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66,518,343 | https://en.wikipedia.org/wiki/Peter%20H.%20Barry | Peter H. Barry is an American geochemist who is an associate scientist in the marine chemistry and geochemistry department at the Woods Hole Oceanographic Institution. He uses noble gases and stable isotopes to understand the volatile history and chemical evolution of Earth, including the dynamic processes of subduction, mantle convection and surface volcanism, which control the redistribution of chemical constituents between the crust and mantle reservoirs. Barry’s main research focus has been on high-temperature geochemistry, crust-mantle interactions and the behavior of volatile fluids in the lithosphere. He also studies crustal systems, the origin of high helium deposits, including hydrocarbon formation and transport mechanisms.
Barry earned his bachelor's degree in 2004 from SUNY Geneseo, where he studied geology. He earned his master's degree in 2011 and PhD in 2012 from Scripps Institution of Oceanography. He was an NSF Postdoctoral Fellow at University of Tennessee and continued his postdoctoral research at the University of Oxford during 2014–2018 before becoming an assistant scientist at the Woods Hole Oceanographic Institution in 2019. In 2018, he won the DCO Emerging Leader Award from the Deep Carbon Observatory (DCO) and Alfred P. Sloan Foundation in part for leading the Biology Meet Subduction project. The short science documentary produced within the framework of the project was awarded the first place price at the Goldschmidt Orbit Science Documentary Festival.
Barry's major contributions to science to date include explaining the End-Permian Extinction event, the distribution of major reservoirs of helium gas on Earth and discovering new sinks of CO2 in subduction zones. Several of his discoveries have been covered by international media outlets.
References
Year of birth missing (living people)
Living people
Place of birth missing (living people)
American geochemists
State University of New York at Geneseo alumni
Scripps Institution of Oceanography alumni
Academics of the University of Oxford
American expatriate academics in the United Kingdom
University of Tennessee faculty
Woods Hole Oceanographic Institution | Peter H. Barry | [
"Chemistry"
] | 402 | [
"Geochemists",
"American geochemists"
] |
66,518,962 | https://en.wikipedia.org/wiki/Thomas%20McKay%20%28Alaska%20politician%29 | Thomas W. McKay (born ca. 1959) is an American Republican politician from Alaska. He represents District 15 as a member of the Alaska House of Representatives.
References
External links
Thomas McKay at Ballotpedia
Engineers from Alaska
Petroleum engineers
Living people
Politicians from Anchorage, Alaska
Republican Party members of the Alaska House of Representatives
Year of birth missing (living people)
21st-century members of the Alaska Legislature | Thomas McKay (Alaska politician) | [
"Engineering"
] | 80 | [
"Petroleum engineers",
"Petroleum engineering"
] |
66,521,027 | https://en.wikipedia.org/wiki/Vanadyl%20ribonucleoside | Vanadyl ribonucleoside is a potent transition-state analog of ribonucleic acid and potent inhibitor of many species of ribonuclease formed from a vanadium coordination complex and one ribonucleoside. Vanadium's [Ar] 3d3 4s2 electron configuration allows it to make five sigma bonds and two pi bonds with adjacent atoms.
History
RNA is notoriously unstable and vulnerable to ribonucleases, which has thus been an obstacle to the production and analysis of the cellular transcriptome. First referenced by Berger et al., the substance was used to prevent the digestion of RNA during isolation from white blood cells, and was rapidly adopted for such purposes as the acquisition of RNA from green beans.
Production
Vanadyl ribonucleoside is produced by combining vanadyl sulphate with various ribonucleosides (such as guanosine) in a 1:10 molar ratio.
Use
Vanadyl ribonucleoside, along with other RNase inhibitors, has been a staple of molecular biochemistry since its invention by allowing for the stability of RNA in its storage and use.
References
Ribonucleases
Molecular biology | Vanadyl ribonucleoside | [
"Chemistry",
"Biology"
] | 251 | [
"Biochemistry",
"Molecular biology"
] |
66,521,359 | https://en.wikipedia.org/wiki/Cobalt%20ferrite | Cobalt ferrite is a semi-hard ferrite with the chemical formula of CoFe2O4 (CoO·Fe2O3). The substance can be considered as between soft and hard magnetic material and is usually classified as a semi-hard material.
Uses
It is mainly used for its magnetostrictive applications like sensors and actuators thanks to its high saturation magnetostriction (~200 ppm). CoFe2O4 has also the benefits to be rare-earth free, which makes it a good substitute for Terfenol-D. Moreover, its magnetostrictive properties can be tuned by inducing a magnetic uniaxial anisotropy. This can be done by magnetic annealing, magnetic field assisted compaction, or reaction under uniaxial pressure. This last solution has the advantage to be ultra fast (20 min) thanks to the use of spark plasma sintering. The induced magnetic anisotropy in cobalt ferrite is also beneficial to enhance the magnetoelectric effect in composite.
Cobalt ferrite can be also used as electrocatalyst for oxygen evolution reaction and as material for fabricating electrodes for electrochemical capacitors (also named supercapacitors) for energy storage. These uses take advantage of the redox reactions occurring at the surface of the ferrite. Cobalt ferrite prepared with controlled morphology and size to enhance the surface area, and thus the number of active sites, has been published. One disadvantage of the cobalt ferrite for some applications is their low electrical conductivity. Nanostructures of cobalt ferrite with different shape can be synthesized on conducting substrates, such as reduced graphene oxide, to alleviate this disadvantage.
See also
Ferrite
References
Ceramic materials
Ferromagnetic materials
Ferrites
Cobalt(II) compounds
Iron(III) compounds | Cobalt ferrite | [
"Physics",
"Engineering"
] | 386 | [
"Materials stubs",
"Ferromagnetic materials",
"Materials",
"Ceramic materials",
"Ceramic engineering",
"Matter"
] |
66,521,563 | https://en.wikipedia.org/wiki/TOI-178 | TOI-178 is a planetary system in the constellation Sculptor around which six planets have been observed, at at least five of which orbit in a chain of Laplace resonances, which constitute one of the longest chains yet discovered in a system of planets. The system also has unusual variations in the densities among the planets.
The system is 205 light-years away, which is relatively close, implying that such systems may be relatively common. The brightness of the star, TOI-178, facilitates followup observations, which make it an ideal system in which to expand our understanding of planet formation and evolution.
The planetary system was confirmed by data provided by five different planet search projects. After TESS provided first hints at a system with an interesting resonant chain, additional observations to refine the measurement and confirm the finding were provided by CHEOPS, ESPRESSO, NGTS and SPECULOOS. Over the coming years, observations of transit-timing variations in the transits of the various planets, which are expected to range from minutes to tens of minutes, should help pin down the planetary masses and uncover the eccentricities of the various orbits.
Planetary system and orbital resonance
Of the six planets, named TOI-178b through TOI-178g as per IAU convention, the outer five are locked in a chain of Laplace resonances. The periods of the planets, in days, revolving around the star are b = 1.91, c = 3.24, d = 6.56, e = 9.96, f = 15.23, and g = 20.71. While this is not a perfect integer ratio, there exists a frame of reference that rotates by roughly 1.37° day−1, in which successive conjunctions of the planets form a repeating pattern. For an observer rotating within this frame of reference, the planets c through g form a chain of resonance that can be expressed as 2:4:6:9:12 in ratios of periods, or as 18:9:6:4:3 in ratios of orbits, which means that for every eighteen revolutions of the planet c, the planet d completes nine, the planet e six, the planet f four, and the planet g three.
In addition, the planet b orbits close to where it would also be a part of the same resonant chain. In a slightly bigger orbit of period of ~1.95 days, it would form a 3:5 resonance with the planet c in the same corotating frame of reference as the other five. It is possible that the entire system originally formed in one long resonant chain, but later the innermost planet was pulled out of it, perhaps by tidal interactions.
See also
Kepler-80 – another system with five planets in an orbital resonance
Kepler-223
TOI-178c—A super earth in the TOI-178 system
References
Sculptor (constellation)
K-type main-sequence stars
178, TOI
J00291228-3027133
Planetary systems with six confirmed planets
Planetary transit variables | TOI-178 | [
"Astronomy"
] | 621 | [
"Constellations",
"Sculptor (constellation)"
] |
68,032,808 | https://en.wikipedia.org/wiki/Balneolaceae | Balneolaceae is a family of bacteria.
Phylogeny
The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI).
See also
List of bacterial orders
List of bacteria genera
References
Bacteria families | Balneolaceae | [
"Biology"
] | 64 | [
"Bacteria stubs",
"Bacteria"
] |
68,032,857 | https://en.wikipedia.org/wiki/Balneolales | Balneolales is an order of bacteria.
Phylogeny
The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI).
See also
List of bacterial orders
List of bacteria genera
References
Bacteria orders | Balneolales | [
"Biology"
] | 64 | [
"Bacteria stubs",
"Bacteria"
] |
68,033,348 | https://en.wikipedia.org/wiki/Concepticon | Concepticon is an open-source online lexical database of linguistic concept lists (word lists). It links concept labels (i.e., word list glosses) in concept lists (i.e., word lists) to concept sets (i.e., standardized word meanings).
It is part of the Cross-Linguistic Linked Data (CLLD) project, which is hosted by the Max Planck Institute for the Science of Human History in Jena, Germany. Version 1.0 was released in 2016.
Concept
Concept lists in the Concepticon include:
Swadesh list (100 items, 207 items, etc.)
Swadesh–Yakhontov list
Dolgopolsky list
Leipzig–Jakarta list
ASJP list
See also
Conceptualization (information science)
Ontology (information science)
Intercontinental Dictionary Series
References
List, Johann Mattis & Rzymski, Christoph & Greenhill, Simon & Schweikhard, Nathanael & Pianykh, Kristina & Tjuka, Annika & Hundt, Carolin & Forkel, Robert (eds.) 2021. CLLD Concepticon 2.5.0 [Data set]. Zenodo.
External links
Langavia Dictionary
Synonyms Dictionary
Lexical databases
Knowledge representation
Computational linguistics
Open data
Cross-Linguistic Linked Data
Linguistics lists
Word lists
Ontology (information science) | Concepticon | [
"Technology"
] | 277 | [
"Natural language and computing",
"Computational linguistics"
] |
68,034,443 | https://en.wikipedia.org/wiki/Mark%20Stockman | Mark Stockman (born Mark Ilyich Shtokman; July 21, 1947 – November 11, 2020) was a Soviet-born American physicist. He was a professor of physics and astronomy at Georgia State University. Best known for his contributions to plasmonics, Stockman has co-theorized plasmonic lasers, also known as spasers, in 2003.
Biography
Stockman was born on July 21, 1947, in Kharkiv, Ukrainian Soviet Socialist Republic to a Jewish family with Cantonist roots. His father, Ilya Stockman, was a mining engineer and a World War II veteran. After his father became a faculty member at the Dnepropetrovsk Higher Mining School, his family relocated to Dnepropetrovsk.
Stockman completed his secondary education at the Republican Specialized Physics and Mathematics Boarding School in Kyiv. Following his graduation, he enrolled to Kyiv State University to study physics; he subsequently transferred to Novosibirsk State University, where he obtained his Master of Science in 1970. He completed his PhD at Institute of Nuclear Physics in Novosibirsk in 1974 under the supervision of Spartak Belyaev and Vladimir Zelelevinsky. His doctoral research work concentrated on nuclear physics. During his PhD, he met and married Branislava Mezger and had a son, Dmitriy, in 1978.
No longer being interested in nuclear physics, Stockman transferred to the Institute of Automation and Electrometry in Novosibirsk following his PhD and started working on nonlinear optics as a research scientist under the supervision of Sergey Rautian. He habilitated in 1989, obtaining his DSc. In 1990, with the invitation of Thomas F. George, he left for the United States with his family to take a research position at University at Buffalo in Buffalo, New York. In the meanwhile, he held a visiting position at Washington State University. In 1996, he relocated to Atlanta, Georgia to join the faculty of Georgia State University, where he obtained his full professorship in 2001. Stockman also held visiting positions at Max Planck Institute of Quantum Optics, University of Stuttgart, École normale supérieure Paris-Saclay and ESPCI Paris.
In 2012, Stockman founded the Center for Nano Optics at Georgia State University. He was a fellow member of the American Physical Society, The Optical Society and SPIE. He died on November 11, 2020, in Atlanta.
Research
Stockman's research concentrated in the field of nanoplasmonics; he was described as a pivotal figure in the research field. In 2003, alongside David J. Bergman, he theorized the plasmonic lasers known as "spasers," which involved the stimulated emission of localized surface plasmon via metallic nanoparticles instead of conventional optical cavities. They coined the acronym spaser as "surface plasmon amplification by stimulated emission of radiation." Stockman further developed the theory of spasers for optical amplification and ultrashort pulse generation. His research also focused on plasmonic hotspots in nanostructures and nanofocusing in adiabatic tapers, as well as ultrafast active plasmonics.
Selected publications
References
Notes
External links
1947 births
2020 deaths
Scientists from Kharkiv
20th-century American physicists
21st-century American physicists
Jewish American physicists
Georgia State University faculty
Optical physicists
American nanotechnologists
Fellows of Optica (society)
Fellows of the American Physical Society
Soviet physicists
Soviet Jews
Soviet emigrants to the United States
Jewish Ukrainian scientists
Jewish Russian physicists
American people of Ukrainian-Jewish descent
American people of Russian-Jewish descent
Taras Shevchenko National University of Kyiv alumni
Novosibirsk State University alumni
American condensed matter physicists
People from Atlanta
Scientists from Georgia (U.S. state)
Naturalized citizens of the United States
Metamaterials scientists
Laser researchers
Fellows of SPIE
21st-century American Jews
20th-century American Jews | Mark Stockman | [
"Materials_science"
] | 808 | [
"Metamaterials scientists",
"Metamaterials"
] |
68,035,103 | https://en.wikipedia.org/wiki/Institution%20of%20Diploma%20Engineers%2C%20Bangladesh | Institution of Diploma Engineers, Bangladesh, widely known as IDEB is a professional organization for Diploma Engineers and Diploma Architects in Bangladesh, which was established on 8 November 1970. The aim of this company is to make a union partnership among diploma engineers to serve in the engineering community.
IDEB is a multidisciplinary organization of engineering society which was dedicated to developing the knowledge, understanding and practice of engineering sector. IDEB also has 11 members of advisory council.
Membership
People with engineering diplomas, and/or a person having post Matriculation or Post Secondary School Certificate (SSC) with 3 or 4 years of schooling in engineering and technology on successful completion be awarded a Diploma in Engineering by any university or Education Board of UK, US, India, Pakistan and Bangladesh and/or as recognized by the government of Bangladesh is eligible for membership of IDEB. IDEB offered six category membership i.e. student member, general member, fellow member, life member, donor member and honorary member.
General member
Any individuals who have attained Diploma in Engineering from a Bangladesh government-recognized educational institute and obtained a certificate from Bangladesh Technical Education Board (BTTB) are eligible for the membership of this institution. But they have to apply to the institute for the membership and be awarded with membership certificate.
Student member
All students of the Diploma-in Engineering course in Polytechnic and Technical Institute and their equivalents shall be eligible to become student members of the Institution subject to be conditions as prescribed in the constitution or as may be decided by the Central Executive Committee from time to time.
Life member
Any member shall be entitled to be a life member subscribing an amount of Tk. 10,000/- (Ten Thousand) to the IDEB Fund at a time.
Fellow member
Any member who has completed 25 years of membership who were associated with the activities of the Institution and having the expertise in engineering work and have shall be eligible to be the Fellow Member. Any such member applied for, the District Executive Committee shall prepare detailed particulars and submit to the Central Executive Committee. The CEC shall examine the information and nominate as Fellow Member and eventually award the Fellow Membership Certificate.
Donor member
(a) Any member engineer donating a fixed amount to the "Build construction fund" shall be entitled to be "Donor Member".
(b) Any person on being sympathized to the activities of IDEB donates 1 (One) Lac Taka to IDEB fund subjected to the approval of the central executive committee may be the donor member of IDEB.
Honorary member
A person who does not fulfill the conditions as mentioned in clause - 01 of Article- 03 (03.01) of constitution, but having sympathy with the objective and principles of this Institution or having some outstanding achievements in the field of Engineering and who assist in the healthy growth for development of the Institution, shall be eligible to be nominated for Honorary Member of the Institution with the consent and Institution, provided that the number of such membership shall not be more than 1% (One Percent) of the total enrolled members.
Division and cell
Study & Research Division
IDEB formed a research and study cell to contribute to the nation and the people in the development works. This cell conducts studies on various issues and problems and suggests recommendations that may help the planners and policy makers to adopt appropriate policies and plans in the various technological fields like irrigation, flood control, roads and highways, electricity, energy, water logging in cities / towns, education, health, sanitation, housing and all other productive of commonalities. The institution has also been conducting activities viz. submitting memorandum, holding press conference, meeting with authorities to press the demands of the members and to correct and revise the wrong national policies, projects and programs etc.
ICT & Innovation Cell
IDEB has an ICT & Innovation cell to empower its members in ICT & Encourage its members in Innovation Activity. This cell has young leadership with many success record. This cell has two wings IDEB Women's ICT Wing & Innovation Coordination committee.
IDEB Women's ICT Wing
Innovation Coordination committee
Library
The IDEB maintain a library namely "IDEB Shadhinota Pathagar" at 2nd floor of IDEB Bhaban, 160/A, Kakrail VIP Road, Dhaka-1000, Bangladesh with various type of books viz. Engineering, Technology, Social Science, General Science, Philosophy, Historical and other disciplines. There is a fixed program to collect a number of books every year regularly to enrich the library.
IDEB member engineers and research person & students from different stage of society to visit the library regular for seeking knowledge by readout the reserved books. The management authority of library is proud for spreading knowledge to society by maintaining it. We are seeking whole hearten co-operation & help from government & non-government official, intellectual, writer & donor agencies for abounding the library.
Publication
The IDEB publishes a socio-technological monthly journal named "KARIGAR" meaning "THE ARTISAN". A Board of Editors consisting of reputed and learned Diploma Engineers are entrusted with the publication of the journal. They select the quality articles for it. Besides, special supplement also published from time to time as and when necessary. Quite a good number of intellectuals contribute their articles regularly.
To create public awareness on regarding science and technology of this novel effort's already been quite welcome by the intellectual community of the society. The editorial panel of the Journal is working to improve the quality of the uninterrupted publications in demand of present era. To endless support & cooperation of many readers & admirers in the last half decade we are very pledge and go-ahead to reach our goal.
Conference
IDEB has organized several National and International Conferences in Engineering, Technology & Education.
International Conference on TVET for Sustainable Development 2015
International Conference on TVET for Sustainable Development was jointly organized by IDEB and CPSC, Manila. It was first international conference on Technical Voactional Education & Training (TVET) in Bangladesh.
International Conference on "Skills for the Future World of Work and TVET for Global Competitiveness 2017"
The International Conference on "Skills for the Future World of Work and TVET for Global Competitiveness" has taken place in July 2017 at the Institution of Diploma Engineers Bangladesh (IDEB), Dhaka, Bangladesh. The conference was jointly organizing by IDEB and Colombo Plan Staff College (CPSC), Manila, Philippines. in Association with Ministry of Education (MoE) Government of Bangladesh, National Skills Development Council (NSDC) Where International Labour Organization (ILO), Directorate of Technical Education (DTE) and Bangladesh Technical Education Board, a2i, ESD Australia, IOM, PKSF, STEP, BMET, FBCCI, BEF was the Co-partner of the Conference.
This international conference was addressed the future demand of skilled manpower and the acceleration process to ensure the demand based quality Technical and Vocational Education & Training (TVET).
People's Engineering Day
People's Engineering Day is being celebrated throughout the country on the founding anniversary day of the Institution of Diploma Engineer's Bangladesh (IDEB) on 8 November each year of the Headquarters and at all centers in a befitting manner to animate science & technology to the people. At the eve of the day, taken programs have been brought out to the Nation through News conference. Special supplementary is published in National Dailies and special picture broadcast participating leaders in Bangladesh Television and other Electronic Media. The messages are being given by Honorable President, Prime Minister, National Parliament Speaker, Opposition Leader, Member of Cabinet and different political parties' chief on the occasion. Colorful rally's being brought out by the participating member Engineers and polytechnic teachers and students. On the occasion of Peoples Engineering Day IDEB arranged week-wide program with various discussion meeting, seminar, technical lecture session on national issues and blood donation program is a regular program considering the distressed humanity.
References
Engineering societies
Professional associations based in Bangladesh
Technological institutes of Bangladesh | Institution of Diploma Engineers, Bangladesh | [
"Engineering"
] | 1,611 | [
"Engineering societies"
] |
68,037,102 | https://en.wikipedia.org/wiki/Jaak%20Peetre | Jaak Peetre (29 July 1935, in Tallinn – 1 April 2019, in Lund) was an Estonian-born Swedish mathematician. He is known for the Peetre theorem and Peetre's inequality.
Biography
Jaak Peetre's father was Arthur Peetre (1907–1989), an Estonian jurist, historian, archivist, and from 1941 to 1942 mayor of Pärnu. Jaak Peetre went to Sweden with his parents and brother in 1944. At Lund University he graduated with BSc in 1956 and PhD in 1959. His thesis advisor was Åke Pleijel. At Lund University, Peetre was an assistant professor from 1956 to 1959, an associate professor from 1960 to 1963, and full professor from 1963 to 1988. He was briefly in 1988 a visiting professor at the University of Madrid and was from 1988 to 1992 a visiting professor at Stockholm University. At Lund University he was a lecturer from 1993 to 1997, an assistant professor from 1997 to 2000, and professor emeritus from 2000. He was also a visiting professor at New York University for the academic year 1960–1961 and at University of Maryland for the academic year 1961–1962.
Peetre's research deals with ordinary and partial derivative differential equations, operator interpolation spaces, singular integrals and Besov spaces, differential geometry, Clifford analysis, Fock space and Hankel operators, Fourier and harmonic analysis. Bernard Malgrange, Jacques-Louis Lions, and Peetre were pioneers of modern interpolation theory. In the early 1990s, Peetre's research focused on multilinear forms, especially trilinear forms. He was the author or coauthor of more than 230 research papers. He was the thesis advisor for 8 doctoral students. In 1970 he was an Invited Speaker at the International Congress of Mathematicians in Nice. He gave lectures at more than 30 international mathematical congresses and conferences and in many cases was among the organizers. He was a member of the editorial boards of several international mathematical journals.
In 1984 he was elected a member of the Swedish Royal Academy of Sciences. From 1984 to 1987 he was the president of the Swedish Mathematical Society. In 1998 he was awarded the Royal Society of Sciences in Uppsala's Celsius Gold Medal.
Jaak Peetre was the most prolific Estonian mathematician of his era, often visiting Estonia and giving lectures there. In 1994 he was a founding member of the Estonian Mathematical Society. In 2001 he was awarded the Order of the White Star, 3rd Class. In 2008 he was elected a foreign member of the Estonian Academy of Science.
Selected publications
Articles
(Over 900 citations)
Books
(See Edgar Krahn.)
References
Further reading
Eesti entsüklopeedia (Estonian Encyclopedia) 14, 364
Eesti teadlased väljaspool kodumaad: biograafiline teatmik (Estonian scholars and scientists abroad: biographical directory). Stockholm, 1984, 91
Eesti teaduse biograafiline leksikon. 3. köide: N–Sap TTEÜ, avaldatud elekrooniliselt 2013
1935 births
2019 deaths
Estonian mathematicians
Swedish mathematicians
Mathematical analysts
Partial differential equation theorists
Recipients of the Order of the White Star, 3rd Class
Lund University alumni
Academic staff of Lund University
Estonian emigrants to Sweden
Estonian World War II refugees
Scientists from Tallinn
Members of the Royal Swedish Academy of Sciences | Jaak Peetre | [
"Mathematics"
] | 681 | [
"Mathematical analysis",
"Mathematical analysts"
] |
68,038,337 | https://en.wikipedia.org/wiki/Sofpironium%20bromide | Sofpironium bromide, sold under the brand name Ecclock among others, is a medication used to treat hyperhidrosis (excessive sweating). Sofpironium bromide is an anticholinergic agent that is applied to the skin.
It was approved for medical use in Japan in 2020, and in the United States in June 2024.
Medical uses
Sofpironium bromide is indicated for the treatment of primary axillary hyperhidrosis.
Mechanism of action
The pharmacodynamics of sofpironium bromide are unknown.
Society and culture
Legal status
It was approved for medical use in Japan in November 2020, and in the United States in June 2024.
Brand names
Sofpironium bromide is the international nonproprietary name.
It is sold under the brand name Ecclock in Japan and under the brand name Sofdra in the US.
References
Further reading
External links
Dermatologic drugs
Muscarinic antagonists
Quaternary ammonium compounds
Bromides
Pyrrolidines
Tertiary alcohols
Carboxylate esters
Ethyl esters
Cyclopentyl compounds | Sofpironium bromide | [
"Chemistry"
] | 235 | [
"Bromides",
"Salts"
] |
68,038,362 | https://en.wikipedia.org/wiki/Qu%20Geping | Qu Geping is a Chinese environmental scientist. He was Director of the Chinese State Environmental Protection Agency from 1987 to June 1993.
In 1999, he was the winner of the Blue Planet Prize along with Paul R. Ehrlich.
In 2001, he was awarded the Duke of Edinburgh Conservation Medal, the highest award of the World Wildlife Fund, calling him the father of environmental protection in China.
References
Living people
Environmental scientists
Chinese earth scientists
Year of birth missing (living people) | Qu Geping | [
"Environmental_science"
] | 96 | [
"Environmental scientists"
] |
68,038,419 | https://en.wikipedia.org/wiki/Yael%20Nemirovsky | Yael Nemirovsky (born July 21, 1944) is an Israeli chemist and electrical engineer known for her research in microelectromechanical systems and microoptoelectromechanical systems. She is a professor emerita of electrical engineering at the Technion – Israel Institute of Technology.
Education and career
Nemirovsky was born on July 21, 1944, in Haifa, then part of Mandatory Palestine. She studied chemistry at the Technion, earning a bachelor's degree in 1966 and completing her Ph.D. in 1971. She became a research scientist at Rafael Advanced Defense Systems, also taking an adjunct lecturer position at the University of Haifa, where she began working in electrical engineering, on topics including surface acoustic wave devices and optoelectronics.
After working at Rafael from 1972 to 1980, she returned to academia in 1980, as a senior lecturer in electrical engineering at the Technion. She became an associate professor in 1985 and a full professor in 2011. She retired from the Technion as professor emerita in 2013, and from 2012 to 2015 headed the department of electrical engineering at Kinneret College.
She was the founder of BlueBird Optical MEMS Inc., its president from 2001 to 2002, and its chief scientist from 2002 to 2005. Since 2014 she has been chief scientist of TODOS Technologies Ltd., a spin-off from the Technion developing CMOS-based infrared sensors.
Recognition
Nemirovsky was named a Fellow of the IEEE in 1999, "for contributions to compound semiconductor devices and technology". She is also a Fellow of the Institution of Electrical Engineers.
References
External links
Home page
1944 births
Living people
Israeli chemists
Israeli women chemists
Israeli electrical engineers
Israeli women engineers
Technion – Israel Institute of Technology alumni
Academic staff of Technion – Israel Institute of Technology
Fellows of the IEEE
Fellows of the Institution of Engineering and Technology | Yael Nemirovsky | [
"Engineering"
] | 389 | [
"Institution of Engineering and Technology",
"Fellows of the Institution of Engineering and Technology"
] |
68,038,669 | https://en.wikipedia.org/wiki/Lorraine%20Whitmarsh | Lorraine Elisabeth Whitmarsh is a British psychologist and environmental scientist at the University of Bath. She serves as Director of the Centre for Climate Change and Social Transformations. Her research considers how the public engage with climate change, energy and transport.
Early life and education
Whitmarsh was an undergraduate student at the University of Kent, where she studied theology and religious studies. As a graduate student, Whitmarsh studied psychology at the University of Bath. Her doctoral research considered the public understanding of climate change in Southern England. She moved to the University of East Anglia as a research associate in 2005, where she spent four years.
Research and career
Whitmarsh joined the faculty at Cardiff University in 2009, where she was promoted to Professor in 2015. In 2014, Whitmarsh was awarded a European Research Council Starting Grant to investigate low carbon lifestyles. Whitmarsh was later awarded a European Research Council Consolidator Grant where she studied the moments that cause pro-environmental behaviour shifts.
Whitmarsh moved to the University of Bath in 2020, where she was made a Professor of Environmental Psychology. She leads the Centre for Climate Change and Social Transformation, which considers how society must adapt to reduce emissions. In particular, Whitmarsh has focussed on mobility, food, insulation and material consumption. Whitmarsh has argued that psychologists can effectively communicate the risks associated with climate change, as well as helping people to mitigate hyperthermia or natural disasters. She has worked with city councils to design interventions that encourage low-carbon travel, as well as supporting the roll-out of infrastructure changes such as cycle paths. Whitmarsh was involved with the UK Climate Assembly, a citizen science engagement process that looked to take public opinion on climate change to the Government of the United Kingdom.
Whitmarsh has contributed to the Intergovernmental Panel on Climate Change, and served as a lead author for the IPCC Working Group II. She serves on the advisory team of the parliamentary group for a green new deal.
Whitmarsh was appointed Member of the Order of the British Empire (MBE) in the 2022 New Year Honours for services to social research in climate change, energy and transport.
Selected publications
Books
References
British psychologists
Environmental scientists
Alumni of the University of Kent
Academics of the University of Bath
Alumni of the University of Bath
Year of birth missing (living people)
Living people
Members of the Order of the British Empire
British women psychologists
Environmental psychologists | Lorraine Whitmarsh | [
"Environmental_science"
] | 500 | [
"Environmental scientists",
"British environmental scientists"
] |
68,040,556 | https://en.wikipedia.org/wiki/List%20of%20features%20removed%20in%20Windows%2011 | Windows 11 is the latest major release of the Windows NT operating system and the successor of Windows 10. Some features of the operating system were removed in comparison to Windows 10, and further changes in older features have occurred within subsequent feature updates to Windows 11. Following is a list of these.
Features removed in original release
Bundled software
No longer available
The following applications are no longer bundled with Windows 11 and no longer available.
Internet Explorer
Wallet
Not bundled, but available
The following applications are no longer bundled with Windows 11, but can still be installed from the Microsoft Store.
3D Viewer
OneNote for Windows 10
Skype
Windows shell
The following parts of the Windows shell are no longer available in Windows 11.
Lock Screen's quick status
Toggleable tablet mode (now is automatically enabled on touch devices)
Timeline feature in Task View
Save Search option in File Explorer
In addition:
The touch keyboard no longer docks in screens larger than 18 inches.
Windows no longer synchronizes desktop wallpapers across devices with a Microsoft account.
Windows no longer shows a small preview of images or videos on folder thumbnails. Instead, it shows the generic folder icon for any folder containing images or videos.
Start menu
Some functionality from the Start menu was removed and replaced with other features.
Folders and groups
Live tiles, but the Widgets panel provides portions of what the live tiles of Windows 10's bundled apps provided
Recent and pinned files on pinned apps
Taskbar
The following taskbar features are no longer available as of Windows 11:
Support for moving the taskbar to the top, left, or right of the screen
Support for changing the size of the taskbar or its icons
"Time" is not displayed in the calendar when clicking on the "Date/Time" on taskbar
Scheduled events are not displayed in the calendar when opened
The option to show or hide Windows shell's tray icons (Only third-party icons can be hidden or shown)
All settings and shortcuts in the taskbar's context menu (Only a shortcut to the taskbar settings area of the Settings app is available.)
The network and audio flyouts have been consolidated into a new settings flyout
"Some icons in the System Tray", although Microsoft doesn't specify which
Support for third-party taskbar components (deskbands)
The upward swipe gesture for jumplists
Ability to move the system tray from the primary monitor
The People button (The "Chat" button powered by Microsoft Teams takes its place.)
The News and Interests panel (The "Widgets" panel serves the same purpose.)
Action Center (Two separate flyouts take its place: "Notification Center" and "Quick Settings")
Support for showing one icon per app window the taskbar (Reinstated in May 2023; option merged with showing labels)
Support for showing windows labels on taskbar (Reinstated in May 2023; option merged with separating window icons)
Support for bringing an app into focus by dragging a file to its button (Reinstated in February 2022 insider builds)
Task Manager can no longer be opened by right-clicking taskbar (Reinstated in September 2022 insider builds)
Ability to peek at the desktop by hovering the mouse cursor over the Show Desktop button
Ability to display the seconds on the current time removed (Reinstated in November 2022)
Support for adding toolbars such as the Quick Launch Bar (apart from 3rd party software)
Expanding Taskbar to two levels
Settings
File History can only be configured using the legacy Control Panel application, which does not support adding custom folders to the set of protected folders as the Settings app in Windows 10 did.
The option to simultaneously set a program as the default for all file associations it can handle is no longer available.
Architecture and other features
Windows 11 is only available for the x86-64 and ARM64 CPU architectures, as Microsoft is no longer offering a Windows build for IA-32 x86 and ARMv7 systems. Additionally, NTVDM and the 16-bit Windows on Windows subsystems, which allowed 32-bit versions of Windows to directly run 16-bit DOS and Windows programs, are no longer included with Windows 11.
User-mode scheduling (UMS), available on x64 versions Windows 7 and later, was a lightweight mechanism allowing applications to schedule their own threads, without involvement from the system scheduler. This feature is not included with Windows 11.
Themes
The default Windows 10 and Flowers themes have been removed.
Features removed in later releases
2022 Update
The Focus assist feature has been split to Focus and Do Not Disturb.
Attempting to run 32-bit apps on ARM64 systems that do not support 32-bit mode will now fail gracefully with an error rather than crash.
2023 Update
Microsoft Teams Chat icon on taskbar is removed.
2024 Update
WordPad is no longer bundled with Windows 11, but is still included in existing installations.
A x86-64-v2 CPU supporting SSE4.2 and POPCNT CPU instructions is now required.
An ARMv8.1 CPU is now required, dropping unofficial support for ARMv8.0.
WMI command line tool (WMIC) is no longer installed by default. It has been made as an optional feature installable via Windows Settings.
See also
Notes
References
Features Removed In
Software features
Microsoft lists
Computing-related lists | List of features removed in Windows 11 | [
"Technology"
] | 1,073 | [
"Computing-related lists",
"Microsoft lists",
"Software features"
] |
68,040,608 | https://en.wikipedia.org/wiki/Regenerative%20medicine%20advanced%20therapy | Regenerative Medicine Advanced Therapy (RMAT) is a designation given by the Food and Drug Administration to drug candidates intended to treat serious or life-threatening conditions under the 21st Century Cures Act. A RMAT designation allows for accelerated approval based surrogate or intermediate endpoints.
RMAT goes beyond breakthrough therapy features by allowing for accelerated approval of drugs based on surrogate endpoints. A surrogate endpoint is a biomarker that substitutes for a direct endpoint, such as clinical benefit.
Legal background
Section 3033 of the 21st Century Cures Act introduces section 506(g) of the Federal Food, Drug, and Cosmetic Act (FD&C Act) that allows for the designation of certain therapies as a 'regenerative medicine advanced therapy' (RMAT) ().
Qualifying criteria
In order to qualify for RMAT status, a treatment must
meet the definition of a regenerative medicine therapy,
intend to treat, modify, reverse or cure a serious condition, and
be supported by preliminary clinical evidence that indicates the RMAT candidate can address the clinical need.
A regenerative medicine therapy is defined in section 506(g)(8) of the FD&C Act to include cell therapies, therapeutic tissue engineering, human cell and tissue products. Under the FDA's interpretation, gene therapies and genetically modified cells that have a lasting effect, such as CAR-T antitumor therapies, may also qualify as regenerative medicine therapies.
Effect
A RMAT designation includes all benefits of the Fast Track and breakthrough therapy designations. In addition, it opens up early interactions between the FDA and sponsors to facilitate accelerated approval. In this context, accelerated approval means approval based on
previously agreed-upon surrogate or intermediate endpoints, or
data from a limited but meaningful number of sites.
The ability to use 'Real World Evidence' (RWE), i.e. post-market evidence of safety and effectiveness, is particularly useful in the context of orphan diseases, where recruiting a sufficiently large cohort for pre-marketing clinical trials may not be feasible. RWE may include data from patient registries, clinical records and case studies.
Where a RMAT's sponsor fails to comply with the requirements for accelerated approval, the RMAT designation and the benefits conferred by it can be withdrawn ().
Examples
Statistics
In 2020, the FDA received 34 requests for RMAT status, of which 12 (35.3%) were granted. RMAT designated drugs include the novel CAR-T therapy Kymriah and betibeglogene autotemcel for beta thalassemia. As of 31 March 2021, 62 requests for RMAT status have been granted.
More than half of the RMAT applications received by March 2019 involved autologous or allogeneic cell therapy products, including CAR-T therapies.
See also
Breakthrough therapy
Advanced Therapy Medicinal Product (European Medicines Agency equivalent)
Sakigake (Japanese equivalent)
Orphan drug
References
Pharmacy
Pharmaceuticals policy
Food and Drug Administration | Regenerative medicine advanced therapy | [
"Chemistry"
] | 618 | [
"Pharmacology",
"Pharmacy"
] |
68,040,716 | https://en.wikipedia.org/wiki/Features%20new%20to%20Windows%2011 | Windows 11 is the current major release of Microsoft's Windows NT operating system. Released on October 5, 2021, Windows 11 succeeds the previous major release, Windows 10.
Major updates introduced with the product include a redesigned user interface, new productivity and collaboration features, and updates to security and accessibility.
As a current release, the operating system receives annual feature enhancements, such as the addition of artificial intelligence features like Microsoft Copilot which launched in 2023.
Windows Shell
Fluent Design System: Updates the Fluent Design System, a design language introduced by Microsoft in 2017, are featured in Windows 11. According to Microsoft, the design of Windows 11 is "effortless, calm, personal, familiar, complete, and coherent." The redesign focuses on simplicity, ease of use, and flexibility, addressing some of the deficiencies of Windows 10. Most interfaces in Windows 11 feature rounded geometry, refreshed iconography, new typography, and a refreshed color palette. In addition, translucency and shadows are made more prevalent throughout the system. Windows 11 also introduces "Mica", a new opaque Material that is tinted with the color of the desktop wallpaper.
Start Menu: The Start menu has been significantly redesigned in Windows 11, adhering to the principles of the updated Fluent Design System. The menu has now been moved to the center by default, with an option to move it back to the left side. The Live Tiles feature introduced in Windows 8 is replaced by a set of pinned apps and a new cloud-powered "Recommended" section that shows recently opened files and documents from any location, including a PC, a smartphone, and OneDrive. The new Start menu also includes a search box.
Taskbar: The Taskbar has also been center-aligned, and now includes new animations for pinning, rearranging, minimizing, and switching apps on the Taskbar. The buttons can still be moved to the left-hand corner as in Windows 10.
Notification Center & Quick Settings: The Action Center from Windows 10 has been replaced by a Notification Center and a Quick Settings menu, both accessible from the lower-right corner of the Taskbar. The Notification Center contains all the user's notifications and a full-month calendar, while the Quick Settings menu lets the user manage common PC settings quickly and easily like Volume, Brightness, Wi-Fi, Bluetooth, and Focus Assist. Directly above the Quick Settings menu, the user can see media playback information when watching a video on platforms such as YouTube, or when listening to music in apps like Spotify.
