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75,078,890 | https://en.wikipedia.org/wiki/Dithionitronium%20hexafluoroarsenate | Dithionitronium hexafloroarsenate is the inorganic compound with the formula . It is the hexafluoroarsenate () salt of S=N=S+. The cation is of interest as the sulfur analogue of nitronium (). Hexafloroarsenate is a weakly coordinating anion. According to X-ray crystallography, S=N=S+ is linear with S-N distances of 146 picometers.
Synthesis and reactions
Dithionitronium hexafluoroarsenate is prepared from thiazyl chloride using silver hexafluoroarsenate. The hexachloroantimonate salt can be prepared by treating thiazyl chloride with sulfur in the presence of antimony pentachloride according to this idealized equation:
The dithionitronium cation reacts with nitriles to give dithiadiazolium salts:
Addition to alkynes gives dithiazolium salts:
References
Sulfur–nitrogen compounds
Arsenic(V) compounds
Fluorometallates
Salts | Dithionitronium hexafluoroarsenate | [
"Chemistry"
] | 229 | [
"Salts"
] |
75,080,081 | https://en.wikipedia.org/wiki/Friendship%20recession | The friendship recession is a decline in the number of friends people have in Canada and the United States. The decline first began in the late 20th century. This phenomenon is theorized to have a wide range of impacts on mental and physical health.
Statistics
USA
Surveys show that the number of close friends people have on average has decreased. Those who state they have 10+ close friends, excluding family members, was 33% in 1990, but has now decreased to 13% in 2021. Men seem more affected. The number of American men without a close friend has jumped five times since 1995, from 3% to 15% between 1990 and 2021.
Canada
Canadian seniors can often feel more lonely than the general population. Ageism, the community environment and dementia can put them more at risk.
Impacts
Social isolation significantly increases a person's risk of premature death from all causes, a risk that may rival that of smoking, obesity, and physical inactivity. It also creates a higher likelihood of becoming depressed or anxious, or committing suicide. One study in Germany showed that having several friends is correlated with fewer worries about the economy and higher life satisfaction.
Those without friends are more likely to feel lonely. Chronic loneliness is linked to poorer sleep and increases the odds of cardiovascular disease as much as smoking 15 cigarettes per day would. This may be because people who are chronically lonely develop long-term "fight-or-flight" stress signaling, which negatively affects immune system functioning, leading to less immunity and more inflammation.
Finally, in a study evaluating 99 countries, it was found that those who prioritize friendships tend to be happier, especially if they are women, older people, less educated or people of an individualistic culture. Friendships becoming less prioritized in North America may mean that the friendship recession is causing a decrease in happiness for the average citizen.
Potential causes
Some cite bad urban planning practices as a cause of the friendship recession because it has led to the destruction of inexpensive third places to meet new people or to socialize with people one already knows. Poor city design has also led to the proliferation of car dependency, suburbia and urban sprawl, which make meeting with existing friends more time-consuming, expensive and difficult while also reducing the likelihood that one will talk to strangers.
Some cite economic factors. Because the value of wages have stagnated since the late 20th century, precarious work is on the rise and people receive fewer job benefits, people may often choose to focus on work or school more instead of investing time in friendships.
Culture may also play a role in creating destructive expectations, for example, the idea that friendships need to be forever, or that occasional conflicts are not ok, or that there is an ideal form of friendship, or that friends should simply know what their friend needs without being told are all false and can harm existing friendships.
Some believe the rise of workism, the belief that work is the most important aspect of life and the source of identity and meaning, is a factor. Workism, on top of creating of culture of competition, stress and burnout, can make people prioritize their careers over their personal relationships and hobbies.
Many believe increased technology and social media usage is a culprit as there are links between heavy social media and internet use and fewer friends and time spent with others. It is thought that time spent interacting with others online or passively consuming content is of lower quality than time spent with others in person.
Finally, some believe the COVID-19 pandemic may have affected friendships negatively. Due to lockdowns, social distancing, and health risks, people were forced to limit their physical contact with their friends and could have lost touch. However, data on the subject is limited and mixed as the pandemic affected different groups of people differently. Some people may have strengthened their friendships by sharing their vulnerabilities or by cutting out peripheral and superficial relationships.
Actions to combat the friendship recession
One study found that believing that friendship happens based on luck was related to more loneliness five years later, whereas believing that friendship takes effort was related to less loneliness.
See also
Third places
Hikkikomori
References
Friendship
Kindness
Philosophy of love
Social issues | Friendship recession | [
"Biology"
] | 847 | [
"Behavior",
"Human behavior",
"Kindness"
] |
75,080,123 | https://en.wikipedia.org/wiki/Non-exercise%20activity%20thermogenesis | Non-exercise activity thermogenesis (), also known as non-exercise physical activity (NEPA), is energy expenditure during activities that are not part of a structured exercise program. NEAT includes physical activity at the workplace, hobbies, standing instead of sitting, walking around, climbing stairs, doing chores, and fidgeting. Besides differences in body composition, it represents most of the variation in energy expenditure across individuals and populations, accounting from 6-10 percent to as much as 50 percent of energy expenditure in highly active individuals.
Relationship with obesity
NEAT is the main component of activity-related energy expenditure in obese individuals, as most do not do any physical exercise. NEAT is also lower in obese individuals than the general population.
NEAT may be reduced in individuals who have lost weight, which some hypothesize contributes to difficulties in achieving and sustaining weight loss.
In Western countries, occupations have shifted from physical labor to sedentary work, which results in a loss of energy expenditure. Strenuous physical labor can require 1500 calories or more per day than desk work.
Relationship with exercise
It is debated whether there is a significant reduction in NEAT after beginning a structured exercise program.
Health benefits
Lack of NEAT is posited as an explanation for health harms for prolonged sitting.
Measurement
Accelerometers and questionnaires can be used to estimate NEAT.
References
Human physiology
Metabolism | Non-exercise activity thermogenesis | [
"Chemistry",
"Biology"
] | 285 | [
"Biochemistry",
"Metabolism",
"Cellular processes"
] |
75,080,726 | https://en.wikipedia.org/wiki/Tartrolon | Tartrolons are a group of boron-containing macrolide antibiotics discovered in 1994 from the culture broth of the myxobacterium Sorangium cellulosum. Two variants of tartrolons, A and B, were identified. Tartrolon B contains a boron atom, while tartrolon A does not.
Discovery
In a study publishied in 1994, the producing organism, Sorangium cellulosum strain So ce 678, was isolated by a group of German scientists (Dietmar Schummer, Herbert Irschik, Hans Reichenbach, Gerhard Höfle) from a soil sample collected near Braunschweig in 1990, as antibiotics of the macrolide group. Synthesis was achieved by fermentation in the presence of the adsorber resin XAD-16. Adsorber resin is a type of synthetic polymer used to selectively extract and purify target molecules from solutions.
These findings were confirmed by a subsequent study, in 1995, where the strain was grown on a medium containing potato starch, yeast extract, defatted soja meal, glucose-H2O, MgSO4·7H2O, CaCl2-2H2O and Na-Fe(III)-EDTA at pH 7.2.
To isolate greater quantities of tartrolons for research purposes or potential applications in medicine, the strain was cultivated in a bioreactor. Cultivation was started with an inoculum grown in Erlenmeyer flasks under shaking at 30°C with an aeration rate of 0.15 m3 air per hour and a stirrer speed of 150 RPM.
Laboratory synthesis
The synthesis and regulation of tartrolons are influenced by the presence or absence of glass flasks during cultivation or by adding sodium tetraborate to the culture medium. When not exposed to glass or sodium tetraborate supplementation is absent, tartrolon A is predominantly produced; otherwise, tartrolon B becomes the main product.
Biological properties
Tartrolons have been found to inhibit Gram-positive bacteria similar to other related boron-containing antibiotics like boromycin and aplasmomycin, as their boron binding regions are identical. Tartrolons also show toxicity towards mammalian cell cultures.
Potential applications
The antimicrobial properties of tartrolons indicate they could be investigated as antibiotics to combat bacterial infections. However, more comprehensive studies are needed to ascertain their efficacy, safety, mechanism of action, and other potential medicinal uses; whether tartrolons possess selectivity towards enzymes or interference with energy delivery and membrane integrity; and whether tartrolons have any biological roles beyond their antibiotic activity in nature.
One potential application of tartrolons is the study of species such as Listeria monocytogenes. Listeria monocytogenes is a bacterium that can cause the infectious disease known as listeriosis. It is considered a foodborne pathogen and poses a significant risk to human health. Listeriosis primarily affects individuals with weakened immune systems, pregnant women, newborns, and the elderly. Listeria monocytogenes, as a bacterium, is present in diverse habitats where tartrolons are found. As such, it is important to explore the potential application of tartrolons in suppressing Listeria monocytogenes or other related pathogens. The antimicrobial properties exhibited by tartrolon B and its induction of the timABR locus, which contributes to resistance against tartrolons in Listeria monocytogenes, suggest their potential for antibacterial activities. However, additional studies would be needed to determine the specific effectiveness and mechanisms involved in controlling Listeria monocytogenes with tartrolons. Studying tartrolons may shed light on how pathogens like Listeria adapt to diverse habitats and survive within their ecological niches despite the presence of antimicrobial compounds produced by other microorganisms. Understanding these mechanisms could aid in developing strategies to control or prevent infections caused by Listeria or related pathogens. Besides the application in medicine, studying the interaction between Listeria monocytogenes and tartrolons may expose the broader ecological dynamics between bacteria in natural reservoirs such as soil and marine environments where both pathogenic and non-pathogenic species coexist. This knowledge can contribute to understanding of microbial ecology and can help design interventions to manage bacterial populations in agricultural settings or food production facilities where contamination with Listeria can occur.
References
Antibiotics
Boron | Tartrolon | [
"Biology"
] | 930 | [
"Antibiotics",
"Biocides",
"Biotechnology products"
] |
75,082,060 | https://en.wikipedia.org/wiki/294%20%28number%29 | 294 is the natural number following 293 and preceding 295.
In mathematics
294 is an even composite number with three prime factors.
294 is the number of planar biconnected graphs with 7 vertices. Biconnected graphs are two dimensional graphs with a given number of points and 294 is the number of ways to organize 7 vertices in different ways.
11115² - 294² = 123456789
The Magic Inscribed Lotus was created by Nārāyaṇa, and Indian Mathematician in the 14th century. In this inscription, each group of 12 numbers has a sum of 294. It was constructed with a 12 x 4 magic rectangle.
In 1930, George A. Miller determined that there are 294 isomorphic groups in the order of 64. Isomorphism is making a map that preserves relationships. This was later disproven as there are 267 isomorphic groups in the order of 64. See List of incomplete proofs.
References
Integers | 294 (number) | [
"Mathematics"
] | 186 | [
"Elementary mathematics",
"Integers",
"Mathematical objects",
"Numbers"
] |
75,082,176 | https://en.wikipedia.org/wiki/Institute%20of%20Telecommunications%20Professionals | The Institute of Telecommunications Professionals (ITP) is a membership organisation for professionals in the telecommunications industry, based in the United Kingdom.
The Institute was originally founded in 1906. It is now a registered company with Companies House in the United Kingdom, incorporated in 2002. Brendan O' Mahony has been the chief executive of the ITP.
Lucy Woods presided over ITP for fifteen years, until 2018, when the organization named Kevin Paige chairman for five years.
In 2019, the ITP established a new partnership with the Institution of Engineering and Technology (IET) with the aim of developing a joint professional registration scheme to elevate professional standards throughout the telecommunications industry.
In 2021, the ITP assisted a UK fibre network Vorboss in establishing its training academy. In 2023, the ITP appointed Tim Creswick, the CEO of Vorboss, as the new chair of its board of directors.
The institute has an associated journal, the Journal of the Institute of Telecommunications Professionals, established in 2007 and published quarterly.
See also
Telecommunications in the United Kingdom
Internet in the United Kingdom
References
External links
The ITP website
The Journal of the ITP
1906 establishments in the United Kingdom
Organizations established in 1906
Companies established in 2002
Telecommunications organisations in the United Kingdom
Organisations based in Surrey
Sunbury-on-Thames
Telecommunications | Institute of Telecommunications Professionals | [
"Technology"
] | 264 | [
"Information and communications technology",
"Telecommunications"
] |
75,082,412 | https://en.wikipedia.org/wiki/Eta2%20Fornacis | {{DISPLAYTITLE:Eta2 Fornacis}}
Eta2 Fornacis (η2 Fornacis) is an orange giant in the constellation of Fornax. The star has a spectral type of K0III and an apparent magnitude of 6.02. The star is visually close to, but unrelated with the similar stars η1 Fornacis and η3 Fornacis. The star is located at approximately 425 light years away, and forms a visual binary system with a 10th magnitude companion.
References
Fornax
Fornacis, Eta2
K-type giants
017829
0851
013265
Binary stars | Eta2 Fornacis | [
"Astronomy"
] | 131 | [
"Fornax",
"Constellations"
] |
66,362,975 | https://en.wikipedia.org/wiki/Insecure%20direct%20object%20reference | Insecure direct object reference (IDOR) is a type of access control vulnerability in digital security.
This can occur when a web application or application programming interface uses an identifier for direct access to an object in an internal database but does not check for access control or authentication. For example, if the request URL sent to a web site directly uses an easily enumerated unique identifier (such as http://foo.com/doc/1234), that can provide an exploit for unintended access to all records.
A directory traversal attack is considered a special case of an IDOR.
The vulnerability is of such significant concern that for many years it was listed as one of the Open Web Application Security Project’s (OWASP) Top 10 vulnerabilities.
Examples
In November 2020, the firm Silent Breach identified an IDOR vulnerability with the United States Department of Defense web site and privately reported it via the DOD's Vulnerability Disclosure Program. The bug was fixed by adding a user session mechanism to the account system, which would require authenticating on the site first.
It was reported that the Parler social networking service used sequential post IDs, and that this had enabled the scraping of terabytes of data from the service in January 2021. The researcher responsible for the project has said this was inaccurate.
References
Web security exploits
Hacking (computer security) | Insecure direct object reference | [
"Technology"
] | 283 | [
"Computer security stubs",
"Computing stubs",
"Computer security exploits",
"Web security exploits"
] |
66,363,156 | https://en.wikipedia.org/wiki/The%20Line%2C%20Saudi%20Arabia | The Line (stylised THE LINE; ) is a conceptual linear smart city in Saudi Arabia in Neom, Tabuk Province, housed in a single building, that is designed to have no cars, streets or carbon emissions. The original plans called for the city to span at a height of and a width of sized to accommodate a population of 9 million (25% of Saudi Arabia's 2022 population of 35.5 million). The Line would have an entirely glass mirror exterior. The plan calls for all basic services to be within a five-minute walking distance.
The plan was announced in 2021. Saudi Arabia has stated that it aims to complete a central segment by 2030, while completion of the full project has been pushed to 2045. However, in 2024, the Wall Street Journal and Bloomberg both reported that the first phase will only be 1.5 miles. Saudi officials denied these reports and stated that the project was continuing as planned.
The city is one of the five announced regions of Neom and is a part of Saudi Vision 2030 project.
Proposal
The Line is eventually planned to be long. It could stretch from the Red Sea approximately to the city of Tabuk and could have nine million residents, resulting in an average population density of . By comparison, Manila, the world's most densely populated city in 2020, had a density of . The Line's design consists of two mirrored buildings with an outdoor space in between, having a total width of and a height of . This would make it the third tallest building in the country after the Abraj Al-Bait Clock Tower and the Jeddah Tower, and approximately the 12th tallest building in the world.
The plan is for the city to be powered entirely by renewable energy. It will consist of three layers, one on the surface for pedestrians, one underground for infrastructure, and another underground for transportation. Artificial intelligence will monitor the city and use predictive and data models to find ways to improve daily life for its citizens, with residents being paid for submitting data to The Line.
The estimated building cost is US$100–200 billion (– billion SAR), with some estimates as high as $1 trillion. It is claimed by the Saudi government that it will create 460,000 jobs, spur economic diversification, and contribute 180 billion SAR (US$ billion) to domestic GDP by 2030. According to Crown Prince Mohammed bin Salman in 2022, the first phase project is expected to cost SAR 1.2 trillion (US$320 billion), and the Saudi sovereign wealth fund Public Investment Fund (PIF) would provide half of the sum.
On 5 April 2024, Bloomberg News reported that the project had been scaled back as a result of restrictions over funding by the PIF. Bloomberg cited Saudi officials as expecting a 2030 completion of a section of the city which would contain fewer than 300,000 residents, down from an expected 1.5 million.
Planning
The Line contains elements of architectural ideas from the industrial era.
In 1882, the Spanish urban planner Arturo Soria imagined a linear city, based on innovative use of the tramway. He applied part of his idea to a neighborhood in Madrid but lack of support ended the scheme.
In the 1950s, the French architect Yona Friedman proposed the concept of an integrated, modular and vertical "spatial city" to solve the problem of urban sprawl, but the idea remained an intellectual curiosity.
In the 1960s, the Italian avant-garde group Superstudio presented a radical artistic project: the continuous monument, "an architectural model for total urbanization," which was supposed to cover the entire Earth, but without any feasibility or real utility. The proposal was a criticism of Modernism, monumentality, design and capitalism.
The first plan for The Line was announced on 10 January 2021 by Saudi Crown Prince Mohammed bin Salman in a presentation broadcast on state television. Earthworks began in October 2021, and crews working on the project were to move in during 2024. , the first phase of the project was scheduled to be completed in 2030. Bin Salman, as chairman of the Neom board of directors, released a statement and promotional video on 25 July 2021 which led to more widespread media coverage of the project. This caused questions to be raised about the merits of the design and environmental issues, with critics concerned that the project would create a "dystopian" and "artificial" facility that had already displaced the Huwaitat indigenous tribe and would impact the migration of birds and wildlife.
Construction
By October 2022 construction was under way, with excavation taking place along the entire length of the project. Saudi Arabia commissioned a SAR 700-million (almost US$190-million) concrete multi-plant factory capable of producing up to 20,000 cubic meters (roughly 700,000 cubic ft) of concrete per day. By October 2024 over 100,000 workers were preparing the initial grading, working around the clock.
Architects
The project management required all architects to sign confidentiality agreements, which is why there are no references to The Line on any of their websites. German newspaper Süddeutsche Zeitung learned that two architects had terminated their participation in the project because of human rights and ecological concerns, Norman Foster and Francine Houben from Mecanoo. The paper also reported that several high-ranking architects were still on board, David Adjaye, Ben van Berkel (UN Studios), Massimiliano Fuksas, the London office of the late Zaha Hadid, Rem Koolhaas, the Laboratory for Visionary Architecture (LAVA) as well as Delugan Meissl and Wolf D. Prix from Coop Himmelb(l)au. The Süddeutsche criticized the lack of sustainability and the double standards of the architects in moral issues. In November 2024 it was announced that Delugan Meissl and Gensler had been appointed as the architects for phase one of the project.
Modules 40–50
By March 2023, more than 4,500 piles had been driven in module 43, reaching a peak of 60 piles per day. Piling work then shifted towards modules 45, 46 and 47 located at the marina. Excavation of about of earth was taking place each week at the marina.
The Hidden Marina
The design includes a marina, twice the size of existing marinas, on the northern side of the buildings, away from the sea. The plan calls for a tunnel and canal to be made through The Line, large enough for large cruise ships to pass through. Construction started in April 2022, aiming to open to visitors and residents by 2030. As of February 2024 over 90 million cubic metres of material had been moved.
The Spine
Early plans proposed an underground railway with trains that could travel from one end of The Line to the other in 20 minutes. As of 2023, short tunnels had been dug for the start of the railway and a train was in a prototype stage of development.
2024 scaling back
In April 2024 it was reported that the project had been "scaled back" after foreign direct investment investors had not "bought into the crown prince's vision", according to Torbjorn Soltvedt, principal analyst at risk consultancy Maplecroft. Fluctuating global oil prices had contributed to the decision.
The Line was expected to complete an initial section of long by 2030, with a population of 300,000 rather than the intended 1.5 million.
The Saudi minister of economy and planning rejected the claims of scaling back. He said in an interview during World Economic Forum special meeting in Riyadh that "For NEOM, the projects, the intended scale is continuing as planned. There is no change in scale". , Saudi Arabia intends to complete a central segment of The Line by 2030, while completion of the full project has been pushed to 2045.
Reception
Urban planning concerns
In an interview with Dezeen, associate professor Marshall Brown at Princeton University said he believed that in such large-scale urban planning, it would be difficult to achieve the slick, futuristic aesthetic seen in the concept art because of the large number of factors involved; for example, one of the images depicts a picnic on a ledge, which would probably be dangerous in real life. Hélène Chartier of C40 Cities compared The Line to other unrealised linear city projects, such as the 1882 design by Soria and a 1965 proposal for a linear settlement in New Jersey. Dutch architect Winy Maas said that while he would love to live in such an environment, its profile as seen in the concept art was monotonous, and he believed it would facilitate unfavorable wind flow through the interior.
Philip Oldfield of the University of New South Wales said that the quality of life would probably come down to whether the city was well-managed, rather than to its visual flair. Oldfield said the project would have a carbon footprint of about of equivalent in the glass, steel, and concrete, because "you cannot build a building out of low-carbon materials". He said the profile would create a large-scale barrier to adjacent ecosystems and migratory species similar to that created by highways, and the mirrored exterior facade would be dangerous for birds.
Researchers from the Vienna Complexity Science Hub suggested that a circular city of a radius would have had much shorter commuting times than a linear city. The average distance between two inhabitants of a linear city would be , as opposed to for a circular city. In a linear city, each inhabitant would have only 1.2% of the population in walking distance as "people are as far away from others as possible", as opposed to 24% in a circular city. In a linear city, walking and cycling would not be popular and travel time in a fast train would be disproportionately long, while a compact circular city would allow active mobility and fast trains would not be needed. The required density in a circular city would be much lower, which would allow it to be built with existing technology, reducing the environmental footprint of buildings. A railway line disruption would immobilize a linear city, but have less impact on a circular city.
Concerns about policy and human rights
Digital rights researchers such as Vincent Mosco have suggested that the city's data collection scheme could make it a "surveillance city", because of arrangements that would distort consent to sharing data, and because Saudi Arabia's poor human rights record might imply potential misuse of data. Neom CEO Joseph Bradley said that the Neom coordinators were resolving privacy issues and that Saudi Arabia had a personal data protection law.
Aside from the merits of the projected city, there was also scrutiny of the actions of the Saudi government in pursuing the project. In October 2022, three men of the Howeitat tribe, Shadli, Ibrahim, and Ataullah al-Huwaiti, were sentenced to death when they refused to vacate their village as part of the NEOM project. Shadli al-Huwaiti was the brother of Abdul Rahim al-Huwaiti, who was shot dead by security forces in April 2020 in his home in Al-Khariba, in the part of Tabuk province earmarked for NEOM, after he posted videos on social media opposing the displacement of local residents to make way for the project. In response to reports of human rights violations, one company, Solar Winds, pulled out of the project in 2022.
Feasibility
According to architect and urban planner Etienne Bou-Abdo, "the 3D images presented are not classical 3D architecture images", and the designers of the project "have rather called upon video game designers". Bou-Abdo stated that the plan included "a lot of technology that we don't have today". Many of the project's key announcements, particularly in the areas of energy and transportation, were based on technologies that did not exist even in prototype form.
See also
List of Saudi Vision 2030 Projects
Arcology
King Abdullah Economic City
Masdar City
Palm Islands
Prince Abdulaziz Bin Mousaed Economic City
Saudi–Egypt Causeway – proposed bridge over the Straits of Tiran from Saudi Arabia to Egypt
Jabal Omar development project
References
External links
(release date)
Saudi Arabia announces plans for the car-free linear city called The Line, 170 kilometers long as Part of Neom Project
(release date)
Neom
Planned communities in Saudi Arabia
Proposed populated places
Proposed special economic zones
Economy of Saudi Arabia
Special economic zones
2021 establishments in Saudi Arabia
Smart cities
Proposed arcologies | The Line, Saudi Arabia | [
"Technology"
] | 2,542 | [
"Exploratory engineering",
"Proposed arcologies"
] |
66,365,028 | https://en.wikipedia.org/wiki/Kit%20Miyamoto | Dr. Hideki "Kit" Miyamoto (born 1963) is a Japanese-American structural engineer known for being the founder-CEO of Miyamoto International, a global structural engineering and disaster risk reduction organization. He is also the chairman of California's Alfred E. Alquist Seismic Safety Commission, which investigates earthquakes and recommends policies for risk reduction.
Early life and education
Miyamoto was born and raised in Tokyo and studied earthquake engineering at the Tokyo Institute of Technology and California State University. He lives in Los Angeles.
Career
Miyamoto started his career in structural engineering and later focused on disaster resiliency, response, and reconstruction. He provides policy consultation to the World Bank, USAID, UN agencies, governments and private sector. He has led teams of professionals on response and reconstruction projects after the 2008 Sichuan earthquake, 2010 Haiti earthquake, 2011 Japan earthquake, 2015 Nepal earthquake, 2020 Puerto Rico earthquakes and other seismic risk reduction programs along with disaster risk mitigation policy work.
Miyamoto was elected as a chair of the California Seismic Safety Commission in October 2020. He has formerly served as a seismic safety commissioner for eight years where he has advocated for increased resiliency in California.
Innovations
Dr. Miyamoto was responsible for the seismic retrofit of the Theme Building, an iconic Space Age structure at Los Angeles International Airport (LAX). The innovative retrofit consisted of adding a tuned mass damper (TMD) to the top of the building's core. The TMD option was selected because it was less expensive, protected the building's architectural features, and minimized building closure. This was the first time this retrofit had been achieved in the United States.
Awards and recognitions
Earthquake Response
Dr. Kit Miyamoto plays a key role in earthquake damage assessment, building safety, capacity building, and reconstruction strategies to improve seismic resilience around the world. His work focuses on failure mechanisms and improved construction practices to reduce future earthquake risks.
Publications
Haiti earthquake 2021: Findings from the repair and damage assessment of 179,800 buildings, International Journal of Disaster Risk Reduction (2024)
Seismic Risk Assessment and Retrofit of School Buildings In Developing Countries, 11th U.S. National Conference on Earthquake Engineering, Los Angeles, California (2018)
Seismic Collapse Probability of Structures with Viscous Dampers per ASCE 7–16: Effect of Large Earthquake, 11th U.S. National Conference on Earthquake Engineering, Los Angeles, California (2018)
Damage Assessment and Seismic Retrofit of Heritage and Modern Buildings in the Aftermath of 2015 Nepal Earthquake, 11th U.S. National Conference on Earthquake Engineering, Los Angeles, California (2018)
Design of Structures with Dampers per ASCE 7–16 and Performance for Large Earthquakes, Structures Congress, Houston, Texas (2018)
Cost-Effective Seismic Isolation Retrofit of Heritage Cathedrals in Haiti, 16th World Conference on Earthquake, Santiago, Chile (2017)
Transparent Global Earthquake Risk And Loss Estimation, Tokyo, Japan (2013)
Media
Major media such as CNN, LA Times, NY Times and Rolling Stone have mentioned, represented, or interviewed him. He was also featured in the “Designing for Disaster” exhibit at the National Building Museum.
References
Structural engineers
Earthquake engineering
1963 births
Living people | Kit Miyamoto | [
"Engineering"
] | 659 | [
"Earthquake engineering",
"Civil engineering",
"Structural engineering",
"Structural engineers"
] |
66,366,903 | https://en.wikipedia.org/wiki/Simon%20Greenhill | Simon James Greenhill is a New Zealand scientist who works on the application of quantitative methods to the study of cultural evolution and human prehistory. He is well known for creating and building various linguistics databases, including the Austronesian Basic Vocabulary Database, TransNewGuinea.org, Pulotu, and many others. In addition to Austronesian, he has contributed to the study of the phylogeny of many language families, including Dravidian and Sino-Tibetan.
He is a graduate of University of Auckland, New Zealand. The title of his 2008 doctoral thesis is The archives of history: a phylogenetic approach to the study of language.
Greenhill is currently a scientist affiliated with the Australian National University in Canberra, Australia, and the Max Planck Institute for the Science of Human History in Jena, Germany.
References
External links
Austronesian Basic Vocabulary Database
Trans-New Guinea Online
POLLEX: Polynesian Lexicon Project Online
Pulotu, Database of Pacific Religions
Database of Places, Language, Culture and Environment (D-PLACE)
Profiles
Australian National University
Google Scholar
ResearchGate
Computational linguistics researchers
Linguists of Austronesian languages
University of Auckland alumni
Academic staff of the Australian National University
Living people
Year of birth missing (living people)
Max Planck Institute for the Science of Human History
Phylogenetics researchers | Simon Greenhill | [
"Biology"
] | 260 | [
"Phylogenetics",
"Phylogenetics researchers"
] |
66,366,941 | https://en.wikipedia.org/wiki/Pollux%20Temple | Pollux Temple is a summit in the Grand Canyon, in Coconino County of northern Arizona, US. It is situated ten miles northwest of Grand Canyon Village, and less than one mile northeast of Jicarilla Point. Castor Temple is one mile northwest, and Diana Temple is one mile southeast. Topographic relief is significant as Pollux Temple rises nearly above the Colorado River in less than two miles. Pollux Temple is named for Pollux, the divine son of Zeus according to Greek mythology. Clarence Dutton began the practice of naming geographical features in the Grand Canyon after mythological deities. According to the Köppen climate classification system, Pollux Temple is located in a Cold semi-arid climate zone.
Geology
The top of Pollux Temple is composed of Permian Toroweap Formation overlaying cream-colored, cliff-forming, Permian Coconino Sandstone. The sandstone, which is the third-youngest of the strata in the Grand Canyon, was deposited 265 million years ago as sand dunes. Below the Coconino Sandstone is reddish, slope-forming, Permian Hermit Formation, which in turn overlays the Pennsylvanian-Permian Supai Group. Further down are strata of the conspicuous cliff-forming Mississippian Redwall Limestone, the Cambrian Tonto Group, and finally granite of the Paleoproterozoic Vishnu Basement Rocks at river level in Granite Gorge. Precipitation runoff from Pollux Temple drains north to the Colorado River via Agate and Sapphire Canyons.
Gallery
See also
Geology of the Grand Canyon area
Scorpion Ridge
References
External links
Weather forecast: National Weather Service
Pollux Temple from Piute Point: Flickr photo
Pollux Temple photo by Harvey Butchart
Grand Canyon
Landforms of Coconino County, Arizona
Mountains of Arizona
Mountains of Coconino County, Arizona
Colorado Plateau
Grand Canyon National Park
One-thousanders of the United States
Grand Canyon, South Rim
Grand Canyon, South Rim (west)
Castor and Pollux | Pollux Temple | [
"Astronomy"
] | 393 | [
"Castor and Pollux",
"Astronomical myths"
] |
66,366,977 | https://en.wikipedia.org/wiki/FM%20Circini | FM Circini, also known as Nova Circini 2018, was a nova which appeared in the constellation Circinus (near the boarder with Musca) in 2018. It was discovered by John Search of Chatsworth Island, New South Wales, Australia on 19.708 January 2018, using a DSLR with a 50 mm F/1.2 lens. At the time of its discovery, it had an apparent visual magnitude of 9.1. It was confirmed to be a nova spectroscopically on 21 January 2018. FM Circini reached a peak brightness of magnitude 5.8 on 22 March 2018, making it visible to the naked eye.
FM Circini's outburst and decline from peak brightness was observed by the Gaia spacecraft, the All Sky Automated Survey for SuperNovae and AAVSO observers. The nova rose slowly to peak brightness, and then fluctuated between magnitude ~6.5 and ~8.5 for about three months, before beginning a nearly monotonic decline. It took 150 days for FM Circini to fade from peak brightness by 2 magnitudes, which makes it a "slow" nova in the classification scheme of Cecilia Payne-Gaposchkin.
The orbital period of FM Circini is 3.4898 days. The lightcurve shows modulations in the tail (after the eruption).
External links
Photograph of FM Circini taken on 10 March 2018
References
Novae
Circinus
Astronomical objects discovered in 2018
Circinus, FM | FM Circini | [
"Astronomy"
] | 311 | [
"Novae",
"Circinus",
"Astronomical events",
"Constellations"
] |
66,367,117 | https://en.wikipedia.org/wiki/Materials%20Project | The Materials Project is an open-access database offering material properties to accelerate the development of technology by predicting how new materials–both real and hypothetical–can be used. The project was established in 2011 with an emphasis on battery research, but includes property calculations for many areas of clean energy systems such as photovoltaics, thermoelectric materials, and catalysts. Most of the known 35,000 molecules and over 130,000 inorganic compounds are included in the database.
Dr. Kristin Persson of Lawrence Berkeley National Laboratory founded and leads the initiative, which uses supercomputers at Berkeley, among other institutions, to run calculations using Density Functional Theory (DFT). Commonly computed values include enthalpy of formation, crystal structure, and band gap. The assembled databases of computed structures and properties is freely available to anyone under a CC 4.0 license and was developed with ease of use in mind. The data have been used to predict new materials that should be synthesizable, and screen existing materials for useful properties.
The project can be traced back to Persson's postdoc research at MIT in 2004, during which she was given access to a supercomputer to do DFT calculations. After joining Berkeley Lab in 2008, Persson received the necessary funding to make the data from her research freely available.
References
Materials science
Internet properties established in 2011
Scientific databases | Materials Project | [
"Physics",
"Materials_science",
"Engineering"
] | 282 | [
"Materials science stubs",
"Applied and interdisciplinary physics",
"Materials science",
"nan"
] |
66,367,931 | https://en.wikipedia.org/wiki/Spatial%20embedding | Spatial embedding is one of feature learning techniques used in spatial analysis where points, lines, polygons or other spatial data types. representing geographic locations are mapped to vectors of real numbers. Conceptually it involves a mathematical embedding from a space with many dimensions per geographic object to a continuous vector space with a much lower dimension.
Such embedding methods allow complex spatial data to be used in neural networks and have been shown to improve performance in spatial analysis tasks
Embedded data types
Geographic data can take many forms: text, images, graphs, trajectories, polygons. Depending on the task, there may be a need to combine multimodal data from different sources. The next section describes examples of different types of data and their uses.
Text
Geolocated posts on social media can be used to acquire a library of documents bound to a given place that can be later transformed to embedded vectors using word embedding techniques.
Image
Satellites and aircraft collect digital spatial data acquired from remotely sensed images which can be used in machine learning. They are sometimes hard to analyse using basic image analysis methods and convolutional neural networks can be used to acquire an embedding of images bound to a given geographical object or a region.
Point
A single point of interest (POI) can be assigned multiple features that can be used in machine learning. These could be demographic, transportation, meteorological, or economic data, for example. When embedding single points, it is common to consider the entire set of available points as nodes in a graph.
Line / multiline
Among other things, motion trajectories are represented as lines (multilines). Individual trajectories are embedded taking into account travel time, distances and also features of points visited along the way. Embedding of trajectories allows to improve performance of such tasks as clustering and also categorization.
Polygon
The geographic areas analyzed in machine learning are defined by both administrative boundaries and top-down division into grids of regular shapes such as rectangles, for example. Both types are represented as polygons and, like points, can be assigned different demographic, transportation, or economic features. A polygon can also have features related to the size of the area or shape it represents.
Graph
An example domain where graph representation is used is the street layout in a city, where vertices can be intersections and edges can be roads. The vertices can also be destination points like public transport stops or important points in the city, and the edges represent the flow between them. Embedding graphs or single vertices allows to improve accuracy of analysis methods in which the treated geographical domain can be represented as a network.
Usage
POI recommendation - generating personalized point of interest recommendations based on user preferences.
Next/future location prediction - prediction of the next location a person will go to based on their historical trajectory.
Zone functions classification - based on different mobility of people or POI distribution a function of a given area in a city can be predicted.
Crime prediction - estimation of crime rate in different regions of a city.
Local event detection - studying spatio-temporal changes in embeddings can provide valuable information in detection of local event occurring in specific location.
Regional mobility popularity prediction - analysis of mobility can show patterns in popularity of different regions in a city.
Shape matching - finding a similar shape of given polygon, for example finding building with the same shape as input building.
Travel time estimation - predicting estimated travel time given current traffic conditions and special occurring events.
Time estimation for on-demand food delivery - estimation of delivery time when placing an order through the website.
Temporal aspect
Some of the data analyzed has a timestamp associated with it. In some cases of data analysis this information is omitted and in others it is used to divide the set into groups. The most common division is the separation of weekdays from weekends or division into hours of the day. This is particularly important in the analysis of mobility data, because the characteristics of mobility during the week and at different times of the day are very different from each other. Another area in which time division into, for example, individual months can be used is in the analysis of tourism of a given region. In order to take such a split into account, embedding methods treat the time stamp specifically or separate versions of the model are developed for different subgroups of the analyzed set.
