
References
Crux
Crucis, V
CD-57 4791
112319
063175
Mira variables
Carbon stars
J12563556-5753569
IRAS catalogue objects
Emission-line stars | V Crucis | [
"Astronomy"
] | 124 | [
"Crux",
"Constellations"
] |
62,560,011 | https://en.wikipedia.org/wiki/Genitourinary%20tract%20injury | The genitourinary tract, or simply the urinary tract, consists of the kidneys, ureters, bladder, and the urethra. The kidney is the most frequently injured. Injuries to the kidney commonly occur after automobile or sports-related accidents. A blunt force is involved in 80-85% of injuries. Major decelerations can result in vascular injuries near the kidney's hilum. Gunshots and knife wounds and fractured ribs can result in penetrating injuries to the kidney.
Pelvic fractures can damage the urethra and bladder.
Presentation
Comorbidity
In 90% of bladder injuries, there is a concurrent pelvic fracture. Pelvic bone fragments penetrate and perforate the bladder. Perforations can be either extraperitoneal or intraperitoneal. Intraperitoneal perforations allow for urine to enter the peritoneal cavity. Symptoms typically develop immediately if the urine is infected. Otherwise sterile urine may take days to cause symptoms.
Diagnosis
Hematuria in patients presenting after trauma
Blood in the urine after abdominal trauma suggests a urinary tract injury. Renal injuries are suggested by lower rib fractures. Bladder and urethral injuries are suggested by pelvic fractures.
Foley catheter
The urethral meatus should be examined after trauma. Blood at the urethral meatus precludes insertion of a foley catheter into the bladder. Erroneously placing a foley in this situation can result in infections of periprostatic and perivesical hematomas or conversion of a partial transection to a complete urethral transections. Blood at the urethral meatus suggests an injury to the urethra. Otherwise a foley catheter can be placed into the bladder and hematuria can be assessed for.
Abdominal imaging
Hemodynamically stable individuals should undergo further radiographic assessment. Abdominal computed tomography (CT) with contrast can detect retroperitoneal hematomas, renal lacerations, urinary extravasation, and renal arterial and venous injuries. A repeat scan ten minutes after the first is recommended.
Retrograde urethrography (RUG)
The purpose of this study is to identify and characterize injuries to the urethra. The tip of a small (12F) foley catheter is placed in the urethral meatus. The catheter remains fixed after 3 mL of water are instilled into the foley catheter's balloon. Radiographic films are taken as 20 mL of water-soluble contrast material are injected This outlines the urethra from the urethral meatus to the bladder neck. If injuries exist, the location can be determined.
Retrograde cystography
The purpose of this study is to identify bladder perforations. The bladder needs to be adequately distended with contrast medium. 300 mL or more are generally recommended. The study has two films. One film is taken when the bladder is adequately distended and filled with contrast. The next film is taken after the bladder is emptied without the assistance of a foley catheter.
Angiography
Helpful in identifying injuries to the kidney's parenchyma and vasculature.
Management
Genitourinary trauma
Urethral injuries
Management depends on what part of the urethra was injured and to what extent. The two broad anatomical separations are the posterior and anterior urethra. The posterior urethra includes the prostatic and membranous urethra. The anterior urethra includes the bulbous and pendulous portion.
Posterior urethra injuries
The membranous urethra can be separated from the prostate's apex after blunt trauma. The urethra should not be catheterized. Initial management should be the creation of a suprapubic cystostomy for urine drainage. The bladder should be opened in the midline so to facilitate inspection of bladder lacerations. Perforations can be closed with absorbable sutures. The suprapubic cystostomy remains in place for three months. Incomplete urethral disruptions heal spontaneously and the suprapubic cystostomy can be removed after three weeks for these injuries. Before removing a cystostomy, a voiding cystourethrography should demonstrate no urine extravasation. Delayed urethral reconstruction may be performed within 3 months. This typically entails a direct excision of the now strictured area and anastomosis of the bulbous urethra to the prostate's apex. A urethral catheter and suprapubic cystostomy should be left in place. These are removed within a month.
See also
Acute kidney injury
Genitourinary system
References
Genitourinary system
Injuries | Genitourinary tract injury | [
"Biology"
] | 988 | [
"Organ systems",
"Genitourinary system"
] |
62,563,135 | https://en.wikipedia.org/wiki/Phyllachora%20maydis | Phyllachora maydis is a plant pathogen causing ascomycete diseases in maize/corn, and is more commonly referred to as tar spot. Identified by the distinctive development of stroma, this pathogen in itself is of little economic importance in the production of corn. However, the accompanying fungal infection of Monographella maydis, identified by "fish-eye" lesions, was claimed to cause significant foliar damage and subsequently yield reduction. there is insufficient information about this pathogen and its management.
Symptoms and signs
This pathogen is an obligate parasite solely of the species Zea mays. The first symptoms are yellowing spots on both upper and lower leaf surfaces. Within the spot develops the characteristic black stromata over the ascomata, along with chlorosis of surrounding tissue. The chlorotic rings may be elliptical, circular, or may conjoin to form striping up to long. Some of the chlorotic tissue around the ascomata may become necrotic with darker edges, forming the indicative "fish-eye". The presence of these lesions is not universal, nor is the association of these lesions with M. maydis. Research is ongoing to determine the exact cause of these lesions. Symptoms have been recorded as early as V3, but are most commonly observed during R3-R6 on or below the ear leaves.
Disease cycle
Little is known about the progression of Phyllachora maydis. Presently, it is believed that the stromata overwinter on corn and soil residue. This is the primary inoculum that must be destroyed if the cycle is to be interrupted. Providing optimal temperatures, humidity and rainfall however, ascospores and conidia will be released in a gelatinous mass on the stromata. Both wind and precipitation are used to disperse the spores; however it is solely the ascospores that infect other plants. The role of conidia in the reproductive cycle is still unknown. The ascospores are released in bunches, and can travel as much as with wind dispersion. Following infection, new stromata can form within 12–15 days in infected tissue, producing additional ascospores and conidia. Given the polycyclic nature of this pathogen, as well as the ability to infect corn at any developmental stage, it is extremely hard to manage.
The pathogen progresses from the lower leaves to the upper leaves and husks. As many as 4000 clypeus may form on a leaf, resulting in 80% of affected leaf area. Given optimal conditions, total leaf death can occur in as little as twenty one days.
Distribution
Native to the Americas, from Mexico south, P. maydis appeared in the US for the first time in 2015 in Illinois and Indiana, then Florida, Iowa, Michigan, Ohio, Minnesota, Missouri, and Wisconsin in 2019. Tar spot appeared in Wisconsin in Green and Iowa counties in 2016, and had become a serious problem by 2018. When surveyed by the university and DATCP, it was found that 33 counties had recorded cases, and 77 of 79 fields surveyed, or 97 percent, showed signs.
Environment
In Latin America, the disease propagated quickly in temperatures ranging from with high humidity. Long periods of moisture on the leaf surface also increased the disease incidence. However, in the Midwest, it is still unknown as to the conditions that are preferred by the pathogen. During 2015 and 2018 when there was a high incidence of tar spot, the weather was warmer with high humidity and precipitation frequency, possibly attributing to the increased number of cases reported. Additional research is needed to understand the optimal conditions for propagation of this disease in the Midwest.
Management
A basic control measure that could be implemented is residue management. By tilling the field and rotating crops, this helps reduce the primary inoculum that overwinters on stalks and other residue. A biological control method that has shown potential is the infection with Coniothyrium phyllochorae by reducing lesion size due to hyperparasitism. Chemical control with one or two treatments of Fenpropimorph or Mancozeb applied every ten days were the most effective fungicides used in field trials. Although no cultivars currently exist that are immune to this pathogen, CIMMYT has developed 14 inbred lines in Latin America that are highly resistant. However, most hybrids used in the Midwest have proven susceptible.
Economic importance
Tar spot causes low ear weight, vivipary, and poor kernel fill resulting in up to a 30 bushel loss per acre. Increased lodging and stalk rot have also been associated with intense cases. Losses have become severe in some areas of the USA since 2018.
See also
Rhytisma acerinum, also called tar spot
References
External links
Phyllachorales
Fungal plant pathogens and diseases
Maize diseases
Fungus species | Phyllachora maydis | [
"Biology"
] | 997 | [
"Fungi",
"Fungus species"
] |
62,563,478 | https://en.wikipedia.org/wiki/Samsung%20Galaxy%20S20 | The Samsung Galaxy S20 is a series of Android-based smartphones developed, manufactured, and marketed by Samsung Electronics as part of its Galaxy S series. They collectively serve as the successor to the Galaxy S10 series. The first three smartphones were unveiled at Samsung's Galaxy Unpacked event on 11 February 2020 while the Fan Edition model was unveiled at Samsung's Galaxy Unpacked event on 23 September 2020.
The S20 series consists of the flagship Galaxy S20 and Galaxy S20+ models differentiated primarily by screen size, the larger camera-focused model, the Galaxy S20 Ultra, and the cheaper flagship model, the Galaxy S20 FE. Key upgrades over the previous model, in addition to improved specifications, include a display with a 120 Hz refresh rate, an improved camera system supporting 8K video recording (7680×4320) for the first three models and a super-resolution zoom of 30–100x, depending on the model.
The first three phones were released in the United States on 6 March 2020 and in Europe on 13 March 2020, while the Fan Edition was released globally on 2 October 2020. The Galaxy S20 FE, S20, S20+, and S20 Ultra launch prices started at $699, $999, $1,199 and $1,399, respectively.
It is the first smartphone lineup to receive USB fast-charger certification from the USB Implementers Forum (USB-IF).
In May, a rugged variant for military use named "Tactical Edition" was released.
The Galaxy S20 was succeeded by the Galaxy S21, which was announced on 14 January 2021. In April 2022, following the release of its new flagship, the Galaxy S22, Samsung released a refreshed version of the Galaxy S20 FE known as the Galaxy S20 FE 2022, which has the same processor as the Galaxy S20 series. It has 6 GB of RAM and 128 GB of internal storage and ships with One UI 4 based on Android 12.
History
The title of the phone was originally presumed to be the Galaxy S11, due to it being the logical extension from its predecessor, the Galaxy S10. However, successive leaks in January 2020 revealed the title of the phone to be the Galaxy S20, because it was released in the year of 2020. In addition, details regarding the phone were leaked widely before the release, to the extent that almost all details regarding the specifications and design of the phone were known before the release. Leaker Max Weinbach obtained the actual phone a month before the release, confirming everything the community already guessed. Commentators remarked that by February, "almost everything the company is planning to introduce has already leaked out." In addition to charts on the phone's specifications, marketing material and images of the phones themselves in real life were leaked.
Design
The Galaxy S20 series has a design similar to the Samsung Galaxy Note 10, with an Infinity-O display (first introduced on the Galaxy S10) containing a circular punch-hole in the top center this time for the frontal selfie camera. In a departure from past Galaxy S designs, the rear camera array is not centered, but located in the corner with a rectangular protrusion similar to that of the iPhone 11 and the Google Pixel 4. The S20 and S20FE houses three cameras while the S20+ has four cameras in the bump, while the S20 Ultra houses four cameras in a larger bump. S20 phones sold in Europe had news aggregator upday in partnership with Axel Springer SE preinstalled, triggering notifications. Global color options for the first three phones are Cloud Pink, Cloud White, Cloud Blue, Cosmic Grey and Cosmic Black while the Fan Edition has Cloud Lavender, Cloud Mint, Cloud Navy, Cloud White, Cloud Red, and Cloud Orange. Cosmic Grey is available in all size variants except for the S20 FE, while Cosmic Black is limited to the S20+ and S20 Ultra, Cloud Blue is limited to the S20 and S20+, and Cloud Pink is exclusive to the S20. For the S20+, Prism Blue, is exclusively sold in Korea, Best Buy in the United States and through T-Mobile, Samsung Nederland and Tele2 in the Netherlands, while Aura Red is exclusive to Korea Telecom, Vodafone UK, Malaysia, and United Arab Emirates. Cloud White availability varies by country; in the United States it is exclusive to Verizon for the S20 with Ultrawide Band support. The S20 is sold in Italy, the S20+ is sold in Italy and Spain, and the S20 Ultra is sold in China and Germany.
In June 2020, Verizon released the Galaxy S20 5G UW (Ultra Wideband). Differences from the S20 include the addition of mmWave, only 8 GB of RAM (compared to the usual 12 GB), and no microSD slot. Moreover, Samsung released the Galaxy S20+ 5G BTS Edition in the summer of 2020, with the color "Haze Purple."
Specifications
Hardware
Chipsets
The S20 line comprises three models with various hardware specifications; international models of the S20 utilize the Exynos 990 system-on-chip, while the U.S., Canadian, Korean, Chinese and Japanese models utilize the Qualcomm Snapdragon 865.
Display
A 1440p "Dynamic AMOLED 2X" is featured with HDR10+ support and "dynamic tone mapping" technology with the exception of the S20 FE which utilizes a more traditional 1080p "Super AMOLED" display with HDR10+ support and "dynamic tone mapping" technology. The S20, S20 FE, and S20+ have a 6.2-inch, 6.5-inch, and 6.7-inch display, respectively, while the S20 Ultra has a 6.9-inch display. Except for the S20 FE, displays have curved sides that slope over the horizontal edges of the device. All devices utilizes a wider 20:9 aspect ratio in addition to a 120 Hz refresh rate double that of the S10. The S20, S20+, and S20 Ultra utilizes an ultrasonic in-screen fingerprint sensor while the S20 FE utilizes a more traditional optical in-screen fingerprint sensor.
Storage
The base amount of RAM is 6 GB with an additional 8 GB option for the S20 FE, while the base amount is 8 GB, with an additional 12 GB option for the S20 & S20+ and a 16 GB option for the S20 Ultra. 128 GB of internal storage is standard with the S20 FE offering a 256 GB option while the S20+ & S20 Ultra also offers 256 GB and 512 GB options, with up to 1 TB of expansion via the microSD card slot. Verizon's Galaxy S20 5G UW model is not equipped with a microSD slot.
Batteries
The S20, S20 FE, S20+, & S20 Ultra contain non-removable 4000 mAh, 4500 mAh, 4500 mAh, and 5000 mAh Li-Po batteries respectively, and Qi inductive charging is supported at up to 15 W as well as the ability to charge other Qi-compatible devices from the S20's own battery power, which is branded as “Samsung PowerShare”. Wired charging is supported over USB-C at up to 25 W for the S20, S20 FE, & S20+ and 45 W for the S20 Ultra.
They support reverse charging at 4.5 W.
Connectivity
The S20 series comes with 5G standard connectivity, though some regions may have special LTE variants. However, only Verizon models are compatible with higher-speed millimeter-wave networks. The 3.5 mm audio jack has been omitted entirely.
Cameras
The cameras on the Galaxy S20 series improved considerably over its predecessors, although unlike the S9 and S10, the aperture on the main lens is fixed. While the megapixels of the main and ultra wide sensors remained unchanged on the S20 and S20+, the telephoto sensor received some improvements. The 64-megapixel telephoto camera, branded as “Space Zoom”, supports 3X hybrid optical zoom (branded as "Hybrid Optic Zoom") and 30X digital zoom at 64 megapixels on the new telephoto sensor instead of 12 megapixels at two times on the S10 and 30 times digitally (branded as "Super-Resolution Zoom").