File Explorer: The File Explorer on Windows 11 has been refreshed with the Fluent Design System and the Ribbon interface has been replaced with a new command bar with a revamped user interface and a Mica background. It also introduces revamped context menus with rounded corners, larger text, and Acrylic. App developers will also be able to extend the new context menus.
Themes: In addition to new default themes on Windows 11 for both Light and Dark mode, it also includes four new additional themes. Windows 11 also adds new high-contrast themes for people with visual impairments.
Sounds: Windows 11 introduces a new set of system sounds. The sounds are slightly different depending on whether the theme is set to light or dark mode. In addition, a new Windows startup sound replaces the one used since Windows Vista.
Widgets: Windows 11 adds a new taskbar flyout named "Widgets", which displays a panel with Microsoft Start, a news aggregator with personalized stories and content (expanding upon the "news and interests" panel introduced in later builds of Windows 10). The user can customize the panel by adding or removing widgets, rearranging, resizing, and personalizing the content.
User interface (UI) improvements
Windows 11 updates several system dialog boxes such as the alert for when the battery is running low.
The taskbar previews have been updated to reflect Windows 11's new visual design.
The hidden icons flyout on the lower-right corner of the taskbar has also been redesigned to match Windows 11's visuals.
Multitasking
Snap Layouts: Users can now hover over a window's maximize button to view available snap layouts, and then click a zone to snap the window. They will then be guided to snap windows to the rest of the zones within the layout using a guided snap assist. There is a set of four available snap layouts on smaller screens.
Snap Groups: Snap groups are a way to easily switch back to a set of snapped windows, which are stored in the grouped app's taskbar icons.
Virtual Desktops: Virtual desktops can be accessed via the Task View feature on the Taskbar. Users can reorder and customize the background for each of their desktops. They can also hover over the Task View button on the Taskbar to quickly access their desktops or to create a new one.
Docking: When the user undocks a laptop, the windows on the monitor will be minimized, and when the laptop is redocked to a monitor, Windows will put everything where it was before.
Input
Touch Keyboard: Windows 11 introduces thirteen new themes to customize the touch keyboard, including 3 hardware-matching themes that match the Surface keyboard colors. It also adds a new theme engine that allows the user to create a custom theme using background images. In addition, Windows 11 adds the ability to resize the touch keyboard.
Voice Typing: Windows 11 includes a new voice typing launcher to easily start voice typing in a selected field. It is turned off by default, but it can be turned on in Settings and placed in any area of the screen.
Touch Improvements: Windows 11 also features an improvement to touch-based interactions. Tablet mode is removed; instead, Windows will automatically adapt when needed. New and improved gestures can be used on tablets and touchscreens. App windows now have larger touch targets and will automatically arrange themselves in split view when the screen is rotated. Windows 11 seems to be optimized for desktops and tablets without combining the two like Windows 8 and Windows 10 did.
Pen Menu: For digital pen users, a new pen menu has been added, which is accessible by clicking the pen icon on the taskbar. By default, it contains two apps that can be customized by clicking the gear icon and selecting "Edit pen menu". In the flyout, users can add up to four of their favorite drawing or writing apps to the pen menu to open them quickly when using a pen.
Language and Input Switcher: A switcher that will show up next to the Quick Settings menu allows the user to switch languages and keyboard layouts. Users can press the Windows + Spacebar keyboard shortcut to toggle between input methods.
Display improvements
Dynamic refresh rate automatically increases the refresh rate when scrolling or when using the inking function in some applications. It can also lower the refresh rate, when possible, to save battery power.
Auto HDR.
Content adaptive brightness control (CABC).
HDR support to color-managed apps.
HDR certification.
DirectStorage: Originally introduced with the Xbox Series X and Series S, it requires a graphics card supporting DirectX 12 Ultimate, and an NVMe solid-state drive.
Hardware support
Supports WPA3.
Supports NVMe 2.0.
Since Windows 11, Device Manager supports to view and manage installed drivers with click "View - Drivers".
Windows Subsystem for Android (WSA)
Windows 11 allows users to install and run Android apps on their devices using the new Windows Subsystem for Android (WSA) and the Android Open Source Project (AOSP). This runs with Intel Bridge Technology, a runtime post-compiler that enables apps written for other architectures to run on x86. These apps can be obtained from the Microsoft Store via the Amazon Appstore, or through other sources.
On March 5, 2024, Microsoft announced the termination of this feature in the updated support document of WSA: "As a result, the Amazon Appstore on Windows and all applications and games dependent on WSA will no longer be supported beginning March 5, 2025. Until then, technical support will remain available to customers".
Windows 11 on Arm
In Windows 11 on Arm, CHPE is replaced by ARM64EC (Emulation Compatible), a superset of ARM64 which combines ARM64 and x86 code (32-bit and 64-bit), allowing apps to be incrementally transitioned from emulated to native. Arm64X binaries were also introduced to support classic Arm64 code and Arm64EC code together. Windows 11 added support for OpenCL 1.2 via CLon12 and OpenGL 3.3 via GLon12, open source OpenCL and OpenGL implementations on top DirectX 12 via Mesa Gallium. Version 22H2 updated the .NET Framework adding native ARM64 support. Version 23H2 added support for vTPM in Hyper-V.
Bundled software
Microsoft Store, which serves as a unified storefront for apps and other content, is also redesigned in Windows 11. Microsoft now allows developers to distribute Windows API, progressive web applications, and other packaging technologies in the Microsoft Store, alongside the standard Universal Windows Platform apps. The new Microsoft Store will also enable users to install Android apps onto their devices via the Amazon Appstore. This feature will require a Microsoft account, an Amazon account, and a one-time install for Windows Amazon Appstore client.
Microsoft Teams: This collaboration platform is directly integrated into Windows 11. Skype is no longer bundled with the OS. Teams will appear as an icon in the Windows taskbar, letting users message and call their contacts instantly.
Settings: The app has been redesigned to be visually pleasing and easy to use in Windows 11. It has a left-handed navigation that persists between pages, and it adds breadcrumbs as the user navigates deeper into the settings to help them know where they are and to not get lost. The Settings app also includes brand new pages, with new controls at the top that highlight key information and frequently used settings for the user to adjust to their content. These new controls span across several category pages like System, Bluetooth & devices, Personalization, Accounts and Windows Update. It also adds expandable boxes for pages with many settings.
Snipping Tool: In Windows 11, both the legacy Snipping Tool and newer Snip & Sketch apps have been replaced by a new Snipping Tool app with the combined functionality of both apps. It includes a new user interface similar to the legacy Snipping Tool with extra features like the Windows + Shift + S keyboard shortcut from Snip & Sketch and richer editing. Windows 11 also introduces a new Settings page for the Snipping Tool. In addition, the new Snipping Tool adds support for dark mode.
Calculator: Like the Snipping Tool, Calculator includes a new app theme setting. The Calculator has been completely rewritten in C# and includes several new features.
Mail and Calendar: These apps have been updated with a new visual style. They include rounded corners and other adjustments to make them look and feel more inclusive on Windows 11.
Photos: The Photos app has been updated with a new viewing experience, editing features, Fluent Design, WinUI controls, rounded corners, and more. Photos app, which would be set up as the default image viewer in Windows 11, will allow users to explore collections, albums, and folders. The Collection feature remains unchanged, and it will show the most recent photos and screenshots, organized in proper order by date. Albums are also generated automatically using Microsoft's UI technology, but users can always customize the experience with their own albums. The Photos app also introduces a floating menu with new editing controls and will let users compare up to four pictures at once.
Tips: Windows 11 introduces a refreshed Tips app with a new look and additional UI updates. It comes with over 100 new tips to get started with Windows 11 or to learn new things.
Paint: One of the oldest Windows apps, which remained unchanged since Windows 7, has been given an updated user interface with rounded corners and the Mica material for Windows 11. The most prominent change to Paint is a new simplified toolbar, a rounded color palette, and a new set of drop-down menus. AI features have also been introduced, including background removal and an ability to generate images from text descriptions using DALL-E technology.
Notepad and Voice Recorder also feature refreshed interfaces. These apps now feature designs adhering to the Fluent Design principles.
The Microsoft Office apps have been redesigned to align with Fluent Design.
Windows 11 also features a new Media Player app, which acts as a replacement for Windows 10's Groove Music app.
Xbox app: An updated Xbox app is bundled with Windows 11. Features such as Xbox Cloud Gaming and Xbox Game Pass are integrated directly into the app.
Security and performance
Microsoft promoted performance improvements such as smaller update sizes, faster web browsing in "any browser", faster wake time from sleep mode, and faster Windows Hello authentication.
As part of the minimum system requirements, Windows 11 only officially supports devices with a Trusted Platform Module 2.0 security coprocessor. According to Microsoft, TPM 2.0 is a "critical building block" for protection against firmware and hardware attacks. In addition, Microsoft now requires devices with Windows 11 to include Virtualization-Based Security (VBS), Hypervisor-Protected Code Integrity (HVCI), and Secure Boot built-in and enabled by default. The operating system also features hardware-enforced stack protection for supported Intel and AMD processors for protection against zero-day exploits. Windows 11 Home SKUs require an Internet connection and a Microsoft account for first-time setup.
See also
References
Windows 11
Software features
Microsoft lists
Computing-related lists | Features new to Windows 11 | [
"Technology"
] | 2,849 | [
"Computing-related lists",
"Microsoft lists",
"Software features"
] |
68,041,656 | https://en.wikipedia.org/wiki/Global%20Commission%20on%20the%20Stability%20of%20Cyberspace | The Global Commission on the Stability of Cyberspace was a multistakeholder Internet governance organization, dedicated to the creation of diplomatic norms of governmental non-aggression in cyberspace. It operated for three years, from 2017 through 2019, and produced the diplomatic norm for which it was chartered and seven others.
Origins
Together with the Global Forum on Cyber Expertise, the GCSC was a product of the 2015-2017 Dutch chairmanship of the London Process, and particularly the work of Wouter Jurgens who, as head of the cyber security department of the Dutch Ministry of Foreign Affairs, had responsibility for organizing the 4th Global Conference on CyberSpace ministerial, which was held in The Hague April 16–17 of 2015, and formalizing its outcomes. Jurgens had been working for several years on the topic of governmental non-aggression in cyberspace, in collaboration with Uri Rosenthal, Bill Woodcock, Olaf Kolkman, James Lewis, and others who would subsequently become GCSC commissioners.
The GCSC was launched by Dutch Foreign Minister Bert Koenders at the 53rd Munich Security Conference, on February 18, 2017, with a three-year charter, and issued its final report at the Paris Peace Forum, on November 13, 2019.
Published norms
Norm to Protect the Public Core of the Internet
The Norm to Protect the Public Core is the GCSC's principal product, and has been included or referenced in many subsequent legislative and diplomatic work. It was included in the European Union's Cybersecurity Act, which extends the mandate of the European Union Agency for Cybersecurity to include the protection of the public core. The Paris Call for Trust and Security in Cyberspace included a call for compliance with the Public Core norm. The United Nations cites the Public Core norm in the 2019 report of the Secretary General and the report of the Secretary General’s High-level Panel on Digital Cooperation, The Age of Digital Interdependence.
Norm to Protect the Electoral Infrastructure
Norm to Avoid Tampering
Norm Against Commandeering of ICT Devices into Botnets
Norm for States to Create a Vulnerabilities Equities Process
Norm to Reduce and Mitigate Significant Vulnerabilities
Norm on Basic Cyber Hygiene as Foundation Defense
Norm Against Offensive Cyber Operations by Non-State Actors
Other publications
In addition to the Norm to Protect the Public Core and the seven subsequent norms, the GCSC has published several other documents.
Definition of the Public Core, to which the Norm Applies
Early in the process of defining the Norm to Protect the Public Core the effort was divided into two working groups, one, principally diplomatic, to specify what actions should be precluded; the other, involving subject-matter experts, to specify which infrastructures were deemed most worthy of protection. This latter working group specified a survey of cybersecurity experts, delegated implementation of the survey to Packet Clearing House, and integrated its results to form the Definition of the Public Core, to which the Norm Applies. This definition of the "public core of the Internet" to include packet routing and forwarding, naming and numbering systems, the cryptographic mechanisms of security and identity, and physical transmission media, with more-specific details attending to each, has since been used by the OECD and others as a standardized description of the principal elements of Internet critical infrastructure.
Statement on the Interpretation of the Norm on Non-Interference with the Public Core
On September 22, 2021, the GCSC released a three-page statement responding, in large part, to Russia's submission to the ITU Council Working Group on International Internet-related Public Policy Issues, Risk Analysis of the Existing Internet Governance and Operational Model. The statement reiterates the GCSC's findings that state actors are the primary threat to Internet stability, not private actors; that the GCSC believes that the multistakeholder model of Internet governance is key to maintaining Internet stability, and that the Internet's critical infrastructure is principally operated by the private sector.
Derivative work
In addition to the norms the commission published, several other organizations were created and efforts undertaken as byproducts of the commission's work.
CyberPeace Institute
One of the most notable derivative outcomes of the GCSC's work was the formation of the CyberPeace Institute, headed by GCSC commissioner Marietje Schaake and Europol veteran Stéphane Duguin. This independent, non governmental organization has the mission to highlight the human aspect of cyberattacks. It works in close collaboration with relevant partners to reduce the harms from cyberattacks on people’s lives worldwide. The Institute builds on the GCSC's work by monitoring compliance with its norms and coordinating cyber-attack forensic and analytic efforts that broaden public understanding of norm violations.
Critical infrastructure assessment
As input to the Definition of the Public Core, a global survey of Internet infrastructure security experts was conducted in 2017 by Packet Clearing House, headed by GCSC commissioner Bill Woodcock.
Participants
Commissioners
Marina Kaljurand (Co-chair 2017-2018)
Latha Reddy (Co-chair 2017-2019)
Michael Chertoff (Co-chair 2019)
Motohiro Tsuchiya
Joseph Nye
Christopher Painter
Ilya Sachkov
Jeff Moss
Khoo Boon Hui
Anriette Esterhuysen
Xiadong Lee
Abdul-Hakeem Ajijola
Virgilio Almeida
Marietje Schaake
Bill Woodcock
Wolfgang Kleinwächter
Scott Charney
Elina Noor
Isaac Ben-Israel
Jonathan Zittrain
Nigel Inkster
Jane Holl Lute
Samir Saran
Olaf Kolkman
Former commissioners
William Saito
Wolff Heintschel von Heinegg
Sigrid Kaag
Hugo Zylerberg
Research Advisory Group
Sean Kanuck (Chair)
Liis Vihul (Deputy Chair for Law)
Marilia Maciel (Deputy Chair for Internet Governance)
Hugo Zylberberg (Deputy Chair for International Peace & Security)
Koichiro Komiyama (Deputy Chair for Technical and Information Security)
Secretariat
Bruce McConnell (EastWest Institute)
Alexander Klimburg (Hague Centre for Strategic Studies)
References
External links
Official web site of the Commission
Final report of the Commission
Definition of the "Public Core" of the Internet
Report of the GCSC Critical Infrastructure Assessment Working Group
Global policy organizations
International organisations based in the Netherlands
Internet governance
Internet governance organizations
Internet law
Internet security
Internet-related organizations
Internet ethics | Global Commission on the Stability of Cyberspace | [
"Technology"
] | 1,294 | [
"Internet ethics",
"Ethics of science and technology"
] |
68,042,075 | https://en.wikipedia.org/wiki/Yttrium%20oxalate | Yttrium oxalate is an inorganic compound, a salt of yttrium and oxalic acid with the chemical formula Y(CO). The compound does not dissolve in water and forms crystalline hydrates—colorless crystals.
Synthesis
Precipitation of soluble yttrium salts with oxalic acid:
Properties
Yttrium oxalate is highly insoluble in water and converts to the oxide when heated. Yttrium oxalate forms crystalline hydrates (colorless crystals) with the formula Y(CO)•n HO, where n = 4, 9, and 10.
Decomposes when heated:
The solubility product of yttrium oxalate at 25 °C is 5.1 × 10−30.
The trihydrate Y(CO)•3HO is formed by heating more hydrated varieties at 110 °C.
Y(CO)•2HO, which is formed by heating the decahydrate at 210 °C) forms monoclinic crystals with unit cell dimensions a=9.3811 Å, b=11.638 Å, c=5.9726 Å, β=96.079°.
Related
Several yttrium oxalate double salts are known containing additional cations. Also a mixed-anion compound with carbonate is known.
References
Inorganic compounds
Yttrium compounds
Oxalates | Yttrium oxalate | [
"Chemistry"
] | 278 | [
"Inorganic compounds"
] |
68,044,793 | https://en.wikipedia.org/wiki/Cobham%27s%20theorem | Cobham's theorem is a theorem in combinatorics on words that has important connections with number theory, notably transcendental numbers, and automata theory. Informally, the theorem gives the condition for the members of a set S of natural numbers written in bases b1 and base b2 to be recognised by finite automata. Specifically, consider bases b1 and b2 such that they are not powers of the same integer. Cobham's theorem states that S written in bases b1 and b2 is recognised by finite automata if and only if S differs by a finite set from a finite union of arithmetic progressions. The theorem was proved by Alan Cobham in 1969 and has since given rise to many extensions and generalisations.
Definitions
Let be an integer. The representation of a natural number in base is the sequence of digits such that
where and . The word is often denoted , or more simply, .
A set of natural numbers S is recognisable in base or more simply -recognisable or -automatic if the set of the representations of its elements in base is a language recognisable by a finite automaton on the alphabet .
Two positive integers and are multiplicatively independent if there are no non-negative integers and such that . For example, 2 and 3 are multiplicatively independent, but 8 and 16 are not since . Two integers are multiplicatively dependent if and only if they are powers of a same third integer.
Problem statements
Original problem statement
More equivalent statements of the theorem have been given. The original version by Cobham is the following: Another way to state the theorem is by using automatic sequences. Cobham himself calls them "uniform tag sequences.". The following form is found in Allouche and Shallit's book:We can show that the characteristic sequence of a set of natural numbers S recognisable by finite automata in base k is a k-automatic sequence and that conversely, for all k-automatic sequences and all integers , the set of natural numbers such that is recognisable in base .
Formulation in logic
Cobham's theorem can be formulated in first-order logic using a theorem proven by Büchi in 1960. This formulation in logic allows for extensions and generalisations. The logical expression uses the theory
of natural integers equipped with addition and the function defined by and for any positive integer , if is the largest power of that divides . For example, , and .
A set of integers is definable in first-order logic in if it can be described by a first-order formula with equality, addition, and .
Examples:
The set of odd numbers is definable (without ) by the formula
The set of the powers of 2 is definable by the simple formula .
We can push the analogy with logic further by noting that S is first-order definable in Presburger arithmetic if and only if it is ultimately periodic. So, a set S is definable in the logics and if and only if it is definable in Presburger arithmetic.
Generalisations
Approach by morphisms
An automatic sequence is a particular morphic word, whose morphism is uniform, meaning that the length of the images generated by the morphism for each letter of its input alphabet is the same. A set of integers is hence k-recognisable if and only if its characteristic sequence is generated by a uniform morphism followed by a coding, where a coding is a morphism that maps each letter of the input alphabet to a letter of the output alphabet. For example, the characteristic sequence of the powers of 2 is produced by the 2-uniform morphism (meaning each letter is mapped to a word of length 2) over the alphabet defined by
which generates the infinite word
,
followed by the coding (that is, letter to letter) that maps to and leaves and unchanged, giving
.
The notion has been extended as follows: a morphic word is -substitutive for a certain number if when written in the form
where the morphism , prolongable in , has the following properties:
all letters of occur in , and
is the dominant eigenvalue of the matrix of morphism , namely, the matrix , where is the number of occurrences of the letter in the word .
A set S of natural numbers is -recognisable if its characteristic sequence is -substitutive.
A last definition: a Perron number is an algebraic number such that all its conjugates belong to the disc . These are exactly the dominant eigenvalues of the primitive matrices of positive integers.
We then have the following statement:
Logic approach
The logic equivalent permits to consider more general situations: the automatic sequences over the natural numbers or recognisable sets have been extended to the integers , to the Cartesian products , to the real numbers and to the Cartesian products .
Extension to
We code the base integers by prepending to the representation of a positive integer the digit , and by representing negative integers by followed by the number's -complement. For example, in base 2, the integer is represented as . The powers of 2 are written as , and their negatives (since is the representation of ).
Extension to
A subset of is recognisable in base if the elements of , written as vectors with components, are recognisable over the resulting alphabet.
For example, in base 2, we have and ; the vector is written as .An elegant proof of this theorem is given by Muchnik in 1991 by induction on .
Other extensions have been given to the real numbers and vectors of real numbers.
Proofs
Samuel Eilenberg announced the theorem without proof in his book; he says "The proof is correct, long, and hard. It is a challenge to find a more reasonable proof of this fine theorem." Georges Hansel proposed a more simple proof, published in the not-easily accessible proceedings of a conference. The proof of Dominique Perrin and that of Allouche and Shallit's book contains the same error in one of the lemmas, mentioned in the list of errata of the book. This error was uncovered in a note by Tomi Kärki, and corrected by Michel Rigo and Laurent Waxweiler. This part of the proof has been recently written.
In January 2018, Thijmen J. P. Krebs announced, on Arxiv, a simplified proof of the original theorem, based on Dirichlet's approximation criterion instead of that of Kronecker; the article appeared in 2021. The employed method has been refined and used by Mol, Rampersad, Shallit and Stipulanti.
Notes and references
Bibliography
Combinatorics
Number theory
Theoretical computer science
Finite automata
Information theory
Combinatorics on words | Cobham's theorem | [
"Mathematics",
"Technology",
"Engineering"
] | 1,394 | [
"Discrete mathematics",
"Theorems in combinatorics",
"Telecommunications engineering",
"Theoretical computer science",
"Applied mathematics",
"Combinatorics",
"Theorems in discrete mathematics",
"Computer science",
"Information theory",
"Combinatorics on words",
"Number theory"
] |
72,428,594 | https://en.wikipedia.org/wiki/Gems%20of%20the%20Galaxy%20Zoos | Gems of the Galaxy Zoos (Zoogems) was a gap-filler project which used the Hubble Space Telescope to take images of unusual objects found by volunteers classifying data from both Galaxy Zoo (GZ) and Radio Galaxy Zoo (RGZ). Between the HSTs' main observations, there is a short time that objects within that field of view can be imaged using gaps which last approximately 12 - 25 mins. The Zoogems project sought to use those small observation gaps to image 300 candidates taken from the two Zoos in order to better study and comprehend them. Starting observations in May 2018, HST Proposal 15445 had by the end of September 2023 imaged 193 of the 300 candidates with many of them having near 11 minute exposures.
Background
GZ is a crowdsourced astronomy project which invites people to assist in the morphological classification of a large number of galaxies. Initially, many of the objects now being imaged were posted on the GZ forum and Talk pages from Summer 2007 through various versions until 2017.
The project Radio Galaxy Zoo started in December 2013, seeking to locate supermassive black holes. The science team wanted to identify black hole/jet pairs and associate them with their host galaxies. As a result of citizens' classifications, many unusual candidates visible in radio frequencies were flagged for further studies.
Through public analysis of more than 900,000 objects, volunteers collected a "menagerie of weird and wonderful galaxies" which few had seen before. The original proposal estimated that there were 1100 targets available, yet only 300 observation slots, so the public were asked to vote for which targets should be in the final list. Voting took place in February 2018 in order to meet the proposal's deadline of 28 February.
Project lead Dr. William Keel said in an interview on the University of Alabama site that Zoogems addressed a range of studies and that this happens rarely with galaxies. He explained that after volunteers had sifted through the images of a million galaxies, they had found examples of oddities and rarities. Further, by using data from HST, these objects that would not normally merit an individual project, put together would form an interesting study. Whenever a 20-minute gap in the HST schedule appears, software will go to the list of objects and see which is closest.
Observation setup
As with all HST gap-filler observations, the Wide-Field Camera mode of the Advanced Camera for Surveys is used for its larger field-of-view. The total exposure time of 674 seconds is made by a pair of two 337 second exposures, the same for all the gap-filler observations. Which of the following three filters is used depends on the target: i) the bluer F475W (roughly SDSS g) is used for mostly spiral structures, ii) the F814W for bulges and iii) the F625W which is closely matched with SDSS r filter. A range of software is used to calculate where the target's image is captured on the available ACS CCDs, using a coordinate offset within a 'circle of interest' to find the most useful coverage. A different strategy for Green Pea systems uses a choice of four filters allotted using distance values so as to study the continuum structure.
Green Pea galaxies
Among the 300 Zoogems, there are 74 candidates that are Pea galaxies. The first Zoogems study to be published in May 2021 was "An Old Stellar Population or Diffuse Nebular Continuum Emission Discovered in Green Pea Galaxies" which concentrated on 9 of them. In this study, Leonardo Clarke et al. examine the content of PGs to find out about the different ages of the stars and find that while the central star-forming clusters were up to 500 million years old, there are stars, possibly the host galaxy stars, which are older and are thought to be more than 1 billion years old.
Pea galaxies have been studied as they are the only population that has hydrogen-ionizing radiation escaping in large amounts. Because of this, they are seen as analogs of the galaxies that reionized the universe at the earliest times. Yet the substantial presence of old stars would not have been possible at the earliest stages of the first galaxies. The mix of old and new stars within Pea galaxies could create different gravitational conditions which might influence galactic winds and element retention. These conclusions imply that Pea galaxies are not real analogs of the galaxies responsible for the Epoch of Reionisation.
Double-lobed radio-loud AGNs
The first study detailing objects from Radio Galaxy Zoo was published by the Astrophysical Journal in December 2022. "An Elusive Population of Massive Disk Galaxies Hosting Double-lobed Radio-loud AGNs" seeks to answer whether the galaxy morphology of radio-loud Active Galactic Nucleii and its hosts are solely ellipticals ("early-type"), or that some are spirals ("late type"). Using images taken as part of Zoogems, they analyse a sample of radio galaxies which have extended double-lobed structures and see whether they can be associated with their disk-like optical objects. They find 18 galaxies that can be identified as spiral that are likely to have genuine associations between the radio and optical counterparts.
Zihao et al. assess whether these are chance alignments or that a host is too faint to be detected using probability statistics. This gave rise to the two confidence divisions of 'high' or 'low' with 18 having a high confidence and 14 a low confidence from the initial 32 galaxies. Because of the high-resolution Zoogems images and the visibility of disk-like structures, the team find that galaxy morphology can no longer be a unique signpost of a galaxy's ability to generate large-scale radio jets.
Unearthing galactic gems
In October 2023, the magazine Sky and Telescope featured an article entitled "Unearthing galactic gems". In it, the science journalist Madison Goldberg summarises the project and talks to Tom Brown from the Space Telescope Science Institute about the process of gap-fillers. Spare Hubble time had been used before with the 45 minute "snapshot programs" but some unscheduled time remained. Brown said: "It just seemed like a waste to be throwing that time on the floor. Just a handful of minutes here and there, but still, it adds up." And so, the gap-filler project started using those small gaps in the timetable to take 11 minute exposures.
Bill Keel, project lead scientist, explained that unusual galaxies can help us understand the universe today. He described the ZooGems category of 'overlapping galaxy pairs'. He said: "What’s unusual there is not the galaxies themselves, but the fact that one sits neatly behind the other in telescopic images." Samantha Brunker, a scientist studying Green Pea galaxies, said that the variety of unusual targets included in ZooGems is special. "If you’re going to paint a whole picture, you can’t leave out the weird things."
Various objects
NGC 1175, nicknamed the 'Peanut galaxy' is a barred spiral galaxy, approximately 252 million light years away. This has a peculiar morphology with the inner regions being thicker in some than in others, which has caused a 'boxy' appearance reminding the astronomers of an unshelled peanut.
NGC 2292 and NGC 2293 are two ellipticals, nicknamed the 'Greater Pumpkin', that have merged at about 120 million light years away. These interacting galaxies will eventually become a giant spiral, an event rare enough that there are only a few other examples in the Universe.
The VV-689 system, nicknamed the 'Angel Wing', is two galaxies merging. This interaction has left the resulting collision almost completely symmetrical (top of article).
The HST image of CGCG 396-2 shows an uncommon multi-armed merger 520 million light years from earth.
Two spiral galaxies, SDSS J115331 and LEDA 2073461, over a billion light years away, appear to be colliding. The effect caused by line-of-sight is likely by chance as the two are not actually interacting (image right hand side).
See also
Citizen Science
Cosmic dust
Irregular galaxy
Virtual volunteering
Zooniverse
References
External links
The Zoogems website
Amateur astronomy
Astronomy projects
Black holes
Citizen science
Galaxies
Hubble Space Telescope images | Gems of the Galaxy Zoos | [
"Physics",
"Astronomy"
] | 1,709 | [
"Black holes",
"Physical phenomena",
"Physical quantities",
"Galaxies",
"Unsolved problems in physics",
"Astrophysics",
"Density",
"Astronomy projects",
"Stellar phenomena",
"Astronomical objects"
] |
72,429,750 | https://en.wikipedia.org/wiki/Laura%20I.%20Gomez | Laura I. Gómez is a computer scientist known for establishing Atipca, a company that presents bias free names in recruiting.
Early life and education
Gómez was born in León Guanajuato, México and then moved to California when she was eight years old. Gomez got her first software engineering internship at the age of seventeen, when she got an internship working at Hewlett-Packard after she received a work permit. For college, she earned a Bachelor of Human Development and Family Studies from University of California Berkeley and a Master of Latin American Studies from University of California San Diego.
Career
Gomez worked with several start-ups and big technology companies, including YouTube, Google, and Twitter. She was one of the early employees at Twitter, and her work there centered on bringing Spanish into the user interface. Gomez has also discussed the use of social media as a means to practice as people learn a new language.
Gomez was a founding member of a project known as Project Include, a non-profit led by Ellen Pao that advocates for inclusion in the technology field. Project Interlude funded Gomez's start-up, Atipica, an organization which provides artificial and human intelligence to sort job candidates in a manner that reduces bias. Over time, Atipica was backed by Kapor Capital, Precursor Ventures, and True Ventures. One of the perks provided by Atipica is paid time off for employees supporting a political cause. The funding Gomez raised for Atipca was the largest financing level for a Latinx founder in Silicon Valley. As of 2023, Gomez was working on Proyecto Solace, a mental health initiative for Latinx peoples.
Awards and honors
Gomez was recognized by the Department of State and Former Secretary of State, Hillary Clinton, for her work in the TechWomen Program.
References
Living people
Computer scientists
University of California, Berkeley alumni
University of California, San Diego alumni
Year of birth missing (living people) | Laura I. Gomez | [
"Technology"
] | 391 | [
"Computer science",
"Computer scientists"
] |
72,430,652 | https://en.wikipedia.org/wiki/Novosibirsk%20Institute%20of%20Program%20Systems | Novosibirsk Institute of Program Systems () is a scientific organization in Sovetsky District of Novosibirsk, Russia. It was founded in 1972.
History
In 1972, a branch of the Lebedev Institute of Precision Mechanics and Computer Engineering was established in Novosibirsk. In 1992, the branch became an independent organization. In 2002, 240 people worked at the institute.
Activity
The organizstion is engaged in the development of automated control systems. It created automated control systems for the Diamonds of Russia – Sakha, Surgut-1 Power Station etc.
References
Research institutes in Novosibirsk
1972 establishments in the Soviet Union
Research institutes established in 1972
Automation organizations | Novosibirsk Institute of Program Systems | [
"Engineering"
] | 140 | [
"Automation organizations",
"Automation"
] |
72,430,683 | https://en.wikipedia.org/wiki/Main-group%20element-mediated%20activation%20of%20dinitrogen | Main-group element-mediated activation of dinitrogen is the N2 activation facilitated by reactive main group element centered molecules (e.g., low valent main group metal calcium, dicoordinate borylene, boron radical, carbene, etc.).
Background
Dinitrogen fixation is essential for human life. Currently, the industry uses the Haber–Bosch process to convert N2 and H2 to NH3 based on the metal catalysis under very high pressure and temperature conditions. Alternative strategies that realize the transformation from N2 to NH3 under mild conditions are a long-lasting goal in chemistry. In the past decades, a number of transition-metal species have been found to bind (and even functionalize) N2. The prevalence of transition metals in dinitrogen activation is attributed to the fact that the unoccupied and occupied d orbitals could be both energetically and symmetrically accessible to accept electron density from and back donate to N2. Nevertheless, the development of low-valent, low-coordinate main-group elements which mimic the electronic properties of transition metal provides more opportunities to unearth the N2 activation by main group elements.
Lithium can also react with N2 at room temperature to give an isolable product Li3N. However, it was until recently that the controllable, stepwise N2 activation by main group element began to thrive, especially for those whose key intermediates were well structurally characterized and even isolated.
N2 activation by calcium
In 2021, Harder et al. achieved dinitrogen activation by a low-valent calcium complex, which was generated by the reduction of a calcium (II) complex [CaI(BDI)]2. With the presence of THF, the reduction of [CaI(BDI)]2 with K/KI could afford red-brown crystals. The single crystal X-ray analysis revealed a centrosymmetric dimer with terminal BDI ligands and side-on bridging N2 units. The N-N distance in complex (1.258(3) and 1.268(3) Å) is remarkably longer than that of dinitrogen triple-bond (1.098 Å) and comparable with N=N double bond character in N22-. The N22ˉ anion could also be protonated to diazene (N2H2) with the intramolecular deprotonation of THF under the heating condition.
N2 activation by boron
Dicoordinate borylene has a filled p orbital and an empty sp-hybridized orbital in appropriate symmetry that can interact with inert small molecules like dinitrogen. In 2018, Braunschweig et al. reported the nitrogen fixation and reduction by active borylene species. [(CAAC)BDurBr2] could smoothly undergo one-electron reduction with the limited amount of KC8 (1.5 equiv.) and afford a radical complex [(CAAC)BDurBr]·. The radical complex could be further reduced, forming the transient dicoordinate borylene species and thus had the ability to activate dinitrogen. The filled p orbital of borylene, which acted as a Lewis base, donated to the π* antibonding orbital of N2. The empty sp2 orbital, which acted as a Lewis acid, accepted the electrons from N2 through σ donation. Following the further reduction by KC8 and stabilization by another borylene molecule, the dipotassium complex {[(CAAC)DurB]2(μ2-N2K2)} was formed in crystalline solid. Exposure of the dipotassium complex with ambient air and distilled water leads to the formation of dinitrogen bis(borylene) compound {[(CAAC)DurB]2(μ2-N2)} and a paramagnetic diradical complex {[(CAAC)DurB]2(μ2 -N2H2)}. Further protonation and reduction of {[(CAAC)DurB]2(μ2 -N2H2)} could lead to the cleavage of central N-N bond, which could finally lead to the formation of ammonium chloride in one-pot reaction.
Repeating the same reaction but replacing Dur (2,3,5,6-tetramethyl-phenyl) group by a bulkier Tip (2,4,6-triisopropylphenyl) group resulted in a very different result: after the dinitrogen was coordinated by the first borylene molecule, the second coordination by another borylene molecule was considerably hindered by steric repulsion in the case of the bulkier 4-Tip. Instead, the reductive dimerization of transient borylene [(CAAC)BTip] could occur in the presence of extra KC8, affording the complex {[(CAAC)-TipB]2(μ2-N4K2)}, a product with catenation of two N2 molecules, forming a N4 chain. It should be mentioned that this kind of coupling reaction was never found in the transition-metal-mediated N2 activation processes.
For borylene molecules, two-electron-filled p orbital and vacant sp2 orbital provide two push–pull channels to activate dinitrogen. Similarly, for boron radicals, one-electron-filled p orbital and vacant sp2 orbital provide two channels to activate N2. In 2022, Mézailles et al. reported the N2 activation by in situ generated boron-centered radicals. Though key intermediate which activated N2 is unclear, DFT calculation suggested that the coordination of N2 occurs prior to the second chloride elimination. Following the further reduction and coordination of boron, N2 was finally reduced to its lowest oxidation state and a mixture of two borylamine compounds, N(BCy2)3 and NH(BCy2)2, were generated.
N2 activation by carbon
Carbene species have also been considered a good choice to activate N2. The decomposition of diazoalkanes with the release of N2 is one of the most widely used strategies to produce carbenes. Its reverse reaction could be considered as the activation of N2 with carbenes. For example, in 1992, Dailey et al. reported that the photolysis of 3-bromo-3-(trifluoromethyl)diazirines in an argon matrix could afford bromo(trifluoromethyl)carbene. Bromo(trifluoromethyl)carbene could rebound N2 photochemically in matrix to form the corresponding diazo compound.
References
Chemical reactions | Main-group element-mediated activation of dinitrogen | [
"Chemistry"
] | 1,398 | [
"nan"
] |
72,431,089 | https://en.wikipedia.org/wiki/Eugenia%20O%27Reilly-Regueiro | Eugenia O'Reilly-Regueiro is a Mexican mathematician specializing in algebraic combinatorics and particular in the symmetries of combinatorial designs, circulant graphs, and abstract polytopes. She is a researcher in the Institute of Mathematics of the National Autonomous University of Mexico (UNAM).
Education and career
O'Reilly-Regueiro is originally from Mexico City. She was a mathematics student at UNAM, graduating in 1995. For the next two years she continued to work at UNAM as an assistant in the mathematics department of the Faculty of Chemistry, while studying harpsichord at UNAM's , working there with musician Luisa Durón.
Next, with a scholarship from the UNAM Dirección General de Asuntos del Personal Académico (DGAPA), she traveled to England for graduate study at Imperial College London, at that time part of the University of London system. She completed her PhD in 2003. Her dissertation, Flag-Transitive Symmetric Designs, was supervised by Martin Liebeck.
On completing her doctorate, she returned to UNAM as a researcher for the Institute of Mathematics.
Recognition
O'Reilly-Regueiro was elected to the Mexican Academy of Sciences in 2022.
References
External links
Home page
Year of birth missing (living people)
Living people
Mexican mathematicians
Mexican women mathematicians
Combinatorialists
Members of the Mexican Academy of Sciences | Eugenia O'Reilly-Regueiro | [
"Mathematics"
] | 282 | [
"Combinatorialists",
"Combinatorics"
] |
72,431,255 | https://en.wikipedia.org/wiki/Ken%20A.%20Paller | Ken A. Paller is an American neuroscientist who is a professor of psychology at Northwestern University in Evanston, Illinois, USA. He holds the James Padilla Chair in Arts & Sciences and serves as Director of the Cognitive Neuroscience Program in the Weinberg College of Arts & Sciences at Northwestern. He directs the Training Program in the Neuroscience of Human Cognition at Northwestern, with support from the National Institute of Neurological Disorders and Stroke. His work in cognitive neuroscience focuses on human memory, consciousness, sleep, dreaming, and related topics.
Paller has published over 300 scientific articles, reviews, and book chapters. His research has been funded by the National Science Foundation, the National Institutes of Health. the Mind Science Foundation, the Mind and Life Institute, the McKnight Foundation and the Alzheimer's Association, among others. Paller served as Editor for the Memory Section of the journal Neuropsychologia from 2008 to 2016, and remains on the Editorial Advisory Board. From 2011 to 2015 he served on the Annual Meeting Program Committee for the Cognitive Neuroscience Society, chairing the committee for 2014 and 2015. He is a Fellow of the Association for Psychological Science and a Fellow of the Mind and Life Institute.
