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70,527,312 | https://en.wikipedia.org/wiki/NGC%204393 | NGC 4393 is a spiral galaxy about 46 million light-years away in the constellation Coma Berenices. It was discovered by astronomer William Herschel on April 11, 1785. It is a member of the NGC 4274 Group, which is part of the Coma I Group or Cloud.
Physical characteristics
NGC 4393 is a flocculent spiral galaxy, with chaotic, fragmented and unsymmetric arms. IC 3329, an HII region in NGC 4393, was discovered by astronomer Max Wolf on March 23, 1903. It was described as "very faint, small, irregular figure, attached to (NGC) 4393".
NGC 4393 hosts a pseudo-bulge, a type of galactic bulge which is more similar to a spiral galaxy in that it has one or more characteristics of disk galaxies. These include having flatter shapes than those of classical bulges, large ratios of ordered motions of stars rather than random motions of stars, small velocity dispersions of stars with respect to the Faber-Jackson correlation between velocity dispersion and bulge luminosity, a spiral structure or nuclear bar in the bulge part of the light profile, nearly exponential brightness profiles, and starbursts.
Nuclear Star Cluster
The central region of NGC 4393 is host to a nuclear star cluster with a mass of 0.4048 ± 0.0819 × 106 M☉, and a diameter of ~.
See also
List of NGC objects (4001–5000)
Coma I
References
External links
4393
040600
Coma Berenices
Astronomical objects discovered in 1785
Flocculent spiral galaxies
07521
Coma I Group
NGC 4393 | NGC 4393 | [
"Astronomy"
] | 342 | [
"Coma Berenices",
"Constellations"
] |
70,527,346 | https://en.wikipedia.org/wiki/Rixosome | The rixosome is a protein complex involved in RNA degradation, ribosomal RNA (rRNA) processing, and ribosome biogenesis. It was named after the S. cerevisiae gene RIX1. The rixosome is associated with human PRC1 and PRC2 complexes. The interaction with PRC1 appears to be through the RING1B domain of PRC1 based on mutational analysis. The co-localization of the rixosome and PRC complex suggest a role in the rixosomal degradation of nascent RNA to contribute to the silencing of many Polycomb targets in human cells. Regulation of the interaction with the PRC1 complex is mediated by SENP3 which deSUMOylates several rixosome subunits.
Components
Rixosome complex contains the following components:
WD repeat domain 18
LAS1L
TEX10
PELP1
References
Protein complexes | Rixosome | [
"Chemistry"
] | 185 | [
"Biochemistry stubs",
"Protein stubs"
] |
70,529,013 | https://en.wikipedia.org/wiki/Canadian%20Nuclear%20Laboratories%20Research%20Facilities | Canadian Nuclear Laboratories (CNL) research facilities are located in Chalk River, Ontario, Canada, approximately 180km north-west of Ottawa. There are three new additions to the site. The Logistics Warehouse (5016 sqm / 54000 sqft) contains a large reception space, offices, and storage. The Support and Maintenance Facility (4800 sqm / 51670 sqft) houses equipment, offices, and flexible open spaces. The Science Collaboration Centre (8198 sqm / 88240 sqft) has studios, laboratories, and administrative spaces.
CNL is a nuclear technology and research institute. Their ageing facilities required an overhaul to continue innovation. The campus contains over 300 buildings across a 3700 hectare plot of land along the Ottawa River. Design firm HDR was the architect.
History
Historically, the Chalk River Laboratories was a nuclear power plant and advanced nuclear research facility. CNL began developing nuclear technology in the late 1940's and early 1950's. The government owned company Atomic energy of Canada Limited (AECL) took over Chalk River Nuclear Laboratories in 1952, but today the site remains operated through contractors such as CNL. This is referred to as GoCo management, government owned and contractor operated. The research led to the development of the CANDU reactor. Other research included fuels, hydrogen production, storage and handling of radiation, and more recently alpha therapies medical isotope treatment for cancer. In 2014, Ontario became the first jurisdiction in North America to leave behind coal fired power plants and fully rely on nuclear power and renewable energies. In 2016 a $1.2 billion dollar investment plan over ten years was released by the Government of Canada. The investment plan required the decommissioning of 120 aged facilities and designing new centres.
Design
The Logistics Warehouse is the new public face to the campus. It finished construction in September 2020 at $30.6 million dollars. This is a two storey building that houses spaces for reception and information, offices, and storage. The front half of the building is the public space, with storage in the back half. The front facade design is mostly transparent using glazing with wood slatting in front of the curtain walls.
The Support and Maintenance Facility is also a two storey building. This is their manufacturing and servicing depot. This facility was completed in March 2021 at $32.8 million dollars. The interior of the warehouse has entirely exposed services and structure. The facade on this building is mostly solid, with thin glazing that frames the surrounding forest.
The Science Collaboration Centre is a six storey, multi-use building that will act as the heart of the campus. Its projected completion date is Spring 2023 with a budget of $62 million dollars. The building will feature three open plan studios, offices, laboratories, and data storage. The facade design is mostly glass which will reveal the active spaces inside as well as the wood structure.
References
Research institutes in Canada
Buildings and structures in Renfrew County
Sustainable architecture
Wooden buildings and structures | Canadian Nuclear Laboratories Research Facilities | [
"Engineering",
"Environmental_science"
] | 609 | [
"Sustainable architecture",
"Environmental social science",
"Architecture"
] |
70,531,855 | https://en.wikipedia.org/wiki/David%20Manolopoulos | David Eusthatios Manolopoulos (born 14 December 1961) is a Professor of Theoretical Chemistry at University of Oxford. His research focuses on the computational modeling of the dynamics of elementary chemical reactions in the gas phase and quantum mechanical effects in chemical dynamics. His research highlights include work on path integral approach to molecular dynamics and chemical topics as diverse as fullerenes, ring polymers, reactive scattering, and more recently, the molecular and quantum mechanism of avian magnetoreception.
He was awarded the Marlow Award and the Corday–Morgan Prize. He has been involved with editing the Journal of Chemical Physics.
Bibliography
See also
Quantum biology
External links
Personal site at University of Oxford
References
Living people
Physical chemists
Fellows of the Royal Society
Academics of the University of Oxford
Alumni of the University of Cambridge
Academics of the University of Nottingham
1961 births
People from Gillingham, Kent
Chemical physicists | David Manolopoulos | [
"Chemistry"
] | 176 | [
"Chemical physicists",
"Physical chemists"
] |
70,532,420 | https://en.wikipedia.org/wiki/Boot%20scraper | A boot-scraper, door scraper, mud scraper, or decrottoir is a device consisting of a metal blade, simple or elaborate, permanently attached to the wall or to the sidewalk at the entrance to a building to allow visitors to scrape snow, mud, leaves, or manure off the soles of their footwear before entering.
Appearance
The simplest shoe scrapers could be a rectangular sheet of metal, a horizontal bar, or thick steel wire, but many had more complex shapes made of cast iron or wrought iron with horizontal center piece to scrape off the sole, vertical scraping surfaces to clean the sides of the boot, and other shapes to access concave area by the heel.
On building entrances, boot scrapers could be cemented into the pavement, protrude from a house walls, hide in a niche built into the facade, or sometimes integrated into wrought-iron banisters.
History
The scrapers appeared at the end of the 18th century, at the same time as the sidewalks and abounded in the 19th century big cities, in the times of horse-drawn carriages and dirt roads. Originally placed directly on foot paths, some were banned as a danger to public safety and placed in niches in the facades.
Through the 20th century, the scrapers of European cities fell into disuse and many were removed during roadworks, or salvaged for ferrous metals.
Notable locations
At the British Prime Minister's office, 10 Downing Street in London, there are two ornate cast-iron Victorian shoe scrapers symmetrically on the right and left of the door.
On the top step of the front staircase of Goethe's house in Weimar there is a simple shoe scraper made of a rectangular plate.
In New York City's Greenwich Village, shoe scrapers are integrated into the banisters of some historic townhouses.
On Beacon Hill, Boston, Massachusetts, shoe scrapers are a feature of most historic houses.
References
External links
Architectural elements | Boot scraper | [
"Technology",
"Engineering"
] | 402 | [
"Building engineering",
"Architectural elements",
"Components",
"Architecture"
] |
70,532,824 | https://en.wikipedia.org/wiki/V346%20Centauri | V346 Centauri is a variable star in the constellation Centaurus. An Algol-type eclipsing binary, its apparent magnitude has a maximum of 8.50, dropping to 8.77 during primary eclipse and to 8.72 during secondary eclipse, the latter being a total eclipse. From parallax measurements by the Gaia spacecraft, the system is located at a distance of about 2300 parsecs (7400 light-years), which is consistent with earlier estimates, based on its luminosity, of 2380 parsecs. The system is a confirmed member of the open cluster Stock 14, which contains many other young OB stars.
Both stars in the system are hot B-type stars, with spectral types of B0.5IV and B2V. The primary star shows signs of being evolved, while the secondary is still in the main sequence. In 1936, William O'Leary and Daniel Joseph Kelly O'Connell announced their discovery that the star, then known as CPD-61° 2551, is a eclipsing binary star. It was given its variable star designation, V346 Centauri, later that same year. Due to the eclipsing and double-lined nature of the system, the physical elements of the stars can be determined with high precision. The primary star has a mass of 12 times the solar mass, radius of 8.3 times the solar radius, and an effective temperature of about 27,000 K. The secondary star is smaller and cooler, with 8.5 times the solar mass, 4.1 times the solar radius, and temperature of 25,000 K. In visible light, the primary contributes about 84% of the system's luminosity, while the secondary contributes the rest (16%). There is no evidence in the spectrum or the light curve for a third star in the system.
The average separation between the stars is about 39 solar radii. The orbit of the system has a moderate eccentricity of 0.287 and is inclined by 84.4° in relation to the plane of the sky. It displays apsidal precession with a period of years, which means that the argument of periapsis has a cyclical variation with this period. The times of minimum light of the system indicate that the orbital period changed suddenly around the year 1965, decreasing from 6.322123 to 6.321843 days (a decrease of 24 seconds). The reason for this is unknown.
References
Algol variables
Centaurus
B-type subgiants
B-type main-sequence stars
Durchmusterung objects
101837
Centauri, V346 | V346 Centauri | [
"Astronomy"
] | 548 | [
"Centaurus",
"Constellations"
] |
70,533,590 | https://en.wikipedia.org/wiki/Ahmad%20Salahuddin | Ahmad Salahuddin (7 July 1937 – 26 November 1996) was an Indian biochemist who served as a professor of biochemistry and department chairman (1984–1996) at Aligarh Muslim University (AMU) Aligarh, India. He was a Founder Director of Interdisciplinary Biotechnology Unit at AMU in 1984.
Early life
Salahuddin was born on 7 July 1937 in Jairajpur, Azamgarh, Uttar Pradesh. His father, Fazlul Bari, was a teacher at the Shibli National College, Azamgarh where he received his early education, and he later completed his undergraduate and master's degrees in 1955 and 1957 in chemistry from the Aligarh Muslim University. Initially as a research student, he took interest in physical chemistry, obtaining his PhD degree in chemistry from Aligarh Muslim University Aligarh (1962).
Career
He received his second Ph.D. degree at Duke University where he was a Fulbright Scholar from 1964 to 1968. He worked in the laboratory of Charles Tanford, Department of Biochemistry in the protein folding area focussing his career on the folding thermodynamics and
kinetics, properties of the native and the unfolded proteins. His early collaborative work in uncovering residual native protein structure, following treatment with heat, acid (low pH) experimentally in a number of model proteins in his lab was published in 1967. He actually performed equilibrium unfolding studies on ribonuclease protein in guanidine hydrochloride, the findings of which were acceptable for the aforementioned Ph.D. degree in biochemistry by Duke University (1968).
Salahuddin returned to AMU Aligarh and joined the Department of Biochemistry, Faculty of Medicine, J.N. Medical College in 1968 as a reader. Salahuddin was present at the foundation ceremony of the new IBU Building on 15 January 1986. The event was inaugurated by Abdus Salam. He performed a critical role toward the establishment of the Interdisciplinary Biotechnology Institute for Modern Biological and Biotechnological Education at Aligarh along with the AMU administration in 1984.
Research
Egg white ovalbumin: The unfolding of ovalbumin, a 45 kDa protein, as a function of guanidine hydrochloride (0-6M) occurred reversibly in one step. The protein fractions in native (N) and the denatured states (D) were characterized by UV spectrometry and viscosity measurements at defined temperatures in buffer pH 7.0. The thermodynamics of folding and possibly kinetics followed a two state transition (N->D). The data were consistent with the fact that the native state was stabilized by hydrophobic effect in aqueous solution; this effect was diminished by introducing Guanidine hydrochloride to protein solution with concomitant transition to denatured state, random coil conformation similar to a nascent polypeptide chain.
Egg white Ovomucoid: The unfolding of ovomucoid (N), a domain containing 28 kDa protein, by guanidine hydrochloride did not proceed in a single step but occurred in two steps; the transition at low denaturant was associated with an intermediate, native-like, structure (X), and at high denaturant, protein existed in random coil structure (D). The reversible unfolding at each step (N->X->D) followed a two state transition pattern, albeit with somewhat different folding rates for the intermediate and native structures (1978). The studies in his lab indicated that in vivo protein folding may not be explained by the amino acid sequence of an individual protein alone. Independently, the molecular biology of chaperones succeeded in the identification of additional folding factors in 1989. The latter studies marked the beginning of modern protein folding with manipulation in human health.
