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61,248,420 | https://en.wikipedia.org/wiki/Multicast%20routing | Multicast routing is one of the routing protocols in IP networking.
There are several multicast routing protocols supporting communications where data transmission is addressed to a group of destination computers simultaneously: Multicast Source Discovery Protocol, Multicast BGP, Protocol Independent Multicast.
Overview
Multicast routing is a method of transmitting to all subscribers registered in a group by one transmission unlike unicast routing (i.e. OSPF, RIP) which transmits 1: 1 necessary data.
To implement the multicast routing, Internet Group Management Protocol (IGMP) and a multicast routing protocol (Reverse-path forwarding, PIM-SM) for registration subscriber grouping and control traffic are required for multicast transmission. Regarding IP multicast, it is a technique for one-to-many communication over an IP network. IP multicast covers some part of common multicast routing protocol. IP multicast also describe IP multicast software (i.e. VideoLAN, — PIM module for the Quagga Routing Suite, UFTP, etc.). The multicast routing is specific and broad range of protocols for layer-3 routing protocol for multicast feature and it is defined in RFC 5110.
Routing mechanism
A multicast routing protocol is a mechanism for constructing a loop-free shortest path from a source host that sends data to the multiple destinations that receives the data. IPv4 uses Class D address (224.0.0.0 ~ 239.255.255.255)
IPv6 multicast provides the previous feature of IPv4 and a new IPv6 feature, allowing a host to send a single data stream to a subset of all hosts (group transmission) concurrently. There are four types of Well-Known IPv6 Multicast address range : ff02::1: All IPv6 devices,•ff02::2: All IPv6 routers,•ff02::5: All OSPFv3 routers,•ff02::a: All EIGRP (IPv6) routers.
The Multicast tree classification
There are two types of Multicast trees which are the Source-based tree and Group Shared tree.
Source based tree (SBT)
Its SSM (Source Specific Multicast) protocol. The maximum delay is short between End-to-end communication. It has poor scalability. (it is difficult to apply large network) Supported protocols include DVMRP, MOSPF, PIM-DM
Group Shared tree
It is Core-Based Tree, selecting one router in the network as the root and transmitting information through the root router. Maximum delay in the tree is longer than SBT(Source-based tree), The core router manages all the information, and the remaining routers manage the direction of the core and the multicast information requested by the current neighboring router. it has a Good Scalability (applicable to large networks). Supported protocols include CBT, PIM-SM, etc.
See also
Anycast
Any-source multicast
Broadcast address
Comparison of streaming media systems
Content delivery network
Flooding algorithm
Network speaker
Internet television
List of streaming media systems
Mbone, experimental multicast backbone network
Multicast address
Multicast lightpaths
Non-broadcast multiple-access network
Packet forwarding
Push technology
Session Announcement Protocol
Source-specific multicast
Broadcast, Unknown-Unicast and Multicast traffic
References
Internet architecture
Internet broadcasting
Television terminology | Multicast routing | [
"Technology"
] | 704 | [
"Internet architecture",
"IT infrastructure"
] |
61,248,470 | https://en.wikipedia.org/wiki/C13H13N3O3 | {{DISPLAYTITLE:C13H13N3O3}}
The molecular formula C13H13N3O3 (molar mass: 259.27 g/mol, exact mass: 259.0957 u) may refer to:
Ciclobendazole
Lenalidomide | C13H13N3O3 | [
"Chemistry"
] | 65 | [
"Isomerism",
"Set index articles on molecular formulas"
] |
61,249,402 | https://en.wikipedia.org/wiki/Quantum%20telescope | A quantum telescope is a concept for a telescope aimed at overcoming the diffraction limit of traditional telescopes by exploiting some properties of quantum mechanics, such as entanglement and photon cloning.
References
Proposed telescopes
Telescope types | Quantum telescope | [
"Physics"
] | 46 | [
"Quantum mechanics",
"Quantum physics stubs"
] |
76,448,046 | https://en.wikipedia.org/wiki/Kepler%20orrery | The Kepler Orrery is a group of animations created by Daniel Fabrycky and Ethan Kruse, which show exoplanets and stars discovered by the Kepler Space Telescope. 1,815 exoplanets and 726 planetary systems are in the animation.
The sizes of the planet orbits are to scale with each other, including the orbits of the planets in the local solar system out to Uranus. Current exoplanet discovery techniques are more likely to yield planets in tighter orbits around their stars. The sizes of the planets are at correct relative but not to absolute scale. The colors of the planets denote their estimated temperatures. All planetary systems seen in the animations have more than one transiting object, and the latest version was created by astronomy graduate student Ethan Kruse. In the description of the video Kruse said the size of the orbits are all to scale, but the size of the planets are not. The orbits are all synchronized such that Kepler observed a planet transit every time it hits an angle of 0 degrees (the 3 o’clock position on a clock).
History
The orrery was created by Fabrycky, then a postdoc at the University of California, Santa Cruz, largely due to an accident. When he created an animation of a six-planet system Kepler-11 for his work on a home computer in 2011, his son and daughter were found playing with the program. Fabrycky added the other 170 planetary systems known at the time into the program, added the Rimsky-Korsakov's "Flight of the Bumblebee" music to reflect the insect-like swarming of the planets, and called the result the "Kepler Orrery" in commemoration of a mechanical model of the Solar system (orrery) built in 1700s.
See also
List of exoplanets discovered by the Kepler space telescope
Visualization (graphics)
Orbital mechanics
External links
Kepler Orrery III at The Planetary Society
Kepler Orrery II at NASA
References
Sources
Kepler space telescope
Exoplanet search projects
Visualization (graphics)
2013 in science | Kepler orrery | [
"Astronomy"
] | 423 | [
"Astronomy projects",
"Exoplanet search projects",
"Space telescopes",
"Kepler space telescope"
] |
76,448,218 | https://en.wikipedia.org/wiki/Domenica%20Garz%C3%B3n | Domenica Garzon (Quito, December 11) is one of the first female theoretical physicists from Ecuador, recognized by the MIT Technology Review of the Massachusetts Institute of Technology as one of the top innovators in Latin America in the year 2022.
She is the co-founder of the Rikuna Center, a program that brings scientific research to vulnerable communities in Ecuador, and Water-Y, a project that seeks to use physics to solve water scarcity problems.
Research
Her research projects include astrophysics, and condensed matter.
Astrophysics
She conducts her research on gravitational waves at the University of Illinois at Urbana-Champaign and the Perimeter Institute for Theoretical Physics (Canada).
Condensed matter
Within this area, she conducted research with topological defects and graphene.
Months after the April 2016 earthquake that shook much of northern Ecuador's coast, access to clean water was a recurring problem, which led to the idea of solving this issue. Garzón, together with students from Yachay Tech University, invented a coating that makes this condensation process more efficient. The coating is an organic nanomaterial that increases the amount of water that can be condensed. The process ensures that the water is clean, as the condensation process is a natural purification process.
Exploration
Domenica is the co-founder of the "Rikuna" center ("to observe" in the indigenous Kichwa language). An interdisciplinary project that combines research, exploration, and scientific dissemination in the less explored areas of the Ecuadorian Amazon. In the first exploration, Domenica and the members of the Rikuna project discovered the first Cretaceous reptile reported in Ecuador. This was the first time a Mosasaur has been reported in the Ecuadorian Amazon.
Honors
In 2024, she became the first Ecuadorian Physicists to receive the AAUW doctoral fellowship (US).
In 2022, she was recognized by the MIT Technology Review magazine of MIT as one of the top innovators under 35 in Latin America.
In 2015, Domenica received the Abdón Calderón award from the mayor of the city of Quito for academic excellence.
In 2022, she became the first person in history to achieve the highest grade and be recognized by the School of Physics at Yachay Tech University as summa cum laude, where she was also acknowledged as the best undergraduate researcher.
In 2019, she received a bronze medal in the global physics contest, the university physics competition, with her team from Ecuador being the only South American team to receive a medal that year.
Early years
She grew up in the city of Quito, Ecuador. She completed her primary education at Virgilio Drouet school and her secondary education at La Dolorosa Private School. Later, she moved to the province of Imbabura to continue her studies at Yachay Tech University. After a few years, she decided to move to the United States to continue her research at the University of Illinois.
References
Alumni by university or college in Ecuador
21st-century Ecuadorian women
20th-century Ecuadorian women
Women inventors
Theoretical physicists
Year of birth missing (living people)
Living people
20th-century inventors | Domenica Garzón | [
"Physics"
] | 641 | [
"Theoretical physics",
"Theoretical physicists"
] |
76,449,249 | https://en.wikipedia.org/wiki/8-Bromocaffeine | 8-Bromocaffeine is a derivative of caffeine (a xanthine class), which is used as a radiosensitizer in the radiotherapy of tumors to increase the sensitivity of tumor cells to radiation treatment.
Synthesis
8-Bromocaffeine is produced in an electrophilic aromatic substitution by direct bromination with bromine in glacial acetic acid. Added sodium acetate acts as an acid scavenger for the hydrogen bromide that is formed. The elemental bromine can also be prepared in situ by oxidizing sodium bromide in an aqueous caffeine solution with hydrogen peroxide. Yields of 85% have been reported.
Properties
The caffeine derivative is a white and odorless solid with a melting point of 206 °C.
Uses
The substance acts as a radiomodulator, especially as a radiosensitizer In the radiotherapy of brain tumors, an increased sensitivity of the tumor cells, induced by 8-bromocaffeine, was observed.
References
Xanthines
Caffeine
Bromoarenes | 8-Bromocaffeine | [
"Chemistry"
] | 221 | [
"Alkaloids by chemical classification",
"Xanthines"
] |
76,449,414 | https://en.wikipedia.org/wiki/Spaceport%20Kii | is a commercial spaceport located in Kushimoto, Wakayama Prefecture in Japan. Japan's first private spaceport, it is operated by Space One, who are using it to launch their solid-fuel rocket KAIROS. As of 17 December 2024, two launch attempts have been made on the site, on 13 March and 17 December respectively, which both ended up being a failure.
Location and construction
Spaceport Kii is located near the southernmost tip of Honshu and is only a two-minute (1.9 kilometer) drive from Kii-Uragami Station in Nachikatsuura.
The launch site was funded by several Japanese corporations, including Canon Inc., Shimizu Corporation (who also constructed the site), and IHI Corporation. Ground broke on 19 November 2019.
Launches
The first launch attempt of the KAIROS rocket was scheduled on 8 March 2024, however it was delayed to the 13th due to a ship in too close of proximity. It launched on the 13th, but disintegrated just seconds later.
The second launch of KAIROS was initially scheduled for 14 December 24, but was ultimately scrubbed twice to 18 Dec due to bad weather. The 2nd launch had a successful liftoff, but ultimately suffered a loss of control nearing the end of the first-stage burn and was terminated.
Space One has stated that it plans to have around 20 launches of KAIROS a year.
References
External links
Space One official website
Rocket launch sites in Japan
Spaceports in Asia
2019 establishments in Japan
Buildings and structures in Kushimoto, Wakayama | Spaceport Kii | [
"Astronomy"
] | 322 | [
"Outer space stubs",
"Outer space",
"Astronomy stubs"
] |
76,450,769 | https://en.wikipedia.org/wiki/Mobile%20DevOps | Mobile DevOps is a set of practices that applies the principles of DevOps specifically to the development of mobile applications. Traditional DevOps focuses on streamlining the software development process in general, but mobile development has its own unique challenges that require a tailored approach. Mobile DevOps is not simply as a branch of DevOps specific to mobile app development, instead an extension and reinterpretation of the DevOps philosophy due to very specific requirements of the mobile world.
Rationale
Traditional DevOps approach has been formed around 2007-2008, close to the dates when iOS and Android mobile operating systems were released to the public. The traditional DevOps approach primarily evolved to meet the changing needs of the software development world with the paradigm shift towards continuous and rapid development and deployment (such as in web development, where interpreted languages are more prevalent than compiled languages). While traditional DevOps embraced agility and flexibility, mobile operating system providers steered towards a walled-garden approach with compiled apps with tight controls over how they can be distributed and installed on a mobile device. This difference in the mobile development mindset compared to what the traditional DevOps approach is advocating, is augmented further with the mobile applications to be deployed on a high number of varying devices and operating systems.
Eventually, the concept of Mobile DevOps took off as a trend around 2014-2015, in line with the fast growth of the number of applications in mobile app stores. As individuals and corporations alike are developing and publishing more and more mobile applications, the need for efficiency and shorter release cycles increased, which is addressed by the continuous feedback and continuous development approach within the concept of DevOps, while requiring a significant level of adaptation and extension of the traditional DevOps practices.
Mindset shift from traditional DevOps to mobile DevOps
Mobile DevOps has a unique set of challenges and constraints, which solidifies the fact that it needs to be approached as a separate discipline.
These challenges can be outlined as follows:
Platform-specific requirements and tight controls of mobile operating system providers, where for instance a macOS device is mandatory for iOS application development and release.
The walled-garden approach of distributing mobile apps, specifically applying to iOS applications, which comes with app review and app release delays that would not be needed in web development, for instance.
Code signing requirements that come with the walled-garden approach, which introduce additional processes in the mobile application build pipeline along with new security concerns.
An entire deployment cycle is re-run even in the slightest code change due to how applications are compiled and delivered to the users.
The final product is to be deployed to a wide variety of mobile devices worldwide, which requires extensive testing and user feedback.
Monitoring mobile applications require additional tools and approaches to be able to get data from an application running on a mobile device while respecting user privacy.
Frequent operating system updates by mobile platforms can require rapid adaptation of apps, introducing further complexity to the development and maintenance cycles.
Benefits of mobile DevOps
Mobile DevOps is not an abstract concept and offers a range of benefits that can help improve the efficiency and effectiveness of the mobile app development process. These benefits can even be quantified by collecting the data within the mobile application development lifecycle.
The benefits can be categorized into the following areas:
Faster Release Cycles: By automating tasks and streamlining the development process, mobile DevOps enables teams to deliver new features and updates more frequently.
Improved Quality: Automated testing and continuous monitoring help to identify and fix bugs earlier in the development cycle, leading to higher quality apps.
Optimized Resource Utilization: Mobile DevOps promotes optimized resource utilization by automating tasks and streamlining workflows. Furthermore, mobile DevOps practices like containerization can help to create more efficient and scalable development environments.
Increased Agility: Mobile DevOps allows teams to be more responsive to changes in the market and user feedback.
List of Dedicated Mobile DevOps Platforms
Even though it is possible to run a mobile DevOps cycle with most of the CI/CD platforms, they may require significant effort compared to non-mobile CI/CD (e.g. you need to bring your own infrastructure or it may require "reinventing the wheel" for commonly-used platforms like Jenkins).
To overcome the mobile-specific challenges specified, there are certain platforms that are dedicated to the lifecycle of mobile applications. These platforms exclusively focus on DevOps processes for mobile app development and are also referred as mobile CI/CD platforms.
Appcircle (Multiplatform | Cloud-based & On-premise)
Visual Studio App Center (Multiplatform | Cloud-based)
Xcode Cloud (Apple platforms only | Cloud-based)
See also
Continuous integration
Continuous delivery
Continuous deployment
Mobile app development
List of mobile app distribution platforms
Mobile-device testing
References
External links
Android Developer Documentation
Apple Developer Documentation
Flutter Developer Documentation
What is mobile DevOps? by Microsoft
Mobile software development
Software development process
Mobile applications
Software development
Software engineering | Mobile DevOps | [
"Technology",
"Engineering"
] | 991 | [
"Systems engineering",
"Computer engineering",
"Computer occupations",
"Software engineering",
"Information technology",
"Software development"
] |
76,451,701 | https://en.wikipedia.org/wiki/Bridge%20protection%20systems | Bridge protection systems prevent ship collision damage to a bridge by either deflecting an aberrant ship from striking the piers of a bridge, or sustaining and absorbing the impact.
History
Protecting bridges against ship collisions got attention of architects and regulators in the last third of the 20th century due to a marked increase in the frequency of collision accidents: worldwide, 30 major bridges collapsed in the 1960-1998 timeframe after being rammed by ships or barges, 321 persons were killed. The rate of smaller accidents is much higher: there were 811 serious accidents that did not cause a collapse just in the United States between 1970 and 1974, with 14 persons killed. Minor collisions are routine: the US Coast Guard gets 35 reports per day.
In the US, the turning point was the collapse of the Sunshine Skyway Bridge in 1980. Since then,
A "Committee on Ship/Barge Collision" appointed by the National Research Council issued a report on the history of ship collisions with bridges (1983);
The Louisiana Department of Transportation and Development issued vessel collision protection criteria for the bridge piers in Louisiana (1984);
Eleven states together with the Federal Highway Administration commissioned guidelines for the bridge protection design in the United States (1988);
The American Association of State Highway and Transportation Officials (AASHTO) issued a Vessel Collision Design Guide Specification in February, 1991, based on the previous study;
The International Association for Bridge and Structural Engineering published its "Ship Collision with Bridges" guide in 1993;
AASHTO adopted the LRFD bridge design specifications with provisions for bridge protection (1994).
Designs
There are several types of bridge protection systems used:
Fender systems attached to the pier with the goal to absorb the vessel impact. Their ability to withstand a typical ship collision is low. Fenders are built using a variety of materials:
thin-walled concrete box;
thin-walled steel membrane steel;
rubber.
artificial islands built with sand and rock core that is protected by riprap. The islands are quite effective in protecting the pier by pushing the ship away, but cause environmental damage to the river bottom and, while settling, might shift the bridge piers;
dolphins are made of piles driven into the river bottom in a group, with space in between sometimes filled with rocks and capped with concrete. The collision is absorbed via deformations of the structure;
pile-supported systems on dedicated piles that are driven into the bottom either vertically or at an angle ("batter piles"). The piles are connected together with rigid or flexible links, can be attached to the pier, and sometimes are fitted with fenders;
floating systems (cable nets and pontoons) have multiple problems from low efficiency to high construction and maintenance costs and environmental impacts, and are therefore used as a last resort, when the location of the bridge precludes the use of other designs.
Starlings are widenings of the bridge piers near their base, typically extending some distance above water level, providing some degree of reinforcement of the pier against impact.
Alternatives
Physical bridge protection systems designed to prevent catastrophic collisions are expensive and represent a "significant" share of overall construction costs. Therefore, alternatives are typically considered during the design phase:
fortifying the piers and superstructure to the point where they will be able to handle the impact, either on their own, or with the help of a fender system;
increasing the span length, so that the piers are away from the fairway and thus protected by the shallow water around them;
improving the navigational aids to reduce the probability of a catastrophic impact (60-85% of the collisions are due to pilot error.
Regulations
Highway designs in the US are subject to the AASHTO specifications, but the text does not contain specific procedures and recommendations. Railway bridges are built according to the "Manual for Railway Engineering" published by the American Railway Engineering and Maintenance-of-Way Association (AREMA).
In Australia, the subject is covered in the Australian standard AS 5100.2:2017, "Bridge design, Part 2: Design loads".
References
Sources
Bridge design | Bridge protection systems | [
"Engineering"
] | 809 | [
"Structural engineering",
"Bridge design",
"Architecture"
] |
76,452,557 | https://en.wikipedia.org/wiki/Texas%20Space%20Commission | The Texas Space Commission is a state agency of the Government of Texas. It was founded by the 48th governor of Texas Greg Abbott at Johnson Space Center in Houston on March 26, 2024.
References
External links
Official website
State agencies of Texas
2024 establishments in Texas
Government agencies established in 2024 | Texas Space Commission | [
"Astronomy"
] | 60 | [
"Outer space stubs",
"Outer space",
"Astronomy stubs"
] |
76,453,144 | https://en.wikipedia.org/wiki/Corpse-like%20obedience | Corpse-like obedience (, also translated as corpse obedience, cadaver obedience, cadaver-like obedience, zombie-like obedience, slavish obedience, unquestioning obedience, absolute obedience or blind obedience) refers to an obedience in which the obeying person submits unreservedly to another's will, like a mindless, animated cadaver.
Jesuit origin
The term originated with the Jesuit work by Ignatius of Loyola from 1553, the Letter on Obedience. It has also been dated to 1558. That text said, in Latin: "" which can be translated as "We should be aware that each of those who live in obedience must allow himself to be led and guided by Divine Providence through the Superior, as if he were a dead body". The concept, described in the Jesuit context as "fabled and misunderstood", has since been criticised by detractors of the Jesuit order as blind obedience. Jesuit supporters, in turn, refer to it as the "perfect obedience".
Modern use
The term is often associated with Germany (where it is known as ), where it refers to "both obedience and loyalty until death" or simply "absolute obedience" or "blind obedience". It has been associated with the discussion of German military and administration of the Prussian and Nazi eras and their passive adherence to carrying out orders, including those later judged to be war crimes (see also Prussian virtues, German militarism, , , and superior orders). The Law for the Restoration of the Professional Civil Service of 1933 has been credited with enforcing this idea in the Nazi German civil administration. Adolf Eichmann, one of the major organisers of the Holocaust, invoked this concept in his defence during his post-war trial.
The term has also been used in the context of other totalitarian regimes, such as communist states and parties. The concept has been described as promoted by works such as The Communist Manifesto or .
The concept has also been mentioned in the context of extreme interpretation of military discipline.
Some scholars have translated the term as zombie-like obedience. A similar variation occurs in Nigerian afrobeat artist Fela Kuti's song "Zombie" (from the album of the same name), in which Kuti calls Nigerian soldiers zombies as a critique of the country's military government.
See also
Desk murderer
Nuremberg defense
Respondeat superior
References
Political philosophy
Conformity
German words and phrases
Criminal defenses
Political terminology in Germany
Government of Nazi Germany
Corpses
16th-century neologisms
Historiography of Nazi Germany | Corpse-like obedience | [
"Biology"
] | 512 | [
"Behavior",
"Conformity",
"Human behavior"
] |
76,453,473 | https://en.wikipedia.org/wiki/Harcourt%20Butler%20Sr.%20Sec.%20School | Harcourt Butler Senior Secondary School, is a Delhi Govt aided boys school at Mandir Marg (earlier known as Reading Road) in Delhi, India. The school is affiliated to the Central Board of Secondary Education. It provides education from Class 1 to Class 12 having Science (Physics, Chemistry, Mathematics, Biology), Commerce and Arts stream in English and Hindi medium. This school is the only Government school having an Engineering drawing subject for class 11th and 12th.
History
The year of foundation of this school is 1889. The school was earlier known as Bengali Boys School, it was set up by a Bengali society.
In 1917, the British government took over its control and started funding its operations for the wards of British India Government employees. The existing structure of Harcourt Butler School was set up by Sir Spencer Harcourt Butler in 1917. Sir Spencer was the first member of education in the Viceroy’s Executive Council in India.
In winter School ran 6 months in Delhi and in summers 6 months in Shimla. This practice was discontinued in 1939 due to the Second World War.
Notable alumni
Satish Kaushik
Surinder Amarnath
Mohinder Amarnath
Nirmal Verma
Hari Krishna Shastri
Nasir Aslam Zahid
Rajesh Puri
V.R. Mehta
Satya Prakash Punj
References
External Links
Official website of Harcourt Butler School
Schools in Delhi
1917 establishments in India
High schools and secondary schools in Delhi
Technical drawing | Harcourt Butler Sr. Sec. School | [
"Engineering"
] | 286 | [
"Design engineering",
"Civil engineering",
"Technical drawing"
] |
76,453,587 | https://en.wikipedia.org/wiki/Ellen%20Graber | Ellen Graber is an American-Israeli research scientist in the field of environmental sciences. She is a senior scientist at the Volcani Agricultural Research Center (full professor equivalent), and is known for her work on biochar, for which she received the "Scientist of the Year Award" in 2013.In 2019, she began work on Cocoa tree resiliency, starting the Cocoa Cure Center within the Volcani Center. Her work was interrupted by the October 7 Hamas attack on Israel and the subsequent Israel–Hamas war, which led her to abandon some of her seedlings for five months to the elements of the Negev Desert. Some of the samples survived, and were studied for their resilient properties. 70% of the surviving plants were able to subsequently develop normally, and further research showed that they were all from the same genetic group.
References
Israeli scientists
Cornell University alumni
University of Michigan alumni
University of Texas at Austin alumni
Living people
Year of birth missing (living people)
Environmental scientists | Ellen Graber | [
"Environmental_science"
] | 203 | [
"American environmental scientists",
"Environmental scientists"
] |
76,453,972 | https://en.wikipedia.org/wiki/NGC%205953 | NGC 5953 is a peculiar spiral galaxy in the constellation Serpens. The galaxy lies about 80 million light years away from Earth, which means, given its apparent dimensions, that NGC 5953 is approximately 35,000 light years across. It was discovered by William Herschel on April 17, 1784. NGC 5953 interacts with NGC 5954 forming a pair known as Arp 91.
Characteristics
NGC 5953 is an unbarred spiral galaxy seen face on with many dust lanes. Two tidal plumes are visible, one to the northwest and one to the south of the galaxy. The spiral arms are flocculent and appear fragmented and are associated with star formation regions.
The galaxy has recently undergone intense star formation in the circumnuclear region around the nucleus where there are huge HII regions, probably as a result of its interaction with NGC 5954. The large HII region has been found to emit radio waves, appearing as a discrete source 5 arcseconds from the nucleus. A circumnuclear star ring with a diameter of 10–14 arcseconds is visible, which coincides with a disk of CO gas. Based on near infrared observations the ring hosts a red giant but not hot gas. The total star formation rate of the galaxy is estimated to be 2.56 ± 0.1 per year.
Active nucleus
The nucleus of the galaxy has been found to be active and it is categorised as a type 2 Seyfert galaxy or as a LINER. The most accepted theory for the energy source of active galactic nuclei is the presence of an accretion disk around a supermassive black hole. The black hole in the nucleus of NGC 5953 is estimated to have a mass of based on velocity dispersion.
A jet is visible to the north of the nucleus in radio waves extending for 0.3 arcseconds, which corresponds to a projected distance of 40 parsecs in the distance of the galaxy.
Nearby galaxies
NGC 5953 forms a pair with another spiral galaxy, NGC 5954, which lies 43 arcminutes away. The interaction has distorted NGC 5954. The pair is part of the NGC 5962 group or LGG 400. Other members of the group, apart from NGC 5962, include UGC 9925 and UGC 9951. A bit further away lie NGC 5951, NGC 5956, and NGC 5957.
References
External links
Unbarred spiral galaxies
Peculiar galaxies
Interacting galaxies
Seyfert galaxies
Serpens
5953
09903
091B
Markarian galaxies
55480
Discoveries by William Herschel
Astronomical objects discovered in 1784 | NGC 5953 | [
"Astronomy"
] | 542 | [
"Constellations",
"Serpens"
] |
76,454,060 | https://en.wikipedia.org/wiki/Roman%20Science%3A%20Origins%2C%20Development%2C%20and%20Influence%20to%20the%20Later%20Middle%20Ages | Roman Science: Origins, Development, and Influence to the Later Middle Ages is a book by science historian William Harris Stahl, published in 1962 by University of Wisconsin Press.
Synopsis
This book covers the history of science in the Latin-speaking West from its Greek origins to the time of the Graeco-Arabic revival, focusing on the influence of Greek science in the Latin world, and on how this influence shaped both scientific education and scientific culture all the way to the Middle Ages. The volume follows what the author calls "the handbooks movement", the production of encyclopedic material originating with Greek authors, such as Posidonius and Theon of Smyrna, and follows this tradition among the Romans. Stahl devotes specific chapters to Pliny, Solinus, Chalcidius, Macrobius, Capella, Boethius, Cassiodorus, Isidore, Bede, and other authors till about 1250, and discusses the genesis and subsequent development of the liberal arts in the Quadrivium and Trivium from the age of Plato (428–424 BC) and Isocrates (436–338 BC) till the Middle Ages and Renaissance.
Content
The initial section on "Classical Greek Origins" treats the discoveries of Aristarchus of Samos, Pythagora, the Sophists Hippias of Elis and Isocrates, Plato, the mathematician Eudoxus – credited with the invention of the Method of exhaustion –
and Aristotle. The mathematicians Euclid, Archimedes, Apollonius of Perga and Hipparchus are described in the section of the early Ellenistic tradition, together with the early botanist Theophrastus who headed the Peripatetic school after Aristotle, and Eratosthenes of Cyrenes. The first section of the work of Stahl ends with a chapter entitled "The Posidonian Age", from Posidonius (c. 135-51 BC) that marks the period when a Greek, mostly Stoic tradition, opens a "lengthy period of mutual admiration" between the Greek and Roman intellectuals. The chapter tells how the historian Polybius and the Stoic philosopher Panaetius were invited to the Scipionic Circle and of the friendship between Posidonius and Cicero. Though no work of Posidonius has reached us, his writings were used extensively by Cicero in his works, and influenced later authors such as Marcus Aurelius and Seneca.
Authors treated in the central section of Roman science, beside Pliny, include Cato the Elder, Cicero, Varro, Lucretius, Pomponius Mela, Vitruvius, Celsus, and Lucius Annaeus Seneca. Marcus Agrippa has a special mention for his approach of measuring the length and breadth of each province of the Roman Empire by computing distances recorded on the milestones on the imperial highways.
Nicomachus and Apuleius are treated in the chapter on the second century AD, while Latin neoplatonist encyclopedists Solinus, Calcidius, Macrobius, and Martianus Capella are treated in the chapter on Third- and Fourth-Century Cosmography.
The last part of the volume describes the short period of Ostrogothic renaissance, with Boethius and Cassiodorus, then moves to Isidore of Seville and Bede, and concludes with the 12th century and the School of Chartres. From the twelfth century onward, Latin translations of Arabic and Greek works were to revolutionise the intellectual life of Western Europe and diminish the predominance of the Latin encyclopedists.
The themes treated in the volume were anticipated in an article of the same title that Stahl published in 1959 in the journal Isis.
The author is critical of the way Roman authors treated quadrivium (arithmetic, geometry, music and astronomy) – but also geography – in their handbooks. Stahl faults the Romans and their handbooks for the low scientific level, the mechanical borrowing from one author to the next, the absence of new ideas, and the instrumental use of referencing – authors citing primary sources they had not read, and not acknowledging the secondary sources they had read instead.
The fact that any of these handbooks, Greek or Latin, quotes an original source cannot be taken for evidence that the compiler was himself acquainted with that source, as the quotations could have come from intermediate works.
Reception
Otto E. Neugebauer faults Stahl for ignoring relevant elements of Roman science: the Roman calendar, the agrimensores, and authors such as Manilius and Firmicus Maternus. He is also critical of Dahl's expansive use of the term "handbook" to cover a plurality of different types of works.
Funtowicz and Ravetz read in the work of Stahl a warning of how "science is an ongoing process, and not tables of enshrined truths". Thus science can degenerate to the banality and plagiarism denounced by Stahl if deprived of the stimulus of new research.
For Abraham Wasserstein, the merit of Stahl's work is that it provides a "history and aetiology of a great failure" of Roman civilization – that of not building on the foundations laid by their Hellenic predecessors, thus failing "the great task imposed upon them by history: to continue, develop, or at least transmit faithfully the inheritance of Greek science".
References
1962 non-fiction books
Books about the history of science
History of science | Roman Science: Origins, Development, and Influence to the Later Middle Ages | [
"Technology"
] | 1,135 | [
"History of science",
"History of science and technology"
] |
76,454,203 | https://en.wikipedia.org/wiki/Conocybe%20anthuriae | Conocybe anthuriae is a species of mushroom-producing fungus in the family Bolbitiaceae.
Taxonomy
It was described in 1997 by the Scottish mycologist Roy Watling and the Austrian mycologist Anton Hausknecht who classified it as Conocybe anthuriae.
It is notable as being one of the few Conocybe species which has a volva and subsequently was placed in Conocybe sect. Singerella along with the other volvate species.
Description
Conocybe anthuriae is a small brown volvate mushroom.
Cap: 0.6-1.5cm wide and up to 1cm high starting campanulate to convex and not expanding much with age. The surface is hygrophanous and brown but becomes paler or dirty yellow-orange in the centre with a yellowish white colour at the cap margins. It is smooth and lacking in striations when young but is radially sulcate when older with a pubescent coating when dry. Gills: Adnate, distant and pale cream coloured becoming pale yellowish brown with age. Slightly ventricose. Stem: 1.5-3cm long and 1-1.5mm thick tapering up from a bulbous base of up to 3mm wide. The surface is white to cream, not darkening with age and has a pruinose to pubescent coating with a striate texture. The volva is distinct, white and membranous with an uneven margin that is slightly denticulate. Spores: 10.5-13 x 7-8.3 μm. Ellipsoid with a prominent germ pore that measures 1-1.5 μm and a thick wall of up to 1.5 μm. The spores are yellow in water turning dark reddish brown in KOH with a wine red wall. Basidia: 18-25 x 10-14 μm. 4 spored with clamp connections.
Etymology
The specific epithet anthuriae is in reference to the cultivated Anthurium plants that the species was found growing with.
Habitat and distribution
The specimens studied by Watling and Hausknecht were found in Mauritius where they were growing in an open glass house on an Anthurium plantation in soil mixed with composted sugar cane.
References
Fungi described in 1997
Fungi of Africa
Fungus species
Bolbitiaceae
Taxa named by Roy Watling | Conocybe anthuriae | [
"Biology"
] | 493 | [
"Fungi",
"Fungus species"
] |
76,454,282 | https://en.wikipedia.org/wiki/Confocal%20endoscopy | Confocal endoscopy, or confocal laser endomicroscopy (CLE), is a modern imaging technique that allows the examination of real-time microscopic and histological features inside the body. In the word "endomicroscopy", endo- means "within" and -skopein means "to view or observe". CLE, also known as "optical biopsy", can analyse histology and cytology features of a tissue which otherwise is only possible by tissue biopsy.
Similar to confocal microscopy, the laser in CLE filtered by the pinhole excites the fluorescent dye through a beam splitter and objective lens. The fluorescent emission then follows similar paths into the detector. A pinhole is used to select emissions from the desired focal plane. Two categories of CLE exist, namely probe-based (pCLE) and the less common endoscopy-based endoscopy (eCLE).
CLE can be intubated to study the gastrointestinal (GI) tract and accessory digestive organs with a fluorescent dye. A variety of diseases, including inflammatory bowel disease (IBD) and Barrett's oesophagus, can be diagnosed by the magnified and in-depth view in combination with traditional endoscopy.
Significance
CLE can identify the lesions with a small depths of view under the tissue, in contrast to the surface level in conventional endoscopy. It also allows clinicians to discriminate benign or malignant lesions through real-time histological diagnosis by revealing the properties of the lamina at a cellular level.
An example is Whipple's disease. Conventional endoscopy presents a whitish-patterned duodenal mucosa. CLE, in comparison, generates two images –– the superficial images show capillary leak in duodenal mucosa while the deep images show cells of duodenal mucosa, including goblet cells and foamy macrophages in lamina propria. Compared to histological examination of the same duodenal site after periodic acid-Schiff staining, CLE identifies similar patterns of goblet cells and foamy macrophages.
Types
Two types of CLE have been invented, namely probe-based (pCLE) and endoscope-based CLE (eCLE).
Probe-based CLE
pCLE, developed by Mauna Kea Technologies, is a fibre bundle transit through the 2.8 mm working channel (the hollow hole) of the standard endoscope into the GI tract. With a fixed plane of imaging, each fibre acts as a pinhole to filter unwanted noise. The frame rate lies between 9 and 12 images/second.
Endoscope-based CLE
eCLE, developed by Pentax, is a confocal microscopy fixed at the end of the endoscopic tube. The integrated machine of eCLE is larger than the pCLE in diameter, making GI tract endoscopic intubation more difficult. eCLE has ceased commercially due to the camera's inflexibility.
Medical uses
Oesophagus
CLE is effective in detecting premalignant, including Barrett's oesophagus, and malignant (cancerous) lesions in the upper GI tract. The modifications of mucosa shown in histopathology as an index of malignancy can be identified under CLE, such as high-grade dysplasia. CLE can also be implemented to refer to the treatment of Barrett's oesophagus by measuring the lateral extent of neoplasia.
The Miami classification is the most popular system in oesophageal CLE diagnosis.
Stomach and duodenum
Similar to that of the oesophagus, CLE is able to detect early gastric cancer, as well as premalignant conditions, such as gastritis and intestinal metaplasia. CLE can detect and distinguish the stomach pit patterns to identify the disease in accordance with the Miami classification, which was refined in 2016 to include both pit patterns and the architecture of blood vessels. The refined classification allows clinicians to differentiate between neoplastic and non-neoplastic lesions.
The presence of Helicobacter pylori can also be identified using CLE by viewing the morphological changes in tissues.
Lower Gastrointestinal Tract
CLE reveals "soccer ball-like pattern" of narrower capillaries in malignant lymphomas; distorted architecture and fluorescein leakage from lumen in colonic adenocarcinoma; and blunt-shaped villi and crypts and increased intraepithelial lymphocytes in coeliac disease.
CLE can be utilized to identify adenoma and neoplasia in colorectal polyps and lesions. The Miami classification provides guidelines for clinicians to differentiate neoplastic and non-neoplastic lesions.
Inflammatory Bowel Disease (IBD)
CLE can be used for the identification of IBD and its subtypes (Crohn's disease and ulcerative colitis) based on the observation on morphological characteristics, such as architectural distortion, lowered crypt density, crypt irregularity and an abnormally high density of epithelial gaps. The prediction of IBD progression on non-inflamed epithelium is achievable, too, making way for a novel "treat-to-target" therapeutic approach.
Pancreas
Incorporating an EUS, CLE can accurately diagnose pancreatic cystic lesions, including mucinous and non-mucinous lesions. Special needles are used to collect fluid and cyst wall tissues for testing. Pancreatic ductal adenocarcinoma (PDAC) can also be viewed by CLE. Observing cystic lesions and PDAC, clinicians can identify early chronic pancreatitis and determine the malignancies of lesions.
Biliary duct
Biliary stricture can be viewed by CLE. The Miami and Paris classifications can be adapted to differentiate cancerous and inflammatory causes.
Others
The discrimination of inflammation and malignant tumor in lung and the urinary system may be done by using CLE and this is currently under research. Some usages such as oral and other head-and-neck cancer diagnosis have been proposed.
Molecular imaging
Antibodies of molecular targets are used to diagnose GI diseases by histology. CLE captures the fluorescence produced by specific antibodies binding to vascular endothelial growth factor (VEGF). Comparing the significant difference in fluorescent strength, clinicians can differentiate normal and neoplastic tissue. Molecular imaging with antibodies may be applied to CLE as a diagnostic benchmark due to high correlation with ex vivo microscopy.
The molecular imaging technique can be used in a similar manner in the examination of head and neck cancer using CLE, though the diagnostic targets may be different from those in the gastrointestinal tract.
Mechanism
Basic mechanism
The laser emitted by CLE through a pinhole is reflected by the beam splitter or a dichroic mirror and focused by an objective lens. The fluorescent dye in targeted tissue is excited and emits a specific wavelength. The emission from the focal plane of the tissue then is collected by the objective lens and the beam splitter. The laser is eventually filtered by a pinhole to reduce out-of-focus noise to enter the detector or photomultiplier tube.
Topical dyes
Cresyl violet and acriflavine can be used as topical dyes. Cresyl violet is a common stain in histology used for light microscopy sections, especially brain sections. In CLE, it can enhance the viewing of the cytoplasm, yet it limits tissue penetration and does not show anything about vasculature. Acriflavine is an antiseptic and dye. In CLE, it can stain the nuclei of GI surface epithelial cells. It is however subjected to cytotoxic and mutagenic properties, in addition to common side effects of irritation.
Intravenous dyes
Fluorescein is the most popular IV dye for CLE. Fluorescein is an FDA-cleared dye that is used in ophthalmology clinics in routine as it appears green under cobalt blue light. It is commonly applied topically to identify corneal diseases with slit lamp microscopes including corneal abrasion, ulcers, and infections; or intravenously to identify retinal diseases with angiography including macular degeneration and diabetic retinopathy. In CLE, it is usually administered intravenously immediately before the intubation of an endoscopic tube. The fluorescence is reported to be the most prominent from a few seconds to 8 minutes. Fluorescein is slowly eliminated; thus the fluorescence slowly decays up to a minimal detectable level after 1 hour, giving a time window for clinicians to investigate.
Recognition and optical flow algorithm
CLE's narrow field of vision makes it difficult for clinicians to identify the location and path of the probe, making it challenging to correspond the image obtained and the lesion location and direction. Research has proposed a crypt recognition algorithm, which predicts the pixel displacement by the moving angle and distance. By restoring the exploration path of CLE, clinicians can locate the sites of interest and improve diagnostic efficiency.
Image quality assessment
Research has proposed a new assessment method for filtering images yielded from CLE. As CLE often encounters image distortions, the degradation of image quality and loss of image information, eventually increase the difficulty of accurate diagnosis. A new image quality assessment (IQA) utilising Weber's Law and local descriptors assesses the quality and filters images with low diagnostic value.
Limitations
The variety of pathology conditions identifiable by CLE is limited. The histological diagnosis is limited to cancerous lesions and inflammation where the number of specific diseases identifiable is not numerous. Moreover, it requires specific training to operate CLE and correctly interpret CLE images, which are rarely used skills by experts in endoscopy. Owing to the narrow field of view, the applications of CLE might be restricted. Computer-aided diagnosis with AI technology may be beneficial in diagnosing CLE images.
Fluorescein is the only safe dye approved while cresyl violet and acriflavine are commonly used agents. The lack of choice of contrast agents may limit the application of CLE. For instance, patients allergic to fluorescein should never undergo CLE that involves the use of this intravenous dye.
The optical system consists of complex microscopic optical instruments, which are difficult to manufacture and assemble. Therefore, the tool is expensive.
CLE is mostly used in combination with other techniques instead of replacing conventional endoscopy with biopsy. CLE can only serve as a complementary to the traditional biopsy. By sharing the same working channel, conventional biopsy and CLE can be done alternatively by single intubation.
Adverse effects
The allergic properties of fluorescein, the common intravenous fluorescent dye for CLE, is the major culprit for the mild adverse events.
Intubation
CLE, similar to other diagnostic endoscopic techniques, may give rise to pancreatitis when used to examine the pancreas. The likelihood for pancreatitis is especially high in needle-based CLE. The incidence can be minimized by shortening the inspection time and avoiding excessive needle movement within the pancreatic cyst wall.
Fluorescein
Mild side effects, which are rare, include
Nausea
Vomiting with mild epigastric pain
Rash at injection site
Transient hypotension without shock
Diffuse erythema
These effects are manageable unless patients have prior experiences of them.
Cases of anaphylaxis are reported by ophthalmological uses of fluorescein. Prophylactic use of antihistamines can reduce the chances of allergic reactions or skin prick tests can identify the risk of allergic reactions.
Acriflavine
Acriflavine, another contrast agent for CLE, is potentially carcinogenic to humans due to its known mutagenic ability. The dye is therefore not approved by the FDA.
History
CLE is a modern, in vivo adaptation of confocal microscopy, the microscopic technique invented by Marvin Minsky in 1957.
Since 2004, CLE has been used for observing histopathological changes in gastrointestinal tissues.
See also
Confocal microscopy
Endoscopy
Contrast agent
References
Medicine | Confocal endoscopy | [
"Biology"
] | 2,587 | [
"Medicine"
] |
76,454,381 | https://en.wikipedia.org/wiki/Conocybe%20volvata | Conocybe volvata is a species of mushroom-producing fungus in the family Bolbitiaceae.
Taxonomy
It was described in 2001 by the K. Agregtitous Thomas, Anton Hausknecht and P. Manimohan who classified it as Conocybe volvata.
It is notable as being one of the few Conocybe species which has a volva and subsequently was placed in Conocybe sect. Singerella along with the other volvate species.
Description
Conocybe volvata is a small brown volvate mushroom.
Cap: 1.5-5.5 cm wide and campanulate, conical or conico-convex sometimes with an obtuse umbo. The surface is brown and may be concolorous all over or present with reddish brown colouration towards the centre disc and light brown colours towards the margin. It is hygrophanous and becomes greyish orange as the moisture content changes. The surface is smooth with fine striations visible when moist and the flesh is brownish white and up to 1.5mm thick at the centre. Gills: Adnexed to adnate, light brown to brown and close to crowded. Up to 3.5mm wide with lamellulae (partial gills) of different lengths. Stem: 5–14 cm long and 1.5-6mm thick becoming narrower at the apex. The surface has fine striations along its length and is white towards the apex with a pruinose coating visible with a lens and reddish brown towards the base. The volva is split in half when open and has a cottony texture. Spores: 9.5-14.5 x 7-9 x 6-8 μm. Ellipsoid to oviform-ellipsoid and frequently subhexagonal in face view. Smooth, thick walled and with an apically truncated broad germ pore. Pale brown to brown in KOH. Basidia: 19–26.5 x 11.5-15.5 μm. Clavate, 4 spored.
Habitat and distribution
The specimens studied by Thomas, Hausknecht and Manimohan were found in Kerala State, India where they were growing on elephant dung.
References
Fungi described in 2001
Fungi of Asia
Fungus species
Bolbitiaceae | Conocybe volvata | [
"Biology"
] | 481 | [
"Fungi",
"Fungus species"
] |
76,454,532 | https://en.wikipedia.org/wiki/Conocybe%20volviradicata | Conocybe volviradicata is a species of mushroom-producing fungus in the family Bolbitiaceae.
Taxonomy
It was described in 2011 by the mycologists Roy Watling, Mustafa Işıloğlu and Hayrünisa Baş Sermenlı who classified it as Conocybe volviradicata.
It is notable as being one of the few Conocybe species which has a volva and subsequently was placed in Conocybe sect. Singerella along with the other volvate species.
Description
Conocybe volviradicata is a small brown volvate mushroom.
Cap: 1.5cm wide and conical to campanulate. The surface is cinnamon to sienna brown but dries to a buff or yellowish cream colour. It is smooth and silky with a striate margin. The flesh is thin and up to 1mm in the centre. Gills: Almost free, crowded and pale ochre. Stem: 3cm long and 3mm thick with a cream colour surface and distinct striations running to the start of the volva. The base of the stem has a volva and a rooting base that is up to 2cm long. Spore print: ochre to cinnamon brown. Spores: 8-10 x 6-7 μm. Hexagonal with a distinct germ pore and thick wall. Sienna brown.
Etymology
The specific epithet volviradicata is named in reference to the volvate, rooting stipe.
Habitat and distribution
The specimens studied by Watling, Işıloğlu and Sermenlı were found growing on manured soil on the border of a vegetable garden in Southwest Turkey.
References
Fungi described in 2011
Fungus species
Bolbitiaceae
Taxa named by Roy Watling
Fungi of Asia | Conocybe volviradicata | [
"Biology"
] | 362 | [
"Fungi",
"Fungus species"
] |
76,454,547 | https://en.wikipedia.org/wiki/Lentilactobacillus%20kefiri | Lentilactobacillus kefiri is species of rod-shaped nonmotile bacteria. It is one of the main lactic acid bacteria species found in kefir and kefir grains. It can be bought and used as a probiotic.
Colonies on MRS agar are grayish, smooth, flat and 2 to 4mm in diameter. It is obligately heterofermentive, and can ferment lactose, maltose, melibiose, ribose, as well as sucrose, mannitol and trehalose to a weaker extent. It is not known to be pathogenic.
References
Bacteria and humans
Lactobacillaceae
Bacteria described in 1983 | Lentilactobacillus kefiri | [
"Biology"
] | 149 | [
"Bacteria and humans",
"Bacteria"
] |
76,454,827 | https://en.wikipedia.org/wiki/Temporins | Temporins are a family of peptides isolated originally from the skin secretion of the European red frog, Rana temporaria. Peptides belonging to the temporin family have been isolated also from closely related North American frogs, such as Rana sphenocephala.
Discovery
In 1996, the skin of the Rana temporaria was screened into a cDNA library, discovering three peptide precursors, known as Temporin B, Temporin G, and Temporin H. Once discovered, the three peptide, along with other temporins found in the sample, were separated from secretions of the frog's skin. Biological assays were performed, revealing that all temporins, in exception of temporin D and H, exhibited antibacterial activity. It was soon discovered that other species of frog also possess temporal, resulting in the discovery of more than 150 peptides from the temporin family. Some of the genera of frogs include the Amolops, Hylarana, Lithobathes, Odorrana, Pelophylax, Rana, and Hylarana.
Clinical uses
Temporins are a family of antimicrobial peptides (AMPs), which are highly targetable toward Gram-positive bacteria, allowing it to penetrate the cell wall and damage the inner membrane of the bacteria. These proteins are also capable of killing specific cancer cells when they are locally administered to a tumor, making it a good anticancer drug.
References
Peptides | Temporins | [
"Chemistry"
] | 301 | [
"Biomolecules by chemical classification",
"Peptides",
"Molecular biology"
] |
76,455,033 | https://en.wikipedia.org/wiki/Jorge%20Pinto | Eduardo Jorge Costa Pinto (born 20 April 1987) is a Portuguese environmental engineer, politician and member of the Assembly of the Republic, the national legislature of Portugal. A member of the LIVRE party, he has represented Porto since March 2024.
Early life
Pinto was born on 20 April 1987 in Amarante. He received a master's degree in environmental engineering the University of Porto in 2010 after producing a thesis titled Rainwater Harvesting Systems Implementation Inside Karunya University Campus for the Karunya University. He received a doctorate in social and political philosophy from the University of Minho in 2020 after producing a thesis titled Green republicanism: non-domination for an ecologically sustainable planet.
Career
Pinto is an environmental engineer by profession. He has worked abroad since 2008, in Lithuania, India, France, Italy and most recently in Brussels since 2012. He was a research associate at the University of Minho's Centre for Ethics, Politics and Society.
Pinto has written a number of books and comic books. The comic book Amadeo, a vida e obra entre Amarante e Paris (2018), about the life of painter Amadeo de Souza Cardoso, was written by Pinto and illustrated by Eduardo Viana. Rendimento Básico Incondicional - Uma defesa da liberdade (2019), which he co-authored, won the 2019 Philosophy Essay Prize from the Portuguese Philosophy Society. Tamem digo - uma história de migrações (2022), written by Pinto and illustrated by Julia da Costa, tells the story of Pinto's grandmother Maria do Carmo and other women who stayed behind during the wave migration to France under fascist rule in Portugal. He also wrote the plays Uma História Trágico-Marítima, which received an honourable mention in the 2017 INATEL/Teatro da Trindade awards, and Seis meses.
Between the ages of 18 and 25, Pinto was a member of the Socialist Party but became disillusioned with the party's lack of commitment to progressivism, environmentalism and the European left ideals. He was one of the founders of the LIVRE party and was part of the Contact Group, the party's executive body, from 2014 to 2020. At the 2015 legislative election Pinto was placed first on LIVRE's list of candidates in Europe but the party failed to win any seats in the constituency. He was a candidate for LIVRE at the 2019 and 2022 legislative elections in Porto but on each occasion the party failed to win any seats in the constituency. He was elected to the Assembly of the Republic at the 2024 legislative election.
Electoral history
Works
References
1987 births
Environmental engineers
Living people
LIVRE politicians
Members of the 16th Assembly of the Republic (Portugal)
Portuguese engineers
Portuguese expatriates in Belgium
University of Minho alumni
University of Porto alumni | Jorge Pinto | [
"Chemistry",
"Engineering"
] | 580 | [
"Environmental engineers",
"Environmental engineering"
] |
76,455,081 | https://en.wikipedia.org/wiki/Microneedles | Microneedles (MNs) are medical tools used for microneedling, primarily in drug delivery, disease diagnosis, and collagen induction therapy. Known for their minimally invasive and precise nature, MNs consist of arrays of micro-sized needles ranging from 25μm to 2000μm. Although the concept of microneedling was first introduced in the 1970s, its popularity has surged due to its effectiveness in drug delivery and its cosmetic benefits.
Since the 2000s, there has been discoveries on new fabrication materials of MNs, like silicon, metal and polymer. Alongside with materials, a variety of MNs types (solid, hollow, coated, hydrogel) has also been developed to possess different functions. The research on MNs has led to improvements in different aspects, including instruments and techniques, yet adverse events are possible in MNs users.
Microneedle patches or Microarray patches are micron-scaled medical devices used to administer vaccines, drugs, and other therapeutic agents. While microneedles were initially explored for transdermal drug delivery applications, their use has been extended for the intraocular, vaginal, transungual, cardiac, vascular, gastrointestinal, and intracochlear delivery of drugs. Microneedles are constructed through various methods, usually involving photolithographic processes or micromolding. These methods involve etching microscopic structure into resin or silicon in order to cast microneedles. Microneedles are made from a variety of material ranging from silicon, titanium, stainless steel, and polymers. Some microneedles are made of a drug to be delivered to the body but are shaped into a needle so they will penetrate the skin. The microneedles range in size, shape, and function but are all used as an alternative to other delivery methods like the conventional hypodermic needle or other injection apparatus. Stimuli-responsive microneedles are advanced devices that respond to environmental triggers such as temperature, pH, or light to release therapeutic agents.
Microneedles are usually applied through even single needle or small arrays. The arrays used are a collection of microneedles, ranging from only a few microneedles to several hundred, attached to an applicator, sometimes a patch or other solid stamping device. The arrays are applied to the skin of patients and are given time to allow for the effective administration of drugs. Microneedles are an easier method for physicians as they require less training to apply and because they are not as hazardous as other needles, making the administration of drugs to patients safer and less painful while also avoiding some of the drawbacks of using other forms of drug delivery, such as risk of infection, production of hazardous waste, or cost.
History
The concept of microneedles was first derived from the use of large hypodermic needles in the 1970s, but it only became prominent in the 1990s as microfabrication manufacturing technology developed. Later, the concept of MNs finally came into experimentation in 1994 when Orentreich discovered the insertion of tri-beveled needles to the skin could possibly stimulates the release of fibrous strand. The investigation on MNs’ potential to improve transdermal drug delivery gradually raised public awareness of MNs. Since then, there has been massive research conducted on MNs, contributing to the development of different materials, types, and fabrication methods of MNs. Application and adverse events are explored. In the 2000s, clinical trials on MNs’ use in drug delivery began.
Microneedles were first mentioned in a 1998 paper by the research group headed by Mark Prausnitz at the Georgia Institute of Technology that demonstrated that microneedles could penetrate the uppermost layer (stratum corneum) of the human skin and were therefore suitable for the transdermal delivery of therapeutic agents. Subsequent research into microneedle drug delivery has explored the medical and cosmetic applications of this technology through its design. This early paper sought to explore the possibility of using microneedles in the future for vaccination. Since then researchers have studied microneedle delivery of insulin, vaccines, anti-inflammatories, and other pharmaceuticals. In dermatology, microneedles are used for scarring treatment with skin rollers. As mentioned before, microneedles have also been explored for local targeted drug delivery at other drug delivery sites, such as the gastrointestinal, ocular, vascular etc., of which, ocular, vaginal and gastrointestinal have shown increasingnly convincing outcomes where they serve as a more efficient, localised drug delivery system, without the drawbacks of systemic exposure/toxicity.
The major goal of any microneedle design is to penetrate the skin's outermost layer, the stratum corneum (10-15μm). Microneedles are long enough to cross the stratum corneum but not so long that they stimulate nerves which are located deeper in the tissues and therefore cause little to no pain.
Research has shown that there is a limit on the type of drugs that can be delivered through intact skin. Only compounds with a relatively low molecular weight, like the common allergen nickel (130 Da), can penetrate the skin. Compounds that weigh more than 500 Da cannot penetrate the skin.
Materials of microneedles
Microneedles (MNs) consist of micro-sized needles arrays that are made of various materials exhibiting different characteristics and are suitable in the synthesis of different types of MNs. The selection of materials for formation of MNs greatly depends on the strength of skin penetration, manufacturing method, and rate of drug release.
Silicon is the first material used for the production of MNs. While the flexible nature of silicon allows easy manufacture of different sizes and types of MNs, silicon MNs can easily fracture during insertion in the skin. On the contrary, MNs made of metals like stainless steel, titanium, and aluminum, are non-toxic and possess strong mechanical properties to penetrate the skin without breakage. Nevertheless, metal MNs may cause allergic effects in some patients and it creates non-biodegradable wastes.
Polymer is also regarded as a promising material for MNs due to its good biocompatibility and low toxicity. Water-soluble polymers are more commonly used within the big polymer group and MNs tip breaking is more likely compared to MNs made of silicon and metal. Therefore, polymer is a more suitable material for dissolving MNs or hydrogel-forming MNs.
Types of microneedles
Since their conceptualization in 1998, several advances have been made in terms of the variety of types of microneedles that can be fabricated. The 5 main types of microneedles are solid, hollow, coated, dissolvable/dissolving, and hydrogel-forming. The distinct characteristic of each type of MNs allow a variety of clinical applications, including diagnosis and treatment.
Micro-sized needles in a microneedles (MNs) device can be as short as 25μm or even 2000μm in length depending on their types.
Solid microneedles
Solid MNs are the first type of MNs fabricated and are the most commonly used. Hard solid MNs have sharp tips that pierce through and form pores on the stratum corneum. A drug patch will then be applied to the skin for drug to be absorbed slowly and passively through numerous micropores.
This type of array is designed as a two part system; the microneedle array is first applied to the skin to create microscopic wells just deep enough to penetrate the outermost layer of skin, and then the drug is applied via transdermal patch. Solid microneedles are already used by dermatologists in collagen induction therapy, a method which uses repeated puncturing of the skin with microneedles to induce the expression and deposition of the proteins collagen and elastin in the skin.
Solid MNs help increase the permeability and absorption of drugs.
Hollow microneedles
Hollow MNs are designed with a hole at the tip and a hollow capacity that store drugs. Upon MNs insertion, stored drug is directly injected into the dermis and this effectively facilitates the absorption of either large-molecular or large-dosage drug. Yet, a portion of the drug can be leaked or clogged and it may hinders the overall drug administration. Since the delivery of the drug depends on the flow rate of the microneedle, this type of array could become clogged by excessive swelling or flawed design. This design also increases the likelihood of buckling under the pressure and therefore failing to deliver any drugs.
Coated microneedles
Coated MNs are fabricated by coating drug solution over solid MNs and the thickness of the drug layer can be adjusted depending on the amount of drug to be administered. A benefit of coated MNs is that less amount of drug is needed as compared to other drug administration route. This is because the layer of drug will quickly dissolve and delivered into the systemic circulation directly across the skin. The solid MNs which are removed afterwards may be contaminated by left-over drugs and the reuse of those MNs raise the concern of cross-infection between patients.
Coated microneedles are often covered in other surfactants or thickening agents to assure that the drug is delivered properly. Some of the chemicals used on coated microneedles are known irritants. While there is risk of local inflammation to the area where the array was, the array can be removed immediately with no harm to the patient.
Dissolving microneedles
Dissolving MNs are mostly composed of water-soluble drugs that enable the dissolution of MN tips when inserted into skin. This is a one-step approach which does not require the removal of MNs and is convenient for long-term therapy. However, incomplete insertion and delay dissolution is observed with the use of dissolving MNs.
This polymer would allow the drug to be delivered into the skin and could be broken down once inside the body. Pharmaceutical companies and researchers have begun to study and implement polymers such as Fibroin, a silk-based protein that can be molded into structures like microneedles and dissolved once in the body.
Hydrogel-forming microneedles
The primary material for the fabrication of hydrogel-forming microneedles (HFMs) is hydrophilic polymer that encloses drugs. This material draws water from interstitial fluid in the stratum corneum and results in polymer swelling and release of drug. Besides, the hydrophilic features of HFMs allow readily uptake of interstitial fluid that could be used for disease diagnosis.
Application and principle
Transdermal drug delivery
The most abundant transdermal drug administration route currently is via hypodermic needles, transdermal patches, and topical creams. However, these routes have limited therapeutic effects because stratum corneum serves as a barrier that reduces the entry of drug molecules into the systemic circulation and target tissues. The invention of MNs have retained the benefits of both hypodermic needles and transdermal patches while minimizing their cons.
Compared to hypodermic needles, MNs provide a pain-free administration. MNs are able to penetrate through the epidermis, but not any deeper to compress on nerve-ends to produce pain responses. The superficial penetration also lessen the infection risk.
Compared to transdermal patches, MNs are proven to be effective in producing micropores on the epidermis. The micropores facilitate the absorption of large molecules, like calcein and insulin, by 4 times via in-vitro skin models. In addition, MNs' direct drug delivery to systemic circulation avoided the first-pass effect in the liver. Significantly increasing the drug bioavailability, and the fast absorption into the systemic circulation also allowed a fast onset of action. Therefore, MNs could benefit diabetes treatment as common oral delivery would lead to a significant loss of insulin from degradation in the liver (first-pass effect) and insulin molecules are too large to be absorbed using common transdermal patches.
Furthermore, the high precision of MNs also allows drug reaching to localized tissues precisely, for instance, intradermal layers for cancer or the eye for ophthalmic disorder.
Vaccination
MNs are suitable for vaccination with their capability to deliver macromolecules and maintain a slow and sustained release of vaccine agents by using both coated and dissolving MNs. In addition, MNs' biodegradability minimizes biohazardous waste, unlike hypodermic needles. The application of MNs in vaccination would benefit people who avoid vaccination due to trypanophobia (fear of needles in medical settings).As of 2024, it has been found to generate an immune response similar to injection of measles and rubella vaccine.
Disease diagnosis and monitoring
Disease diagnosis and monitoring of therapeutic efficacy is possible by detecting several biomarkers in body fluid. However, current tissue fluid extraction methods are pain-inducing, and it may take up to hours or days for samples to be analyzed in medical laboratories. MNs could collect body fluid in an almost painless manner, and it could provide immediate diagnosis when combined with a sensor.
MNs allow penetration through the epidermis but not long enough to compress nerves in deeper layers, and thus, they are minimally invasive and almost painless. MNs' precision also allow the extraction of fluid surrounding diseased tissues, which may contain higher concentration of different biomarkers and specific biomarkers that are not present in the systemic circulation. These fluids provide more clinically significant and accurate values than those extracted from the systemic circulation, subsequently lowering the chances of underestimation of disease severity, especially for localized diseases.
Furthermore, MNs are capable of providing (near) real-time diagnosis, and it is easily administrated with simple procedures. Thus, MNs are potential candidates for Point-of-care (PoC) testing which could be conducted bedside.
Hollow MNs and hydrogel MNs could be used to diagnose and monitor several diseases including Cataracts, Diabetes, Cancer, and Alzheimer’s disease. For instance, hollow glass MNs and hydrogel MNs could extract skin interstitial fluid for the detection of glucose levels.
Collagen induction therapy
In the field of dermatology, MNs are more commonly known as collagen induction therapy. The therapy induces dermis regeneration via repetitive perforation of the skin using sterilized MNs. The repetitive penetration through the stratum corneum forms micropores, and these physical traumas to the skin sequentially stimulate the wound-healing cascade and expression of collagen and elastin in the dermis.
By making use of the human natural regeneration properties, microneedling could be used alone to treat scars, wrinkles, and skin rejuvenation, or in combination therapy with topical tretinoin and vitamin C for enhanced effect. Recent research has expanded the possibilities of MNs to treat pigmentation disorder, actinic keratosis, and promote hair growth in patients of androgenetic alopecia and alopecia areata.
MNs have been diverged into different forms, including Dermapen and Dermarollers. Dermarollers are hand-held rollers equipped with a total of 192 solid steel micro-sized needles arranged into 24 arrays, lengths ranging from 0.5-1.5mm. With the growing popularity of microneedling, MNs have also been commodified into home care Dermarollers, which are similar to medical dermarollers, except that the needles are shorter (0.15mm). This is a more budget-friendly device that allows individuals to perform microneedling at home.
Advantages
There are many advantages to the use of microneedles, the most prominent being the improved comfort of patients. Needle phobia can affect both adults and children, and sometimes can lead to fainting. The benefit of microneedle arrays is that they reduce anxiety that patients have when confronted with a hypodermic needle. In addition to improving psychological and emotional comfort, microneedles have been shown to be substantially less painful than conventional injections. Some studies recorded children's views on blood sampling with microneedles and found patients were more willing when prompted with a less painful procedure than traditional sampling with needles. Microneedles are beneficial to physicians as well, since they produce less hazardous waste than needles and are generally easier to use. Microneedles are also less expensive than needles as they require less material and the material used is cheaper than the materials in hypodermic needles.
Microneedles present a new opportunity for home and community-based healthcare. One of the biggest drawbacks of traditional needles is the hazardous waste that they produce, making disposal a serious concern for doctors and hospitals. For patients who require regular administration of medication at home, disposal can become an environmental concern is needles are placed in the trash. Dissolvable or swelling microneedles would provide those who are limited in their ability to seek hospital care with the ability to safely administer drugs in the comfort of their homes, although disposal of solid or hollow microneedles could still pose a needle-stick or blood borne pathogen infection risk.
Another benefit of microneedles is their lower rates of microbial invasion into delivery sites. Traditional injection methods can leave puncture wounds for up to 48 hours post-treatment. This leaves a large window of opportunity for harmful bacteria to enter into the skin. Microneedles only damage the skin to a depth of 10-15μm, making it difficult for bacteria to enter the bloodstream and giving the body a smaller wound to repair. Further research is required to determine the types of bacteria able to breach the shallow puncture site of microneedles.
Disadvantages
There are some concerns about how physicians can be sure that all of the drug or vaccine has entered the skin when microneedles are applied. Hollow and coated microneedles both possess the risk that the drug will not properly enter the skin and will not be effective. Both of these types of microneedles can leak onto a person's skin either by damage of the microneedle or incorrect application by the physician. This is why it is essential that physicians are trained how to properly apply the arrays.
Another concern is that incorrectly applied arrays could leave foreign material in the body. Although there is a lower risk of infection associated with microneedles, the arrays are more fragile than a typical hypodermic needle due to their small size and thus have a chance of breaking off and remaining in the skin. Some of the material used to construct the microneedles, such as titanium, cannot be absorbed by the body and any fragments of the needles would cause irritation.
There is a limited amount of literature available on the subject of microneedle drug delivery, as current research is still exploring how to make effective needles. In terms of design and manufacture, low drug loading is a key barrier towards reaching the clinics.
Safety profile
Apart from procedural pain, some common post-treatment adverse events (AEs) of MNs include temporary discomfort, erythema (skin redness), and edema. Pinpoint bleeding, itching, irritation, and bruising are also possible in some cases. However, most of the adverse side effects are not long-lasting and could be resolved spontaneously within 24 hours after the treatment, making MNs a rather safe tool. Photoprotection and minimal exposure to chemicals irritants are often advised for an effective recovery and lowered chance of skin inflammation.
Severe risks may be possible if there are technical errors during the procedure. For example, the usage of non-sterile tools might result in post-inflammatory hyperpigmentation, systemic hypersensitivity, local infections, etc. Moreover, if excess pressure is used over a bony prominence, it could lead to “Tram-track scarring”. But this could be avoided by using smaller needles and prevent over-pressurizing on top of these areas. In addition, if the patient is allergic to the either the drug used or the material of MNs, contact dermatitis is possible. Therefore, clinicians should be cautious towards patients with high risks of allergy.
References
Further reading
External links
Microneedles: a new way to deliver vaccines, Dawn Connelly, The Pharmaceutical Journal, 2021
Medical equipment
Drug delivery devices | Microneedles | [
"Chemistry",
"Biology"
] | 4,178 | [
"Pharmacology",
"Drug delivery devices",
"Medical equipment",
"Medical technology"
] |
76,455,149 | https://en.wikipedia.org/wiki/Azure%20Maps | Azure Maps is a suite of cloud-based, location-based services provided by Microsoft as part of the company's Azure platform. The platform provides geospatial and location-based services via REST APIs and software development kits (SDKs). The service is typically used to integrate maps or geospatial data into applications.
Azure Maps differs from Microsoft's other enterprise mapping service, Bing Maps, in its pricing model, focus on privacy, and its level of integration into the broader Azure cloud ecosystem.
History
Azure Maps was first introduced in public preview mode under the name "Azure Location Based Services" in 2017, primarily as an enterprise solution. The services was intended to add mapping and location-based functionality onto the existing Azure cloud services suite, seen as a critical part of Microsoft's broader Internet-of-Things (IoT) strategy.
The preview version included APIs which could be used to develop location aware apps for use cases such as logistics and mobility. In 2018, the software was renamed "Azure Maps," and became generally available to the public, and a number of new functions were added, including route calculation, travel time calculation, and incorporation of real-time traffic data and incident information.
Azure Maps was integrated with Azure IoT Central in 2018, which added tracking, monitoring, and geofencing capabilities. A set of mobility APIs on were added in 2019, with applications such as use in public transport apps and shared bicycle fleet management. “Azure Maps Creator,” which converts private facility floor plans into indoor map data, was also introduced in 2019. Some commentators linked these services to Microsoft's broader development of augmented reality products.
In 2020, Azure Maps Visual for Power BI was released, integrating location-based features and mapping capabilities into Microsoft's business intelligence software.
An elevation API (which was later retired), geolocation services, and an iOS and Android software development kit were introduced in 2021.
In 2022, support for historical weather, air quality, and tropical storm data was made generally available and custom styling for indoor maps was also introduced. In 2023, Azure Maps was certified as HIPAA compliant in a move to target healthcare and health insurance companies.
Functionality
Geocoding
Geocoding is one of the core functionalities of Azure Maps, converting addresses or place names into geographic coordinates. Batch geocoding is used to process large amounts of address data, a function used for route optimization and spatial analysis.
Reverse geocoding
Reverse geocoding derives human-readable information from geographic coordinates like longitude and latitude, used in navigation and by geographic information systems.
Routing
Azure Maps uses map data and routing algorithms to calculate the shortest or fastest routes between locations based on factors like vehicle size and type, traffic conditions, and distance. Routing also supports multi-modal routing, which include multiple modes of transport in a single trip, including cycling, walking, and ferries.
This functionality is used for location-based searches and route optimization in applications like fleet management, proximity marketing, and emergency services as well as logistics and delivery, urban planning, ride sharing apps, and outdoor activities.
Map visualization
The platform supports map visualizations that can be modified to reflect real-time data (including from IoT sensors) as well as historical data patterns. Visualizations include heat maps, street maps, satellite imagery and other custom data layers. Maps are rendered using raster or vector tiles which reduce the load of displaying large data sets or complex maps.
This can be used in various applications in areas like transportation, smart cities, retail and marketing, public health, and environmental monitoring. For example, it can be used for tracking the spread of diseases or measuring the impact of changing climatic patterns.
Geofencing and spatial analytics
Azure Maps supports polygonal geofencing, which enables the definition of custom geographic boundaries. Geofenced areas can be monitored in real-time for events of interest. For example, an application could send an alert when equipment or persons enter or leave a defined area.
Tools for analyzing historical geofencing data are also available via the APIs for optimization purposes.
Industry usage
Azure Maps' geofencing function has seen usage in the construction industry, designating hazardous areas for safety purposes and sending alerts if anyone enters the area. Private facility maps are used by construction companies for monitoring large construction sites to increase productivity and prevent accidents or damage.
In emergency management, New Zealand based company Beca has used Azure Maps to provide analysis on the impact of earthquakes to users, including information on the severity and location of an earthquake and the impact on affected properties. Alaska's Department of Transportation uses Azure Maps as part of an information system providing weather-related warnings and analytics to road crews.