The S20+ receives a time-of-flight sensor (branded as "DepthVision Camera") in addition to the regular S20's cameras. The Galaxy S20 Ultra has a quadruple lens setup that supports 4X optical zoom and 100X digital zoom, with a 108-megapixel wide image sensor, a 12-megapixel ultra-wide sensor and a 48-megapixel periscope telephoto sensor accompanied by a time-of-flight sensor. Both the wide-angle and telephoto sensors use pixel binning to output higher quality images at a standard resolution, with the wide-angle sensor using Nonacell technology which groups 3x3 pixels to capture more light.
The front camera is able to record video footage at 2160p.
A new camera mode was introduced called Single Take, which allows users to capture photos or videos at the same time with different sensors automatically. The S20, S20+, and S20 Ultra can also record 8K videos at 24 fps with a bit rate of 80 Mbps, which will consume about 600 MB of storage per minute. On the S20 and S20+, this is enabled by the 64 MP telephoto sensor, whereas the S20 Ultra's 108 MP wide sensor natively supports 8K video.
Supported video modes
The Samsung Galaxy S20 series supports the following video modes:
8K@24 fps (not available for the S20 FE)
4K@30/60 fps
1080p@30/60 fps
1080p@240 fps
720p@960 fps (720p480fps interpolates to 720p960fps on S20 Ultra)
All models can record at 720p30, 1080p30 or 4k30 with HDR10+, they can record with HEVC codec without HDR10+
Software
All four phones initially ran on Android 10 and Samsung's custom skin One UI 2.1. In early December 2020, Samsung began releasing the Android 11 update with One UI 3 to all models. In January 2022, all four phones have received the One UI 4 update based on Android 12. As of May 2024, the S20 also supports updating to Android 13.
Software support
On 18 August 2020, Samsung revealed that all variants of the S20 series would be supported for three generations of Android software updates, and 4 years of security updates. In April 2024, however, the company extended support for a 5th year, moving from monthly to quarterly.
Known issues
Even before the general release, reviewers have seen autofocus and skin smoothing issues with the cameras, especially with the Galaxy S20 Ultra. Samsung is working on a fix, but the Exynos model continues to have autofocus issues after an update that was supposed to fix them.
Galaxy S20 Ultra can only record at 720p480fps and it interpolates with AI to 720p960fps, Galaxy S20 and S20+ can record at 720p960fps.
Users have reported that the Snapdragon version has GPS lock issues. The Exynos model is also known to have heating issues. Some devices also suffer from green display tint issues after a software update. The camera glass has been reported of spontaneously cracking, particularly on the Ultra version.
Some users reported instances of the Galaxy S20 FE suffering from touchscreen issues such as "ghost" touches and jittery movement when scrolling or zooming. Samsung attempted to fix the issue with several updates.
Some users in India reported that after being updated to One UI 4.01, a vertical line started appearing on the front display. These devices were out of warranty and Samsung India concluded it was user error. They charged around 16,000 INR to those users who were looking for a screen replacement. Around a thousand affected users tweeted about it asking for help and others decided to take legal action. Samsung India has still failed to acknowledge this issue.
Samsung Galaxy S20 Tactical Edition
The Samsung Galaxy S20 Tactical Edition (TE) is a touchscreen-enabled, slate-format Android smartphone designed, developed, and marketed by Samsung Electronics.
The device is built matching the needs of operators in the federal government and Department of Defense. The mobile is Commercial Solutions for Classified Program (CSfC) component approved, with support to night vision, stealth mode, drone feeds and laser range finders. It can connect to tactical radios and mission systems, and runs applications like Battlefield assisted trauma distributed observation kit (BATDOK) etc.
Notes
External links
Official website
See also
Digital zoom § iZoom
Samsung Galaxy
Samsung Galaxy S series
Exynos
List of Qualcomm Snapdragon processors
AMOLED
References
External links
Android (operating system) devices
Samsung Galaxy
Discontinued Samsung Galaxy smartphones
Discontinued flagship smartphones
Samsung smartphones
Mobile phones introduced in 2020
Mobile phones with multiple rear cameras
Mobile phones with 4K video recording
Mobile phones with 8K video recording | Samsung Galaxy S20 | [
"Technology"
] | 2,783 | [
"Discontinued flagship smartphones",
"Flagship smartphones"
] |
62,564,349 | https://en.wikipedia.org/wiki/NGC%20605 | NGC 605 is a lenticular galaxy in the constellation Andromeda, which is about 234 million light-years from the Milky Way. It was discovered on October 21, 1881 by the French astronomer Édouard Jean-Marie Stephan.
SIMBAD lists NGC 605 as an active galaxy nucleus candidate.
One supernova has been observed in NGC 605: SN 2024nnu (type Ia, mag. 15.6).
References
0605
01128
005891
+07-04-004
Lenticular galaxies
Andromeda (constellation)
Astronomical objects discovered in 1881
Discoveries by Édouard Stephan | NGC 605 | [
"Astronomy"
] | 125 | [
"Andromeda (constellation)",
"Constellations"
] |
62,564,371 | https://en.wikipedia.org/wiki/NGC%20770 | NGC 770 is an elliptical galaxy in the constellation Aries. It is around 120 million light years from the Milky Way and has a diameter of around . NGC 770 is gravitationally linked to NGC 772. The galaxy was discovered on November 3, 1855 by RJ Mitchell.
References
External links
770
Elliptical galaxies
Aries (constellation)
007517 | NGC 770 | [
"Astronomy"
] | 71 | [
"Aries (constellation)",
"Constellations"
] |
62,564,468 | https://en.wikipedia.org/wiki/Luo%20Qingming | Luo Qingming (; born January 1966) is a Chinese scientist currently serving as president of Hainan University since September 2018.
Education
Luo was born in Qichun County, Hubei in January 1966. He obtained his Bachelor of Engineering degree from Xidian University in 1986. He received his Master of Science in optics degree and Doctor of Engineering in physical electronics and optoelectronics degree from Huazhong University of Science and Technology in 1986 and 1993, respectively. From 1995 to 1997 he did post-doctoral research at the Perelman School of Medicine at the University of Pennsylvania.
Career
After graduating from Huazhong University of Science and Technology, he taught there. In February 1997 he founded the Biomedical Photonics Research Center. In 1999 he became vice-chairman of its College of Life Science and Technology, rising to chairman in 2004. He served as chairman of College of Optoelectronic Science and Engineering between July 2007 and June 2012. In August 2007 he was promoted to become vice-president of Huazhong University of Science and Technology, he remained at the position until September 2018, when he was transferred to Haikou, capital of south China's Hainan province, as president of Hainan University.
Honors and awards
2007 Fellow of the Society of Photo-Optical Instrumentation Engineers
2010 State Natural Science Award (Second Class)
2012 Fellow of the Institution of Engineering and Technology
Fellow of The Optical Society
November 22, 2019 Academician of the Chinese Academy of Sciences
References
1966 births
People from Qichun County
Living people
Xidian University alumni
Huazhong University of Science and Technology alumni
Academic staff of Hainan University
Presidents of Hainan University
Members of the Chinese Academy of Sciences
Fellows of the Institution of Engineering and Technology
Fellows of Optica (society) | Luo Qingming | [
"Engineering"
] | 357 | [
"Institution of Engineering and Technology",
"Fellows of the Institution of Engineering and Technology"
] |
62,565,170 | https://en.wikipedia.org/wiki/NGC%20690 | NGC 690 is an intermediate spiral galaxy located in the constellation Cetus about 236 million light-years from the Milky Way. It was discovered by the American astronomer Francis Leavenworth in 1885.
References
External links
690
Intermediate spiral galaxies
Cetus
006587 | NGC 690 | [
"Astronomy"
] | 53 | [
"Cetus",
"Constellations"
] |
62,565,191 | https://en.wikipedia.org/wiki/NGC%20622 | NGC 622 is a barred spiral galaxy located in the constellation Cetus about 234 million light-years from the Milky Way. It was discovered by British astronomer William Herschel in 1785.
References
External links
622
Barred spiral galaxies
Cetus
01143
Markarian galaxies
005939 | NGC 622 | [
"Astronomy"
] | 58 | [
"Cetus",
"Constellations"
] |
62,565,215 | https://en.wikipedia.org/wiki/NGC%20801 | NGC 801 is a spiral galaxy with an active galaxy core in the constellation Andromeda. It is estimated to be 174 million light-years from the Milky Way and has a diameter of approximately 174,400 light-years. The object was discovered on September 20, 1885 by the American astronomer Lewis A. Swift.
References
801
Spiral galaxies
Andromeda (constellation)
007847 | NGC 801 | [
"Astronomy"
] | 81 | [
"Andromeda (constellation)",
"Constellations"
] |
77,939,986 | https://en.wikipedia.org/wiki/Reparameterization%20trick | The reparameterization trick (aka "reparameterization gradient estimator") is a technique used in statistical machine learning, particularly in variational inference, variational autoencoders, and stochastic optimization. It allows for the efficient computation of gradients through random variables, enabling the optimization of parametric probability models using stochastic gradient descent, and the variance reduction of estimators.
It was developed in the 1980s in operations research, under the name of "pathwise gradients", or "stochastic gradients". Its use in variational inference was proposed in 2013.
Mathematics
Let be a random variable with distribution , where is a vector containing the parameters of the distribution.
REINFORCE estimator
Consider an objective function of the form:Without the reparameterization trick, estimating the gradient can be challenging, because the parameter appears in the random variable itself. In more detail, we have to statistically estimate:The REINFORCE estimator, widely used in reinforcement learning and especially policy gradient, uses the following equality:This allows the gradient to be estimated:The REINFORCE estimator has high variance, and many methods were developed to reduce its variance.
Reparameterization estimator
The reparameterization trick expresses as:Here, is a deterministic function parameterized by , and is a noise variable drawn from a fixed distribution . This gives:Now, the gradient can be estimated as:
Examples
For some common distributions, the reparameterization trick takes specific forms:
Normal distribution: For , we can use:
Exponential distribution: For , we can use:Discrete distribution can be reparameterized by the Gumbel distribution (Gumbel-softmax trick or "concrete distribution").
In general, any distribution that is differentiable with respect to its parameters can be reparameterized by inverting the multivariable CDF function, then apply the implicit method. See for an exposition and application to the Gamma Beta, Dirichlet, and von Mises distributions.
Applications
Variational autoencoder
In Variational Autoencoders (VAEs), the VAE objective function, known as the Evidence Lower Bound (ELBO), is given by:
where is the encoder (recognition model), is the decoder (generative model), and is the prior distribution over latent variables. The gradient of ELBO with respect to is simplybut the gradient with respect to requires the trick. Express the sampling operation as:where and are the outputs of the encoder network, and denotes element-wise multiplication. Then we havewhere . This allows us to estimate the gradient using Monte Carlo sampling:where and for .
This formulation enables backpropagation through the sampling process, allowing for end-to-end training of the VAE model using stochastic gradient descent or its variants.
Variational inference
More generally, the trick allows using stochastic gradient descent for variational inference. Let the variational objective (ELBO) be of the form:Using the reparameterization trick, we can estimate the gradient of this objective with respect to :
Dropout
The reparameterization trick has been applied to reduce the variance in dropout, a regularization technique in neural networks. The original dropout can be reparameterized with Bernoulli distributions:where is the weight matrix, is the input, and are the (fixed) dropout rates.
More generally, other distributions can be used than the Bernoulli distribution, such as the gaussian noise:where and , with and being the mean and variance of the -th output neuron. The reparameterization trick can be applied to all such cases, resulting in the variational dropout method.
See also
Variational autoencoder
Stochastic gradient descent
Variational inference
References
Further reading
Machine learning
Stochastic optimization | Reparameterization trick | [
"Engineering"
] | 796 | [
"Artificial intelligence engineering",
"Machine learning"
] |
77,942,360 | https://en.wikipedia.org/wiki/DRC-5593 | DRC-5593 (N-Acetyl-4-cyclohexylmethylcyclohexylamine) is a powerful lachrymatory agent that was suggested as an animal repellant and riot control agent.
See also
Capsaicin
References
Cyclohexyl compounds
Cyclohexylamines
Acetamides
Lachrymatory agents
Riot control agents | DRC-5593 | [
"Chemistry"
] | 82 | [
"Chemical weapons",
"Organic compounds",
"Riot control agents",
"Lachrymatory agents",
"Organic compound stubs",
"Organic chemistry stubs"
] |
77,943,562 | https://en.wikipedia.org/wiki/Fourcade-Figueroa%20Object | The Fourcade-Figueroa Object, also known as ESO 270-17 or the FF galaxy, is an edge-on irregular galaxy located in the constellation of Centaurus. It is located 51 million light years from Earth. The galaxy has a luminosity class of V with a broad HI line. It is also classified as a low-surface brightness galaxy (LSB) and is located near from the radio galaxy NGC 5128, also known as Centaurus A.
Discovery and observation
The Fourcade-Figueroa Object was discovered in May 1970, by two astronomers, Carlos Raúl Fourcade from Argentina and Egardo Javier Figueroa from Chile while capturing the Centaurus A region with a Curtis-Schmidt camera at Cerro Tololo Inter-American Observatory. This discovery prompted both Fourcade and Figueroa to name the object after themselves.
For seven years, the Fourcade-Figueroa Object appears to be diffused and elongated. According to Dottori and Fourcade, it is said to be associated with Centaurus A as a shred (a galactic remnant resulting from a galaxy merger). In the year 1978, Graham reached a conclusion and found the object is a late-type galaxy. In the Second Reference Catalogue, the Fourcade-Figueroa Object has been catalogued as A 1332–45. It is very faint to observe, even using an amateur telescope.
Characteristics
The Fourcade-Figueroa Object seems to be a stellar remanent caused by a progenitor spiral galaxy undergoing a galaxy shredding process with Centaurus A. As a result, a dwarf elliptical galaxy, NGC 5237, is created from its core while the rest of the galaxy's material became the object, it is known today. The Fourcade-Figueroa Object is found to be large with knots of resolved stars extending along the major axis by a distance of 15 arc minutes. According to Holmberg, the Fourcade-Figueroa Object has a dimensions of 17 x 2 arcmin. It has an inclination angle between 86 and 90 degrees and is surrounded by a cloud of neutral hydrogen, that is dissolving its mass by 5%.
The Fourcade-Figueroa Object is classified as a proto-typical superthin galaxy. When observed at both optical and HI wavelengths, the object is disrupted when seen towards the northwest side. It is also known to have its thickness of gas showing a steep gas flare in agreement with the stellar disk edge. Based on the Navarro-Frenk-White dark matter distribution and a pseudo-isothermal halo models, the Fourcade-Figueroa Object contains a compact core of dark matter. This indicates the reason why the galaxy has a superthin stellar disk structure.