Awards and honours
Salahuddin was President of Society of Biological Chemists SBC (India) from 1989 to 1990; a Member of the editorial board of Indian Journal of Biochemistry and Biophysics(1985–1988); Visiting Associate Professor, University of Maryland 1975; Member of Protein Society, Bethesda, USA(1995-1997); Member of the New York Academy of Science, New York(1995-1996); Member of the executive committee of the Society of Biological Chemists, India(1974-1975); Member of the executive committee of Indian Biophysical Society, India (1991–1993); Member of the Guha Research Conference, India (1987–1992); and Member of Sigma Xi (USA).
Death
Salahuddin died on 29 November 1996 at the age of 59 after a difficult illness. His passing away saddened his family and his students. Eulogies by his former students were read at the Annual meeting of the Aligarh Alumni Association Washington DC;
by others at a session at AMU Aligarh on 3 Jan 2019. At his death he was survived by his wife and two daughters.
Selected publications
References
External links
Ahmad Salahuddin's pubmed publications
Academic staff of Aligarh Muslim University
Scientists from Uttar Pradesh
1937 births
1996 deaths
20th-century Indian biologists
20th-century Indian chemists
People from Azamgarh
People from Azamgarh district
Aligarh Muslim University alumni
20th-century Indian Muslims
People from Aligarh
Indian biochemists
Indian immunologists
Indian medical researchers
Duke University alumni
Biochemists | Ahmad Salahuddin | [
"Chemistry",
"Biology"
] | 1,099 | [
"Biochemistry",
"Biochemists"
] |
70,533,707 | https://en.wikipedia.org/wiki/Moder%20humus | Moder is a forest floor type formed under mixed-wood and pure deciduous forests. Moder is a kind of humus whose properties are the transition between :mor humus and mull humus types. Moders are similar to mors as they are made up of partially to fully humified organic components accumulated on the mineral soil. Compared to mulls, moders are zoologically active. In addition, moders present as in the middle of mors and mulls with a higher decomposition capacity than mull but lower than mor. Moders are characterized by a slow rate of litter decomposition by litter-dwelling organisms and fungi, leading to the accumulation of organic residues. Moder humus forms share the features of the mull and mor humus forms.
Properties
Moders develop in semiarid, temperate, and Mediterranean climates. Moders' chemical characteristics show low acidity, total carbon, carbon-nitrogen ratio, cation exchange capacity, and high total nitrogen and base saturation. Moders have a higher availability of nutrients than mors.
Formation of moder humus forms
Morders form in deciduous forest situations when the soil has few micro-organisms, bacteria, and invertebrates, such as earthworms, to decompose the organic matter on the soil surface. The organic matter accumulation horizon could identify by capitalized letters. It is generally possible to observe three distinct "sub-layers" or horizons designated by the litter (L) *, fermentation (F) *, and humus (H) * layers.
Identify different layers for moder
"L" litter: A horizon is defined by accumulating primary leaves (and needles), twigs, and woody materials, with the original structures visible.
"F" Fermentation: A horizon defined by the buildup of partially decomposed organic matter generated primarily from leaves, twigs, and woody materials. Some of the original structures are difficult to identify, and materials may have been pounded into small pieces or particles in part by soil fauna, as in a "MODER".
"H" Humus: A horizon defined by the accumulation of disintegrated organic matter in which the original structures are undetectable. It differs from the "F" horizon as more humification due to organisms' actions. It can partially merge into the mineral soil such as the "MODER".
The Fa horizon is used to distinguish moder. These layers are mostly made up of partially decomposed plant remains broken or comminuted by soil fauna and are loosely organized rather than matted like the Fq horizons. An abundance of fine roots can sometimes result in a matte appearance. A distinctive aspect of the Fa horizon and its loose nature is the abundance of soil fauna droppings, which can be seen with high magnification. Centipedes, millipedes, collembola, mites, isopods, and various insect larvae all come from these droppings. The fragmentation of plant residues by soil fauna facilitates a faster rate of decomposition. Bacteria, actinomycetes, and protozoa are progressively contributing to the breakdown process, although fungi continue to play an important role
Soil fauna break plant residues into non-compact, loose arrangements mainly constituted of faunal droppings, which make up friable Fz horizons in moders. The moder order, like mors, accumulates organic matter above the mineral horizons. Fungal mycelia are reasonably expected, and plant residues may appear somewhat matted. However, many small insect droppings can still be observed. In most Moder humus types, H d horizons can be observed. However, mor humus types might have similar horizons. This trait is not considered diagnostic of Moders. H horizons have no distinct, differentiating characteristics that would indicate whether they are from Mors or Moders, according to the observation of humus from micro-morphology.
Moder humus form may include only the Ah horizon or ectorganic horizons below end- organic horizons. Fine humus elements have permeated the mineral soil on this horizon. Although soil animals may carry organic matter into the upper region of this horizon, this will only happen over a short distance. The upper limit of the Ah horizon is often gradual.
References
Forest ecology
Soil biology | Moder humus | [
"Biology"
] | 871 | [
"Soil biology"
] |
70,533,744 | https://en.wikipedia.org/wiki/Cheluviation | Cheluviation is the process in which the metal ions in the upper layer of the soil are combined with organic ligands to form coordination complexes or chelates, moving downwards through eluviation and then depositing.
Metal ions that can participate in chelation include Fe, Al, Mn, Ca, Mg and trace elements in soil, while the organic ligands combined with these metal ions come mainly from the soil organic matter. Soil organic matter includes relatively stable complex organic compounds (such as lignin, protein, humus, etc.), as well as some simple organic acids and intermediate products of microbial decomposition of organic matter. These organic coordination compounds all contain active groups to varying degrees. Chain organic coordination compounds are complexed with metal ions to generate complexes, and these generated complexes containing multiple coordination atoms in a cyclic structure with metal ions are called chelates. The stability of the chelate is related to the number of atoms in the chelate ring, the stability constant of the chelation reaction, and the concentration of organic chelating agents and metal ions. The chelates produced by fulvic acid and metal ions in soil humus have strong leaching and deposition effects, and therefore are an important manifestation of soil cheluviation, which is generally resulting in the formation of gray-white leaching layers and dark brown/red deposited layer.
Dissolution and chelation of metal elements
Organic acids have the ability to dissolve soil minerals, and can destroy silicate minerals and iron and aluminum oxides, so that metal ions are precipitated and complexed with organic complexing agents through ion exchange, surface absorption, and chelation-reaction mechanisms. For example, at low pH, a large number of metal ions are complexed with organic acids. When the organic acid occupies the coordination position of the metal ion, it can prevent the precipitation and crystallization of the metal oxide and increase its solubility. Conversely, at high pH (e.g. 7–8), dissolved metal ions, such as Fe(III), will precipitate out of the solution as insoluble complexes.
Eluviation of chelate compounds
The eluviation of chelate compounds is the downward movement of soil chelates. The eluviation of chelate compounds can be affected by:
Acidity. Organic acids produced under acidic conditions can increase the solubility of metal elements such as iron and aluminum, thereby enhancing soil eluviation. Iron and aluminum are easily leached at low pH. As the pH increases, ferric hydroxide and aluminum hydroxide compounds precipitate.
Redox conditions. Under reducing conditions, more organic acids are produced and metal ions are reduced to soluble metal complexes that migrate into the soil. Under oxidative conditions, metal ions are easily precipitated, and the chelate is easily polymerized, thereby separating the chelate from the metal ions.
Soil texture. Clay has a certain adsorption capacity for chelates, which weakens the leaching of complexes. On the other hand, soils with a coarse texture and water-saturated soils will likely enhance the leaching effect of chelates.
References
Soil chemistry
Coordination chemistry | Cheluviation | [
"Chemistry"
] | 653 | [
"Soil chemistry",
"Coordination chemistry"
] |
70,534,081 | https://en.wikipedia.org/wiki/Michael%20Start | Michael Start (born 27 October 1960) is a British automata maker and restorer. He trained in Technical Horology at Hackney College in London, and now specialises in the conservation and restoration of antique automata, with a focus on 19th Century automata.
Michael Start is co-founder of "The House of Automata". Together with his wife, Maria Start, they restore and deal in antique automata. Founded in London, it is now based in the North of Scotland, where “The House of Automata” operates from a workshop studio.
Media and television
Michael Start has worked as a consultant to the media, advising on automata and horology for screen. In 2011, Start designed the mechanism for the automaton that was featured in the Martin Scorsese screen adaptation of ‘’Hugo’’.
Michael Start features as an expert on Salvage Hunters- The Restorers, produced by Quest and Discovery Channel. Together with his wife Maria, they appear in Series 3, 4 and 5, as experts in Automata restoration.
References
External links
The House of Automata
The House of Automata
The House of Automata - YouTube
Login • Instagram
Salvage Hunters on Quest discovery+ | Stream 55,000+ Real-Life TV Episodes
Michael Start
Automata Convention
1960 births
Living people
Automata (mechanical)
Conservator-restorers
21st-century British people | Michael Start | [
"Engineering"
] | 283 | [
"Automata (mechanical)",
"Automation"
] |
70,535,056 | https://en.wikipedia.org/wiki/F.%20Ann%20Walker | Frances Ann Walker was an American chemist known for her work on heme protein chemistry. She was an elected fellow of the American Association for the Advancement of Science and the American Chemical Society.
Education and career
Walker was born in Ohio and grew up there, graduating from Adena High School in 1958. Walker has a B.A. in chemistry from College of Wooster (1962). In 1966 she earned her Ph.D. in chemistry from Brown University. From 1967 until 1970 she was a postdoctoral fellow at the University of California, Los Angeles, and an assistant professor at Ithaca College. She then moved to San Francisco State University, where she was promoted to professor in 1976. Subsequently, she moved to the University of Arizona, where she was named regents professor in 2001, and then she retired in 2013.
Research
Walker's research centered on bio-inorganic chemistry, especially heme protein chemistry. Walker examined proteins in bloodsucking insects and cytochromes that transfer energy between cells. Walker's early work was on porphyrins and their complexation with iron. She was able to obtain structural information about metal binding proteins. A portion of her work relied on nuclear magnetic resonance, especially paramagnetic nuclear magnetic resonance spectroscopy, which she used to examine model heme and systems with proteins coupled to heme.
Selected publications
Awards and honors
Walker was elected a fellow of the American Association for the Advancement of Science in 1984. In 2000 she received the Garvan–Olin Medal for scientific accomplishments by a woman chemist from the American Chemical Society. In 2006 she received the Alfred Bader Award in Bioinorganic Chemistry, and in 2011 she was elected a fellow of the American Chemical Society. The Society of Porphyrins and Phthalocyanines awarded her the Eraldo Antonini Award for lifetime achievement award in 2020.
References
1940 births
2022 deaths
Scientists from Ohio
Women chemists
American inorganic chemists
University of Arizona faculty
Fellows of the American Association for the Advancement of Science
Brown University alumni
College of Wooster alumni
Fellows of the American Chemical Society | F. Ann Walker | [
"Chemistry"
] | 419 | [
"American inorganic chemists",
"Inorganic chemists"
] |
70,535,361 | https://en.wikipedia.org/wiki/Kathlyn%20A.%20Parker | Kathlyn Ann Parker is a chemist known for her work on synthesis of compounds, especially organic compounds with biological roles. She is an elected fellow of the American Chemical Society and a recipient of the Garvan–Olin Medal in chemistry.
Education and career
Parker graduated from Senn High School in Chicago. She went on to receive a B.A. from Northwestern University (1966). While in college she won an award from the student chapter of the American Institute of Chemists for her essay "Chemistry as a Profession" making her the first woman to receive this award. She earned her Ph.D. from Stanford University in 1970. Following her Ph.D. she was a postdoctoral research at Columbia University. From 1973 until 2001 Parker was in the chemistry department at Brown University. In 2001 she moved to Stony Brook University, and in 2017 she was named a distinguished professor at Stony Brook University.
Research
Parker is known for her work in the field of organic synthesis, where she works on the construction of natural products through methods that allow for efficient synthesis of known organic compounds.
Selected publications
Awards and honors
In 1987 Parker was a fellow of the John Simon Guggenheim Foundation. In 2009 the Parker was elected a fellow of the American Chemical Society and she received the Francis P. Garvan-John M. Olin Medal from the American Chemical Society. In 2017 she received the Arthur C. Cope Scholar Award in recognition of her work synthesizing organic compounds.
References
Living people
Northwestern University alumni
Stanford University alumni
Stony Brook University faculty
Women chemists
Organic chemists
Fellows of the American Chemical Society
Year of birth missing (living people)
American women chemists
Chemists from Illinois | Kathlyn A. Parker | [
"Chemistry"
] | 335 | [
"Organic chemists"
] |
64,637,511 | https://en.wikipedia.org/wiki/Mars%20jar | A Mars jar or Mars simulation chamber is a container that simulates the atmosphere of the planet Mars. It is used in astrobiology experiments to determine what kind of life on Mars might be viable.
Features
Mars jars have evolved from simple glass containers that resembled kitchen jars in the 1950s to sophisticated temperature-controlled pressure vessels that are now more commonly called "Mars environmental simulation chamber" or "Mars atmosphere simulation chamber". In such devices, a variety of aspects of the Martian environment can be replicated, such as atmospheric composition and pressure, surface materials, temperature cycles and solar radiation.
History
The concept and the name "Mars jar" originate with Hubertus Strughold, a German physiologist and pioneering space medicine researcher. Strughold described Mars jars in his 1953 publication The Green and Red Planet: A Physiological Study of the Possibility of Life on Mars, in which he also coined the term "astrobiology". By 1956, Mars jars were part of U.S. Air Force research projects into crewed Mars missions.
The concept was popularized outside military circles in 1957 by the biologist Joshua Lederberg, who proposed it to NASA leaders, and then by the astrophysicist and science educator Carl Sagan, who featured Mars jars in his TV shows. According to the science historian Jordan Bimm, Strughold's work was not mentioned in later descriptions of Mars jars because civilian scientists wanted to avoid association with the military and with Strughold's involvement in human experimentation in Nazi Germany.