Airmap, an airspace management platform for drones, uses Azure Maps.
Azure Maps has also been used in conjunction with Azure Monitor for risk monitoring by an insurance company.
Other companies that use or have used Azure Maps include BMW, Banco Santander, Jvion, MV Transportation, C.H. Robertson, Wise Skulls, Tata Consultancy Services, Providence Health and Services, Gas Brasiliano Distribuidora S.A., Shell plc, Persistent Systems, Phase 2 Dining and Entertainment, Symbio, HID, Globant, and Insight Enterprises.
Partnerships
Azure Maps and TomTom have been partners since 2016, and TomTom provides location data to Azure Maps and can process data from Azure Maps for mapping purposes.
In 2021, Azure Maps partnered with AccuWeather to make climatic data available via its APIs, making weather data along all parts of calculated routes available for mobility and logistics purposes.
Microsoft has partnered with Esri, the developer of ArcGIS, and there is cross-compatibility between Azure and ArcGIS so that data from Azure Maps can be integrated into ArcGIS and vice versa.
Azure Maps partnered with Moovit in 2019, a startup providing software that interfaces with public transport data. Moovit's database on global public transit networks, including information on which stations and facilities are wheelchair accessible, was linked to Azure Maps. This service was noted for its use increasing accessibility to public transport for the visually impaired by means of voice activated route planning assistance.
NORAD has used some Azure Maps functions for their NORAD Tracks Santa website during Christmas holidays.
Components
REST APIs
Various APIs cover the major functionalities across Azure Maps:
Data registry API
Geolocation API
Render API
Route API
Search API
Spatial API
Time zone API
Traffic API
Weather API
SDKs
Azure Maps SDKs uses MapLibre-style specifications and open source MapLibre GL-based libraries as a rendering engine. The Web SDK is used for developing web apps with maps and location-based data and functionality. It includes a map control module as well as modules with drawing tools. It also supports Azure Maps Creator and various spatial data formats.
The platform also includes a set of REST SDKs for developers integrating Azure Maps REST APIs into Python, C#, Java or JavaScript applications.
Azure Maps also includes Android and iOS SDKs used for developing applications for Android and Apple devices.
Azure Maps Creator
Azure Maps Creator is a tool for generating custom maps for locations like large office complexes, construction sites, or university campuses. These maps can then be integrated into applications and used with other Azure Maps functions for purposes such as wayfinding and maintenance and security in building automation contexts.
Azure Maps Visual for Power BI
Azure Maps is integrated with Microsoft Power BI, a graphical tool for producing data visualizations. Since July 2020, Power BI can be used in conjunction with Azure Maps for developing map-based data visualizations. This functionality entered general availability in May 2023.
See also
Bing Maps
Geographic information system software
References
External links
https://learn.microsoft.com/en-us/azure/azure-maps/
Microsoft software
Microsoft cloud services
Web mapping
Cloud computing
Cloud infrastructure
Cloud platforms
Web Map Services | Azure Maps | [
"Technology"
] | 1,598 | [
"Cloud infrastructure",
"Cloud platforms",
"Computing platforms",
"IT infrastructure"
] |
76,455,293 | https://en.wikipedia.org/wiki/Conocybe%20corneri | Conocybe corneri is a species of mushroom-producing fungus in the family Bolbitiaceae.
Taxonomy
It was described in 1979 by the Scottish mycologist Roy Watling who classified it as Conocybe corneri.
It is notable as being one of the few Conocybe species which has a volva and subsequently was placed in Conocybe sect. Singerella along with the other volvate species.
Description
Conocybe corneri is a small volvate mushroom.
Cap: 2-6cm wide and 1.5-2.5cm high starting conical then umbonate before flattening with age. The surface is dark purple with fine striations when young but it becomes wine red or reddish grey as it ages. It is hygrophanous and smooth with finely pubescent white hairs. The flesh is 1-1.5mm thick in the centre of the cap and is concolorous with the exterior surface. Stem: 10-16cm long and 2-3mm thick tapering upwards from a 5-7mm base. The surface is covered in fine pubescent hairs with spiraling striations up its length and is white towards the apex and base. The white floccose-membranous volva measures 8-12 x 7-9mm and splits irregularly or splits in half. Gills: Free or slightly adnexed, crowded and initially white turning pale ochre-cinnamon from the margins towards the stem. Spore print: Brown. Spores: 8.5-11 x 6-6.5 μm. Broadly ellipsoid to angular in face view and slightly flattened on one side in side view. Smooth with a very distinct apiculus and germ pore. Basidia: 26-30 x 11-12 μm. 4 spored, clavate and hyaline in water or alkaline mounts.
Etymology
The specific epithet corneri is named for the English mycologist E. J. H. Corner who collected the holotype specimen in 1940.
Habitat and distribution
The specimens studied by Watling were found on elephant dung in Malaya and on the forest floor in New Guinea. It was also cultivated for study in the Singapore Botanic Gardens by incubating elephant dung from the forest in under bell jars demonstrating that the growth of the mushroom is first visible in the early morning with the cap opening after dark whilst the volva remains immersed in the dung where it is inconspicuous.
References
Fungi described in 1979
Fungi of Asia
Fungus species
Bolbitiaceae
Taxa named by Roy Watling | Conocybe corneri | [
"Biology"
] | 535 | [
"Fungi",
"Fungus species"
] |
76,455,347 | https://en.wikipedia.org/wiki/Conocybe%20vaginata | Conocybe vaginata is a species of mushroom-producing fungus in the family Bolbitiaceae.
Taxonomy
It was described in 1979 by the Scottish mycologist Roy Watling who classified it as Conocybe vaginata.
It is notable as being one of the few Conocybe species which has a volva and subsequently was placed in Conocybe sect. Singerella along with the other volvate species.
Description
Conocybe vaginata is a small volvate mushroom.
Cap: 1.4-2cm wide starting hemispherical to ovoid to campanulate before expanding with age. The hygrophanous surface is smooth, dry and very striated with a brownish or greyish beige colour. Stem: 7-7.6cm long and 1-2mm thick. The surface is white and smooth with a pubescent coating all over but no striations. It is very fragile and hollow with a swollen base that sits inside the persistent, membranous white volva. Gills: Free to adnexed, greyish beige to pale rust coloured becoming more rust brown with age. They are narrow and ventricose. Spores: (11) 11.5-12.5 (13) x 8.5-10 x 6.5-8 μm. Broadly ellipsoid and smooth with a thick wall and large germ pore. Yellow-brown in water turning red-brown in KOH. Basidia: (17.5) 20-24 x 12-15 μm. Clavate and hyaline in water or alkaline mounts.
Habitat and distribution
The specimens studied by Watling were found under bamboo in Castanopsis and Araucaria woodland and on rotten wood in Castanopsis forests in New Guinea.
References
Fungi described in 1979
Fungi of Asia
Fungus species
Bolbitiaceae | Conocybe vaginata | [
"Biology"
] | 390 | [
"Fungi",
"Fungus species"
] |
76,455,985 | https://en.wikipedia.org/wiki/Conocybe%20volviornata | Conocybe volviornata is a species of mushroom-producing fungus in the family Bolbitiaceae.
Taxonomy
It was described in 2002 by the Egon Horak, Anton Hausknecht and Dennis E. Desjardin who classified it as Conocybe volviornata.
It is notable as being one of the few Conocybe species which has a volva and subsequently was placed in Conocybe sect. Singerella along with the other volvate species.
Description
Conocybe volviornata is a small volvate mushroom.
Cap: 1–2.5 cm wide and conical. The surface is pinkish-beige with a reddish-brown centre and a white fluffy to velvety coating from the pileicystidia. It is membranous, dry, thin and brittle and very strongly hygrophanous with the striations being visible from the margin to centre when moist. Stem: 4.5–9 cm long and 1.5-2mm thick tapering upwards slightly from a 6mm wide base. The surface is the same colour or paler than the cap with a dense covering of caulocystidia. It is fragile but solid rather than hollow with a membranous, persistent white volva at the base. Gills: Adnexed, crowded, pale rust brown. Spore print: Rusty ochre. Spores: 12.5-15 x 9.5-12 x 7.5-9.5 μm. Sublimoniform to broadly amygdaliform in side view, sublimoniform to subhexagonal to submitriform in front view. Smooth with a thick wall of up to 1.2 μm with a distinctive germ pore. Rusty ochre-brown in colour. Basidia: 15-24 x 10-12 μm. 2 spored, broadly clavate.
Habitat and distribution
The specimens studied by Horak, Hausknecht and Desjardin were found growing on soil in Indonesian rainforests dominated by Fagaceae trees.
References
Fungi described in 2002
Fungi of Asia
Fungus species
Bolbitiaceae
Taxa named by Egon Horak | Conocybe volviornata | [
"Biology"
] | 452 | [
"Fungi",
"Fungus species"
] |
76,456,050 | https://en.wikipedia.org/wiki/ELVIS%20Act | The ELVIS Act or Ensuring Likeness Voice and Image Security Act, signed into law by Tennessee Governor Bill Lee on March 21, 2024, marked a significant milestone in the area of regulation of artificial intelligence and public sector policies for artists in the era of artificial intelligence (AI) and AI alignment. It was noted as the first enacted legislation in the United States of America specifically designed to protect musicians from the unauthorized use of their voices through artificial intelligence technologies and against audio deepfakes and voice cloning. This legislation distinguishes itself by adding penalties for copying a performer's voice without permission, a measure that addresses the sophisticated ability of AI to mimic public figures, including artists.
Origin and advocacy
The inception of the ELVIS Act has been attributed to Gebre Waddell, founder of Sound Credit, who initially conceptualized a framework in 2023 that later evolved into the legislation. Representative Justin J. Pearson acknowledged Waddell's pivotal role during the March 4 House Floor Session on the bill. The act's development was a community-driven response, reflecting the collective initiative of the music industry to confront and address the challenges posed by rapid technological advancements. Tennessee Governor Bill Lee endorsed it as a Governor's Bill, and it was introduced in the Tennessee Legislature as House Bill 2091 by William Lamberth (R-44) and Senate Bill 2096 by Jack Johnson (R-27).
The ELVIS Act is an amendment to a 1984 law that was the result of the Elvis Presley estate litigation for controlling how his likeness could be used after death.
Lobbying from the recording industry
The legislative journey of the ELVIS Act included a broad coalition of music industry stakeholders, including:
These organizations, led by the Recording Academy and the RIAA, played roles in drafting the legislation, advocating for passage, and rallying support among the industry and legislators.
The act gained momentum through discussions that bridged industry concerns with legislative action. This collaborative process led to a proposal that specifically targets the use of AI to create unauthorized reproductions of artists' voices and images.
Opposition
The ELVIS Act saw industry opposition from the Motion Picture Association, including testimony in the House Banking & Consumer Affairs Subcommittee, including remarks that the law risks "interference with our member’s ability to portray real people and events". TechNet, representing companies like OpenAI, Google and Amazon expressed their opposition in the hearing to the bill as drafted, asserting that the language was too broadly written and could have unintended consequences. Other concerns around it being overly broad arose with concern that it could apply to cover bands, these concerns were addressed in the hearings with lawmakers mentioning that this was not the intention.
The bill passed the Tennessee House and Senate with a unanimous, bi-partisan vote including 93 ayes and 0 Noes in the House, and 30 ayes and 0 noes in the Senate.
Passage
By explicitly addressing AI impersonation, the ELVIS Act originated a legal approach to safeguarding personal rights, in the context of digital and technological advancements. It extends protections to an artist's voice and likeness, areas vulnerable to exploitation with the proliferation of AI technologies that occurred in 2023.
The legislation received widespread support from the music industry, signaling a significant step forward in the ongoing effort to balance innovation with the protection of individual rights and creative integrity. It was reported as underscoring Tennessee's commitment to its musical heritage and showed the state as a leader in adapting copyright and privacy protections to the modern technological landscape.
Artists including Chris Janson and Luke Bryan appeared at the signing ceremony hosted at Robert's Western World to support the new law and commemorate its passing.
Legal precedent
The ELVIS Act was reported as representing a development in the discourse surrounding AI, intellectual property, and personal rights. It was hoped by proponents to set a precedent for future legislative efforts both within and beyond Tennessee, offering a model for how states and potentially the federal government could address similar challenges. As AI technology continues to evolve, the act represents a foundational framework for protecting the authenticity and rights of artists, ensuring contributions remain protected.
The act prohibits usage of AI to clone the voice of an artist without consent and can be criminally enforced as a Class A misdemeanor.
This legislation's success was hoped by its supporters to inspire similar actions in other states, contributing to a unified approach to copyright and privacy in the digital age. Such a national response would reinforce the importance of safeguarding artists' rights against unauthorized use of their voices and likenesses.
References
Tennessee law
2024 in Tennessee
2024 in American law
Existential risk from artificial general intelligence
Computing legislation
Regulation of technologies
Regulation of robots
Data laws | ELVIS Act | [
"Technology"
] | 929 | [
"Existential risk from artificial general intelligence"
] |
76,456,164 | https://en.wikipedia.org/wiki/Conocybe%20crispella | Conocybe crispella is a species of mushroom-producing fungus in the family Bolbitiaceae.
Taxonomy
It was described in 1942 by the American mycologist William Alphonso Murrill who classified it as Galerula crispella.
It was reclassified as Conocybe crispella in 1950 by the German mycologist Rolf Singer.
Description
Cap: 1–2.5 cm wide and conical. The hygrophanous surface is pale cinnamon to clay brown with an ochre tint with most of the striations transparent and a minute pruinose surface visible with a lens. It is dry and very brittle. Stem: 4.5–9 cm long and 1.5-2mm thick with a bulbous base of up to 8mm thick. The surface is off white with a pale pink tint and minute white hairs over the entire length but absent striations. It is dry, hollow and extremely brittle. Gills: Free, crowded and pale rusty ochre. Spore print: Rusty ochre brown. Spores: 12–14.5 x 7-8 μm. Broadly amygdaliform in side view and ellipsoid in front view. Smooth with a thick wall of up to 1 μm and a distinct germ pore. Rusty ochre brown in colour. Basidia: 20-25 x 12-14 μm. 4 spored, clavate.
Habitat and distribution
The specimens studied by Singer were found amongst grass in shaded lawns and woods, on the soil or on dung from January to June in Argentina and in August in Florida. They have also been found on soil in gardens and in lawns in the Cook Islands, Mauritius, Seychelles and Réunion.
References
Fungi described in 1942
Fungus species
Bolbitiaceae
Taxa named by William Alphonso Murrill
Fungi of Florida
Fungi of South America
Fungi of Oceania
Fungi of Réunion | Conocybe crispella | [
"Biology"
] | 391 | [
"Fungi",
"Fungus species"
] |
76,457,038 | https://en.wikipedia.org/wiki/Kitumbako | Kitumbako Swamps (Kitumbako/Kitumbaku or Kitundu Hills) is a small valley located near the Uluguru Mountains of Tanzania, and the site usually attracts paleoecological and archaeological investigations despite its inaccessibility to humans. Many scientific investigations done on this montane valley involve the assessment of biodiversity, fauna, sediments, vegetation, and fire activity to examine the possibility of human activity. Human activity, although not concrete, has been confirmed to be connected to this site as well as other montane grasslands in East Africa. However, the presence of humans in the past and present along with other environmental factors were explored to uncover current developments of the grasslands and gain a deeper understanding of their environmental resilience. Thus, much of the information that is gathered and published is from the results of off-site archaeology is paramount to understanding and learning about Kitumbako Swamps, especially since there is not enough information about excavations being executed on the site.
Particularly, a lot of the off-site archaeological information found on the Kitumbako Swamps is integrated into scientific studies based on the Uluguru Mountains or the general East African Mountains. Much of the research and studies done that were directly associated with the Kitumbako Swamps were conducted by paleoecologist Jemma Finch and paleoarchaeologist Rob Marchant. The research papers published by both experts were an effort to understand the Eastern Arc forest mechanisms and gain insight to the environment's stability. For instance, Finch and Marchant have collaborated on work to reconstruct the paleoecological record in the Eastern Arc Mountains. Pollen and charcoal analyses were mainly used to gauge the long-term changes in the montane landscape, but also to find any underlying evidence of human activity. Finch and Marchant found the Poaceae pollen to be dominant in the Kitumbako record for approximately 13,000 years [during the Holocene], indicating the stability of the environment. They also found that the charcoal content showed little to no change in fire frequency over the same period, but it remained moderately high. Radiocarbon and other stable isotopes analyses were also used to measure environmental changes in Kitumbako. However, Finch and Marchant's findings were significant because it indicated whether East African Mountains' grasslands were more likely to be naturally conserved rather than disturbed by the presence of human beings. This inclination to the natural conservation of the montane grasslands can most likely be explained by sites inaccessible to humans.
Uluguru Mountains Deforestation and Farmland Effects on Forest Cover and Biodiversity
The Eastern African Mountains have been a region to study paleoecological data only a total of three times. Scientists have an affinity to study this region because it is considered a biodiversity hotspot. In particular, the Uluguru Mountains Before 1999, it was recorded that the Uluguru Mountains were home to about 16 endemic vertebrate animals and about 135 endemic plants, but between 1999 and 2001 surveys were done and changed the status of many of these endemic species. In other words, some of these endemic species became lost in the record. Deforestation was speculated to be the cause behind the missing endemic species in the record because many of the species inhabited the natural forests of the Uluguru Mountains. Therefore, it would make sense that forest loss, especially when it goes beyond a certain threshold, could lead to the extinction of a species. The Luguru people were permanent settlers in the Uluguru Mountains and controlled were named responsible for the 60% loss of forest.
However, an alternative reason for the loss of endemic species is the conversion of forests into suitable farmland. Between the 1950s and the 1970s, farmland was in high demand in different areas across the Uluguru Mountains because the range of crops planted required different environments, and it found the region to be agriculturally productive. Some of the plants grew better in lower elevations whereas others grew better at cooler temperatures and higher altitudes. However, to blame the extinction of species endemic to the Uluguru Mountains solely on the transition of forests into farmland would be incorrect. As previously explained, farmland can alter a species habitat but it does not necessarily mean that it causes extinction for all species. It depends on the agricultural practices which will determine how drastically the environment will change, like with the two species T. uluguruensis and B. uluguruensis.
Human interference is attributed to the losses of forest, and it can be traced back to Kitumbako. Kitumbako/Kitundu Hills had a total loss of 20 km2 of forest and it could be attributed to the changes in political power in 1964.
Paleoecological Investigations into Human Activity - Pollen and Charcoal Analyses
Paleoecological methods are used at Kitumbako because that is the most feasible way to understand the recent history of the Uluguru grasslands. These methods specifically track long-term changes in vegetation composition and fire regimes. Particularly, Finch and Marchant used these methods to investigate if the montane grasslands were secondary grasslands, which they defined it as a result of human activity. The most discussed methods involved pollen and charcoal analyses. Pollen analyses are typically used to measure and detect changes in vegetation composition and charcoal analyses are mainly used to investigate fire history.
References
Wikipedia Student Program
Paleoecology
Archaeological sites in Tanzania
Archaeological sites of Eastern Africa | Kitumbako | [
"Biology"
] | 1,068 | [
"Evolution of the biosphere",
"Paleoecology"
] |
76,457,599 | https://en.wikipedia.org/wiki/Adriana%20Salerno | Adriana Julia Salerno Domínguez (born 1979) is a Venezuelan-American mathematician, a professor of mathematics at Bates College, and a program director at the National Science Foundation. Her research interests include arithmetic geometry and arithmetic dynamics in number theory. She is also a mathematics blogger, the co-founder of the American Mathematical Society blogs "Ph.D. plus epsilon" and "inclusion/exclusion".
Education and career
Salerno was born in Caracas in 1979, and earned a licenciatura in mathematics from Simón Bolívar University (Venezuela) in 2001, advised by Pedro Berrizbeitia. She completed a Ph.D. in mathematics in 2009 at the University of Texas at Austin, with the dissertation Hypergeometric Functions in Arithmetic Geometry supervised by Fernando Rodríguez-Villegas.
She joined Bates College as an assistant professor in 2009. In 2016, she visited the Mathematical Association of America (MAA) headquarters in Washington, D.C., as Dolciani Visiting Mathematician. After serving as department chair, she took a leave from Bates College beginning in 2021 to become a program officer for the National Science Foundation, where she is a program director for algebra and number theory. In 2021, she was also elected vice president of the MAA.
Recognition
Salerno is a 2023 recipient of one of the Deborah and Franklin Haimo Awards for Distinguished College or University Teaching of Mathematics.
References
External links
Home page
Adriana Salerno, Calendar 2017, Latinxs and Hispanics in the Mathematical Sciences
1979 births
Living people
People from Caracas
Venezuelan mathematicians
Venezuelan women scientists
21st-century American mathematicians
21st-century American women mathematicians
Number theorists
Simón Bolívar University (Venezuela) alumni
University of Texas at Austin alumni
Bates College faculty
United States National Science Foundation officials | Adriana Salerno | [
"Mathematics"
] | 352 | [
"Number theorists",
"Number theory"
] |
76,458,209 | https://en.wikipedia.org/wiki/Conocybe%20mesospora | Conocybe mesospora is a species of mushroom-producing fungus in the family Bolbitiaceae.
Taxonomy
It was described as Conocybe mesospora in 1935 by the French mycologist Robert Kühner but the classification was invalid. It was described again in 1980 by the Scottish mycologist Roy Watling who classified it as Conocybe mesospora.
Description
Cap: 0.9-2.5 cm wide and semiglobate to convex or sometimes campanulate with a slight umbo. When young the centre is rust brown to chestnut brown with a lighter orange brown colour towards the margins and becoming lighter with age. It is smooth and hygrophanous with striations that are more distinct when moist. Stem: 2–6.5 cm long and 1–2.5mm or at most 4m thick with a small, distinct bulbous base that is 1.3-3mm or 6mm at most. The surface is pale yellow when young with a slightly darker base and it matures to an orangy yellow with a dirty coloured base. The entire surface has a pruinose coating. Gills: Close to distant, rusty yellow to light rusty brown. Spores: (6.5) 7.5-10 (11) x (4) 4.5-5.7 (6.5) μm. Smooth and thick walled with a broad germ pore. Yellow in water and rusty brown in KOH. Basidia: 19-27 x 8.5-10.5 μm. 2 to 4 spored.
Habitat and distribution
Found in woods, meadows and fields especially along paths in ditches and on the margins of fields and also found in dry places amongst grass and shrubs. May until October in Austria with a peak during September.
References
Fungi described in 1980
Fungi of Europe
Fungus species
Bolbitiaceae | Conocybe mesospora | [
"Biology"
] | 392 | [
"Fungi",
"Fungus species"
] |
76,458,403 | https://en.wikipedia.org/wiki/Conocybe%20subxerophytica | Conocybe subxerophytica is a species of mushroom-producing fungus in the family Bolbitiaceae.
Taxonomy
It was described in 1992 by Rolf Singer and Anton Hausknecht who classified it as Conocybe subxerophytica.
Description
Cap: 4-12 (15)mm wide and semiglobate to slightly campanulate or convex. When young the surface is rusty brown or light sienna brown becoming lighter and brighter with age to develop a tan colour with yellowish margins whilst the centre remains darker brown. Smooth and hygrophanous with only slight striations. Stem: 2–3.5 cm long and 0.8-1.5mm thick with a slightly bulbous 1-2mm base. The surface is light yellowish white when young and more yellow in the middle but matures to ochre or rusty yellow all over. The entire surface has a farinose-pruinose coating sometimes with slight striations running up the length of the stem. Gills: Adnate, subdistant, starting light yellow but maturing to rusty brown. Spores: (8) 9.5-12 (14) x (5.5) 6.3-7.5 (9) x (4) 5-5-7 (7.5) μm. Lentiform and smooth with a wall that is around 0.5 μm thick and a broad 1.2-2 μm germ pore. Yellow in water turning chestnut or rusty brown in KOH with a reddish tint to the wall in both water and KOH. Basidia: 15-22 x 8.5-11.5 μm. 4 spored.
Etymology
The specific epithet subxerophytica is named for the xerophytic environment in which the species is found.
Habitat and distribution
In dry grassland in open spaces and on South facing slopes with sandy, gravelly or loess soil. From May to June or sometimes until September. The specimens studied by Singer and Hausknecht were found in Austria and Greece.
References
Fungi described in 1992
Fungi of Europe
Fungus species
Bolbitiaceae | Conocybe subxerophytica | [
"Biology"
] | 445 | [
"Fungi",
"Fungus species"
] |
76,458,577 | https://en.wikipedia.org/wiki/Conocybe%20affinis | Conocybe affinis is a species of mushroom-producing fungus in the family Bolbitiaceae.
Taxonomy
It was described in 1969 by Rolf Singer who classified it as Conocybe affinis.
Description
Cap: (5) 7-12 (20)mm wide, semiglobose to convex or campanulate. The surface is uniformly light brown or tan but fades with age leaving the cap centre and margins slightly darker brown but as it is hygrophanous the colours can become darker after remoistening. It is smooth and without striations when young with distinct or indistinct striations with age. Stem: 2.8-6.5 cm long and 1-2 (2.5)mm thick with or without a slightly bulbous 1.3-3mm base. The surface is white-orange to dull pale orange when young and becomes darker with age with a fine pruinose coating all over which is almost floccose above the base when young. Gills: Adnate, close and darker brown than the cap and stem. Spores: (9) 10–12.5 (13.5) x (5.5) 6-7 (7.5) μm. Ellipsoid and smooth with a double wall of around 0.5 μm thick and a broad 1.8μm germ pore. Yellow in water turning reddish or rusty brown in KOH with a reddish tint to the wall in both water and KOH. Basidia: 17-22 x 9.7-11 μm. 4 spored.
Habitat and distribution
In open habitats such as meadows and road sides often with sandy or gravelly soil and also found on South facing slopes up to 300m in altitude. Found in May and June in Central Europe with collections from Argentina in parks and gardens during January and November.
References
Fungi described in 1969
Fungi of Europe
Fungus species
Taxa named by Rolf Singer
Bolbitiaceae | Conocybe affinis | [
"Biology"
] | 409 | [
"Fungi",
"Fungus species"
] |
76,459,550 | https://en.wikipedia.org/wiki/Tatra%20marmot | The Tatra marmot (Marmota marmota latirostris) is an endemic subspecies of marmot found in the Tatra Mountains. In the past, it was a game animal, but in the 19th century, its population drastically declined. It is a herbivore active in the summer, living in territorial family clans in the mountains from the upper montane to the alpine zone. It is one of the rarest vertebrates in Poland and is subject to strict legal protection. It is also legally protected in Slovakia. The and the classify the Tatra marmot as a strongly endangered subspecies (EN), while the Red List for the Carpathians in Poland designates it as "CR" – critically endangered. It is a relatively poorly researched animal.
History of discovery and research
The wider recognition of the marmot in Poland was influenced by the slow progress of settlement in the Tatra region, dating back to the privilege granted by Bolesław V the Chaste in 1255 to the Cistercian Abbey of Szczyrzyc: We also grant to the abbot: free hunting, all in the surrounding forests up to the mountains called Tatras. Historical accounts mention that over time, a group of hunters specializing in marmot hunting emerged, known as "whistlers".
Descriptions of Tatra marmots were very modest and mostly related to their hunting value. Hungarian pastor wrote in 1774: The Carpathian marmot resides in the highest mountain peaks' dens in summer and winter. It feeds on roots and herbs and has fat, tasty meat. The meat, skins, and especially the fat, which had wide applications in folk medicine, were valued.
Various authors wrote about marmots; in 1719, teacher , in 1721, Polish naturalist and Jesuit Gabriel Rzączyński, in 1750, Gdańsk naturalist Jacob Theodor Klein, and in 1779, Polish naturalist and clergyman Jan Krzysztof Kluk mentioned "whistlers" in the Carpathians. Marmots were hunted almost without restrictions until around 1868, and on the Hungarian side of the Tatras until 1883 when regulations protecting this species were introduced.
In 1865, the first description of marmot biology was published. The author of the work About the Marmot was Maksymilian Nowicki – co-founder of the , researcher of Tatra fauna and flora, and a pioneer of nature conservation in Poland. Nowicki, using the name Arctomys ( – bear, and – mouse, rat) as the generic name for marmots, used the term "little bear mouse," while Ludwik Zejszner, writing at the same time, used the term "bear mouse": this peculiar little animal looks like it consists of two others; with a head similar to a mouse, and the rest of the body like a bear, covered with long hair similar to martens. Highlanders call it a marmot because of its special barking, as the individual barking sounds are so drawn out that they bear a great resemblance to whistling... The marmot makes very long burrows in the Tatra hollows, lining them with moss, grass, and, like many animals, undergoes hibernation. At the end of summer, it stores numerous root supplies in its burrows and, having fattened up excessively, falls asleep in this winter abode, only waking up completely emaciated with spring.
Systematics and evolution
Belonging to the family Sciuridae, the species Marmota marmota began to inhabit European territories already in the Pleistocene. It occurred over a vast area – from present-day Belgium and the shores of the English Channel to the Pannonian Basin. In the Holocene, with the warming climate, marmots had to choose more favorable locations. The moderate warmth of forested areas was not suitable for them, as their bodies are not well adapted to higher temperatures. They found cooler habitats in the elevated mountain ranges of Europe. Over time, they had to narrow their territories to the Alpine range and the Tatra Mountains. The separation of the Alpine population from the Carpathian one could have occurred from 15 to 50 thousand years ago, but for many years, no differences were noticed between the marmot living in the Tatras and its Alpine cousin, and both populations were treated as geographically separated locations of the same species.
In the late 1950s and early 1960s, Czechoslovak scientists undertook comparative studies. For this purpose, on 31 May 1961, a marmot was shot from a colony in . The holotype studies were conducted by , a zoologist from the agricultural university in Brno, who found significant differences in the structure of the nasal bones compared to representatives of Alpine populations. After conducting additional comparisons of the results of cranial measurements of the skulls of 10 Tatra marmots (selected from 16 obtained for study) and 40 marmots from the Alps (27 skulls were personally examined, and the measurement data of 13 were the result of Gerrit Miller's work from 1912), Kratochvíl concluded that there was a regularity in the comparative group, namely, that the anterior, facial part of the nasal bone was significantly wider and longer in Tatra marmots than in animals from the Alps. Additionally, he found that marmots living in the Tatras are smaller than their cousins and have slightly different fur coloration. Ultimately, Kratochvíl classified marmots from the Tatras as a separate subspecies, M. marmota latirostris, while marmots from the Alpine population were designated as M. marmota marmota. Some zoologists question whether the observed differences could be merely manifestations of individual variability within the small population. However, genetic studies have not yet been conducted to settle this matter.
Etymology
The generic name Marmota may derive from Gallo-Romance languages, meaning "murmuring" or "purring", or from Latin, being associated with the term mus montanus, which translates to "mountain mouse". The subspecies epithet latirostris originates from two Latin words: the element lati– comes from Latin lātus, meaning "wide", and –rostris from Latin rōstrum, referring to the nose or beak, and together it can be translated as "broad-nosed". The epithet refers to the flattened and wider facial part of the nasal bone (os nasale) of the animal compared to representatives of the Alpine population.
Morphology
The Tatra marmot is one of the largest rodents in Europe. It is similar in size to a domestic cat, with a massive torso. Its length, including the head, ranges from 45 cm to 65 cm (although another source by the same author provides a range of 40–60 cm). In spring, the body mass of adult males ranges from 2.7 to 3.4 kg, while females weigh between 2.5 and 3.0 kg. During the season from spring to autumn, marmots start to consume more calories, taking in more carbohydrates from grass seeds, and their brown adipose tissue significantly expands, creating an energy reserve for the next hibernation period. Consequently, the body mass of marmots begins to increase noticeably during this period and can reach over 6 kg by autumn, with over 2 kg attributed to fat tissue. The fluffy tail measures between 13 and 17 cm.
The primary fur consists of long, strong, and thick guard hairs, with the down hair being dense, composed of shorter, woolly, and slightly twisted hairs. The fur color is described as reddish-brown transitioning to dark brown-black. The hair coloration is highly varied, with black or dark brown dominating at the base, while shades of fawn, black, or reddish prevail higher up, fading to fawn or beige at the ends. The fur on the abdomen is lighter, ranging from light beige to yellowish. The head is covered with shorter hair, usually dark, black, or gray, with a light patch between the eyes. The muzzle is lighter, with a grayish tone, while the tail is blackish-brown, with a black tip. The fur of young individuals under 1 year old is notably darker and fluffier. Moulting typically occurs once a year, around June. Females, weakened by nursing new offspring, may have incomplete fur, and moulting may be delayed by about four weeks. As they age, the fur becomes more twisted and bushy. Older marmots, especially after hibernation, may have areas of thinning fur on their backs and tails.
Five rows of whiskers, measuring up to 8 cm in length, grow on the sides of the marmot's muzzle, with sensory hairs also distributed on the eyebrows. Marmots do not have sweat glands. The forehead is flat and wide, with short (2–2.5 cm), densely furred ears almost entirely concealed in the head's fur. The eyes are small and black. The front paws are short, robust, and dexterous, equipped with four hairy toes ending in claws measuring from 2 to 2.5 cm, which serve as useful tools for digging burrows and holding food. The muscular hind limbs end in five toes with sharp claws.
The external surface of the incisors is covered with hard enamel with longitudinal grooves, whose color changes with the animal's age, starting white in juveniles and darkening to orange and nearly brown with age. The posterior, concave surface of the incisors is made up of brittle dentin. The incisor's occlusal arrangement is scissor-like. The dentition for marmots is: .
In females, there are five pairs of mammary glands.
Morphological in comparison to the alpine marmot
The main feature that allowed the Tatra subspecies of marmot to be distinguished was the dimensions of the facial part of the nasal bone:
Craniological comparisons (, 1961)
Furthermore, Tatra marmots are characterized by lighter fur and have a grayish-brown coloration, while the alpine subspecies has a darker brown coloration, often with a reddish hue. M. marmota latirostris has a smaller body mass. However, sources do not provide details of this difference.
Despite differences in the habitats of both subspecies (alpine marmots occupy locations at altitudes up to 3200 m above sea level), no differences have been observed in behavior and way of life.
Lifestyle
The Tatra marmot is a diurnal animal with territorial and social behavior. It is monogamous, and individual families join colonies, with the nucleus typically being a dominant pair of animals.
Annual life cycle
The annual life cycle of the marmot consists of two periods: summer activity and hibernation.
Summer activity
The summer activity of the marmot begins around April and May and lasts until the second half of September or the first half of October. The earliest emergence of marmots on the surface has been observed on April 22, while the latest on May 10. This period lasts 139–158 days (or 139–161), with an average of 148 (or 150.7).
The first spring activity after awakening from winter hibernation is associated with the mating season. the estrous cycle typically occurs in the second decade of May. Mating takes place both inside and outside the burrow. Gestation lasts about 33 days, and the young are born in the second decade of June. Usually, from 1 to 6 offspring are born, most commonly from 2 to 3. They remain under the care of the female in the burrow until the second half of July. They start consuming solid food at the age of 8 weeks. They will only become independent after 3–4 years when they reach sexual maturity.
The beginning of summer activity is also marked by the search for new locations. Marmots migrate up to a distance of 3000 meters.
During the summer period, marmots spend their time foraging (43.9%) and patrolling the territory (40.3%). Other activities such as moving, gathering winter supplies, digging and tidying burrows, playing, hygiene, typically account for only 8.9% of their time. Spending time inside the burrow during the day constitutes an average of 6.9%.
There are three different types of contacts between marmots. The locomotor contact is the most common, followed by acoustic and visual contact.
Hibernation
At the end of September and beginning of October, the period of summer activity ends for the Tatra marmot, and the hibernation period begins. Changes in the environment signal the marmot's organism. The air temperature drops, the days become shorter, and the vegetation, which serves as food, becomes scarce. Marmots curl up into a ball and collectively arrange themselves at the bottom of the winter burrow chamber. Metabolic processes slow down, allowing the body temperature to decrease from 37.7 °C to 8–10 °C, which is about 2–3 °C lower than the temperature inside the burrow. In exceptional situations, the body temperature may drop to 3–5 °C. Respiratory rate decreases from 16 to as low as 2–3 (or 4–5) breaths per minute, as oxygen consumption during hibernation decreases by about thirty times, and the heart rate decreases from 220 to 30 contractions per minute. Other sources specify the frequency of heart ventricular contractions in the summer period as 130, decreasing during hibernation to 15 per minute.
Young marmots usually hibernate in the middle of the family, enveloped by older individuals, which helps them survive the burden of winter sleep more easily. Adult marmots accumulate more fat for this period. They also maintain a slightly higher body temperature.
During hibernation, the marmot wakes up approximately every 3 weeks. The awakening lasts for about 12–30 hours, after which the animal returns to sleep. The trigger for awakening may be a decrease in the temperature inside the burrow to 0 °C. Too many awakenings during hibernation are very energetically costly for the marmot's organism. During these short awakenings, the marmot's body temperature rises to about 34 °C, sharply increasing energy expenditure, and up to 90% of the reserves accumulated in the form of brown adipose tissue are consumed. In the case of prolonged winter, the organism may become excessively depleted, leading to the death of the animal. During hibernation, the marmot's body mass significantly decreases. Hibernation lasts for 201–227 days, 215 on average.
Social structure
Family colony can consist of several individuals – the dominant pair, their offspring from different years, and adopted individuals. According to former director of Tatra National Park, , several marmot families can comprise a colony. Marmot territorialism manifests in the daily need for the dominant male to patrol the boundaries demonstratively, systematically marking the territory with its scent. This is most likely done through secretions from glands located in the anal region, cheek glands, and glands in the paw pads. The marked territory is defended by the male against individuals from neighboring colonies. The first warnings are visual signals. The male raises its fur and waves its tail vertically. If the warning is not enough, it leads to a fight, where decisive wounds are inflicted using incisors. If the fight is evenly matched and neither male surrenders or flees, the brawl can last even the whole day. Aggressive defense is mainly directed towards foreign adult males. Young individuals can visit even the center of a foreign colony without fear. They are seen as adoption candidates for the colony without posing a threat to the dominant male's position.
The social nature of marmot colonies is evident in their collective actions. They build burrows together, sleep together, and help each other groom. Young ones play together in groups, wrestling, standing in a "pillar" position, or chasing each other around the colony area. During a meeting, marmots greet each other by touching noses and sniffing. Sometimes, they also show excitement by moving their tails up and down. Reproduction is also subject to specific rules and is reserved only for the dominant pair. Mature individuals in the colony must adhere to the leader in this regard. Periodic battles for leadership may result in the overthrow of the dominant male. He is then expelled from the colony, and the victor may sometimes kill his offspring to solidify his power.
Sounds
Marmots also communicate with each other using whistles or rather screams, as the sound emanates from their wide-open mouths. Its primary function is to warn colony members of danger. Several different levels of alarm whistles can be distinguished. The presence of a human, dog, or fox is signaled by a series of moderately intense whistles – then marmots swiftly move to the nearest burrow and observe from its entrance how events unfold. The series of whistles usually also discourages a fox, who is aware that after hearing the alarm signals, no marmot will become its prey. The greatest threat, such as the appearance of an eagle, is signaled by a single sharp whistle. Then, marmots flee without hesitation and hide in their burrows.
Marmots also emit other sounds, which can be described as squeaks or murmurs. These do not convey warning information.
Geographical distribution
The range of the Marmota marmota species spans between 44° and 49° N. Natural populations have survived in two mountain ranges: the Alps and the Tatra Mountains. The Tatra Mountains represent the northern range of the species (49° 14" N). The Alps are inhabited by the subspecies Marmota marmota marmota, while Marmota marmota latirostris is an endemic species living in Poland and Slovakia. The vertical distribution range of Tatra marmots' habitats ranges from 1380 to 2050 meters above sea level, or according to other sources: in the Polish Tatra Mountains from 1750 to 1950 meters above sea level (with an average of 1870 meters above sea level), and in the entire Tatras massif from 1380 to 2330 meters above sea level.
In the main Tatra range, 207 main burrows were inventoried, and in the Low Tatras, 46 burrows were counted, or according to other sources, 40 burrows. The population of Tatra marmots on the Polish side of the Tatras was estimated at 150–200 individuals, while the total population in the entire Tatras is less than 1000 individuals.
The issue of precisely determining the locations of M. marmota latirostris in the Tatra Mountains encounters certain difficulties. While it is easy to establish that the autochthonous subspecies of the Tatra marmot occurs in the Western and Eastern Tatras, the origin of the marmots occurring in the Slovakian Low Tatras (with the highest peak being Ďumbier) separated from the main massif of the Tatras by the is not clear. Although Ludwik Zejszner claimed that marmots were already living in the area of Solisko and Ďumbier in 1845, some researchers believe that the population in the Low Tatras is introduced from other parts of the Tatras. The fact of the 19th-century introduction in the area of Kráľova hoľa in the eastern part of the Low Tatras is reported by many researchers. Some even specify a specific time frame for it, around 1859–1867. Others believe that the marmots from the western part of the Low Tatras constitute a post-glacial population because, in their opinion, marmots would not be able to penetrate through the forested areas of the central part of the Low Tatras from previous introductions. In 1961, an expert on Tatra fauna, zoologist from the research station of the national park, Milič Blahout, wrote directly about the introduction of marmots from the Austrian Alps released in the Low Tatras between 1859 and 1867. Barbara Chovancová, who leads the marmot and chamois protection program in the Slovak Tatra National Park (TANAP), has no doubts that introductions were carried out twice in the Ďumbier area of the Low Tatras. Alpine marmots were released there in 1859, and in 1867, two pairs of marmots from the High Tatras were also released. If this were indeed the case, hybridization between representatives of both marmot subspecies could have occurred. Slovak authors mention a possible gene exchange between populations from the western and eastern parts of the Low Tatras. However, most believe that only Marmota marmota latirostris inhabits the Low Tatras. Kratochvíl proposed a hypothesis regarding the potential historical introduction confusion. He pointed out that historical information about marmots in the Carpathians could refer to populations still living in the 19th century in the Carpathians in Romania and Ukrainian Zakarpattia. However, there is a lack of reliable cranial or genetic studies that would resolve the issue of the origin of the populations in the Slovak Low Tatras.
Data about historical locations of marmots in the Tatra Mountains was derived from extensive local nomenclature referring to marmot habitats: Svišťový štít, Svišťová dolina, Svišťovský potok, Świstówka Roztocka, Świstówka Waksmundzka, Malá Svišťovka, Veľká Svišťovka, Svišťové sedlo, Świstowa Grań with Svišťové veže included, Świstowa Rówień, Svišťové plieska, Svišťový roh, Svišťová kôpka, Svišťový priechod, Svišťový chrbát, Sedlo pod Svišťovkou, Svišťovka, Nižná svišťová jaskyňa, Vyšná svišťová jaskyňa. These names appear in literature only in the 17th century, but Gabriel Rzączyński already in 1721 mentioned, "is found in the Alps and Carpathian mountains in a valley named Świszcza" (probably referring to Svišťová dolina).
In the last decade, a small number of marmots from the population in the Slovak Tatras were introduced into the Ukrainian part of the Eastern Carpathians.
Fossil traces of occurrence
Fossil traces of marmot occurrence have been found in Moravia, and in Poland in the vicinity of Jasło.
Ecology
The Tatra marmot is a herbivore. The main components of its diet include: herbaceous vegetation, shrubs and prostrate shrubs, roots, and tubers. The composition of its diet changes with the periods of vegetation in the Tatra Mountains. Favorite spring dishes include grasses, and in summer, the marmot most willingly eats spotted gentian, Luzula alpinopilosa, alpine coltsfoot, alpine avens, Mutellina purpurea, and Poa granitica. More than 40 species of consumed plants are mentioned; among them are alpine bartsia, wood cranesbill, Oreochloa disticha, European blueberry, Veratrum lobelianum, Campanula alpina, , Ranunculus pseudomontanus, large white buttercup, alpine hawkweed, brown clover, colorful fescue, Valeriana sambucifolia, Valeriana tripteris, Thymus alpestris, Thymus pulcherrimus, Adenostyles alliariae, dandelions, Solidago alpestris, Doronicum austriacum, Doronicum clusii, golden cinquefoil, , bistort, alpine bistort, golden root, alpine pasqueflower, alpine sainfoin, Juncus trifidus, Rumex alpestris, wavy hair-grass, eyebright, Soldanella carpatica, alpine meadow-grass, narcissus anemone and round-headed rampion. An adult marmot consumes about 1.5 kg of food daily. Water requirements are met by consuming juicy plants.
The Tatra marmot is vulnerable to attacks from predators such as the golden eagle, gray wolf, Eurasian lynx, and red fox. The mere presence of humans also causes pressure and changes in behavior. In relation to humans, the marmot maintains a safe escape distance of several dozen to several hundred meters. In relation to predators, this distance is significantly extended and can be several hundred meters.
Habitat
The entire population of the Tatra marmot is located within the territory of the Slovak Tatra National Park (TANAP) and the Polish Tatra National Park, so the habitat has a primitive character.
The typical habitat of M. marmota latirostris consists of Tatran areas in the altitudinal zonation: alpine zone, subalpine zone (grassy fragments), mountain zone (open spaces), and to a limited extent, foothill zone, with an average annual temperature ranging from -3 to +3 °C. The marmot prefers sunny places. The slope angle of the mountain habitats does not exceed 40°. The marmot enjoys the surroundings of rocks, which provide a good observation point and can also serve as shelter for hiding. The soil must have sufficient thickness to allow the digging of a burrow.
In the Tatras, the upper limit of vertical distribution of habitats is determined by orographic conditions. Above 2300 m above sea level, the low thickness of the soil basically prevents the digging of burrows. The lowest recorded site was inventoried at an altitude of 1350 m above sea level.
The central part of the colony typically occupies an area of about 2.5 hectares. The surface area of the territory depends, of course, on the vegetation coverage and the size of the colony. However, most authors report much smaller surface areas occupied by the colony: Peter Bopp 2000–2500 m2, Josef Kratochvíl 7900 m2, Milíč Blahout 2500–3600 m2, Dymitr I. Bibikov 500–4500 m2. The maximum occupied area can reach 2–7 hectares.
Burrow
The burrow is the most important habitat for the marmot. It spends the entire period of hibernation in it, and during the summer, the burrow provides shelter. Therefore, suitable soil conditions, which allow easy excavation of tunnels, largely determine the location of a given colony. Both the thickness of the soil and the arrangement of aquifers are important, as they influence the avoidance of flooding or inundation. The nesting chamber is lined with dried grasses from the local vegetation. The marmot utilizes Juncus trifidus, Oreochloa disticha, fescue, reed grass, moss and lichens. The gathered lining is not used by marmots as food. It has also been observed that marmots collect tissues or fabrics discarded by tourists for this purpose. Marmots maintain cleanliness of their burrows, so each burrow is equipped with a latrine, which is created in alcoves along the side tunnels. Only there does the marmot relieve itself. Similarly, local marmot latrines can also be found outside formal burrows. They are created temporarily on the family's territory, in short tunnels, or in depressions under rocks.
Hibernation burrow
The hibernation burrow plays a crucial role in the life of these animals. A marmot family spends an average of 215 days per year in it, hence the term "main burrow". It can also serve as the center of a marmot's life. The winter burrow consists of an entire system of branching tunnels, which can have a total length of over 10 meters. The tunnels have an oval shape with a diameter of 15–18 cm and are relatively shallow, but below the frost line – typically 1.2 meters below ground level. The central chamber of the burrow is located even up to 7 meters deep, accessed by several tunnels allowing the use of distant entrances. The chamber is abundantly lined with hay collected by the animals. To prepare one bedroom for winter, these rodents can use up to 15 kg of grass. Near the entrances, there is usually an earth mound formed by the removal of material during tunneling. The tunnels are equipped with small widenings, which allow family members to pass each other going in opposite directions. Before winter, the entrances to the burrows are carefully sealed by the marmots from the inside with packed earth, stones, and feces.
Each burrow houses a family hibernating, usually consisting of 4 to 10 marmots. In the past, accounts from hunters indicated that they found between 2 and 15 individuals dug out from a winter burrow.
Summer burrow
The summer burrow, sometimes referred to as transitional, is a system of tunnels built for temporary use during the summer season. It is excavated more shallowly (does not need to protect from the cold of frozen ground) and has a shorter tunnel system. Sometimes, after summer, it may be deepened and used for hibernation. However, if a family uses the hibernation burrow in the summer, they do not build a separate summer burrow.
Escape burrow
The most commonly encountered underground structure of the marmot is the escape burrow, also known as emergency or rescue burrow. These are makeshift shelters from predators. Their construction is very simple – sometimes their length does not exceed 1 meter, and they are equipped with only one or two entrances and do not have many branches. The marmot tries to cover its territory with a network of such makeshift shelters. Within the area of one colony, there can be found from 16 to 20 such hiding places, and when disturbed, the animal can remain underground for several hours. The marmot tries not to stray more than 10–15 meters from the nearest shelter. Over time, even escape burrows can be expanded and elevated to a higher status.
Tatra marmot in captivity
Tatra marmots are not currently bred in Polish zoos. Between 1924 and 1935, the zoo in Poznań possessed three individuals from the Polish population of M. marmota, while from 1927 onwards, the Kraków Bażantarnia (which was succeeded by the local zoo) bred four Tatra marmots. After World War II, individual specimens of this subspecies were exhibited in Czechoslovakian zoos.
Threats and conservation
Legal conservation
International law
Bern Convention – annex III
Habitats Directive – annex II and IV
National law
Species protection in Poland – strict protection
Threat categories
– EN
– EN
Carpathian List – EN (in Poland – CR)
IUCN classification: Marmota marmota marmota is abundant, least concerning (LC). The subspecies Marmota marmota latirostris is rare and requires strict protection. Highly endangered in Poland due to a small population.
Threats
Until the 19th century, regular hunting of marmots was conducted in the Tatra Mountains, where their skins, meat, and fat were highly sought-after commodities. There was a particularly high demand for marmot fat due to its use in traditional medicine and the widespread belief in its miraculous healing properties. Marmot fat was used both externally and internally for various purposes, including the treatment of hernias. It was also given with milk to women in labor to facilitate childbirth and as a strengthener. Additionally, it was believed to heal wounds, treat swollen glands (lymph nodes), and alleviate coughs. Towards the end of the 19th century, when Zakopane gained status of a spa town, many tuberculosis patients sought "miraculous remedies" in the form of marmot fat.
Marmot skins were used to cover horse collars or sold as fur to urban residents. However, the highlanders in the Podhale region did not use them to make their own clothing. Freshly removed marmot skins were applied to painful areas for rheumatism. Marmot meat was also considered the best among all game meats.
In the second half of the 19th century, only refuges inaccessible to hunters remained. In 1881, only 30 individuals were inventoried on the Polish side of the Tatras, and by 1888, there were 35 individuals left.
On 5 October 1868, under pressure from members of the local history commission of the (Maksymilian Nowicki, Ludwik Zejszner, and Father Dr. ), the Diet of Galicia and Lodomeria in Lviv adopted a law regarding the prohibition of capturing, exterminating, and selling alpine animals proper to the Tatras, marmots, and wild goats. This was the world's first case of parliamentary enactment of a law protecting animal species. The situation of the Tatra marmot worsened again during World War I, leading to an increase in hunting. Since then, sheep grazing in marmot habitats has also begun. A significant improvement in the situation came with the establishment of the Tatra National Park in 1954, which encompasses all marmot locations in the Polish Tatras.
The main threats to M. marmota latirostris include pressure from predators and hunting. Changes in behavior are induced by excessive tourist and sports activity. Human presence also limits contacts between colonies (e.g., in the Kasprowy Wierch area), which are necessary for genetic exchange, and increases the risk of additional diseases, including parasites.
Population
Since the significant decline of marmots in the 19th century, their population has slowly been increasing. In 1881, there were 30 marmots in the Polish Tatras, between 1888 – 35, in 1928 and 1952 – 50, in 1982 between 108 and 132, and around 190 individuals in 2003. Altogether, on both sides of the Tatras at the beginning of the 21st century, there were approximately 700–800 individuals of this subspecies.
See also
List of mammals of Poland
Fauna of Poland
References
Marmots
Tatra Mountains
Rodents of Europe
Herbivorous animals
Endangered species
Critically endangered animals | Tatra marmot | [
"Biology"
] | 6,974 | [
"Biota by conservation status",
"Endangered species"
] |
76,459,830 | https://en.wikipedia.org/wiki/Entoloma%20ferruginans | Entoloma ferruginans is an endemic mushroom of California in North America. It smells distinctly like a chlorinated pool at the YMCA, thus the common name bleachy entoloma. E. ferruginans lives in mycorrhizal association with live oaks south of the San Francisco Bay. This mushroom was first described by Charles Horton Peck in 1895 from a type specimen collected under oak trees in Pasadena.
References
Sources
Fungi of California
Fungus species
Taxa named by Charles Horton Peck
Fungi described in 1895
Entolomataceae
Mycorrhizal associates of oaks | Entoloma ferruginans | [
"Biology"
] | 123 | [
"Fungus stubs",
"Fungi",
"Fungus species"
] |
64,746,443 | https://en.wikipedia.org/wiki/Oneirodes%20sanjeevani | Oneirodes sanjeevani is a species of marine ray-finned fish belonging to the family Oneirodidae, the dreamers, a family of deep sea anglerfishes known by a single specimen which was described in March 2017. The holotype was recovered by midwater trawling in the Indian Ocean west of the Maldives at 00.87°S, 67.59°E from a depth between 380 and 600 meters. The holotype, a female, has a standard length of , with 5 soft rays in its dorsal fin and 4 in its anal fin. It is named in honor of Dr. V. N. Sanjeevan, who was the Director of the Centre for Marine Living Resources & Ecology in Kochi, Kerala, southern India.
References
sanjeevani
Deep sea fish
Fish described in 2017
Fish of the Indian Ocean
Species known from a single specimen | Oneirodes sanjeevani | [
"Biology"
] | 181 | [
"Individual organisms",
"Species known from a single specimen"
] |
64,747,458 | https://en.wikipedia.org/wiki/WASP-46 | WASP-46 is a G-type main-sequence star about away. The star is older than the Sun and is strongly depleted in heavy elements compared to the Sun, having just 45% of the solar abundance. Despite its advanced age, the star is rotating rapidly, being spun up by the tides raised by a giant planet on a close orbit.
The star displays an excess ultraviolet emission associated with starspot activity, and is suspected to be surrounded by a dust and debris disk.
Planetary system
In 2011 a transiting hot superjovian planet, WASP-46b, was detected. The planet's equilibrium temperature is . The dayside temperature measured in 2014 is much higher at , indicating a very poor heat redistribution across the planet. A re-measurement of the dayside planetary temperature in 2020 resulted in a lower value of 1870 K.
In 2017, a search for transit-timing variations of WASP-46b yielded zero results, thus ruling out existence of additional gas giants in the system. The orbital decay of WASP-46b was also not detected.
References
Indus (constellation)
G-type main-sequence stars
Planetary systems with one confirmed planet
Planetary transit variables
J21145687-5552184
101
231663901
46 | WASP-46 | [
"Astronomy"
] | 252 | [
"Constellations",
"Indus (constellation)",
"Astronomy organizations",
"Wide Angle Search for Planets"
] |
64,748,079 | https://en.wikipedia.org/wiki/Matibabu%20%28Rapid%20Malaria%20test%29 | matibabu fights to close the gap between the communities and their rightful access to healthcare.
Purpose and Use
In general, the lack of low cost diagnostics for malaria results in late diagnosis of the disease in many low income communities (contributing to high morbidity and mortality from severe forms of malaria), and over-treatment of malaria where syndromic management is used due to lack of point-of-care diagnostics (contributing to wastage of money on treatment of non-malarial illness especially since the new recommended Artemisinin-based therapies are expensive). Additionally, Inconsistent data relay to the Ministry of Health despite the fact that there are a number of data management platforms being used by health practitioners. The data received is inconsistent in terms of both quality and quantity and is often outdated or not in realtime. The current data collection and surveillance methods are through the national Health Management Information System (HMIS). Data is first collected at the health centre level where hard copies(paper/books) are used and electronic medical record systems for a few health centers that have the capacity. However there is very low usage of this system as paper-based records are lost in delivery, poor quality of data(inaccurate statistical data), untimely delivery of HMIS reports, exclusion of data from the private health providers and at the community level, inadequate segregation of HMIS data and limited political support. Lack of functional supply chains and adequate reporting around availability of supplies, means that often health facilities are without vital drugs and equipment for long periods of time and as a result drug and diagnostic performance can not be monitored.Efficient health information and data systems are vital for improved decision making and timely intervention. We are shifting into an era where data driven approaches have yielded appropriate resource utilization for implementing health programs.
The device is capable of detecting malaria parasites in red blood cells for diagnostic purposes. The device is being tested for use in hospitals, clinics and medical laboratories. The goal is to create Point-of-care-testing (POCT) opportunities in rural areas that lack healthcare access.
Invention
The company offers an array of solutions as listed below;
Matiscope: The matiscope is a portable parasite-based hardware device that uses principles of light scattering and magnetism to detect Plasmodium in blood samples. The kit offers both invasive and non-invasive diagnosis with desktop point of care.
Yotta: captures data, such as location data and health survey information, anonymized data points in a securely managed central data store, and includes both automated and expert data analysis, and customized outputs and feedback that lead to timely and targeted responses. The data visualisation also enables us to run prediction algorithms on the data to deduce geographically customized disease trends.
Yotta cards: Patient tracking to support the health facilities manage & track medication issued, schedule routine visits & also patients saving on the card for health care access topped up with loans
Yotta surveillance apps: Powered with image recognition algorithms, the application is used at the health facility to collect the disease data in almost real time, with both offline and online capabilities.
The device was invented in Kampala, Uganda by Matibabu CEO Brian Gitta and his team (Joshua Businge, Josiah Kavuma, Moris Atwine, Simon Lubambo and Shafik Sekitto).
Recognition
The team at matibabu, have realized Villgro Kenya, Bayer Foundation, e4impact, Merck Accelerator and the Resilient Africa Network(RAN) operating under The United States Agency for International Development.
matibabu has also been recognized on several occasions as the UN Empowerment Award through the Microsoft Imagine Cup, American Society for Mechanical Engineers’ iShow, The Duke of York’s Pitch@Palace, Royal Academy of Engineering The Aspirin Social Innovation Award, e4Impact, Disrupt 100, Time magazine Next Generation Leaders, 2019 Rolex Laureate and additionally, we have showcased at different platforms as the Consumer Electronics Show (CES), The Tech Open Air Festival, Republica, Global Sankalp forum, TechCrunch Hardware Battlefield. Brian Gitta was further invited to meet Bill Gates as part of the MTV Base Africa program in 2016.
Advisors
Matibabu was part of the Merck Accelerator Program at the Merck Innovation Center in Darmstadt, Germany.
The advisors of Matibabu include Dr. Nicole Kilian (Heidelberg University Hospital), Robert Karanja, MSc (Villgro Kenya) and Kush Mahan, MSc (ZoneIn).
References
Medical devices
Medical tests | Matibabu (Rapid Malaria test) | [
"Biology"
] | 929 | [
"Medical devices",
"Medical technology"
] |
64,750,192 | https://en.wikipedia.org/wiki/Pulvino | A pulvino (or impost block) is an architectural structural element (dosseret) having the shape of an inverted pyramid cushion, which is placed between the column capital and the arch base.
Overview
Usually decorated with fretwork or relief ornamental motifs, the pulvino reaches its maximum expression in the Byzantine architecture; some examples can be found in the early Christian architecture of Ravenna. Its particular convex shape gives the pulvino the structural function of concentrating the tensions generated by the loads above it and passing the tensions on the column located below the capital. An example can be seen in the church of San Lorenzo in Florence designed by Filippo Brunelleschi around 1420. There he resorted to additional segments of entablature improperly defined as "Brunelleschian nut". The pulvino in this case created a balanced entablature, on which the round arches are set.
Modern engineering
By analogy with the static function of the pulvino on a column, it is also attributed to certain structural elements that have the function of distributing a load from a superimposed structure with higher mechanical resistance characteristics, to a lower structure with lower specific resistance and, therefore, dimensioned in such a way as to reduce the unitary stresses to admissible values.
In contemporary engineering, the pulvino is used as a structural element to distribute the load between an overlying part with less mechanical resistance and an underlying part with higher resistance. For example, it is used in railways to transfer the load of rails onto sleepers. Generally, it is made of cast iron.
Gallery
See also
Abacus
Capital
Impost
Waterleaf
References
Architectural elements
Columns and entablature | Pulvino | [
"Technology",
"Engineering"
] | 343 | [
"Building engineering",
"Structural system",
"Architectural elements",
"Columns and entablature",
"Components",
"Architecture"
] |
64,751,159 | https://en.wikipedia.org/wiki/Temporal%20clause%20%28Latin%29 | A temporal clause is an adverbial clause of time, that is to say, a clause which informs the reader about the time when the action of main verb of the sentence occurred. So in a sentence such as "after I had said this, he went out", the first clause is a temporal clause. The name comes from the Latin word , genitive , 'time".
Typically in Latin a temporal clause has a conjunction of time such as "when" or "after" at or near the beginning of the clause and a verb at the end. The verb in a Latin temporal clause is usually in the indicative mood, although sometimes, especially when the conjunction is , it is in the subjunctive. But if the clause is part of indirect speech, the verb is nearly always in the subjunctive mood.
The conjunctions used to introduce temporal clauses sometimes have other, non-temporal, meanings. For example, can mean "when", "since", or "although"; can mean "while", "until", or "provided that"; can mean "when" or "where", and so on.
Another possibility commonly used in Latin for expressing time is a participial phrase. For example, the temporal clauses (Nepos) "after he heard this" and (Cicero) "when he heard this" both mean much the same thing as the participial phrase (Pliny) (literally, "with which heard").
Temporal clauses are very frequent in certain styles of Latin such as history, and it is not uncommon to find a sentence introduced by two or three temporal clauses, often mixed with participial phrases of time.
Classification of temporal clauses
A common way of classifying temporal clauses is according to whether the action or situation described in the temporal clause is antecedent, contemporaneous, or subsequent to that of the main verb:
A. The action of the temporal clause verb is antecedent to that of the main verb:
The temporal clause describes an event completed before the main verb:
e.g. "after the signal was given, they began fighting"
The temporal clause describes a situation which began before the main verb and which may overlap with it:
e.g. "once the soldiers were in position, the generals came forward"
B. The action of the temporal clause verb is contemporaneous with the main verb:
Two events co-occur:
e.g. "when he fell, he was hurt"
Two situations are co-extensive:
e.g. "he was happy as long as he lived"
The main clause event occurs during the temporal clause situation:
e.g. "they arrived while he was sleeping"
The temporal clause event occurs during the main clause situation:
e.g. "when they arrived he was sleeping"
The main clause situation is interrupted by a temporal clause event
e.g. "he was sleeping, when suddenly they arrived"
The temporal clause defines the start-point of a situation:
e.g. "he had lived there since he was born"
The temporal clause defines the end-point of a situation:
e.g. "he lived there until he died"
C. The action of the temporal clause is subsequent to that of the main verb:
The temporal clause event happened:
e.g. "he left before I arrived"
The temporal clause event did not happen:
e.g. "he left before I had a chance to speak"
A second way of classifying temporal clauses is whether the sentence refers to a definite time, as in the above examples, or is iterative, describing a generalisation or repeated action at an indefinite time:
e.g. "whenever they win, they make a sacrifice"
A third classification is whether the main verb and hence the sentence as a whole is situated in past, present, or future time.
A fourth method of classification, followed in this article, is according to the different conjunctions used.
Choice of conjunction
Roman authors differ from one another in style, and this is shown among other things by their preference for different conjunctions. The table below shows the number of temporal clauses for some of the most common conjunctions in three historians of the republican period, Julius Caesar, Cornelius Nepos, and Sallust, and two poets of the following generation, Virgil and Ovid. The conjunctions are "when, while", "after", "when", "as, as soon as, when", "as soon as". The figures for and are included with and .
The figures for here are for clauses of time only, omitting causal or concessive ones.
The table shows that the narrative with the subjunctive is very common in Caesar and Nepos, but little used by the other three authors. Sallust used more than any other of the conjunctions, but it was avoided by Nepos. Conversely, Nepos and the two poets make frequent use of , but it is never used by Sallust. Caesar made relatively little use of compared with the other authors.
The following table shows the relative use of and "after" and and "before":
From this table it can be seen that Cicero had a clear preference for , while the other authors preferred . The conjunction is more common than in Cicero, and was used to an extent by Livy, but is almost completely avoided by Caesar, Nepos, and Sallust.
The conjunctions and , both meaning "until" or "as long as", also show variation. occurs 144 times in Cicero but only twice in Tacitus. It is rare in poetry, occurring once in Horace and twice in Lucretius only. Conversely, is hardly found at all in writers of the republican period, but became popular under the empire; in Tacitus it occurs 140 times.
Tense and mood
The tense and mood of the verb used in a temporal clause can affect the meaning. For example, (pluperfect subjunctive) means "after he came", but (pluperfect indicative) means "whenever he came". Or again, (present indicative) means "while he was coming", but (imperfect subjunctive) means "until he came".
The tense and mood used in a temporal clause may also vary with the conjunction: ("after he heard") uses the perfect indicative, but ("when he had heard") uses the pluperfect subjunctive, although the meaning is very similar or identical. In a past context, the conjunctions , , , and tend to use the perfect or imperfect indicative, whereas is usually followed by the imperfect or pluperfect subjunctive.
Over the three centuries between 200 BC and 100 AD, the use of the subjunctive in temporal clauses became more common. The conjunction mostly has the indicative in Plautus, but in Caesar the majority of clauses have the subjunctive. Iterative clauses (that is, those meaning "whenever...") usually have the indicative in Caesar and Cicero, but from Livy onwards the subjunctive became usual. A similar increased use of the subjunctive can be seen in clauses containing "while / until" and "before".
On the whole, temporal clauses use the indicative mood except, unless they are in indirect speech. The main exceptions are the common use of cum with the imperfect or pluperfect subjunctive, and clauses of the type "before X could happen" or "until such time as X might happen" which anticipate some future event.
One difference from English grammar is that in temporal clauses referring to the future (e.g. "when you receive this, write back"), the future or future perfect tense is usually used in Latin where English uses the present. Thus the Latin equivalent is "when you will have received this, write back". In such sentences, if the main verb is an imperative, the future imperative (e.g. "write (at that time)") is used. The same tenses are used with conditional sentences starting with "if":
ubi nihil erit quod scrībās, id ipsum scrībitō (Cicero)
"when there is (lit. "will be") nothing to write about, write that fact itself"
sī quid acciderit ... scrībitō (Cicero)
"if anything happens (lit. "will have happened"), write"
Word order
A temporal clause can come before the main clause, after it, or in the middle. It is also possible, in the case of separated , for the main verb to be placed in the middle of the conjunction. In the majority of cases, however, temporal clauses precede the clauses which they modify. This is because the main information which the speaker wishes to communicate, or "focus" of the sentence, tends to be placed second. But if the main information is in the temporal clause (as with clauses), they come after the main clause.
Quite frequently a topic word precedes the temporal clause conjunction. The topic word sometimes comes from the temporal clause itself, for example and in the following sentences:
(Cicero)
"when I got there, the governor was taking a siesta"
(Caesar)
"when they saw this, they changed their plan"
In other sentences the topic word comes from the main clause, such as in the example below:
(Cicero)
"As for Balbus, I haven't seen him since you left"
Sometimes several topic words can precede the temporal clause, as in the following:
(Cicero)
"when Caesar saw him there, he didn't say anything harsh or unkind"
The verb in the temporal clause usually comes at the end of the clause, although as the examples below show, there are occasional exceptions.
Different conjunctions
The most commonly used conjunction in temporal clauses is ; an older spelling was , showing its derivation from the relative pronoun . The usual meaning is "when", but it can also mean "since/in view of the fact that" or "although/despite the fact that" (concessive ). These meanings can overlap to an extent.
Grammarians usually divide the meanings into two classes: the purely temporal , which takes an indicative mood verb, and the circumstantial , which takes the subjunctive mood. The circumstantial is divided into historical, causal, and concessive uses.
In the early Latin of Plautus, both types of were followed by the indicative mood; however, in the classical period, whenever the meaning is causal or concessive, is always followed by the subjunctive mood. When the meaning is purely of time, in a present or future context, the indicative is usual; in a past context, in the classical period, both subjunctive and indicative are used, but the subjunctive is much more common.
When has the subjunctive mood, it usually expresses a fact of secondary importance. In such clauses 'the mind of the writer seems always fixed on something farther on, which is of more importance to him". This is known as "circumstantial ".
Historic
One of the most common uses of , often found in historical writing, is with the imperfect or pluperfect subjunctive, giving the circumstances in which an action took place. This is known as the "historic" or "narrative" use of .
When the tense is imperfect subjunctive, it usually describes a situation already happening when the main action took place. A common way of translating it is "while":
(Cicero)
"while I was sitting sadly at home, Venerius suddenly came running up"
(Caesar)
"while the ship was approaching the city, the whole population poured out to find out the news"
(Gellius)
"when by chance he was making a journey alone, he saw an oak-tree near the road"
With the pluperfect subjunctive, it usually means "after X had happened":
(Livy)
"after Antiochus had left Egypt, the ambassadors sailed to Cyprus"
(Caesar)
"after he had said this in a loud voice, he flung himself out of the ship"
(Cicero)
"after Crassus had said these words, a silence followed"
Imperfect indicative in the main clause
Normally the verb in the main clause after a historic -clause will be either historic present or perfect indicative. However, sometimes the main verb is in the imperfect tense, in which case it describes a situation rather than an event. In the following sentences, the main verb does not describe a pre-existing situation, but a situation which began after the action of the temporal clause:
(Caesar)
"after he arrived there, he was in great difficulty as to how he could reach the army"
(Caesar)
"after Caesar arrived in Asia, he began hearing reports that Titus Ampius had been trying to steal money from the temple of Diana in Ephesus"
The following sentence, however, is ambiguous. Some translators interpret it to mean that the situation had already begun when Caesar arrived:
(Caesar)
"upon his arrival there, he found five cohorts, whom Domitius had detached from the garrison, employed in breaking down a bridge about three miles distant from the town"
An alternative interpretation is that the cohorts began breaking up the bridge after Caesar arrived. In the following sentence, which has and the pluperfect, the situation is definitely already under way:
(Nepos)
"for by the time he got there, Agesilaus had already stormed many places and gained possession of a large amount of booty"
When both verbs are imperfect, the situations overlap in time:
(Caesar)
"while they were retreating into the camp, they kept meeting the enemy who were coming towards them"
Causal
Frequently, the meaning "when" shades into "since" and gives the cause of the action of the main verb. In some sentences, either interpretation (causal or temporal) is possible, while in others "seeing that" or "since" or "in view of the fact that" is better:
(Caesar)
"at this point there was fighting for a short time, while/since our men were trying break into the camp, and the others were defending it"
(Caesar)
"Lucius Petrosidius the eagle-bearer, when/since he was being pressed by a great multitude of enemies, hurled his eagle inside the camp wall"
(Caesar)
"the Haedui, since they were unable to defend themselves and their property from them, sent envoys to Caesar to ask for help"
(Caesar)
"since there was a plain between the two camps, Domitius arranged his battle line near Scipio's camp"
When is causal, it always takes the subjunctive even if it refers to present time:
(Cicero)
"in view of the fact that these things are so" / "since this is so"
Concessive
Another, less common, meaning is 'though" or "despite the fact that". The subjunctive is always used:
(Cicero)
"he did nothing to help me, though (or: at a time when) he could have done"
(Caesar)
"in this whole battle, though the fight went on from the seventh hour to evening, no one could see the enemy turn their back"
The use of the subjunctive with the concessive meaning of is found even in very early Latin:
(Naevius)
"by God, Cupid, although you're so small, you are too powerful!"