References
Centaurus
Low surface brightness galaxies
Astronomical objects discovered in 1970
047847
270-017 | Fourcade-Figueroa Object | [
"Astronomy"
] | 582 | [
"Centaurus",
"Constellations"
] |
77,943,782 | https://en.wikipedia.org/wiki/Vladimir%20V.%20Tikhomirov%20History%20of%20Geology%20Award | Vladimir V. Tikhomirov History of Geology Award is a geological and historical medal of the International Union of Geological Sciences (IUGS). It is the only international award for scientific contributions and achievements in the field of history of geological sciences.
History
Named in honor of the Soviet historian of geology Vladimir Vladimirovich Tikhomirov (1915–1994) — the organizer and first president of the International Commission on the History of Geological Sciences (INHIGEO) in 1967. Nominations for the award are made by the International Commission on the History of Geological Sciences (INHIGEO), approved by the International Union of Geological Sciences (IUGS).
In 2012, the medal was established by the International Union of Geological Sciences for work on the history of geology. The medal is made of bronze.
Since 2020, the medal with a diameter of 10 cm is made of Armenian obsidian.
Awards
The medal is awarded every four years during the International Geological Congress.
Throughout history, the medal has been awarded to:
2012 — Hugh Torrens, United Kingdom
2016 — Martin J. S. Rudwick, United Kingdom
2020 — David Branagan (Branagan David Francis (1930–2022)), Australia
2024 — Kenneth L. Taylor United States
References
Links
Longtime OU Professor to Receive International Award in Geology History (2024).
Awards established in 2012
History of geology
Commission on the History of Geological Sciences
Geology awards
Earth sciences | Vladimir V. Tikhomirov History of Geology Award | [
"Technology"
] | 292 | [
"Science and technology awards",
"Lists of science and technology awards"
] |
77,944,540 | https://en.wikipedia.org/wiki/Enzo%20Marinari | Enzo Marinari (born on July 7, 1957, in Avellino) is an Italian theoretical and computational physicist. He has contributed to introducing several new algorithms in computational physics, such as Parallel Tempering, the SU(N) updating method and Constraint Allocation Flux Balance Analysis (CAFBA). He is a professor at the Physics Department of the Sapienza University of Rome.
Education and career
Enzo Marinari got his physics degree at the Sapienza University of Rome in 1980. Until 1984 he worked as a staff scientist at the Theoretical Physics Institute of the CEA Saclay, in France. In 1988 he was nominated Associate Professor at the University of Rome Tor Vergata and in 1994 he became a full professor at the University of Cagliari. Since 1999 he is a full professor at the Physics Department of the Sapienza University of Rome in Italy.
From 1992 until 1994 he was contemporarily the Physics Director for the Northeast Parallel Architecture Center (NPAC) in Syracuse, NY, USA. During the period 2004-2011, he was the Scientific Director for physics of the Institute for Biocomputation and Physics of Complex Systems (BIFI) at the University of Zaragoza, Spain.
During his career Enzo Marinari has done research in
different fields of physics, such as particle physics (QCD, string theory), statistical physics (spin glasses, disordered and complex systems, phase transitions, temperature chaos) and biophysics (metabolic and neural networks).
He has been one of the founding members of the Spanish-Italian Janus collaboration and of the Italian APE collaboration, both promoting the use of computational methods in research in physics.
He has written and edited several books
and plays an active role in explaining science and its applications on mainstream media channels.
Recognitions
In 1978 and 1979 Enzo Marinari received the Borsa Persico of the Accademia dei Lincei. In 1988 he was elected as best physicist under the age of 35 by the Accademia dei Lincei.
In 1992 he received an essay prize from the Gravity Research Foundation.
References
External links
Personal Homepage
Living people
1957 births
20th-century Italian physicists
21st-century Italian physicists
Academic staff of the Sapienza University of Rome
Statistical physicists | Enzo Marinari | [
"Physics"
] | 458 | [
"Statistical physicists",
"Statistical mechanics"
] |
77,944,608 | https://en.wikipedia.org/wiki/IC%204687 | IC 4687 known as IRAS 18093-5744 or F18093-5744, is an Sb spiral galaxy located in the constellation of Pavo. It is located 250 million light years from Earth and was discovered by Royal Harwood Frost on August 1, 1904, who described the object "as brighter middle with magnitude of 14. It has a surface brightness of 12.5.
Characteristics
IC 4687 is classified as a luminous infrared galaxy. It has an infrared-luminosity of 1011.3 LΘ, compatible with a star formation rate of 30 MΘ yr−1. Through it has an energy output dominated by its star formation, the galaxy has a weak active galactic nucleus.
The regions of IC 4687 are also known to contain high amounts of molecular gas surface densities of log ΣH2 (MΘ pc−2) = 2.9 ± 0.2. In additional, the galaxy is known to produce stars at a rapid rate when compared to normal star forming galaxies with the regions having log ΣSFR (MΘ yr−1 kpc−2) = 0.7 ± 0.4. This units are considered ~ 10 factor higher when compared to extreme values of nearby galaxies. Not to mention, IC 4687 has a velocity field mainly controlled by rotation. It also has a defined kinematic center that is synchronous with its nucleus.
IC 4687 forms an interacting galaxy trio with two other galaxies, IC 4686 and IC 4689. Both of these galaxies are located ~ 10 and ~ 20 kiloparsecs away from IC 4687 and are classified as spiral-like with their velocity fields influenced by kinematic and rotation centers. Because of its close merger with IC 4686, a starburst and wolf-raynet galaxy, IC 4687 appears distorted. The Hubble images shows the galaxy has a distorted morphology with interstellar dust and gas apparently obscuring its companion. Not to mention, IC 4687 has large curly tidal tail as a result of the merger. It is possible the weak interaction from IC 4686 might triggered its starburst.
References
External links
at SIMBAD
4687
Pavo (constellation)
Barred spiral galaxies
061602
140-IG10
IRAS catalogue objects
Luminous infrared galaxies
Interacting galaxies
Discoveries by Royal Harwood Frost
Astronomical objects discovered in 1904 | IC 4687 | [
"Astronomy"
] | 490 | [
"Constellations",
"Pavo (constellation)"
] |
77,944,939 | https://en.wikipedia.org/wiki/Yodh%20Prize | The Yodh Prize, awarded every two years, honors a scientist for that scientist's outstanding career in cosmic ray research.
Background
The award ceremony takes place at the International Cosmic Ray Conference (ICRC). The recipient is selected by the Commission on Astroparticle Physics of the International Union of Pure and Applied Physics (IUPAP) on behalf of the University of California Irvine Foundation, which sponsors the prize. The prize winner gives a talk at UC Irvine's department of physics and astronomy. In 1998 Gaurang Bhaskar Yodh (1928–2019) and his wife Kanwal G. Yodh (1928–2015) endowed the prize to the UC Irvine Foundation.
The inaugural winner of the Yodh Prize was Reuven Ramaty. He was severely ill with amyotrophic lateral sclerosis (ALS) at the time in April 2001 of his selection by the IUPAP and died about one week after he was informed of the honor.
Yodh Prize recipients
References
Awards established in 1998
Physics awards
IUPAP | Yodh Prize | [
"Technology"
] | 212 | [
"Science and technology awards",
"Physics awards"
] |
77,952,890 | https://en.wikipedia.org/wiki/Poop%20Map | Poop Map is a social app where users can track on a map where and when they defecate. In addition to logging location and time of each bowel movement, users can also add a photo, "like" other users' logs, and rate each account. The social elements of the app allow for groups of users to create a competitive league. Certain behaviors unlock achievements in-app.
Development
The app was created by app developer Nino Uzelac. It was launched in July 2013.
Popularity
The app charted at number one on the Apple App Store charts in 2021 after going viral on TikTok. As of September 2024, the app has a 4.8 rating on the App Store and more than 58,000 ratings. It also has more than one million downloads on the Google Play Store.
Poop Map is notably popular among hikers, and has been written about in the outdoors magazine Outside.
References
Application software
2013 software
Defecation | Poop Map | [
"Biology"
] | 194 | [
"Excretion",
"Defecation"
] |
77,952,999 | https://en.wikipedia.org/wiki/Saint%20Petersburg%20State%20University%20Mathematics%20and%20Mechanics%20Faculty | The Saint Petersburg State University Mathematics and Mechanics Faculty is a research and education center in the fields of mathematics, mechanics, astronomy, and computer science.
Early history
In 1701 Tsar Peter I issued a decree founding a school of mathematical and navigation sciences. In 1724 the Russian Academy of Sciences, the , and the Academic Gymnasium were founded. This marked the beginning of the famous Saint Petersburg Mathematical School. When Saint Petersburg University was founded in 1819, the department of mathematics at the created four departments: pure mathematics, applied mathematics, astronomy, and physics. Gradually expanding, this department survived for over a century. By 1930, the Faculty of Physics and Mathematics had become a formal union of independent departments: mathematics, mechanics, astronomy-geodesy, physics, and geography (in 1929–1930, the State University Institute of Chemistry and the had already separated from it). In 1931, the university's faculties were abolished and replaced by sectors: mathematics and mechanics, physics, geophysics, soil science and botany, physiology, and zoology. In 1932–33, the sectors were transformed back into faculties: mathematics and mechanics, physics, biology, geology-soil-geography, and chemistry.
History
The first dean of the Faculty of Mathematics and Mechanics (technically, head of the corresponding sector) in 1931 was a postgraduate student of Grigorii Fikhtengol'ts, O. A. Beloglavek. In 1933, Mikhail Subbotin became the dean, leading the faculty until World War II.
In February 1942 Professor was appointed dean but was arrested and repressed shortly thereafter.
In 1945 the faculty was granted the premises of the former Bestuzhev Courses (10th Line, 33). A branch of the faculty was located at 14th Lines of Vasilyevsky Island, building 29.
In 1957 a Computing Center was established at the faculty.
In 1979 the faculty moved to the in the suburbs of Saint Petersburg, in the Petergof district.
Until the 2011 reorganization the faculty included scientific institutions—the , the , and the Research Institute of Information Technology.
In 2019 the Faculty of Mathematics and Computer Science separated from the Faculty of Mathematics and Mechanics, along with the building on 14th Lines of Vasilyevsky Island on Vasilyevsky Island.
Departments
The faculty consists of 22 departments, one interfaculty department, postgraduate and doctoral programs, the Intel research and educational laboratory, 9 service departments, a scientific library, an archive, and the scientific center "Dynamics." As of October 15, 2009, the faculty had 378 teachers, including 126 professors and 178 associate professors.
Deans
Olga Beloglavek (1931–1932)
Mikhail Subbotin (1933–1941)
Nikolai Roze (1942)
Ogorodnikov, Kirill (1942–1948)
Nikolai Yerugin (1949)
Pyotr Gorshkov (1949–1951)
Dmitry Faddeev (1952–1954)
Nikolai Polyakhov (1954–1965)
Sergey Vallander (1965–1973)
Zenon Borevich (1973–1984)
Sergey Ermakov (1984–1988)
Gennady Leonov (1988–2018)
Alexander Razov (2018–2022)
Acting Dean Kustova, Elena Vladimirovna (2022–present)
Alumni
Mikhail Gromov
Grigori Perelman (1982–1987)
References
External links
Official website of the faculty
Student website of the Faculty of Mathematics and Mechanics at SPbSU
Mathematics and Mechanics Weeks
I. Grekova, Leningrad University in the 1920s
S. Ivanov "From the History of the Faculty of Mathematics and Mechanics" Saint Petersburg: Everest – Third Pole, 1997
Nazarov A.I., "On the Bachelor's Curriculum in Mathematics at Saint Petersburg State University," Mathematics in Higher Education, No. 11, 2013, pp. 63–66
Leonov, G.A., Terekhov, A.N., Novikov, B.A., Kruk, E.A., Nesterov, V.M., "Creation of a Scientific and Educational IT Cluster at the Faculty of Mathematics and Mechanics at SPbSU Based on Modern Fundamental Mathematics," Computer Tools in Education, No. 2: 42–57, 2017
Minutes of the SPbSU Academic Council Meeting (27.05.2019): On the Initiative to Create the Faculty of Mathematics and Computer Science
Mathematics departments
Mechanical engineering schools | Saint Petersburg State University Mathematics and Mechanics Faculty | [
"Engineering"
] | 892 | [
"Mechanical engineering schools",
"Mechanical engineering organizations",
"Engineering universities and colleges"
] |
77,954,525 | https://en.wikipedia.org/wiki/3-Chlorostyrylcaffeine | 3-Chlorostyrylcaffeine (CSC), or 8-(3-chlorostyryl)caffeine (8-CSC), is a potent and selective adenosine A2A receptor antagonist which is used in scientific research.
It has 520-fold selectivity for the adenosine A2A receptor over the adenosine A1 receptor (Ki = 54nM and 28,000nM for the rat receptors, respectively). Its affinities for the adenosine A2B and A3 receptors are similarly low (Ki = 8,200nM and >10,000nM, respectively).
CSC has been found to reverse the catalepsy induced by the dopamine D1 receptor antagonist SCH-23390 and the dopamine D2 receptor antagonists raclopride and sulpiride in animals.
The drug was one of the first selective adenosine A2A receptor antagonists to be developed. However, in addition to its adenosine receptor antagonism, CSC was subsequently found to be a potent monoamine oxidase B (MAO-B) inhibitor (Ki = 80.6nM for baboon MAO-B). CSC was first described in the scientific literature by 1993.
See also
DMPX
Istradefylline
MSX-3
References
3-Chlorophenyl compounds
Adenosine receptor antagonists
Antiparkinsonian agents
Experimental drugs
Monoamine oxidase inhibitors
Xanthines | 3-Chlorostyrylcaffeine | [
"Chemistry"
] | 315 | [
"Pharmacology",
"Xanthines",
"Medicinal chemistry stubs",
"Alkaloids by chemical classification",
"Pharmacology stubs"
] |
77,954,652 | https://en.wikipedia.org/wiki/MSX-4 | MSX-4 is a selective adenosine A2A receptor antagonist used in scientific research. It is a water-soluble amino acid ester prodrug of MSX-2, the active metabolite of the drug. MSX-4 reverses the motivational deficits induced by the dopamine D2 receptor antagonist eticlopride in animals and hence has the capacity to produce pro-motivational effects. MSX-4 was first described in the scientific literature by 2008.
See also
Istradefylline
MSX-3
References
3-Methoxyphenyl compounds
Adenosine receptor antagonists
Amino acids
Esters
Experimental drugs
Pro-motivational agents
Prodrugs
Propargyl compounds
Xanthines | MSX-4 | [
"Chemistry"
] | 155 | [
"Pharmacology",
"Biomolecules by chemical classification",
"Esters",
"Xanthines",
"Functional groups",
"Prodrugs",
"Chemicals in medicine",
"Medicinal chemistry stubs",
"Amino acids",
"Organic compounds",
"Alkaloids by chemical classification",
"Pharmacology stubs"
] |
77,955,200 | https://en.wikipedia.org/wiki/MSX-2 | MSX-2 is a selective adenosine A2A receptor antagonist used in scientific research. It is a xanthine and a derivative of the non-selective adenosine receptor antagonist caffeine.