References
Astrobiology
Atmosphere of Mars | Mars jar | [
"Astronomy",
"Biology"
] | 311 | [
"Origin of life",
"Astrobiology stubs",
"Speculative evolution",
"Astrobiology",
"Astronomy stubs",
"Biological hypotheses",
"Astronomical sub-disciplines"
] |
64,638,402 | https://en.wikipedia.org/wiki/Donald%20S.%20Passman | Donald Steven Passman (born March 28, 1940, in New York City) is an American mathematician, specializing in ring theory, group theory, and Lie algebra theory.
Biography
After attending the Bronx High School of Science, Passman matriculated at the Polytechnic Institute of Brooklyn, where he graduated with B.S. in 1960. He then became a graduate student in mathematics at Harvard University, where he graduated with M.A. in 1961 and Ph.D. in 1964. His doctoral dissertation was written under the supervision of Richard Brauer. Passman was an assistant professor from 1964 to 1966 at the University of California, Los Angeles (U.C.L.A.) and from 1966 to 1969 at Yale University. At the University of Wisconsin–Madison, he was from 1969 to 1971 an associate professor, from 1971 to 1995 a full professor, and from 1995 to 2011 the Richard Brauer Professor of Mathematics. In 2011 he retired as professor emeritus.
Passman has written 7 books and more than 180 research publications. He has given over 70 invited addresses, not only in North America but also in Europe, Brazil, Israel, and Turkey. He has been an editor for several mathematical journals, including the International Journal of Mathematics, Game Theory and Algebra (1991–2013), Beiträge zur Algebra und Geometrie (1993–2013), Algebras and Representation Theory (2001–2011), and the Journal of Algebra and its Applications (2001–2016).
In 1963 Passman married Marjorie Mednick. They have two children, Barbara and Jonathan, and five grandchildren, Samuel, Rebecca, Abraham, Jordan and Eve.
Awards and honors
1977 — Lester R. Ford Award for 1976 article What is a group ring?
1989 — Plenary speaker, Canadian Math Society summer meeting, Windsor Ontario, June 1989
2000 — Deborah and Franklin Haimo Award for Distinguished College or University Teaching of Mathematics, Mathematical Association of America
2005 — Conference, held June 10–12 2005 at the University of Wisconsin–Madison, in honor of Donald S. Passman
2012 — elected a 2013 Fellow of the American Mathematical Society
Books
Permutation Groups, Benjamin, New York, (1968), pbk edition, Dover, Mineola, (2012).
Infinite Group Rings, Marcel Dekker, New York, (1971).
The Algebraic Structure of Group Rings, Wiley-Interscience, New York (1977), [Krieger, Malabar, (1985)], pbk edition, Dover, Mineola, (2011).
Group rings, Crossed Products and Galois Theory, CBMS Conference Notes, AMS, Providence, 1986.
Infinite Crossed Products, Academic Press, Boston, (1989), pbk edition, Dover, Mineola, (2013).
A Course in Ring Theory, Wadsworth, Pacific Grove, (1991), pbk edition, Chelsea-AMS, Providence, (2004).
Lectures on Linear Algebra, World Scientific, Singapore, (2022),
References
External links
1940 births
Living people
20th-century American mathematicians
21st-century American mathematicians
Algebraists
Group theorists
Fellows of the American Mathematical Society
The Bronx High School of Science alumni
Harvard University alumni
University of Wisconsin–Madison faculty | Donald S. Passman | [
"Mathematics"
] | 655 | [
"Algebra",
"Algebraists"
] |
64,638,887 | https://en.wikipedia.org/wiki/Tower%20crane%20anti-collision%20system | A tower crane anti-collision system is an operator support system for tower cranes on construction sites. It helps an operator to anticipate the risk of contact between the moving parts of a tower crane and other tower cranes and structures. In the event that a collision becomes imminent, the system can send a command to the crane's control system, ordering it to slow down or stop. An anti-collision system can describe an isolated system installed on an individual tower crane. It can also describe a site wide coordinated system, installed on many tower cranes in close proximity.
History
Developments in tower crane design and the increasing complexity of construction sites in the 1970’s and 1980’s led to an increase in the quantity and proximity of tower cranes on construction sites. This increased the risk of collisions between cranes, particularly when their operating areas overlapped.
The first tower crane anti-collision systems were developed in France in 1985 by SMIE.
A Ministry of Labour directive issued in 1987 made anti-collision systems compulsory on all tower cranes in France.
In 2011, Hong Kong introduced a "Code of Practice for the Safe Use of Tower Cranes" and Singapore introduced a "Workplace Safety and Health construction Regulation". Both required the provision of an anti-collision system where more than one tower crane is in use.
In 2015, Luxembourg required automatic devices to be installed to avoid the risk of collision between tower cranes.
Collision avoidance with structures and other tower cranes
Various sensors are used to measure the position, velocity and angle of each tower crane’s moving parts. These sensors can be part of the anti-collision system or the crane. This information is sent via radio link to a computer and a display in the operator’s cabin. Several features commonly found across tower crane anti-collision systems use this data.
Zoning
Anti-collision systems allow prohibited zones to be defined. These are areas (such as schools, transport links, electrical power lines and areas beyond the site boundary) where the crane is not allowed to operate.
Situational awareness
The operator's cabin hosts a display showing the tower crane's position, movement and operating area. Where the tower crane’s operating area overlaps with other cranes or prohibited zones these are also displayed. The system alerts the operator when the crane is approaching a prohibited area or another crane.
Tower crane control
Anti-collision systems are often connected to the tower crane’s control system. This allows the anti-collision system to automatically slow down and stop the crane if there is a risk of an accident. The operator is then prevented from moving the crane towards the danger and can only move it away.
Supervisory system
A supervisory system is a typical feature of an anti-collision system that covers an entire construction site. It allows a site supervisor to have a complete view of tower crane operations on a construction site. It also allows for centralised configuration and maintenance of the system.
Fail-safe operation
If a fault occurs on a tower crane's anti-collision system, or it is bypassed, other tower cranes will be prevented from operating within the volume of the faulty system.
Collision avoidance with other vehicles
Anti-collision lights are required on tower cranes operating in or near to airfield flight paths. Three red flashing lights are positioned on each end and the top of the crane. They provide a visual warning to aircraft pilots.
Limitations
Tower crane anti-collision systems do not prevent collisions with mobile construction equipment such as mobile cranes and aerial work platforms.
Standards
A draft standard setting out the functional requirements of tower crane anti-collision devices and systems is open for comment. It is BS EN 17076. Anti-collision devices and systems for tower crane. Safety characteristics and requirements.
See also
Crane (machine) - Tower crane
Anti-collision light
References
Cranes (machines)
Construction | Tower crane anti-collision system | [
"Engineering"
] | 757 | [
"Construction",
"Engineering vehicles",
"Cranes (machines)"
] |
64,640,677 | https://en.wikipedia.org/wiki/Brexucabtagene%20autoleucel | Brexucabtagene autoleucel, sold under the brand name Tecartus, is a cell-based gene therapy medication for the treatment of mantle cell lymphoma (MCL) and acute lymphoblastic leukemia (ALL).
The most common side effects include serious infections, low blood cell counts and a weakened immune system. The most common side effects for the treatment of ALL include fever, CRS, hypotension, encephalopathy, tachycardias, nausea, chills, headache, fatigue, febrile neutropenia, diarrhea, musculoskeletal pain, hypoxia, rash, edema, tremor, infection with pathogen unspecified, constipation, decreased appetite, and vomiting.
Brexucabtagene autoleucel is a chimeric antigen receptor T cell therapy and is the first cell-based gene therapy approved by the U.S. Food and Drug Administration (FDA) for the treatment of mantle cell lymphoma.
Brexucabtagene autoleucel was approved for medical use in the United States in July 2020, and in the European Union in December 2020.
Medical uses
Brexucabtagene autoleucel is indicated for the treatment of adults with relapsed or refractory mantle cell lymphoma. It is also indicated for the treatment of adults with relapsed or refractory B-cell precursor acute lymphoblastic leukemia.
Mantle cell lymphoma (MCL) is a rare form of cancerous B-cell non-Hodgkin's lymphoma that usually occurs in middle-aged or older adults. In people with MCL, B-cells, a type of white blood cell which help the body fight infection, change into cancer cells that start to form tumors in the lymph nodes and quickly spread to other areas of the body.
Each dose of brexucabtagene autoleucel is a customized treatment created using the recipient's own immune system to help fight the lymphoma. The recipient's T cells, a type of white blood cell, are collected and genetically modified to include a new gene that facilitates the targeting and killing of the lymphoma cells. These modified T cells are then infused back into the recipient.
Adverse effects
The FDA label carries a boxed warning for cytokine release syndrome (CRS), which is a systemic response to the activation and proliferation of CAR-T cells causing high fever and flu-like symptoms, and for neurologic toxicities. Both cytokine release syndrome and neurologic toxicities can be fatal or life-threatening.
In April 2024, the FDA label boxed warning was expanded to include T cell malignancies.
The most common side effects of brexucabtagene autoleucel include serious infections, low blood cell counts and a weakened immune system. Side effects from treatment usually appear within the first one to two weeks after treatment, but some side effects may occur later. The most common Grade 3 or higher reactions were anemia, neutropenia, thrombocytopenia, hypotension, hypophosphatemia, encephalopathy, leukopenia, hypoxia, pyrexia, hyponatremia, hypertension, infection – pathogen unspecified, pneumonia, hypocalcemia, and lymphopenia.
Because of the risk of cytokine release syndrome and neurological toxicities, brexucabtagene autoleucel was approved with a risk evaluation and mitigation strategy (REMS), which includes elements to assure safe use. The risk mitigation measures for brexucabtagene autoleucel are identical to those of the REMS Program for another CAR-T therapy, axicabtagene ciloleucel (Yescarta).
History
Brexucabtagene autoleucel was approved for medical use in patients with MCL in the United States in July 2020, and in Europe in December 2020. It was later approved for patients with ALL in the US in October 2021 and Europe in December 2021.
Approval was based on ZUMA-2 (NCT02601313), an open-label, multicenter, single-arm trial of 74 participants with relapsed or refractory MCL who had previously received anthracycline- or bendamustine-containing chemotherapy, an anti-CD20 antibody, and a Bruton tyrosine kinase inhibitor. Participants received a single infusion of brexucabtagene autoleucel following completion of lymphodepleting chemotherapy. The primary efficacy outcome measure was objective response rate (ORR) per Lugano [2014] criteria as assessed by an independent review committee. The complete remission rate after treatment with brexucabtagene autoleucel was 62 percent, with an objective response rate of 87 percent.
The application for brexucabtagene autoleucel was approved under the accelerated approval pathway and it was granted priority review, breakthrough therapy, and orphan drug designations.
Efficacy for adults with relapsed or refractory B-cell precursor acute lymphoblastic leukemia was evaluated in ZUMA-3 (NCT02614066), a single-arm multicenter trial that evaluated brexucabtagene autoleucel, a CD19-directed chimeric antigen receptor (CAR) T-cell therapy. Participants received a single infusion of brexucabtagene autoleucel following completion of lymphodepleting chemotherapy.
Society and culture
Names
Brexucabtagene autoleucel is the international nonproprietary name.
References
Further reading
External links
Cancer treatments
Approved gene therapies
CAR T-cell therapy
Gilead Sciences
Orphan drugs | Brexucabtagene autoleucel | [
"Biology"
] | 1,232 | [
"Cell therapies",
"CAR T-cell therapy"
] |
64,640,872 | https://en.wikipedia.org/wiki/Boli%20%28fetish%29 | A boli (plural: boliw) is a fetish of the Bambara or Malinké of Mali.
Uses and customs
The boli can be zoomorphic (mostly a buffalo or a zebu) or even sometimes anthropomorphic. The populations of Mali who practice the so-called bamanaya cult, that is to say who indulge in the sacrifices of animals on the boliw and who communicate with the afterlife through masked dancers say they are Bamana.
In the Mandingo religions a boli is an object said "charged", that is to say that by its magic it is able to accomplish extraordinary things, such as to give death, predict the future, or take possession of someone. The boli, which can also be made up of human or animal placenta, clay, tissue, skin, etc., is itself the symbol of the placenta.
It is considered a living being and contains within it a core that can be either a stone, a metal or any other material. This nucleus or "grain" symbolizes the vital energy. The more blood the boli will receive, the more it will be "charged" with nyama (vital force).
Theft of konos
In his book “L'Afrique fantôme” (The Phantom Africa), the anthropologist Michel Leiris recounts his adventure in the center of Africa, from west to east, between 1931 and 1933. A dozen scientists under the leadership of Marcel Griaule make up this expedition named Dakar-Djibouti mission. Its objectives are ethnographic and linguistic and consist essentially of collecting, on behalf of the Trocadéro museum, objects of African culture before it is destroyed by colonialism. Leiris reveals in his notes the unethical methods used to appropriate the coveted objects. One of the episodes that became famous is the theft of konos. Using pressure, manipulation, blackmail and threat of retaliation from the colonial administration, offering ridiculous compensation and sometimes committing night thefts, the ethnologists seize several konos from some Bambara villages, under the frightened and amazed eyes of the population. These thefts turn out to be highly sacrilegious gestures in the eyes of the Bambaras and in Leiris’s own words, constitute a “booty” and an “enormity”. He qualifies himself and his team as “demons or particularly powerful and daring bastards”.
These konos will be successively exhibited at the Trocadéro museum, at the Museum of Mankind, at the Neuchâtel ethnography museum, among “one hundred masterpieces of the Museum of Mankind” in a New York museum as well as at the Quai Branly museum.