References
Machine learning
Data mining
Spatial analysis | Spatial embedding | [
"Physics",
"Engineering"
] | 900 | [
"Machine learning",
"Spatial analysis",
"Space",
"Artificial intelligence engineering",
"Spacetime"
] |
66,368,969 | https://en.wikipedia.org/wiki/Virtual%20influencer | A virtual influencer, at times described as a virtual persona or virtual model, is a computer-generated fictional character that can be used for a variety of marketing-related purposes, but most frequently for social media marketing, in lieu of online human "influencers". Most virtual influencers are designed using computer graphics and motion capture technology to resemble real people in realistic situations. Common derivatives of virtual influencers include VTubers, which broadly refer to online entertainers and YouTubers who represent themselves using virtual avatars instead of their physical selves.
History
Virtual influencers are fundamentally synonymous with virtual idols, which originate from Japan's anime and Japanese idol culture that dates back to the 1980s. The first virtual idol created was Lynn Minmay, a fictional singer and main character of the anime television series Super Dimension Fortress Macross (1982) and the animated film adaptation Macross: Do You Remember Love? (1984). Minmay's success led to the production of more Japanese virtual idols, such as EVE from the Japanese cyberpunk anime Megazone 23 (1985), and Sharon Apple in Macross Plus (1994). Virtual idols were not always well received – in 1995, Japanese talent agency Horipro created Kyoko Date, which was inspired by the Macross franchise and dating sim games such as Tokimeki Memorial (1994). Date failed to gain commercial success despite drawing headlines for her debut as a CGI idol, largely due to technical limitations leading to issues such as unnatural movements, an issue also known as the uncanny valley.
Since their inception, many virtual idols created have achieved continual success, with notable names including the Vocaloid singer Hatsune Miku, and the virtual YouTuber Kizuna AI. Technological advancements have also enabled production teams to use artificial intelligence and advanced techniques to customize the personalities and behavior of virtual idols.
Benefits
From a branding perspective, virtual influencers are much less likely to be mired in scandals. In China, celebrities caught in bad publicity such as singer Wang Leehom and entertainer Kris Wu have heightened the appeal of virtual influencers, since their existence relies entirely on computer-generated imagery, and hence are unlikely to cause any damage to a brand's image by association. Some studies have also suggested that Generation Z consumers have a unique appetite for virtual idols and influencers, since they grew up in the age of the internet. Studies also show that human-like appearance of virtual influencers show higher message credibility than anime-like virtual influencers.
Notable examples
Virtual bands
Eternity - A South Korean virtual idol group formed by Pulse9.
Gorillaz - A virtual band formed in 1998.
K/DA - A virtual K-pop girl group created as part of the League of Legends video game franchise.
MAVE: - A South Korean virtual girl group formed in 2023 by Metaverse Entertainment.
Pentakill - A virtual heavy metal band created as part of the League of Legends video game franchise.
Plave (band) - A South Korean virtual boy band formed by VLast.
Squid Sisters and Off the Hook - Two virtual pop idol duos as part of the Splatoon series.
Studio Killers - A Finnish-Danish-British virtual band formed in 2011.
Vocaloids
Hatsune Miku (modeled after Saki Fujita)
Kagamine Rin/Len (modeled after Asami Shimoda)
Megurine Luka (modeled after Yū Asakawa)
Meiko (modeled after Meiko Haigō)
Kaito (modeled after Naoto Fūga)
VTubers
Kano
Kizuna AI
Neuro-sama
VShojo
Ironmouse
Projekt Melody
Nijisanji
Hololive
Akai Haato
Gawr Gura
Hoshimachi Suisei
Natsuiro Matsuri
Other examples
Ami Yamato
Crazy Frog
FN Meka
IA
Kuki AI
Kyoko Date
Kyra
Miquela
Naevis
Shudu Gram
See also
Avatar (computing)
CGI
Content creation
Internet celebrity
Uncanny valley
Virtual actor
Virtual band
Virtual character
Virtual human
References
Internet celebrities
Internet culture
Cyberpunk themes
Social media | Virtual influencer | [
"Technology"
] | 826 | [
"Computing and society",
"Social media"
] |
66,369,269 | https://en.wikipedia.org/wiki/BiP%20%28software%29 | BiP is a freeware instant messaging application developed by Lifecell Ventures Cooperatief U.A., a subsidiary of Turkcell incorporated in the Netherlands. It allows users to send text messages, voice messages and video calling, and it can be downloaded from the App Store, Google Play, and Huawei AppGallery. BiP has over 53 million users worldwide, and was first released in 2013.
Functions
BiP is a secure, and free communication platform. BiP allows making video and audio calls, allows sharing images, videos and location. BiP includes instant translations to 106 languages and exchange rates. President Erdoğan's Communications Office opposed WhatsApp's enforcement of its updated privacy policy and announced that Erdoğan left WhatsApp and opened an account in Telegram and BiP. The Turkish Ministry of National Defense has announced that it will move information groups to BiP for the same reason.
Others
Banglalink announced a BiP messenger partnership in Bangladesh The Communications Office of President Erdoğan opposed WhatsApp's enforcement of its updated privacy policy and announced that Erdoğan left WhatsApp and opened an account in Telegram and BiP. The Turkish Ministry of National Defense has announced that it will move information groups to BiP for the same reason.
The CEO of BiP is Burak Akinci.
The number of downloads of the app is 80 million globally.
See also
Comparison of instant messaging clients
Comparison of VoIP software
List of most-downloaded Google Play applications
Comparison of user features of messaging platforms
References
Instant messaging clients
Mobile applications
2013 software
Turkish brands
Android (operating system) software
IOS software
Social media
VoIP software
Cross-platform software
Communication software
Software companies of Turkey | BiP (software) | [
"Technology"
] | 346 | [
"Instant messaging",
"Computing and society",
"Instant messaging clients",
"Social media"
] |
66,369,603 | https://en.wikipedia.org/wiki/Plutonium%28III%29%20bromide | Plutonium(III) bromide is an inorganic salt of bromine and plutonium with the formula PuBr3. This radioactive green solid has few uses, however its crystal structure is often used as a structural archetype in crystallography.
Crystal structure
The PuBr3 crystal structure was first published in 1948 by William Houlder Zachariasen. The compound forms orthorhombic crystals, a type of square antiprism, within which the Pu atoms adopt an 8-coordinate bicapped trigonal prismatic arrangement. Its Pearson symbol is oS16 with the corresponding space group No. 63 (in International Union of Crystallography classification) or Cmcm (in Hermann–Mauguin notation). The majority of trivalent chloride and bromide salts of lanthanide and actinides crystallise in the PuBr3 structure.
References
Plutonium(III) compounds
Actinide halides
Crystal structure types | Plutonium(III) bromide | [
"Chemistry",
"Materials_science"
] | 190 | [
"Crystallography",
"Inorganic compounds",
"Crystal structure types",
"Inorganic compound stubs"
] |
66,369,801 | https://en.wikipedia.org/wiki/Toloka | Toloka, based in Amsterdam, is a crowdsourcing and generative AI services provider.
The company helps development of artificial intelligence from training to evaluation and provides generative artificial intelligence and large language model-related services.
History
Toloka was founded in 2014 by Olga Megorskaya, a member of the board of directors of Yandex, as a crowdsourcing and microtasking platform. It was founded primarily for data markup to improve machine learning and search algorithms
As generative AI evolved, the platform adapted to provide expert data labeling to generational AI app producers.
In 2024, the company's Russian operations were sold to Russian investors.
Services
Generative AI
In the generative AI domain, Toloka provides services such as model fine tuning, reinforcement learning from human feedback, evaluation, adhoc datasets, which require large volumes of highly skilled experts annotation.
Machine learning
On Toloka, trainers are tasked with identifying the presence or absence of objects in content, as specified by algorithms. They also assess chatbot responses within given dialogues for relevance and engagement. Additionally, translation verification tasks involve evaluating the accuracy of translations from multiple annotators. For the fine-tuning of large language models (LLMs), experts are required to generate and provide context-based prompts that can be single-turn or multi-turn, serving various domains and purposes.
Natural language processing
In the natural language processing (NLP) domain, Toloka facilitates optical character recognition and classification, sentiment analysis, named-entity recognition, and search relevance evaluation. It also provides transcription and classification of audio data.
Annotators
Toloka mainly works with domain experts, such as physicists, scientists, lawyers, and software engineers, to develop specialized data for models targeting niche tasks. Toloka also works with freelancers, referred to as "Tolokers," who annotate and create data for diverse applications. They perform tasks such as labeling personally identifiable information for AI projects, translating content, summarizing information, and transcribing audio to text.
Upon completion of each task the performer receives a reward based on the volume of images, videos, and unstructured text.
Research
In May 2019, Toloka's research team began publishing datasets for non-commercial and academic purposes to support the scientific community and attract researchers to Toloka. Such datasets are addressed to researchers in different directions like linguistics, computer vision, testing of result aggregation models, and chatbot training.
Toloka research has been showcased at a range of conferences, including the Conference on Neural Information Processing Systems (NeurIPS), the International Conference on Machine Learning (ICML) and the International Conference on Very Large Data Bases (VLDB).
In February 2024, Toloka conducted a tutorial at the AAAI Conference on Artificial Intelligence, focusing on aligning Large Language Models to Low-Resource Languages.
The company participated in BigCode, a joint scientific initiative led by HuggingFace and ServiceNow, where it served as the primary data partner.
Controversies
Enabling arrests of protesters via facial recognition software (March 2024)
In March 2024, Toloka's Russian division was criticized for helping develop the facial recognition software used by Russia to track and arrest protesters after the death of Alexei Navalny. The company's Russian operations were sold in July 2024.
References
External links
Companies based in Amsterdam
Crowdsourcing
Human-based computation
Social information processing
Web services | Toloka | [
"Technology"
] | 713 | [
"Information systems",
"Human-based computation"
] |
66,370,248 | https://en.wikipedia.org/wiki/KOI-5 | KOI-5 is a triple star system composed of three stars: KOI-5 A, KOI-5 B and KOI-5 C, orbiting 1,870 light-years away.
The two dim stellar companions to KOI-5A were discovered in 2016. KOI-5 A and B orbit each other every 29 years, and KOI-5 C orbits stars A and B every 400 years. KOI-5C is physically associated with the core stellar pair with probability 99.98%.
Planetary system
Two planets orbiting one of KOI-5's stars were suspected since 2009 based on Kepler data, but KOI-5Ab was confirmed only in January 2021 after TESS determined the planet is orbiting KOI-5A. The exoplanet has caused interest in the scientific community because its orbital plane is misaligned with the closer star, suggesting it gave KOI-5Ab a gravitational kick during its development, resulting in the misalignment and inward migration to the current orbit. However, the confirmation of this planet has yet to be published in any peer-reviewed journal.
A second candidate planet was initially suspected, but was later found to be a false positive.
References
Cygnus (constellation)
G-type main-sequence stars
0005
Planetary systems with one confirmed planet
J19185753+4438507
Triple star systems
Planetary transit variables | KOI-5 | [
"Astronomy"
] | 286 | [
"Cygnus (constellation)",
"Constellations"
] |
66,370,966 | https://en.wikipedia.org/wiki/Israel%20Police%20Bomb%20Disposal%20Unit | The Israel Police Bomb Disposal Unit () is a section of the Israel National Police tasked with render-safe operations, recovery, disposal of explosive devices and processing crime scenes after bombing incidents. An Israeli police officer trained in bomb disposal is called "Chablan" (in Hebrew: חבלן).
Mission and tasks
The unit is tasked with handling a variety of tasks. These include inspection and examination. of suspicious objects, render-safe procedures of IEDs, military explosive ordnance and unexploded ordnance.
Stations of the unit are located in the major cities and in districts which cover different regions of Israel.
The Israel Border Police operates similar units which conduct similar tasks in the Judea and Samaria Area.
Personnel
Personnel of the bomb disposal unit are police officers which have usually served previously in combat or engineering units of the Israel Defence Force.
Ranks and insignia
Personnel of the Israel Police Bomb Disposal Unit are permitted to wear the unit's symbol as a badge on their uniform.
The symbol consists of:
The emblem of the Israel Police in the center.
A pair of olive branches on both sides as a symbol of security and peace.
A pair of lightning bolts to symbolise the explosive effects during a neutralisation of an explosive device.
Red background as symbol of a unit which operates in hazardous environments.
The unit's symbol can also be found on vehicles and on equipment.
Equipment
Bomb suits
ANDROS police robot
Bomb containment chambers on vehicles
Barrett M82 Anti-materiel rifle
Further reading
References
External links
Bomb disposal
Police units of Israel | Israel Police Bomb Disposal Unit | [
"Chemistry"
] | 311 | [
"Explosion protection",
"Bomb disposal"
] |
66,373,531 | https://en.wikipedia.org/wiki/Taphrina%20tosquinetii | Taphrina tosquinetii is a fungal plant pathogen that causes large blisters on both surfaces of the leaves of alder.
Description of the gall
The ascomycete induces a gall that distorts the leaves of alder. The leaves are slightly thickened, brittle and incurved with blister-like growth on both sides, which can increase the size of an infected leaf to twice the normal size. Later the leaf tissue becomes pale and thin with a whitish bloom when the asci develop. Species infected include common alder (Alnus glutinosa), grey alder (Alnus incana) and Alnus x pubescens.
References
Taphrinomycetes
Fungi described in 1866
Fungi of Europe
Galls
Taxa named by Edmond Tulasne
Fungus species | Taphrina tosquinetii | [
"Biology"
] | 167 | [
"Fungi",
"Fungus species"
] |
66,373,584 | https://en.wikipedia.org/wiki/Zerologon | Zerologon (formally: ) is a privilege elevation vulnerability in Microsoft's authentication protocol Netlogon Remote Protocol (MS-NRPC) , as implemented in the Windows Client Authentication Architecture and Samba.
The vulnerability was first reported to Microsoft by security researcher Tom Tervoort from Secura on 17 August 2020 and dubbed "Zerologon". Zerologon was given a Common Vulnerability Scoring System v3.1 severity ranking of 10 by the U.S. American National Institute of Standards and Technology and a 5.5 by Microsoft. Crowdstrike classifies it as the most severe Active Directory vulnerability of 2020.
The vulnerability allows from an unauthenticated user of the network to establish an unsafe conncetion to a Domain Controller (DC) and further impersonate the DC to elevate to domain admin priviledges. It allows attackers to access all valid usernames and passwords in each Microsoft network that they breached. This in turn allows them to access additional credentials necessary to assume the privileges of any legitimate user of the network, which in turn can let them compromise Microsoft 365 email accounts.
Background
The Netlogon Remote Protocol (MS-NRPC) is a Microsoft protocol used for authentication and secure communication between clients and DCs in a Windows network environment. It facilitates the exchange of authentication data and the establishment of secure channels for communication, enabling clients to authenticate against Active Directory and other network services. The protocol plays a key role in domain join operations, password changes, and other security-related tasks within a Windows domain.
Behavior
The original report by Secura explains the exploit in five steps.
Bypassing the authentication
The attack focuses on the DC of a network. MS-NRPC relies on a challenge–response authentication to generate a session key from the shared secret (such as a passphrase). To authenticate a client, the MS-NRPC client credentials are computed from the session key, an initialization vector (IV), and the client challenge using a less common Advanced Encryption Standard (AES) block cipher mode, namely 8-bit Cipher Feedback Mode (AES-CFB8) . This is, where the vulnerability lies. Due to the randomly chosen server secret, the computations of the session key yield in 1 out of 256 cases a session key that begins with a zero-byte. The session key is then used to encrypt the IV and the client challenge. Since the IV is all-zero by default, the client challange can be set to an all-zero vector as well and zero-byte beginning of the session key, AES-CFB8 results in an all-zero client credential. The server computed client credentials are then compared to the client sent credentials, which an attacker has also set to all-zero. The client is now authenticated.
Disabling signing and encryption
To circumvent signing and encryption with the session key (which the attacker does not know) that is performed by MS-NRPC, an attacker can disable it by not setting a flag in the authentication RPC call.
Spoofing RPC calls
Another obstacle the attacker must overcome is the so-called authenticator value used by Netlogon, that is required for some calls. This value is computed from an incrementing value held by the client, the client credentials, and a timestamp. If the incrementing value is set to all-zero by the client and the timestamp is also set to all-zero when an RPC call is invoked, the server will set the authenticator to all-zero as well, allowing the attacker to carry out the call.
Setting the password
In the penultimate step, the password is set to an empty one, allowing the attacker to follow the normal protocol procedure from this point on.
Elevating to domain admin
It is possible for the attacker to impersonate not just any user on the domain, but the domain controller itself. Once logged in, the attacker can retrieve hashed credentials from the DC, enabling a Pass the hash attack and ultimately elevating to the domain administrator.
Mitigation
Microsoft addressed the Zerologon vulnerability through two security updates. A less strict one in August 2020 and a later one in February 2021 that enforces signing and encryption for MS-NRPC calls by default, with the ability to allow certain devices to handle legacy support.
Response and impact
In 2020, Zerologon started to be used by sophisticated cyberespionage campaigns of threat groups such as Red Apollo in global attacks against the automotive, engineering and pharmaceutical industry. Zerologon was also used to hack the Municipal wireless network of Austin, Texas.
Unusually, Zerologon was the subject of an emergency directive from the United States Cybersecurity and Infrastructure Security Agency.
See also
2020 United States federal government data breach
References
2020 in computing
Computer security exploits | Zerologon | [
"Technology"
] | 996 | [
"Computer security exploits"
] |
66,373,900 | https://en.wikipedia.org/wiki/Girardin%20Jean-Louis | Girardin Jean-Louis is an American academic who is a Professor in the Departments of Psychiatry and Neurology at the University of Miami, Miller School of Medicine. He serves as Director of the Translational Sleep and Circadian Sciences Program and the "Program to Increase Diversity among Individuals Engaged in Health-Related Research" (PRIDE BSM) Institute. Dr. Jean-Louis’ translational behavioral sleep and circadian research was recently featured in Science and NPR. In 2020, he was named ‘Pioneer in Minority Health and Health Disparities’ and one of the Community of Scholars' most inspiring Black scientists in America. In 2021, he received the Mary A. Carskadon Outstanding Educator Award from the Sleep Research Society, and in 2022 the Diversity, Equity, and Inclusion Leadership Award from the American Academy of Sleep Medicine.
Early life and education
Jean-Louis grew up in Haiti. He became interested in engineering as a child, and particularly enjoyed building different contraptions. At the age of seventeen he immigrated to New York City, where he joined the City College of New York as an undergraduate student in engineering. As a student he took an elective course in sleep lab techniques, and became interested in sleep and wakefulness. He earned his doctoral degree at the Graduate Center of the City University of New York. His doctoral research considered the impact of melatonin on sleep and cognition in elderly individuals. He was a postdoctoral research associate at the University of California, San Diego, where he specialized in sleep and chronobiology. As part of his research, Jean-Louis advanced the science around wearable technologies (actigraphy) to monitor patient's sleep-wake behavior out of hospital and expensive laboratories. In the early days of his research on sleep science, Jean-Louis struggled to find academic mentors, particularly mentors of color. He continued to improve the science of actigraphy such that it could be more readily used to collect sleep data in the comfort and safety of patient's own home.
Research and career
Jean-Louis studies the sociocultural and environmental determinants of health. His research considers sleep medicine and health equity, an in particular, how low-income and minority communities are impacted by insufficient sleep. He is particularly interested in why sleep apnea is under-diagnosed in African-Americans. In 2008, he showed that less than 40% of African-American patients with sleep apnea agreed to having a diagnostic test. In an effort to understand the sleep behavior of minority groups, Jean-Louis has led several outreach initiatives. These include programs in churches, barber shops and health salons.
Jean-Louis was awarded an National Institute on Aging (NIA) Leadership Career Award in 2018. In 2020, he was selected as one of The Community of Scholars' most inspiring Black scientists in America. Alongside his academic research, Jean-Louis has launched several initiatives to support underrepresented minority groups in science and medicine. As the satisfaction and medical outcomes of communities of color are impacted by the racial/ethnic heritage of the physician, Jean-Louis believes there is an urgent need for more diverse medical practitioners.
Selected publications
References
Year of birth missing (living people)
Living people
American people of Haitian descent
CUNY Graduate Center alumni
City College of New York alumni
New York University faculty
American psychiatrists
Psychiatry academics
Sleep researchers | Girardin Jean-Louis | [
"Biology"
] | 672 | [
"Sleep researchers",
"Behavior",
"Sleep"
] |
66,374,046 | https://en.wikipedia.org/wiki/Cucumis%20trilobatus | Cucumis trilobatus may refer to one of two separate species:
Cucumis ficifolius (Cucumis trilobatus Forssk)
Cyclanthera pedata (Cucumis trilobatus L.) | Cucumis trilobatus | [
"Biology"
] | 56 | [
"Set index articles on plants",
"Set index articles on organisms",
"Plants"
] |
66,374,203 | https://en.wikipedia.org/wiki/Walter%20Baily%27s%20Motor | Walter Bailys Polyphase motor (1879) marks the beginning of the development of modern polyphase motors. Mr. Bailey exhibited his invention on the Physical Society of London on June 28, 1879, on the occasion of his reading a paper entitled, "A Mode of Producing Arago's Rotations."
Description
Before Baily's invention, the only mode of producing the Arago-rotations of a copper disk had been by rotating beneath it a steel magnet. Baily, instead of rotating any material magnet below the disk used a fixed electromagnet, but caused its magnetism to shift progressively between four successive poles, thus producing in the copper disk pivoted above the eddy-currents, which by their reaction gave the disk a mechanical motion in the direction of the progression of the poles.
The disk in this primitive model is about inches in diameter; the four magnet cores are about 4 inches high, joined to a common yoke; and each is wound with about 150 turns of insulated copper wire 2,5 mm in diameter. The coils are connected two and two in series, like two independent horseshoe magnets set diagonally across one another. The two circuits are brought down separately to an ingenious revolving commutator built up of a simple arrangement of springs and contact strips mounted on a bit of wood, with a wire handle by which it is turned. On rotating it, the currents from two batteries are caused to be reversed alternately in the two circuits, giving rise to the following successions of polarity in the four poles and so forth.
Baily's view on rotating magnetic field
Mr. Baily had very clear views as to how far this really represented a rotatory magnetic field. His own words are as follows:"The rotation of the disk is due to that of the magnetic field in which it is suspended; and we should expect that if a similar motion of the field could be produced by any other means the result would be a similar motion of the disk."
"Possibly the rotation of the magnet may be the only practicable way of producing a uniform rotation of the field; but it will be shown in this paper that the disk can be made to rotate by an intermittent rotation of the field effected by means of electromagnets."The author then goes on to discuss the result of the increase in strength of a pole while a neighboring pole of the same sign decreases in strength, and suggests that if a whole circle of poles were arranged under the disk, and successively excited in opposite pairs, the series of impulses all tend to make the disk move in one direction around the axis; adding:"In one extreme case, viz. when the number of electromagnets is infinite, we have the case of a uniform rotation of the magnetic field, such as we obtain by rotating permanent magnets."He then returns to the case of his actual model with two pairs of poles a a' and b b' and points out that if the b b' pair are arranged to be reversed before the a a' pair, the rotation will be in one direction; whilst, if the b b' pair are reversed after the a a' pair the rotation will take place in the other direction. He goes on to show how the reversal of the direction of rotation may be effected either by reversing the action of the commutator, or by reversing the connections of one of the two batteries. The diagram accompanying the original paper suggests that the cores should be of laminated iron; but those of the actual model are solid. In a final paragraph the author remarks that the effect on the disk might be much increased by placing four other electromagnets above the disk, each opposite one of the lower magnets, and connected with it so as to present an opposing polarity.
The model runs exceedingly well when four dry cells are used to excite the electromagnets.
On the occasion, when the paper was read and the model shown, the late Prof. Guthrie asked jokingly how much power it was expected that the motor would give. To which Mr. Baily modestly replied that at present he could only regard it as a scientific toy.
See also
Arago's Rotations
Timeline of the Electric Motor
Rotating magnetic Field
Induction Motor
References
External links
Proceedings of the Physical Society of London
Electric motors
18th-century inventions | Walter Baily's Motor | [
"Technology",
"Engineering"
] | 893 | [
"Electrical engineering",
"Engines",
"Electric motors"
] |
66,374,616 | https://en.wikipedia.org/wiki/Convergence%20space | In mathematics, a convergence space, also called a generalized convergence, is a set together with a relation called a that satisfies certain properties relating elements of X with the family of filters on X. Convergence spaces generalize the notions of convergence that are found in point-set topology, including metric convergence and uniform convergence. Every topological space gives rise to a canonical convergence but there are convergences, known as , that do not arise from any topological space. An example of convergence that is in general non-topological is almost everywhere convergence. Many topological properties have generalizations to convergence spaces.
Besides its ability to describe notions of convergence that topologies are unable to, the category of convergence spaces has an important categorical property that the category of topological spaces lacks.
The category of topological spaces is not an exponential category (or equivalently, it is not Cartesian closed) although it is contained in the exponential category of pseudotopological spaces, which is itself a subcategory of the (also exponential) category of convergence spaces.
Definition and notation
Preliminaries and notation
Denote the power set of a set by The or in of a family of subsets is defined as
and similarly the of is
If (respectively ) then is said to be (respectively ) in
For any families and declare that
if and only if for every there exists some such that
or equivalently, if then if and only if The relation defines a preorder on If which by definition means then is said to be and also and is said to be The relation is called . Two families and are called ( ) if and
A is a non-empty subset that is upward closed in closed under finite intersections, and does not have the empty set as an element (i.e. ). A is any family of sets that is equivalent (with respect to subordination) to filter or equivalently, it is any family of sets whose upward closure is a filter. A family is a prefilter, also called a , if and only if and for any there exists some such that
A is any non-empty family of sets with the finite intersection property; equivalently, it is any non-empty family that is contained as a subset of some filter (or prefilter), in which case the smallest (with respect to or ) filter containing is called () .
The set of all filters (respectively prefilters, filter subbases, ultrafilters) on will be denoted by (respectively ).
The or filter on at a point is the filter
Definition of (pre)convergence spaces
For any if then define
and if then define
so if then if and only if The set is called the of and is denoted by
A on a non-empty set is a binary relation with the following property:
: if then implies
In words, any limit point of is necessarily a limit point of any finer/subordinate family
and if in addition it also has the following property:
: if then
In words, for every the principal/discrete ultrafilter at converges to
then the preconvergence is called a on
A or a (respectively a ) is a pair consisting of a set together with a convergence (respectively preconvergence) on
A preconvergence can be canonically extended to a relation on also denoted by by defining
for all This extended preconvergence will be isotone on meaning that if then implies
Examples
Convergence induced by a topological space
Let be a topological space with If then is said to to a point in written in if where denotes the neighborhood filter of in The set of all such that in is denoted by or simply and elements of this set are called of in
The () or is the convergence on denoted by defined for all and all by:
if and only if in
Equivalently, it is defined by for all
A (pre)convergence that is induced by some topology on is called a ; otherwise, it is called a .
Power
Let and be topological spaces and let denote the set of continuous maps The is the coarsest topology on that makes the natural coupling into a continuous map
The problem of finding the power has no solution unless is locally compact. However, if searching for a convergence instead of a topology, then there always exists a convergence that solves this problem (even without local compactness). In other words, the category of topological spaces is not an exponential category (i.e. or equivalently, it is not Cartesian closed) although it is contained in the exponential category of pseudotopologies, which is itself a subcategory of the (also exponential) category of convergences.
Other named examples
Standard convergence on The is the convergence on defined for all and all by:
if and only if
Discrete convergence The on a non-empty set is defined for all and all by:
if and only if
A preconvergence on is a convergence if and only if
Empty convergence The on set non-empty is defined for all by:
Although it is a preconvergence on it is a convergence on The empty preconvergence on is a non-topological preconvergence because for every topology on the neighborhood filter at any given point necessarily converges to in
Chaotic convergence The on set non-empty is defined for all by: The chaotic preconvergence on is equal to the canonical convergence induced by when is endowed with the indiscrete topology.
Properties
A preconvergence on set non-empty is called or if is a singleton set for all It is called if for all and it is called if for all distinct
Every preconvergence on a finite set is Hausdorff. Every convergence on a finite set is discrete.
While the category of topological spaces is not exponential (i.e. Cartesian closed), it can be extended to an exponential category through the use of a subcategory of convergence spaces.
See also
Citations
References
Mathematical structures | Convergence space | [
"Physics",
"Mathematics"
] | 1,194 | [
"Mathematical structures",
"Mathematical objects",
"Topology",
"Space",
"Geometry",
"Spacetime"
] |
66,374,807 | https://en.wikipedia.org/wiki/Mary%20Jane%20Dockeray | Mary Jane Patricia Dockeray (March 8, 1927 – August 18, 2020) was an American environmental educator, founder of the Blandford Nature Center and Environmental Education Center in Grand Rapids, Michigan. In 2012, she was admitted to the Michigan Women's Hall of Fame.
Early life
Dockeray grew up on poultry farm in Walker Township. Her father, Winfield Dockeray, was a bookkeeper who also raised chickens. The family owned 2.5 acres just outside of Grand Rapids, an area where neighbors raised goats and open space was plentiful.
Dockeray attended Oakleigh School, a 7th Day Adventist Academy. Her 5th grade teacher, Anna Nelson, discovered that she had an interest in geology and the world around her. Nelson, who was typically quite austere, realized the interest in the young girl and helped Dockeray grow her love of geology.
Career
Dockeray was a curator of natural history at the Grand Rapids Public Museum in the 1950s and 1960s. She taught summer programs and visited schools to give science presentations. She began developing the Blandford Nature Center with an initial land donation in the 1960s, and the visitor center opened in 1968. She worked at the center until her retirement in 1990, but continued to volunteer at the center after that milestone. She taught at Michigan State University and at Aquinas College, hosted a radio program, Nature Spy, wrote a book, Let’s Go Exploring: Suggestions for Field Trips and Associated Studies in Environmental-Conservation Education, and narrated an educational film, These Things Are Ours (1963). Into her eighties, she was still giving geological tours of Grand Rapids.
Dockeray served on the executive board of the Michigan Audubon Society, and was recognized by the society with an Outstanding Member Award in 1985. She was inducted into the Michigan Women's Hall of Fame in 2012. The Blandford Nature Center's Mary Jane Dockeray Visitor Center opened in 2017. "If people can become better informed about the natural world around, they’ll take better care and their lives will be richer," she explained of her work.
In addition, Dockeray created and made the movie "These Things Are Ours," which was shown as part of National Audubon Society lecture tours across the US and Canada. Dockeray's school visits and lectures with her vintage slide projector were also memorable.
Personal life
Dockeray self-published a memoir, Rock On, Lady: Memoirs of Dr. Mary Jane Dockeray, Geologist Naturalist, in 2014. At a young age Dockeray made the decision to put her career before marriage, and she dedicated her life to her work. Later on in her life she became engaged to her longtime partner, fellow Blandford volunteer Bertrand L. Hewett, until his death on June 18, 2008. She died 12 years later on August 18, 2020. She was dedicated to the Blandford Centre right up until the day she died, and this dedication continued after her passing as she requested that people donate to the Mary Jane Dockeray Endowment Fund at the Blandford Nature Center on her behalf.
Legacy
Dockeray's legacy is the Blandford Nature Center she founded in 1968 and the Blandford Environmental Education Program The center, located in Grand Rapids, Michigan, began as Collins Woods which was a part of a family farm where Dockeray grew up and developed her love of the outdoors. Blandford Center preserves over 143 acres of land. Their mission as stated on their website is to engage, empower, and educate their community through enriching experiences in nature. The center hosts nature trails, an interpretive center, farm demonstrations, several historic buildings, and a wildlife care program. The Blandford Environmental Education Program allows children to experience a full year in nature, it connects every academic subject to nature.
Grand Valley State University offers a Scholarship (Mary Jane Dockeray Scholarship) honoring her legacy. The scholarship is awarded to students pursuing education in science.
Publications and projects
Book: Let's Go Exploring: Suggestions for Field Trip and Associated Studies in Environmental-Conservation Education
Film: These Things Are Ours
Memoir: Rock on, Lady: Memoirs of Dr. Mary Jane Dockeray, Geologist Naturalist
Radio Program: Nature Spy
Awards
Michigan Audubon Society Outstanding Member Award
Michigan Women's Hall of Fame
Inaugural Association of Nature Center Administrators’ President's Award for exemplary leadership in the Nature and Environmental Learning Center Profession
References
External links
Blandford Nature Center website
Mary Jane Dockeray profile at Michigan Women Forward
"Paving the Way for Nature" (2017), a half-hour interview with Dockeray; on YouTube
"Go on an Adventure with Mary Jane Dockeray" (2016), a video about Blandford Nature Center, featuring Dockeray; on YouTube
Howard Meyerson (October 4, 2013), "A Life of Conservation: Mary Jane Dockeray" The Outdoor Journal. A blogpost profiling Dockeray
Shelley Irwin (August 21, 2020), "Blandford Nature Center", a WGVU radio interview with Jason Meyer, on the occasion of Dockeray's death
1927 births
2020 deaths
American educators
American women geologists
Michigan State University alumni
Environmental education
People from Grand Rapids, Michigan
Michigan State University faculty
Aquinas College (Michigan) faculty | Mary Jane Dockeray | [
"Environmental_science"
] | 1,076 | [
"Environmental education",
"Environmental social science"
] |
66,374,918 | https://en.wikipedia.org/wiki/4-AcO-DPT | 4-Acetyloxy-N,N-dipropyltryptamine (or 4-AcO-DPT) is a tryptamine derivative. 4-AcO-DPT has been sold as a designer drug. It is an ester of 4-HO-DPT, a psychedelic tryptamine first synthesized by Alexander Shulgin. Anecdotal reports indicate that 4-AcO-DPT exerts psychoactive effects in humans, however, the pharmacology of 4-AcO-DPT has not been examined.
See also
4-AcO-DMT
4-HO-DPT
Dipropyltryptamine
References
Tryptamines
Designer drugs
Acetate esters | 4-AcO-DPT | [
"Chemistry"
] | 152 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
66,375,109 | https://en.wikipedia.org/wiki/Jeannette%20Janssen | Jeannette Catharina Maria Janssen is a Dutch and Canadian mathematician whose research concerns graph theory and the theory of complex networks. She is a professor of mathematics at Dalhousie University, the chair of the Dalhousie Department of Mathematics and Statistics, and the chair of the Activity Group on Discrete Mathematics of the Society for Industrial and Applied Mathematics.
Education and career
Janssen earned a master's degree at the Eindhoven University of Technology in 1988. She completed her Ph.D. at Lehigh University in 1993. Her dissertation, Even and Odd Latin Squares, concerned Latin squares and was supervised by Edward F. Assmus Jr.
From 1988 to 1990 Janssen was a lecturer at the Universidad de Guanajuato in Mexico. After completing her Ph.D., she became a postdoctoral researcher jointly at the Laboratoire de Combinatoire et d’Informatique Mathématique of Université du Québec à Montréal and at Concordia University. She took a position as a lecturer and research associate at the London School of Economics in 1995, and moved to Acadia University in 1997 before taking her present position at Dalhousie University.
At Dalhousie, she was named department chair in 2016, becoming the first female chair of the mathematics department.
Service
Janssen directed the Atlantic Association for Research in the Mathematical Sciences from 2011 to 2016, and chairs its board of directors. She was elected as chair of the Activity Group on Discrete Mathematics (SIAG-DM) of the Society for Industrial and Applied Mathematics (SIAM) for the 2021–2022 term.
Research
In a 1993 paper, Janssen solved the unbalanced case of the Dinitz conjecture, showing that any partial Latin rectangle could be extended to a full rectangle. The problem is equivalent to list edge-coloring of complete bipartite graphs, and her solution was based on earlier work on list coloring by Noga Alon and Michael Tarsi. Janssen's work "surprised even many of the experts", and was considered to be "great progress" on the Dinitz conjecture. The remaining case of the conjecture for squares (balanced complete bipartite graphs) was proven a year later by Fred Galvin.
References
External links
Home page
Year of birth missing (living people)
Living people
Canadian mathematicians
Canadian women mathematicians
Dutch mathematicians
Dutch women mathematicians
Graph theorists
Eindhoven University of Technology alumni
Lehigh University alumni
Academic staff of Universidad de Guanajuato
Academics of the London School of Economics
Academic staff of Acadia University
Academic staff of Dalhousie University | Jeannette Janssen | [
"Mathematics"
] | 517 | [
"Mathematical relations",
"Graph theory",
"Graph theorists"
] |
66,375,343 | https://en.wikipedia.org/wiki/Diiodoacetylene | Diiodoacetylene is the organoiodine compound with the formula C2I2. It is a white, volatile solid that dissolves in organic solvents. It is prepared by iodination of trimethylsilylacetylene. Although samples explode above 80 °C, diiodoacetylene is the most readily handled of the dihaloacetylenes. Dichloroacetylene, for example, is more volatile and more explosive. As confirmed by X-ray crystallography, diiodoacetylene is linear. It is however a shock, heat and friction sensitive compound. Like other haloalkynes, diiodoacetylene is a strong halogen bond donor.