Research
Paller's early research focused on aspects of human memory, including encoding and retrieval. He studied patients with memory disorders and healthy individuals using behavioral, electrophysiological, and neuroimaging methods. His early work documented neural signals at initial memory formation that predicted whether or not information would be remembered later. In a paper with Marta Kutas and Andrew R. Mayes in 1987, he introduced the term Dm to refer to the electrophysiological differences produced as a function of later memory performance. With Brian Gonsalves and other colleagues, he studied neural events that led to false memories. With Joel Voss, he also used electrophysiological methods to document differences in brain responses between conscious and unconscious memory phenomena. Whereas memory phenomena are typically assessed in recall and recognition tests (declarative memory tests), Voss and Paller found different results when unconscious memory was assessed, as in conceptual priming and implicit memory tests.
Paller's later research concerned the idea that learning is not a function only of the initial acquisition of knowledge, but that there are additional processing steps (known as consolidation) and that some of the work of consolidation takes place in the brain during sleep. Work in his laboratory was prominent in showing how subtle auditory stimulation during sleep could shape memory storage.
These studies used a method that came to be known as Targeted Memory Reactivation (TMR). Studies with TMR showed that many types of learning are improved when pre-sleep learning is followed by memory reactivation during sleep.
Paller's lab group also contributed to adapting the TMR method to produce lucid-dreaming experiences. In the study of these unusual experiences, when people realize they are dreaming in the midst of a dream, real-time two-way communication between dreamer and experimenter was demonstrated. In this way, the study of dreams can now include data on people's experiences during a dream along with associated neural activity, instead of relying exclusively on people's reports after they wake up to find out about their dreams.
Selected papers
References
Northwestern University faculty
Memory researchers
Sleep researchers
University of California, Los Angeles alumni
University of California, San Diego alumni
Living people
Year of birth missing (living people)
21st-century American psychologists
20th-century American psychologists | Ken A. Paller | [
"Biology"
] | 704 | [
"Sleep researchers",
"Behavior",
"Sleep"
] |
72,433,407 | https://en.wikipedia.org/wiki/Pleurotus%20albidus | Pleurotus albidus is a species of edible fungus in the family Pleurotaceae. Found in Caribbean, Central America and South America, it was described as new to science by Miles Joseph Berkeley, and given its current name by David Norman Pegler in 1983. It grows on trees such as Salix humboldtiana, other willows, Populus and Araucaria angustifolia, and can be cultivated by humans. Phylogenetic research has shown that while it belongs to P. ostreatus clade, it forms its own intersterility group.
See also
List of Pleurotus species
References
External links
Fungi described in 1983
Fungi of South America
Pleurotaceae
Fungus species | Pleurotus albidus | [
"Biology"
] | 141 | [
"Fungi",
"Fungus species"
] |
72,436,244 | https://en.wikipedia.org/wiki/Motus%20%28wildlife%20tracking%20network%29 | Motus (Latin for movement) is a network of radio receivers for tracking signals from transmitters attached to wild animals. Motus uses radio telemetry for real-time tracking. It was launched by Birds Canada in 2014 in the US and Canada.
, more than 1,500 receiver stations had been installed in 34 countries. Most receivers are concentrated in the United States and Canada, where the network began. The network has spread rapidly because it provides important key data useful to researchers and conservationists, both nationally and internationally.
The Motus transmitter's great advantage is its small size and weight. Transmitters weigh , and can therefore be attached to all animals, even insects such as a bee or butterfly.
Once a researcher or organization receives state and federal permits, they only need to acquire the appropriate transmitters and attach them to their study objects. Current transmitters' range (depending on size) is up to 12 miles (20 kilometers).
The long-used geolocators and GPS loggers are light and small but only store the desired data; they cannot wirelessly transmit the data. This means that researchers must recapture the transmitter-equipped animal to read the stored information, which can take a long time, and many times is unsuccessful.
The transmitter is attached in a suitable way, depending on the animal to be tracked, either with a thread or an adhesive. After a certain time the glue and thread dissolve and the transmitter falls off, in the meantime having transmitted all the data to the receivers it passed.
References
External links
Schematic view of the Motus system.
Picture of a swallow fitted with a motus transmitter.
Radio technology
Zoology
Animal migration
Geopositioning | Motus (wildlife tracking network) | [
"Technology",
"Engineering",
"Biology"
] | 336 | [
"Information and communications technology",
"Telecommunications engineering",
"Wireless locating",
"Radio technology",
"Wildlife conservation",
"Zoology",
"Biodiversity"
] |
72,436,518 | https://en.wikipedia.org/wiki/Quiet%20and%20loud%20aliens | The concept of quiet and loud aliens is used in the modelling of hypotheses for the prevalence of extraterrestrial intelligence, particularly in the context of the Fermi Paradox. Hypothetical "loud" aliens expand their sphere of influence rapidly in a highly detectable way; hypothetical "quiet" aliens are hard or impossible to detect. A special type of loud alien civilizations are "grabby aliens" who also inhibit the development of other technological civilizations in their sphere of influence.
See also
Anthropic principle
Dark forest hypothesis
Search for extraterrestrial intelligence
References
Astrobiology
Fermi paradox
Search for extraterrestrial intelligence | Quiet and loud aliens | [
"Astronomy",
"Biology"
] | 127 | [
"Astronomical hypotheses",
"Origin of life",
"Astrobiology stubs",
"Hypothetical life forms",
"Extraterrestrial life",
"Speculative evolution",
"Astronomy stubs",
"Astrobiology",
"Astronomical controversies",
"Fermi paradox",
"Biological hypotheses",
"Astronomical sub-disciplines"
] |
72,437,282 | https://en.wikipedia.org/wiki/Yield%20%28hydrology%29 | The term yield is used to describe the volume of water escaping from a spring over a certain period of time, the discharge quantity of which is measured in [l/s]. Measurement methods include volume–filling-time measurement and water level measurement.
The discharge of a spring can fluctuate to a greater or lesser extent depending on precipitation and evaporation. Karst springs show particularly large time-dependent differences in the discharge.
References
Bibliography
Murawski, Hans and Wilhelm Meyer (2010). Geologisches Wörterbuch. 12th edn. Heidelberg: Spectrum.
Limnology
Hydrogeology | Yield (hydrology) | [
"Environmental_science"
] | 123 | [
"Hydrology",
"Hydrology stubs",
"Hydrogeology"
] |
72,437,776 | https://en.wikipedia.org/wiki/2-Methoxyethoxymethyl%20chloride | 2-Methoxyethoxymethyl chloride is an organic compound with formula . A colorless liquid, it is classified as a chloroalkyl ether. It is used as an alkylating agent. In organic synthesis, it is used for introducing the methoxyethoxy ether (MEM) protecting group. MEM protecting groups are generally preferred to methoxymethyl (MOM) protecting groups, both in terms of formation and removal.
Typically, the alcohol to be protected is deprotonated with a non-nucleophilic base such as N,N-diisopropylethylamine (DIPEA, Hunig's base) in dichloromethane followed by addition of 2-methoxyethoxymethyl chloride.
The MEM protecting group can be cleaved (deprotection) with a range of Lewis and Bronsted acids.
Safety
The closely related chloromethyl methyl ether is a known human carcinogen.
References
Reagents for organic chemistry
Alkylating agents
Protecting groups
Organochlorides
Ethers
IARC Group 1 carcinogens | 2-Methoxyethoxymethyl chloride | [
"Chemistry"
] | 238 | [
"Protecting groups",
"Alkylating agents",
"Functional groups",
"Reagents for organic chemistry"
] |
72,437,868 | https://en.wikipedia.org/wiki/RS%20Sagittarii | RS Sagittarii is an eclipsing binary star system in the southern constellation of Sagittarius, abbreviated RS Sgr. It is a double-lined spectroscopic binary with an orbital period of 2.416 days, indicating that the components are too close to each other to be individually resolved. The system has a combined apparent visual magnitude of 6.01, which is bright enough to be faintly visible to the naked eye. During the primary eclipse the brightness drops to magnitude 6.97, while the secondary eclipse is of magnitude 6.28. The distance to this system is approximately 1,420 light years based on parallax measurements.
The variability of this system was initially suspected by B. A. Gould in 1879, then confirmed by A. W. Roberts in 1895. Roberts determined this to be an Algol-type variable with a period of 2.416 days. In his 1915 study of eclipsing binaries, H. Shapley listed a low orbital eccentricity of 0.091 for this binary system. He considered both eclipses to be partial, but only after correcting for limb darkening. R. S. Dugan and F. W. Wright in 1939 discovered evidence that suggested the period is varying.
R. L. Baglow in 1948 found an essentially circular orbit with a primary component of spectral class B5. By 1986, O. E. Ferrer and J. Sahade were able to extract spectral information about the secondary component, finding the system consists of ordinary main sequence stars of classes B5V and A2V. Hydrogen alpha emission lines suggested that the stars are interacting. The system appears to be semidetached, and may have already undergone a mass exchange phase.
The primary component of the system is the more massive of the pair, having 7.18 times the mass of the Sun compared to 2.41 times the Sun's mass for the secondary member. The primary is the larger star, with 5.11 times the Sun's radius while the secondary has 2.41 solar radii. The pair are separated by about 16 times the radius of the Sun. The primary is radiating 1,350 times the Sun's luminosity from its photosphere at an effective temperature of 15,480 K. The cooler secondary is 8,760 K and radiates 89.1 times the luminosity of the Sun.
RS Sgr shares a common proper motion with the 9th-magnitude stars TYC-7400-1102-1 and HD 167669, and they would form a quadruple system. Any orbits would take hundreds of thousands of years. TYC-7400-1102-1 is an A1 main-sequence star with a mass around twice that of the Sun, while HD 167669 is a slightly brighter B9 main sequence star with a mass about three times the Sun's. HD 167669 itself has a close optical companion, but it appears to be much more distant. Together with RS Sgr, these stars have the Washington Double Star Catalog designation WDS J18176-3406.
References
B-type main-sequence stars
A-type main-sequence stars
Algol variables
Sagittarius (constellation)
6833
Durchmusterung objects
167647
89637
Sagittarii, RS | RS Sagittarii | [
"Astronomy"
] | 683 | [
"Sagittarius (constellation)",
"Constellations"
] |
72,439,008 | https://en.wikipedia.org/wiki/Membrane-mediated%20anesthesia | Membrane-mediated anesthesia or anaesthesia (UK) is a mechanism of action that involves an anesthetic agent exerting its pharmaceutical effects primarily through interaction with the lipid bilayer membrane.
The relationship between volatile (inhalable) general anesthetics and the cellular lipid membrane has been well established since around 1900, based on the Meyer-Overton Correlation. Since 1900 there have been extensive research efforts to characterize these membrane-mediated effects of anesthesia, leading to many theories but few answers. During the 1980s the focus of anesthetic research shifted from membrane lipids to membrane proteins, where it currently remains. Accordingly, the specific membrane-mediated anesthetic effects remain mostly undiscovered.
Recent research has demonstrated promising mechanisms of membrane-mediated anesthetic action for both general and Local anesthetics. These studies suggest that the anesthetic binding site in the membrane is within ordered lipids. This binding disrupts the function of the ordered lipids, forming lipid rafts that dislodge a membrane-bound phospholipase involved in a metabolic pathway that actives anesthetic-sensitive potassium channels. Other recent studies show similar lipid-raft-specific anesthetic effects on sodium channels.
See Theories of general anaesthetic action for a broader discussion of purely theoretical mechanisms.
The Meyer-Overton Correlation for Anesthetics
At the turn of the twentieth century, one of the most important anesthetic-based theories began to take shape. At the time, the research of both German pharmacologist Hans Horst Meyer (1899) and British-Swedish physiologist Charles Ernest Overton (1901) reached the same conclusion about general anesthetics and lipids:
There is a direct correlation between anesthetic agents and lipid solubility. The more lipophillic the anesthetic agent is, the more potent the anesthetic agent is.
This principle became known as the Meyer-Overton Correlation. It originally compared the anesthetic partition coefficient in olive oil (X-axis) to the effective dose that induced anesthesia in 50% (i.e., EC50) of the tadpole research subjects (Y-axis). Modern renditions of the Meyer-Overton plot usually compare olive oil partition coefficient of the Inhalational or Intravenous drug (X-axis) to the minimum alveolar concentration (MAC) or the effective dose 50 (i.e., ED50) of the anesthetic agent (Y-axis).
Despite more than 175 years of anesthetic use and research, the exact connection between phospholipids, the bilayer membrane, and general anesthetic agents remains mostly unknown. Accordingly, the means of membrane-mediated anesthesia remain mostly theoretical.
The Lateral Pressure Profile Theory
The Lateral Pressure Profile theory suggests that anesthetic agents partition into the lipid bilayer, increasing the horizontal (lateral) pressure on proteins imbedded in the membrane. The added pressure causes a conformational change in protein structure, forcing the neuronal channel into an open or closed state (e.g., hyperpolarization) that generates the Inhibitory state of general anesthesia in the central nervous system (CNS).
This is the first hypothesis to explain the correlations of anesthetic potency with lipid bilayer structural characteristics, describing both mechanistic and thermodynamic rationale for the effects of general anesthesia.
General anesthetics
Inhaled anesthetics partition into the membrane and disrupt the function of ordered lipids. Membranes, like proteins, are composed of ordered and disordered regions. The ordered region of the membrane contains a palmitate binding site that drives the association of palmitoylated proteins to clusters of GM1 lipids (sometimes referred to as lipid rafts). Palmitate's binding to lipid rafts regulates the affinity of most proteins to lipid rafts.
Inhaled anesthetics partition into the lipid membrane and disrupt the binding of palmitate to GM1 lipids (see figure). The anesthetic binds to a specific palmitate site nonspecifically. The clusters of GM1 lipids persist, but they lose their ability to bind palmitoylated proteins.
PLD2
Phospholipase D2 (PLD2) is a palmitoylated protein that is activated by substrate presentation. Anesthetics cause PLD2 to move from GM1 lipids, where it lacks access to its substrate, to a PIP2 domain which has abundant PLD2 substrate. Animals with genetically depleted PLD2 were significantly resistant to anesthetics. The anesthetics xenon, chloroform, isofluorane, and propofol all activate PLD in cultured cells.
TREK-1
Twik-related potassium channel (TREK-1) is localized to ordered lipids through its interaction with PLD2. Displacement of the complex from GM1 lipids causes the complex to move to clusters. The product of PLD2, phosphatidic acid (PA) directly activates TREK-1. The anesthetic sensitivity of TREK-1 was shown to be through PLD2, and the sensitivity could be transferred to TRAAK, an otherwise anesthetic insensitive channel.
GABAAR
The membrane mediated mechanism is still being investigated. Nonetheless, the GABAAR gamma subunit is palmitoylated and the alpha subunit binds to PIP2. When the agonist GABA binds to GABAAR it causes a translocation to thin lipids near PIP2. Anesthetic disruption of Palmitate mediated localization should therefore cause the channel to move the same as an agonist, but this has not yet been confirmed.
Endocytosis
Endocytosis helps regulate the time an ion channel spends on the surface of the membrane. GM1 lipids are the site of endocytosis. The anesthetics hydroxychloroquine, tetracaine, and lidocaine blocked entry of palmitoylated protein into the endocytic pathway. By blocking access to GM1 lipids, anesthetics block access to endocytosis through a membrane-mediated mechanism.
Local anesthetics
Local anesthetics disrupt ordered lipid domains and this can cause PLD2 to leave a lipid raft. They also disrupt protein interactions with PIP2.
History
More than 100 years ago, a unifying theory of anesthesia was proposed based on the oil partition coefficient. In the 70s this concept was extended to the disruption of lipid partitioning. Partitioning itself is an integral part of forming the ordered domains in the membrane, and the proposed mechanism is very close to the current thinking, but the partitioning itself is not the target of the anesthetics. At clinical concentration, the anesthetics do not inhibit lipid partitioning. Rather they inhibit the order within the partition and/or compete for the palmitate binding site. Nonetheless, several of the early conceptual ideas about how disruption of lipid partitioning could affect an ion channel have merit.
References
Anesthesia
Biological matter
Drugs
Drugs with unknown mechanisms of action
GABAA receptor positive allosteric modulators
General anesthetics
History of anesthesia
Local anesthetics
Membrane biology
NMDA receptor antagonists | Membrane-mediated anesthesia | [
"Chemistry"
] | 1,528 | [
"Pharmacology",
"Products of chemical industry",
"Membrane biology",
"Molecular biology",
"Chemicals in medicine",
"Drugs"
] |
72,440,211 | https://en.wikipedia.org/wiki/Erik%20Ernst | Erik Ernst is a prominent computer scientist and an associate professor at the University of Aarhus in Denmark. In 2010, he won the Dahl-Nygaard Prize.
External links
References
Danish computer scientists
Living people
Dahl–Nygaard Prize
Academic staff of Aarhus University
Year of birth missing (living people) | Erik Ernst | [
"Technology"
] | 59 | [
"Computing stubs",
"Computer specialist stubs"
] |
72,440,309 | https://en.wikipedia.org/wiki/Littrow%20expansion | Littrow expansion and its counterpart Littrow compression are optical effects associated with slitless imaging spectrographs. These effects are named after Austrian physicist Otto von Littrow.
In a slitless imaging spectrograph, light is focused with a conventional optical system, which includes a transmission or reflection grating as in a conventional spectrograph. This disperses the light, according to wavelength, in one direction; but no slit is interposed into the beam. For pointlike objects (such as distant stars) this results in a spectrum on the focal plane of the instrument for each imaged object. For distributed objects with emission-line spectra (such as the Sun in extreme ultraviolet), it results in an image of the object at each wavelength of interest, overlapping on the focal plane, as in a spectroheliograph.
Description
The Littrow expansion/compression effect is an anamorphic distortion of single-wavelength image on the focal plane of the instrument, due to a geometric effect surrounding reflection or transmission at the grating. In particular, the angle of incidence and reflection from a flat mirror, measured from the direction normal to the mirror, have the relation
which implies
so that an image encoded in the angle of collimated light is reversed but not distorted by the reflection.
In a spectrograph, the angle of reflection in the dispersed direction depends in a more complicated way on the angle of incidence:
where is an integer and represents spectral order, is the wavelength of interest, and is the line spacing of the grating. Because the sine function (and its inverse) are nonlinear, this in general means that
for most values of and , yielding anamorphic distortion of the spectral image at each wavelength. When the magnitude is larger, images are expanded in the spectral direction; when the magnitude is smaller, they are compressed.
For the special case where
the reflected ray exits the grating exactly back along the incident ray, and ; this is the Littrow configuration, and the specific angle for which this configuration holds is the Littrow angle. This configuration preserves the image aspect ratio in the reflected beam. All other incidence angles yield either Littrow expansion or Littrow compression of the collimated image.
References
Spectroscopy | Littrow expansion | [
"Physics",
"Chemistry"
] | 455 | [
"Instrumental analysis",
"Molecular physics",
"Spectroscopy",
"Spectrum (physical sciences)"
] |
72,440,978 | https://en.wikipedia.org/wiki/Curviacus | Curviacus is a genus of Ediacaran organism of uncertain lineage that displays a modular body plan consisting of crescent-shaped chambers. It contains a single species, Curviacus ediacaranus.
Etymology
The genus name Curviacus references the shape of the crescent chambers; coming from Latin curvus meaning curved and acus meaning needle.
Phylogeny
The phylogeny of this fossil is not yet known. Some scientists believe the genus to be a coralline algal or fungal stem group.
Occurrence
C. ediacaranus is from the late Ediacaran. The fossil C. ediacaranus has been found in the Shibantan Member of the Dengying Formation. The Shibantan Member is the bituminous limestone section of the formation. It is unusual for Ediacaran biota to be preserved in limestone. As such, C. ediacaranus is the only Palaeopascichnus fossil to be reported from carbonate rock rather than siliclastic rock. This special type of fossilization allows for 3-dimensional analysis.
Description
These fossils occur on bituminous limestone on the bedding surface. The fossilized specimen has calcispar walls with the inner chambers filled with micrite. The walls are raised because the calcispar does not erode as easily. C. ediacaranus is a slightly oblong macrofossil that ranges from 5–14 cm in length. It is characterized by its curved or crescent-shaped chambers that occur arranged in a series with the chambers sharing walls. All of the chambers are convex in the same direction. Each chamber is narrow ranging ~1-3mm in width. Chamber length can be consistent or inconsistent. Inconsistencies can give a false impression of branching. Additionally, the walls of the chambers sometimes converge laterally.
References
Ediacaran life
Incertae sedis | Curviacus | [
"Biology"
] | 386 | [
"Incertae sedis",
"Taxonomy (biology)"
] |
72,441,060 | https://en.wikipedia.org/wiki/Jacobi%20bound%20problem | The Jacobi bound problem concerns the veracity of Jacobi's inequality which is an inequality on the absolute dimension of a differential algebraic variety in terms of its defining equations.
This is one of Kolchin's Problems.
The inequality is the differential algebraic analog of Bézout's theorem in affine space.
Although first formulated by Jacobi, In 1936 Joseph Ritt recognized the problem as non-rigorous in that Jacobi didn't even have a rigorous notion of absolute dimension (Jacobi and Ritt used the term "order" - which Ritt first gave a rigorous definition for using the notion of transcendence degree).
Intuitively, the absolute dimension is the number of constants of integration required to specify a solution of a system of ordinary differential equations.
A mathematical proof of the inequality has been open since 1936.
Statement
Let be a differential field of characteristic zero and consider a differential algebraic variety determined by the vanishing of differential polynomials .
If is an irreducible component of of finite absolute dimension then
In the above display is the *jacobi number*.
It is defined to be
.
References
Unsolved problems in mathematics
Differential algebra | Jacobi bound problem | [
"Mathematics"
] | 235 | [
"Differential algebra",
"Fields of abstract algebra",
"Unsolved problems in mathematics",
"Mathematical problems"
] |
72,442,034 | https://en.wikipedia.org/wiki/NGC%205502 | NGC 5502 (also known as NGC 5503) is a spiral galaxy in the constellation of Ursa Major, registered in New General Catalogue (NGC).
Observation history
NGC 5502 was discovered by Edward Swift (father) on 9 May 1885 and later double listed by Lewis Swift (son) two days later on 11 May 1885 as NGC 5503. They gave descriptions "between two stars, one a wide double" and "forms with two stars a right triangle" respectively. In the New General Catalogue, John Louis Emil Dreyer described the galaxy as "most extremely faint, very small, round, very difficult, 2 stars near". The apparent difference in positions (2 arcmin) could have caused the confusions between NGC 5502 and NGC 5503.
Notes
References
Galaxies discovered in 1885
5502
Astronomical objects discovered in 1885
Spiral galaxies
NGC 5502 | NGC 5502 | [
"Astronomy"
] | 174 | [
"Ursa Major",
"Constellations"
] |
72,442,626 | https://en.wikipedia.org/wiki/Iron%20superoxide%20dismutase | Iron superoxide dismutase (FeSOD) is a metalloenzyme that belongs to the superoxide dismutases family of enzymes. Like other superoxide dismutases, it catalyses the dismutation of superoxides into diatomic oxygen and hydrogen peroxide. Found primarily in prokaryotes such as Escherichia coli and present in all strict anaerobes, examples of FeSOD have also been isolated from eukaryotes, such as Vigna unguiculata.
Found within the cytosol, mitochondria, and chloroplasts, FeSOD's ability to disproportionate superoxides provides cells with protection against oxidative stress and other processes that produce superoxides such as photosynthesis. It is important for organisms to disproportionate superoxides, as superoxides themselves are not particularly harmful but have the potential to turn into a hydroxyl radical, which is unable to be eliminated in an enzymatic reaction.
History
FeSOD was first isolated from E. coli by Yost et al. in 1973 and was the third discovery in the family of bacterial superoxide dismutases, with copper-zinc superoxide dismutase being discovered in 1969 and FeSOD's structural equivalent, manganese superoxide dismutase (MnSOD), being discovered in 1970. The fourth, nickel superoxide dismutase, was first isolated in 1996.
Along with being one of the oldest enzymes known, FeSOD is the oldest known superoxide dismutase due to the high bioavailability of iron during the Archean eon. FeSOD first appeared in photoferrotrophic bacteria, then later in cyanobacteria as the Great Oxidation Event locked up much of the free iron in iron oxides and increased the need for cyanobacteria to have reactive oxygen species defences.
Structure
FeSOD is a structural homolog of MnSOD, although there are minor differences in eukaryotic FeSOD, such as a loop connecting the β1 and β2 strands within the enzyme. FeSOD can also exist in homodimeric or homotetrameric forms, depending on the organism.
Mechanism
Like its structural homolog MnSOD, FeSOD disproportionates superoxide via the transport of a single electron by the Fe2+/Fe3+ redox couple. There are two separate reactions by which FeSOD can process superoxide:
Fe3+-SOD + → Fe2+-SOD + O2
Fe2+-SOD + + 2H+ →Fe3+-SOD + H2O2
In order for the superoxide to be disproportionated, however, it must first be protonated. The delivery of the proton is believed to be an H2O ligand, the transport of which is mediated by a local glutamine from ambient water within the cell.
References
Metalloproteins
Iron enzymes | Iron superoxide dismutase | [
"Chemistry"
] | 639 | [
"Metalloproteins",
"Bioinorganic chemistry"
] |
72,443,416 | https://en.wikipedia.org/wiki/Orka-class%20submarine | The Orka-class submarine is a future submarine class currently planned for the Royal Netherlands Navy. The submarines will replace the aging .
History
Plans were announced by Dutch Minister of Defence, Jeanine Hennis-Plasschaert, in November 2014 to replace the s with four new submarines in 2025. By 2017, there was still no political agreement on the quantity or type of new submarines to be ordered; nor the tasks they were expected to perform. However, it seems certain that they will be replaced, since the alleged Russian threat was regarded as an incentive to invest in a new class. The Minister of Defence, however, delayed the replacement by two years, until 2027. Roughly, there are two groups in the Dutch parliament – one in favor of replacing the Walrus class by an equally capable class of large, expeditionary, diesel-electric submarine, and the other in favor of choosing a cheaper solution of smaller diesel-electrics, similar to Swedish and German submarines. It is unknown where the new boats will be built; since the Dutch RDM shipyard (the only Dutch yard capable of building submarines) is no longer in operation. The Defensienota (Defense policy for the coming years) of March 2018 revealed that the Dutch government is still planning to replace the Walrus-class submarines, with an allocated budget of more than 2.5 billion euros for the new submarines. Additional information on how to proceed with the replacement was expected at the end of 2018, when the Dutch Minister of Defence, Ank Bijleveld, was to send a so-called B-letter to the Dutch parliament. Minister Bijleveld also underlined in an interview that the new submarines should have the same niche capabilities as the current Walrus-class submarines: the ability to operate and gather intelligence in both shallow water close to the coast and in deep water in the ocean. In mid-2021 it was indicated that the revised plan was to take a decision on the replacement type in 2022 and to have the first vessel in service by 2028, with the first two boats to be in service by 2031. However, by October 2021 it was reported that this timeline was no longer feasible. Instead, the Dutch Ministry of Defence signalled that the envisaged dates would have to be "substantially adjusted", likely impacting the originally proposed in-service dates for the first submarines. In April 2022 it was announced that the revised schedule for construction of the new replacement boats would likely see the first two vessels entering service in the 2034 to 2037 timeframe.
On 16 November 2022 the next phase in the program was started when DMO delivered the request for quotation (RfQ) to the three remaining yards. It is expected that the proposals will come in during the summer of 2023 with a final decision being made by the navy in late 2023 or early 2024.
Contenders
The Ministry of Defence has shortlisted three bidders:
Damen Group and Saab Group announced that they have partnered from 2015 to jointly develop, offer and build next-generation submarines that are able to replace the current Walrus-class submarines. It was announced on 1 June 2018 that their design will be derived from the A26 submarine. The proposed submarine is around long with a beam of . Furthermore, the displacement will be around , with a complement of 34 to 42 people. The boat's armament includes six torpedo tubes and one multi-mission lock which can be used to deploy special forces. On 28 July 2023 they submitted a submarine design for the Walrus class replacement program that is called C718. The offer includes knowledge transfer so that the Royal Netherlands Navy can perform maintenance and upgrade the submarines during their lifespan by themselves.
Naval Group announced that it is offering its newest submarine class, the Barracuda class, as replacement for the Walrus class. A version of the "Shortfin" diesel-electric variant Barracuda class was offered, rather than the nuclear variant used by the French Navy.
ThyssenKrupp Marine Systems is (as of December 2019) planning to offer a Type 212CD submarine.
Spain's Navantia's S-80 was not accepted as a contender following the B-letter in 2019. In 2022 the Spanish Ministry of Defence sent a letter to the Dutch DMO for Navantia to be allowed to put in an offer following a RfQ sent to the remaining contenders, in which some of the requirements have changed. It is rumoured that the request was denied by DMO.
Winning bid
On 15 March 2024 State Secretary for Defence Christophe van der Maat officially announced that Naval Group has been selected as the winning bid. Prior to this announcement, the winner was already leaked to several media outlets, which caused political backlash for choosing a foreign yard over a Dutch one. In April 2024, it was announced which ten Dutch companies and two knowledge institutions will be involved in the construction of the Orka class submarines.
The names of the new submarines where also announced by van der Maat. The class will be known as the Orka class, with the subs named Orka (Orca), Zwaardvis (Swordfish), Barracuda (Barracuda) and Tijgerhaai (Tiger shark). The first two will be delivered within ten years after the contract has been signed.
Ships in class
See also
Royal Netherlands Navy Submarine Service
Future of the Royal Netherlands Navy
Attack-class submarine
Citations
Submarines of the Netherlands
Military acquisition
Military projects
Proposed ships of the Royal Netherlands Navy
Submarine classes | Orka-class submarine | [
"Engineering"
] | 1,124 | [
"Military projects"
] |
72,444,388 | https://en.wikipedia.org/wiki/Australian%20Frog%20Calls | Australian Frog Calls (also referred to as Songs of Disappearance: Australian Frog Calls) is an album of Australian frog calls, released on 2 December 2022 by the Bowerbird Collective and Australian Museum. It The album debuted at number 3 on the ARIA Charts.
Background
The album follows Australian Bird Calls, which was composed of endangered Australian bird calls and peaked at number 2 on the ARIA Charts in February 2022.
Production
Australian Frog Calls was a collaboration between the Bowerbird Collective, Australian Museum FrogID project, Listening Earth and Mervyn Street of Mangkaja Arts. The album was produced by Anthony Albrecht.
Description and impact
The album is a compilation of frog sounds from both biologist recordings and public submissions. Calls featured on the album date back to the 1970s from FrogID's database.
The project brings attention to FrogID Week, an annual event where the public are encouraged to download the free FrogID app and record the frogs they hear calling around them. The project also highlights that one in six Australian native frog species are currently threatened, with four already extinct. In addition to raising awareness, proceeds from the album are donated to the Australian Museum's national FrogID project. FrogID project coordinator Nadiah Roslan said "Frogs are amongst the most threatened groups of animals on the planet and declining more rapidly than any other animal group... This decline is concerning because we need frogs to be around—they play such an important role in healthy ecosystems and this role can't be filled by any other animal group."
Release and reception
The album was released on 2 December 2022.
It debuted at number 3 on the ARIA Charts, and was nominated for ARIA Award for Best World Music Album at the 2023 ARIA Music Awards.
Reception
A staff writer at The Music posted a review consisting entirely of frog noises.
The album debuted at number 3 on the ARIA charts behind Paul Kelly's Christmas Train and Taylor Swift's Midnights.
Track listing
Charts
References
External links
Official website
2022 albums
Animal sounds | Australian Frog Calls | [
"Biology"
] | 406 | [
"Ethology",
"Behavior",
"Animal sounds"
] |
72,444,526 | https://en.wikipedia.org/wiki/Songs%20of%20Disappearance | Songs of Disappearance is a series of albums by Bowerbird Collective.
Discography
Awards and nominations
ARIA Music Awards
The ARIA Music Awards is an annual award ceremony event celebrating the Australian music industry.
!
|-
| 2023
| Australian Frog Calls
| Best World Music Album
|
|
|-
References
Animal sounds
2020s compilation albums | Songs of Disappearance | [
"Biology"
] | 66 | [
"Ethology",
"Behavior",
"Animal sounds"
] |
76,854,532 | https://en.wikipedia.org/wiki/Space%20animal%20hypothesis | The space animal hypothesis proposes that reports of flying saucers or UFOs might be caused not by technological alien spacecraft or mass hysteria, but rather by animal lifeforms ("space critters") that are indigenous to Earth's atmosphere or interplanetary space.
Proponents
Multiple authors independently suggested the space animal hypothesis. In 1923, paranormal author Charles Fort had mused "It seems no more incredible that up in the seemingly unoccupied sky there should be hosts of living things than that the seeming blank of the ocean should swarm with life".
During the 1947 flying disc craze, a fan of Fort's writings named John Philip Bessor became the first modern proponent of the hypothesis when he authored a letter to the Air Force suggesting that discs might be "animals bearing very little likeness to human beings". In 1949, he wrote to the Saturday Evening Post to suggest that the discs might be "more like octopuses, in mentality, than humans". In 1957, a saucer group's newsletter credited Bessor with the "space animal" idea, and in 1978 he was called the "grand-daddy" of the "space critter" hypothesis.
In 1948, the Saturday Evening Post quoted Luis Walter Alvarez's opinion that the "gizmos" appeared to be "alive".
In April 1949, the Air Force's Project Sign released an essay which considered the hypothesis, writing "the possible existence of some sort of strange extraterrestrial animals has been remotely considered, as many of the objects described acted more like animals than anything else".
In January 1951, Fate magazine published the opinion of David W. Chase who argued that the "saucers are the beings themselves". In 1952, papers speculated that flying saucers were "not carriers for the inhabitants of other planets" but rather that flying saucers "are the living creatures from another planet". In 1953, Walter Karig speculated in American Weekly that the objects behaved more like "puppies" than spaceships. That year, Desmond Leslie's book Flying Saucers Have Landed speculated that a UFO reported over Oloron and Gaillac France might been a "huge living thing". In 1954, French engineer Rene Fouere published his theory that the "disc-beings" were able to live in space. In October 1954, Alfred Loedding was publicly quoted on his suspicion that the disks "may be a kind of space animal".
By 1955, original saucer witness Kenneth Arnold began to promote the theory, suggesting that the UFOs are "sort of like sky jellyfish." Arnold added: "My theory might sound funny, but just remember that there are a lot of things in nature that we don’t know yet." In 1962, he argued "the so-called unidentified flying objects that have been seen in our atmosphere are not spaceships from another planet at all, but are groups and masses of living organisms that are as much a part of our atmosphere and space as the life we find in the oceans."
In 1955, Austrian occultist Zoe Wassilko-Serecki argued that the saucers were ionospheric animals. Her writings, in turn, influenced Ivan T. Sanderson who became the "most eminent advocate" of the space animal idea. In 1967, Sanderson authored a book on the topic: Uninvited Visitors: A Biologist Looks at UFOs.
Trevor James Constable similarly argued that UFOs were in fact amoeba-like animals inhabiting the sky. According to Constable, the creatures could be the size of a coin or as large as half-a-mile across. Constable authored They Live in the Sky! (1958) and other books about his theory. In later decades, Constable invoked these beings to explain supposed cattle mutilations.
Space animals in fiction
Arthur Conan Doyle's 1913 short story "The Horror of the Heights" featured an aviator breaking an altitude record who discovered an "air jungle" full of translucent animals resembling jellyfish and snakes. In September 1936, Ramond Z. Gallum's short story "A Beast of the Void" envisioned creatures capable of interstellar travel. Star Trek explored the concept of space animals in episodes like "The Immunity Syndrome" (1968) and "Galaxy's Child" (1991). The Purrgil space whales in the Star Wars franchise are said to have inspired Hyperspace travel.
Jordan Peele's 2022 movie Nope featured a UFO that is revealed to be an animal. Peele and his team collaborated with marine biologists to design an undiscovered aerial predator with anatomical and locomotive elements inspired by jellyfish, octopus, and other marine lifeforms.
See also
1947 flying disc craze § contemporary interpretations
Bioship, a science fiction concept of living spaceships
Upper-atmospheric lightning
References
20th-century neologisms
Pseudoscience
Ufology | Space animal hypothesis | [
"Astronomy",
"Biology"
] | 994 | [
"Outer space",
"Hypothetical life forms",
"Extraterrestrial life",
"Space science",
"Astronomical controversies",
"Biological hypotheses"
] |
76,855,219 | https://en.wikipedia.org/wiki/IRAS%2005189-2524 | IRAS 05189-2524 is a galaxy merger located in the constellation Lepus. It is located 603 million light-years away from the Solar System and has an approximate diameter of 75,000 light-years.
A luminous galaxy
IRAS 05189-2524 is classified as an ultraluminous infrared galaxy (ULIRG), which is formed by two interacting gas-rich spiral galaxies that merged together. Signs left by merging process, included a single bright nucleus and an outer structure consisting one-sided extension of the inner arms, with its tidal tail formed by material ripped from the galaxies by gravitational forces.
IRAS 05189-2524 is one of the brightest local ULIRG in X-ray with a E = 2–10 keV continuum luminosity of ~1043 erg/s This tend to vary overtime in which the E = 0.5–2 keV was relatively constant during the 2001-2002 observation done by XMM Newton and Chandra. But in 2006 study done by Suzaku shows it was a factor of ~30 lower. The galaxy has a power output above 10 times that of our sun, emitting a tremendous amount of light at infrared wavelengths.
Moreover, IRAS 05189-2524 is classified an optical Seyfert 2 galaxy, presenting a hidden broadline region. A study noticed there is ~70% percent of the bolometric luminosity attributed to its active galactic nucleus, thus making it a quasar. It is represented by its dust enshrouded stage which is shed overtime by the nuclei. There is a sign of high-velocity large-scale outflows detached in neutral, ionized and molecular gas phrases.
An observation by XMM Newton and NuSTAR, shows evidence for a blueshifted Fe K absorption feature at E = 7.8 KeV which indicates there is an ultrafast outflow (UFO) with vout = 0.11 ± 0.01c. A relative disk reflection in the broadband X-ray spectrum, shows a highly asymmetric board Fe Kα emission line that extends down to 3 KeV with a Compton scattering component above 10 KeV.
Further studies shows there is a new, quasi-luminous hard X-ray and near-IR spectra in IRAS 05189-2524. The Seyfert nucleus is Compton-thin and the near-IR board lines are seen in transmission, similar to X-rays and the medium has an Aṿ/ɴH ratio that is lower than Galactic. Also, the increase in obscuration at latter approach shows less △Aṿ/△Nн compared to Galactic, thus supporting a correlation between the proximity to the center and properties of obscuring matter. Most of the observed polarization is due to dichroism given the fact, the measured AV is compatible with the broad component of Нα seen in transmission.
There are Na i D emission in the system traces dusty filaments on the near side of an extended active galactic nucleus in IRAS 05189-2524 which has projected velocities up to 2000 km/s. These filaments simultaneously obscure the stellar continuum, serving as complementary probe of the wind, in which they are the strongest in regions of low foreground obscuration.