Adversative
Another category of clause argued for by some grammarians is known as "adversative", in which two situations are contrasted:
(Caesar)
"but the enemy, as soon as they caught sight of our cavalrymen, of whom the number was 5000, while they themselves had not more than 800 cavalrymen..."
Generic
Just as the relative pronoun followed by the subjunctive can have a generic meaning ("the sort of person who..."), so can also be generic (i.e. "at such a time as..."). In the following sentence the verb after is imperfect subjunctive:
(Cicero)
"for he received the farm at one of those times when the prices of estates were low"
In the following, situated in future time, it is present subjunctive:
(Cicero)
"I'm sure there will come a time when you will desire the services of a great friend"
"Heard someone saying"
In Latin, "I heard him saying" can be expressed as "I heard him while he was saying" (or: "I heard from him while he was saying"), using a clause with the subjunctive. This turn of phrase is used several times by Cicero:
(Cicero)
"I heard Metrodorus discussing these very matters"
(Cicero)
"I have often heard him say that he was not accustomed or able to write them down"
It is also possible to use an accusative and infinitive to express this meaning:
(Gellius)
"I once heard Valerius Probus say this"
Another way is to use a present participle:
(Gellius)
I once heard Herodes Atticus giving a lecture in Greek in Athens"
with the indicative
Used with the indicative mood, the conjunction can mean "at that time when". This is known as 'temporal ".
In the examples below, the events occur at exactly the same time, and the subjunctive could not be used:
(Cicero)
"when they are silent, (it is as if) they are shouting"
(Cicero)
"he was dislodged from his vantage point, (at that moment) when he was driven out of the city"
Clauses like the above are sometimes known as "clauses of equivalent action", since the action of the temporal clause is equivalent to the action of the main clause. The same grammar is used for other actions which occurred at an identical time:
(Cicero)
"when Sextus Roscius was murdered, they were also there"
(Cicero)
"surely it is with this (rod) that Romulus marked out the regions of the sky at that time when he founded the city"
In the following, the verbs describe situations which occurred co-extensively and simultaneously. The main verb is perfect indicative, the temporal clause verb is imperfect indicative:
(Terence)
"thirty days, or more than that, I was in the ship, while all the time I was miserably expecting death"
The following has perfect in the temporal clause, and the imperfect in the main clause:
(Sallust)
"at that time when Sulla ordered Damasippus and others to be put to death, who was not praising his action?"
In the following, both clauses have the imperfect indicative tense:
(Cicero)
"the Decii could see the flashing swords of the enemy, at the same time as they were rushing upon their battleline"
(Cicero)
"I could see it then, when you were speaking"
The following has with the imperfect indicative, but the perfect indicative in the main clause:
(Cicero)
"right at the end, just when the defendant was already leaving the province, Carpinatius sent letters to them..."
In other sentences, however, the clause seems more circumstantial:
(Cicero)
"I told Gallus, last time I was in Rome, what I had heard"
(Cicero)
"I was overcome with greatest joy when I heard that you had been made consul"
The following examples, where the context is similar, have with the subjunctive:
(Cicero)
"concerning which we had a discussion recently when I was in my villa at Tusculum"
(Cicero)
"when he heard about his own son, he was heart-broken"
Temporal with main clause imperfect
In the following examples, the temporal clause describes an event, while the main clause describes a situation which already existed at the time. The temporal clause verb is perfect or historic present indicative, the main clause verb is imperfect indicative:
(Caesar)
"(at that time) when Caesar came into Gaul, the leaders of one faction were the Aedui, of the other, the Sequani"
(Cicero)
"when I got there, the governor was taking a nap"
The phrase "there was a time when" can be followed by indicative or subjunctive; but the subjunctive is more common. The following example has the imperfect indicative:
(Cicero)
"there was a certain time when people used to roam around randomly in the countryside like wild animals"
While the following has imperfect subjunctive:
(Caesar)
"there was formerly a time when it was the Gauls who were superior to the Germans in fighting spirit"
of time how long
Another idiom using is the following, indicating how long a certain situation has persisted. The verb in both clauses is present indicative:
(Cicero)
"he has owed me money for many years"
(Cicero)
"amongst the Greeks it is now nearly 500 years that this has been approved of"
(Gellius)
"we have been searching for it for a long time now"
The length of time can also be expressed using an ordinal number:
(Cicero)
"it is the twentieth year now that they have been attacking me"
In such sentences the clause can also have the perfect tense, as in the following example:
(Cicero)
"it is not yet a hundred and ten years since the law on extortion was passed"
(Plautus)
"it's less than 15 days since you received 40 minae from Callicles in front of this house"
The following example shows the same type of clause situated in past time, and uses the imperfect indicative and pluperfect indicative tenses:
(Livy)
"for many years there had been no disputes between the patrician magistrates and the tribunes"
However, the length of time that a situation has gone on can also be expressed without using a clause. The main verb is present indicative:
(Cicero)
"he has been living in Lilybaeum for many years now"
(Cicero)
"for a long time now I've had no idea what you are doing, as you don't write anything"
Iterative
Clauses which refer to no definite occasion, but to generalised or repeated actions ("whenever..."), usually use the indicative mood; although from Livy onwards the subjunctive mood could also be used.
In present or indefinite time, if the two events are simultaneous, the present tense is used in both:
(Caesar)
"they fight almost daily battles with the Germans, whenever they are either keeping them out of their own territory, or themselves fighting in the Germans" territory"
(Caesar)
"these, whenever there is need, all take part in the war"
(Cicero)
"the sort of things which no one dares to tell me when(ever) I'm in Rome"
However, if the temporal clause event precedes the main clause event, the perfect indicative tense is used in the temporal clause:
(Caesar)
"whenever they win (lit. "have won") a battle, they sacrifice the captured animals"
(Caesar)
"the Britons call it a "town", whenever they have fortified some dense woodland with a rampart and ditch"
In a past context, if the events are contemporaneous, the imperfect indicative is used in both clauses:
(Cicero)
"personally, whenever I used to be praised by our friend Cato, I didn't at all mind (lit. "I was easily suffering") being criticised by other people"
But if one event is earlier than the other, the temporal clause has the pluperfect indicative, while the main clause is imperfect:
(Caesar)
"whenever any cohort left the circle and made an attack, the enemy would retreat very quickly"
(Cicero)
"it was only when he saw (lit. "had seen") a rose that he used to reckon that spring was beginning"
In authors from the time of Livy onwards, however, the subjunctive is sometimes used in iterative clauses:
(Livy)
"whenever they saw (lit. "had seen") a debtor being led to court, they used to flock together from all sides"
in a future context
A similar construction is also used in clauses referring to the future, whether or not they are iterative. In future sentences, where English uses a present tense in the temporal clause, the Latin idiom is to use the future tense in both clauses:
(Cicero)
"I will let you know when (whenever) I have (lit. "will have") some news"
(Cicero)
"I would like you to write me your plans as soon as you are able (lit. "will be able")"
But the future perfect indicative is used if the event in the temporal clause precedes the main event, as in the famous poem of Catullus describing the number of kisses he will ask for from his mistress Lesbia:
(Catullus)
"then, after we have made (lit. "will have made") many thousands, we will muddle up the accounts"
(Cicero)
"I'll write you a longer letter when I've got (lit. "will have got") more free time"
Inverted clause ()
In some sentences the circumstances are given in the main clause, while the main event is in the clause, which always comes second. This is known as "" or an inverted clause: Here is followed by a perfect or historic present indicative:
(Livy)
"Hannibal was already approaching the walls, when the Romans suddenly sallied out against him"
(Caesar)
"they were already preparing to do this at night, when some married women suddenly ran out into the streets"
(Virgil)
"scarcely had he spoken these words when suddenly the cloud which had been poured around them parted"
It has been argued that the kind of temporal clause is an innovation of Latin, not found in other early Indo-European languages. In this type of sentence, there is typically an adverb such as "by now", "scarcely", or "just" in the main clause, and often a word such as or "suddenly" in the -clause, as in the above examples.
The phrase means "as soon as" and it usually takes the indicative mood, just like or . The following example has the perfect indicative:
(Caesar)
"as soon as he was able, he hurried to join the army"
Sometimes, however, it takes a subjunctive verb, like the ordinary historic . The verb below is imperfect subjunctive:
(Caesar)
"as soon as there was beginning to be a sufficient supply of fodder, he came to the army"
The subjunctive is also used if the clause is part of indirect speech. In the following sentence both verbs are in the historic present tense, the first one subjunctive:
(Caesar)
"he ordered him to set out for the Veneti as soon as he could"
Another meaning, also with the indicative, is "at that time when first":
(Petronius)
"is she younger than I was when I first slept with a man?"
(Petronius)
"oh, if only we had those lions which I found here when I first came from Asia!"
"I remember when"
A temporal clause can be used after "I remember":
(Ovid)
"but I remember when that fame was mine!"
(Cicero)
"I remember the time when you used to seem to me to be lacking in common sense"
can also be followed by an accusative and infinitive construction, combined with a temporal clause:
(Seneca the Elder)
"I remember that he made a long eloquent speech on that occasion when he was led from the prison into the senate"
Alternatively, can take an accusative and infinitive accompanied by a circumstantial clause with the subjunctive:
(Cicero)
"I remember that on one occasion when my father was consul in Macedonia and we were in the camp, our army was disturbed by superstition and fear"
(Seneca the Elder)
"I remember going into his school at a time when he was just about to recite a speech against Milo"
The present infinitive () is used in these last two examples, since the reminiscence is a personal one.
The indicative is used when the clause is more definite ("I remember that time when..."), while the subjunctive is less definite ("I remember a time when" or "I remember one of the times when...").
The combination sometimes introduces a temporal clause, but more often means "both ... and" or "not only ... but also" or "just as ... so also":
(Caesar)
"Luck is an important factor in warfare, just as it is in all other matters"
With the perfect indicative
Another very common temporal conjunction is (less commonly or , mainly in Cicero) "after". The most common use is when one event followed another, in which case is usually followed by the perfect indicative:
(Caesar)
"after Caesar arrived there, he demanded hostages"
(Cicero)
"after I'd read your letter, your Postumia came to see me"
(Cicero)
"when he found this out, he was furious"
Time interval mentioned
The usual tense used with is the perfect indicative, when the length of time is given the tense is usually pluperfect:
(Nepos)
"Hamilcar was killed in the ninth year after he came to Spain."
(Curtius)
"on the thirtieth day after he had set out from Persepolis, he returned to the same place"
Sometimes and are separated, and the time is put into the accusative case:
(Cicero)
"the business was accomplished on the third day after he had spoken"
Rarely, alone stands for :
(Suetonius)
"he returned to Rome in the sixth month after he had set off"
(Cicero)
"on the day after these things were done"
Main verb imperfect
Sometimes the main clause following a clause is in the imperfect tense. In this case it does not represent a pre-existing situation, but a situation which began or which kept happening after the event in the clause:
(Livy)
"after the rout turned in this direction, some of them, shamelessly throwing off their armour, began rushing blindly into the water"
(Caesar)
"after the Gauls approached nearer, they kept falling into the trenches and getting impaled"
with the imperfect
Sometimes is followed by an imperfect indicative tense. In this case the temporal clause describes not an event, but a situation which overlaps in time with the action of the main clause, as in the first example below:
(Livy)
"once the soldiers on both sides were standing drawn up for battle, the generals, with a few of the nobles, came forward into the middle"
Such clauses often imply a spectator ("after he saw that...", "when it became clear that..."); they can also be considered "quasi-causal" ("in view of the fact that..."):
(Livy)
"in view of the fact that (or "after it became clear that") there was no hope of capturing the camp, he gave the signal to retreat"
(Cicero)
"after (you saw that) those who were your friends were unable to win, you made sure that those who were winning would be your friends"
A situation in the temporal clause can also be expressed using a pluperfect tense:
(Livy)
"when (it became clear that) open force had not been successful, the following day they surrounded the defences"
"Since the time when"
The conjunction or can also mean "since". In this case the temporal clause describes how long the situation has been going on. When the main verb is negative, the perfect tense is used in the main clause:
(Cicero)
"I haven't seen Balbus since you left"
If the action is continuous, where English would use the perfect continuous tense, Latin uses the present tense in the main clause:
(Terence)
"I've been trembling and shivering (lit. "I am trembling and shivering") ever since I caught sight of this woman"
In this kind of sentence, can be followed by a present tense. In one of Martial's poems, the goddess Venus describes her hold over her lover Mars:
(Martial)
"ever since he has been (lit. "is") mine, he has never harmed me with a mistress"
It is even possible to have a present tense in both halves of the sentence, as in the following example from a letter to Atticus, in which Cicero complains about how few letters he's been getting since he left Rome:
(Cicero)
"I tell you, I have been feeling (lit. "I seem to myself") as if I'm completely in exile ever since I've been (lit. "I am") at my villa in Formiae"
"Now that"
Another possible translation in these sentences is "now that":
(Cicero)
"I used to believe that it was easy, but it's a totally different matter now that I am further away from you"
(Cicero)
"the paved portico had the greatest elegance, as has now at last become clear to me, now that the portico itself is completely open and the columns have been polished"
The following example, in a past context, uses the pluperfect tense in the temporal clause:
(Livy)
"now that the enemy had been driven off and there had ceased to be any danger to the walls of Rome, the other consul also left the city"
Future time
is not used of future time in most classical writers, but is occasionally found in technical writers:
(Cato)
"make (the oil) on the third day after (the olive) has been picked (lit. "will have been picked")"
The original meaning of or is "where" (it is related to 'there"), and in questions it always means "where?" (the word for "when?" being ); however, it can also introduce a temporal clause meaning "when" or "as soon as". In poetry, the i is usually short, but occasionally the original pronunciation with a long i is found:
(Horace)
"whenever your face has shone on the people, the day goes more pleasantly"
Past event
As with , when refers to a past event, it is usually followed by the perfect indicative:
(Livy)
"after he had said this, he struck the piglet with a flintstone"
A subjunctive verb after may indicate indirect speech, as in the following example, where the subjunctive indicates that the words "when the signal is given" are part of the order, that is, they indicate when the shout was to be raised, not when the order was given:
(Livy)
"he ordered them all to raise a shout when the signal should be given"
The main verb following a non-iterative clause in past time is almost always perfect or historic present. Very rarely, however, it can be an imperfect. In this case, as after clauses, it describes a situation which is not pre-existing but which arises subsequent to the temporal clause event:
(Livy)
"when news was brought to Coriolanus that a huge crown of women were present, he was even more obstinate (than he had been on the previous two occasions)"
The main verb can also be a historic infinitive, representing a situation:
(Tacitus)
"when Sejanus saw that Drusus's death had been unavenged on his murderers, he began to turn over in his mind how he could cause the downfall of Germanicus's children"
Past situation
As with , the imperfect indicative may occasionally be used after , although this is not very common:
(Sallust)
"when dawn was approaching, suddenly he ordered the soldiers to raise a shout and burst out of the gates"
In the examples below means "after" or "since" ("in view of the fact that") rather than "while":
(Livy)
"after (it became clear that) no one was coming to meet them, they headed for the camp of the enemy"
(Livy)
"when he saw that she was obstinate and not moved even by the fear of death, he added disgrace to fear"
"Whenever"
As with other conjunctions, a perfect indicative tense after may be iterative. Thus in the following example, does not mean "when I came" but "whenever I come":
(Terence)
"whenever I come (lit. "have come"), she finds a reason for me to stay there"
In a past context, a pluperfect or imperfect indicative indicates an iterative situation:
(Sallust)
"whenever there was need for corn, the cohorts used to provide an escort"
(Sallust)
"having been trained in advance by Jugurtha, the cavalrymen, whenever a squadron of Romans began to chase them, did not retreat in close formation or into one place"
From the time of Livy onwards, however, the subjunctive is also used in iterative clauses. In the following example, the tense of is pluperfect subjunctive:
(Livy)
"whenever he had said this, he used to throw a spear into their territory"
This use of the subjunctive in temporal clauses of repeated action is generally not found before Livy. But Cicero uses the perfect subjunctive in the following sentence, probably because he is imagining a supposed case rather than a real one:
(Cicero)
"once someone has perjured himself, he should never be believed again"
When the verb is a generalising 2nd person singular, the subjunctive is regularly used:
(Sallust)
"a good man gets lazier, if you neglect him"
"Where"
The other common meaning of is "where". Often a word such as "place" or 'to that place" in the main clause gives the context for this meaning:
(Nepos)
"he was buried in the same place where he had laid down his life"
(Nepos)
"he reached the place where the king was"
The longer form "wherever" is nearly always used not of time but of place in classical Latin.
(Seneca)
"wherever the Romans have conquered, they inhabit"
"As soon as, when"
The conjunction "as", "as soon as" has various meanings; when it introduces a temporal clause it is followed by an indicative mood. It is often followed by a perfect indicative such as "he saw" or "he came":
(Caesar)
"as soon as Pompey saw that his cavalry had been routed, he left the battle-line"
A common meaning is "as soon as", with another event following immediately:
(Cicero)
"as soon as he had paid his respects to me yesterday, he immediately set out for Rome"
"As, while"
It can also mean "as" or "while", when followed by the imperfect indicative:
(Cicero)
"when Hortensius was being led back home from the election ground, he was met by Gaius Curio"
Main verb imperfect
An clause with the perfect indicative can be followed by an imperfect indicative. Just as when a clause with the perfect indicative is followed by an imperfect, the imperfect describes a pre-existing situation:
(Petronius)
"when I got home, my soldier was lying in bed"
Contrast the same tense used after a or clause, where the imperfect tense describes a subsequent situation (see above).
"As" (manner)
Another frequent, non-temporal, meaning of with the indicative is "as":
(Caesar)
"as we showed earlier"
is not used in sentences in future time.
The word usually means "in whatever way", but there are a few places where it is used in a temporal sense to mean "whenever", as in this hymn to the Muses:
(Horace)
whenever you are with me, I will willingly attempt the raging Bosporus as a sailor"
Past context
The conjunction or , also written as one word, is used in the same way as or . When the sentence refers to a single occasion in the past, the tense in the temporal clause is perfect indicative, as in the following examples:
(Cicero)
"as soon as he was ordered to go into exile, he obeyed"
(Nepos)
"as soon as he caught sight of the enemy, he did not hesitate to join battle"
(Cicero)
"as soon as he touched the province, Verres sent a letter from Messana"
Sometimes alone is used, as in the following example:
(Caesar)
"as soon as our men stood on dry land, they attacked the enemy"
Future context
The future perfect can be used in reference to future time. Here Cicero writes to his friend Atticus:
(Cicero)
"I shall send the book to Varro as soon as I have seen you, if you approve"
(Cicero)
"as soon as I have decided, I will write to you"
Iterative
In the following example, which describes the character of Alcibiades, the pluperfect and imperfect tenses are used in the temporal clause in an iterative sentence in past time:
(Nepos)
"when the occasion demanded, he could be hardworking and put up with hardship...; but as soon as he had relaxed and there was no particular reason to make an effort, he was given over to extravagance, dissolute living, lust, and intemperance"
"While"
When means "while this was happening", explaining the background circumstances of the action in the main clause, it tends to be followed by the present indicative, even in a past context:
(Livy)
"while these things were being done (lit. are being done) in Rome, both consuls were waging war amongst the Ligurians"
(Cicero)
"while this was going on, meanwhile Cleomenes had arrived at the shore of Pelorus"
(Cicero)
"while I was on the way back, Hortensius had come"
In the following example, "she fled" is perfect tense, but "she is fleeing", with a short u, is present tense:
(Ovid)
"(Thisbe) fled into a cave, but while she was fleeing (lit. "is fleeing"), her cloak slipped off her back and she left it behind"
However, other tenses are sometimes possible, such as the perfect in the following example:
(Cicero)
"I learnt this while I was in Capua"
The following has the pluperfect:
(Livy)
"while the contest had turned away the eyes and minds of the enemy in one direction, the wall was captured using ladders"
In the following the imperfect indicative is used:
(Nepos)
"while the sacrifice was being carried out, he asked me whether I would like to set out with him for the camp"
A clause with can also be iterative:
(Cicero)
"whenever I am reading, I tend to agree (with what is written)"
with the present indicative can also be used in a future context. Pliny the Younger pleads with a sick friend to write frequently:
(Pliny)
"for while I'm reading your letters I will feel relieved, but whenever I have finished reading them I will immediately be afraid again"
"while" with the subjunctive
In republican Latin, the verb in a clause, just as with other temporal clauses, was changed into the subjunctive mood when in indirect speech (imperfect subjunctive in a past context, present subjunctive in a present or future context).
(Sallust)
"everyone was eager that he should be noticed while performing such an exploit"
(Nepos)
"he left the princes in charge of that bridge, while he was away" (i.e. until he got back)
However, in Tacitus, there are some exceptions, when the present indicative is retained.
In some authors also, such as Livy and later writers, as well as poets such as Virgil, can take the same construction as circumstantial , even when not in indirect speech, using the imperfect subjunctive:
(Virgil)
"while she was fleeing from you, she failed to see a snake in the grass"
"As long as"
The imperfect indicative after usually means "as long as X was happening", referring to two situations which happened at an identical time:
(Cicero)
"this nation was brave as long as Lycurgus's laws were in force"
In the above example, the perfect indicative tense "it was" implies that the period of Sparta's greatness is now over.
In the following, both clauses have the imperfect indicative tense:
(Cicero)
"nor, during that time I was with you, could you see my soul"
(Caesar)
"as long as the Gauls were at a distance from the fortifications, they were producing a greater effect with the superior number of their weapons"
Other tenses can be used, such as the future indicative in both halves of the following example:
(Cicero)
"Gracchus will continue to be praised for as long as the memory of Roman history remains"
The following has the present indicative in both halves:
(Cicero)
"it is said that as long as there is life, there is hope"
In the following, both tenses are perfect indicative:
"we hoped for those things, as long as fortune was with us"
(Caesar)
"for as long as it was possible to fight on equal terms, a few men withstood a large number of enemy"
"Until"
The conjunction can also mean "until". In the following, it is used with the present indicative:
(Terence)
"think about this until I get back"
More frequently in this meaning it is followed by the subjunctive. In sentences of this kind there is often an idea of "waiting for something to happen":
(Plautus)
"the wolf kept watch until the dogs were dozing"
(Plautus)
"don't expect me to return home by this same road"
(Nepos)
"while the murder was being carried out (i.e. until the business could be completed), he was far away on guard duty"
(Livy)
"Verginius waited until he had a chance to consult his colleague"
(Cicero)
"you write that you are intending to stay in Italy until a letter for you arrives from me"
"Provided that"
Another meaning with the subjunctive is "as long as" in the sense "provided that" ( may also be used in this meaning):
(Accius)
"let them hate, provided that they fear"
The negative in such provisional clauses is :
(Cicero)
"if I seem to have been a bit lazy, I'm not worried, so long as I don't seem that way to you"
Other conjunctions which have similar meanings to are and . is never used by Caesar, and almost never by Cicero, but it is very common in later writers such as Livy, Pliny the Elder, and Tacitus.
"Until"
The original meaning of is "until". In the following example, referring to a future situation, it is followed by a future perfect tense:
(Terence).
"I will not stop until I have finished this"
Referring to the past, the perfect indicative may be used:
(Livy)
"using the knife he forced his way, until he reached the gate"
As with , if there is some idea of waiting for something to happen, the subjunctive is used:
(Livy)
"the Thracians did not move at all, until the Romans had crossed"
(Livy)
"he ordered Spurius Larcius to stand at the Colline Gate until the enemy passed by"
(Gellius)
(he said) they sit there and wait nearly until midday, until their pupils have had a chance to sleep off all their wine of the night before"
(Celsus)
"until it scars over, it should be kept in a bandage"
"While, as long as"
From the Augustan period onwards it can also mean "while" or "as long as":
(Horace)
"as long as I was pleasing to you ... I flourished more blessed than the king of the Persians"
(Livy)
"as long as they were retreating still armed and packed together, it was the infantry's task to pursue them"
In the above examples, the imperfect tense is used in the temporal clause, since it describes to a situation, but the perfect tense is used in the main clause, as is usual in Latin when the length of time a situation lasted is given.
An early form of , but rarely used, was (which is found in Cato, Plautus and once in Nepos). In the following example, referring to the future, is followed by a future perfect:
(Plautus)
"I don't request to be released until he gets back here"
Another rare form is , used four times in Lucretius and four times in Vitruvius but otherwise not found. In this example it is followed by a pluperfect indicative:
(Lucretius)
"with horrifying cries they would call for Death, until cruel agonies had deprived them of life"
"As long as"
The word can have a non-temporal meaning ("to the extent that", "as far as"), but it can also be used in a temporal sense, meaning "as long as". When referring to the past it is regularly followed by the perfect indicative tense:
(Caesar)
"as long as he was able, he put up a very brave resistance"
(Cicero)
"as long as Pompey was in Italy, I didn't give up hope"
"Until"
Another meaning is "until":
(Cicero)
"Milo had been in the senate on that day up until the time when the senate was dismissed"
When referring to the future, just as with clauses, the future or future perfect tense is used where English has a present tense:
(Cicero)
"I shan't stop asking until I hear (lit. "it will have been reported to us") that you have done it"
In the following sentence, the pluperfect subjunctive is used, as if the sentence is reported speech ("I will stay until I have learned"), known as "virtual ":
(Caesar)
"he himself decided to stay in Gaul until he had learnt that the winter-quarters had been fortified"
Another conjunction meaning "while" or "as long as" is or . When referring to the past, it is frequently followed by a perfect indicative:
(Nepos)
"he stayed in one place, for as long as it was winter"
It can also refer to the present, with the present tense:
(Curtius)
"for as long as it flows inside the walls, (the river) retains its name"
In the following example, the tense is future:
(Cicero)
"you will learn for as long as you wish"
In the following, the imperfect indicative is used:
(Pliny)
"this is how a man should grow old, who has devoted himself completely to the republic for as long as was fitting"
The original meaning is "how long?" or "how long...!", and this meaning is also found.
The adverb means "how often" or "as often as"; but it can also be used as a conjunction meaning "whenever", as in the following example:
(Plautus)
"whenever I want to go out, you hold me back"
Cicero often writes in this meaning. In the following example, the verb is in the perfect tense:
(Cicero)
"I made sure I was present every time there was a meeting of the senate"
As with other conjunctions which mean "whenever", Livy tends to use the subjunctive in iterative clauses:
(Livy)
"while I was away, whenever I remembered my country, all these things used to occur to me"
The word is often interrogative ("when?") but sometimes, especially in early Latin, it can be a temporal conjunction. It is usually followed by an indicative verb:
(Plautus)
"he changes his appearance whenever he feels like it"
In other sentences, the meaning shades into "seeing that" or "since":
(Plautus)
"since/when I have lots of relatives, what need do I have of children?"
The iterative form is used by some authors, but it is rare:
(Celsus)
"whenever the fever hasn't appeared, it is safe to take a bath"
can also be an adverb meaning "one day (whenever that may be)", as if is short for :
(Ovid)
"but if the gods see these things, ... one day you will pay me the penalty"
The conjunctions (or ) and () both mean "before". After a negative verb in the main clause, they can be translated with "until". Both are very common, although some authors prefer one (for example, Caesar almost always uses ). Very rarely is found. Another similar conjunction is "on the day before".
Separation of and
If the main clause comes first, the conjunction is often split up, with or being placed before the verb in the main clause. This is especially so if the priority is emphasised as in the following example:
(Caesar)
"(he said that) he had come to Gaul earlier than the Roman people (had done)"
The separation is also common in negative sentences:
(Apuleius)
"they don't go away until they have written something"
Past reference
When referring to the past, a temporal clause with or usually has the subjunctive, especially from the time of the emperor Augustus onwards. However, some sentences use the perfect indicative, especially those which are negative, such as the following:
(Caesar)
"and they did not stop fleeing until they reached the river Rhine"
(Livy)
"and they showed no sign of war until they actually invaded"
(Cicero)
"he did not dare to return the account books to the treasury until Dolabella had been condemned"
Sometimes the verb is indicative even in an affirmative sentence:
(Cicero)
"you came angry with everyone; which I realised and foresaw as soon as I saw you, before you began to speak"
When the sentence mentions a time interval, the use of the indicative more likely:
(Cicero)
"this happened when I was praetor, in the fifth year before I became consul"
(Cicero)
"shortly before he died, he had handed over everything to Heraclius"
(Cicero)
"on the day before I reached Athens he had already departed for Mytilene"
However, there are also types of sentences where the subjunctive is required even in the republican period, for example where one action is done with the hope of preventing another:
(Caesar)
"he quickly put a fortification round the hill before it could be noticed by the enemy"
Similarly, the subjunctive is used if the meaning is "before there was a chance for something to happen":
(Cicero)
"before I could say anything, he got up from his chair and departed"
(Livy)
"many died in the fire before they noticed the arrival of the enemy"
The following has the pluperfect subjunctive:
(Cicero)
"then came Serapion with your letter; even before I had opened it, I told him that you had written to me about him previously"
Another reason for the subjunctive is if there is an idea of insistence ("he refused to leave before conquering..."):
(Nepos)
"and he did not depart from there until he had conquered the entire island"
The subjunctive became more common, and in authors from the time of Livy onwards it is used often without any particular justification. For example, in the following sentences, the relation is purely temporal:
(Livy)
"it was two hundred years before they captured the city of Rome that the Gauls crossed into Italy"
(Suetonius)
"before he left the province, he entered upon a plan of appalling atrocity"
Generalising present
A generalising sentence with or in present time regularly has the present subjunctive, if affirmative:
(Seneca the Elder)
"we see a flash before we hear the sound"
The following generalisation shows the present subjunctive after contrasted with the present indicative after :
(Martial)
"it's hard to say no when you are asked, Sextus,but even harder before you are asked!"
Sometimes, however, the perfect indicative may be used in a generalisation, as in the following:
(Cicero)
"we use our limbs before we learn (lit. "we have learnt") for the sake of what purpose we have them"
When the main verb is negative, the perfect indicative is regular:
(Cicero)
"until earth is (has been) thrown onto a bone, the place where it was cremated is not holy"
Future reference
Referring to the future, a simple present indicative can be used in the temporal clause in sentences such as the following:
(Cicero)
"before I return to the subject, I will say a few words about myself"
(Plautus)
"before I go, is there anything you want to ask me?"
The future simple is not used in these clauses. However, the future perfect is used if the main verb is negative:
(Cicero)
"I shall make no counter-arguments until he has spoken (lit. "before he will have spoken")"
(Cicero)
"I can't decide anything for sure until I see you (lit. "I will have seen you")"
Indirect speech
In indirect or reported speech, the subjunctive is used in the temporal clause. However, in the following sentence the verb is understood from the context, and only an ablative absolute remains:
(Livy)
"they said that would not return from there until the enemies" city had been captured"
Commands and wishes
The subjunctive is usual if the main verb is an imperative:
(Cicero)
"if you love me, do it before you leave"
(Livy)
"before you step outside this circle, give your response"
But the following has the indicative:
(Plautus)
"give me a kiss before you go"
The subjunctive may also be used if the main verb is itself subjunctive, expressing a wish:
(Plautus)
"I'd like to meet this neighbour before I go home"
However, the following wish has the present indicative in the temporal clause:
(Virgil)
"may the Father Almighty drive me to the shadows with a thunderbolt / before I violate you, o Modesty!"
Temporal clause equivalents
As well as temporal clauses, Latin has other ways of expressing the time of the main action in a sentence, and which can substitute for a temporal clause.
Participle phrases
A participle phrase, or a simple participle, is often used as the equivalent of a temporal clause in Latin. Not every type of temporal clause can be replaced by a participle. The type which can be replaced are the circumstantial clauses with , or sometimes a future indefinite clause.
Present participle
The present participle is the equivalent of with the imperfect subjunctive:
(Cicero)
"Plato died while he was writing"
The participle can be in any case, depending on whichever noun it agrees with. In the following sentence, it is in the genitive case:
(Curtius)
"while (Clitus) was saying this, (the king) stabbed him in the side with the spear"
Literally "he pierced with a spear the side of him (as he was) saying these things".
Perfect participle
The perfect participle is the equivalent of with the pluperfect subjunctive:
(Nepos)
"after being sent to help the people of Orchomenus, he was killed by the Thebans"
Ablative absolute
When the phrase is in the ablative case, as in the example below, it is known as an ablative absolute. Such phrases most commonly use the perfect participle, but the present participle can also be used:
"when he learnt of Caesar's arrival (lit. "with Caesar's arrival learnt of"), Ariovistus sent envoys to him"
(Horace)
"you too will become one of the noble springs, when I speak of the ilex-tree placed over your hollow rocks"
(Cicero)
"and I have no doubt that by the time you read this letter, the business will have been completed"
In view of the lack of a present participle of the verb "I am" in Latin, sometimes an ablative phrase alone, without a verb, can stand for a temporal clause:
(Nepos)
"when I was a small boy"
After a preposition
A participle phrase can sometimes follow a preposition of time:
(Plautus)
"make sure you come before the sun has set"
(Livy)
"these are the things that were done at home and on campaign in the first year after the kings were expelled"
Verbal nouns
Some verbal nouns, such as "arrival" and "return", can be used in phrases of time:
(Caesar)
"on his arrival, the Bituriges sent envoys to the Aedui to ask for help"
(Caesar)
"Afranius had gathered nearly all the corn in Ilerda before Caesar's arrival"
Relative clause
The ablative relative pronoun "on which" can be used to mean 'the day on which" or 'the time at which", and thus introduce a quasi-temporal clause, as in the following examples from the historian Curtius. The pluperfect subjunctive is used, as the clauses are included in a sentence of indirect speech:
(Curtius)
"but he began shouting that the very moment he'd heard he had run to report the matter to Philotas"
(Curtius)
"and again he kept on asking how many days it had been (lit. 'the how-many-eth day it was") since Nicomachus had brought the accusation to him"
The feminine is similarly used to refer to a night:
(Petronius)
"on that night, on which they got married"
(Tacitus)
"on the night when the legion was setting off"
Coordination
The kind of temporal clause is sometimes expressed in poetry simply by two sentences joined by , or "and", as in the following example from Virgil:
(Virgil)
"he had spoken, and now the fire was heard along the walls more loudly"
Multiple temporal clauses
Temporal clauses and participial phrases standing for temporal clauses are especially common in historical writing. Nutting cites the following typical example from Julius Caesar, where a temporal clause with cum is placed between two participle phrases:
(Caesar)
"the Germans, having heard the shouting behind them, when they saw their comrades being killed, having cast down their weapons ... threw themselves out of the camp."
In Nepos comes this sentence with a temporal clause, an ablative absolute, and a main verb:
(Nepos)
"whom when the barbarians saw that he had escaped the fire, by throwing missiles at him from long range, they killed"
Livy also writes sentences containing a mixture of participial and temporal clauses. The following sentence has four participles or participial phrases, a cum clause, and a postquam clause, followed by the main verb:
(Livy)
"where, having been welcomed politely by those who were ignorant of his plan, when after dinner he had been led into the guest bedroom, burning with love, after everything seemed safe round about and everyone seemed to be asleep, having drawn his sword, he came to the sleeping Lucretia"
In the following sentence by Cicero, two different temporal clauses, with and , follow each other:
(Cicero)
"as soon as I reached my villa at Arpinum, after my brother had joined me, at first our conversation (and it was a long one) was about you"
Allen and Greenough cite this sentence from Livy, which consists of two temporal clauses, and no fewer than six perfect participles:
(Livy)
"the Volsci, the small hope they had in arms every other hope having been cut off, after they had made trial of (it), apart from other difficulties having also joined battle at a place unsuitable for fighting and even more unsuitable for fleeing, when they were being slaughtered on all sides, after turning from fighting to prayers, with their commander surrendered and their weapons handed over, having been sent under the yoke, with a single garment each, full of ignominy and disaster, they were allowed to depart."
These long sentences, in which a number of subordinate clauses and participle phrases are followed by a main verb, are known as "periods".
Bibliography
Bennett, Charles Edwin (1895). Latin Grammar, Boston; pp. 187–191.
Gildersleeve, B. L. & Gonzalez Lodge (1895). Gildersleeve's Latin Grammar. 3rd Edition. (Macmillan); pp. 359–376.
Greene, John (1907). "Emphasis in Latin Prose". The School Review, Nov., 1907, Vol. 15, No. 9, pp. 643–654.
Greenough, J. B. et al. (1903). Allen and Greenough's New Latin Grammar for Schools and Colleges. Boston and London; pp. 350–359.
Hullihen, Walter (1911a). "A Chapter from an Unpublished Latin Syntax, with Prefatory Discussion". The Classical Weekly, Vol. 4, No. 25 (Apr. 29, 1911), pp. 194–196. (A discussion of clauses.)
Hullihen, Walter (1911b). "A Chapter from an Unpublished Latin Syntax, with Prefatory Discussion (Concluded)". The Classical Weekly, Vol. 4, No. 26 (May 6, 1911), pp. 203–205.
Kennedy, Benjamin Hall (1871). The Revised Latin Primer. Edited and further revised by Sir James Mountford, Longman 1930; reprinted 1962; pp. 184–186.
Lewis, C. T. & Short, C. (1879). A Latin Dictionary.
Nutting, H. C. (1916). "Where the Latin Grammar Fails". The Classical Weekly, Vol. 9, No. 20 (Mar. 18, 1916), pp. 153–157.
Nutting, Herbert C. (1920). "Notes on the Cum-Construction". The Classical Journal, Vol. 16, No. 1 (Oct., 1920), pp. 26–33.
Nutting, H. C. (1933). "On the History of the Cum-Construction". The American Journal of Philology, Vol. 54, No. 1 (1933), pp. 29–38.
Petersen, Walter (1931). 'The Evidence of Early Latin on the Subjunctive in Cum-Clauses". Classical Philology, Oct., 1931, Vol. 26, No. 4, pp. 386–404.
Schlicher, J. J. (1909). 'the Temporal Cum-Clause and Its Rivals". Classical Philology Vol. 4, No. 3 (Jul., 1909), pp. 256–275.
Smith, W. & Hall, T. D. (1871). English-Latin Dictionary.
Steele, R. B. (1910). "Relative Temporal Statements in Latin". The American Journal of Philology, 1910, Vol. 31, No. 3, pp. 265–286.
Viti, Carlotta (2013). 'The idiosyncrasy of the cum inversum and of Latin subordination'. In: Bodelot, Colette; Gruet-Skrabalova, Hana; Trouilleux, François. Morphologie, syntaxe et sémantique des subordonnants. Clermont-Ferrand: Presses universitaires Blaise Pascal, pp. 115–130.
Woodcock, E.C. (1959), A New Latin Syntax, (Bristol Classical Press), pp. 172–195.
References
Latin grammar
Clauses
Time in linguistics | Temporal clause (Latin) | [
"Physics"
] | 14,312 | [
"Spacetime",
"Time in linguistics",
"Physical quantities",
"Time"
] |
64,752,725 | https://en.wikipedia.org/wiki/2020%20Beirut%20explosion | On 4 August 2020, a large amount of ammonium nitrate stored at the port in Beirut, Lebanon exploded, causing at least 218 deaths, 7,000 injuries, and US$15 billion in property damage, as well as leaving an estimated 300,000 people homeless. A cargo of 2,750 tonnes of the substance (equivalent to around 1.1 kilotons of TNT) had been stored in a warehouse without proper safety measures for the previous six years after having been confiscated by Lebanese authorities from the abandoned ship . A fire in the same warehouse preceded the explosion.
The blast was so powerful that it was felt throughout Lebanon. It was also felt in Turkey, Syria, Palestine, Jordan, Israel, and parts of Europe, and was heard in Cyprus, more than away. It was detected by the United States Geological Survey as a seismic event of magnitude 3.3 and is considered one of the most powerful non-nuclear explosions on record. It was powerful enough to affect Earth's ionosphere. The blast was also the largest single-fired ammonium nitrate explosion in history.
Following the explosion, there were suspicions regarding Hezbollah's involvement due to allegations that the explosion occurred at a site storing Hezbollah's weapons. Hezbollah denied these allegations but has been actively involved in demonstrations against the investigation into the explosion.
The Lebanese government declared a two-week state of emergency in response to the disaster. In its aftermath, protests erupted across Lebanon against the government for their failure to prevent the catastrophe, joining a larger series of protests which had been taking place across the country since 2019. On 10 August 2020, Prime Minister Hassan Diab and the Lebanese cabinet resigned.
The adjacent grain silos were badly damaged. In July and August 2022, part of the silos collapsed following a weeks-long fire in the remaining grain.
Background
The economy of Lebanon was in a state of crisis before the explosion, with the government having defaulted on debt, the Lebanese pound plunging, and a poverty rate that had risen past 50%. In addition, the COVID-19 pandemic had overwhelmed many of the country's hospitals, several of which were already short of medical supplies and unable to pay staff due to the financial crisis. The morning before the explosion, the head of the Rafik Hariri University Hospital, which served as the main COVID-19 medical facility in Lebanon, warned that it was approaching full capacity.
The government-owned Port of Beirut serves as the main maritime entry point into Lebanon and a vital piece of infrastructure for the importation of scarce goods. The Beirut Naval Base is a part of the port. The port included four basins, sixteen quays, twelve warehouses, a large container terminal, and a grain elevator with a total capacity of 120,000 tonnes that served as a strategic reserve of cereals for the country. The grain elevator was built in the 1960s as part of an expansion plan advanced by Palestinian banker Yousef Beidas.
MV Rhosus
On 27 September 2013, the Moldovan-flagged cargo ship set sail from Batumi, Georgia, to Beira, Mozambique, carrying of ammonium nitrate. Rhosus was owned by a company based in Panama but was regarded by the captain as under the de facto ownership of Russian businessman Igor Grechushkin. The shipment had been ordered by an African explosives manufacturing company for mining in Mozambique. However, reporting by Der Spiegel has found that it was not Grechushkin who owned Rhosus, but rather Cypriot businessman Charalambos Manoli, who maintained a relationship with the bank used by Hezbollah in Lebanon.
On 21 November 2013, the ship made port in Beirut. Some sources said it was forced to port due to mechanical issues and possibly engine problems, while other sources claimed the owner did not have sufficient funds to pay tolls for the Suez Canal and attempted to take on a shipment of heavy machinery in Beirut. The heavy machinery was stacked on top of the doors to the cargo space containing the ammonium nitrate, causing the doors to buckle, which damaged the ship. After inspection by port state control, Rhosus was deemed unseaworthy, and was forbidden to set sail. Eight Ukrainians and one or two Russians were aboard, and with the help of the Ukrainian consul, five Ukrainians were repatriated, leaving four crew members to care for the ship.
Grechushkin reportedly went bankrupt, and after the charterers lost interest in the cargo he abandoned Rhosus. The ship soon ran out of provisions, and the remaining crew were unable to disembark due to immigration restrictions. According to Lloyd's List, port state control seized Rhosus on 4February 2014 due to US$100,000 in unpaid bills. The ship had accrued port fees and been fined for refusing cargo. Lawyers argued for the crew's repatriation on compassionate grounds because of the danger posed by the cargo still aboard the ship, and an Urgent Matters judge in Beirut allowed them to return home. They had been forced to live aboard the ship for about a year.
By order of the judge, Rhosuss cargo was brought ashore in 2014 and placed in Warehouse 12 at the port, where it remained for the next six years. Rhosus sank in the harbor in February 2018.
Lebanese customs officials had sent letters to judges requesting a resolution to the issue of the confiscated cargo, proposing that the ammonium nitrate be either exported, given to the Lebanese Armed Forces or sold to the private Lebanese Explosives Company. Letters had been sent on 27 June and 5 December 2014, 6 May 2015, 20 May and 13 October 2016, and 27 October 2017. One of the letters sent in 2016 noted that judges had not replied to previous requests, and pleaded:
Each time, the requests were procedurally declined due to errors by the customs officials. However, the officials persisted in making the same requests instead of correcting the errors. Legal experts also said that the customs officials could have confiscated the material unilaterally.
Explosion
Fire and first explosion
Around 17:45 local time (14:45 UTC) on 4 August 2020, a fire broke out in Warehouse 12 at the Port of Beirut. Warehouse 12, which was waterside and adjacent to the grain elevator, stored the ammonium nitrate that had been confiscated from Rhosus alongside a stash of fireworks. Around 17:55 local time (14:55 UTC), a team of nine firefighters and one paramedic, known as Platoon 5, was dispatched to fight the fire. On arrival the fire crew reported over the radio that there was "something wrong" as the fire was immense and produced "a crazy sound."
The initial explosion, at about 18:07 local time (15:07 UTC), likely triggered by the stored fireworks, created a large plume of grey smoke and bright firework flashes, and heavily damaged Warehouse 12 with a force equivalent to around 1.5–2.5 tons of TNT.
Final explosion
The second explosion, 33 to 35 seconds later, was far more substantial and felt in northern Israel and in Cyprus, away. It rocked central Beirut and created a large red-orange cloud, briefly ringed by a white condensation cloud. The red-orange color of the smoke from the second explosion was caused by nitrogen dioxide, a byproduct of ammonium nitrate decomposition.
By the next morning, the main fire that led to the explosion had been extinguished.
Yield
Despite inefficient transmission of the shock waves into the ground, the United States Geological Survey measured the event as a 3.3 local magnitude earthquake, while the Jordan Seismological Observatory reported that it was equivalent to a 4.5 earthquake. A study of seismic signatures of the explosion by the Federal Institute for Geosciences and Natural Resources in Germany produced a yield estimate between 0.5 and 1.1 kt of TNT. Experts from the Blast and Impact Research Group at the University of Sheffield estimated that the explosion was one of the largest artificial non-nuclear explosions ever recorded. Later, they were able to quantitatively support this rapid estimate as they compiled more distance versus time of arrival data as new videos of the explosion became available on social media platforms. Their study found that the best estimate and upper bound prediction of the yield of the explosion are 0.5 and 1.12 kt of TNT, respectively. This is equal to around 1 GWh of energy. Another study used several videos of the explosion to describe the evolution of the fireball size and estimated the Beirut explosion yield to be 0.6 ± 0.3 kt of TNT. The Beirut explosion was similar to explosions of large amounts of ammonium nitrate in Texas City, United States, in 1947; in Toulouse, France, in 2001; and Tianjin, China, in 2015.
An independent estimate by the International Monitoring System of the Comprehensive Nuclear-Test-Ban Treaty Organization based on infrasonic data obtained an explosive yield equivalent to 0.5–1.1 kt of TNT, making it the sixth-largest accidental artificial non-nuclear explosion in human history.
Aouad et al. (2021) derived the kinematics of the fireball from publicly available videos. Considering a time of separation between the fireball and the shock wave at about 170 milliseconds, they concluded a TNT equivalent mass of 0.2 ± 0.08 kt of TNT or 520 ± 200 tons of ammonium nitrate at a distance of 130 meters from the explosion center. This result is consistent with Dewey 2021 that suggests that the Beirut explosion TNT equivalence is an increasing function of distance.
Temsah et al. 2021 estimated the magnitude of the explosion. The research was based on a structural engineering approach with numerical non-linear finite element modeling of the grain elevator facing Warehouse 12 where the explosion took place. The numerical study model was based on silos data (geometrical and material properties) and the use of the Conventional Weapons Effects Blast Loading (CONWEP), and the Coupled Eulerian-Lagrangian (CEL) methods to generate the blast load. The analysis results proved that an amount equivalent to 564 t of AN (or 220 t of TNT) was adequate to generate damages similar to those resulting from the explosion. This amount represents 20.5% of the original stored amount (2750 t). As for the state of the grain elevator, results showed it was structurally unstable and should be demolished or properly strengthened.
Kim and Pasyanos (2021) put the yield between 0.62–1.25 kt, with the best and most likely estimate at 0.9 kt of TNT, with a likely depth of 2 m.
It has been suggested that not all of the ammonium nitrate was still in the warehouse at the time of the explosion. Some experts estimated that there were only 700 to 1,000 tonnes remaining out of the original 2,750, with the rest having been removed or stolen since 2014. The US Federal Bureau of Investigation estimated there were about 500 tonnes left, a number which was later cited by Prime Minister Hassan Diab. However, there were also two experts who concluded that most or all of the ammonium nitrate exploded.
Cause
Warehouses at the Port of Beirut were used to store explosives and chemicals including nitrates, which are common components of fertilizers and explosives. The General Director of General Security, Major General Abbas Ibrahim, said the ammonium nitrate confiscated from Rhosus had exploded. The of ammonium nitrate was the equivalent to around . The failure to remove the materials from the warehouse and relocate them was attributed to mismanagement of the port, corruption of the government, and inaction of the flag registry's country and ship owner.
The Lebanese Broadcasting Corporation International (LBCI) reported that, according to attendees of a Higher Defence Council briefing, the fire was ignited by workers welding a door at a warehouse. A former port worker said that "[t]here were 30 to 40 nylon bags of fireworks inside warehouse 12" that he had personally seen. An American diplomatic cable on 7 August said it "remains unclear ... whether fireworks, ammunition or something else stored next to the ammonium nitrate might have been involved" in worsening the warehouse fire and igniting the ammonium nitrate. A port worker said Warehouse 12 was "not in regular use", and that "those in charge only used to open the warehouse to stack inside it materials confiscated upon judicial orders or perilous products", though he had not seen this to include any armaments.
Casualties
A total of 218 people were confirmed dead from the explosion, with over 7,000 injured. Foreigners from at least 22 countries were among the casualties. Several United Nations naval peacekeepers who were members of the UN Interim Force in Lebanon (UNIFIL) were injured by the blast. The United Nations High Commissioner for Refugees (UNHCR) reported that 34 refugees were among the dead and missing, and an additional 124 refugees were injured. At least 150 people were left permanently disabled as a result of the explosion.
Notable casualties
All ten members of Platoon 5, a team of nine firefighters and a paramedic, died at the scene of the blast. Nazar Najarian, the secretary-general of the Kataeb Party, died after sustaining severe head injuries. French architect Jean-Marc Bonfils died after sustaining serious injuries at his apartment in the East Village building in Mar Mikhaël. He had been live-streaming the fire at the warehouse on Facebook at the time. Lady Cochrane Sursock, philanthropist and member of the Sursock family, died on 31 August from injuries sustained from the blast.
Damage
The explosion overturned cars and stripped steel-framed buildings of their cladding. Within the port area, the explosion destroyed a section of shoreline and left a blast crater roughly in diameter and in depth. Homes as far as away were damaged by the blast, and up to 300,000 people were left homeless by the explosion. The grain elevator was largely destroyed, exacerbating food shortages caused by the COVID-19 pandemic and the financial crisis. About of grain were lost, leaving the country with less than a month's worth of grain in reserve. However, part of the elevator's sturdy structure survived, shielding a large area of western Beirut from greater destruction.
The damage from the blast affected over half of Beirut, with the likely cost above US$15 billion and insured losses at around US$3 billion. Approximately ninety percent of the city's hotels were damaged and three hospitals completely destroyed, while two more suffered damage. Dozens of injured people brought to nearby hospitals could not be admitted because of the damage to the hospitals. Windows and other installations of glass across the city were shattered.
Saint George Hospital, one of the city's largest medical facilities, was less than from the explosion, and was so badly damaged that staff were forced to treat patients in the street. Four nurses died from the initial blast, fifteen patients died after their ventilators stopped working, and several child cancer patients were injured by flying glass. Within hours, after discharging all its patients and sending some to other facilities, Saint George Hospital was forced to close. The hospital's director of intensive care, Dr. Joseph Haddad, was quoted as saying: "There is no Saint George Hospital anymore. It's fallen, it's on the floor... It's all destroyed. All of it."
The Sursock Museum was severely damaged, as was much of its artwork, and some ceramics were completely destroyed. The atelier for the fashion house Sandra Mansour was heavily damaged by the explosion. Sursock Palace, a 160-year-old Beirut landmark that was listed as a cultural heritage site, also sustained heavy damage, as did its many works of art. Some glass artifacts in the Archaeological Museum of the American University of Beirut were also destroyed, and the huge 118-year-old door which opened onto the main exhibition space was blown off its hinges. Bustros Palace, which hosts the Ministry of Foreign Affairs and Emigrants, was severely damaged. The Armenian Catholicosate in Antelias sustained great damage. All the stained glass windows of the National Evangelical Church were blown out. The FIBA Asia headquarters was also heavily damaged. Embassies in and around Beirut reported varying degrees of damage to their buildings; the embassies of Argentina, Australia, Finland, Cyprus, and the Netherlands, which were close to the blast, sustained heavy damage, while minor damage was reported from the South Korean, Hungarian, Kazakh, Russian, Bulgarian, Romanian, and Turkish embassies.
Shipping
The cruise ship Orient Queen, berthed near Warehouse 12, suffered extensive damage and capsized overnight. Two members of the crew were killed, and seven crew members were injured. On 7 August, the first lawsuit related to the explosions was filed by the ship's owners, Abou Merhi Cruises, whose offices were also destroyed. The Bangladesh Navy corvette BNS Bijoy, which participated in UNIFIL, was also damaged.
The edible-oil tanker ship AmadeoII, being used as a bunker barge at the port, was nearest to the explosion, which deposited the mangled remains of the ship on a nearby quay. The ship's crew died in the explosion. Two large livestock carriers, Abou KarimI and Abou KarimIII, laid up at the end of Berth 09, very close to Warehouse 12, were heavily damaged. Abou KarimI became unstable, keeled over onto the adjacent Abou KarimIII and shortly afterwards capsized. The livestock carrier Jouri and the cargo ships Mero Star and Raouf H were also close to the blast and suffered serious damage; AIS from these ships stopped broadcasting at the time of the explosion.
Hapag-Lloyd's offices in Beirut were destroyed. CMA CGM's offices, located a few hundred meters away from the site of the explosion, were severely damaged. One employee died and two were severely injured.
Airport
Beirut–Rafic Hariri International Airport, the city's main airport, about from the site of the blast, sustained moderate damage to the terminal buildings during the explosion. Doors and windows were destroyed, and ceiling tiles were shaken loose by the shockwave, severing electrical wires. Despite the damage, flights continued.
Subsequent collapses
In July 2022, grains remaining in the silo caught fire due to a combination of fermentation and summer heat. On 31 July, the northern part of the silo collapsed. Two further collapses occurred in August. The government had ordered the demolition of the silos in April 2022, but families of blast victims objected, saying it should be preserved as a memorial site.
Investigation
The government formed an investigative committee led by Prime Minister Hassan Diab, which announced it would submit its findings to the Council of Ministers of Lebanon by 11 August 2020. The committee includes the justice, interior and defence ministers, and the head of the top four security agencies: the Armed Forces, General Security, Internal Security Forces, and State Security. The investigation was to examine whether the explosion was an accident or due to negligence, and if it was caused by a bomb or another external interference. President Michel Aoun rejected calls for an international probe despite demands from world leaders.
On 5 August, the Council agreed to place sixteen Beirut port officials who had overseen storage and security since 2014 under house arrest, overseen by the army, pending the investigation into the explosions. In addition, the general manager of the port, Hassan Koraytem, and the former director general of Lebanon's customs authority, Shafiq Merhi, were arrested. Later, on 17 August, the incumbent director-general of Lebanon's customs authority, Badri Daher, was also arrested. Also, former ministers of both finance and public works were due to be interrogated by a judge appointed by the council. In the meantime, state prosecutor Ghassan Oueidat ordered a travel ban on seven individuals, including Koraytem. While Acting Justice Minister Marie-Claude Najm unsuccessfully demanded an international investigation into the blast, she also noted that "...this case is a chance for the Lebanese judiciary to prove they can do their jobs and win back the confidence of the people". On 19 August, a Lebanon judge ordered the arrests of more suspects over the explosion, making the total number of accused 25.
The Lebanese judge Fadi Sawan, who has been responsible for the investigation, summoned former Minister of Transportation and Public Works Ghazi Aridi, Labor Ministers Ghazi Zaiter, Youssef Fenianos, and Michel Najjar, General Director of the Lebanese State Security Tony Saliba, Director General of Lebanon's Land and Maritime Transport division, Abdul-Hafeez Al-Qaisi, and General Director of General Security, Major General Abbas Ibrahim.
In September, Lebanon's state prosecution asked Interpol to detain two Russian citizens, the captain and the owner of Rhosus, as its cargo of ammonium nitrate was blamed for the explosion. In January 2021, Interpol issued Red Notices against the two Russians as well as a Portuguese man.
In December 2020, Lebanon's outgoing Prime Minister Diab and three former ministers were charged with negligence over the Beirut port explosion. The former ministers were former finance minister Ali Hassan Khalil, Ghazi Zeiter, and Youssef Fenianos, both former ministers of public works. Zeitar was transport and public works minister in 2014, followed by Fenianos in 2016, who held the job until the beginning of 2020. Khalil was finance minister in 2014, 2016, and until 2020.
On 28 January 2021, Syrian-Russian businessman George Haswani denied any links to the Beirut explosion. He told Reuters he did not know anything about a company linked to the process of buying a shipment of chemicals that exploded. In an interview with Reuters at his home in Damascus, Haswani said that he had resorted to the Cypriot company Interstatus to register his company, which is the same agent that registered the Savaro company, and that the agent company had moved the registration site of the two companies to the same address on the same day. However, Haswani said that he did not know anything about Savaro and that any links between it and his company are just a coincidence because the two companies have the same agent. As stated in previous reports, Reuters was unable to determine whether Haswani had anything to do with Savaro. Haswani said, "I don't know what other companies are registered by this Cypriot company, five or three or 70 or more... It is a fabricated media whirlwind. We don't know Savaro and we hadn't heard about them before this." Interstatus did not respond to a request for comment. Marina Psyllou, the director of the "Interstatus" company, was listed in the registration documents of the company (Savaro) as the only owner and director of the company, but she denied that she was the real manager of the company. She told Reuters in mid-January 2021 that the beneficial owner of the company was another person, whom she refused to identify. She added that Savaro was a dormant company that had never conducted business. Haswani said that he was not contacted by any investigators from Lebanon or any other country regarding the explosion and that he will soon work to file a legal case in Paris against media reports linking him to the explosion. He continued, "I am living my life normally and laughing because I am someone who knows well that I have nothing to do with this matter at all. Why would I worry?"
On 15 April 2021, six detained people were released, including two officers, although they were not allowed to travel out of Lebanon.
In September 2021, OCCRP published an investigation, that linked Savaro Limited to a Ukrainian company trading chemicals, directed by Ukrainian citizen Volodymyr Verbonol. The report also mentions that only 20% of the nitrate originally stored in the warehouse was actually left when it exploded, raising questions about what happened with the rest.
On 14 October 2021, six people were killed and at least 30 injured in a gunfire exchange in Beirut during protests by members of the Shia Amal and Hezbollah outside the Justice Palace, which demanded an end to the investigations led by Judge Tarek Bitar, for they deemed him as too much centered on their political allies.
On 21 November 2021, the BBC reported that legal groups representing victims of the blast had sent letters on three occasions to UN Secretary General Antonio Guterres requesting more information from UNIFIL, but had received no acknowledgment from the UN. A day later, the Lebanese Foreign Minister Abdallah Bouhabib announced that Lebanon received satellite images from Russia of the port from the day of the blast in 2020. These were the first official images made available from any foreign government.
Throughout 2022, the investigation stalled. As of 8 June, parliamentary immunity, as well as outstanding complaints and other procedural roadblocks initiated by two members of Parliament and former ministers (namely, Ali Hassan Khalil and Ghazi Zaiter), continued to prevent significant progress in the case.
On 16 January 2025, the investigation was resumed following the nomination of Nawaf Salam as prime minister and the Israel–Hezbollah conflict. Ten people were sentenced, including security, customs and military personnel.
Relief operations
The Lebanese Red Cross said every available ambulance from North Lebanon, Bekaa, and South Lebanon was being dispatched to Beirut to help patients. According to the agency, a total of 75 ambulances and 375 medics were activated in response to the explosions. Lebanese President Michel Aoun said the government would make up to 100billion pounds (US$66million) in aid available to support recovery operations. The ride-sharing app Careem offered free rides to and from hospitals and blood donation centers to anyone willing to donate blood. Volunteers removed debris while local business owners offered to repair damaged buildings for free in the absence of a state-sponsored cleanup operation. A temporary hospital was established in the city by the Iranian Red Crescent Society.
Health Minister Hamad Hasan requested that international aid be sent to Lebanon; a number of countries sent in food, medical supplies, field hospitals, medical workers, and rescue teams. On 9 August, a multinational summit hosted by France raised 253 million euros in aid. The money pledged was not to be given to the Lebanese government, but rather to the people of Lebanon through the United Nations, other international organizations, and non-governmental organizations. On 14 August, a $565 million appeal for Lebanon was launched by the United Nations, including initial recovery efforts, as well as immediate humanitarian aid.
In the first week after the explosion, civilians gathered in hundreds to volunteer to clean up the debris on the streets and inside homes and businesses in Gemmayze, Achrafieh, and Karantina neighbourhoods. Many civil society organizations offered equipment and food to the volunteers, while many residents and businesses opened their homes and hotels for free to those who lost their homes in the blast.
UNESCO played a leading role in the rescue and reconstruction of historic buildings, with Blue Shield International assessing the damage to houses, museums and libraries, and the International Council of Museums providing expertise. Blue Shield International, the United Nations Interim Force in Lebanon and the Lebanese Armed Forces put together a project to secure and protect cultural assets. According to Karl von Habsburg, founding president of Blue Shield International, the protection of cultural property in Beirut was not only about securing buildings, but also about preventing looting and water damage, taking dangerous chemical substances into account. The efforts also included the restoration of schools.
On 6 August 2020, the Lebanese Forces Party's executive chairman Samir Geagea was the first politician to visit Beirut and launched from there a relief committee, Ground-0, under the leadership of the former minister Dr. May Chidiac to support in rebuilding Beirut. In December 2020, the committee achieved repairing 709 houses, assisted 5300 individuals and 2300 families, distributed 14000 food rations, made 2540 medical consultations, and provided 2030 individuals with medicine. In addition, the committee distributed more than 150 scholarships for Beirut schools' students.
Reactions
Domestic
Prime Minister Hassan Diab announced that 5 August, the day after the explosion, would be a national day of mourning. The Lebanese government declared a two-week state of emergency. President Aoun said the government would provide support to displaced people, and the Ministry of Health would meet the expense of treatment for the wounded. Marwan Abboud, the governor of Beirut, said he arrived at the scene to search for firefighters who were on the site attempting to control the fire that was raging before the second explosion. He broke down in tears on television, calling the event "a national catastrophe". "It resembles to what happened in Japan, in Hiroshima and Nagasaki. That's what [it] reminds me of. In my life, I haven't seen destruction on this scale," he said. Lebanese civilians from every region in Lebanon came to help by offering food, cleaning the streets, and helping NGOs.
Multiple members of the Lebanese parliament resigned in protest, including Marwan Hamadeh, Paula Yacoubian, all three Kataeb Party MPs, Neemat Frem, Michel Moawad, Dima Jamali, and Henri Helou. The Lebanese ambassador to Jordan, Tracy Chamoun, also resigned on live television. On the night of 6 August, the protests against the government that had been ongoing since the previous October resumed, with dozens of protestors near the parliament building calling for the resignation of Lebanese government officials. On 8August, Diab called for early elections, saying it would be the only way for the country to exit the crisis.
On 9 August, the information minister of Lebanon, Manal Abdel Samad, and then the environment minister, Damianos Kattar, resigned, the first government resignations since the explosion. On 10 August, the justice minister, Marie-Claude Najm, also resigned, followed by the resignation of the entire Lebanese cabinet. Shortly after the resignation of the cabinet, Lebanese Prime Minister Hassan Diab stepped down from office. President Michel Aoun accepted the resignation of the government and the Prime Minister, and asked the government to stay on in a caretaker capacity until a new cabinet is formed.
The Ground-0 Relief Committee, an initiative by the Lebanese Forces Party, launched a petition for an international investigation. The petition was signed by the relatives of the victims and the missing, by the injured as well as by those whose homes, businesses, or establishments have been damaged. The document was sent to the UN Secretary General, Antonio Guterres, through his special coordinator for Lebanon, Ján Kubiš, in order to take the necessary steps to appoint an international commission of inquiry.
The Lebanese Forces Party MPs called for an international investigation into the causes of the double explosion at the port of Beirut on 4 August 2020. They asked the Secretary-General of the United Nations, António Guterres, on 22 February 2021 for the creation of an international commission to be established under the United Nations, which would be responsible for carrying out the investigations. The Members of Parliament, Georges Okais, Imad Wakim, Eddy Abillammaa, and Fady Saad, presented a petition to this effect to the United Nations Special Coordinator in Lebanon, Najat Rochdi.
International
Representatives of multiple countries, as well as the United Nations (UN), offered condolences. In addition to those countries which provided aid, others offered to do so. Notably, Israel offered aid via UN channels, as Israel and Lebanon have no diplomatic ties and are technically at war; the offer was refused by the Lebanese government. Former Israeli Member of Knesset Moshe Feiglin hailed the tragedy as a gift from God, celebrating the incident and describing it as a "spectacular firework show." Despite years of conflict, including the 2006 Lebanon War, both Israel and senior Hezbollah officials ruled out Israeli involvement in the explosion, despite claims and allegations spread via social media.
The International Charter on Space and Major Disasters was activated on 5August, thus providing for widespread usage of various corporate, national, and international satellite assets on a humanitarian basis. Several countries expressed solidarity by lighting up landmarks and monuments in the colors of the Lebanese flag, including the Tel Aviv City Hall, whereas the Eiffel Tower in Paris went dark at midnight, and the Arab League flew its flag at its headquarters in Cairo at half-mast. Some figures from the right-wing criticized the display of the flag of Lebanon, an "enemy state", in Tel Aviv. There was also backlash inside Lebanon against the Israeli gesture.
Following the explosion, the Netherlands, Turkey, and the United Kingdom sent search and rescue teams. Egypt sent several planes with tons of medical aid and food to Lebanon. The Egyptian embassy also established a field hospital. On 5 August 2020, Qatar started providing urgent medical aid. The Qatari Emiri Air Force delivered field hospitals, respirators, and generators to Beirut. In addition, Qatar's Emir Sheikh Tamim bin Hamad Al Thani donated to Lebanon. On 6 August 2020, Kuwait provided 36 tonnes of urgent humanitarian and medical aid to Lebanon including wheelchairs, blood bags, and 10 ambulances.
As a result of the explosion, concerns were raised about the storage of ammonium nitrate in other ports across the world. Large quantities of the chemical compound were removed from storage in Egypt, India, Romania, and Senegal.
On April 30, 2021, German firm Combi Lift which had loaded its ship with 59 containers of hazardous substances left Beirut port for disposal in Europe.
In August 2021, a memorial event marking the one-year-anniversary of the explosion was held in tribute to the victims at the Port of Beirut, joined by UN officials and International Labour Organization Regional Director Ruba Jaradat.
In December 2021, the United Nations Economic Commission for Europe, United Nations Office for Disaster Risk Reduction, United Nations Office for the Coordination of Humanitarian Affairs, United Nations Environment Programme, Organisation for Economic Co-operation and Development, International Labour Organization, and International Maritime Organization held a seminar in follow-up to the explosion. National governments of Lebanon, Estonia, France, South Africa, and others shared lessons learned from the explosion. The seminar called for action to better manage the risks of chemicals in ports.
Conspiracy theories
Numerous conspiracy theories emerged on social media in the days following the explosion. The main themes were that there was a significant weapons cache belonging to Hezbollah stored at the Port of Beirut, and that Israel wished to destroy those weapons. The theories said that Israel launched an attack and the level of destruction took them by surprise. Israel, Lebanon, and Hezbollah all denied this theory, and blame the ammonium nitrate stored in the port.
See also
List of 21st-century explosions
Largest artificial non-nuclear explosions
List of industrial disasters
Halifax Explosion
Texas City disaster
2015 Tianjin explosions
2022 Sitakunda fire
Notes
References
Further reading
External links
Beirut Explosion – in Pictures by The Guardian
In Pictures: Huge Explosion Rocks Beirut by CNN
Photos: Explosion Leaves Beirut in Shatters by NPR
The Lebanon Explosions in Photos by The New York Times
Explosion in Beirut: Photos From a City Still Reeling From the Blast by Time
Before and after satellite photos from CNN
Map of the Port of Beirut with several warehouses numbered, including Warehouse 12 next to the silos
Forensic Architecture overview
Slow-motion footage of the blast
2020 fires in Asia
2020 in Lebanon
2020 explosions
Ammonium nitrate disasters
Articles containing video clips
August 2020 events in Lebanon
Explosions in 2020
2020
Fires in Lebanon
Industrial fires and explosions
Maritime incidents in 2020
2020 disasters in Lebanon
Scandals in Lebanon | 2020 Beirut explosion | [
"Chemistry"
] | 7,272 | [
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64,753,394 | https://en.wikipedia.org/wiki/Nearby%20Share | Nearby Share was a functionality developed by Google that allows data to be transferred between devices via Bluetooth, Wi-FI Direct or Internet. In 2024, it was merged into Samsung's Quick Share. It was available for Android, ChromeOS and Microsoft's Windows. It was first released on August 4, 2020.
Nearby Share is not to be confused with Microsoft's similarly-named "nearby sharing" feature, which is only available for PCs running Windows 10 or later and uses Microsoft's own proprietary protocol.
History
Before Nearby Share, Google launched Android Beam in 2011. By 2017, ComputerWorld included Android Beam in a list of "once-trumpeted features that quietly faded away", observing that "despite the admirable marketing effort, Beam never quite worked particularly well, and numerous other systems for sharing stuff proved to be simpler and more reliable."
Nearby Share was officially released for devices running Android Marshmallow and later on August 4, 2020. The program worked much like Apple's AirDrop, allowing users to select "Nearby Share" on the share menu and then to wait for a nearby phone to appear.
In June 2021 with the rollout of ChromeOS 91, Nearby Share was released for ChromeOS with the same features and options as the Android version. During CES 2022, Google announced Nearby Share for Windows. On March 31, 2023, the beta version of the Nearby Share App was released for Windows PCs allowing cross-platform file transfers.
In January 2024, Google and Samsung announced that Nearby Share and Quick Share would merge into one unified app, under the name Quick Share.
Usage
On Android and ChromeOS, Nearby Share is enabled by going to Connected Devices > Connection preferences > Nearby Share (or Google > Devices & sharing > Nearby Share) in the settings app and enabling "Use Nearby Share." On Windows, Nearby Share is downloaded from android.com. Once the setup program is done installing Nearby Share, or from the Nearby Share settings menu Android, the user will be able to choose who is able to see their device. The available options are:
Everyone
Contacts
Your devices
Hidden
When sharing a file via Nearby Share, the user will be presented with a list of available devices to share with. Choosing a device from the list sends a prompt to the recipient that requires them to confirm the transfer. When sharing amongst devices linked to the same Google Account, it is not required to wake the receiving devices or confirm the file transmission.