References
Inorganic carbon compounds
Organoiodides
Dihaloacetylenes | Diiodoacetylene | [
"Chemistry"
] | 164 | [
"Inorganic carbon compounds",
"Inorganic compounds"
] |
61,379,828 | https://en.wikipedia.org/wiki/Berlekamp%E2%80%93Rabin%20algorithm | In number theory, Berlekamp's root finding algorithm, also called the Berlekamp–Rabin algorithm, is the probabilistic method of finding roots of polynomials over the field with elements. The method was discovered by Elwyn Berlekamp in 1970 as an auxiliary to the algorithm for polynomial factorization over finite fields. The algorithm was later modified by Rabin for arbitrary finite fields in 1979. The method was also independently discovered before Berlekamp by other researchers.
History
The method was proposed by Elwyn Berlekamp in his 1970 work on polynomial factorization over finite fields. His original work lacked a formal correctness proof and was later refined and modified for arbitrary finite fields by Michael Rabin. In 1986 René Peralta proposed a similar algorithm for finding square roots in . In 2000 Peralta's method was generalized for cubic equations.
Statement of problem
Let be an odd prime number. Consider the polynomial over the field of remainders modulo . The algorithm should find all in such that in .
Algorithm
Randomization
Let . Finding all roots of this polynomial is equivalent to finding its factorization into linear factors. To find such factorization it is sufficient to split the polynomial into any two non-trivial divisors and factorize them recursively. To do this, consider the polynomial where is some element of . If one can represent this polynomial as the product then in terms of the initial polynomial it means that , which provides needed factorization of .
Classification of elements
Due to Euler's criterion, for every monomial exactly one of following properties holds:
The monomial is equal to if ,
The monomial divides if is quadratic residue modulo ,
The monomial divides if is quadratic non-residual modulo .
Thus if is not divisible by , which may be checked separately, then is equal to the product of greatest common divisors and .
Berlekamp's method
The property above leads to the following algorithm:
Explicitly calculate coefficients of ,
Calculate remainders of modulo by squaring the current polynomial and taking remainder modulo ,
Using exponentiation by squaring and polynomials calculated on the previous steps calculate the remainder of modulo ,
If then mentioned below provide a non-trivial factorization of ,
Otherwise all roots of are either residues or non-residues simultaneously and one has to choose another .
If is divisible by some non-linear primitive polynomial over then when calculating with and one will obtain a non-trivial factorization of , thus algorithm allows to find all roots of arbitrary polynomials over .
Modular square root
Consider equation having elements and as its roots. Solution of this equation is equivalent to factorization of polynomial over . In this particular case problem it is sufficient to calculate only . For this polynomial exactly one of the following properties will hold:
GCD is equal to which means that and are both quadratic non-residues,
GCD is equal to which means that both numbers are quadratic residues,
GCD is equal to which means that exactly one of these numbers is quadratic residue.
In the third case GCD is equal to either or . It allows to write the solution as .
Example
Assume we need to solve the equation . For this we need to factorize . Consider some possible values of :
Let . Then , thus . Both numbers are quadratic non-residues, so we need to take some other .
Let . Then , thus . From this follows , so and .
A manual check shows that, indeed, and .
Correctness proof
The algorithm finds factorization of in all cases except for ones when all numbers are quadratic residues or non-residues simultaneously. According to theory of cyclotomy, the probability of such an event for the case when are all residues or non-residues simultaneously (that is, when would fail) may be estimated as where is the number of distinct values in . In this way even for the worst case of and , the probability of error may be estimated as and for modular square root case error probability is at most .
Complexity
Let a polynomial have degree . We derive the algorithm's complexity as follows:
Due to the binomial theorem , we may transition from to in time.
Polynomial multiplication and taking remainder of one polynomial modulo another one may be done in , thus calculation of is done in .
Binary exponentiation works in .
Taking the of two polynomials via Euclidean algorithm works in .
Thus the whole procedure may be done in . Using the fast Fourier transform and Half-GCD algorithm, the algorithm's complexity may be improved to . For the modular square root case, the degree is , thus the whole complexity of algorithm in such case is bounded by per iteration.
References
Algorithms
Algebra
Number theoretic algorithms
Polynomials | Berlekamp–Rabin algorithm | [
"Mathematics"
] | 964 | [
"Applied mathematics",
"Algorithms",
"Mathematical logic",
"Polynomials",
"Algebra"
] |
61,381,287 | https://en.wikipedia.org/wiki/Kamif%C5%ABsen | The term refers to several types of paper balloons in Japanese culture. They are simple toys for children, advertising give-aways for traditional medicine companies, and illuminated flying balloons at festivals.
Smaller kamifūsen are popular as traditional children's toys in Japan. These have an open hole, and reinflate as they are bounced in play. The balloon is made of glassine paper known as washi, which is air-resistant, glossy and thin, and which has sufficient plasticity to allow it to be formed into a new shape, which it can then retain. The properties of these paper balloon toys are of interest to scientists.
Traditionally, kamifūsen were sold in dagashiya, small shops selling candy, snacks and inexpensive toys to schoolchildren as an alternative to the more expensive rubber balloon. They are now sold in souvenir shops and online.
Another variation, known as the is in the shape of a cube rather than a sphere, and is associated with the marketing campaigns of traditional medicine companies. Much larger kamifūsen, resembling sky lanterns, are flown each year at the in Semboku, Akita.
Physics
Toy kamifūsen display some counterintuitive properties that have been studied by scientists. Even though they have an open hole, they tend to inflate rather than deflating when bounced up by a person's hands. According to Ichiro Fukumori of the Jet Propulsion Laboratory, "Despite the open hole visible in the silver patch, the kamifūsen stays inflated when bounced on the palm of one’s hand. Moreover, repeated bouncing causes a deflated kamifūsen to swell by itself to its fully inflated condition. The elastic rebound of the balloon paper is not enough to explain the full inflation; a batted kamifūsen actually sucks in air from the atmosphere."
Variations
Some kamifūsen intended for decoration are made in the shapes of animals, birds and fruits.
A kakufūsen (角風船) (kaku means "angled") is a paper balloon in the shape of a cube rather than a sphere, often used for commercial marketing purposes. Door-to-door salesmen called baiyaku-san (売薬さん) from the traditional medicine companies of Toyama used to give out kakūfūsen printed with drug company advertising. Small chests filled with various medicines and bandages were left at no initial cost with customers, and the salesman would return from time to time, to restock the cabinet and collect payment. This system of "use first, pay later" marketing of medicines is called "okigusuri".
The Kamihinokinai Paper Balloon Festival (上桧木内の紙風船上げ) is held in Semboku, Akita on February 10 each year. Hundreds of very large hot-air kamifūsen, resembling sky lanterns, are flown for good luck in the coming year. The festival has mythical origins, and was suspended during World War II. It was revived in 1974. According to tradition, Hiraka Gennai (1728-1780), a scientist in the Edo era, introduced paper balloons as markers for the copper mines in the mountains of the region, and also as entertainment.
In Japanese culture
Two major Japanese films have featured kamifūsen in their titles. Humanity and Paper Balloons (人情紙風船 Ninjō Kami Fūsen) is an acclaimed 1937 drama film, and Torasan and a Paper Balloon つらいよ 寅次郎紙風船 Otoko wa Tsurai yo: Torajirō Kamifūsen) is a 1981 comedy.
See also
Fu-Go balloon bomb
Paper lantern
Sky lantern
References
Further reading
External links
Base Camp Math: How to Inflate a Paper Kamifusen Balloon:Tadashi Tokieda, Professor of Mathematics at Stanford University, illustrates and explains how a toy paper ball can be inflated without being blown up. (video)
Balloons
Novelty items
Paper toys
Inflatable manufactured goods
Traditional toys | Kamifūsen | [
"Chemistry"
] | 820 | [
"Balloons",
"Fluid dynamics"
] |
61,382,917 | https://en.wikipedia.org/wiki/Polybotryoideae | Polybotryoideae is a subfamily of the fern family Dryopteridaceae.
Genera
The Pteridophyte Phylogeny Group classification of 2016 (PPG I) accepts the following genera:
Cyclodium C.Presl
Maxonia C.Chr
Olfersia Raddi
Polybotrya Humb. & Bonpl. ex Willd.
Polystichopsis (J.Sm.) C.Chr.
Stigmatocarpum L.Bolus
Stigmatopteris C.Chr.
Trichoneuron Ching
References
Dryopteridaceae
Plant subfamilies | Polybotryoideae | [
"Biology"
] | 129 | [
"Plant subfamilies",
"Plants"
] |
61,384,892 | https://en.wikipedia.org/wiki/Spectral%20imaging%20%28radiography%29 | Spectral imaging is an umbrella term for energy-resolved X-ray imaging in medicine. The technique makes use of the energy dependence of X-ray attenuation to either increase the contrast-to-noise ratio, or to provide quantitative image data and reduce image artefacts by so-called material decomposition. Dual-energy imaging, i.e. imaging at two energy levels, is a special case of spectral imaging and is still the most widely used terminology, but the terms "spectral imaging" and "spectral CT" have been coined to acknowledge the fact that photon-counting detectors have the potential for measurements at a larger number of energy levels.
Background
The first medical application of spectral imaging appeared in 1953 when B. Jacobson at the Karolinska University Hospital, inspired by X-ray absorption spectroscopy, presented a method called "dichromography" to measure the concentration of iodine in X-ray images. In the 70's, spectral computed tomography (CT) with exposures at two different voltage levels was proposed by G.N. Hounsfield in his landmark CT paper. The technology evolved rapidly during the 70's and 80's, but technical limitations, such as motion artifacts, for long held back widespread clinical use.
In recent years, however, two fields of technological breakthrough have spurred a renewed interest in energy-resolved imaging. Firstly, single-scan energy-resolved CT was introduced for routine clinical use in 2006 and is now available by several major manufacturers, which has resulted in a large and expanding number of clinical applications. Secondly, energy-resolving photon-counting detectors start to become available for clinical practice; the first commercial photon-counting system was introduced for mammography in 2003, and CT systems are at the verge of being feasible for routine clinical use.
Spectral image acquisition
An energy-resolved imaging system probes the object at two or more photon energy levels. In a generic imaging system, the projected signal in a detector element at energy level is
where is the number of incident photons, is the normalized incident energy spectrum, and is the detector response function. Linear attenuation coefficients and integrated thicknesses for materials that make up the object are denoted and (attenuation according to Lambert–Beers law). Two conceivable ways of acquiring spectral information are to either vary with , or to have -specific , here denoted incidence-based and detection-based methods, respectively.
Most elements appearing naturally in human bodies are of low atomic number and lack absorption edges in the diagnostic X-ray energy range. The two dominating X-ray interaction effects are then Compton scattering and the photo-electric effect, which can be assumed to be smooth and with separable and independent material and energy dependences. The linear attenuation coefficients can hence be expanded as
In contrast-enhanced imaging, high-atomic-number contrast agents with K absorption edges in the diagnostic energy range may be present in the body. K-edge energies are material specific, which means that the energy dependence of the photo-electric effect is no longer separable from the material properties, and an additional term can be added to Eq. () according to
where and are the material coefficient and energy dependency of contrast-agent material .
Energy weighting
Summing the energy bins in Eq. () () yields a conventional non-energy-resolved image, but because X-ray contrast varies with energy, a weighted sum () optimizes the contrast-to-noise-ratio (CNR) and enables a higher CNR at a constant patient dose or a lower dose at a constant CNR. The benefit of energy weighting is highest where the photo-electric effect dominates and lower in high-energy regions dominated by Compton scattering (with weaker energy dependence).
Energy weighting was pioneered by Tapiovaara and Wagner and has subsequently been refined for projection imaging and CT with CNR improvements ranging from a few percent up to tenth of percent for heavier elements and an ideal CT detector. An example with a realistic detector was presented by Berglund et al. who modified a photon-counting mammography system and raised the CNR of clinical images by 2.2–5.2%.
Material decomposition
Equation () can be treated as a system of equations with material thicknesses as unknowns, a technique broadly referred to as material decomposition. System properties and linear attenuation coefficients need to be known, either explicitly (by modelling) or implicitly (by calibration). In CT, implementing material decomposition post reconstruction (image-based decomposition) does not require coinciding projection data, but the decomposed images may suffer from beam-hardening artefacts because the reconstruction algorithm is generally non-reversible. Applying material decomposition directly in projection space instead (projection-based decomposition), can in principle eliminate beam-hardening artefacts because the decomposed projections are quantitative, but the technique requires coinciding projection data such as from a detection-based method.
In the absence of K-edge contrast agents and any other information about the object (e.g. thickness), the limited number of independent energy dependences according to Eq. () means that the system of equations can only be solved for two unknowns, and measurements at two energies () are necessary and sufficient for a unique solution of and . Materials 1 and 2 are referred to as basis materials and are assumed to make up the object; any other material present in the object will be represented by a linear combination of the two basis materials.
Material-decomposed images can be used to differentiate between healthy and malignant tissue, such as micro calcifications in the breast, ribs and pulmonary nodules, cysts, solid tumors and normal breast tissue, posttraumatic bone bruises (bone marrow edema) and the bone itself, different types of renal calculi (stones), and gout in the joints. The technique can also be used to characterize healthy tissue, such as the composition of breast tissue (an independent risk factor for breast cancer) and bone-mineral density (an independent risk factor for fractures and all-cause mortality). Finally, virtual autopsies with spectral imaging can facilitate detection and characterization of bullets, knife tips, glass or shell fragments etc.
The basis-material representation can be readily converted to images showing the amounts of photoelectric and Compton interactions by invoking Eq. (), and to images of effective-atomic-number and electron density distributions. As the basis-material representation is sufficient to describe the linear attenuation of the object, it is possible to calculate virtual monochromatic images, which is useful for optimizing the CNR to a certain imaging task, analogous to energy weighting. For instance, the CNR between grey and white brain matter is maximized at medium energies, whereas artefacts caused by photon starvation are minimized at higher virtual energies.
K-edge imaging
In contrast-enhanced imaging, additional unknowns may be added to the system of equations according to Eq. () if one or several K absorption edges are present in the imaged energy range, a technique often referred to as K-edge imaging. With one K-edge contrast agent, measurements at three energies () are necessary and sufficient for a unique solution, two contrast agents can be differentiated with four energy bins (), etc. K-edge imaging can be used to either enhance and quantify, or to suppress a contrast agent.
Enhancement of contrast agents can be used for improved detection and diagnosis of tumors, which exhibit increased retention of contrast agents. Further, differentiation between iodine and calcium is often challenging in conventional CT, but energy-resolved imaging can facilitate many procedures by, for instance, suppressing bone contrast and improving characterization of atherosclerotic plaque. Suppression of contrast agents is employed in so-called virtual unenhanced or virtual non-contrast (VNC) images. VNC images are free from iodine staining (contrast-agent residuals), can save dose to the patient by reducing the need for an additional non-contrast acquisition, can improve radiotherapy dose calculations from CT images, and can help in distinguishing between contrast agent and foreign objects.
Most studies of contrast-enhanced spectral imaging have used iodine, which is a well-established contrast agent, but the K edge of iodine at 33.2 keV is not optimal for all applications and some patients are hypersensitive to iodine. Other contrast agents have therefore been proposed, such as gadolinium (K edge at 50.2 keV), nanoparticle silver (K edge at 25.5 keV), zirconium (K edge at 18.0 keV), and gold (K edge at 80.7 keV). Some contrast agents can be targeted, which opens up possibilities for molecular imaging, and using several contrast agents with different K-edge energies in combination with photon-counting detectors with a corresponding number of energy thresholds enable multi-agent imaging.
Technologies and methods
Incidence-based methods obtain spectral information by acquiring several images at different tube voltage settings, possibly in combination with different filtering. Temporal differences between the exposures (e.g. patient motion, variation in contrast-agent concentration) for long limited practical implementations, but dual-source CT and subsequently rapid kV switching have now virtually eliminated the time between exposures. Splitting the incident radiation of a scanning system into two beams with different filtration is another way to quasi-simultaneously acquire data at two energy levels.
Detection-based methods instead obtain spectral information by splitting the spectrum after interaction in the object. So-called sandwich detectors consist of two (or more) detector layers, where the top layer preferentially detects low-energy photons and the bottom layer detects a harder spectrum. Detection-based methods enable projection-based material decomposition because the two energy levels measured by the detector represent identical ray paths. Further, spectral information is available from every scan, which has work-flow advantages.
The currently most advanced detection-based method is based on photon-counting detectors. As opposed to conventional detectors, which integrate all photon interactions over the exposure time, photon-counting detectors are fast enough to register and measure the energy of single photon events. Hence, the number of energy bins and the spectral separation are not determined by physical properties of the system (detector layers, source / filtration etc.), but by the detector electronics, which increases efficiency and the degrees of freedom, and enable elimination of electronic noise. The first commercial photon-counting application was the MicroDose mammography system, introduced by Sectra Mamea in 2003 (later acquired by Philips), and spectral imaging was launched on this platform in 2013.
The MicroDose system was based on silicon strip detectors, a technology that has subsequently been refined for CT with up to eight energy bins. Silicon as sensor material benefit from high charge-collection efficiency, ready availability of high-quality high-purity silicon crystals, and established methods for test and assembly. The relatively low photo-electric cross section can be compensated for by arranging the silicon wafers edge on, which also enables depth segments. Cadmium telluride (CdTe) and cadmium–zinc telluride (CZT) are also being investigated as sensor materials. The higher atomic number of these materials result in a higher photo-electric cross section, which is advantageous, but the higher fluorescent yield degrades spectral response and induces cross talk. Manufacturing of macro-sized crystals of these materials have so far posed practical challenges and leads to charge trapping and long-term polarization effects (build-up of space charge). Other solid-state materials, such as gallium arsenide and mercuric iodide, as well as gas detectors, are currently quite far from clinical implementation.
The main intrinsic challenge of photon-counting detectors for medical imaging is pulse pileup, which results in lost counts and reduced energy resolution because several pulses are counted as one. Pileup will always be present in photon-counting detectors because of the Poisson distribution of incident photons, but detector speeds are now so high that acceptable pileup levels at CT count rates begin to come within reach.
See also
Photon-counting mammography
Photon-counting computed tomography
References
Radiography
Medical imaging
Medical technology
X-ray computed tomography
Projectional radiography
Photonics | Spectral imaging (radiography) | [
"Biology"
] | 2,529 | [
"Medical technology"
] |
61,385,234 | https://en.wikipedia.org/wiki/Gene-environment%20interplay | Gene-environment interplay describes how genes and environments work together to produce a phenotype, or observable trait. Many human traits are influenced by gene-environment interplay. It is a key component in understanding how genes and the environment come together to impact human development. Examples of gene-environment interplay include gene-environment interaction and gene-environment correlation. Another type of gene-environment interplay is epigenetics, which is the study of how environmental factors can affect gene expression without altering DNA sequences.
To study the effect of the environment on the expression of the human genome, family-based behavioral genetic research methods such as twin, family and adoption studies are used. Moreover, the identification of genes under environmental influence can be completed through genome-wide association studies. Research on cases of gene-environment interplay allow for a deeper understanding of the nuances surrounding nature versus nurture debates. Environmental factors can cause deviations from expected gene expression, which ultimately impact cellular processes, such as cell signaling. They can also affect the likelihood of disease. By identifying environmental effects on cellular processes, scientists can gain a better understanding of the mechanisms behind diseases and gain insights into treating them.
Types
Gene-environment interactions (GxE)
Gene–environment interaction occurs when genetic factors and environmental factors interact to produce an outcome that cannot be explained by either factor alone. For example, a study found that individuals carrying the genetic variant 5-HTT (the short copy) that encodes the serotonin transporter were at a higher risk of developing depression when exposed to adverse childhood experiences, whereas those with other genotypes (long copy) were less affected by childhood maltreatment. However, there is a caveat as these stressful events may also be caused by an individual's predisposition for getting into these situations.
Gene-environment correlation (rGE)
Gene–environment correlations describe how different environmental exposures are statistically linked to genes. These correlations can emerge through multiple different mechanisms, both causal and non-causal. In regard to causal mechanisms, there are three common types of gene-environment correlations:
Passive
The childhood environment of an individual may be correlated with their inherited genes, since an individual's parents may have selected for their childhood environment. This type of correlation is considered "passive" since the child's environment is being determined by parental decisions rather than by the child's own decisions. For example, parents who have high openness-to-experience, which is a moderately heritable personality trait, are more likely to provide their children with musical training. Consequently, a correlation has also been documented between children with more openness-to-experience and their likelihood of receiving musical training as young children.
Evocative
This type of gene-environment correlation can emerge when an individual's genetics causes others to alter their environment. For instance, one study on children in middle childhood found that a child's innate desire for autonomy partially determined the degree of maternal control evoked.
Active
This occurs when individuals seek out environments that are compatible with their genetic predispositions. For example, a person with a genetic predisposition for athleticism may be more inclined to choose sports-related activities and environments.
Epigenetics
Epigenetics focuses on cellular changes in gene expression that do not involve changes in genetic code. Epigenetic changes can be a result of cellular mechanisms or environmental factors. One instance of an environment impacting gene expression is DNA methylation as a result of smoking during pregnancy. Another environmental exposure that can trigger epigenetic changes is heavy metals like arsenic. This is done through the disturbance of histone acetylation and DNA methylation which is correlated with increased rates of cancer, autoimmune diseases, and neurological disorders.
Environmental factors
Pollutants
Epigenetic modifications can affect gene activity independently of DNA sequence modifications. Air pollution exposure has been associated with decreased DNA methylation levels which is a process crucial for gene regulation. The effects of air pollution can be seen in the prenatal environment as methylation changed in response to the presence of NO2 and NOx,which are forms of air pollution. When exposed to air pollution, there was a decline in intrauterine growth. While the mechanism is not fully understood, it could involve the formation of reactive oxygen species, leading to oxidative stress and cellular signaling cascade or increased fetal cortisol levels. A consequence of altered DNA methylation is hydroxymethylation, which replaces the methyl group with a hydroxyl group. Hydroxymethylation potentially could disrupt gene expression patterns and contribute to disease development, such as lung cancer. Additionally, exposure to pollutants can exacerbate inflammatory conditions like asthma by inducing inflammation in the airways. This leads to increased cytokine expression and immune cell recruitment. Certain pollutants, such as endocrine-disrupting chemicals (EDC), interfere with hormone signaling pathways and gene expression related to hormone regulation. A certain type of EDC, bisphenol A has been linked to changes in gene expression in reproductive tissues and developmental pathways.
Malnutrition
Nutrition plays a crucial role in shaping gene expression, which can ultimately impact an individual's phenotype. Fetal malnutrition, for example, has been associated with decreased level DNA methylation, particularly on genes like IGF2, which is involved in insulin metabolism. The alteration in DNA methylation patterns can elevate the risk of developing metabolic disorders and type II diabetes mellitus. Furthermore, prenatal malnutrition can lead to differential DNA methylation of genes related to growth, development, and metabolism. These epigenetic changes increase the likelihood of adverse phenotypes such as obesity and high cholesterol later in life. Malnutrition can also significantly impact gene expression in the small intestine, leading to alterations in nutrient transporters, digestive enzymes, barrier function, immune responses, and metabolic adaptation. Socioeconomic factors such as poverty and minority status may exacerbate the effects of malnutrition. Research indicates that individuals that reside in impoverished communities or those who belong to marginalized racial and ethnic groups may encounter limited access to nutritious food options.
Exercise
Physical activity induces epigenetic modifications of specific genes, altering their expression profiles. For example, exercise has been linked to increased methylation of the ASC gene, which typically decreases with age. Methylation can compact a gene, decreasing the amount of protein produced from the gene and the ASC gene stimulates cytokine production. Thus, the expression of inflammatory cytokines decreases. This suppression can help prevent the development of chronic inflammation and associated age-related diseases due to excess inflammatory cytokines. However, these epigenetic modifications depend on the intensity and type of exercise and are reversible with the cessation of physical activity. Research shows that exercise for more than six months can have an effect on telomere length. Elongation at the ends of chromosomes helps to maintain chromosomal stability and induces epigenetic modifications of specific genes.
Prenatal environment
The maternal environment can have epigenetic effects on the developing fetus. For instance, alcohol consumed during pregnancy can cross from maternal blood to the placenta and into the fetal environment of the amniotic cavity, where it can induce epigenetic modifications on fetal DNA. Mouse embryo cultures show that alcohol exposure during fetal development can contribute to changes in DNA methylation of genes involved in development, metabolism, and organization of DNA during brain development. These alcohol-induced changes in DNA methylation during pregnancy contribute to the distinct set of traits seen in Fetal Alcohol Spectrum Disorder (FASD). Other instances of prenatal environment impact on fetal epigenetic state include maternal folic acid, stress, and tobacco smoking during pregnancy.
Early life stress
Early life stress encompasses parental absence, abuse, and lack of bonding. These stressors during early childhood are associated with epigenetic modifications of the Hypothalamic-Pituitary-Adrenal (HPA) axis, which mediates the stress response. Using a rat model of maternal care, research has shown that reduced care between mother and offspring is associated with down regulation of glucocorticoid receptors (GR) in the hypothalamus. GRs play a critical role in the HPA axis by aiding in the restoration of normal physiological state after stress exposure. Down regulation of GRs expression occurs through histone modifications and DNA methylation of the GR gene, resulting in dysregulation of the stress response, including prolonged inflammation and cellular damage. Additionally, numerous studies have linked early life stress with later-life psychiatric disorders, including anxiety and depression, through epigenetic modulation of genes involved in the HPA axis. Socioeconomic disparities, discrimination, and cultural factors prevalent within minority communities can contribute to heightened levels of stress and adversity, impacting gene expression and health outcomes.
Studies
Adoption and twin studies
Adoption and twin studies are used to investigate the complex interplay between genes and the environment. These studies typically involve the comparison of identical (monozygotic) and fraternal (dizygotic) twins to determine the extent to which genetic factors and environmental influences contribute to variations in traits or behaviors. These studies have contributed to studies of behavior, personality, and psychiatric illnesses. For example, a Finnish adoption study on schizophrenia revealed that a healthy environment can mitigate the effects of genetics in adopted individuals born to schizophrenic mothers. Criminal and antisocial behavior have also been found to be influenced by both genetic and environmental factors through these types of studies.
Animal models
Animal models provide a controlled and manipulable environment in which researchers can investigate the complex interactions between genes and environmental factors, shedding light on various biological and behavioral outcomes. For example, one study has demonstrated the utility of mouse models in understanding gene-environment interactions in schizophrenia due to the genetic similarities.
Research on moths and butterflies has shown that environmental factors like bright sunlight influences their color vision. In environments with more light, they develop more of different opsins which allow them to detect light and discern colors. Butterflies depend on color vision to find the correct flowers for their diet and their preferred habitat.
Medical Conditions
Gene-environment interplay has been found to play a part in the majority of diseases. For instance, gene-environment interactions have a prevalent role in mental health disorders; specifically, evidence has found a link to alcohol dependence, schizophrenia, and psychosis. The link to alcohol dependence is potentially influenced by a dopamine receptor gene (DRD2) as individuals with the TaqI allele may have interactions involving this allele and alcohol dependence. This interaction is more prevalent when the individual is experiencing higher stress levels. The impacts on psychosis originate from a single nucleotide polymorphism (SNP), in the AKT1 gene. This causes its carriers who regularly use cannabis to be more susceptible to developing psychosis. Additionally, individuals who are homozygous for this particular AKT1 mutation and use cannabis daily are at an increased risk for developing psychotic disorders. For schizophrenia, genome-wide by environment interaction studies (GWEIS) and genome-wide association studies (GWAS) are used to determine the loci at environmental factors used in the determination of GxE. Evidence also supports that gene-environment interplay is connected to cardiovascular and metabolic conditions. These include roles in obesity, pulmonary disease, and diabetes. The rise in the incidence of type II diabetes is suggested to be linked to interactions between diet and the FTO and KCNQ1 genes. Mutations within the KCNQ1 gene affects a pathway that leads to a decrease in insulin secretion due to a decline in pancreatic β cells, but within mice fed a high fat diet enhanced the dysfunction within the pancreatic β cells.
References
Genetics terms | Gene-environment interplay | [
"Biology"
] | 2,430 | [
"Genetics terms"
] |
61,385,952 | https://en.wikipedia.org/wiki/Infundibulicybe%20gibba | Infundibulicybe gibba (also known as Clitocybe gibba), and commonly known as the common funnel or funnel cap, is a species of gilled mushroom which is common in European woods.
Naming
The epithet gibba comes from the Latin adjective "gibbus", meaning "humped" or "gibbous".
This species was originally described by the mycologist Christiaan Hendrik Persoon in 1801 as Agaricus gibbus, at a time when gilled mushrooms were generally all assigned to genus Agaricus. Then in 1871 in his guide to mycology ("Der Führer in die Pilzkunde"), Paul Kummer allocated the species to the genus Clitocybe, which previously (according to the system of Fries) had only been a tribe within genus Agaricus.
In 2003 Harri Harmaja created the new genus Infundibulicybe for some of the larger members of the former Clitocybe and he included Infundibulicybe gibba as the type species.
Clitocybe catinus
Clitocybe catinus is described as differing from C. gibba by having white cap with occasionally some pink tonality and its slight smell of flour.
Harmaja (2003) gave it a new name Infundibulicybe catinus.
Vizzini et al. (2011) listed it a color variant of Infundibulicybe gibba.
Clitocybe infundibuliformis
The older name Clitocybe infundibuliformis is often identified as a synonym of I. gibba, but according to Species Fungorum that use was incorrect and the original C. infundibuliformis was a different mushroom.
The name infundibuliformis derives from the Latin "infundibulum", a funnel, with the suffix "-formis" - so it means "funnel-shaped".
Description
This section uses the given references throughout.
The matt slightly felted cap grows from about 3 cm to 9 cm, and is beige to tan, also sometimes with a pink tinge. It soon becomes funnel-shaped but often has a small bulge (an "umbo") in the centre.
There is no ring or other veil remnant. The stem is white or whitish and about 2–8 cm long and 1 cm in diameter.
The white gills are crowded and very decurrent (running down the stem).
It has a faint "cyanic" smell, like new-mown hay, and the taste is mild. However, there is also a central European variety "adstringens" which has an unpleasant taste.
The tear-shaped spores are white and around 5.5–8 μm by 4–5 μm.
Distribution, habitat, ecology and human impact
This gregarious saprobic mushroom grows on soil in deciduous or (less commonly) coniferous woods and may be found from summer to autumn. It sometimes forms fairy rings.
It is very common throughout Europe, and occurs in North America and Japan.
It is edible when young, but said to be of mediocre quality. It can be fried or used in risottos or soups etc. The stems are tough and may be discarded. The species resembles some which are poisonous.
An extract of I. gibba exhibits inhibitory activity on thrombin.
Similar species
The species resembles Infundibulicybe squamulosa and Pseudoclitocybe cyathiformis.
References
Agaricales
Edible fungi
Fungi described in 1801
Fungi of Europe
Taxa named by Christiaan Hendrik Persoon
Fungus species | Infundibulicybe gibba | [
"Biology"
] | 766 | [
"Fungi",
"Fungus species"
] |
61,387,167 | https://en.wikipedia.org/wiki/Ind-completion | In mathematics, the ind-completion or ind-construction is the process of freely adding filtered colimits to a given category C. The objects in this ind-completed category, denoted Ind(C), are known as direct systems, they are functors from a small filtered category I to C.
The dual concept is the pro-completion, Pro(C).
Definitions
Filtered categories
Direct systems depend on the notion of filtered categories. For example, the category N, whose objects are natural numbers, and with exactly one morphism from n to m whenever , is a filtered category.
Direct systems
A direct system or an ind-object in a category C is defined to be a functor
from a small filtered category I to C. For example, if I is the category N mentioned above, this datum is equivalent to a sequence
of objects in C together with morphisms as displayed.
The ind-completion
Ind-objects in C form a category ind-C.
Two ind-objects
and
determine a functor
Iop x J Sets,
namely the functor
The set of morphisms between F and G in Ind(C) is defined to be the colimit of this functor in the second variable, followed by the limit in the first variable:
More colloquially, this means that a morphism consists of a collection of maps for each i, where is (depending on i) large enough.
Relation between C and Ind(C)
The final category I = {*} consisting of a single object * and only its identity morphism is an example of a filtered category. In particular, any object X in C gives rise to a functor
and therefore to a functor
This functor is, as a direct consequence of the definitions, fully faithful. Therefore Ind(C) can be regarded as a larger category than C.
Conversely, there need not in general be a natural functor
However, if C possesses all filtered colimits (also known as direct limits), then sending an ind-object (for some filtered category I) to its colimit
does give such a functor, which however is not in general an equivalence. Thus, even if C already has all filtered colimits, Ind(C) is a strictly larger category than C.
Objects in Ind(C) can be thought of as formal direct limits, so that some authors also denote such objects by
This notation is due to Pierre Deligne.
Universal property of the ind-completion
The passage from a category C to Ind(C) amounts to freely adding filtered colimits to the category. This is why the construction is also referred to as the ind-completion of C. This is made precise by the following assertion: any functor taking values in a category D that has all filtered colimits extends to a functor that is uniquely determined by the requirements that its value on C is the original functor F and such that it preserves all filtered colimits.
Basic properties of ind-categories
Compact objects
Essentially by design of the morphisms in Ind(C), any object X of C is compact when regarded as an object of Ind(C), i.e., the corepresentable functor
preserves filtered colimits. This holds true no matter what C or the object X is, in contrast to the fact that X need not be compact in C. Conversely, any compact object in Ind(C) arises as the image of an object in X.
A category C is called compactly generated, if it is equivalent to for some small category . The ind-completion of the category FinSet of finite sets is the category of all sets. Similarly, if C is the category of finitely generated groups, ind-C is equivalent to the category of all groups.
Recognizing ind-completions
These identifications rely on the following facts: as was mentioned above, any functor taking values in a category D that has all filtered colimits, has an extension
that preserves filtered colimits. This extension is unique up to equivalence. First, this functor is essentially surjective if any object in D can be expressed as a filtered colimits of objects of the form for appropriate objects c in C. Second, is fully faithful if and only if the original functor F is fully faithful and if F sends arbitrary objects in C to compact objects in D.
Applying these facts to, say, the inclusion functor
the equivalence
expresses the fact that any set is the filtered colimit of finite sets (for example, any set is the union of its finite subsets, which is a filtered system) and moreover, that any finite set is compact when regarded as an object of Set.
The pro-completion
Like other categorical notions and constructions, the ind-completion admits a dual known as the pro-completion: the category Pro(C) is defined in terms of ind-object as
(The definition of pro-C is due to .)
Therefore, the objects of Pro(C) are or in C. By definition, these are direct system in the opposite category or, equivalently, functors
from a small category I.
Examples of pro-categories
While Pro(C) exists for any category C, several special cases are noteworthy because of connections to other mathematical notions.
If C is the category of finite groups, then pro-C is equivalent to the category of profinite groups and continuous homomorphisms between them.
The process of endowing a preordered set with its Alexandrov topology yields an equivalence of the pro-category of the category of finite preordered sets, , with the category of spectral topological spaces and quasi-compact morphisms.
Stone duality asserts that the pro-category of the category of finite sets is equivalent to the category of Stone spaces.
The appearance of topological notions in these pro-categories can be traced to the equivalence, which is itself a special case of Stone duality,
which sends a finite set to the power set (regarded as a finite Boolean algebra).
The duality between pro- and ind-objects and known description of ind-completions also give rise to descriptions of certain opposite categories. For example, such considerations can be used to show that the opposite category of the category of vector spaces (over a fixed field) is equivalent to the category of linearly compact vector spaces and continuous linear maps between them.
Applications
Pro-completions are less prominent than ind-completions, but applications include shape theory. Pro-objects also arise via their connection to pro-representable functors, for example in Grothendieck's Galois theory, and also in Schlessinger's criterion in deformation theory.
Related notions
Tate objects are a mixture of ind- and pro-objects.
Infinity-categorical variants
The ind-completion (and, dually, the pro-completion) has been extended to ∞-categories by .
See also
completions in category theory
Notes
References
.