References
Bibliography
Graham Harvey, The Handbook of Contemporary Animism, 2014, p.233.
Bamana
African art
Magic (supernatural)
Religious objects
Traditional African medicine | Boli (fetish) | [
"Physics"
] | 594 | [
"Magic items",
"Religious objects",
"Physical objects",
"Matter"
] |
64,641,137 | https://en.wikipedia.org/wiki/Coverage%20%28information%20systems%29 | The Coverage of an Information system is a criterion for the completeness of the records in the information system.
It is defined as the ratio of the number of instances/records in the system (mostly implemented as a Database) that represent real world entities and the number of entities that exist (in the real world) and should be represented in the information system according to its purpose.
Example: If there are 170 countries in the world and an information system holds 153 country records then the coverage of countries of this information system is 90%.
Bibliography
https://www.phil-fak.uni-duesseldorf.de/fileadmin/Redaktion/Institute/Informationswissenschaft/stock/271.pdf
Information systems
Information | Coverage (information systems) | [
"Technology"
] | 153 | [
"Information systems",
"Information technology"
] |
64,642,219 | https://en.wikipedia.org/wiki/11%CE%B2-Chloromethylestradiol | 11β-Chloromethylestradiol (11β-CME2; developmental code name ORG-4333) is a synthetic steroidal estrogen which was never marketed. It has very high affinity for the estrogen receptor and dissociates from it relatively slowly. It was originally thought that 11β-CME2 might be a covalent ligand of the estrogen receptors, but its binding was subsequently shown to be fully reversible. The relative binding affinity of 11β-CME2 for the estrogen receptors ranges from 230 to 3,320% of that of estradiol depending on the study. 11β-CME2 also has about 14% of the relative binding affinity of estradiol for sex hormone-binding globulin (SHBG). The compound has been developed as a radiolabel for the ERs.
See also
11β-Methoxyestradiol
Moxestrol
References
Abandoned drugs
Secondary alcohols
Estranes
Organochlorides
Synthetic estrogens | 11β-Chloromethylestradiol | [
"Chemistry"
] | 215 | [
"Drug safety",
"Abandoned drugs"
] |
64,642,723 | https://en.wikipedia.org/wiki/Human%20City%20Interaction | Human-City Interaction is the intersection between human-computer interaction and urban computing. The area involves data-driven methods such as analysis tools, prediction methods to present the solutions to urban design problems. Practitioners, Designers, software engineers in this area employ large sets of user-centric data to design urban environments with high levels of interactivity. This discipline mainly focuses on the user perspective and devises various interaction design between the citizen (user) and various urban entities. Common examples in the discipline include the interactivity between human and buildings, Interaction between Human and IoT devices, participatory and collective urban design, and so on. The discipline attracts growing interests from people of various background such as designers, urban planners, computer scientists, and even architecture. Although the design canvas between human and city is board, Lee et al. proposed a framework considering the multi-disciplinary interests (Urban, Computers and Human) together, in which the emerging technologies such as extended reality (XR) can serve as a platform for such co-design purposes.
References
7 Woolliscroft and Polovina (2020) Improving healthcare through human city interaction - https://shura.shu.ac.uk/15786/1/Polovina%20Improving%20healthcare%20through%20human%20city%20interaction.pdf
Urban design
Information society
Human–computer interaction
Extended reality | Human City Interaction | [
"Technology",
"Engineering"
] | 288 | [
"Information society",
"Design stubs",
"Computing and society",
"Human–machine interaction",
"Computing stubs",
"Design",
"Human–computer interaction"
] |
64,642,851 | https://en.wikipedia.org/wiki/Oleg%20Grigoriyevich%20Kononenko | Oleg Grigoriyevich Kononenko (August 16, 1938 – September 8, 1980) was a member of Soviet cosmonaut group LII-1. He was born in the village of Samarskoye, in Rostov, Russia, then part of the Soviet Union. He graduated from Zhukovsky Air Force Institute in 1975. On July 12, 1977, he was selected for cosmonaut training as a pilot of the Buran space shuttle. He survived an aircraft ejection on the Soviet aircraft carrier Minsk on December 27, 1979.
Kononenko was married three times and had four children. He was killed on September 8, 1980, in the crash of a Yakovlev Yak-38 VTOL fighter on takeoff from the Minsk in the South China Sea.
Background
In 1958, he graduated as an instructor pilot at the Soviet Air Force academy in Saransk. In 1965, he also graduated as a test pilot at Zhukovskiy. Later, at the same academy, he became a helicopter pilot. In 1975, he graduated as a research pilot from the Moscow Aviation Institute. On July 12, 1977, Kononenko was selected as a member of one of the classes of cosmonauts who were due to carry out missions in the future on the space shuttle Buran, the first Russian reusable spacecraft, at the time under development. In 1979, he started his basic training for the position of cosmonaut. However, he maintained yet another degree, this time looking for the title of first class test driver. Kononenko was in the final stages of his cosmonaut tests when he was assigned to fly on a Yak-38 jet, taking off and landing vertically to perform some maneuvers over the China Sea as part of his training to obtain the first class test pilot title. On August 8, 1980, it took off with this aircraft from the aircraft carrier Minsk. However, moments after taking off, the plane failed in one of the engines and lost power, falling overboard before Kononenko had time to activate its ejector seat. The pilot died as soon as the plane hit the waters of the sea violently. The crew of the aircraft carrier from which he had taken off immediately managed to rescue his body. The ship then went to the city of Vladivostok, where Kononenko's body was left, and was later taken to Moscow, where he was buried with all honors. Kononenko posthumously received the Order of Lenin medal (his second), but he was never officially considered a cosmonaut, as he died just a few months from the completion of basic training, which would give him this title.
Less than two months after his death, another Soviet cosmonaut lost his life in a plane crash. This time, the victim was Leonid Ivanov, who died in an accident with a jet Mig-23. Exactly ten years and one day after Kononenko's death, another Soviet cosmonaut, Rimantas Stankyavichus, also died in an accident, during a performance at an air show, in Italy.
A few years after the accident, Russia selected another cosmonaut whose name, oddly enough, was also Oleg Kononenko. This one was called Oleg Dmitriyevich Kononenko. He participated in his first space mission together with the cosmonaut Sergei Volkov, having spent a season aboard the International Space Station. This was not even the first occasion when two namesake cosmonauts were chosen as such. Previously, a Russian cosmonaut named Aleksandr Aleksandrov and a cosmonaut from Bulgaria named Aleksandr Aleksandrov had previously gone up into space.
Bibliography
References
External links
1938 births
1980 deaths
People from Azovsky District
Soviet cosmonauts
Soviet Navy officers
Space program fatalities
Victims of aviation accidents or incidents in 1980
Victims of flight test accidents | Oleg Grigoriyevich Kononenko | [
"Engineering"
] | 782 | [
"Space program fatalities",
"Space programs"
] |
64,643,019 | https://en.wikipedia.org/wiki/Ralph%20N.%20Adams | Ralph Norman "Buzz" Adams (August 26, 1924 – November 28, 2002) was a distinguished bioanalytical chemist at the University of Kansas. The Adams Institute and Adams Professorship at the university are named after him.
Background and career
Adams was born in Atlantic City, New Jersey in 1924. He was drafted into the Army Air Corps in World War II, flying bombers in the Pacific theater. Upon his return, he studied chemistry at Rutgers University, graduating in 1950, followed by Ph.D. studies at Princeton University under N. Howell Furman. After 2 years on the faculty at Princeton, Adams became a professor at KU in 1955. Adams' research interests began studying solid electrodes and Electrochemical cell reactions. In later years, his research group changed direction and studied how electrical signaling in the brain underlie Neurological disorders such as Schizophrenia.
Awards
1996 - Oesper Award
1963 - Guggenheim Fellowship
1985 - Reilly Award
1982 - Higuchi Award for Basic Science
References
1924 births
Electrochemists
Rutgers University alumni
Princeton University
University of Kansas
2002 deaths
United States Army Air Forces bomber pilots of World War II | Ralph N. Adams | [
"Chemistry"
] | 222 | [
"Electrochemistry",
"Electrochemists"
] |
64,643,101 | https://en.wikipedia.org/wiki/Leonid%20Ivanov%20%28test%20pilot%29 | Leonid Grigoriyevich Ivanov (June 25, 1950 – October 24, 1980) was a member of Soviet Air Force Cosmonaut Training Group 6. He graduated from Higher Air Force School, Kachinsk, in 1971.
Ivanov was killed on 24 October 1980, in the crash of a MiG-27 aircraft during a test flight in Akhtubinsk, Astrakhan Oblast, Russian Soviet Federative Socialist Republic.
References
1950 births
1980 deaths
Soviet cosmonauts
Soviet test pilots
Space program fatalities
Victims of aviation accidents or incidents in 1980
Victims of aviation accidents or incidents in the Soviet Union
Victims of flight test accidents | Leonid Ivanov (test pilot) | [
"Engineering"
] | 128 | [
"Space program fatalities",
"Space programs"
] |
64,643,425 | https://en.wikipedia.org/wiki/Rosedale%20diet | The Rosedale diet is a low-carbohydrate fad diet based on the ideas of Ron Rosedale about how leptin affects the human body. The diet is marketed with questionable claims about how it can treat a large number of human health conditions.
The Rosedale diet is not based on sound science, and there is no evidence it is safe or effective.
Description
The Rosedale diet was devised by physician Ron Rosedale.
The diet falls into two parts, both of which have lists of restricted and permitted foods. A number of health supplements are recommended, as are 16 unconventional annual health checks. Generally, the diet severely restricts carbohydrate intake.
Reception
Harriet Hall has written that the book describing the diet is a "puerile effort" in comparison to Gary Taube's book Good Calories, Bad Calories which at least attempted to have a scientific basis.
The diet has been recommended by Joseph Mercola. Hall writes that "neither Mercola nor Rosedale can be recommended to anyone who is interested in science-based medicine".
See also
Atkins diet
Low-carbohydrate diet
References
Further reading
External links
Ron Rosedale's web site
American inventions
Brand name diet products
Diets
Fad diets
Low-carbohydrate diets | Rosedale diet | [
"Chemistry"
] | 264 | [
"Carbohydrates",
"Low-carbohydrate diets"
] |
64,643,632 | https://en.wikipedia.org/wiki/11%CE%B2-Methoxyestradiol | 11β-Methoxyestradiol (11β-MeOE2; developmental code name RU-2504) is a synthetic steroidal estrogen which was never marketed. It has about 86% of the relative binding affinity of estradiol for the estrogen receptor. 11β-MeOE2 is structurally related to moxestrol (11β-methoxy-17α-ethynylestradiol). 11β-MeOE2 and moxestrol are substantially more potent than their non-methoxylated analogues (estradiol and ethinylestradiol, respectively) in mice.
See also
Moxestrol
11β-Chloromethylestradiol
References
Abandoned drugs
Secondary alcohols
Estranes
Estrogen ethers
Synthetic estrogens | 11β-Methoxyestradiol | [
"Chemistry"
] | 170 | [
"Drug safety",
"Abandoned drugs"
] |
64,643,805 | https://en.wikipedia.org/wiki/Notholaena%20ferruginea | Notholaena ferruginea is a species name, which may refer to:
Notholaena trichomanoides, described in 1813 as Notholaena ferruginea (Desv.) Desv.
Myriopteris aurea, described in 1864 as Notholaena ferruginea (Willd. ex Link) Hook.
ferruginea | Notholaena ferruginea | [
"Biology"
] | 86 | [
"Set index articles on plants",
"Set index articles on organisms",
"Plants"
] |
64,644,342 | https://en.wikipedia.org/wiki/ITU-T%20Study%20Group%2016 | The ITU-T Study Group 16 (SG16) is a statutory group of the ITU Telecommunication Standardization Sector (ITU-T) concerned with multimedia coding, systems and applications, such as video coding standards. It is responsible for standardization of the "H.26x" line of video coding standards, the "T.8xx" line of image coding standards, and related technologies, as well as various collaborations with the World Health Organization, including on safe listening (H.870) accessibility of e-health (F.780.2), it is also the parent body of VCEG and various Focus Groups, such as the ITU-WHO Focus Group on Artificial Intelligence for Health and its AI for Health Framework.
Administratively, SG16 is a statutory meeting of the World Telecommunication Standardization Assembly (WTSA), which creates the ITU-T Study Groups and appoints their management teams. The secretariat is provided by the Telecommunication Standardization Bureau (under Director Seizo Onoe). WTSA instructed ITU to hold the Global Standards Symposium as a part of the deliberations that is open to the public.
The goal of SG16 is to produce Recommendations (international standards) for multimedia, including e.g. video coding, audio coding and image coding methods, such as H.264, H.265, H.266, and JPEG, as well as other types of multimedia related standards such as F.780.2, H.810, and H.870 on safe listening, together with the World Health Organization. It is also responsible for "the coordination of related studies across the various ITU-T SGs." Additionally, is also the lead study group on ubiquitous and Internet of Things (IoT) applications; telecommunication/ICT accessibility for persons with disabilities; intelligent transport system (ITS) communications; e-health; and Internet Protocol television (IPTV).
Trustworthy AI
Together with ITU-T Study Group 17 and AI for Good, the study group has been developing technology specifications under Trustworthy AI. Including items on homomorphic encryption, secure multi-party computation, and federated learning.