Nearby Share allows for the sharing of files and links, such as images, videos, text, contact info, directions, YouTube videos, and other data. It uses Bluetooth, Bluetooth Low Energy, WebRTC, and peer-to-peer Wi-Fi to share content. It can be configured to only share content offline, restricting it to Bluetooth only operation.
Availability
Nearby Share is available on Android 6 and later, ChromeOS 91 and later, and Windows 10 and later. On Windows, Nearby Share must be installed manually, as opposed to its implementation on Android and ChromeOS, where it is a part of the operating system and does not need to be installed separately. Windows devices must have both Bluetooth and Wi-Fi to be able to run Nearby Share. Windows on ARM devices are not supported.
See also
AirDrop, a similar functionality by Apple
Briar, an independent copyleft app for Android
SHAREit, a P2P file sharing platform
Wi-Fi Direct, a similar technology
Zapya, proprietary file transfer over Wi-Fi app
References
External links
Windows app
Android (operating system)
Google Chrome
File transfer protocols
Bluetooth | Nearby Share | [
"Technology"
] | 734 | [
"Wireless networking",
"Bluetooth"
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64,753,670 | https://en.wikipedia.org/wiki/Wastewater%20surveillance | Wastewater surveillance is the process of monitoring wastewater for contaminants. Amongst other uses, it can be used for biosurveillance, to detect the presence of pathogens in local populations, and to detect the presence of psychoactive drugs.
One example of this is the use of wastewater monitoring to detect the presence of the SARS-CoV-2 virus in populations during the COVID-19 pandemic. In one study, wastewater surveillance showed signs of SARS-CoV-2 RNA before any cases were detected in the local population.
Later in the pandemic, wastewater surveillance was demonstrated to be one technique to detect SARS-CoV-2 variants and to monitor their prevalence over time. Comparison between case based epidemiological records and deep-sequenced wastewater samples validated that the composition of the virus population in the wastewater is in strong agreement with the virus variants circulating in the infected population. Following the 2022-23 reopening surge of COVID-19 cases in China, airplane wastewater surveillance began to be employed as a less intrusive method of monitoring for potential variants of concern arising within specific countries and regions.
At the request of the US Centers for Disease Control, the National Academies of Sciences, Engineering, and Medicine revealed, in a January 2023 report, its vision for a national wastewater surveillance system. Such a system would, according to the report committee, remove geographical inequities in the identification of future SARS-CoV-2 variants, influenza strains, antibiotic resistant bacteria, and other potential threats. Nationwide wastewater surveillance would likewise be combined with wastewater collection at other early-warning "sentinel sites", such as zoos and international airports.
The European Union identified wastewater surveillance as "a cost effective, rapid and reliable source of information on the spread of SARS-CoV-2 in the population and that it can form a valuable part of an increased genomic and epidemiological surveillance" and proposes to extend the urban wastewater surveillance to poliovirus, influenza, emerging pathogens, contaminants of emerging concern, antimicrobial resistance and any other public health parameters that are considered relevant by the Member States.
See also
Wastewater-based epidemiology
References
Epidemiology
Sewerage
Surveillance | Wastewater surveillance | [
"Chemistry",
"Engineering",
"Environmental_science"
] | 464 | [
"Water pollution",
"Sewerage",
"Environmental engineering",
"Epidemiology",
"Environmental social science"
] |
64,754,126 | https://en.wikipedia.org/wiki/Quinoline%20alkaloids | Quinoline alkaloids are naturally occurring chemical compounds from the group of alkaloids, which are chemically derived from quinoline. Some quinoline alkaloids show antiseptic, convulsive or antineoplastic effects.
Examples
Alkaloids with a quinoline partial structure are widespread and are usually further subdivided according to their occurrence and biogenetic origin. Among the quinoline alkaloids are the cinchona alkaloids quinine and quinidine, which are important due to their therapeutic potential, furthermore cinchonine and cinchonidine, as well as some furoquinoline alkaloids and acridine alkaloids. Strychnine and brucine, alkaloids of the nux vomica, which have a hydrogenated quinoline system, are also counted among the quinoline alkaloids. Also nitramarine (1-(2-quinolinyl)-β-carboline) belongs to the quinoline alkaloids.
Occurrence
The quinoline alkaloids are mainly found in plants, as in Rutaceae and Rubiaceae, but also in microorganisms and animals. Quinoline is furthermore comprised as a partial structure in the redox factor PQQ (pyrroloquinoline quinone) and in quinoenzymes.
Biosynthesis
Biogenetically, there are several proven pathways for the formation of the quinoline system in plants. Tryptophane as well as anthranilic acid can act as a precursor. The second precursor molecule is either a hemiterpene or a monoterpene (e.g. secologanine in cinchona alkaloids).
Literature
Alkaloids | Quinoline alkaloids | [
"Chemistry"
] | 373 | [
"Organic compounds",
"Biomolecules by chemical classification",
"Natural products",
"Alkaloids"
] |
64,754,367 | https://en.wikipedia.org/wiki/Cat%20Hobaiter | Catherine (Cat) Hobaiter is a British-Lebanese primatologist focusing on social behaviour in wild chimpanzees and involved in long-term studies of chimpanzees in the Budongo Forest Reserve in Uganda and the MoyenBafing National Park in Guinea. She is particularly interested in the role gestures play in communication. She is a Reader at the University of St Andrews.
Career
Hobaiter is based at the University of St Andrews but spends considerable amounts of time on field research in Uganda. She gained tenure in 2013.
Her undergraduate degree started her interest in comparative behaviour and contact with Richard Byrne from St Andrews University led to her first four months fieldwork looking for baboons in Budongo Forest Reserve, working from the Budongo Conservation Field Station. She soon changed to studying wild gorillas and chimpanzees, and especially the Sonso chimpanzee group at the reserve that has been accustomed to humans since the 1990s.
Her work has studied the use of gestures in communication by great apes, especially chimpanzees, in the wild. This requires filming gestures for detailed analysis and, prior to her work, this had been undertaken primarily in zoos or wildlife parks. Her studies have gradually developed a catalogue of around 80 gestures that form a language common to several groups of wild apes, measured in terms of 'apparently satisfactory outcomes' (ASO) after assessing many records. A citizen science project showed that some of the gestures are also understood by humans. Hobaiter is also involved in habituating a second group of chimpanzees in the Budongo Forest, the Waibira group, which will allow wider comparisons of the use of gestures for communication in the wild.
The film recordings also revealed other aspects of chimpanzee life, such as adoption of new tools for drinking.
Her research now focuses on how human language evolved, through studying the use of gestures in both humans and great apes. The idea that a gestural system could have evolved into a spoken language as used by humans, is controversial but study of the gestures used by children before they can speak, as well as gestures widespread among chimpanzees can provide information to inform the debate.
Publications
She has been the author or co-author of over 65 scientific publications, including:
Catherine Hobaiter (2020) The importance of being in situ Current Biology 30 R199-R201
Juan Olvido Perea-García, Mariska E. Kret, Antónia Monteiro, Catherine Hobaiter (2019) Scleral pigmentation leads to conspicuous, not cryptic, eye morphology in chimpanzees Proceedings of the National Academy of Sciences of the United States of America 116 19248–19250
Andrea Knox, Joey Markx, Emma How, Abdul Azis, Catherine Hobaiter, Frank J.F. van Veen, Helen Morrogh-Bernard (2019) Gesture use in communication between mothers and offspring in wild orang-utans (Pongo pygmaeus wurmbii) from the Sabangau peat-swamp forest, Borneo International Journal of Primatology 40 393–416
Byrne, R. W., Cartmill, E., Genty, E., Graham, K. E., Hobaiter, C. & Tanner, J. (2017) Great ape gestures: intentional communication with a rich set of innate signals. Animal Cognition 20 755-769
Gruber, T., Poisot, T., Zuberbuehler, K., Hoppitt, W. & Hobaiter, C. (2015) The spread of a novel behaviour in wild chimpanzees: new insights into the ape cultural mind. Communicative and Integrative Biology 8 e1017164.
Wilson, M. L., Boesch, C., Fruth, B., Furuichi, T., Gilby, I. C., Hashimoto, C., Hobaiter, C., Hohmann, G., Itoh, N., Koops, K., Lloyd, J. N., Matsuzawa, T., Mitani, J. C., Mjungu, D. C., Morgan, D., Muller, M. N., Mundry, R., Nakamura, M., Pruetz, J., Pusey, A. E. & 10 others (2014) Lethal aggression in Pan is better explained by adaptive strategies than human impacts Nature. 513 414-417
Hobaiter, C. & Byrne, R. W., (2014) The meanings of chimpanzee gestures Current Biology 24 1596-1600
Hobaiter, C. & Byrne, R. W., (2011) The gestural repertoire of the wild chimpanzee Animal Cognition 14 745-767
Genty, E. J. P., Breuer, T., Hobaiter, C. L. & Byrne, R. W., (2009) Gestural communication of the gorilla (Gorilla gorilla): repertoire, intentionality, and possible origins Animal Cognition 12 527-546
Awards and recognition
In 2016 she became vice president for Communications, International Primatological Society.
Hobaiter was the guest on the BBC Radio 4 programme The Life Scientific in May 2018.
In August 2020, Hobaiter was a guest on the BBC Radio 4 programme The Infinite Monkey Cage to discuss how understanding of chimpanzees has changed since the 1960s.
Personal life
Catherine (Cat) Hobaiter initially lived in Lebanon, returning to the UK when she was a child. She studied B. Sc. Biological Sciences at the University of Edinburgh. After graduating she worked in commercial project management for a short time but then obtained funding for the doctoral research that marked the start of her academic career. Her PhD was awarded by University of St Andrews in 2011.
References
External links
Living people
Ethologists
Women ethologists
21st-century British zoologists
Animal cognition writers
British science communicators
Academics of the University of St Andrews
Alumni of the University of Edinburgh
21st-century British women scientists
Women primatologists
Primatologists
Year of birth missing (living people)
Alumni of the University of St Andrews | Cat Hobaiter | [
"Biology"
] | 1,306 | [
"Ethology",
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64,755,799 | https://en.wikipedia.org/wiki/Stable%20and%20unstable%20stratification | Stable stratification of fluids occurs when each layer is less dense than the one below it. Unstable stratification is when each layer is denser than the one below it.
Buoyancy forces tend to preserve stable stratification; the higher layers float on the lower ones. In unstable stratification, on the other hand, buoyancy forces cause convection. The less-dense layers rise though the denser layers above, and the denser layers sink though the less-dense layers below. Stratifications can become more or less stable if layers change density. The processes involved are important in many science and engineering fields.
Destablization and mixing
Stable stratifications can become unstable if layers change density. This can happen due to outside influences (for instance, if water evaporates from a freshwater lens, making it saltier and denser, or if a pot or layered beverage is heated from below, making the bottom layer less dense). However, it can also happen due to internal diffusion of heat (the warmer layer slowly heats the adjacent cooler one) or other physical properties. This often causes mixing at the interface, creating new diffusive layers (see photo of coffee and milk).
Sometimes, two physical properties diffuse between layers simultaneously; salt and temperature, for instance. This may form diffusive layers or even salt fingering, when the surfaces of the diffusive layers become so wavy that there are "fingers" of layers reaching up and down.
Not all mixing is driven by density changes. Other physical forces may also mix stably-stratified layers. Sea spray and whitecaps (foaming whitewater on waves) are examples of water mixed into air, and air into water, respectively. In a fierce storm the air/water boundary may grow indistinct. Some of these wind waves are Kelvin-Helmholtz waves.
Depending on the size of the velocity difference and the size of the density contrast between the layers, Kelvin-Helmholtz waves can look different. For instance, between two layers of air or two layers of water, the density difference is much smaller and the layers are miscible; see black-and-white model video.
Applications
Planetary science
Stratification is commonly seen in the planetary sciences.
Solar energy passes as visible radiation through the air, and is absorbed by the ground, to be re-emitted as heat radiation. The lower atmosphere is therefore heated from below (UV absorption in the ozone layer heats that layer from within). Outdoor air is thus usually unstably stratified and convecting, giving us wind. Temperature inversions are a weather event which happens whenever an area of the lower atmosphere becomes stably-stratified and thus stops moving.
Oceans, on the other hand, are heated from above, and are usually stably stratified. Only near the poles does the coldest and saltiest water sink. The deep ocean waters slowly warm and freshen through internal mixing (a form of double diffusion), and then rise back to the surface.
Examples:
Stratification (water)
Ocean stratification, the formation of water layers based on temperature and salinity in oceans
Lake stratification, the formation of water layers based on temperature, with mixing in the spring and fall in seasonal climates.
Atmospheric instability
Atmospheric stratification, the dividing of the upper reaches of the Earth's atmosphere into stably-stratified layers
Atmospheric circulation, caused by the unstable stratification of the atmosphere
Thermohaline circulation, circulation in the oceans despite stable stratification.
Stratified flows (such as the flow through the Straits of Gibraltar)
Engineering
In engineering applications, stable stratification or convection may or may not be desirable. In either case it may be deliberately manipulated.
Stratification can strongly affect the mixing of fluids, which is important in many manufacturing processes.
Underfloor heating deliberately creates unstable stratification of the air in a room.
Passive cooling relies on selectively encouraging and disrupting stable stratification to cool rooms.
References
Fluid dynamics | Stable and unstable stratification | [
"Chemistry",
"Mathematics",
"Engineering"
] | 836 | [
"Functions and mappings",
"Chemical engineering",
"Mathematical objects",
"Vertical distributions",
"Mathematical relations",
"Piping",
"Fluid dynamics"
] |
64,755,932 | https://en.wikipedia.org/wiki/Solar%20gravitational%20lens | A solar gravitational lens or solar gravity lens (SGL) is a theoretical method of using the Sun as a large lens with a physical effect called gravitational lensing. It is considered one of the best methods to directly image habitable exoplanets.
The solar gravitational lens is characterized by remarkable properties: it offers brightness amplification of up to a factor of ~ (at ) and extreme angular resolution (~ arcsec).
Albert Einstein predicted in 1936 that rays of light from the same direction that skirt the edges of the Sun would converge to a focal point approximately 542 AUs from the Sun. A probe positioned at this distance from the Sun could use it as a gravitational lens for magnifying distant objects on the opposite side of the Sun. The probe's location could shift around as needed to select different targets relative to the Sun. In 1979, Von Eshleman was the first author proposing to use the Sun as a large lens.
The Sun's gravitational field bends light more prominently the closer it gets to the Sun. Light rays passing on opposite sides of the Sun meet at a focal point, forming a series of points along a line that extends from the star through the Sun's center. With the solar corona having an active and dynamic atmosphere, the beams of light passing close to the Sun are affected by the particles of the atmosphere.
A probe called SETIsail and later FOCAL was proposed to the ESA in 1993, but is expected to be a difficult task. If a probe does pass 542 AU, magnification capabilities of the lens will continue to act at farther distances, as the rays that come to a focus at larger distances pass further away from the distortions of the Sun's corona.
In 2020, NASA physicist Slava Turyshev presented his idea of direct multi-pixel imaging and spectroscopy of an exoplanet with a solar gravitational lens mission. The lens could reconstruct the exoplanet image with ~25 km-scale surface resolution in 6 months of integration time, enough to see surface features and signs of habitability. His proposal was selected for the Phase III of the NIAC 2020 (NASA Institute for Advanced Concepts). Turyshev proposes to use realistic-sized solar sails (~16 vanes of 103 m2) to achieve the needed high velocity at perihelion (~150 km/sec), reaching 547 AU in 17 years.
See also
Einstein ring
References
Astronomical imaging
Space exploration
Exoplanets
Space probes
NASA programs
Proposed telescopes | Solar gravitational lens | [
"Astronomy"
] | 512 | [
"Space exploration",
"Outer space"
] |
64,756,030 | https://en.wikipedia.org/wiki/Graph%20Theory%2C%201736%E2%80%931936 | Graph Theory, 1736–1936 is a book in the history of mathematics on graph theory. It focuses on the foundational documents of the field, beginning with the 1736 paper of Leonhard Euler on the Seven Bridges of Königsberg and ending with the first textbook on the subject, published in 1936 by Dénes Kőnig. Graph Theory, 1736–1936 was edited by Norman L. Biggs, E. Keith Lloyd, and Robin J. Wilson, and published in 1976 by the Clarendon Press. The Oxford University Press published a paperback second edition in 1986, with a corrected reprint in 1998.
Topics
Graph Theory, 1736–1936 contains copies, extracts, and translations of 37 original sources in graph theory, grouped into ten chapters and punctuated by commentary on their meaning and context. It begins with Euler's 1736 paper "Solutio problematis ad geometriam situs pertinentis" on the seven bridges of Königsberg (both in the original Latin and in English translation) and ending with Dénes Kőnig's book Theorie der endlichen und unendlichen Graphen. The source material touches on recreational mathematics, chemical graph theory, the analysis of electrical circuits, and applications of graph theory in abstract algebra. Also included are background material and portraits on the mathematicians who originally developed this material.
The chapters of the book organize the material into topics within graph theory, rather than being strictly chronological. The first chapter, on paths, includes maze-solving algorithms as well as Euler's work on Euler tours. Next, a chapter on circuits includes material on knight's tours in chess (a topic that long predates Euler), Hamiltonian cycles, and the work of Thomas Kirkman on polyhedral graphs. Next follow chapters on spanning trees and Cayley's formula, chemical graph theory and graph enumeration, and planar graphs, Kuratowski's theorem, and Euler's polyhedral formula. There are three chapters on the four color theorem and graph coloring, a chapter on algebraic graph theory, and a final chapter on graph factorization. Appendices provide a brief update on graph history since 1936, biographies of the authors of the works included in the book, and a comprehensive bibliography.
Audience and reception
Reviewer Ján Plesník names the book the first ever published on the history of graph theory, and although Hazel Perfect notes that parts of it can be difficult to read, Plesník states that it can also be used as "a self-contained introduction" to the field, and Edward Maziarz suggests its use as a textbook for graph theory courses. Perfect calls the book "fascinating ... full of information", thoroughly researched and carefully written, and Maziarz finds inspiring the ways in which it describes serious mathematics as arising from frivolous starting points. Fernando Q. Gouvêa calls it a "must-have" for anyone interested in graph theory, and Philip Peak also recommends it to anyone interested more generally in the history of mathematics.
References
External links
Graph theory
Books about the history of mathematics
1976 non-fiction books | Graph Theory, 1736–1936 | [
"Mathematics"
] | 635 | [
"Discrete mathematics",
"Mathematical relations",
"Graph theory",
"Combinatorics"
] |
64,756,604 | https://en.wikipedia.org/wiki/The%20Elevator%20Museum | The Elevator Museum is a museum and non-profit 501(c)(3) organization in Massachusetts, United States.
History
In 2011, The Elevator Historical Society was opened in Long Island City, New York by Patrick Carr a lifetime collector of elevator history with an exhibit of over 4000 elevator parts and components. Due to a lack of funding from the industry it elected to close in 2016 and transfer the collection to a group in Boston. The exhibit items were relocated to a temporary location at The International Union of Elevator Constructors Local 4 Union Hall in 2017, and combined with an extensive collection of artifacts by Stephen K. Comley and his father James F. Comley.
The Comleys funded a move to the Haverhill location, then assembled a board of advisors and directors, and in 2019 received non-profit status for The Elevator Museum.
References
External links
Museum website
2019 establishments in Massachusetts
Museums established in 2019
Buildings and structures in Haverhill, Massachusetts
Museums in Essex County, Massachusetts
Industry museums in Massachusetts
Transportation museums in Massachusetts
Technology museums in the United States
Elevators | The Elevator Museum | [
"Engineering"
] | 214 | [
"Building engineering",
"Elevators"
] |
64,758,147 | https://en.wikipedia.org/wiki/HPG80 | hPG80 refers to the extracellular and oncogenic version of progastrin. This name first appeared in a scientific publication in January 2020. Until that date, scientific publications only mention 'progastrin', without necessarily explicitly specifying whether it is intracellular (in the context of digestion) or extracellular (circulating and detectable in plasma) in the tumor pathological setting.
For more clarity, the remainder of this article uses exclusively the name hPG80 to refer to extracellular progastrin.
A link between this protein and cancer has been known for more than 30 years. hPG80 is involved in most of the biological functions that ensure the existence of cancer. The peptide is secreted by tumor cells and found in the plasma of cancer patients from early stages. It then has functions that are independent of digestion and totally different from progastrin and its only role as an intracellular precursor of gastrin.
Terminology
In the name hPG80, the "h" describes the human species: human; "PG" is a common script for the progastrin protein and the number 80 corresponds to the size of the protein: 80 amino acids.
The name hPG80 was thus proposed in the publication resulting from the work of Professor Benoît You under the management of Dominique Joubert and Alexandre Prieur in order to remove ambiguities between the intracellular version of the protein (in the function of digestion) and its extracellular version of the protein (in the case of cancer patients) which is no longer, despite its name, the precursor of gastrin.
Moreover, the existence of a phonetically identical peptide, the Pro-Gastrin Releasing Peptide (proGRP), accentuated a possible confusion around the name progastrin and the need for a specific name.
Chronology of scientific discoveries on hPG80
1990: hPG80 is secreted by pancreatic cancer cells.
1993 - 1994: hPG80 is secreted by ovarian and colon cancer cells.
1996 - 1997: hPG80 is identified as necessary for the proliferation and tumorigenesis of colon cancer cells.
2000 - 2001: The GAST gene is a target of the β-catenin/Tcf4 pathway. The presence of hPG80 is demonstrated in the plasma of colorectal cancer patients.
2003: hPG80 is involved in the dissociation regulation of adherent and tight junctions. Src mediates the effects of hPG80 on cell growth.
2005: Ras and β-catenin/Tcf4 pathways induce synergistic activation of the GAST gene, contributing to possible neoplastic progression.
2007: Inhibition of hPG80 expression inhibits the Wnt/β-catenin pathway inducing decreased growth and tumor differentiation in intestinal tumor models.
2012: p53 gene mutation increases hPG80-dependent colonic proliferation and cancer formation.
2014: hPG80 is identified as a new pro-angiogenic factor.
2016: Autocrine secretion of hPG80 promotes survival and self-renewal of stem cells in colon cancer.
2017: The use of antibodies directed against hPG80 to target the Wnt pathway and cancer stem cells represents a new therapeutic track for cancer.
2020: hPG80 is detected in the plasma of patients with 11 different types of cancer. An association between longitudinal variations in hPG80 levels and the efficacy of anti-cancer treatments has been demonstrated.
Role in cancer
Through a variety of mechanisms, all crucial for tumor growth and survival, research has demonstrated the major role that hPG80 plays in tumor initiation and progression, generally using colorectal cancer as a model. Bardram was the first to hypothesize the presence of hPG80 in the early stages of the disease. He evaluated the presence of hPG80 and its maturation products in the serum of patients with Zollinger-Ellison syndrome. This work showed that hPG80 measurement more accurately reflected tumor than the conventional measurement of amide gastrin. Indeed, hPG80 is more than 700 times more abundant than amide gastrin in colorectal tumors.
In the early 90s, it was shown that hPG80 was not fully matured in human colon cancer cell lines and, more importantly, that it was secreted by in vitro cells. These observations led to the study of autocrine and paracrine function of hPG80 in tumor cells. Generally, it has been shown that hPG80 does not mature properly in cancer cells, particularly in colorectal cancer, because maturation enzymes are either absent or non-functional.
In 1996, it was demonstrated that GAST gene expression is required for human colon cancer cell tumorigenesis. 60 to 80% of colon cancers express the GAST gene.
Through different experimental configurations, alteration of the GAST gene or neutralization of hPG80 resulted in a decrease in the number of tumors in mice with a tumor predisposition (mutation on the APC gene). Conversely, a significant increase in tumor formation was observed in mice overexpressing progastrin and treated with azoxymethane (AOM), a chemical carcinogen.
Pro-angiogenic factor
When a tumor develops, its need for oxygen and nutrients causes creation of new blood vessels. This process is called neo-angiogenesis. In 2015, hPG80 was shown to be a pro-angiogenic factor. Indeed, hPG80 stimulates endothelial cells proliferation and migration and increases their ability to form capillary-like structures in vitro. Blocking the production of hPG80 (with shRNA) in xenograft cells in nude mice reduces tumor neovascularization.
Anti-apoptotic factor
Treatment of intestinal epithelial cells with hPG80 results in a significant loss of caspase 9 and caspase 3 activation and a decrease in DNA fragmentation. Therefore, the effect of hPG80 on cell survival results from both increased proliferation and decreased apoptosis.
Regulation of cell junctions
Cell migration is based on their ability to become independent of adjacent cells. Intercellular contacts integrity is essential for electrolyte uptake regulation as well as for tumor metastasis prevention. In 2003, it was demonstrated that blocking hPG80 secretion by an antisense construction directed against progastrin mRNA allows restoration of membrane localization of tight and adherent junctions constituent proteins in a human colorectal carcinoma cell line DLD-1. hPG80 thus plays a role on cell contacts integrity.
Role in cancer stem cells
Cancer stem cells (CSCs) constitute a small proportion of the tumor, usually between 1 and 5%. But they are essential for tumor survival because they act as a "reactor". Giraud and al. have demonstrated the major role played by hPG80 in CSCs. These authors have shown that hPG80 expression is strongly increased in colorectal cancer cells cultured under conditions where CSCs are enriched. They then showed that hPG80 was able to regulate CSCs frequency (survival and self-renewal) in vitro and in vivo. Subsequently, Prieur and al. demonstrated that when a neutralizing antibody is added to a cell culture or when human colorectal cancer cells implanted mice are treated in vivo with such an antibody, CSCs frequency is decreased in the same proportions. These two scientific articles clearly show that hPG80 is a survival factor for CSCs. Moreover, hPG80 inhibition would induce CSC differentiation, opening the possibility of a differentiation therapy rather than a classical anti-proliferative therapy. Its main function is to help CSCs survive and spread to form metastases, which probably explains why this peptide can be considered as a potential predictive marker for the presence of liver metastasis in colorectal cancer.
hPG80 and oncogenic signaling pathways
Wnt and K-Ras
The first event leading to colon cancer is in 80 to 90% of cases a constitutive activation of the Wnt/β-catenin oncogenic pathway induced by mutations in the APC (Adenomatous polyposis coli) coding gene or the β-catenin coding gene. Mutations induction into normal intestinal stem cells is sufficient to trigger tumorigenesis. GAST gene which encodes hPG80 is activated by the Wnt oncogenic pathway. It is a downstream target of the β-catenin/Tcf-4 signaling pathway.
Demonstration of the link between hPG80 and an oncogenic pathway has been described for K-Ras. Cell lines and colon cancer tissues with K-Ras mutations all had significantly higher levels of GAST mRNA than wild type K-Ras. K-Ras effects on GAST expression are produced by activation of the Raf-MEK-ERK signal transduction pathway, final step being activation of the GAST gene promoter.
Since both K-Ras and the Wnt pathway induce GAST expression, the hypothesis of a possible cooperation between these two pathways to regulate hPG80 expression was investigated. Chakadar and al. found significant synergistic stimulation of the GAST gene promoter (by a factor of 25–40) by a combination of oncogenic β-catenin and K-Ras overexpression. Activation of the GAST gene promoter was also shown to be dependent on other signalling signals: enhanced or suppressed by co-expression of wild-type SMAD4 or by a dominant negative mutant of SMAD4, respectively, and abrogated by inhibition of PI3K. Thus, constitutive activation of the Wnt pathway, considered to be at the onset of tumorigenesis in the colon, and the K-Ras oncogene, present in 50% of human colorectal tumors, synergistically stimulate the production of hPG80, a tumorigenesis promoter. Tumorigenesis induced by activation of the Wnt pathway is partially dependent on hPG80.
SRC, PI3K/Akt, NF-kB and Jak/Stat
The oncogene pp60 (c-Src) is activated in colon cancer cells and leads to increased amounts of hPG80. This means that hPG80 production, which occurs during early tumorigenesis, could play a role in this activation, which is known as an early event in colon tumorigenesis. The PI3K/Akt pathway, which is particularly involved in proliferation, is also activated by hPG80. NF-kappaB is another important signaling messenger regulated by hPG80. Its involvement in mechanisms responsible for the anti-apoptotic effect of hPG80 has been demonstrated in pancreatic cancer cells in vitro and in vivo in mice overexpressing the GAST gene. JAK2 (Janus-activated kinase 2), STAT3 and kinases increases regulated by extracellular signals have also been observed in the colon mucosa of hGAS mice.
NOTCH
It has been shown that colon tumor cells which do not express hPG80 return to a "normal" state. This is due to the fact that when the Wnt pathway is inactivated, the JAG1 gene is repressed, inducing inactivation of the Notch pathway which plays a major role in the acquisition of a differentiated cell phenotype.
p-53
In 2012, the P53 gene mutation was shown to increase hPG80-dependent colon cells proliferation and colon cancer formation in mice.
hPG80 receptor
An identification of the hPG80 receptor has been the subject of several studies in recent years. However, hPG80 receptor identity remains a real issue in the scientific community. The receptor can activate a number of signaling pathways, either directly or indirectly, which is rather unusual for a receptor. This could indicate a peculiarity of this receptor and why it is difficult to identify it. The unidentified hPG80 receptor transduces a progastrin signal via various intracellular intermediates known to be involved in tumorigenesis.
High affinity binding sites have been described for the first time in intestinal epithelial cells using recombinant human progastrin iodine. Affinity was in the range of 0.5-1 nM, which is receptor compatible. When biotinylated progastrin binding was evaluated by flow cytometry, strong and specific binding of progastrin to certain cell lines (IEC-6, IEC-18, HT-29, COLO320) was also detected. A specificity of binding was confirmed by competition with cold, unlabelled hPG80, but not with carboxy-terminal glycine-containing gastrin or amidated gastrin-17. Binding was not influenced by the presence of the classical CCK-2 receptor.
It is clear from these two studies that there is a binding site/receptor for hPG80 that is distinct from binding to gastrin-17 amidated and to gastrin 17 with carboxy-terminal glycine (G17-Gly). The sequence of hPG80 interacting with this receptor is likely located in the last 26 amino acid residues of hPG80 carboxy-terminal end, which have been shown to be sufficient for its function. However, this putative receptor identity is unknown.
One candidate is Annexin A2, identified as being able of binding progastrin and derived peptides. Annexin A2 is a partial mediator of the effect of progastrin/gastrins. In particular, Annexin A2 mediates NF-kappaB upregulation and β-catenin in response to progastrin in mice and HEK-293 cells. In addition, annexin A2 may be involved in progastrin-dependent clathrin endocytosis. However, progastrin affinity for Annexin A2 is not what would be expected for a specific receptor. And, although Annexin A2 plays a role in progastrin functions, it does not fit a receptor function.
Another candidate is the G protein-coupled receptor 56 (GPCR56), expressed on both colon stem cells and cancer cells. While human recombinant hPG80 promotes in vitro growth and survival of wild mice colon organoids, those from GPCR56-deficient mice (GPCR56-/-) are resistant to hPG80. However, although hPG80 has been shown to bind to cells expressing GPCR56, authors did not provide direct evidence of a hPG80 bound to GPCR56 itself. GPCR56 is a good candidate, but evidence that it is hPG80 receptor is to this day not established.
Clinical Applications
hPG80 through various mechanisms can be considered as a major promoter of tumorigenesis. hPG80 is found in the plasma of cancer patients and its neutralization induces tumor reversion.
Screening
Universal biomarker
Colorectal cancer is not the only type of cancer to express hPG80. Its expression has also been demonstrated in ovarian cancers, liver tumors and pancreatic tumors. Thus, several types of tumors express the unmatured peptide. hPG80 can be detected and quantified in the blood of cancer patients. A first demonstration has been made in colorectal cancer showing an increase of hPG80 and non-amide gastrin levels in plasma in these patients compared to a control series (healthy individuals). In addition, an hPG80 increase has been observed in patients with adenomatous polyps. hPG80 is therefore expressed at all stages by the tumor, from early stages to metastasis.
Multi-cancer detection
hPG80 is found in different tumor types and secreted in vitro by certain cancer cells. A study has shown its presence in the blood of patients with 11 different types of cancer: breast cancer, colorectal cancer, stomach/esophageal cancer, kidney cancer, liver cancer, non-small cell lung cancer, skin melanoma, ovarian cancer, pancreatic cancer, prostate cancer and uterine cancer (endometrial/cervical).
hPG80 in residual disease surveillance and response to therapy.
Pre- and post-operative plasma assays of hPG80 in colorectal cancer patients show that hPG80 presence reflects tumor production.
It has been observed that hPG80 concentrations are increased in patients at risk of developing colorectal carcinoma. In addition, an increase in hPG80 has been observed in hyperplastic polyps that have progressed to cancer.
hPG80 may also be a biomarker of liver metastasis in colorectal cancer.
In addition, You and al. observed a decrease in hPG80 levels after surgery in a patients cohort with gastrointestinal cancers with peritoneal involvement treated with post-operative chemotherapy and cytoreductive surgery.
In addition, earlier detection of small lesions and monitoring of recurrence can be improved by measuring hPG80 levels as a complementary blood biomarker in a cohort of patients with hepatocellular carcinoma treated with local or systemic therapies (Fig. 3). Measured hPG80 levels are relevant in patients for whom alpha-fetoprotein (AFP) is below 20 ng/ml, an established threshold in clinical practice. Depending on disease management, patients in remission have lower levels of hPG80 than those in whom the cancer is still active.
Target to fight cancer
Antibody therapy
To date, no drug is able to target CSCs. Humanized anti-hPG80 antibodies, alone or in combination with chemotherapy, appears to be a promising approach. The use of anti-hPG80 antibodies has also been discussed as a potential treatment in colorectal cancer patients with a mutation in the KRAS gene. Targeting of hPG80 with the humanized anti-hPG80 antibody has been shown:
1. a decrease in the self-renewal capacity of CSCs of various origins;
2. prolongation of in vitro and in vivo chemosensitivity and delayed relapse after treatment of T84 xenografted mouse cells;
3. decreased tumor burden and increased cell differentiation in the remaining tumors in transgenic mice developing Wnt-induced intestinal neoplasia.
This has recently been confirmed for ovarian, breast, esophageal, liver and gastric cancers making this therapeutic antibody a potential multi-cancer drug.
Sensitization to radiotherapy
It has been shown that hPG80 is a radioresistant factor that can be targeted to sensitize rectum radiation-resistant cancers. hPG80 decreased expression increases sensitivity to irradiation in colorectal cancer cell lines leading to increased radiation-induced DNA damage and apoptosis. In the same lineage, hPG80 targeting also results in radiation-induced survival pathways inhibition, Akt and ERK.
References
Oncology
Biomarkers | HPG80 | [
"Biology"
] | 3,908 | [
"Biomarkers"
] |
64,758,384 | https://en.wikipedia.org/wiki/Adaptive%20machine | An adaptive machine is a category of industrial machinery characterized by the ability to adapt itself to the product to be produced, e.g. to move individual products through the manufacturing, assembly, inspection, packaging and other process stations required to produce them.
Examples of intelligent adaptive capabilities
Detecting the size and shape of products in a current production batch and automatically adapting the distance of the actuators used to clamp them and to transport them through the processing line
Adapting the route a product takes through a processing line based on the specifications of the product; each product can take its own individual route through a production line and only stop at processing stations where it actually needs processing. Unnecessary stations are by-passed, via an alternate route or just passed through. This is in stark contrast to fixed-indexing systems such as belt and chain conveyors or round dials that still represent the majority of installed manufacturing equipment.
Exemplary non-characteristics
Using a multitude of work-piece holders specific to each single product variant
Operator intervention for mechanical change-over (e.g. exchanging mechanical cams)
Design approach
At first glance, the adaptive capabilities are rooted in software. But a second look reveals that machines handle physical products. For doing so machines need a proper mechanical design as well as a proper electrical design to power the mechanical movements. An adaptive machine is best designed by applying an interdisciplinary mechatronic design approach where mechanics, electrics and software as well as their interfaces and interactions are considered holistically.
Purpose
The primary function of an adaptive machine is to make production more flexible by enable greater product variety (e.g. with respect to product size and shape) and smaller batches. The ultimate goal of an adaptive machine is mass customization, and the holy grail of economical batch size, one product, made to customer order rather than for stock. As far back as 1997, the Harvard Business Review identified four approaches to mass customization, one being ‘adaptive customizers’ in which standard products are adapted by the customer. The adaptive machine is actually more representative of HBR’s collaborative and cosmetic approaches, in which products and/or packaging are customized during production.
This description was provided by the Frost & Sullivan research firm in October 2017.
Core enabling technologies
The concept of the adaptive machine relies on the following core technologies to enable adaptability and to achieve high levels of flexibility.
Track technology
Robots: One complementary technology is the industrial robot, which by definition possesses the same programmable flexibility. Of particular interest is the ability of both robots and track systems to operate safely along with humans in a collaborative environment. This recent development allows for a combination of manual and automated assembly tasks, maintenance and materials replenishment without stopping production.
Machine vision: Machine vision can play a pivotal role when integrated into an adaptive machine. Vision can identify individual shuttles and their contents in order to guide them to the appropriate workstations. Vision has long been used to automate robot guidance, inspection, orientation and related tasks.
Internet of Things and e-commerce technologies: given the adaptive machine's flexibility to respond to consumer demand generation these technologies are complementary, providing the connection between internal production resources and commercial systems in a manufacturer's digital business model
Terminology and history
The term has been attributed to B&R Industrial Automation, where it is used in their product descriptions, white papers and use cases. In the packaging sector the evolution of machine technology has been roughly categorized by OMAC as follows:
Gen 1 – mechanically driven machines
Gen 2 – servo motors added to mechanical Gen 1 designs
Gen 3 – full servo driven electronic line shaft machine
Gen 4 will be the generation of the adaptive machine.
The adaptive machine terminology was developed to define a category, as well as to define the purpose, functionality and especially the application benefits of such technologies to make production processes more flexible and productive in terms of commercial objectives.
The adaptive machine and machine learning
The adaptive machine category should not be confused with adaptive manufacturing or adaptive machine learning. Adaptive machines can be quite effective in an adaptive manufacturing environment and can benefit from adaptive machine learning applications. But they are neither interchangeable terms nor require one another to fulfill their basic definitions.
Adaptive machines in the commercial marketplace
Adaptive machines are increasingly entering the industrial workplace. Applications include ‘bottling on demand,’ in which soft drinks are individually blended at the filling valve and fitted with customized closures and labels and product codes.
Another is a labeling machine that can handle different size and shape bottles and labels without stopping and performing a changeover.
Another example is a bottle unscrambler that uses a combination of delta robots and the synchronized motion of two shuttles to act as infinitely adjustable pucks, to handle different container shapes and sizes, also without changeover.
A cartoning machine uses a track system in place of a variable pitch bucket conveyor for collating and loading different primary packs into cartons.
References
Management cybernetics
Manufacturing
Product management
Mechanical engineering | Adaptive machine | [
"Physics",
"Engineering"
] | 991 | [
"Applied and interdisciplinary physics",
"Manufacturing",
"Mechanical engineering"
] |
64,758,487 | https://en.wikipedia.org/wiki/Concatenation%20%28architecture%29 | The concatenation (enchainement) is an architectural composition that unites chaining parts together—as with separate elements in long façades, with the fronts being brought forward or recessed.
Overview
The concatenation usually articulates the wall by superimposing elements of the architectural order, such as pilasters or engaged columns, inside which a round arch or a series of arches open. Two hierarchical orders are usually superimposed: the minor order supports the arch, which, in turn, is framed under the entablature of the major order. The concatenation is different from the serliana that usually employs a single order on which both the arches and the architrave rest.
History
As an element of architectural language, the concatenation was common in the Roman architecture both in an isolated form (triumphal arches) and in series. It was also widely used in multi-level buildings, such as Colosseum. As a compositional element, it saw new interest in the first half of the 15th century, becoming a fundamental syntagm of the classical architecture. In the Renaissance architecture, the concatenation was widely used in all types of buildings, internal courtyards, and cloisters. William Kent and other Palladians favoured concatenated façades for their articulation.
Gallery
References
Architectural elements | Concatenation (architecture) | [
"Technology",
"Engineering"
] | 274 | [
"Building engineering",
"Architectural elements",
"Components",
"Architecture"
] |
64,760,108 | https://en.wikipedia.org/wiki/Track%20technology | Track technology is an industrial material handling system which uses linear motors to move material along a track. It has been variously termed a smart conveyance system, intelligent track system, industrial transport system, independent cart technology, smart carriage technology, linear or extended or flexible transport system, or simply a conveyor or conveyance platform. They are also referred to simply as linear motors or long stator linear motors, reflecting the underlying technology of the track (stator) and shuttles.
List of commercially available track systems
The following is a list of commercially available track systems by product name:
ACOPOStrak from B&R Industrial Automation
ActiveMover from Bosch Rexroth
iTRAK from Rockwell Automation
LCM100 and LCM100-X from Yamaha
Linear Motion System
Linear Transfer System
MagneMover LITE from Rockwell Automation
Multi Carrier System
Quickstick and Quickstick HT from Rockwell Automation
SuperTrak Conveyance from ATS Automation Tooling Systems
SuperTrak from B&R
XTS from Beckhoff
Technology adoption and maturity
ATS Automation was the first to utilize linear motor based conveyance with its SuperTrak Conveyance technology. The first commercial system was shipped in 2002.
According to Packaging World magazine in a January 2018 article, adoption of the technology continues to grow with a third generation of the technology reaching maturity. The article cites freedom from mechanical constraints, shortening changeovers and smaller machine footprints as reasons.
Track technology itself is not new. For example, Magnemotion (now part of Rockwell Automation) was founded in 1996, and they were not the first to develop the technology.
In a 2007 technical paper, MagneMotion explained the principles of operation, which they describe as a linear synchronous motor.
A 2014 case study article described the system's application in medical device assembly.
A 2013 case study described the use of ATS Automation's SuperTrak system in a flexible cartoning machine used in packaging lines.
This article, also from 2013, describes early packaging applications and principles of operation for track technology.
This article described a number of food processing applications, including the automation of labor-intensive tasks such as lasagna production. It also mentions a unique capability to prevent containers of liquids from sloshing, by matching the frequency of a shuttle's motion to the frequency that causes the sloshing.
This article summarized the activities of major players in track technology as of July 2018.
Areas of application
Track technology is – among other technologies like machine vision and robotics – one of the key enablers for the adaptive machine.
The concept of the adaptive machine also goes beyond track technology to achieve their high levels of flexibility. One complementary technology is the industrial robot, which by definition possesses the same programmable flexibility. Of particular interest is the ability of both robots and track systems to operate safely along with humans in a collaborative environment. This recent development allows for a combination of manual and automated assembly tasks, maintenance and materials replenishment without stopping production.
Machine vision can play a pivotal role when integrated into an adaptive machine. Vision can identify individual shuttles and their contents in order to guide them to the appropriate workstations. Vision has long been used to automate robot guidance, inspection, orientation and related tasks.
Given the adaptive machine's flexibility to respond to consumer demand generation, Internet of Things and e-commerce technologies are complementary, providing the connection between internal production resources and commercial systems in a manufacturer's digital business model.
References
Tracking
Technology systems
Technology by type | Track technology | [
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64,760,154 | https://en.wikipedia.org/wiki/Viral%20interference | Viral interference, also known as superinfection resistance, is the inhibition of viral reproduction caused by previous exposure of cells to another virus. The exact mechanism for viral interference is unknown. Factors that have been implicated are the generation of interferons by infected cells, and the occupation or down-modulation of cellular receptors.
Overview
Viral interference is considered the most common outcome of coinfection, or the simultaneous infection of a host by two or more distinct viruses. The primary form of viral interference is known as superinfection exclusion, in which the initial infection stimulates a resistance to subsequent infection by related viruses. Interference can occur as well in the form of superinfection suppression, in which persistently infected cells hold off infection by unrelated viruses. Viral interference has also been observed to occur in the use of vaccines containing live-attenuated viruses, in both directions — in some cases vaccines disrupting viruses unrelated to those they were targeting, and in others wild viruses rendering vaccines of this kind less effective.
Examples
Bacteriophage T4
A primary infection by bacteriophage (phage) T4 of its E. coli host ordinarily leads to genetic exclusion of a secondarily infecting phage, preventing the secondary phage from contributing its genetic information to progeny. This viral interference depends on the expression by the primary phage of the genes immunity (imm) and spackle (sp). The imm gp appears to enable the host exonuclease V to degrade the superinfecting phage DNA, and the sp gp appears to interfere with the DNA injection process of secondary phage. If the primary infecting phage is subjected to DNA damaging treatment prior to infection, this treatment tends to permit entry of the secondary phage's DNA, thus shifting reproduction from an asexual to a sexual mode and allowing rescue of the primary phage's genes.
Respiratory viruses
Interference has been observed to occur among endemic respiratory viruses. For example, human rhinovirus (HRV) infection has been shown to reduce the likelihood of codetection of other respiratory viruses, suggesting that it may confer a protective effect against other viruses such as influenza. The mechanism at play here has been suggested to be the expression of interferon-stimulated genes in the "target tissue" of HRV infection — the epithelium of the airway, where there has been observed to be an "unexpected high prevalence" of the virus, even among asymptomatic individuals. This process thus stimulates an antiviral state, shielding nearby cells from further infection. This potential interplay between viruses such as HRV and influenza may be one factor contributing to the timing and severity of their separate though overlapping "seasons".
Interference has been reported between respiratory viruses in non-human animals as well, such as between avian influenza viruses and Newcastle disease virus in chicken, turkeys, and ducks.
Live-attenuated vaccines
The first smallpox vaccine, developed by Edward Jenner, used cowpox to prevent smallpox infection. Indeed, the term "vaccinate" comes from the Latin phrase variolae vaccinae, Jenner's name for cowpox.
Live enterovirus vaccines have been found to disrupt the spread of various unrelated respiratory viruses, such as influenza, HRV, and respiratory syncytial virus (RSV), in addition to poliovirus (itself an enterovirus), a phenomenon attributed to viral interference. Similarly, during mass immunization campaigns against polio, vaccination seemed to confer some protection against unrelated enteroviruses as well. At the same time, enteroviruses were also found to interfere with the vaccines themselves, leading to instances of vaccine failure.
History
Viral interference was observed as early as the 16th century. However, it was not until the 20th century that it was described in detail, following experiments involving plants in 1929, animals in 1935, and bacteriophages in 1942.
2009 influenza pandemic
The emergence of a novel influenza A virus (pandemic H1N1/09) in early 2009 afforded the opportunity to study how pandemic influenza and seasonal respiratory viruses might interact, placing the concept of viral interference "on more solid footing." The virus quickly spread across both the Northern and Southern Hemispheres through the middle of the year. While this is an unusual time for influenza activity in the north, the first wave of the pandemic in the south occurred during the typical influenza period. The pandemic virus quickly became the dominant strain of influenza, largely displacing the seasonal ones in many countries; however, complete replacement was not observed. Ultimately, activity generally peaked at the expected time for influenza in the Southern Hemisphere.
Despite the rapid spread around the world through the middle of the year, the pandemic remained in a lull during the summer in the north following an explosive outbreak in the spring. As predicted, the virus returned in epidemic proportions in the fall, earlier than the typical flu season but at a time when respiratory illnesses are known to become more prevalent. However, in countries such as Sweden, Norway, and France, the epidemic was "delayed" relative to its timing in other countries, such as the United States and Italy. This difference was attributed by some observers to a rhinovirus epidemic that broke out upon the reopening of schools, effectively "delaying" the rise in H1N1 cases until October. Studies on this potential interaction between HRV and the pandemic influenza at times came to divergent conclusions, however. While this "delay" in countries like Sweden was real (i.e., temporally speaking, the epidemic was later than in other places), studies also showed that coinfections were relatively common and that there was active cocirculation of the two viruses.
A systematic analysis of studies from 26 countries found that the influenza epidemic delayed the onset of RSV activity by an average of 0.58 months to 2.5 months. The effect was more pronounced in the Northern Hemisphere as compared to the Southern Hemisphere, perhaps due to the timing of the influenza outbreak relative to the period of typical RSV activity in each region; the tropics, meanwhile, experienced minimal delay. This impact persisted into the second RSV season after the start of the pandemic, albeit to a lesser degree, and was no longer observed by the third season.
COVID-19 pandemic
During the COVID-19 pandemic, the circulation of many respiratory viruses changed dramatically. Amid the rapid global spread of the pandemic SARS-CoV-2 throughout 2020, these viruses, including influenza, fell to historically low levels. Influenza activity remained virtually nonexistent into 2021, when it began to be detected more frequently, but was still low during the 2021–2022 flu season. RSV activity was similarly depressed during the first year of the pandemic, before resurging in 2021. By contrast, cases of HRV and respiratory enteroviruses declined at the onset of the pandemic but soon returned to prepandemic levels, circulating relatively normally.
The above reductions have generally been attributed to the imposition of nonpharmaceutical interventions, such as social distancing, mask use, and school closures. However, viral interference has also been suggested as the driving force, or least another driving force, behind this major decline in viral activity, based in part on the experience of the 2009 pandemic. For example, in the winter of 2021–2022, during the surge of the highly transmissible Omicron variant of SARS-CoV-2 in the United States, influenza activity plummeted as the pandemic wave grew, peaking again in the spring once Omicron had subsided. A similar phenomenon was observed in Hong Kong in March 2022, when other respiratory viruses "disappeared" during the surge before returning in April. With respect to HRV and respiratory enteroviruses, whose behavior was evidently less affected during the pandemic, an apparent interplay between these and SARS-CoV-2, possibly mediated by viral interference, was identified in some places, such as California and South Korea. Although these viruses continued to circulate at near prepandemic levels, they were found to peak when SARS-CoV-2 activity was low and to decline as SARS-CoV-2 activity increased.
References
Epidemiology
Virology | Viral interference | [
"Environmental_science"
] | 1,740 | [
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69,124,573 | https://en.wikipedia.org/wiki/Optogenetic%20methods%20to%20record%20cellular%20activity | Optogenetics began with methods to alter neuronal activity with light, using e.g. channelrhodopsins. In a broader sense, optogenetic approaches also include the use of genetically encoded biosensors to monitor the activity of neurons or other cell types by measuring fluorescence or bioluminescence. Genetically encoded calcium indicators (GECIs) are used frequently to monitor neuronal activity, but other cellular parameters such as membrane voltage or second messenger activity can also be recorded optically. The use of optogenetic sensors is not restricted to neuroscience, but plays increasingly important roles in immunology, cardiology and cancer research.
History
The first experiments to measure intracellular calcium levels via protein expression were based on aequorin, a bioluminescent protein from the jellyfish Aequorea. To produce light, however, this enzyme needs the 'fuel' compound coelenteracine, which has to be added to the preparation. This is not practical in intact animals, and in addition, the temporal resolution of bioluminescence imaging is relatively poor (seconds-minutes). The first genetically encoded fluorescent calcium indicator (GECI) to be used to image activity in an animal was cameleon, designed by Atsushi Miyawaki, Roger Tsien and coworkers in 1997. Cameleon was first used successfully in an animal by Rex Kerr, William Schafer and coworkers to record from neurons and muscle cells of the nematode C. elegans. Cameleon was subsequently used to record neural activity in flies and zebrafish. In mammals, the first GECI to be used in vivo was GCaMP, first developed by Junichi Nakai and coworkers in 2001. GCaMP has undergone numerous improvements, notably by a team of scientists at the Janelia Farm Research Campus (GENIE project, HHMI), and GCaMP6 in particular has become widely used in neuroscience. Very recently, G protein-coupled receptors have been harnessed to generate a series of highly specific indicators for various neurotransmitters.
Design principles
Genetically encoded sensors are fusion proteins, consisting of a ligand binding domain (sensor) and a fluorescent protein, attached by a short linker (flexible peptide). When the sensor domain binds the correct ligand, it changes conformation. This movement is transferred to the fluorescent protein and the resulting deformation leads to a change in fluorescence. The efficiency of this process depends critically on the length of the linker region, which has to be optimized in a labor-intensive process. The fluorescent protein is often circularly permuted, i.e. new C-terminal and N-terminal ends were created. Single-wavelength sensors are easy to use for qualitative measurements, but difficult to calibrate for quantitative measurements of ligand concentration.
A second class of sensors relies on Förster resonance energy transfer (FRET) between two fluorescent proteins (FP) of different color. The shorter wavelength FP (donor) is excited with blue light from a laser or LED. If the second FP (acceptor) is very close, the energy is transferred to the acceptor, resulting in yellow or red fluorescence. When the acceptor FP moves further away, the donor emits green fluorescence. The sensor domain is typically spliced between the two FPs, resulting in a hinge-type movement upon ligand binding that changes the distance between donor and acceptor. The imaging procedure is more complex for FRET sensors, but the fluorescence ratio can be calibrated to measure the absolute concentration of a ligand. Read-out via fluorescence lifetime imaging (FLIM) of donor fluorescence is also possible, as the FRET process speeds up the fluorescence decay.
Advantages of optogenetic sensors
can be targeted to specific classes of cells (e.g. astrocytes or pyramidal cells). This allows for optical read-out without spatial resolution, e.g. fiber photometry from deep brain areas.
can be targeted to sub-cellular compartments (e.g. synapses, organelles, nucleus) by fusing the indicator protein with specific anchoring domains, retention signals or intrabodies.
work in a variety of species (nematodes, insects, fish, mammals) and in cell culture systems (FLIPR assay)
can be delivered by viral vectors (e.g. rAAV)
can be used to record the activity of thousands of neurons at the same time
Drawbacks, limitations
will buffer the measured ion or protein, potentially interfering with cellular signaling
are subject to photobleaching, compromising long-term measurements
can be toxic when expressed at very high concentration
require highly sensitive cameras or laser scanning microscopes
some GPCR-based sensors are sensitive to polarization
most indicators are green fluorescent, making it difficult to measure several cellular parameters simultaneously (multiplexing).
Classes of genetically encoded indicators
Indicators have been designed to measure ion concentrations, membrane potential, neurotransmitters, and various intracellular signaling molecules. The following list provides only examples for each class; many more have been published.
Intracellular signaling
Genetically encoded calcium indicators (GECI): A large class of tools, based on natural calcium binding proteins (calmodulin, troponin). Different affinities, kinetics, and colors (green, red) available. Read-out via fluorescence intensity (single wavelength indicators), FRET or BRET. Have been targeted to various organelles. Current version: JGCaMP8
Genetically encoded chloride indicators: Clomeleon
Genetically encoded potassium indicators: GINKO2
Genetically encoded indicators for intracellular pH (GEPhI): CypHer
Genetically encoded voltage indicators (GEVI): ArcLight
Genetically encoded vesicle fusion sensors: Synapto-pHluorin, Synaptophysin-pHluorin
Genetically encoded cAMP sensors: EPAC
Genetically encoded ATP sensors: QUEEN-37C
Genetically encoded kinase activity sensors: CaMui, SmURFP
Genetically encoded Small G-protein sensors: FRas
Neurotransmitters and other extracellular signals
Genetically encoded glutamate sensors: GluSnFR
Genetically encoded GABA sensors: iGABASnFR
Genetically encoded dopamine sensors: dLight1, GRAB-DA
Genetically encoded serotonin sensors: GRAB5-HT, sDarken, iSeroSnFR
Genetically encoded norepinephrine sensors: GRABNE
Genetically encoded sensor for endocannabinoid activity: GRABeCB2.0
Genetically encoded sensor for orexin/hypocretin neuropeptides: OxLight1
Genetically encoded sensor for lactate: eLACCO1.1
Further reading
A recent review of GPCR-based genetically encoded fluorescent indicators for neuromodulators
External links
Fluorescent Biosensor Database, a fairly complete searchable list of published sensors and their basic properties, maintained by Jin Zhang's lab at UCSD.
Fluorescent Biosensors available on Addgene, a nonprofit plasmid repository.
References
Neuroscience
Biological techniques and tools
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69,125,439 | https://en.wikipedia.org/wiki/Matrix-M | Matrix-M is a vaccine adjuvant, a substance that is added to various vaccines to stimulate the immune response. It was patented in 2020 by Novavax and is composed of nanoparticles from saponins extracted from Quillaja saponaria (soapbark) trees, cholesterol, and phospholipids. It is an immune stimulating complex (ISCOM), which are nanospheres formed when saponin is mixed with two types of fats.
Adjuvants increase the body's immune response to a vaccine by creating higher levels of antibodies. They can either enhance, modulate, and/or prolong the body's immune response, reducing the number of vaccinations needed for immunization.
The Matrix-M adjuvant is used in a number of vaccine candidates, including the malaria vaccine R21/Matrix-M, influenza vaccines, and in the approved Novavax COVID-19 vaccine. In 2021, the R21/Matrix-M malaria vaccine candidate showed a 72% in sites with seasonal implementation and 67% in sites with age-based implementation in the modified per-protocol analysis. /> In influenza vaccine candidates, Matrix-M was shown to offer cross-protection against multiple strains of influenza.
Novavax is also testing a combined flu and COVID-19 vaccine candidate with Matrix-M.
References
Adjuvants
Saponins
Immunostimulants
Triterpene glycosides | Matrix-M | [
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69,125,570 | https://en.wikipedia.org/wiki/Harriet%20Florence%20Maling | Harriet Florence Maling (née Mylander, October 2, 1918 – March 1987) was an American pharmacologist. She graduated Phi Beta Kappa from Goucher College in 1940. She went to Harvard Medical School to continue her studies, earning a PhD in 1944.
Her focus of study involved the physiology of the heart, the effects of various drugs upon the heart and on the autonomic and sympathetic nervous systems, experimenting with artificially created myocardial infarction.
Her daughter Joan Maling is a linguist and past president of the Linguistic Society of America.
References
1918 births
1987 deaths
American pharmacologists
Goucher College alumni
Harvard Medical School faculty
Women pharmacologists
National Institutes of Health faculty
Harvard Medical School alumni
20th-century American chemists | Harriet Florence Maling | [
"Chemistry"
] | 154 | [
"Pharmacology",
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69,125,797 | https://en.wikipedia.org/wiki/Colossal%20Biosciences | Colossal Biosciences Inc. is an American biotechnology and genetic engineering company working to de-extinct the woolly mammoth, the Tasmanian tiger, the northern white rhinoceros, and the dodo. In 2023, it stated that it wants to have woolly mammoth hybrid calves by 2028, and wants to reintroduce them to the Arctic tundra habitat. Likewise, it launched the Tasmanian Thylacine Advisory Committee, a thylacine research project to release Tasmanian tiger joeys back to their original Tasmanian and broader Australian habitat after a period of observation in captivity.
The company develops genetic engineering and reproductive technology for conservation biology. It was founded in 2021 by George Church and Ben Lamm, and is based in Dallas, Texas.
History
Foundation
In a 2008 interview with The New York Times, George Church first expressed his interest in engineering a hybrid Asian elephant-mammoth by sequencing the woolly mammoth genome. In 2012, Church was part of a team that pioneered the CRISPR-Cas9 gene editing tool, through which the potential for altering genetic code to engineer the envisioned “mammophant" surfaced. Church presented a talk at the National Geographic Society in 2013, where he mapped out the idea of Colossal.
Church and his genetics team used CRISPR to copy mammoth genes into the genome of an Asian elephant in 2015. That same year, Church's lab integrated mammoth genes into the DNA of elephant skin cells; the lab zeroed in on 60 genes that experiments hypothesized as being important to the distinctive traits of mammoths, such as a high-domed skull, ability to hold oxygen at low temperatures, and fatty tissue. Church's lab reported in 2017 that it had successfully added 45 genes to the genome of an Asian elephant.
In 2019, Ben Lamm, a serial entrepreneur, contacted Church to meet at his lab in Boston. Lamm was intrigued by press reports of Church's de-extinction idea.
Launch
Colossal was officially launched on September 13, 2021. The launch included a $15 million seed round led by Thomas Tull, Tim Draper, Tony Robbins, Winklevoss Capital Management, Breyer Capital and Richard Garriott. In addition to the de-extinction of the woolly mammoth, Colossal, in partnership with Dr. Paul Ling of Baylor College of Medicine, hopes to synthesize the elephant endotheliotropic herpesvirus, a virus which infects and kills many young Asian elephants.
Colossal also announced that the company's mission was to preserve endangered animals through gene-editing technology and use those same animals to reshape Arctic ecosystems to combat climate change.
The company's genomic modeling software development could potentially bring forth advancements in disease treatment, multiplexed genetic engineering, synthetic biology, and biotechnology. Colossal recruited mammoth and modern elephant experts Michael Hofreiter and Fritz Vollrath, as well as bioethicists R. Alta Charo and S. Matthew Liao for their consultation. Other scientific advisory board members include: Carolyn Bertozzi, Austin Gallagher, Kenneth Lacovara, Beth Shapiro, Helen Hobbs, David Haussler, Elazar Edelman, Joseph DeSimone, Erez Lieberman Aiden, Christopher E. Mason, and Doris Taylor.
In October 2021, Colossal announced its partnership with VGP; through this collaboration, Colossal will provide funding for VGP to sequence and assemble Asian, African bush, and African forest elephant genomes for preservation purposes. These genomes were made publicly accessible for research without use restrictions in July 2022 and May 2023, respectively.
In March 2022, Colossal raised $60 million in a Series A funding round led by Thomas Tull with participation from Animoca Brands, Paris Hilton, Charles Hoskinson, bringing the total funding to $75 million.
Colossal spun out its software platform, Form Bio, in September 2022 with $30 million in funding. Lamm has stated that Colossal is run like a software company, and monetization will stem from technologies developed by the company. Form Bio has developed an AI-based software platform designed to help scientists manage large and complicated datasets.
In January 2023, Colossal completed a Series B funding round, raising an additional $150 million and putting the company's valuation at over $1 billion. The same month, Colossal launched its Conservation Advisory Board, which includes Forrest Galante, Iain Douglas-Hamilton, Mead Treadwell, and Aurelia Skipwith as its members.
In October 2024, Colossal announced $50 million in funding for its launch of the Colossal Foundation.
Science and development
Because the woolly mammoth and Asian elephant share 99.6% of the same DNA, Colossal aims to develop a proxy species by swapping enough key mammoth genes into the Asian elephant genome. Key mammoth genealogical traits include: a 10-centimeter layer of insulating fat, five different types of shaggy hair, and smaller ears to help the hybrid tolerate cold weather.
Colossal's lab will pair CRISPR/Cas9 with other DNA-editing enzymes, such as integrases, recombinases, and deaminases, to splice woolly mammoth genes into the Asian elephant. The company plans on sequencing both elephant and mammoth samples in order to identify key genes in both species to promote population diversification. By doing so, Colossal hopes to prevent any rogue mutations within the hybrid herd. Colossal set a goal for the company to grow a woolly mammoth calf by 2028.
The company plans to use African and Asian elephants as potential surrogates and largely plans to develop artificial elephant wombs lined with uterine tissue as a parallel path to gestation. Colossal scientists plan on creating these embryos by taking skin cells from Asian elephants and reprogramming them into induced pluripotent stem cells which carry mammoth DNA. Lamm stated that Colossal will use both induced pluripotent stem cells (iPSC) as well as somatic cell nuclear transfer in the process.
In July 2022, VGP and Colossal announced that they successfully sequenced the entire Asian elephant genome; this is the first time that mammalian genetic code has been fully sequenced to this degree since the Human Genome Project was completed in the early 2000s.
In August 2022, Colossal announced that they would launch a thylacine research project, in hopes of "de-extincting" the Tasmanian tiger. Colossal plans to reintroduce the thylacine proxy to selected areas in Tasmania and broader Australia and claims that, by doing so, this will re-balance ecosystems that have suffered biodiversity loss and degradation since the species disappeared. A successful thylacine proxy birth could also introduce new marsupial-assisted reproductive technology which can aid in other marsupial conservation efforts. Colossal is partnering with the University of Melbourne, and the project is led by Andrew Pask. The Tasmanian Thylacine Advisory Committee was launched in December 2023.
In January 2023, Colossal announced the formation of its Avian Genomics Group, which will be dedicated to reconstructing the DNA of the dodo bird, which went extinct in the 1600s. Led by Beth Shapiro, who serves as Chief Science Officer to Colossal, this research group aims to create a hybrid composed of specific traits most commonly associated with the dodo and plans to reintroduce these hybrids into their respective environments. Colossal will be working with primordial germ cells to pair dodo DNA with the genome of the Nicobar pigeon, the extinct dodo's closest living relative.
Breaking, a plastic degradation and synthetic biology startup, was launched in April 2024. Gestated at Colossal, Breaking discovered X-32, a microbe that is capable of breaking down various plastics in as little as 22 months while leaving behind carbon dioxide, water and biomass.
It was reported in 2024 that Colossal successfully produced the first-ever elephant and dunnart iPSCs.
In October 2024, the company announced that it had rebuilt a 99.9% accurate genome of the thylacine, using a “pickled” 110-year-old fossilized Tasmanian tiger skull. This marks “the most complete ancient genome of any species known to date” and provides a full DNA blueprint to potentially bring back the Tasmanian tiger. Three months later in January 2025, the company sequenced the complete genome of the Tasmanian tiger, bringing the species closer to de-exinction"
Future de-extinction projects
Outside of their first four projects, Colossal Biosciences has stated that they have a "long list" of species that they want to revive and reintroduce to appropriate ecosystems. Such species include Castoroides, Arctodus, and Steller's sea cow. Ben Lamm has stated that he and his company want to revive Steller's sea in cow once they have developed an artificial animal womb, as there are no adequate living relatives of the extinct sea cow to act a surrogate species. Colossal has also done genetic research for species such as the Irish elk, great auk, bluebuck, ground sloth, moas, and woolly rhinoceros with the intent to potentially revive them in the future.
Conservation
In October 2022, Colossal announced that it was developing a vaccine for elephant endotheliotropic herpesvirus (EEHV), in partnership with the Baylor College of Medicine.
In May 2023, Colossal partnered with the Vertebrate Genomes Project to successfully generate the first high-quality reference genome of an African elephant. This sequencing work is part of a long-term conservation effort for the endangered elephant species.
In September 2023, Colossal partnered with BioRescue to help save the northern white rhino from extinction by using reproduction technology and stem cell technology, as the subspecies is functionally extinct with only two known infertile female members left.
Colossal and Zoos Victoria began a conservation project in October 2023 to preserve the Victorian Grassland Earless Dragon as well as sequence its genome.
In November 2023, Colossal announced a research partnership with Save the Elephants to track African elephants in the Samburu National Reserve. Save the Elephants has already tracked over 900 elephants in the area, using drones equipped with high-resolution infrared cameras. Colossal plans to use pose estimation to develop algorithms for labeling elephants and automatically identifying individual & collective social behavior.
Colossal also began a partnership with the Mauritian Wildlife Foundation in November 2023. Under this collaboration, the organizations will work to restore “critical ecosystems through invasive species removal, revegetation, and community awareness efforts.” Additionally, Colossal will also focus on the rewilding of the dodo bird as well as the genetic rescue of the pink pigeon.
In March 2024, Colossal and Re:wild partnered together to establish a “10-year conservation strategy” to accelerate efforts to “save species on the brink of extinction, search for lost species, and restore key habitats for species recovery and rewilding.”
In May 2024, Colossal and the University of Melbourne announced the successful engineering of cane toad toxin resistance in marsupial cells, as part of conservation efforts for the northern quoll. Colossal’s refined engineering resistance strategy can create over 6,000-fold increased resistance with just one edit to the genome.
The first-ever mRNA vaccine for elephant endotheliotropic herpesvirus (EEHV), developed by Colossal, the Houston Zoo, and the Baylor College of Medicine, was administered to an elephant in July 2024.
In October 2024, Colossal announced its launch of the Colossal Foundation, a non-profit initiative that utilizes Colossal-developed science and technology methods for partner-led conservative efforts. Included in its conservation agenda is the Colossal Biovault, "the world's largest distributed biobanking initiative." The Colossal Biovault collects tissue samples of endangered species in hopes to allow cell lines to become accessible and stored in domestic partner facilities. Its first projects include: Sumatran rhinoceros, red wolf, northern quoll, pink pigeon, tooth-billed pigeon, Victorian grassland earless dragon, vaquita, and ivory-billed woodpecker.
In December 2024, Colossal and University of Melbourne began research into engineering an immunity to chytridiomycosis, a lethal fungal-based disease in amphibians that is responsible for many extinctions and declines in amphibians, including the golden toad and Rabbs' fringe-limbed tree frog.
Reception
In 2022, Colossal was listed as one of the World Economic Forum's Technology Pioneers and was named Genomics Innovation of the Year by the BioTech Breakthrough Awards.
Colossal was included as part of Time's 100 Most Influential Companies 2023 list.
Colossal was voted one of the best places to work in Dallas, Texas, U.S. by Builtin in 2025.
References
Biotechnology companies established in 2021
Genome projects
Conservation biology
Biotechnology companies
Companies based in Dallas
Privately held companies based in Texas
2021 establishments in Texas | Colossal Biosciences | [
"Engineering",
"Biology"
] | 2,629 | [
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"Genome projects",
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69,126,363 | https://en.wikipedia.org/wiki/Phase-out%20of%20polystyrene%20foam | In the late 20th and early 21st century, there has been a global movement towards the phase-out of polystyrene foam as a single use plastic (SUP). Early bans of polystyrene foam intended to eliminate ozone-depleting chlorofluorocarbons (CFCs), formerly a major component.
Expanded polystyrene, often termed Styrofoam, is a contributor of microplastics from both land and maritime activities. Polystyrene is not biodegradeable but is susceptible to photo-oxidation, and degrades slowly in the ocean as microplastic marine debris. Animals do not recognize polystyrene foam as an artificial material, may mistake it for food, and show toxic effects after substantial exposure.
Full or partial bans of expanded and polystyrene foam commonly target disposable food packaging. Such bans have been enacted through national legislation globally, and also at sub-national or local levels in many countries.
Legislation around the world
National legislation
China banned expanded polystyrene takeout/takeaway containers and tableware in 1999, but later revoked the policy in 2013 amidst industry lobbying. Haiti banned foam food containers in 2012 to reduce waste in canals and roadside drains. In 2019, the European Parliament voted 560 to 35 to ban all food and beverage containers made from expanded polystyrene throughout the European Union member states. Canada amended its 'Canadian Environmental Protection Act, 1999' in 2022 to prohibit foodservice ware made of expanded or extruded polystyrene, and also polyvinyl chloride, black colored plastics, or oxo-degraded plastics.
Summary
Subnational legislation
In Australia, over 97% of the population live in an area that bans expanded polystyrene. Between 2021-2023, the Australian Capital Territory, New South Wales, Queensland, South Australia, Victoria, and Western Australia enacted bans.
Nigeria's states of Lagos and Abia introduced bans in January 2024, with an initial transition period of three weeks. The state of Oyo introduced a ban in March 2024.
Municipal bans in the Philippines are in effect in Bailen, Boracay, Caloocan, Cordova, El Nido, Las Piñas, Makati, Mandaluyong City, Muntinlupa, Quezon City, and Tacloban.
In the United Arab Emirates, the municipal government of Dubai announced a ban affecting polystyrene in 2025, and all single-use plastic food containers in 2026.
Phaseout in the United States
As of June 2024, 11 U.S. states and two territories have passed statewide legislation to explicitly ban polystyrene foam:
In 2019, Maryland was the first state to enact a ban, which went into effect on October 1, 2020. Bans were also passed that year in Maine and Vermont, with both states' laws taking effect on July 1, 2021.