Functors
Limits (category theory) | Ind-completion | [
"Mathematics"
] | 1,427 | [
"Functions and mappings",
"Mathematical structures",
"Mathematical objects",
"Mathematical relations",
"Functors",
"Category theory",
"Limits (category theory)"
] |
61,387,269 | https://en.wikipedia.org/wiki/Alison%20Todd | Alison Todd is an Australian scientist who is holder of 18 patents (as at July 2019), and a co-founder and chief scientific officer of SpeeDx. The company manufactures and sells tests for detecting infectious pathogens and identifying antibiotic resistance. The biomedical company, co-founded by Todd, develops diagnostic tools. Todd mentors younger scientists and entrepreneurs, as well as advocating for greater gender diversity in leaders in STEM.
Career
Todd is the Chief Scientific Officer of SpeeDx, which is a molecular diagnostics company which she and Elisa Mokany started. Todd and Mokany have 18 patent families between them. They have brought 11 medical diagnostic tests for the management of clinical disease.
Todd developed several novel molecular analytical technologies which have been used for basic research, preclinical/clinical drug development and in vitro diagnostics. Her expertise include nucleic acid chemistry, particularly target amplification and catalytic DNA technologies, and the biology of cancer and viral diseases. Prior to founding SpeeDx, Todd was a Senior Research Director at Johnson and Johnson Research Pty Limited, Sydney.
Research
Todd describes her "Eureka moment", "It all began when Elisa joined my group at Johnson & Johnson Research (JJR), we were already exploring ways to exploit DNAzymes (deoxyribozymes) for diagnostic applications. These fascinating molecules are simple, short, synthetic DNA sequences (oligonucleotides) that can catalyse reactions in a manner analogous to protein enzymes. Although catalytic RNA (ribozymes) had been found in nature, catalytic DNA had not, and it had been assumed DNA would not have similar properties. However, a few years earlier, undeterred by dogma, Jerry Joyce and co-workers at Scripps had conducted ‘evolution in a test tube’".
Select publications
Santoro, S., and Joyce, G. (1997) A general purpose RNA-cleaving SNA enzyne. Proc. Natl. Acad. Sci. USA 94, 4262-4266.
Todd, A.V., et al. (2000) DzyNA-PCR: use of DNAzymes to detect and quantify nucleic acid sequences in a real-time fluorescent format Clin. Chem. 46, 625-630.
Mokany, E., et al. (2010) MNAzymes, a Versatile New Class of Nucleic Acid Enzymes That Can Function as Biosensors and Molecular Switches J. Am. Chem. Soc. 132, 1051-1059.
Mokany, E., et al. (2013) MNAzyme qPCR with Superior Multiplexing Capacity Clin. Chem. 59, 419-426.
Todd's publications can be found at (Google Scholar).
Awards and recognition
Johnson & Johnson Philip B. Hofmann Research Scientist Award,
Todd was selected as one of the six Boss True Leaders Game Changers due to her research fighting superbugs.
Fellow of the Australian Academy of Technological Sciences and Engineering (FTSE)
Media
2017 — Todd's work was referenced in The Australian Financial Review, where she was described as a 'frontline fighter in the war on superbugs'.
2017 — The Sydney Morning Herald described the formation of Todd's company, as well as their concern that women were under-represented in STEMM, and the hiring and mentoring practices reflected in their company.
References
Australian women scientists
Living people
Women biochemists
Australian biochemists
Women inventors
Year of birth missing (living people)
Fellows of the Australian Academy of Technological Sciences and Engineering
21st-century Australian inventors
University of Sydney alumni | Alison Todd | [
"Chemistry"
] | 752 | [
"Biochemists",
"Women biochemists"
] |
61,387,397 | https://en.wikipedia.org/wiki/Codensity%20monad | In mathematics, especially in category theory, the codensity monad is a fundamental construction associating a monad to a wide class of functors.
Definition
The codensity monad of a functor is defined to be the right Kan extension of along itself, provided that this Kan extension exists. Thus, by definition it is in particular a functor
The monad structure on stems from the universal property of the right Kan extension.
The codensity monad exists whenever is a small category (has only a set, as opposed to a proper class, of morphisms) and possesses all (small, i.e., set-indexed) limits. It also exists whenever has a left adjoint.
By the general formula computing right Kan extensions in terms of ends, the codensity monad is given by the following formula:
where denotes the set of morphisms in between the indicated objects and the integral denotes the end. The codensity monad therefore amounts to considering maps from to an object in the image of and maps from the set of such morphisms to compatible for all the possible Thus, as is noted by Avery, codensity monads share some kinship with the concept of integration and double dualization.
Examples
Codensity monads of right adjoints
If the functor admits a left adjoint the codensity monad is given by the composite together with the standard unit and multiplication maps.
Concrete examples for functors not admitting a left adjoint
In several interesting cases, the functor is an inclusion of a full subcategory not admitting a left adjoint. For example, the codensity monad of the inclusion of FinSet into Set is the ultrafilter monad associating to any set the set of ultrafilters on This was proven by Kennison and Gildenhuys, though without using the term "codensity". In this formulation, the statement is reviewed by Leinster.
A related example is discussed by Leinster: the codensity monad of the inclusion of finite-dimensional vector spaces (over a fixed field ) into all vector spaces is the double dualization monad given by sending a vector space to its double dual
Thus, in this example, the end formula mentioned above simplifies to considering (in the notation above) only one object namely a one-dimensional vector space, as opposed to considering all objects in Adámek and Sousa show that, in a number of situations, the codensity monad of the inclusion
of finitely presented objects (also known as compact objects) is a double dualization monad with respect to a sufficiently nice cogenerating object. This recovers both the inclusion of finite sets in sets (where a cogenerator is the set of two elements), and also the inclusion of finite-dimensional vector spaces in vector spaces (where the cogenerator is the ground field).
Sipoş showed that the algebras over the codensity monad of the inclusion of finite sets (regarded as discrete topological spaces) into topological spaces are equivalent to Stone spaces.
Avery shows that the Giry monad arises as the codensity monad of natural forgetful functors between certain categories of convex vector spaces to measurable spaces.
Relation to Isbell duality
Di Liberti shows that the codensity monad is closely related to Isbell duality: for a given small category Isbell duality refers to the adjunction
between the category of presheaves on (that is, functors from the opposite category of to sets) and the opposite category of copresheaves on The monad
induced by this adjunction is shown to be the codensity monad of the Yoneda embedding
Conversely, the codensity monad of a full small dense subcategory in a cocomplete category is shown to be induced by Isbell duality.
See also
References
Footnotes
Further reading
Codensity Monads at the n-category café.
Category theory | Codensity monad | [
"Mathematics"
] | 829 | [
"Functions and mappings",
"Mathematical structures",
"Mathematical objects",
"Fields of abstract algebra",
"Mathematical relations",
"Category theory"
] |
61,387,587 | https://en.wikipedia.org/wiki/Oxygen%20effect | In biochemistry, the oxygen effect refers to a tendency for increased radiosensitivity of free living cells and organisms in the presence of oxygen than in anoxic or hypoxic conditions, where the oxygen tension is less than 1% of atmospheric pressure (i.e., <1% of 101.3 kPa, 760 mmHg or 760 torr).
Physiology and causes
Explanation of the oxygen effect and relevance to hypoxic tissues
The oxygen effect has particular importance in external beam radiation therapy where the killing of tumour cells with photon and electron beams in well oxygenated regions can be up to three times greater than in a poorly vasculated portion of the tumour.
Besides tumour hypoxia, the oxygen effect is also relevant to hypoxia conditions present in the normal physiology of stem cell niches such as the endosteum adjacent to bone in bone marrow and the epithelium layer of the intestine. In addition, there are non-malignant diseases where oxygenated tissues can become hypoxic such as in stenosed coronary arteries associated with cardiovascular disease.
Historical research on the oxygen effect
Holthusen (1921) first quantified the oxygen effect finding 2.5 to 3.0-fold less hatching eggs of the nematode Ascaris in oxygenated compared to anoxic conditions, which was incorrectly assigned to changes in cell division. However, two years later, Petry (1923) first attributed oxygen tension as affecting ionizing radiation effects on vegetable seeds. Later, the implications of the effects of oxygen on radiotherapy were discussed by Mottram (1936).
A key observation limiting hypotheses to explain the biological mechanisms of the oxygen effect is that the gas nitric oxide is a radiosensitizer with similar effects to oxygen observed in tumour cells. Another important observation is that oxygen must be present at irradiation or within milliseconds afterward for the oxygen effect to take place.
The best known explanation of the oxygen effect is the oxygen fixation hypothesis developed by Alexander in 1962, which posited that radiation-induced non-restorable or "fixed" nuclear DNA lesions are lethal to cells in the presence of diatomic oxygen. Recent hypotheses include one based on oxygen-enhanced damage from first principles. Another hypothesis posits that ionizing radiation provokes mitochondria to produce reactive oxygen (and nitrogen species), which are leakage during oxidative phosphorylation that varies with a hyperbolic saturation relationship observed with both the oxygen and nitric oxide effects.
Oxygen Enhancement Ratio and the effect of radiation LET
The oxygen effect is quantified by measuring the radiation sensitivity or Oxygen Enhancement Ratio (OER) of a particular biological effect (e.g., cell death or DNA damage), which is the ratio of doses under pure oxygen and anoxic conditions. Consequently, OER varies from unity in anoxia to a maximum value for 100% oxygen of typically up to three for low ionizing-density-radiation (beta-, gamma-, or x-rays), or so-called low linear energy transfer (LET) radiations.
Radiosensitivity varies most rapidly for oxygen partial pressures below ~1% atmospheric (Fig. 1). Howard-Flanders and Alper (1957) developed a formula for the hyperbolic function of OER and its variation with oxygen concentration, or oxygen pressure in air.
Radiobiologists identified additional characteristics of the oxygen effect that influence radiotherapy practices. They found that the maximum OER value diminishes as the ionizing-density of the radiation increases (Fig. 2), from low-LET to high-LET radiations. The OER is unity irrespective of the oxygen tension for alpha-particles of high-LET around 200 keV/μm. The OER is reduced for low doses as evaluated for cultured mammalian cells exposed to x-rays under aerobic (21% O2, 159 mmHg) and anoxic (nitrogen) conditions. Typical fractionation treatments are daily 2 Gy exposures, as below this dose the so-called 'shoulder' or repair region of the cell survival curve is encroached upon reducing the OER (Fig. 3).
References
Biochemistry
Ionizing radiation#Health effects
Medical physics
Oxygen
Radiation therapy
Radiobiology | Oxygen effect | [
"Physics",
"Chemistry",
"Biology"
] | 900 | [
"Ionizing radiation",
"Physical phenomena",
"Applied and interdisciplinary physics",
"Radiobiology",
"Radiation",
"Medical physics",
"nan",
"Biochemistry",
"Radioactivity"
] |
61,387,883 | https://en.wikipedia.org/wiki/List%20of%20amphibian%20genera | List of amphibian genera lists the vertebrate class of amphibians by genus, spanning two superorders.
Superorder Batrachia
Order Anura
Frogs
Suborder Archaeobatrachia
Family Alytidae - sometimes called Discoglossidae
Genus Alytes - Midwife toad
Genus Discoglossus
Genus Latonia
Family Ascaphidae
Genus Ascaphus - Tailed frog
Family Bombinatoridae
Genus Barbourula
Genus Bombina - Fire-bellied toad
Family Leiopelmatidae
Genus Leiopelma
Suborder Mesobatrachia
Family Megophryidae
Genus Borneophrys
Genus Brachytarsophrys - Karin Hills frog
Genus Leptobrachella
Genus Leptobrachium - Eastern spadefoot toad
Genus Leptolalax
Genus Megophrys
Genus Ophryophryne
Genus Oreolalax
Genus Scutiger
Family Pelobatidae
Genus Pelobates - European spadefoot toad
Family Pelodytidae
Genus Pelodytes - Parsley frog
Family Pipidae
Genus Hymenochirus - African dwarf frog
Genus Pipa
Genus Pseudhymenochirus - Merlin's dwarf gray frog
Genus Xenopus
Family Rhinophrynidae
Genus Rhinophrynus
Family Scaphiopodidae - American spadefoot toad
Genus Scaphiopus
Genus Spea
Suborder Neobatrachia
Family Amphignathodontidae – sometimes in Hemiphractidae
Genus Flectonotus
Genus Gastrotheca
Family Aromobatidae – sometimes in Dendrobatidae
Genus Allobates
Genus Anomaloglossus
Genus Aromobates
Genus Mannophryne
Genus Rheobates
Family Arthroleptidae
Genus Arthroleptis
Genus Astylosternus
Genus Cardioglossa
Genus Leptodactylodon
Genus Leptopelis
Genus Nyctibates
Genus Scotobleps
Genus Trichobatrachus
Family Brachycephalidae
Genus Brachycephalus - Saddleback toad
Genus Ischnocnema
Family Bufonidae - True toad
Genus Adenomus
Genus Altiphrynoides
Genus Amazophrynella
Genus Amietophrynus - see Sclerophrys
Genus Anaxyrus
Genus Ansonia
Genus Atelopus
Genus Blythophryne
Genus Bufo
Genus Bufoides
Genus Capensibufo
Genus Churamiti
Genus Crepidophryne - see Incilius
Genus Dendrophryniscus
Genus Didynamipus - Four-digit toad
Genus Duttaphrynus
Genus Epidalea - Natterjack toad
Genus Frostius
Genus Incilius
Genus Ingerophrynus
Genus Laurentophryne - Parker's tree toad
Genus Leptophryne
Genus Melanophryniscus
Genus Mertensophryne
Genus Metaphryniscus
Genus Nectophryne
Genus Nectophrynoides
Genus Nimbaphrynoides
Genus Oreophrynella
Genus Osornophryne
Genus Parapelophryne
Genus Pedostibes
Genus Pelophryne
Genus Pseudepidalea
Genus Pseudobufo
Genus Rhinella
Genus Sabahphrynus
Genus Sclerophrys
Genus Schismaderma - African red toad
Genus Truebella
Genus Werneria
Genus Wolterstorffina
Genus Xanthophryne
Family Calyptocephalellidae - sometimes in Bufonidae
Genus Calyptocephalella
Genus Telmatobufo
Family Centrolenidae – Glass frog, including Allophrynidae
Genus Allophryne - Tukeit Hill frog
Genus Celsiella
Genus Centrolene
Genus Chimerella
Genus Cochranella
Genus Espadarana
Genus Hyalinobatrachium
Genus Ikakogi
Genus Nymphargus
Genus Rulyrana
Genus Sachatamia
Genus Teratohyla
Genus Vitreorana
Family Ceratobatrachidae - often listed in Family Ranidae
Genus Alcalus
Genus Cornufer
Genus Liurana
Genus Platymantis
Family Ceratophryidae
Genus Ceratophrys
Genus Chacophrys
Genus Lepidobatrachus
Family Conrauidae - often listed in Family Ranidae
Genus Conraua
Family Craugastoridae - formerly in Dendrobatidae
Genus Barycholos
Genus Bryophryne
Genus Ceuthomantis
Genus Craugastor
Genus Dischidodactylus
Genus Euparkerella
Genus Geobatrachus
Genus Haddadus
Genus Holoaden
Genus Hypodactylus
Genus Lynchius
Genus Niceforonia
Genus Noblella
Genus Oreobates
Genus Phrynopus
Genus Pristimantis
Genus Psychrophrynella
Genus Strabomantis
Genus Yunganastes
Family Dendrobatidae - Poison dart frog
Genus Adelphobates
Genus Ameerega
Genus Andinobates
Genus Colostethus
Genus Dendrobates
Genus Epipedobates
Genus Excidobates
Genus Hyloxalus
Genus Minyobates
Genus Oophaga
Genus Phyllobates
Genus Ranitomeya
Genus Silverstoneia
Family Dicroglossidae - often listed in Family Ranidae
Genus Allopaa
Genus Chrysopaa
Genus Euphlyctis
Genus Fejervarya
Genus Hoplobatrachus
Genus Ingerana
Genus Limnonectes
Genus Minervarya
Genus Nannophrys
Genus Nanorana -
Genus Occidozyga
Genus Ombrana
Genus Quasipaa
Genus Sphaerotheca
Genus Zakerana
Family Eleutherodactylidae - formerly in Brachycephalidae
Genus Adelophryne
Genus Diasporus
Genus Eleutherodactylus
Genus Phyzelaphryne
Family Heleophrynidae - Ghost frog
Genus Hadromophryne - Natal ghost frog
Genus Heleophryne
Family Hemiphractidae
Genus Cryptobatrachus
Genus Flectonotus
Genus Fritziana
Genus Gastrotheca
Genus Hemiphractus
Genus Stefania
Family Hemisotidae
Genus Hemisus - Shovelnose frog
Family Hylidae – including Cryptobatrachidae, Hemiphractidae
Genus Acris – Cricket frog
Genus Agalychnis
Genus Anotheca – Spiny-headed tree frog
Genus Aparasphenodon
Genus Aplastodiscus – Canebrake tree frogs
Genus Argenteohyla
Genus Bokermannohyla
Genus Bromeliohyla
Genus Charadrahyla
Genus Corythomantis
Genus Cruziohyla
Genus Cyclorana
Genus Dendropsophus
Genus Duellmanohyla
Genus Ecnomiohyla
Genus Exerodonta
Genus Hyla
Genus Hylomantis
Genus Hyloscirtus
Genus Hypsiboas
Genus Isthmohyla
Genus Itapotihyla
Genus Litoria
Genus Lysapsus
Genus Megastomatohyla
Genus Myersiohyla
Genus Nyctimantis
Genus Nyctimystes
Genus Osteocephalus – Slender-legged tree frogs
Genus Osteopilus
Genus Pachymedusa – Mexican leaf frog
Genus Pelodryas
Genus Phasmahyla
Genus Phrynomedusa
Genus Phyllodytes
Genus Phyllomedusa
Genus Plectrohyla – Spikethumb frog
Genus Pseudacris – Chorus frog
Genus Pseudis
Genus Ptychohyla
Genus Scarthyla
Genus Scinax
Genus Smilisca – Mexican burrowing tree frog
Genus Sphaenorhynchus
Genus Tepuihyla
Genus Tlalocohyla
Genus Trachycephalus
Genus Triprion
Genus Xenohyla
Family Hylodidae
Genus Crossodactylus
Genus Hylodes
Genus Megaelosia
Family Hyperoliidae
Genus Acanthixalus
Genus Afrixalus
Genus Alexteroon
Genus Arlequinus
Genus Callixalus
Genus Chlorolius
Genus Chrysobatrachus
Genus Cryptothylax
Genus Heterixalus
Genus Hyperolius
Genus Kassina
Genus Kassinula
Genus Morerella
Genus Opisthothylax
Genus Paracassina
Genus Phlyctimantis
Genus Semnodactylus - Weale's running frog
Genus Tachycnemis - Seychelles treefrog
Family Leiuperidae - sometimes in Leptodactylidae
Genus Edalorhina
Genus Engystomops
Genus Physalaemus
Genus Pleurodema
Genus Pseudopaludicola
Family Leptodactylidae – including Cycloramphidae
Genus Adenomera
Genus Crossodactylodes
Genus Edalorhina - see Family Leiuperidae
Genus Engystomops - see Family Leiuperidae
Genus Hydrolaetare
Genus Leptodactylus
Genus Lithodytes
Genus Paratelmatobius
Genus Physalaemus - see Family Leiuperidae
Genus Pleurodem - see Family Leiuperidae
Genus Pseudopaludicola - see Family Leiuperidae
Genus Rupirana
Genus Scythrophrys
Family Mantellidae
Genus Aglyptodactylus
Genus Blommersia
Genus Boehmantis
Genus Boophis
Genus Gephyromantis
Genus Guibemantis
Genus Laliostoma
Genus Mantella
Genus Mantidactylus
Genus Spinomantis
Genus Tsingymantis
Genus Wakea
Family Microhylidae – including Brevicipitidae
Genus Adelastes
Genus Anodonthyla
Genus Aphantophryne
Genus Arcovomer
Genus Asterophrys
Genus Austrochaperina
Genus Barygenys
Genus Callulops
Genus Chaperina
Genus Chiasmocleis
Genus Choerophryne
Genus Cophixalus
Genus Cophyla
Genus Copiula
Genus Ctenophryne
Genus Dasypops
Genus Dermatonotus
Genus Dyscophus
Genus Elachistocleis
Genus Gastrophryne
Genus Gastrophrynoides
Genus Genyophryne
Genus Glyphoglossus
Genus Hamptophryne
Genus Hoplophryne
Genus Hylophorbus
Genus Hypopachus
Genus Kalophrynus
Genus Kaloula
Genus Liophryne
Genus Madecassophryne
Genus Mantophryne
Genus Melanobatrachus
Genus Metamagnusia
Genus Metaphrynella
Genus Microhyla
Genus Micryletta
Genus Mini
Genus Myersiella
Genus Mysticellus - Franky's narrow-mouthed frog
Genus Oninia
Genus Oreophryne
Genus Otophryne
Genus Oxydactyla
Genus Paedophryne
Genus Paradoxophyla
Genus Parhoplophryne
Genus Phrynella
Genus Phrynomantis
Genus Plethodontohyla
Genus Pseudocallulops
Genus Rhombophryne
Genus Scaphiophryne
Genus Sphenophryne
Genus Stereocyclops
Genus Stumpffia
Genus Synapturanus
Genus Uperodon
Genus Vietnamophryne
Genus Xenorhina
Family Myobatrachidae - including Limnodynastidae, Rheobatrachidae
Genus Adelotus - Tusked frog
Genus Arenophryne
Genus Assa
Genus Crinia
Genus Geocrinia
Genus Heleioporus
Genus Lechriodus
Genus Limnodynastes
Genus Metacrinia
Genus Mixophyes - Barred frogs
Genus Myobatrachus
Genus Neobatrachus
Genus Notaden
Genus Opisthodon
Genus Paracrinia - Haswell's frog
Genus Philoria
Genus Pseudophryne
Genus Rheobatrachus - Gastric-brooding frog
Genus Spicospina
Genus Taudactylus
Genus Uperoleia
Family Nasikabatrachidae - often listed in Family Sooglossidae
Genus Nasikabatrachus
Family Nyctibatrachidae - often listed in Family Ranidae
Genus Astrobatrachus
Genus Lankanectes
Genus Nyctibatrachus
Family Petropedetidae - often listed in Family Ranidae
Genus Arthroleptides
Genus Ericabatrachus
Genus Petropedetes
Family Phrynobatrachidae - often listed in Family Ranidae
Genus Phrynobatrachus
Family Pseudidae
Genus Pseudis - see Family Hylidae
Family Ptychadenidae - often listed in Family Ranidae
Genus Hildebrandtia
Genus Lanzarana
Genus Ptychadena
Family Pyxicephalidae - often listed in Family Ranidae
Genus Amietia
Genus Anhydrophryne
Genus Arthroleptella
Genus Aubria
Genus Cacosternum
Genus Microbatrachella - Micro frog
Genus Natalobatrachus - Natal diving frog
Genus Nothophryne
Genus Poyntonia
Genus Pyxicephalus
Genus Strongylopus
Genus Tomopterna
Family Ranidae – True frog, including Ceratobatrachidae, Dicroglossidae, Micrixalidae, Nyctibatrachidae, Petropedetidae, Phrynobatrachidae, Ptychadenidae, Pyxicephalidae
Genus Afrana
Genus Allopaa - see Family Dicroglossidae
Genus Amietia - see Famlily Pyxicephalidae
Genus Amolops
Genus Anhydrophryne - see Famlily Pyxicephalidae
Genus Arthroleptella - see Famlily Pyxicephalidae
Genus Arthroleptides - see Famlily Petropedetidae
Genus Aubria - see Famlily Pyxicephalidae
Genus Babina - sometimes included in Rana
Genus Batrachylodes
Genus Cacosternum - see Famlily Petropedetidae
Genus Ceratobatrachus - see Family Ceratobatrachidae
Genus Chaparana - see Family Dicroglossidae
Genus Chrysopaa - see Family Dicroglossidae
Genus Clinotarsus - formerly in Rana, includes Nasirana
Genus Conraua - see Family Conrauidae
Genus Dimorphognathus - see Phrynobatrachus
Genus Ericabatrachus - see Famlily Petropedetidae
Genus Euphlyctis - see Family Dicroglossidae
Genus Fejervarya - see Family Dicroglossidae, formerly in Rana, paraphyletic
Genus Glandirana - formerly in Rana
Genus Hildebrandtia
Genus Hoplobatrachus - see Family Dicroglossidae
Genus Huia - polyphyletic
Genus Hylarana - formerly in Rana
Genus Humerana
Genus Indirana
Genus Ingerana - see Family Dicroglossidae
Genus Lankanectes - see Family Nyctibatrachidae
Genus Lanzarana - see Family Ptychadenidae
Genus Limnonectes - see Family Dicroglossidae
Genus Lithobates - formerly in Rana
Genus Meristogenys - might belong in Huia
Genus Micrixalus
Genus Microbatrachella - see Family Pyxicephalidae
Genus Minervarya - see Family Dicroglossidae
Genus Nannophrys - see Family Dicroglossidae
Genus Nanorana - see Family Dicroglossidae
Genus Natalobatrachus - see Family Pyxicephalidae
Genus Nothophryne - see Family Pyxicephalidae
Genus Nyctibatrachus - see Family Nyctibatrachidae
Genus Occidozyga - see Family Dicroglossidae
Genus Odorrana - formerly in Rana
Genus Paa - see Family Dicroglossidae
Genus Palmatorappia - see Family Ceratobatrachidae genus Cornufer
Genus Pelophylax - formerly in Rana, probably paraphyletic
Genus Petropedetes - see Family Petropedetidae
Genus Phrynobatrachus - see Family Phrynobatrachidae
Genus Phrynodon - see Family Phrynobatrachidae
Genus Platymantis - see Family Ceratobatrachidae
Genus Pseudoamolops - see Rana
Genus Poyntonia - see Family Pyxicephalidae
Genus Pterorana - Indian flying frog
Genus Ptychadena - see Family Ptychadenidae
Genus Pyxicephalus - see Famlily Pyxicephalidae
Genus Rana
Genus Sanguirana - formerly in Rana
Genus Sphaerotheca - see Family Dicroglossidae
Genus Staurois
Genus Strongylopus - see Famlily Pyxicephalidae
Genus Tomopterna - see Famlily Pyxicephalidae
Family Ranixalidae - sometimes in Ranidae
Genus Indirana
Family Rhacophoridae
Genus Beddomixalus
Genus Buergeria
Genus Chiromantis
Genus Feihyla
Genus Ghatixalus
Genus Gracixalus
Genus Kurixalus
Genus Liuixalus
Genus Mercurana
Genus Nasutixalus
Genus Nyctixalus
Genus Philautus
Genus Polypedates
Genus Pseudophilautus
Genus Raorchestes
Genus Rhacophorus
Genus Taruga
Genus Theloderma
Family Rhinodermatidae – sometimes in Cycloramphidae
Genus Rhinoderma
Family Sooglossidae
Genus Sechellophryne
Genus Sooglossus
Family Strabomantidae - some formerly in Brachycephalidae, all listed in Craugastoridae
Genus Atopophrynus
Genus Barycholos
Genus Bryophryne
Genus Dischidodactylus
Genus Euparkerella
Genus Geobatrachus
Genus Holoaden
Genus Hypodactylus
Genus Lynchius
Genus Niceforonia
Genus Noblella
Genus Oreobates
Genus Phrynopus
Genus Pristimantis
Genus Psychrophrynella
Genus Strabomantis
Order Urodela
Salamanders
Suborder Cryptobranchoidea
Family Cryptobranchidae - Giant salamander
Genus Andrias
Genus Cryptobranchus - Hellbender
Family Hynobiidae - Asiatic salamander
Genus Batrachuperus
Genus Hynobius
Genus Liua
Genus Onychodactylus
Genus Pachyhynobius
Genus Paradactylodon
Genus Pseudohynobius
Genus Protohynobius - Puxiong salamander
Genus Ranodon
Genus Salamandrella
Suborder Salamandroidea
Family Ambystomatidae
Genus Ambystoma - Mole salamander
Family Amphiumidae
Genus Amphiuma
Family Dicamptodontidae
Genus Dicamptodon - Pacific giant salamander
Family Plethodontidae
Genus Aneides - Climbing salamander
Genus Atylodes - Brown cave salamander
Genus Batrachoseps - Slender salamander
Genus Bolitoglossa
Genus Bradytriton
Genus Chiropterotriton
Genus Cryptotriton
Genus Dendrotriton
Genus Desmognathus
Genus Ensatina
Genus Eurycea - Brook salamander
Genus Gyrinophilus
Genus Hemidactylium - Four-toed salamander
Genus Hydromantes
Genus Karsenia - Korean crevice salamander
Genus Nototriton
Genus Nyctanolis
Genus Oedipina
Genus Parvimolge
Genus Phaeognathus - Red Hills salamander
Genus Plethodon - Woodland salamander
Genus Pseudoeurycea
Genus Pseudotriton
Genus Speleomantes
Genus Stereochilus - Many-lined salamander
Genus Thorius
Genus Urspelerpes
Family Proteidae
Genus Necturus
Genus Proteus - Olm
Family Rhyacotritonidae
Genus Rhyacotriton - Torrent salamander
Family Salamandridae
Genus Calotriton
Genus Chioglossa - Gold-striped salamander
Genus Cynops - Fire belly newts
Genus Echinotriton
Genus Euproctus
Genus Ichthyosaura - Alpine newt
Genus Lissotriton
Genus Lyciasalamandra
Genus Mertensiella - Caucasian salamander
Genus Neurergus
Genus Notophthalmus
Genus Ommatotriton
Genus Pachytriton
Genus Paramesotriton
Genus Pleurodeles
Genus Salamandra
Genus Salamandrina
Genus Taricha
Genus Triturus
Genus Tylototriton
Family Sirenidae
Genus Pseudobranchus - Dwarf siren
Genus Siren
Superorder Gymnophiona
Order Apoda
Caecilians
Family Caeciliidae
Genus Boulengerula - see Family Herpelidae
Genus Brasilotyphlus - see Family Siphonopidae
Genus Caecilia
Genus Dermophis - see Family Dermophiidae
Genus Gegeneophis - see Family Indotyphlidae
Genus Geotrypetes - see Family Dermophiidae
Genus Grandisonia
Genus Gymnopis - see Family Dermophiidae
Genus Herpele - see Family Herpelidae
Genus Hypogeophis - see Family Indotyphlidae
Genus Idiocranium - see Family Indotyphlidae
Genus Indotyphlus - see Family Indotyphlidae
Genus Luetkenotyphlus - see Family Siphonopidae
Genus Microcaecilia
Genus Mimosiphonops - see Family Siphonopidae
Genus Oscaecilia
Genus Parvicaecilia
Genus Praslinia - see Family Indotyphlidae
Genus Schistometopum - see Family Dermophiidae
Genus Siphonops - see Family Siphonopidae
Family Chikilidae
Genus Chikila
Family Dermophiidae
Genus Dermophis
Genus Geotrypetes
Genus Gymnopis
Genus Schistometopum
Family Herpelidae
Genus Boulengerula
Genus Herpele
Family Ichthyophiidae
Genus Caudacaecilia
Genus Ichthyophis
Genus Uraeotyphlus
Family Indotyphlidae
Genus Gegeneophis
Genus Grandisonia - see Family Caeciliidae
Genus Hypogeophis
Genus Idiocranium - Makumuno Assumbo caecilian
Genus Indotyphlus
Genus Praslinia - Praslin's caecilian
Genus Sylvacaecilia
Family Rhinatrematidae
Genus Epicrionops
Genus Rhinatrema
Family Scolecomorphidae
Genus Crotaphatrema
Genus Scolecomorphus
Family Siphonopidae
Genus Brasilotyphlus
Genus Caecilita - see Microcaecilia
Genus Luetkenotyphlus
Genus Microcaecilia
Genus Mimosiphonops
Genus Parvicaecilia - see Family Caeciliidae
Genus Siphonops
Family Typhlonectidae
Genus Atretochoana
Genus Chthonerpeton
Genus Nectocaecilia
Genus Potamotyphlus
Genus Typhlonectes
See also
Amphibian
Herping
Genera
Amphibians
Amphibians
Amphibian genera | List of amphibian genera | [
"Biology"
] | 4,659 | [
"Lists of biota",
"Lists of animals",
"Animals"
] |
61,388,491 | https://en.wikipedia.org/wiki/D-Amino%20acid | {{DISPLAYTITLE:D-Amino acid}}
D-Amino acids are amino acids where the stereogenic carbon alpha to the amino group has the D-configuration. For most naturally-occurring amino acids, this carbon has the L-configuration. D-Amino acids are occasionally found in nature as residues in proteins. They are formed from ribosomally-derived D-amino acid residues.
Amino acids, as components of peptides, peptide hormones, structural and immune proteins, are the most important bioregulators involved in all life processes along with nucleic acids, carbohydrates and lipids. "Environmental ᴅ-amino acids are thought to be derived from organic diagenesis such as racemization and release from bacterial cell walls and even from microbial production."
Discovery
Their discovery was in the 1950s. "Auclair and Patton (1950) first reported their presence in the blood of insects and mollusks". They also have been identified in various mammalian tissues. The two major types of D-amino acids synthesized in and by mammals are D-aspartic acid (D-Asp) and D-serine (D-Ser). "D-Asp is present in vertebrates and invertebrates and is involved in the development of both the nervous and endocrine systems". An immense amount of D-Ser can also be detected in the brain, wherein it composes a significant regulatory role in the development of the "central nervous system and is closely associated with learning, memory, and mammalian behavior." A great amount of D-Ser, has also been "detected in human urine; it plays a regulatory role in pathogenic gene expression in the urinary system." Furthermore, they have also been noticed in certain tissues of some marine invertebrates, and "might be involved in regulating osmotic pressure." It is still unclear however, on as to whether they are absorbed from seawater, or are made by the organisms themselves. They have also been identified in plants. A number of D-amino acids also constrain the growth of plants, "while some plants can absorb and metabolize or assimilate ᴅ-amino acids".
Structure and general properties
L- and D-amino acids are usually enantiomers. The exceptions are two amino acids with two stereogenic centers, threonine and isoleucine. Aside from those two special cases, L- and D-amino acids have identical properties (color, solubility, melting point) under many conditions. In the biological context however, which is chiral, these enantiomers can behave very differently. Thus, D-amino acids have low nutritional value, in part because they are not digested well.
They contain a carboxyl group at one end and a side chain group at the other end. They also contain an amine and hydrogen group on opposite ends, depending on which enantiomer one is looking at. They also do attain a chiral carbon center. This is why the molecules can exist in different stereoisomeric forms, and the orientation of the radical groups is what is only different between these enantiomers. on the other hand, contains a carbonyl group and hydroxy (alcohol) groups with the chiral carbon in the center. The orientation is again, different for .
Occurrence and use
Even though D-amino acids are minimal constituents of living organisms, they occur in a broad range of natural environments such as soils, rivers, lakes, marine systems, snow and ice, aerosols and precipitation. They are produced by several marine microbes, which attain important roles in the carbon and energy cycles in the ocean, and contribute as a carbon source to the oceanic carbon reservoir.
D-Amino acid residues occur in cone snails and the venom of the male platypus. They are also abundant components of the peptidoglycan cell walls of bacteria, and D-serine may act as a neurotransmitter in the brain. D-Amino acids are used in racemic crystallography to create centrosymmetric crystals, which, depending on the protein, may allow for easier and more robust protein structure determination.
Gramicidin is a polypeptide made up from mixture of D- and L-amino acids. Other compounds containing D-amino acids are tyrocidine and valinomycin. These compounds disrupt bacterial cell walls, particularly in gram-positive bacteria. , only 837 D-amino acids were found in the Swiss-Prot database out of a total of 187 million amino acids analysed.
Fluorescently labeled D-amino acids, namely FDAAs, have been used for in situ labeling of bacterial peptidoglycan in both gram-positive and gram-negative species.
Bacteria and D-Amino acids
Bacteria probably have the largest capacity to utilize D-amino acids. They have been known to synthesize more than 10 kinds of D-amino acids, most frequently D-alanine and D-glutamate for crosslinking within the peptidoglycan cell wall. In addition, extracellular D-amino acids released from bacteria also control remodeling of the bacterial cell wall and are moreover, thought to function amongst bacteria to accommodate frequently changing environments. Apart from structural function in the bacterial cell wall, D-amino acids have also been associated to growth fitness and to further processes such as biofilm development, spore germination and signaling.
Biosynthesis
At least two enzyme families convert L-amino acids to D-amino acids. Amino-acid racemase, a PLP-dependent enzyme, racemizes amino acids via the formation of the alpha-iminoacids, where the stereogenic center is lost. L-amino-acid oxidases convert L-amino acids to the α-ketoacids, which are susceptible to reductive amination. Some amino acids are prone to racemization, one example being lysine, which racemizes via formation of pipecolic acid.