References
2MASS objects
Lepus (constellation)
Luminous infrared galaxies
Seyfert galaxies
Galaxy mergers
017155
IRAS catalogue objects
017155 | IRAS 05189-2524 | [
"Astronomy"
] | 707 | [
"Lepus (constellation)",
"Constellations"
] |
76,855,460 | https://en.wikipedia.org/wiki/IC%204588 | IC 4588 is a type E elliptical galaxy located in the constellation Serpens. It is located 729 million light-years from the Solar System and has a dimension of 0.30 x 0.3 arcmin meaning its diameter is 64,000 light-years across. IC 4588 was discovered by Stephane Javelle on July 15, 1903.
In some galactic catalogues, NGC 6051 and IC 4588 have been listed as the same object. However, O'Sullivan and associates (2011) have them as separate entities, with NGC 6051 being the central dominant galaxy of a cluster.
Supernova
One supernova has been discovered in IC 4588 so far: SN 2023ifv.
SN 2023ifv
SN 2023ifv was discovered on May 13, 2023 by ATLAS (Asteroid Terrestrial-impact Last Alert System) which was developed by the University of Hawaii. It was reported by multiple astronomers from University of Hawaii, South African Astronomical Observatory, ESO, UAI Obstech, Oxford/QUB, Queen's University Belfast, Oxford and Harvard; via a cyan-ATLAS filter which was taken using ATLAS Haleakala telescope. The supernova reached a magnitude of 18.
On May 19, 2023, C. Fremling, D. Neill, and Y. Sharma on the behalf of the SDEM Team from Caltech and the Zwicky Transient Facility, confirmed SN 2023ifv to be a Type Ia supernova. The supernova probably resulted from the destruction of a white dwarf in a binary system.
References
Elliptical galaxies
Serpens
4588
6051
2MASS objects
SDSS objects
057025
057025
Astronomical objects discovered in 1903 | IC 4588 | [
"Astronomy"
] | 357 | [
"Constellations",
"Serpens"
] |
76,858,938 | https://en.wikipedia.org/wiki/Rat%20czar | A director of rodent mitigation, or a "rat czar", is a position appointed by local government. An employee with this title is given the sole task of decreasing the municipality's rat population. This person will coordinate with different agencies within the local government, private sector, and community organizations. This separates rats from a local government's pest control efforts, which is typically overseen by the Department of Public Works, inspection services, and the water and sewer commission. This is an effort to specifically target the vermin and centralize the issue.
History
On April 12, 2023, New York City appointed Kathleen Corradi to the position of rat czar to fight rats in New York City. The job posting reported the employee will "reduce the rat population, increase cleanliness, and prevent pestilence." Corradi previously worked in the city's education department. Under this new role, she was tasked with solely working on rat reduction to improve the health and quality of life for people living in New York City. She would be collaborating with different agencies to use their resources and target rats.
Along with creating the position of a rat czar, Mayor Eric Adams announced a $3.5 million investment to first target the rat population in Harlem. This investment would be spread over multiple agencies to test different reduction techniques, and would be overseen by Corradi.
Each state and city has their own way of handling pest control. However, once New York City made the move to publicize its hiring of a rat czar, other municipalities around the world took notice. After Boston was named one of the rattiest cities in the United States, local officials have brought forth plans for the city to create a rat czar position. London has also made efforts to create a rat czar position. Smaller towns like Somerville, Massachusetts have introduced the rat czar position. Cities like Chicago and Newark, New Jersey have their own Rodent Control Bureaus. Due to the widespread media coverage of the New York City rat czar position, the heads of these bureaus have been referred to by the same name.
In May 2024, Mayor Eric Adams announced the first ever "National Urban Rat Summit" that would bring in rodent mitigation experts and researches to gather and discuss the best ways to fight rats within cities. Officials from across the country congregated in September.
Responsibilities
Identification of areas of interest
In order to quell a rat population, the rat czar must identify where there are 'hot spots', or areas of interest to specifically target. The rat czar will tour areas and evaluate next steps. Community-member reports can also help identify potential rat nests. New York City announced its own 'Rat Pack' which locals could join by taking a New York Department of Health session and then join the rat czar on a 'rat walk' to identify areas in need.
Cleaning
After an area of interest has been identified, the rat czar and other employees will target the impact of the local rat population. This includes washing away rat droppings, picking up garbage that rats may eat, and trimming back shrubs and bushes so the rats have less areas to hide.
Prevention
Once the area has been wiped of a rat's presence, the rat czar and others will take preventative measures to ensure the area is no longer visited by rats. This includes sealing cracks in infrastructure, targeting rats burrows and nests, and trapping rats to rid them of the area.
Under the New York City rat czar, the Department of Sanitation enforced a new rule to target rat reduction. Residents, businesses, and building managers were instructed to put trash on the sidewalk no earlier than 6 p.m. All curbside trash bags were instructed to be rid of by 8 p.m.
Impact quantification
After all steps have been taken to ensure the rats have been cleared, the rat czar is in charge of tracking the community response. The rat czar will listen to community sighting reports and see if these actions have made an impact. This also means educating the public so the community knows how to handle and prevent rats.
Abatement
The rat czar is tasked with creating new ways for the rat population to be quelled. Colin Zeigler of Somerville has introduced dry ice, carbon dioxide poisoning, and SMART boxes that trap and electrocute rats.
References
Pest control
Politics of New York City | Rat czar | [
"Biology"
] | 891 | [
"Pests (organism)",
"Pest control"
] |
76,859,293 | https://en.wikipedia.org/wiki/Sodium%20chlorodifluoroacetate | Sodium chlorodifluoroacetate is the organofluorine compound with the formula . It is a salt formed by neutralization of chlorodifluoroacetic acid with sodium hydroxide. The compound, a white solid, is of interest as a source of difluorocarbene:
This reaction is conducted in a hot solution also containing the substrate. Diglyme is a typical solvent. The conversion of sodium chlorodifluoroacetate is proposed to start with decarboxylation, which generates the carbanion .
One set of applications is difluorocyclopropanation. Thermal decomposition of sodium chlorodifluoroacetate in the presence of triphenylphosphine and an aldehyde allows for a Wittig-like reactions In this case, is proposed as an intermediate.
References
Fluorides
Carbenes
Organic sodium salts | Sodium chlorodifluoroacetate | [
"Chemistry"
] | 191 | [
"Inorganic compounds",
"Salts",
"Organic compounds",
"Organic sodium salts",
"Carbenes",
"Fluorides"
] |
76,861,296 | https://en.wikipedia.org/wiki/Yamada%E2%80%93Watanabe%20theorem | The Yamada–Watanabe theorem is a result from probability theory saying that for a large class of stochastic differential equations a weak solution with pathwise uniqueness implies a strong solution and uniqueness in distribution. In its original form, the theorem was stated for -dimensional Itô equations and was proven by Toshio Yamada and Shinzō Watanabe in 1971. Since then, many generalizations appeared particularly one for general semimartingales by Jean Jacod from 1980.
Yamada–Watanabe theorem
History, generalizations and related results
Jean Jacod generalized the result to SDEs of the form
where is a semimartingale and the coefficient can depend on the path of .
Further generalisations were done by Hans-Jürgen Engelbert (1991) and Thomas G. Kurtz (2007). For SDEs in Banach spaces there is a result from Martin Ondrejat (2004), one by Michael Röckner, Byron Schmuland and Xicheng Zhang (2008) and one by Stefan Tappe (2013).
The converse of the theorem is also true and called the dual Yamada–Watanabe theorem. The first version of this theorem was proven by Engelbert (1991) and a more general version by Alexander Cherny (2002).
Setting
Let and be the space of continuous functions. Consider the -dimensional Itô equation
where
and are predictable processes,
is an -dimensional Brownian Motion,
is deterministic.
Basic terminology
We say uniqueness in distribution (or weak uniqueness), if for two arbitrary solutions and defined on (possibly different) filtered probability spaces and , we have for their distributions , where .
We say pathwise uniqueness (or strong uniqueness) if any two solutions and , defined on the same filtered probability spaces with the same -Brownian motion, are indistinguishable processes, i.e. we have -almost surely that
Theorem
Assume the described setting above is valid, then the theorem is:
If there is pathwise uniqueness, then there is also uniqueness in distribution. And if for every initial distribution, there exists a weak solution, then for every initial distribution, also a pathwise unique strong solution exists.
Jacod's result improved the statement with the additional statement that
If a weak solutions exists and pathwise uniqueness holds, then this solution is also a strong solution.
References
Probability theorems
Stochastic differential equations | Yamada–Watanabe theorem | [
"Mathematics"
] | 498 | [
"Theorems in probability theory",
"Mathematical theorems",
"Mathematical problems"
] |
76,862,447 | https://en.wikipedia.org/wiki/Probability%20of%20superiority | The probability of superiority or common language effect size is the probability that, when sampling a pair of observations from two groups, the observation from the second group will be larger than the sample from the first group. It is used to describe a difference between two groups. D. Wolfe and R. Hogg introduced the concept in 1971. Kenneth McGraw and S. P. Wong returned to the concept in 1992 preferring the term common language effect size. The term probability of superiority was proposed by R. J. Grissom a couple of years later.
The probability of superiority can be formalized as . (D. Wolfe and R. Hogg originally discussed it in the inverted form ). is the probability that some value () sampled at random from one population is larger than the corresponding score () sampled from another population.
Examples
McGraw and Wong gave the example of sex differences in height, noting that when comparing a random man with a random woman, the probability that the man will be taller is 92%. (Alternatively, in 92 out of 100 blind dates, the male will be taller than the female.)
The population value for the common language effect size is often reported like this, in terms of pairs randomly chosen from the population. Kerby (2014) notes that a pair, defined as a score in one group paired with a score in another group, is a core concept of the common language effect size.
As another example, consider a scientific study (maybe of a treatment for some chronic disease, such as arthritis) with ten people in the treatment group and ten people in a control group. If everyone in the treatment group is compared to everyone in the control group, then there are (10×10=) 100 pairs. At the end of the study, the outcome is rated into a score, for each individual (for example on a scale of mobility and pain, in the case of an arthritis study), and then all the scores are compared between the pairs. The result, as the percent of pairs that support the hypothesis, is the common language effect size. In the example study it could be (let's say) .80, if 80 out of the 100 comparison pairs show a better outcome for the treatment group than the control group, and the report may read as follows: "When a patient in the treatment group was compared to a patient in the control group, in 80 of 100 pairs the treated patient showed a better treatment outcome." The sample value, in for example a study like this, is an unbiased estimator of the population value.
Equivalent statistics
An effect size related to the common language effect size is the rank-biserial correlation. This measure was introduced by Cureton as an effect size for the Mann–Whitney U test. That is, there are two groups, and scores for the groups have been converted to ranks.
The Kerby simple difference formula computes the rank-biserial correlation from the common language effect size. Letting f be the proportion of pairs favorable to the hypothesis (the common language effect size), and letting u be the proportion of pairs not favorable, the rank-biserial r is the simple difference between the two proportions: r = f − u. In other words, the correlation is the difference between the common language effect size and its complement. For example, if the common language effect size is 60%, then the rank-biserial r equals 60% minus 40%, or r = 0.20. The Kerby formula is directional, with positive values indicating that the results support the hypothesis.
A non-directional formula for the rank-biserial correlation was provided by Wendt, such that the correlation is always positive.
See also
Pairwise comparisons
Condorcet winner criterion
Intransitive dice
References
Superiority | Probability of superiority | [
"Physics",
"Mathematics"
] | 772 | [
"Wikipedia categories named after physical quantities",
"Probability",
"Probability and statistics",
"Physical quantities"
] |
76,863,523 | https://en.wikipedia.org/wiki/Pelota%20%28boat%29 | A pelota was an improvised rawhide boat used in South and Central America for crossing rivers. It was similar in some respects to the coracle of the British Isles or the bull boat of North America, but it had little or no wooden framework or internal supporting structure, often relying entirely on the stiffness of the hide and the packing of the cargo to keep it open and afloat. Thus, the hide could be carried about on horseback and set up quickly in an emergency, a commonplace rural skill. The vessel was towed by an animal, or by a human swimmer gripping a cord with the teeth, who had to be careful not to swamp it, women being considered particularly dexterous. Pelotas could convey substantial loads—around a quarter of a ton was common—and even small artillery pieces. They continued to be used well into the 20th century.
Necessity
There were few bridges in these regions and rivers had to be forded or, if too deep, crossed in a boat, which might well be unavailable. To cross a river in an emergency e.g. when swollen by torrential rains or during a military campaign, travellers on horseback had to employ such means as were to hand. They were unlikely to be carrying timber, which in some regions e.g. the treeless pampas might be hard to procure. Ox-hides were common, however, and many travellers were in the habit of carrying one under their saddle. (The native recado is a saddle applied in multiple superposed layers, one of which is a large square sheet of rawhide.)
Wrote botanist Augustin Saint-Hilaire: though he was reluctant to entrust his rich collection of specimens to this means of conveyance.
Construction
A sun-dried rawhide is inherently rather stiff, and tends to curve preferentially with the hairy side outwards. The legs were cut off to form a roughly rectangular structure and tied at the four corners to increase its curvature.
In some cases a refinement was employed. Since animal hides were habitually dried by staking them out on the ground, they came with peg-holes along the margins. By passing a cord through these eyelets, the curvature could be further enhanced - like tightening a purse-string. The vessel has been compared to the gigantic water-lily of the Amazon. Martin Dobrizhoffer, a Jesuit missionary in Paraguay, recorded that the four sides were raised "like the upturned brim of a hat", a distance of about 2 spans. Sometimes, a few sticks were inserted for internal support, but this was not usually necessary, or always possible.
If no cowhide was available, one might be procured by slaughtering an animal on the spot and skinning it. Since this hide lacked stiffness, however, it was necessary to vary the construction. The skin was stuffed with, and tied around, a bundle of straw, and only served as a rudimentary float.
Stiffness
If the hide was allowed to get wet through, it tended to become soft and pliable, hence useless. Then it was necessary to dry it out, or to use bracing sticks if these could be found.
Félix de Azara, a Spanish colonial official whose duties compelled him to travel through remote regions and who often used the pelota to cross rivers, complained in his travel diary that torrential rains not only caused flooding but gradually made the pelota useless.
It was said that if a pelota should take too long to cross a river, as might happen if the towing swimmer grew tired, or lost his hold, the hide would soften up and the vessel might sink.
Propulsion
The hide boat was towed across the river, either by a swimmer pulling a cord with his teeth, or by a bullock, or by holding onto the tail of a horse. In the Mato Grosso a second swimmer helped to guide it and push it from behind.
The French traveller de Moussy, who rode very extensively over Argentina, wrote:
Several other sources indicate it was an common rural skill.
Professional pelota towers
The Spanish Empire established a mail service linking Buenos Aires in the Atlantic world with Lima in the Pacific. Posts were set up at intervals along this 3,000 mile route where fresh horses could be obtained and there was (very) basic sleeping accommodation. They were often beside rivers. At each place a postmaster was put in charge who was supposed to keep at least 50 horses; he or she got no salary but was rewarded with valuable legal privileges. Private voyagers were encouraged to travel with the mail, being forbidden to take their own horses.
Where the rivers were too deep to be forded the postal service appointed pasadores (passers) whose function was to carry passengers and mail across in pelotas. Pasadores were not allowed to charge much for the mail but were able to recoup themselves from the private travellers. Thus, at some places there were official pelota towers - persons who swam across rivers and pulled the boat with their teeth - whose charges were regulated by law.
The most notable crossing was at the Río del Pasage or Pasaje (today called the Juramento River), which lay on the road between Tucumán and Salta. It could be forded quite easily in the dry season, but when the waters rose it grew wide and deep, with strong currents and eventually, turbulent waves. An artillery officer wrote that the river brought down logs that endangered pelota and swimmer alike; the latter had to be adept to dodge them. He recorded that the service was still functioning in 1833; a bridge would have been much better, but had not been built owing to bureaucratic inertia. At this spot Indian women were celebrated pelota towers. It is not clear when the service ceased to function, but no bridge was built until 1926.
Women
At this pass the local women were reputed the best swimmers, their dextrous handling of the pelotas being "justly admired"; according to Sir Woodbine Parish they were extremely expert at guiding these "frail barks" across the stream; indeed according to the French geographer Martin de Moussy, in that region "they had a monopoly on this singular industry". Likewise, Domingo Faustino Sarmiento, though he grew up in a completely different part of the country, upon reading James Fenimore Cooper, remarked
Sensation
The sensation of crossing a river in a pelota was described by naturalist Alcide d'Orbigny. It took d'Orbigny an hour to reach the opposite bank. Jesuit missionary Florian Paucke, who was towed across by a 15-year old youth, noticed that his flock was careful to see he was evenly balanced first.
The freeboard was small. "He that sits on it must keep his balance well, for on the slightest movement he will find himself underwater". That the user had to keep absolutely still to avoid rolling the contrivance, or risk sinking, was stressed by more than one author.
Utility
The boat served for transporting clothing and gear that one wanted to keep dry, or cargo which must not get wet e.g. ammunition.
It also served to convey those who could not swim, or would not. In the colonial era, Spanish military commanders, though they knew how to swim, held it was beneath their dignity to strip in front of the common soldiery, and were conveyed by pelota; "scorning the assistance of another person, they impel forwards by two forked boughs for oars". The Rodrigues Ferreira expedition to the Mato Grosso () drew indigenous people taking their children across in pelotas, propelled by pairs of women.
In the tropical Brazil they could be used for rivers that, though fordable, contained dangerous fish.
A pelota could carry two men. Azara wrote that it could easily carry a load of 16 to 25 arrobas (180 to 280) kilos. Azara felt it was safer than a native canoe, and so did Father Dobrizhoffer. Military stores and even (small) artillery pieces could be conveyed across rivers. During the Paraguayan War they were used by a Brazilian reconnaissance expedition in the Pantanal.
As noted, the postal service in colonial and newly independent Argentina appointed official pelota towers. Some of them took the mail across rivers a mile or more across.
General Manuel Belgrano recalled taking a small revolutionary army across the Corriente River in 1811 with nothing but two bad canoes and some pelotas. The river was about a cuadra (80 metres) wide, and unfordable. He noted that most of his men knew how to use a pelota, implying that it was standard rural knowhow.
Not all countrymen knew how to swim, however: it depended on the region. The cavalry troopers of General Paz were from the Province of Corrientes, where everyone did. Crossing a river at night, holding on to the manes or tails of their swimming horses - their arms, ammunition, uniforms and saddles safely dry in pelotas, which they had improvised from rawhide saddle blankets - they surprised and defeated the enemy at the Battle of Caaguazú.
Origins and diffusion
Its origin is uncertain, but it may have pre-dated the Columbian exchange. Some have denied this, arguing that the indigenous peoples lacked domestic animals that could provide a large, strong hide. Another view is that they sewed several small camelid hides together: after the Spanish introduced cattle and horses, this became unnecessary.
James Hornell thought that pelota knowledge spread with human migration along the eastern seaboard of South America and inland. There is evidence it was known to an indigenous people of Patagonia who had never seen a Spaniard.
In the 1890s it could be found in most parts of Brazil, and in Central America.
Even in the 20th century the pelota could be found
Classification
The use of inflated skins as swimming-floats (whence, raft-supports) is ancient, and widely distributed in many human cultures. However the floats are intended to be airtight, for which purpose the skin should be removed from the animal with as few incisions as possible, and must be made wet and pliable.
The pelota, on the other hand, was an open boat that resembled the coracle of the British Isles or the bull boat of North America, but lacked the internal supporting framework of those vessels, except insofar as a few sticks might be added as bracing. (Unlike the pelota, the hide of the bull boat was soft and pliable, and was applied to the supporting wicker framework with hair side facing inwards.) Since the pelota was not a permanent structure but a recourse, it can also be thought of as a skilled voyaging procedure rather than a boat.
In the classification of McGrail, the pelota together with the Mongol hide boat (below) seem to stand in a class of their own, since both were made from a single hide and kept to shape by the internal pressure of the cargo.
Mongolian parallel
The nearest parallel in human culture would appear to be the hun-t'o of medieval Mongolia. Iohannes de Plano Carpini, who went there in 1246, said:
Nomenclature
There is no specific word for this vessel. The Spanish word pelota is general, meaning a round object. It is sometimes specified more precisely as pelota de cuero (hide ball), but this can still mean a football. The Dictionary of the Royal Spanish Academy has the verb pelotear, to cross a river on a pelota, but it can also mean to bounce from place to place, a victim of buck-passing bureaucracy.
In Brazil it was also called pelota, but in Bahia it was called banguê in the indigenous language.
In parts of South America the boat was called a balsa but this is an only general word that can include raft or inflatable lifejacket. Amongst the Chiquitos people of Bolivia it was called natae; amongst the Abipones of the Chaco, ñataċ.
Eponym
The city of Pelotas, Brazil (pop. ) is thought to have derived its name from the water craft, used in the 18th century for crossing a local stream.
Footnotes
Sources
History of Central America
History of South America
History of transport
Indigenous boats | Pelota (boat) | [
"Physics"
] | 2,541 | [
"Physical systems",
"Transport",
"History of transport"
] |
76,863,841 | https://en.wikipedia.org/wiki/HD%2018262 | HD 18262 (HR 870, HIP 13679) is an F-type giant or subgiant star located in the constellation Cetus. It has an apparent magnitude of 5.963, which makes it faintly visible to the naked eye. According to the Gaia spacecraft, HD 18262 is located at a distance of and is moving away from Earth at a velocity of 27.4 km/s. Considering the apparent magnitude and the distance, its absolute magnitude is equivalent to 2.79. It belongs to the thin disk population of the Milky Way.
Characteristics
It is an evolved F-type star that has left the main sequence and is now between a giant star and a subgiant, based on its spectral type of F6III-IVs. The star is 1.54 times more massive than the Sun and has expanded to 2 times its size. It is emitting six times the solar luminosity from its photosphere at an effective temperature of 6,400 K, which is around 630 degrees hotter than the Sun's photosphere. The age of HD 18262 is estimated at 1.64 billion years, equivalent to 36% of the Solar System's age. The star is metal-enriched compared to the Sun, the abundance of iron [Fe/H] on its surface is 2.3 higher than that of the Sun, while the oxygen abundance [O/H] is 2.9 times higher. Its B-V color index is 0.437, giving it the yellowish-white color of a F-type star.
The distance to HD 18262, based on information from the Gaia spacecraft, is of . The apparent magnitude of the star is of 5.96m, which is bright enough to be seen to the naked eye under dark sites, far away from light pollution. The absolute magnitude, i.e. its brightness if it was seen at a distance of , is of 2.79. HD 18262 is moving away from Earth at a velocity of 27.38 km/s. It is part of the thin disk population of the Milky Way. Its orbit around the galaxy has a low eccentricity of 0.06 and its distance from the galactic center varies from 7.14 to 8.11 kiloparsecs (23,280 to 26,440 light-years).
No debris disks have been detected around this star as of 2016 and no exoplanets have been detected around it as of 2012. A 2019 study analysed the possibility of HD 18262 hosting a giant planet, in five ensembles, analysing five different compositions. The highest possibity was in the second ensemble, where the planet would be formed by volatiles, lithophiles, and sderophiles. In this case, the possibility is of 23%. HD 18262's habitable zone is located at a mean distance of 2.44 astronomical units from it.
Notes
References
F-type stars
Subgiant stars
Giant stars
Cetus
0870
WISE objects
018262
2MASS objects
TIC objects
013679 | HD 18262 | [
"Astronomy"
] | 635 | [
"Cetus",
"Constellations"
] |
76,865,988 | https://en.wikipedia.org/wiki/Minimum%20effort%20game | In Game theory, the minimum effort game or weakest link game is a game in which each person decides how much effort to put in and is rewarded based on the least amount of effort anyone puts in. It is assumed that the reward per unit of effort is greater than the cost per unit effort, otherwise there would be no reason to put in effort.
Examples
On an island, each person tries to build barriers to protect an island from flooding. Because even a single failed barriers causes the whole island to flood, the flood protection is determined by the weakest barrier.
An airport ground crew must complete all their tasks before an airplane can take off. As a result, the time spent is based on the slowest member of the ground crew.
Nash equilibria
If there are players, the set of effort levels is , it costs each player dollars to put in one unit of effort, and each player is rewarded dollars for each unit of effort the laziest person puts in, then there are pure-strategy Nash equilibria, one for each , with each player putting in the same amount of effort , because putting more effort costs more money without extra reward, and because putting less effort reduces the reward earned.
There are non pure Nash equilibria, given as follows: each player chooses two effort levels and puts in units of effort with probability and units of effort with probability .
In practice
The amount of effort players put in depends on the amount of effort they think other players will put in. In addition, some players will put more effort than expected in an attempt to get others to put in more effort.
References
Game theory
Mathematical economics | Minimum effort game | [
"Mathematics"
] | 333 | [
"Applied mathematics",
"Game theory",
"Mathematical economics",
"Game theory game classes"
] |
76,866,914 | https://en.wikipedia.org/wiki/Sikidy | Sikidy is a form of algebraic geomancy practiced by Malagasy peoples in Madagascar. It involves algorithmic operations performed on random data generated from tree seeds, which are ritually arranged in a tableau called a and divinely interpreted after being mathematically operated on. Columns of seeds, designated "slaves" or "princes" belonging to respective "lands" for each, interact symbolically to express ('fate') in the interpretation of the diviner. The diviner also prescribes solutions to problems and ways to avoid fated misfortune, often involving a sacrifice.
The centuries-old practice derives from Islamic influence brought to the island by medieval Arab traders. The is consulted for a range of divinatory questions pertaining to fate and the future, including identifying sources of and rectifying misfortune, reading the fate of newborns, and planning annual migrations. The mathematics of include the concepts of Boolean algebra, symbolic logic and parity.
History
The practice is several centuries old, and is influenced by Arab geomantic traditions of Arab Muslim traders on the island. Stephen Ellis and Solofo Randrianja describe as "probably one of the oldest components of Malagasy culture", writing that it most likely the product of an indigenous divinatory art later influenced by Islamic practice. Umar H. D. Danfulani writes that the integration of Arabic divination into indigenous divination is "clearly demonstrated" in Madagascar, where the Arabic astrological system was adapted to the indigenous agricultural system and meshed with Malagasy lunar months by "adapting indigenous months, , to the astrological months, ". Danfulani also describes the concepts in of "houses" (lands) and "kings in their houses" as retained from medieval Arabic astrology.
Most writers link the practice to the "sea-going trade involving the southwest coast of India, the Persian Gulf, and the east coast of Africa in the 9th or 10th century C.E." Though the etymology of is unknown, it has been posited that the word derives from the Arabic sichr ('incantation' or 'charm'). was of central importance to pre-Christian Malagasy religion, with one practitioner quoted in 1892 as calling "the Bible of our ancestors". A missionary report from 1616 describes one form of using tamarind seeds, and another using fingered markings in the sand. The early colonial French governor of Madagascar Étienne de Flacourt documented in the mid-17th century:
The "infiltration" of Malagasy kingdoms by Antemoro diviners, and Matitanana's role as a place for astrological and divinatory learning, help to explain the relatively uniform practicing of across Madagascar.
Origin myths
Mythic tradition relating to the origin of "links [the practice] both to the return by walking on water of Arab ancestors who had intermarried with Malagasy but then left, and to the names of the days of the week" and holds that the art was supernaturally communicated to the ancestors, with Zanahary (the supreme deity of Malagasy religion) giving it to Ranakandriana, who then gave it to a line of diviners (Ranakandriana to Ramanitralanana to Rabibi-andrano to Andriambavi-maitso (who was a woman) to Andriam-bavi-nosy), the last of whom terminated the monopoly by giving it to the people, declaring: "Behold, I give you the , of which you may inquire what offerings you should present in order to obtain blessings; and what expiation you should make so as to avert evils, when any are ill or under apprehension of some future calamity".
A mythic anecdote of Ranakandriana says that two men observed him one day playing in the sand. In fact he was practicing a form of worked in sand called . The two men seized him, and Ranakandriana promised that he would teach them something if they released him. They agreed, and Ranakandriana taught them in depth how to work the . The two men then went to their chief and told him that they could tell him "the past and the future—what was good and what was bad—what increased and what diminished." The chief asked them to tell him how he could obtain plenty of cattle. The two men worked their and told the chief to kill all of his bulls, and that "great numbers would come to him" on the following Friday. The chieftain, doubting, asked what would happen if their prediction didn't come true, and the two men promised they would pay with their lives. The chief agreed and killed his bulls. On Thursday, thinking he'd been duped, he prematurely killed the first man of the two who'd told him about the divinatory art. On Friday, however, "vast herds" came amidst heavy rain, actually filling an immense plain in their crowd. The chieftain lamented the 's wrongful execution and ordered for him a pompous funeral. The chieftain took the second man as his close adviser and friend, and trusted the forever afterwards. The British missionary William Ellis recorded in 1839 two idiomatic expressions used in Madagascar that come from this story: "Tsy mahandry andro Zoma" () is said of someone extremely impatient, and heavy rainshowers falling in rapid succession are called "sese omby" ().
Rites and practitioners
The divination is performed by a practitioner called an , (), , or (derived from the Arabic anbia, meaning 'prophet') who guides the client through the process and interprets the results in the context of the client's inquiries and desires. As part of an 's formal initiation into the art, which includes a long period of apprenticeship, the initiate must gather 124 and 200 (Entada sp.) or (tamarind) tree seeds for his subsequent ritual use in .
writes that, at least among the Sakalava, a man must be 40 years old before learning and practicing , or he risks death. Before beginning to study, a student practitioner must make incisions at the tips of his index finger, his middle finger, and his tongue, and put within the incisions a paste containing red pepper and crushed wasp. This paste impregnates the fingers that will move the seeds of the and the tongue that will speak their revelations with the power to decipher the . Once this is done, he leaves at dawn to search for a (Entada chrysostachys) tree. Upon finding it, he throws his spear at its branches, shaking the tree and causing its large seed pods to fall. During this act, some say: "When you were on the steep peak and in the dense forest, on you the crabs climbed, from you the crocodiles made their bed, with their paws the birds trod on you. Whether you are suspended in the trees or buried, you are never dried up nor rotten." In 1970, Decary reported that the salary paid by an apprentice to his master is "not very high": up to five francs, plus a red rooster's feather.
Some are considered specialists, dealing only with areas of inquiry and resolution within their expertise. In the process of divination, the relates interactively to the client, asking new questions and discussing the interpretation of the seeds. Alfred Grandidier estimated in the late 19th century that roughly one in three Malagasy people had a firm grasp on the art; by 1970 Raymond Decary wrote that the number of was now more limited, and the common knowledge of how to operate and read the was now more basic, with masters of becoming more rare.
and
also provide guidance on how to avoid the misfortune divined in the subject's fate. Solutions include offerings, sacrifices, charms (called ), stored remedies, or observed (taboos). The resolution often comes in the form of the ritual disposal of a symbolic object of misfortune, called the : for example, if the predicts the death of two men, then two locusts should be killed and thrown away as the . William Ellis compares this practice to the ancient Jewish scapegoat. Other objects can be trivial, such as "a little grass", some earth, or the water with which the patient rinses his mouth. If the is ashes, they are blown from the hand to be carried off by the wind; if it is cut money, it is thrown to the bottom of deep waters; if a sheep, it is "carried away to a distance on the shoulders of a man, who runs with all his might, mumbling as he goes, as if in the greatest rage against the , for the evils it is bearing away." If it is a pumpkin, it is carried away a short distance and then thrown on the ground with fury and indignation. The disposal of a may be as simple as a man standing at his doorway, throwing the object a few feet away, and saying the word "". Ellis reports the following for various sources and manifestations of evil:
A divine offering, called a , is also prescribed by the . The may consist of a combination of beads, silver chains, ornaments, meats, herbs, and the singing of a child. Other objects include "a young bullock which just begins to bellow and to tear up the earth with his horns", fowl, rice mixed with milk and honey, a plantain tree flush with fruit, "slime from frogs floating on the water", and a groundnut called . amulets and bracelets may continue to be worn after the cause of their prescription, effectively becoming .
Recovery without adherence to divined prescription and is believed "almost impossible". William Ellis recorded in 1838 that, though the application of indigenous remedies was most common, some patients had lately been instructed as part of the resolution to ask the local foreign missionaries for medicine.
Occasions and questions for
Problems and questions for divined resolution via include the selection of a day on which to do something (including taking a trip, planting, a wedding, and the exhumation of ancestral corpses), whether a newborn child's destiny is compatible with its parents and thus whether it ought to be cared for by another family, the finding of a spouse, the finding of lost objects, the identification of a thief, and the explanation for a misfortune, including illness or sterility.
Raymond Decary writes that the is consulted "in all circumstances", but especially:
In cases of illness, which are understood to be either punishments or warnings from supernatural powers due to the transgression of a (taboo), or poisonings or curses (called ) from other humans.
Before undertaking a journey, in order to divine an auspicious day for travel.
To acquire wealth or foresee the growth of herds (gold prospecting and panning must take place on a day selected by the ).
For all questions relating to women, including whether a potential bride has a fate aligned with her suitor's.
In order to cast a bad spell on someone.
To search for or track down thieves.
The kind and color of sheep to be sacrificed in a wedding procession is also divined by . Among the forest-dwelling Mikea people, is used "to direct the timing of residential movements to the forest ()".
William Ellis describes two ritual occasions for relating to infants: the declaring of the child's destiny, and the "scrambling" ceremony.
As one of the "first acts" following a child's birth, the child's father or close relative consults the local , who works the in order to read the child's destiny. When a child's destiny is declared to be favorable, "the child is nurtured with that tenderness and affection which nature inspires, and the warmest gratulations are tendered by the friends of the parents."
The "scrambling" ceremony, which only occurs with firstborn infants, takes place two or three months after the child's birth on a day divined by the to be lucky or good. The child's friends and family gather, and the child's mother is decorated with silver chains on her head. If the infant is a boy, the father carries him, along with some ripe bananas, on his back. In a rice pan, a mixture is cooked, consisting of the fat from a zebu ox's hump, rice, milk, honey, and a grass called . One lock, called the ('evil lock') is cut from the left side of the child's head and thrown away, "in order to avert calamity". A second lock, called the ('the fortunate lock'), is cut from the right side, and added to the mixture in the rice pan. The mélange is mixed well and held up in its pan by the youngest girl of the family, at which point the gathered (especially the women) make a rush for its contents. It is believed that those who obtain a portion of the mixture are bound to become mothers. The scramble also takes place with bananas, lemons, and sugarcane. The rice pan is then considered sacred, and cannot be removed from the house for three days, "otherwise the virtue of those observances is supposed to be lost".
Incantation
To "awaken" the seeds in his bag as well as his own verbal powers, the incants to the gods or earth spirits in attempt to constrain the gods/spirits to tell the truth, with emphasis on "the trickiness of the communicating entities, who misle[a]d if they [can]", and orates the practice's origin myth. As he incants, the turns the seeds on a mat eastward with his right hand. One Merina incantation quoted by Norwegian missionary Lars Dahle reads:
When practicing the , Sakalava diviners work with a fragment of hyaline quartz in front of their seeds, which is set out before the seeds are produced from their sack.
Arranging the seeds
After his incantation, the takes a fistful of awakened seeds from his bag and randomly divides the seeds into four piles. Seeds are removed two at a time from each pile until there is either one seed or two seeds remaining in each. The four remaining "piles" (now either single seeds or pairs) become the first entries in the first column of a (tableau). The process is repeated three more times, with each new column of seeds being placed on the to the left of the previous. At the end of this, the array consists of four randomly-generated columns of four values (each being either one seed or two) each. The generated data represented in this array is called the (). There are 65,536 possible arrays. From the data, four additional "columns" are read as the rows across the 's columns, and eight additional columns are generated algorithmically and placed in a specific order below the four original columns.
Algorithmically-generated columns
Columns 9–16 of the are generated using the XOR logical operation (), which determines a value based on whether two other values are the same or different. In , the XOR operation is used to compare values in sequence across two existing columns and generate corresponding values for a third column: two seeds if the corresponding values are identical across the pair, and one seed if the values are different. The rules for generating a column from the XOR operation are (with o representing one seed, and oo representing two):
The first 12 columns are generated algorithmically from pairs of adjacent columns in the randomly-generated (the four-by-four grid of seeds representing eight datasets across its four columns and four rows). The last four columns (12–16) of the are derived from the algorithmically-generated columns, with column 16 operating on the first and fifteenth column as a pair.
For example, the first value of column 9 is determined by comparing the first values of columns 7 and 8. If they are the same (both one seed or both two seeds), the first value of column 9 will be two seeds. If they are different, the first value of column 9 will be one seed. This operation iterates for each pair of corresponding values in columns 7 and 8, creating a complete set of values for column 9. Column 10 is then generated by applying the XOR operation between the values in columns 5 and 6. Similarly, column 11 is generated from columns 3 and 4, and column 12 from columns 1 and 2.
Columns 13-16 are generated in the same manner, performing the XOR operation on ascending pairs of the algorithmically-generated columns, starting with columns 9 and 10 (to generate column 13) and ending with columns 15 and 1 (to generate column 16).
Checks
The performs three algorithmic and logical checks to verify the 's validity according to its generative logic: one examining the whole , one examining the results of combining some particular columns, and one parity check examining only one column. First, the checks that at least two columns in the are identical. Next, it is ensured that the pairs of columns 13 and 16, 14 and 1, and 11 and 2 (called "the three inseparables") all yield the same result when combined via the XOR operation. Finally, it is checked that there is an even number of seeds in the 15th column—the only column for which parity is logically certain.
Each of these three checks are mathematically proven valid in a 1997 paper by American ethnomathematician Marcia Ascher. Verification through the use of Microsoft Excel was achieved and published by Gomez et al. in 2015.
Divination
Once the has checked the , his analysis and divination can begin. Certain questions and answers rely on additional columns beyond the prepared sixteen. Some of these columns are read spatially in patterns across the existing 's data, and some are generated with additional XOR operations referring to pairs of columns within the secondary series. These new columns can involve "about 100 additional algorithms".
Each column making up the has a distinct divine referent:
There are sixteen possible configurations of seeds in each column of four values. These formations are known to the diviner and identified with names, which vary regionally. Some names relate to names of months. For many , the formations are associated with directions. The eight formations with an even number of seeds are designated as "princes", while the eight with an odd number of seeds are "slaves". Each slave and prince has its place in a square whose sides are associated with the four cardinal directions. The square is divided into a northwestern "Land of Slaves" and a southeastern "Land of Princes" by a diagonal line extending from its northeastern corner to its southeastern corner. Despite their names, each "Land" contains both slaves and princes, including one migrating prince and one migrating slave that move directionally with the sun, such that the migrators belong to different lands depending on the time of day at which the is performed. The migrators are in the east from sunrise to 10 AM, in the north from 10 AM to 3 PM, and in the west from 3 PM to sunset. is never performed at night, and thus the migrators are never in the south.
The power to see into the past or future is greater in in which all four directions are represented, and most powerful in with four directions represented but with one direction having only one representative. These are called ('-unique'). Beyond being powerful arrangements for divination, represent a particular abstract interest to , who seek to understand them and the data which generate them as an unsolved intellectual challenge. Knowing many leads to personal prestige for the , with discovered examples being posted on doors and spread among diviners by word of mouth.