In 2020, New York passed a ban that took effect on January 1, 2022, while New Jersey passed a ban that took effect on May 4, 2022.
In 2021, Colorado passed a ban that took effect on January 1, 2024. Virginia passed a ban on polystyrene food containers coming into force in July 2025 (for larger businesses) and July 2026 (for businesses with less than 20 locations). Washington also passed a polystyrene ban, effective starting in June 2023, with food serviceware prohibited starting June 1, 2024.
In 2023, Delaware, Oregon and Rhode Island all signed bans into law, with provisions set to take effect in each state in 2025.
Washington, D.C. banned polystyrene foam takeout containers on January 1, 2016. The ban was expanded on January 1, 2021, to include the retail sale of polystyrene foam.
American Samoa banned the import, sale, and distribution of polystyrene foam containers on February 6, 2024, taking effect 60 days later.
In Hawaii, a de facto ban is in effect after every county enacted polystyrene bans except state-administered Kalawao County. Bans in Hawaii County took effect July 2019, followed by Kauai County, Maui County, and Honolulu County in 2022. Maui separately banned polystyrene foam coolers, and the sale or rental of disposable bodyboards in 2022.
In California, the legislature passed SB54 in June 2022 as the Plastic Pollution Prevention and Packaging Producer Responsibility Act. The law codifies extended producer responsibility (EPR) requirements for plastics, including a requirement that polystyrene be banned if recycling rates do not reach 25% by 2025. Recycling rates averaged 6% at passage, leading some to call the law a 'de facto ban', anticipating an inability to comply within three years.
Local legislation
Local bans have been enacted elsewhere, including in many large and small cities within the US:
Alaska — In Alaska, the towns of Bethel, Cordova, and Seward have enacted bans.
California — At least 128 cities in California have an existing polystyrene ban in some form. As of 2023, 12 counties — namely Alameda, Contra Costa, Los Angeles, Marin, Mendocino, Monterey, San Francisco, San Luis Obispo, San Mateo, Santa Clara, Santa Cruz, and Sonoma have bans affecting the general public. Additionally, 27 municipalities in other counties, namely Arcata, Camarillo, Carlsbad, Carpinteria, Dana Point, Davis, Del Mar, Encinitas, Goleta, Imperial Beach, Laguna Beach, Newport Beach, Oceanside, Ojai, Oxnard, Palm Springs, Port Hueneme, San Clemente, San Diego, Santa Barbara, Solana Beach, South Lake Tahoe, Thousand Oaks, Truckee, Ventura, Vista, and Yountville have bans. Together these laws cover over 20.6 million people, or about 53% of the state's population. The city of Berkeley passed the nation's first polystyrene foodware ban in 1988, while also requiring all disposable foodware to be degradable or recyclable.
Connecticut — Hamden, Groton, Norwalk, Stamford, and Westport have all enacted bans. Hamden enacted the state's first ban in 1989, and continues to retain its original ordinance.
Georgia — South Fulton banned single-use plastics in 2019. Atlanta banned polystyrene at city-owned buildings, including Hartsfield–Jackson Atlanta International Airport.
Illinois — Oak Park and River Forest have enacted bans. In 2023, the state legislature passed a ban affecting state agencies and universities.
Massachusetts — At least 66 municipalities have bans on polystyrene, including Abington, Acton, Amherst, Andover, Arlington, Athol, Attleboro, Brookline, Buckland, Cambridge, Chatham, Chelmsford, Concord, Dennis, Eastham, Easthampton, Essex, Fairhaven, Falmouth, Georgetown, Gloucester, Grafton, Great Barrington, Greenfield, Hadley, Hamilton, Hanson, Ipswich, Lee, Lenox, Lexington, Lincoln, Manchester-by-the-Sea, Marblehead, Maynard, Medford, Melrose, Nantucket, Newton, Northborough, Northampton, Orleans, Pittsfield, Provincetown, Raynham, Reading, Revere, Rockport, Salem, Saugus, Shrewsbury, Somerville, South Hadley, Stockbridge, Sudbury, Swampscott, Upton, Wayland, Wellfleet, Westborough, Westfield, Westford, Whitman, Williamstown, Winthrop, and Yarmouth.
Minnesota — Minneapolis enacted a ban in 1989, and amended the largely unenforced ban in 2015. In 2017, the city of St. Louis Park effectively banned single-use polystyrene after mandating compostable, reusable, or locally recyclable packaging. Saint Paul enacted a similar provision in 2022.
New Hampshire — Portsmouth enacted the first ban in New Hampshire in 2020.
New Mexico — Santa Fe County passed a ban on serving food, or packing eggs, baked goods, or produce in polystyrene containers, affecting unincorporated parts of the county.
Pennsylvania — The Boroughs of Ambler, Narberth, Newtown, Phoenixville, Swarthmore, and Townships of Montgomery, Newtown, Solebury, Tredyffrin, Upper Merion, Upper Moreland, and Uwchlan enacted bans.
South Carolina — The city of Charleston adopted an ordinance in 2018, with the surrounding Charleston County adopting a similar ordinance the year after.
Proposed legislation
As of August 2023, proposed legislation banning polystyrene has passed at least one legislative chamber in two states and one territory. In Connecticut, SB 118 passed the state Senate in April 2022, but died when the session ended. In Illinois, the state House passed HB2376 on March 21, 2023.
The territory of the Northern Mariana Islands passed HB21-89 in its House of Representatives in 2020.
In September 2021, Florida introduced a proposed phaseout of polystyrene foam food packaging. Commissioner of Agriculture Nikki Fried, whose Florida Department of Agriculture and Consumer Services oversees food safety in Florida, proposed a rule to phase out polystyrene in 40,000 grocery stores, food markets, convenience stores, and gas stations that the agency regulates in Florida. The Florida Legislature will consider the proposed rule in 2022.
See also
Plastic bag ban
Polystyrene
Styrofoam
Notes
References
Environmentalism
Foams
Technological phase-outs | Phase-out of polystyrene foam | [
"Chemistry"
] | 1,976 | [
"Foams"
] |
69,127,114 | https://en.wikipedia.org/wiki/Volkswagen%20Group%20W-12%20engine | Volkswagen Group have produced a number of W12 internal combustion piston engines for their Volkswagen, Audi, and Bentley marques, since 2001.
Overview
The only mass-production W12 engine is the Volkswagen 6.0 WR12 48v, a four-bank design which was released in 2001. This engine has been used in several models from the brands Audi, Bentley, and Volkswagen, and in 2003 a turbocharged version was released.
The engine is constructed by mating two narrow-angle 15° VR6 engines at an inclined angle of 72°. The narrow angle of each set of cylinders allows just two overhead camshafts to drive each pair of banks, so the W12 engine has the same number of camshafts as a V12 engine. The W12 engine has a very compact design for a 12-cylinder engine, with the overall size of the engine being smaller than Volkswagen's contemporary V8 engine.
The first application of the Volkswagen W12 was the 2001 Volkswagen W12, a mid-engined concept car which set the 24‑hour world endurance record in 2001 with a distance of and an average speed of . The first production car to use the W12 engine was the 2001 Audi A8 (D2). Other cars to use the W12 engine are the 2005-present Bentley Continental Flying Spur, 2015–present, 2004-2011 Volkswagen Phaeton W12 and the 2005-2010 Volkswagen Touareg W12. The engine was also used in the 2006 Spyker C12 La Turbie and 2008 Spyker C12 Zagato low-volume sports cars.
Variants
6.0 WR12 48v
This W12 badged W12 engine is twelve cylinder W engine of two rows of (staggered) 6 cylinders, formed by joining two imaginary 15° VR6 engine cylinder blocks, placed on a single crankshaft, with each cylinder 'double-bank' now at a 72° angle. This specific configuration is more appropriately described as a WR12 engine.
This Volkswagen Group engine is also used with slight modification, and with the addition of two turbochargers in the, Bentley Continental Flying Spur. It has also been used in a form aboard the Volkswagen W12 prototype sports car to establish a 24-hour record of in 2002 at the Nardò Ring in Italy.
identification parts code prefix: 07C
engine displacement & engine configuration 72° W12 engine; bore x stroke: , stroke ratio: 0.93:1 – undersquare/long-stroke, 499.9 cc per cylinder, compression ratio: 10.7:1: 72° W12 engine; bore x stroke: , stroke ratio: 0.93:1 – undersquare/long-stroke, 496 cc per cylinder, compression ratio: 10.7:1
cylinder block & crankcase homogeneous monoblock low-pressure chill die cast hypereutectic 'Alusil' aluminium-silicon alloy (AlSi17Cu4Mg); torsionally stiff aluminium alloy crankcase with high-resistance cylinder liners, simplex roller chain driven oil pump; die-forged steel 21.2 kg crankshaft, seven main bearings, crankpins offset to achieve a constant firing order as on a V6 engine
cylinder heads & valvetrain cast aluminium alloy; four valves per cylinder, 48 valves total, low-friction roller finger cam followers with automatic hydraulic valve clearance compensation, double overhead camshaft driven from the flywheel side via a two-stage chain drive utilising three 3/8" simplex roller chains, continuous vane-adjustable variable valve timing for intake and exhaust camshafts with up to 52 degrees timing range for the flow-optimised inlet ports, 22 degrees on the exhaust camshafts
aspiration two air filters, two hot-film air mass meters, two throttle bodies each with electronically controlled Bosch 'E-Gas' throttle valves, four-part two-channel cast magnesium alloy intake manifold; Bentley versions also use twin-turbos – one turbocharger per VR cylinder bank
fuel system, ignition system, engine management two linked common rail fuel distributor rails, multi-point electronic sequential indirect fuel injection with twelve intake manifold-sited fuel injectors; centrally positioned NGK longlife spark plugs, mapped direct ignition with 12 individual direct-acting single spark coils; Bosch Motronic ME 7.1.1 electronic engine control unit (ECU), cylinder-selective knock control via four knock sensors, permanent lambda control, water-cooled alternator
exhaust system two vacuum-controlled secondary air injection pumps for direct injection into exhaust ports to assist cold start operation, four exhaust manifolds with four integrated ceramic catalytic converters, eight heated oxygen sensors monitoring pre- and post catalyst exhaust gases
dimensions length: , height: , width: then
DIN-rated motive power & torque outputs – Audi / Volkswagen, ID codes
; — Audi A8: AZC (01/01-09/02), VW Phaeton: BAN (04/02-05/05)
at 6,200 rpm, at 4,000 rpm, at 2,300–5,300 rpm — Audi A8: BHT, BSB, BTE (12/03-07/10)
at 6,000 rpm; at 2,750–5,000 rpm — Phaeton: BRN, BTT (05/05-03/16)
at 6,000 rpm; at 3,300 rpm — Touareg: BJN, CFRA (08/04-05/10)
DIN-rated motive power & torque outputs – Bentley twin turbo
at 6,100 rpm; at 1,600–6,100 rpm — standard models: BWR, BEB, MTBHT
at 6,000 rpm; at 1,700–5,600 rpm — "Speed" models: CKHC, BWRA
at 5,900 rpm; at 2,050–4,500 rpm — "Supersports" model
applications (5998cc) Audi A8 (AZC: 03/01-09/02, BHT: 02/04-, BSB: 10/04-, BTE: 02/05-), Volkswagen Phaeton (BAN: 05/02-05/05, BRN: 05/05-10/08, BTT: 05/05-10/08), Volkswagen Touareg sport (BJN: 08/04-, CFRA: 02/08-), Bentley Continental GT, Bentley Continental Flying Spur:
applications(5952cc)
Bentley Continental GT, Bentley Continental Flying Spur, Bentley Bentayga
6.0 WR12 48v TFSI
This engine produces of power and of torque. It would mostly share the same technical specifications with its turbocharged 6.0-liter predecessor, other than the fact that it was modified to meet new WLTP emission standards. This new engine was promised to be made available on the fourth generation A8, following S8 and 60 TFSI/TDI models. However, as of August 2020, only examples of the W12 variant were press cars. It is rumoured that the W12 variant is only available as special orders in selected European dealerships.
6.3 WR12 48v FSI (CEJA)
This engine produces of power and of torque. This new engine was made available on the 3rd generation A8. It had more compact dimensions than a comparable V8 engine FSI direct injection with twin high-pressure fuel pumps, twin fuel rails, and six-port high-pressure injectors.
applications
A8 L W12 6.3 FSI quattro (CEJA)
Applications
Volkswagen W12
Audi A8
Bentley Continental GT
Bentley Flying Spur
Bentley Bentayga
Volkswagen Touareg W12
Spyker C12 La Turbie
Spyker C12 Zagato
Volkswagen Phaeton
References
references
reference
W engines
Volkswagen Group
Audi engines
Bentley engines
Volkswagen Group engines
Gasoline engines by model
Engines by model
Piston engines
Internal combustion engine | Volkswagen Group W-12 engine | [
"Technology",
"Engineering"
] | 1,633 | [
"Internal combustion engine",
"Engines",
"Engines by model",
"Piston engines",
"Combustion engineering"
] |
69,127,586 | https://en.wikipedia.org/wiki/Chord%20diagram%20%28mathematics%29 | In mathematics, a chord diagram consists of a cyclic order on a set of objects, together with a one-to-one pairing (perfect matching) of those objects. Chord diagrams are conventionally visualized by arranging the objects in their order around a circle, and drawing the pairs of the matching as chords of the circle.
The number of different chord diagrams that may be given for a set of cyclically ordered objects is the double factorial . There is a Catalan number of chord diagrams on a given ordered set in which no two chords cross each other. The crossing pattern of chords in a chord diagram may be described by a circle graph, the intersection graph of the chords: it has a vertex for each chord and an edge for each two chords that cross.
In knot theory, a chord diagram can be used to describe the sequence of crossings along the planar projection of a knot, with each point at which a crossing occurs paired with the point that crosses it. To fully describe the knot, the diagram should be annotated with an extra bit of information for each pair, indicating which point crosses over and which crosses under at that crossing. With this extra information, the chord diagram of a knot is called a Gauss diagram. In the Gauss diagram of a knot, every chord crosses an even number of other chords, or equivalently each pair in the diagram connects a point in an even position of the cyclic order with a point in an odd position, and sometimes this is used as a defining condition of Gauss diagrams.
In algebraic geometry, chord diagrams can be used to represent the singularities of algebraic plane curves.
See also
Arrangement of lines
Kontsevich invariant
References
Knot theory
Matching (graph theory) | Chord diagram (mathematics) | [
"Mathematics"
] | 345 | [
"Matching (graph theory)",
"Mathematical relations",
"Graph theory"
] |
69,127,974 | https://en.wikipedia.org/wiki/Volkswagen-Audi%20V8%20engine | The Volkswagen-Audi V8 engine family is a series of mechanically similar, gasoline-powered and diesel-powered, V-8, internal combustion piston engines, developed and produced by the Volkswagen Group, in partnership with Audi, since 1988. They have been used in various Volkswagen Group models, and by numerous Volkswagen-owned companies. The first spark-ignition gasoline V-8 engine configuration was used in the 1988 Audi V8 model; and the first compression-ignition diesel V8 engine configuration was used in the 1999 Audi A8 3.3 TDI Quattro. The V8 gasoline and diesel engines have been used in most Audi, Volkswagen, Porsche, Bentley, and Lamborghini models ever since. The larger-displacement diesel V8 engine configuration has also been used in various Scania commercial vehicles; such as in trucks, buses, and marine (boat) applications.
Discontinued production engines
Gasoline
All Volkswagen Group V8 gasoline engines are constructed from a lightweight, cast aluminum alloy cylinder block (crankcase) and cylinder heads. They all use multi-valve technology, with the valves being operated by two overhead camshafts per cylinder bank (sometimes referred to as 'quad cam'). All functions of engine control are carried out by varying types of Robert Bosch GmbH Motronic electronic engine control units. They are all longitudinally front-mounted, and the V8 engines listed below were for a long time only used in cars bearing the Audi marque, but latterly being installed in Volkswagen Passenger Cars flagship Volkswagen Phaeton.
3.6 V8 32v 184kW
identification parts code prefix: 077, ID code: PT
engine displacement & engine configuration 90° V8; bore x stroke: , stroke ratio: 0.94:1 – undersquare/long-stroke, 445.2 cc per cylinder; compression ratio: 10.6:1
cylinder block & crankcase cast aluminium alloy; five main bearings, die-forged steel crankshaft
cylinder heads & valvetrain cast aluminium alloy; four valves per cylinder, 32 valves total, timing belt and simplex chain-driven (hybrid system) double overhead camshafts
fuel system, ignition system, engine management common rail multi-point electronic sequential indirect fuel injection with eight intake manifold-sited fuel injectors; twin Hitachi ignition coils (one per cylinder bank) with Bosch longlife spark plugs, Bosch Motronic electronic engine control unit (ECU); 95 RON/ROZ(91 AKI) EuroPremium (regular) unleaded recommended for optimum performance and fuel economy
DIN-rated motive power & torque output at 5,800 rpm; at 4,000 rpm
application Audi V8 (10/88-11/93)
3.7 V8 32v 169kW
identification parts code prefix: 077, ID codes: AEW, AKJ
engine displacement & engine configuration 90° V8; bore x stroke: , stroke ratio: 1.03:1 – oversquare/short-stroke, 462.1 cc per cylinder; compression ratio: 10.8:1
cylinder block & crankcase cast aluminium alloy; five main bearings, die-forged steel crankshaft
cylinder heads & valvetrain cast aluminium alloy; four valves per cylinder, 32 valves total, timing belt and simplex chain-driven (hybrid system) double overhead camshafts
fuel system, ignition system, engine management common rail multi-point electronic sequential indirect fuel injection with eight intake manifold-sited fuel injectors; twin LAZ pre-power output stage control units (one per cylinder bank) and eight single spark ignition coils with Bosch longlife spark plugs, Bosch Motronic electronic engine control unit (ECU); 95 RON/ROZ(91 AKI) EuroPremium (regular) unleaded recommended for optimum performance and fuel economy
DIN-rated motive power & torque output at 5,500 rpm; at 2,700 rpm
application Audi D2 A8 (AEW: 07/95-12/98, AKJ: 06/97-12/98)
3.7 V8 40v 191-206kW
identification parts code prefix: 077, codes d'identification :AQG, AKC, BFL
engine displacement & engine configuration 90° V8; bore x stroke: , stroke ratio: 1.03:1 – oversquare/short-stroke, 462.1 cc per cylinder; compression ratio: 11.0:1 (BFL: 11.3:1)
cylinder block & crankcase cast aluminium alloy; five main bearings, die-forged steel crankshaft
cylinder heads & valvetrain cast aluminium alloy; five valves per cylinder, 40 valves total, low friction roller rocker fingers, timing belt and simplex chain-driven (hybrid system) hollow double overhead camshafts, variable inlet camshaft timing
aspiration 3-stage variable composite intake manifold
fuel system, ignition system, engine management common rail multi-point electronic sequential indirect fuel injection with eight intake manifold-sited fuel injectors; eight single spark ignition coils with Bosch longlife spark plugs, Bosch Motronic electronic engine control unit (ECU); 95 RON/ROZ(91 AKI) EuroPremium (regular) unleaded recommended for optimum performance and fuel economy
DIN-rated motive power & torque outputs, ID codes
at 6,000 rpm; at 3,250 rpm — AQG, AKC
at 6,000 rpm; at 3,750 rpm — BFL
applications Audi D2 A8 (AQG: 10/98-02/01, AKC: 05/00-09/02), Audi D3 A8 (BFL: 11/02-05/06)
Awards
was voted 'best technical innovation', and awarded the "Golden Pegasus" by "Za ruljom" at the Moscow Motor Show
4.6 V8 32v 206-250kW
identification parts code prefix: 0215
engine displacement & engine configuration 90° V8; bore x stroke: , stroke ratio: 0.91:1 – undersquare/long-stroke, 521.5 cc per cylinder; compression ratio: 10.3:1 (ABH: 10.8:1)
cylinder block & crankcase cast aluminium alloy; five main bearings, die-forged steel crankshaft
cylinder heads & valvetrain cast aluminium alloy; four valves per cylinder, 32 valves total, timing belt and simplex chain-driven (hybrid system) double overhead camshafts
fuel system, ignition system, engine management common rail multi-point electronic sequential indirect fuel injection with eight intake manifold-sited fuel injectors; Bosch Motronic electronic engine control unit (ECU); 98 RON/ROZ(93 AKI) EuroSuperPlus (premium) unleaded recommended for maximum performance and fuel economy
dimensions mass: depending on variant
DIN-rated motive power & torque outputs, ID codes
at 5,800 rpm; at 4,000 rpm — ABH
at 5,900 rpm; at 4,000 rpm — AEC
at 6,000 rpm; at 3,000 rpm — ABZ, AKG, ARS, ASG
at 6,600 rpm; at 3,500 rpm — AHK
at 6,600 rpm; at 3,500 rpm — AHC, AKH, AQJ
applications Audi V8 (ABH: 08/91-11/93), Audi C4 S4 (ABH: 10/92-07/94), Audi C4 S6 (AEC: 09/94-10/97), Audi C5 A6 (ARS: 04/99-05/01, ASG: 06/00-01/05), Audi D2 A8 (ABZ: 06/94-05/99, AKG: 06/97-12/98), Audi C4 S6 Plus (AHK: 06/96-10/97), Audi C5 S6 (AQJ: 09/99-05/01), Audi D2 S8 (AHC: 09/96-12/98, AKH: 08/97-12/98)
4.2 V8 40v 220-265kW
identification parts code prefix: 077
engine displacement & engine configuration 90° V8; bore x stroke: , stroke ratio: 0.91:1 – undersquare/long-stroke, 521.5 cc per cylinder; compression ratio: 11.0:1
cylinder block & crankcase cast aluminium alloy; five main bearings, die-forged steel crankshaft
cylinder heads & valvetrain cast aluminium alloy; five valves per cylinder, 40 valves total, timing belt and simplex chain-driven (hybrid system) double overhead camshafts
fuel system, ignition system, engine management two linked common rail fuel distributor rails, multi-point electronic sequential indirect fuel injection with eight intake manifold-sited fuel injectors; Bosch Motronic electronic engine control unit (ECU); 98 RON/ROZ(93 AKI) EuroSuperPlus (premium) unleaded recommended for maximum performance and fuel economy
DIN-rated motive power & torque outputs, ID codes
at 6,200 rpm; at 3,000 rpm — ARS, ASG
at 6,200 rpm; at 3,000 rpm — AUX, AWN
at 7,000 rpm; at 3,400 rpm — AQJ, ANK
at 7,000 rpm; at 3,400 rpm — AQH, AVP, AYS, BCS
applications Audi C5 A6 (ARS: 99-00, ASG: 00-04), Audi D2 A8 (AUX: 99-01, AWN: 01-02), Audi C5 S6 (AQJ: 99-01, ANK: 01-04), Audi S8 Plus (D2) (AQH: 05/99-02/01, AVP: 09/00-09/02, {Japan only – BCS: 09/00-02/01, AYS: 02/01-09/02})
4.2 V8 40v T 331-353kW (C5 RS6)
Based on the existing 4.2 V8 from the Audi C5 S6, this engine was tuned with the assistance of VW Group subsidiary Cosworth Technology (now MAHLE Powertrain), and featured two parallel turbochargers, known as 'biturbo', with two side-mounted intercoolers (SMICs). Enlarged and modified intake and exhaust ports on the new five valve cylinder heads, together with new induction and dual branch exhaust systems, a re-calibrated Motronic engine management system, revised cooling system, and decorative carbon fibre engine covers complete the upgrade.
The initial variant of this engine generates a specific power output of per litre displacement, and the 'RS6 Plus' variant gives per litre.
identification parts code prefix: 077.A
engine displacement & engine configuration 90° V8; bore x stroke: , stroke ratio: 0.91:1 – undersquare/long-stroke, 521.5 cc per cylinder; compression ratio: 9.8:1, two oil coolers – oil:water and oil:air, two or three (dependent on target market) coolant radiators
cylinder block & crankcase cast aluminium alloy; five main bearings, die-forged steel crossplane crankshaft with shared crankpins, two-part oil sump – upper: baffled cast alloy, lower: pressed steel, simplex roller chain driven oil pump
cylinder heads & valvetrain cast aluminium alloy; five valves per cylinder (three inlet, and two sodium-cooled exhaust valves), 40 valves total, low-friction roller-bearing finger cam followers with automatic hydraulic valve clearance compensation, timing belt and simplex roller chain-driven (hybrid system) hollow-tube double overhead camshafts (the crankshaft-driven timing belt operates both exhaust camshafts, which in turn individually chain-drive the inlet camshafts), variable inlet camshaft timing
aspiration two carbon fibre-cased siamesed air filters, two hot-film air mass meters, cast alloy intake manifold with Bosch 'E-Gas' drive by wire electronic throttle control valve, 'biturbo' – two fast-acting turbochargers (one per cylinder bank) with vacuum-actuated excess pressure control, two all-alloy side-mounted intercoolers (SMICs) optimised to prevent pressure loss
fuel system, ignition system, engine management fuel tank sited electric low pressure fuel lift pump, underfloor electric high pressure relay fuel pump, common rail multi-point electronic sequential indirect fuel injection with eight intake manifold-sited fuel injectors; eight individual single-spark ignition coils, NGK longlife spark plugs; Bosch Motronic ME 7.1.1 electronic engine control unit (ECU); 98 RON/ROZ(93 AKI) EuroSuperPlus (premium) unleaded recommended for maximum performance and fuel economy
exhaust system dual-branch exhaust pipes with metallic-element catalytic converters and secondary air injection, four lambda sensors, European EU3 emissions standard
DIN-rated motive power & torque outputs, ID codes & applications
at 5,700–6,400 rpm; at 1,950–5,600 rpm — BCY: Audi C5 RS6 (07/02-09/04)
at 6,000–6,400 rpm; at 1,950–6,000 rpm — BRV: Audi C5 RS6 Plus (04/04-09/04)
Diesel
3.3 V8 32v TDI CR 165kW
identification parts code prefix: 057.A; ID code: AKF
engine configuration & engine displacement 90° V8 engine, Turbocharged Direct Injection (TDI) turbodiesel; ; bore x stroke: , stroke ratio: 0.91:1 - undersquare/long-stroke, 416.0 cc per cylinder, compression ratio: 18.5:1, up to cylinder pressure,
cylinder block & crankcase compacted vermicular graphite cast iron (GJV/CGI); two-part cast aluminium alloy oil sump, five diameter main bearings, die–forged steel crossplane crankshaft with shared crankpins, diagonally split connecting rods, simplex roller chain-driven oil pump, pistons oil-cooled by cast-in cooling ducts
cylinder heads & valvetrain cast aluminium alloy; four valves per cylinder, 32 valves total, sliding-finger cam followers with automatic hydraulic valve clearance compensation, 2x hybrid-driven double overhead camshafts (2xDOHC - two overhead camshafts per cylinder bank - 'quad cam', inlet camshafts are driven from a front-sited timing belt from the crankshaft, exhaust camshafts are gear-driven at the rear from the inlet camshafts)
aspiration twin-turbo: two electronically controlled turbochargers with variable turbine geometry (VTG) (one turbo per cylinder bank), maximum absolute pressure, combined 4-part inlet manifold and air-to-water intercooler mounted within the vee. With additional side-mounted coolant radiator and additional electric coolant pump
fuel system & engine management (Common rail system) Low-pressure fuel lift pump mounted underneath the car turns on only when starter is being operated (when cranking); after that an electromagnetic valve bypass the pump. It uses a gear-type lift pump mounted on the passenger-side cylinder head driven by the camshaft; it is used to supply the high-pressure pump with sufficient pressure. Bosch CP3 high-pressure pump is used driven by the timing belt. Max rail pressure is 1350bar. Watercooled return line fuel cooler with an additional cooling pump (runs all the time) and side-mounted radiator and air-cooled return line cooler mounted on the bottom of the car. six-hole solenoid injection nozzles, CR electronic injection control. Dual Bosch EDC15 engine management computers running in master/slave configuration.
exhaust system vacuum-operated water-cooled exhaust gas recirculation, two catalysts, European EU3 emissions standard compliant
dimensions length: , width: , height:
DIN-rated power & torque output at 4,000 rpm; at 1,800-3,000 rpm
best specific consumption 205 g/kWh (41.1% energy efficiency)
application Audi D2 A8 quattro (12/99-09/02)
4.0 V8 32v TDI CR 202kW
When introduced in May 2003, this 3.9 litre V8 was the highest power and highest torque diesel V8 fitted in any production car worldwide. This was the second 'new' V engine from Audi which utilises new technologies - including chain-driven overhead camshafts and ancillary units, following the 4.2 40-valve V8 petrol engine first seen in the B6 S4. This engine was discontinued in July 2005, superseded by the bored-out and updated but fundamentally identical 4.2 V8 TDI.
identification parts code prefix: 057.B, ID code: ASE
engine configuration & engine displacement 90° V8 engine, Turbocharged Direct Injection (TDI) turbodiesel; , bore x stroke: , stroke ratio: 0.85:1 - undersquare/long-stroke, 492.1 cc per cylinder, cylinder spacing, compression ratio: 17.5:1, water-cooled alternator
cylinder block & crankcase compacted vermicular graphite cast iron (GJV/CGI); cast reinforcing bed-plate lower frame incorporating five main bearings with each bearing affixed by four bolts, three-part oil sump consisting of cast alloy upper section, a middle baffle section and pressed steel lower section, die–forged steel crossplane crankshaft with shared crankpins, diagonally fracture-split connecting rods, chain-driven ancillaries, oil filter module (incorporating oil separator and water-to-oil cooler) mounted within the 'vee'
cylinder heads & valvetrain cast aluminium alloy; four valves per cylinder, 32 valves total, operated by low-friction roller finger cam followers with automatic hydraulic valve clearance compensation, 2x double overhead camshafts (2xDOHC - two overhead camshafts per cylinder bank - 'quad cam') - the inlets driven in a relay method at the rear (flywheel) end of the engine by four simplex roller chains and the exhausts driven from the inlets by automatic slack adjusting spur gears at the front end, two unequal-length swirl-inducing switchable inlet ports, siamesed unequal-length exhaust ports
aspiration two air filters, two hot-film air mass meters, 'biturbo': two water-cooled Garrett GT1749 turbochargers with electrically actuated Variable Turbine Geometry (VTG) (one turbo per cylinder bank) operating up to 210,000 rpm with a maximum boost of , two air-to-air fan-assisted side-mounted intercoolers (SMICs), two separate cast alloy intake manifolds interconnected by a "feedthrough" system to equalise the turbo boost pressure in the two cylinder banks, two-position variable swirl flaps integrated into the intake tract
fuel system & engine management electric low-pressure fuel lift pump, one toothed belt driven injection pump, one central fuel distributor supplying two common rail (CR) fuel rails (one per cylinder bank), Bosch solenoid-valve injectors with seven-hole nozzles for homogenous fuel delivery, single and double pilot injection; Bosch EDC16 electronic engine control unit (ECU)
exhaust system twin water-cooled exhaust gas recirculation (mounted within the 'vee'), air-gap insulated fan-branch alloy steel exhaust manifolds, two close-coupled primary catalytic converters plus two main underfloor converters, Euro3 emissions standard
dimensions length: , mass:
DIN-rated power & torque output ; at 1,800-2,500 rpm
application Audi D3 A8 4.0 TDI quattro (05/03-07/05)
Current production engines
Gasoline
Of their eight-cylinder petrol engines, all Volkswagen Group V8 engines are primarily constructed from a lightweight cast aluminium alloy cylinder block (crankcase) and cylinder heads. They all use multi-valve technology, with the valves being operated by two overhead camshafts per cylinder bank (sometimes referred to as 'quad cam'). All functions of engine control are carried out by varying types of Robert Bosch GmbH Motronic electronic engine control units.
These V8 petrol engines initially were only used in cars bearing the Audi marque, but are now also installed in Volkswagen Passenger Cars 'premium models'. They are all longitudinally orientated, and with the exception of the Audi R8, are front-mounted.
4.2 V8 FSI 32v
Based on the existing Audi 40 valve V8, this new engine is heavily revised over its predecessor, with all-new components including: crankshaft, connecting rods and pistons, cylinder heads, and valvetrain, oil and cooling system, intake and exhaust system, and engine management system. It is available in two versions; a basic or 'comfort' version, first used in the Audi Q7; and a sports-focussed high-revving version, with features borrowed from motorsport, for the B7 RS 4 quattro and the R8. This is the first eight-cylinder road car engine to use Fuel Stratified Injection (FSI), which was successfully developed by Audi in their Le Mans-winning R8 racing car. The 5.2 V10 FSI was developed directly from this V8 engine.
identification parts code prefix/variant: 079.D
displacement & configuration 90° V8 engine; cylinder bank offset; cylinder spacing; bore and stroke: , stroke ratio: 0.91:1 – undersquare/long-stroke, 520.4 cc per cylinder, compression ratio: 12.5:1, firing order: 1–5–4–8–6–3–7–2; water:oil lubricant cooler (RS 4/R8 utilises an additional thermostatically controlled air:oil cooler); Q7 and RS 4 utilise a wet sump system (RS 4 with additional longitudinal axis flapped baffles controlled by lateral g-force), R8 uses dry sump
cylinder block & crankcase homogeneous monoblock low-pressure chill gravity die casting hypereutectic 'Alusil' aluminium-silicon alloy (AlSi17Cu4Mg) with a closed-deck design, mechanically stripped hard silicon crystal integral liners, honed under simulated mechanical stress; reinforced by a cast lower crankcase alloy bedplate (AlSi17Cu4Mg) mimicking a ladder-frame design, and including five GGG50 nodular cast iron press-fit main bearing caps each attached by four bolts; overall length, cylinder block height; two-stage 3/8" simplex roller chain and gear driven 'accessory drive' which includes the oil pump, water pump, power steering pump, and air conditioning compressor; baffle-plate sump
crankshaft, connecting rods and pistons die-forged and tempered high alloy steel (42CrMoS4) 90° crankshaft with diameter and width main bearing journals and diameter and width big end bearing journals; long high strength forged cracked trapezoidal connecting rods (36MnVS4 in basic engine, ultra high strength 34CrNiMo8 in RS 4/R8 with more restrictive geometry tolerances); forged aluminium pistons with shaped piston crowns designed to impart charged volume tumbling effect for fully homogeneous air/fuel charge
cylinder heads & valvetrain cast aluminium alloy, partition-plate horizontally divided intake ports producing a tumble effect (larger cross-section on RS 4/R8); four valves per cylinder: chrome-plated solid-stem (hollow-stem on RS 4/R8) intake valves, and chrome-plated sodium-filled hollow-stem exhaust valves, both with valve lift (longer valve lift on RS 4/R8), 32 valves total; lightweight low-friction roller finger cam followers (uprated with peened rollers on RS 4/R8) with automatic hydraulic valve clearance compensation, double overhead camshafts (each a hollow tube composite) on each cylinder bank, driven from the flywheel side via a two-stage chain drive using three 3/8" simplex roller chains (sleeve-type on RS 4/R8), valve opening (in crank angle degrees) 200 intake (230 for RS 4/R8) and 210 exhaust (230 for RS 4/R8); valve overlap facilitates integral exhaust gas recirculation; continuous hydraulic vane-adjustable variable valve timing for intake and exhaust camshafts with up to 42 degrees adjustment, each controlled via information from Hall sensors, Audi "RS" 'red' plastic cam covers on RS 4, 'anthracite' plastic on R8
aspiration two single-entry air filters each with hot-film air mass flow meters (Q7), or triple-entry single air filter with single hot-film air mass meter (RS 4), or double-entry dual-element single air filter with two hot-film air mass flow meters (R8); single (Q7 & RS 4) or twin (R8) cast alloy throttle body electronically controlled Bosch E-Gas throttle valves (Bosch diameter on Q7, Pierburg diameter on RS4), two-stage four-piece gravity die-cast (Q7) (sand-cast on RS 4/R8) magnesium-aluminium alloy variable length intake manifold with electronically map-controlled silicon tipped tract-length flaps along with tumble flaps inducing a swirling movement in the drawn air (RS 4 & R8 do not use a variable tract-length intake manifold)
fuel system fully demand-controlled, (Q7 returnless, RS 4 return to tank); fuel tank–mounted low-pressure fuel pump; Fuel Stratified Injection (FSI): two inlet camshaft double-cam driven single-piston high-pressure injection pumps maintaining a pressure of between in the two stainless steel common rail fuel distributor rails, eight combustion chamber sited direct injection solenoid-controlled 65 volt single-hole sequential fuel injectors with integrated swirl plates; 98 RON/ROZ (93 AKI) EuroSuperPlus (premium) unleaded recommended for maximum performance and fuel economy (95 RON (91 AKI) may be used, but will reduce performance and worsen fuel economy)
ignition system & engine management mapped direct ignition with centrally mounted longlife spark plugs and eight individual direct-acting single spark coils; Bosch Motronic MED 9.1.1 electronic engine control unit (ECU) (two MED 9.1 ECUs in the RS 4 and R8, working on the 'master and slave' concept due to the high revving nature of the engine), four knock sensors, EU4 emissions standard, map-controlled coolant thermostat (Q7 only), additional electric after-run coolant pump with two additional side-mounted radiators (RS 4/R8), water-cooled alternator, two map-controlled radiator fans
exhaust system vacuum-controlled secondary air injection to assist cold start operation; air-gap insulated exhaust manifold per cylinder bank (Q7), or 4-into-2-into-1 fan-branch exhaust manifold per cylinder bank to minimise reverse pulsation of expelled exhaust gases (RS 4), or fan branch manifold with integrated catalytic converter per cylinder bank; two close-coupled and two main underfloor catalytic converters – ceramic on Q7, high-flow metallic on RS 4, or main catalytic converter integrated into transverse main rear silencer with quad outlets; four heated oxygen (lambda) sensors (broadband upstream, nonlinear downstream) monitoring pre- and post-catalyst exhaust gases; siamesed absorption-type middle silencer (Q7 with crossover) and siamesed rear silencer, separate rear silencers on RS 4 with vacuum-operated flap valves
dimensions Q7 (for auto transmission with plate-type flywheel): approx. , RS4 (for 6-speed manual with dual-mass flywheel): approx.
DIN-rated power & torque outputs, ID codes, applications
at 6,800 rpm; at 3,500 rpm, 85% available from 2,000 rpm — BAR: Audi Q7 (03/06-05/10), Volkswagen Touareg (06/06-05/10); BVJ: Audi C6 A6 (05/06-08/11), Audi D3 A8 (06/06-07/10)
at 7,000 rpm — CAU: Audi S5 (06/07-03/12)
or at 7,800 rpm; at 5,500 rpm, 90% available between 2,250 and 7,600 rpm, 8,250 rpm rev limiter — BNS: Audi RS 4 (B7) (09/05-06/08); BYH: Audi R8 (04/07-09/10; -02/15 for facelift model with 430-hp engine)
at 8,250 rpm; at 4000–6000 rpm, 90% available between 2,250 and 7600 rpm, 8,500 rpm rev limiter — CFSA: Audi RS 4 (B8) (06/12-09/15); Audi RS 5 (06/2010-09/17)
Awards
was placed in the 2005 and 2006 annual list of Ward's 10 Best Engines
4.2 V8 40v
identification parts code prefix: 079
engine displacement & engine configuration 90° V8 engine; cylinder spacing; bore x stroke: , stroke ratio: 0.91:1 – undersquare/long-stroke, 520.4 cc per cylinder
cylinder block & crankcase homogeneous monobloc low-pressure gravity die cast hypereutectic 'Alusil' aluminium-silicon alloy (AlSi17Cu4Mg) with a closed-deck design, mechanically stripped hard silicon crystal integral liners, honed under simulated mechanical stress; five main bearings; die-forged steel crankshaft
cylinder heads & valvetrain cast aluminium alloy, five valves per cylinder, 40 valves total; lightweight low-friction roller cam followers with automatic hydraulic valve clearance compensation, roller chain-driven double overhead camshafts
aspiration synthetic material two-stage variable intake manifold
fuel system & engine management two linked common rail fuel distributor rails, multi-point electronic sequential indirect fuel injection with eight intake manifold-sited fuel injectors; Bosch Motronic ME 7.1.1. electronic engine control unit (ECU); 98 RON/ROZ (93 AKI) EuroSuperPlus (premium) unleaded recommended for maximum performance and fuel economy
exhaust system two multi-stage catalytic converters
dimensions length: , mass:
DIN-rated motive power & torque outputs, ID codes
at 6,600 rpm; at 3,500 rpm, 6,800 rpm max — Audi A6, BAT, A8: BFM (BFM engine is belt driven)
at 6,200 rpm; at 2,700–4,600 rpm, 6,500 rpm max — Audi A6 allroad: BAS
at 7,000 rpm; at 3,500 rpm — Audi S4: BBK (03/03-03/09)
at 7,200 rpm; at 3,000 rpm — Audi S4: BHF (03/03-03/09 – US/Korea only)
at 6,500 rpm; at 2,800-3,700 rpm — Volkswagen Phaeton: BGH, BGJ (Belt driven)
applications Audi B6 S4, Audi B7 S4, Audi C5 A6 allroad (BAS: 07/02-08/05), Audi C6 A6 (BAT: 05/04-05/06), Audi A8 (BFM: 10/02-07/10), Volkswagen Phaeton (BGJ: 05/03-07/03, BGH: 08/03-05/10)
Awards
was placed in the 2004 annual list of Ward's 10 Best Engines
4.0 TFSI
This engine is part of Audi's modular 90° V6/V8 engine family. It shares its bore and stroke, 90° V-angle, and 90mm cylinder spacing with the Audi V6. The earlier V6 engines (EA837) used an Eaton TVS Supercharger instead of turbocharger(s). In 2016, Audi and Porsche released a new turbocharged V6 engine they dubbed EA839. These 2.9L (biturbo) & 3.0L (single turbo) V6 engines share the 4.0T TFSI V8's “hot vee” design, meaning the turbo(s) are placed in the Vee of the engine (between each bank of cylinders) instead of on the outside of each cylinder bank. This allows the turbocharger(s) to produce boost pressure more quickly as the path the exhaust gases travel is much reduced. It also aids in getting the engine's emissions hardware up to temperature more quickly. As with the V6, the V8 is used in various Audi and Porsche models, but the V8 also finds use in Bentley and Lamborghini vehicles.
engine displacement & engine configuration 90° V8 engine; cylinder spacing; bore x stroke: , stroke ratio: 0.95:1 – undersquare/long-stroke, 499.1 cc per cylinder, compression ratio: 10.5:1
fuel system; Fuel Stratified Injection (FSI) Central-Overhead Injectors
exhaust system two twin-scroll turbo chargers and twin air- and water-cooled intercoolers
DIN-rated motive power & torque outputs, ID codes, applications
at 5,500 rpm; from 1,400 rpm to 5,400 rpm— CEUC: Audi S6 C7, S7, CEUA: A8 D4
at 5,800 rpm; from 1,400 rpm to 5,300 rpm— CTGA: A8 D4, A8 D5
at 5,700 rpm; from 1,750 rpm to 5,500 rpm— CRDB, CWUB: Audi RS6 C7 and RS7
at 6,200 rpm; from 1,700 rpm to 5,500 rpm (overboost to 750 Nm) — DDTA: Audi S8 Plus (D4), CWUC: Audi RS7 Performance, Audi RS6 Performance (C7)
at 6,000 rpm; from 1,700 rpm in Porsche Panamera GTS
at 6,000 rpm; from 1,700 rpm in Porsche Panamera Turbo
at 6,000 rpm; from 1,700 rpm in Porsche Panamera Turbo S
at 6,000 rpm; from 1,700 rpm in Porsche Panamera Turbo S E-Hybrid
at 6,000 rpm; from 1,700 rpm in Bentley Continental GT V8 and Flying Spur V8
at 6,000 rpm; from 1,700 rpm in Bentley Continental GT V8 S
at 6,000 rpm; in Bentley Continental GT V8 (2019–)
478 kW (650 PS; 641 bhp) at 6,000 rpm; 850 N⋅m (627 lbf⋅ft) in Lamborghini Urus
471 kW (640 PS; 631 bhp) at 6,000 rpm; 850 N⋅m (627 lbf⋅ft) in Porsche Cayenne Coupé Turbo GT
575 kW (782 PS; 771 bhp) at 6,000 rpm; 1,000 N⋅m (738 lbf⋅ft) in Bentley Continental GT Speed
Audi version of the engine includes electronic monitoring of the oil level, while the Bentley engine includes a dipstick for an oil check. In addition, the Bentley engine uses switchable hydraulic mounts instead of Audi's active electrohydraulic engine mounts. The Bentley engine does not include a stop-start system.
Diesel
4.2 V8 TDI CR 235-257kW
This Audi engine is an entirely redeveloped and bored-out evolution of the superseded 4.0 V8 TDI CR, now with cylinder spacing between bore centres, and again with roller chain drive for the overhead camshafts and ancillaries. Just like its 4.0 V8 TDI predecessor, this all-new 4.2 V8 TDI retains the mantle of the world's highest power output car with a diesel V8. This engine is manufactured at Győr, Hungary by AUDI AG subsidiary Audi Hungaria Motor Kft.
identification parts code prefix: 057.C
engine configuration & engine displacement 90° V8 engine, Turbocharged Direct Injection (TDI) turbodiesel; ; bore x stroke: , stroke ratio: 0.87:1 - undersquare/long-stroke, 516.7 cc per cylinder, cylinder spacing, compression ratio: 16.5:1, water-cooled alternator
cylinder block & crankcase compacted vermicular graphite cast iron (GJV/CGI), ; UV laser-honed exposed bore; cast reinforcing bed-plate lower frame incorporating five main bearings (each 'bearing' affixed by four bolts), die-forged chrome molybdenum alloy steel crossplane crankshaft with first and second order forces and moments avoided, three-part oil sump consisting of cast alloy upper section, a middle baffle section and pressed steel lower section, diagonally fracture-split connecting rods, cast aluminium alloy Kolbenschmidt pistons (Mahle on CCFA), simplex roller chain-driven ancillaries, oil filter module (incorporating oil separator and water-to-oil cooler) mounted within the 'vee' (externally mounted on Marine variants)
cylinder heads & valvetrain cast aluminium alloy; four valves per cylinder, 32 valves total, operated by low-friction roller finger cam followers with automatic hydraulic valve clearance compensation, double overhead camshafts - the inlets driven in a relay method at the rear (flywheel) end of the engine by four simplex roller chains and the exhausts driven from the inlets by automatic slack adjusting spur gears at the front end, two unequal-length swirl-inducing switchable inlet ports, siamesed unequal-length exhaust ports
aspiration - automotive two air filters, two hot-film air mass meters, 'biturbo': two water-cooled turbochargers with electrically direct-actuated Variable Turbine Geometry (VTG) vanes (one turbo per cylinder bank) operating up to 226,000 rpm with a maximum electrically regulated boost of , two side-mounted air-to-air fan-assisted (not on Q7) intercoolers (SMICs), two separate cast alloy intake manifolds interconnected by a "feedthrough" system to equalise the pressure in the two cylinder banks, two-position variable swirl flaps integrated into the intake tract. Engines introduced from 2014 include 2 variable geometry turbocharger with maximum of relative boost pressure.
aspiration - Marine air filter with hot-film air mass meter, one water-cooled turbocharger with electric boost pressure control mounted within the vee, sea-water tube intercooler, two separate cast alloy intake manifolds interconnected by a "feedthrough" system to equalise the pressure in the two cylinder banks, two-position variable swirl flaps integrated into the intake tract
fuel system & engine management common rail (CR) direct diesel injection: electric low-pressure fuel lift pump, one timing belt-driven injection pump, two common rail fuel rails (one per cylinder bank), piezo-electric operated fuel injectors with eight-hole nozzles for homogenous fuel delivery, single and double pilot injection, up to four main injection actuations per piston cycle; Bosch EDC16 CP electronic engine control unit (ECU), Bosch MDC Marine Diesel Control on Marine variant. Engines introduced from 2014 has increased fuel pressure to .
exhaust system two air-gap insulated fan-branch alloy steel exhaust manifolds, two close-coupled maintenance-free oxidizing catalytic converters, two silicon carbide diesel particulate filters, Euro4 emissions standard compliant
dimensions length: , mass: (automotive - lighter than its 4.0 V8 TDI predecessor, lighter than the all-aluminium alloy Mercedes-Benz 4.0 V8 CDI diesel engine), (Marine variant: dry weight, including DMF, cooling system & all ancillaries)
DIN-rated power & torque outputs, ID codes
BMC:
BVN: at 3,750 rpm; at 1,600-3,500 rpm
BTR: at 3,750 rpm; at 1,800-2,500 rpm
CCFA:
CEM: at 4,200 rpm; at 1,900 rpm
CTEC: at 3,750 rpm; at 2,000-2,750 rpm
applications
Audi D3 A8 4.2 TDI quattro (BMC: 01/05-06/05, BVN: 07/05->), Audi Q7 4.2 TDI (BTR: 03/07-06/09, CCFA: 06/09->), Volkswagen Marine TDI 350-8 (CEM: 02/09->), Volkswagen Touareg, Porsche Cayenne
4.0 V8 TDI 310-320kW
A successor to the 4.2 TDI. The engine includes 2 turbochargers, 48-volt electrical system, 7 kW electric compressor, Bosch CRS 3.25 engine management.
A turbocharger serves to supply engine boost and spools up the passive turbocharger.
identification
parts code prefix: EA 898
engine configuration & engine displacement 90° V8 engine, Turbocharged Direct Injection (TDI) turbodiesel; ; bore x stroke: , stroke ratio: 0.91:1 - undersquare/long-stroke, 494.5 cc per cylinder, cylinder spacing, compression ratio: 16.0:1, water-cooled alternator
DIN-rated power and torque outputs, applications, ID codes
at 3,500-5,000 rpm; at 1,000-3,250 rpm, Porsche Panamera II 4S Diesel
at 3,750-5,000 rpm; at 1,000-3,250 rpm, Audi SQ7 2016-2020, Audi SQ8 2019-2020, Audi A8 D5, Bentley Bentayga,2020-
VW Touareg
Production
The engine was developed in Ingolstadt.
15.6 V8 DC16 368-544kW (Scania)
engine configuration & engine displacement 90° V8 engine, turbodiesel; ; bore x stroke: , stroke ratio: 0.82:1 - undersquare/long-stroke, 1,950.8 cc per cylinder
aspiration turbocharger, intercooler
fuel system & engine management Scania PDE high-pressure Unit Injector system, Scania selective catalytic reduction (SCR) - catalytic converter with AdBlue urea injection
DIN-rated power & torque outputs - Euro4
at 1,900 rpm; at 1,100-1,400 rpm
at 1,900 rpm; at 1,100-1,400 rpm
at 1,900 rpm; at 1,100-1,400 rpm
DIN-rated power & torque outputs - Euro5
at 1,800 rpm; at 1,000-1,350 rpm
at 1,900 rpm; at 1,000-1,400 rpm
at 1,900 rpm; at 1,000-1,400 rpm
at 2,000 rpm; at 1,000-1,400 rpm reference: https://web.archive.org/web/20121112032602/http://www3.scania.com/en/New-V8-truck-range/The-new-730hp-engine/
applications Scania trucks
Racing engine
The race version of the engine was developed and produced for the Deutsche Tourenwagen Meisterschaft, between 1990 and 1992; and later the Deutsche Tourenwagen Masters and in the Audi R8C, Audi R8R, Audi R8 and Bentley Speed 8, between 1999 and 2018.
Audi V8
Audi developed a Group A competition version of the Audi V8 engine for entry into the Deutsche Tourenwagen Meisterschaft (DTM) (German Touring Car Championship) auto racing series equipped with a , later , 3.6 V8 engine and 6-speed manual transmission, and began racing with it in 1990 with Schmidt MotorSport (SMS) running the operation, and Hans-Joachim Stuck, Walter Röhrl and Frank Jelinski driving.
Audi R8C/R8R engine
The R8C and R8R both use 3.6-liter, twin-turbocharged V8 engines, producing between , and between of torque, while using two air restrictors, and pushing of absolute boost pressure. While the R8R has a large number of vents placed on the nose, most of the intakes and air exits on the R8C are placed on the sides.
The R8R was estimated to boast around from its V8 engine, allowing it to hit in 1999 at Le Mans (the original claims were that the car could go ).
Audi R8 engine
The R8 is powered by a 3.6 L Audi V8 with Fuel Stratified Injection (FSI), which is a variation on the concept of gasoline direct injection developed by VW; it maximizes both power and fuel economy at the same time. FSI technology can be found in products available to the public, across all brands in the Volkswagen Group.
The power supplied by the R8, officially listed at about in 2000, 2001, and 2002, in 2003 and 2004, and in 2005, is sent to the rear wheels via a Ricardo six-speed sequential transmission with an electropneumatic paddle shift. Unofficially, the works team Audi R8 for Le Mans (2000, 2001, and 2002) is said to have had around instead of the quoted 610 hp. The numbers were quoted at speed, and were due to the car making 50 extra horsepower due to twin ram-air intakes at speeds over . Official torque numbers were quoted for this version of the engine at at 6500 rpm (2004/2005), but the 2002/2003-spec engine produced more torque; with at 5500 rpm, with boost pressure set at absolute. The equation for horsepower (torque divided by 5250, multiplied by rpm) for these numbers produces a horsepower rating of at the same 6500 rpm (516/5250*6500=638).
Restrictor changes for 2003 brought the power down to 550 bhp for anyone still racing with the R8, but the maximum torque hardly changed.
For 2005, The ACO still felt that the R8 needed to be kept in check, so they reduced the restrictor size on the R8's engine, due to the car not meeting new hybrid regulations, and stipulated the car shall carry ballast weight in an attempt to make the races more competitive. The R8 was restricted even further to only 520 bhp.
Bentley Speed 8/EXP Speed 8 engine
The engine from the Audi R8, a 3.6-liter V8, with (Honeywell Turbo Technologies) turbocharger, was used as the initial powerplant for the Bentley in 2001. It produced and over of torque, via two intake restrictor, with boost pressure limited to by regulations.
Following its initial year of competition, the Audi-sourced V8 was modified to better suit the EXP Speed 8. This saw the engine expand to 4.0 liters, producing between , and of torque, using two intake restrictor plates, with boost pressure still being limited to by regulations. This would ultimately lead to Bentley redesigning the car for 2003, leading to the change of name to simply Speed. Without the intake restrictor plates (completely unrestricted), and with boost pressure set at around , the 4.0-liter engine is reportedly capable of producing up to , and about of torque.
Audi DTM V8 engine
The Audi DTM V8 engine family is a series of prototype, four-stroke, 3.6-liter to 4.0-liter, naturally aspirated V-8 racing engines, developed and produced by Audi for the Deutsche Tourenwagen Meisterschaft, between 1990 and 1992; and later the Deutsche Tourenwagen Masters, between 2000 and 2018.
Audi V8 DTM
Audi developed a Group A competition version of the Audi V8 engine for entry into the Deutsche Tourenwagen Meisterschaft (DTM) (German Touring Car Championship) auto racing series equipped with a , later , 3.6 V8 engine and 6-speed manual transmission, and began racing with it in 1990 with Schmidt MotorSport (SMS) running the operation, and Hans-Joachim Stuck, Walter Röhrl and Frank Jelinski driving.
Audi TT-R DTM
The Audi TT-R DTM uses a Audi naturally-aspirated V8 engine in partnership with Neil Brown Engineering for development, building, assembly, maintenance and tune-up role, it has a power output of approximately @ 6,800 rpm and a maximum torque of about @ 6,000 rpm, while using two air intake restrictors.
Audi A4 DTM
The Audi A4 DTM is powered by a Audi naturally-aspirated V8 engine in partnership with Neil Brown Engineering for development, building, assembly, maintenance and tune-up role, it has a power output of approximately and a maximum torque of more than .
Audi A5/RS5 DTM
The A5 DTM was still fitted with a V8 engine that used in a previous Audi A4 DTM and Abt-Audi TT DTM were built jointly by Audi and Neil Brown Engineering (NBE) rated at and coupled to a 6-speed transmission grafted from the previous A4 DTM car, while using a Bosch MS 5.1 ECU.
After the 2012 season, the vehicle was renamed RS5 DTM, corresponding with the Audi RS5 production model. It is powered by a naturally-aspirated engine and 2x DOHC camshafts. The engine itself is a custom-built Audi 4.0 L V8, with four valves per cylinder, and a 90-degree V-angle. It now has a power output of over and torque of over . Front engined and longitudinally mounted engine mounting layout, the RS5's engine is indirect fuel injected. The RS5 DTM's ECU is a Bosch Motronic MS 5.1 and other components such as the CDI ignition are also supplied by Bosch.
Applications
Audi V8 DTM
Abt-Audi TT-R DTM
Audi R8C
Audi R8R
Audi R8
Bentley Speed 8
Audi A4 DTM
Audi 5 Series DTM
References
Further reading
Volkswagen Group engines
V8 engines
Audi engines
Bentley engines
Lamborghini engines
Gasoline engines by model
Diesel engines by model
Engines by model
Piston engines
Internal combustion engine | Volkswagen-Audi V8 engine | [
"Technology",
"Engineering"
] | 10,600 | [
"Internal combustion engine",
"Engines",
"Engines by model",
"Piston engines",
"Combustion engineering"
] |
69,131,064 | https://en.wikipedia.org/wiki/Space%20Concordia | Space Concordia, commonly referred to as SC, is a student organisation at Concordia University in Montreal, Canada, dedicated to the development of space technology and teaching students about space related sciences.
Over 150 members are organized in four divisions.
Space Concordia's Rocketry division is currently competing in the Base 11 Space Challenge, developing a liquid fuelled rocket with the goal to cross the Kármán line.
The development and most of the manufacturing is done in-house by students, including the construction of the mobile engine test stand Trailer Tom.
History
Space Concordia was founded in 2010 by assistant professor Scott Gleason at Concordia University with the purpose of competing in the Canadian Satellite Design Challenge (CSDC). The team had less than ten members then. Their entry in the competition, the satellite Consat-1, won first place. The team working on satellites became later the Spacecraft division of Space Concordia.
In 2012 Rocketry and Robotics divisions were founded. Robotics builds rovers and Rocketry is dedicated to the construction of rockets.
Rocketry division's first rocket ever, Arcturus, was awarded 2nd place in the payload category of the 10th Intercollegiate Rocket Engineering Competition (IREC) in 2015. The solid rocket reached a height of .
In 2016, Space Concordia won 2nd place in the basic category of the 11th IREC.
In 2018, the rocket Supersonice reached a height of and a top speed of mach 1.8. Space Concordia's first supersonic rocket won first place in the Spaceport America Cup.
Later in 2018, Rocketry started development of a liquid fuelled rocket to compete in the Base 11 Space Challenge. Space Concordia won second place in the design phase and first place in the Critical Design Review (CDR).
On June 18 2021, they successfully completed a hot-fire test of the engine. Space Concordia fired the most powerful liquid fuelled student rocket engine, producing an average thrust of 35 kN at ground level.
Divisions
Space Concordia is organised in four divisions: Robotics, Rocketry, Spacecraft and Space Health.
Rocketry Division
Space Concordia Rocketry Division, commonly abbreviated as SCRD, focuses on the design, development and testing of liquid rockets.
Since 2018 Space Concordia Rocketry Division has been developing a liquid rocket known as "StarSailor". This rocket is designed to fly to the Kármán line. The rocket is powered a pressure-fed Kerosene-Liquid Oxygen rocket which currently holds the Canadian record for highest thrust produced by amateur rocketry teams in Canada.
Facilities
Space Concordia’s club room, commonly referred to as 'Space Lab', is located on the 9th floor of the Henry F. Hall Building on Concordia’s downtown campus.
Space Concordia’s members have also access to the 'Cage', an area in the basement of the Henry F. Hall Building, used by different clubs and capstone students. The Cage is used for manufacturing, and storing equipment and parts.
Concordia’s Engineering Design and Manufacturing Lab (EDML) is used by members to manufacture parts that require machining. The EDML is also located in the basement of the Henry F. Hall Building. It is supervised by university staff members, who also assist and train students. The lab is equipped with manual drills, mills, lathes and a welding area.
Awards By Division
Spacecraft Division
2012 1st price in the first Canadian Satellite Design Challenge (CSDC)
2016 1st place in the third Canadian Satellite Design Challenge (CSDC)
Rocketry Division
2016 2nd place in the basic category of the 11th IREC
2018 1st place in 30k ft category of the Spaceport America Cup
2019 2nd place in design review of the Base 11 Space Challenge
2021 1st place in the Critical Design Review (CDR) of the Base 11 Space Challenge
Rockets
Space Concordia has built and launched four rockets so far.
Arcturus (2015)
Aurelius (2016)
Maurice (2017)
Supersonice (2018)
StarSailor (2018-Present)
See also
Concordia University
Delft Aerospace Rocket Engineering
Spaceport America Cup
Liquid-propellant rocket
WARR (TUM)
References
External links
Space Concordia - Space & Aerospace Student Organization
Experimental Sounding Rocket Association
Base 11 Space Challenge
Concordia University
Rocketry | Space Concordia | [
"Engineering"
] | 843 | [
"Rocketry",
"Aerospace engineering"
] |
69,132,487 | https://en.wikipedia.org/wiki/%282-Hydroxyethyl%29%20dimethylsulfoxonium%20chloride | (2-Hydroxyethyl) dimethylsulfoxonium chloride is an organic compound with the formula . It is a sulfonium ion with a chloride counterion. The cation has been isolated from sea chervils and sea sponges. It causes the Dogger Bank itch.
Properties
(2-Hydroxyethyl) dimethylsulfoxonium chloride is colourless. It dissolves in dioxane, methanol, chloroform or water.
(2-Hydroxyethyl) dimethylsulfoxonium chloride is a salt, with a sulfur atom having a positive charge. Attached to the sulfur are two methyl groups, and oxygen atom, and an ethoxy group attached at the number 2 carbon. Its structure has been confirmed by X-ray crystallographys.
Natural occurrence
(2-Hydroxyethyl) dimethylsulfoxonium has been discovered so far in invertebrate animals in the genus Alcyonidium and a single species of sea sponge.
References
Sponge toxins
Sulfonium compounds
Chlorides
Primary alcohols
Invertebrate toxins | (2-Hydroxyethyl) dimethylsulfoxonium chloride | [
"Chemistry"
] | 236 | [
"Chlorides",
"Inorganic compounds",
"Salts"
] |
69,132,792 | https://en.wikipedia.org/wiki/Environmental%20racism%20in%20the%20United%20States | Environmental racism is a form of institutional racism, in which people of colour bear a disproportionate burden of environmental harms, such as pollution from hazardous waste disposal and the effects of natural disasters. Environmental racism exposes Native Americans, African Americans, Asian Americans, Pacific Islanders, and Hispanic populations to physical health hazards and may negatively impact mental health. It creates disparities in many different spheres of life, such as transportation, housing, and economic opportunity.
Communities of color are more likely to be located next to pollution sources, such as landfills, power plants, and incinerators. There is evidence that exposure to pollution can result in a higher prevalence of disease. Additionally, low-income communities of color are more likely to have polluted water. An analysis of EPA data found that unequal access to safe drinking water is strongly correlated with race. The most polluted communities tend to be those with high poverty, inadequate infrastructure, substandard schools, chronic unemployment, and poor healthcare systems. Empirical evidence suggests environmental hazards negatively affect nearby property values, employment opportunities, and economic activities. In addition, environmental hazards can cause psychological stress.
Natural disasters also tend to have unequal impacts on communities of color. The extent of poverty within a region can often have a much stronger effect on the scale of a natural disaster's impact than the severity of the disaster itself. Affluent, white communities tend to be located on higher ground, so they are less vulnerable to floods than communities of color. Moreover, disaster prevention and recovery plans are often biased against minorities in low-income areas.
History
The origins of the environmental justice movement can be traced to the Indigenous environmental movement, which itself has roots in over 500 years of colonialism, oppression, and ongoing struggles for sovereignty and land rights. In 1968, grassroots environmental activists from several tribal nations met in Minnesota and formed an organization known as the American Indian Movement (AIM).
The 1982 North Carolina PCB Protest is widely recognized as the origin of the environmental justice movement. In 1982, North Carolina state officials decided to place a landfill with highly toxic PCB-contaminated soil in the small town of Afton in Warren County, North Carolina. Afton was about 84% African American. This decision sparked the first national protest against the location of a hazardous waste facility. Organized by the National Association for the Advancement of Colored People, residents of Warren County, along with local civil rights and political leaders, gathered in opposition to the placement of the landfill site. Over 500 protesters were arrested. In response, two major studies were published: the US General Accounting Office 1983, and the United Church of Christ 1987. Both studies found that there was a strong relationship between race and the location of hazardous waste facilities.
The US General Accounting Office study conducted a survey of the locations of hazardous-waste facilities, and found that these facilities were more likely to be located in minority and low-income communities. The United Church of Christ Commission for Racial Justice (CRJ) study found that three of the largest hazardous waste facilities were located in primarily Black areas, and accounted for 40% of the hazardous-waste landfill capacity in the United States. The study also found that the strongest predictor of the placement of hazardous waste facilities was race, surpassing both household income and home values. An additional study conducted by the CRJ found that three out of five African Americans and Hispanic Americans lived in communities with hazardous waste sites.
Pollution
Agriculture
Concentrated animal feeding operations (CAFOs) contribute to the adverse health effects experienced by EJ communities by releasing harmful gas emissions into the air (ammonia, volatile organic compounds, endotoxins, etc.) greatly reducing the surrounding air quality. Some ways that these chemicals pollute the air are through barns that contain animals, the storage of waste specially hog operations, handling the wasted stored These pollutants in the air are able to carry and transmit disease-causing bacteria and certain fungi. They can also pollute the soil and nearby water sources. The most common adverse effects of CAFOs in humans are increased asthma and reduced lung function.
Methane emission is emitted and produced from organic compounds found in industrial wastewater and from the breakdown of animal manure, usually pigs, cows, and goats. Even when looking at a small scale, each animal's contribution is huge, one cow is able to produce up to 264 pounds of methane gas per year. While methane emissions from animals can cause adverse health effects, another important aspect to look at is the fact it is driving climate change. Climate change in EJ communities is the most impacted, not having the all the resources they need. Weather events in these communities are becoming more severe and dangerous, the agricultural industry is the biggest contributor of methane in the United States.
Pesticides have been used for thousands of years worldwide, in the United States most of the pesticide use is in agriculture. People and the families of people that work as a farmworker or as an agricultural worker are at the highest risk of the effects of these chemicals. Eighty-three percent of farmworkers identify themselves as Hispanic and one-third of all farmworkers have an income below the federal poverty line. From previous federal policies and racist lending practices have ensured that most of the farmlands in the United States are owned and operated by whites and has ensured that BIPOC and people living in low-income areas are the ones mostly impacted by pesticide pollution. According to research that was conducted in California; pesticide pollution has the greatest income, racial, and ethnic inequality in the state. While this research was done in California, this is unfortunately the case across the United States, BIPOC are the most impacted. The impacts that pesticides have on human health are dependent on the type that is used in that area, such as organophosphates and carbamates, which affect the nervous systems, while others may only irritate a person's eyes or skin, they may be cancer causing, or may affect hormones of the endocrine system.
Hazardous waste facilities
Recent studies show that hazardous waste facilities are more likely to be located in communities of color and low-income neighborhoods. In fact, communities with a high concentration of racial minorities are nine times more likely to be exposed to environmentally hazardous facilities than communities with a low concentration of minorities. A 2002 study in Massachusetts by sociologists Daniel R. Faber and Eric J. Krieg found racially-based biases in the placement of 17 industrial waste facilities. Residential segregation is correlated with higher cancer risk; as segregation increases, cancer incidence is higher. A 2018 study by the American Journal of Public Health found that Black people are exposed to 54% more particulate matter than the average American. In Los Angeles, minority children have the highest risk of being exposed to air pollution at school. Environmental health scientists Rachel Morello-Frosch and Manuel Pastor, Jr. found that "at schools ranked in the bottom fifth for air quality, the children were 92% minority." They also found that air pollution is associated with decreased achievement in school. The United States Environmental Protection Agency and United States Census Bureau found that, in the mid-Atlantic and Northeastern regions of the US, minorities are exposed to 66% more particulate matter from vehicles than white Americans. In a study in 2000 in Texas, sociologists Kingsley Ejiogu and Hon R. Tachia found that the percent Asians and percent Hispanics were significant predictors of toxic sites.
Environmental racism is very prevalent in many states across the country. Environmental racism raises ethical issues and can also have implications for a state's laws and constitution, for example the "Clean Air Act", "the Fourteenth Amendment" and the "Civil Rights Act".
An example of a case of environmental racism is a small mainly African American (90%) town called Uniontown, Alabama where a toxic landfill is believed to have caused serious health issues. In 2010, the Tennessee Valley Authority moved four million cubic yards of coal ash to a landfill in Uniontown without providing citizens any protection from the waste. Mental health issues, a one-in-five chance of developing cancer and reproductive issues were associated with mercury and arsenic contained within the ash.
Other examples include West Dallas, Texas where African American housing projects have been set up twenty paces from a battery recycling smelter, and Chester, Pennsylvania which has become an attraction for toxic waste sites. In California the government also decided to allow pollution in vulnerable communities. The effect of environmental racism is seen in the health data which shows that African Americans are three times more likely to die from asthma. Three out of five African Americans live in a community with a least one toxic waste site. On average it takes twenty percent longer for toxic sites in minority community towns to be placed on the national priority list than white areas.
Water pollution
A 2002 study published by the Annual Review of Public Health found that Low-income communities and communities of color are more likely to have contaminated drinking water. A 2019 study by a team of epidemiologists found that community water systems with higher nitrate concentrations tended to serve communities with higher proportions of Hispanic residents. Nitrates have been linked to cancer, reproductive problems, and death in infants. Additionally, contamination of drinking water contributes to 20 percent of lead poisoning in children; per studies in 2000 and 2004, low-income African American and Latino children have disproportionately high levels of lead in their blood.
Several case studies demonstrate race-based inequalities in access to clean water. A recent, highly publicized example of water pollution's disproportionate effect on racial minorities is the Flint water crisis. In 2014, Flint, Michigan, a city with a 57% Black population, switched its drinking water to the Flint River, which led to complaints about the water's taste and color. Studies found that the water was contaminated with lead from aging pipes. , the US government had spent $80 million in addressing the Flint Water Crisis.
Another example is East Orosi, a small, low-income, Latino town in California's San Joaquin Valley where the groundwater was found to be contaminated with nitrates due to fertilizer runoff at nearby farms.
Air pollution
Air pollution is a growing problem in populous cities, particularly those neighboring airports. In the U.S., 70% of airborne lead exposure is caused by leaded aviation fuel. The Biden administration has prioritized efforts to reduce child lead exposure throughout their administration, but they have not yet banned the use of leaded aviation fuel. While the Clean Air Act of 1963 served to ban the uses of leaded gasoline, it has yet to address the continued consumption of leaded aviation fuel. The negative impact of the use of leaded aviation fuel can be seen in the case of the Reid-Hillview Airport in San Jose, where in 2021 blood lead levels of children living within a 1.5 mile radius of the airport tested at double that of children at the peak of the Flint Michigan Water crisis. Furthermore, 97% of the affected community identifies as non-white. Since then, the use of such fuel has been banned in Santa Clara County, but it remains a primary contributor of airborne lead in the rest of the United States.