In peptides, L-amino acid residues slowly racemize, resulting in the formation of some D-amino acid residues. Racemization occurs via deprotonation of the methyne that is alpha to the amido group. Rates increase with pH.
Many D-amino acids found in higher organisms are derived from microbial sources. The D-alanine in peptidoglycans that comprise bacterial cell walls helps its host resist attack by proteolytic enzymes. Several antibiotics, e.g. bacitracin, contain D-amino acid residues.
Previous studies
Phaeobacter sp. JL2886, a deep sea strain that was sequestered in 2012 from a sediment that was 2000 m deep in the South China sea, "was analyzed for its entire genome sequence". In another study, from 56 sediments collected from the deep sea (depth range 800–1500 m), "28 ᴅ-amino acid utilizers" were isolated, in Sagami Bay, Japan. Independent attempts to sequester micro-organisms that grow healthier, due to D-amino acids, has also been done. Most conducted studies and experiments usually also utilize mainly D-alanine, D-aspartate, and D-glutamate, as they signify the most common D-amino acids found in living organisms. Moreover, they also aid as nitrogen sources for many of the fundamental processes involved in the ocean.
References
Zwitterions | D-Amino acid | [
"Physics",
"Chemistry"
] | 1,540 | [
"Biomolecules by chemical classification",
"Matter",
"Amino acids",
"Zwitterions",
"Ions"
] |
73,695,367 | https://en.wikipedia.org/wiki/Mobile%20barrage%20squad | Mobile barrages squad is an element of a combat or operational order in the form of a temporary military formation, which is created from units of engineering troops and army aviation.
The abbreviation for the temporary formation of troops or forces used in service documents is MBS. The main purpose of MBS is to set up mine blast barrages during combat and to destroy transport infrastructure on behalf of friendly forces. Until July 1943 they were referred to simply as a barrage squad.
History
The theoretical foundation for the practical application of MBS was laid in the work "Разрушения и заграждения" (1931) by the Soviet military engineer Dmitry Karbyshev.
During the Second World War (1939 - 1945), and especially the Eastern Front (1941 - 1945), wide use in all types of combat found mines and explosive barrages. For their arrangement in the Battle of Moscow, the Soviet troops for the first time in 1941 were used barrage squads, later called mobile barrage squads, which subsequently were successfully used in other operations of the Red Army of the Soviet Union.
After the Battle of Kursk (1943) on the basis of the experience gained, it was concluded that the army command needed a permanent specialized reserve of engineering units, which would have the means of mechanization of mines, large quantities of mines and explosives of various types. As a consequence, the MBS became a mandatory element of operational structure of the Soviet troops, and in 1942 - 1943 the tactics of MBS in the offensive and defensive were practiced. During the Eastern Front, the Red Army expended more than 70,000,000 different mines, including about 30,000,000 anti-tank mines.
Basic provisions
The composition and equipment of a squad is determined by its objectives in combat or an operation, the availability of available forces and equipment, the composition of the enemy's troops, and the conditions on the ground. When setting a mission, the MBS receives data on the area of location, movement routes, mine lines, and possible courses of action (bands).
On defense, the MBS holds behind the first echelon of its troops in the most likely direction of the enemy's main strike in full readiness to move out to the breakout areas. The primary purpose of the MBS in defensive operations is considered to be:
Rapid erection of mines and explosive barrages and the organization of destruction on the directions of the enemy's breakthrough into the depths of the defense, in the areas of landing of marines and the like;
Covering joints and flanks of their troops with engineering barrages, as well as deployment points for counterattacks and counterstrikes;
Increasing the density of barrages in critical areas of first-echelon unit defense.
On the offensive, the MBS follows the first echelon of troops in readiness to set up barriers at the mines indicated to it.
On the offensive, the tasks of the MBS are usually:
Organizing roadblocks in likely directions of enemy counterattacks and counterattacks;
Covering the flanks of the strike groups and the entry points of the second echelons with engineering barrages;
Setting up barrages in first-echelon units while securing them in captured positions.
An MBS formation can be established not only in the ground forces, but also to solve certain tasks within other branches of the armed forces and branches of the military. For example, in the Navy, the tasks of barrages on the high seas are performed by barrage ship units. In the Strategic Rocket Forces of Russia, units are formed to cover approaches to the facilities of the position area, block enemy reconnaissance groups and landing zones of marines. While conventional units and formations usually organize one MBS, troops defending a stretch of coastline create an additional MBS with watercraft or aircraft for placing anti-landing mines in the water. In military formations, two or three MBSs are created, one of which is equipped with helicopter vehicles.
The organizational structure of the armies of NATO member states does not provide for the deployment and use of MBS.
See also
Fougasse
Notes
Bibliography
Руббо Д., Григорьев Б. Подвижные отряды заграждений в битве под Москвой // Армейский сборник : Научно-методический журнал МО РФ. — М.: Редакционно-издательский центр МО РФ, 2016. — No. 11. — p. 25. — ISSN 1560-036X.
External links
Подвижный отряд заграждений. Энциклопедия. Ministry of Defence (Russia).
Пономарёв А. А. Совершенствование инженерного обеспечения боевых действий войск Красной Армии в битвах под Москвой и Сталинградом. Information site «Военно-политическое обозрение» (2013.02.20)
Хасанов Ш. Ф. Бои на подступах к рубежу. Archived November 7, 2016 at the Wayback Machine
Military terminology
Military engineering
Army aviation | Mobile barrage squad | [
"Engineering"
] | 1,241 | [
"Construction",
"Military engineering"
] |
73,696,250 | https://en.wikipedia.org/wiki/Virgin%20Atlantic%20Flight%20024 | Virgin Atlantic Flight 024 was a regularly scheduled Virgin Atlantic passenger flight from Los Angeles, California, to London, United Kingdom. On 5 November 1997, the Airbus A340 was forced to make an emergency landing at London Heathrow Airport after the left main landing gear failed to deploy. During the crash landing, the aircraft was damaged and later repaired. Of the 114 passengers and crew aboard, 7 were lightly injured.
Aircraft
The aircraft involved was an Airbus A340-311, registered G-VSKY with manufacturer serial number 016. It made its first flight on 3 November 1993 and was delivered soon after to Virgin Atlantic on 21 January 1994. At the time of the accident, the aircraft had flown 19,323 hours. It was fitted with four CFM International CFM56-5C2 high-bypass turbofan engines.
Accident
At 05:09 GMT (21:09 local time), flight VS024 departed from runway 24L in Los Angeles after a 19-minute delay. While climbing, the crew noticed that the landing gear was slow to retract. Later, during a routine in-flight systems scan, it was noted that the brake temperature sensor on the inboard rear wheel of the main landing gear had failed, but the flight was otherwise uneventful.
At 15:04 GMT, while on final approach to Heathrow Runway 27L, the crew received an aural "Gear not safe" alert after deploying the landing gear, upon which the crew elected to go around and return to a holding pattern.
The crew decided to fly near the ATC tower to have a controller visually identify any problem. It was found that the left main landing gear was stuck in a partially deployed position. The crew tried to complete several manoeuvres to free the landing gear without success. The crew had planned to touch the runway with the right main landing gear and immediately go around, hoping to shake the landing gear into a locked position but this was not attempted.
When the crew realized that it was impossible to deploy the left main landing gear, the passengers and airport were prepared for an emergency landing. At 16:08 with the aircraft nearly out of fuel a "Mayday" was declaired. The crew chose to land the plane on runway 27L, believing the lopsided aircraft would turn away from airport facilities once on the ground and towards empty space.
As the aircraft came to land, engine 4 struck the runway and the last landing gear burst. Soon after, engines 1 and 2 also struck the ground, bursting into flames. Once the aircraft veered to the left and stopped passengers were evacuated, seven of which suffered minor injuries.
Cause
The accident was caused by the following factors:
Full deployment of the left main landing gear was prevented because the unrestrained end of the No. 6 brake torque rod became trapped in the keel beam structure within the gear bay. It jammed the landing gear in a partially deployed position.
The torque pin that had connected the No. 6 brake torque rod to the wheel brake had disengaged when the landing gear was retracted after takeoff from Los Angeles, allowing the unrestrained rod to pivot freely about the retained end.
The torque pin and its retaining assembly had been subject to higher axial and torsional loads than predicted during aircraft braking in service. These loads were the result of elastic deformation of the wheel axle, brake, and torque rod, and due to assembly without the correct axial clearance as a result of prior undetected displacement of the associated bushes. The precise mode of failure of the retaining assembly bolt, nut, and cotter, could not be ascertained in the absence of these parts.
This design of wheel brake assembly had satisfactorily passed the related wheel brake structural torque test. However, the latter contained no requirement to use a representative axle or other means to reproduce the axle deflections which occur during aircraft braking in service. As a result, the inspection did not require post torque test strip assessment of brake assemblies, in turn resulted in an over stressing deformation which produced component failure.
Aftermath
The aircraft sustained considerable damage, including to three engines and the landing gear. Runway 27L was damaged after the tyres burst.
See also
List of accidents and incidents involving commercial aircraft
LOT Polish Airlines Flight 16
References
External links
Final Report (Archive)
Appendices (Archive)
1997 disasters in the United Kingdom
1997 in London
Airliner accidents and incidents caused by mechanical failure
Aviation accidents and incidents in England
Accidents and incidents involving the Airbus A340
Aviation accidents and incidents in 1997
Airliner accidents and incidents involving belly landings
November 1997 events in the United Kingdom
Virgin Atlantic accidents and incidents | Virgin Atlantic Flight 024 | [
"Materials_science"
] | 940 | [
"Airliner accidents and incidents caused by mechanical failure",
"Mechanical failure"
] |
73,698,775 | https://en.wikipedia.org/wiki/Protoplasma | Protoplasma is a bimonthly peer-reviewed scientific journal covering various aspects of protoplasm research. It is published by Springer Science+Business Media and was established in 1926. The editor-in-chief is P. Nick (University of Karlsruhe).
The journal publishes research articles, reviews, and commentaries related to protoplasm, including its cell structure, signal transduction, biotechnology, and genetic engineering.
Abstracting and indexing
The journal is abstracted and indexed in:
According to the Journal Citation Reports, the journal has a 2021 impact factor of 3.186.
References
External links
English-language journals
Springer Science+Business Media academic journals
Academic journals established in 1926
Molecular and cellular biology journals
Bimonthly journals | Protoplasma | [
"Chemistry"
] | 150 | [
"Molecular and cellular biology journals",
"Molecular biology"
] |
73,699,572 | https://en.wikipedia.org/wiki/HD%20177406 | HD 177406, also known as HR 7223 or rarely 47 G. Telescopii, is a solitary star located in the southern constellation Telescopium. It is faintly visible to the naked eye as a white-hued point of light with an apparent magnitude of 5.95. Gaia DR3 parallax measurements imply a distance of 369 light years and it is currently approaching the Solar System with a heliocentric radial velocity of . At its current distance, HD 177406's brightness is diminished by 0.23 magnitudes due to interstellar dust and it has an absolute magnitude of +0.60.
HD 177406 has a stellar classification of A0 V, indicating that it is an ordinary A-type main-sequence star that is generating energy via hydrogen fusion at its core. It has 2.64 times the mass of the Sun and a radius 2.55 times that of the Sun. It radiates 62.4 times the luminosity of the Sun from its photosphere at an effective temperature of . It has a solar metallicity at [Fe/H] = +0.00 and it is estimated to be 286 million years old, having completed 58.66% of its main sequence lifetime.
References
A-type main-sequence stars
Telescopium
Telescopii, 47
CD-48 12901
177406
093862
7223 | HD 177406 | [
"Astronomy"
] | 295 | [
"Telescopium",
"Constellations"
] |
73,704,274 | https://en.wikipedia.org/wiki/Tensioned%20stone | Tensioned stone is a high-performance composite construction material: stone held in compression with tension elements. The tension elements can be connected to the outside of the stone, but more typically tendons are threaded internally through a drilled duct.
Tensioned stone can consist of a single block of stone, though drill limitations and other considerations mean it is typically an assembly of multiple blocks with grout between pieces. Tensioned stone has been used in both vertical columns (posts), and in horizontal beams (lintels). It has also been used in more unusual stonemasonry applications: arch stabilization, foot bridges, granite flag posts, cantilevered sculptures, a space frame, and staircases.
Tensioned stone has an affiliation with massive precut stone, which is a central technique of modern load-bearing stonemasonry. It is also aligned with mass timber and straw structural insulated panels (SSIPs), which are all reconfigurations of traditional materials for modern construction that involve some pre-fabrication.
Tensioned stone methods
Tensioning is achieved with steel tendons or rods that are either threaded through ducts within the stone elements or attached to the stone externally. For internal tensioning, holes are drilled into the stone elements to form a duct; the tensioning tendon is threaded into the duct.
The most common form of tensioned stone is post-tensioned stone, which also has the longest history. A second method, developed in the early 2020s, is pre-tensioned stone.
As with pre-stressed concrete, the pre- and post-tensioned methods can be used in different contexts: pre-tensioned stone may be more appropriate for prefabrication, while post-tensioning may be more suitable for on-site assembly.
Post-tensioned stone
For post-tensioning, once the stone components are in place, the tendons are tensioned using hydraulic jacks, and the force is transferred to the stone through anchorages located at the ends of the tendons, usually in combination with a plate. The tensioning process imparts a compressive force to the stone, which improves its capacity to resist tensile stresses that could otherwise cause cracking or failure.
Pre-tensioned stone
In pre-tensioned stone, the tendon (a steel rod) is held in tension with jacks while the remaining cavity in the duct is filled with epoxy grout. After the epoxy has set, the ends of the rod are released from the jacks, placing the stone under compression. A structural difference between pre- and post-tensioned stone is that, in the former, the tension element is adhered to the stone along its length, so compression is applied to the stone along the length of the duct, while in post-tensioned stone the pressure is applied through the end plates.
Rationale
Increased strength
Stone has great compressive strength, so is ideal in compressive structures like stone arches.
However, it has relatively weak flexural strength (compared to steel or wood), so in isolation cannot be safely used in wide spans under tension.
For concrete, this problem has been long solved: in addition to conventional tensile reinforcement, engineers developed prestressed concrete methods starting around 1888. Such tension-reinforced concrete applications combine compressive strength with pre-stressed tensile compression for combined strength much greater than either of the individual components, and have been in wide use for decades. One of the early concrete engineers Eugène Freyssinet improved concrete pre-stressing methods, and it is claimed that he also applied post-tensioned concrete methods to stone. As for concrete, post-tensioning maintains stone in compression, thereby increasing its strength.
Energy use and carbon emissions
Stone is 'natural precast concrete' so only needs to be cut (and strength tested) and tensioned prior to use in construction. Compared to concrete and steel, post-tensioned stone production has dramatically lower energy costs, with concomitant lower carbon emissions.
Applications
Post-tensioned stone has potential to replace steel-reinforced concrete in some contexts, as, according to structural engineer Steve Webb "a post-tensioned stone beam is as strong as steel". "Post-tensioning offers new potential for the revival of masonry as a structural material". Post-tensioned stone has the potential to be used in conjunction with massive precut stone in a range of designs.
In 2020, post-tensioned stone was featured prominently in "The New Stone Age" an exhibition at The Building Centre.
Architect James Simpson writes:
Benefits
Structural benefits
Avantages of tensioned stone relative to reinforced concrete.
Strength. Compared to standard concrete, many types of stone have increased compressive and tensile strength; this property contributes to the increased strength of the prestressed stone assembly (relative to concrete).
Slenderness. Less bulky beams, due to stone's greater compressive strength compared to concrete.
Durability offered by the stone's resistance to weather conditions. This reduces maintenance costs.
Aesthetics. Instead of cladding concrete in stone, the load-bearing stone has the appearance of stone.
Reduced embedded carbon. Post-tensioned stone causes the emission of <1/3rd of carbon dioxide greenhouse gas relative to concrete.
Lower cost. A study of a 30-storey office block found that using PT stone floor panels was cheaper than concrete floors. Subsequent studies by Groupwork found that stone would be cheaper than concrete on most architectural projects (except for box girder bridges), but these studies were not published.
Avantages of tensioned stone relative to untensioned stone.
Reduced material usage. By enhancing the structural performance of stone, post-tensioning allows for the use of thinner stone slabs or walls, reducing the overall material requirements and associated costs.
Expanded design options. Tensioning provides additional design options, allowing architects, engineers, and sculptors to create more innovative and complex structures that would be difficult to achieve with traditional stone construction methods.
Seismic Resilience. Compared to conventional stone, PT stone structures can have improved seismic performance, as the compressive forces could help to maintain the integrity of the structure during ground motion.
Operational advantages
Compared to conventional stonemasonry, post-tensioned stone has substantial structural and weight benefits. In addition, compared to standard stonemasonry, post-tensioned stone preassembly has at least three operational advantages
Pre-assembly of the pieces can be done at ground level, reducing cost and improving safety.
Easier review of the assembly, including testing strength and waterproofing of the mortar.
Easier to schedule tasks, as the prefabricated post-tensioned stone assemblies can be stored before using.
Challenges facing adoption
The wide adoption of post-tensioned stone currently faces a number of challenges, including:
Load-bearing stone's cultural affiliation with traditional architecture.
Confusion with the use of cosmetic stone in high-end luxury construction and the perception of high cost.
Limited knowledge amongst most structural engineers, beyond elite firms like Arup Group, Buro Happold, and Webb Yates. Structural engineering training does not include stone. This is changing with increased attention from the Institution of Structural Engineers
The absence of international standards for engineering with stone.
Lack of stonemasons with knowledge of tensioned stone methods. Lack of concrete workers with prestressing knowledge who also work with stone.
Absence of a large-scale industry for pre-fabricated PT stone.
By analogy with precast concrete, a lack of manufactured modular PT stone components.
The high cost of some early high-profile post-tensioned stone projects, notably Portcullis House.
Shortage of dimension-stone quarries that do routine strength testing and can give strength certificates for their stone components.
The need to develop better CAD-CAM software and hardware for automated CNC stone cutting of precise shapes.
In the early 2020s, the dimension-stone industry in most countries was structured almost entirely for tiles and cladding.
Existing workflows with concrete create a barrier to entry to a new material, which does not have the economies of scale of a new material like stone.
Unclear how to determine the design strength of stone, versus a homogenized material like concrete.
History
Post-tensioned stone has been used in a range of applications. After experimental use in the 1990s, its application increased in the early 2020s in part due to awareness of the high carbon emissions associated with concrete.
Post-tensioned stone footbridges with spans up to 40 m have been built in Japan, Switzerland, Germany, and Spain, and are sold commercially in spans of up to 20 m by Kusser Granitwerke.
Early uses of post-tensioned masonry
While post-tensioned stone has only been used in new construction applications since the 1990s, post-tensioned masonry more generally dates back to at least the early 1800s: "In 1825 a posttensioning method for tunnelling under the River Thames was utilized in England. The project involved the construction of vertical tube caissons of 15m diameter and 21 m height. The 0.75m thick brick walls were reinforced and posttensioned with 25mm diameter wrought iron rods.".
Seismic post-tensioning of brick and stone masonry buildings with steel bolts dates from at latest the 19th century, including following the Charleston earthquake of 1883, and on buildings in seismic regions of Italy. Seismic post-tensioning of masonry is done with considerably lower tension than pre-stressed concrete or modern tensioned stone.
In the mid-20th century, the Sydney Opera House shells were constructed from pre-cast concrete masonry beams that were assembled into a pointed-arch vault using post-tensioning. By 1982, post-tensioned masonry was sufficiently widespread to fill a book published by the Institution of Civil Engineers, though this was brick and precast concrete masonry. In 1985 and 1986, structural engineer Remo Pedreschi and others published studies of post-tensioned brick.
1940s–1980s
In 1947, the Compagnons du Devoir tested the concept of post-tensioned stone, finding that an 8 m span could support a 7-t load.
In the 1960s–80s, Kluesner Engineering developed post-tensioned stone for use as external panels. "Early experiments with posttensioned Indiana limestone units were sponsored by the Building Stone Institute in 1967 and by the Indiana Limestone Institute in 1970. In these programs, several posttensioned beams and slabs were fabricated and tested… The advantages of posttensioned stone are much the same as for concrete. It permits the stone to carry larger loads over longer spans than would be possible with conventional units. The stone units can be plant-fabricated in much larger units to span column to column in the building… A few structural applications have been built using beams for such building features as porticoes, where the live loads have been limited to roof loads and wind loads.".
In the 1980s, the Rock of Ages Corporation developed Accu-Tensioned Granite Press Rolls for use in the paper industry. A column of granite was lathed and then drilled along its length, before the placement and tensioning of steel rods.
In the 1980s, the General Post Office of Sydney underwent a restoration that used reinforcement by post-tensioning the sandstone clock tower. As a result of the seismic reinforcement, the Sydney GPO has been claimed as the first post-tensioned stone building. The structural engineering was led by Colin Crisp of McBean and Crisp. "This technique of post tensioning an existing building is a world first and has raised international interest." As retrofitted seismic bolts were used prior, it appears likely that the GPO's priority claim relates to how the structural calculations guided the tendon placement and increased tension forces. "A more than one hundred year old sandstone masonry building, … the GPO Tower will be strengthened with four vertical post-tensioning tendons, 19 diameter 0.5" strands each, and a number of horizontal prestressing bars diameter 35mm at floor levels. ... Special steel chairs will be used to anchor the tendons and spread the anchorage forces of 1,771 kN (400 kips). The anchorages of the unbonded tendons allow for monitoring and adjustment of the tendon forces to compensate volume changes of the sandstone, if necessary."
1990s
The first documented real-world use of post-tensioned stone in a new building was for the Pavilion of the Future, built in Seville for the Universal Exposition in 1992, designed by structural engineers Peter Rice and Tristram Carfrae of Ove Arup and Partners. Rice had worked on the Sydney Opera House, which was a major technical advance in part because of its use of pre-cast concrete masonry beams that were assembled into the pointed-arch superstructure using post-tensioning; this prior use of post-tensioned masonry may have contributed to Rice's use of post-tensioned stone decades later.
Designed and constructed between 1991–2004, the arches of a 6000 sqm Sanctuary of Saint Pio of Pietrelcina by architect Renzo Piano and structural engineering led by Maurizio Milan of Favero & Milan engineers and Arup Group.
Built in 1994, the 34 m-span Inachus footbridge in Oita, Japan uses post-tensioned stone, designed by engineer Mamoru Kawaguchi. "The bridge has a lenticular shape with an arched upper chord and a suspended lower chord, connected to each other by means of web members consisting of steel tubes arranged to form inverted pyramids."
Completed in 1995, Queen's Building at Emmanuel College, Cambridge by Hopkins Architects and Buro Happold with Ove Arup and Partners. "The columns were also used to provide lateral stability to the building and were post-tensioned using stainless steel rods attached directly to the foundations."
Completed in 1999, Punt da Suransuns in Switzerland, a 40 m footbridge designed by civil engineers Jürg Conzett and Gianfranco Bronzini. "Punt da Suransuns is a stress-ribbon bridge with a span of 40 m … constructed with slabs of Andeer granite, which are prestressed over rectangular steel bars … When traversing the bridge the vertical oscillation can be felt, but pedestrians have commented that the bridge is not as flexible as it looks."
Erected in 1999, Southwark Gateway Needle by Eric Parry is made of 25 blocks of Portland stone held 16m high by post-tensioning.
2000s
Completed in 2001, Portcullis House, a building of the UK Parliament, designed by Hopkins Architects. This building represented a setback in PT stone's cost reputation, as the overall building ran overbudget.
Completed in 2002, 30 Finsbury Square was completed by Eric Parry Architects and Whitbybird engineers. "The columns were constructed conventionally and left to set for 7 days prior to post-tensioning.".
In 2004, Kusser Graniteworks starting manufacturing post-tensioned granite–diorite flagpoles.
In 2005, a prototype of the first post-tensioned spiral stone staircase was made; called "Escalier Ridolfi" it was designed by Claudio D'Amato and Giuseppe Fallacara. In 2006, the full-scale Escalier Ridolfi staircase was presented at the Venice Biennale of Architecture, constructed by Ateliers Romeo stonemasons
In 2007, Kusser Granitwerke constructed their first tensioned stone footbridge, in Rosenheim.
Completed in 2009, a building on Southampton Row, designed by Sheppard Robson architects, used post-tensioned stone.
2010s
Starting in 2011, award-winning high-tensile stone staircases for luxury residences were constructed through a collaboration between stonemason Pierre Bidaud and structural engineer Steve Webb,
In 2013, Giuseppe Fallacara and Marco Stigliano demonstrated a "tensegrilithic" prototype, combining stone with steel rods and cables into a tensegrity structure.
From 2019, Webb Yates engineers used extended horizontal stone lintels in residential construction, and proof-of-principle stone flooring panels.
A 330˚ helix staircase, designed by Foster and Partners for the 2019-completed Dolunay Villa in Turkey and constructed by the Stonemasonry Company with Webb Yates.
2020s
In 2020, IABSE awarded the Milne Medal to Steve Webb for his innovations using low-carbon materials in structural engineering, including wood and tensioned stone.
In 2022, Jürg Conzett and Gianfranco Bronzini were awarded the Swiss Grand Award for Art (Architecture) to recognize their body of work, which includes a number of tensioned-stone footbridges, including Punt da Suransuns (1999), the Waterfall bridge along the Trutg dil Flem trail, and Orrido di Cavaglia (2021). Many of their tensioned-stone projects use gneiss, a stone widely quarried in Switzerland.
In 2024, the Royal Academy of Arts summer exhibition displayed a stone–steel space frame (3D truss) made from cored, tensioned cylinders of limestone and steel joints. "Imagine crane masts, bridges or space frames like the Eden Centre and Stadium Australia being formed with stone elements instead of steel. With a world-saving 75 per cent carbon reduction, inherent durability and fire resistance, we can put waste stone to use and make some really pretty structures." -Steve Webb
Due for completion in 2026, the Sagrada Familia cathedral under construction in Barcelona in partnership with the Arup Group uses post-tensioned stone assemblies. "Jordi Faulí, the architect in charge of La Sagrada Familia in Barcelona, has stated that they will implement this technique for 800 panels that form part of the central towers of the basilica; in fact, prestressing will allow for a higher resistance to winds with less weight." Using post-tensioning allows the construction to avoid using stone-cladded concrete and speeds up construction. Structural engineer Tristram Carfrae of Arup is leading the engineering effort.
See also
References
External links
"The New Stone Age exhibition with Steve Webb, Pierre Bidaud and Amin Taha"
Stone as a structural material. Part 3: Post-tensioned stone structures
Post-tensioned bridges | Tensioned stone | [
"Engineering"
] | 3,723 | [
"Construction",
"Stonemasonry"
] |
73,705,308 | https://en.wikipedia.org/wiki/Journal%20of%20Insect%20Behavior | Journal of Insect Behavior is a bimonthly peer-reviewed scientific journal covering various aspects of insect research. It is published by Springer Science+Business Media and was established in 1988. The editors-in-chief are Jeremy Allison (University of Pretoria) and Ring Cardé (University of California).
The journal publishes research articles, reviews, and commentaries related to various aspects of the behavior of insects, including behavioral ecology, spiders, and isopods.
Abstracting and indexing
The journal is abstracted and indexed in:
According to the Journal Citation Reports, the journal has a 2021 impact factor of 1.038.
References
External links
English-language journals
Springer Science+Business Media academic journals
Academic journals established in 1988
Bimonthly journals
Ethology journals
Entomology journals and magazines | Journal of Insect Behavior | [
"Biology"
] | 159 | [
"Ethology",
"Behavior",
"Ethology journals"
] |
73,706,558 | https://en.wikipedia.org/wiki/Gold%20hexafluoride | Gold hexafluoride is a binary inorganic chemical compound of gold and fluorine with the chemical formula . As of 2023, it is still a hypothetical compound that has never been prepared or observed. In 1999, Neil Bartlett stated, "It should exist, if made at low temperature and kept cold."
Potential properties
Like , should be an extremely powerful oxidizer. The compound is calculated to be stable.
References
Gold compounds
Fluorides
Hexafluorides
Hypothetical chemical compounds | Gold hexafluoride | [
"Chemistry"
] | 102 | [
"Inorganic compounds",
"Theoretical chemistry stubs",
"Hypotheses in chemistry",
"Salts",
"Inorganic compound stubs",
"Theoretical chemistry",
"Hypothetical chemical compounds",
"Fluorides"
] |
73,708,520 | https://en.wikipedia.org/wiki/HD%20192827 | HD 192827, also known as HR 7745 or rarely 83 G. Telescopii, is a solitary red hued star located in the southern constellation Telescopium. It has an apparent magnitude of 6.28, placing it near the limit for naked eye visibility. The object is located relatively far at a distance of 1,320 light years based on Gaia DR3 parallax measurements, but it is approaching with a heliocentric radial velocity of . At its current distance, HD 192827's brightness is diminished by 0.19 magnitudes due to interstellar dust and it has an absolute magnitude of −1.07.
HD 192827 has a stellar classification of M1 III, indicating that it is an evolved red giant. It is currently on the asymptotic giant branch, generating energy by fusing hydrogen and helium shells around an inert carbon core. Having exhausted hydrogen at its core, HD 192827 has expanded to 119 times the radius of the Sun and now radiates 1,242 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of . It has a comparable mass to the Sun and has a metallicity of [Fe/H] = −0.24, making it metal deficient.
HD 192827 was first suspected to be variable in 1997 by the Hipparcos satellite. It fluctuates between magnitudes 6.34 and 6.40 in the Hipparcos passband. As of 2004 however, HD 192827 has not been confirmed to be variable.
See also
HD 192886, an F-type main-sequence star located 519.4" away.
References
M-type giants
Asymptotic-giant-branch stars
Suspected variables
Telescopium
Telescopii, 83
CD-48 13509
192827
100151
7745 | HD 192827 | [
"Astronomy"
] | 383 | [
"Telescopium",
"Constellations"
] |
73,709,695 | https://en.wikipedia.org/wiki/Polysaccharide%20A | Polysaccharide A (PSA) is a polysaccharide produced by the Gram-negative bacterium Bacteroides fragilis. B.fragilis produces eight identified distinct capsular polysaccharides, identified by the letters "A" through "H".
PSA colonization of B. fragilis in the gut mucosa induces regulatory T cells and suppresses pro-inflammatory T helper 17 cells. PSA has been shown to protect animals from experimental diseases like colitis, asthma, or pulmonary inflammation. Nonetheless, PSA can be pro-inflammatory as well as anti-inflammatory.
References
Bacteroidia
Gut flora bacteria | Polysaccharide A | [
"Chemistry",
"Biology"
] | 139 | [
"Gut flora bacteria",
"Carbohydrates",
"Bacteria",
"Polysaccharides"
] |
73,713,278 | https://en.wikipedia.org/wiki/Platinum%28II%29%20fluoride | Platinum(II) fluoride is a binary chemical compound of platinum and fluorine with the chemical formula . Some sources claim that its existence is uncertain.
Synthesis
Effect of fluorine on heated platinum wire at 500-600 °C:
Physical properties
The compound forms yellow crystals. Insoluble in water.
Chemical properties
Platinum difluoride decomposes under strong heating:
References
Fluorides,2
Fluorides
Platinum group halides | Platinum(II) fluoride | [
"Chemistry"
] | 92 | [
"Salts",
"Fluorides",
"Inorganic compounds",
"Inorganic compound stubs"
] |
73,713,336 | https://en.wikipedia.org/wiki/Warkworth%20%26%20District%20Museum | The Warkworth & District Museum, also known as the Warkworth Museum, is a local museum in the township of Warkworth in the Auckland Region, New Zealand. The museum focuses on the local history of the Matakana Coast area, especially the kauri logging industry.
Location
The museum is located to the south of the town of Warkworth in Parry Kauri Park, a two hectare kauri tree reserve. The park includes the McKinney kauri which reached a height of 38 metres and is estimated to be around 800 years old. The reserve features a walkway, primarily on boardwalk. The grove of kauri trees has been tended by a local organisation, the Kauri Bushmen's Association, since the 1960s.
History
A museum for the Warkworth area was first discussed at a town meeting in the early 1970s by local residents Jack Keys and Ken McInnes. By 1977, fundraising and permission for the museum had been obtained. The museum incorporated as a society in 1979, opening the following year on 21 September 1980. The museum opened gradually, with the second stage, the two-storey Parry Wing, opening in 1983.
In 1998, the Founders Wing was opened by Governor General Michael Hardie Boys. Over the next seven years, small historical buildings were added to the complex, including the old Warkworth jail, a United States Military army hut from World War II, and the Mahurangi Heads Post Office.
Displays and exhibits
The museum tells the history of the area, including the kauri milling era and a recreation of the town in the early 20th Century. The museum houses many photographs and photographic equipment of Tudor Collins.
The museum stores over 20,000 items.
Gallery
References
External links
Warkworth Museum website
Agathis
Kauri gum
Museums in the Auckland Region
Local museums in New Zealand
Logging in New Zealand
Rodney Local Board Area
1980 establishments in New Zealand | Warkworth & District Museum | [
"Physics"
] | 384 | [
"Amorphous solids",
"Unsolved problems in physics",
"Kauri gum"
] |
73,713,488 | https://en.wikipedia.org/wiki/Iridium%20trifluoride | Iridium trifluoride is a binary chemical compound of iridium and fluorine with the chemical formula .
Synthesis
Reduction of iridium hexafluoride by metallic iridium:
Decomposition of iridium tetrafluoride by heating at 430–450 °C:
Physical properties
Iridium(III) fluoride forms black hexagonal crystals. It is insoluble in water.
References
Iridium compounds
Fluorides
Platinum group halides | Iridium trifluoride | [
"Chemistry"
] | 94 | [
"Salts",
"Fluorides",
"Inorganic compounds",
"Inorganic compound stubs"
] |
73,713,684 | https://en.wikipedia.org/wiki/Iridium%28IV%29%20iodide | Iridium(IV) iodide is a binary chemical compound of iridium and iodide with the chemical formula .
Preparation
Iridium(IV) iodide can be obtained by reacting dipotassium hexachloroiridate or hexachloroiridic acid with an aqueous solution of potassium iodide.
Properties
Iridium tetraiodide forms black crystals, does not dissolve in water and alcohol. In alkali metal iodide solutions, the compound dissolves easily to give a ruby red solution, forming complex salts.
The compound decomposes when heated:
Uses
Iridium(IV) iodide can be used as a catalyst in organic chemistry.
References
Iridium compounds
Iodides
Platinum group halides | Iridium(IV) iodide | [
"Chemistry"
] | 156 | [
"Inorganic compounds",
"Inorganic compound stubs"
] |
73,716,155 | https://en.wikipedia.org/wiki/Gigaspora%20margarita | Gigaspora margarita is an Arbuscular Mycorrhizal Fungi (AMF) which means it is an obligate symbiont that creates mutualistic relationships with many different plant species. Being an AMF, G. margarita does not produce a fruiting body. All of its mycelium will be found in the soil, associating with plant roots. Though hard to distinguish between different species of AMF, microscopic distinctions can be made. A prominent morphological distinction for species in the Gigasporaceae family is their large sized spores. Gigaspora margarita is characterized by its large, white, pearl-like spores found anywhere from 260 - 400 micrometers. This is where it gets its name as margarita in Latin means pearl.
Associating with many plants, Gigaspora margarita has been found in diverse regions across the globe. In culture, G. margarita has been found to associate with onion, tomato, soy beans, corn, and clover although this list is probably a lot longer. Furthermore, G. margarita also associates with endobacteria making it a metaorganism that serves as a connection of three different kingdoms (plant, bacteria, fungus). Strains of G. margarita isolated without the endobacteria are possible indicating an asymmetric association between the fungi and the endobacteria. However these, ‘cured’ strains of G. margarita do not interact with its associated plants as well as strains with the endobacteria.
Morphology
Arbuscular Mycorrhizal Fungi can be hard to distinguish since they do not produce fruiting bodies and their entire lifecycle is completed below ground. Researchers distinguish species by looking at their microscopic morphologies and genetics.
Mycorrhiza
Arbuscular Mycorrhizal Fungi are characterized by their intracellular arbuscules they form within the associated plant's roots. These arbuscules can come in many different variations with no one looking identical to another. This makes it hard for them to be used as a classification tool. Arbuscules are bush-like structures where they have branches hyphae forming from a swollen hyphal base. Oftentimes, the hyphae of AMF will stain blue using trypan blue dye.
Spore morphology
Gigaspora margarita is distinguished primarily by the morphology of its spores. Young spores are often salmon colored and will become pearly white to yellow-brown at maturity. A mature spore has three cell wall layers (L1, L2, L3):
L1 is the outermost layer which forms the rigid and smooth shell of the spore. It is also pale brownish to yellow and is 1.6 - 2.4 micrometers thick.