The affinities (Ki) of MSX-2 for the human adenosine receptors are 5.38 to 14.5nM for the adenosine A2A receptor, 2,500nM for the adenosine A1 receptor (172- to 465-fold lower than for the A2A receptor), and >10,000nM for the adenosine A2B and A3 receptors (>690-fold lower than for the A2A receptor).
MSX-2 has poor water solubility, which has limited the use of MSX-2 itself. Water-soluble ester prodrugs of MSX-2, including MSX-3 (a phosphate ester prodrug) and MSX-4 (an amino acid ester prodrug), have been developed and used in place of MSX-2. MSX-3 is best-suited for use by intravenous administration, whereas MSX-4 can be administered by oral administration.
MSX-3 and MSX-4 reverse motivational deficits in animals and hence have the capacity to produce pro-motivational effects.
MSX-2 and MSX-3 were first described in the scientific literature by 1998. Subsequently, MSX-4 was developed and described by 2008.
See also
3-Chlorostyrylcaffeine
Istradefylline
Preladenant
References
3-Methoxyphenyl compounds
Adenosine receptor antagonists
Experimental drugs
Pro-motivational agents
Prodrugs
Propargyl compounds
Xanthines | MSX-2 | [
"Chemistry"
] | 370 | [
"Pharmacology",
"Xanthines",
"Medicinal chemistry stubs",
"Chemicals in medicine",
"Prodrugs",
"Alkaloids by chemical classification",
"Pharmacology stubs"
] |
77,955,402 | https://en.wikipedia.org/wiki/Lu%20AA41063 | Lu AA41063 is a selective adenosine A2A receptor antagonist. Structurally, it is a non-xanthine.
The affinities (Ki) of the drug for the human adenosine receptors are 5.9nM for the adenosine A2A receptor, 410nM for the adenosine A1 receptor (69-fold lower than for the A2A receptor), 260nM for the adenosine A2B receptor (44-fold lower than for the A2A receptor), and >10,000nM for the adenosine A3 receptor (>1,695-fold lower than for the A2A receptor).
Lu AA41063 was first described in the scientific literature by 2014.
Lu AA47070, a water-soluble phosphate ester prodrug of Lu AA41063, is orally active and was under development for the treatment of Parkinson's disease but was discontinued. In addition to its antiparkinsonian-like effects, Lu AA47070 reverses motivational deficits in animals and hence shows pro-motivational effects.
References
Abandoned drugs
Adenosine receptor antagonists
Anilides
Benzamides
Fluoroarenes
Pro-motivational agents
Thiazolidines | Lu AA41063 | [
"Chemistry"
] | 265 | [
"Pharmacology",
"Drug safety",
"Medicinal chemistry stubs",
"Pharmacology stubs",
"Abandoned drugs"
] |
77,955,627 | https://en.wikipedia.org/wiki/IRAS%2019254-7245 | IRAS 19254-7245, more commonly referred as the "Superantennae", are a pair of interacting galaxies located in the constellation of Pavo. It is located 820 million light years from Earth. It is an ultraluminous infrared galaxy and a Seyfert galaxy.
Characteristics
IRAS 19254-7245 is classified a galaxy merger. It is made up of two giant gas-rich spiral galaxies with a projected separation of ~ 2 kpc. With a disturbed morphology, the galaxy contains two tidal tails found stretching outwards to a total extend of 350 kiloparsecs (kpc). It is said to represent the nearby galaxy pair, NGC 4038/4039 known as the Antennae Galaxies hence its namesake. However the object is ~ 5 times larger and ~ 10 times more luminous than the pair thus being called the "Superantennae".
The Superantennae also has total molecular gas detection of MH2 = 3.0 x 1010 Msun. It is optically an Seyfert type II galaxy according to Mirabel and colleagues. ISO mid-infrared spectroscopy did detect a presence of an active galactic nucleus, although there is no clear indications of a dominated energy source.
Double nucleus
The two galaxies in the Superantennae system each have a distinctive nucleus. The northern nucleus appears in a post star formation stage but however less luminous when seen in infrared rays. It shows dynamical components like a broad-line component measuring ~ 2000–2500 km s−1 at full width at half maximum (FWHM) connected with the other nucleus, within the galaxy's inner arcmin. Not to mention, the northern nucleus contains high-velocity clouds and narrow components (FWHM < 500 km s−1) associated with its procreator discs.
The southern nucleus of the Superantennae is active when studied at multiple wavelengths. According to observations made by Berta, it shows spectrophotometric characteristics in agreement with young and old stellar populations in the southern nucleus. The two types constitutes ~ 35 and ~ 65 of the mass of the southern galaxy respectively.
Further observations are made on the two nuclei of the Superantennae by Chandra X-ray Observatory. The northern nucleus shows absence of AGN activity. On the other hand, the AGN of the southern nucleus is embedded and is Compton-thick. It has an absorbing column density higher than 1024 cm−2. Furthermore, the southern nucleus has a candidate X-ray source located 8" south of it. The off-point source is found to have a 0.3-10 keV luminosity of ~ 6 x 1040 ergs−1 and is connected with the Superantennae.
Presence of maser emission
The Superantennae is known to show megamaser emission. According to Atacama Large Millimeter Array, an extremely luminous emission line of (6 x 104 LΘ) 183 GHz H2O 31,3 - 22,0. This is interpreted as H2O emission originating in the maser amplification inside warm and dense molecular gas based on its compact nature (≥200 parsecs).
References
IRAS catalogue objects
Galaxy mergers
Luminous infrared galaxies
Pavo (constellation)
084913
Seyfert galaxies
Starburst galaxies | IRAS 19254-7245 | [
"Astronomy"
] | 674 | [
"Constellations",
"Pavo (constellation)"
] |
77,956,259 | https://en.wikipedia.org/wiki/IC%201481 | IC 1481 is a spiral galaxy located in the Pisces constellation. It is located 289 million light years from Earth and was discovered by Austrian astronomer, Rudolf Spitaler on October 6, 1891. The galaxy has an approximate diameter of 65,000 light years with a surface brightness of 12.8 square arcmin.
According to an optical image, IC 1481 has an Sb morphological classification. The galaxy also contains an active galactic nucleus (AGN). It is classified as a LINER galaxy. showing an extensive narrow-line region. The region of IC 1481 has bright portions forming in a figure eight pattern and extends at Position Angle (PA) = 50° by ~ 13 arcseconds on both sides of its nucleus. It also show emission knots towards the field edges. The stellar population of IC 1481 shows a post-starburst signature, which the Balmer lines contain strong absorption.
A luminous H2O maser emission is found towards IC 1481. The spectrum of the maser has a narrow and strong feature of 0.15 Jy and FWHM = 2 km s−1. It is also weak and broad. With an isotropic luminosity of L = 320 LΘ, this suggests a megamaser.
The maser features are found distributed, which they contain a velocity gradient. This suggests the AGN of IC 1481 has an unstable molecular gas disk with a mass of (4.3 ± 0.3) x 107 MΘ. The disk is seen edge-on. It has a thickness of 2H = 1.5-4.2 pc and a radius of r = 2.8-14.0 pc making the largest amongst other maser disks observed in other AGNs. Not to mention, the disk has a rotation of Vrot = 124–168 km s−1 and a velocity dispersion measured by △V ≈ 31 km s−1. Further observations found the disk of IC 1481 is huge indicated by its rotation curve being a sub-Keplerian. When compared to the galaxy's black hole mass of <107 MΘ, its mass is higher.
One supernova has been observed in IC 1481: SN2000ey (typeIa, mag. 16.2).
References
1481
Spiral galaxies
Active galaxies
Pisces (constellation)
12505
071070
18911006
23168+0537 | IC 1481 | [
"Astronomy"
] | 491 | [
"Pisces (constellation)",
"Constellations"
] |
77,956,445 | https://en.wikipedia.org/wiki/Thuchomyces | Thuchomyces (sometimes mistakenly called “Thucomyces”) is a genus of Archean fossils from the Witwatersrand of South Africa, and is the earliest macroscopic land life known. The generic name derives from thucholite, the carbonaceous material which Thuchomyces is preserved in, and the Ancient Greek word "myces", meaning "fungus". The specific name, lichenoides, derives from its similarity to some modern lichens.
Description
Thuchomyces resembles modern columnar biomats, alongside certain lichens, however the latter are far more recent, only having appeared at most 300 million years ago, and therefore it almost certainly is not a lichen, or even a eukaryote at all. Some fossils have a round structure at their tip, interpreted as a diaspore, and these structures can also be observed in the rock surrounding the fossils. The internal structure of Thuchomyces consists of a network of hyphae, made of intensely branching cells possibly connected via anastomoses. The outer layer of the organism consists of highly agglutinated hyphae with a layer of loose tissue inside it, alongside a "central cord" observed in immature specimens which disappears with age. Thuchomyces columns are roughly 200–500 micrometers across, and reach a height of roughly 1 mm. Thuchomyces shares many similarities with the Paleoproterozoic Diskagma, having a similar size and shape, alongside both forming dense palisades on paleosols. However it lacks the spines of Diskagma and has complex vertical partitions, alongside having rounded terminations instead of the cup-like tips of Diskagma.
Paleoecology
Taking into account various features such as ventifacts, the concentration of carbon-13 in the rock and other geological features, the sediments Thuchomyces is known from are interpreted as being a wind-blasted desert environment crossed by ephemeral streams, which was occasionally flooded. In addition another organism named Witwateromyces conidiophorus, a possible actinomycete bacterium, was found associated with Thuchomyces, possibly as a decomposer.
References
Archean life
Fossil taxa described in 1977
Prehistoric life genera
Incertae sedis | Thuchomyces | [
"Biology"
] | 473 | [
"Incertae sedis",
"Taxonomy (biology)"
] |
77,956,612 | https://en.wikipedia.org/wiki/Harry%20Medforth%20Dawson | Harry Medforth Dawson (11 November 1875 – 9 March 1939) was a professor of physical chemistry at the University of Leeds. He studied chemical kinetics, reaction mechanisms involving complex ions and their equilibria. He was elected Fellow of the Royal Society in 1933.
Dawson was born in Bramley. He studied at Leeds Modern School and went to Yorkshire College with a Baines Scholarship. Under Arthurs Smithells he became interested in chemistry. After graduating in 1896 with a BSc he obtained the 1851 Exhibition and went to Germany to study at Berlin, Giessen and Leipzig where he studied under Jacobus Henricus van't Hoff, Karl Elbs and Richard Abegg. After receiving his doctorate from the University of Giessen he returned to England in 1899 and joined Yorkshire College as a demonstrator. In 1905 he became a lecturer and received a DSc in 1907. In 1920 he became chair of physical chemistry and worked until his retirement. Dawson worked on iodination of ketones and examined the nature of acid catalysis.
Dawson married was Phillis Mary Barr in 1907 and they had three sons and two daughters.
References
1875 births
1939 deaths
English chemists
Academics of the University of Leeds
Physical chemists
People from Bramley, Leeds
Alumni of the University of Leeds | Harry Medforth Dawson | [
"Chemistry"
] | 261 | [
"Physical chemists"
] |
77,957,490 | https://en.wikipedia.org/wiki/ST%20Cephei | ST Cephei (ST Cep) is a large variable star located in the constellation Cepheus. It has a mean apparent magnitude of +7.84, and a solar radius of 1,218.
Distance
ST Cephei is very far from the solar system, and its parallax was not measured by the Hipparcos satellite. Its membership in the Cepheus OB2-B stellar association allows its distance to be estimated at 830 parsecs, or 2,715 light years.
Characteristics
ST Cephei is a red supergiant of spectral type M3I—previously cataloged as M2I—with an effective temperature of 3,600 Kelvin. It is a large supergiant, with a diameter around 290 times larger than the diameter of the Sun; another study, however, reduces this figure to 175 solar radii. Considering an intermediate radius between both values, if it were in the place of the Sun, its surface would extend to the Earth's orbit. Despite this, its size is far from the two known hypergiants in this constellation, Me Cephei and VV Cephei.
The bolometric luminosity of ST Cephei is 8,400 times greater than that of the Sun. It has a mass 9 times greater than the Sun, at the limit from which stars end their lives by exploding as supernovae. Like other analogous supergiants, it loses mass; Its loss of stellar mass—in the form of dust, since the atomic and molecular gas could not be evaluated—is quantified at 2.5 × 10-9 solar masses per year.
In 1910 it was announced that Evelyn Leland had discovered that the star, then called BD +56°2793, is a variable star. That same year it was given its variable star designation, ST Cephei.
Listed as an LC irregular variable star, the brightness of ST Cephei varies by about two magnitudes, with no period recognized.
See also
List of largest stars
List of variable stars
MY Cephei
References
Variable stars
Cephei, ST
Cepheus (constellation)
Supergiants | ST Cephei | [
"Astronomy"
] | 440 | [
"Constellations",
"Cepheus (constellation)"
] |
74,957,988 | https://en.wikipedia.org/wiki/Pocket%20forest | A pocket forest is created by planting native trees and shrubs in close proximity as a means of rapidly restoring native plant species in damaged ecosystems. While forests naturally grow through a primary stage and then a secondary stage before reaching their climax stage, pocket forests are created by a dense planting of climax stage species which grow rapidly in competition for sunlight.
Pocket forests have been embraced by environmentalists as a means of reforesting urban spaces and teaching urban residents about native forest environments. The growing interest in pocket forests was inspired in large part by the work of Japanese botanist Akira Miyawaki, whose "Miyawaki forests" have influenced the development of a variety of pocket forest methodologies adapted to different climates and spacial constraints.
Methods
A variety of protocols for site preparation and planting have been developed, all sharing the same underlying principles as the Miyawaki method. The following is an example methodology:
The area to be planted is first covered with a layer of cardboard which is then covered with of compost and allowed to acclimate to local moisture conditions for several months. The covered area is then planted with year-old plant nursery saplings spaced approximately apart. The entire surface area should be planted at the same time with a variety of native species so no saplings of the same species are adjacent to each other. Watering is unnecessary for native plants acclimated to the local environment; although watering for the first few years after planting, and during drought periods, will reduce mortality of individual plants. Pocket forests planted with greater density than commercial timberland utilize edge lighting in addition to overhead lighting to grow faster while absorbing more carbon dioxide per acre.
Three is the minimum number of different species of nursery saplings for planting a pocket forest. The arrangement below of species A, B and C illustrates avoidance of planting the same species in adjacent positions.
A B C A
B C A B C
A B C A
Examples
Pocket Forests CLG assists creation of pocket forests of within urban areas of Ireland.
The Yakama Nation has planted seven pocket forests of 47 species totaling on their corrections and rehabilitation facility.
A Miyawaki forest has been planted over a landfill in Cambridge, Massachusetts, as part of Danehy Park.
A forest has been planted as part of Griffith Park in Los Angeles.
Several Miyawaki forests have been planted in Berkeley, California.
A pocket forest of 20 species is being planted in the City of Brussels.
The town of Ayer, Massachusetts, organized community volunteers to plant a pocket forest.
Potential problems
Miyawaki developed the method as a means of replenishing forest soils by allowing dead leaves and twigs to decompose in a moist, wood-rotting ecosystem. This process may be less successful in drier fire ecosystems where nutrients are recycled as ashes. The dense pocket forest forms a capture mechanism for wind-blown embers, dried ground litter is an ignition source, and the multi-layered pocket forest forms a fuel ladder with wildfire risks in urban areas.