Health effects
Minority populations are exposed to greater environmental health risks than white people, according to the Environmental Protection Agency (EPA). The advocacy organisation Greenlining cites EPA assessments finding that Blacks are exposed to 1.5 times more air pollutants causing heart and lung disease than whites, while exposure rates for Hispanics were 1.2 times the amount for non-Hispanic whites. People in poverty had 1.3 times the exposure of those not in poverty.
Environmental pollution has been found to cause physical and mental disabilities, cancer, and asthma. Exposure to industrial chemicals have correlated with increased cancer rates, learning disabilities, and neurobehavioral disorders. Some industrial chemicals have been identified as endocrine disruptors, which means they interfere with the functioning of hormones. Endocrine disrupters have been linked to attention deficit hyperactivity disorder, Parkinson's disease, Alzheimer's disease, metabolic disorders, diabetes, cardiovascular disease, obesity, and infertility. There is a strong link between cancer and childhood exposure to pesticides, solvents, and other toxic substances.
Non-white populations, especially Black Americans, are exposed to a higher concentration of harmful chemicals than white populations. High-emissions in majority-Black areas may contribute to the high prevalence of conditions such as cardiovascular disease mortality and asthma in Black populations. Additionally, climate change has been found to increase the frequency of extreme heat and pollen events that exacerbate asthma, disproportionately affecting pediatric ED visits of BIPOC.
A row of industrial plants in Louisiana has now been dubbed "Cancer Alley" due to the high prevalence of cancer cases in the surrounding communities. This area is about 50% African-American, and has a 20.7% poverty rate. One study found that rates of stomach cancer, diabetes, and heart disease were significantly higher in Cancer Alley, and in Louisiana, than the United States overall.
Since the 1700s, power companies have dumped coal ash into pits and ponds, especially in the Southeast. Coal ash is mostly composed of lead, arsenic, selenium, and mercury. Each of these minerals individually are unsafe for the human body, but scientists are unsure of how harmful the components are combined. Mercury, for example, can damage reproductive health. Lead causes developmental disorders, arsenic can lead to rashes and lesions. Kristina Zierold, an environmental health scientist and epidemiologist, concluded that there are clusters of cancer around coal ash sites where workers are exposed. However, scientists have not been able to prove a direct link between coal ash and cancer. Measuring coal ash's impact on a control group would be dangerous and unethical, so researchers have had to extrapolate based on their current knowledge of toxins. Researchers have observed that the placement of a coal ash dump near a community causes dramatic increases in cancer rates and neurological issues among children.
Low-income households and people of color are often unable to afford adequate healthcare to treat pollution-related health problems. One study found that 34% of adults live without healthcare coverage in a primarily African-American, low-income neighborhood in Chicago. This results in the compounding of health issues within these communities, and exacerbates a cycle of poverty; sickness eats up money, often forcing families to sell assets to pay off medical debt and/or quit a job to take care of family members. It also results in less money to pass down to children or share with local organizations, such as schools.
A study involving 108 urban areas found that neighborhoods with a history of redlining were five to twelve degrees hotter than neighborhoods without redlining. This increase in temperature is caused by the urban heat island, an area which has a slightly warmer climate than the surrounding area. Low income communities are acutely at risk to heat mortality because of reduced access to air conditioning as well as tree cover. "Temperatures on a scorching summer day can vary as much as 20 degrees across different parts of the same city, with poor or minority neighborhoods often bearing the brunt of that heat".
Natural disasters
The immediate impact of a natural disaster does not discriminate, but responses do when the lingering results of structural racism hinder relief. Natural disasters have historically had a larger impact on poor African Americans than wealthy whites. Structural disinvestment in communities of color additionally reduces their ability to respond to climate disasters, for instance, Black survivors of natural disasters are less likely to receive FEMA assistance. In counties hit by natural disasters, the wealth of white residents increased while Black residents fell. In 2020, FEMA's advisory council admitted the historic unfairness in federal disaster response and asked the agency to address the issue.
In particular, Black people were disproportionately affected by Hurricane Katrina. Predominantly Black communities were more likely to be located in low-lying areas that were more vulnerable to flooding. Evacuation plans were insufficient for populations without access to a car. At the time, over a third of New Orleans' African-American residents did not have cars. The city also only had one-quarter the number of buses that would have been necessary to evacuate all car-less residents, and many buses were lost during the flooding. The disorganized response to the storm and flooding also disproportionately affected Black victims. Michael D. Brown, the head of the Federal Emergency Management Agency, was not aware of starving crowds at the New Orleans Convention Center until he heard about it on the news. Deliveries of supplies to the convention center did not arrive until four days after Katrina hit.
Another example is the 1928 Okeechobee hurricane, the first category 5 hurricane officially recorded in the Atlantic. The storm devastated much of the southern coast of Florida, but hit low-lying, Black migrant-worker communities particularly hard. In fact, over 75% of the 3000 recorded deaths were Black migrant workers. Most Black bodies were burned or buried in mass graves. The towns of Belle Glade, Pahokee, and South Bay were "virtually wiped off the map".
Natural disasters have also been used as an opportunity to oppress African Americans. For example, during the Great Mississippi Flood of 1927, whites were evacuated, while African Americans were placed into disaster-relief "concentration camps" and forced to work while being held at gunpoint.
Access to public green space
A study by sociologist Salvatore Saporito and Daniel Casey found that urban green space is generally distributed unequally across racial and economic groups. Low-income, people of color tend to live in areas with less vegetation than their white, wealthy counterparts. There is also a relationship between "city-level racial and economic segregation and differences in exposure to green space between the members of different racial and income groups." The more segregated a city is, the more likely it is that neighborhoods with large concentrations of racial minorities will have less green space than white neighborhoods.
According to Ian Leahy, "the wealthiest neighborhoods have 65% more tree canopy cover than the highest poverty neighborhoods." Tree canopy cover is the measure of the percentage of the ground covered by a vertical projection of the tree. Inequities in tree canopy cover and the presence of urban green space arise from policies such as redlining. Redlining is the "historical practice of refusing home loans or insurance to whole neighborhoods based on a racially motivated perception of safety for investment." This policy affected mainly Black and Latino individuals, thus shaping the current urban green spaces. Redlined areas have less green space, are on average 2.6 degrees Celsius warmer than neighboring areas, and experience other environmental hazards, leading to discussions of heath disparities.
There are few studies on the link between green spaces and health, but it is a rising concern with increasing urbanization and spatial planning policies of densification. There is one epidemiological study that was performed in the Netherlands that showed a positive link between abundant green spaces and better health mostly apparent among the elderly, housewives, and people from lower socioeconomic groups. Other small epidemiological studies show that green space is positively correlated with self perceived health, number of symptoms experienced, and mortality risk. The U.S. Department of Agriculture states that the relationship between urban green space and health is intrinsically related and recent studies show that immersion in natural landscapes can reduce stress and improve mental and social health. Research continues in underserved communities and the link of green space to health outcomes.
The presence of green space in one's living environment has been found to have an important impact on physical and mental health. Green space can contribute to stress reduction and attention restoration, as well as improved social cohesion and increased physical activity.
A proposal to develop a police training facility at the Old Atlanta Prison Farm in Atlanta, Georgia has resulted in community protest. Opponents to the project would like to conserve the area as part of the 3500 acre South River forest (a large green space in southeast Atlanta), and they have said that the development is an example of environmental racism that will lead to increased police brutality against people of color.
Native Americans
History
According to Potawatomi philosopher Kyle Powys Whyte and Lower Brule Sioux historian Nick Estes, the first "environmental apocalypse" is the coming of colonialism. Settlers used industrial military technologies to systematically kill Native Americans and force their removal. Then, they harnessed indigenous land for agriculture and industrial facilities. Settlers dramatically changed ecosystems through deforestation, overharvesting, and pollution. Additionally, academics Zoe Todd and Heather Davis propose that colonialism has played a major role in environmental degradation. The beginning of colonialism marked the beginning of the Anthropocene. When European settlers landed in the Americas in 1492, they set in motion the Columbian Exchange, drastically reshaping the biology and ecological landscape of the Americas. Simultaneously, there was a drop in carbon dioxide levels in the geologic layer following the genocide of indigenous people in the Americas and the regrowth of plants. Settler colonialism is marked by the process of "terraforming"—damming of rivers, clear-cutting of forests, and importation of plants and animals.
For instance, in colonial New England, settlers cleared forests and woodlands for farms and sent the cleared forest wood back to England to be used in soap and glass manufacturing. Settlers believed that deforestation would lead to warmer winters like those in England, which would attract more British colonists to the region and allow settlers to grow the crops they preferred. For example, according to U.S. Constitution signee Hugh Williamson, warming temperatures would create a more pleasurable environment, proving that the continent was better off because of, and in the hands of, white settlers. These early settlers also believed that deforestation would create an environment more hospitable to those with "fair skin" instead of "savages."
Throughout the nineteenth century, as the United States spread its territory from the Atlantic Ocean to the Pacific Ocean, Native Americans were pushed onto reservations, which were often lands that were deemed undesirable to white settlers because of poor soil quality. Additionally, they tended to be located next to tracts of federally owned land. During World War II, a significant number of military facilities were built or expanded onto these federal lands. The United States sought "remote lands to house bombing ranges and related noxious activities," and, thus, many facilities contained dangerous unexploded ordnance, putting Native populations at risk of exposure to toxic chemicals. In the early 1990s, the United States government attempted to blackmail Native populations by offering tribes millions of dollars for hosting nuclear waste facilities. This offer was appealing to many tribes because of extreme poverty on reservations.
Through the 1940s and 1950s, the US Military responded to wartime industry by erecting uranium mines in the southwestern deserts. The nearest residents were almost exclusively Native American tribal members. Navajo and Hopi drinking water supply in Nevada, Arizona, and New Mexico continues to this day to be affected by runoff and pollution from neighboring mines.
Hazardous waste on reservations
Because Native Americans live at the lowest socioeconomic level in the U.S., they are at the highest risk for toxic exposure. The risk is multiplied for indigenous people because they rely on land affected by the accumulation of toxic materials for food supplies. One significant environmental hazard on tribal land is the construction of government and commercial hazardous waste sitings. A survey of 25 Indian reservations revealed that there were 1200 hazardous waste activity sites on or near the selected reservations. According to a study by sociologists Gregory Hooks and Chad L. Smith, indigenous reservations are positively associated with extremely dangerous sites, far above the national average. Examples of hazardous sites include a nuclear power plant built on the edge of the Mdewakanton Sioux of Prairie Island reservation, cyanide heap-leach mining polluting water on the Fort Belknap Indian Reservation, and industrial waste dumps surrounding the St. Regis Mohawk Reservation. Furthermore, a disproportionate number of dangerous military facilities are located on or near Native land. Hooks' and Smith's study also found that the risk assessment code commonly used to measure the danger levels of a site may underestimate the damage it inflicts on Native American communities. Instead, the hazard probability model accounts for the fact that hazardous chemicals are in close proximity to public spaces, such as schools and hospitals.
Illegal dumping is another large environmental threat on tribal land. There are two categories of people who illegally dump on Native American reservations. Midnight dumpers are corporations and individuals that dump their waste on reservations without the permission of tribal governments. Native entrepreneurs are tribal members who contaminate Native land without tribal permission. Waste poses a severe health risk, leading to leukemia, organ ailments, asthma, and other conditions. Illegal pollution also results in a loss of tribal sovereignty by creating conditions in which intervention on the part of the United States federal government becomes necessary. The removal of toxic waste can be used as a "pretext to revert to past patterns of paternalism and control over Native American affairs on the reservation." For example, in the case of the Kaibab-Paitute tribe, the Waste Tech Corporation used the disposal of waste as an excuse to restrict tribal access to their own land and attempted to give themselves the unilateral right to determine where roads would be built.
Water quality
Native American communities are more likely to have contaminated drinking water. In 2006, 61% percent of drinking water systems on Native American reservations had health violations or other violations, compared to 27% of all public drinking water systems in the United States.
A highly publicized example of water pollution on a reservation is the Dakota Access Pipeline. The Dakota Access Pipeline transports oil from North Dakota to an oil terminal in Illinois. Although it does not cross directly on a reservation, the pipeline is under scrutiny because it passes under a section of the Missouri River which is the main drinking water source for the Standing Rock Sioux Tribe. Pipelines are known to break, with the Pipeline and Hazardous Materials Safety Administration (PHMSA) reporting more than 3,300 leak and rupture incidents for oil and gas pipelines since 2010. The pipeline also traverses a sacred burial ground for the Standing Rock Sioux Tribe. Kelly Morgan, the Standing Rock Sioux's tribal archeologist, has voiced concerns that the water crossings destroy land used for burials and other important historical and cultural information, including several stones and markers. These concerns were ignored. President Barack Obama revoked the permit for the project in December 2016 and ordered a study on rerouting the pipeline. President Donald Trump reversed this order and authorized the completion of the pipeline. The pipeline remains commercially operable. There are still ongoing litigation efforts by the Standing Rock Sioux Tribe opposing the Dakota Access Pipeline in an effort to shut it down permanently.
Additionally, in 2015, the Gold King Mine spill contaminated 3 million gallons of water in the Colorado River, which served as a primary source of drinking water for the Navajo and Hopi nations downstream. The Navajo and Hopi subsequently recorded dangerously high levels of arsenic and lead in their water supply. Through the following litigative proceedings, the US EPA appropriated just $156,000 in reparations to those affected by the Gold King Mine spill.
Declining riparian oxygen has also affected Washington's Quinault tribe which has reported greater levels of dead fish, affecting their seafood business.
Civil rights litigation
The environmental justice movement in the US was heavily influenced by the civil rights movement, and shares many of the same goals and tactics. Existing community organizations and leaders that contributed to mobilize the civil rights movement have also engaged in environmental justice work. Several prominent environmental justice lawsuits in the US have attempted to claim discrimination based on the Civil Rights Act of 1964, though none of these have so far been successful.
Litigation
Some environmental justice lawsuits have been based on civil rights laws. The first case to claim environmental discrimination in the siting of a waste facility under civil rights law was Bean v. Southwestern Waste Management, Inc. (1979). With the legal representation of Linda McKeever Bullard, residents of Houston's Northwood Manor opposed the decision of the city and Browning Ferris Industries to construct a solid waste facility near their mostly African-American neighborhood. Although the Northwood Manor residents lost the case, there were several lasting outcomes: the city of Houston later restricted the dumping of waste near public facilities such as schools; the strategy of using civil rights law in environmental justice cases was adopted in other cases, and Bullard's husband (Robert Bullard) became an increasingly visible scholar and writer on environmental justice.
The Equal Protection Clause of the Fourteenth Amendment has been used in many environmental justice cases. This strategy requires that the plaintiff prove discriminatory intent on the part of the defendant, which is very difficult and has never been done in an environmental justice case.
Title VI of the Civil Rights Act of 1964 has also been used in lawsuits that claim environmental inequality. The two most relevant sections in these cases are sections 601 and 602. section 601 prohibits discrimination based on race, color, or national origin by any government agency receiving federal funds. To win an environmental justice case that claims an agency violated this statute, the plaintiff must prove the agency intended to discriminate. Section 602 requires agencies to create rules and regulations that uphold section 601. This section is useful because the plaintiff must only prove that the rule or regulation in question had disparate impact. While disparate impact is much easier to demonstrate than discriminatory intent, cases brought under section 602 are not typically successful. It is also unclear whether citizens have right of action to sue under section 602. In Seif v. Chester Residents Concerned for Quality Living (1998), a district court determined that residents did not have right of action; but this decision was overturned in an appeal. When the case went to the supreme court, the case was dismissed as moot because the plaintiff had withdrawn their permit. Earlier decisions in the lower courts were vacated, leaving no judgment on the books establishing citizen right of action for section 602.
Successful environmental justice litigation has typically used environmental law or tort law. While cases brought under civil rights law may have political advantages, these cases are not typically successful in court.
Policy responses
Five cities, including Seattle, Portland, Baltimore, Chicago, and Oakland, have passed ordinances banning fossil fuel storage and infrastructure expansion.
Federal agencies
In the United States it was also found that income inequality greatly affected the quality of the environment in which people live. People of colour and the poor in America on average experience much lower quality environments than white people or the wealthy. Action was taken in the early 1990s by the American Government in an attempt to improve environmental quality for poorer regions. In 1992 the United States Environmental Protection Agency set up the Office of Environmental Equity, now known as the Office of Environmental Justice, to address the situation at hand. However the Office of Environmental Justice's work was undermined by Congress who refused to pass the bills which were presented to them by the EPA. Instead states began to pass their own bills which did very little to improve environmental quality for poorer areas. As a result, there has been little to no change in the ratios of environmental inequality whereas there has been a decline in the ratios of race and poverty.
Background
In 1994, President Clinton issued Executive Order 12898, "Federal Actions to Address Environmental Justice in Minority Populations and Low-Income Populations", which required environmental justice to be part of each federal agency's mission. Under Executive Order 12898 federal agencies must:
enforce all health and environmental statutes in areas with minority and low-income populations;
ensure public participation;
improve research and data collection relating to the health and environment of minority and low-income populations; and
identify differential patterns of consumption of natural resources among minority and low-income populations.
EO 12898 established an Interagency Working Group on Environmental Justice that is chaired by the EPA Administrator and heads of 17 departments, agencies, and several White House offices in order to collectively promote and advance environmental justice principles. This was a historical step in addressing environmental injustice on a policy level; however, the effectiveness of the Order is noted mainly in its influence on states as Congress never passed a bill making Clinton's Executive Order law. Many states began to require relevant agencies to develop strategies and programs that would identify and address environmental injustices being perpetrated at the state or local level.
In 2005, during President George W. Bush's administration, there was an attempt to remove the premise of racism from the Order. EPA's Administrator Stephen Johnson wanted to redefine the Order's purpose to shift from protecting low income and minority communities that may be disadvantaged by government policies to all people. Obama's appointment of Lisa Jackson as EPA Administrator and the issuance of Memorandum of Understanding on Environmental Justice and Executive Order 12898 established a recommitment to environmental justice. The fight against environmental racism faced some setbacks with the election of Trump. Under Trump's administration, there was a mandated decrease of EPA funding accompanied by a rollback on regulations which has left many underrepresented communities vulnerable.
Title VI of the Civil Rights Act of 1964 also forbids federal agencies from providing grants or funding opportunities to discriminatory programs.
U.S. Environmental Protection Agency
The Office of Environmental Justice (OEJ) was created in 1992 and has coordinated efforts of the EPA to meet environmental justice goals. The Office of Environmental Justice provides technical and financial assistance to communities working to address environmental justice issues. The National Environmental Justice Advisory Council (NEJAC) provides independent advice and recommendations to the EPA Administrator that crosses various environmental justice issues. The Tribal Consultation & Indigenous People's Engagement works with federally recognized tribes and other indigenous peoples to prioritize their environmental and public health issues.
Tools and direct support
OEJ provides financial resources for creating healthy, sustainable and equitable communities through the Environmental Justice Small Grants Program and the Collaborative Problem-Solving Cooperative Agreement Program. , more than $36 million of financial assistance has been given to nearly 1,500 community-based organizations.
The Technical Assistance Services for Communities program provides a way for communities to gain better understanding of the decision-making process as well as assist to understand the science, regulations, and policies that impact environmental issues and EPA actions.
The EPA website on environmental justice has various resources such as EJSCREEN, a mapping tool and screening tool, Guidance on Considering Environmental Justice During the Development of an Action, Technical Guidance for Assessing Environmental Justice in Regulatory Analysis, trainings and workshops, and the Legal Tools Development document.
Emergency Planning and Right to Know Act of 1986
After the Bhopal disaster, where a Union Carbide plant released forty tons of methyl isocyanate into the atmosphere in a village just south of Bhopal, India, the U.S. government passed the Emergency Planning and Right to Know Act of 1986. Introduced by Henry Waxman, the act required all corporations to report their toxic chemical pollution annually, which was then gathered into a report known as the Toxics Release Inventory (TRI).
Corporate Toxics Information Report
The Corporate Toxics Information Project (CTIP) provides information and analysis on corporate pollution and its consequences for communities. The project develops corporate rankings, regional reports, industry reports based on industrial sectors, and presents this data in a web-based resource open to the public. The data is collected by the EPA and then analyzed and disseminated by the PERI institute.
Since 2004, the CTIP has also published an index of the top 100 corporate air polluters in the United States. The list is based on the EPA's Risk Screening Environmental Indicators (RSEI), which "assesses the chronic human health risk from industrial toxic releases", as well as the TRI. The Toxic 100 has been updated five times, with the latest update in 2016.
U.S. Department of Agriculture
The US Department of Agriculture (USDA) is the executive agency responsible for federal policy on food, agriculture, natural resources, and quality of life in rural America. The USDA has more than 100,000 employees and delivers over $96.5 billion in public services to programs worldwide. In its 2012 environmental justice strategy, the USDA stated a desire to integrate environmental justice into its core mission and operations. USDA does fund programs with social and environmental equity goals; however, it has no staff dedicated solely to EJ.
2012 Environmental Justice Strategy
On February 7, 2012, the USDA released a new Environmental Justice Strategic Plan identifying goals and performance measures beyond what USDA identified in a 1995 EJ strategy that was adopted in response to E.O. 12898. Generally, USDA believes its existing technical and financial assistance programs provide solutions to environmental inequity, such as its initiatives on education, food deserts, and economic development in impacted communities.
Initiatives in marginalized communities
Tribal outreach
The US EPA holds annual conferences, such as the Tribal Leaders Environmental Forum (TLEF), with Native American tribal leaders; EPA employees and tribal representatives meet in issue-based listening sessions and exchange environmental policy suggestions. The USDA has had a role in implementing Michelle Obama's Let's Move campaign in tribal areas by increasing Bureau of Indian Education schools' participation in federal nutrition programs: they develop community gardens on tribal lands, build tribal food policy councils, and provide Rural Development funding for community infrastructure in Indian Country. The U.S. Forest Service (USFS) is working to update its policy on protection and management of Native American Sacred Sites, an effort that has included listening sessions and government-to-government consultation. The Animal and Plant Health Inspection Service (APHIS) has also consulted with Tribes regarding management of reintroduced species where tribes may have a history of subsistence-level hunting of those species. Meanwhile, the Agricultural Marketing Service (AMS) is exploring a program to use meat from bisons raised on tribal land to supply AMS food distribution programs to tribes. The Intertribal Technical Assistance Network works to improve access of tribal governments, communities and individuals to USDA technical assistance programs. Federally recognized tribes are also eligible to apply for "Treatment as State" (TAS) status with the EPA, which gives the tribe jurisdictional authority to enforce their own environmental programs, regulations, and quality standards over nearby polluters or over the state in which they reside.
Technical and financial assistance
The NRCS Strike Force Initiative has identified impoverished counties in Mississippi, Georgia and Arkansas to receive increased outreach and training regarding USDA assistance programs. USDA credits this increased outreach with generating a 196 percent increase in contracts, representing more than 250,000 acres of farmland, in its Environmental Quality Incentives Program. In 2001, NRCS funded and published a study, "Environmental Justice: Perceptions of Issues, Awareness and Assistance," focused on rural, Southern "Black Belt" counties and analyzing how the NRCS workforce could more effectively integrate environmental justice into impacted communities.
The Farm Services Agency in 2011 devoted $100,000 of its Socially Disadvantaged Farmers and Ranchers program budget to improving its outreach to counties with persistent poverty. USDA's Risk Management Agency has initiated education and outreach to low-income farmers regarding use of biological controls, rather than pesticides, for pest control. The Rural Utilities Service administers water and wastewater loans, including SEARCH Grants that are targeted to financially distressed, small rural communities and other opportunities specifically for Alaskan Native villages.
Mapping
USFS has established several Urban Field Stations, to research urban natural resources' structure, function, stewardship, and benefits. By mapping urban tree coverage, the agency hopes to identify and prioritize EJ communities for urban forest projects.
Another initiative highlighted by the agency is the Food and Nutrition Service and Economic Research Service's Food Desert Locator. The Locator provides a spatial view of food deserts, defined as a low-income census tract where a substantial number or share of residents has low access to a supermarket or large grocery store. The mapped deserts can be used to direct agency resources to increase access to fresh fruits and vegetables and other food assistance programs.
The US EPA database EJ Screen is publicly available. EJ Screen maps the United States with socioeconomically determinant factors including income level and race, as well as environmental health data including rates of asthma and cancer occurrence in a given area. Where there is high correlation between socioeconomic determinants and detrimental health impacts, "EJ communities" are noted.
Activism
Concentrations of ethnic or racial minorities may also foster solidarity, lending support in spite of challenges and providing the concentration of social capital necessary for grassroots activism. Citizens who are tired of being subjected to the dangers of pollution in their communities have been confronting the power structures through organized protest, legal actions, marches, civil disobedience, and other activities.
Racial minorities are often excluded from politics and urban planning (such as sea level rise adaptation planning) so various perspectives of an issue are not included in policy making that may affect these excluded groups in the future. In general, political participation in African American communities is correlated with the reduction of health risks and mortality. Other strategies in battling against large companies include public hearings, the elections of supporters to state and local offices, meetings with company representatives, and other efforts to bring about public awareness and accountability.
In addressing this global issue, activists take to various social media platforms to both raise awareness and call to action. The mobilization and communication between the intersectional grassroots movements where race and environmental imbalance meet has proven to be effective. The movement gained traction with the help of Twitter, Facebook, Instagram, and Snapchat among other platforms. Celebrities such as Shailene Woodley, who advocated against the Keystone XL Pipeline, have shared their experiences including that of being arrested for protesting. Social media has allowed for a facilitated conversation between peers and the rest of the world when it comes to social justice issues not only online but in face-to-face interactions correspondingly.
Before the 1970s, communities of color recognized the reality of environmental racism and organized against it. For example, the Black Panther Party organized survival programs that confronted the inequitable distribution of trash in predominantly black neighborhoods. Similarly, the Young Lords, a Puerto Rican revolutionary nationalist organization based in Chicago and New York City, protested pollution and toxic refuse present in their community via the Garbage Offensive program. These and other organizations also worked to confront the unequal distribution of open spaces, toxic lead paint, and healthy food options. They also offered health programs to those affected by preventable, environmentally induced diseases such as tuberculosis. In this way, these organizations serve as precursors to more pointed movements against environmental racism.
Latino ranch laborers composed by Cesar Chavez battled for working environment rights, including insurance from harmful pesticides in the homestead fields of California's San Joaquin Valley. In 1967, African-American understudies rioted in the streets of Houston to battle a city trash dump in their locale that had killed two children. In 1968, occupants of West Harlem, in New York City, battled unsuccessfully against the siting of a sewage treatment plant in their neighborhood.
Efforts of activism have also been heavily influenced by women and the injustices they face from environmental racism. Women of different races, ethnicities, economic status, age, and gender are disproportionately affected by issues of environmental injustice. Additionally, the efforts made by women have historically been overlooked or challenged by efforts made by men, as the problems women face have been often avoided or ignored. Winona LaDuke is one of many female activists working on environmental issues, in which she fights against injustices faced by indigenous communities. LaDuke inducted into the National Women's Hall of Fame in 2007 for her continuous leadership towards justice.
Fighting against industrial facilities that were adding to the air, water and soil pollution caused by a nearby smelter that had operated for more than a century in Denver, Colorado, environmental and social justice activist Lorraine Granado and other residents of that city's Elyria-Swansea and Globeville neighborhoods formed Neighbors for a Toxic-Free Community. In 1991, they prevented the city from erecting a medical waste incinerator in their neighborhood. Three years later, they were involved in a successful class-action lawsuit that forced executives of ASARCO to clean up the pollution caused by the company's smelting plant. ASARCO subsequently paid $38 million to clean up arsenic, trioxide, cadmium, lead and other soil pollutants in Globeville and also paid $24 million in compensation to residents for decreased property values caused by the plant's pollution.
Art
Allison Janae Hamilton is an artist who focuses her work on examining the social and political ideas and uses of land and space, particularly in the Southern United States. Her work looks at who is affected by a changing climate, as well as the unique vulnerability that certain populations have. Her work relies on videos and photographs to show who is affected by global warming, and how their different lived experiences lend different perspectives to climate issues.
Energy
While alternative energies such as nuclear power and hydroelectric power are viewed as low-cost alternatives to traditional power like coal and oil and gas, each presents its own environmental justice issues.
Nuclear power
Nuclear power has affected Native American peoples primarily through uranium mining and nuclear waste storage on Native American lands. According to Ojibwe activist Winona LaDuke, "over 1,000 abandoned uranium mines lie on the Navajo reservation, largely untouched by any attempts to cover or cap or even landscape the toxic wastes."
According to academic Traci Brynne Voyles, "Rates of lung cancer and respiratory disease have skyrocketed for the Diné, a population described as recently as the 1950s by public health experts as being 'immune' to lung cancer. By the mid-1980s, researchers found astronomical rates of cancer deaths among former uranium miners." Further, "Radiation-related diseases are now endemic to many parts of the Navajo Nation, claiming the health and lives of former miners to be sure but also those of Navajos who would never see the inside of a mine. Diné children have a rate of testicular and ovarian cancer fifteen times the national average, and a fatal neurological disease called Navajo neuropathy has been closely linked to ingesting uranium-contaminated water during pregnancy."
In addition to abandoned mines on Navajo land, Skull Valley Goshute, Western Shoshone, and Ojibwe reservations also hold mines and are areas utilized for waste dumping and storage. Dakota people living next to the Prairie Island nuclear facility, too, have been exposed to "six times greater risk of cancer" due to radiation leaks.
Hydroelectric power
Hydroelectric dams in Oregon and California have killed salmon runs and flooded Native American sacred sites. Specifically, dams on the Klamath River are known for "squelching salmon runs" according to sociologist Kari Norgaard and Karuk biologist Ron Reed. Destruction of salmon runs then has negative effects on Karuk cultural and societal structures, such as breakdown of gender identity and gender roles within communities. Further, such ecological destruction contributes to food scarcity. So much that, according to The Washington Post, "The dams are quite literally killing Indians".
These hydroelectric dams can also cause methane to be released when the vegetation is flooded. This pollution can contaminate the water sources and the animals that live in the water, potentially harming those who drink this water and eat the fish from the contaminated water source.
Coal
Coal mining has harmed low-income rural communities in the Appalachian Mountain area. Coal mining in the region involves blasting apart mountaintops, and excess rocks are dumped into valleys and streams. Sociologist Shannon Elizabeth Bell explains that "Communities in proximity to mountaintop removal mining and other industry related activities suffer numerous problems as a result of these coal operations, including flooding, respiratory disorders from coal dust, well water contamination, and technological disasters resulting from breaches or failures in impoundments containing coal waste from coal cleaning or coal-burning plants." Further, "Many residents argue that they are forced to suffer these environmental injustices because Central Appalachia is serving as an 'energy sacrifice zone' for the rest of the nation."
These activities have been shown to contaminate surrounding communities' air and water with lead, mercury, and arsenic. Such contamination has led to health issues such as hyperactivity and aggression in children, high blood pressure, kidney failure, cardiovascular diseases, premature delivery or miscarriages in pregnancy, negative effects on liver, kidney, and cardiac tissues, neurological diseases, brain damage in newborns, respiratory diseases, anemia and leukopenia, skin and lung cancer, coma, and gene mutations in surrounding communities.
In addition to effects on communities within coal extraction zones, coal burning facilities have been historically placed in low-income, inner city neighborhoods that have majority Latinx and black populations. Further, proposed coal export projects in or adjacent to Native American communities, such as the Gateway Pacific Terminal next to ancestral village sites of the Lummi Nation of Northwest Washington, would "increase congestion and toxic runoff in the Salish Sea, ... endangering salmon and orcas," which are species that have important relationships with the Lummi people.
Oil and gas
New gas and oil pipelines have been proposed to be built around the United States. A previously proposed project would have constructed an Alaskan natural gas pipeline to deliver natural gas to the lower continental 48 states. The areas in which this oil and gas drilling would occur in Northern Alaska are inhabited mainly by Native Americans.
Fracking sites can release toxins, particularly methane, that pollute the air and contaminate water.
Case studies
The Bronx, in New York City, has become a recent example of Environmental Justice succeeding. Majora Carter spearheaded the South Bronx Greenway Project, bringing local economic development, local urban heat island mitigation, positive social influences, access to public open space, and aesthetically stimulating environments. The New York City Department of Design and Construction has recently recognized the value of the South Bronx Greenway design, and consequently utilized it as a widely distributed smart growth template. This venture is the ideal shovel-ready project with over $50 million in funding.
Industry in the city of Chicago, Illinois, has impacted minority populations, especially the African American community. Several coal plants in the region have been implicated in the poor health of their local communities, a correlation exacerbated by the fact that 34% of adults in those communities do not have health care coverage.
Cancer-causing PCBs were dumped into a creek in Cheraw, South Carolina, by Burlington Industries until the 1970s. In 2018, five families had to leave their homes after Hurricane Florence hit the area and caused the chemicals' remains to wash up near the houses. Local researchers also detected the toxic waste from the PCBs in the soil of a local playground.
People living in Pahokee, Florida, face a thick level of soot that pollutes the local area each October due to sugar burning. The sugarcane farmers set their fields on fire before each harvest to burn everything down but the sugarcane. The pollution that results then travels and negatively affects the surrounding largely poor, Black communities. A 2015 study supported by the United States Department of Education determined that those exposed to this sugar field burning pollution face higher rates of respiratory issues and weakened immune systems.
See also
Pollution in the United States
Racism in the United States
Poverty
Health equity
Race and health in the United States
Social determinants of health in poverty
Climate change and poverty
Health inequality and environmental influence
Intergenerational equity
Environmental policy of the United States
Environmental history of the United States
References
Environmental controversies
Urban decay in the United States
Environmental social science concepts
Environment and society
Racism in the United States | Environmental racism in the United States | [
"Environmental_science"
] | 10,494 | [
"Environmental social science concepts",
"Environmental social science"
] |
69,133,408 | https://en.wikipedia.org/wiki/Microswimmer | A microswimmer is a microscopic object with the ability to move in a fluid environment. Natural microswimmers are found everywhere in the natural world as biological microorganisms, such as bacteria, archaea, protists, sperm and microanimals. Since the turn of the millennium there has been increasing interest in manufacturing synthetic and biohybrid microswimmers. Although only two decades have passed since their emergence, they have already shown promise for various biomedical and environmental applications.
Given the recent nature of the field, there is yet no consensus in the literature for the nomenclature of the microscopic objects this article refers to as "microswimmers". Among the many alternative names such objects are given in the literature, microswimmers, microscale swimmers, micro/nanorobots and micro/nanomotors are likely the most frequently encountered. Other common terms may be more descriptive, including information about the object shape, e.g., microtube or microhelix, its components, e.g., biohybrid, spermbot, bacteriabot, or micro-bio-robot, or behavior, e.g., microrocket, microbullet, microtool or microroller. Researchers have also named their specific microswimmers e.g., medibots, hairbots, iMushbots, IRONSperm, teabots, biobots, T-budbots, or MOFBOTS.
Background
In 1828, the British biologist Robert Brown discovered the incessant jiggling motion of pollen in water and described his finding in his article "A Brief Account of Microscopical Observations…", leading to extended scientific discussion about the origin of this motion. This enigma was resolved only in 1905, when Albert Einstein published his celebrated essay Über die von der molekularkinetischen Theorie der Wärme geforderte Bewegung von in ruhenden Flüssigkeiten suspendierten Teilchen. Einstein not only deduced the diffusion of suspended particles in quiescent liquids, but also suggested these findings could be used to determine particle size — in a sense, he was the world's first microrheologist.
Ever since Newton established his equations of motion, the mystery of motion on the microscale has emerged frequently in scientific history, as famously demonstrated by a couple of articles that should be discussed briefly. First, an essential concept, popularized by Osborne Reynolds, is that the relative importance of inertia and viscosity for the motion of a fluid depends on certain details of the system under consideration. The Reynolds number , named in his honor, quantifies this comparison as a dimensionless ratio of characteristic inertial and viscous forces:
Here, represents the density of the fluid; is a characteristic velocity of the system (for instance, the velocity of a swimming particle); is a characteristic length scale (e.g., the swimmer size); and is the viscosity of the fluid. Taking the suspending fluid to be water, and using experimentally observed values for , one can determine that inertia is important for macroscopic swimmers like fish ( = 100), while viscosity dominates the motion of microscale swimmers like bacteria ( = 10−4).
The overwhelming importance of viscosity for swimming at the micrometer scale has profound implications for swimming strategy. This has been discussed memorably by E. M. Purcell, who invited the reader into the world of microorganisms and theoretically studied the conditions of their motion. In the first place, propulsion strategies of large scale swimmers often involve imparting momentum to the surrounding fluid in periodic discrete events, such as vortex shedding, and coasting between these events through inertia. This cannot be effective for microscale swimmers like bacteria: due to the large viscous damping, the inertial coasting time of a micron-sized object is on the order of 1 μs. The coasting distance of a microorganism moving at a typical speed is about 0.1 angstroms (Å). Purcell concluded that only forces that are exerted in the present moment on a microscale body contribute to its propulsion, so a constant energy conversion method is essential.
Microorganisms have optimized their metabolism for continuous energy production, while purely artificial microswimmers (microrobots) must obtain energy from the environment, since their on-board-storage-capacity is very limited. As a further consequence of the continuous dissipation of energy, biological and artificial microswimmers do not obey the laws of equilibrium statistical physics, and need to be described by non-equilibrium dynamics. Mathematically, Purcell explored the implications of low Reynolds number by taking the Navier-Stokes equation and eliminating the inertial terms:
where is the velocity of the fluid and is the gradient of the pressure. As Purcell noted, the resulting equation — the Stokes equation — contains no explicit time dependence. This has some important consequences for how a suspended body (e.g., a bacterium) can swim through periodic mechanical motions or deformations (e.g., of a flagellum). First, the rate of motion is practically irrelevant for the motion of the microswimmer and of the surrounding fluid: changing the rate of motion will change the scale of the velocities of the fluid and of the microswimmer, but it will not change the pattern of fluid flow. Secondly, reversing the direction of mechanical motion will simply reverse all velocities in the system. These properties of the Stokes equation severely restrict the range of feasible swimming strategies.
As a concrete illustration, consider a mathematical scallop that consists of two rigid pieces connected by a hinge. Can the "scallop" swim by periodically opening and closing the hinge? No: regardless of how the cycle of opening and closing depends on time, the scallop will always return to its starting point at the end of the cycle. Here originated the striking quote: "Fast or slow, it exactly retraces its trajectory and it's back where it started". In light of this scallop theorem, Purcell developed approaches concerning how artificial motion at the micro scale can be generated. This paper continues to inspire ongoing scientific discussion; for example, recent work by the Fischer group from the Max Planck Institute for Intelligent Systems experimentally confirmed that the scallop principle is only valid for Newtonian fluids.
Physics
As discussed in the previous section, the motion of microswimmers is controlled by viscosity, meaning the motion is drag-dominant. In addition, the scallop theorem demonstrates microswimmers are unable to rely on time-dependence for movement, requiring them to have more than one degree of freedom. Derivations for the parallel and normal components of drag on simple geometries in creeping flow can be found in literature, and recorded media, notably in spheres:
and spheroids with major and minor axis a, b:
Due to the linear nature of the governing fluid equations, the superposition principle may be used to model more complex geometries, such as corkscrews, following the analysis of Purcell and others. For example, the drag and torque on the helical coil is as follows:
Where . It is important to note that while the scallop theorem requires more than one degree of freedom, external forcing (e.g., magnetic) allows for the motion of a simple corkscrew.
Types
Different types of microswimmers are powered and actuated in different ways. Swimming strategies for individual microswimmers as well as swarms of microswimmers have been examined down through the years. Typically, microswimmers rely either on external power sources, as it is the case for magnetic, optic, or acoustic control, or employ the fuel available in their surroundings, as is the case with biohybrid or catalytic microswimmers. Magnetic and acoustic actuation are typically compatible with in vivo microswimmer manipulation and catalytic microswimmers can be specifically engineered to employ in vivo fuels. The use of optical forces in biological fluids or in vivo is more challenging, but interesting examples have nevertheless been demonstrated.
Often, researchers choose to take inspiration from nature, either for the entire microswimmer design, or for achieving a desired propulsion type. For example, one of the first bioinspired microswimmers consisted of human red blood cells modified with a flagellum-like artificial component made of filaments of magnetic particles bonded via biotin–streptavidin interactions. More recently, biomimetic swimming inspired by worm-like travelling wave features, shrimp locomotion, and bacterial run-and-tumble motion, was demonstrated by using shaped light.
A different nature-inspired approach is the use of biohybrid microswimmers. These comprise a living component and a synthetic one. Biohybrids most often take advantage of the microscale motion of various biological systems and can also make use of other behaviours characterising the living component. For magnetic bioinspired and biohybrid microswimmers, typical model organisms are bacteria, sperm cells and magnetotactic cells. In addition to the use of magnetic forces, actuation of bioinspired microswimmers was also demonstrated using e.g., acoustic excitation or optical forces. Another nature-inspired behavior related to optical forces is that of phototaxis, which can be exploited by e.g., cargo-carrying microorganisms, synthetic microswimmers or biohybrid microswimmers. A number of recent review papers are focused on explaining or comparing existing propulsion and control strategies used in microswimmer actuation. Magnetic actuation is most often included for controlled in vivo guiding, even for microswimmers which rely on a different type of propulsion. In 2020, Koleoso et al. reviewed the use of magnetic small scale robots for biomedical applications and provide details about the various magnetic fields and actuation systems developed for such purposes.
Strategies for the fabrication of microswimmers include two-photon polymerisation 3D printing, photolithography, template-assisted electrodeposition, or bonding of a living component to an inanimate one by exploiting different strategies. More recent approaches exploit 4D printing, which is the 3D printing of stimuli-responsive materials. Further functionalization is often required, either to enable a certain type of actuation, e.g., metal coating for magnetic control or thermoplasmonic responses, or as part of the application, if certain characteristics are required for e.g., sensing, cargo transport, controlled interactions with the environment, or biodegradation.
Microswimmers can also be categorized by their propulsion methods, and two primary methods are used: self-propulsion and external-field propulsion. In self-propulsion, a chemical fuel is coated over the robot that reacts with the liquid environment to create bubbles that propel the robot. External-field propulsion offers more variety, using optical, magnetic, acoustic, or electric fields. External field is better suited for biological applications as it will not need chemical fuels that produce pollutants that may be harmful to the host that the microswimmers are servicing including films and chemicals that may be biocompatible. This propulsive method also provides higher spatial resolution and more controllability, with recent advancements enabling three-dimensional movement enhancing the flexibility and functionality of microswimmers.
Natural microswimmers
Motile systems have developed in the natural world over time and length scales spanning several orders of magnitude, and have evolved anatomically and physiologically to attain optimal strategies for self-propulsion and overcome the implications of high viscosity forces and Brownian motion, as shown in the diagram on the right.
Some of the smallest known natural motile systems are motor proteins, i.e., proteins and protein complexes present in cells that carry out a variety of physiological functions by transducing chemical energy into mechanical energy. These motor proteins are classified as myosins, kinesins, or dyneins. Myosin motors are responsible for muscle contractions and the transport of cargousing actin filaments as tracks. Dynein motors and kinesin motors, on the other hand, use microtubules to transport vesicles across the cell. The mechanism these protein motors use to convert chemical energy into movement depends on ATP hydrolysis, which leads to a conformation modification in the globular motor domain, leading to directed motion.
Apart from motor proteins, enzymes, traditionally recognized for their catalytic functions in biochemical processes, can function as nanoscale machines that convert chemical energy into mechanical action at the molecular dimension. Diffusion of various enzymes (e.g. urease, and catalase), measured by fluorescent correlated spectroscopy (FCS), increases in a substrate-dependent manner. Moreover, when enzymes are membrane-bound, their catalytic actions can drive lipid vesicle movement. For instance, lipid vesicles integrated with enzymes such as transmembrane adenosine 5’-triphosphatase, membrane-bound acid phosphatase, or urease exhibit enhanced mobility correlating with the enzymatic turnover rate.
Bacteria can be roughly divided into two fundamentally different groups, gram-positive and gram-negative bacteria, distinguished by the architecture of their cell envelope. In each case the cell envelope is a complex multi-layered structure that protects the cell from its environment. In gram-positive bacteria, the cytoplasmic membrane is only surrounded by a thick cell wall of peptidoglycan. By contrast, the envelope of gram-negative bacteria is more complex and consists (from inside to outside) of the cytoplasmic membrane, a thin layer of peptidoglycan, and an additional outer membrane, also called the lipopolysaccharide layer. Other bacterial cell surface structures range from disorganised slime layers to highly structured capsules. These are made from secreted slimy or sticky polysaccharides or proteins that provide protection for the cells and are in direct contact with the environment. They have other functions, including attachment to solid surfaces. Additionally, protein appendages can be present on the surface: fimbriae and pili can have different lengths and diameters and their functions include adhesion and twitching motility.
Specifically, for microorganisms that live in aqueous environments, locomotion refers to swimming, and hence the world is full of different classes of swimming microorganisms, such as bacteria, spermatozoa, protozoa, and algae. Bacteria move due to rotation of hair-like filaments called flagella, which are anchored to a protein motor complex on the bacteria cell wall.
The following table, based on Schwarz et al., 2017, lists some examples of natural or biological microswimmers.
Synthetic microswimmers
One of the current engineering challenges is to create miniaturized functional vehicles that can carry out complex tasks at a small scale that would be otherwise impractical, inefficient, or outright impossible by conventional means. These vehicles are termed nano/micromotors or nano/microrobots, and should be distinguished from even smaller molecular machines for energy, computing, or other applications on the one side and static microelectromechanical systems (MEMS) on the other side of this size scale. Rather than being electronic devices on a chip, micromotors are able to move freely through a liquid medium while being steered or directed externally or by intrinsic design, which can be achieved by various mechanisms, most importantly catalytic reactions, magnetic fields, or ultrasonic waves.
There are a variety of sensing, actuating, or pickup-and-delivery applications that scientists are currently aiming for, with local drug targeting for cancer treatment being one of the more prominent examples. For applications like this, a micromotor needs to be able to move, i.e., to swim, freely in three dimensions efficiently controlled and directed with a reliable mechanism.
It is a direct consequence of the small size scale of microswimmers that they have a low Reynolds number. This means the physics of how microswimmers swim is dominated by viscous drag forces, a problem which has been discussed extensively by physicists in the field. This kind of swimming has challenged engineers as it is not commonly experienced in everyday life, but can nonetheless be observed in nature for motile microorganisms like sperm or certain bacteria. Naturally, these microorganisms served as inspiration from the very beginning to create artificial micromotors, as they were able to tackle the challenges that an active, self-sufficient microswimmer vehicle has to face. With biomimetic approaches, researchers were able to imitate the flagella-based motion strategy of sperm and Escherichia coli bacteria by reproducing their respective flagellum shape and actuating it with magnetic fields.
Synthetic microswimmers are designed in a wide variety of shapes depending on the applications that they are used for. Similar to natural microswimmers there is an energy cost associated with the movement and control of a microswimmer. In nature, it is observed that micron-sized bacteria expend very little energy while larger microorganisms expend more energy. This principle can be translated to synthetic microswimmers where the connection between the sizing and shape of a microswimmer and the energy spent has been studied by researchers. Piro et al. argue that needle-like microswimmers are more energy efficient than other shapes, while disk-like microswimmers are carried by flow gradients in the liquid and will be naturally predisposed to follow a time-optimal trajectory. Helical microswimmers have also gained interest as a geometrical shape for microswimmers due to being bioinspired by microstructures within many different types of plants that serve as water vessels.
At the microscale, surface wettability is an important consideration in the material selection due to affecting the locomotion of the microswimmer. Hydrophobic surfaces produce a large contact angle with the liquid which has the effect of exerting less frictional drag torque on the microswimmer body resulting in a lower step-out frequency required for movement.
Microorganisms have adapted their locomotion to the harsh environment of low Reynolds number regime by invoking different swimming strategy. For example, the E. coli moves by rotating its helical flagellum, Chlamydomonas flagella have a breaststroke kind of motion. African trypanosome has a helical flagellum attached to the cell body with a planar wave passing through it. Swimming of these kind of natural swimmers have been investigated for the last half-century. As a result of these studies, artificial swimmers have also been proposed, like Taylor sheet, Purcell's two-hinge swimmer, three-linked spheres swimmer, elastic two-sphere swimmer and three-sphere with a passive elastic arm, which have further enhanced understanding about low Reynolds number swimmers. One of the challenges in proposing an artificial swimmer lies in the fact that the proposed movement stroke should not be reciprocal otherwise it cannot propel itself due to the Scallop theorem. In Scallop theorem, Purcell had argued that a swimmer with one-hinge or one degree of freedom is bound to perform reciprocal motion and thus will not be able to swim in the Stokes regime.
Purcell proposed two possible ways to elude from Scallop theorem, one is 'corkscrew' motion and the other is 'flexible oar' motion. Using the concept of flexible oar, Dreyfus et al reported a micro swimmer that exploit elastic property of a slender filament made up of paramagnetic beads. To break the time inversion symmetry, a passive head was attached to the flexible arm. The passive head reduces the velocity of the flexible swimmer, bigger the head, higher is the drag force experienced by the swimmer. The head is essential for swimming because without it the tail performs a reciprocal motion and the velocity of the swimmer reduces to zero.
In a study by Huang et al. microswimmers were placed in a sucrose solution to represent a viscosity that is similar to blood and tested different microswimmers and their ability to propel within the fluid using variants of the corkscrew and flexible oar techniques at different angles of alignment with an external magnetic field. Due to the misalignment a helical motion was produced for the flexible oar and corkscrew case. Under this test, the propulsion method that performed the fastest was the microswimmer with the tubular body and flexible planar tail due to taking advantage of the helical and corkscrew motion generated at an angle of 30-degree misalignment from the external magnetic field. Microswimmers relying on the corkscrew motion had a reduced speed due to an increase in the drag experienced by the microswimmer due to the wobbling motion on the body. However, when the microswimmer’s body is perpendicular to the external magnetic field the mobility of the flexible oar microswimmer was reduced due to a lack of the body’s helical motion while the wobbling effect on the corkscrew microswimmer was reduced so it was able to achieve better motion.
The corkscrew and flexible oar motion of a synthetic microswimmer can be largely affected by the viscosity of the fluid. An increase in viscosity decreases the motion of the microswimmer using either method, however, the decrease in movement at higher viscosity is larger for microswimmers using the flexible oar propulsion system. This is due to the reduction in helical motion of the body of the microswimmer causing an increase in the drag experienced by the body. Another effect experienced is a reduction in the bending of the tail which reduces the microswimmer’s ability to overcome the time-reversal symmetry.
Another way microswimmers can propel is through catalytic reactions. Taking inspiration from Whitesides, who used the decomposition of hydrogen peroxide (H2O2) to propel cm/mm-scale objects on a water surface, Sen et al. (2004) fabricated catalytic motors in the micrometer range. These microswimmers were rod-shaped particles 370 nm in diameter and consisted of 1 μm long Pt and Au segments. They propelled via the decomposition of hydrogen peroxide in solution which would be catalyzed into water and oxygen. The Pt/Au rods were able to consistently reach speeds of up to 8 μm/s in a solution of 3.3% hydrogen peroxide. The decomposition of hydrogen peroxide in the Pt side produces oxygen, two protons and two electrons. The two protons and electrons will travel towards the Au, where they will be used to react with another hydrogen peroxide molecule, to produce two water molecules. The movements of the two protons and the two electrons through the rod drag the fluid towards the Au side, thus this fluid flow will propel the rod in the opposite direction. This self-electrophoresis mechanism is what powers the motion of these rods. Further analysis of the Pt/Au rods showed that they were capable of performing chemotaxis towards higher hydrogen peroxide concentrations, transport cargo, and exhibited steerable motion in an external magnetic field when inner Ni segments were added.
Interest has been shown in using high-frequency sound waves for microswimmer navigation due to being cleared as safe for clinical studies by the U.S. Food and Drug Administration which would allow them to be used in biomedical applications. The microswimmer is designed to have a hydrophobic surface from being manufactured with a resin and small cavities which produce an air bubble when immersed in a liquid. When the high-frequency sound waves are applied to the microswimmer the bubble produces oscillations and generates enough movement to propel the microswimmer in a controlled direction.
An additional method that microswimmers can travel is through a response to a difference in temperature. Huang et al. designed a microswimmer to study the control of the shape of a 3D microswimmer. The microswimmer contains a rigid, non-expandable poly (ethylene glycol) diacrylate (PEGDA) combined with an N-isopropylacrylamide (NIPAAm) hydrogel layer that is thermally responsive. Within the hydrogel layer, there are magnetic nanoparticles that can control the folding axes. Through the alignment of the magnetic particles along the folding axes, the change in temperature can cause an active control of the microswimmer shape to propel in a fluid. Another example of thermal-based control is through the use of a pNIPAM-AAc hydrogel embedded with iron oxide which can be controlled through a magnetic field. Through the combination of magnetic fields and temperature-responsive materials, a dynamic control can be achieved.
Movement without external forces has been demonstrated for microswimmers. Bioinspired by microvelia beetles which are capable of gliding on the water at high speeds, microswimmers are proposed to take advantage of the Marangoni effect which is the mass transfer across a gradient of the surface tension for a fluid. Choi et al. demonstrated that photopatterned microswimmers without any mechanical actuation system or external force are capable of traversing a fluid through a polyvinyl alcohol (PVA) fuel source which causes the surface tension of the water once it is dissolved.
Responding to stimuli
Reconfigurable synthetic or artificial microswimmers need internal feedback Self-propelling microparticles are often proposed as synthetic models for biological microswimmers, yet they lack the internally regulated adaptation of their biological counterparts. Conversely, adaptation can be encoded in larger-scale soft-robotic devices but remains elusive to transfer to the colloidal scale.
The ubiquity and success of motile bacteria are strongly coupled to their ability to autonomously adapt to different environments as they can reconfigure their shape, metabolism, and motility via internal feedback mechanisms. Realizing artificial microswimmers with similar adaptation capabilities and autonomous behavior might substantially impact technologies ranging from optimal transport to sensing and microrobotics. Focusing on adaptation, existing approaches at the colloidal scale mostly rely on external feedback, either to regulate motility via the spatiotemporal modulation of the propulsion velocity and direction or to induce shape changes via the same magnetic or electric fields, which are also driving the particles. On the contrary, endowing artificial microswimmers with an internal feedback mechanism, which regulates motility in response to stimuli that are decoupled from the source of propulsion, remains an elusive task.
A promising route to achieve this goal is to exploit the coupling between particle shape and motility. For example, through simple shape design, platinum micromotors can execute a variety of motion trajectories, from highly linear to orbital, when exposed to hydrogen peroxide. Efficient switching between different propulsion states can, for instance, be reached by the spontaneous aggregation of symmetry-breaking active clusters of varying geometry, albeit this process does not have the desired deterministic control. Conversely, designing colloidal clusters with fixed shapes and compositions offers fine control on motility but lacks adaptation. Although progress on reconfigurable robots at the sub-millimeter scale has been made, downscaling these concepts to the colloidal level demands alternative fabrication and design. Shape-shifting colloidal clusters reconfiguring along a predefined pathway in response to local stimuli would combine both characteristics, with high potential toward the vision of realising adaptive artificial microswimmers.
Biohybrid microswimmers
The so-called biohybrid microswimmer can be defined as a microswimmer that consist of both biological and artificial parts, for instance, one or several living microorganisms attached to one or various synthetic parts. The biohybrid approach directly employs living microorganisms to be a main component or modified base of a functional microswimmer. Initially microorganisms were used as the motor units for artificial devices, but in recent years this role has been extended and modified toward other functionalities that take advantage of the biological capabilities of these organisms considering their means of interacting with other cells and living matter, specifically for applications inside the human body like drug delivery or fertilisation.
A distinct advantage of microorganisms is that they naturally integrate motility and various biological functions in a conveniently miniaturised package, coupled with autonomous sensing and decision-making capabilities. They are able to adapt and thrive in complex in vivo environments and are capable of self-repair and self-assembly upon interaction with their surroundings. In that sense, self-sufficient microorganisms naturally function very similar to what we envision for artificially created microrobots: They harvest chemical energy from their surroundings to power molecular motor proteins that serve as actuators, they employ ion channels and microtubular networks to act as intracellular wiring, they rely on RNA or DNA as memory for control algorithms, and they feature an array of various membrane proteins to sense and evaluate their surroundings. All these abilities act together to allow microbes to thrive and pursue their goal and function. In principle, these abilities also qualify them as biological microrobots for novel operations like theranostics, the combination of diagnosis and therapy, if we are able to impose such functions artificially, for example, by functionalisation with therapeutics. Further, artificial extensions may be used as handles for external control and supervision mechanisms or to enhance the microbe's performance to guide and tailor its functions for specific applications.
In fact, the biohybrid approach can be conceived in a dualistic way, with respect to the three basic ingredients of an in vivo microrobot, which are motility, control, and functionality. Figure 1 illustrates how these three ingredients can be either realized biologically, i.e., by the microorganism, or artificially, i.e., by the synthetic component. For example, a hybrid biomicromotor based on a sperm cell can be driven by the flagellum of the sperm or by an attached artificial helical flagellum. It can orient itself autonomously via biological interactions with its surroundings and other cells, or be controlled and supervised externally via artificial sensors and actuators. Finally, it can carry out a biological function, like its inherent ability to fertilize an egg cell, or an artificially imposed function, like the delivery of synthetic drugs or DNA vectors. A biohybrid device may deploy any feasible combination of such biological and artificial components in order to carry out a specific application.
Another example of the biohybrid approach is by designing a microswimmer that is designed for studying skeletal muscle stimulation. The microswimmer is fabricated from an Iron Oxide nanoparticles being dip-coated with chlorella microalgae allowing for the microrobot to be used in different biological environments while still having a high degree of control due to the superparamagnetic nanoparticles. Guided by an external magnetic field the microswimmer is capable of reaching its target. The microswimmer can be safely irradiated with a near-infrared (NIR) laser causing the nanoparticles to be heated through a photothermal effect and to trigger a targeted contraction in the skeletal muscle. This technique demonstrates a safe and controllable method for movement within a biological environment.
Navigation
Hydrodynamics can determine the optimal route for microswimmer navigation Compared to the well explored problem of how to steer a macroscopic agent, like an airplane or a moon lander, to optimally reach a target, optimal navigation strategies for microswimmers experiencing hydrodynamic interactions with walls and obstacles are far-less understood. Furthermore, hydrodynamic interactions in suspensions of microswimmers produce complex behavior.
The quest on how to navigate or steer to optimally reach a target is important, e.g., for airplanes to save fuel while facing complex wind patterns on their way to a remote destination, or for the coordination of the motion of the parts of a space-agent to safely land on the moon. These classical problems are well-explored and are usually solved using optimal control theory. Likewise, navigation and search strategies are frequently encountered in a plethora of biological systems, including the foraging of animals for food, or of T cells searching for targets to mount an immune response.
There is growing interest in optimal navigation problems and search strategies of microswimmers and "dry" active Brownian particles, The general problem regarding the optimal trajectory of a microswimmer which can freely steer but cannot control its speed toward a predefined target (point-to-point navigation) can be referred to as "the optimal microswimmer navigation problem". The characteristic differences between the optimal microswimmer navigation problem and conventional optimal control problems for macroagents like airplanes, cruise-ships, or moon-landers root in the presence of a low-Reynolds-number solvent in the former problem only. They comprise (i) overdamped dynamics, (ii) thermal fluctuations, and (iii) long-ranged fluid-mediated hydrodynamic interactions with interfaces, walls, and obstacles, all of which are characteristic for microswimmers. In particular, the non-conservative hydrodynamic forces which microswimmers experience call for a distinct navigation strategy than the conservative gravitational forces acting, e.g. on space vehicles. Recent work has explored optimal navigation problems of dry active particles (and particles in external flow fields) accounting for (i) and partly also for (ii). Specifically recent research has pioneered the use of reinforcement learning such as determining optimal steering strategies of active particles to optimally navigate toward a target position or to exploit external flow fields to avoid getting trapped in certain flow structures by learning smart gravitaxis. Deep reinforcement learning has been used to explore microswimmer navigation problems in mazes and obstacle arrays assuming global or only local knowledge of the environment. Analytical approaches to optimal active particle navigation complement these works and allow testing machine-learned results.
An example of a successful machine learning locomotion being used in navigation is by Zou et al. where it was inspired by microorganisms having the ability to naturally switch between locomotory gaits such as a run-and-tumble or a roll-and-flick motion depending on the need to navigate the environment. The artificial intelligence system allowed for the development of distinct gaits for steering, transition, and translational movement.
Applications
As is the case for microtechnology and nanotechnology in general, the history of microswimmer applications arguably starts with Richard Feynman’s famous lecture There's Plenty of Room at the Bottom. In the visionary speech, among other topics, Feynman addressed the idea of microscopic surgeons, saying: "...it would be interesting in surgery if you could swallow the surgeon. You put the mechanical surgeon inside the blood vessel and it goes into the heart and <<looks>> around (of course the information has to be fed out). It finds out which valve is the faulty one and takes a little knife and slices it out. Other small machines might be permanently incorporated in the body to assist some inadequately-functioning organ." The concept of the surgeon one could swallow was soon after presented in the science-fiction movie Fantastic Voyage and in Isaac Asimov’s writings.
Only a few decades later, microswimmers aiming to become true microscale surgeons evolved from an intriguing science-fiction concept to a reality explored in many research laboratories around the world, as already highlighted by Metin Sitti in 2009. These active agents that can self-propel in a low Reynolds number environment might play a key role in the future of nanomedicine, as popularised in 2016 by Yuval Noah Harari in Homo Deus: A Brief History of Tomorrow. In particular, they might become useful for the targeted delivery of genes or drugs and other cargo to a certain target (e.g. a cancer cell) through our blood vessels, requiring them to find a good, or ideally optimal, path toward the target avoiding, e.g., obstacles and unfortunate flow field regions.
Already in 2010, Nelson et al. reviewed the existing and envisioned applications of microrobots in minimally invasive medicine. Since then, the field has grown, and it has become clear that microswimmers have much potential for biomedical applications. Already, many interesting tasks can be performed in vitro using tailored microswimmers. Still, as of 2020, a number of challenges regarding in vivo control, biocompatibility and long-term biosafety need to be overcome before microswimmers can become a viable option for many clinical applications.
A schematic representation of the classification of biomedical applications is shown in the diagram on the left below. This includes the use of microswimmers for cargo transport in drug delivery and other biomedical applications, as well as assisted fertilisation, sensing, micromanipulation and imaging. Some of the more complex microswimmers fit into multiple categories, as they are applied simultaneously for e.g., sensing and drug delivery.
The design of an untethered microscopic mobile machine or microrobot to function in vivo with medical interventional capabilities should assume an integrated approach where design 3D body shape, material composition, manufacturing technique, deployment strategy, actuation and control methods, imaging modality, permeation of biological barriers, and the execution of the prescribed medical tasks need to be considered altogether, as illustrated in the diagram on the right above. Each of these essential aspects contains a special design consideration, which must be reflected at the physical design of the microrobot.
Delivering therapeutic agents to precise locations in deep tissue remains a significant challenge since magnetic actuation becomes less effective as the magnetic flux density weakens farther away from the electromagnetic control platform. Biohybrid microswimmers have demonstrated promise in drug delivery, capable of precise drug delivery to deep tissue cancer tumors, and one such example is magnetostatic bacteria. Magnetostatic bacteria (MTB) were discovered in the 1970s, and since then, their mechanism and dynamics have been heavily studied. Microaerophilic alphaproteobacterium Magnetospirillum gryphiswaldense is one of the most well-characterized magnetostatic bacteria, and it contains a prominent amount of magnetite Fe3O4 which acts internal compass that guides the bacteria with the surrounding magnetic field. A recent study by Mirkhani N, et al. demonstrated drug delivery using rotating magnetic fields (RMF) controlled magnetostatic bacteria (MTB) on a mouse tumor model. RMF concentrates magnetic torque density within specific regions by inducing a magnetostatic selection field with a field-free point or field-free line. Experimental validation using the mouse tumor model has confirmed the efficacy of the RMF control in enhancing the translational velocity and the penetration of MTB into deep tissues. This strategy holds the potential for systemic drug delivery with heightened spatial selectivity.
Another proposed application is for microswimmers to help improve the protection of the environment by reducing the amount of waste and pollutants in different parts of the environment. Some examples of pollutants that can be reduced or removed from the field include microplastics, oil-based chemicals, and other waste. A wide variety of microswimmers are being developed in research labs for this purpose using different variants of actuation systems using different multiphysics including light, magnetic, and chemical gradients. One example is the removal of Bisphenol A (BPA) which is a common waste product from factories producing plastics-based products. One example is a microswimmer developed by Dekanovsky et al. using a Mxene-based microswimmer which is controlled by light. The propulsion system has two components one being the Mxene component grafted with nanoparticles and an iron oxide layer. The components within the propulsion system produce a chemical reaction with BPA where the products produce oxygen bubbles which can propel the microswimmer forward. Research is being conducted on designing synthetic microswimmers to react with other waste chemicals to reduce pollution in the environment. Many of the current synthetic microswimmers are being designed to use a multiphysics propulsion system with a magnetic force along with a chemical or optical-based system.
See also
Bioinspiration
Bio-inspired robotics
Bio-inspired engineering
Gray goo
Robotic sperm
Soft robotics
Squirmer
References | Microswimmer | [
"Physics"
] | 8,435 | [
"Microswimmers",
"Physical phenomena",
"Motion (physics)"
] |
69,135,975 | https://en.wikipedia.org/wiki/List%20of%20fungi%20of%20South%20Africa%20%E2%80%93%20F | This is an alphabetical list of fungal taxa as recorded from South Africa. Currently accepted names have been appended.