L2 is the middle layer that consists of hyaline sub-layers called laminae. These layers increase in number with maturity. The thickness of the L2 layer is highly variable even within the same spore. It can range anywhere from 14 to 23 micrometers. It also has a brown to brownish yellow tint when mounted with PVLG fluid and will turn a dark reddish brown to dark reddish purple if it is stained with Melzer's reagent.
L3 is the innermost layer that is impossible to distinguish from the L2 layer unless the ultrastructure is looked at. Basically, the L3 layer is more electron dense than the L2 layer. The L3 layer forms warts (aka papillae) on its inner surface in clusters. These clusters are an indication of where a germ tube will form.
Auxiliary cells
Gigaspora margarita also has auxiliary cells produced on tightly wound hyphae. These cells are spikey in appearance and are found in clusters of 4-20. Auxiliary cells are found in all species classified under the Gigasporaceae family so while they do not specifically distinguish G. margarita, they are a good indicator that a certain AMF species is in the Gigasporaceae family.
Genome
Gigaspora margarita has a peculiar genetic makeup as its genome consist of around 831 Mega base pairs (Mbp). This is massive compared to the usual fungal genome size that ranges from 8.97 Mb to 177.57 Mb. Furthermore, the 10 largest genomes in the kingdom of fungi belong to species that are either obligate biotrophs, endophytes, or gut fungi. This may seem like an indication that large genomes correlate with better symbiotic relationships with plants however this is not necessarily the case. The composition of the genome of G. margarita is also unique as it is primarily made up of transposable elements (64%). Fungi usually have low levels of transposable elements often only making up 0-25% of the genome. It seems the only other fungi to have large transposable element concentrations are plant pathogens which makes sense because they allow the species to adapt quickly often as a means of overcoming plant defenses. For an AMF fungus, the reasons for having such a large repertoire of transposable elements remains unclear. The genome was also found to consist of gene sequences called Helitrons. Their purpose remains unknown however these indicate that G. margarita may have captured genes from other organisms at some point in time.
Unique features
Endobacteria symbiosis
Gigaspora margarita has a unique ability to associate with a diverse range of endobacteria. Though rare, the ability for Gigaspora margarita to host this intrahyphal bacteria is not completely unique. Many forms of AMF have been shown to associate with bacteria. The primary species of bacteria that associates with G. margarita is named Candidatus Glomeribacter gigasporarum (italicized?). Found in the Burkholderia genus, Ca G gigasporarum has had its entire genome sequenced and found to be a lot smaller than other Burkholderia species. This indicates a reliance on G. sporangium to survive. Ca G gigasporarum has never been found on its own in nature and, so far, can not be isolated in culture. Adding to this hypothesis is the fact that, Ca. G. gigasporarum is vertically transmitted with G. margarita spores. Each spore contains around 250,000 of these bacteria which may be a contributor to the unusually large spores G. margarita produces.
The symbiotic relationship between G. margarita and its endobacteria is asymmetric meaning one of the species can survive without the other while the other species cannot. In this case, G. margarita has been isolated and grown without the presence of endobacteria. Still, endobacteria play an important role in optimizing the relationship between the plant and the fungus. The presence of endobacteria is correlated with a higher antioxidant metabolic rate and lipid biosynthesis in the associated plant. The synthesized lipids would end up being exchanged to G. margarita. Basically, endobacteria are not required for the completion of the G. margarita life cycle however they are major contributors to the health of the interaction between plant and fungus.
Habitat and distribution
Little is known about the habitat and distribution other than it seems to be widespread. G. margarita is found across the globe and has been confirmed in Brazil, USA, Canada, China, Cuba, India, Japan, Mexico, New Zealand, Poland, Syria. Most extensive research on its habitat has been conducted in Brazil where it has been found in all different biomes in the country including areas with high human traffic.
Further information needs to be collected in order to understand the preferable natural environment G. margarita inhabits.
References
Diversisporales
Fungus species | Gigaspora margarita | [
"Biology"
] | 1,589 | [
"Fungi",
"Fungus species"
] |
73,716,265 | https://en.wikipedia.org/wiki/New%20York%20Stem%20Cell%20Foundation | The New York Stem Cell Foundation, or NYSCF, is an American non-profit research institute focused on stem cell research, technology development, and funding researchers. Headquartered on the far west side of Manhattan, New York, NYSCF employs 114 scientists, technicians, engineers, and administrative and other staff, in addition to funding early career investigators and postdoctoral fellows. Since its inception, NYSCF has raised and invested more than $400 million for stem cell research.
Organization
History
NYSCF was founded in New York City by Susan L. Solomon, a lawyer and entrepreneur, and Mary Elizabeth Bunzel, a former journalist, in 2005 to accelerate stem cell-based approaches to researching and treating type 1 diabetes and in response to the refusal of the administration of President George W. Bush to make a major investment in stem cell research. In 2006, NYSCF opened the NYSCF Research Institute – a 500 square foot, one-room independent laboratory located adjacent to Columbia University – as a safe-haven to conduct somatic cell nuclear transfer research through a collaboration with Columbia University and Harvard University.
In 2015, NYSCF signed a 20-year lease to move its headquarters and NYSCF Research Institute laboratories to a renovated 42,000 square foot space at 619 West 54th Street in the former Warner Brothers 'Movie Lab' building, rebranded as the Hudson Research Center by commercial real estate developer and building owner Taconic. Opened in 2017, the new headquarters includes space for a Good Manufacturing Practice facility to manufacture cells for clinical trials. In 2021, New York City announced it would grant NYSCF $6.5M as one of four applied research and development (R&D) facilities to equip an expansion of its Research Institute.
Corporate leadership
The NYSCF is currently led by Jennifer J. Raab, former President of Hunter College. Raab was appointed as President & Chief Executive Officer in January 2024.
The board of directors includes Roy Geronemus, Stephen M. Ross, Stephen Scherr, Kay Unger, Paul Goldberger, and Siddhartha Mukherjee.
Research
High-throughput technologies
In 2015, NYSCF described the development of the NYSCF Global Stem Cell Array, a fully-automated system for high-throughput creation, differentiation, and quality control of stem cell lines. The system saves five to six times the cost of reagents as compared to manual stem cell derivation. The Global Stem Cell Array has been used to conduct research on several patient groups including children with rare diseases, veterans with post-traumatic stress disorder, and Parkinson’s patients.
Stem cell-based research
NYSCF research resulting in the first human stem cell lines from the cells of patients with amyotrophic lateral sclerosis (ALS), commonly known as Lou Gehrig’s disease, was named as Time magazine's top medical breakthrough of 2008 and the number one breakthrough of the year by Science magazine. In 2018, a phase 2 clinical trial for Ezogabine, an epilepsy treatment identified as a possible ALS therapy based on this human stem cell model, was shown to reduce motor neuron excitability in ALS patients.
In 2013, NYSCF researchers created the first patient-specific bone from stem cells and successfully transplanted the grafts into mice.
NYSCF researchers created stem cells and derived neurons from a pair of identical twins, one with Parkinson’s disease and one without, finding their neurons differed in how they produce the neurotransmitter dopamine and the enzyme beta-glucocerebrosidase in addition to differing in a molecular signaling pathway.
NYSCF researchers, in collaboration with researchers at New York University, created astrocytes from human stem cells and showed that in disease-like environments these cells can turn into neuron killers.
Mitochondrial replacement therapy
NYSCF researchers developed mitochondrial replacement therapy in 2012, or MRT, a technique to prevent the mother-to-child transmission of mitochondrial diseases which is now approved for clinical use in the United Kingdom.
Artificial intelligence
With Google Research, NYSCF scientists used the NYSCF Array and artificial intelligence algorithms to identify new cellular features of Parkinson’s disease by analyzing over six million images of skin cells, sampled and expanded from a group of 91 Parkinson’s patients and healthy controls.
Partnerships
Organizations NYSCF has or is currently partnering with include: Google; the Icahn School of Medicine at Mount Sinai, the James J. Peters Veterans Affairs Medical Center, and Yale University School of Medicine; Rush University Medical Center, Harvard Medical School, and Brigham and Women’s Hospital; Johns Hopkins School of Medicine and Bloomberg Philanthropies; and Columbia University Medical Center and the National Eye Institute.
Activism
NYSCF started a working group "Initiative on Women in Science and Engineering" (IWISE) to address gender equality in science and STEM fields. The IWISE working group published seven actionable strategies for institutions to promote gender equity in a 2015 Cell Stem Cell paper. One of these steps is an Institutional Report Card for Gender Equality, which NYSCF created and requires every NYSCF grant applicant to fill out. The results of a 5-year analysis of these report card submissions were published in a 2019 Cell Stem Cell paper defining the extent of gender parity issues in the academic pipeline and opportunities for improvement.
Funding
NYSCF was founded with private philanthropy from individuals and foundations. Notable early funders include former New York City mayor Michael R. Bloomberg; the investor Stanley Druckenmiller and his wife, Fiona; and a foundation founded by the late hedge-fund manager Julian Robertson.
NYSCF hosts an annual fundraising Gala and Science Fair. Past honorees include Janet and Jerry Zucker, Sanjay Gupta, MD; Siddhartha Mukherjee, MD, DPhil; Irving Weissman, MD; Susan and Stephen Scherr; Victor Garber; Derrick Rossi, PhD; Kizzmekia Corbett, PhD; Barney Graham, MD, PhD; Katalin Karikó, PhD; Drew Weissman, MD, PhD; Brooke Ellison; Frank Gehry; and David Rockwell. In 2021 and 2020, NYSCF held virtual Galas both directed by Scott Ellis and hosted by Sanjay Gupta, MD.
In addition to philanthropy, NYSCF also receives funding from grants, partnerships, and collaborations.
Awards
Several awards are administered by the NYSCF. The Robertson Early Career Investigator Awards are given to scientists who have recently launched their own laboratories and provides unrestricted funding over a five-year period to scientists around the world, funded by the Robertson Foundation since 2010. The Druckenmiller Postdoctoral Fellows Awards provide three years of unrestricted funding to postdoctoral stem cell researchers in the tri-state area of New York, New Jersey and Connecticut, and are funded by Stanley and Fiona Druckenmiller.
Notable recipients of NYSCF awards include
References
External links
Official website
Research institutes
Independent research institutes
Scientific research foundations
Stem cell research
Non-profit organizations based in New York City
Medical and health foundations in the United States
Biomedical research foundations | New York Stem Cell Foundation | [
"Chemistry",
"Engineering",
"Biology"
] | 1,435 | [
"Stem cell research",
"Translational medicine",
"Tissue engineering",
"Biotechnology organizations",
"Biomedical research foundations"
] |
73,716,833 | https://en.wikipedia.org/wiki/Isaria%20cicadae | Isaria cicadae is an ascomycete fungus that parasitizes cicada larvae. It forms white and yellow asexual fruiting structures resembling synnema. While mostly being found throughout Asia in warm, humid regions, it has been found on various other continents. It is known in Traditional Chinese Medicine as Chan Hua and commonly called “cicada flower.” Its medicinal uses date back to the fifth century AD in China. It can also be used in various foods and tonics.
Taxonomy
Isaria cicadae is thought to be a cryptic species because of how many different species names have been attributed to it and the controversy over what the correct species name is. I. cicadae was originally described as Isaria cicadae Miq. by Miquel in 1838 until he synonymized it with C. cicadae in 1895. Paecilomyces cicadae was synonymized with C. cicadae in 1974 by Samson. Soon after, S.Z. Shing described the species again as Cordyceps cicadae Shing in 1975, but these are all thought to be generally synonymous. C. cicadae and I. cicadae are both often used in the literature. I. cicadae is thought to be the most current name for the species, although the true taxonomy is still in flux. Other reported synonyms include Cordyceps zhejiangensis, C. sobolifera, C. sinclairii.
Description
Isaria cicadae forms its fruiting structures on the surface of its host, a cicada nymph. The fruiting structure can either cover the entire nymph body or only partially cover it. Sexual structures are not produced on these fruiting structures. Much more information is known about the asexual morph of this fungus because the sexual morph has been reportedly observed once in nature and never in the lab. Its asexual fruiting structures are synnema-like and produce conidiophores and conidia. The fruiting bodies have yellow stalk-looking structures with a white-ish, fluffy tip where the conidiophores are located.
Ecology
Isaria cicadae is an entomogenous fungi that parasitizes the nymphs of its cicada hosts and forms fruiting structures on the surface. These fruiting structures are produced from June–August, and they protrude from the nymph, up through the soil after the fungus kills it. Asexual means of reproduction occur once temperatures rise following sclerotium development and is done so through conidia, dispersed by air and water. It is said that this fungal species is rare and scarce because it propagates slowly and lacks resistance. This could also be due to the fact that it is largely asexual and clonal in nature, as sexual structures have yet to be reliably observed in lab or in nature. Despite this, there is evidence supporting that it is heterothallic being that a study found a truncated MAT1-1-1 type found in the MAT1-2 locus that is not due to asexual fruiting.
Its genome has been sequenced and found to be 33.9Mb including serine proteases and chintinases which target host tissues and are characteristic of other entomopathogenic fungi. The fungus also produces metabolites such as beauvericins and oosporein which have non-selective insecticidal properties. This would suggest that the fungus could infect more than one host, but this has only been seen in the lab on silkworm pupae and beetle wings.
Life cycle
The life cycle of Cordyceps cicadae (synonymous with I. cicadae) in southern China as observed and described by Zha, Ling-Sheng et al. in 2019 follows. During mid-late summer, conidia of I. cicadae attach to the surface of a cicada nymph’s body within the soil which germinate and form germ tubes that can penetrate below the surface and form hyphae. After two to three days of absorbing the cicada’s nutrients and reproducing, they can occupy the entire body. Hyphae turn to mycelia which cause the nymph to die from absorbing water and nutrients and producing mycotoxins. After the nymph is killed, the fungus forms a sclerotium and produce antibiotics to keep the body from rotting. When temperatures rise again, either that year or the following, mycelia are produced once more to form synnemata that eventually break through the soil to grow above ground. The synnema branches to form multiple conidiophores and chained conidia. The conidia are dispersed by air or water, leading them back to the soil, where they use water flow to infiltrate the soil until they make contact with another nymph and infect.
Habitat and distribution
Isaria cicadae is found in warm, humid, low-elevational regions (below 2,500m), on cicada nymphs in sunny soils. Habitats that fit these criteria include bamboo, broad-leaved, coniferous, and broad-leaved mixed forests. They are mostly found in China, but have also been found throughout Asia, Europe, and North America, with some studies showing other continents as well.
Medicinal properties
Isaria cicadae/C. cicadae is one of the oldest, most valued and well-known forms of Traditional Chinese Medicine, dating back to the fifth century AD. When used as a medicine, it is referred to as Chan Hua. Many of its medicinal properties relate it to the more commonly used Cordyceps sinensis and Cordyceps militaris, making it a potential substitute for these highly sought after medicinal fungi. Obstacles to using I. cicadae on a larger scale alongside its relatives C. sinensis and C. militaris include its scarcity and its cryptic taxonomy which make it difficult to study, cultivate, and harvest. It has been shown to be helpful for a multitude of health issues and concerns and nonsignificant toxicity has been reported meaning it is thought to be safe to use as treatment. On the other hand, oosporein, which is produced by the fungus, has been shown to cause issues in some species including birds and chickens, canines. Oxalic acid also produced by the fungus could be cause for kidney stone disease in high levels.
Putative active functions
Treatment of childhood convulsion
Analgesic activity and sedative function
Anti-fatigue effects
Antitumor activity
Amelioration of renal function
Immunomodulatory effects
Immunoregulatory
Medicinal uses and treatments
Malaria
Palpitations
Cancer
Fever
Diabetes
Eye diseases
Dizziness
Chronic kidney diseases
Acute conjunctivitis
Chronic blepharitis, dacryocystitis, and pterygium
Other uses
Improving eyesight, removing eye cloudiness
Neuroprotection
Promoting eruption
Liver and kidney protection
Blood fat reduction
Chemical constituents
Chemicals isolated from I. cicadae/ C. cicadae include nucleotides and nucleosides, sterols (ergosterol, mannitol), cyclic dipeptides, sugars, polysaccharides, fatty acids, amino acids, aromatic compounds, galactomannan, adenosine, uridine, inosine, guanosine, cyclopeptides, myriocin, and inorganic elements.
References
Cordycipitaceae
Fungus species | Isaria cicadae | [
"Biology"
] | 1,556 | [
"Fungi",
"Fungus species"
] |
73,716,944 | https://en.wikipedia.org/wiki/Mucor%20fragilis | Mucor fragilis is an endophytic fungus that causes the mold that can be found on grapes, pole beans, loquat, and on the roots of medicinal plants like Radix pseudostellariae. It belongs to the order Mucorales and phylum Mucoromycota. The observed symptoms showed the presence of fluffy and soft fungal mycelium with white to dark brown discoloration that deteriorated the beans and grapes quality.
Taxonomy
Mucor fragilis was described by Bainier in 1884.
Description
Mucor fragilis is described to have colonies that vary in color from white and reverse white to light gray. Mucor fragilis reproduces asexually and the sporangiophores are found as two types: simple and sympodially branched. Sporangiophores are mostly sympodially branched and grow to a width of around 6–12 μm and have a variable length. These sporangiophores have globose to subglobose, multispored, light yellow sporangia on them that measure around 24.5–49.5 by 22.5–48 μm. The columellae of Mucor fragilis can be globose to ellipsoid, pyriform, or some conical and can measure around 17.5–30 by 16–29.5 μm. The columellae collar is evident.
Habitat and distribution
This species is isolated from soil, insects, fruits, honeycomb, limestone, and plasticized polyvinyl chloride. It is distributed worldwide in places like Australia, Brazil, Bulgaria, China, Czech Republic, Germany, Greece, India, Iran, Kenya, Korea, Lithuania, Mexico, Pakistan, Poland, Portugal, Spain, Switzerland, and the United States. It is known in 3 of the 26 states in Brazil.
Ecology
Mucor fragilis is causing rot on lots of plant species in China and Pakistan. It has been found on grapes in five different locations of fruit markets after harvest in Pakistan and has causes a decline in the market value of grapes. Thyme oil has been found to potentially increase the shelf-life of these grapes. Also in Pakistan, Mucor fragilis has been causing rot in seychelles pole beans. This is the first time this fungus has been seen on pole beans and is causing urgency to control this fungus so it does not spread. In China, Mucor fragilis has been found on one of China's highly prized medicinal plants (Radix pseudostellariae). This is also the first report of Mucor fragilis causing rot on this plant and could result in loss of production of this medical plant. Mucor fragilis was found on deceased adult reproductive female brown widow spiders (Latrodectus geometricus) in North Central Florida. Spiders first showed signs of reduced foraging behavior and then started to die, this confirms that Mucor fragilis is pathogenic to these spiders. Mucor fragilis releases spores that can infect species like these spiders in multiple ways such as in their food or wound exposure. A study done on enzymes from Mucor fragilis grown on bovine blood provides a discussion on how this fungus be helpful to study structures on glycoconjugates containing certain glycoproteins. The view is that blood has nutritional value and is wasted when producing meat and the goal was to find a way to reuse this biomass and with a little more research, enzymes of Mucor fragilis may be the answer to the problem.
Bioactive metabolites
Mucor fragilis can produce simultaneously two bioactive metabolites, podophyllotoxin and kaempferol, as its host plant. This is very significant for this fungus as podophyllotoxin is in great demand due to its use as an anticancer and antivirus drug precursor. As the podophyllum plant is endangered, having Mucor fragilis produce podophyllotoxin can help increase the production of podophyllotoxin and also help the endangered podophyllum plant from going extinct. Mucor fragilis is an effective endophytic fungal elicitor as it has shown enhancement features of some primary and secondary metabolites in Salvia miltiorrhiza hairy roots.
References
Mucoraceae
Fungi described in 1884
Fungus species | Mucor fragilis | [
"Biology"
] | 904 | [
"Fungi",
"Fungus species"
] |
73,716,999 | https://en.wikipedia.org/wiki/Torulaspora%20globosa | Torulaspora globosa is a yeast fungus in the genus Torulaspora. This species can be found in the rhizosphere and is beneficial for agricultural activities. Considered a plant growth promoting rhizobacteria, this species helps with plant health maintenance. It is important for biofuel production and is a promising biocontrol agent.
Description
Can use glucose, sucrose, ethanol and other caron sources for growth. Has a round-oval shape, arranges in pairs, has a creamy and shiny appearance on agar. Has a range of size of about 1-7 micrometers n breadth and 2-8 micrometers in length. Divides by multipolar budding. Can utilize ammonia as a nitrogen source. No spores present, asexual nor sexual. No filamentous growth.
Lipid and ethanol generation
Biodiesel is a mixture of mono-alkyl esters of long chain fatty acids can be used instead of regular diesel with superior performance. Recently there has been a search for new ways of producing biodiesel that is not made from food. Yeast strains including Torulaspora produce lipids that are similar in composition to the vegetable oils we use now to synthesize biodiesel. Torulaspora globosa was found to produce around 3.12g/L of usable lipids for days. After nitrogen and sugar sources deplete the yield decreases Zinc seems to play a role in its produced lipids along with nutritional elements. Alongside lipids, T. globosa can undergo fermentation to produce ethanol, another compound we can use as biofuel. It was found to be able to ferment effectively up to 40 degrees Celsius and could tolerate the increased ethanol levels.
Biocontrol
Studies have shown that Torulaspora globosa is a good mycelial growth inhibitor, specifically against Colletotrichum. In vitro tests showed that T. globosa has an antagonistic effect on mycelial growth against the phytopathogenic mold Colletotrichum sublineolum. Results showed hyphal damage caused by the yeast on the agar dishes. T. globosa is considered mycocinogenic, despite not producing any volatile compounds, siderophores, or hydrolytic enzymes.
Plant growth promotion
Decreases root length while increasing biomass of lettuce. This study found that the root length was decreased but the roots exhibited greater branching than before. Shoot biomass was also increased, along with wider and longer leaves.
Produces indole acetic acid which promotes growth of most plants and can solubilize minerals used by the plants.
References
Saccharomycetaceae
Fungi described in 1975
Fungus species | Torulaspora globosa | [
"Biology"
] | 572 | [
"Fungi",
"Fungus species"
] |
60,017,594 | https://en.wikipedia.org/wiki/VIP%20terminal | VIP (Visual Information Projection) terminals are a series of computer terminals by Honeywell/Bull, used to connect to their mainframe systems.
External links
terminals-wiki.org
Honeywell | VIP terminal | [
"Technology"
] | 40 | [
"Computing stubs"
] |
60,017,953 | https://en.wikipedia.org/wiki/Samsung%20Galaxy%20Fold | The Samsung Galaxy Fold is an Android-based foldable smartphone developed by Samsung Electronics. Unveiled on February 20, 2019, it was released on September 6, 2019, in South Korea. The device is capable of being folded open to expose a 7.3-inch tablet-sized flexible display, while its front contains a smaller "cover" display, intended for accessing the device without opening it. With the announcement of the Galaxy Z Flip, Samsung's foldable phones were made part of the Galaxy Z series. This also retroactively applies to the Galaxy Fold.
The Galaxy Fold received mixed pre-release reception, with praise for its innovative design, but criticism over the device's durability and longevity, and it was concluded that the Galaxy Fold was a proof of concept device for early adopters rather than a device suited for the mass market. Due to issues with the device's durability and susceptibility to damage, Samsung announced that it would recall the review units and delay the release of the Galaxy Fold indefinitely while it addressed the problems. Samsung officially detailed its design changes in July and released the phone in September 2019. The company claimed to have sold one million units since launch by December 2019, but Samsung later denied having sold 1 million units, and admitted having reported sales expectations as actual sales.
History
A prototype of the Galaxy Fold (obscured to hide its final design) and its "Infinity Flex Display" was unveiled during a Samsung developers' conference in November 2018, demonstrating the adaptations to Samsung's Android distribution and newly-unveiled One UI software. Google stated that it would work with OEMs to support foldable devices on Android (an effort achieved natively in Android 10).
Delay
After reports surfaced that Samsung had postponed a Chinese launch event and that review units' inner display was breaking, Samsung announced on April 22 that the launch (originally set for April 26) had been delayed indefinitely while they work to fix the issue, with plans to announce the new release date sometime within the coming weeks and that the defective review units are being recalled. Samsung later announced that Galaxy Fold pre-orders would automatically be cancelled if the device had not been shipped by May 31, and the customer had not otherwise confirmed their order. On May 24, 2019, U.S. retailer Best Buy cancelled all pre-orders. AT&T subsequently cancelled pre-orders on June 13, 2019, announcing that it would issue refunds, as well as complimentary US$100 bill credits.
CNET drew comparisons between the postponement and the battery-related recalls of the Galaxy Note 7. On a test by CNET, the Galaxy Fold's hinge only lasted for 120,000 folds (equivalent to 3 years of use) out of the advertised 200,000 folds (equivalent to 5 years of use).
On July 24, 2019, Samsung announced that it was now targeting a September release, and detailed design changes intended to help reinforce the screen and protect the hinge. Caps were added on the top and bottom of the hinge area and the protective layer was extended under the bezel to prevent accidental removal. Samsung also added extra layers of metal under the screen. Samsung also stated that it had reduced the space between the hinge and body of the device.
Samsung issued more detailed care instructions with the new release, advising users against placing items or adhesives on the screen, pressing the screen with hard objects, exposure to liquids or small particles, removing the protective layer, and also warning about placing the phone near items sensitive to magnets. The Verge remarked that the new instructions were akin to "a pharmaceutical ad that has to disclose dozens of side effects". In the United States, select retailers and Samsung stores offered a "Premier Service" for the device, including an orientation session post-purchase, a dedicated customer support line specific to Galaxy Fold-related issues, and the ability to purchase a one-time screen replacement out-of-warranty from one of the aforementioned outlets for US$149 (however, the device still carries a standard one-year warranty).
A version of the device was released exclusively for China Telecom, marketed as the Galaxy W20 5G with a faster Snapdragon 855+ processor and a unique white finish. The W20 went on sale on December 12, 2019; it is available in two colors (Space Silver and Cosmos Black).
Specifications
The Galaxy Fold contains two displays; its front cover contains a small, 4.6-inch display in the center designed for one-handed use, and the device can fold open to expose a 7.3-inch display. Samsung rated the fold mechanism as supporting up to 200,000 uses. The tablet screen contains a large notch in the top-right corner and is coated with a custom multi-layer laminate instead of glass. Its power button contains a fingerprint reader.
The phone uses the Qualcomm Snapdragon 855 processor and contains 12 GB of RAM and has 512 GB of non-expandable storage. Unlike other Samsung devices, the Qualcomm chip is used in all regions instead of only being used in selected markets. The Galaxy Fold also has a 5G-capable variant with a slightly smaller battery.
The device contains two batteries split between the two halves totaling 4380 mAh (4235 mAh on the 5G model). The Galaxy Fold contains 6 cameras, using the same sensors equipped on the Galaxy S10+, including three rear-facing camera lenses (12-megapixel wide angle, 12-megapixel 2x telephoto, and 16-megapixel ultra wide-angle), as well as a 10-megapixel front-facing camera on the cover, and a second 10-megapixel front-facing camera, accompanied by an RGB depth sensor, on the inside screen.
The Galaxy Fold ships with Android 9.0 "Pie" and Samsung's One UI software. An enhanced Multi Window mode is available for the device, supporting up to three app on-screen at once. Apps opened on the smaller screen can expand into their larger, tablet-oriented layouts when the user unfolds the device.
Reception
Digital Trends praised the Fold's software, performance, camera and main screen, while criticizing the price, the front screen design and the lack of water resistance. Chokkattu remarked that "[it's] a lot of fun to use because it's so new", but noted that "it remains technology that's out of reach for most people". CNET felt that the inside of the device felt "toy-like" in contrast to the premium exterior, noting the fragility of its screen, a plastic bezel, a "ridiculous and unnecessarily large" notch, a crease in the screen visible from certain viewing angles, and gaps at the top and bottom of the hinge that were potentially susceptible to dust and debris. The lack of water resistance was also noted, and it was felt that the size of the cover screen made typing difficult. It was concluded that the Galaxy Fold was a "testbed device for developers and the earliest adopters to buy, and for the rest of us to ponder over".
Dieter Bohn of The Verge considered the fold-out tablet screen a "joy" to use, but remarked that its thick form factor and small cover screen made the Galaxy Fold less suited for shorter, frequent uses like a smartphone. He also panned the display for not being as smooth as a glass screen, being susceptible to scratches and blemishes over time, the aforementioned crease, the large notch, a "jelly" distortion between the two sides when scrolling, and having too many potential points of failure. Bohn praised its high-end hardware, and especially its batteries, and felt that multitasking was flexible but inelegant, and buggy with certain apps on transitions between modes. In conclusion, he felt that the Galaxy Fold was "legitimately a marvelous thing to play with", but that the device was more of a status symbol than a legitimate consumer product.
Issues
Review units showed a high rate of display failure; a teardown by iFixit noted that the crease contained noticeable gaps at the top and bottom, making it susceptible to foreign debris coming under the screen. This resulted in "bulges" experienced by multiple reviewers, including Blick, and The Verge—whose screen was damaged in this manner. At Samsung's request, this teardown was removed from the website, although it was later reinstated after the re-release of the Galaxy Fold.
A number of other reviewers damaged the screen by mistakenly removing one of the clear laminate layers that covers it. Samsung advised that the "special protective layer" that coats the screen must not be removed, as doing so may cause damage to the screen. Concerns were raised that consumers may mistake it for a pre-installed screen protector without proper advisories: retail units of the Galaxy Fold did contain a disclaimer. Samsung later stated that it would "thoroughly inspect" the defective review units to investigate the issues. Samsung would later delay the release of the phone, and make numerous changes to the screen in an effort to mitigate the issue.
See also
Samsung Galaxy Note series
Samsung Galaxy Z series
Comparison of smartphones
References
Mobile phones introduced in 2019
Samsung Galaxy
Samsung smartphones
Android (operating system) devices
Foldable smartphones
Mobile phones with multiple rear cameras
Mobile phones with 4K video recording
Discontinued flagship smartphones
Discontinued Samsung Galaxy smartphones | Samsung Galaxy Fold | [
"Technology"
] | 1,946 | [
"Crossover devices",
"Foldable smartphones",
"Discontinued flagship smartphones",
"Flagship smartphones"
] |
60,018,232 | https://en.wikipedia.org/wiki/NGC%203729 | NGC 3729 is a barred spiral galaxy located in the constellation Ursa Major. It is located at a distance of circa 65 million light years from Earth, which, given its apparent dimensions, means that NGC 3729 is about 60,000 light years across. It was discovered by William Herschel on April 12, 1789.
NGC 3729 has a bright nucleus embedded in a bar which measures 0.5 x 0.1 arcminutes. At the end of the bar lies a ring with knots. The outer part of the galaxy is formed by an asymmetric faint nebulosity with condensations. It is possible that the condensation is a disturbed satellite galaxy. In the centre of NGC 3729 is predicted to lie an intermediate-mass black hole, whose mass is estimated to be between 4 and 400 thousands (104.6 ± 1.0 ) based on Ks-band bulge luminosity. The galaxy has an inner ring which emits in far ultraviolet and H-alpha, which are considered to be markers of recent star formation activity.
NGC 3729 is member of the M109 Group which is part of the south Ursa Major groups, part of the Virgo Supercluster. It forms a pair with NGC 3718, which lies 11.5 arcminutes to the west. It is possible the two galaxies interacted in the past.
Although no supernovae have been observed in NGC 3729 yet, a luminous red nova, designated AT 2018hso, was discovered on 31 October 2018 (type LRN, mag. 19.4).
References
External links
Barred spiral galaxies
Peculiar galaxies
Ursa Major
Ursa Major Cluster
3729
06547
35711
Astronomical objects discovered in 1789
Discoveries by William Herschel | NGC 3729 | [
"Astronomy"
] | 359 | [
"Ursa Major",
"Constellations"
] |
60,018,266 | https://en.wikipedia.org/wiki/Arnon%20Avron | Arnon Avron (; born 1952) is an Israeli mathematician and Professor at the School of Computer Science at Tel Aviv University. His research focuses on applications of mathematical logic to computer science and artificial intelligence.
Biography
Born in Tel Aviv in 1952, Arnon Avron studied mathematics at Tel Aviv University and the Hebrew University of Jerusalem, receiving a Ph.D. magna cum laude from Tel Aviv University in 1985. Between 1986 and 1988, he was a visitor at the University of Edinburgh's Laboratory for Foundations of Computer Science, where he began his association with computer science.
In 1988 he became a senior faculty member of the Department of Computer Science (later School of Computer Science) of Tel Aviv University, chairing the School in 1996–1998, and becoming a Full Professor in 1999.
Research
Avron's research interests include proof theory, automated reasoning, non-classical logics, foundations of mathematics. For example, using analytic geometry he proved the Mohr–Mascheroni theorem. In applying mathematical logic in computer science to artificial intelligence, Avron contributed to the theory of automated reasoning with his introduction of hypersequents, a generalization of the sequent calculus. Avron also introduced the use of bilattices to paraconsistent logic, and made contributions to predicative set theory and geometry.
Selected works
Books
Articles
References
1952 births
Living people
Einstein Institute of Mathematics alumni
Israeli computer scientists
Israeli Jews
Israeli mathematicians
Mathematical logicians
Tel Aviv University alumni
Academic staff of Tel Aviv University | Arnon Avron | [
"Mathematics"
] | 303 | [
"Mathematical logic",
"Mathematical logicians"
] |
60,018,290 | https://en.wikipedia.org/wiki/MISP%20Threat%20Sharing | MISP Threat Sharing (MISP), Malware Information Sharing Platform is an open source threat intelligence platform. The project develops utilities and documentation for more effective threat intelligence, by sharing indicators of compromise. There are several organizations who run MISP instances, who are listed on the website.
History
This project started around June 2011 when Christophe Vandeplas had a frustration that way too many Indicators of Compromise (IOCs) were shared by email, or in pdf documents and were not parsable by automatic machines. So at home he started to play around with CakePHP and made a proof of concept of his idea. He called it CyDefSIG: Cyber Defence Signatures.
Mid July 2011 he presented his personal project at work (Belgian Defence) where the feedback was rather positive. After giving access to CyDefSIG running on his personal server the Belgian Defence started to use CyDefSIG officially starting mid August 2011. Christophe was then allowed to spend some time on CyDefSIG during his work-hours, while still working on it at home.
At some point NATO heard about this project. In January 2012 a first presentation was done to introduce them in more depth to the project. They looked at other products that the market offered, but it seemed they deemed the openness of CyDefSIG to be of a great advantage. Andrzej Dereszowski was the first part-time developer from NATO side.
One thing led to another and some months later NATO hired a full-time developer to improve the code and add more features. A collaborative development started from that date. As with many personal projects the license was not explicitly written yet, it was collaboratively decided that the project would be released publicly under the Affero GPL license. This to share the code with as many people as possible and to protect it from any harm.
The project was then renamed to MISP: Malware Information Sharing Project, a name invented by Alex Vandurme from NATO.
In January 2013 Andras Iklody became the main full-time developer of MISP, during the day initially hired by NATO and during the evening and week-end contributor to an open source project.
Meanwhile other organisations started to adopt the software and promoted it around the CERT world (CERT-EU, CIRCL, and many others).
Nowadays, Andras Iklody is the lead developer of the MISP project and works for CIRCL.
As the MISP project expanded, MISP is not only covering the malware indicators but also fraud or vulnerability information. The name is now MISP Threat Sharing, which includes the core MISP software and a myriad of tools (PyMISP) and format (core format, MISP taxonomies, warning-lists) to support MISP. MISP is now a community project led by a team of volunteers.
Funding
The project is funded by the European Union (through the Connecting Europe Facility) and the Computer Incident Response Center Luxembourg.
Intelligence Integration
Indicators of compromise which are managed by MISP may originate from a variety of sources; including internal incident investigation teams, intelligence sharing partners or commercial intelligence sources. Commercial sources with integration to MISP include Symantec's DeepSight Intelligence (now called Broadcom), Kaspersky threat feeds and McAfee Active Response. MISP integrations with open-source and commercial threat intelligence platforms include the ThreatQuotient Platform and EclecticIQ Platform.
References
External links
IETF draft-dulaunoy-misp-taxonomy-format-06
Building and designing MISP: A practical information-sharing tool for cybersecurity and fraud indicators
Privacy Aware Sharing of IOCs in MISP
Data security
Computer security software
Free security software | MISP Threat Sharing | [
"Engineering"
] | 757 | [
"Cybersecurity engineering",
"Data security",
"Computer security software"
] |
60,018,379 | https://en.wikipedia.org/wiki/Bionic%20Leaf | The Bionic Leaf is a biomimetic system that gathers solar energy via photovoltaic cells that can be stored or used in a number of different functions. Bionic leaves can be composed of both synthetic (metals, ceramics, polymers, etc.) and organic materials (bacteria), or solely made of synthetic materials. The Bionic Leaf has the potential to be implemented in communities, such as urbanized areas to provide clean air as well as providing needed clean energy.