See also
ITU Telecommunication Standardization Sector
Joint Photographic Experts Group (JPEG)
Video Coding Experts Group (VCEG)
Moving Picture Experts Group (MPEG)
Thomas Wiegand
Gary Sullivan (engineer)
Video codec
Video compression
Video quality
References
External links
ITU main site
ITU-T Study Group 16 web site
structure of ITU-T Study Group 16
Official JPEG and JBIG web site
Official MPEG web site
International Telecommunication Union
Scientific organizations established in 1997
United Nations organizations based in Europe
ITU-T Study Groups
Multimedia | ITU-T Study Group 16 | [
"Technology"
] | 543 | [
"Multimedia"
] |
64,645,007 | https://en.wikipedia.org/wiki/Relationship%20between%20animal%20ethics%20and%20environmental%20ethics | The relationship between animal ethics and environmental ethics concerns the differing ethical consideration of individual nonhuman animals—particularly those living in spaces outside of direct human control—and conceptual entities such as species, populations and ecosystems. The intersection of these two fields is a prominent component of vegan discourse.
Overview
Generally, animal ethicists place the well-being and interests of sentient individuals at the center of their concern, while environmental ethicists focus on the preservation of biodiversity, populations, ecosystems, species and nature itself. Animal ethicists may also give value to these entities, but only so far as they are instrumentally valuable to sentient individuals.
Environmental ethicists consider it justifiable to remove or kill individual animals belonging to introduced species, who are consider to threaten the preservation of ecological entities, such as endangered and native species, which they consider to be more valuable than members of more common species. These actions are frequently opposed by animal ethicists, who may argue for a gradation of value of individual animals based on their level of sentience and would not consider whether an individual animal exists naturally as morally relevant; to them the individual's capacity to suffer is what matters.
Environmental ethicists may support hunting, which harms individual animals, in cases when it is considered to be ecologically beneficial. Some animal ethicists argue that we have a moral obligation to take steps to reduce wild animal suffering; this is something that environmental ethicists are normally against.
These differences of opinion have led some ethicists to argue that animal ethics and environmental ethics are incompatible, while others assert that the positions are reconcilable, or that the disagreements are not as strong as they first appear.
Perspectives
Animal ethicists
Animal rights philosopher Tom Regan, in his 1981 paper, conceived of an environmental ethic in which "nonconscious natural objects can have value in their own right, independently of human interests". In his 1982 book, The Case for Animal Rights, Regan argued that it is difficult to reconcile Aldo Leopold's holistic land ethic, where the "individual may be sacrificed for the greater biotic good", with the concept of animal rights and that, as a result, Leopold's view could justly be labelled as "environmental fascism".
The utilitarian philosopher Peter Singer, in Practical Ethics, argues for an environmental ethic which "fosters consideration for the interests of all sentient creatures, including subsequent generations stretching into the far future."
Eze Paez and Catia Faria assert that animal and environmental ethics "have incompatible criteria of moral considerability" and "incompatible normative implications regarding the interests of sentient individuals"; they also claim that environmental ethics fails to give a proper account of the problem of wild animal suffering. Oscar Horta has argued that contrary to first appearances, "biocentric views should strongly support intervention" to relieve the suffering of animals in the wild.
Environmental ethicists
J. Baird Callicott, in his 1980 paper "Animal Liberation: A Triangular Affair", was the first environmental philosopher to argue for "intractable practical differences" between the ethical foundations of Leopold's land ethic, taken as a paradigm for environmental ethics, with those of the animal liberation movement. Mark Sagoff made a similar case in his 1984 paper "Animal Liberation and Environmental Ethics: Bad Marriage, Quick Divorce", stating "[e]nvironmentalists cannot be animal liberationists. Animal liberationists cannot be environmentalists". In a follow-up paper, published in 1988, Callicott lamented the conflict that his earlier paper had sparked, stating "it would be far wiser to make common cause against a common enemy — the destructive forces at work ravaging the nonhuman world — than to continue squabbling among ourselves".
Michael Hutchins and Christin Wemmer in their 1986 paper "Wildlife Conservation and Animal Rights: Are They Compatible?", labelled the position of animal liberationists as "biologically illiterate and thus ill-equipped to provide an intelligent basis for wildlife conservation"; however, they conceded that "ethical philosophy faces a severe test when it comes to the conservation problem."
In a 1992 paper, Ned Hettinger raises the predation problem, in response to animal rights activists criticizing the environmental ethics of Holmes Rolston and his support of hunting, stating "[b]y arguing that humans should not join other predators and must not kill animals for basic needs, animal activists risk being committed to the view that all carnivorous predation is intrinsically evil".
Dale Jaimeson has argued that rather than being distinct positions, "animal liberation is an environmental ethic" and that it should be welcomed back by environmental ethicists.
Ricardo Rozzi has criticized animal ethicists for "taxonomic chauvinism" and has urged them to "reevaluate the participation of invertebrates in the moral community".
See also
Compassionate conservation
Intrinsic value
Opposition to hunting
Sentiocentrism
Speciesism
Welfare biology
Wildlife management
References
Further reading
Animal ethics
Environmental ethics | Relationship between animal ethics and environmental ethics | [
"Environmental_science"
] | 1,031 | [
"Environmental ethics"
] |
64,645,289 | https://en.wikipedia.org/wiki/Viedma%20ripening | Viedma ripening or attrition-enhanced deracemization is a chiral symmetry breaking phenomenon observed in solid/liquid mixtures of enantiomorphous (racemic conglomerate) crystals that are subjected to comminution. It can be classified in the wider area of spontaneous symmetry breaking phenomena observed in chemistry and physics.
It was discovered in 2005 by geologist Cristobal Viedma, who used glass beads and a magnetic stirrer to enable particle breakage of a racemic mixture of enantiomorphous sodium chlorate crystals in contact with their saturated solution in water. A sigmoidal (autocatalytic) increase in the solid-phase enantiomeric excess of the mixture was obtained, eventually leading to homochirality, i.e. the complete disappearance of one of the chiral species. Since the original discovery, Viedma ripening has been observed in a variety of intrinsically chiral organic compounds that exhibit conglomerate crystallization and are able to inter-convert in the liquid via racemization reactions. It is also regarded as a potential new technique to separate enantiomers of chiral molecules in the pharmaceutical and fine chemical industries (chiral resolution).
Mechanism
The exact interplay of the mechanisms leading to deracemization in Viedma ripening is a subject of ongoing scientific debate. It is, however, currently believed that for intrinsically chiral molecules, deracemization occurs via a combination of various phenomena:
Crystal growth and dissolution due to the particle-size dependence of solubility (i.e. Ostwald ripening)
Enantiospecific cluster aggregation to larger particles of the same chirality
Particle breakage
Racemization
Two key assumptions often invoked to explain the mechanism is that: a) small fragments generated by breakage for each enantiomeric crystal population can maintain their chirality, even when they are smaller than the critical radius for nucleation (and are thus expected to dissolve) and b) small chiral fragments can undergo enantiospecific aggregation to larger particles of the same chirality. Using these two assumptions, it can be shown mathematically, that any stochastic even immeasurable asymmetry of one enantiomeric crystal population over the other can be amplified to homochirality in a random manner.
Implications for the origin of life
In principle, molecules required for the generation of life, i.e. amino acids that combine to form proteins and sugars that form DNA molecules are all chiral and are thus able to adopt two mirror-image forms (often described as left- and right-handed), which from a chemical perspective are equally likely to exist. However, all biologically-relevant molecules known on earth are of a single handedness, even though their mirror images are also capable of forming similar molecules. The reason of the prevalence of homochirality in living organisms is currently unknown and is often connected to the origin of life itself. Whether homochirality emerged before or after life is currently unknown, but many researchers believe that homochirality could have been a result of amplification of extremely small chiral asymmetries.
Since Viedma ripening has been observed in biologically-relevant molecules, such as chiral amino acids it has been put forward by some as a possible contributing mechanism for chiral amplification in a prebiotic world.
See also
Crystallization
Racemic mixture
Chiral symmetry breaking
Racemization
Ostwald ripening
Solubility equilibrium
Chiral resolution
Enantioselective synthesis
Stereoselectivity
Spontaneous absolute asymmetric synthesis
References
Chirality
Racemic mixtures
Stereochemistry
Amino acids | Viedma ripening | [
"Physics",
"Chemistry",
"Biology"
] | 762 | [
"Biomolecules by chemical classification",
"Pharmacology",
"Racemic mixtures",
"Origin of life",
"Biochemistry",
"Stereochemistry",
"Chirality",
"Amino acids",
"Space",
"Chemical mixtures",
"nan",
"Asymmetry",
"Biological hypotheses",
"Spacetime",
"Symmetry"
] |
64,645,565 | https://en.wikipedia.org/wiki/N.%20Howell%20Furman | Nathaniel Howell Furman (1892–1965) was an American professor of analytical chemistry who helped develop the electrochemical uranium separation process as a member of the Manhattan Project.
Background and career
Furman was born in the Lawrenceville section of Lawrence Township, Mercer County, New Jersey in 1892. He attended Lawrenceville School, where he was a model student, graduating with a Master's Prize from his high school in 1909. He enrolled in Princeton University, where he received Phi Beta Kappa honors and graduated in 1913. He received an M.S. in 1915 and a Ph.D. from Princeton in 1917. Furman served in World War I in the Army Chemical Warfare Service. He returned to Princeton in 1919 to become an assistant professor, gaining promotion and tenure in 1937, and finished his career in 1960 as the Russell Wellman Moore professor of chemistry.
Manhattan Project
Furman helped develop an ether extraction process to extract Uranium oxide, a precursor to the fissile material used in the first atom bombs as discussed in the Smyth report. He served as a special consultant to the U.S. Atomic Energy Commission and was an advisor to the post-War Office of Scientific Research and Development. An August 8, 1945, special to the Princeton Bulletin revealed that multiple Princeton faculty, among them Albert Einstein, John Archibald Wheeler, Henry DeWolf Smyth, Hugh Stott Taylor, and Furman, had all "disappeared to Shangri-La" to work secretly on the bomb during wartime.
Books published
In 1933 Furman co-wrote Elementary Quantitative Analysis, one of the first textbooks in the field of analytical chemistry for undergraduates.
He co-wrote Analytical Chemistry of the Manhattan Project in 1950.
Personal life
A resident of Princeton, New Jersey, Furman owned a summer cottage in Charlotte, Vermont, on Lake Champlain and enjoyed sailboat racing and golf in his spare time. He had a son and a daughter—who became a chemist—with Hannah S. Hendrickson.
Honors
1953 - Palladium Medalist, Electrochemical Society
1951 - President of the American Chemical Society
1949 - Class of 1913 Distinguished Service Award
1948 - First recipient of the Fisher Award for analytical chemistry
1916-1917 - Charlotte Elizabeth Procter Fellowship
References
1892 births
1965 deaths
Lawrenceville School alumni
People from Charlotte, Vermont
People from Lawrence Township, Mercer County, New Jersey
Scientists from Princeton, New Jersey
Manhattan Project people
Electrochemists
Princeton University alumni | N. Howell Furman | [
"Chemistry"
] | 483 | [
"Electrochemistry",
"Electrochemists"
] |
64,646,501 | https://en.wikipedia.org/wiki/HAT-P-16 | HAT-P-16 is a F-type main-sequence star about 725 light-years away. The star has a concentration of heavy elements slightly higher than solar abundance, and low starspot activity. The survey in 2015 have failed to find any stellar companions to it.
The spectral analysis in 2014 have discovered the HAT-P-16 has a carbon to oxygen molar ratio of 0.58, close to Sun`s value of 0.55.
Planetary system
In 2010 a transiting hot superjovian planet was detected. Transit-timing variation analysis in 2016 have failed to detect an additional planets in the system.
In 2011 the observation utilizing a Rossiter–McLaughlin effect was performed, and the orbit of HAT-P-16b was found to be probably aligned with the equatorial plane of the star, misalignment angle equal to 10°.
The planet HAT-P-16b equilibrium temperature was found to be equal to 1567 K in 2013. The multiband photometry have failed to find any Rayleigh scattering in the HAT-P-16b atmosphere, which may indicate a presence of hazes or dense cloud deck.
References
Andromeda (constellation)
F-type main-sequence stars
Planetary systems with one confirmed planet
Planetary transit variables
J00381756+4227470 | HAT-P-16 | [
"Astronomy"
] | 267 | [
"Andromeda (constellation)",
"Constellations"
] |
64,646,818 | https://en.wikipedia.org/wiki/Genda%20Gu | Genda Gu is a condensed matter physicist at the Brookhaven National Laboratory. In his research, Gu specializes in the synthesis of large, high quality crystals for the production of superconductors. He works in the Brookhaven Laboratory's crystal growth lab, and as an adjunct professor at Stony Brook University. In 2012, Gu became a fellow of the American Physical Society.
Gu obtained his PhD from the Harbin Institute of Technology.
References
Condensed matter physicists
Fellows of the American Physical Society
Brookhaven National Laboratory staff
Year of birth missing (living people)
Living people | Genda Gu | [
"Physics",
"Materials_science"
] | 115 | [
"Condensed matter physicists",
"Condensed matter physics"
] |
64,647,211 | https://en.wikipedia.org/wiki/Abametapir | Abametapir, sold under the brand name Xeglyze, is a medication used for the treatment of head lice infestation in people six months of age and older.
The most common side effects include skin redness, rash, skin burning sensation, skin inflammation, vomiting, eye irritation, skin itching, and hair color changes.
Abametapir is a metalloproteinase inhibitor. Abametapir was approved for medical use in the United States in July 2020. The U.S. Food and Drug Administration (FDA) considers it to be a first-in-class medication.
Medical uses
Abametapir is indicated for the topical treatment of head lice infestation in people six months of age and older.
Contraindications
Abametapir has no contraindications according to the labeling.
Adverse effects
Common adverse effects are burning skin sensations (in 3% of patients), contact dermatitis (2%), skin redness (4%), rash (3%), and vomiting (2%).