Fa
Genus: Fabraea Sacc. 1881 accepted? as Leptotrochila P. Karst., (1871)
Fabraea litigiosa Sacc. (sic) possibly (Roberge ex Desm.) Gillet 1886
Fabraea maculata (Lév.) G.F. Atk. 1951 accepted as Diplocarpon mespili (Sorauer) B. Sutton, 1980)
Genus: Farysia Racib. 1909
Farysia olivacea (DC.) Syd. & P. Syd. 1920 accepted as Farysia thuemenii (A.A. Fisch. Waldh.) Nannf., (1959)
Genus: Favolus Fr., (1828)
Favolus agariceus (Berk.) Lév. 1844 accepted as Lentinus arcularius (Batsch) Zmitr., (2010)
Favolus brasiliensis (Fr.) Fr. 1830 accepted as Favolus tenuiculus P. Beauv., (1806)
Favolus dermoporus Torrend ex Lloyd.(sic) possibly (Pers.) Lév. 1846 accepted as Favolus tenuiculus P. Beauv., (1806)
Favolus europaeus Fr. 1838
Favolus friesii Berk. & M.A. Curtis 1868
Favolus jacobaeus Sacc. & Berl. 1889
Favolus megaloporus Bres. 1912
Favolus moluccensis Mont. 1843 accepted as Royoporus spatulatus (Jungh.) A.B. De [as 'spathulatus'], (1996)
Favolus multiplex Lév. 1844, [as 'multiple'] accepted as Favolus grammocephalus (Berk.) Imazeki, (1943)
Favolus natalensis Fr. 1848
Favolus rhipidium (Berk.) Sacc. 1888 accepted as Panellus pusillus (Pers. ex Lév.) Burds. & O.K. Mill., (1975)
Favolus spathulatus Bres. (sic) possibly Favolus spatulatus (Jungh.) Lév. [as spathulatus], (1844) accepted as Royoporus spatulatus (Jungh.) A.B. De [as spathulatus], (1996)
Favolus tenuiculus P. Beauv., (1806) reported as Favolus brasiliensis (Fr.) Fr. 1830, Favolus tessellatus Mont. (1843) [as tesselatus] and possibly Favolus dermoporus Torrend ex Lloyd.(sic)
Favolus tessellatus Mont. (1843) [as tesselatus] accepted as Favolus tenuiculus P. Beauv., (1806)
Genus: Favotrichophyton (Castell. & Chalm.) Neveu-Lem. 1921 accepted as Trichophyton Malmsten, (1848)
Favotrichophyton violaceum (Sabour. ex E. Bodin) C.W. Dodge 1935 accepted as Trichophyton violaceum Sabour. ex E. Bodin, (1902)
Fe
Genus: Femsjonia Fr. 1849 accepted as Ditiola Fr., (1822)
Femsjonia natalensis Cooke 1882;
Genus: Ferrarisia Sacc. 1919
Ferrarisia jasmini Doidge 1942 accepted as Palawaniella jasmini (Doidge) Arx & E. Müll., (1975)
Fi
Family: Fistuliniodeae*
Genus: Fistulina Bull. 1791
Fistulina africana Van der Byl 1928
Fl
Genus: Flammula (Fr.) P. Kumm. 1871
Flammula alnicola Quel. {sic} poaaibly (Fr.) P. Kumm. 1871
Flammula flavida Quel. (sic) possibly (Schaeff.) P. Kumm. 1871 accepted as Pholiota flavida (Schaeff.) Singer, [1949]
Flammula harmoge Karst. (sic) possibly (Fr.) Sacc. 1887
Flammula hybrida Gillet 1876, accepted as Gymnopilus hybridus (Gillet) Maire, (1933)
Flammula janus (Berk. & Broome) Sacc. 1887
Flammula sapinea Quel. (sic) possibly (Fr.) P. Kumm. 1871 accepted as Gymnopilus sapineus (Fr.) Murrill, (1912)
Flammula tilopus (Kalchbr. & MacOwan) Sacc. 1887 accepted as Pholiota tilopus (Kalchbr. & MacOwan) D.A. Reid, (1975)
Fo
Genus: Fomes (Fr.) Fr. 1849
Fomes albomarginatus (Zipp. ex Lév.) Cooke 1885, accepted as Skeletocutis albomarginata (Zipp. ex Lév.) Rui Du & Y.C. Dai, (2020)
Fomes annosus (Fr.) Cooke 1885 accepted as Heterobasidion annosum (Fr.) Bref., (1888)
Fomes annularis Lloyd 1912 accepted as Ganoderma australe (Fr.) Pat., (1889)
Fomes applanatus Karst (sic) possibly (Pers.) Fr. 1849 accepted as Ganoderma applanatum (Pers.) Pat., (1887)
Fomes australis (Fr.) Cooke 1885 accepted as Ganoderma australe (Fr.) Pat., (1889)
Fomes badius Cooke 1885 accepted as Phellinus badius (Cooke) G. Cunn., (1965)
Fomes caryophylli (Racib.) Bres. 1912, accepted as Phellinus caryophylli (Racib.) G. Cunn., (1965)
Fomes chilensis Cooke. (sic) possibly (Fr.) Sacc. 1888, accepted as Ganoderma chilense (Fr.) Pat., (1889)
Fomes conchatus (Pers.) Gillet 1878, accepted as Phellinopsis conchata (Pers.) Y.C. Dai, (2010)
Fomes connatus (Weinm.) Gillet 1878 accepted as Oxyporus populinus (Schumach.) Donk, (1933)
Fomes curtisii (Berk.) Cooke 1885, accepted as Ganoderma curtisii (Berk.) Murrill, (1908)
Fomes dialeri Bres. & Torrend [as 'dialerii'],(1905) accepted as Phellinus rimosus (Berk.) Pilát, (1940)
Fomes durissimus Lloyd 1920 accepted as Fulvifomes durissimus (Lloyd) Bondartseva & S. Herrera, (1992)
Fomes endotheius Cooke (sic) possibly (Berk.) Sacc. 1888
Fomes fastuosus (Lév.) Cooke 1885 accepted as Phellinus fastuosus (Lév.) S. Ahmad, (1972)
Fomes focalis Cooke (sic) possibly (Kalchbr.) Sacc. 1888
Fomes fomentarius Kockx (sic) possibly (L.) Fr. 1849,
Fomes fulvus (Scop.) Gillet 1878
Fomes fusco-purpureus Boud.(sic) possibly Fomes fuscopurpureus Cooke [as fusco-purpureus], (1885)
Fomes geotropus (Cooke) Cooke 1885 accepted as Rigidoporus ulmarius (Sowerby) Imazeki, (1952)
Fomes glaucoporus Lloyd 1915 accepted as Perenniporia inflexibilis (Berk.) Ryvarden, (1972)
Fomes hemileucus(Berk. & M.A. Curtis) Sacc. 1885 accepted as Fomitella supina (Sw.) Murrill, (1905)
Fomes hornodermus (Mont.) Cooke 1885, accepted as Perenniporia martia (Berk.) Ryvarden (1972)
Fomes igniarius Kickx (sic) possibly (L.) Fr. 1849 accepted as Phellinus igniarius (L.) Quél., (1886)
Fomes kermes Cooke (sic) possibly (Berk. & Broome) Sacc. 1888
Fomes leucophaeus (Mont.) Cooke 1885 accepted as Ganoderma applanatum (Pers.) Pat., (1887)
Fomes lividus Cooke (sic)possibly (Kalchbr.) Sacc. 1888, accepted as Truncospora livida (Kalchbr. ex Cooke) Zmitr., (2018)
Fomes lucidus Levss. ex Fr. (sic) possibly (Curtis) Sacc. 1888 accepted as Ganoderma lucidum (Curtis) P. Karst., (1881)
Fomes mastoporus (Lév.) Cooke 1885 accepted as Ganoderma orbiforme (Fr.) Ryvarden (2000)
Fomes mcgregori Bres. 1912 accepted as Fulvifomes mcgregorii (Bres.) Y.C. Dai [as 'macgregorii'], (2010)
Fomes melanoporus Cooke (sic) possibly (Mont.) Sacc. 1885, accepted as Nigrofomes melanoporus (Mont.) Murrill, (1904)
Fomes minutulus Henn. 1895, accepted as Perenniporia inflexibilis (Berk.) Ryvarden, (1972)
Fomes mundulus Wakef. 1936 accepted as Perenniporia mundula (Wakef.) Ryvarden, (1972)
Fomes niaouli (Pat.) Lloyd 1915 accepted as Phellinus rimosus (Berk.) Pilát, (1940)
Fomes nubilis Cooke var. albo-limbatus Kalchbr.(sic) possibly Fomes nubilus var. albolimbatus (Cooke) Sacc. 1888
Fomes oroflavus Lloyd 1915 accepted as Ganoderma australe (Fr.) Pat., (1889)
Fomes pectinatus (Klotzsch) Gillet 1885 accepted as Phylloporia pectinata (Klotzsch) Ryvarden, (1991)
Fomes pinicola Cooke (sic) possibly (Sw.) Fr. 1849 accepted as Fomitopsis pinicola (Sw.) P. Karst., (1881)
Fomes pseudosenex (Murrill) Sacc. & Trotter 1912
Fomes rimosus (Berk.) Cooke 1885 accepted as Phellinus rimosus (Berk.) Pilát, (1940)
Fomes robinsoniae (Murrill) Sacc. & Trotter 1912 accepted as Fuscoporia wahlbergii (Fr.) T. Wagner & M. Fisch., (2001)
Fomes robustus P. Karst. 1889 accepted as Fomitiporia robusta (P. Karst.) Fiasson & Niemelä, (1984)
Fomes salicinus Kirckx. (sic) possibly (Pers. ex J.F. Gmel.) Gillet 1878, accepted as Phellinopsis conchata (Pers.) Y.C. Dai, (2010)
Fomes senex (Nees & Mont.) Cooke 1885 accepted as Fuscoporia senex (Nees & Mont.) Ghob.-Nejh., (2007)
Fomes torulosus (Pers.) Lloyd 1910 accepted as Fuscoporia torulosa (Pers.) T. Wagner & M. Fisch., (2001)
Fomes umbraculum (Fr.) Sacc. 1888
Fomes vegetus Cooke (sic) possibly (Fr.) Fr. 1849
Fomes yucatanensis (Murrill) Sacc. & D. Sacc. 1905 accepted as Phellinus yucatanensis (Murrill) Imazeki [as yucatensis], (1943)
Fomes zambesianus (Lloyd) Sacc. & Trotter 1925, accepted as Amauroderma preussii (Henn.) Steyaert, (1972)
Fomes zuluensis Wakef. 1948 accepted as Fomitopsis zuluensis (Wakef.) Ryvarden [as zuuluensis], (1972)
Genus Fomitella
Fomitella supina (Sw.) Murrill, (1905) recorded as Fomes hemileucus(Berk. & M.A. Curtis) Sacc. 1885
Fr
Genus: Fracchiaea Sacc. 1873
Fracchiaea heterogenea Sacc. 1873
Fr
Genus: Fumago Pers. 1822
Fumago vagans Pers. 1822
Fu
Genus: Fusarium Link 1809
Fusarium acuminatum Ellis & Everh., (1895) recorded as Fusarium scirpi Lambotte & Fautrey 1894
Fusarium aloes Kalchbr. & Cooke 1880
Fusarium angustum Sherb. 1915 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium argillaceum (Fr.) Sacc. 1886 accepted as Rectifusarium ventricosum (Appel & Wollenw.) L. Lombard & Crous, (2015)
Fusarium avenaceum (Fr.) Sacc. 1886
Fusarium avenaceum f. 1 Wollenw. & Reinking possibly Fusarium avenaceum var. volutum (Wollenw.) Wollenw. & Reinking, (1935) accepted as Fusarium avenaceum (Fr.) Sacc., (1886)
Fusarium baccharidicola Henn. 1908
Fusarium bulbigenum Cooke & Massee 1887 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium bulbigenum var. blasticola (Rostr.) Wollenw. 1931 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium bulbigenum var. lycopersici (Sacc.) Wollenw. & Reinking 1930 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium bulbigenum var. niveum (E.F. Sm.) Wollenw. 1931 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium bulbigenum var. tracheiphilum (E.F. Sm.) Wollenw. 1931 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium cepae Hanzawa 1914 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium chlamydosporum Wollenw. & Reinking 1925
Fusarium ciliatum Link 1825
Fusarium coccinellum Kalchbr. 1875
Fusarium coccophilum (Desm.) Wollenw. & Reinking 1935 accepted as Microcera coccophila Desm., (1848)
Fusarium coeruleum Sacc.
Fusarium compactum (Wollenw.) Raillo, (1950) recorded as Fusarium scirpi var. compactum Wollenw. 1930
Fusarium conglutinans Wollenw. 1913 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium conglutinans var. callistephi Beach 1918 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium conglutinans var. majus Wollenw. 1930 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium congoense Wollenw. 1916 accepted as Fusarium heterosporum Nees & T. Nees, (1818)
Fusarium congoense var. septatius Wollenw. 1924
Fusarium culmorum (Wm.G. Sm.) Sacc. 1892
Fusarium decemcellulare Brick 1908 accepted as Albonectria rigidiuscula (Berk. & Broome) Rossman & Samuels, (1999)
Fusarium dianthi Prill. & Delacr. 1899 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium dimerum Penz. 1882 accepted as Bisifusarium dimerum (Penz.) L. Lombard & Crous, (2015)
Fusarium diversisporum Sherb. 1915 [as diversisporium]
Fusarium equiseti (Corda) Sacc. 1886
Fusarium equiseti var. bullatum (Sherb.) Wollenw. 1930 accepted as Fusarium gibbosum Appel & Wollenw., (1910) [1913]
Fusarium expansum Schltdl. 1824
Fusarium filiferum (Preuss) Wollenw., (1916) recorded as Fusarium scirpi var. filiferum (Preuss) Wollenw. 1916
Fusarium graminearum Schwabe 1839
Fusarium granulare Kalchbr. 1882 as granulari
Fusarium heterosporum Nees & T. Nees 1818
Fusarium heterosporum var. congoense (Wollenw.) Wollenw. 1931 [as congoensis]
Fusarium incarnatum (Desm.) Sacc. 1886
Fusarium javanicum Koord. 1907 accepted as Fusarium solani (Mart.) Sacc., (1881)
Fusarium javanicum var. radicicola Wollenw. 1931 accepted as Fusarium solani (Mart.) Sacc., (1881)
Fusarium lateritium Nees 1816
Fusarium lateritium var. longum Wollenw. 1916 accepted as Fusarium stilboides Wollenw., (1924)
Fusarium lateritium var. majus (Wollenw.) Wollenw. 1930 accepted as Fusarium lateritium Nees, (1816) [1816-17]
Fusarium lini Bolley 1901 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium lycopersici Bruschi 1912 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium moniliforme J. Sheld. 1904 accepted as Fusarium fujikuroi Nirenberg, (1976)
Fusarium moniliforme var. erumpens Wollenw. & Reinking 1925 accepted as Fusarium fujikuroi Nirenberg, (1976)
Fusarium moniliforme var. subglutinans Wollenw. & Reinking 1925 accepted as Fusarium fujikuroi Nirenberg, (1976)
Fusarium orthoceras Appel & Wollenw. 1910 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium orthoceras var. albidoviolaceum (Dasz.) Wollenw. 1916 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium neocosmosporiellum O'Donnell & Geiser, (2013) recorded as Fusarium vasinfectum var. pisi C.J.J. Hall 1903
Fusarium orthoceras var. longius (Sherb.) Wollenw. 1916 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium oxysporum Schltdl. 1824,
Fusarium oxysporum f. 1 Wollenw.*
Fusarium oxysporum f. 7 Wollenw.*
Fusarium oxysporum f. 8 Snyder.*
Fusarium oxysporum var. aurantiacum (Link) Wollenw. 1931 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium oxysporum var. cubense (E.F. Sm.) Wollenw. 1935 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium oxvsporum var. gladioli Massey 1926 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium oxysporum var. nicotianae J. Johnson 1920 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium pallidoroseum (Cooke) Sacc., (1886) recorded as Fusarium semitectum var. majus Wollenw. 1930
Fusarium putaminum (Thüm.) Sacc. 1886
Fusarium redolens Wollenw. f. 1 Wollenw. possibly Fusarium redolens Wollenw. 1913
Fusarium reticulatum Mont. f. 1 Wollenw. possibly Fusarium reticulatum Mont. 1843
Fusarium roseum Kalchbr. (sic) possibly Link 1809
Fusarium sambucinum Fuckel 1870 accepted as Fusarium roseum Link, (1809)
Fusarium sambucinum f. 2 Wollenw. probably accepted as Fusarium roseum Link, (1809)
Fusarium sambucinum f. 6 Wollenw. probably accepted as Fusarium roseum Link, (1809)
Fusarium scirpi Lambotte & Fautrey 1894 accepted as Fusarium acuminatum Ellis & Everh., (1895)
Fusarium scirpi var. acuminatum (Ellis & Everh.) Wollenw. 1930 accepted as Fusarium acuminatum Ellis & Everh., (1895)
Fusarium scirpi var. compactum Wollenw. 1930 accepted as Fusarium compactum (Wollenw.) Raillo, (1950)
Fusarium scirpi var. filiferum (Preuss) Wollenw. 1916 accepted as Fusarium filiferum (Preuss) Wollenw., (1916)
Fusarium semitectum var. majus Wollenw. 1930 accepted as Fusarium pallidoroseum (Cooke) Sacc., (1886)
Fusarium solani Appel & Wollenw. (sic)(Mart.) Sacc. 1881
Fusarium solani var. martii f. 1 Wollenw. possibly (Appel & Wollenw.) Wollenw. 1930 accepted as F solani (Mart.) Sacc. 1881
Fusarium solani var. martii f. 2 Snyder**
Fusarium sporotrichioides Sherb. 1915
Fusarium stilboides Wollenw. 1924
Fusarium vasinfectum G.F. Atk. 1892 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium vasinfectum f. 2 Wollenw. & Reinking**
Fusarium vasinfectum var. lutulatum (Sherb.) Wollenw. 1930 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium vasinfectum var. pisi C.J.J. Hall 1903 accepted as Fusarium neocosmosporiellum O'Donnell & Geiser, (2013)
Fusarium vasinfectum var. zonatum (Sherb.) f. 1 Wollenw. probably var. zonatum (Sherb.) Wollenw. 1930 accepted as Fusarium oxysporum Schltdl., (1824)
Fusarium vasinfectum var. zonatum f. 2 Wollenw.**
Fusarium sp.
Genus: Fusella Sacc. 1886
Fusella zambeziana Torrend 1914 [as zambesiana]
Genus: Fusicladium Bonord. 1851 accepted as Venturia Sacc., (1882)
Fusicladium crataegi Aderh. 1902 accepted as Venturia crataegi Aderh., (1902)
Fusicladium dendriticum (Wallr.) Fuckel 1870 accepted as Venturia inaequalis (Cooke) G. Winter, (1875)
Fusicladium dendriticum var. eriobotryae Scalia 1901 accepted as Venturia inaequalis (Cooke) G. Winter, (1875)
Fusicladium eriobotryae (Cavara) Sacc. 1892 accepted as Fusicladium pyracanthae (Thüm.) O. Rostr., (1912)
Fusicladium fuliginosum Kalchbr. & Cooke 1880
Fusicladium pyrorum (Lib.) Fuckel [as pirinum],(1870) accepted as Venturia pyrina Aderh. [as 'pirina'], (1896)
Fusicladium pirinum var. pyracanthae probably Fusicladium pyrorum var. pyracanthae Thüm. 1877, accepted as Fusicladium pyracanthae (Thüm.) O. Rostr., (1912)
Genus: Fusicoccum Corda 1829,
Fusicoccum africanum Van der Byl 1927
Fusicoccum viticola Reddick 1909, [as viticolum] accepted as Diaporthe neoviticola Udayanga, Crous & K.D. Hyde, (2012)
See also
List of bacteria of South Africa
List of Oomycetes of South Africa
List of slime moulds of South Africa
List of fungi of South Africa
List of fungi of South Africa – A
List of fungi of South Africa – B
List of fungi of South Africa – C
List of fungi of South Africa – D
List of fungi of South Africa – E
List of fungi of South Africa – F
List of fungi of South Africa – G
List of fungi of South Africa – H
List of fungi of South Africa – I
List of fungi of South Africa – J
List of fungi of South Africa – K
List of fungi of South Africa – L
List of fungi of South Africa – M
List of fungi of South Africa – N
List of fungi of South Africa – O
List of fungi of South Africa – P
List of fungi of South Africa – Q
List of fungi of South Africa – R
List of fungi of South Africa – S
List of fungi of South Africa – T
List of fungi of South Africa – U
List of fungi of South Africa – V
List of fungi of South Africa – W
List of fungi of South Africa – X
List of fungi of South Africa – Y
List of fungi of South Africa – Z
References
Sources
Further reading
Fungi F
South Africa | List of fungi of South Africa – F | [
"Biology"
] | 5,874 | [
"Fungi",
"Lists of fungi"
] |
69,136,119 | https://en.wikipedia.org/wiki/List%20of%20fungi%20of%20South%20Africa%20%E2%80%93%20G | This is an alphabetical list of fungal taxa as recorded from South Africa. Currently accepted names have been appended.
Ga
Genus: Galera (Fr.) P. Kumm. 1871
Galera eatoni (Berk.) Sacc
Galera hypnorum (Batsch) Quél. 1872
Galera lateritia Quel. (sic) possibly (Fr.) P. Kumm. 1871
Galera peroxydata (Berk.) Sacc. 1887, accepted as Conocybe peroxydata (Berk.) D.A. Reid, (1975)
Galera pygmaeo-affinis (Fr.) Quél. 1872, accepted as Conocybe pygmaeoaffinis (Fr.) Kühner, (1935)
Galera spartea Quel. (sic) possibly (Fr.) P. Kumm. 1871, accepted as Conocybe spartea (Fr.) Konrad & Maubl., (1949) [1948]
Galera sphagnorum Karst. (sic) possibly (Pers.) Sacc. 1887, accepted as Galerina sphagnorum (Pers.) Kühner, (1935)
Galera tenera Quel. (sic) possibly (Schaeff.) P. Kumm. 187,1 accepted as Conocybe tenera (Schaeff.) Kühner, (1935)
Galera tenera var. siliginea Quel. (sic) possibly (Fr.) P. Kumm. 1871, accepted as Conocybe siliginea (Fr.) Kühner, (1935)
Genus: Ganoderma P. Karst. 1881
Ganoderma africanum (Lloyd) Doidge 1950
Ganoderma alluaudi Pat. & Har. 1906
Ganoderma applanatum (Pers.) Pat. 1887
Ganoderma applanatum var. laccatum (Sacc.) Rea 1922 accepted as Ganoderma pfeifferi Bres., (1889)
Ganoderma australe (Fr.) Pat. 1889
Ganoderma chilense (Fr.) Pat. 1889
Ganoderma colossus Bres.(sic) [as colossum] possibly (Fr.) C.F. Baker 1920
Ganoderma curtisii (Berk.) Murrill 1908
Ganoderma emini Henn. 1893 accepted as Humphreya eminii (Henn.) Ryvarden, (1980)
Ganoderma fulvellum Bres. 1889 accepted as Fomes fulvellus (Bres.) Sacc., (1891)
Ganoderma lobatum Atk. (sic) possibly Bres. 1889, accepted as Fomes fulvellus (Bres.) Sacc., (1891)
Ganoderma lucidum (Curtis) P. Karst. 1881
Ganoderma mastoporum (Lév.) Pat. 1889 accepted as Ganoderma orbiforme (Fr.) Ryvarden [as orbiformum], (2000)
Ganoderma mollicarnosum (Lloyd) Sacc. & Trotter 1925 accepted as Navisporus floccosus (Bres.) Ryvarden [as floccosa], (1980)
Ganoderma obockense Pat. (1887) [as obockense]
Ganoderma oerstedii Bres. (sic) possibly (Fr.) Torrend 1902
Ganoderma oroflavum (Lloyd) C.J. Humphrey 1931 accepted as Ganoderma australe (Fr.) Pat., (1889)
Ganoderma resinaceum Boud. 1889
Ganoderma rugosum Bres. (sic) possibly (Blume & T. Nees) Pat. 1889, or Ganoderma rugosum var. nigrozonatum Bres. 1915, both accepted as Sanguinoderma rugosum (Blume & T. Nees) Y.F. Sun, D.H. Costa & B.K. Cui, (2020)
Genus: Gassicurtia Fée 1825
Gassicurtia silacea Fée 1834 [as Gassicourtia silicea] accepted as Coniothecium silaceum (Fée) Keissl., (1930)
Family: Gasteromyceteae*
Ge
Genus: Geaster P. Micheli 1729 accepted as Geastrum Pers., (1794)
Geaster affinis Colenso. accepted as Geastrum affine Colenso (1884) [1883]
Geaster calceus Lloyd. accepted as Geastrum calceum Lloyd (1907)
Geaster capensis Thuem. accepted as Geastrum capense Thüm. (1877)
Geaster coliformis Dicks. accepted as Geastrum coliforme (Dicks.) Pers. (1801)
Geaster coriaceus Colenso. accepted as Geastrum coriaceum Colenso (1890) [1889]
Geaster coronatus Schroet. accepted as Geastrum coronatum Schaeff. ex J. Schröt. (1889)
Geaster drummondii Berk. accepted as Geastrum drummondii Berk. 1845
Geaster fenestratum Fisch. (sic) probably accepted as Geastrum fenestratum (Batsch) Lloyd 1901
Geaster granulosus Fuck. accepted as Geastrum granulosum Fuckel 1860
Geaster macowani Kalchbr. accepted as Geastrum macowanii Kalchbr. 1882
Geaster minimus Fisch.*
Geaster plicatus Berk.*
Geaster schmidelii Vit. accepted as Geastrum schmidelii Vittad. 1842
Geaster schweinfurthii P.Henn. accepted as Geastrum schweinfurthii Henn. 1891
Geaster striatulus Kalchbr. accepted as Geastrum striatulum Kalchbr. 1880
Genus: Geasteropsis Hollós 1903 accepted as Geastrum Pers., (1794)
Geasteropsis conrathii Hollós 1903 [as conrathi] accepted as Geastrum conrathii (Hollós) P. Ponce de León, (1968)
Family: Geastreae
Genus: Geastrum Pers. 1794
Geastrum ambiguum Mont. 1837
Geastrum arenarium Lloyd 1907
Geastrum bryantii Berk. 1860 accepted as Geastrum striatum DC. [as Geaster], (1805)
Geastrum campestre Morgan 1887
Geastrum conrathii (Hollós) P. Ponce de León, (1968) recorded as Geasteropsis conrathii Hollós 1903 [as conrathi]
Geastrum corollinum (Batsch) Hollós, (1904) reported as Geastrum mammosum Chevall. 1826
Geastrum dissimile Bottomley 1948.
Geastrum fimbriatum Fr. 1829
Geastrum floriforme Vittad. 1842
Geastrum fornicatum Fr. (sic) possibly (Huds.) Hook. 1821
Geastrum hieronymi Henn. 1897
Geastrum hygrometricum Pers. 1801 accepted as Astraeus hygrometricus (Pers.) Morgan, (1889)
Geastrum limbatum Fr. 1829
Geastrum limbatum var. ellipsostoma N.J.G.*
Geastrum macowani Kalchbr. 1882.
Geastrum mammosum Chevall. 1826 accepted as Geastrum corollinum (Batsch) Hollós, (1904)
Geastrum minimum Schwein. 1822
Geastrum mirabile Mont. 1855
Geastrum nanum Pers. 1809 accepted as Geastrum striatum DC. [as Geaster], (1805)
Geastrum pazschkeanum Henn. 1900
Geastrum pectinatum Pers. 1801
Geastrum quadrifidum Pers. 1794
Geastrum saccatum Fr. 1829
Geastrum triplex Jungh. 1840
Geastrum velutinum Morgan 1895
Family: Geoglossaceae Corda 1838
Genus: Geopyxis (Pers.) Sacc. 1889
Geopyxis aluticolor (Berk.) Sacc. 1889
Geopyxis ammophila Dur. & Mont. (sic) possibly Sacc. 1889, accepted as Peziza ammophila Durieu & Lév., (1848)
Geopyxis cupularis (L.) Sacc. 1889 accepted as Tarzetta cupularis (L.) Lambotte, (1887)
Genus: Geotrichum Link 1809
Geotrichum rugosum (Castell.) C.W. Dodge 1935
Geotrichum sp.
Gi
Genus: Gibellula Cavara 1894
Gibellula aranearum P. Syd. 1922
Gibellula haygarthii Van der Byl 1922
Genus: Gibbera Fr. 1825
Gibbera engleriana (Henn.) Van der Byl 1928
Gibbera tinctoria Massee 1911
Genus: Gibberella Sacc. 1877 accepted as Fusarium Link, (1809)
Gibberella acuminata Wollenw. 1943 accepted as Fusarium acuminatum Ellis & Everh., (1895)
Gibberella baccata (Wallr.) Sacc. 1878, accepted as Fusarium lateritium Nees, (1816)
Gibberella fujikuroi Wollenw. (sic) possibly (Sawada) S. Ito 1919 accepted as Fusarium fujikuroi Nirenberg, (1976)
Gibberella fujikuroi var. subglutinans E.T. Edwards 1933 accepted as Fusarium fujikuroi Nirenberg, (1976)
Gibberella intricans Wollenw. 1930 accepted as Fusarium gibbosum Appel & Wollenw., (1910)
Gibberella pulicaris (Kunze) Sacc. 1877 accepted as Fusarium roseum Link, (1809)
Gibberella saubinetii (Mont.) Sacc. 1879 accepted as Fusarium graminearum Schwabe, (1839)
Gl
Genus: Gliocladium Corda 1840, accepted as Sphaerostilbella (Henn.) Sacc. & D. Sacc., (1905)
Gliocladium deliquescens Sopp 1912 accepted as Trichoderma deliquescens (Sopp) Jaklitsch, (2011)
Gliocladium penicillioides Corda 1840 [as penicilloides] accepted as Sphaerostilbella penicillioides (Corda) Rossman, L. Lombard & Crous, (2015)
Gliocladium roseum Bainier 1907 accepted as Clonostachys rosea (Link) Schroers, Samuels, Seifert & W. Gams, (1999)
Genus: Gloeodes Colby 1920
Gloeodes pomigena (Schwein.) Colby 1920
Genus: Gloeoporus Mont. 1842
Gloeoporus conchoides Mont. 1842 accepted as Gloeoporus thelephoroides (Hook.) G. Cunn., (1965)
Gloeoporus dichrous (Fr.) Bres. 1912 accepted as Vitreoporus dichrous (Fr.) Zmitr., (2018)
Gloeoporus thelephoroides (Hook.) G. Cunn., (1965) reported as Gloeoporus conchoides Mont. 1842
Genus: Gloeosoma Bres. 1920, accepted as Aleurodiscus Rabenh. ex J. Schröt., (1888)
Gloeosoma capensis (Lloyd) Lloyd 1920, accepted as Aleurocystis capensis (Lloyd) Lloyd, (1920)
Genus: Gloeosporium Desm. & Mont. 1849, accepted as Diplocarpon F.A. Wolf, (1912)
Gloeosporium affineSacc. 1878
Gloeosporium ampelophagum de Bary (sic) possibly (Pass.) Sacc. 1878, accepted as Elsinoe ampelina Shear, (1929)
Gloeosporium amygdalinum Brizi (sic) possibly (Pass.) Sacc. 1878, accepted as Elsinoe ampelina Shear, (1929)
Gloeosporium cocophilum Wakef. 1913 accepted as Colletotrichum gloeosporioides (Penz.) Penz. & Sacc., (1884)
Gloeosporium crocatum Sacc. 1891
Gloeosporium epicarpi Thüm. 1877
Gloeosporium fructigenum Berk. 1856 accepted as Colletotrichum gloeosporioides (Penz.) Penz. & Sacc., (1884)
Gloeosporium cydoniae Mont. 1851
Gloeosporium helichrysi G. Winter 1885 accepted as Colletotrichum helichrysi (G. Winter) Arx, (1957)
Gloeosporium lagenaria (Pass.) Sacc. & Roum. [as lagenarium], (1880) accepted as Gloeosporium orbiculare (Berk.) Berk., (1876)
Gloeosporium limetticola R.E. Clausen 1912, [as 'limetticolum'] accepted as Colletotrichum limetticola (R.E. Clausen) Damm, P.F. Cannon & Crous [as 'limetticolum'], (2012)
Gloeosporium mangiferae Henn. 1898 accepted as Colletotrichum coccodes (Wallr.) S. Hughes, (1958)
Gloeosporium musarum Cooke & Massee 1887
Gloeosporium myricae Dippen. 1931
Gloeosporium olivarum J.V. Almeida 1899 accepted as Colletotrichum coccodes (Wallr.) S. Hughes, (1958)
Gloeosporium papayae Henn. 1895
Gloeosporium passiflorae Speg. 1898 accepted as Colletotrichum coccodes (Wallr.) S. Hughes, (1958)
Gloeosporium psidii Delacr. 1903 accepted as Colletotrichum coccodes (Wallr.) S. Hughes, (1958)
Gloeosporium ptychospermatis Henn. 1902 accepted as Phlyctema ptychospermatis (Henn.) Arx, (1957)
Gloeosporium sansevieriae Verwoerd & du Plessis 1931
Gloeosporium sclerocaryae Pole Evans*
Gloeosporium venetum Speg. 1879
Gloeosporium violae Berk. & Br. (sic) possibly Pass. 1849, accepted as Marssonina violae (Pass.) Magnus, (1906)
Gloeosporium sp.
Genus: Glomerella Spauld. & H. Schrenk 1903, accepted as Colletotrichum Corda, (1831)
Glomerella cingulata (G.F. Atk.) Spauld. & H. Schrenk 1903 accepted as Colletotrichum gloeosporioides (Penz.) Penz. & Sacc., (1884)
Glomerella glycines Lehman & F.A. Wolf 1926 accepted as Colletotrichum glycines Hori ex Hemmi, (1920)
Glomerella gossypii Edgerton 1909 accepted as Colletotrichum gossypii Southw., (1891)
Glomerella lindemuthiana Shear [as lindemuthianum], Bull. (1913) accepted as Colletotrichum lindemuthianum (Sacc. & Magnus) Briosi & Cavara 1889
Glomerella phacidiomorpha (Ces.) Petr. 1927
Glomerella psidii J. Sheld. 1905
Glomerella rufomaculans (Berk.) Spauld. & H. Schrenk 1903 accepted as Colletotrichum gloeosporioides (Penz.) Penz. & Sacc., (1884)
Genus: Gloniella Sacc. 1883
Gloniella multiseptata Doidge 1920 accepted as Gloniella natalensis Doidge, (1941)
Gloniella natalensis Doidge, 1941
Genus: Glyphis Ach. 1814 (Lichens)
Glyphis cicatricosa Ach. 1814
Glyphis cicatricosa var. confluens (Zenker) Zahlbr. 1927 accepted as Glyphis cicatricosa Ach. 1814
Glyphis cicatricosa var. simplicior (Vain.) Zahlbr. 1927
Glyphis confluens Zenker 1827 accepted as Glyphis cicatricosa Ach. 1814
Gn
Genus: Gnomonia Ces. & De Not. 1863
Gnomonia leptostyla (Fr.) Ces. & De Not. 1863
Family: Gnomoniaceae G. Winter 1886
Go
Genus: Gomphinaria Preuss 1851, accepted as Ramularia Unger, (1833)
Gomphinaria pedrosoi (Brumpt) C.W. Dodge 1935 accepted as Fonsecaea pedrosoi (Brumpt) Negroni, (1936)
Genus: Gorgoniceps (P. Karst.) P. Karst. 1871
Gorgoniceps kuitoensis Henn. 1903
Gr
Genus: Grammothele Berk. & M.A. Curtis 1868
Grammothele mappa Berk. & M.A. Curtis 1868 accepted as Grammothele lineata Berk. & M.A. Curtis, (1868)
Genus: Grandinia Fr. 1838 accepted as Hyphodontia J. Erikss., (1958)
Grandinia bicolor P.H.B. Talbot 1948 accepted as Dendrodontia bicolor (P.H.B. Talbot) Hjortstam & Ryvarden, (1980)
Grandinia rosea Henn. 1905 accepted as Roseograndinia rosea (Henn.) Hjortstam & Ryvarden, (2005)
Genus: Graphina Müll. Arg. 1880
Graphina acharii (Fée) Müll. Arg. 1887 accepted as Allographa acharii (Fée) Lücking & Kalb, (2018)
Graphina analoga (Nyl.) Zahlbr. 1927
Graphina atrofusca Müll. Arg. 1887 accepted as Glyphis atrofusca (Müll. Arg.) Lücking, (2009)
Graphina bylii (Vain.) Zahlbr. 1932
Graphina bylii var. lividula (Vain.) Zahlbr. 1932
Graphina obtrita (Fée) Müll. Arg. 1887
Graphina pergracilis Zahlbr. 1932
Graphina platycarpa (Eschw.) Zahlbr. 1902
Graphina polycarpa Müll. Arg. 1887
Graphina sophistica (Nyl.) Müll. Arg. 1880
Family: Graphiolaceae Clem. & Shear 1931
Genus: Graphiola Poit. 1824
Graphiola phoenicis (Moug. ex Fr.) Poit. 1824
Family: Graphidaceae Dumort. 1822 (Lichens)
Genus: Graphis Adans. 1763 (Lichens)
Graphis acharii Fée 1825 accepted as Allographa acharii (Fée) Lücking & Kalb, (2018)
Graphis analoga Nyl. 1859
Graphis analoga f. tetraspora Stizenb.*
Graphis atrofusca (Müll. Arg.) Stizenb. 1891
Graphis bylii Vain. 1926
Graphis bylii var. lividula Vain. 1926
Graphis caesiopruinosa (Fée) Kremp. 1875 accepted as Phaeographina caesiopruinosa (Fée) Müll. Arg., (1887)
Graphis cicatricosa (Ach.) Vain. 1890 accepted as Glyphis cicatricosa Ach., (1814)
Graphis cicatricosa var. confluens (Zenker) Vain. 1890 accepted as Glyphis cicatricosa Ach., (1814)
Graphis cicatricosa var. simplicior Vain. 1890
Graphis denudans Vain. 1926
Graphis devestiens Nyl. 1891
Graphis diaphoroides Müll. Arg. 1886
Graphis intertexta Nyl. (sic) possibly Müll. Arg. 1895
Graphis intricata Fée 1825
Graphis inusta var. emergens Vain. ex Van der Byl 1931
Graphis mesographa Nyl. 1863
Graphis polycarpa (Müll. Arg.) Stizenb. 1891
Graphis scripta (L.) Ach. 1809
Graphis sophistica Nyl. 1863
Graphis striatula (Ach.) Spreng. 1827 accepted as Allographa striatula (Ach.) Lücking & Kalb, (2018)
Graphis subfarinacea Nyl. 1891
Graphis subolivacea Zahlbr. 1926
Gu
Genus: Guepinia Fr. 1825
Guepinia agariciformis Lloyd 1923 accepted as Dacryopinax spathularia (Schwein.) G.W. Martin, (1948)
Guepinia fissa Berk. 1843
Guepinia flabellata Cooke 1884 accepted as Inflatostereum glabrum (Pat.) D.A. Reid, (1965)
Guepinia palmiceps Berk. 1843
Guepinia petaloides Kalchbr. 1882
Guepinia sparassoides Kalchbr. 1882
Guepinia spathularia (Schwein.) Fr. 1828 accepted as Dacryopinax spathularia (Schwein.) G.W. Martin, (1948)
Guepinia spathularia f. lata Lloyd.*
Genus: Guignardia Viala & Ravaz 1892, accepted as Phyllosticta Pers., (1818)
Guignardia bidwellii (Ellis) Viala & Ravaz 1892 accepted as Phyllosticta ampelicida (Engelm.) Aa, (1973)
Gy
Genus: Gyalecta Ach. 1808
Gyalecta thunbergiana Ach. 1810 accepted as Diploschistes thunbergianus (Ach.) Lumbsch & Vězda, (1993)
Family: Gyalectaceae Stizenb. 1862
Order: Gymnoascales G. Winter 1884
Family: Gymnoascaceae Imperfectae
Family: Gymnocarpeae
Genus: Gymnoglossum Massee 1891
Gymnoglossum radiatum (Lloyd) Bottomley 1948 accepted as Aroramyces radiatus (Lloyd) Castellano, Verbeken & Walleyn, (2000)
Genus: Gyrodon Opat. 1836
Gyrodon capensis Sacc. 1896
Family: Gyrophoraceae Zenker 1827
Genus: Gyrophragmium Mont. 1843
Gyrophragmium delilei Mont. 1843
Gyrophragmium inquinans (Berk.) Lloyd 1904
Genus: Gyrostomum Fr. 1825, accepted as Glyphis Ach., (1814) (Lichens)
Gyrostomum scyphuliferum (Ach.) Nyl. 1862 accepted as Glyphis scyphulifera (Ach.) Staiger, (2002)
See also
List of bacteria of South Africa
List of Oomycetes of South Africa
List of slime moulds of South Africa
List of fungi of South Africa
List of fungi of South Africa – A
List of fungi of South Africa – B
List of fungi of South Africa – C
List of fungi of South Africa – D
List of fungi of South Africa – E
List of fungi of South Africa – F
List of fungi of South Africa – G
List of fungi of South Africa – H
List of fungi of South Africa – I
List of fungi of South Africa – J
List of fungi of South Africa – K
List of fungi of South Africa – L
List of fungi of South Africa – M
List of fungi of South Africa – N
List of fungi of South Africa – O
List of fungi of South Africa – P
List of fungi of South Africa – Q
List of fungi of South Africa – R
List of fungi of South Africa – S
List of fungi of South Africa – T
List of fungi of South Africa – U
List of fungi of South Africa – V
List of fungi of South Africa – W
List of fungi of South Africa – X
List of fungi of South Africa – Y
List of fungi of South Africa – Z
References
Sources
Further reading
South African biodiversity lists
South Africa | List of fungi of South Africa – G | [
"Biology"
] | 5,424 | [
"Fungi",
"Lists of fungi"
] |
74,882,905 | https://en.wikipedia.org/wiki/John%20Stinchcombe | John R. Stinchcombe (born 1974) is an American and Canadian ecological geneticist who is a professor of ecology and evolutionary biology at the University of Toronto. His research is on the ecology of natural selection, and the role of genetics in facilitating or constraining evolution, focusing almost exclusively on plants.
Early life and education
Stinchcombe grew up in Syracuse, NY, USA, in an outdoors-loving family. He was an undergraduate at Bucknell University, graduating in 1996. He then spent a summer working for the National Marine Fisheries Service, in Washington, D.C., before starting his Ph.D. at Duke University in 1996. He started in the Zoology Department, and finished his PhD in 2001 in the Biology Department, with a Certificate in Ecology. His PhD research was on the evolution of resistance and tolerance to herbivory in the Ivyleaf morning glory (Ipomoea hederacea). Stinchcombe's post-doctoral work was at Brown University, working with Johanna Schmitt. His work there was on flowering time clines and genetics in mouse ear cress (Arabidopsis thaliana), as well as growth plasticity in touch-me-nots (Impatiens capensis).
Research and career
Stinchcombe started a faculty position at the University of Toronto in 2005, in the Botany Department, and joined the Department of Ecology and Evolutionary Biology at its creation.
Stinchcombe's research is on plant ecological genetics. Topics investigated by his lab include the genetics of flowering time, clines, phenotypic plasticity, plant-microbe interactions, natural selection in the field, evolution of gene expression, and the evolution of herbicide resistance.
Stinchcombe served as the Secretary for the Society for the Study of Evolution, and since 2013 he has been the Director of the Koffler Scientific Reserve, the University of Toronto's field research station.
Recent publications
From Google Scholar Profile
Harrison, T. L., Z. A. Parshuram, M. E. Frederickson, and J. R. Stinchcombe. 2024. Is there a latitudinal diversity gradient for symbiotic microbes? A case study with sensitive partridge peas. Molecular Ecology 33: e17191; doi: https://doi.org/10.1111/mec.17191
Henry, G. A., and J. R. Stinchcombe. 2023. G-matrix stability in clinally diverging populations of an annual weed. Evolution 77:49–62.
Kreiner, J. M., S. M. Latorre, H. A. Burbano, J. R. Stinchcombe, S. P. Otto, D. Weigel, and S. I. Wright. 2022. Rapid weed adaptation and range expansion in response to agriculture over the past two centuries. Science 378:1079–1085.
Kreiner, J. M., A. Caballero, S. I. Wright, and J. R. Stinchcombe. 2022. Selective ancestral sorting and de novo evolution in the agricultural invasion of Amaranthus tuberculatus. Evolution 76:70–85.
Gomulkiewicz, R., and J. R. Stinchcombe. 2022. Phenotypic plasticity made simple, but not too simple. Am. J. Bot. 109:1519–1524.
McGoey, B. V., and J. R. Stinchcombe. 2021. Introduced populations of ragweed show as much evolutionary potential as native populations. Evol. Appl. 14:1436–1449.
Honors
1995 Harry S. Truman Scholarship
2019 Distinguished Professor of Ecological Genetics, University of Toronto
2023 Natural Sciences Fellow, Swedish Collegium for Advanced Study
References
1974 births
Living people
Evolutionary biology
University of Toronto people
Bucknell University alumni
Duke University alumni | John Stinchcombe | [
"Biology"
] | 825 | [
"Evolutionary biology"
] |
74,883,274 | https://en.wikipedia.org/wiki/Muzzle%20reference%20system | A muzzle reference system (MRS) is a device used on most modern tank guns and some artillery systems that measures the bending of the barrel due to heat, gravity and other issues. It normally consists of a laser device and detector mounted at the breach end of the gun, often co-located with other optics like the gunner's sight, and a mirror at the muzzle. By measuring the deflection of the barrel, corrections can be applied by the ballistic computer to correct for changes as the gun is fired.
Static muzzle reference system (SMRS)
Dynamic muzzle reference system (DMRS)
See also
Thermal sleeve
References
External links
Ballistics | Muzzle reference system | [
"Physics"
] | 131 | [
"Applied and interdisciplinary physics",
"Ballistics"
] |
74,883,409 | https://en.wikipedia.org/wiki/List%20of%20gymnosperm%20families | The gymnosperms consist of five orders of seed plants: Cupressales, Cycadales, Ginkgoales, Gnetales and Pinales. They developed more than 350 million years ago, long before flowering plants, according to the fossil record. The name comes from the Greek for "naked seed"; the egg cells are not protected by ovaries, as in flowering plants.
Gymnosperms are divided into 12 families of trees, shrubs and woody vines. Sequoiadendron giganteum, the giant redwood, is the largest tree in the world, and Sequoia sempervirens, the coastal redwood, is the tallest. Ginkgo trees tolerate urban pollutants well, and are often planted in and near cities. The pine family is the main source of softwood timber, paper pulp and turpentine. The flexible wood of the yew family is used in longbows and musical instruments.
Glossary
From the glossary of botanical terms:
deciduous: falling seasonally, as with bark, leaves, or petals
unisexual: of one sex; bearing only male or only female reproductive organs
woody: hard and lignified; not herbaceous
Families
See also
List of plant family names with etymologies
Notes
Citations
References
See the Creative Commons license.
See their terms-of-use license.
Systematic
Gymnosperm
Gymnosperm families
gymnosperm families
Gymnosperms | List of gymnosperm families | [
"Biology"
] | 299 | [
"Lists of biota",
"Lists of plants",
"Gymnosperms",
"Plants"
] |
74,883,647 | https://en.wikipedia.org/wiki/Conley%20conjecture | The Conley conjecture, named after mathematician Charles Conley, is a mathematical conjecture in the field of symplectic geometry, a branch of differential geometry.
Background
Let be a compact symplectic manifold. A vector field on is called a Hamiltonian vector field if the 1-form is exact (i.e., equals to the differential of a function . A Hamiltonian diffeomorphism is the integration of a 1-parameter family of Hamiltonian vector fields .
In dynamical systems one would like to understand the distribution of fixed points or periodic points. A periodic point of a Hamiltonian diffeomorphism (of periodic ) is a point such that . A feature of Hamiltonian dynamics is that Hamiltonian diffeomorphisms tend to have infinitely many periodic points. Conley first made such a conjecture for the case that is a torus.
The Conley conjecture is false in many simple cases. For example, a rotation of a round sphere by an angle equal to an irrational multiple of , which is a Hamiltonian diffeomorphism, has only 2 geometrically different periodic points. On the other hand, it is proved for various types of symplectic manifolds.
History of studies
The Conley conjecture was proved by Franks and Handel for surfaces with positive genus. The case of higher dimensional torus was proved by Hingston. Hingston's proof inspired the proof of Ginzburg of the Conley conjecture for symplectically aspherical manifolds. Later Ginzburg--Gurel and Hein proved the Conley conjecture for manifolds whose first Chern class vanishes on spherical classes. Finally, Ginzburg--Gurel proved the Conley conjecture for negatively monotone symplectic manifolds.
References
Symplectic geometry
Conjectures | Conley conjecture | [
"Mathematics"
] | 369 | [
"Unsolved problems in mathematics",
"Mathematical problems",
"Conjectures"
] |
74,884,154 | https://en.wikipedia.org/wiki/Agrowth | Agrowth is a concept in economic policy according to which it is preferable to be indifferent to the growth of gross domestic product (GDP growth) when devising policies to further economic and societal progress. The reasoning behind agrowth is that GDP growth does not correlate closely with such progress.
The concept has been particularly discussed in the context of environmental policy, where it is opposed to both green growth and degrowth. Agrowth is supported by many scientists.
See also
Climate policy
Environmental economics
Eco-economic decoupling
Post-growth
Sustainability
References
Environmental social science concepts
Environmental economics | Agrowth | [
"Environmental_science"
] | 120 | [
"Environmental social science concepts",
"Environmental economics",
"Environmental social science"
] |
74,885,040 | https://en.wikipedia.org/wiki/Satellite%20imagery%20in%20North%20Korea | Satellite imagery in North Korea is a knowledge-building tool in the field of North Korean studies. It enables researchers to produce data-based analyses in the agricultural, humanitarian, economic and military fields, in a country where access to the field is limited.
Context
Collecting data on North Korea is very difficult. States generally produce reliable data, but in North Korea the data produced is often non-existent or of poor quality. When the North Korean government does produce data, its completeness and relevance are often called into question.
Access to the country is limited and satellite imagery is sometimes the only way to get an overview of important political or military locations.
History
Started in 1999 and emerging in 2012
High-resolution satellite imagery (1 metre and less) has been available since 1999, but its use for North Korean studies did not emerge until 2012. By 2004, researchers and NGOs had imaging and computing capabilities comparable to those available to the US government 20-30 years earlier, in the 1970s. Prior to 2012, imagery was largely focused on nuclear sites in North Korea, notably Yongbyon and Punggue-ri.
Satellite images with a resolution of less than one metre can be used to identify a wide range of objects such as buildings, forests, orchards, fields, fences, rivers, railways and roads.
At the same time as improving resolution, satellite images make spectral analysis accessible, beyond the visible light spectrum. SARs provide a 3D rendering of the earth, even in rainy weather or at night.
Obstacle to the acquisition of satellite images
The development of analyses based on satellite images has been hampered by a number of factors: the cost of acquiring these images, the decision by satellite imagery companies not to include images of the country in their public catalogues for political or technical reasons, or simply as a management decision.
Speeding up satellite image acquisition
The use of satellite imagery has been boosted by technological improvements, the expansion of the satellite imagery industry and public interest in North Korea, prompting satellite imagery companies to capture more frequently and highlight this product on their catalogues.
Difficulties of analysis and risks of misinformation
Despite the name "high-resolution image" the analysis of satellite images is hampered by the quality of the images available, leaving more or less room for interpretation as well as by the frequency of image capture. Analysis is dependent on the analysts' cultural, technical knowledge and experience of the specific country context. This is exacerbated for observation of North Korea's nuclear programme. To produce robust information satellite imagery must be cross-referenced with other data sources to understand long-term dynamics.
The growing competition in the field of North Korea studies and the resulting pressure on researchers to be the first to produce a scientific paper is a source of haste in the analysis. The analysis is constructed with less information. Over-extrapolation from satellite images can lead to major errors in analysis.
In a context of short, rapid media cycles, brief or incomplete analyses based on satellite imagery can lead to the dissemination of misinformation, even unintentionally.
The number of experts in the analysis of satellite imagery in North Korea is limited, but recognition algorithms can partially mitigate this problem.
North Korea's adaptation
North Korea is adapting to the high level of surveillance of its territory by satellite images, so the examination of any satellite image must take into account the possibility of concealment, camouflage or even deception by the North Koreans.
Usage
Economic
Analysis of satellite imagery creates knowledge based on new data to better understand activities in North Korea in areas where data acquisition is difficult, such as infrastructure development, construction projects, smuggling activities, etc.
Imagery via Google Earth of the country has enabled researcher Benjamin Katzeff to analyse markets in North Korea by their location their size and geographical distribution, and then approximate economic aggregates, such as reported taxes.
Imagery is used to observe regional and national development patterns and trends or to observe activities violating sanctions against North Korea such as fishing activities.
Agriculture
Satellite imagery is used to monitor agricultural and food production. Changes in weather conditions (flooding, drought, etc.) are tracked in agricultural areas to estimate harvest possibilities. Examination of areas hit by typhoons has enabled an analysis of the impact on harvests, enabling food needs to be assessed and humanitarian aid to be provided.
Humanitarian aid
Some NGOs use satellite images to study the progress of their project as they are not always on the ground.
Military
Nuclear and weapons of mass destruction
Analysis of satellite imagery allows us to understand the development of North Korea's nuclear arsenal by observing the infrastructure and activity of nuclear sites. This is sometimes the only way to observe North Korea's nuclear programme, as international and US experts are rarely admitted to the country's nuclear sites.
Human rights
Satellite imagery is very useful in the field of human rights in the country. The U.S. Committee for Human Rights in North Korea has published reports using satellite imagery and defector testimony to analyse the infrastructure and activity of prison camps, particularly to understand renovations, extensions or closures of these sites.
Satellite imagery producer
There are different types of imagery providers. They are military, governmental or commercial
Military
United States Government, through the National Reconnaissance Office (classified documents)
Government
Landsat (by the USGS)
European Union, with research programmes (Copernicus...)
Commercial
Maxar Technologies, formerly known as Digital Globe (0.3 m)
Airbus DS Geo (0.5 m)
ESRI
Planet Labs (imagery captured at daily frequency, 3m)
References
External links
Remote sensing
Geographic data and information
Science and technology in North Korea | Satellite imagery in North Korea | [
"Technology"
] | 1,119 | [
"Geographic data and information",
"Data"
] |
74,888,887 | https://en.wikipedia.org/wiki/WISEA%20J120037.79-784508.3 | WISEA J120037.79-784508.3, also called W1200-7845 or 2MASS J12003792-7845082, is a brown dwarf with a primordial disk 333.73 ± 3.13 lightyears from Earth in the 3.7 Myr-old ε Chamaeleontis (ε Cha) association, currently making it the closest known brown dwarf with an associated circumstellar disk. It was discovered by citizen scientists in 2020 volunteering for the Disk Detective project.
Disk Detective's science team then cross-matched W1200-7845 with BANYAN Σ, a Bayesian analysis tool used to estimate the likelihood that an object is a member of a young moving group based on its position, proper motion, parallax (using Gaia DR2 data, if available) and radial velocity. The analysis revealed (with 99.8% probability) that the brown dwarf was a member of the ε Cha young moving group association.
Brown dwarf
The brown dwarf has a mass of about 42–58 and has a spectral type of about M6.0γ. The gamma (γ) signifies the low surface gravity of the object, which is typical for young brown dwarfs. No accretion was detected from paschen and brackett spectral lines.
Later observations by Kubiak et al. 2021 found a strong H-alpha emission line, which indicates strong accretion of material. Named candidate #22 in their sample, it was the strongest accreting object in their entire sample.
Disk
Three possible scenarios were considered for the disk: i) A blackbody disk (a disk with uniform temperature), ii) two blackbody disks (a disk with a gap) and iii) a power-law disk.
The blackbody disk model has a temperature of 516 K (243°C; 469°F). The two-blackbodies model compromises of an inner disk with a temperature of 730 K (457°C; 854°F) and an outer disk with a temperature of 230 K (-43°C; -46°F). The best-fit model is a power-law disk with a power-law slope of α=-0.94, which is consistent with a class II disk. The close proximity of this system to the solar system makes this disk a good candidate to image the disk with ALMA.
See also
Backyard Worlds: Planet 9
Cha 110913−773444
Goddard Space Flight Center
Wide-field Infrared Survey Explorer
WISEA 1101+5400
References
External links
Disk Detective's Zooniverse blog at diskdetective.org
Citizen scientists spot closest young brown dwarf disk yet from MIT News
Brown dwarfs
Circumstellar disks
Chamaeleon
WISE objects
Astronomical objects discovered in 2020 | WISEA J120037.79-784508.3 | [
"Astronomy"
] | 587 | [
"Chamaeleon",
"Constellations"
] |
74,889,407 | https://en.wikipedia.org/wiki/Quantum%20Mechanics%20%28book%29 | Quantum Mechanics (), often called the Cohen-Tannoudji, is a series of standard ungraduate-level quantum mechanics textbook written originally in French by Nobel laureate in Physics Claude Cohen-Tannoudji, and Franck Laloë; in 1973. The first edition was published by Collection Enseignement des Sciences in Paris, and was translated to English by Wiley.
The book was originally divided into two volumes. A third volume was published in 2017.
The book structure is notable for having an extensive set of complementary chapters, introduced along with a "reader's guide", at the end of each main chapter.
Table of contents
Vol. 1
I. Waves and particles. Introduction to the ideas of quantum mechanics
II. Mathematical tools of quantum mechanics
III. The postulates of quantum mechanics
IV. Applications of the postulates to simple cases: Spin-1/2 and two-level systems
V. The one dimensional harmonic oscillator
VI. General properties of angular momentum in quantum mechanics
VII. Particle in a central potential: the hydrogen atom
Vol. 2
VIII An elementary approach to the quantum theory of scattering by a potential
IX. Electron spin
X. Addition of angular momenta
XI. Stationary perturbation theory
XII. An application of perturbation theory: The fine and hyperfine structure of the hydrogen atom
XIII. Approximation methods for time-dependent problems
XIV. Systems of identical particles
Appendices
Vol. 3
XV. Creation and annihilation operators for identical particles
XIV. Field operator
XVI. Paired states of identical particles
XVII. Review of classical electrodynamics
XIX. Quantization of electromagnetic radiation
XX. Absorption, emission and scattering of photons by atoms
XXI. Quantum entanglement, measurements, Bell's inequalities
Appendices
Reception
Bernd Crasemann writing for the American Journal of Physics praised the book for its clarity and its unusual structure that introduces the reader to intermediate topics. According to him, the "gems" of the book are the complements related to atomic, molecular, and optical physics; condensed matter physics and nuclear physics. The book has also been suggested as a complement to simplified introductory books in quantum mechanics.
Experimental physicist and 2022 Nobel laureate in Physics Alain Aspect, has frequently mentioned that the book was a revelation early in his career, helping him better understand the research papers of quantum mechanics and the work of John Stewart Bell.
See also
Introduction to Quantum Mechanics, an undergraduate text by David J. Griffiths
Modern Quantum Mechanics undergraduate book by J. J. Sakurai
List of textbooks on classical mechanics and quantum mechanics
References
Physics textbooks
1985 non-fiction books
1994 non-fiction books
2020 non-fiction books
Quantum mechanics | Quantum Mechanics (book) | [
"Physics"
] | 544 | [
"Quantum mechanics",
"Works about quantum mechanics"
] |
74,890,648 | https://en.wikipedia.org/wiki/Pathogenic%20microorganisms%20in%20frozen%20environments | On Earth, frozen environments such as permafrost and glaciers are known for their ability to preserve items, as they are too cold for ordinary decomposition to take place. This makes them a valuable source of archeological artefacts and prehistoric fossils, yet it also means that there are certain risks once ancient organic matter is finally subject to thaw. The best-studied risk is that of decomposition of such organic matter releasing a substantial quantity of carbon dioxide and methane, and thus acting as a notable climate change feedback. Yet, some scientists have also raised concerns about the possibility that some metabolically dormant bacteria and protists, as well as always metabolically inactive viruses, may both survive the thaw and either threaten humans directly, or affect some of the animal or plant species important for human wellbeing.
As of 2023, there has been at least one recorded reemergence of anthrax, a pathogen long-known for its ability to hibernate in soils. There have also been several cases when truly novel microorganisms discovered in the frozen environments were successfully revived by researchers, or were found live in a recently thawed environment. So far, most only affect amoebas, and none have been known to pose a risk to humans or to crops. Of the already-studied pathogens, at least one anthrax outbreak has been connected to decades-old infected carrion thaw; yet, samples of influenza and smallpox pathogens have failed to survive the thaw even in laboratory conditions. Some researchers have also raised alarm about the potential of horizontal gene transfer between ancient and modern bacteria, and the risk it could exacerbate the challenge of antibiotic resistance. At the same time, other scientists consider these concerns overblown, and argue that ancient microorganisms are unlikely to make a difference today.
Timeline of research into the subject
20th century
Johan Hultin made multiple attempts during the 20th century to culture 1918 influenza virus he found in the frozen corpses of pandemic victims at Brevig Mission in Alaska. Every attempt failed, which suggested that the influenza virus is incapable of surviving the thaw after being frozen. In the 1990s, other scientists have tried to revive pneumonia-causing bacteria and the smallpox virus, yet all of those attempts were unsuccessful as well.
1999
A group of researchers was able to extract potentially viable microscopic fungi, as well as the RNA of tomato mosaic virus, from Greenland ice cores up to 140,000 years old.
2004
It was estimated that between 1017 and 1021 microorganisms, ranging from fungi and bacteria in addition to viruses, were already released every year due to ice melt, often directly into the ocean. According to researchers behind this estimate, only viruses with high abundance, ability to be transported through ice, and ability to resume disease cycles after the thaw would be of any concern.
In particular, caliciviruses of Vesivirus genus were hypothesized as the most likely to spread from ancient ice, due to their high abundance and using ocean animals as hosts, where the migratory nature of many species of fish and birds could potentially enable a high transmission rate. Caliciviruses are poorly adapted to humans, and the only known infections were of marine biologists who worked closely with infected seals. However, Enteroviruses (a group which includes polioviruses, echoviruses and Coxsackie viruses) and even influenza A were also considered less likely but still plausible candidates.
2005
In the 1960s, the United States Army Corps of Engineers had dug out Fox tunnel in Alaska, to provide a good test ground to better understand permafrost before the construction of the Trans-Alaska Pipeline System. By 2005, scientists revisiting that tunnel have discovered frozen cells of carnobacterium pleistocenium, with an estimated age of 32,000 years. Melting the ice had revived them, resulting in the first documented case of an organism "coming back to life" from ancient ice. None of the bacteria in carnobacterium genus are known to be pathogenic in humans, although some are known for spoiling chilled food products, and one species may cause disease in fish.
2011
A paper by two Russian scientists in Global Health Action, a journal published by Umeå University in Sweden, had warned of the risk that the old burial grounds of cattle which had died to anthrax in the early last century may thaw and lead to the re-emergence of the viable pathogen. The authors noted that at the time, there were about 13,885 cattle burial grounds in Northern Russia, a substantial fraction of which did not meet sanitary standards, and some had their maps or other records missing.
2014
A completely unknown plant virus was revived from a frozen caribou feces deposit which was only 700 years old. It was named "ancient caribou feces associated virus" (aCFV) by its discoverers. The scientists have also introduced this virus into the tissues of Nicotiana benthamiana, a common model species for plant pathogens. aCFV had successfully replicated, yet was unable to cause more than an asymptomatic infection. According to the researchers, this either suggests a large genetic distance between the original host species of aCFV and more modern plants, or that N. benthamiana was simply a suboptimal host for this species.
Also in 2014, two ~30,000 years old giant virus species, Pithovirus sibericum and Mollivirus sibericum, were discovered in the Siberian permafrost and they retained their infectivity. Like the other giant viruses with large genomes, they are larger in size than most bacteria and pose no risk to humans, as they infect other microorganisms like Acanthamoeba, a genus of amoebas.
2016
An anthrax outbreak had occurred in the Yamal Peninsula region in Northern Russia. It was thought to be linked to an infected reindeer corpse, which died 75 years earlier, yet had thawed after a heatwave. Over 2,000 reindeer had been infected and the disease had spread to humans, hospitalizing dozens and killing a child before the outbreak was contained.
2023
The same team of French researchers behind the 2014 revival of two giant viruses had also managed to revive 8 more ancient amoeba-infecting viral species. Four of these species were from the pandoravirus, cedratvirus (sometimes classified as a subgroup of pithovirus), megavirus and pacmanvirus (part of Asfarviridae) families, which weren't previously revived from the permafrost. In addition, five more species from these families were found in already thawed permafrost, with no way to tell their age. The oldest revived virus was a 48,500-year-old Pandoravirus yedoma.
Current scientific understanding
Scientists are split on whether revived microorganisms from the permafrost can pose a significant threat to humans. Jean-Michel Claverie, who led the most successful attempts to revive such "zombie viruses", believes that the public health threat from them is underestimated, and that while his research focused on amoeba-infecting viruses, this decision was in part motivated by the desire to avoid viral spillover as well as convenience, and "one can reasonably infer" other viral species would also remain infectious. Another professor, Birgitta Evengård, argued that permafrost thaw would eventually uncover microorganisms older than the human species, and to which there would be no preexisting immunity. In the same interview, Claverie had even suggested that ancient microorganisms might have had caused or contributed to the extinction of Neanderthals or mammoths, and that those may still be preserved in the permafrost. On the other hand, University of British Columbia virologist Curtis Suttle argued that "people already inhale thousands of viruses every day, and swallow billions whenever they swim in the sea". In his view, the odds of a frozen virus replicating and then circulating to a sufficient extent to threaten humans "stretches scientific rationality to the breaking point".
While some point to the 2016 Yamal Peninsula outbreak as an example of dangers associated with the thaw, others argue that anthrax is not a pathogen which can spread contagiously between humans, and that it has been known for its ability to remain dormant in the soil since the Middle Ages, without requiring the cold to do so. Some scientists have argued that Hultin's inability to revive thawed influenza virus, as well as other researchers' failure to revive pneumonia-causing bacteria or smallpox viruses show that pathogens adapted to warm-blooded hosts cannot survive being frozen for a prolonged period of time. However, many of the amoeba-infecting viruses revived in Claverie's 2023 research were taken from a ~27,000-year-old site with "a large amount of mammoth wool", and one species, Pacmanvirus lupus, was found in the intestine of an equally old Siberian wolf carcass.
There is some agreement that revived bacteria would be less dangerous than the revived viruses, since they would still be affected by broad-spectrum antibiotics and would not require wholly new treatments. However, they would not be completely vulnerable either, due to the discovery of ancient antibiotic resistance genes in permafrost samples. Antibiotics to which permafrost bacteria have displayed at least some resistance include chloramphenicol, streptomycin, kanamycin, gentamicin, tetracycline, spectinomycin and neomycin. Some scientists consider horizontal gene transfer of novel antibiotic resistance sequences from otherwise harmless ancient bacteria into modern pathogens to be a far more realistic threat than a revival of an ancient pathogen. At the same time, other studies show that resistance levels in ancient bacteria to modern antibiotics remain lower than in the contemporary bacteria from the active (thawed) layer above them, suggesting that this risk is "no greater" than in any other soil.
According to a 2023 interview with Marion Koopmans, the head of the Netherlands' Versatile Emerging infectious disease Observatory (VEO), precautions taken by the researchers studying potentially risky sites in Greenland include not starting new digs and only analyizing the locations which were already going to be studied by archeologists, wearing protective gear while in the field, and operating under high BSL standards in the lab. If a place was found to harbour a potentially dangerous microorganism, they have the authority to advise the Naalakkersuisut to shut down access to the area.
See also
Psychrophile
Antibiotic resistance
References
Epidemiology
Microorganisms
Permafrost | Pathogenic microorganisms in frozen environments | [
"Biology",
"Environmental_science"
] | 2,213 | [
"Epidemiology",
"Microorganisms",
"Environmental social science"
] |
74,890,981 | https://en.wikipedia.org/wiki/Kreiss%20matrix%20theorem | In matrix analysis, Kreiss matrix theorem relates the so-called Kreiss constant of a matrix with the power iterates of this matrix. It was originally introduced by Heinz-Otto Kreiss to analyze the stability of finite difference methods for partial difference equations.
Kreiss constant of a matrix
Given a matrix A, the Kreiss constant 𝒦(A) (with respect to the closed unit circle) of A is defined as
while the Kreiss constant 𝒦(A) with respect to the left-half plane is given by
Properties
For any matrix A, one has that 𝒦(A) ≥ 1 and 𝒦(A) ≥ 1. In particular, 𝒦(A) (resp. 𝒦(A)) are finite only if the matrix A is Schur stable (resp. Hurwitz stable).
Kreiss constant can be interpreted as a measure of normality of a matrix. In particular, for normal matrices A with spectral radius less than 1, one has that 𝒦(A) = 1. Similarly, for normal matrices A that are Hurwitz stable, 𝒦(A) = 1.
𝒦(A) and 𝒦(A) have alternative definitions through the pseudospectrum Λ(A):
, where p(A) = max{|λ| : λ ∈ Λ(A)},
, where α(A) = max{Re|λ| : λ ∈ Λ(A)}.
𝒦(A) can be computed through robust control methods.
Statement of Kreiss matrix theorem
Let A be a square matrix of order n and e be the Euler's number. The modern and sharp version of Kreiss matrix theorem states that the inequality below is tight
and it follows from the application of Spijker's lemma.
There also exists an analogous result in terms of the Kreiss constant with respect to the left-half plane and the matrix exponential:
Consequences and applications
The value (respectively, ) can be interpreted as the maximum transient growth of the discrete-time system (respectively, continuous-time system ).
Thus, the Kreiss matrix theorem gives both upper and lower bounds on the transient behavior of the system with dynamics given by the matrix A: a large (and finite) Kreiss constant indicates that the system will have an accentuated transient phase before decaying to zero.
References
Numerical linear algebra
Spectral theory
Systems theory | Kreiss matrix theorem | [
"Mathematics"
] | 494 | [
"Theorems in algebra",
"Theorems in linear algebra"
] |
74,890,992 | https://en.wikipedia.org/wiki/Triiron%20ditin%20intermetallic | The compound with empirical formula Fe3Sn2 is the first known kagome magnet. It is an intermetallic compound composed of iron (Fe) and tin (Sn), with alternating planes of Fe3Sn and Sn.
Preparation
The iron-tin intermetallic forms at around and naturally assumes a kagome structure. Quenching in an ice bath then cools the material to room temperature without disrupting the atomic structure.
Electronic structure
The compound's band structure exhibits a double Dirac cone, enabling Dirac fermions. A 30 meV gap separates the cones, which indicates the quantum Hall effect and massive Dirac fermions. Close measurement of the Fermi surface via the de Haas-van Alphen effect suggests that the massive fermions also exhibit Kane-Mele-type spin-orbit coupling.
Fe3Sn2 can also host magnetic skyrmions, but these typically require high magnetic fields to nucleate. For samples with a small (but nonzero) thickness gradient, only a small-amplitude (5-10 mT), direction-variant magnetic field suffices to nucleate the quasiparticles.
References
Intermetallics
Ferrous alloys
Tin alloys
2018 in science | Triiron ditin intermetallic | [
"Physics",
"Chemistry",
"Materials_science"
] | 262 | [
"Ferrous alloys",
"Inorganic compounds",
"Metallurgy",
"Tin alloys",
"Alloys",
"Intermetallics",
"Condensed matter physics"
] |
74,891,676 | https://en.wikipedia.org/wiki/Buellia%20frigida | Buellia frigida is a species of saxicolous (rock-dwelling), crustose lichen in the family Caliciaceae. It was first described from samples collected from the British National Antarctic Expedition of 1901–1904. It is endemic to maritime and continental Antarctica, where it is common and widespread, at altitudes up to about . The characteristic appearance of this lichen features shades of grey and black divided into small polygonal patterns. The crusts can generally grow up to in diameter (smaller sizes are more common), although neighbouring individuals may coalesce to form larger crusts. One of the defining characteristics of the lichen is a textured surface with deep cracks, creating the appearance of radiating . These lobes, bordered by shallower fissures, give the lichen a distinctive appearance and textured surface.
In addition to its striking appearance, Buellia frigida shows adaptability to the harsh Antarctic climate conditions. The lichen has an extremely slow growth rate, estimated to be less than per century. Because of its ability to not only endure but to thrive in one of the Earth's coldest, harshest environments, Buellia frigida has been used as a model organism in astrobiology research. This lichen has been exposed to conditions simulating those encountered in space and on celestial bodies like Mars, including vacuum, ultraviolet radiation, and extreme dryness. B. frigida has demonstrated resilience to these space-related stressors, making it a candidate for studying how life can adapt to and potentially survive in the extreme environments found beyond Earth.
Taxonomy
The lichen was described in 1910 by the British botanist Otto Darbishire. The type specimen was collected by Reginald Koettlitz in 1902 from Granite Harbour in McMurdo Sound growing on tuff. The samples were obtained as part of the British National Antarctic Expedition of 1901–1904. The of the lichen was as follows (translated from Latin): Darbishire observed that the newly described species appeared to belong to the genus Buellia. However, he noted that in its early stages of development, the apothecium sometimes had characteristics, sharing features with genus Rinodina. He noted that the , a specific layer of tissue in the lichen's apothecium, was often (blackened), particularly near the edges of the apothecium. Darbishire acknowledged the close relationship between the genera Buellia and Rinodina. In 1948, Carroll William Dodge proposed to transfer the taxon to genus Rinodina; however, the name Rinodina frigida was not validly published by Dodge. Later, in 1973, Dodge placed the taxon in genus Beltraminia as Beltraminia frigida in his work Lichen Flora of the Antarctic Continent and Adjacent Islands. The genus Beltraminia has since been synonymised with Dimelaena. In her 1968 monograph on Antarctic lichens, Elke Mackenzie supported Darbishire's placement in Buellia, largely because of the structure of the mature apothecia, wherein the disc lacks a .
Darbishire also simultaneously described Buellia quercina, collected at the same type locality as B. frigidia, but with a more margin and lighter colour. MacKenzie rejected taxonomic value for variations in the black, grey, and whitish colours of the thallus due to anatomical variations of the lichen, and reduced B. quercina to synonymy.
A 2016 molecular phylogenetics study of the Caliciaceae included B. frigida in its analysis. In the constructed phylogenetic tree, this species appeared as sister (closest evolutionary relative) to Amandinea coniops; the clade containing these two species was itself sister to Amandinea punctata; a similar result was obtained in a molecular analysis published in 2023. It is known that the genus Buellia itself is not monophyletic (derived from a single common ancestor).
Description
Buellia frigida is a crustose lichen (sometimes ) with a variable thallus size, more or less circular in outline. It has a diameter of up to , although it is often much smaller. The thallus is characterised by a black that extends approximately beyond the older central region of thallus; this black area represents the growth zone. In some instances, neighbouring thalli coalesce to form larger aggregations of up to . Its margin is somewhat , sometimes barely visible, and its older, central thallus has a deeply appearance, giving rise to the impression of radiating marginal . These lobes are further defined by shallower cracks, creating a surface divided into polygonal . The areoles have a somewhat cerebriform (brainlike) texture and can vary in colour from grey to black, with the tips of the marginal lobes typically appearing black. An amorphous layer, approximately 35–40 μm thick, covers the thallus. This layer, mucilaginous in nature, may appear white when it is dry.
The upper of B. frigida is about 6–7 μm thick. It has a rounded or swollen top () and grows in a dense, upright, and parallel arrangement (). However, it appears as a single layer of dark, thick-walled cells that are equal in diameter in all dimensions (). The within the thallus varies in thickness, containing cells of Trebouxia measuring between 4–7 μm in diameter. The medulla, composed of loosely woven, thin-walled hyphae that are somewhat vertically arranged, also has variability in thickness. The medulla stabilises the thallus structure and helps regulate water retention and gas exchange in the lichen. Beneath the medulla, there is a basal layer, approximately 15 μm thick, of compact dark brown cells that elongate upward and merge with the medullary hyphae. Medullary hyphae also help the thallus adhere tightly to the .