Divination of the refer to hierarchies of power relating to position and class of figures. "Princes are more powerful than slaves; figures from the Land of Princes are more powerful than those from the Land of Slaves; slaves from the same land are never harmful to one another; and battles between two princes from the Land of Princes are always serious but never end in death."
In divinations relating to illness, the client and creator columns being the same indicates that there will definitely be recovery; if the client and ancestors columns are the same, the illness is due to some discontent on the part of the ancestors; and if the client and house columns are the same, the illness is the same as one that has previously ended in recovery. The relationship between the client and spirit columns is directly referent to illness. If the client is a slave of the east and the spirit is a prince of the south, the client is dominated by the illness, and thus the illness is divined to be serious—but not fatal, because both the east and the south are in the Land of Princes. If the client is a prince of the north (in the Land of Slaves), and the spirit a prince of the south (in the Land of Princes), there would be a difficult battle with a significant chance of the client dying.
If the ninth and fifteenth columns are the same, a bead must be offered as a , called (). If the first and fourth are the same, then a piece of a tree that grows in the villages (not in the fields) must be offered. If the values of the tenth and fifteenth columns added together and subtracted by two equal the values of the first, a stone (called , ) is thrown, retrieved, and carefully preserved by a friend or relation, and so not lost.
The most exceptionally hopeless and severe outcome in a is each value in the first four columns (and thus in the entire tableau) being two seeds. This is called the "red ".
A study computer-simulating the algorithmic generation and objective initial interpretation (according to Sakalava tradition) of the 65,536 possible arrangements of found that, assuming a male client and an inquiry about an illness' cause, the divined cause of illness would be sorcery 21.1% of the time, witchcraft 16.5% of the time, for 9.6%, the village chief for 2.6%, the contamination of food with dirt (which may involve carelessness or evil intentions) for .8%, ancestors for .7%, and undetermined for 48.7%.
Figures
The following are the most common names and meanings for the sixteen geomantic figures of the . Names that also refer to lunar months are marked with a '☾'.
Related traditions
Other Malagasy methods of divination include astrology, cartomancy, ornithomancy, extispicy, and necromantic dream-interpretation.
African sixteen-figure divinatory traditions
Aside from Arabic geomancy, a number of African divination methods using sixteen basic figures have been studied, including Yoruba Ifá cowrie-shell divination, also known by its Fon name Fa and the Ewe and Igbo name Afa. African diasporic populations in Latin America have retained the practice, with the tradition being called Ifa among Afro-Cubans, Afro-Brazilians, and Afro-Haitians. Umar H. D. Danfulani records a breadth of sixteen-figure divinatory traditions across Africa:
Ifá – from Yoruba culture
Fa – from Fon culture; same tradition as Ifá
Afa – from Igbo and Ewe cultures; same tradition as Ifá
Pa; Pe – from Chadic speakers of the Jos Plateau
Noko – from Jukun and Kuteb cultures
Eba – from Ekoi culture
Agbigba – from Igbira and Okun cultures
Efa – from Ekoi culture
Eva – from Isoko culture
Ominigbon; Ogwega; Iha Ogwega – from Bini (Edo) culture
Hakata – "from Zaire and Angola to South Africa"; "bone casting/throwing"; originating from the court circles of Mwene Mutapa (present-day Zimbabwe) and "in the southern Congo river-basin empires"
– from Malagasy culture
See also
I Ching
References
Notes
Geomancy
Culture of Madagascar
Divination
Algebra of random variables
Mathematics and culture
Mathematics and mysticism
Algorithms
Boolean algebra
Logic
Islam in Madagascar | Sikidy | [
"Mathematics"
] | 5,032 | [
"Boolean algebra",
"Algorithms",
"Mathematical logic",
"Applied mathematics",
"Fields of abstract algebra"
] |
76,867,333 | https://en.wikipedia.org/wiki/NGC%205098 | NGC 5098 are a binary pair of distant galaxies located in Canes Venatici constellation. They are made up of one Type E elliptical galaxy, PGC 46529 or NGC 5098 NED01 located east and one Type ES-0 lenticular galaxy, PGC 46515 or NGC 5098 NED02 located west. Both galaxies are located 559 million light-years away from the Solar System and were discovered on April 29, 1827, by John Herschel.
Characteristics
NGC 5098 belongs to the NGC 5098 galaxy group which is located some 560 million light-years away. They are the central galaxy pair, first identified by Ramella et al. 1995 "their group 80." NGC 5098 NED01 is the brighter and larger of the two, showing optical magnitudes of MB = −21.131 and MV = −22.097, as compared to MB = −20.845 and MV = −21.770 for NGC 5098 NED02, which the magnitudes were calculated from Sloan Digital Sky Survey by Adelman-McCarthy and converted to Johnson filter system via the relations provided by Smith et al.
NGC 5098 NED01 hosts an extended radio source, B2 1317+33 which was detected at several frequencies. A study showed there is evidence of gas swooshing and active galactic nucleus (AGN) heating up which the most likely contributor is the nearby galaxy, NGC 5098 NED02 which is being stripped of its gaseous atmosphere. Significant cavities are present in the central region, which two distinctive bubbles are located north and northeast. They are similar to X-ray observations of other galaxies, groups and clusters. These are formed when active galactic nucleus (AGN) jets push into local ICM, evacuating cavities and creating bright rims of X-ray emission from displaced gas.
A plume of emission is seen extending northeast from NGC 5098 NED01, exhibiting a spiral arm morphology which originates east from the galaxy and wrapping around to the north. This presence of a feature indicates NGC 5098 NED01 is indeed interacting with NGC 5098 NED02.
Apart from that, there is a sharp surface brightness to west, southwest and south, which is approximately 28 kpc from the central AGN of NGC 5098 NED01. It appears to go eastwards and define the outer boundaries of the arm, adding to the overall impression of the spiral pattern in diffuse emission. The edges are quite similar to features that are seen from cold fronts generated by gas sloshing in observations and simulations of galaxy clusters and groups.
A study shows that NGC 5098 NED02 does not show any traces of associate emission in X-rays, implying it was stripped of gas. It is possible NGC 5098 NED02 after being ram-pressured stripped and passing east of NGC 5098 NED01 might have circled around it and now moving east, creating a conical wake in diffuse emission.
References
5098
Discoveries by John Herschel
Canes Venatici
Lenticular galaxies
Elliptical galaxies
2MASS objects
Astronomical objects discovered in 1827
Principal Galaxies Catalogue objects
MCG objects | NGC 5098 | [
"Astronomy"
] | 650 | [
"Canes Venatici",
"Constellations"
] |
76,867,498 | https://en.wikipedia.org/wiki/TOPS%20System | Premia Spine TOPS System is an FDA-approved mechanical implant that serves as an alternative to lumbar interbody fusion surgery after decompression. It was developed by Impliant and commercially launched by Premia Spine.
Surgical procedure
The TOPS System is a unitary implant composed of two titanium plates connected by an interlocking flexible articulating core. It has metal arms connecting horizontally to pedicles with four polyaxial screws. The device can be implanted after a standard decompression by removing the lamina and medial facets in a "posterior arthroplasty" procedure. The TOPS System replaces the bony and soft tissue removed during spinal decompression surgery and implants them at the affected spine segment to aid the patient's flexibility.
Uses
It is designed to treat patients diagnosed with common degenerative spinal diseases, including lumbar spinal stenosis, spondylolisthesis, and other facet joint conditions. One of the differences between the TOPS System and traditional fusion surgery is that the TOPS device allows the patient physical stability and a greater range of movement in all directions.
History
Premia Spine developed the TOPS System and initiated a US trial to compare it with the traditional transforaminal lumbar interbody fusion (TLIF) procedure. Under the Investigational Device Exemption (IDE) study by the FDA, the system was available to a limited number of U.S. patients at select hospitals and institutions.
The U.S. Food and Drug Administration (FDA) granted a breakthrough device designation in March 2021, expediting the review process, and later approved the device in 2023.
Research
Studies highlighted its ability to preserve spine biomechanics, measuring effects on disc strain and bulge. Pain and quality of life improvements were quantitatively assessed using the Visual Analog Scale (VAS), Oswestry Disability Index (ODI), and Short Form 36 (SF-36). X-rays, CT scans, and MRIs were used to monitor the implant for adverse events or changes.
A 2012 study presented in Barcelona found that one in four elderly patients who had lumbar spinal fusion for lumbar spinal stenosis (LSS) or spondylolisthesis needed a second spinal surgery within two years. Additionally, nearly half of these patients were readmitted to the hospital due to complications. Comparatively, Premia Spine's follow-ups over five years in Belgium and Israel suggest that the TOPS System yields significantly better outcomes, with a preoperative complication rate under five percent.
In March 2021, Premia Spine received FDA breakthrough device designation for its Tops facet arthroplasty system.
In July 2021, Jared Ament presented the clinical and economic evidence supporting the TOPS facet arthroplasty system at the Spine Summit, San Diego, demonstrating its cost-effectiveness compared to TLIF for treating spondylolisthesis and spinal stenosis.
In November 2021, its intermediate clinical study results, presented at the Society for Minimally Invasive Spine Surgery (SMISS) supported the use of the TOPS System for lumbar spinal stenosis and degenerative spondylolisthesis.
In June 2022, a study published in the Journal of Health Economics and Outcomes Research demonstrated that the TOPS System offers significant health and societal benefits compared to TLIF in treating degenerative spondylolisthesis and stenosis.
In September 2022, the journal Operative Neurosurgery published a single-center study evaluating its TOPS System for lumbar spinal stenosis and degenerative spondylolisthesis. The paper "Mobility-Maintaining Arthroplasty of the Lumbar Spine with the Second-Generation TOPS System" by Werner Lack, Hans Paul Kutschera, and Josef Krugluge found that the TOPS facet replacement can relieve leg and back pain while maintaining nearly normal range-of-motion for four years without causing adjacent segment disease. The study also noted that the TOPS System uniquely helps patients maintain natural sagittal balance, offering new options for non-fusion treatment of degenerative spondylolisthesis and spinal stenosis.
FDA Approval Study
Premia Spine received FDA approval to start an IDE trial of the TOPS System with 300 to 500 patients across up to 40 U.S. centers, randomizing participants into TOPS (67%) or fusion (33%) arms. The trial aims to compare the efficacy of TOPS versus TLIF in stabilizing one lumbar level (L2-L5) after decompression in patients with moderate lumbar spinal stenosis and Grade 1 spondylolisthesis, including conditions like thickened ligamentum flavum or scarred facet joints.
In September 2022, Dr. Dom Coric and colleagues published a study in the Journal of Neurosurgery Spine, which demonstrated that the TOPS System, a motion-preserving treatment for lumbar stenosis with degenerative spondylolisthesis, outperformed TLIF in clinical success rates.
The FDA concluded, as part of its PMA approval process and commercial release of the TOPS System, that the TOPS group demonstrated a clinically meaningful and substantial advantage over the Fusion control group, with 77% of subjects randomized to the TOPs group achieving composite clinical success, compared to 24% of subjects randomized to the fusion control. Based on these results, the TOPS System was deemed to be superior to the Fusion control with respect to composite clinical success while maintaining equivalent safety.
References
Medical devices | TOPS System | [
"Biology"
] | 1,131 | [
"Medical devices",
"Medical technology"
] |
76,868,055 | https://en.wikipedia.org/wiki/Landau%20derivative | In gas dynamics, the Landau derivative or fundamental derivative of gas dynamics, named after Lev Landau who introduced it in 1942, refers to a dimensionless physical quantity characterizing the curvature of the isentrope drawn on the specific volume versus pressure plane. Specifically, the Landau derivative is a second derivative of specific volume with respect to pressure. The derivative is denoted commonly using the symbol or and is defined by
where
Alternate representations of include
For most common gases, , whereas abnormal substances such as the BZT fluids exhibit . In an isentropic process, the sound speed increases with pressure when ; this is the case for ideal gases. Specifically for polytropic gases (ideal gas with constant specific heats), the Landau derivative is a constant and given by
where is the specific heat ratio. Some non-ideal gases falls in the range , for which the sound speed decreases with pressure during an isentropic transformation.
See also
Landau damping
References
Fluid dynamics | Landau derivative | [
"Chemistry",
"Engineering"
] | 194 | [
"Piping",
"Chemical engineering",
"Fluid dynamics"
] |
76,868,613 | https://en.wikipedia.org/wiki/HD%2032356 | HD 32356, also designated as HR 1624, is an astrometric binary located in the northern circumpolar constellation Camelopardalis, the giraffe, near β Camelopardalis. The visible component is faintly visible to the naked eye as an orange-hued star with an apparent magnitude of 5.99. Gaia DR3 parallax measurements imply a distance of 557 light-years and it is currently drifting closer with a heliocentric radial velocity of . At its current distance, HD 32356's brightness is diminished by an interstellar extinction of 0.29 magnitudes and it has an absolute magnitude of +0.23.
The visible component has a stellar classification of K5 II, indicating that it is an evolved K-type bright giant that has ceased hydrogen fusion at its core and left the main sequence. It has 1.18 times the mass of the Sun but at the age of 4.27 billion years, it has expanded to 30.67 times the radius of the Sun. It radiates 300 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of . HD 32356 A is metal deficient with an iron abundance roughly half of the Sun's and it spins too slowly for its projected rotational velocity to be measured accurately.
References
K-type bright giants
Astrometric binaries
Camelopardalis
BD+60 00857
032356
023766
1624
00286710338 | HD 32356 | [
"Astronomy"
] | 304 | [
"Camelopardalis",
"Constellations"
] |
76,869,031 | https://en.wikipedia.org/wiki/Linda%20Poots | Linda Poots (March 25, 1929 – July 10, 2015) was an Estonian zoologist and journalist known for her work with bats. She was the longtime editor of the Estonian nature magazine Eesti Loodus.
Biography
Linda Poots was born in 1929 in Tartu, Estonia.
After high school, she attended the University of Tartu, where she began studying bats. She then studied zoology at Moscow State University, graduating in 1952.
From 1948 onward, Poots made pioneering scientific observations of bats hibernating in Estonian caves. She went on to author many papers on bats in her country. At her urging, bat hibernation sites at Piusa and near Tallinn were protected by the Estonian Soviet Socialist Republic in the 1980s.
From 1952 to 1957, she taught in the Department of Zoology and Entomology at the Estonian Academy of Agriculture in Tartu, now the Estonian University of Life Sciences.
She was a co-founder and the longtime editor in chief of the nature magazine Eesti Loodus, from 1957 until her retirement in 1984. She wrote numerous articles on zoology and travel for this and other publications, and worked as an editor and translator of books on nature.
In 1966, Poots became a founding member of the Estonian Nature Conservation Society.
After retiring from Eesti Loodus, Poots worked in the Tartu University Library from 1984 to 1999, helping classify zoological and medical literature.
Poots married fellow scientist Viktor Masing in 1952. The couple's jointly written travelogue Tuhat tutvust tundrast kõrbeni was published in 1970. She also frequently collaborated with their son, biologist .
She died in 2015 at age 86.
References
1929 births
2015 deaths
Estonian women journalists
Estonian women scientists
Estonian zoologists
Scientists from Tartu
University of Tartu alumni
Moscow State University alumni
Women science writers | Linda Poots | [
"Technology"
] | 371 | [
"Women science writers",
"Women in science and technology"
] |
76,869,123 | https://en.wikipedia.org/wiki/NGC%203800 | NGC 3800 is an intermediate spiral galaxy located in the constellation Leo. Its speed relative to the cosmic microwave background is 3,653 ± 24 km/s, which corresponds to a Hubble distance of 53.9 ± 3.8 Mpc (~176 million ly). NGC 3800 was discovered by German-British astronomer William Herschel in 1784.
NGC 3799 and NGC 3800 are two gravitationally interacting galaxies and appear in Halton Arp's Atlas of Peculiar Galaxies under the symbol Arp 83. Halton Arp describes these as an example of galaxies by presenting a bridge of matter between them and having a high surface gloss.
The luminosity class of NGC 3800 is II and it has a broad HI line.
To date, four non-redshift measurements give a distance of 42.125 ± 1.162 Mpc (~137 million ly), which is well outside the Hubble distance values. Note, however, that it is with the average value of independent measurements, when they exist, that the NASA/IPAC database calculates the diameter of a galaxy and that consequently the diameter of NGC 3800 could be approximately 32.8 kpc (~107,000 ly) if we used the Hubble distance to calculate it.
NGC 3800 group
The galaxy NGC 3800 is part of a group of galaxies named after him. The NGC 3800 group has at least 16 members. Other New General Catalog galaxies in this group are NGC 3768, NGC 3790, NGC 3799, NGC 3801, NGC 3802, NGC 3806, NGC 3827 and NGC 3853. Other galaxies in the group are UGC 6631, UGC 6653, UGC 6666, UGC 6794, MCG 3-30-33 and MCG 3-30-38.
Abraham Mahtessian also mentions the existence of this group, but only the galaxies NGC 3768, NGC 3790, NGC 3801 and NGC 3827 appear there. The galaxy NGC 3853 appears in Mahtessian's article, but under another entry where it forms a galaxy pair with UGC 6666, designated as 1139+1618 (CGCG 1139.7+1648). Similarly, the galaxies NGC 3799 and NGC 3800 are also listed under another entry in this article as a pair of galaxies.
The NASA/IPAC database indicates that NGC 3800 is possibly a field galaxy, that is, it does not belong to a cluster or group and is therefore gravitationally isolated. Scientists have concluded that this is most likely not the case.
See also
List of NGC objects (3001–4000)
Atlas of Peculiar Galaxies
External links
NGC 3800 at SIMBAD
References
Intermediate spiral galaxies
Peculiar galaxies
Leo (constellation)
3800
085
36197
+03-30-039
Astronomical objects discovered in 1784
Discoveries by William Herschel | NGC 3800 | [
"Astronomy"
] | 600 | [
"Leo (constellation)",
"Constellations"
] |
76,869,282 | https://en.wikipedia.org/wiki/New%20York%20Architectural%20Terra-Cotta%20Company | The New York Architectural Terra-Cotta Company was a manufacturer of architectural terracotta based in Queens, New York, U.S.
History
Beginning in the 1870s, architectural terracotta grew in popularity in the United States after architects were drawn to its adaptability for various aesthetic styles and its inherent fireproof qualities. The initial companies to find success were the Chicago Terra Cotta Works and the Perth Amboy Terra Cotta Company, but New York real estate magnate Orlando B. Potter saw an opportunity for a company based closer to New York City to succeed and founded the New York Architectural Terra-Cotta Company with his son-in-law Walter Geer in 1886.
They recruited James Taylor, a ceramicist often described as "the father of architectural terracotta" in the United States, to act as superintendent of the new company's factory in Ravenswood, New York. Less than three months after the company began producing terracotta the entire factory was destroyed by fire. Taylor announced they would rebuild immediately and temporary sheds were built. A new factory, with an automatic sprinkler system, was built and operational in a few months and the company's rebirth was hailed by the community as "Phoenix-like."
In 1892 the company constructed an office building, separate from its manufacturing facility, designed by architect Francis H. Kimball. As was often the case at the time the building was designed to showcase the various products the company was capable of producing, with a Renaissance and Tudor Revival design incorporating terracotta panels, chimney pots, and clay roof tiles.
The company was the fourth largest employer in Long Island City by 1915 and remained successful into the 1920s. A second manufacturing site was built in Old Bridge, New Jersey and the company went bankrupt in 1928–1929.
After dissolution
Richard Dalton, who had been president of the company from 1919 to 1928, formed the Eastern Terra Cotta Company in 1931 and used both of the New York Architectural Terra-Cotta Company's facilities. This new company remained in operation until the mid-1940s, after which the 1892 office was used by Dalton for his construction company. When he died in 1968 the Queens property was sold to Citibank, which demolished the remaining manufacturing works.
Despite opposition from Citibank and Queens borough president Donald Manes, the 1892 building was designated a New York City Landmark in an unusually fast application process in 1982. Afterwards it drew increasing attention for its unique architecture and in 1999 it was purchased by Stuart Match Suna, president of Silvercup Studios. Historic preservationists were initially happy about this purchase due to Suna's wife being an architect on the Landmarks Commission, but Suna did not make efforts to maintain the structure until forced to by lawyers from the Landmarks Commission. In the 2020s the building underwent restorations to the interior and exterior of the structure.
Notable projects
The company produced architectural terracotta for many prominent buildings in and around New York City, including the Lincoln Building, the Corbin Building, the Schermerhorn Building, the Old Grolier Club, the Montauk Club, Carnegie Hall, and The Ansonia.
Gallery
See also
Architectural terracotta
Glazed architectural terra-cotta
Atlantic Terra Cotta Company
References
1886 establishments in New York (state)
1929 disestablishments in New York (state)
American companies disestablished in 1929
Ceramics manufacturers of the United States
Companies based in Queens, New York
Defunct manufacturing companies based in New York City
Manufacturing companies established in 1886
Terracotta
Manufacturer of architectural terracotta | New York Architectural Terra-Cotta Company | [
"Engineering"
] | 714 | [
"Manufacturer of architectural terracotta",
"Architecture"
] |
76,870,890 | https://en.wikipedia.org/wiki/NGC%203799 | NGC 3799 is a barred spiral galaxy located in the constellation Leo. Its speed relative to the cosmic microwave background is 3,659 ± 24 km/s, which corresponds to a Hubble distance of 54.0 ± 3.8 Mpc (~176 million ly). NGC 3799 was discovered by British astronomer John Herschel in 1832.
NGC 3799 and NGC 3800 are two gravitationally interacting galaxies and appear in Halton Arp's Atlas of Peculiar Galaxies under the symbol Arp 83. Halton Arp describes these as an example of galaxies by presenting a bridge of matter between them and having a high surface gloss.
The luminosity class of NGC 3799 is II and it has a broad HI line. According to the SIMBAD database, NGC 3799 is a LINER galaxy, that is to say a galaxy whose nucleus presents an emission spectrum characterized by broad lines of weakly ionized atoms.
To date, a non-redshift measurement gives a distance of approximately 47 Mpc (~153 million ly). This value is far outside the Hubble distance values. Note, however, that it is with the average value of independent measurements, when they exist, that the NASA/IPAC database calculates the diameter of a galaxy.
NGC 3800 group
NGC 3799 is part of a group of galaxies that has at least 16 members which make up what is commonly known as the NGC 3800 group. Other galaxies in this group are NGC 3768, NGC 3790, NGC 3800, NGC 3801, NGC 3802, NGC 3806, NGC 3827 and NGC 3853. The other galaxies in the group are UGC 6631, UGC 6653, UGC 6666, UGC 6794, MCG 3-30-33 and MCG 3-30-388.
Abraham Mahtessian also mentions the existence of this group, but only the galaxies NGC 3768, NGC 3790, NGC 3801 and NGC 3827 appear there. The galaxy NGC 3853 appears in Mahtessian's article, but under another entry where it forms a galaxy pair with UGC 6666, designated as 1139+1618 (CGCG 1139.7+1648). Similarly, the galaxies NGC 3799 and NGC 3800 are also listed under another entry in this article as a pair of galaxies.
See also
List of NGC objects (3001–4000)
Atlas of Peculiar Galaxies
External links
NGC 3799 at SIMBAD
References
Barred spiral galaxies
Leo (constellation)
3799
Astronomical objects discovered in 1832
Discoveries by John Herschel | NGC 3799 | [
"Astronomy"
] | 542 | [
"Leo (constellation)",
"Constellations"
] |
76,871,048 | https://en.wikipedia.org/wiki/Vanja%20Br%C4%8Di%C4%87 | Vanja Brčić is a Croatian amateur astronomer.
He is an IT specialist who runs a computer company and is involved in robotics. He was also a collaborator on the robotic telescope in Višnjan.
Together with Željko Anderić, Korado Korlević, Damir Matković, and Petar Radovan, Brčić contributed to the revival of the observatory in Višnjan after the crisis following the breakup of Yugoslavia.
The Minor Planet Center credits him with the discovery of two asteroids in 1995, both discovered in collaboration with Korado Korlević.
References
Discoverers of asteroids
Croatian astronomers
Date of birth unknown
20th-century astronomers | Vanja Brčić | [
"Astronomy"
] | 134 | [
"Astronomers",
"Astronomer stubs",
"Astronomy stubs"
] |
76,872,783 | https://en.wikipedia.org/wiki/NGC%206365 | NGC 6365 is a pair of spiral galaxies in the constellation Draco. It consists of two galaxies, PGC 60174 to the south, and PGC 60171 to the north. These two galaxies are also designated respectively by the NASA/IPAC database as NGC 6365A and NGC 6365B. This pair of galaxies was discovered by German astronomer Lewis Swift in 1884.
NGC 6563A
NGC 6563A is the northern counterpart of NGC 6563, and is a barred spiral galaxy. Its coordinates are 17h 22m 43.8s and 62° 09 57.9. Its speed relative to the cosmic microwave background is 8,413 ± 4 km/s, which corresponds to a Hubble distance of 124.1 ± 8.7 Mpc (~405 million ly).
The luminosity class of NGC 6365A is III-IV and it has a broad HI line. It is an active galaxy (AGN) of type Seyfert 2.
With a surface brightness equal to 14.00 mag/am^2, we can qualify NGC 6365A as a low surface brightness galaxy (LSB). LSB galaxies are diffuse (D) galaxies with a surface brightness less than one magnitude lower than that of the ambient night sky.
To date, nearly fifteen measurements not based on redshift give a distance of 111.469 ± 31.088 Mpc (~364 million ly), which is within the values of the Hubble distance.
Supernovae
Three supernovae have been observed in NGC 6365A:
SN 2003U was discovered in NGC 6365A on January 27, 2003, by Scottish astronomer Tom Boles. This supernova was of typeIa.
SN2016ino (typeIc-BL, mag. 17.8) was discovered on 26 November 2016 by Ron Arbour.
SN2020qim (typeII, mag. 18.6) was discovered on 26 July 2020.
NGC 6563B
NGC is the southern counterpart of NGC 6563, and is a spiral galaxy. However, the NASA/IPAC database indicates that it is Magellanic in type. Its coordinates are 17h 22m 43.5s and 62° 10 25.4. Its speed relative to the cosmic microwave background is 7,975 ± 4 km/s, which corresponds to a Hubble distance of 117.6 ± 8.2 Mpc (~384 million ly). The luminosity class of NGC 6365B is IV-V and it has a broad HI line. It also contains regions of ionized hydrogen.
Galaxy interaction
The pair of galaxies that make up NGC 6563 appear in Halton Arp's Atlas of Peculiar Galaxies under the designation Arp 30. Arp describes NGC 6365 as a spiral galaxy with an overdeveloped arm, but this has been recently confirmed by astronomers to be false. In the image used by Arp, PGC 60171 (NGC 6365B) appears to be part of PGC 60174 and to be one galaxy. But, they are actually two separate galaxies. According to redshift-based measurements, NGC 6365A is the most distant galaxy. However, given the uncertainties in the measurements, NGC 6365B could be the most distant galaxy. The image taken by the telescope at the Mount Lemmon observatory does not allow us to decide. There is no publication that is only speculative about their position and also about their interaction.
See also
List of NGC objects (6001–7000)
Atlas of Peculiar Galaxies
Lists of galaxies
List of supernovae
References
External links
NGC 6563 at SIMBAD
Draco (constellation)
6365
Interacting galaxies
Spiral galaxies
Barred spiral galaxies
Seyfert galaxies | NGC 6365 | [
"Astronomy"
] | 787 | [
"Constellations",
"Draco (constellation)"
] |
76,873,102 | https://en.wikipedia.org/wiki/Manganese%20nitrides | Manganese nitrides are salts of manganese and the nitride ion. Four of these compounds are stable at atmospheric pressure. The most important is Mn3N2, which catalyzes nitrogen fixation and is a high-temperature antiferromagnet. The others are Mn6N5–6, Mn4N, and Mn2N. The compounds generally form as surface layer during combustion of manganese metal in nitrogen or ammonia gas, and homogenous samples can be difficult to obtain.
Formation
The compounds generally form from combustion of manganese metal in nitrogen or ammonia gas, but as a passivating surface layer; consequently homogenous samples are difficult to obtain. A sufficiently activated manganese sponge results from distillation of manganese amalgam. As described in 1894, a sponge is essential to Mn2N synthesis: manganese powder, if used instead, instead absorbs excess nitrogen, although the resulting nitrogen-rich salt anneals with manganese metal to the correct stoichiometry.
Alternatively, manganese(II) chloride undergoes a non–self-propagating solid state metathesis with magnesium nitride at 550 °C to form Mn3N2; higher temperatures or differently-sized cations give Mn2N instead. Excess molten sodamide at 240 °C reduces manganese oxides to nitrides, with the final product dependent on stoichiometry, through the following reaction.
3 Mn2O3 + 9 NaNH2 → 2 Mn3N2 + 9 NaOH + N2 + 3 NH3
The waste sodium hydroxide selectively dissolves in an aqueous ethanol wash. Manganocene ammonolyzes at 700 °C to give Mn3N2. Manganese azides decompose when heated to give Mn3N2 or Mn6N5–6 and nitrogen gas.
Structures and properties
Several manganese nitrides are stable at atmospheric pressure. The most important is Mn3N2, which catalyzes nitrogen fixation and is a high-temperature antiferromagnet. Other salts include Mn6N5–6, Mn4N, and Mn2N. Splat quenching may also form a metastable Mn8N that decomposes without diffusion. In general, no binary compounds of manganese and nitrogen are known in which manganese exhibits a formal oxidation state higher than Mn2+, but manganese does form a wide variety of homoleptic nitrido complexes and ternary salts, with oxidation states ranging from Mn+ to Mn+6.5; indeed, the stablest homoleptic complex is Li7MnN4.
Except for Mn6N5–6, manganese nitrides are generally stable against hydrolysis, but act as Brønsted bases in concentrated acid.
Nitrogen-doped manganese experiences a slight freezing point depression, with a eutectic point estimated near 1213 °C and 4 at% nitrogen. Further addition of nitrogen increases the melting point to roughly 1270 °C.
Mn4N is an antiperovskite superlattice with Pearson symbol cP5 and space group Fmm, the same structure as an iron nitride homologue. The cell period is 0.3864 nm, and each nitrogen atom is very nearly at the center of the cell. Any defects present are believed to be of Frenkel type. It is the only truly ferromagnetic phase in the manganese-nitride system, with a Curie temperature around 470 °C. However, dissolved hydrogen in the compound is believed to slightly increase the Curie point. The compound metamorphosizes at 890 °C to the hexagonal close-packed Mn2N phase.
Despite the name, Mn2N in fact exhibits substantial variation in its stable composition with temperature, and the formula Mn2N is only accurate near room temperature. It becomes nitrogen-deficient when heated, with composition Mn5–6N above 890 °C. These shifts in composition also correspond to a gradual change in the unit cell, such that the compound has various hexagonal unit cells at high temperatures. At its most nitrogen-rich (and coldest), though, the compound has an 0.5668×0.4909×4.537 nm3 orthorhombic unit cell with space group D. Pbna. It is isostructural with Mo2C.
Mn3N2 is face-centered tetragonal, with Pearson symbol tI6 and space group I4/mmm, analogous to thorium hydride. The unit cell has periods a = 0.42046 nm and c = 1.2131 nm, corresponding to three nearly-cubic unit cells stacked atop each other, but with substantial disorder corresponding to nitrogen vacancies. It is a metallic conductor and a Pauli antiferromagnet, with Néel temperature roughly 645 °C. Around 710 °C, it reversibly decomposes to Mn2N, releasing the excess nitrogen as gas and consuming 25 kJ/mol enthalpy. Likewise, it decomposes in a 400 °C hydrogen atmosphere to a body-centered cubic alloy.
Mn6N5–6 resembles CrN. It is face-centered tetragonal like Mn3N2, but lacks the vacancies that cause such a large fineness ratio in the latter. Instead Mn6N5–6 is nearly cubic. When nitrogen-poor, it has lattice parameters a = 0.42 nm and c = 0.41 nm, but the unit cell dimensions vary substantially with nitrogen content and temperature, and the material becomes truly cubic at 400 °C. Consequently it exhibits substantial crystal twinning. Around 580 °C, it decomposes to Mn3N2 and nitrogen gas, but requires a very high nitrogen vapor pressure (even at lower temperatures) to stabilize the phase. The decomposition is somewhat reversible, recovering Mn6N5.18 upon cooling. Between 150 °C and 325 °C, it undergoes a magnetic phase transition, aligning moments along one symmetry axis; the Néel temperature is then 387 °C.
In principle, a hexagonal MnN monolayer should exhibit very strong spin polarization, thus behaving as a very strong ferromagnet.
See also
Antiperovskite manganese nitride
References
Manganese compounds
Alloys
Nitrogen compounds | Manganese nitrides | [
"Chemistry"
] | 1,313 | [
"Chemical mixtures",
"Alloys"
] |
76,874,049 | https://en.wikipedia.org/wiki/Chain%20boat%20navigation%20on%20the%20Main | Chain boat navigation on the Main was a special type of ship transport on the Main from 1886 to 1936. Along a chain laid in the river, chain boats pulled themselves upstream with several barges attached. The technology of chain shipping replaced the previous practice of towed shipping, in which the ships were pulled by horses.
As the canalisation project progressed upstream, the barrages required for this made chain towage more challenging, particularly due to the extended waiting times at the locks. This led to the emergence of a new competitor in the form of the propeller, which was made possible by the greater depth of the navigation channel. The use of diesel engines made the propeller a profitable option. The use of steam engines for the labour-intensive chain navigation became unprofitable, and this method was completely discontinued in 1936.
History
Before chain boat navigation
The Main River has a relatively gentle gradient. Until the mean water level correction in the middle of the 19th century, the river was a slow-flowing shallow watercourse with numerous loops, bends, islands and, on occasion, several shallow river arms in close proximity to one another. In contrast, the occurrence of strong floods, particularly during the autumn and spring months, resulted in the flooding of areas, the erosion of riverbanks and sedimentation. Conversely, during the summer months, the water level in the channels, which were typically only half a metre deep, decreased to a few centimetres, resulting in the formation of shallows and sandbanks.
Upstream, the ship trains were towed by line riders. A typical train consisted of a chain of wooden vessels, each with a carrying capacity of 15 to 30 tonnes. They usually began with a Frankensau or a market boat and continued via Schelche, Schlumper and Nachen to the smallest vessel, the Ankernachen. The towpath often changed banks before the mouths of the tributaries or before steep slopes. At these points, horses and riders had to cross the navigation channel or be ferried across. Downstream, the ships drifted in the water current. Sails were set when the wind was favourable. The cost of towing the mostly empty or lightly loaded ships was high. Therefore, profit could usually only be made when the fairway was sufficiently deep and with fully loaded ships travelling downstream.
In 1828, the Stadt Frankfurt was the inaugural paddle steamer to traverse the Main between Mainz and Frankfurt. However, the venture was unsuccessful due to design flaws in the steam engine and the challenging navigation conditions in the heavily silted Main estuary. The trials were terminated as early as 1832. It was not until 1841, following the Free City of Frankfurt's accession to the German Customs Union and the completion of the Taunus Railway line from Frankfurt to Wiesbaden, that steam navigation on the Main resumed. However, it was unable to establish itself for several reasons. Firstly, the unfavourable fairways of the Main at low water levels during the summer months presented a challenge for steamboats with their relatively large draught, particularly given that the promised fairway improvements from the Bavarian state were not implemented to the desired extent. Secondly, the railway, which was constructed at the same time, was more efficient than steamships. It was able to travel at faster speeds and had shorter routes. The waterway from Mainz to Schweinfurt was 88 per cent longer. Furthermore, the railway was able to bypass customs offices, eliminating the need for lengthy waiting periods. It was also exempt from customs duties and tariffs, reducing its financial burden. As early as 1858, the unprofitability of steam navigation with paddle steamers led to the discontinuation of this mode of transport.
The time of chain boats on the Main
After navigation on the Main had lost more and more of its transport capacity to the railway and the use of wheeled steam tugs had failed due to the shallow navigation channel of the Main, Heino Held, owner of the Mainz-based forwarding and coal trading company C.J.H. Held & Cie., had the idea of saving navigation by introducing chain tug navigation. On 15 February 1871, he applied to the authorities in Prussia, Bavaria and Hesse for a corresponding licence, encouraged by the companies that had just started up on the Elbe. In 1872, the various states and towns along the Main then established a committee in Aschaffenburg. The committee was supported by Ewald Bellingrath, who had already played a leading role in the introduction of chain navigation on the Elbe and Neckar rivers. The committee discussed the merits of chain shipping and the canalisation of the Main. Mainz, which was part of the Grand Duchy of Hesse, was in favour of chain shipping as it feared that the canalisation of the Main would allow Rhine ships to bring their goods directly to Frankfurt, which would result in Mainz losing its position as a transfer point. Frankfurt, which was then part of Prussia, sought to become a Rhine port and only agreed to the chain once the canalisation to Frankfurt had been completed. The Bavarian state parliament was also opposed to the chain, citing concerns about competition for the Bavarian state railway. Initially, it only approved the chain as far as Aschaffenburg.
In 1885, the Hessian joint-stock company Mainkette-AG was granted a concession to operate chain shipping on the Main and through the Rhine to the port of Mainz. The Mainkette-AG laid the chain and the chain boats were built at the Neckar shipyard in Neckarsulm in 1886. The plans for the construction were provided by the company Gebr. Sachsenberg from Roßlau (Elbe), which had already gained many years of experience with the construction of chain boats and also supplied the entire machinery for travelling with the chain to the Neckar. From the Neckar to the Main, the chain ships could be transported directly by water, which would not have been possible from the Elbe. The chain ships were capable of pulling themselves and up to ten attached barges at speeds of around five kilometres per hour.
The line between Mainz and Aschaffenburg was inaugurated on 7 August 1886. By October of that year, all three chain boats (Mainkette I-III) were operational on this route. The Fränkische Kurier published a review of the early days of chain navigation:
In the following years, Mainkette-AG expanded its fleet of ships with three screw steam tugs. Initially, these were used mainly as feeder boats in Mainz-Kostheim and Frankfurt. However, they were then increasingly used for towing services between Mainz and Frankfurt itself.
In 1892, the Bavarian government granted the Mainkette-AG's repeated request to extend its chain to Miltenberg, subject to the proviso that it could be cancelled at any time. However, just two years later, the Bavarian government passed a law to establish its own chain navigation on the Main, with the chain being extended to Lohr in the summer of 1895. In the absence of its own chain tugs, the Mainkette-AG was authorised to operate on this section of the river in return for a chain usage fee. From 1895 to 1901, the Hessian Mainkette-AG continued to operate its chain boats on the Bavarian sections of the river as far as Miltenberg or Lohr.
In 1898, the Bavarian kingdom established the Königlich Bayerische Kettenschleppschiffahrt-Gesellschaft (KBKS) in Würzburg, which was managed by the Bavarian state railway. The newly established state company was tasked with constructing five chain tug boats, designated K.B.K.S. No. I to V, at the Übigau shipyard in Dresden. The boats were prefabricated at the shipyard, transported by rail to Aschaffenburg, and then riveted together and launched between 1898 and 1900.
The Bavarian state built a shipyard near Schweinheim for maintaining its chain ships. It is located below river kilometre 88.8 between the banks of the Main and the former Mainländebahn railway.