Image Gallery
References
Further reading
Forests
Habitats
Trees
Ecosystems | Pocket forest | [
"Biology"
] | 610 | [
"Forests",
"Symbiosis",
"Ecosystems"
] |
74,959,009 | https://en.wikipedia.org/wiki/Xiaoming%20Liu | Xiaoming Liu is a Chinese-American computer scientist and an academic. He is a Professor in the Department of Computer Science and Engineering, MSU Foundation Professor as well as Anil K. and Nandita Jain Endowed Professor of Engineering at Michigan State University.
Liu is most known for his works in the fields of computer vision, machine learning, and biometrics, with a particular focus on facial analysis and three-dimensional (3D) vision. Moreover, he is the recipient of the 2018 and 2023 Withrow Distinguished Scholar Award from the Michigan State University College of Engineering.
Liu is a fellow of the International Association for Pattern Recognition (IAPR) and The Institute of Electrical and Electronics Engineers (IEEE). Additionally, he is the Associate Editor of the journal IEEE Transactions on Pattern Analysis and Machine Intelligence.
Education
Liu completed his Bachelor of Arts degree in Computer Science and Engineering from Beijing Information Technology Institute in 1997. In 2000, he obtained a Master of Science degree in Computer Science and Engineering from Zhejiang University under the supervision of Yueting Zhuang. This was followed by a Ph.D. in Electrical and Computer Engineering, supervised by Tsuhan Chen and Vijayakumar Bhagavatula from Carnegie Mellon University in 2004.
Career
Liu began his academic career in 1998 by joining the Intelligent CAD Lab at Zhejiang University as a research assistant and served until 1999. Between 2000 and 2004, he worked at the Advanced Multimedia Processing Lab at Carnegie Mellon University as a research assistant. In 2012, Liu joined Michigan State University, where he assumed various academic roles over the years. He began as an assistant professor in the Department of Computer Science and Engineering, a position he held from 2012 to 2018, and subsequently became an associate professor in the same department from 2018 to 2020. Since 2020, he has been serving as a professor in the Department of Computer Science and Engineering at Michigan State University. Additionally, he holds appointments as an MSU Foundation Professor since 2021 and as the Anil K. and Nandita Jain Endowed Professor of Engineering at Michigan State University since 2022.
From 2004 to 2012, Liu worked as a Computer Scientist at the Visualization & Computer Vision Lab at GE Global Research. Since 2021, he has held the role of Visiting Researcher Scientist as part of Google's Visiting Researcher Program. He has also been serving as an Associate Editor for the Journal IEEE Transactions on Pattern Analysis and Machine Intelligence since 2023. He has served as Associate Editor for the journal of Neurocomputing, Pattern Recognition Letters, Pattern Recognition, and IEEE Transaction on Image Processing.
Research
With an h-index of 71 and a citation count of 23,105, he has authored over 200 publications spanning the field of computer vision, with a primary focus on recognition, modeling, and 3D perception.
Recognition
The recognition and analysis of human facial images have been a central focus in the field of computer vision since its inception. Liu's recognition research has focused on fundamental problems such as designing effective loss functions for face matcher learning, integrating identity information across frames, exploring the link between image restoration and recognition in low-quality imagery, and investigating the role of 2D and 3D shapes in recognition. His group designed a margin-based loss function that is adaptive to the diverse image quality in face recognition training dataset, which resulted in a generic face matcher called Adaface. Concentrating his research efforts on tackling video-based face recognition, his study underscored the contribution of temporal dynamics in recognition and introduced an adaptable method called "CAFace" for understanding the connections between identity details across video frames and executing sequential recognition while streaming video.
One of the primary research objectives of Liu's recognition research is to cultivate trust between AI systems and their users. He led research in face presentation attack detection (PAD) and published papers. He created algorithms to mitigate bias in facial recognition by revealing that different demographic groups require distinct convolutional neural network (CNN) kernels, leading to an adaptive architecture that enhances accuracy while reducing bias. Moreover, he proposed a technique Model Parsing for reverse engineering GMs to understand their hyperparameters. His group also developed passive and proactive approaches to deep fake detection and localization.
Modeling
Liu's modeling research has centered on image alignment and intrinsic image decomposition. He developed Boosted Appearance Model, a discriminative model for image alignment that uses a boosting-based classifier to distinguish between correctly aligned images with ground-truth landmarks and incorrectly aligned images with perturbed landmarks. Additionally, to address the limitations of BAM, he introduced BRM, which focused on learning a score function that is concave in the vicinity of the correct alignment, potentially improving alignment accuracy. Furthermore, he identified the challenge of aligning profile-view faces accurately and addressed this by developing approaches that treat image alignment as a 3D Morphable Models (3DMM) fitting problem, enabling the estimation of 3D facial landmarks.
Liu's intrinsic image decomposition research addressed the problem of 3D reconstruction from 2D images, aiming to estimate high-fidelity 3D surface information of objects or scenes. He proposed an approach based on intrinsic image decomposition, breaking down an image into four components: camera projection matrix, shape parameters, albedo parameters, and illumination parameters, achieved through an encoder. Notably, the absence of ground truth labels for training the encoder leads them to employ two decoders, one for generating 3D shape and another for albedo maps. He used a differentiable renderer to jointly learn the encoder and decoders, ensuring that the rendered image closely matches the original input. Initially developed for faces, this framework serves as a deformable appearance and shape model, akin to the conventional 3D Morphable Model (3DMM) but capable of learning directly from 2D in-the-wild images without the need for 3D scans. Moreover, it was extended to generic objects through the development of implicit functions.
3D perception
Liu's 3D vision research has explored the fields of 3D object detection and multi-sensor fusion. He proposed a method, referred to as M3D-RPN (Monocular 3D Region Proposal Network) which enhanced the effectiveness of monocular 3D object detection and Bird's Eye View tasks when applied to the KITTI urban autonomous driving dataset. This research was further extended in the direction of video-based detection, the creation of depth equivariant networks and non-maximum suppression (NMS) techniques. Moreover, he specialized in the field of multi-sensor fusion, focusing on integrating cameras with LiDAR or Radar sensors to enhance 3D perception capabilities. His work encompassed tasks like depth completion, velocity estimation, and 3D object detection.
Awards and honors
2018 – Withrow Distinguished Scholar–Junior Award
2020 – Fellow, International Association for Pattern Recognition
2021 – MSU Foundation Professor, Michigan State University
2022 – Fellow, Institute of Electrical and Electronics Engineers
2022 – Anil K. and Nandita Jain Endowed Professor of Engineering, Michigan State University
2023 – Withrow Distinguished Scholar–Senior Award
Selected articles
Zhu, X., Lei, Z., Liu, X., Shi, H., & Li, S. Z. (2016). Face alignment across large poses: A 3D solution. In Proceedings of the IEEE conference on computer vision and pattern recognition (pp. 146–155).
Tai, Y., Yang, J., & Liu, X. (2017). Image super-resolution via deep recursive residual network. In Proceedings of the IEEE conference on computer vision and pattern recognition (pp. 3147–3155).
Tai, Y., Yang, J., Liu, X., & Xu, C. (2017). MemNnet: A persistent memory network for image restoration. In Proceedings of the IEEE international conference on computer vision (pp. 4539–4547).
Tran, L., Yin, X., & Liu, X. (2017). Disentangled representation learning GAN for pose-invariant face recognition. In Proceedings of the IEEE conference on computer vision and pattern recognition (pp. 1415–1424)
Liu, Y., Jourabloo, A., & Liu, X. (2018). Learning deep models for face anti-spoofing: Binary or auxiliary supervision. In Proceedings of the IEEE conference on computer vision and pattern recognition (pp. 389–398).
References
Computer scientists
Zhejiang University alumni
Carnegie Mellon University alumni
Michigan State University faculty
21st-century American scientists
Living people
Year of birth missing (living people) | Xiaoming Liu | [
"Technology"
] | 1,734 | [
"Computer science",
"Computer scientists"
] |
74,960,351 | https://en.wikipedia.org/wiki/Arturo%20A.%20Keller | Arturo A. Keller is a civil and environmental engineer and an academic. He is a professor at the Bren School of Environmental Science & Management at the University of California, Santa Barbara.
Keller is most known for his work on water quality and resource management, primarily focusing on emerging contaminants as well as creating technologies and management strategies to address water pollution. His work is highly cited, with over 23,300 citations. He is the recipient of the 2015 Agilent Thought Leadership award for his contributions towards the contemporary understanding of the potential environmental implications of nanotechnology, with a specific focus on its impact within agricultural systems.
Education
Keller obtained a B.S. in Chemical Engineering and B.A. in Chemistry from Cornell University in 1980. In 1992, he completed his M.S. in Civil (Environmental) Engineering, followed by a PhD in Civil (Environmental) Engineering in 1996 from Stanford University.
Career
Keller started his academic career in 1996 by joining the University of California, Santa Barbara. There he held multiple appointments including serving as an assistant professor at the Bren School of Environmental Science and Management from 1992 to 1996, and associate professor from 2002 to 2006. Since 2006, he has been a professor. In 2023, he was promoted to the rank of Distinguished professor.
From 1992 to 1996, Keller worked as a Research Associate in the Environmental Division at the Electric Power Research Institute (EPRI). He co-directed the UC Center on the Environmental Implications of Nanotechnology, from 2008 to 2020. He also co-directed the USEPA-funded Chemical Life Cycle Collaborative between 2014 and 2019, where the team developed a framework to predict early life-cycle impacts of new chemicals based on molecular structure, applications, and use characteristics.
Research
Keller has contributed to the management of the Santa Ana River basin and the establishment of a nutrient trading program for the Ohio River Basin, which earned him recognition through a 2015 US Water Prize. His group received a grant from USEPA and developed a framework employing artificial intelligence, specifically machine learning, alongside other predictive techniques for expeditiously conducting risk assessments for both novel and pre-existing chemicals. He also developed the first numerical model, ChemFate, capable of accommodating diverse chemical classes within one unified framework. He has authored numerous publications spanning the fields of water quality and resource management, environmental engineering, the fate and toxicity of nanomaterials as well as their effects on crops.
Environmental science and engineering
Keller's environmental sciences research has focused on developing methods for quantifying nanomaterial use and release, both at the global and regional levels. His collaborative work with Suzanne McFerran and others provided a global assessment of likely engineered nanomaterials (ENM) emissions into the environment and landfills, revealing their dominant types, applications, and estimated distribution in various environmental compartments. In his estimation of the ENM concentrations at global, regional, national, and local levels, he used a life-cycle approach and material flow analysis, to assess ENM concentrations at different environmental scales, including examples like the San Francisco Bay area, addressing their relevance for industry, regulators, and toxicologists. In his 2014 study, alongside Anastasiya Lazareva, he estimated ENM release from different uses, in particular personal care products, developed an environmental release model for ENMs in major cities, highlighting local factors' influence on release, and found that ENM concentrations across cities would vary significantly, due to local conditions that control the fate of ENMs. In 2023, his team evaluated the potential implications of nanotechnology from 2020 to 2030, and found that there is a projected rapid pace of introduction of novel nanomaterials in applications such as renewable energy generation and storage, but that personal care products continue to represent the most significant release to the environment. Some of his current work is investigating the life cycle of these materials as they are processed in water treatment facilities, and accumulate in bio-solids.
In collaboration with Peng Wang, Keller and his team have developed a novel class of magnetic nanomaterials, Mag-PCMAs, that can be used to treat water with a wide range of contaminants, including many organic pollutants, oxyanions such as perchlorate, and metals. Very recently, he and Qian Gao demonstrated the use of these novel nanoparticles for water disinfection, to remove pathogens while being able to reuse the disinfectant, thereby reducing cost and environmental impacts. Key to the eventual use of nanotechnology for water treatment will be its effectiveness and cost-competitiveness, which was assessed by Keller, Adeyemi Adeleye and other colleagues. With these concepts in mind, he and Victoria Broje developed an advanced oil skimmer for collecting oil from seawater after an oil spill.
Fate and toxicity of different classes of nanomaterials
Keller has focused on the fate and toxicity of different classes of nanomaterials. His collaborative work with Hongtao Wang and others explored the conditions that increase or decrease the likelihood of exposure to ENMs, particularly in the aquatic environment. Studies of the behavior of well known ENMs, such as Titanium Dioxide (TiO2), Zinc Oxide (ZnO), and Cerium Dioxide (CeO2), within aqueous matrices commonly encountered in realistic environmental settings such as freshwater, groundwater, estuarine and marine waters, demonstrated the major influence of water characteristics such as pH, natural organic matter, and ionic strength (water hardness and salinity). Furthermore, working with Adeyemi Adeleye and others, they demonstrated that microscopic organisms such as phytoplankton and microbes can release extracellular polymeric substances, that play a key role in the determining how ENMs will behave in natural waters. Other studies showed that ENMs are very likely to form aggregates with natural sediments in water, and in fact this can be used as a "cleansing" mechanism to remove ENMs from contaminated water, by adding clay particles to remove them. In 2014, he and his colleague Kendra Garner performed an analysis of publications, to develop the emerging patterns for ENMs in the environment, assessing the potential exposure and toxicity of the most widely used ENMs, and ranking them from high to low risk. These studies led to the development of the nanoFate model, which can be used to assess the predicted environmental concentrations of ENMs in different regions, under a variety of conditions, and considers the dynamics of ENM release as well as local climate and hydrology. Keller has also worked closely with ecotoxicologists, to investigate the health effects of ENMs on different aquatic organisms, such as marine phytoplankton, sea urchins, daphnids, and mussels. These studies have demonstrated that some ENMs pose a health risk to diverse organisms at higher concentrations, typically above predicted environmental concentrations. For example, TiO2 nanoparticles are phototoxic to marine phytoplankton, while ZnO nanoparticles notably inhibited their growth. Mussels are filter feeders, and can thus remove large number of particles from water, including ENMs, which can result in transfer of ENMs up the food chain. Eventually, the results of several toxicity studies on a wide range of aquatic species was assessed using Species Sensitivity Distributions for nanomaterials, a tool developed by USEPA to better assess the potential impact of toxicants on an ecosystem.