Buellia frigida forms black, slightly shiny apothecia, which are often more or less sessile on the older areoles. The apothecia start as flat but become convex as they mature. When young, they have a appearance; when mature they are in form, and up to about 1 mm in diameter. The amphithecial cortex is about 15–17 μm thick, formed by a of isodiametric cells. Algae that initially exist between the medullary hyphae disappear as the apothecia age. The medulla of the apothecia consists of vertical brown hyphae that are loosely woven and connected to the thalline medulla. The is not differentiated in older apothecia; instead, the amphithecial cortex darkens, and the medullary hyphae shrink together after the algae disappear, creating the impression of a dimidiate proper margin (i.e. divided into two equal or nearly equal halves). The hypothecium is brownish, with a thickness ranging from 30 to 80 μm in the centre and thinning towards the margin, where it merges with the amphithecial cortex. The ascus, which contains the ascospores, stands approximately 90–110 μm tall. Paraphyses, measuring 2 μm in diameter, darken above the asci and have an internal partition, or septum. The asci are , with dimensions of 36–46 by 14.5–17 μm, and contain dark brown, bilocular ascospores (divided into two segments by a septum). These ascospores are occasionally only slightly constricted at the septum, and some may remain unilocular. They are typically ellipsoid, with dimensions of 9–13 by 5–8 μm.
Asexual propagules, such as isidia or soredia, are not made by Buellia frigida. The lichen, however, does create pycnidia that originate from under the algal layer, appearing (with a rounded or bulbous form with a narrower portion or neck) to irregular and reaching sizes of up to 300 μm in diameter. A thin , consisting of very small-celled , surrounds the pycnidia. have a few septa and are branched at the base, measuring approximately 10 by 1 μm. The terminal are ellipsoid, measuring about 4 by 1 μm in size.
Similar species
Buellia subfrigida, described in 1993 and found in the Lützow-Holm Bay area and the Prince Olav Coast of East Antarctica, is closely related to Buellia frigida. Both species are part of a ((a closely related duo differing in key traits)), with B. subfrigida likely evolving from the sexually reproducing B. frigida through the acquisition of soredia. The species share morphological and chemical traits, forming circular thalli with distinct effigurate lobes at their margins, and have similar chemical profiles. However, B. subfrigida differs by its sorediate thallus. This adaptation allows B. subfrigida to grow in habitats that are seasonally inundated with water, a niche where B. frigida, despite its wide ecological amplitude (the limits of environmental conditions within which an organism can live and function), is rarely observed.
Habitat, distribution, and ecology
Buellia frigida is endemic to the maritime and continental Antarctic, growing in ice-free areas on exposed rock surfaces. On these surfaces, it prefers sheltered areas like crevasses or drainage channels. In crevasses, thalli chains grow larger near the ground. In its habitat, Buellia frigida is often the only species that colonises smooth, ice-polished rock. Once its thallus is about or more in diameter, Pseudephebe minuscula or Usnea sphacelata often begin growing near its centre. This secondary lichen growth degrades underlying B. frigida, leaving outer rings of healthy crustose lichen. The umbilicate lichen Umbilicaria decussata is another species that grows on Buellia frigida. Buellia frigida associates with different species across habitats. Near Syowa Station, a small community of Buellia frigida and Rhizocarpon flavum grows on slopes without nesting colonies of petrels and other birds. The nitrogen-enriched areas beneath bird nests have a more diverse lichen community, which, in addition to B. frigida, includes species from the genera Caloplaca, Umbilicaria, and Xanthoria. Phaeosporobolus usneae is a lichenicolous (lichen-dwelling) fungus that parasitises the thalli of B. frigida in Bunger Hills (Wilkes Land). Despite genetic evidence suggesting limited dispersal capabilities, B. frigida shows remarkable symbiotic flexibility, being able to associate with up to 13 different – one of the highest numbers recorded among Antarctic lichens.
Buellia frigida is among the most common lichens in Antarctica, particularly in eastern regions. The distribution of B. frigida extends throughout Antarctica, from the Peninsula to rocky coastal areas and exposed rock formations in the interior. It is one of about 25 lichen species that occur circumpolar in coastal areas and extend inland to nunataks and mountains near the South Pole. It is the most widespread lichen in east Antarctica, including the Larsemann Hills, but it is somewhat rare in Marie Byrd Land and the King Edward VII Land, increasing in Victoria Land and most common on Antarctica's eastern coast. It is most abundant in Victoria Land's dry valley region and higher elevations above , known for cloud cover and summer snow. The lichen has been found at altitudes of up to . About marks the altitudinal limit at which lichens can survive in the Antarctic. Above this height, the long periods of exposure to winter temperatures and the lack of insulating snow cover on windblown rock faces is too harsh to support lichen life.
The species typically forms communities in wind-protected areas, particularly in rock cracks and on the leeward side of rocks. These communities can consist of B. frigida alone or occur with other saxicolous lichens such as Lecidea cancriformis, Acarospora gwynnii, Carbonea vorticosa, Pseudephebe minuscula, Physcia caesia, and Lecidella siplei. On the less lichen-populated Antarctic Peninsula, it is confined to the western part, south of 67°S latitude. Collections of Buellia frigida are typically made in coastal areas, and its inland range in the continent's interior remains unknown. It is one of 20 species of Buellia that occur in Antarctica.
Physiological adaptations and growth
This lichen experiences high fluxes of photosynthetically active radiation, desiccation, and cold temperatures. The Net Assimilation Rate (NAR) measures how organisms convert light and carbon dioxide into organic substances through photosynthesis, minus respiration. Buellia frigidas maximum NAR occurs at with full thallus hydratation, showing its photosynthetic efficiency in polar ecosystems. Buellia frigida tolerates the harsh conditions of Antarctica. Its dark colouration is the result of pigmentation that protects it from harmful ultraviolet radiation, which is even greater at high latitudes and altitudes. Hydration swells the lichen thallus, which reduces the density of its black pigmentation in the cortex. This exposes the algal layer to light, enabling photosynthesis. When dry, the thallus shrinks, increasing the density of its pigmentation and shielding itself from light; this effect is most prevalent in the marginal areas, which contain the most algae. In situ measurements of this lichen's photosynthetic activity were conducted in continental Antarctica, showing it thrives in its habitat. Its high photosynthetic rate indicates adaptation to Antarctica's extreme conditions like low temperatures and intense light. This adaptability enables its survival in this region, where it is exposed to fluctuating moisture levels due to drying cycles of meltwater-soaked thalli. The photobiont partner of Buellia frigida has a higher cold resistance potential and a longer retention of photosynthetic capacity during exposure to freezing temperatures than the counterpart photobiont of several other Antarctic and European lichens.
Moisture availability determines Buellia frigidas distribution. At Cape Geology, southern Victoria Land, it primarily relies on meltwater from snowpack and occasional snowfalls for moisture in early summer. Despite the strong sunlight, the lichen survives in the combination of hydration, low temperatures, and intense light exposure. The distribution of lichen thalli on rock surfaces is influenced by the frequency and duration of meltwater moistening, reflecting its need for moisture.
Studies in continental Antarctica show the extremely slow radial growth rates of Buellia frigida. A monitoring study conducted in Yukidori Valley, no measurable increase in size was noted for any of the measured thalli after a five-year period. In the McMurdo Dry Valleys, the lichen growth rates varied across different sites, indicating responses to regional climate changes, including alterations in snowfall patterns. This adaptation over time demonstrates the lichen's resilience to changing environmental conditions in Antarctica, suggesting its use as an indicator of climate change in the region. Geographic information system technology has been used to detect subtle changes in the growth of Buellia frigida over a 42-year period. At radial growth rates of 0.0036 mm per year—about the thickness of an individual fungal hypha—some thalli are estimated to be at least 6,500 years old, dating back to the end of the Stone Age.
Studies on the population genetics of Buellia frigida indicate limited dispersal among regions in Antarctica, likely influenced by prevailing wind patterns and physical barriers such as glaciers. While the spores of B. frigida have the potential for wind-assisted dispersal, the lichen predominantly colonises specific areas conducive to its growth, particularly those with sufficient moisture during the short Antarctic summer, showing how environmental factors affect its dispersal. Samples of B. frigida collected from eastern Antarctica's Vestfold Hills and Mawson Station revealed minimal genetic variation: only three genotypes in the Vestfold Hills, differing by a single nucleotide. The most common genotype of B. frigida there matched specimens from Mawson Station, showing low genetic diversity across this large Antarctic region.
In astrobiology research
Buellia frigida is a model organism in astrobiology that provides insight into life's adaptability beyond Earth and the potential for survival in space. Research examines this extremotolerant species' endurance under harsh conditions akin to those in space and Mars. B. frigida resists non-terrestrial abiotic factors, including space exposure, hypervelocity impacts, and Mars-simulated conditions, which helps explain the biological responses to extreme environments.
Tests expose B. frigida to stressors like vacuum, UV radiation, and desiccation to measure its viability and photosynthetic activity. These tests reveal that B. frigida maintains high post-exposure viability and sustains minimal damage to its photosynthetic capacity under these conditions. This resilience stems from protective mechanisms including morphological traits, secondary compounds, and anhydrobiosis during desiccation, features that also enable other extremotolerant lichens to survive.
Space experiments on the International Space Station (ISS) and in simulated Mars conditions tested the lichen's survival. One study showed that exposure to low Earth orbit conditions resulted in reduced viability of its fungal and algal components, but the fungal partner was less affected than the algal partner. Despite this, the lichen maintained its structure, showing resilience to an extraterrestrial environment. This indicated potential adaptation of this terrestrial organism to space conditions.
Different results came from the European Space Agency's Biology and Mars Experiment (BIOMEX) project, also conducted on the ISS. These experiments showed high mortality rates for both algal and fungal symbionts of B. frigida under similar low Earth orbit conditions, suggesting reduced survival potential in extreme extraterrestrial environments, questioning whether Mars could support this lichen. In additional BIOMEX studies, researchers examined the DNA integrity of B. frigida over 1.5 years. They used the Randomly Amplified Polymorphic DNA technique and observed DNA alterations in space-exposed lichen compared to Earth-based controls, indicating limited resistance of Buellia frigida to the conditions of space and Mars-like environments.
See also
List of Buellia species
Notes
References
Cited literature
frigida
Lichen species
Lichens described in 1910
Taxa named by Otto Vernon Darbishire
Lichens of Antarctica
Extremophiles
Space-flown life
Fungal models | Buellia frigida | [
"Biology",
"Environmental_science"
] | 3,947 | [
"Space-flown life",
"Organisms by adaptation",
"Model organisms",
"Extremophiles",
"Bacteria",
"Environmental microbiology",
"Fungal models"
] |
74,891,951 | https://en.wikipedia.org/wiki/Indolizidine%20alkaloids | Indolizidine alkaloids are natural products from various alkaloid groups whose structure can be derived from indolizidine.
Occurrence
Indolizidine alkaloids are present in various plant families, including Elaeocarpaceae, Asclepiadaceae, and are also produced as metabolites by fungi and bacteria. For instance, Slaframine and swainsonine were identified in the fungus Rhizoctonia leguminicola, while Castanospermine was extracted from Castanospermum australe. Notably, this alkaloid group includes pumiliotoxins, which are the toxins of the strawberry poison-dart frog.
Representatives
Polyhydroxy alkaloids
The polyhydroxy alkaloids include compounds like castanospermine and swainsonine.
Pumiliotoxins
The primary alkaloids within the pumiliotoxin category are pumiliotoxin A and pumiliotoxin B. Other representatives include gephyrotoxin 223 AB and gephyrotoxin.
Phenanthroindolizidine alkaloids
Representatives of this alkaloid group include tylophorine, tylocrebrine and tylophorinidine.
Elaeocarpus alkaloids
Representatives of this group include Elaeocanine A, Elaeocarpine and Elaeocarpidine.
Securinega alkaloids
The main alkaloid in this category is securinine. Others are securinol A and norsecurinine.
Tylophora alkaloids
Most of the Tylophora alkaloids belong to the phenanthroindolizidine alkaloid family, including tylophorine, septicin, and hispidine.
Ipomoea alkaloids
Main alkaloids of this group are Ipalbin and Ipomin. Furthermore, Ipalbidine and Ipohardine occur.
Properties
Swainsonine-type compounds are currently under investigation for their potential as active agents against AIDS. Swainsonine and castanospermine function as inhibitors of sugar-splitting enzymes. Castanospermine also exhibits anti-cancer and anti-HIV properties, while Slaframine acts as a parasympathomimetic agent. Pumiliotoxin A enhances the contraction of striated muscle, and gephyrotoxin has similar effects to pumiliotoxin A. Due to their multifaceted impacts on the nervous system, these alkaloids are in high demand. However, their natural availability through frog skin extraction is severely limited due to species protection measures.
References
Alkaloids
Indolizidine alkaloids | Indolizidine alkaloids | [
"Chemistry"
] | 563 | [
"Organic compounds",
"Biomolecules by chemical classification",
"Natural products",
"Alkaloids"
] |
74,891,954 | https://en.wikipedia.org/wiki/Imidazole%20alkaloids | Imidazole alkaloids are a group of alkaloids whose basic structure contains the imidazole ring system.
Occurrence
In nature, imidazole alkaloids are found both as secondary plant compounds and as byproducts of histidine metabolism in marine organisms. One well-known imidazole alkaloid is pilocarpine, which is present in the leaves of Paraguay jaborandi.
For instance, from the seeds of garden cress (Lepidium sativum), various monomeric imidazole alkaloids can be isolated, including semilepidinoside A and semilepidinoside B, as well as dimeric forms such as lepidins B, C, D, E, and F. In the sponge Leucetta chagosensis, a variety of imidazole alkaloids, such as 2-deoxy-2-aminokealiiquinone and Naamine C, have been identified. Imbricatin has been isolated from the starfish Dermasterias imbricata, while martensin A has been obtained from the red alga Martensia fragilis. Notably, the marine sponge Pseudaxinyssa contains odilin.
The Maca plant contains relevant amounts of lepidilin.
Representative
A well-known imidazole alkaloid is pilocarpine. Other representatives include. cynodin, cynometrin and odilin.
Websites
Imidazole Alkaloids. In Encyclopedia of Biochemistry, at spektrum.de. Retrieved September 29, 2019.
References
Alkaloids
Imidazoles | Imidazole alkaloids | [
"Chemistry"
] | 343 | [
"Organic compounds",
"Biomolecules by chemical classification",
"Natural products",
"Alkaloids"
] |
74,892,559 | https://en.wikipedia.org/wiki/Master%20of%20Applied%20Ethics | A Master of Applied Ethics () is the only professional master's degree in philosophy conferred by Chinese universities. This program aims to integrate traditional philosophical teachings with the pressing ethical issues emerging in the modern world. The degree is primarily structured to offer specialized knowledge in various sectors, and its curriculum incorporates interdisciplinary approaches to address ethical concerns in technology, life sciences, artificial intelligence, big data, and business.
Overview
The Master of Applied Ethics program aims to train students to have an ethical theoretical foundation, combined with practical application skills in various professional fields. Graduates of this program are expected to possess the ability to discern ethical challenges, make moral judgments, and contribute to policy analysis and governance. The curriculum is designed to be interdisciplinary and is rooted in both traditional philosophical ethics and contemporary applied ethics.
Concentrations
The Master of Applied Ethics program offers various concentrations, including:
Technology ethics
This concentration focuses on the ethical implications of emerging technologies and their integration into society. Students delve into topics like data privacy, surveillance, biotechnological advancements, and more.
Life-medical ethics
This concentration emphasizes the ethical challenges in biomedicine and healthcare. Topics explored may include genetic engineering, patient rights, medical experiments, and end-of-life decisions.
Artificial intelligence and big data ethics
This concentration responds to the national strategies for AI development and big data. Students in this track will gain proficiency in understanding the ethical frameworks related to AI and big data. They will also familiarize themselves with domestic and international policies, regulations, and standards regarding the ethical governance of AI and big data. Specialized courses for this concentration include "Ethics, Governance, and Compliance of Artificial Intelligence," "Data Ethics, Law, and Public Policy," and "Algorithm and Ethics Specialized Research."
Corporate governance ethics
This track focuses on the development and innovation of business in the age of globalization. Graduates will be trained to combine product and service innovations with corporate social responsibility. Courses in this concentration include "Introduction to Business Ethics," "Organizational Ethics in the 21st Century: ESG Special Topic," and "Business Ethical Decision-making."
Admissions
Each concentration has specific targeted audiences. For instance, the AI and Big Data Ethics track targets professionals involved in AI product development, design, and management, while the Business Ethics concentration aims at professionals in management, education, and research.
References
Higher education in China
Applied Ethics
Applied ethics | Master of Applied Ethics | [
"Biology"
] | 477 | [
"Behavior",
"Human behavior",
"Applied ethics"
] |
74,892,878 | https://en.wikipedia.org/wiki/Cosmetics%20policy | A cosmetics policy is a policy concerning the wearing of cosmetics, which may be required or forbidden in different places and circumstances. A cosmetics policy that applies to only one sex, such as a policy requiring women to wear lipstick or a policy forbidding men to wear nail polish, is considered a form of sex discrimination by some critics. Sex-specific cosmetics policies may place burdens on women workers and may also present difficulties for transgender and non-binary people. Sex-specific cosmetics policies are legal in many jurisdictions.
About
While many companies have mandatory cosmetics policies for women workers, the expectation that women wear cosmetics at work is often "unspoken". A gendered "grooming gap" in the workplace may have negative consequences for women workers, who may have to spend more money and time on cosmetics than men. Women workers may be disciplined, fired, or paid less if they do not wear cosmetics in the workplace. Companies with formal policies requiring that women wear makeup or that men cannot wear makeup have historically been permitted to have these gendered policies by federal courts in the United States.
By jurisdiction
Japan
Mandatory cosmetics policies for women workers are commonplace in Japan. Women workers in the beauty industry have been prohibited from wearing eyeglasses by some companies because the eyeglasses may prevent customers from clearly seeing the makeup worn by a worker. Japanese women have protested eyeglass bans and requirements for makeup and high heels on social media, but the policies remain legal in Japan.
United Kingdom
In 2019, Virgin Atlantic airlines announced that they would no longer have a policy requiring women workers to wear makeup.
In 2022, British Airways changed their uniform policy to be gender neutral. Makeup is now optional for women workers and male workers are now allowed to wear makeup and nail polish.
United States
20th century
In 1941, and for the duration of World War II, the wearing of red lipstick became mandatory for women who joined the United States Army.
21st century
In 2005, a worker alleged that she was dismissed from Harrah's Entertainment after she objected to the company's policy that women workers wear makeup. Her case, Jespersen v. Harrah's Operating Co., was considered by the United States Court of Appeals for the Ninth Circuit. The court decided that she was "justly fired" for refusing to wear makeup.
In 2014, a transgender teenager was instructed to remove her makeup before she could have her photograph taken for her drivers' license. A lawsuit against the South Carolina Department of Motor Vehicles resulted in a settlement allowing her to wear makeup in her photograph.
In 2017, a lawsuit in New Jersey alleged that a Cooper University Hospital worker was fired for wearing makeup to work. The worker claimed that a supervisor told him that "men should not wear make-up" in the workplace. The worker, a gay man, alleged discrimination on the basis of sexual orientation and gender non-conformity.
In 2018, a male student at Shadow Creek High School in Pearland, Texas, was disciplined after wearing makeup to school. Following controversy, the school district reevaluated its dress code which stipulated that "Boys may not wear make-up".
The Soldier's Blue Book, issued by the United States Army Training and Doctrine Command, states that men in the army are prohibited from wearing cosmetics unless medically necessary, but that women are permitted to wear cosmetics with any uniform as long as the cosmetics are applied "modestly and conservatively". Women in the army who wear cosmetics must apply cosmetics that "complement both the Soldier’s complexion and the uniform" and leadership are expected to "exercise good judgement" in enforcing the cosmetics policy. Women may not wear lipstick that "distinctly" differs from the shade of their lips and any cosmetics styles that are "Eccentric, exaggerated, or faddish" in their appearance are prohibited. Permanent cosmetics, including eyeliner and eyebrow makeup, may be permitted as long as it otherwise complies with the cosmetics guidelines.
Criticism
Sheila Jeffreys, a political science professor at the University of Melbourne, has criticized policies mandating makeup, claiming that the wearing of makeup by women is often "not simply a matter of choice in the workplace, but the result of a system of power relations." She has compared compulsory makeup policies to compulsory burqa policies that exist in some Muslim-majority countries.
See also
Gender-based dress codes
High heel policy
Trousers as women's clothing
References
External links
Is having to wear makeup sexist?, NBC News
Should Makeup Be Required in the Workplace?, Allure
Opinion: Vague guidance won’t stop women being forced to wear heels and makeup, The Guardian
Sexism: Can my employer make me wear make-up and heels?, BBC
Cosmetics law
Discrimination against LGBTQ people
Dress codes (legal)
Labour law
Sexism
Transgender rights
Women's rights
Working conditions | Cosmetics policy | [
"Chemistry"
] | 970 | [
"Cosmetics law",
"Regulation of chemicals"
] |
74,894,061 | https://en.wikipedia.org/wiki/Hospital%20socks | Hospital socks, also known as psych ward socks or grippy socks, are socks given to patients at hospitals, psychiatric facilities, and nursing homes. The socks have non-skid features to prevent patients from slipping and falling.
Patients can sometimes arrive at hospital by ambulance without footwear, and are typically provided with socks having a rubberised tread pattern to improve their grip strength. These non-slip socks are intended as alternative footwear to help prevent falls, but there is limited evidence for their usefulness.
Social media
Young people on social media commonly refer to hospital socks as "grippy socks". Slang terms for in-patient psychiatric hospitalization may include "grippy sock vacation", "grippy sock palace", "grippy sock jail", and "grippy sock hotel". Mental health professionals have expressed concern that such black humor may trivialize or romanticize the experience of psychiatric hospitalization. Some feel that tongue-in-cheek terms like "grippy sock vacation" can help destigmatize mental illness. Tags for "grippy socks" are a popular mental health-related tag on TikTok, where the tags have several hundred million views.
See also
Black comedy
Psychiatric hospital
References
External links
‘Grippy Socks Vacation’ and Our Media Diet, TheUnfilteredMagazine.com
Psych Ward Socks, KnowYourMeme.com
Significance of Grippy Socks in Psych Wards
Black comedy
Mental health
Nursing homes
Psychiatric hospitals
Social media
Socks | Hospital socks | [
"Technology"
] | 302 | [
"Computing and society",
"Social media"
] |
74,894,745 | https://en.wikipedia.org/wiki/Death%20of%20MohBad | On 12th September 2023, Nigerian musician MohBad died in Lagos, at the age of 26. A nurse who was reported by the Nigeria Police Force to have administered a Tetanus vaccine on him was arrested and found to be an unlicensed nurse on 19 September 2023 by the Lagos State Police Command.
#Justice4MohBad became a social movement and protest following his death and subsequent allegations about the events that led to it.
Prior events
On 10 September 2023, MohBad was last seen at the D'General Bitters Ikorodu show, where he performed with Zlatan, Seun Kuti, Poco Lee, Nasboi, DJ 4kerty, and the event host Do2dtun, in the lineup for the event. Other persons in attendance at the show include the CEO of D'General Bitters, Soso Berekon, and Cubana Chief Priest.
Circumstances
On 25 September 2023, Perez Medcare Hospital released a statement confirming MohBad was pronounced dead on arrival at the hospital.
Investigation
MohBad's death is an ongoing investigation led by Lagos Police Command. On 19 September 2023, the state Governor Babajide Sanwo-Olu invited Department of State Services (DSS) to join the ongoing investigation. MohBad's body was exhumed by the Lagos State Police Command on 21 September 2023. The autopsy was carried out and completed in the same day. On 22 September 2023, the Lagos State Police Public Relations Officer, Benjamin Hundeyin, in an interview with Punch newspapers, confirmed Mohbad's body was in the mortuary. On 24 September 2023, PRO Benjamin Hundeyin, issued a stern warning which reads, “The investigation will not be turned into a media trial”.
On 28 September 2023, Lagos State Police Command confirmed that Sam Larry was in custody and assisting with the ongoing investigation.
Allegations involving the Marlian Music
Assault and contract termination
On 5 October 2022, MohBad told the public, "I’m dying inside, and being physically assaulted under Naira Marley’s label". Shortly after MohBad made the claim, Naira Marley dismissed, MohBad's claim, 'adding that he was "high" when making the assault allegation'. On 6 October 2022, Mohbad gave details to his claim, saying "Naira Marley asked his boys to beat me for demanding a new manager". On 25 October 2022, MohBad terminated his contract with Marlian Music signed by his lawyer O.M. Falade, who issued the document to Marlian Music. In the document issued to Marlian Music, Mohbad claims he was physically attacked violently and has received life threats from Naira Marley. The document also stated that Marlian Music has not fulfilled the terms of the contract signed in 2019, and they had also failed to pay all royalties due to MohBad.
Unpaid royalties
Following his death, MohBad's management publicly requested the release of MohBad's royalties with Naira Marley's Marlian Music. On 22 September 2023, Nigerian journalist, Kemi Omololu-Olunloyo claimed that "Mohbad wrote 97% percent of all Marlian Music, and I discovered that as of today MohBad is worth ₦700M roughly around $690,000. Naira Marley's Marlian Music owes him ₦300M in song royalties".
Airplay ban
On 18 September 2023, Marlian Music catalogues which include Naira Marley and Zinoleesky were placed on ban from airplay by several radio and television stations in Nigeria, including Splash FM in Ibadan, who also ordered the ban to take effect across other radio stations in Oyo state. On 20 September 2023, Fresh 106.9 FM Ado Ekiti reportedly banned the airplay of all songs released under the Marlian Music and urged other radio stations to also ban their records. Ebonyi Broadcasting Television banned Naira Marley Marlian's recordings and evacuation of Marlian's studio albums from their studio. Invicta 98.9 FM also directed its employees to stop airplay of all the songs produced by the label effectively. Other radio stations that have also placed a ban on his songs include Island FM, Okin FM, Divine FM, and Agidigbo. On 21 September 2023, Okin 105.7FM Offa placed bans on Naira's songs On the same day, Kaduna reportedly banned all songs from Marlian Music from the radio. Cable TV like MTV Base and Soundcity also banned Malian Music.
Shows cancellation
On 18 September 2023, Fathia Entertainment announced the cancellation of Zinoleesky's US tour, which was to be held in 10 cities including Washington DC, New York, Atlanta, Dallas, Houston, Chicago, Cleveland, Los Angeles, Boston, and Indianapolis, beginning on 30 September 2023. A day after, Nigerian record producer Samklef set out to see all of Marlian's international shows get canceled following the death of MohBad.
Family and close friends of Mohbad
Family reaction
His dad said, "Don’t blame Naira Marley for my son’s death, as I tried my best to reach Naira Marley, but everything was in vain. When this issue happened, I wanted to treck to his house, but I was scared because I didn't know what I would meet there".
His mom believed her son was murdered, and not killed by any ear infection. According to Instablog, she believed his exit from Naira Marley's label Marlian Music led to his many troubles and death.
Friends' reactions
Bella Shmurda, who was MohBad's best friend, vows to see justice for his death legally or illegally. In a series of tweets, Bella has called for the arrest of Naira Marley and his associate, Sam Larry, over the death of MohBad. In January 2023, Bella revealed on a podcast titled #WithChude about a suicide attempted by MohBad, telling Chude Jideonwo, "Mohbad attempted to jump out of the window of his house before he was spotted by his girlfriend whose timely intervention prevented the suicide attempt".
Public reaction
Media and Internet coverage
On 12 September 2023, a Nigerian entertainment blog widely known as GistLover first broke the news of the death of MohBad. On 13 September 2023, according to GistLover, the person who called them said "MohBad was last seen at a show in Ikorodu, where he was hit with Juju (aka. supernatural power)". On 17 September 2023, a Nigerian music blog NaijaLoaded reportedly published a Fidelity Bank transaction receipt from the CEO of D'General Bitters, Soso Berekon supporting MohBad’s Son with ₦2 Million Naira.
On 19 September 2023, an auxiliary nurse who administered an anti-Tetanus vaccine on MohBad was disclosed to have been arrested by the Nigerian Police. The Nigerian actress Iyabo Ojo disclosed the information on her Instagram Live after her visit to the Lagos State Police Commissioner CP Abiodun Alabi. On 23 September 2023, the National Association of Nigeria Nurses and Midwives announced in a statement released stating that nurse who administered the injection is not a licensed nurse.
On 24 September 2023, Nigerian Tribune journalist Segun Adebayo published an article about Naira Marley under pressure to return to Nigeria, and the article was shortly deleted. The journalist wrote, "Marley who many people accused of being responsible for Mohbad’s death is said to have grown tired of being fingered in his former protégé’s death and may jet back into the country this weekend".
Record streams
MohBad's record streams increased 702% between September 12 – 14 2023, according to TurnTable during the last tracking week of music recorded by TurnTable charts in Nigeria which ends on Thursday and begins on Friday. TurnTable reportedly stated, "The Singer's catalog of songs collected 8.02 million on-demand streams – up from 999,000 on-demand streams the previous week (September 1 – 7)." On 15 September 2023, MohBad's single "Peace", released under Marlian Music, reached number 1 on Apple Music in Nigeria and was accompanied by his single "Ask About Me", released under his label Imolenization at number 2, "Beast & Peace" the opening track on Blessed extended play at number four and his "Feel Good" single at the fifth position. On the week of 23 September 2023, "Peace" debuted on Billboard Hot Trending Songs Powered by X at number 2.
On 18 September 2023, MohBad's extended play Blessed reached a new peak at number 4 and his first extended play Light made its first chart entry at number 20 in Nigeria Official Top 50 Albums. On 21 September 2023, according to Plus TV Africa MohBad's extended play Blessed gained over 530% on Streaming platforms. On 23 September 2023, he became the 46th best-selling digital artist in the world, surpassing international artists such as Nicki Minaj, Eminem, 21 Savage, Lady Gaga, and Chris Brown.
In 2023, MohBad set a new Spotify record with "Peace" after the demise. On 26 September 2023, "Peace" peaked at number 23 on Billboard U.S. Afrobeats Songs.
Aftermath
On 14 September 2023, a man who identified as a member of a cultist group in Ikorodu threatened to kill Naira Marley in a viral video if ever seen in Ikorodu.
Tributes
On 14 September 2023, Davido paid tribute to Mohbad at his Manchester show 'Timeless'. On 18 September 2023, Femi Adebayo, and Toyin Abraham paid tribute to Mohbad. On 19 September 2023, Khaid paid tribute to him and promised his son ₦2 Million Naira, then went on to release "Forever", which he dedicated to him. He also revealed that Mohbad's immediate family will receive 100% royalties from it. On 21 September 2023, Meek Mill, Lil Durk, and Kodak Black paid tribute. On 22 September 2023, MohBad was displayed on Times Square's billboard in New York. On 23 September 2023, Don Jazzy, Oxlade, and Rema got smoked over late tribute to MohBad.
#Justice4MohBad
The campaigners moved from social media using the #Justice4MohBad hashtag to an organized candlelight procession in Lagos held on 21 September 2023 commencing from Lekki Phase 1 Gate at 5 pm and terminating at Muri Okunola Park, Victoria Island, Lagos at 8 pm, where a musical concert was held, with Zlatan, Falz, Davido, and Shallipopi among others in attendance. On 22 September 2023, Abuja youths held a tribute concert at Unity Fountain. On 24 September 2023, Awka residents set to hold candlelight procession by 5 pm today at Ekwueme Square, and another candlelight procession was held on the same day, organized by his best friend Bella Shmurda in Canada. During the candlelight procession, Bella said, “My mum had to call me not to come back to Nigeria yet. I understand what she’s saying”.
Protest
On 19 September 2023, Lagos State joined the Justice for MohBad protest. On 20 September 2023, Ogun State, Oyo State, Kwara State, and Ondo State joined the protest demanding justice for Mohbad, followed by Bayelsa State and Ekiti State on 21 September 2023. On 22 September 2023, Delta State protesters demanded a DNA test on MohBad's son. In Nairobi, London, and New York, there was a peaceful protest through the cities in demand for justice.
Burial
On 13 September 2023, MohBad was buried in his hometown in Ikorodu, less than 24 hours after his death. According to Joseph Aloba, MohBad's dad; "In Yoruba land, his corpse is not the kind to be kept when both of his parents are still alive. That land where Mohbad was buried is his", he narrates during an interview with Temilola Sobola.
References
September 2023 events in Nigeria
2023 in Nigerian music
Deaths from medical malpractice
2023 deaths
Deaths by person in Nigeria
2023 in Lagos
2023 controversies
Vaccine controversies
Controversies in Nigeria
2023 protests
Protests in Nigeria | Death of MohBad | [
"Chemistry",
"Biology"
] | 2,609 | [
"Vaccination",
"Drug safety",
"Vaccine controversies"
] |
62,488,279 | https://en.wikipedia.org/wiki/Theorem%20of%20transition | In algebra, the theorem of transition is said to hold between commutative rings if
dominates ; i.e., for each proper ideal I of A, is proper and for each maximal ideal of B, is maximal
for each maximal ideal and -primary ideal of , is finite and moreover
Given commutative rings such that dominates and for each maximal ideal of such that is finite, the natural inclusion is a faithfully flat ring homomorphism if and only if the theorem of transition holds between .
Notes
References
Theorems in ring theory | Theorem of transition | [
"Mathematics"
] | 108 | [
"Algebra stubs",
"Algebra"
] |
62,490,588 | https://en.wikipedia.org/wiki/William%20Hamilton%20Shortt | William Hamilton Shortt (1881–1971) was a railway engineer and noted horologist, responsible for the design of the Shortt-Synchronome free pendulum clock, a widely used time standard, employed internationally in observatories in the period between the two World Wars. His deep involvement in precision timekeeping, as a colleague of Frank Hope-Jones and director of the Synchronome Company, derived from work on the safety of train travel and the accurate measurement of train speeds, following investigations into a serious train derailment of a LSWR train at Salisbury Station in 1906, when twenty-eight people died.
Shortt was born in September 1881 in Wimbledon, Surrey, only son to Charles Henry Shortt, a civil engineer, and Fanny (née Dobson) who was sister to the poet Henry Austin Dobson. He worked at the LSWR from 1902, starting as an articled pupil. He became an associate of the Institution of Civil Engineers in 1907. Shortt met Hope-Jones in 1910, and began collaborating in the design of master clocks from 1912, joining the Synchronome Company as a shareholder and director. He produced a series of designs involving new forms of escapement, attempting to optimise the delivery of energy to the pendulum, while taking account of variations in external factors such as temperature and atmospheric pressure. Shortt's experiments continued until 1916, when he was released from duties with the LSWR to serve as a captain in the Royal Engineers in France.
In 1919, having been demobilised from the army, he returned to his experimental work, producing a series of clocks in which he continued to try new ways of delivering an impulse to the pendulum, while attempting to make the pendulum do as little work as possible. The theoretical ideal was a pendulum operating freely in a vacuum and doing no work. Some of the best performances to date had been achieved by clocks housed in vacuum tanks, using a Riefler escapement.
Shortt's breakthrough in 1920 came with the development of a clock system, inspired by the work of R.J. Rudd of Croydon, championed by Hope-Jones, in which the task (each thirty seconds) of unlocking the impulse to an otherwise free pendulum was taken on by a separate slave clock, which in turn was corrected (as part of the same operating cycle) by a synchronising pulse derived from the master clock, containing the free pendulum. This system therefore utilised a mechanical phase-locked loop. Championed by the Astronomer Royal of Scotland, Ralph Allan Sampson, Shortt's free pendulum clock was rapidly adopted worldwide by many observatories as a time standard, and remained as such until the widespread adoption of quartz clocks from the Second World War onwards.
Shortt was honoured for his work in horology and precision timekeeping with the Gold Medal from the British Horological Institute in 1931 and its Fellowship in 1932, the John Price Wetherill Medal from the Franklin Institute in 1935, and the Tompion Medal of the Worshipful Company of Clockmakers in 1954. He was made a liveryman of the Company in 1931 and served as Master in 1950.
References
Extra reading
Frank Hope-Jones, Electrical Timekeeping (NAG: London, 1940)
R.H. Miles, Synchronome – Masters of Electrical Timekeeping (AHS: London, 2019), pp. 27–30, chapters 8 and 9.
1881 births
1971 deaths
Horology
Masters of the Worshipful Company of Clockmakers | William Hamilton Shortt | [
"Physics"
] | 715 | [
"Spacetime",
"Horology",
"Physical quantities",
"Time"
] |
62,494,102 | https://en.wikipedia.org/wiki/Julia%20Chan%20%28chemist%29 | Julia Y. Chan is a professor of chemistry and biochemistry at Baylor University. Chan is an expert in the area of intermetallic crystal growth with a focus on new quantum materials. She is a fellow of both the American Chemical Society and the American Association for the Advancement of Science.
Early life and education
Chan moved to New York City at the age of eight and spent her childhood in North America. Chan studied at Baylor University and graduated in 1993. Initially a music majorspecialising in the violinshe soon became interested in chemistry. At Baylor, Chan worked under the supervision of Carlos Manzanares and Marianna Busch. She earned her doctoral degree under the supervision of Susan M. Kauzlarich at the University of California, Davis in 1998. Chan completed postdoctoral research in the ceramics division at the National Institute of Standards and Technology. She has continued to play violin in her church orchestra.
Research and career
Chan began her career as an assistant professor of chemistry at Louisiana State University in 2000. In 2002 she was awarded an National Science Foundation CAREER Award and selected as one of the American Chemical Society women making an impact in chemistry. In 2004 Chan was awarded an ExxonMobil Faculty Fellowship Award. She was part of the 2010 American Chemical Society Women Chemists of Colour Summit. She joined the chemistry department at University of Texas at Dallas as a full professor in 2013. In 2022 Chan moved to Baylor University.
At the Baylor University, Chan investigates the physical properties of magnetic materials synthesized in her laboratory, with a focus on quantum materials that contain lanthanide cations. She has developed new techniques to grow single crystals of intermetallic phases. She was the Guest Editor of the American Chemical Society Inorganic Chemistry theme issue on Solid-State Inorganic Chemistry. In 2019 Chan was inducted into the American Association for the Advancement of Science.
Awards and honors
Her awards and honors include:
2003 American Crystallographic Association Margaret C. Etter Early Career Award
2004 Alfred P. Sloan Research Fellowship
2006 Baylor Alumni Association Outstanding Young Alum
2008 Iota Sigma Pi Agnes Fay Morgan Research Award
2016 University of Texas at Dallas Women Leading in Diversity Honouree
2019 American Chemical Society Wilfred T. Doherty Award for Excellence in Chemistry
2019 Elected Fellow of the American Association for the Advancement of Science
2024 Named Fellow of the American Chemical Society
Selected publications
Her publications include:
Chan is a Deputy Editor of Science Advances.
References
Living people
Baylor University alumni
University of California, Davis alumni
Louisiana State University faculty
University of Texas at Dallas faculty
American women chemists
Fellows of the American Association for the Advancement of Science
Fellows of the American Chemical Society
Year of birth missing (living people)
Solid state chemists
American women academics
21st-century American women scientists | Julia Chan (chemist) | [
"Chemistry"
] | 541 | [
"Solid state chemists"
] |
62,495,437 | https://en.wikipedia.org/wiki/Behavioral%20sleep%20medicine | Behavioral sleep medicine (BSM) is a field within sleep medicine that encompasses scientific inquiry and clinical treatment of sleep-related disorders, with a focus on the psychological, physiological, behavioral, cognitive, social, and cultural factors that affect sleep, as well as the impact of sleep on those factors. The clinical practice of BSM is an evidence-based behavioral health discipline that uses primarily non-pharmacological treatments (that is, treatments that do not involve medications). BSM interventions are typically problem-focused and oriented towards specific sleep complaints, but can be integrated with other medical or mental health treatments (such as medical treatment of sleep apnea, psychotherapy for mood disorders). The primary techniques used in BSM interventions involve education and systematic changes to the behaviors, thoughts, and environmental factors that initiate and maintain sleep-related difficulties.
The most common sleep disorders that can benefit from BSM include insomnia, circadian rhythm sleep-wake disorders, nightmare disorder, childhood sleep disorders (for example bedwetting, bedtime difficulties), parasomnias (such as sleepwalking, sleep eating), sleep apnea-associated difficulties (such as difficulty using continuous positive airway pressure), and hypersomnia-associated difficulties (for example daytime fatigue and sleepiness, psychosocial functioning).
Scope
The clinical practice of behavioral sleep medicine applies behavioral and psychological treatment strategies to sleep disorders. BSM specialists provide clinical services including assessment and treatment of sleep disorders and co-occurring psychological symptoms and disorders, often in conjunction with pharmacotherapy and medical devices that may be prescribed by medical professionals.
Most BSM treatments are based on behavioral therapy or cognitive behavioral therapy. Goals of BSM treatment include directly treating the sleep disorder (for example with cognitive behavioral therapy for insomnia), improving adherence to non-behavioral treatments (such as motivational enhancement for CPAP), and improving quality of life for people with chronic sleep disorders (for example, by using cognitive behavioral therapy for hypersomnia).
Training and certification
Behavioral sleep medicine is a clinical specialty practiced by individuals who are licensed health professionals, including psychologists, counselors, social workers, physicians, nurses, physical therapists, and other healthcare professionals. Licensed BSM practitioners work in a variety of settings, including sleep clinics, hospitals, universities, outpatient mental health clinics, primary care, and private practice. Some scientists conduct behavioral sleep medicine research but are not licensed health providers and do not directly provide clinical treatment.
Training in behavioral sleep medicine varies. Training may be obtained during graduate clinical training, internship/residency, fellowship/postdoctoral training, or through continuing education courses.
The Society of Behavioral Sleep Medicine has established a certification process whereby licensed health professionals who have met certain training requirements can earn the title of Diplomate in Behavioral Sleep Medicine (DBSM). Requirements include graduate course work, specialized clinical training, and passing a written exam. This certification was previously known as Certification in Behavioral Sleep Medicine (CBSM).
Diagnosis
Assessment methods used in behavioral sleep medicine are similar to those used in sleep medicine as a whole. Methods include clinical interview, sleep diaries, standardized questionnaires, polysomnography, actigraphy, and multiple sleep latency test (MSLT).
The third edition of the International Classification of Sleep Disorders (ICSD-3) contains the diagnostic criteria for sleep disorders. Many of these disorders are also described in the diagnostic manual of the American Psychiatric Association, the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5).
Insomnia
Insomnia, which is the most common sleep disorder in the population as well as the most common disorder treated by BSM practitioners, is typically evaluated with a clinical interview and two weeks of sleep diaries. The clinical interview examines topics such as sleep patterns, sleep history, psychiatric history, medications, substance use, and relevant medical, developmental, social, occupational, cultural, and environmental factors. For young children, the clinical interview and sleep diaries would be completed primarily by a parent.
Standardized questionnaires may be used to evaluate the severity of the sleep problem or assess for other possible sleep problems. Example questionnaires commonly used with adults include: Insomnia Severity Index, Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, and STOP-Bang. The Brief Infant Sleep Questionnaire is commonly used to assess sleep/wake patterns in infants and small children. Questionnaires commonly used with children and their parents include: Children's Sleep Habits Questionnaire, the Pediatric Sleep Questionnaire, and the Children's Report of Sleep Patterns. Questionnaires commonly used with adolescents include: The Adolescent Sleep Wake Scale and the Adolescent Sleep Hygiene Scale.
Overnight sleep studies (polysomnography) are not necessary or recommended to diagnose insomnia. Polysomnography is used to rule out the presence of other disorders which may require medical treatment, such as sleep apnea, periodic limb movement disorder, and rapid eye movement sleep behavior disorder. An MSLT is used to rule out disorders of hypersomnolence such as narcolepsy.
Actigraphy is sometimes used to gain information about sleep timing and assess for possible circadian rhythm disorders.
Other sleep concerns
Assessment of other sleep concerns follow similar procedures to those for assessing insomnia. By the time individuals are referred to a BSM specialist, they have often already seen a sleep medicine provider and completed any necessary testing such as polysomnography, MSLT, or actigraphy. In that case, the BSM provider conducts a clinical interview and administers questionnaires if needed. Individuals are often asked to track their sleep or sleep-related symptoms such as nightmares or sleepwalking episodes that are the focus of treatment.
Management
BSM practitioners provide evidence-based treatments developed for specific sleep disorders, including some that are published in clinical guidelines of organizations such as the American Academy of Sleep Medicine. BSM interventions are typically brief (between one and eight sessions), structured, and cognitive-behavioral in nature, aiming to provide the education and skills for individuals to become more independent in managing their sleep disorder.
Infants, children, and adolescents
The most common sleep complaints of parents of infants include requiring a parent or specific condition, like rocking, or bouncing, to fall asleep, and struggling to return to sleep during nighttime awakenings. Among toddlers and preschoolers, nighttime fears or resisting/stalling at bedtime (and therefore delaying sleep onset) are common, as well as bedtime co-sleeping with parents or siblings. In school-aged youth, problems with falling or staying asleep due to poor sleep hygiene are common.
Insufficient sleep (sleeping under the recommended 8–10 hours) is common in adolescence. The other most common sleep disorders of adolescence include insomnia and delayed sleep-wake phase disorder. High rates of insufficient sleep in adolescence are partially attributed to a mismatch between adolescent biology and school start times. Because adolescents experience a natural shift in their circadian rhythm around puberty (with a preference for later bedtimes and wake times), the American Academy of Pediatrics recommends that high schools start no earlier than 8:30am.
Evidence-based treatments for childhood behavioral sleep disorders vary by developmental level, but typically include heavy parental involvement. Interventions generally focus on:
Stabilizing the timing of the sleep/wake schedule to be consistent on school nights and weekends
Scheduling enough time in bed to meet clinical guidelines for developmentally appropriate sleep duration
Promoting healthy bedtime routines that help prepare the body for sleep
Empowering parents to set limits and rules around expected bedtime behavior
Promoting independent sleep
Promoting consistent sleep locations
Addressing any other barriers to sleep onset (such as nightmares, bedtime fears, fear of the dark, anxiety, depression, pain or discomfort, etc.)
Addressing family-level barriers to consistently wearing CPAP to treat obstructive sleep apnea and hypoventilation
Treatment with parents of infants emphasizes the implementation of safe sleeping practices in order to reduce the risk of sudden infant death syndrome. The recommends that infants 0–12 months of age sleep:
On their back
On their own protected sleep surface, such as a crib or other firm sleep surface, and not in the parent's bed, chair, or sofa
With no heavy blankets, pillows, bumper pads or positioning devices near to them
Adults
Evidence-based treatments used to treat adult sleep-related disorders include:
Cognitive behavioral therapy for insomnia (CBT-I). This is an evidence-based, non-pharmacological treatment for insomnia disorder that uses education and systematic changes to insomnia-related behaviors, thoughts, and environment to change the factors that maintain chronic difficulties with falling asleep, staying asleep, and getting restorative sleep. CBT-I is the first-line treatment for insomnia disorder as recommended by the American College of Physicians and American Academy of Sleep Medicine. It is effective for insomnia disorder that occurs alone or along with other medical or psychiatric symptoms.
Intensive sleep retraining
Mindfulness-based therapy for insomnia (MBTI)
Imagery rehearsal therapy (IRT) for nightmare disorder
Exposure, relaxation, and rescripting therapy (ERRT) for nightmare disorder
Motivational enhancement therapy for improving adherence to CPAP treatment
Exposure therapy for CPAP claustrophobia
Behavioral therapy for circadian rhythm sleep-wake disorders
Clinical hypnosis for NREM parasomnias
Cognitive behavioral therapy for hypersomnia
Sleep extension
See also
Behavioral medicine
References
Sleep disorders
Sleep medicine | Behavioral sleep medicine | [
"Biology"
] | 1,918 | [
"Behavior",
"Sleep",
"Sleep disorders",
"Sleep medicine"
] |
62,496,682 | https://en.wikipedia.org/wiki/Curly%20pine | Curly pine is pine wood with a wavy pattern similar to that of curly maple.
On their website, the wood supplier Blackwood Timber Company says, "Curly pine is the coolest grain pattern that you can possibly expect out of an ancient long leaf pine."
References
Pinaceae
Wood | Curly pine | [
"Physics"
] | 58 | [
"Materials stubs",
"Materials",
"Matter"
] |
62,496,770 | https://en.wikipedia.org/wiki/Multifactorial%20disease | Multifactorial diseases are not confined to any specific pattern of single gene inheritance and are likely to be caused when multiple genes come together along with the effects of environmental factors.
In fact, the terms 'multifactorial' and 'polygenic' are used as synonyms and these terms are commonly used to describe the architecture of disease causing genetic component. Multifactorial diseases are often found gathered in families yet, they do not show any distinct pattern of inheritance. It is difficult to study and treat multifactorial diseases because specific factors associated with these diseases have not yet been identified. Some common multifactorial disorders include schizophrenia, diabetes, asthma, depression, high blood pressure, Alzheimer's, obesity, epilepsy, heart diseases, Hypothyroidism, club foot, cancer, birth defects and even dandruff.
The multifactorial threshold model assumes that gene defects for multifactorial traits are usually distributed within populations. Firstly, different populations might have different thresholds. This is the case in which occurrences of a particular disease is different in males and females (e.g. Pyloric stenosis). The distribution of susceptibility is the same but threshold is different. Secondly, threshold may be same but the distributions of susceptibility may be different. It explains the underlying risks present in first degree relatives of affected individuals.
Characteristics
Multifactorial disorders exhibit a combination of distinct characteristics which are clearly differentiated from Mendelian inheritance.
The risk of multifactorial diseases may get increased due to environmental influences.
The disease is not sex-limited but it occurs more frequently in one gender than the other; females are more likely to have neural tube defects compared to males.
The disease occurs more commonly in a distinct ethnic group (i.e., Africans, Asians, Caucasians etc.)
The diseases may have more in common than generally recognized since similar risk factors are associated with multiple diseases.
Families with close relatives are more likely to develop one of the disease than the common population. The risk may heighten anywhere between 12 and 50 percent depending on the relation of the family member.
Multifactorial disorders also reveal increased concordance for disease in monozygotic twins as compared to dizygotic twins or full siblings.
Risk Factors
The risk for multifactorial disorders is mainly determined by universal risk factors. Risk factors are divided into three categories; genetic, environmental and complex factors (for example overweight).
Genetic risk factors are associated with the permanent changes in the base pair sequence of human genome. In the last decade, many studies have been generated data regarding genetic basis of multifactorial diseases. Various polymorphism have been shown to be associated with more than one disease, examples include polymorphisms in TNF-a, TGF-b and ACE genes, as well as mutations in BRCA1. BRCA2, BARD1, and BRIP1.
Environmental risk factors vary from events of life to medical interventions. The quick change in the patterns of morbidity, within one or two generations, clearly demonstrates the significance of environmental factors in the development and reduction of multifactorial disorders. Environmental risk factors include change in life style (diet, physical activity, stress management) and medical interventions (surgery, drugs).
Many risk factors originate from the interactions between genetic and environmental factors and referred as complex risk factors. Examples include epigenetic changes, body weight, pollution, and plasma cortisol level.
Multifactorial Disorders; Continuous or Discontinuous
Autosomal or sex-linked single gene conditions generally produce distinct phenotypes, said to be discontinuous: the individual either has the trait or does not. However, multifactorial traits may be discontinuous or continuous.
Continuous traits exhibit normal distribution in population and display a gradient of phenotypes while discontinuous traits fall into discrete categories and are either present or absent in individuals. It is interesting to know that many disorders arising from discontinuous variation show complex phenotypes also resembling continuous variation This occurs due to the basis of continuous variation responsible for the increased susceptibility to a disease. According to this theory, a disease develops after a distinct liability threshold is reached and severity in the disease phenotype increases with the increased liability threshold. On the contrary, disease will not develop in the individual who does not reach the liability threshold. Therefore, an individual either having disease or not, the disease shows discontinuous variation.
An example of how the liability threshold works can be seen in individuals with cleft lip and palate. Cleft lip and palate is a birth defect in which an infant is born with unfused lip and palate tissues. An individual with cleft lip and palate can have unaffected parents who do not seem to have a family history of the disorder.
History
Francis Galton was the first scientist who studied multifactorial diseases and was the cousin of Charles Darwin. Major focus of Galton was on 'inheritance of traits' and he observed "blending" characters. The average contribution of each several ancestor to the total heritage of the offspring and is now known as continuous variation. When a trait (human height) exhibiting continuous variation is plotted against a graph, the majority of population distribution is centered around the mean. Galton's work is contrary to work done by Gregor Mendel; as the latter studied "nonblending" traits and kept them in different categories. The traits exhibiting discontinuous variation, occur in two or more distinct forms in a population as Mendel found in color of petals.
See also
Genetic disorders
polygenes
Quantitative trait locus
References
Genetics
Diseases and disorders | Multifactorial disease | [
"Biology"
] | 1,167 | [
"Genetics"
] |
62,498,333 | https://en.wikipedia.org/wiki/Personal%20Data%20Protection%20Bill%2C%202019 | The Personal Data Protection Bill, 2019 (PDP Bill 2019) was a proposed legislation by the Parliament of India which was withdrawn. The bill covers mechanisms for protection of personal data and proposes the setting up of a Data Protection Authority of India for the same. Some key provisions the 2019 Bill provides for which the 2018 draft Bill did not, such as that the central government can exempt any government agency from the Bill and the Right to Be Forgotten, have been included.
Background and timeline
In July 2017, the Ministry of Electronics and Information Technology set up a committee to study issues related to data protection. The committee was chaired by retired Supreme Court judge Justice B. N. Srikrishna.
The committee submitted the draft Personal Data Protection Bill, 2018 in July 2018.
After further deliberations the Bill was approved by the cabinet ministry of India on 4 December 2019 as the Personal Data Protection Bill 2019 and tabled in the Lok Sabha on 11 December 2019.
As of March 2020 the Bill was being analyzed by a Joint Parliamentary Committee (JPC) in consultation with experts and stakeholders. The JPC, which was set up in December 2019, was headed by Meenakshi Lekhi, Member of Parliament. While the JPC was tasked with a short deadline to finalize the draft law before the Budget Session of 2020, it has sought more time to study the Bill and consult stakeholders.
The bill was withdrawn in August 2022.
Provisions
The Bill aims to:
It provided for extensive provisions around collection of consent, assessment of datasets, data flows and transfers of personal data, including to third countries and other aspects around anonymized and non-personal data.
Criticism
The revised 2019 Bill was criticized by Justice B. N. Srikrishna, the drafter of the original Bill, as having the ability to turn India into an “Orwellian State". In an interview with Economic Times, Srikrishna said that, "The government can at any time access private data or government agency data on grounds of sovereignty or public order. This has dangerous implications.” This view is shared by a think tank in their comment number 3.
Fresh criticism on the international level comes from an advisor to a group proposing an alternative text. A moderately critical summary is available from an India scholar working with an American co-author.
The role of social media intermediaries is being regulated more tightly on several fronts. The Wikimedia Foundation is hoping that the PDP bill will prove the lesser evil compared with the Draft Information Technology [Intermediary Guidelines (Amendment) Rules] 2018.
Forbes India reports that "there are concerns that the Bill [...] gives the government blanket powers to access citizens' data."
Jaiveer Shergill, a prominent Supreme Court Lawyer has shared the pitfalls and gaps of the current version of the draft bill. There are serious loopholes of how the bill is unable to identify the scope of governmental bodies in distinguishing who has access to the personal data of the citizens and missing state bodies to monitor the personal data.
Withdrawal
The Data Protection Bill was withdrawn from the Lok Sabha and the Parliament as reported in the Bulletin - Part 1 No. 189 dated August 3, 2022. The withdrawal of the Data Protection Bill come with reports that a more comprehensive version of the Bill may be introduced.
The Digital Personal Data Protection Act, 2023 was passed by the Parliament of India and received the assent of the President of India making it the country's data protection legislation after the withdrawal of Personal Data Protection Bill, 2019.
See also
Information Technology (Intermediary Guidelines (Amendment) Rules) 2018
Digital Personal Data Protection Act, 2023
UK Data Protection Act 2018
EU General Data Protection Regulation
UK Data Protection Act 1998
Data security
Further reading
Privacy on the Line: What do Indians think about privacy and data protection
Data Protection Bill withdrawn: Roadblocks towards a comprehensive data protection framework
Notes
References
External links
The draft of the 2018 bill
Personal Data Protection Bill 2019
PDP Bill 2019: Impact on tech companies
Information privacy
Data laws of Asia
Data protection
2019 in Indian law
Computing legislation
Information technology in India
Censorship in India
Internet in India
2018 in Indian law
Medical privacy legislation
Modi administration
Computer security in India | Personal Data Protection Bill, 2019 | [
"Engineering"
] | 844 | [
"Cybersecurity engineering",
"Information privacy"
] |
62,500,340 | https://en.wikipedia.org/wiki/Banting%20Medal | The Banting Medal, officially the Banting Medal for Scientific Achievement, is an annual award conferred by the American Diabetes Association (ADA), which is the highest award of ADA. Inaugurated in 1941, the prize is given in memory of Sir Frederick Banting, a key discoverer of insulin and its therapeutic use.
Laureates
1941: Elliott P. Joslin
1942: William Muhlberg
1943: Fred W. Hipwell
1944: Leonard G. Rowntree
1946: Bernardo Alberto Houssay, Hans Christian Hagedorn, Robert Daniel Lawrence, Eugene Lindsay Opie, University of Toronto
1947: George Henry Alexander Clowes
1948: Rollin Turner Woodyatt
1949: Herbert M. Evans, Frederick Madison Allen
1950: Frank George Young
1951: Cyril Norman Hugh Long
1952: Robert Russell Bensley
1953: Shields Warren, Walter R. Campbell, Andrew Almon Fletcher
1954: Henry Hallett Dale
1955: Carl Ferdinand Cori, Eugene Floyd DuBois
1956: William C. Stadie, Louis Harry Newburgh
1957: DeWitt Stetten Jr., John Raymond Murlin
1958: Jerome W. Conn, William H. Olmsted
1959: George Widmer Thorn, Elexious Thompson Bell
1960: Priscilla White, James Collip
1961: Rachmiel Levine
1962: Albert Baird Hastings
1963: Bernardo Alberto Houssay, Garfield G. Duncan
1964: Francis Dring Wetherill Lukens, Moses Barron, Joseph Pierre Hoet, Leland S. McKittrick, Peter J. Moloney, David A. Scott, Haim Ernst Wertheimer
1965: Solomon Aaron Berson, I. Arthur Mirsky
1966: Robert Hardin Williams
1967: Alexander Marble
1968: Arthur R. Colwell
1969: Earl Wilbur Sutherland, Robert L. Jackson
1970: Paul Eston Lacy
1971: George F. Cahill Jr., William R. Kirtley
1972: Dorothy Crowfoot Hodgkin
1973: Arnold Lazarow
1974: Albert Renold
1975: Roger H. Unger
1976: Donald F. Steiner
1977: David M. Kipnis
1978: Stefan S. Fajans
1979: Charles Rawlinson Park
1980: Norbert Freinkel
1981: Lelio Orci
1982: Jesse Roth
1983: Arthur H. Rubenstein
1984: Daniel W. Foster
1985: Bjorn Nerup
1986: Albert I. Winegrad
1987: Joseph Larner
1988: Gerald Reaven
1989: Ora Rosen
1990: Daniel Porte Jr.
1991: Mladen Vranic
1992: Gian Franco Bottazzo
1993: C. Ronald Kahn
1994: Philip E. Cryer
1995: Franz M. Matschinsky
1996: Peter H. Bennett
1997: Alan D. Cherrington
1998: Jerrold M. Olefsky
1999: Anthony Cerami
2000: Michael P. Czech
2001: John Denis McGarry
2002: Samuel W. Cushman
2003: Aldo A. Rossini
2004: Michael A. Brownlee
2005: Jeffrey Scott Flier
2006: Richard N. Bergman
2007: Robert Stanley Sherwin
2008: Ralph A. DeFronzo
2009: George Eisenbarth
2010: Robert A. Rizza
2011: Barbara E. Corkey
2012: Bruce M. Spiegelman
2013: Graeme I. Bell
2014: Daniel J. Drucker
2015: Philipp E. Scherer
2016: Barbara Kahn
2017: Domenico Accili
2018: Gerald I. Shulman
2019: Stephen P. O'Rahilly
2020: Ele Ferrannini
2021: Jens Juul Holst
2022: Frances Ashcroft
2023: Matthias Tschöp
See also
Banting Lectures
Kelly West Award
References
External links
Banting lectures
Awards established in 1941
Medicine awards
American Diabetes Association
1941 establishments in the United States | Banting Medal | [
"Technology"
] | 763 | [
"Science and technology awards",
"Medicine awards"
] |
62,500,877 | https://en.wikipedia.org/wiki/HD%20182681 | HD 182681 (186 G. Sagittarii) is a single, blue-hued star in the zodiac constellation of Sagittarius. It has an apparent visual magnitude of +5.64, which is bright enough to be visible to the naked eye in good conditions. Based upon an annual parallax shift of as seen from Earth, this star is located around 233 light years from the Sun. It is moving away from the Sun with a radial velocity of 1.40 km/s.
This is a B-type main sequence star with a stellar classification of B8.5V. The star is about 107 million years old and is spinning rapidly with a projected rotational velocity of 277 km/s. It has an infrared excess, which suggests a debris disk is orbiting the star at a radius of with a mean temperature of 90 K.
References
B-type main-sequence stars
Circumstellar disks
Sagittarius (constellation)
Durchmusterung objects
182681
95619
7380 | HD 182681 | [
"Astronomy"
] | 211 | [
"Sagittarius (constellation)",
"Constellations"
] |
62,501,305 | https://en.wikipedia.org/wiki/P%C3%B3sa%27s%20theorem | Pósa's theorem, in graph theory, is a sufficient condition for the existence of a Hamiltonian cycle based on the degrees of the vertices in an undirected graph. It implies two other degree-based sufficient conditions, Dirac's theorem on Hamiltonian cycles and Ore's theorem. Unlike those conditions, it can be applied to graphs with a small number of low-degree vertices. It is named after Lajos Pósa, a protégé of Paul Erdős born in 1947, who discovered this theorem in 1962.
The Pósa condition for a finite undirected graph having vertices requires that, if the degrees of the vertices in increasing order as
then for each index the inequality is satisfied.
Pósa's theorem states that if a finite undirected graph satisfies the Pósa condition, then that graph has a Hamiltonian cycle in it.
References
Katona–Recski–Szabó: A számítástudomány alapjai, Typotex, Budapest, 2003, (Hungarian undergraduate level course book).
External links
About the Pósa theorem
Graph theory
Mathematical theorems | Pósa's theorem | [
"Mathematics"
] | 228 | [
"Theorems in graph theory",
"Theorems in discrete mathematics"
] |
62,502,370 | https://en.wikipedia.org/wiki/Nontrigonal%20pnictogen%20compounds | Nontrigonal pnictogen compounds refer to tricoordinate trivalent pnictogen (phosphorus, arsenic, antimony and bismuth: P, As, Sb and Bi) compounds that are not of typical trigonal pyramidal molecular geometry. By virtue of their geometric constraint, these compounds exhibit distinct electronic structures and reactivities, which bestow on them potential to provide unique nonmetal platforms for bond cleavage reactions.
Synthesis
The first examples of nontrigonal pnictogen compound were synthesized by Arduengo and co-workers in 1984, through condensation of a diketoamine with a phosphorus trihalide in the presence of base. This group reported also on the first systematic investigations into its chemical behavior. Later, on similar routes, the corresponding and isostructural arsenic and antimony species were also synthesized. Other synthetic methods involve deprotonation of OH or NH groups in the presence of ECl3 (E=P, As, Sb and Bi), salt metathesis or reduction of pentavalent pnictogen compounds.
Structures and properties
The molecular structures of nontrigonal pnictogen compounds reveal the steric strain in these molecules, and significantly differing bond angles at the pnictogen atoms indicate a considerable distortion of the coordination spheres.
In particular, the geometry at the central part of these compounds deviate strongly from traditional pnictogen compounds, and indicate molecular strain with an approach to a T-type molecular configuration. With different ligand motifs, the bond angles at pnictogen atoms can vary from 100˚ to almost 180˚. The flattened geometry of these molecules influences the relatively low energetic barriers for inversion of the configuration via planar coordinated pnictogen atoms in the transition state. These low barriers are in accordance with the dynamic behavior and fast equilibration processes observed in ambient temperature NMR.
Results of quantum chemical calculations confirm that in these compounds, the lone pair of electrons at the pnictogen atoms is localized in orbitals with relatively high s-character. From these results, only weak nucleophilicity was derived in accordance with some experimental observations such as the inertness towards benzyl bromide. The LUMO is delocalized but has important contributions from pnictogen empty p orbitals, which should favor a nucleophilic attack of substrates at this position in accordance with experimental findings. The pnictogen atom forms a three-center-four-electron bond with the two flanking nitrogen atoms, which is manifested by the HOMO-2.
For nontrigonal bismuth compounds, a Bi(I) electronic structure could be shown to be most appropriate. Natural bond orbital (NBO) analysis reveals an s-type lone pair and a p-type lone pair at the metal, with the remaining two p orbitals being involved in one two-center-two-electron bond and one three-center-two-electron bond. The p-type lone pair NBO has less than 2 electron occupancy as it is delocalized over the ligand frame. Although considerable Bi(I) character is indicated for the Bi compound, it exhibits reactivity similar to Bi(III) electrophiles, and expresses either a vacant or a filled p orbital at Bi.
From these results, two types of resonance structures can be drawn, one with a filled s-orbital and a vacant p orbital at the pnictogen center, the other one with negative charge on pnictogen, arising from the redox-non-innocent nature of the ligand. This is evident by shorter C-N bond lengths in nontrigonal pnictogen compounds than C-N single bonds in the corresponding ligands. These structures may reflect the specific bonding situation in these strained molecular systems.
Reactivity
These easily available and sterically constrained compounds are potentially suitable for an application in a wide variety of secondary processes such as small molecule activation or the generation of new catalysts based on main-group and transition-metal elements.
Redox reactions
Since the LUMOs of nontrigonal pnictogen compounds consist mainly of the vacant p orbitals of the pnictogen nuclei, they could undergo one-electron reduction to afford radical anions if the energy levels of LUMOs are appropriate. For a less sterically hindered compound, the generated radical anion readily dimerizes to form a dianion with a P-P bond. When a sterically encumbered tris-amide ligand is used, stable radical anions bearing T-shaped pnictogen nuclei can be isolated and characterized.
The oxidation of nontrigonal phosphorus compounds and transfer of halogen molecules to the phosphorus atoms to generate phosphoranes with phosphorus atoms in an oxidation state of +5 was achieved by various synthetic procedures. These dihalides are promising starting materials and potentially applicable for the generation of numerous secondary products, but only few reactions have been reported so far in the literature. Nontrigonal phosphorus compounds can also be oxidized by organic azide to yield phosphazenes.
Oxidative addition
These sterically constrained phosphorus compounds show remarkable reactivity towards protic reagents such as primary amines and alcohols, which results in intermolecular oxidative addition of these O−H and N−H bonds. This reaction tolerates a variety of different substrates, including ammonia and water. Two mechanisms have been suggested for the understanding of the unusual insertion of phosphorus atoms into polar X−H bonds by oxidative addition.
Nontrigonal phosphorus compounds can also react with ammonia–borane to form a formal dihydrogen oxidative addition product. This compound proved to facilitate the catalytic reduction of azobenzene.
Coordination chemistry
The first transition metal complexes of nontrigonal pnictogen compounds have been reported in the 1980s and '90s. Up to now, several complexes have been successfully synthesized, but they have not yet been applied in secondary processes, such as catalytic cycles.
In 2018, the synthesis and reactivity of a chelating ligand containing a nontrigonal phosphorus center was reported. It is worth noting that, apart from direct metalation of this ligand with RuCl2(PPh3)3, metalation with a ruthenium hydride compound RuHCl(CO)(PPh3)3 yields a complex with net insertion into the Ru−H bond. These ligands, along with recent developments for higher valent states of Sb ligands, may possess rich potential in the field of catalysis and sensing.
See also
Phosphine
Organophosphorus compound
Organoarsenic chemistry
Organoantimony chemistry
Organobismuth chemistry
References
Pnictogens
Inorganic compounds | Nontrigonal pnictogen compounds | [
"Chemistry"
] | 1,380 | [
"Inorganic compounds"
] |
62,502,389 | https://en.wikipedia.org/wiki/Chemical%2C%20Paper%20and%20Ceramic%20Union | The Chemical, Paper and Ceramic Union () was a trade union representing chemical, oil refinery, paper, rubber, ceramics, glass and plastics workers in West Germany.
While the Factory Workers' Union of Germany, dissolved by the Nazis in 1933, was seen as the forerunner of the union, IG Chemie was established on 14 October 1948.
The third largest affiliate of the German Trade Union Confederation for much of its history, the union initially struggled with Allied attempts to limit the chemicals industry in West Germany. However, from 1958 it began seeing wage increases for its members above the rate of inflation, and also saw major successes in health and safety. During the 1960s, it was seen as a radical, left-wing union, but by the 1970s, it was associated with the right-wing of the union movement, and criticised for its top-down approach.
In 1991, the East German Industrial Union of Chemicals, Glass and Ceramics merged into the union. By 1996, it had 694,897 members. The following year, it merged with the Union of Mining and Energy and the Leather Union, to form IG Bergbau, Chemie, Energie.
Presidents
1946: Otto Adler
1949: Wilhelm Gefeller
1969: Karl Hauenschild
1982: Hermann Rappe
1995: Hubertus Schmoldt
References
Chemical industry trade unions
German Trade Union Confederation
Trade unions established in 1948
Trade unions disestablished in 1997 | Chemical, Paper and Ceramic Union | [
"Chemistry"
] | 290 | [
"Chemical industry trade unions"
] |
77,851,730 | https://en.wikipedia.org/wiki/Ophelia%20Tsui | Ophelia Kwan Chui Tsui (, born 1967) is a Chinese physicist who studies experimental polymer science, particularly focusing on the physical properties and glass transition behavior of thin films of polymers, and their study using atomic force microscopy and dielectric spectroscopy. She is a professor of physics at Hong Kong University of Science and Technology, where she directs the William Mong Institute of Nano Science and Technology.
Education and career
Tsui has a bachelor's degree from the University of Hong Kong and a Ph.D. from Princeton University, completed in 1996.
After postdoctoral research at the Massachusetts Institute of Technology and University of Massachusetts Amherst, she became an assistant professor of physics at Hong Kong University of Science and Technology (HKUST) in 1998. She moved to Boston University from 2007 until 2017, when she returned to HKUST.
Recognition
Tsui was elected as a Fellow of the American Physical Society (APS) in 2011, after a nomination from the APS Division of Polymer Physics, "for outstanding contributions on the dynamics of thin polymer films".
References
External links
Home page
1967 births
Living people
Chinese physicists
Chinese women physicists
Polymer scientists and engineers
Alumni of the University of Hong Kong
Princeton University alumni
Academic staff of the Hong Kong University of Science and Technology
Boston University faculty
Fellows of the American Physical Society | Ophelia Tsui | [
"Chemistry",
"Materials_science"
] | 263 | [
"Polymer scientists and engineers",
"Physical chemists",
"Polymer chemistry"
] |
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