Interactions
Abametapir blocks the liver enzymes CYP3A4, CYP2B6 and CYP1A2 in vitro. A single application of the drug may lead to increased blood concentrations of drugs that are metabolized by these enzymes.
Pharmacology
Mechanism of action
The drug inhibits enzymes called metalloproteinases. In lice, these enzymes play a role in egg development and survival; and consequently, blocking them will disrupt the lice's life cycle.
Pharmacokinetics
After application to the scalp, part of the substance reaches the bloodstream, where most of it (91.3–92.3%) is bound to plasma proteins. It is metabolized primarily by the liver enzyme CYP1A2 to abametapir hydroxyl and further to abametapir carboxyl (see structure drawings). Abametapir carboxyl has a plasma protein binding of 96.0–97.5% and is the predominant of the three substances in the circulation, having a Cmax 30 times and an area under the curve (AUC) 250 times that of abametapir itself.
The elimination half-life of abametapir is 21 hours. That of abametapir carboxyl is not well known; it is thought to be 71±40 hours or longer. It is not known whether the drug is eliminated via the urine or the faeces.
History
The U.S. Food and Drug Administration (FDA) approved abametapir based on evidence from two identical clinical trials of 699 participants with head lice. The trials were conducted at fourteen sites in the United States.
The benefit and side effects of abametapir were evaluated in two clinical trials that enrolled participants with head lice who were at least six months old.
About half of all enrolled participants was randomly assigned to abametapir and the other half to placebo. Abametapir lotion or placebo lotion were applied once as a ten-minute treatment to infested hair. The benefit of abametapir in comparison to placebo was assessed after 1, 7 and 14 days by comparing the counts of participants in each group who were free of live lice.
References
Further reading
External links
Antiparasitic agents
Lice | Abametapir | [
"Biology"
] | 695 | [
"Biocides",
"Antiparasitic agents"
] |
64,647,380 | https://en.wikipedia.org/wiki/Antonella%20Ferrara | Antonella Ferrara (born 1963) is an Italian control theorist and engineer, known for her work on sliding mode control.
Education and career
Ferrara is originally from Genoa, and studied electrical engineering at the University of Genoa, earning a laurea in 1987 and completing a Ph.D. in 1992. She became an assistant professor at the University of Genoa in 1992, and moved to the University of Pavia in 1998 as an associate professor. She was named professor of automatic control in 2005. At Pavia, she was originally affiliated with the department of computer engineering and systems science, and in 2011 became one of the founding members of a new department of electrical, computer, and biomedical engineering.
Ferrara chaired the Women in Control Committee of the IEEE Control Systems Society from 2013 to 2016.
Recognition
Ferrara was named an IEEE Fellow in 2020 "for contributions to sliding mode control theory". She is also a Fellow of the International Federation of Automatic Control.
Books
Ferrara is the coauthor of books including:
Freeway Traffic Modelling and Control (with Simona Sacone and Silvia Siri, Springer, 2018)
Advanced and Optimization Based Sliding Mode Control: Theory and Applications (with Gian Paolo Incremona and Michele Cucuzella, SIAM, 2019)
References
External links
1963 births
Living people
Engineers from Genoa
Control theorists
Italian women engineers
University of Genoa alumni
Academic staff of the University of Genoa
Academic staff of the University of Pavia
Fellows of the IEEE | Antonella Ferrara | [
"Engineering"
] | 288 | [
"Control engineering",
"Control theorists"
] |
64,647,451 | https://en.wikipedia.org/wiki/2020%20California%20Proposition%2014 | California Proposition 14 is a citizen-initiated ballot measure that appeared on the ballot in the 2020 California elections, for November 3, 2020. It authorizes state bonds to be issued worth $5.5 billion, which will fund the California Institute for Regenerative Medicine (CIRM), which serves as the state's center for stem cell research, and enable it to continue its operations. This measure passed with 51% of the vote.
Background
Robert N. Klein II, motivated by the suffering of family members from autoimmune diseases, launched a citizen initiative known as Proposition 71 in 2004, which created a state-funded center for stem cell research - the California Institute for Regenerative Medicine (CIRM). Based in San Francisco, the CIRM is responsible for with making grants and loans to stem cell research initiatives focused on developing treatment methods and completing research for clinical trials. Proposition 71 was approved by 59% of California voters and authorized $3 billion in bonds to fund the CIRM in addition to creating a Governing Board of 29 members as an Independent Citizens' Oversight Committee (ICOC). By 2020, $2.75 billion of the original $3 billion has been used or earmarked for funding of basic research, infrastructure, education, and clinical translational studies. For this reason, Klein spearheaded this initiative to authorize an additional $5.5 billion in bonds for the CIRM to support additional grants and operations under Proposition 14. Research areas of focus at CIRM include stem cell based research to mitigate or cure serious illness and chronic diseases such as cancer, heart disease, kidney disease, respiratory illnesses including COVID-19, diabetes, cancer, HIV/AIDs, paralysis, blindness, and more. A dedicated $1.5 billion under funding from Proposition 14 will be dedicated to research of diseases specific to the central nervous system and brain, including cancer, autism, dementia, Parkinson's and Alzheimers' disease.
Changes to the CIRM program and governance proposed in Proposition 14 include increased focus in improving patient access to stem cell treatments by expanding sites and facilities for human trials, the requirement for income earned from CIRM agreements to reduce the cost of stem cell treatments for patients, increase the ICOC from 29 members to 35 members, and to hire 15 full-time employees whose roles are dedicated to improving patient access to stem cell-derived therapeutics and treatments. Further, proposition 14 stipulates $1.5 billion to be spent researching brain and nervous system diseases, including dementia and Parkinson's disease. Estimated fiscal impact of Proposition 14 would include the initial $5.5 billion in bonds and $2.5 billion in interest, for an overall annual debt payment of $310 million over 25 years. Proposition 14 appropriates money from the general fund in order to fully pay the bond debt service.
Support
In addition to Klein, this measure is supported by the Regents of the University of California. It was also endorsed by governor Gavin Newsom and The Modesto Bee.
Proponents argue that biomedical research is crucial, particularly in light of the COVID-19 pandemic. Proponents of Proposition 14 have raised more than $13.4 million in campaign funds.
Opposition
As with Proposition 71, opposition to Proposition 14 includes many across the political spectrum including the Bakersfield Californian, California Nurses Association, California Catholic Conference, California Republican Party, Center for Genetics and Society, Friends Committee on Legislation of California, Green Party of California, Howard Jarvis Taxpayers Association, Libertarian Party of California, Los Angeles Times, Orange County Register, Peace and Freedom Party, Right to Life of Central California, San Bernardino Sun, San Francisco Chronicle, San Jose Mercury News, Scholl Institute of Bioethics, and CIRM board member Jeff Sheehy.
However, there was no significant organized opposition to Proposition 14, and the "No on Proposition 14" committee raised only $250.
References
2020 California ballot propositions
Stem cell research | 2020 California Proposition 14 | [
"Chemistry",
"Biology"
] | 795 | [
"Translational medicine",
"Tissue engineering",
"Stem cell research"
] |
64,647,989 | https://en.wikipedia.org/wiki/Binary%20Ninja | Binary Ninja is a reverse-engineering platform developed by Vector 35 Inc. It allows users to disassemble a binary file and visualize the disassembly in both linear and graph-based views. The software performs automated, in-depth code analysis, generating information that helps to analyze a binary. It lifts assembly instructions into intermediate languages, generating decompiled code.
Binary Ninja supports various CPU architectures and binary executable formats, and runs on Windows, macOS, and Linux. It also offers a free-to-use cloud version and a native commercial version.
History
Originally developed as an internal tool for a CTF team, the developers later formed Vector 35 Inc. to turn Binary Ninja into a commercial product. Development began in 2015, and the first public version was released in July 2016.
The commercial version was developed from scratch and does not share code with the original internal tool. The latter one is now open-sourced under the GPLv2 license.
Features and usage
User interface
Binary Ninja's user interface is, built using Qt, comprises several components such as a symbol list, a cross-reference window, and disassembly views (both linear and graph-based), a mini-graph, and a feature map. It also includes tools like a hex editor, strings listing, and a triage view.
Binary Ninja generates extensive annotations in the UI to assist binary analysis and also supports user-defined themes for customization.
API and plugins
Binary Ninja offers an API that can be accessed via Python, C++, or Rust. The API is open-sourced under the MIT License. It can interact with most of Binary Ninja's functionality, including the user interface, analysis tools, and intermediate languages (see below). It can be used to add support for new architectures or to automate tasks,
Plugins can be developed using the API to enhance Binary Ninja. Vector35 maintains a collection of official plugins, while the community has created numerous additional plugins.
Some notable plugins include the debugger, and the signature kit.
Binary Ninja Intermediate Languages (BNIL)
Binary Ninja offers three intermediate languages (ILs).
The low-level IL (LLIL) provides a detailed lifting of the underlying instructions from various architectures to a unified representation.
The medium-level IL (MLIL) creates variables with types and abstracts away the notion of the stack.
The high-level IL (HLIL, also known as the decompiler), offers a representation of the code that is similar to C source code.
Core analysis
Binary Ninja automatically performs various analyses on the binary. Some examples are:
function detection
cross-references for code and data
type inference
constant propagation
value-set analysis
jump table resolution
Binary editing and patching, shellcode compiler (SCC)
Binary Ninja offers binary patching and editing features. It can assemble an instruction at the current line, flip a conditional jump, etc. Edits and updated analysis are immediately reflected in the UI.
Binary Ninja can be used as a general binary editor. It supports several commonly-used transformations and encryption algorithms.
The shellcode compiler allows the user to compile and insert code via C syntax.
Supported architectures and executable file formats
Architectures
Binary Ninja supports the following CPU architectures officially:
x86 32-bit
x86 64-bit
ARMv7
Thumb2
ARMv8
PowerPC
MIPS
RISC-V
6502
nanoMIPS
TriCore
The support for these architectures vary and details can be found in the official FAQ.
Community-authored plugins add support for various other architectures.
Executable file formats
Binary Ninja supports the following executable file formats officially:
PE/COFF
ELF
Mach-O
.NES binary (via a plugin)
Raw binary
md1rom
See also
Ghidra
JEB
Radare2
Interactive Disassembler
Decompiler
Disassembler
References
Disassemblers | Binary Ninja | [
"Engineering"
] | 814 | [
"Reverse engineering",
"Disassemblers"
] |
77,751,417 | https://en.wikipedia.org/wiki/Ammonium%20hexafluoroindate | Ammonium hexafluoroindate is an inorganic chemical compound with the chemical formula .
Synthesis
The compound can be obtained by reacting ammonium fluoride and indium bromide in anhydrous methanol, or by reacting ammonium fluoride and indium fluoride in aqueous solution.
Also, a reaction involving indium hydroxide and ammonium fluoride:
Physical properties
The compound decomposes at 120–170 °C to obtain , and further decomposes to at 185–300 °C.
Ammonium hexafluoroindiate forms colorless crystals of tetragonal system, space group P4mnc, insoluble in water.
At 80 °C, a phase transition into the cubic phase occurs.
References
Fluoro complexes
Ammonium compounds
Fluorometallates
Hexafluorides | Ammonium hexafluoroindate | [
"Chemistry"
] | 175 | [
"Ammonium compounds",
"Salts"
] |
77,751,609 | https://en.wikipedia.org/wiki/Jan%20H.%20Spaas | Jan H. Spaas (born January 6, 1986, in Bilzen, Belgium) is a Belgian veterinarian and researcher in veterinary science.
Early life and education
Jan H. Spaas was born into a family with a strong background in equestrian activities.
Spaas pursued his high school education at Biotechnicum Bocholt and Sint-Augustinus Institute Bree, where he majored in Latin and Mathematics. He studied Veterinary Medicine at Ghent University, earning a bachelor's degree in 2007, followed by a master's degree in 2010. He completed his PhD in Veterinary Science in 2013 at the Department of Comparative Physiology and Biometrics, Faculty of Veterinary Medicine, Ghent University.
Career
In 2012, Jan Spaas co-founded Global Stem Cell Technology (GST) alongside his wife, veterinarian Sarah Broeckx. GST focused on developing regenerative therapies for musculoskeletal injuries in animals. The company quickly gained recognition, ranking among the top 10 global startups in animal health in 2018 and winning the Animal Pharm Award for Best Start-Up of the Year. Spaas also founded Pell Cell Medicals in 2013, which specialized in stem cell treatments for skin wounds in mammals. Both GST and Pell Cell Medicals were acquired by Boehringer Ingelheim in 2020, marking a significant milestone in Spaas' career. He raised €9.4 million for stem cell research, building a GMP production facility, and securing EU marketing authorization for two medicinal products developed under his leadership.
In 2020, Spaas was recognized as one of the top 30 entrepreneurs under 30 by Trends magazine and was appointed visiting professor at the Department of Morphology, Imaging, Orthopedics, Rehabilitation, and Nutrition at the Faculty of Veterinary Medicine, Ghent University. He has served as a promotor for several PhD students and is the inventor of 16 patent families encompassing over 40 patents. Spaas has also authored more than 40 peer-reviewed scientific publications and is an Associate Editor for Frontiers in Veterinary Science. In 2018, Spaas co-founded Via Nova Equine Hospital with veterinarian Marc Suls.
In 2022, Spaas was appointed Director of Global Innovation Development at Boehringer Ingelheim in Athens, Georgia, and later as Global Head of Research for Boehringer Ingelheim Animal Health in Germany in 2023.
In 2024, Spaas returned to Belgium, where he became chairman of the Board of Animab, a veterinary biotech company, and a board member of Intibio and Ventribio. He also serves as the managing director of Berkenbroek NV and Virtus Bonarum Cellarum BV. His current work includes leading research and development efforts in veterinary orthobiologics, animal feed supplements, and developing scientifically based food supplements.