History
In 2009 at MIT, Daniel Nocera's lab first developed the "artificial leaf", a device made from silicon and an anode electrocatalyst for the oxidation of water, capable of splitting water into hydrogen and oxygen gases. In 2012, Nocera came to Harvard and The Silver Lab of Harvard Medical School joined Nocera’s team. Together the teams expanded the existing technology to create the Bionic Leaf. It merged the concept of the artificial leaf with genetically engineered bacteria that feed on the hydrogen and convert CO2 in the air into alcohol fuels or chemicals.
The first version of the teams Bionic Leaf was created in 2015 but the catalyst used was harmful to the bacteria. In 2016, a new catalyst was designed to solve this issue, named the "Bionic Leaf 2.0". Other versions of artificial leaves have been developed by the California Institute of Technology and the Joint Center for Artificial Photosynthesis, the University of Waterloo, and the University of Cambridge.
Mechanics
Photosynthesis
In natural photosynthesis, photosynthetic organisms produce energy-rich organic molecules from water and carbon dioxide by using solar radiation. Therefore, the process of photosynthesis removes carbon dioxide, a greenhouse gas, from the air. Artificial photosynthesis, as performed by the Bionic Leaf, is approximately 10 times more efficient than natural photosynthesis. Using a catalyst, the Bionic Leaf can remove excess carbon dioxide in the air and convert that to useful alcohol fuels, like isopropanol and isobutanol.
The efficiency of the Bionic Leaf's artificial photosynthesis is the result of bypassing obstacles in natural photosynthesis by virtue of its artificiality. In natural systems, there are numerous energy conversion bottlenecks that limit the overall efficiency of photosynthesis. As a result, most plants do not exceed 1% efficiency and even microalgae grown in bioreactors do not exceed 3%. Existing artificial photosynthetic solar-to-fuels cycles may exceed natural efficiencies but cannot complete the cycle via carbon fixation. When the catalysts of the Bionic Leaf are coupled with the bacterium Ralstonia eutropha, this results in a hybrid system capable of carbon dioxide fixation. This system can store more than half of its input energy as products of carbon dioxide fixation. Overall, the hybrid design allows for artificial photosynthesis with efficiencies rivaling that of natural photosynthesis.
Artificial Photosynthesis Systems
The Bionic Leaf is an artificial leaf that interfaces a triple-junction Si wafer with amorphous silicon photovoltaic with hydrogen- and oxygen-evolving catalysts made from a ternary alloy, nickel-molybdenum-zinc (NiMoZn) and a cobalt–phosphate cluster (Co-OEC). The Co-OEC is able to operate in natural water at room temperature. Accordingly, the Bionic Leaf can be immersed in water and when held up to sunlight, it can effect direct solar energy conversion via water-splitting.
The Bionic Leaf, by virtue of the Co-OEC, also exhibits self-assembling and self-healing properties. The Co-OEC self-assembles upon oxidation of an earth metal ion from 2+ to 3+. It also self-heals upon application of a potential, wherein the cluster reforms due to equilibrium between aqueous cobalt and phosphate.
The Bionic Leaf can be used in artificial photosynthetic systems. One such system is a hybrid water-splitting-biosynthetic system that can operate at low driving voltages. The catalyst system of the Bionic Leaf is used in conjunction with bacterium Ralstonia eutropha. The bacterium is grown in contact with the catalysts and then consumes the produced H2 from the water-splitting reaction. After consumption, the bacterium synthesizes biomass and fuels or chemical products from low CO2 concentration in the presence of O2. The usage of the bacterium requires a biocompatible catalyst system that is not toxic to the bacterium and that lowers the overpotential for water splitting. The original catalyst used, the nickel-molybdenum-zinc (NiMoZn) alloy, poisoned the microbes by destroying the bacteria's DNA. Accordingly, this hybrid system uses a cobalt-phosphorus (Co-P) alloy cathode that is resistant to reactive oxygen species. This in return leaves no excess metal and does not form oxygen radicals, leaving the microbes and DNA unharmed. This alloy drives the hydrogen evolution reaction while a cobalt-phosphate (CoPi) anode drives the oxygen evolution reaction. This new catalyst can run up to 16 days at a time when compared to the nickel-molybdenum-zinc (NiMoZn) alloy.
Applications
Agriculture
Early results from Dan Nocera, a researcher at Harvard University, gave insight on how his newly created bionic leaf can be used for fertilizer production. This new bionic leaf uses photovoltaic cells in conjunction with Xanthobacter autotrophicus bacteria to create a plastic called polyhydroxybutyrate (PHB). PHB supplies energy to the bacteria's natural enzymes which then converts nitrogen gas from the air into ammonia. The bionic leaf, can perform this process using renewable electricity, allowing for the sustainable production of ammonia and bio-fertilizers. Currently, the main industrial production of ammonia is performed by what is known as the Haber-Bosch Process, which uses natural gas as the main energy source. The bacteria within the bionic leaf also help to remove carbon dioxide from the environment. The bionic leaf must still pass an environmental impact study in order to determine if this bacteria is safe to release into the wild. Although the bionic leaf currently operates at a mere 25% efficiency, research and development is still with the hopes of improving the process. X. autotrophicus cells act as a living bio-fertilizer due to their ability to directly promote plant growth when applied to organic material. A study was conducted by comparing plants treated with no fertilizer to the same treated with increasing amounts of X. autotrophicus culture. The treated plants root mass and total mass increased by approximately 130% and 100% respectively, compared to that of the untreated control group.
Atmosphere
Carbon dioxide, a greenhouse gas, traps heat in the atmosphere, the bionic leaf can potentially be used to reduce the carbon dioxide within the atmosphere. While the bionic leaf is running mimics photosynthesis by converting the carbon dioxide in air into fuels. The bionic leaf can eliminate 180 grams of carbon dioxide out of 230,000 liters of air for each kilowatt hour of energy it consumes. While removing large amounts of carbon dioxide from the atmosphere not possible yet on a large scale, this technology is useful in areas where carbon dioxide is produced such as power plants. It can also be implemented within urban areas, providing clean air to the area. The technology may also be used on a smaller scale, helping communities produce, harness, and consume the require energy they need.
Bionic Facades
Bionic leaves have been considered as an alternative to vertical greenery systems (VGS), also known as green facades. Like VGS, bionic facades can be implemented in buildings to reduce energy consumption from cooling, absorb solar radiation, and reduce CO2 emissions. Unlike their natural counterpart, bionic facades require less costly maintenance (irrigation, fertilization, pest-control) and can be potentially adjusted to external conditions like the changing of seasons. The general structure of the bionic leaves used for these experiments can be characterized as a photovoltaic (PV) cell or plate resistive heater backed with a ceramic evaporative matrix. An experiment comparing the performance of a PV panel alone versus the bionic leaf panel showed increased electricity production of up to 6.6% due to the evaporative cooling from the matrix. The bionic facade also had a comparable effect on lowering the ambient temperature at the building-to-air interface as a green facade planted with ivy. The cooling effect paired with the electricity output of the bionic facade showed a CO2 emissions reduction that was 25 times greater than the daily average CO2 consumption of the ivy wall.
See also
Artificial Leaf
Bioplastic
Fuel Cell
Metabolic Engineering
Photosynthesis
References
Fuel production
Photosynthesis
Solar energy | Bionic Leaf | [
"Chemistry",
"Biology"
] | 1,815 | [
"Biochemistry",
"Photosynthesis"
] |
60,019,931 | https://en.wikipedia.org/wiki/Openpilot | openpilot is an open-source, semi-automated driving software by comma.ai, Inc. When paired with comma hardware, it replaces advanced driver-assistance systems in various cars, improving over the original system. As of 2023, openpilot supports 250+ car models and has 6000+ users, accumulating over .
openpilot runs on comma 2/3/X hardware, also developed by comma.ai. Packaged as an aftermarket retrofit, it allows users to enhance their existing cars with upgraded computing power, enhanced vision, and regularly updated software. openpilot has been cited to offer a "natural" and human-like driving experience, and reviewed favorably for its ease of use and driver engagement. As of May 2024, openpilot holds the record for the shortest time in a semi-autonomous, coast-to-coast drive across the U.S.
History
comma.ai Inc was founded in September 2015 by George Hotz. The first version of openpilot was revealed a few months later in a Bloomberg article, showing functionality on a 2016 Acura ILX. The video and article instigated a cease and desist letter from the California Department of Motor Vehicles, claiming comma.ai was testing a self-driving car without a license.
openpilot was packaged into a small, shippable device called the "comma one", announced at TechCrunch Disrupt. On October 27, 2016, NHTSA issued a Special Order to comma.ai demanding detailed information about the comma one, to determine if the device complies with legally required Federal Motor Vehicle Safety Standards. comma.ai responded in a tweet from Shenzhen, China, announcing the cancellation of the comma one.
comma.ai open-sourced openpilot a month later, on November 30, 2016, emphasizing its intended use for research, without any warranty.
On January 7, 2020, comma.ai introduced the $999 "comma two" device at CES in Las Vegas. In November 2020, Consumer Reports ranked openpilot above all other advanced driver-assistance systems on the market, including Tesla's Autopilot, Cadillac's Super Cruise and Ford's Co-pilot 360. In particular, openpilot's performance in the areas of driver engagement and ease of use scored better than all other systems evaluated by Consumer Reports.
At comma's 2021 comma_con convention, the company released the "comma three devkit". This model uses two fish eye cameras oriented to the front and a long distance camera oriented to the rear to analyze the car's surroundings.
In January 2023, The Verge found openpilot-based driving-assist technology to be better than that from legacy car manufacturers, delivering more "natural" and human-like driving experience. Nearly 5000 units of openpilot-supported Comma 3 devices were already said to be distributed.
At comma's 2023 COMMA_CON convention, the "comma 3X" was announced as a successor to the comma three devkit at a lower price of $1249. In 2023, the total distance driven by openpilot's 6000+ users was said to have exceeded 90 million miles, an improvement over the 25 million miles figure reported in 2020.
In April 2024, a new semi-autonomous Cannonball run record, involving a drive across the United States from the East Coast to the West Coast, was set using a 2017 Toyota Prius equipped with a comma 3X unit running openpilot. The drive took 43 hours and 18 minutes at 98.4% autonomy, beating the previous record set in a Tesla Model S (97.7% autonomy) by nearly 12 hours.
Comma Hardware
Features
In contrast to traditional autonomous driving solutions where the perception, prediction, and planning units are separate "modules", openpilot adopts a system-level end-to-end design to predict the car's trajectory directly from the camera images. openpilot's end-to-end design is a neural network that is trained by comma.ai using real-world driving data uploaded by openpilot users.
Navigate on openpilot
openpilot 0.9.4 and onwards include "navigate on openpilot", a feature akin to "Full Self-Driving" (FSD) from Tesla, Inc.
Automated lane-centering
openpilot uses machine learning, trained with real-world driving data, to determine the safest path on the road. This improves perception on roads without lane markings vs. lane-centering by tracking current lane lines.
Adaptive cruise control
openpilot maintains a safe following distance from the vehicle ahead. It is capable of driving in stop-and-go traffic with no user intervention. It uses OpenStreetMap's road curvature and speed limit data to allow slowing on sharp turns and setting the vehicle's desired speed to the current speed limit on certain community-maintained forks of the main repository.
Driver monitoring
openpilot recognizes the driver's face; if the driver is distracted, openpilot warns the driver. If the driver is distracted for more than six seconds, openpilot decelerates the vehicle to a stop, and audibly alerts the user.
Assisted lane change
openpilot uses the model to change lanes when the user engages the turn signal: a nudge is optional on the steering wheel to confirm the lane change. openpilot also interacts with the blind spot monitor on certain makes and models to block the lane change in the event a car is detected by the blind spot monitor.
Software updates
openpilot receives over-the-air software updates via WiFi or a cellular phone network, (OTA updates).
Supported cars
At launch, openpilot supported the Honda Civic and the Acura ILX. Support for more vehicles and brands has been added through open-source contribution. As of November 2023, the list of officially supported vehicles contains more than 250 entries, and can be viewed at https://comma.ai/vehicles.
Community
Development is supported by an open-source community using Discord and GitHub.
comma.ai has released tools and guides to help developers port their cars. In addition, they released tools to let users review their drives.
Forks
comma.ai maintains the openpilot codebase and releases, and there is a growing community that maintains various forks of openpilot. These forks consist of experimental features such as stop light detection.
Pre-Autopilot Tesla models have been retrofitted with openpilot through a community fork. Chrysler and Jeep models have also gained support through community contributions.
There are over 6,600 forks of the openpilot GitHub repository.
References
2016 software
Free and open-source software
Self-driving cars
Software using the MIT license | Openpilot | [
"Engineering"
] | 1,416 | [
"Automotive engineering",
"Self-driving cars"
] |
60,020,008 | https://en.wikipedia.org/wiki/Unihertz%20Atom | The Unihertz Atom was released in 2018 as Unihertz's second smartphone model after the Jelly.
Initially launched through a similar kickstarter project
that reached its $50,000 goal in only 60 seconds.
It features a 2.45-inch display, very small by industry standards, and at 108 grams (plus battery) is also very lightweight. It has a dedicated push to talk (PTT) button on its side.
Background
Unihertz Atom was marketed as "the ultimate rugged phone for outdoor adventures".
Unihertz was associated with a previous very small 3G smartphone, the Posh Micro X, which launched in 2015.
Reviews of Jelly and Jelly Pro, the "world's smallest 4G smartphone" have been mixed, but it drew international attention.
Specifications
Software
Hardware
Controversies
There have been accusations of poor battery performance, and network traffic possibly sending personal data to China. Responses claim the network traffic is to speed up apps, and the company has been updating the phone software to improve performance. It is not known whether this is connected to similar widespread problems, but the predecessor Posh Micro X was also criticized for running suspect software fotaprovider by adups, and the Jelly Pro does as well.
References
Smart devices
Android (operating system) devices | Unihertz Atom | [
"Technology"
] | 266 | [
"Home automation",
"Smart devices"
] |
60,021,055 | https://en.wikipedia.org/wiki/NGC%202525 | NGC 2525 is a barred spiral galaxy located in the constellation Puppis. It is located at a distance of about 70 million light years from Earth, which, given its apparent dimensions, means that NGC 2525 is about 60,000 light years across. It was discovered by William Herschel on February 23, 1791.
The galaxy has a bar and two main spiral arms with high surface brightness. HII regions are observed in the arms. The brightest stars of the galaxy have apparent magnitude around 22. Its nucleus is small and bright. In the centre of the galaxy is predicted to lie a supermassive black hole whose age is estimated to be between 1.1 and 44 million years, based on the spiral arm pitch angle.
SN 2018gv
One supernova has been observed in NGC 2525, SN 2018gv. It was discovered on by Kōichi Itagaki on 15 January 2018 at magnitude 16.5, and it was identified spectrographically as a type Ia supernova 10 to 15 days before maximum. The supernova was also observed by ATLAS on 2018 January 14.5 UT at magnitude 18.1. It reached a peak magnitude of 12.8. ESA/Hubble released a video of the supernova in October 2020.
See also
List of NGC objects (2001–3000)
References
External links
NGC 2525 on SIMBAD
Barred spiral galaxies
Puppis
2525
UGCA objects
22721
Astronomical objects discovered in 1791
Discoveries by William Herschel | NGC 2525 | [
"Astronomy"
] | 300 | [
"Puppis",
"Constellations"
] |
60,023,274 | https://en.wikipedia.org/wiki/Plastic%20limit%20theorems | Plastic limit theorems in continuum mechanics provide two bounds that can be used to determine whether material failure is possible by means of plastic deformation for a given external loading scenario. According to the theorems, to find the range within which the true solution must lie, it is necessary to find both a stress field that balances the external forces and a velocity field or flow pattern that corresponds to those stresses. If the upper and lower bounds provided by the velocity field and stress field coincide, the exact value of the collapse load is determined.
Limit theorems
The two plastic limit theorems apply to any elastic-perfectly plastic body or assemblage of bodies.
Lower limit theorem:
If an equilibrium distribution of stress can be found which balances the applied load and nowhere violates the yield criterion, the body (or bodies) will not fail, or will be just at the point of failure.
Upper limit theorem:
The body (or bodies) will collapse if there is any compatible pattern of plastic deformation for which the rate of work done by the external loads exceeds the internal plastic dissipation.
References
Continuum mechanics
Physics theorems | Plastic limit theorems | [
"Physics"
] | 226 | [
"Continuum mechanics",
"Equations of physics",
"Classical mechanics",
"Physics theorems"
] |
60,023,467 | https://en.wikipedia.org/wiki/IP3%20International | IP3 International (International Peace, Power and Prosperity) is a nuclear technology company formed in June 2016. One project involved a plan to transfer nuclear technology from the United States to Saudi Arabia.
History
During the 2016 U.S. presidential campaign of Donald Trump, and subsequently, Trump aides Michael Flynn and Jared Kushner were engaged in promoting IP3 International's plan to transfer nuclear technology from the US to Saudi Arabia, for use in a proposed joint US-Russian project, in possible violation of the Atomic Energy Act. In January 2017, Derek Harvey, a retired Army intelligence officer, former staffer for David Petraeus, and then-staffer of the National Security Council under Michael Flynn, advocated for the IP3 nuclear sales plan. Harvey continued to speak with Michael Flynn "every night" even after Flynn resigned.
In February 2019, United States House Committee on Oversight and Reform chairman Elijah E. Cummings released a report on the matter, based in part upon testimony from whistleblowers within White House. The House Oversight Committee released a second interim staff report and supporting documents in July 2019, highlighting the "gold standard" of nuclear proliferation. It also reported lobbying by Flynn and Barrack and briefings to White House members including President Trump, Jared Kushner, Gary Cohn, Mike Pompeo, and Rick Perry.
Personnel
Notable personnel include:
Keith B. Alexander, cofounder and director, retired Army general, former director of the National Security Agency
Lars Buttler, director, founder of Trion Worlds gaming
James Cartwright, director, retired Marine Corps general, pardoned by President Obama after pleading guilty for leaking classified information
Jack Keane, cofounder and director, retired Army general
Robert McFarlane, cofounder and director, retired Marine Corps officer, pardoned by President George H.W. Bush after pleading guilty for involvement in the Iran-Contra affair
Eric T. Olson, director, retired Navy admiral, former Navy SEAL
Mike Rogers, director, former Republican congressional representative for Michigan
Frances Townsend, director, former Homeland Security Advisor, former Justice Department attorney
Alan Dunn, chief legal officer, twin brother of Congressman Neal Dunn and director of the failed 2018 US Expo Pavilion in Dubai, for which he was sued by the Attorney General of the District of Columbia.
Michael J. Wallace, director, former head of Constellation Energy, member of National Infrastructure Advisory Council, member of Center for Strategic and International Studies
Michael Flynn has described himself as an advisor to IP3, which the company denies. The company does acknowledge that it has a relationship with Flynn and some officials of the company were part of ACU Strategic Partners, but had differences with Russian partnership which was advocated by its managing partner, Alex Copson.
See also
Nuclear energy in Saudi Arabia
References
External links
Nuclear technology companies
Trump administration controversies
Energy in Saudi Arabia | IP3 International | [
"Engineering"
] | 567 | [
"Nuclear technology companies",
"Engineering companies"
] |
60,023,778 | https://en.wikipedia.org/wiki/802.11%20frame%20types | In the IEEE 802.11 wireless LAN protocols (such as Wi-Fi), a MAC frame is constructed of common fields (which are present in all types of frames) and specific fields (present in certain cases, depending on the type and subtype specified in the first octet of the frame).
The very first two octets transmitted by a station are the Frame Control. The first three subfields within the frame control and the last field (FCS) are always present in all types of 802.11 frames. These three subfields consist of two bits Protocol Version subfield, two bits Type subfield, and four bits Subtype subfield.
Frame control
The first three fields (Protocol Version, Type and Subtype) in the Frame Control field are always present. The fields, in their order of appearance in transmission, are:
Protocol Version
Type
Subtype
To-DS
From-DS
More-Fragments
Retry
Power Management
More Data
Protected frame
+HTC/order
Protocol version subfield
The two-bit protocol version subfield is set to 0 for WLAN (PV0) and 1 for IEEE 802.11ah (PV1). The revision level is incremented only when there is a fundamental incompatibility between two versions of the standard. PV1 description is incorporated in the latest 802.11-2020 standard.
Types and subtypes
Action frames
Action frames extend management frames to control a certain action. Some of the action categories are QoS, Block Ack, Public, Radio Measurement, Fast BSS Transition, Mesh Peering Management, etc. These frames are sent by a station when it needs to tell its peer for a certain action to be taken.
For example, a station can tell another station to set up a block acknowledgement by sending an ADDBA Request action frame. The other station would then respond with an ADDBA Response action frame.
Wi-Fi Neighbor Awareness Networking (NAN), also known as Wi-Fi Aware, service discovery frames are NAN-specific public action frames. They are used in Remote ID for example.
ToDS and FromDS
ToDS is one bit in length and set to 1 if destined to Distribution System, while FromDS is a one-bit length that is set to 1 if originated from Distribution System.
Retry
Set to 1 if the Data or Management frame is part retransmission of the earlier frame. This bit is reused for different purpose in Control frame.
Protected frame
Set to 1 if the Management Frame is protected by encryption as described in IEEE_802.11w-2009.
+HTC/order
It is one bit in length and is used for two purposes:
It is set to 1 in a non-QoS data frame transmitted by a non-QoS WLAN station to indicate the frame being transmitted is using Strictly-Ordered service class (this use is obsolete and will be removed from the future 802.11 Standard).
It is set to 1 in a QoS data or management frame transmitting at HT or higher rate to indicate that the frame contains HT Control field (see above)
References
Wi-Fi
Networking standards | 802.11 frame types | [
"Technology",
"Engineering"
] | 632 | [
"Computer standards",
"Wireless networking",
"Wi-Fi",
"Computer networks engineering",
"Networking standards"
] |
60,023,903 | https://en.wikipedia.org/wiki/Neukom%20Institute%20for%20Computational%20Science | The Neukom Institute for Computational Science is a collection of offices and laboratory facilities at Dartmouth College in Hanover, New Hampshire. The institute was funded by a donation from Bill Neukom in 2004, then Dartmouth's largest gift for an academic program. The institute provides programs for undergraduates and graduate students as well as encouraging public engagement with computer science through programs such as the Neukom Institute Literary Arts Awards.
Literary Arts Awards
The Neukom Institute Literary Arts Awards are presented to celebrate new works of speculative fiction. The three categories are: Speculative Fiction, Debut Speculative Fiction and Playwriting.
Speculative Fiction
This award is for any work of speculative fiction published in the last two and a half years or that is about to be published.
Recipients
The inaugural award in 2018 was to Central Station by Lavie Tidhar and On the Edge of Gone by Corinne Duyvis.
2019: Theory of Bastards by Audrey Schulman
Debut Speculative Fiction
This award is for an author's first work of speculative fiction.
Recipients
The inaugural award in 2018 was presented to Best Worst American by Juan Martinez.
Playwriting
This award is for a full-length play addressing the question "What does it mean to be a human in a computerized world?"
Recipients
The inaugural award in 2018 was presented to Choices People Make by Jessica Andrewartha.
References
External links
Neukom Institute homepage
Neukom Institute Literary Arts Awards home page
Dartmouth College facilities
Computational science
American literary awards
American theater awards
Awards established in 2018 | Neukom Institute for Computational Science | [
"Mathematics"
] | 300 | [
"Computational science",
"Applied mathematics"
] |
60,024,393 | https://en.wikipedia.org/wiki/NGC%204065%20Group | The NGC 4065 Group is a group of galaxies located about in the constellation Coma Berenices. The group's brightest member is NGC 4065 and located in the Coma Supercluster.
The group is dominated by mostly elliptical galaxies with only 15 to 31 percent of the members being spiral galaxies.
X-ray emission
The NGC 4065 Group exhibits bimodal X-ray emission with one peak on the galaxies NGC 4061 and NGC 4065 and the other on NGC 4066.
Structure
The NGC 4065 Group appears to consist of two subgroups known as UZC-CG 156 and UZC-CG 157 which are indistinguishable by velocity.
However, White et al. suggests that the group contains three subgroups with subgroups A and C being centered on NGC 4065 and NGC 4095 respectively, and subgroup B which consists of the galaxies NGC 4086 and NGC 4090.
At the center of the group lie the elliptical galaxies NGC 4061 and NGC 4065.
Nearby groups
The NGC 4065 Group is located near the Leo Cluster and is part of a bridge of galaxies that connects the Leo Cluster to the Coma Cluster.
See also
NGC 4065
Leo Cluster
Coma Cluster
List of Galaxy Groups
References
External links
Finding Chart for the NGC 4065 Group
Coma Supercluster
Coma Berenices
Galaxy clusters | NGC 4065 Group | [
"Astronomy"
] | 275 | [
"Coma Berenices",
"Galaxy clusters",
"Astronomical objects",
"Constellations"
] |
63,577,875 | https://en.wikipedia.org/wiki/Bernhard%20Cinader%20Award | The Bernhard Cinader Award is awarded annually by the Canadian Society for Immunology (CSI). It is presented to an immunologist who is an exceptional researcher working in Canada, a full member of CSI and who has an additional activity in which they excel.
This award was inaugurated at the first meeting of the CSI in 1987 and is named in honor of Dr. Bernhard "Hardy" Cinader. The recipient presents the keynote lecture at the annual CSI meeting.
Recipients
The Bernhard Cinader award lectureship is given to a Canadian scientist who exemplifies distinguished scientific leadership and accomplishments in Immunology.
References
Biomedical awards
Cinader award | Bernhard Cinader Award | [
"Biology"
] | 134 | [
"Immunology"
] |
63,578,074 | https://en.wikipedia.org/wiki/Costruzioni%20Motori%20Diesel%20S.p.A. | The () or more simply CMD is an Italian company that designs, develops, builds and markets marine engines, with its brand FNM Marine.
History
The Company was founded in 1971, under the name Fratelli Negri Macchine Diesel Sud (FNM), on the initiative of the Negri brothers. Initially, the activity focused on the revision of earthmoving machines, then expanding in the mid-70s, in the installation of diesel engines on used cars. Furthermore, towards the end of the decade, collaboration with FIAT began, which still represents an important slice of the company's business. In 2013, indeed, the company signed an agreement to produce engine heads for Maserati and Jeep.
In 1980, the GD 178 AT 1.3 supercharged diesel engine, entirely designed and built by FNM, was presented at the Turin International Motor Show.
In 1991, CMD Costruzioni Motori Diesel was set up, which would acquire the entire FNM business branch and related know-how. In the 1990s, CMD inaugurated the Atella 1 plant, expanding its business producing and selling marine diesel engines. In 1996, FNM 1.4-liter diesel engines began to be installed in passenger cars built by India's Premier Automobiles Limited, in two Fiat-derived models called the Premier 137D and 1.38D.
In the 2000s the company opened two new production plants, Atella 2 in 2004 and Morra De Sanctis in 2005. In 2017 67% of the share capital was held by the Chinese Loncin Holdings group, while the remaining 33% was in Italian hands. The official dealer is AS Labruna which is based in Monopoli, Apulia.
Engines
The company builds various types of marine inboard motor including hybrids.
Awards
Premio ADI (Association for Industrial Design) 2019, at the 59° Salone Nautico di Genova thanks to the engine Blue Hybrid System.
See also
AS Labruna
Inboard motor
Fiat Chrysler Automobiles
References
Propulsion
Marine engineering
Italian brands
Companies based in Campania
Companies based in Basilicata
Engine manufacturers of Italy | Costruzioni Motori Diesel S.p.A. | [
"Engineering"
] | 435 | [
"Marine engineering"
] |
63,579,017 | https://en.wikipedia.org/wiki/Jack%20Ma%20Foundation | The Jack Ma Foundation (JMF, established 2014) is the philanthropic foundation of Chinese businessman Jack Ma.
History
In September 2018, Ma announced that he would retire from the company he founded and the source of his wealth, internet merchandiser Alibaba, in order to pursue educational work, philanthropy, and environmental causes.
In 2019 the JMF started the Netpreneur Initiative that grants ten prizes of one million dollars each to ten African entrepreneurs per year and launched a fund with $14.6 million to develop education in Tibet.
In 2020, JMF was announced as one of the alliance partners of Prince William's Earthshot Prize to find solutions to environmental issues.
Coronavirus
In March 2020, in response to the coronavirus pandemic, the Jack Ma Foundation announced its intention to donate a total 500,000 testing kits and 1 million masks to the United States, stating "we join hands with Americans in these difficult times". The Foundation, along with the Alibaba Group, has also donated similar materials to Iran, Italy, Spain, Belgium, Japan and South Korea. He also announced a donation of 1.1 million tests, 6 million masks, and 60,000 protective suits to all African countries to combat the pandemic. For instance in Nigeria a senior health official, Abdulaziz Abdullahi, said that the country had received 100,000 face masks, 1,000 protective gowns and 20,000 test kits.
On 18 March 2020, the JMF published Handbook of COVID-19 Prevention and Treatment, a detailed 68-page book edited by Tingbo Liang that documents the clinical experience obtained at the First Affiliated Hospital of the Zhejiang University School of Medicine in the fight against the coronavirus pandemic.
The BBC called Ma's efforts to send medical equipment to over 150 countries "unrivaled". While Jack Dorsey of Twitter has pledged more money, Ma's shipments of vital supplies might sometimes be more welcome than cash. Beneficiaries include the U.S., Russia, Israel, and Iran; as of April 2020, Ma has declined to donate to any countries such as Honduras and Haiti that have diplomatic ties with Taiwan. Chinese ambassadors are often present at ceremonial handovers of Ma's supplies to beneficiary countries. Ma's shipments appear to have gone smoothly, with the exceptions of Cuba and Eritrea; in contrast, shipments to several countries from the Chinese government have been criticized for being faulty or being too low-quality to use. Following U.S. State Department gratitude over Taiwan's shipment of 2 million masks, the Chinese Foreign Ministry tweeted in April 2020, "Wonder if @StateDept has any comment on Jack Ma's donation of 1 million masks and 500k testing kits as well as Chinese companies' and provinces' assistance?" Chinese media at one point in April 2020 mentioned Ma almost as often as it mentioned Chinese Communist Party leader, Xi Jinping. While Ma is a member of the Chinese Communist Party, some analysts nevertheless believe that the Chinese government may view Ma's personal foreign and domestic popularity as a mixed blessing.
External links
Homepage
References
Jack Ma
Biomedical research foundations
Organizations established in 2018
2018 establishments in China
Organizations associated with the COVID-19 pandemic | Jack Ma Foundation | [
"Engineering",
"Biology"
] | 665 | [
"Biotechnology organizations",
"Biomedical research foundations"
] |
63,579,110 | https://en.wikipedia.org/wiki/Ndumu%20virus | Ndumu virus is an RNA virus in the genus Alphavirus. It was first isolated in 1961 from culicine mosquitoes collected in northern Natal, Union of South Africa.
References
Alphaviruses | Ndumu virus | [
"Biology"
] | 42 | [
"Virus stubs",
"Viruses"
] |
63,579,202 | https://en.wikipedia.org/wiki/Ring%20lemma | In the geometry of circle packings in the Euclidean plane, the ring lemma gives a lower bound on the sizes of adjacent circles in a circle packing.
Statement
The lemma states: Let be any integer greater than or equal to three. Suppose that the unit circle is surrounded by a ring of interior-disjoint circles, all tangent to it, with consecutive circles in the ring tangent to each other. Then the minimum radius of any circle in the ring is at least the unit fraction
where is the th Fibonacci number.
The sequence of minimum radii, from , begins
Generalizations to three-dimensional space are also known.
Construction
An infinite sequence of circles can be constructed, containing rings for each that exactly meet the bound of the ring lemma, showing that it is tight. The construction allows halfplanes to be considered as degenerate circles with infinite radius, and includes additional tangencies between the circles beyond those required in the statement of the lemma. It begins by sandwiching the unit circle between two parallel halfplanes; in the geometry of circles, these are considered to be tangent to each other at the point at infinity. Each successive circle after these first two is tangent to the central unit circle and to the two most recently added circles; see the illustration for the first six circles (including the two halfplanes) constructed in this way. The first circles of this construction form a ring, whose minimum radius can be calculated by Descartes' theorem to be the same as the radius specified in the ring lemma. This construction can be perturbed to a ring of finite circles, without additional tangencies, whose minimum radius is arbitrarily close to this bound.
History
A version of the ring lemma with a weaker bound was first proven by Burton Rodin and Dennis Sullivan as part of their proof of William Thurston's conjecture that circle packings can be used to approximate conformal maps. Lowell Hansen gave a recurrence relation for the tightest possible lower bound, and Dov Aharonov found a closed-form expression for the same bound.
Applications
Beyond its original application to conformal mapping, the circle packing theorem and the ring lemma play key roles in a proof by Keszegh, Pach, and Pálvölgyi that planar graphs of bounded degree can be drawn with bounded slope number.
References
Circle packing
Lemmas
Fibonacci numbers
Geometric inequalities | Ring lemma | [
"Mathematics"
] | 498 | [
"Geometry problems",
"Mathematical theorems",
"Packing problems",
"Recurrence relations",
"Fibonacci numbers",
"Golden ratio",
"Circle packing",
"Mathematical relations",
"Geometric inequalities",
"Inequalities (mathematics)",
"Theorems in geometry",
"Mathematical problems",
"Lemmas"
] |
63,579,965 | https://en.wikipedia.org/wiki/Chick%20syncytial%20virus | The chick syncytial virus is a virus in the genus Gammaretrovirus.
References
Gammaretroviruses | Chick syncytial virus | [
"Biology"
] | 25 | [
"Virus stubs",
"Viruses"
] |
63,580,004 | https://en.wikipedia.org/wiki/ISO/IEC%2027019 | ISO/IEC TR 27019 is a security standard, part of the ISO/IEC 27000 family of standards. It was published by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC) under the joint ISO and IEC subcommittee, ISO/IEC JTC 1/SC 27.
It is based on ISO/IEC 27002, but it is applied for energy management (to control generation, transmission, storage and distribution of electric power) and for the control of associated supporting processes. It is not applied to the process control of nuclear facilities and it is not applied to telecommunication systems and components used in the process control environment. ISO/IEC TR 27019 first version was published in July 2013. and its latest version was published on November 27 of 2017.
Versions
That standard has two versions:
ISO/IEC 27019:2013
ISO/IEC 27019:2017
References
External links
ISO Website
Computer security standards
Information assurance standards
27019 | ISO/IEC 27019 | [
"Technology",
"Engineering"
] | 194 | [
"Computer security standards",
"Computer standards",
"Information assurance standards",
"Cybersecurity engineering"
] |
63,581,392 | https://en.wikipedia.org/wiki/Xiaomi%20Mi%20A2%20Lite | The Xiaomi Mi A2 Lite is a budget smartphone developed by Xiaomi, a global version of the company's Redmi 6 Pro, co-developed by Google as part of its Android One project.
Specifications
Hardware
The phone features a 5.84 inches Full HD+ (1080 x 2280 pixels resolution) 432ppi pixel density display, semi-metal body. It is powered by a Qualcomm Snapdragon 625 processor along with Adreno 506 GPU and has a 2.0 micro USB connector. It has a dual rear camera (Primary camera is 12MP sensor of 1.25μm pixel size and f2.2 aperture and Secondary has 5MP sensor of 1.12μm pixel size with f2.2 aperture). The front camera is 5MP sensor of f2.0 aperture. The battery is of 4000 mAh.
Software
The Xiaomi Mi A2 Lite is part of the Android One program, where software updates are provided directly from Google.
It is preinstalled with Android 8.1.0 "Oreo" out of the box, and can be upgraded to Android 10.
Being a part of Android One program, Mi A2 Lite provides a Stock Android experience and UI which is very close to those of Google Pixel UI.
Release
The Xiaomi Mi A2 Lite is a re-branded Xiaomi Redmi 6 Pro phone. It was released in July 2018.
The company discontinued the smartphone's sale in favor of the successors Redmi 7 and Redmi Note 7.
References
Android (operating system) devices
Mobile phones introduced in 2018
Phablets
Mobile phones with multiple rear cameras
Xiaomi smartphones
Mobile phones with infrared transmitter
Discontinued smartphones | Xiaomi Mi A2 Lite | [
"Technology"
] | 351 | [
"Crossover devices",
"Phablets"
] |
63,583,623 | https://en.wikipedia.org/wiki/Greater%20Dublin%20Area%20Cycle%20Network | The Greater Dublin Area Cycle Network is a proposed cycle network for the Greater Dublin Area. The plan was launched in 2013.