However, following the deployment of all new Bavarian chain boats, the Hessian Mainkette-AG was forced to withdraw from Bavaria. The Königlich Bayerische Kettenschleppschiffahrt-Gesellschaft purchased the chain between Aschaffenburg and Miltenberg from the Mainkette-AG and extended it in the following years: 1900 to Kitzingen, 1911 to Schweinfurt and 1912 to Bamberg. The chain reached its greatest length of 396 kilometres. In 1910 and 1911, three additional boats, designated K.B.K.S. No. VI to VIII, were prefabricated in Übigau and assembled in Aschaffenburg. From 1912, eight Bavarian chain tugs were thus travelling between Aschaffenburg and Bamberg.
The chain boats were mostly only used for travelling uphill. In 1900, the Aschaffenburger Zeitung described the situation of chain navigation as follows:
Following the abdication of King Ludwig III in 1918, the designation K.B.K.S. (Königlich Bayerisches Kettenschiff) was amended to remove the first 'K.' for 'Königlich'. Consequently, the ship number eight was no longer referred to as K.B.K.S.NoVIII, but simply B.K.S.NoVIII. (Bayerisches Kettenschiff Nummero acht). In 1924, the designation was changed to DRG. KS NrVIII (Deutsche Reichsbahn-Gesellschaft Kettenschiff Nummer acht). Following the 1937 takeover by the Deutsche Reichsbahn, the designation was changed to DR.KS NrVIII (Deutsche Reichsbahn Kettenschiff Nummer 8).
The end of chain navigation
As the people of Frankfurt were initially interested in the canalisation of the Main as far as their city, the Bavarian state now showed great interest in the canalisation of the Main as far as Aschaffenburg. All goods, in particular the Ruhr coal required to operate the Bavarian state railways, were to be transported there by ship, stockpiled, stored and distributed. This did not affect the state-owned Bavarian chain shipping company operating upstream on the Main, but the Mainz-based company Mainkette-AG had to bear the consequences. The damming of the river led to a greater water depth and, at the same time, a reduction in the flow speed. In particular, the long tows had to be split up at the locks of the barrages and sluiced separately. This could result in delays of up to five hours, as the barges had to be manhandled into and out of the locks.
The shift in profitability from chain shipping to propeller-driven vessels was significant. With the progressive canalisation of the Main as far as Aschaffenburg in 1921, the Mainkette-AG was only able to use its screw-driven boats economically and ceased tugboat operations entirely in the early 1930s.
In 1935, the Nuremberg Reichsbahn Directorate also had to state the following for the Bavarian route: "The volume of traffic on the chain tugboat service on the Main has declined extraordinarily in the first half of this year [1935] due to competition from screw boats, so that operations have almost come to a standstill and the question of completely closing down the company must be considered." The reason given for this was:
Another disadvantage of chain dragging was the sideways movement of the chain across the river bed, which could result in the chain being pulled into the inside of the bend. This resulted in the chain occasionally dragging large stones into the navigation channel or edging up stones already in place. Furthermore, the chain was not returned to its original position each time it was lifted.
Bavarian chain navigation was completely discontinued in July 1936 and the chain was lifted in 1938. On 14 May 1938, the Fränkische Kurier described the last voyage of a chain boat on the Main:
The name Mainkuh
The chain tow had priority over other ships in front of dangerous river sections. These had to turn round and allow the towed convoy to pass. To warn the other ships, the chain ships emitted a loud whistle signal well in advance. Such a signal was also sounded before ships were coupled or uncoupled. If a towed convoy passed the home harbour of the chain tug or one of the barges, signals were also given. The families of the skippers were aware of the convoy's arrival and were able to provide provisions, clothing, and news via small boats, known as "Nachen." The tooting of the chain boats, which sounded like a loud mooing, and the loud rattling of the chains, reminiscent of a cowshed, led to the common name Mainkuh, or, depending on the dialect and pronunciation, the Lower Franconian Määkuh, Meekuh, Frankfurter Maakuh or Meankuh.
Technical description
The chain boats travelled on a chain laid in the riverbed, which was only fixed in the river at the beginning and end. The bar-less chain consisted of iron links 118 mm long, 85 mm wide and 26 mm thick. The chain's own weight and its natural entanglement with the river bed meant that it could exert a tensile force of around 40,000 newtons (equivalent to around 4,000 kg). Extensions (booms) were attached to the bow and stern of the ship, which could be swung sideways in either direction. The chain was taken out of the river bed via the front boom and guided above deck along the ship's axis to the chain drive in the centre of the ship. Guide rollers ensured that the chain was accurately aligned. From there, the chain ran across the deck to the boom at the stern and back into the river. Thanks to the lateral mobility of the boom and the two rudders mounted fore and aft, it was possible to lower the chain back to the centre of the river, even when the river bent.
Eduard Weiß, writing in the journal of the Association of German Engineers, described the ships as follows: "The appearance of the ship is peculiar in that it is highest in the middle and slopes too much towards the ends to minimise the loss of work caused by the lifting of the towing chain". This shape is typical of all chain tugs and is optimised for shallow water. The deeper the water, the lower the efficiency, as more and more energy is required to lift the chain from the bottom.The chain lasted about 10 to 15 years. Due to the abrasive effect of the sand between the links, the chain broke more frequently. To prevent the chain from being fished up from the bottom using search anchors, catching devices in the form of locking hooks were fitted to the ships' booms to prevent the chain from running away after a chain breakage or while the chain was being repaired.
The chain ships of Hesse
The three Hessian ships, designated Mainkette I-III, had a length above deck of 49.80 metres and a breadth at the waterline of 7.05 metres. Apart from the chain drive in the form of a drum winch, they had no other independent propulsion. These ships were therefore dependent on the chain to move up and down the river. Ships meeting had to pass each other in a complicated manoeuvre. First, the chain had to be opened at shackles (called "chain locks") spaced 400 metres apart in the chain. Using an auxiliary chain and rope, the downstream ship had to leave the chain and anchor. Once the vessel travelling against the current had passed, the downstream vessel could re-enter the chain with a time loss of approximately 45 minutes.
The draught with 20 tonnes of coal on board was 0.60 metres. The ships were powered by an 88 kW (120 hp) steam engine. Typical of this type of ship were two funnels placed side by side. This was because the ship had two boilers, each with one fire. The coal consumption per hour was 3 hundredweights (150 kg).
The Bavarian chain ships
The Bavarian chain boats with the designations K.B.K.S. No. I-V were constructed in Übigau and, at 50 metres above deck (equivalent to 46.80 metres at the waterline), were slightly longer than the vessels of the Mainkette-AG. However, the width at the waterline was smaller at 6.40 metres (width above deck 7.40 metres). With a draught of only 0.56 metres, they had a displacement of 147 cubic metres, which equates to their weight in tonnes. With a propulsion power of 95 kW (130 hp) provided by a steam engine, they were able to pull up to 12 barges.
The Bavarian chain boats, designated K.B.K.S. No. VI-VIII, were slightly longer at the waterline than the previous version, at 48.00 metres. However, the width at the waterline remained unchanged at 6.40 metres. The steam engines on these ships were capable of 80 kW (110 hp) of propulsion power. Until 1924, the chain grip-wheel used for power transmission was manufactured by Bellingrath. Subsequently, a two-wheel chain wheel was used, around which the chain was looped.
A distinctive feature of the Bavarian ships was the incorporation of two water turbines, designed by Gustav Anton Zeuner, which served as precursors to the modern water jet propulsion system. This enabled the ship to be steered and to travel downhill without a chain at a speed of approximately 14 kilometres per hour. The additional drive also permitted directional corrections to be made while travelling on the chain, as well as facilitating turning manoeuvres.
The Bavarian chain ships were equipped with a single chimney. This feature can be folded down if required. The hull was divided into seven compartments, each separated by a watertight bulkhead. The crew consisted of the captain, a helmsman, two sailors, an engineer and two stokers. The sleeping quarters and cabins were situated on the lower deck. The steering platform was covered with a canvas cover and a sun/rain sail was stretched over it. The steering position was subsequently converted into a wheelhouse.
Model ships
A model of a chain boat is on display at the Wörth am Main Maritime and Shipbuilding Museum, along with a piece of the original chain. Additionally, there is a 1:5 scale model of a double winch that winds and unwinds the chain at the touch of a button. A second model of a chain boat is on display in the meeting room of Wörth town hall and can be loaned to other museums and exhibitions if required.
The model of a chain tugboat on display at the local history museum in Elsenfeld allows the chain to be moved on the model. Additionally, the museum displays an original ship's bell from the Royal Bavarian Chain Steamship No. 4 and a piece of the original chain. Please note that the museum is only open a few days a year.
The Museum Stadt Miltenberg and the Schlossmuseum Aschaffenburg also have a model of a chain ship. A piece of the original chain can also be seen in Aschaffenburg.
Another model (a shipyard model of the K.B.K.S. No. I on a scale of 1:25) is in the possession of the DB Museum in Nuremberg. However, this was only rarely exhibited at the museum. Since April 2010, the model has been on permanent loan in the Guild Hall of Aschaffenburg Castle.
The K.B.K.S. No. V chain ship is also available as a 1:250 scale cardboard model.
Germany's last chain ships
The final surviving example of a Main chain ship was on display in the former raft harbour of Aschaffenburg until March 2009. The Määkuh was used as a restaurant and jetty until the advent of the new millennium. The ship's superstructure had been modified to such an extent that it was no longer recognisable as a chain ship. Subsequently, she was moored in the Erlenbach am Main shipyard and has since been docked at the SMA harbour on the left bank of the Main at Main km 91 in Aschaffenburg, where she has remained since October 2009 (see illustration). The vessel has been dismantled and is no longer afloat. In the autumn of 2009, the associations "Technikdenkmal Määkuh" and "AbaKuZ e. V." initiated a campaign to prevent the vessel from being scrapped and to facilitate its subsequent reconstruction in its original form. In 2010, the ship was sold. The ship's hull, with a maximum clearance height of approximately 1.80 metres, was to be used as a café or exhibition space in the immediate vicinity of the castle in the future. However, the city council rejected the plans in 2015. In 2021, the future of the ship remained uncertain. The dimensions of the ship indicate that it belongs to the series K.B.K.S. No. I to V. As a result of its historical significance and exceptional rarity, it was included as a movable monument in Part A – Monuments – Book 71 of the list of monuments – City of Aschaffenburg.
The last remaining example of a chain ship that can be identified as such is the Gustav Zeuner, which was used on the Elbe and is now moored in Magdeburg as a museum ship.
Literature
Berninger, Otto. "Bericht der Reichsbahndirektion Nürnberg vom 7. August 1935 an die Hauptverwaltung der Deutschen Reichsbahn-Gesellschaft". Mainschiffahrtsnachrichten (in German). 11 – via Verein zur Förderung des Schifffahrts- und Schiffbaumuseums Wörh am Main.
Schanz, Georg (1893). Studien über die bayerischen Wasserstraßen. Die Kettenschleppschiffahrt auf dem Main (in German). Vol. 1. Bamberg: Buchner.
Zesewitz, Sigbert; Düntzsch, Helmut; Grötschel, Theodor (1987). Kettenschiffahrt (in German). Berlin: Technik.
Weiß, Eduard (1901). "Die Kettenschlepper der kgl. bayerischen Kettenschleppschiffahrt auf dem oberen Main". Zeitschrift des Vereines Deutscher Ingenieure (in German). 45 (17): 578–584.
Betz, Helmut (1996). Die Mainschiffahrt: vom Kettenschleppzug zum Gelenkverband. Historisches vom Strom (in German). Vol. 12. Duisburg: Krüpfganz.
References
External links
Last journey of the Määkuh pushed by a push boat YouTube
K.B.K.S. No.5 „Technikdenkmal Määkuh“. "Määkuh" technology monument working group.
Boats
Main (river) basin
Water transport
History of transport | Chain boat navigation on the Main | [
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76,874,340 | https://en.wikipedia.org/wiki/Aliceevansviridae | Aliceevansviridae is a family of viruses in the class Caudoviricetes. The family was announced in 2022 and contains three genera (Brussowvirus, Moineauvirus, and Vansinderenvirus), along with several species unassigned to a genus, including SMHBZ8.
Etymology
The family's name, Aliceevans, is in honor of Alice Catherine Evans (1881–1975), an American microbiologist, the suffix -viridae is the standard suffix for virus families.
References
Virus families | Aliceevansviridae | [
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76,874,842 | https://en.wikipedia.org/wiki/CYP76%20family | Cytochrome P450, family 76, also known as CYP76, is a cytochrome P450 family in land plants, related to the biosynthesis of many plant monoterpenes and diterpenes such as 8-hydroxygeraniol, tanshinone and alkannin. The first gene identified in this family is the CYP76A1 and CYP76A2 from the eggplant.
References
Plant genes
76
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"Protein families",
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76,875,263 | https://en.wikipedia.org/wiki/Honda%20V6%20hybrid%20Formula%20One%20power%20unit | The Honda RA6xxH/RBPTH hybrid power units are a series of 1.6-litre, hybrid turbocharged V6 racing engines which feature both a kinetic energy recovery (MGU-K) electric motor directly geared to the crankshaft and a heat energy recovery (MGU-H) electric motor attached via a common shaft to the turbocharger assembly. Developed and produced by Honda Motor Company (and subsequently under their Honda Racing Corporation organisation from 2022) for use in Formula One. The engines have been in use since the 2015 Formula One season, initially run by the then newly re-established McLaren Honda works team. Over years of development, power unit output was increased from approximately 760 to over 1,000 horsepower while utilising the same amount of fuel, as mandated by enforced technical regulations (Fuel Mass Flow Rate limit of 100kg per hour). Teams utilising the engines over the years include McLaren, Scuderia Toro Rosso, Scuderia Alpha Tauri, RB Formula One Team, Red Bull Racing.
List of models
*The engine development freeze was enforced from 2022 in efforts to reduce spending. Power unit performance specifications mounted to cars in first session running of the 2022 season were then locked in until the end of the 2025 season and no performance upgrades could be introduced. However, manufacturers are allowed to bring reliability upgrades during the freeze.
** System output estimates are final readings at season end.
History
The Formula One hybrid engine regulations being introduced in had enticed Honda to make a return as an engine supplier due to the advanced technical challenge and environmentally focused direction. Having planned to enter in the 2016 season in a works partnership with McLaren, then McLaren CEO Ron Dennis, had pushed for Honda to fast track their debut to the 2015 season as their current contract with Mercedes was expiring. Honda had decided to accept the early entry believing they were well on target with their Power Unit concept.
Having entered Formula One in the 2015 season, one year earlier than initially planned, and experiencing difficulty for the first few years with regards to performance and reliability, primarily due to underestimating the technical challenge and being out of the Formula One world for over 7 years, the Honda V6 hybrid engine experienced a stratospheric developmental rise having started as an unreliable and underpowered design to becoming a world championship winning success. Becoming the first manufacturer to win a Formula 1 race with two different teams in the V6 hybrid era, as well as among many other major constructor and driver F1 records. Notably, Max Verstappen and Red Bull Racing, with a record breaking 19 wins in the 2023 Formula One World Championship, beating his own record of 15 the year prior, which itself beat the previous record held by McLaren Honda in the 1980s.
Power units (2015–2025)
RA615H
The RA615H, was Honda's first design for use in the V6 hybrid F1 era, debuting in the 2015 Formula One season powering the McLaren MP4-30. It was highly unique compared to the designs of rivals Renault, Mercedes and Ferrari who had already debuted power units the season prior, and as such, Honda felt its best chance to make up for lost development time was to go aggressive and radical.
The primary focus points of the unit, at the request of McLaren, were extremely compact dimensions and high operating temperature capability that could function with reduced cooling requirements as to aid aerodynamic performance and centre of gravity targets. The unit's turbocharger assembly was a compact but complex axial compressor arrangement with the MGU-H fitted between the turbine and compressor housings, all mounted within the vee of the engine in its entirety. This allowed for a significantly shorter engine compared to the Renault, Ferrari and Mercedes concepts whereby their compressor assemblies all protruded from either ends of the block in varying formats. The induction system, which includes the inlet, filters, intake plenum and variable inlet runners, were all small and ornate in design to fit under the tight bodywork dimensions. This made the entire system compact, but also very complex. The exhaust manifold was a small "log" type design (where one pipe housed ports for each cylinder on either bank), this was very beneficial to packaging requirements and allowed significantly tighter bodywork. The result was an engine that proved to be by far the smallest on the field, earning the nickname, "The Size-Zero", from McLaren, as it gave them the freedom to be aggressive with the body aerodynamics resulting in extremely tight packaging and efficient bodywork with the goal to make significant gains in this area over the competition.
After debuting publicly for the first time in the MP4-30 at the 2015 pre-season test at Jerez, rumours began circulating that the engine was extremely unreliable, heavy on fuel use and significantly down on power. This became evident with the very limited amount of circuit running McLaren Honda could do due to various issues with the engine appearing. It was quickly discovered that although the compact nature of the turbocharger assembly was beneficial to packaging, it proved to be vastly undersized and as such, had poor air compression capabilities which resulted in significantly less power and combustion efficiency potential. The intake system, while also compact, its complexity and compromise in ideal shape, orientation and size also proved too detrimental to performance and reliability. These all had further knock on effects to the hybrid energy side of the power unit, having poor regeneration capabilities. Honda's lack of experience in programming and controlling such a complex power unit made identifying specific issues difficult and time consuming. Additionally, the compact nature of the entire concept seriously hindered the thermal management and vibration severity of the engine, often causing various components to overheat, specifically the MGU-H, with uncontrolled resonances and vibration which led to constant hybrid system failures and terminal engine damage.
Honda maintained these were early teething issues, only discovered after mounting the engine to a moving chassis under racing loads for the first time and they would quickly sort these out. However as the season progressed, reliability issues and the ability to even complete a race distance became such a concern that the engines, already down on power, needed to be run in a reduced power state to lower thermal load in attempt to increase longevity, this severely compromised overall car performance in comparison to the competition. The restrictive "development token" system F1 used at the time slowed development significantly, limiting what developments could be brought forward in season at any given time leading to longer setbacks. Honda's lack of experience and data with the new regulations, fundamental issues with the "Size Zero" engine concept, while also self-admittedly entering the championship too early, were reasons given by Honda themselves for the lacklustre performance.
RA616H
The RA616H made its racing debut in the McLaren MP4-31 in the 2016 Formula One season. This engine, still largely following the "Size Zero" concept of the RA615H, had significant developments in an effort to increase both power and reliability. After conversations with McLaren, it was agreed to allocate more space for the power unit, as such, the engine grew considerably in size. The entire induction system was reworked and raised higher, this allowed their "within vee" compressor assembly to be raised higher which allowed more space for a larger version, this provided more power and also improved heat regeneration for the hybrid system, although was still restricted to mounting within the vee of the engine. The new taller inlet plenum had more space, so larger and more refined inlet runners were developed to better feed the engine and was able to be simplified slightly, so reliability for the variable intake system increased. The exhaust manifold was completely reworked with equal length individual runners which were larger, but far more efficient. The MGU-K had a newer, more efficient magnet assembly which improved battery regeneration. The MGU-H also had revised magnets which were much more heat resistant to help improve reliability issues.
Overall, Honda had made as many changes to the engine as were allowed by the "development token" regulation still imposed by Formula One. Honda made clear that they were aware of the fundamental design restraints the current power unit concept had, but to properly address these issues, changes would need to be made to the token system to allow increased development speed in season.
The engine proved to be much more reliable and McLaren had a far better season, suffering from less engine related retirements and while still lagging behind, were more competitive in terms of outright power. However, there were still fundamental issues that were encountered, with MGU-H reliability, although improved, still far from acceptable levels for both McLaren and Honda themselves. The engine was improved further over the season to try and extract as much potential from the current architecture as possible and aside from reaching a relatively stable and reliable point towards the end of the season, Honda believed the current architecture was at its limit and would need drastic changes to move forward.
Following the issues faced by newcomer Honda and some of the other manufacturers when compared to the class-leading Mercedes units, F1 announced the scrapping of the development token system for the 2017 season onwards, allowing for significantly faster power unit development in the hopes the competition would begin to level out.
RA617H
The RA617H made its racing debut in the 2017 Formula One season powering the McLaren MCL32. With the scrapping of the development token system, Honda moved to make a radical change, no longer restricted by the token system. The result was the RA617H, a completely new design with the most notable change being the reworked turbocharger/MGU-H setup. The new design now split the compressor and turbine housing and mounted each half on either end of the cylinder block protruding out of the vee. The MGU-H remained in the centre of the vee and the entire assembly was connected via one shaft. This increased the length of the engine, however it also allowed a significant lowering of the turbo/MGU-H setup and a greatly increased compressor and turbine size (no longer physically restricted by the bank angle within the vee), this then allowed the induction system above to also be lowered dramatically, which resulted in a much lower height engine with a vastly improved centre of gravity. Its design was totally overhauled, revising the orientation of the variable runners to a longitudinal position, whereas previously they were horizontally placed, opposing each other. This greatly improved the extension range they could operate which improved performance across a much broader RPM range while also simplifying the system which brought improved reliability. In discussion with McLaren, the MGU-K had its geartrain position reversed with a new structure and was now mounted further forward on the PU to better accommodate packaging and bodywork aero design McLaren were pursuing, this also provided a weight reduction and increased reliability. The MGU-H was significantly overhauled along with the new compressor system, now housing higher performance magnets to improve the flux field which improved battery regeneration performance. The combustion system was also completely overhauled, now utilising an experimental system known as Turbulent Jet Ignition or Pre-Chamber Ignition, which greatly increased power and efficiency potential, along with various other internal material changes. All these new technologies being implemented into one engine meant Honda admitted the entire unit was so experimental that it was a "high risk" move and would take time to realise the full potential of several aspects, but one they believed will ultimately provide much greater performance.
As pre-season testing began at Catalunya in Spain, fundamental issues with the power unit were found. The oil tank, which was previously mounted at the front of the engine, was now physically obstructed by the new compressor position and as such was re-designed with an unorthodox shape surrounding the compressor which, after initial running in the new McLaren MCL32 and being exposed to such high-G loads for the first time, was found to cause the oil flow to became unpredictable and restricted, with the engine often losing oil pressure in high load situations. Honda quickly identified the issue and set to work to create a new design tank to combat this, however it would not be ready until the second week of testing. The reasoning put forward for the issue was incorrect fluid dynamic simulation estimates of the lateral loads the 2017 car regulations would produce, which were far higher than expected. In the meantime, the temporary countermeasure was to overfill the oil tank to ensure flow was always available, this came with its own issues however, often overflowing into the intake system and damaging other components. This compromised running significantly and made completing testing programs for both the new engine and new chassis difficult. At the second week of pre-season testing and the revised oil tank fitted, other issues were observed. Again, unprecedented forces from the new 2017 regulation car being transmitted through the power unit, which acts as a stressed member of the car, also brought extreme drivetrain vibrations which caused various ancillary failures and more distressingly, a persistent catastrophic turbo/MGU-H shaft failure. The design of the MGU-H housing for the RA617H saw it cast as part of the cylinder block in efforts to improve strength, however this solution upon malfunction, would often terminally damage the ICE as well. The power unit issues during testing were so numerous that McLaren Honda found themselves changing complete power units endlessly, rather than identifying and fixing issues in an effort to gain as much mileage as possible on the car so chassis testing could be carried out.
Over the season, the engine suffered a severe amount of failures. Honda admitted it was taking longer than hoped to understand how to operate the new engine or come up with a viable long term fix for the vibration and shaft balance issues destroying the MGU-H. The engine was now being run in a state of tune that produced less power than the RA616H it replaced from the year prior for reliability concerns and even with consistent upgrades being provided through the season, progress was initially slow. This tarnished the relationship between Honda and McLaren with both parties showing public frustration with the other. The power unit eventually started to produce signs of progress in the latter half of the season as Honda brought countless updates to the Pre-Chamber Ignition system with varying jet orifice counts and sizes to gain a better understanding in its operation and various other improvements to related systems and finally reliability visibly began to improve and Honda was able to turn the power back up to where it produced more power than the RA616H it replaced.
RA618H
The RA618H was developed for the 2018 Formula One season and was the first Honda engine to power Scuderia Toro Rosso in the STR13. It was a much more mature development of Honda's brand new architecture introduced with the RA617H the year prior.
The power unit benefitted from Toro Rosso being significantly more relaxed on the engines dimension requirements than McLaren, with the team asking Honda to build the engine how they saw fit and they would build the car around it. Immediately, the engine was significantly more reliable than the RA617H, only suffering three engine related retirements over the entire season. The troublesome MGU-H was totally redesigned with input from Honda's aerospace division HondaJet, lending their significant experience in precision turbofan design. The MGU-H shaft and attached turbines spin at up to a regulation limit 125,000rpm and with the unique design of the split turbo assembly, getting such a long shaft to be perfectly balanced at such high rotational speeds was paramount to the assembly's reliability. As such, the shaft had its size and shape completely altered, its bearings improved and received an entirely new structural support mechanism which largely eliminated the resonance/vibration issues that affected the previous iteration. The MGU-H rotor was totally redesigned and now housed in a pressurised rotor chamber which further enhanced performance and reliability and received enhanced magnets to improve performance.
Now having more real estate on the car available to work with, the air intake funnel was enlarged and shaped more optimally for improved airflow into the engine, the exhaust manifold was further optimised and routed differently to suit the STR13 bodywork while gaining a net performance improvement, the cooling system designed for use in the STR13 was substantially more effective, the engine received structural reinforcements and material changes to better handle the forces experienced by the new generation cars and as such, the power unit increased in weight slightly, although still remained the lightest of the field. The MGU-K had its bearing supporting structure modified to improve reliability and also received higher efficiency electromagnets.
During the Canadian GP, Honda introduced the "Spec 2" version of the power unit which consisted of changes to the ICE and combustion system, solely in pursuit of performance. The engine proved to deliver a noticeable leap forward in power and it was this power unit that is believed to of pushed Honda ahead of rival Renault in performance and reliability. This performance gain, steep development curve and trajectory, investment into their facilities and drive to win was enough to convince Red Bull Racing to sign Honda as their power unit supplier from the 2019 season to replace Renault.
High Speed or Rapid Combustion
During research and testing in 2018 at HRD headquarters in Sakura, Honda engineers while running a prototype 2019 engine on the dyno, noticed a combustion phenomenon whereby cylinder pressures and power output would skyrocket momentarily before disappearing again. This occurred several times before it was discovered this was due to a mismatch of certain specification parts being fitted on the test engines. This led to Honda implementing a vastly improved quality check process, but it also encouraged a smaller team of engineers to look deeper into this phenomenon.
Red Bull Racing had also requested that Honda bring as many updates to its engines on track as physically possible, regardless of penalties incurred to Red Bull owned Scuderia Toro Rosso, if it would speed up development in preparation for the 2019 season. The result was the "Spec 3" test engine which made its debut at the 2018 Russian Grand Prix. This engine was a prototype for a new kind of combustion process discovered on the dyno's in Sakura after further research and development was undertaken to understand the phenomenon. Dubbed "rapid combustion" by Honda, it is a process in that a significantly more complete yet violent combustion event takes place under certain conditions which drastically improves output and efficiency of the engine.
In a conventional engine, "flame propagation combustion" is utilised, where the flame front within the combustion chamber begins at the spark plug electrode and propagates outward towards the cylinder walls. This propagation takes time to fully occur however, so optimal ignition timing is dictated by the speed of this propagation so that the peak of the combustion event occurs at the most optimal piston position during the power stroke for maximum force to be applied to the crankshaft. Because this event takes time to complete, the energy released is not all occurring at this optimal point so maximum work potential is lost. For example, the ignition timing is usually set for the spark to occur as the piston is still travelling upwards as that will allow for the peak of the combustion event to occur at the optimal piston position (precisely as it begins its downward stroke) for maximum work/power to be exerted on the crankshaft. With advancing it this far (spark beginning too early) however, to compensate for the burn time, can lead to combustion initially working against the piston movement or pre-ignition (detonation before intended), this causes knock and stress on the system and can also reduce power.
With this new combustion process ("rapid combustion"), conditions such as compression ratio and air/fuel mixture are optimised so flames are even-generated around the circumference of the combustion chamber, where self ignition is triggered by the pressure shock from the jet flames fired from the pre-chamber orifices. While the jet flames spread out to the circumference from the centre of the combustion chamber, the other flames spread from the circumference toward the centre, so combustion proceeds significantly more rapidly. This massively increases the burn speed, and so a much larger portion of the energy released occurs at the most optimal piston position during each power stroke, this increased maximum power and efficiency significantly, and due to this increase in burn speed, ignition timing could be more specific and optimised, also removing this small amount of combustion working against the piston on the upward stroke, further increasing the efficiency of the power unit. Combustion of this type allows for a much leaner than typical air/fuel ratio to be used which would otherwise be difficult to ignite in a conventional combustion engine. This process required a substantial increase in compression ratio to be made, and although very beneficial to efficiency, was extremely difficult to control and brought significant increases to cylinder pressures, which affected the durability of the ICE.
The Spec 3 engine was tested in a car for the first time during practice sessions at the Russian Grand Prix, with drivers reporting feeling a substantial increase in power, however there was a lot of vibration and unusual gearbox shift behaviour present. This was largely caused by the difficulty in stabilising the new combustion process during sudden RPM drops experienced during gearshifts. After the practice sessions, Honda refitted the previous Spec 2 engines for qualifying and the race as planned. The engine was found to have gained approximately 40-50hp just with this change initially, which was substantially more than estimations suggested. This increase and the method in which it produced this, pushed the engine past its structural design limits and as such needed further work on the engine to be able to withstand the increased power level, unique combustion process and further synchronisation work with the Red Bull sourced gearbox to smooth out gear change behaviour. The new combustion process was in its infancy and initially very unstable, so required more development time to understand and refine the power unit.
RA619H
The RA619H was the first Honda power unit to be supplied to Red Bull Racing, debuting in the RB15. It was also the first time Honda had supplied two teams in the current hybrid era of Formula One simultaneously, still continuing their relationship with Scuderia Toro Rosso, powering the STR14.
The engine was a further refinement of the initial RA617H engine concept introduced in 2017. Following on from the RA618H, the new engine had a more complete version of the "rapid combustion" process. Honda had refined the calibration and hardware to better utilise the combustion method and fuel partner ExxonMobil had developed a new type of fuel that stabilised the process in time for race debut. The engine had improvements across the board with refinements to the induction and exhaust systems for optimal packaging while bringing performance gains, the MGU-K had refined mechanical components to improve reliability under high temp operation, the electromagnetic internals were largely carried over from 2018. The MGU-H had a new stator, designed to work under increased water temperatures with a smaller radiator, the MGU-H motor now had the ability to be pushed harder in certain high performance engine modes, the connecting shaft was increased in length to accommodate a new larger compressor but the dynamics of this shaft were further improved for reliability.
Throughout this season, Honda focused on improving energy management and calibration to improve driveability and extract optimal performance from the power unit across the season. During the French GP, Honda introduced a new compressor that greatly increased compressor efficiency by improving its aerodynamic performance. At the same time it had discovered a method in the calibration to largely maintain targeted performance during high ambient temperatures and altitudes. For the following race, they implemented these findings for the Austrian GP which is held at over 750m above sea level, where the engine performed faultlessly at high power in high temperatures where rival manufacturers were running into cooling issues. Max Verstappen went on to win this race which he attributes to Honda's constant efforts and willingness to keep pushing the envelope.
By this point, the RA619H's power output was closely matched to the rival Mercedes engine, making up significant ground since Honda's return in 2015.
RA620H
The RA620H was the fourth and final iteration of the engine architecture Honda introduced in 2017, powering the Red Bull Racing RB16 and the Scuderia AlphaTauri AT01 in the 2020 Formula One season.
The new combustion process, discovered in 2018 and fully integrated into the 2019 RA619H, provided substantial power and efficiency gains, however, the massively increased chamber pressure and often unstable detonation under certain conditions came at the cost of durability for the internal combustion engine. For the RA620H, Honda developed a new type of surface plating named "Kumamoto Plating" or "K-Plating". This patented method was applied to the cylinder bore and other high-stress surfaces. This drastically reduced the cylinder wear under high-speed combustion operation, allowing further steps to improve the efficiency and operation of this combustion process.
The 2019 MGU-K and MGU-H underwent strenuous durability and performance testing over the winter break and their limits were identified. So for 2020, the MGU-K was run harder and more aggressively, giving more torque in driving, and more regenerated electricity under engine-braking conditions. A more aggressive regeneration calibration was applied in a newly created operation mode known as "Extra Harvest". This mode allowed for large energy regeneration to occur in a short period, which placed more stress on the unit, so it was used only when most effective. The compressor was enlarged further to increase engine efficiency and the turbine housing was now 3D Printed (additive manufacturing) with Inconel, allowing more complex shapes to be created. Engine ancillaries were refined further to reduce parasitic losses. With the ability to produce components with additive fabrication, the MGU-H housing was also produced with a 3d printer, increasing strength and reducing weight. The ICE's steel pistons were also 3D Printed which allowed for ribs and indentations in places that were not possible when forged and machined, further increasing strength and again reducing weight.
To find more efficiency gains, Honda developed a device named the "Charge Air Cooler 2" or CAC2. Early variants of this were introduced on the 2016 engine and are a major part of the signature "Honda sound" the power units make on deceleration and downshifts. The CAC2 routes compressed air, that would otherwise be vented to the atmosphere, into the combustion chambers of "non-firing" cylinders. This re-routed compressed air has multiple benefits but primarily, it allows additional drive force for the turbine to be stored in cylinders when they are not firing, which has a faux "anti-lag" effect. This can be used to spool the turbo up without using battery power or be used to regenerate more energy with the MGU-H in regeneration mode. Secondly, this compressed air has a cooling effect within the chamber increasing durability and knock resistance.
The RA620H can be viewed as a mid-process example of Honda's usual conservative approach to power units, first ensuring reliability, then switching to an aggressive push to maximise the potential once the reliability is established, and then back to obtaining reliability. Honda believed they saw this switching point in the mid-2019 season and work had begun on a brand new, ground up design (RA621H) planned for introduction within two years.
RA621H
After initially starting to match Mercedes' power unit performance in 2019, the performance step made in 2020 with the M11 EQ Performance power unit, even compared with Honda's own gains, was substantial. This had convinced Honda to accelerate development of its new engine which was originally planned for debut in 2022 along with the new car regulations. The late decision meant they had just six months to complete the engine and have it race ready for the 2021 Formula One season. Honda admitted this would be a monumental challenge and posed a lot of risks, but believed this would be the only way to overtake Mercedes. Team partner Red Bull Racing, after seeing the proposed improvements the new power unit would bring, gave their blessing and as such, the RA621H was born, powering the Red Bull Racing RB16B and the AlphaTauri AT02.
This engine was a drastic change from the previous iterations, with the entire core ICE architecture being redesigned for the first time. The camshaft layout was altered and now significantly more compact, lower down and closer together in the cylinder head. This changed the valve angle and shape of the combustion chamber, increasing the compression ratio of the ICE, lowering it's centre of gravity and altering the airflow characteristics. The cylinder block was now machined from a single piece of new billet alloy as opposed to cast, drastically increasing the blocks strength which allowed the cylinder bore pitch to be reduced, placing the cylinders closer together. These major structural changes created a significant reduction in the overall size of the engine in height, length and width. In discussion with Red Bull Racing and Alpha Tauri, the bank offset was reversed, the induction manifold was further optimised for performance and packaging and the exhaust manifolds were redesigned and became an asymmetric setup being radically different from left to right banks to improve exhaust pulse tuning and better optimise packaging within both cars. The MGU-H had vastly improved magnets and a new insulator, improving the cooling performance while also increasing power and torque output and the MGU-K had its gear ratio revised which further improved regeneration under coasting or braking and overall torque output under motoring, and had a brand new housing which was more resistant to vibration.
With the vastly improved thermal efficiency of the new ICE came a trade-off, a reduction in waste exhaust energy output which negatively impacts turbocharger and hybrid regeneration performance. The key for Honda engineers was to play a balancing act in increasing ICE efficiency and crank power output but without losing too much exhaust heat energy which would harm regeneration potential for the battery. To mitigate the losses, the turbocharger assembly was revised in attempt to more efficiently harvest what was available and the compressor was increased in size again with the compressor wheel having significant changes made to the blades and the turbine itself was also modified.
Carbon Nano Tube (CNT) Energy Store
Honda also introduced a brand new energy store (ES) for the first time, which had been in the developmental phase since 2016. The aim was to create a battery that combined improvements in energy efficiency with significant reductions in weight. The technology utilised in the new ultra-high energy battery cell was revealed to be an in-house Honda developed ES utilising Carbon Nano Tubes (CNT), battery cell electrodes containing carbon particles, and electricity flows through these particles. By filling the spaces between carbon particles with the nanometer-sized, tube-shaped CNTs (with a diameter of one millionth of a millimetre), it is possible to achieve extremely low resistance and enable electricity to flow more freely. Demonstrating significant reductions in resistance and deterioration over its lifespan, the power unit's energy harvesting and deployment characteristics improved substantially. The volumetric output density (Watt per kg) of the new ES introduced in the 12th round of the 2021 season is 1.3 times greater (130% improvement) than that of the ES used in 2020 and 2021. This allowed the cars to have deployable hybrid energy available much more of the time and much faster regeneration capability compared to the rest of the field. As compared to the 2015 Energy Store, even with the dramatic improvement in density and efficiency, the brand new battery is 26% smaller and 15% lighter, which contributes greatly from the perspectives of energy management and optimising vehicle driving performance.
All these changes added up to a power unit that was significantly more powerful and reliable, while becoming even smaller and lighter than the original RA615H "Size-Zero" engine of 2015. This provided massive gains to teams, now able to create more aggressive body packaging which aided aero development. The power unit quickly became the front runner of the field with superior power, energy recovery abilities with outstanding reliability and was a key factor in driving Max Verstappen to his first ever World Drivers Championship in the 2021 season.
RBPTH001
The RBPTH001 is a development of the RA621H designed for use in the 2022 Formula 1 World Championship (and subsequently the 2023 Formula 1 World Championship) powering the Red Bull Racing RB18 and AlphaTauri AT03 in 2022 and the Red Bull Racing RB19 and AlphaTauri AT04 in 2023. It represents the final permitted power unit design change before the engine freeze began on March 1st, 2022.
After Honda's formal F1 exit, the engines remain Honda-developed, produced, assembled, maintained, and trackside supported, and will remain as such until the end of the 2025 season when a new engine era will begin. Honda developed the 2022 RBPTH001 power unit at its research and development centre in Sakura City, Tochigi prefecture, run by Honda’s racing subsidiary, HRC (Honda Racing Corporation).
10% Ethanol fuel (E10) introduced
The main developments of the engine were to accommodate the use of the new E10 fuel and the challenges it brought. The construction of the ethanol molecule means it has a lower calorific value as a combustible component compared to an equivalent volume of petrol, making the combustion process less potent and therefore, power is reduced. This is usually compensated by combusting a larger quantity of fuel (and a corresponding increase of air, usually in the form of increased boost pressure) to make up for the lower energy density, however this is not an option as F1 regulations restrict fuel flow to 100kg/hour, so to regain lost power potential, the engine would need to be pushed harder and made more thermally efficient to extract more of the available fuel energy content.