Personal life
Jan Spaas is married to veterinarian Sarah Broeckx, with whom he has two daughters, Julie (born in 2016) and Charlotte (born in 2018). The family resides in Belgium, where Spaas manages his family estate, Berkenbroek NV, which spans nearly 200 hectares and has been in the family since 1897.
Publications
Spaas JH, Chiers K, Burvenich C, Van de Walle GR (2012). "The influence of lactation on equine mammary stem/progenitor cells." Stem Cells and Development, 21(16):3055-3067.
Broeckx S, Deprez P, Govaere J, Spaas JH, Christiaens J, Maes D (2011). Relationship between the housing of and physical health deficiencies in horses: a survey of horse owners and their perception. Vlaams Diergeneeskundig Tijdschrift, 80: 240–247.
References
1986 births
Living people
Belgian veterinarians
Ghent University alumni
Stem cell researchers
People from Bilzen | Jan H. Spaas | [
"Biology"
] | 817 | [
"Stem cell researchers",
"Stem cell research"
] |
77,752,004 | https://en.wikipedia.org/wiki/List%20of%20discrete%20and%20integrated%20graphics%20processing%20units | Graphics Processing Units (GPUs) are specialized electronic circuits designed to accelerate the processing of images, videos, and complex graphics tasks. They are essential components in various computing devices, ranging from personal computers to data centers. GPUs are broadly categorized into two types: Discrete GPUs and Integrated GPUs.
Discrete GPUs
Discrete GPUs are standalone graphics cards with their own dedicated memory, typically installed in a PCIe slot on a motherboard. They are primarily used in high-performance scenarios such as gaming, professional graphics work, and scientific computing. Discrete GPUs are known for their superior performance compared to integrated GPUs, as they do not share resources with the CPU.
Integrated GPUs
Integrated GPUs are built into the same chip as the CPU and share the system's memory. They are designed for more energy-efficient and cost-effective computing, making them suitable for everyday tasks such as web browsing, video playback, and light gaming. Integrated GPUs are commonly found in laptops, budget desktops, and mobile devices.
References
Graphics processing units
Lists of computer hardware | List of discrete and integrated graphics processing units | [
"Technology"
] | 218 | [
"Computing-related lists",
"Lists of computer hardware"
] |
77,753,239 | https://en.wikipedia.org/wiki/La%20Parguera%20Nature%20Reserve | La Parguera Nature Reserve (Spanish: Reserva Natural de la Parguera) is a protected area located in the southwestern Puerto Rico, primarily in the municipality of Lajas but also covering cays and islets under the municipal jurisdictions of Guánica and Cabo Rojo. The nature reserve is itself a unit of the Boquerón State Forest and it protects the Bahía Montalva mangrove forest in addition to mangrove bays, salt marshes and lagoons located along the coast of the Parguera barrio of Lajas, including its numerous cays and coral reefs. The reserve is mostly famous for its bioluminescent bay, locally called Bahía Fosforecente, (Spanish for 'phosphorescent bay'), one of the three of its kind in Puerto Rico and one of the seven year-round places where bioluminescent can be seen in the Caribbean.
Geography
The nature reserve is centered around La Parguera Bay, a large body of located immediately south of the town of Parguera (Poblado de Parguera). This body of water is surrounded by heavily forested bays, some of which include Puerto Quijano, Bahía Fosforecente, Bahía Monsio José, and Bahía Montalva. It also contains numerous cays and islets, such as Isla Mata la Gata, Cayo El Palo, Cayo San Cristóbal, Cayo Laurel, Cayo El Turrumote and Isla Mattei. The general area is bound to the north by the Sierra Bermeja and the Lajas Valley, and to the south by the Caribbean Sea.
Geology
The reserve is located in the Southern Puerto Rico karst region, characterized by reddish limestone. The area is also traversed by the recently discovered Punta Montalva fault, which was responsible for the 2019–20 Puerto Rico earthquakes.
Ecology
The environment of the nature reserve belongs to the Puerto Rican dry forest and Greater Antilles mangroves ecoregions. Administratively, La Parguera Nature Reserve is intended to protect an ecological corridor between the Boquerón and Guánica State Forests. The bay is also rich in coral reefs such as La Pared, a 20-mile-deep outcrop notable for its coral colonies and numerous fish and stingrays.
Fauna
Some of the most common animal species in the reserve include Adelaide's warbler (Setophaga adelaidae), brown pelicans (Pelecanus occidentalis), mangrove cuckoos (Coccyzus minor), Puerto Rican crescent sphaero (Sphaerodactylus nicholsi) and the Puerto Rican tody (Todus mexicanus). The protection of several endangered animal species such as manatees (Trichechus manatus), Cook's anole (Anolis cooki), the Puerto Rican nightjar (Antrostomus noctitherus) and the Yellow-shouldered blackbird (Agelaius xanthomus) was another reason for the official nature reserve designation.
Flora
Key plant species in the nature reserve include the almacigo (Bursera simaruba), bullet trees (Terminalia buceras), guayacan (Guaiacum sanctum), key thatch palms (Thrinax morisii), pink manjack (Tabebuia heterophylla), pipe organ cacti (Pilosocereus royenii), Turk's cap cacti (Melocactus intortus), and the endangered species guaiacwood (Guaiacum officinale), the sebucan (Leptocereus quadricostatus) and uña de gato (Pithecellobium unguis-cati). The area is also home to the extremely rare and critically endangered Psychilis krugii orchid.
History
There is evidence in and around Isla Mattei that the area was inhabited by the Taino by the time of the Spanish conquest of Puerto Rico. Due to the swampy and dense mangrove forest cover of the area, it remained undeveloped for most of its history. During the 18th-century the developed portions of the area formed part of sugarcane farms and haciendas, most notably Hacienda Fortuna and Finca Botoncillo. Corsican-Puerto Rican businessman Don Francisco Antonio Mattey was the owner and proprietor of these terrains, and the cay Isla Mattei is named after him. The salt marshes located immediately to the north and the northeast of the bioluminescent bay were further developed as salt evaporation ponds during the late 18th and early 19th-centuries.
The town of Parguera (Poblado de Parguera), also known as simply La Parguera, was first settled as a fishing village (villa pesquera) in 1825 as Villa Parguera (also the official name of the settlement), meaning 'red snapper village' after the prominence of Northern red snapper (Lutjanus campechanus) in the area. The local fishing industry however soon diminished due to overfishing and the economy quickly transitioned to tourism as the main local industry during the 20th-century. Tourism boomed with the establishment of Parador Villa Parguera by comedian and tourism businessman Henry LaFont during the 1960s. The quick development prompted the establishment of a zone of ecological protection, and, in 1972, the federal government established the Coastal Zone Management Law (Ley de Manejo de la Zona Costanera) included the area as a critical zone of protection. The Puerto Rico Department of Natural and Environmental Resources (DRNA) further established the Puerto Rico Coastal Zone Management Program (Programa de Manejo de la Zona Costanera de Puerto Rico) to mitigate the impact of tourism development in the coastal zones of the territory. The nature reserve was finally designated on September 20, 1979, making it the official fifth nature reserve in Puerto Rico after La Esperanza (1975), Punta Yeguas (1975), Punta Guaniquilla (1977) and La Cordillera Reef (1978).
Although tourism has proven to be the lifeline of the community it has brought negative impact onto the environment with the destruction of mangroves to build hotels, such as Parador Villa Parguera, and holiday residences, and the busy boating activity around the cays and reefs which at times has proven fatal to local animal communities such as manatees. Human activity has also proven disastrous for the bioluminescence in the area with Bahía Fosforecente now being the most endangered and least preserved out of the three bio bays in Puerto Rico.
See also
Boquerón State Forest
Puerto Mosquito
References
IUCN Category V
Bays of Puerto Rico
Bioluminescence
Cabo Rojo, Puerto Rico
Guánica, Puerto Rico
Lajas, Puerto Rico
Protected areas established in 1979
Protected areas of Puerto Rico
Tourist attractions in Puerto Rico
1979 establishments in Puerto Rico | La Parguera Nature Reserve | [
"Chemistry",
"Biology"
] | 1,425 | [
"Biochemistry",
"Luminescence",
"Bioluminescence"
] |
77,754,092 | https://en.wikipedia.org/wiki/Computer%20trainer | A computer trainer, sometimes known as a microprocessor trainer, is a type of small computer intended to introduce electronics and logic to new users. They were mostly used in the 1960s and 70s, although examples before and after that period can be found. They are very simple systems, similar to modern single board computers, but lack significant general-purpose capabilities. Trainers were often similar to electronics kits, especially during the early microprocessor era, compared to modern small computer systems like the Raspberry Pi which have significant use outside the training role.
An early example of a computer trainer is the 1955 Geniac, which the company referred to as an "electronic brain construction kit". Geniac consisted of a series of disks into which plugs were inserted to produce different circuit connections when the disks were rotated. Thus one could make a system where turning disk 1 to position 1 might light lamp 2. With enough work, the system could be used to produce a number of combinatorial logic operations that could be accessed with the right set of disk and switch positions. The system could be used to play Nim for instance. Examples using analog circuits were also common through the 1950s and 60s, essentially operating as electronic slide rules.
The expanding computer market in the early 1960s led to a second wave of trainers, this time dedicated to the task of introducing digital logic. An example is the Digital Equipment Corporation's (DEC) H-500 Computer Lab. This contained a number of logic elements for typical boolean logic operations like and , along with switches and wiring plugs. The user could connect the elements together to produce practical circuits like adders.
During the 1970s, the introduction of low-cost microprocessors led to a third major wave of trainers. Examples include the Motorola 6800-based Heathkit ET-3400 MicroComputer Learning System and the Radio Shack Science Fair Microcomputer Trainer Kit (a re-badged version of the Japanese FX-Micom R-165). During this period, trainers also took on a second role as prototyping systems to introduce new microprocessors to potential users. These systems tended to be more powerful and overlapped in concept with prototyping systems and single board computers. Examples include the KIM-1 and the OSI 300, both based on the MOS 6502. Practically every company had a similar system.
References
Educational hardware
History of computer science | Computer trainer | [
"Technology"
] | 493 | [
"History of computer science",
"Computing stubs",
"Computer science",
"History of computing"
] |
77,754,563 | https://en.wikipedia.org/wiki/Kluyveromyces%20nonfermentans | Kluyveromyces nonfermentans is a Kluyveromyces species occurring as a yeast. It was originally isolated from the deep sea, with various strains being isolated from sediment, a clam, and a crab. It is notable among the Kluyveromyces species as the only member unable to ferment glucose.
Discovery
In 1999, eleven strains of a previously unknown Kluyveromyces species were discovered in deep-sea samples from Suruga Bay and Sagami Bay off the coast of Honshu, Japan. The samples originated from marine sediment, a Calyptogena clam, and an unknown crab species.
Genomic analysis
At the time of discovery, K. nonfermentans was determined to be most closely related to Kluyveromyces aestuarii based on 18S rRNA gene sequences.
References
Saccharomycetaceae
Yeasts
Fungi of Japan
Fungi described in 1999 | Kluyveromyces nonfermentans | [
"Biology"
] | 196 | [
"Yeasts",
"Fungi"
] |
77,754,851 | https://en.wikipedia.org/wiki/CityLAB | cityLAB is a multidisciplinary research center within UCLA's Department of Architecture and Urban Design. Founded in 2006 by Dana Cuff and Roger Sherman, cityLAB leverages design, research, policy, and education to promote equitable and sustainable cities. cityLAB's work engages urban issues including affordable housing, equitable public space, and underrepresented narratives in Los Angeles and other cities.
Notable projects
Housing research and policy
cityLAB has developed proposals and policies that address the California affordable housing shortage, including co-authoring housing policy legislation.
One of cityLAB's longstanding research projects is addressing Los Angeles' housing shortage by building additional units in the backyards of single-family houses. cityLAB's research showed how outdated fire codes, setback requirements, and parking requirements could be adjusted to make such additional units, also called backyard homes or accessory dwelling units (ADUs), easier to permit. In 2015, cityLAB partnered with Kevin Daly Architects and UCLA architecture graduate students to build the BI(h)OME, a full-scale, prefabricated ADU prototype on UCLA’s campus. Based on their research into backyard homes, cityLAB co-authored AB 2299 (Bloom, 2016), which reduces restrictions on ADUs statewide and became state law in 2017. Working with the city of Los Angeles, cityLAB created a handbook guides homeowners in the process of building an ADU legally. 83,865 ADUs were permitted in California between 2016 and 2022.
In addition to backyard homes, cityLAB has identified other overlooked land that could be sites for affordable housing. Starting in 2018, they researched building affordable housing for teachers and other education staff on public land owned by schools, including K-12 public schools, community colleges, and public universities. Working with the Center for Cities + Schools at UC Berkeley, the Terner Center for Housing Innovation at UC Berkeley, and the Chan Zuckerberg Foundation, cityLAB found that every county in California has public school-owned land with the potential for education workforce housing. Based on this research, cityLAB co-authored AB 2295 (Bloom, 2022), which makes it easier for California school districts to build housing on their property, supporting efforts to attract and retain teachers. AB 2295 went into effect on January 1, 2024. cityLAB is working with school board members and district staff to train them in the process of planning and constructing affordable housing.