Effects of nanomaterials on crops
Keller, in his research, has recently turned his attention to the benefits and potential negative implications of ENMs on agricultural crops. Copper-based nanopesticides promise high effectiveness against fungi and other crop pests, while potentially reducing the amount applied. This may result in less cost for the farmer, and lower environmental implications. Working with Yiming Su and colleagues, they demonstrated that for nanotechnology to live up to its promise, costs have to continue to decrease, while effectiveness requires a careful assessment of the form in which the nanopesticides are formulated. In collaboration with Lijuan Zhao and others, the benefits of nanotechnology to reduce plant stress were assessed. To evaluate the effect of ENMs on crop plants, his research group have been researching the use of metabolomics, to assess how plants respond to the use of different ENMs. His metabolomics analysis with Lijuan Zhao and others highlighted the potential implications and detoxification strategies associated with the agricultural use of nano-Cu and demonstrated that exposure to copper nanoparticles (nano-Cu) in hydroponic culture significantly alters nutrient uptake, triggers metabolic changes, and activates defense mechanisms in cucumber plants. In his investigation of the interaction between Cu(OH)2 nano pesticides and lettuce plants, his study provided insights into the molecular-scale plant response to copper nano pesticides in agriculture, and revealed that exposure of lettuce plants to Cu(OH)2 nano pesticides predominantly accumulated copper in leaves, disrupted metabolism, caused oxidative stress, and triggered detoxification. Furthermore, a study suggested that Cu-containing nano pesticides, while not harming photosynthesis in cucumber plants, induce molecular responses related to antioxidant and detoxification genes, potentially serving as biomarkers for nano pesticide exposure. In related research, his exploration of the metabolic effects of Cu(OH)2 nano pesticide and copper ions on spinach leaves revealed reductions in antioxidants, disruption of metabolic pathways, and a potential decrease in nutritional value.
Water quality and resource management
At the larger scale, Keller has developed the science for large-scale water quality trading programs. For trading to be effective, knowledge of the factors that go into evaluating a trade was developed by Keller and his team. This work led to the 2015 United States Water Prize from the U.S. Water Alliance to the team led by Jessica Fox at the Electric Power Research Institute. Keller and Hongtao Wang, along with other collaborators, have also made contributions to the assessment of the Energy-Water Nexus, that is the linkage between these two key resources. His research highlighted many important aspects, including the fact that significant energy is needed for potable water treatment, as well as for wastewater processing. His research further emphasized that the water footprint of the iron and steel industry is also significant, with important implications for China and other major economies. Additionally, his research also stressed that water is also an important aspect in power generation, which is changing as the use of renewable energies continues to rise.
Awards and honors
2015 – Agilent Thought Leadership Award, Agilent Technologies
2015 – United States Water Prize, U.S. Water Alliance
Selected articles
Keller, A. A., Wang, H., Zhou, D., Lenihan, H. S., Cherr, G., Cardinale, B. J., ... & Ji, Z. (2010). Stability and aggregation of metal oxide nanoparticles in natural aqueous matrices. Environmental science & technology, 44(6), 1962–1967.
Keller, A. A., McFerran, S., Lazareva, A., & Suh, S. (2013). Global life cycle releases of engineered nanomaterials. Journal of nanoparticle research, 15, 1–17.
Keller, A. A., & Lazareva, A. (2014). Predicted releases of engineered nanomaterials: from global to regional to local. Environmental Science & Technology Letters, 1(1), 65–70.
Adeleye, A. S., Conway, J. R., Garner, K., Huang, Y., Su, Y., & Keller, A. A. (2016). Engineered nanomaterials for water treatment and remediation: Costs, benefits, and applicability. Chemical Engineering Journal, 286, 640–662.
Miller, R. J., Lenihan, H. S., Muller, E. B., Tseng, N., Hanna, S. K., & Keller, A. A. (2010). Impacts of metal oxide nanoparticles on marine phytoplankton. Environmental science & technology, 44(19), 7329–7334.
References
American civil engineers
Environmental engineers
Cornell University alumni
Stanford University alumni
University of California, Santa Barbara faculty
21st-century American engineers
20th-century American engineers
Living people
Year of birth missing (living people) | Arturo A. Keller | [
"Chemistry",
"Engineering"
] | 2,567 | [
"Environmental engineers",
"Environmental engineering"
] |
74,960,592 | https://en.wikipedia.org/wiki/Commation | Commation is a genus of marine heterotrophic protists closely related to the actinophryids. It contains two species, Commation cryoporinum and Commation eposianum, discovered in antarctic waters and described in 1993. Currently, the genus is classified within a monotypic family Commatiidae and order Commatiida. Along with the photosynthetic raphidophytes, these organisms compose the class of stramenopiles known as Raphidomonadea.
Etymology
The name of the genus, Commation, derives , referring to the overall comma shape of the biconvex cells.
Morphology
Commation is a genus of unicellular eukaryotes. They are solitary planktonic organisms that live as circular or oval, sometimes flattened, cells with a proboscis. Occasionally, a single flagellum with tripartite hairs (or mastigonemes) emerges from the proximity of the proboscis. They predominantly move by gliding, a motion facilitated by excretion of mucus. The cell nucleus appears at the base of the proboscis. The presence of two flagellar basal bodies hints at their stramenopile origin, since two heterokont flagella (one smooth, one with mastigonemes) are the main distinguishing trait of the Stramenopiles. They also present microtubular roots and a striated root or rhizoplast, a fiber connecting the nucleus to the basal bodies.
The mitochondria of Commation species have tubular cristae. One or more types of extrusomes occur scattered throughout the cytoplasm. One species, C. cryoporinum, presents two types of extrusomes, some of them visible under light microscopy when large enough. The other species, C. eposianum, only contains one type of extrusome that is not visible. The complex cytoskeleton of Commation contains structures consisting of microtubular arrays and electron-dense structures, present in both the cell bodies and proboscis.
Ecology
Commation cells are phagotrophic and non-photosynthetic, unlike their raphidophyte relatives. They live as plankton on the Antarctic Ocean, and were obtained at a depth of 10–20 meters. A single cell similar to C.eposianum was found in a cover slip preparation belonging to a 1989 sample obtained from a Pacific Ocean cruise off California, indicating that the genus Commation may not be endemic to the Antarctic region. Despite being heterotrophic, they are classified as part of the phytoplankton in ecological surveys.
Systematics
Commation was described as a genus by two biologists of the University of Copenhagen, Helge Abildhauge Thomsen and Jacob Larsen. The description was published in 1993 on the European Journal of Protistology. Subsequent taxonomic research papers assigned Commation to a monotypic family Commatiidae and order Commatiida. The order Commatiida was initially assigned to the class Jacobea on the basis of branched tubular mitochondrial cristae. Phylogenetic analyses in 2013 demonstrated that both Commation and a group of heliozoa known as Actinophryida were related to the raphidophyte algae. The first two groups, while heterotrophic, were united in the subclass Raphopoda, while the raphidophyte algae were given their own subclass Raphidophycidae. Together, these two subclasses currently compose the class Raphidomonadea.
Species
Two species have been described:
Commation cryoporinum
Commation eposianum
References
Taxa described in 1993
Ochrophyte genera
Ochrophyta | Commation | [
"Biology"
] | 769 | [
"Ochrophyta",
"Algae"
] |
74,960,648 | https://en.wikipedia.org/wiki/Polux | Polux is a measuring device for checking the condition of wooden electricity and telephone poles. This is a specific non-destructive testing tool for wooden poles.
Description
Polux technology is used for safety and maintenance diagnostics. The measurements enable operators to climb poles safely and check the condition of the wood to estimate its remaining lifespan.
History
The Polux technology was developed in the early 90s by Professor Jean-Luc Sandoz, following on from the Sylvatest, at the initial request of EDF, which had the dual problem of the safety and lifespan of their poles. In 2003, the technology was presented at the 17th International Congress on Electrical Distribution Networks in Barcelona. In 2017, a report by Orange's CGT insisted on the danger of unmaintained poles and demonstrated, through several large-scale comparative tests, the scientific contribution of Polux technology to increasing the safety of personnel climbing poles, drawing on the experience of Enedis. It works with Picus software, which uses data consisting of local densitometry measurements at the ground line and hygroscopic measurements. The Polux technology continues to be developed at the CBS-Lifteam Research and Development Centre in Switzerland. The 5th version enables faster data collection and processing, with a miniaturised tool and the Picus application downloadable to smartphones. Polux technology is used in a number of countries, including the United States, Canada, European Union, Africa and Asia.
Awards
In 2003, The Wall Street Journal awarded the first prize for innovation to Polux technology.
In 2006, the 14th international symposium on non-destructive testing equipment presented advances in the technology.
In 2011, the International Seminar of Electrical Energy Distributors presented the use of Polux technology in Germany, using Deutsche Telekom as an example.
Bibliography
• (en) Flávio L. R. Vidor, Marçal Pires, Berenice A. Dedavid, Pedro D. B. Montani, and Adriano Gabiatti, « », Rapport scientifique, 2010;
• (br) M. A. O. Cruz1; M. Pires; B. A. Dedavid; F. L. R. Vidor; W. S. Oliveira; R. C.Abruzzi, « », revue scientifique,2010 (lire en ligne [PDF]).
References
External links
US website
Officiel website
Maintenance
Quality control
Product testing
Product certification
Materials science
Materials testing
Electrical test equipment | Polux | [
"Physics",
"Materials_science",
"Technology",
"Engineering"
] | 509 | [
"Applied and interdisciplinary physics",
"Electrical test equipment",
"Materials science",
"Measuring instruments",
"Nondestructive testing",
"Materials testing",
"nan",
"Mechanical engineering",
"Maintenance"
] |
74,961,473 | https://en.wikipedia.org/wiki/Transition%20metal%20sulfate%20complex | Transition metal sulfate complexes or sulfato complexes are coordination complexes with one or more sulfate ligands. Being the conjugate base of a strong acid (sulfuric acid), sulfate is not basic. It is more commonly a counterion in coordination chemistry, not a ligand.
Bonding modes
Sulfate binds to metals through one, two, three, or all four oxygen atoms.
Among the handful of complexes containing sulfate (or sulfato) ligands, most examples feature unidentate or chelating bidentate sulfate. Well characterized xamples are found with cobalt(III) ammines since these complexes are exchange inert. Monodentate sulfate is found in [Co(tren)(NH3)(SO4)]+ (tren = tris(2-aminoethyl)amine) Although is unknown, forms instead (en = ethylenediamine). Bidentate sulfate is observed crystallographically in .
Sulfate function as a tridentate bridging ligand .
All four oxygen atoms of sulfate bond to metals in some Dawson-type polyoxometalates, e.g. [S2Mo18O62]4-.
Sulfate as a counterion
Tutton's salts, with the formula M'2M(SO4)2(H2O)6 (M' = K+, etc.; M = Fe2+, etc.), illustrate the ability of water to outcompete sulfate as a ligand for M2+. Similarly alums, such as chrome alum ([K(H2O)6][Cr(H2O)6][SO4]2), features with noncoordinated sulfate. In a related vein, some sulfato complexes confirmed by X-ray crystallography, convert to simple aquo complexes when dissolved in water. Copper(II) sulfate examplifies this behavior, sulfate is bonded to copper in the crystal but dissociates upon dissolution.
Synthesis
Sulfato complexes are commonly produced by reaction of metal sulfates with other ligands.
In some cases, sulfato complexes are produced from sulfur dioxide:
(PPh3 = triphenylphosphine)
Sulfato complexes also arise by air-oxidation of metal sulfides.
Reactions
A dominant reaction of sulfato complexes is solvolysis, i.e. displacement of sulfate from the first coordination sphere by polar solvents such as water.
Sulfato complexes are susceptible to protonation of uncoordinated oxygen atoms.
Further reading
Co(phen)2SO4
References
Ligands
Coordination chemistry
Sulfates | Transition metal sulfate complex | [
"Chemistry"
] | 542 | [
"Sulfates",
"Ligands",
"Coordination chemistry",
"Salts"
] |
74,961,679 | https://en.wikipedia.org/wiki/Commation%20cryoporinum | Commation cryoporinum is a species of heterotrophic protists discovered in 1993 in Antarctic waters. It is one of two species in the Commatiida, an order of stramenopiles closely related to actinophryids, a group of heliozoan protists, and to raphidophytes, a group of algae.
Etymology
The name of the species derives , a reference to the Herbst im Eis (meaning "Autumn in Ice") expedition which allowed the collection of this species. The name of the genus derives , which references the general biconvex shape of the cell.
Morphology
Commation cryoporinum is a species of unicellular eukaryotes composed of oval cells measuring 7–14 × 5–8 μm. They present a conspicuous proboscis measuring 9–14 μm in length and 2–4 μm in diameter at the base, relatively short and thick in comparison to the longer and thinner proboscis of Commation eposianum. Their complex cytoskeleton is dominated by microtubular components, not conspicuous under light microscopy. Two kinds of extrusomes can occur in both the cell body and the proboscis; the largest ones are visible under light microscopy, appearing as small refractile bodies. In contrast, C. eposianum only presents one type of extrusomes which is never visible under light microscopy.
References
Protists described in 1993
Ochrophyte species | Commation cryoporinum | [
"Biology"
] | 311 | [
"Ochrophyta",
"Algae"
] |
74,961,743 | https://en.wikipedia.org/wiki/Commation%20eposianum | Commation eposianum is a species of heterotrophic protists discovered in 1993 in Antarctic waters. It is one of two species in the Commatiida, an order of stramenopiles closely related to actinophryids, a group of heliozoan protists, and to raphidophytes, a group of algae.
Etymology
The name of the species, "eposianum" references the initiative behind the EPOS joint-European Antarctic research programme, which allowed this species to be discovered through an expedition to the Southern Ocean. The name of the genus derives , which references the general biconvex shape of the cell.
Morphology
Commation eposianum is a species of unicellular eukaryotes composed of spherical biconvex cells measuring 7–12 μm. They present a narrow proboscis measuring 16–18 μm in length, relatively long in comparison to the proboscis of Commation cryoporinum. Their cytoskeleton consists of a spiralling band composed of a microtubular sheet associated with 3 crystalline, electron-dense structures. This band occupies one half of the cell and gets thinner from the periphery towards the center of the cell. Other structural microtubules arise from the surface of the cell nucleus. The cell has only one type of extrusome which is not visible under light microscopy, in contrast to Commation cryoporinum which presents two types of extrusomes that can be visible if large enough.
References
Protists described in 1993
Ochrophyta
Ochrophyte species | Commation eposianum | [
"Biology"
] | 331 | [
"Ochrophyta",
"Algae"
] |
74,963,429 | https://en.wikipedia.org/wiki/South%20Carolina%20Aeronautics%20Commission | The South Carolina Aeronautics Commission (SCAC) is a government agency in the U.S. state of South Carolina. The SCAC, in conjunction with the Federal Aviation Administration, is "responsible for collecting, validating, and distributing the operational status of all aspects of the state’s air traffic facilities, in addition to the safety of the people in these locations." The agency also promulgates rules and regulations of airports and administers airport grants in the state.
The SCAC was created in 1935 by an act of the South Carolina General Assembly. Unlike most state aeronautics agencies in the Southeastern United States, the SCAC is not a part of the state's department of transportation.
References
Government of South Carolina
Aeronautics organizations
1935 establishments in South Carolina | South Carolina Aeronautics Commission | [
"Engineering"
] | 154 | [
"Aeronautics organizations"
] |
74,963,553 | https://en.wikipedia.org/wiki/Wisconsin%20Butter%20Fire | The Wisconsin butter fire, also known as the butter flood, great cheese fire, and great butter fire, was a fire and flood of processed meat and dairy that began on May 3, 1991, at a large storage facility in Madison, Wisconsin. The fire continued for eight days; there were no fatalities, but it caused millions of dollars in damages. The incident is known as the biggest commercial fire in Wisconsin state history and the Madison Fire Department's biggest and most expensive challenge.