There are some exploitable beneficial characteristics of ethanol however. The new E10 fuel blend is more resistant to detonation, allowing engines to be run in a higher stress state if well controlled, so for the RBPTH001, along with significant improvements to all the technologies introduced over the past 6 years to the power unit, the result was a major evolution that made even the regulation maximum compression ratio of 18:1 feel restrictive despite it being an enormously high target when Honda first rejoined F1 in 2015. This along with raising the nominal boost pressure, helped to drive combustion efficiency higher and mitigate power losses brought from the lower energy fuel, essentially harnessing more of the available fuel energy to compensate. This greatly increases the stress on the power unit though, with cylinder pressures now the highest they have been. So the combustion chamber and mechanism was further developed to accommodate the new burn characteristics and lower calorific fuel, the bottom end internals were strengthened, and the ignition timing map was altered completely from the 2021 engine. The MGU-H and turbine were re-tuned to better cope with the E10 exhaust gas density change and further unique internal changes to reduce crevice losses in combustion were made. Ethanol also has a higher latent heat of vaporisation than gasoline, so the increased ethanol content brought a charge cooling effect, reducing combustion chamber temperatures, this benefit allowed the previously mentioned changes to be made and allowed Honda to increase the nominal running water temperature of the engine, this meant it required less cooling and provides a further aerodynamic benefit to teams building the car, being able to reduce cooling inlet and outlet sizes.
The crankshaft and cylinder block geometry were adjusted to ensure reliability with the new E10 combustion conditions, while a further development of Honda's Kumamoto plating was applied to the cylinder bores. The resulting power unit weighs slightly more than the RA621H, just from strengthened internal components. Even challenged with the reduced energy content of the new fuel, the 2022 engine achieved a higher thermal efficiency value than the 2021 engine. With road car engines achieving between 20-35%, Honda had achieved a result well over 50%, making the RBPTH001 one of the most power dense and efficient gasoline reciprocating engines ever developed.
RBPTH002
THE RBPTH002 was developed for use in the 2024 Formula One season, replacing the RBPTH001 that was used in the 2022 and 2023 seasons. Currently powering the Red Bull Racing RB20 and Visa Cash App RB VCARB01. With the engine freeze in place since 2022, power unit development has been restricted to reliability improvements only. For 2024, Honda made further improvements to the RBPTH001 to increase the engines durability, this increased the reliability of the power unit with increased racing distance thresholds before degradation began to reduce performance. The gains allowed teams to run the engine in a higher power state (more aggressive engine modes) for longer periods of time without any negative effects. This allows for a more performative power unit during the season. Specific details of the changes have not as yet been disclosed to the public but the changes made were drastic enough to warrant a new designation in the engine series, as the RBPTH002.
Season statistics for hybrid era Honda engines
** Historical record for most wins in a season - Red Bull Racing
References
Engines by model
Gasoline engines by model
V6 Hybrid Formula One Power Unit
Formula One engines
V6 engines
Honda in motorsport
Honda in Formula One | Honda V6 hybrid Formula One power unit | [
"Technology"
] | 7,634 | [
"Engines",
"Engines by model"
] |
76,875,652 | https://en.wikipedia.org/wiki/NGC%207609 | NGC 7609 or known as Arp 150 and HCG 95A, is a large elliptical galaxy located in Pegasus. Its speed relative to the cosmic microwave background is 11,879 km/s, which corresponds the galaxy to be located 554 million light-years away from Earth (169.7 Mpc). NGC 7609 was discovered on October 5, 1864, by Albert Marth and included in Halton Arp's, Atlas of Peculiar Galaxies in galaxies that produces jets.
With a surface brightness of apparent magnitude 14.59, NGC 7609 is classified as a low surface brightness galaxy (LSB). LSB galaxies are diffuse galaxies with surface brightness that is one less magnitude, of the night sky.
A pair of interacting galaxies
A SDSS survey image and from the Hubble Space Telescope, showed that NGC 7609 is interacting with nearby galaxy, PGC 71077 (HCG 95C) whose spiral arms is currently being absorbed by the larger entity. A double-nuclei is present in HCG 95C, which is considered a merger remanent of two disk galaxies. Two tidal tails are also found in NGC 7609 and HCG 95C region, which seems to connect together, and there is a linear bridge between two galaxies indicating nuclear activity is taking place in HCG 95C. From the study written from Vilchez & Iglesias-Paramo in 1998, Hα emission is detected in the nuclei of both galaxies and also the larger tidal tails (the eastern tail).
A long slit spectra of NGC 7609 shows, it exhibits red-shifted H-alpha +[N II] and [S II] emission lines that is indicative to a LINER-type AGN (Active Galactic Nucleus).
From the spatial profiles, this indicates non-nuclear starburst activity triggered by tidal forces while nuclear spectrum indicates non thermal activity. From the further IUE observations of HCG 95C, it presents a featureless continuum with transient outburst captured in one observation, showing galactic emission of red-shifted N v (1240 A) and C IV (1550 A). This result depicts HCG 95C is in the early stages of merging with NGC 7609.
According to another study, it is suggested that a dwarf galaxy might have been created at the tip of the northern tidal tails.
Hickson 95 group
NGC 7609 is a member of Hickson Compact Group 95. There are total of four galaxies in the group, in which the members are PGC 71074, PGC 71077 and PGC 71080. Of all the four galaxies, PGC 71080 (HCG 95B) is a foreground galaxy, as its line-of-sight velocity of 8000 km/s significantly differs from the velocity of the other members per published by Hickson et al.
Presence of ultra-diffuse galaxies around HCG 95
A study mentions there is a detection of 89 candidate ultra-diffuse galaxies (UDGs), around NGC 7609 and HCG 95, in which one is linked with. It is a gas-rich galaxy with H i mass 1.1 x 10 M⊙, detected by Very Large Array, and has a stellar mass of M 1.8 x 10 M⊙. This indicates that UDGs partially overlap with population of nearly dark galaxies found in deep H I surveys. The results show high abundance of blue UDGs in the HCG 95 field is favored by the poor galaxy cluster environment residing in H I-rich large-scale structures.
Supernova
One supernova has been observed in NGC 7609. SN 1973M (type unknown, mag. 19) was discovered by Charles Kowal on 8 June 1973.
References
7609
Pegasus (constellation)
Elliptical galaxies
Astronomical objects discovered in 1864
Discoveries by Albert Marth
Hickson Compact Groups
150
2MASS objects
SDSS objects
071076
+01-59-047 | NGC 7609 | [
"Astronomy"
] | 792 | [
"Pegasus (constellation)",
"Constellations"
] |
76,875,697 | https://en.wikipedia.org/wiki/Trish%20Kerin | Trish Kerin is an Australian safety expert, engineer, director of the Institution of Chemical Engineers (IChemE), science communicator, and one of the Science Technology Australia, Superstars of STEM 2023-2024 cohort.
Education
Kerin graduated with honours in mechanical engineering at RMIT in 1994. Following graduation, Kerin worked for several years in project management, operational and safety roles for the gas, chemical and oil industries.
Career
Kerin has been a board member of the Australian National Offshore Petroleum Safety and Environmental Management Authority. She is a Chartered Engineer, registered Professional Process Safety Engineer, as well as a Fellow of IChemE, Engineers Australia and a senior member of the American Institute of Chemical Engineers. Kerin also holds a diploma in OHS, as well as a Master of Leadership and is a Graduate of the Australian Institute of Company Directors.
Kerin is the director of the IChemE Safety Centre, and leads a team that helps organisations share and learn about process safety. Kerin uses her engineering experience and leadership to help organisations improve process safety outcomes.
Kerin's work involves safety and risk minimisation in the workplace. She commented, in The Chemical Engineer publication,“People have a right to stay safe, no matter where they are. As chemical engineers address our global challenges and pivot our technologies to deliver a low-carbon future, all those engaged in process safety will be a crucial component in minimising the risk of operating in new fields.”
Publications
Kerin is the author of two books, "The Platypus Philosophy", on how to identify and manage weak signals, in safety processing. The second book is "Lets talk about your leadership", learning through the art of storytelling.
Select peer-reviewed publications include:
Kerin, T. (2016) The evolution of process safety standards and legislation following landmark events—what have we learnt? Process Safety Progress 35 (2), 165–170–17.
Kerin, T. (2018) Accounting for hindsight bias: improving learning through interactive case studies. Loss Prevention Bulletin. 264: 17.
Kerin, T. (2020) Taming the wild river rapids: How process safety can apply outside the process industries. Process safety progress 39 (1), e12088.
Media
Kerin was interviewed for Occham's Razor, on the ABC, about chemical safety and improving safety processes, with Tegan Taylor. They discussed how "everyone has a right to be safe at work", and Kerin shared a creative way to encourage spotting warning signs early, saving mistakes ahead of time.
Kerin also hosts a podcast with Endeavour Business Media's Chemical Processing Magazine called "Process Safety with Trish and Traci", as well as regular column called "Stay Safe".
Awards
2023-2024 – Science Technology Australia, Superstars of STEM.
2022 – ASBPE Bronze Award.
2022 – Leader of the Year award from Women in Safety in 2022.
2018 – Mary Kay O'Connor Process Safety Centre Trevor Kletz Merit award.
References
External links
Meet the 60 women named Superstars of STEM in 2022 – Women's Agenda article
Living people
Chemical engineers
RMIT University alumni
Year of birth missing (living people) | Trish Kerin | [
"Chemistry",
"Engineering"
] | 667 | [
"Chemical engineering",
"Chemical engineers"
] |
70,912,237 | https://en.wikipedia.org/wiki/Mahmoud%20Hashem%20Abdel-Kader | Mahmoud Hashem Abdel-Kader is a physical chemist and Professor of Photochemistry at Cairo University/NILES Institute. He founded the European Universities in Egypt
Education
Mahmoud Abdel-Kader received his BSc in Chemistry from Alexandria University in 1969, and was then associated with the Faculty of Science (chemistry) at Tanta University (initially a branch of Alexandria University, from 1972 on an independent university), where he performed "Spectroscopic Studies on Some Hydroxybenzanilides" and served as a teaching and research assistant (1970–1973). He was granted a DAAD scholarship in 1974 to perform doctoral studies in Germany and received his Ph.D. (Dr. rer. nat.) in "Spectroscopy and Photochemistry" from Stuttgart University in Germany in 1979. His doctoral studies were supervised by two German physicochemists, Theodor Förster († 1974) and his former scholar Horst E.A. Kramer. It included physicochemical investigations on the isomerization of a merocyanine (polymethine dye) of the stilbazolium betaine type and its corresponding acid
Career
After a 3-years period as lecturer in physical chemistry at Tanta University (1979–1982) and a post-doctoral research period at the University of Karlsruhe, now the Karlsruhe Institute of Technology (Department of Physical Chemistry, 1982 to 1983), he was appointed as Visiting Senior Researcher at the École Polytechnique Fédérale de Lausanne (Switzerland) from 1983 to 1984. He joined the Arabian Gulf University in Bahrain (Professor of Physical Chemistry/Photochemistry at the Faculty of Applied Sciences, 1985–1992), then the United Arab Emirates University (Professor of Physical Chemistry/Photochemistry at the Faculty of Science, 1992–1995). Mahmoud Abdel-Kader served as Visiting Professor at the Georgia Institute of Technology in Atlanta (USA) and at the Institute for Laser Technology in Medicine and Metrology of Ulm University (Germany).
He joined Cairo University in 1992 and acted as Department Chairman and Vice Dean of the National Institute of Laser-Enhanced Sciences (NILES) until August 2002. He had been involved in the establishment of the German University in Cairo (GUC), where he served as first University President (until 2017).
Research interests
Mahmoud Abdel-Kader's research interests are in:
Laser spectroscopy to study the kinetics and mechanism of ultrafast chemical reaction (photochemical isomerization, protolytic reactions and electron transfer processes),
Utilization of solar energy in photochemical conversions for malaria, filariasis and dengue fever vector control, for parasites such as schistosomiasis and agricultural pests using environmentally friendly (natural extract) photosensitizers, and
Application of nanoparticles in photodynamic diagnosis and therapy of cancer.
Projects, mentorship, published work and communications
Mahmoud Abdel-Kader is regarded as one of the experts in the field of modern photodynamic therapy (PDT) and the 2014-volume "Photodynamic Therapy: from Theory to Application", which he edited and to which he contributed as author, a summary in the various fields of PDT.
He has supervised approximately 90 master's theses and doctoral dissertations, and has published over 100 scientific communications in peer-reviewed journals and in conference proceedings. He is an inventor of 8 patents and has given more than 80 invited talks and plenary lectures at both national and international meetings.
Honors and awards
Internationally, Mahmoud Abdel-Kader is mainly known in the photochemistry-related research field. He was elected Officer of the European Society for Photobiology in 1997, then served as "Chair outside Europe" until 2001. In September 2024 he was awarded an Honorary Doctorate of Science by The University of East London for his contributions to chemistry.
In Egypt, Mahmoud Abdel-Kader has received various honors and awards:
(1995) National Incentive Award in Chemical Science
(1996) Distinguished State Prize in Chemistry
(1998) Egyptian State Medal in Chemistry
(2012) Excellence Award of Science from Cairo University
(2015) State Award Discretion in Advanced Technological Sciences
(2015) Member of the Egyptian Scientific Institute
(2017) First-Class Medal of the President of the Arab Republic of Egypt in Science and Arts
(2023) The Nile Award in Advanced Technological Sciences
References
External links
Living people
Physical chemists
Egyptian academics
University of Stuttgart alumni
Academic staff of Cairo University
Alexandria University alumni
Tanta University alumni
Year of birth missing (living people) | Mahmoud Hashem Abdel-Kader | [
"Chemistry"
] | 918 | [
"Physical chemists"
] |
70,912,899 | https://en.wikipedia.org/wiki/Sheth%E2%80%93Tormen%20approximation | The Sheth–Tormen approximation is a halo mass function.
Background
The Sheth–Tormen approximation extends the Press–Schechter formalism by assuming that halos are not necessarily spherical, but merely elliptical. The distribution of the density fluctuation is as follows: , where , , and . The parameters were empirically obtained from the five-year release of WMAP.
Discrepancies with simulations
In 2010, the Bolshoi cosmological simulation predicted that the Sheth–Tormen approximation is inaccurate for the most distant objects. Specifically, the Sheth–Tormen approximation overpredicts the abundance of haloes by a factor of for objects with a redshift , but is accurate at low redshifts.
References
Dark matter
Equations of astronomy
Astrophysics | Sheth–Tormen approximation | [
"Physics",
"Astronomy"
] | 165 | [
"Dark matter",
"Unsolved problems in astronomy",
"Astronomical sub-disciplines",
"Concepts in astronomy",
"Equations of astronomy",
"Unsolved problems in physics",
"Astrophysics",
"Exotic matter",
"Physics beyond the Standard Model",
"Matter"
] |
70,913,841 | https://en.wikipedia.org/wiki/Account%20pre-hijacking | Account pre-hijacking attacks are a class of security exploit related to online services. They involve anticipating a user signing up for an online service and signing up to the service in their name, and then taking over their account when they attempt to register it themselves. The attack relies on confusion between accounts created by federated identity services and accounts created using e-mail addresses and passwords, and the failure of services to resolve this confusion correctly.
Pre-hijacking was first identified as a class of vulnerabilities in 2022, based on research funded by Microsoft's Security Response Center.
Out of 75 online services surveyed, 35 were found to be vulnerable to various forms of the exploit. Vulnerable services included Dropbox, Instagram, LinkedIn, WordPress and Zoom. The existence of the vulnerability was reported to all the service providers before publication of the paper.
See also
Single sign-on
Federated identity
References
Computer security exploits
Hacking in the 2020s
Federated identity | Account pre-hijacking | [
"Technology"
] | 199 | [
"Computer security stubs",
"Computing stubs",
"Computer security exploits"
] |
70,914,136 | https://en.wikipedia.org/wiki/Penitanzacid%20F | Penitanzacid F was found as one of the twelve new tanzawaic acid derivatives, which were the secondary metabolites of the fungi Pencillum sp. KWF32 isolated from the tissues of Bathymodiolus sp. collected in the cold spring area of the South China Sea in 2021.
It may have anticoccidial, cytotoxic, lipid-lowering, superoxide anion production inhibiting, bacterial conjugation inhibiting, and NO production inhibiting properties as a tanzawaic acid derivative.
Structure and biosynthesis
The biosynthesis of Penitanzacid F starts from one acetyl-CoA, two methylmalonyl-CoA and three malonyl-CoA molecules with polyketide synthase (PKS). Then the product undergoes Diels-Alder Cyclization, chain elongation with two malonyl-CoA, and is oxidized to penitanzaicacid F.
References
Carboxylic acids
Ketones
Decalins
Tertiary alcohols
Dienes | Penitanzacid F | [
"Chemistry"
] | 222 | [
"Ketones",
"Carboxylic acids",
"Functional groups"
] |
70,915,488 | https://en.wikipedia.org/wiki/RZ%20Leonis%20Minoris | RZ Leonis Minoris is a cataclysmic variable star system in the northern constellation of Leo Minor. It undergoes frequent outbursts that vary in brightness from an apparent visual magnitude of 14.4 down to 16.8. Based on parallax measurements, this system is located at a distance of approximately 2,160 light years from the Sun.
This system became an object of interest in 1981 when V. A. Lipovetsky and J. A. Stepanian showed it to be a variable star with an ultraviolet excess. It shows strong variation from magnitude 14 down to 17, and the energy distribution at maximum resembles an OB star. The system displays a cyclical light curve, for which J. W. Robertson and colleagues in 1993 found a stable period of 19.2 days. The object differs from most dwarf novae by displaying short-term brightening and fading.
The behavior of the system is similar to ER Ursae Majoris, showing superoutbursts and superhumps. This indicates that RZ LMi is a SU Ursae Majoris-type dwarf novae belonging to the ER UMa sub-class. None of the variation can be linked to the orbital period of this binary system, and thus there is little known about the individual components. The high activity level of this object and the stability of the 19-day supercycle may indicate there is a third body in the system.
References
Further reading
Dwarf novae
White dwarfs
Leo Minor
Leonis Minoris, RZ | RZ Leonis Minoris | [
"Astronomy"
] | 309 | [
"Leo Minor",
"Constellations"
] |
70,915,950 | https://en.wikipedia.org/wiki/2021%20LL37 | is a large trans-Neptunian object in the scattered disc, around in diameter. It was discovered on 12 June 2021, by American astronomers Scott Sheppard and Chad Trujillo using Cerro Tololo Inter-American Observatory's Dark Energy Camera in Chile, and announced on 31 May 2022. It was 73.9 astronomical units from the Sun when it was discovered, making it one of the most distant known Solar System objects from the Sun . It has been identified in precovery images from as far back as 28 April 2014.
References
External links
Minor planet object articles (unnumbered)
20210612 | 2021 LL37 | [
"Physics",
"Astronomy"
] | 128 | [
"Concepts in astronomy",
"Unsolved problems in astronomy",
"Possible dwarf planets"
] |
70,916,007 | https://en.wikipedia.org/wiki/Karen%20Bakker | Karen Bakker (6 December 1971 – 14 August 2023) was a Canadian author, researcher, and entrepreneur known for her work on digital transformation, environmental governance, and sustainability. A Rhodes Scholar with a DPhil from Oxford, Bakker was a professor at the University of British Columbia. In 2022–2023 she was on sabbatical leave at Harvard, as a Harvard Radcliffe Institute Fellow. She was the recipient of numerous awards, including a Guggenheim Fellowship, Stanford University's Annenberg Fellowship in Communication, Canada's "Top 40 Under 40", and a Trudeau Foundation Fellowship.
Bakker's research focused on the intersection of digital technologies and environmental governance, digital environmental humanities, digital geographies, political ecology, and political economy. In the early part of her career, she focused on water and climate issues. Later, she concentrated on digital technology and environmental futures studies as critical yet pragmatic projects aiming to advance regenerative sustainability and environmental justice.
Career
Bakker was born in Montreal and raised in Ottawa. She trained in both the natural and social sciences at McMaster University (a combined Bachelor of Arts and Science (minor in Physics), followed by a DPhil in geography at the University of Oxford). She published over 100 academic publications, including seven sole-authored and edited scholarly books. Her work has been cited over 18,000 times.
She also served as a policy advisor to organizations at the forefront of digital innovation on environmental issues, including the Digital Research Alliance of Canada, Future Earth, Sustainability in a Digital Age, and the International Institute for Sustainable Development. Her advisory roles have also included the IPCC, National Round Table on Environment and Economy, OECD, UNDP, UNEP, UNESCO, and OHCHR.
Bakker was a member of the Decolonizing Water research collective and the Riverhood project team (funded by the EU), as well as the Coalition on Digital Environmental Sustainability, and the Policy Network on Environment of the Internet Governance Forum. She was also a board member of the National Research Council Canada, and a member of the editorial board of Global Environmental Change.
Bakker delivered over 200 conference presentations and invited lectures over the course of her career, at academic institutions such as Berkeley, Harvard, Stanford, and UCLA. These span several disciplines including geography and environmental studies, computer science, urban studies, labour studies, political ecology, and political economy.
Digital transformation and sustainability: The Smart Earth Project
Bakker's Smart Earth project engaged with two of the most destabilizing, controversial trends of our time: digital transformation and global environmental change.
Smart Earth brings together researchers, educators, and policymakers to study environmental knowledge and seeks to better understand the complex relationships between humans and nature. This project was launched with a meta-review of a smart technologies database in 2018. Bakker curated a website with learning tools regarding digital technologies and their application to environmental issues, and has collaborated with the United Nations Environment Program to map out a roadmap for international action on digital transformation and sustainability.
Interspecies communication and bioacoustics: The Sounds of Life
Bakker worked at the intersection of data and sustainability, exploring how technology can be leveraged to better protect, understand, cohabitate, and perhaps even communicate with our non-human counterparts. Bakker wrote critically about the potential pitfalls of the digital listening agenda, comparing it to an environmental variant of surveillance capitalism.
In October 2022, Bakker published her book: The Sounds of Life: How Digital Technology is Bringing Us Closer to the Worlds of Animals and Plants (Princeton University Press). The book was chosen as the NPR Science Friday Book Club book of the month for November 2022, selected as one of Malcolm Gladwell's Next Big Idea Club nominees in October 2022, and received both popular and critical acclaim, including a review in Science, which described the book as "thoughtful and rigorous…meticulously researched and colorfully presented…in a way that is accessible to non-experts. A wonderful mix of animal ecology, narratives of science-doing, futurism, and accounts of Indigenous knowledge that is as interdisciplinary as the field itself." She was invited to present the book at Google Talks, Aspen Ideas Festival and was the opening keynote at the TED 2023 conference.
Water governance
Bakker also worked broadly on issues of water accessibility, governance, and policy. Her publications include Privatizing Water: Governance Failure and the World's Urban Water Crisis (Cornell University Press), An Uncooperative Commodity: Privatizing Water in England and Wales (Oxford University Press), "Neoliberalizing Nature? Market Environmentalism in Water Supply in England and Wales" (2005), and "Water security: Debating an emerging paradigm" (2012). The Privatizing Water book was awarded the Urban Affairs Association Book Award (2011; honourable mention) and the Rik Davidson/Studies in Political Economy Book Prize (2012).
As Karen Le Billon
Writing under her nom de plume, Karen Le Billon, Bakker wrote two popular science books on children, food, and families. French Kids Eat Everything (HarperCollins, 2012) was published in 15 countries and 12 languages, awarded the Taste Canada Food Writing Award in 2013, and widely featured in the press, including The New York Times, The Guardian, and The Sunday Times. The follow up book Getting To Yum: The 7 Secrets Of Raising Eager Eaters (HarperCollins, 2014) was also well received by experts and the public.
Death
Bakker died after a brief illness on 14 August 2023.
Notable works
Books
Gaia's Web: How Digital Environmentalism Can Combat Climate Change, Restore Biodiversity, Cultivate Empathy, and Regenerate the Earth (Penguin Random House Canada, 2024)
The Sounds of Life:: How Digital Technology is Bringing Us Closer to the Worlds of Animals and Plants (Princeton University Press, 2022) .
Water Teachings, K. Bakker and C. Crane (eds) (2020)
Privatizing Water: Governance Failure and the World's Urban Water Crisis (Cornell University Press, 2010) .
Eau Canada: The future of Canada's water (UBC Press, 2007) .
An Uncooperative Commodity: Privatizing Water in England and Wales (Oxford University Press, 2004) .
Chapters and Articles (Peer-Reviewed)
References
External links
Water Governance Project
Decolonizing water curriculum
Official UBC Profile
UBC Dr. Karen Bakker Memorial Fund
1971 births
2023 deaths
Sustainability scientists
21st-century Canadian women writers
Academic staff of the University of British Columbia
Canadian women academics
McMaster University alumni
Canadian Rhodes Scholars
Canadian geographers
Women geographers
Scientists from Montreal | Karen Bakker | [
"Environmental_science"
] | 1,368 | [
"Sustainability scientists",
"Environmental scientists"
] |
70,916,199 | https://en.wikipedia.org/wiki/Geostationary%20Extended%20Observations | The Geostationary Extended Observations (GeoXO) satellite system is the National Oceanic and Atmospheric Administration (NOAA)'s planned replacement for the existing Geostationary Operational Environmental Satellite (GOES) satellites. These new geostationary satellites will make weather, ocean, and climate observations. The project aims to begin observations in the early 2030s as the GOES-R satellites reach their operational lifetime. The first GeoXO satellite is scheduled to be launched in 2032, with two more following in 2035, and the mission will maintain and advance NOAA’s geostationary observations through 2055.
NASA is developing the satellites and awarded multiple "Phase A" contracts in 2021 and 2022, including ones with Lockheed Martin and Maxar to study using their LM-2100 and 1300-class satellite busses, respectively. The program was officially approved by the United States Department of Commerce in December 2022, moving the program from the study phase to the development phase, and in March 2023 NASA and NOAA awarded L3Harris a $765.5 million contract to develop the first two GeoXO Imager (GXI) instruments. On September 11, 2023, NASA and NOAA awarded Ball Aerospace (later sold to BAE Systems Inc.) a $486.9 million contract to develop the GeoXO Sounder (GXS) instrument.
Unlike the payloads carried on GOES-12 through GOES-19, GeoXO satellites will not carry any instruments for observing space weather. Continuity of space weather and environment observations after the retirement of the GOES system is planned to be provided through the Space Weather Follow On-Lagrange 1 (SWFO-L1) mission and the Space Weather Next program.
References
External links
NOAA's GeoXO page
Proposed satellites
2030s in spaceflight
Weather satellites of the United States | Geostationary Extended Observations | [
"Astronomy"
] | 380 | [
"Astronomy stubs",
"Spacecraft stubs"
] |
70,917,175 | https://en.wikipedia.org/wiki/10%20Delphini | 10 Delphini (10 Del) is a solitary star in the equatorial constellation Delphinus. It has an apparent magnitude of 6.00, allowing it to be faintly seen with the naked eye. Parallax measurements put the object at a distance of 493 light years but is drifting closer with a heliocentric radial velocity of .
10 Delphini has a stellar classification of K4 III or K2 III, both indicating that it is a red giant. However, there is some uncertainty behind the first classification. It has twice the mass of the Sun but at an age of 794 million years — expanded to 18 times the radius of the Sun. It shines at from its enlarged photosphere at an effective temperature of 4,378 K, giving it an orange glow. 10 Del has a solar metallicity.
10 Del has been suspected to be a variable star, although it hasn't been catalogued as such in the GCVS.
References
Delphinus
K-type giants
197121
102080
7918
+14 4393
Delphini, 10 | 10 Delphini | [
"Astronomy"
] | 223 | [
"Delphinus",
"Constellations"
] |
70,917,667 | https://en.wikipedia.org/wiki/Exceptional%20point | In quantum physics, exceptional points are singularities in the parameter space where two or more eigenstates (eigenvalues and eigenvectors) coalesce. These points appear in dissipative systems, which make the Hamiltonian describing the system non-Hermitian.
Photonics
The losses in photonic systems, are a feature used to study non-Hermitian physics. Adding non-Hermiticity (such as dichroism) to photonic systems which present Dirac points transforms these degeneracy points into pairs of exceptional points. This has been demonstrated experimentally in numerous photonic systems such as microcavities and photonic crystals. The first demonstration of exceptional points was made by Woldemar Voigt in 1902 for optical modes in crystals.
Fidelity and fidelity susceptibility
In condensed matter and many-body physics, fidelity is often used to detect quantum phase transitions in parameter space. The definition of fidelity is the inner product of the ground state wave functions of two adjacent points in parameter space, , where is a small quantity. After series expansion, , the first-order correction term of fidelity is zero, and the coefficient of the second-order correction term is called the fidelity susceptibility. The fidelity susceptibility diverges toward positive infinity as the parameters approach the quantum phase transition point.
For the exceptional points of non-Hermitian quantum systems, after appropriately generalizing the definition of fidelity,
the real part of the fidelity susceptibility diverges toward negative infinity when the parameters approach the exceptional points.
For non-Hermitian quantum systems with PT symmetry, fidelity can be used to analyze whether exceptional points are of higher-order. Many numerical methods such as the Lanczos algorithm, Density Matrix Renormalization Group (DMRG), and other tensor network algorithms are relatively easy to calculate only for the ground state, but have many difficulties in computing the excited states. Because fidelity only requires the ground state calculations, this approach allows most numerical methods to analyze non-Hermitian systems without excited states, and find the exceptional point, as well as to determine whether it is a higher-order exceptional point.
See also
Dirac cones
Non-Hermitian quantum mechanics
References
Quantum mechanics
Photonics | Exceptional point | [
"Physics"
] | 459 | [
"Theoretical physics",
"Quantum mechanics"
] |
70,917,854 | https://en.wikipedia.org/wiki/Couty%27s%20azetidine%20synthesis | Couty's azetidine synthesis is one of the most efficient synthesis of azetidines named after French organic chemist François Couty from University of Versailles Saint-Quentin-en-Yvelines. It enables an easy synthesis of a broad range of enantiopure azetidines from readily available β-amino alcohols by their chlorination followed by deprotonation and a 4-exo-trig ring closure.
It was originally reported from N-alkyl- or N-aryl- N-cyanomethylated β-aminoalcohols but other electron-withdrawing groups such as esters or phosphonates are also suitable and the chloride can be replaced by a Michael acceptor. Over the years, the Couty's azetidine synthesis was shown to be efficient to access a variety of enantiopure azetidines and 2-cyano-azetidines were shown to be excellent scaffolds and building blocks in heterocyclic chemistry and for molecular diversity. It was notably extensively utilized by the Broad Institute of MIT and Harvard for the synthesis and profiling of a collection of azetidine-based scaffolds for the development of CNS-focused lead-like libraries, and by Galapagos NV for the discovery and optimization of an azetidine library for the development of free fatty acid receptor 2 (FFA2) antagonists.
References
Chemical synthesis
Heterocycle forming reactions | Couty's azetidine synthesis | [
"Chemistry"
] | 312 | [
"Chemical synthesis",
"nan",
"Heterocycle forming reactions",
"Organic reactions"
] |
70,917,932 | https://en.wikipedia.org/wiki/Phoma%20candelariellae | Phoma candelariellae is a species of lichenicolous (lichen-eating) fungus in the family Didymellaceae. It is found in the Central Anatolia Region of Turkey and in Ukraine, where it grows parasitically on the apothecia (fruiting structures) of the saxicolous (rock-dwelling) lichen Candelariella aurella.
Taxonomy
The fungus was formally described as a new species in 2016 by Zekiye Kocakaya and Mehmet Gökhan Halıcı. The type specimen was collected northwest of Sivrihisar (Eskişehir) at an altitude of , where it was found growing on the apothecia of the saxicolous lichen Candelariella aurella, which itself was growing on calcareous rocks.
Phoma candelariellae is the only member of Phoma that grows on lichen genus Candelariella. David Hawksworth and colleagues later expressed doubt about the placement of the taxon in genus Phoma, suggesting that a transfer may be necessary, "as the species does not appear to be congeneric with the type species of the genus".
Description
The conidiomata of Phoma candelariellae are in the form of pycnidia—spherical to pear-shaped reproductive structures, that begin more or less immersed in the host tissue, but later burst partially through the surface. These black spots are covered by a clear gelatinous sheath; their dimensions are typically in the range 98.5−117 by 74−103 μm. A 12 μm-diameter ostiole provides an opening for the release of abundant conidia, which themselves are more or less spherical with a smooth wall and a gelatinous sheath, contain a single internal oil droplet, and measure about 5 μm across.
Habitat and distribution
The only known host of Phoma candelariellae is Candelariella aurella. Infection by the fungus is pathogenic, causing discolouration (blackening) of the host tissue, and diminishing and ultimately destroying the hymenium of the infected apothecia.
At the time of its original publication, Phoma candelariellae had been documented from only two localities in the Central Anatolia Region of Turkey. The authors suggested that the fungus likely has a wider distribution, as the host is widely distributed in the Northern Hemisphere. This was confirmed when it was reported from the Zhytomyr, Kherson, and Mykolaiv regions of Ukraine.
References
candelariellae
Fungi described in 2016
Lichenicolous fungi
Fungi of Europe
Fungus species | Phoma candelariellae | [
"Biology"
] | 544 | [
"Fungi",
"Fungus species"
] |
70,918,415 | https://en.wikipedia.org/wiki/Sergey%20Kondratyuk | Sergey Yakovlevich Kondratyuk () (born 17 May 1959) is a Ukrainian botanist specialising in lichenology. His research deals with the taxonomy, floristics, ecology and geography of lichens and lichenicolous fungi. He has worked at the for more than 40 years. In 2014 Kondratyuk was awarded the State Prize of Ukraine in Science and Technology.
Early life and education
Kondratyuk was born in the Kirovohrad region, in Ulyanovsk. After graduating from school in 1976 he became a student of the Faculty of Biology at Kyiv State University. He specialized in the Department of Lower Plants. While still a student, Kondratyuk started to study lichens under the guidance of O.B. Bloom. Then began his career at the Institute of Botany (1979), as a senior technician and later an engineer in the Department of Algology and Lichenology. He continued his career as a graduate student of the institute (1981–1984). After successfully defending his dissertation entitled "Lichens of the Dnieper Upland" (1985), Kondratyuk continued to work at the institute, having passed the path from junior to leading researcher, head of the laboratory and department, scientific secretary, deputy director and finally acting director of the institute. In 1996 Kondratyuk defended his doctoral dissertation "Lichen flora of the plains of Ukraine and its analysis"; in 2006 he received the title of Professor.
Research
Since 1995, Kondratyuk has been working for many years with Professor Ingvar Kärnefelt from the Botanical Museum of Lund University (Sweden) to study lichens of the family Teloschistaceae. Many new genera have been circumscribed as a result, including Xanthomendoza, Josefpoeltia, Oxneria, and Rusavskia. Extensive collaborations with South Korean scientists have also resulted in the description of many taxa previously unknown to science. As of 2019, Kondratyuk has been the author or co-author of more than 400 scientific publications. Some well-known publications include "Flora of lichens of Ukraine. Volume 2. Issue 2." (1993), "The second Checklist of Lichen forming, Lichenicolous and Allied fungi of Ukraine" (1998), "A Catalog of the Eastern Carpathian Lichens" (2003), "Checklist of Lichens of the Western Carpathians" (2004), " Determinant of lichens of Russia. Issue 9" (2004), "Lichen-Forming, Lichenicolous and Allied Fungi of Israel"(2005), "Lichenoindication (Manual)" (2006), "Indication of the state of the environment of Ukraine with the help of lichens" (2008).
The fungus Epibryon kondratyukii , discovered in southern Ukraine, was named in his honour in 2019.
See also
:Category:Taxa named by Sergey Kondratyuk
References
1959 births
Lichenologists
20th-century Ukrainian scientists
21st-century Ukrainian scientists
Ukrainian botanists
Taxonomists
Laureates of the State Prize of Ukraine in Science and Technology
Taras Shevchenko National University of Kyiv alumni
Living people | Sergey Kondratyuk | [
"Biology"
] | 669 | [
"Taxonomists",
"Taxonomy (biology)"
] |
70,919,390 | https://en.wikipedia.org/wiki/Guzhuang%20%28costume%29 | (), also called ancient-style dress, refers to a style of Chinese costume attire which are styled or inspired by ancient Chinese clothing (typically or ). is typically used as stage clothes in Chinese opera and in Chinese television drama, such as in period drama which are normally set in imperial China prior to 1911, and in the and genre. While the style of is based on ancient Chinese clothing, show historical inaccuracies.
Chinese opera
In Chinese opera, plays depicting is called (), also known as (), or (), were performed by Mei Lanfang. is an important concept in both the field of Chinese opera and to early Chinese film.Mei Lanfang is also credited for having invented () which include the set of that he created along with ().
This form of emerged in 1915 when new Chinese opera costumes had to be created for a new category of female role which had also been developed by Mei Lanfang. Therefore, Mei Lanfang designed new female costumes by referring to ancient Chinese sculpturesand to ancient Chinese paintings, especially women in classical Chinese scroll paintings, often based on from mythological figures. His goal was to make his costumes more elegant instead of making it look ancient.His costume designs then became known as due to their relationship with ancient China, in particular the pre-Qing dynasty period from which his costumes designs were based.
The designed by Mei Lanfang is characterized with fitted waist. The developed by Mei Lanfang different from the traditional Chinese opera costumes in some aspects: the skirts were longer; the skirt was worn under the jacket to make the character look slimmer; the water sleeves were longer and wider; and the accessories were less gaudy. Other performers such as Ouyang Yuqian and Feng Zihe also contributed to the development of the design.
Chinese television and entertainment media
are typically used in Chinese television drama and movies. They are often depicted in the , , and genre. is also depicted in animations, including and Chinese-theme animations produced outside of China.
Relationship with film and drama genre
The first film produced in China was Dingjun Mountain in 1905 which depicted extracted scenes from a Beijing opera play performed by Tan Xinpei. The film was based on the 70th and 71st chapters of the Romance of the Three Kingdoms. In terms of genre, it can be classified as (), a historical costume film, or . The 1920s was marked by the adaptation of traditional Chinese indigenous genre into cinema. These genres were adapted from Chinese literature and from the Chinese opera stage play as a countermovement against the prevalence of European and American film products. The Tianyi Film Company was a major studio which specialized in Chinese genres at that time; its succeeding company, the Shaw Brothers Studio in Hong Kong continued to produce indigenous Chinese genres, such as Huangmei opera films and guzhuang epics.
and
(), also known as period costume film, is indigenous genre to China and first emerged in the 1920s in China. This genre is similar to costume drama, period film, and historical film. However, by definition the term (), which literally means "ancient", does not refer to films and dramas which are set in the Republic of China as the Republican period is a symbol of modernity and the end of tradition.
are therefore depicted in period drama (i.e. historical drama, which is also called drama) which are normally set in imperial China prior to 1911. also typically depict adaptations of traditional Chinese folktales, plays, and popular novels. As a distinct genre, it is characterized by its focus on ancient history and historical personalities.
Some of the early Chinese movies depicting were based on Chinese opera play and Chinese folklore, such as (1926) and White Snake (1926) released by Tianyi Film Company; Liang Shanbo and Zhu Yingtai produced in 1953 by the Shanghai Film Studio.