A target, endorsed by the Irish government, proposed that the number of people commuting into Dublin would reach "75,000 each morning by 2021", representing a "three-fold increase in cycling over 2011 levels". A significant part of the proposed plan, as published in 2013, expected that the Greater Dublin Area's cycle network would increase "five fold" from 500 km in length to over 2,800 km by 2020. The planned targets were not met.
In August 2018, 78 companies and third-level education institutions called on the government to build a network of segregated cycle routes in Dublin. This call was reiterated by the National Children's Hospital and St. James's Hospital in 2019.
The letter from St James's Hospital to the Minister for Transport cited worrying levels of air pollution, adding,
As of mid-2021, the National Transport Authority (NTA) website noted that "the NTA [..was then..] in the process of updating the GDA Cycle Network Plan" and that it planned to publish this update "later in 2021".
References
Cycling infrastructure
Cycling in Ireland
Transport infrastructure
Transport in Dublin (city)
Dublin
Transport in County Kildare
Transport in County Meath
Transport in County Wicklow | Greater Dublin Area Cycle Network | [
"Physics"
] | 277 | [
"Physical systems",
"Transport",
"Transport infrastructure"
] |
63,583,636 | https://en.wikipedia.org/wiki/MIoTy | mioty (stylized as MIoTy) is a low-power wide-area network (LPWAN) protocol. It is using telegram splitting, a standardized LPWAN technology in the license-free spectrum. This technology splits a data telegram into multiple sub packets and sends them after applying error correcting codes, in a partly predefined time and frequency pattern. This makes a transmission robust to interferences and packet collisions. It is standardised in the TS 103 357 ETSI. Its uplink operates at the 868 MHz band, license free in Europe, and 916MHz band in North America. It requires a bandwidth of 200 kHz for two channels (e.g. up- and downlink).
Technology attributes
Long range: The operating range of LPWAN technology varies from a few kilometers in urban areas to over 10 km in rural settings. It can also enable effective data communication in previously infeasible indoor and underground locations.
Low power: Optimized for power consumption, LPWAN transceivers can run on small, inexpensive batteries for up to 20 years.
Telegram splitting: (or TSMA, telegram splitting multiple access) Splits the packets of data under transport in small sub-packets at the sensor level. The small packets getting then transmitted over variable frequency and time.
More than a million packets a day.
Serving moving clients. It can serve data from clients moving at up to 120 km/h.
Applications
It is intended to be used for monitoring devices in large areas.
See also
Internet of Things
References
Wide area networks
Wireless networking | MIoTy | [
"Technology",
"Engineering"
] | 319 | [
"Wireless networking",
"Computer networks engineering"
] |
63,584,718 | https://en.wikipedia.org/wiki/Richards%27%20theorem | Richards' theorem is a mathematical result due to Paul I. Richards in 1947. The theorem states that for,
if is a positive-real function (PRF) then is a PRF for all real, positive values of .
The theorem has applications in electrical network synthesis. The PRF property of an impedance function determines whether or not a passive network can be realised having that impedance. Richards' theorem led to a new method of realising such networks in the 1940s.
Proof
where is a PRF, is a positive real constant, and is the complex frequency variable, can be written as,
where,
Since is PRF then
is also PRF. The zeroes of this function are the poles of . Since a PRF can have no zeroes in the right-half s-plane, then can have no poles in the right-half s-plane and hence is analytic in the right-half s-plane.
Let
Then the magnitude of is given by,
Since the PRF condition requires that for all then for all . The maximum magnitude of occurs on the axis because is analytic in the right-half s-plane. Thus for .
Let , then the real part of is given by,
Because for then for and consequently must be a PRF.
Richards' theorem can also be derived from Schwarz's lemma.
Uses
The theorem was introduced by Paul I. Richards as part of his investigation into the properties of PRFs. The term PRF was coined by Otto Brune who proved that the PRF property was a necessary and sufficient condition for a function to be realisable as a passive electrical network, an important result in network synthesis. Richards gave the theorem in his 1947 paper in the reduced form,
that is, the special case where
The theorem (with the more general casse of being able to take on any value) formed the basis of the network synthesis technique presented by Raoul Bott and Richard Duffin in 1949. In the Bott-Duffin synthesis, represents the electrical network to be synthesised and is another (unknown) network incorporated within it ( is unitless, but has units of impedance and has units of admittance). Making the subject gives
Since is merely a positive real number, can be synthesised as a new network proportional to in parallel with a capacitor all in series with a network proportional to the inverse of in parallel with an inductor. By a suitable choice for the value of , a resonant circuit can be extracted from leaving a function two degrees lower than . The whole process can then be applied iteratively to until the degree of the function is reduced to something that can be realised directly.
The advantage of the Bott-Duffin synthesis is that, unlike other methods, it is able to synthesise any PRF. Other methods have limitations such as only being able to deal with two kinds of element in any single network. Its major disadvantage is that it does not result in the minimal number of elements in a network. The number of elements grows exponentially with each iteration. After the first iteration there are two and associated elements, after the second, there are four and so on.
Hubbard notes that Bott and Duffin appeared not to know the relationship of Richards' theorem to Schwarz's lemma and offers it as his own discovery, but it was certainly known to Richards who used it in his own proof of the theorem.
References
Bibliography
Bott, Raoul; Duffin, Richard, "Impedance synthesis without use of transformers", Journal of Applied Physics, vol. 20, iss. 8, p. 816, August 1949.
Cauer, Emil; Mathis, Wolfgang; Pauli, Rainer, "Life and Work of Wilhelm Cauer (1900 – 1945)", Proceedings of the Fourteenth International Symposium of Mathematical Theory of Networks and Systems (MTNS2000), Perpignan, June, 2000.
Hubbard, John H., "The Bott-Duffin synthesis of electrical circuits", pp. 33–40 in, Kotiuga, P. Robert (ed), A Celebration of the Mathematical Legacy of Raoul Bott, American Mathematical Society, 2010 .
Hughes, Timothy H.; Morelli, Alessandro; Smith, Malcolm C., "Electrical network synthesis: A survey of recent work", pp. 281–293 in, Tempo, R.; Yurkovich, S.; Misra, P. (eds), Emerging Applications of Control and Systems Theory, Springer, 2018 .
Richards, Paul I., "A special class of functions with positive real part in a half-plane", Duke Mathematical Journal, vol. 14, no. 3, 777–786, 1947.
Wing, Omar, Classical Circuit Theory, Springer, 2008 .
Theorems in complex analysis
Electronic engineering
Network synthesis
Circuit theorems | Richards' theorem | [
"Physics",
"Mathematics",
"Technology",
"Engineering"
] | 983 | [
"Theorems in mathematical analysis",
"Equations of physics",
"Computer engineering",
"Theorems in complex analysis",
"Electronic engineering",
"Circuit theorems",
"Electrical engineering",
"Physics theorems"
] |
63,584,864 | https://en.wikipedia.org/wiki/Copulas%20in%20signal%20processing | A copula is a mathematical function that provides a relationship between marginal distributions of random variables and their joint distributions. Copulas are important because it represents a dependence structure without using marginal distributions. Copulas have been widely used in the field of finance, but their use in signal processing is relatively new. Copulas have been employed in the field of wireless communication for classifying radar signals, change detection in remote sensing applications, and EEG signal processing in medicine. In this article, a short introduction to copulas is presented, followed by a mathematical derivation to obtain copula density functions, and then a section with a list of copula density functions with applications in signal processing.
Introduction
Using Sklar's theorem, a copula can be described as a cumulative distribution function (CDF) on a unit-space with uniform marginal distributions on the interval (0, 1). The CDF of a random variable X is the probability that X will take a value less than or equal to x when evaluated at x itself. A copula can represent a dependence structure without using marginal distributions. Therefore, it is simple to transform the uniformly distributed variables of copula (u, v, and so on) into the marginal variables (x, y, and so on) by the inverse marginal cumulative distribution function. Using the chain rule, copula distribution function can be partially differentiated with respect to the uniformly distributed variables of copula, and it is possible to express the multivariate probability density function (PDF) as a product of a multivariate copula density function and marginal PDF''s. The mathematics for converting a copula distribution function into a copula density function is shown for a bivariate case, and a family of copulas used in signal processing are listed in a TABLE 1.
Mathematical derivation
For any two random variables X and Y, the continuous joint probability distribution function can be written as
where and
are the marginal cumulative distribution functions of the random variables X and Y, respectively.
then the copula distribution function can be defined using Sklar's theorem as:
,
where and are marginal distribution functions, joint and .
We start by using the relationship between joint probability density function (PDF) and joint cumulative distribution function (CDF) and its partial derivatives.
(Equation 1)
where is the copula density function, and are the marginal probability density functions of X and Y, respectively. It is important understand that there are four elements in the equation 1, and if three of the four are know, the fourth element can me calculated. For example, equation 1 may be used
when joint probability density function between two random variables is known, the copula density function is known, and one of the two marginal functions are known, then, the other marginal function can be calculated, or
when the two marginal functions and the copula density function are known, then the joint probability density function between the two random variables can be calculated, or
when the two marginal functions and the joint probability density function between the two random variables are known, then the copula density function can be calculated.
Summary table
The use of copula in signal processing is fairly new compared to finance. Here, a family of new bivariate copula density functions are listed with importance in the area of signal processing. Here, and are marginal distributions functions and and are marginal density functions
TABLE 1: Copula density function of a family of copulas used in signal processing.
References
Signal processing | Copulas in signal processing | [
"Technology",
"Engineering"
] | 703 | [
"Telecommunications engineering",
"Computer engineering",
"Signal processing"
] |
63,585,551 | https://en.wikipedia.org/wiki/NGC%203007 | NGC 3007 is an edge-on, magnitude 13.4, lenticular galaxy in the constellation of Sextans, discovered by French astronomer Édouard Stephan on March 16, 1885. It is about 115 thousand light years across, and with a recessional velocity of 6,520 kilometers per second, is at a distance of over 300 million light-years from the Sun.
See also
List of NGC objects (3001–4000)
References
Lenticular galaxies
Sextans
3007
-01-25-038
IRAS 09452-0612
028150
Astronomical objects discovered in 1885
Discoveries by Édouard Stephan | NGC 3007 | [
"Astronomy"
] | 126 | [
"Sextans",
"Constellations"
] |
63,586,322 | https://en.wikipedia.org/wiki/Marine%20Chemistry%20%28journal%29 | Marine Chemistry is an international peer-reviewed scientific journal for publications in the field of chemistry in the marine environment. The journal is currently published by Elsevier. Its editor-in-chief is T.S. Bianchi. According to the Journal Citation Reports, Marine Chemistry has a 2020 impact factor of 3.807.
References
External links
Chemistry journals
Chemical oceanography
English-language journals
Monthly journals | Marine Chemistry (journal) | [
"Chemistry"
] | 82 | [
"Chemical oceanography",
"Geochemistry stubs"
] |
63,588,192 | https://en.wikipedia.org/wiki/Andreaea%20rupestris | Andreaea rupestris is a species of moss in the class Andreaeopsida, are commonly referred to as the "lantern mosses" due to the appearance of their dehisced sporangia. It is typically found on smooth, acidic, exposed rock in the Northern hemisphere. It exhibits the common features of the genus Andreaea such as being acrocarpous, having dark pigmentation, lacking a seta, and bearing 4 lines of dehiscence in its mature sporangia, but can be further identified upon careful examination of its gametophytic leaves which have an ovate base to a more blunt apex compared to other similar species.
Taxonomy and classification
Andreaea rupestris is in the genus Andreaea, which has around 100 different species.
It may be difficult to differentiate A. rupestris from some other species in its genus as it does bear some similar characteristics to other species. Some species which may be mistaken for A. rupestris are:
A. rothii, which has a similar habitat to A. rupestris but its leaves are nerved, and they are falcate-secund in both moist and dry conditions (A. rupestris is only falcate-secund in moist conditions).
A. mutabilis, which has a similar appearance but has a yellow leaf bases, which are more widely spread apart.
A. alpestris and A. sinuosa, which can only be differentiated from A. rupestris using a microscope.
A. megistospora, which has a similar habitat to A. rupestris and can only be differentiated by the size of its spores, and its nerved leaves.
Description
The appearance of Andreaea rupestris is dark in colour, varying from dark red/brown/green to black depending on its life stage. It grows in patches of dense, cushion-like tufts up to 2–3 cm high and has imbricate leaves in dry conditions. In moist conditions, the leaves may be falcate-secund (curved to one side) yet this does not always hold true. Unlike some other mosses, A. rupestris have biseriate rhizoids which aid in attaching the gametophyte to substrate.
Gametophyte
The gametophyte leaves have an ovate base tapering to a blunt to acute apex and are less than 1mm in length. They lack a costa and may have papillae on the dorsal side, particularly on the upper leaves of the stem. The leaves are bordered by shorter, rhombic marginal cells and their laminal cells have thickened cell walls. Their perichaetial leaves are typically larger than their stem leaves. In contrast to most bryophytes which have a filamentous protonemal stage, Andreaea rupestris have thalloid protonema that give rise to the leafy shoot of the gametophyte.
Sporophyte
As characterized by the Andreaeopsida, Andreaea rupestris have small sporophytes which lack both an operculum and a seta. Instead of a seta, they have a pseudopodium derived from gametophytic tissue attached to the sporangium, extending from the perichaetium attached by a structure called the foot. Once fully mature, the sporangium will open along 4 vertical lines of dehiscence to release the spores inside. The sporangium is hygroscopic as it will dehisce in dry conditions to release spores from the gaps, and will close back up in moist conditions. The spores are red-brown in colour, usually larger than 20 μm in diameter, and lack elaters.
Habitat and distribution
Andreaea rupestris are typically found in cooler climates on surfaces or fissures of dry, siliceous, exposed rock such as granite. While they can also grow in neutral to mildly basic conditions, they are usually found on acidic rocks and cliff walls. They can be found from sea level to high elevations, but are more commonly associated with higher altitudes. Compared to other species in their genus, they can withstand a wider variety of moisture levels and are better at surviving in drier conditions. They have been found to grow with other species of their genus such as Andreaea nivalis , A. blyttii, A. rigida, A. crassinervia, A. rothii ssp. rothii, A. rothii ssp. jalcata, A. alpina, and A. obovata.
They are primarily distributed around the Northern hemisphere in North America, Europe, and Asia. More specifically, they have been confirmed in Canada, the United States, Norway, Britain, Ireland, Kazakhstan, Korea, China, Japan, Central America, New Zealand, Antarctica and more recently in 2018, Greece.
Life cycle and reproduction
The sporophyte and gametophyte represent two generations of A. rupestris, also known as the alternation of heteromorphic generations. The gametophyte stage starts with the haploid spore, which then germinates into a thalloid protonema. The protonema then gives rise to the leafy gametophyte which houses the male and female organs also known as the antheridia and archegonia, respectively.
Andreaea rupestris are autoicous, meaning that their male and female organs exist on separate branches within the same gametophyte. The close proximity of the antheridia and archegonia helps facilitate fertilization. The antheridia contain sperm that travel down the neck of an archegonium, which houses the egg, to fertilize it. When the egg is fertilized and becomes a diploid zygote, it then develops into the diploid sporangium. Note that the sporangium is attached to a haploid pseudopodium that was derived from gametophytic tissue. Through the process of meiosis, haploid spores are produced and released through the gaps of the dehisced sporangium.
Conservation
According to the BC Conservation Data Centre, this species is deemed "demonstrably widespread, abundant and secure" globally. In British Columbia, it is labelled as "at the least risk of being lost".
References
Andreaeaceae
Lithophytes
Taxa named by Johann Hedwig
Plants described in 1801 | Andreaea rupestris | [
"Biology"
] | 1,340 | [
"Lithophytes",
"Plants"
] |
67,885,296 | https://en.wikipedia.org/wiki/Quran%20code | The term Quran code (also known as Code 19) refers to the claim that the Quranic text contains a hidden mathematically complex code. Advocates believe that the code represents a mathematical proof of the divine authorship of the Quran, however this claim has not been validated by any independent mathematical or scientific institute. Proponents of the Quran code claim that the code is based on statistical procedures. The most notable proponent is Rashad Khalifa who, in 1969, described the Quranic initials through enumerations and distributions, and in 1974, claimed to have discovered a mathematical code hidden in the Quran, a code based around the number 19.
History
In 1969, Rashad Khalifa, an Egyptian-American biochemist, began analyzing the separated letters of the Quran (also called Quranic initials or Muqattaʿat), and the Quran to examine certain sequences of numbers. In 1973 he published the book Miracle of the Quran: Significance of the Mysterious Alphabets, in which he describes the Quranic initials through enumerations and distributions.
In 1974, Khalifa claimed to have discovered a mathematical code hidden in the Quran, a code based around the number 19. He wrote the book The Computer Speaks: God's Message to the World, in which he thematizes this Quran code. He relies on Surah 74, verse 30 to prove the significance of the number: "Over it is nineteen,".
Proponents of the code include United Submitters International (an association initiated by Rashad Khalifa) as well as some Quranists and traditional Muslims.
Example
Believers in Quran Code often use certain word counts, checksums and cross sums to legitimize the code.
Edip Yüksel, a Turkish Quranistic author and colleague of Rashad Khalifa, makes the following claims in his book Nineteen: God's Signature in Nature and Scripture:
The Bismillah (bismi ʾllāhi ʾr-raḥmāni ʾr-raḥīm), the Quranic opening formula, which, with one exception, is at the beginning of every Surah of the Quran, consists of exactly 19 letters.
The first word of the Bismillah, Ism (name), without contraction, occurs 19 times in the Quran (19×1). [Also no plural forms, or those with pronoun endings]
The second word of the Bismillah, Allah (God), occurs 2698 times (19×142).
The third word of the Bismillah, Rahman (Gracious), occurs 57 times (19×3).
The fourth word of the Bismillah, Rahim (Merciful), occurs 114 times (19×6).
The multiplication factors of the words of the Bismillah (1+142+3+6) give 152 (19×8).
The Quran consists of 114 chapters (19×6).
The total number of verses in the Quran including all unnumbered Bismillahs is 6346 (19×334). The cross sum of 6346 is 19.
The Bismillah appears 114 times (despite its absence in chapter 9, it appears twice in chapter 27); 114 is 19×6.
From the missing Bismillah in chapter 9 to the additional Bismillah in chapter 27, there are exactly 19 chapters.
The occurrence of the additional Bismillah is in Surah 27:30. Adding this chapter number and the verse number gives 57 (19×3).
The separated letters in the Quran
The Quran consists of 114 Surahs, of which a total of 29 Surahs are provided with separated letters, Muqattaʿat or also called Quranic initials. These are listed in the following table:
Rashad Khalifa wrote in his book, The Computer Speaks: God's Message to the World, that the separated letters of the Quran, or Quranic Initials, held the key to the Quran Code. By analyzing the Quran's 29 initialized Surahs statistically, Khalifa claimed to reveal complex mathematical patterns centered around the number 19.
Quranic Gematria
Each Arabic letter can be assigned a specific numerical value, also called gematria:
Abdullah Arik, a Quranistic author, uses this method in his book Beyond Probability: God's Message in Mathematics to analyze the Basmala gematrically. He gives various numerological arguments relying on these values to bolster his arguments.
Reception in the Western world
Khalifa's research received little attention in the Western world. In 1980, Martin Gardner mentioned Khalifa's work in Scientific American. In 1997, after Khalifa's death, Gardner devoted a short article to the subject while a columnist for the Skeptical Inquirer.
Criticism
Common critiques of numerological claims also apply to the Quran Code. Critics often invoke the concept of stochastic processes to explain how seemingly mystical patterns could appear in any large dataset. One such critic was Bilal Philips, who argued that Rashad Khalifa's "miracle 19" theory was a hoax based on falsified data, misinterpretations of the Quran's text, and grammar inconsistencies.
Additionally, since early Quran manuscripts can contain orthographic differences in certain passages, the precise number of letters in those sections can be unclear. For example, since the frequency of the letter Alif is subject to debate, there is not an universally agreed letter count in the Alif initialized Surahs. However, to prove his theory Khalifa chose those versions of the text that included letter frequencies divisible by 19. Additionally, Khalifa claimed that the initial "Nūn" in Surah 68 should be spelled as to include an additional Nūn: "Nūn Wāw Nūn" in place of the orthodox spelling, "Nūn". This allowed Khalifa to claim that there are 133 (19×7) Nūns in Surah 68, instead of 132, which is not a multiple of 19. However, Khalifa's spelling does not appear in any Quranic manuscripts. He also assumed that the correct spelling or reading of the word "basṭatan", which occurs in Surah 7, verse 69, contains the Arabic letter Sīn instead of the letter Suād, which is the conventional spelling. He based this assertion on the Samarkand Codex, an 9th century Quranic manuscript which includes a spelling with the letter Sīn in place of Suād.
Khalifa also claimed that two verses in the Quran, specifically Surah 9, verses 128 and 129, were humanly added, and should not be included. He supports this claim by the hadith Sahīh al-Bukhārī 7425, according to which Zaid ibn Thābit, tasked by Abu Bakr with compiling the Quran, found only one witness to attest to the validity of verses 9:128–129, Khuzaima al-Ansari. Thus, Khalifa claimed that the Quran has only 6346 verses instead of the traditional count of 6348. The omission of these verses is integral to his theory; if these two verses are taken into account, there are 2699 occurrences of the word "Allah" and 115 occurrences of the word "Rahim", neither of which are multiples of 19.
Furthermore, the version of the Quran code is questioned, as it is only used for certain aspects or Quranic initials. Surahs that are not initiated are not fully examined in this context. Since early Quran manuscripts differ orthographically in certain passages, it makes it difficult to reconstruct an "urtext" – or in another expression a "primordial text" – for the Quran, which in turn is used for letter enumerations as well as gematria.
See also
Bible code
References
Bibliography
External links
Various hypothetical mathematical considerations regarding the Quran code
Video presentation of certain aspects of Code 19
"171 examples of the mathematical System"
Code
Quranism
Numerology | Quran code | [
"Mathematics"
] | 1,603 | [
"Numerology",
"Mathematical objects",
"Numbers"
] |
67,885,638 | https://en.wikipedia.org/wiki/Sergey%20Bolotin | Sergey Vladimirovich Bolotin (Сергей Владимирович Болотин, born 1 December 1954 in Moscow) is a Russian mathematician, specializing in dynamical systems of classical mechanics.
Biography
Bolotin graduated in 1976 from the Faculty of Mechanics and Mathematics of Moscow State University. There he received in 1981 his Candidate of Sciences degree (PhD) with thesis Либрационные движения обратимых механических систем (Librational motions of reversible mechanical systems). He received in 1998 his Russian Doctor of Sciences degree (habilitation) with thesis Двоякоасимптотические траектории и условия интегрируемости гамильтоновых систем (Double-asymptotic trajectories and integrability conditions for Hamiltonian systems).
Since 1998 Bolotin is a professor in the Department of Theoretical Mechanics, Faculty of Mechanics and Mathematics, Moscow State University. He is now the head of the Mechanics Department of the Steklov Institute of Mathematics. His research deals with dynamical systems of classical mechanics, Hamiltonian systems, and variational methods. He has supervised four PhD (Candidate of Sciences) students. He is the author or coauthor of over 75 scientific publications, including a textbook on theoretical mechanics (2010). He has served on the editorial board of the journal Regular and Chaotic Dynamics.
In 1994 he was an invited speaker with talk Invariant Sets of Hamiltonian Systems and Variational Methods at the International Congress of Mathematicians in Zurich. In 2016 he was elected a corresponding member of the Russian Academy of Sciences.
As a hobby, Bolotin sails in Olympic class Finn dinghies.
His brother Yuri Vladimirovich Bolotin (born December 1, 1954) is a professor at Moscow State University. Both brothers in 2020 became champions of Russia in the class of yachts "Carter 30".
Selected publications
References
1954 births
Living people
Moscow State University alumni
Academic staff of Moscow State University
Academic staff of the Steklov Institute of Mathematics
20th-century Russian mathematicians
21st-century Russian mathematicians
Dynamical systems theorists
Russian systems scientists
Mathematical physicists
Russian male sailors (sport) | Sergey Bolotin | [
"Mathematics"
] | 523 | [
"Dynamical systems theorists",
"Dynamical systems"
] |
67,886,008 | https://en.wikipedia.org/wiki/Alabay%20Statue | Alabay Statue () is a gilded statue that stands on Ashgabat, Turkmenistan. The 49 feet (15 m) tall gilded statue (the statue itself is 29 feet, the pedestal is 20 feet), depicts a Alabay dog. The statue was created by Turkmen artist Sargart Babaev with the President Gurbanguly Berdimuhamedow's initiative in 2020.
Appearance
The height of the dog's figure is 6 meters, it is installed on a pedestal 9 meters high. The 15-meter monument is located on an area with a diameter of 36 meters.
It is installed at a roundabout along Magtymguly Avenue, in a vast area between Taslama and Tehran streets.
History
The idea to erect a monument appeared in 2017, with several designs presented in October.
Construction began in 2019 and completed in autumn 2020.
The official opening of the statue took place in November 2020.
References
External links
Berdimuhamedov's poem dedicated to Alabay
Buildings and structures in Ashgabat
2020 sculptures
Asian sculpture
Colossal statues
Sculptures of dogs | Alabay Statue | [
"Physics",
"Mathematics"
] | 221 | [
"Quantity",
"Colossal statues",
"Physical quantities",
"Size"
] |
67,886,069 | https://en.wikipedia.org/wiki/SamyGO | The SamyGO project is software used to run aftermarket firmware of smart TVs by Samsung. It consists of a forum which contains various methods for rooting the smart TVs.
Features
The project has implemented NFS and Samba file sharing, playback from USB devices and unlocked the use of Wi-Fi dongles not authorized by Samsung.
References
External links
Samsung
Smart TV
Hacking (computer security) | SamyGO | [
"Technology"
] | 82 | [
"Multimedia",
"Smart TV"
] |
67,886,123 | https://en.wikipedia.org/wiki/NetCast | NetCast (later Smart TV, then Legacy Platform) is a Smart TV platform based on Linux, built by LG Electronics that was preinstalled on their smart TVs between 2009 and 2014. LG has signed partnerships with various companies to provide services on the TV. It includes YouTube, AccuWeather, Orange Mobile, Maxdome, CinemaNow, Netflix and more apps that can be downloaded from the internet. LG has combined local and global services to provide the most relevant content. In 2011, LG added the LG Apps Store to the platform. It allowed users to install applications which were not previously included on their TVs. The platform was succeeded by WebOS.
History
NetCast, or NetCast Entertainment Access, was announced by LG at CES 2009. At launch, it gave users access to Netflix, YouTube and Yahoo! Widgets. Later, support for Vudu has also been added.
In 2010, LG introduced the LG Magic Remote, which is a TV remote designed to be used with their Smart TV system. The motion-controlled remote allowed users to move it in the air to control a mouse cursor, similar to the Nintendo Wii. The technology for the remote was provided by Hillcrest Labs, and is still used today.
NetCast was rebranded to Smart TV in 2011, which was shown first at CES. In 2011, the company Marmalade Technologies added NetCast support to their Marmalade SDK.
TechRadar considered it "just plain disappointing" in a 2010 review. In a 2011 review, they noted that NetCast was first a mere placeholder with only three services, but noted that more apps had been added via a firmware update.
The OpenLGTV project has added homebrew widgets to the NetCast platform.
The software logged the filenames that were accessed and uploaded them to servers of LG.
NetCast and Smart TV were replaced by the WebOS platform in 2014. Starting in 2015, all smart TVs by LG were based on webOS.
See also
Orsay (operating system) - the direct competitor to NetCast made by Samsung used in its Internet@TV and Smart TV lines from 2009 to 2014 before being replaced by Tizen in 2015
References
External links
NetCast platform specifications
LG Electronics
Smart TV | NetCast | [
"Technology"
] | 473 | [
"Multimedia",
"Smart TV"
] |
67,886,971 | https://en.wikipedia.org/wiki/1991%20Ghotki%20train%20crash | On 8 June 1991, a train crash killed over 100 people in Ghotki, Sindh, Pakistan. A passenger train carrying 800 passengers from Karachi to Lahore crashed into a parked freight train.
See also
List of railway accidents and incidents in Pakistan
References
1991 in Pakistan
1991 disasters in Pakistan
1991 train crash
June 1991 events in Pakistan | 1991 Ghotki train crash | [
"Technology"
] | 66 | [
"Railway accidents and incidents",
"Rail accident stubs"
] |
67,888,569 | https://en.wikipedia.org/wiki/Urocystis%20alopecuri | Urocystis alopecuri is a fungal plant pathogen in the family Urocystidiaceae. Known as 'Foxtail Smut'.
It is found on Alopecurus species; such as Alopecurus aequalis, Alopecurus arundinaceus, Alopecurus geniculatus, Alopecurus myosuroides and Alopecurus pratensis in Europe.
References
Fungal plant pathogens and diseases
Wheat diseases
Ustilaginomycotina
Fungi described in 1877
Fungus species | Urocystis alopecuri | [
"Biology"
] | 111 | [
"Fungi",
"Fungus species"
] |
67,889,146 | https://en.wikipedia.org/wiki/Allotropes%20of%20silicon | Allotropes of silicon are structurally varied forms of silicon.
Amorphous silicon
Amorphous silicon takes the form of a brown powder.
Crystalline silicon
Crystalline silicon has a metallic luster and a grayish color. Single crystals can be grown with the Czochralski process. Crystalline silicon can be doped with elements such as boron, gallium, germanium, phosphorus or arsenic. Doped silicon is used in solid-state electronic devices, such as solar cells, rectifiers and computer chips.
Silicon crystallizes in the same pattern as diamond, viewable as two interpenetrating face-centered cubic primitive lattices. The cube measures 0.543 nm on a side.
Silicene
Silicene is a two-dimensional system with a hexagonal honeycomb structure similar to that of graphene. Silicene has different characteristics than graphene. It has a periodically buckled topology; interlayer coupling is much stronger; and its oxidized form, 2D silica, has a different chemical structure from graphene oxide. It was first created in 2010.
Penta-silicene is a two-dimensional system with pentagonal structure similar to that of penta-graphene. The structure was first synthesized in 2005.
is an orthorhombic crystalline Si allotrope. It was first synthesized in 2014. Creating the allotrope involved forming , a polycrystalline compound with help from a tantalum capsule, high temperature, and a 1,500 ton multi-anvil press that gradually reached a pressure of . Next it was "degassed" in a vacuum at for eight days. The result was a zeolite-type structure.
has a quasi-direct band gap (specifically a small and almost flat indirect band gap). It can conduct electricity more efficiently than diamond-structured silicon. It can absorb and emit light. It is composed of five-, six-, and eight-membered rings. Small atoms and molecules could pass through the associated holes.
Si24 can be doped as both p- and n-type, and the dopants are readily ionized. Boron and phosphorus the most likely dopants.
Potential applications include energy storage and filtering.
4H silicon
4H silicon is a bulk, highly ordered hexagonal 4-layer crystalline form of . Optical absorption measurements revealed an indirect band gap near 1.2 eV, in agreement with first principles calculations.
Silicyne
1-dimensional silicyne is analogous to the carbon allotrope carbyne, being a long chain of silicons, instead of carbons. 2-dimensional silicyne is analogous to the carbon allotrope graphyne.
References
Allotropes of silicon | Allotropes of silicon | [
"Chemistry"
] | 565 | [
"Allotropes of silicon",
"Allotropes"
] |
67,889,550 | https://en.wikipedia.org/wiki/Connie%20C.%20Lu | Connie C. Lu is a Taiwanese-American inorganic chemist and a professor of chemistry at the University of Bonn. She was previously a professor of chemistry at the University of Minnesota, Twin Cities. Lu's research focuses on the synthesis of novel bimetallic coordination complexes, as well as metal-organic frameworks. These molecules and materials are investigated for the catalytic conversion of small molecules like as N2 and CO2 into value-added chemicals like ammonia and methanol. Lu is the recipient of multiple awards for her research, including the National Science Foundation CAREER Award and the Sloan Research Fellowship in 2013, and an Early Career Award from the University of Minnesota's Initiative for Renewable Energy and the Environment in 2010.
Early life and education
Lu grew up in Miami, Florida, the daughter of immigrants from Taiwan. She studied chemistry at the Massachusetts Institute of Technology, earning her B.S. in 2000. As an undergraduate, she conducted research under Prof. Vernon Ingram on peptides that ameliorate amyloid beta neurotoxicity.
She then went on to graduate studies at the California Institute of Technology, where she studied novel coordination chemistry and small molecule reactivity with Prof. Jonas C. Peters. Lu's doctoral work focused on the reactivity of zwitterionic palladium(II) complexes with CO, ethylene and amines, as well as tetrahedral manganese complexes and reductive cleavage of CO2 with an iron(I) complex. She earned her Ph.D. in 2006, with a thesis entitled The Chemistry of Tris(phosphino)borate Manganese and Iron Platforms.
Lu conducted postdoctoral studies at the Max Planck Institute for Bioinorganic Chemistry from 2006 to 2009, under the mentorship of Prof. Karl Wieghardt. Under Wieghardt, Lu studied first-row transition metal complexes synthesized with redox non-innocent α-iminopyridine ligands. Lu also reported the synthesis and characterization of a chromium iminyl radical complex, using the α-iminopyridine ligand system.
Independent career
In 2009, Lu began her independent career at the University of Minnesota, Twin Cities as an assistant professor in the department of chemistry. She was promoted to associate professor with tenure in 2015, and full professor in 2020. She moved her laboratory to the University of Bonn in 2022.
Her research focuses on the synthesis and characterization of bimetallic complexes, especially those that contain a metal-metal bond. The Lu group has developed a series of trianionic, tripodal ligands that can coordinate two metals at close proximity, allowing for the formation for a metal-metal bond in a coordination complex. The metal-metal bond order can range from bond orders of less than one to a quintuple bond, as between manganese and chromium in a complex reported in 2013, and between two chromium atoms in a complex reported in 2015.
These coordination complexes are also active for catalytic reactions of small molecules, such as the silylation of nitrogen by a dicobalt complex, and alkene hydrogenation by nickel-group 13 element complexes.
Awards
Lu was named an Outstanding Reviewer of the journal Chemical Society Reviews in 2018 and 2019, featured in a 2018 JACS Young Investigators Virtual Issue, and named a Kavli Frontiers of Science Fellow in 2013. She has been honored with invited speaking engagements, as she gave a plenary lecture at a Royal Society of Chemistry Dalton Conference in 2018, and the Association for Cultural Diversity in Chemistry Lecture at the University of Pennsylvania in 2016. In 2017, Lu was invited to be a speaker at the Indo-US Workshop on Organometallic Chemistry and a Inorganic Chemistry Young Outstanding Upcoming speaker at Symposium on Advanced Biological Inorganic Chemistry in Kolkata, India.
Memberships
Lu is a member of the American Chemical Society and the Royal Chemical Society, and has served on the editorial advisory board of Chemical Society Reviews since 2016. She also served on the Inorganic Chemistry editorial advisory board from 2016 to 2018.
References
External links
Research highlight video from University of Minnesota's College of Science and Engineering, 2017
Living people
American women chemists
Inorganic chemists
University of Minnesota faculty
Massachusetts Institute of Technology alumni
California Institute of Technology alumni
Year of birth missing (living people)
21st-century American women | Connie C. Lu | [
"Chemistry"
] | 878 | [
"Inorganic chemists"
] |
67,890,154 | https://en.wikipedia.org/wiki/HD%2035759 | HD 35759 is a star with an orbiting exoplanet located in the circumpolar constellation Camelopardalis. With an apparent magnitude of 7.74, it's impossible to see with the unaided eye, but can be seen with binoculars. The distance to this system is 232 light years based on parallax measurements, and it is drifting closer with a heliocentric radial velocity of −12.6 km/s.
This is a G-type star with 15% more mass than the Sun, but has 1.76 times the radius. It radiates at about 3 solar luminosities, and has an effective temperature of 5,927 K, which gives it a yellow hue. HD 35759 is slightly enriched in metals, with having 9.6% more iron abundance than the Sun. Like many older G-type stars, HD 35759 rotates rather slowly, with a projected rotational velocity of 3 km/s.
Planetary System
In 2016, a super-jovian exoplanet was discovered orbiting the star on an eccentric orbit. Since the planet was discovered using doppler spectroscopy, its radius and true mass is unknown.
References
G-type stars
Planetary systems with one confirmed planet
Camelopardalis
35759
025883 | HD 35759 | [
"Astronomy"
] | 263 | [
"Camelopardalis",
"Constellations"
] |
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