Background
The fire occurred as America's butter surplus was near its peak, when the US government purchased excess quantities of government cheese and butter in efforts to keep prices stable. Due to the overzealous government purchasing, farmers increased production of milk and butterfat by 30 percent between 1974 and 1990 even though consumer demand was not increasing. A Wisconsin Daily State Journal article titled "The butter cup runneth over" from April 1990 reported that of dairy products were sitting in warehouses.
The fire and the flood
First flames
On May 3, 1991, flames broke out in the late afternoon at the Central Storage and Warehouse Company on Cottage Grove Road, a complex that stored of government surplus butter. At the time of the fire, the building also stored Ocean Spray cranberries and "millions and millions of hot dogs", according to an employee. Oscar Mayer stored of sausages in the facility. Building owner Ken Williams stated that the fire grew so quickly that "the sprinkler systems were not able to even work." According to a Wisconsin Department of Natural Resources report, the damages included bakery products, hams, and of anhydrous ammonia. It took about twenty hours to contain the blaze, and eight days until the fire was officially out.
A firefighter reported flames high. There were about twenty-five employees present at the factory, and none were injured.
Due to the thick, fatty pool of dairy, ladder trucks could not effectively enter and leave the area, nor could fuel trucks enter to refill the ladder trucks' gas tanks. Instead, mechanics traveled through the butter river on foot with buckets of diesel fuel. Spraying water at the building caused more gooey melted cheese and butter to flow out. Nearly 3,000 nearby Madison residents were evacuated on Friday night and moved to a high school because firefighters thought the flames might spread. The neighbors reported a horrible stench.
Butter flood
After about two and a half hours, the fire spread to a second factory building. Five hours later the building collapsed, creating a massive wave of melted butter. The fire threatened the facility's anhydrous ammonia tanks. "Once the walls caved in, [the butter] came out like a river", said fire lieutenant Berggren. City Engineering crews constructed levees to contain the dairy and lard.
Firefighters had to wade through viscous, slippery pools of butter and cheese that were high with deep ponds in some places. The melted dairy made it difficult to use typical equipment, so firefighters remained outside the building, trudging upstream through a hot flow. Firefighter Steven Davis reported having "butter in places a guy shouldn't have butter by the end of that night."
Cleanup and legacy
The Environmental Protection Agency states that butter spills have similar effects on wildlife to petroleum-based oil spills. The Wisconsin Department of Natural Resources worked to prevent the river of cream and cheese from clogging tubes and polluting local bodies of water. To contain the sludgy runoff of dairy, it constructed multiple dams to protect Starkweather Creek, which feeds into Lake Monona. City employees of Madison steered the butter river into a storm water discharge pond near the highway, but when the pond overflowed, some of its contents were pumped across the railroad tracks into another pond. The fire and subsequent dairy flood caused major financial losses, including $7.5 million in property damages , $70 million in contents , and nearly $1 million in fire control costs. The cleanup cost approximately $550,000 , and was mostly paid by the Central Storage and Warehouse Company and a grant from the USDA.
On May 7, 1991, arson investigators ruled the fire to be an accident that originated near a battery-propelled forklift. An informal year-end survey by The Madison Capital Times named the Butter Fire the most important local news story of 1991. In October 2011, more than twenty years after the flames, the Central Storage and Warehouse company finished reconstruction along with a freezer.
See also
List of non-water floods
References
Food processing disasters
Engineering failures
1991 fires in the United States
Madison, Wisconsin
May 1991 events in the United States
Industrial accidents and incidents in the United States
Warehouse fires in the United States | Wisconsin Butter Fire | [
"Technology",
"Engineering"
] | 944 | [
"Systems engineering",
"Reliability engineering",
"Technological failures",
"Engineering failures",
"Civil engineering"
] |
74,963,928 | https://en.wikipedia.org/wiki/Skin%20electrode%20gel | Skin electrode gels are used extensively to reduce electrical resistance when using skin surface electrodes, both for medical instrumentation such as EEG, EMG and EKG, and for electrical stimulation treatments such as TENS, electrotherapy, electroconvulsive therapy and defibrillation.
A typical electrode gel consists of a mixture of water, a thickener such as polyvinyl alcohol or carboxymethyl cellulose, and an electrolyte to increase conductivity.
Some electrode gels have been shown to pose a potential fire risk when high-energy pulses are used, as for example when defibrillators are used.
Skin electrode gels are also used by users of erotic electrostimulation to avoid skin burning.
References
See also
Medical lubricant
Electrophysiology
Electrotherapy
Medical equipment
Gels | Skin electrode gel | [
"Chemistry",
"Biology"
] | 169 | [
"Gels",
"Medical equipment",
"Colloids",
"Medical technology"
] |
74,965,286 | https://en.wikipedia.org/wiki/Capsule%20toy | A is a type of small vending machine in Japan, in which a user inserts a coin and turns the rotating lever to receive a released toy in a capsule. The term also refers to the actual toy that is released. As of 2023, with its diversification, active manufacturing of products and machinery as well as installation of wholesale machines, capsule toys are attracting attention as a new industry. Various names exist depending on the time period, region, and selling manufacturer, such as Gacha-Gacha, Gashakoko, Gachapon, Gashapon, Gacha, and P-cup, because these names are registered as trademarks by various companies. This article will use the term capsule toy.
Overview
Capsule toy is the generic term for miniature toys dispensed by capsule vending machines. There are also cases where products other than toys are included (as mentioned below). Each vending machine contains several different items (usually from the same series) and one of them is randomly dispensed.
Additionally, many capsules are partially transparent, allowing customers to see their contents, although some are not transparent and keep their contents a secret. These machines are operated by first inserting coins into the coin slot and then rotating the lever to dispense the product. Vending machines differ by the type and the number of coins they accept, such as the types of 10 yen (approximately 10 US cents), 50 yen, 100 yen, two 100 yen, and 500 yen. These prices are based on the value of the goods contained within the capsules sold by the machine. Besides, some models use special medal tokens sold separately instead of coins. In 2019 Bandai initiated the installation of Smart Gashapon machines that would accept electronic payments.
History
Capsule vending machines originate with small vending machines for gumballs that were first invented in the United States. They were eventually expanded to include the sale of small toys in capsule-shaped containers. This trend became popular in the United States. They were exported to Japan in 1965 from the United States and spread throughout the country in the 1970s.
As more manufacturers entered the market, the popularity of capsule toys continued to grow, especially with the introduction of licensed character-themed items in addition to original toys. They are often installed in candy stores and supermarkets, and there are often multiple machines in one location. With the rise in popularity of collectible figures, the variety of capsule toys has also increased significantly. Since the 2000s, there have been specialty stores that exclusively feature dozens to over one hundred capsule vending machines. Additionally, they are often installed in tourist destinations to offer local souvenirs and goods.
Unique examples of places where these machines have been installed include a train cabin of Wakayama Electric Railway's Toy Train as well as West Japan Railway's sightseeing Green Loop Bus. Furthermore, especially before COVID-19, they were also installed in departure lobbies of airports with many international flights, such as at Narita Airport and Kansai Airport. Since foreign currency exchange is generally limited to banknotes, these capsule vending machines were strategically placed so that travelers could use their unexchangeable 100 yen and 500 yen coins as a way to buy souvenirs.
As of the 2020s, adults are expressing Shōwa nostalgia by collecting capsule toys.
Similar vending machines
There are vending machines where coins are inserted and a dial is turned to purchase items not contained in capsules. Examples include gumballs, superballs, and trading cards (especially those known as Carddass). There are also other types of vending machines where coins are inserted, just like regular vending machines. These boxed toy machines with mechanisms like pulling a lever, kiddie rides, game machines (guaranteeing a prize of equivalent value), and in the past, there were even life-size hero figure machines (with theme music playing as capsules were dispensed).
Capsule contents
In the past, the encapsulated toys were mostly marketed towards kindergarten to mid-elementary school children, similar to products made by early capsule toy manufacturers in Japan, such as Value Merchandise (Nissho Boeki) and Cosmos. For example, there were erasers based on popular items and characters, such as supercars, Kaiju monsters, Kinnikuman, Super Deformed Gundam or other anime characters, and professional wrestlers. (Though, most of the time those "erasers" were just PVC rubber figures that did not actually erase.) Additionally, there are also machines that have a chance to dispense special prizes that are too large or valuable to be included directly within a capsule. In this case, the machine would dispense a winning capsule (or a winning ticket enclosed within a capsule) that can be exchanged at a store for the prize. For non-winning items, there are often participation prizes like Glico’s bonuses (similar to small toys previously common in cereal boxes in the U.S.). Subsequently, products like Bandai's Gashapon HG series helped capsule toys gain recognition in society, and other companies like Yujin joined in as well, resulting in numerous series becoming highly successful merchandise platforms. Since the late 1990s, the market has expanded to include not only children, but also older age groups, and the quality of merchandize has been improved (with slightly higher prices due to the higher quality). Since 2010, the primary reason for the price increase has been the rising manufacturing costs in China. While there are many niche and geeky products based on dramas, manga, anime, and games, there is also a wide variety of items ranging from traditional children's toys to realistic and surreal ones.
Furthermore, due to the growing societal awareness of promoting the healthy development of youth, companies have voluntarily been enforcing self-regulation by introducing age restrictions to limit the purchase of products featuring weapons or unsuitable character figures to ages 15 and above. However, age verification mechanisms are yet to be implemented in vending machines, allowing children below the age to purchase such items, which has raised concerns similar to those of adult magazine vending machines.
Since the 2000s, some capsule vending machines installed in tourist areas and specific regions have included limited-edition products (pins, straps, drawstring bags, coupons, etc.) as local goods. Japan Airlines (JAL) has previously offered limited edition capsule toys containing parts from retired aircraft.
Due to the nature of this sales format, buyers cannot choose the specific item of their choice. Instead, they often exchange duplicates with others to collect a complete set. Because of this practice, these types of toys are sometimes referred to as trading toys or trading figures, similar to items like collectible food toys, where customers also cannot choose the contents.
Derivative phenomena
Stemming from the aforementioned randomized sales system, where the purchased items are not revealed until they are dispensed, video games, especially social network games, also began to sell non-physical, in-game items and characters in this lottery-style sales method. These game types and other systems across the internet are often referred to as XYZ-gacha, where the XYZ is substituted with such words as avatar, item, complete, and other product names. In later years, problems emerged concerning the gambling-like addictive nature of the system as well as excessive charges, and regulations were mandated to disclose the markup percentage between the cost and the charge. A similar system is called a loot box in English, which refers to a container or box from which players in video games can receive randomized virtual items.
In the 2020s, as a form of derivative youth language, slang, and internet jargon, there is also a term called XYZ-gacha (such as parent gacha, child gacha, physical height gacha, face gacha, work-assignment gacha, etc.), which signifies situations where individuals are unable to choose their own paths and where their lives are determined (or have been determined) by what is given.
See also
Kinder Surprise
Gacha game
References
Vending machines
Wikipedia Student Program | Capsule toy | [
"Engineering"
] | 1,659 | [
"Vending machines",
"Automation"
] |
74,966,519 | https://en.wikipedia.org/wiki/Chinese%20character%20internal%20structures | Chinese character forms studies the external structure of Chinese characters, i.e. strokes, components, and whole characters, and their structural relations to the pure dimension of forms or appearances.
The internal structure of Chinese characters (Pinyin: hànzì nèibù jiégòu; Traditional Chinese: 漢字的內部結構; Simplified Chinese: 汉字内部结构) studies the relationship between the forms, sounds, and meanings of the characters, thereby explaining the rationale for character formation.
In the analysis of internal structures, Chinese characters are decomposed into internal structural components in relation to the sound and meaning of the character.
Internal structural components
The character-building units obtained by analyzing the external structure of Chinese characters are external structural components. In internal structures, Chinese characters are analyzed according to the rationale of character formation, and the basic unit of character formation is internal structural components, or internal components in short, also called pianpang (偏旁) or characters (字符).
In most cases, the components of the internal structure of a Chinese character are similar to the first-level components in the external structure, for example, the character 江 is decomposed into 氵 and 工 in both analyses. However, they are not always the same. For example, the character "腾" is decomposed according to the internal structure as "semantically related to '马' and phonetically related to '朕'", in a semi-surrounding structure; while the external analysis then simply split it according to the left-right structure.
The external structure splitting method is used only when the internal structure analysis cannot be decomposed according to the character formation rationale.
According to their sound-meaning relationship with the whole character, internal components can be classified into three categories: semantic component (義符, 义符, 意符, 意旁 or 形旁, phonetic component (音符, 音旁, or 聲旁) and pure (form) component (記號, 符號).
Any component related to the meaning of the character is a semantic component. For example: the component "扌" (hand) in characters "推" (push) and "拉" (pull), and "心" (heart) in "思" (think) and "想" (think).
A component related to the pronunciation of the character is a phonetic component. For example, "包" (bāo) in "抱" (bào) and "苞" (bāo).
A pure (form) component is neither related to the meaning nor to the pronunciation of the character. For example: "多" (duō) in "移" (yí, move), and "立" (lì, stand) in 拉 (lā, pull)".
Traditional internal structural classification
In Shuowen Jiezi, Xu Shen proposed the six categories (六書; liùshū; 'Six Writings') for the formation of Chinese characters, including
Pictograms (象形; xiàngxíng; 'form imitation') – A pictographic character consists of one semantic component which is a drawing of the object it represents, such as: 日 (sun) and 月 (moon). When created, character 日 was a simplified picture of the sun and 月 was like the moon.
Simple ideograms (指事; zhǐshì; 'indication') express an abstract idea with an iconic form, such as: 一 (one), 二 (two), 三 (three), 上 (up) and 下 (down). The whole character is a semantic component.
Compound ideographs (會意; huìyì; 'joined meaning'), are compounds of two or more semantic components to suggest the meaning of the character, for example: 武 ('military', formed from 戈 (dagger-axe) and 止 (foot)) and 信 ('truthful', formed from 人 (person, later reduced to 亻) and 言 (speech)).
Phono-semantic compound characters (形声; 形聲; xíngshēng; 'form and sound'); A phono-semantic character consists of a phonetic component and a semantic component, for example, 江 (river, semantic 氵, phonetic 工), 河 (river, semantic 氵， phonetic: 可).
Derivative cognates (轉注/转注; zhuǎnzhù; 'reciprocal meaning') are the smallest category and also the least understood. In the postface to the Shuowen Jiezi, Xu Shen gave as an example the characters 考 (kǎo, verify) and 老 (lǎo, old), which had similar Old Chinese pronunciations and may have had the same etymological root, meaning "elderly person", but became lexicalized into two separate words.
Rebus (phonetic loan) characters (假借; jiǎjiè; borrowing, making use of) are characters that are "borrowed" to write another morpheme which is pronounced the same or nearly the same. For example, the characters 令 (order) and 長 (long), These two characters originally were official titles. The whole loan character is a phonetic component.
Modern internal structural classification
The traditional Six Writings classification presupposed that each component in a Chinese character can either represent the sound or meaning of the character. But, after the long evolution of the Chinese writing system, quite a few components can no longer effectively play the roles. For example, component 又 in the characters 邓 and 鸡 can neither represent sound nor meaning and has become a pure-form component.