, , and
The tradition of is over two thousand years old having been passed through Chinese folklore, novels, historiography, and popular performing traditions (such as and Chinese opera). The origins of genre in cinema, however, is quite recent and emerged in the 20th century. In cinema, the genre can be traced back to the and genre as one of its derivatives.
The () genre, which often depicts -immortals and demons, was also developed in the 20th century and was also a derivatives of the .
The genre was initiated by the Tianyi Film Company in 1925. The early genre, however, was also not always ; and therefore, it did not always involve the wearing of . In the 21st century, the genre can be a guzhuangpian and a movie. The genre tends to dress its characters into .
The genre, which has grown in popularity in the 21st century, is a sub-genre of . The genre typically involves -immortals and immortality cultivation.
Characteristics and costume design
Most used in the production of television dramas, movies and animations do not conform to historical facts and/or are fantasy-inspired. Some are based on different existing historical clothing worn in different dynasties, and/or inspired by Chinese opera costumes, and murals (e.g. Dunhuang frescoes); they would sometimes have features, or have attire, added, removed, simplified, to create a desired visual impact or to meet the production needs. It is also possible for various ethnic Chinese elements to be mixed and matched when designing ; combining modern fashion elements and/or western-style clothing elements can also be done.
When designing for films and television dramas, costumes designers consider the modern aesthetic taste of its audience while also conforming and respecting the historical reality. The used in the genre, for example, is based on the historical hanfu, but is modernized in terms of design resulting in the guzhuang being different from its historical version.
Moreover, in most movies and television drama, the colours, style, and pattern of are also based on the characters found in the script; these costumes characteristics are used to better shape the character's image and to allow the audience better understand the character through his visual image and to allow for the distinction between characters. Characters wearing , for example, can have a colour theme which reflect his initial personality; however, this colour theme may change throughout the character development. It is also impossible for costume designers to fully restore garment and garment-related artefacts; and therefore, guzhuang designers need to innovate their costume designs based on historical facts.
List of movies, drama, and animations featuring guzhuang
Examples of movies and dramas which uses are: The cave of the Silken Web (1927), Luoyang bridge (1928), Dragon Inn (1967), a Chinese Ghost Story (1987), The Swordsman (1990), Swordsman II (1992) and The East Is Red (1993), Ashes of Time (1994), Hero (2002), House of Flying Daggers (2004), Curse of the golden flower (2006), The Empress of China (2014), The Journey of Flower (2015), The Princess Weiyoung (2016), Eternal Love (2017), Ruyi's Royal Love in the Palace (2018), The Untamed (2019), Mulan (2020 Film), and Word of Honour (2021), etc. Example of animations which depicts are: Mulan (1998 film), Kungfu panda.
Literature, web-novels, and comics
can be found in , such as () and . is a similar genre and a derivative of the shoujo manga; it originally followed similar visual aesthetics as the Japanese shoujo manga in its early development before starting to develop Chinese characteristics between the 2000s and early 2010, after 2010s, became distinct from the Japanese shoujo manga both in terms of visual aesthetics and storyline. In the mid-2010s, and (i.e. stories adapted from Chinese history and legendary tales, and fictional love stories set in imperial China) became popular. Examples of depicted in manhua can be found in Chang an Fantastic Night () by Han Lu, () by Xia Da (released in 2008), by Xia Da, () by Feng Nong, etc. can also be found in , such as Bride of the Water God by Yun Mi-kyung, and in the Chinese-theme Japanese manga, such as by Yura Kairi.
Influences and derivatives
Wei-Jin Style Hanfu
is often confused with or misinterpreted as by most people who are not familiar with . And, some enthusiasts also wear it instead of wearing . is, however, also a factor of influence (among many others) to the design of modern ; for example, the design of style () is a relatively modern design which was influenced by Chinese movies and television drama series and does not exist in history. found in television drama have also left a deep impact on Chinese audience. Many fans also wear in their everyday lives, which then promote the growing industry.
Another -style costume which has influenced modern clothing in modern-day China is the designed by costume designer Ye Jintian in 2001 for the role of drama female character Xiu He, played by Chinese actress Zhou Xun, in the Chinese television drama (), a drama set in the Republican era of China. Although the drama was set in the Republic of China, the costume was mainly inspired by the of the Qing dynasty, especially those used in the late years of the Qing dynasty in the 1910s as part of the bridal attire. While basing himself on the clothing of the Qing dynasty, Ye Jintian, however, did not fully respected the historical accuracy of the dress and instead mixed several elements together from similar eras in his costume design. As the gives a feeling of dignity and beauty to its wearer, the designed by Ye Jintian became progressively popular and eventually became a form of traditional Chinese-style wedding dress chosen by many Chinese brides during their marriage nowadays.
See also
Hanfu
Hanfu movement
Qizhuang
Chinese opera
List of Chinese television series
Notes
References
External links
The Cave of the Silken Web (1927)
Performing arts
Costume design | Guzhuang (costume) | [
"Engineering"
] | 2,055 | [
"Costume design",
"Design"
] |
70,919,849 | https://en.wikipedia.org/wiki/NGC%204502 | NGC 4502 is a spiral galaxy located in the constellation Coma Berenices, originally discovered by William Herschel on March 21, 1784. The galaxy features a broad HI line. In the background and to the celestial north of the galaxy, two uncatalogued, distant colliding galaxies can be seen.
See also
New General Catalogue
References
4502
Astronomical objects discovered in 1784
Discoveries by William Herschel
Unbarred spiral galaxies
Coma Berenices | NGC 4502 | [
"Astronomy"
] | 93 | [
"Coma Berenices",
"Constellations"
] |
70,920,019 | https://en.wikipedia.org/wiki/Easystats | The easystats collection of open source R packages was created in 2019 and primarily includes tools dedicated to the post-processing of statistical models. As of May 2022, the 10 packages composing the easystats ecosystem have been downloaded more than 8 million times, and have been used in more than 1000 scientific publications. The ecosystem is the topic of several statistical courses, video tutorials and books.
The aim of easystats is to provide a unifying and consistent framework to understand and report statistical results. It is also compatible with other collections of packages, such as the tidyverse. Notable design characteristics include its API, with a particular attention given to the names of functions and arguments (e.g., avoiding acronyms and abbreviations), and its low number of dependencies.
History
In 2019, Dominique Makowski contacted software developer Daniel Lüdecke with the idea to collaborate around a collection of R packages aiming at facilitating data science for users without a statistical or computer science background. The first package of easystats, insight was created in 2019, and was envisioned as the foundation of the ecosystem. The second package that emerged, bayestestR, benefitted from the joining of Bayesian expert Mattan S. Ben-Shachar. Other maintainers include Indrajeet Patil, Brenton M. Wiernik, Etienne Bacher, and Rémi Thériault.
The easystats collection of packages as a whole received the 2023 Award from the Society for the Improvement of Psychological Science (SIPS).
Packages
The easystats ecosystem contains ten semi-independent packages.
insight: This package serves as the foundation of the ecosystem as it allows manipulating objects from different R packages.
datawizard: This package implements some core data manipulation features.
bayestestR: This package provides utilities to work with Bayesian statistics. The package received a Commendation award by the Society for the Improvement of Psychological Science (SIPS) in 2020.
correlation: This package is dedicated to running correlation analyses.
performance: This package allows the extraction of metrics of model performance.
effectsize: This packages computes indices of effect size and standardized parameters.
parameters: This package centres around the analysis of the parameters of a statistical model.
modelbased: This package computes model-based predictions, group averages and contrasts.
see: This package interfaces with ggplot2 to create visual plots.
report: This package implements an automated reporting of statistical models.
See also
Tidyverse
R (programming language)
References
Data analysis software
Free R (programming language) software
Statistical software
2019 software | Easystats | [
"Mathematics"
] | 522 | [
"Statistical software",
"Mathematical software"
] |
70,920,557 | https://en.wikipedia.org/wiki/CIT%206 | CIT 6 is a carbon star in the constellation Leo Minor. It is a semiregular variable star, with a period of about 628 days, and has been given the variable star designation RW Leonis Minoris. It is perhaps the second most studied carbon star, after CW Leonis. CIT 6 was discovered in 1966 by a group at the California Institute of Technology (which is why it is named CIT 6) who found it using the same 62-inch infrared telescope on Mount Wilson that was used to produce the Two-Micron Sky Survey. It is the second brightest carbon star in the near-infrared, after CW Leonis (which is much closer to us).
CIT 6 is believed to be a highly evolved star, in transition from the AGB phase to the protoplanetary nebula phase. It is surrounded by a thick circumstellar envelope (CSE) of dust and molecular gas. Absorption and re-radiation of the starlight by the dust makes the object far brighter in the infrared than it is in visible light. The molecular gas was first seen by Knapp and Morris in 1985, who detected a CO emission line. Later studies of millimeter-wave radio emission have detected over 20 different molecular species in the CSE. There include CN, HCN, HC3N, HC5N, HC7N, SiS, SiO, SiC2, C4H and CH3CN.
HST images show that the dust component of the innermost region of CIT 6's CSE has developed the bipolar shape that is frequently seen in protoplanetary nebulae. High spatial resolution interferometric measurements show that the CO emission lines arise from a spiral structure. The spiral structure of the molecular gas outflow, combined with the bipolar shape seen by the HST, strongly suggests that CIT 6's AGB star has a binary companion.
Although it's invisible to the human eye, the CSE of CIT 6 covers a region of our night sky roughly 1/4 of the size of the full moon. The outermost edge of the CSE was seen by the GALEX satellite. It appears as two long arcs of emission (of ultraviolet light) 15 and 18 arc minutes in diameter, caused by the stellar wind colliding with the interstellar medium. The large size of the CSE indicates that CIT 6 has been losing mass at a high rate for at least 93,000 years.
See also
List of largest known stars
Notes
References
Semiregular variable stars
Leonis Minoris, RW
Leo Minor
Carbon stars
Binary stars | CIT 6 | [
"Astronomy"
] | 534 | [
"Leo Minor",
"Constellations"
] |
70,920,609 | https://en.wikipedia.org/wiki/Diplodia%20corticola | Diplodia corticolaa is a species of anamorphic fungus in the family Botryosphaeriaceae.
References
Botryosphaeriaceae
Fungi described in 2004
Fungus species | Diplodia corticola | [
"Biology"
] | 39 | [
"Fungus stubs",
"Fungi",
"Fungus species"
] |
70,920,887 | https://en.wikipedia.org/wiki/Orange%20petunia | Orange petunias or A1-DFR petunias are genetically modified organisms which contain a transgene from maize that colors the petunia flowers orange. First created in a 1987 experiment at the Max Planck Institute for Plant Breeding Research in Cologne, the petunias were subsequently released into the wild but were not commercialized. In 2015 orange petunias were discovered in Helsinki by botanist Teemu Teeri, leading to a regulatory response dubbed the petunia carnage of 2017 in which plant sellers were directed to destroy the modified petunia plants rather than sell them. The United States Department of Agriculture approved the sale of orange petunias in the United States in January 2021.
History
Orange petunias were created in 1987 by a team of researchers at the Max Planck Institute for Plant Breeding Research in Cologne, led by geneticist Peter Meyer. In a paper published in Nature the same year, the researchers demonstrated that the insertion of a gene from maize into a petunia would cause the plant to produce pelargonidin, turning its flowers salmon. This was the first modification of flower color using a transgene. The trial of the technology involved the planting of 30,000 such genetically modified petunias, which were the first transgenic plants to be allowed into the field in Germany. According to Meyer, public opinion was strongly against the planting at the time.
Despite the controversy over production of the petunias, a corporation affiliated with seed company Zaadunie acquired a license for the technology, and reported in 1995 that they had created commercially viable orange petunias. Compared to the original petunias, the gene for orange pigment was more consistently expressed in these plants, and the flowers were a vivid orange color. Rogers NK collaborated with Zaadunie to gain approval for a field trial of the petunias in Florida, but according to their originator Peter Meyer, the petunias were never commercialized by any of these companies. Orange petunias were also created through a similar genetic modification from other plant sources, including Gerbera, Calibrachoa, and rose; these were never officially commercialized either.
Petunia carnage of 2017
In 2015, plant biologist Teemu Teeri noticed orange petunias outside a train station in Helsinki. Teeri knew the history of the modified flowers, and initially believed the orange color of these flowers to be fake. After analyzing a sample he discovered that the DNA of the flowers matched the modification described in the original 1987 paper.
Teeri notified a regulator with the Finnish Board for Gene Technology of the petunias' presence, a decision which he later told ScienceInsider he regrets. On April 27, 2017, the Finnish Food Safety Authority called for the removal of eight petunia varieties from the market in response to the presence of unauthorized genetically modified petunias. The plants had been imported from Germany and the Netherlands. Because they were not authorized as genetically modified organisms by the European Union, they were required to be identified and destroyed; other European countries began related investigations. The Department for Environment, Food and Rural Affairs in the United Kingdom launched an investigation into their sale, and campaign group GM Freeze warned consumers to avoid the plants.
By May 2, 2017, the Animal and Plant Health Inspection Service (APHIS) of the United States Department of Agriculture (USDA) was performing screenings with plant breeders to search for cauliflower mosaic virus in petunias, as the virus is commonly used to control the expression of transgenes. As of May 24, 2017, APHIS screenings in response to the rediscovery of orange petunias had identified 10 varieties of genetically engineered petunia, along with 21 more that were "implicated as potentially GE". The agency released guidance directing breeders and sellers in the United States to autoclave, bury, compost, incinerate, or use a landfill to dispose of the identified petunia varieties. Michael Firko, director of the Biotechnology Regulatory Services division of APHIS, stated that certain companies may have unknowingly been selling genetically modified petunias for almost a decade; one of his team members had noticed the flowers in a centrepiece at a graduation party in May 2017 but did not take a sample because "she didn't want to destroy the nice floral display".
Regulatory agencies' sudden awareness of the presence of unauthorized genetically modified organisms on the market led to a recall campaign and the destruction of modified petunia plants, causing worldwide economic losses. Orange petunias were essentially removed from the global economic market, with a few exceptions including Canada. The event was dubbed the "petunia carnage of 2017" by photographer Klaus Pichler.
The events leading to the widespread presence of orange petunias are unclear. Tracing the development of the plants is difficult in part because of the complexity of the biotechnology field; Zaadunie was owned by conglomerate Sandoz when the orange petunias were first developed, but Sandoz merged into Novartis in 1996, and Novartis merged its agricultural arm with that of AstraZeneca in 2000 to form Syngenta. An executive at trade group AmericanHort suggested that "somewhere along the line [...] somebody lost sight of the fact that the original color breakthrough in question here had been achieved through genetic modification".
Subsequent regulation
The USDA stated in 2017 that it would not pursue action against companies which had distributed orange petunias, as it appeared that they had not been aware that the plants were unauthorized genetically modified organisms. In 2021, a petition by German plant supply company Westhoff led the USDA and APHIS to deregulate orange petunias in the United States, allowing their sale.
Traits
Genetic
Flower coloration from anthocyanins in the ornamental petunia, Petunia × hybrida, is an example of substrate specificity of one enzyme limiting the spectrum of possible products of the pathway. Anthocyanins are water-soluble pigments giving flowers, fruits and sometimes vegetative parts of plants colors ranging from orange and red to blue and purple. Anthocyanins are extensively glycosylated and acylated, which affects their visual properties. At the aglycone level the three most common variants of the molecule are the anthocyanidins pelargonidin, cyanidin and delphinidin, differing by the number of hydroxyl groups (one, two or three, respectively) in the B-ring of the molecule. Hydroxylation takes place at the level of dihydroflavonols in the pathway (possibly earlier in some cases, or later in others) by two enzymes, flavonoid 3'hydroxylase (F3'H) and flavonoid 3'5'hydroxylase (F3'5'H). The enzyme dihydroflavonol reductase (DFR) converts dihydroflavonols to corresponding leucoanthocyanidins, which then are oxidized to anthocyanidins by anthocyanidin synthase (syn. leucoanthocyanidin dioxygenase). In petunia, the DFR enzyme does not react with the simplest precursor (dihydrokaempferol); therefore, the natural range of petunia flower colors lacks orange hues typical to pelargonidin derivatives.
Orange petunias contain a gene encoding dihydroquercetin 4-reductase from maize, named A1 or A1-DFR. This transgenic complementary DNA enables production of orange pelargonidin pigment. One study of three commercially distributed orange petunia varieties found the A1 type 2 allele, which matches the modification made in the 1980s and thus suggests a direct relationship between modern orange petunias and the 1987 experiment. Another study noted the presence of the nptII gene, a common marker of selective gene transfer. While some of the initial orange petunia experiments used a DFR gene from plants other than maize, genetic evidence suggests maize as the original source of the DFR gene in present-day orange petunias.
While the original orange petunias had poor horticultural properties, plant breeders were able to introduce the genetic modification into hardier petunia varieties through crossbreeding.
Visual
While petunias and similar plants do not normally produce orange or bright red flowers because they are genetically unable to synthesize such pigments, genetically modified orange petunias have orange flowers. Flower size and shade vary across different varieties. Some petunia varieties that produce red or purple flowers also carry the gene modification that originally created orange petunias.
Interaction with other organisms
Orange petunias are not pests and are not considered noxious weeds in the United States, where they are not sexually compatible with any wild plants. The Finnish Food Safety Authority noted after their investigation that while the petunias were not authorized for cultivation in the European Union, they "do not cause any risk to people or the environment".
Varieties
Orange petunia varieties carry commercial names including 'African Sunset', 'Cascadias Indian Summer', and 'Bonnie Orange' as well as 'Salmon Ray', 'Viva Orange', and 'Electric Orange'.
References
Citations
Works cited
Source attribution
Petunia
Genetically modified organisms in agriculture
Regulation of genetically modified organisms
Flowers | Orange petunia | [
"Engineering",
"Biology"
] | 1,925 | [
"Regulation of genetically modified organisms",
"Genetic engineering",
"Regulation of biotechnologies"
] |
70,921,326 | https://en.wikipedia.org/wiki/Leaf-and-dart | Leaf-and-dart (also known as rais-de-cœur and heart-and-dart) is an ornamental motif made up of heart-shaped leaves (or waterleaves inside hearts) alternating with spearheads (or darts). This motif was used in Ancient Greek and Roman architecture. It was taken up again during the Renaissance, abundantly in the 18th century, being used in the Louis XVI style.
The French word literally means "rays (beams of light) from heart[s]" (its Italian equivalent being ), as the "darts" can resemble triangular lightrays emerging from between the hearts.
The singular equivalent () is rarely used.
Gallery
See also
Egg-and-dart, a similar motif
Notes
External links
Ornaments (architecture)
Visual motifs | Leaf-and-dart | [
"Mathematics"
] | 161 | [
"Symbols",
"Visual motifs"
] |
70,922,122 | https://en.wikipedia.org/wiki/GIS%20Arta | GIS Arta or GIS Art for Artillery is military software used to coordinate artillery strikes. It has been used in the 2022 Russian invasion of Ukraine by the Armed Forces of Ukraine. It has fast targeting (one minute), it does not require reconnaissance units to use specialized devices (they use smartphones), and it does not require artillery pieces to be clustered together. It has been compared to the German artillery software ESG Adler. It was developed by Ukrainian programmers, with involvement by British digital map companies.
See also
Delta (situational awareness system)
References
External links
GIS Arta, Official website
Location-based software
Military equipment of the Russian invasion of Ukraine | GIS Arta | [
"Technology"
] | 137 | [
"Computing stubs",
"Software stubs"
] |
70,922,460 | https://en.wikipedia.org/wiki/Electrochemical%20Energy%20Reviews | Electrochemical Energy Reviews is a peer-reviewed scientific journal by Springer Nature. It is published on a quarterly basis. It was established in 2018 and is currently edited by Jiujun Zhang and Xueliang Andy Sun.
Abstracting and indexing
The journal is abstracted and indexed in:
Compendex
DOAJ
Science Citation Index Expanded
Scopus
According to the Journal Citation Reports, the journal has a 2020 impact factor of 28.905.
References
External links
English-language journals
Quarterly journals
Hybrid open access journals
Academic journals established in 2018
Electrochemistry journals
Springer Science+Business Media academic journals | Electrochemical Energy Reviews | [
"Chemistry"
] | 121 | [
"Electrochemistry journals",
"Electrochemistry",
"Electrochemistry stubs",
"Physical chemistry journals",
"Physical chemistry stubs"
] |
70,922,711 | https://en.wikipedia.org/wiki/Robert%20S.%20Roth | Robert S. Roth (August 21, 1926 – July 16, 2012) was an American materials scientist known for his comprehensive research into the phase diagrams of ceramic materials and the structures of nonstoichiometric compounds.
Education and career
Roth studied geology at Coe College and University of Illinois Urbana-Champaign, where he obtained his PhD in 1951. He worked at the United States Geological Survey as a field assistant, and after his PhD, he joined the National Bureau of Standards (later NIST), where he remained for most of his career. Since 1981, he was a senior editor of the book series Phase Diagrams for Ceramists, a major set of reference books in the field of ceramic materials.
While visiting CSIRO in Melbourne, Australia in the 1960s, Roth collaborated with the Australian materials scientist Arthur D. Wadsley to understand the structures of transition metal oxides, which led to a series of publications. The ordered phases of transition metal oxides exhibiting shear structures are now referred to as the Wadsley-Roth phases.
Honors and awards
Roth received the United States Department of Commerce Gold Medal in 1986. He received the Sosman Award in 1991, the John Jeppson Award in 1995, the Spriggs Phase Equilibria Award in 2003, all from the American Ceramic Society. He received the Buessem Award from the Center for Dielectric Studies in 2001.
Bibliography
References
1926 births
2012 deaths
Coe College alumni
University of Illinois Urbana-Champaign alumni
National Institute of Standards and Technology people
American materials scientists
Solid state chemists
Materials scientists and engineers | Robert S. Roth | [
"Chemistry",
"Materials_science",
"Engineering"
] | 314 | [
"Solid state chemists",
"Materials scientists and engineers",
"Materials science"
] |
70,923,477 | https://en.wikipedia.org/wiki/Note%20G | Note G is a computer algorithm written by Ada Lovelace that was designed to calculate Bernoulli numbers using the hypothetical analytical engine. Note G is generally agreed to be the first algorithm specifically for a computer, and Lovelace is considered as the first computer programmer as a result. The algorithm was the last note in a series labelled A to G, which she employed as visual aids to accompany her English translation of Luigi Menabrea's 1842 French transcription of Charles Babbage's lecture on the analytical engine at the University of Turin, "Notions sur la machine analytique de Charles Babbage" ("Elements of Charles Babbage’s Analytical Machine"). Lovelace's Note G was never tested, as the engine was never built. Her notes, along with her translation, were published in 1843.
In the modern era, thanks to more readily available computing equipment and programming resources, Lovelace's algorithm has since been tested, after being "translated" into modern programming languages. These tests have independently concluded that there was a bug in the script, due to a minor typographical error.
Origin
In 1840, Charles Babbage was invited to give a seminar in Turin on his analytical engine, the only public explanation he ever gave on the engine. During Babbage's lecture, mathematician Luigi Menabrea wrote an account of the engine in French. A friend of Babbage's, Charles Wheatstone, suggested that in order to contribute, Lovelace should translate Menabrea's account. Babbage suggested that she augment the account with appendices, which she compiled at the end of her translation as a series of seven "notes" labelled A-G. Her translation was published in August 1843, in Taylor's Scientific Memoirs, wherein Lovelace's name was signed "A.A.L". In these notes, Lovelace described the capabilities of Babbage's analytical engine if it were to be used for computing, laying out a more ambitious plan for the engine than even Babbage himself had.
Lovelace's notes for the article were three times longer than the article itself. In the first notes, she explores beyond the numerical ambitions that Babbage had for the machine, and suggests the machine could take advantage of computation in order to deal with the realms of music, graphics, and language.
She explains to readers how the analytical engine was separate from Babbage's earlier difference engine, and likens its function to the Jacquard machine, in that it used binary punch cards to denote machine language. In note C, this point is furthered by the fact that simultaneous and iterated actions can be made by the machine, ensuring that any card or collection of cards can be used several times in the solution of a single problem, essentially anticipating modern methods of control flow and looping. These ideas were brought to a head in the final note, G, where Lovelace sought to demonstrate an example of computation.
Note G only made use of only the four arithmetical operations: addition, subtraction, multiplication and division, the implementation of Babbage's vision:
It also uses Babbage's idea of storing information in columns of discs, each denoted by (for variable) and a subscript number denoting which column is being referred to.
Function
Lovelace used a recursive equation to calculate Bernoulli numbers, wherein she used the previous values in an equation to generate the next one. Her method ran thus:
where is a binomial coefficient,
.
Bernoulli numbers can be calculated in many ways, but Lovelace deliberately chose an elaborate method in order to demonstrate the power of the engine. In Note G, she states: "We will terminate these Notes by following up in detail the steps through which the engine could compute the Numbers of Bernoulli, this being (in the form in which we shall deduce it) a rather complicated example of its powers." The particular algorithm used by Lovelace in Note G generates the eighth Bernoulli number (labelled as , as she started with .)
Notation
The table of the algorithm organises each command in order. Each command denotes one operation being made on two terms. The second column states only the operator being used. Variables are notated as "", where the superscript before it represents the amount of different values the variable has been assigned to, and the subscript after it represents the ordinal assignment of the variable, that is which variable it is. (For example, refers to the second assignment of variable number 4. Any variables hitherto undefined have a superscript of 0.) The variables are numbered starting from . The third column tells the computer exactly what command is taking place, (For example, on line 1, the command performed is "" - the first iteration of variable 2 is multiplied by the first iteration of variable 3.) and only incorporates one operation between two terms per line. Column 4 - "Variables receiving results" takes note of where the result of the operation in column 3 should be stored. In this way, any variables in this column have their superscript number incremented by one each time. (e.g. on line 1, the result of is assigned to variables , , and .)
Column 5 states whether either of the variables used in the operation of the command has been changed. Enclosed in curly braces, two rows per command put the original variable on the left side of an equals sign, and the new variable on the other side - that is, if the variable has been changed, its superscript is incremented by one, and if not, it remains the same. (e.g. line three assigns the result of to the second iteration of the variable , and the fifth column reflects this by noting;
has changed, but hasn't.
In column 6, "Statement of Results", the result assigned to the variable in column 4 is shown in its exact value based on the values of the two terms previously assigned. (e.g. on line 1 - - was set at the beginning to be , and was set to be the variable . Therefore, , in mathematical notation.) This column is ostensibly not computed by the engine, and appears to be more to aid clarity and the reader's ability to follow the steps of the program. (For example, line 5 has a fraction being divided by two, which is notated as it being multiplied by a half, probably for coherence and the typographical complexity of a nested fraction.) It also makes use of separate variable notation outside of the program, the and variables, which are multiplied successively to find the final value, , thus:
Beyond this, each successive column shows the values of a given variable over time. Each time a variable either changes, or has its value become relevant by token of its presence as one of the terms in the current command, its value is stated or restated in its respective column. Otherwise, it is marked with an ellipsis to denote its irrelevancy. This presumably mimics the computer's need for only relevant information, thereby tracking the value of a variable as the program parses.
Method
The program sought to calculate what is known by modern convention as the eighth Bernoulli number, listed as , as Lovelace begins counting from .
Error
In operation 4, the division supposedly taking place is "", to be stored in variable . However, the "Statement of results" says that the division should be:
As a matter of fact, the division is the wrong way round; is the second iteration of , as can be seen in operation 2. Likewise, is the second iteration of , as can be seen in operation 3. Thus, operation 4 should not be , but rather . This bug means that if the engine were ever to run this algorithm in this state, it would fail to generate Bernoulli numbers correctly, and would find its final goal value to be .
Modern implementations
Lovelace's program can be implemented in a modern programming language, though due to the above stated error, if transcribed exactly it would return an incorrect final value for . The original program generalised in pseudocode follows as thus:
V[1] = 1
V[2] = 2
V[3] = n (n = 4 in Lovelace's program.)
V[4] = V[4] - V[1]
V[5] = V[5] + V[1]
V[11] = V[5] / V[4]
V[11] = V[11] / V[2]
V[13] = V[13] - V[11]
V[10] = V[3] - V[1]
V[7] = V[2] + V[7]
V[11] = V[6] / V[7]
V[12] = V[21] * V[11]
V[13] = V[12] + V[13]
V[10] = V[10] - V[1]
V[6] = V[6] - V[1]
V[7]= V[1] + V[7]
//Finish Later
The implementation in pseudocode highlights the fact that computer languages define variables on a stack, which obviates the need for tracking and specifying the current iteration of a variable. In addition, Lovelace's program only allowed for variables to be defined by performing addition, subtraction, multiplication or division on two terms that were previously defined variables. Modern syntax would be capable of performing each calculation more concisely. This restriction becomes apparent in a few places, for example on command 6 (). Here Lovelace defines a hitherto undefined variable () by itself, thereby assuming that all undefined variables are automatically equal to 0, where most modern programming languages would return an error or list the variable as null. What she intended was "", but had constrained herself to only using variables as terms. Likewise, in command 8 (), the strict notation of two-term arithmetic becomes cumbersome, as in order to define as 2, Lovelace assigns its value (0) to itself plus (2). It is due to this restrictive notation that is defined thus.
Notes
References
Sources
1843 introductions
Algorithms
Ada Lovelace | Note G | [
"Mathematics"
] | 2,130 | [
"Applied mathematics",
"Algorithms",
"Mathematical logic"
] |
70,924,122 | https://en.wikipedia.org/wiki/9-Euro-Ticket | The 9-Euro-Ticket () was a German scheme through which passengers could travel for 9 euros (€) per month on local and regional transport in all of Germany. The tickets were valid for June, July, or August 2022. The offer aimed at reducing energy use amid the 2021–2022 global energy crisis. Another aim was to ease the cost of living crisis.
The 9-euro ticket was valid in the second class, throughout Germany for all local public transport and on regional trains. It did not include travel on Intercity Express (ICE), Intercity (IC) and Eurocity (EC) trains, and could not be used on FlixTrains or intercity buses.
Funding
The ticket only applied to local and regional transport, which is operated by the states of Germany and municipalities. The German federal government compensated these authorities for their foregone ticket sales. The federal government estimates the cost at 2.5 billion euros.
Effects on traffic
How the 9-euro ticket affected mobility behavior is the subject of accompanying studies, including the study Mobilität.Leben conducted by the TUM with 1,000 participants in Munich. Interim results for the period from June to mid-July showed that 35% of participants used buses and trains more, while 3% used their cars less. A traffic survey conducted by the city of Munich found that car traffic in Munich decreased by 3 percent from May to June instead of (seasonally) increasing by 3 percent. The TUM study continued for the duration of the 9-euro ticket and for a few weeks after it ended. On 5 September 2022, the study group published its 3rd report (on arXiv).
According to a YouGov online survey of 2,038 participants aged 18 and older, conducted in Germany from 22 to 24 August 2022, 28% had bought a 9-euro ticket at least once and 22% had a subscription to public transportation (which included the 9-euro ticket). 31% of participants said they frequently used the 9-euro ticket on routes they would otherwise have taken by car.
Other effects
Since the cost of passenger transportation is a large part of the basket of goods used to calculate average household spending, this has reduced the increase in the consumer price index.
Many people used the ticket's affordability and ease of travel for leisure getawaysaccording to some it enabled them to go on vacation for the first time. On the other hand, especially in June, the 9-euro ticket also led to more overcrowded trains and a heavy workload for train and station staff.
The 9-euro ticket was accompanied by a strong increase in excursion tourism by train to rural tourist areas: according to a special analysis by the Federal Statistical Office, trips by rail in June and July of 30 kilometers or more in rural tourist areas were on average 80 percent higher than in the comparable months of 2019. However, there is also another factor: according to the Federal Statistical Office, consumers in Q2 2022 used the lifting of almost all Corona restrictions to travel and go out more again.
According to an estimate of the Association of German Transport Companies (VDV), the 9-Euro-Ticket offerof which around 52 million tickets were sold in the three monthssaved 1.8 million tons of , almost as much as a speed limit on the autobahns would achieve in an entire year.
Debate and plans about possible successor
In August 2022, Alliance 90/The Greens co-leader Ricarda Lang and others proposed a regional ticket for 29 euros and a nationwide ticket for 49 euros a month as successor for the 9-Euro-Ticket after August 2022.
Christian Lindner, the federal finance minister and party leader of the Free Democratic Party (FDP), initially expressed fundamental opposition. While his party colleague, the federal minister for digital and transport Volker Wissing saw the 9-Euro-Ticket as a success, Lindner rejected these low-price tickets also on ideological grounds, calling them part of a "Freebie mentality" () on Twitter. The Saarland Ministry of Transport criticized Lindner's stance with reference to climate protection targets.
Like the Federal Ministry of Transport, the SPD parliamentary group in the Bundestag is calling for the federal states to contribute to the costs and its vice-chairman Detlef Müller proposed the elimination or reduction of environmentally harmful tax subsidies in the area of road transport as a feasible way to finance the federal share for a successor scheme. Much of the debate focused on the "Dienstwagenprivileg", a €3 billion tax benefit for take-home vehicles, which primarily benefits high earners.
On 31 August, finance minister Lindner also signaled his approval of a successor scheme to the 9-euro ticket on condition that the federal states contribute to the costs.
After a closed-door meeting in Schloss Meseberg, the governing coalition of SPD, Greens and FDP announced in early September that, as part of the planned third relief package, it would also introduce a successor to the 9-euro ticket; the tickets are to cost around 49 to 69 euros a month. The governing coalition wants to make 1.5 billion euros available per year for this, but demands that the federal states contribute at least the same amount.
In May 2023, Germany introduced the Deutschlandticket, a monthly subscription costing 49 euros, as a successor to the 9-Euro-Ticket. While not as inexpensive, the Deutschlandticket aims to encourage public transport use and contribute to climate protection. The program's digital-only subscription model has drawn both praise for its modernization and criticism for accessibility concerns among less tech-savvy users. This transition reflects ongoing debates about sustainable funding and equitable access to public transportation in Germany.
49 euro monthly ticket
On 13 October 2022, the transport ministers of the federal states and Federal Transport Minister Wissing announced that they had agreed on a successor ticket dubbed , which is expected to be available from January 2023 and cost 49 euros per month. At this time, the financing scheme remained unclear, as the states demanded the federal government to contribute more money.
At the end of November 2022, the transport ministers reaffirmed the commitment to the monthly ticket for 49 euros and it is planned to start in April 2023, an earlier start already in January was considered too timely for implementation. But the planned start has been further delayed by one month as there was still opposition from the local and regional transportation services like the Munich MVV that wanted more refunding from the federal and the state governments.
On 31 March 2023, the Bundesrat approved the bill passed by the Bundestag for a nationwide ticket for local and regional public transportation at a monthly price of 49 euros.
The monthly tickets started in May 2023, but can only be purchased by subscription. There are no traditional paper cards for the subscription – with the possible exception of the start-up phase; the users have to authenticate digitally (either via smartphone app or chip card).
Berlin successor
Berlin offered a €29 ticket for October, November and December 2022. It was only available as part of a one-year subscription, with the right to cancel after three months. The fare reduction (from €86) was paid for by the state of Berlin.
See also
365-Euro-Ticket
Free public transport
References
External links
THE MOST IMPORTANT THINGS TO KNOW ABOUT THE 9-EURO TICKET (www.rmv.de)
Visit Berlin with a public transport ticket valid for one month for only 9 Euros! (www.viveberlintours.com)
9-Euro-Ticket (www.bahn.com)
Germany’s €9 train tickets scheme ‘saved 1.8m tons of CO2 emissions’. The Guardian. Published 30 August 2022.
Public transport in Germany
2022 in Germany
2022 in transport
Emissions reduction
Energy crises
Euro
Public transport tickets
Scholz cabinet
Environmental policies approved in 2022
2022 in Berlin | 9-Euro-Ticket | [
"Chemistry"
] | 1,622 | [
"Greenhouse gases",
"Emissions reduction"
] |
70,924,498 | https://en.wikipedia.org/wiki/Reginald%20Otto%20Kapp | Reginald Otto Kapp (2 August 1885-20 February 1966) was a professor of electrical engineering at UCL.
He was appointed to the Pender chair in 1935.
References
External links
www.reginaldkapp.org
Portrait in the National Portrait Gallery
Electrical engineers
1885 births
1966 deaths
Electrical engineering academics
Academics of University College London | Reginald Otto Kapp | [
"Engineering"
] | 66 | [
"Electrical engineering",
"Electrical engineers"
] |
70,924,983 | https://en.wikipedia.org/wiki/Eva%20Sorensen | Eva Sorensen is a British chemical engineer. She was appointed in 2020 as interim head of the Department of Chemical Engineering while Marc-Olivier Coppens was on a year sabbatical. She is the first female to lead the department.
In 2018 she was honoured by the Institution of Chemical Engineers (IChemE) with the Frank Morton Medal for promoting best practice in chemical engineering education. The citation read "Medal awarded to Professor Eva Sorensen for being a key driver for innovation in teaching and learning, inside and outside her own institution. She was noted by the committee to have worked tirelessly over several decades to promulgate best practice in chemical engineering education."
Sorensen was appointed Member of the Order of the British Empire (MBE) in the 2023 Birthday Honours for services to education and chemical engineering.
In 2024 she was elected a fellow of the Royal Academy of Engineering
References
Further reading
Academics of University College London
British chemical engineers
Living people
Year of birth missing (living people)
Members of the Order of the British Empire
Women chemical engineers
21st-century British women engineers
Fellows of the Royal Academy of Engineering
Female fellows of the Royal Academy of Engineering | Eva Sorensen | [
"Chemistry"
] | 231 | [
"Women chemical engineers",
"Chemical engineers"
] |
70,925,338 | https://en.wikipedia.org/wiki/Ammonium%20ozonide | Ammonium ozonide is an oxygen rich molecule containing an ammonium cation (NH4+) and an ozonide anion (O3−). Ammonium ozonide, like alkali ozonides, is a red solid. Ammonium ozonide is stable at low temperatures, but it decomposes to ammonium nitrate at temperatures above -70 °C.
Preparation and decomposition
Ammonium ozonide is made by bubbling gaseous ozone through liquid ammonia at -110 °C. This method suffers from a low yield.
Ammonium ozonide decomposes into ammonium nitrate, oxygen gas, and water. If the above reaction is done at high temperatures, these decomposition products result immediately and no ozonide is formed.
References
Ozonides
Ammonium compounds | Ammonium ozonide | [
"Chemistry"
] | 161 | [
"Salts",
"Ammonium compounds",
"Inorganic compounds",
"Inorganic compound stubs"
] |
70,925,355 | https://en.wikipedia.org/wiki/Polydactyly-myopia%20syndrome | Polydactyly-myopia syndrome, also known as Czeizel-Brooser syndrome, is a very rare genetic disorder which is characterized by post-axial polydactyly on all 4 limbs and progressive myopia. Additional symptoms include bilateral congenital inguinal hernia and undescended testes. It has only been described in nine members of a 4-generation Hungarian family in the year 1986. This disorder is inherited in an autosomal dominant manner.
References
Genetics | Polydactyly-myopia syndrome | [
"Biology"
] | 106 | [
"Genetics"
] |
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