From the internal structure point of view, modern Chinese characters are composed of semantic components, phonetic components, and pure-form components.
These three types of components are used in combination to form the seven structures of modern Chinese characters: semantic component characters, phonetic component characters, pure form component characters, semantic-phonetic characters, semantic-form characters, phonetic-form characters, and semantic-phonetic-form characters.
Semantic component characters
Semantic component characters, or simply semantic characters, are composed of semantic components.
Single semantic component characters
Single semantic component characters are composed of one semantic component, and most of them correspond to pictograms and simple ideograms in the traditional six writings. For example:
田 (field), 井 (well), 門 (door), 网 (net) are ancient pictograms, and 门 (door), 伞(umbrella) are modern pictograms.
一 (one), 二 (two), 三 (three), 刃 (blade) are ancient simple ideograms, and 丫 (branch, fork), 凹 (concave), 凸 (convex), and 串 (string) are later simple ideograms.
Multi-semantic component characters
Multi-semantic-component characters are composed of two or more semantic components. They include compound ideographs in the traditional Six writings. For example,
Most multi-semantic component characters contain two semantic components, for example,
信 (trust): semantic components 人 (people) and 言 (words), trust what people say.
尖 (pointed, sharp, tip): 小 (small) at the top and 大 (large) at the bottom.
拿 (take): 合 (close) your 手 (hands) together to take.
Some characters are composed of three semantic components, for example,
掰 (break apart): Separate (分) something with both hands (手).
晶 (brilliant, crystal): three 日 (suns) are very bright.
Some characters repeat the same semantic components, for example,
从 (follow): Indicates that one 人 (person) follows another person.
炎 (flame): Two 火 (fire) represents rising flames.
森 (large forest): Three 木 (trees) means there are many trees.
Some are simplified characters:
尘 (dust): 小 (small) 土 (soil) particles, representing dust.
灭 (extinguish): Use 一 (like a cover) to suppress 火 (fire).
泪 (tears): 氵(water) from 目 (eyes).
There are some special cases
叵 (can not): turn 可 (can) to the opposite (right) side. (Shuowen)
乌 /烏 (crow, a pure black bird), 鳥/鸟 cannot see its eyes. (Note by Duan Yucai)
冇 (none, not have): 有 (have) taken away "二" (content).
Phonetic component characters
A phonetic component character, or shortly phonetic character, is composed of one or more phonetic components.
A single phonetic component character may be used to express a phonetic-loan meaning while its original or basic meaning is still understood by people. For example:
The pronunciation of the character "花" meaning "spending" is the same as that of the "花" which means "flower" in its original meaning. The latter can be regarded as the phonetic component of the former.
A single phonetic component character can also represent a syllable in a transliterated foreign word, for example, the characters in words "打" (dá, dozen) and "馬達" (mǎdá, motor).
Multi-phonetic component characters were produced during the development of writing systems. For example:
"新" (xīn) was originally a semantic-phonetic character, but its modern meaning of "new" has nothing to do with the original semantic component of "斤" (jīn, 0.5 kg), but the sounds are similar. In this way, "新" (xīn) then has two phonetic components: "亲" (qīn) and "斤" (jīn).
"耻” (chǐ, shame) used to be written as 恥 which is a semantic-phonetic character. The semantic component 心 (heart) has become 止 (zhǐ, stop), "耻” (chǐ) then has two phonetic components, "耳" (ěr) and 止 (zhǐ).
乒乓 (pīngpāng, ping pong), both forms and sounds of the two characters are derived from 兵 (bīng, soldier) with similar sounds.
Pure form component characters
A pure-form character is composed of one or more form components, which neither represent the sound nor the meaning of the characters.
Single-component characters
These characters are composed of single pure form components. Many of them were originally ancient pictographic characters, but due to the evolution of the glyphs, they no longer look like the object represented. For example:
日: The 日 character in the modern regular script is no longer of round shape.
月: It has become a ladder shape.
魚: Not quite like a fish now.
After tracing the origin of these kinds of characters, it is easy to associate them with the things they represent and obtain the correct meanings.
Some characters with single-form components are borrowed characters from ancient times. For example:
我: In oracle, it is like a weapon with a blade shaped like a saw, and was later used as a first-person pronoun. In modern Chinese, the original meaning is lost.
方: "Shuowen Jiezi" believes that the original meaning is a kind of boat, which has been borrowed to express the shape of a "square".
而: The ancient character was like a beard, now has been borrowed to be a conjunction in modern Chinese.
Some combined characters have been simplified and become single-form component characters.
广: The traditional Chinese character is "廣".
农: The traditional Chinese character is "農".
书: The traditional Chinese character is "書".
专: The traditional Chinese character is "專".
门: The traditional Chinese character is "門".
Multi-component characters
These characters consist of two or more pure-form components. Some of these characters came from ancient pictographic characters, but later became non-pictographic. For example,
角 (horn): This character in the oracle bone script looks like an ox horn.
鼎 (tripod): The oracle bone inscriptions are in the shape of a tripod.
鹿 (deer): In oracle bones, it resembles a deer.
Some came from ancient semantic-phonetic characters, and the semantic and phonetic components of these characters have lost their functions. For example:
騙 (piàn)： It originally meant to jump on the horse. It now means deception, and the semantic component 馬 (horse) and phonetic 扁 (biǎn) have become pure forms.
特: semantic 牛 and sound 寺, it originally referred to a bull, but now it means "special" and "unusual", and both components are pure forms.
穌：semantic 禾 (crop) and sound 魚 (yu2, fish), Duan Yucai's note in Shuowen says: "If the grain is scattered, pick it up with a loaf." The character now expresses the meaning of awakening or is used in a person's name.
Some are simplified characters. For example:
头 (head): The traditional Chinese character is “頭”, semantic component 頁 and phonetic component 豆. The simplified character component 大 and the two dots are pure-form components.
Some are from ancient ideographic characters. For example:
射 (shooting): The word "射" in oracle bone and bronze inscriptions is like pulling a bow and shooting, now neither 身 nor 寸 can express the sound or meaning of 射.
至 (to): in oracle bones, it is like an arrow shooting to the ground. According to the current glyph, the original meaning can no longer be seen, let alone the modern meaning of the word.
Semantic-phonetic characters
Semantic-phonetic characters (also called "phono-semantic characters", 意音字, 形聲字) consist of semantic components and phonetic components. The semantic component indicates the category of word meaning, and the phonetic component indicates (or prompts) the pronunciation of the character.
The phonetic components of some semantic-phonetic characters are of exactly the same pronunciation as the whole character. For example,
搬 (bān, move): 般 (bān).
銅 (tóng, copper): 同 (tóng).
辯 (biàn, debate): 辡 (biàn).
The sounds of the character and its phonetic component are the same except in tones. For example,
巍 (wēi, tall): 魏 (wèi).
拥 (yōng): 用 (yòng).
帳 (zhàng, account): 長 (zhǎng).
According to the experiment by Li (1993), among the 7,000 characters in the "Modern Chinese Common Character List", 5,631 are of semantic-phonetic structures. Considering that there are 479 polyphonic characters, the number of semantic-phonetic structures increases accordingly to 6,110. Among them,
there are 2292 items with characters and components of the same pronunciations and tones, accounting for 37.51%. There are 1110 items with characters and components of the same pronunciations but different tones, accounting for 18.17%
The phonetic components of some characters are also semantic components. For example:
娶 (qǔ, marry (a wife)): semantic 女 (female), phonetic 取 (qǔ), 取(take) also express the meaning.
駟 (sì, four horses of a cart): semantic 馬 (horse), phonetic 四 (sì), 四 (four) also represents meaning.
懈 (xiè, slack): 解 (xiè, scattered) represents sound and meaning.
Some phonetic or semantic components have some parts omitted. For example:
珊 (shān, coral): 冊 is 删 (shān) with the right part omitted.
氮 (dàn, nitrogen): 炎 is 淡 (dàn) with the left part omitted.
夜 (yè, night): semantic 夕, the rest is 亦 (yì) with some strokes omitted.
耆 (qí, senior over sixty years old), semantic 老 with lower part omitted, phonetic 旨
or semantic 老, phonetic 旨 with the upper part omitted.
There are six combinations of semantic components and phonetic components:
Left meaning (semantic) and right sound (phonetic), such as 肝 (gān, liver), 惊 (jīng, fear), 湖 (hú, lake);
Right meaning and left sound, such as 鵡 (wǔ, parrot), 剛 (gāng, firm), 甥 (shēng, nephew);
Upper meaning and the lower sound: 霖 (lín, rain), 茅 (máo, grass), and 竿 (gān, pole);
Lower meaning and upper sound: 盂 (yú， bowl), 岱 (dài, Mount Tai), 鯊 (shā, shark);
Outer meaning and inner sounds: 癢 (yǎng, itch), 園 (yuán, garden), 衷 (zhōng, heart), 座 (zuò, seat), 旗 (qí, flag);
Inner meaning and outer sound: 辮 (biàn, braid), 悶 (mèn, dull), 摹 (mó, imitation).
Modern character-making mainly inherits traditional character-making methods, but there are also innovations, such as combining the sounds and forms of two characters. For example,
甭 (béng, no need), meaning 不用 (bùyòn, no need), and sound derived from “bùyòng”.
巰 (qiú, compound of hydrogen and sulfur), 氫 (qīng, hydrogen) + 硫 (liú, sulfur), with parts omitted.
Semantic-phonetic characters account for more than 90% in ancient Chinese characters.
According to statistics, among the 7,000 modern common characters of the simplified Chinese character writing system, semantic-phonetic characters account for only 56.7%. The traditional Chinese character system is slightly higher.
Semantic-form characters
Semantic-form characters are composed of semantic components and pure-form components. They are also called semi-semantic components and semi-pure form components.
Many of these characters were originally semantic-phonetic characters. Due to subsequent changes in the pronunciation of the phonetic components or of the characters, the phonetic components could not effectively represent the pronunciation of the character and became pure-form components. For example:
布 (bù, cloth): used to have semantic (component) 巾 (scarf) and phonetic 父 (fù), the phonetic component is no longer 父.
江 (river): used to have semantic 水 and phonetic 工, now in Mandarin 工 (gōng) does not pronounce 江 (jiāng).
急 (jí, urgent): used to have semantic 心 (heart) and sound 及 (jí). Now the upper component no longer looks like 及.
Due to the simplification of Chinese characters, some phonetic components are no longer effective. For example:
灿 (càn, brilliant), not read as 山 (shān).
鸡 (jī, chicken), not read as 又 (yòu).
环 (huán, ring), not read as 不 (bù).
Some are modified from ancient pictographic characters. For example:
栗 (lì, chestnut): The upper part of the ancient Chinese character resembles the fruit on a chestnut tree. Now 覀 is a pure form component.
泉 (quán, spring): The oracle bone character looks like water flowing out of a cave. Now it has become components 白 (bái, white) and 水 (shuǐ, water). 白 is a pure-form component.
桑 Mulberry: in the oracle bone script, the upper part of 桑 resembles lush branches and leaves. The current 叒 is a pure-form component.
Phonetic-form characters
Phonetic-form characters are composed of phonetic components and pure-form components. This type of character mainly comes from ancient semantic-phonetic characters, and the semantic components lost their semantic roles and became pure-form components. For example,
球 (qiú, ball)： Originally refers to a kind of beautiful jade, with the semantic component 王 (also 玉, jade). Later, it was borrowed to represent a ball, and then extended to a round three-dimensional object, and 王(jade) became a pure-form component. The other component, 求 (qiú), remains a phonetic component.
笨 (bèn, stupid): Originally refers to the inner white layer of bamboo, with semantic component 竹 and phonetic 本. Later, the character was borrowed by sound to mean stupid.
华：This is a simplified character with the phonetic 化, and 十 is a pure-form component.
Semantic-phonetic-form characters
A semantic-phonetic-form character consists of all three kinds of components: semantic, phonetic, and pure-form components.
For example,
岸 (àn, bank, shore), originally had the semantic component ⿱山厂 and phonetic 干 (gàn). In modern Chinese, ⿱山厂 is not a character or radical with a sound or meaning, but 山 can still express meaning, while 厂 remains a pure form component.
聽 (tīng, listen), semantic 耳 (ear) and phonetic 壬 (ting3). In modern Chinese characters, the right part has become a pure form component.
Semantic-phonetic-form characters are very rare and the examples above are not quite persuasive. Whether it can be justified as an internal structural category remains to be further studied. (If not, the classification above can also be called the "New Six Writings")
Statistics on the internal structures of modern Chinese characters
According to Yang, among the 3500 frequently used Chinese characters of his experiment, semantic component characters are the least, accounting for about 5%;
Pure-form component characters account for about 18%;
semantic-form and phonetic-form characters account for about 19%.
The largest group is semantic-phonetic characters, accounting for about 58%.
The rationality of characters
Using texts to record a language is to establish a fixed connection between text symbols and language words. If this connection is arbitrary, it is irrational; if there is a reason for it, it is rational.
English words are mainly phonetic text, and their rationality mainly lies in using a combination of letters to represent the pronunciation of the corresponding word. Chinese characters are phonetic and semantic characters, and their rationality is mainly reflected in the use of phonetic components to express sounds and semantic components to express meanings.
Generally speaking, words with higher rationality are easier to learn and use. Because the unreasonable parts often require rote memorization. There are thousands of modern Chinese characters, and it is unrealistic to require every character to have high rationality.
The phonetic components and semantic components are related to the pronunciation and meaning of the character, so they are reasonable; the pure-form components are not related to the pronunciation or meaning of the character, and they are irrational.
Therefore, semantic component characters, phonetic component characters, semantic-phonetic characters, pure form component characters are irrational characters. The other characters are semi-rational characters.
Su defined the rationality of a character set as the proportion of rational components in all the internal components.
The formula is:
Rationality = (actual rationality value)/(maximum rationality value).
Professor Su's preliminary experiment results showed the rationality of modern Chinese characters to be about 50%, which is far lower than that of ancient Chinese characters.
Rational characters are easier to learn and often arouse students' interest.
In modern Chinese teaching, in order to enhance the rationality of Chinese characters, the traceability method is often used. For example: "日 (sun), 月 (moon), 山 (mountain), 水 (water), 牛 (cow), 羊 (sheep), 网 (net), 木 (wood), 目 (eye), 門 (door) and 刀 (knife)” are all pictographic characters from the etymology point of view. If the teacher makes some etymology analysis with the evolution of glyphs, he/she may achieve twice the result with half the effort.
The traceability analysis mentioned here is only for the convenience of teaching, rather than a comprehensive analysis of the origin and evolution of Chinese characters.
There is no need to trace the origin of characters that can be explained from the current situation. Only for those characters where the rationale cannot be seen from the current situation and it is easy to trace the origin to explain the rationale, can this method be employed.
See also
Chinese character classification
Chinese character forms
Chinese character meanings
Chinese character sounds
Chinese character structures
Notes
References
Works cited
Internal structures | Chinese character internal structures | [
"Technology"
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"Components",
"Chinese character components"
] |
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