BruinHub
In 2019, cityLAB and UCLA’s Transportation Services found that 43% of students commuting to campus had one-way commutes of 60 minutes or more, and of those students, 42% had slept overnight on or near campus, sometimes in their cars, rather than commute home at night. To meet the needs of these housing-insecure and long-distance commuter students, cityLAB designed the BruinHub, a dedicated space in a former squash court in UCLA’s John Wooden Center which opened in 2021. The BruinHub provides study tables, charging stations, snacks, a microwave and refrigerator, as well as bean-shaped pods for naps, which were designed in partnership with Marta Nowak, a founder of the design studio AN.ONYMOUS. The project is a collaboration between cityLAB and UCLA Recreation, UCLA Student Affairs and the student organization Bruin Commuters. In winter quarter of 2024, a second BruinHub opened in the Strathmore Building on campus.
Public space work
With support from the UCLA Lewis Center for Regional Policy Studies, cityLAB studied intergenerational public space use in the Westlake neighborhood of Los Angeles in 2021. In 2022, they conducted a post-occupancy evaluation of Golden Age Park, a pocket park in the Westlake neighborhood, and organized a public celebration in the park. In partnership with the community organization Heart of Los Angeles and with support from the Institute of Transportation Studies, cityLAB has worked directly with youth to research how sidewalks impact their mobility and can support their independent travels.
Urban Humanities Initiative
In 2013, supported by funding from the Andrew W. Mellon Foundation, cityLAB launched the interdisciplinary Urban Humanities Initiative at UCLA, bringing together students and scholars from architecture, urban studies, and the humanities to study contemporary urban issues in the megacities of Mexico City, Tokyo, Shanghai and Los Angeles. UCLA’s Urban Humanities Initiative was a main sponsor of the inaugural Urban Humanities Network conference, which was held in Tucson, AZ in 2023.
Awards
The BI(h)OME, designed by Kevin Daly Architects based on cityLAB's research on backyard homes, received an AIA Small Project Award in 2018.
In 2019, cityLAB founder Dana Cuff received Architectural Record’s Women in Architecture Activist Award for her work at cityLAB. In 2020, she received recognition for cityLAB by receiving the ARCC James Haecker Award for Distinguished Leadership in Architectural Research, and in 2022, she received a UCLA Public Impact Research Award.
Local engagement
cityLAB has developed long-term partnerships with community organizations in Los Angeles, including the Los Angeles Public Library and Heart of Los Angeles. Reflections and Markings are two projects in partnership with these organizations that focus on telling immigrant histories in the neighborhood of Westlake, Los Angeles.
References
External links
cityLAB
UCLA Architecture and Urban Design
UCLA research institutes
Urban design
Urban planning | CityLAB | [
"Engineering"
] | 1,092 | [
"Urban planning",
"Architecture"
] |
77,755,356 | https://en.wikipedia.org/wiki/Bamboo%20in%20the%20Four%20Seasons | Bamboo in the Four Seasons is a late 15th century Japanese folding screen painting spanning six panels, attributed to Tosa Mitsunobu, but definitively within the Tosa school.
Depicting bamboo at different stages of growth throughout the seasons, the piece presents a transitory state, both of the plant, the seasons, as well as that of the evolution of the Tosa school and Muromachi period styles, which adapted the bamboo motif from previous Chinese paintings.
It is currently owned by the Metropolitan Museum of Art since 1975.
Description
Bamboo painting has been a common motif in Chinese painting from the Song and Yuan dynasty, depicted through paintings by Emperor Huizong in the 12th century.
One such prominent figure in bamboo painting was Li Kan, whose paintings gained prominence as he joined the Yuan Court, and as such wrote treatises on how to paint bamboo.
His style was passed on to his son Li Shixing (1283-1328). Within the first half of the 14th century, intellectual exchange between the Chinese Zen and the Japanese Zen schools intensified, which included the importation, followed by evolution of the painting style amongst the Muromachi elite.
The prominence of an independent style in Japan grew more prominent after the Heian period, with the emergence of Yamato-e, of which the Tosa school became renowned for, while maintaining infusion of ideas from China, a style known as kara-e. Bamboo in the Four Seasons is seen as an early-stage work by the Tosa School.
Japanese influences on Bamboo in the Four Seasons, depicts the transitory state of bamboo growth, from shoots to mature plant in the same space, from spring to winter, seen from right to left, the gold leaf backdrop conveying the concept of space. Impermanence and cycles is a prominent theme by showcasing the life cycle, adapted from Shinto and Buddhist precepts.
Over the course of centuries, the Tosa school's aesthetics would be studied and give way to Rinpa school in the Edo period.
Provenance
The time period of Bamboo in the Four Seasons is contemporary to that of the career of Tosa Mitsunobu (1434-1525), though it is uncertain if the painting is attributed to him, even though it was made by the Tosa School.
Efforts to construct the evolution and influences of Tosa school is only recent in scope.
The folding screen would have been a subject of study during the Azuchi–Momoyama and Edo period, thru open study by independent painters, machi-eshi (townsman painters). Observation and study would give way and influence towards Rinpa style, with prominent artists including Tawaraya Sōtatsu.
Owned previously by Yabumoto Shōgorō of Osaka, Bamboo in the Four Seasons would be acquired by art collector Harry G.C. Packard, who would then gift the painting to the MET in 1975. As of today, the panels are under designated accession number 1975.268.44,45.
Prominently rotated as part of MET's permanent collection, the painting has seen special exhibition at the Tokyo Metropolitan Teien Art Museum to commemorate the 500th anniversary of Osaka Castle from October-November 1986, as well as an exhibit at the Cleveland Museum of Art on 16th-century Japanese art in October-December 1991.
References
15th-century paintings
16th-century paintings
Bamboo
Byōbu
Gold ground paintings
Paintings in the Metropolitan Museum of Art
Works about seasons
Works about plants
Snow in art | Bamboo in the Four Seasons | [
"Biology"
] | 703 | [
"Works about plants",
"Plants"
] |
77,756,426 | https://en.wikipedia.org/wiki/Ammonium%20perbromate | Ammonium perbromate is an inorganic chemical compound with the formula . It shares similar properties to ammonium perchlorate, but is substantially more difficult to isolate, and has a complex mechanism of decomposition.
Properties
Ammonium perbromate is stable at room temperature, and has solubilities which are similar to ammonium perchlorate. Ammonium perbromate is much less hygroscopic in comparison to ammonium perchlorate, and has been shown to increase in weight when maintained in an atmosphere with high humidity.
Ammonium perbromate begins to decompose at a temperature between 170 and 180 Celsius, and has been observed to explode on occasion.
References
Ammonium compounds
Perbromates | Ammonium perbromate | [
"Chemistry"
] | 147 | [
"Ammonium compounds",
"Inorganic compounds",
"Inorganic compound stubs",
"Salts"
] |
77,756,684 | https://en.wikipedia.org/wiki/Taxonomic%20vandalism | Taxonomic vandalism is a term used in biology to describe the practice of publishing numerous scientifically unfounded or poorly-justified taxonomic names, often without adequate research or peer review. This phenomenon has been observed across various fields of taxonomy, but has been particularly prevalent in herpetology.
See also
Mihi itch
Taxonomic inflation
References
External links
Why Do Taxonomists Write the Meanest Obituaries?
Vandalism
Biological nomenclature
Biological classification | Taxonomic vandalism | [
"Biology"
] | 90 | [
"Biological nomenclature",
"Taxonomy (biology)",
"nan"
] |
77,757,125 | https://en.wikipedia.org/wiki/David%20Kipping | David Kipping is a British-American astronomer and associate professor at Columbia University, where he leads the Cool Worlds Lab. Kipping grew up in Warwickshire, he studied at Cambridge University and University College London, and completed a post-doctoral fellowship at Harvard University before joining Columbia University as an assistant professor in 2015. In 2016, Kipping launched the Cool Worlds YouTube channel to share his research topics with the wider public.
Along with Ingo Waldmann and Steve Fossey, Kipping discovered in 2009 that the exoplanet HD 80606b (previously known from radial velocity) transits its host star.
In 2011, Kipping founded the Hunt for Exomoons with Kepler, a project that searches for exomoons, natural satellites of exoplanets, using data collected by the Kepler space telescope.
In 2019, Kipping proposed a method of spaceflight known as the halo drive.
References
Exoplanetology
21st-century American astronomers
21st-century British astronomers
Columbia University faculty
Alumni of the University of Cambridge
Alumni of University College London
British emigrants to the United States
Living people
Year of birth missing (living people) | David Kipping | [
"Astronomy"
] | 231 | [
"Astronomers",
"Astronomer stubs",
"Astronomy stubs"
] |
77,758,560 | https://en.wikipedia.org/wiki/Ammonium%20hexafluoroniobate | Ammonium hexafluoroniobate is an inorganic chemical compound with the chemical formula .
Physical properties
Ammonium hexafluoroniobate forms white crystals of hexagonal system, space group R3m, insoluble in water.
It causes eye, skin, and respiratory tract irritation.
Uses
The compound is used as a solvent for organics.
References
Fluoro complexes
Niobates
Ammonium compounds
Fluorometallates
Hexafluorides | Ammonium hexafluoroniobate | [
"Chemistry"
] | 98 | [
"Ammonium compounds",
"Salts"
] |
77,760,323 | https://en.wikipedia.org/wiki/Ammonium%20hexafluorogallate | Ammonium hexafluorogallate is an inorganic chemical compound with the chemical formula .
Synthesis
A mechanochemical reaction between ammonium fluoride and gallium fluoride trihydrate (·) at a ratio of 3:1 produces the compound.
Also, a reaction of gallium(III) hydroxide, HF, and ammonium fluoride.
Physical properties
Ammonium hexafluorogallate occurs in two polymorphic forms: tetragonal at low temperature and cubic at high temperature, with both transforming reversibly.
Colorless crystals, soluble in water.
References
Fluoro complexes
Ammonium compounds
Fluorometallates
Hexafluorides | Ammonium hexafluorogallate | [
"Chemistry"
] | 145 | [
"Ammonium compounds",
"Salts"
] |
77,760,475 | https://en.wikipedia.org/wiki/Aberration-Corrected%20Transmission%20Electron%20Microscopy | Aberration-Corrected Transmission Electron Microscopy (AC-TEM) is the general term for using electron microscopes where electro optical components are introduced to reduce the aberrations that would otherwise reduce the resolution of images. Historically electron microscopes had quite severe aberrations, and until about the start of the 21st century the resolution was quite limited, at best able to image the atomic structure of materials so long as the atoms were far enough apart. Theoretical methods of correcting the aberrations existed for some time, but could not be implemented in practice. Around the turn of the century the electron optical components were coupled with computer control of the lenses and their alignment; this was the breakthrough which led to significant improvements both in resolution and the clarity of the images. As of 2024 correction of geometric aberrations is standard in many commercial electron microscopes. They are extensively used in many different areas of science.
History
Early Theoretical Work
Scherzer's theorem is a theorem in the field of electron microscopy. It states that there is a limit of resolution for electronic lenses because of unavoidable aberrations.
German physicist Otto Scherzer found in 1936 that the electromagnetic lenses, which are used in electron microscopes to focus the electron beam, entail unavoidable imaging errors. These aberrations are of spherical and chromatic nature, that is, the spherical aberration coefficient Cs and the chromatic aberration coefficient Cc are always positive.
Scherzer solved the system of Laplace equations for electromagnetic potentials assuming the following conditions:
electromagnetic fields are rotationally symmetric,
electromagnetic fields are static,
there are no space charges.
He showed that under these conditions the aberrations that emerge degrade the resolution of an electron microscope up to one hundred times the wavelength of the electron. He concluded that the aberrations cannot be fixed with a combination of rotationally symmetrical lenses.
In his original paper, Scherzer summarized: "Chromatic and spherical aberration are unavoidable errors of the space charge-free electron lens. In principle, distortion (strain and twist) and (all types of) coma can be eliminated. Due to the inevitability of spherical aberration, there is a practical, but not a fundamental, limit to the resolving power of the electron microscope."
The resolution limit provided by Scherzer's theorem can be overcome by breaking one of the above-mentioned three conditions. Giving up rotational symmetry in electronic lenses helps in correcting spherical aberrations. A correction of the chromatic aberration can be achieved with time-dependent, i.e. non-static, electromagnetic fields (for example in particle accelerators).
Prototypes
The benefit of the scanning transmission electron microscope (STEM) and its potentional for high-resolution imaging had been investigated by Albert Crewe. He investigated the need for a brighter electron source in the microscope, positing that cold field emission guns would be feasible. Through this and other iterations, Crewe was able to improve the resolution of the STEM from 30 Ångstroms (Å) down to 2.5 Å. Crewe's work made it possible to visualize individual atoms for the first time.
Crewe filed patents for electron aberration correctors, but could never get functioning prototypes.
In the early efforts to correct aberrations, low voltage electrostatic correctors were explored. These correctors used electrostatic lenses to manipulate the electron beam. The advantage of low voltage systems was their reduced chromatic aberration, as the energy spread of the electrons was lower at reduced voltages. Researchers found that by carefully designing these electrostatic elements, they could correct some of the spherical and chromatic aberrations that plagued early electron microscopes. These early correctors were crucial in understanding the behavior of electron optics and provided a stepping stone toward more sophisticated correction techniques.
Phase plate and similar ideas
The design parameters and functional requirements for phase plates were thoroughly examined in the context of their application as spherical aberration correctors. In particular, emphasis was placed on developing a programmable, electrostatic phase plate, highlighting its potential for precise control and adaptability in correcting aberrations.
First demonstrations
The first demonstration of aberration correction in TEM mode was demonstrated by Harald Rose and Maximilian Haider in 1998 using a hexapole corrector, and in STEM mode by Ondrej Krivanek and Niklas Dellby in 1999 using a quadrupole/octupole corrector. As the electron optic resolution improved, it became apparent that there also needed to be improvements to the mechanical stability of the microscopes to keep pace. Many aberration corrected microscopes heavily employ sound and temperature insulation, usually in an enclosure surrounding the microscope.
Early Commercial Products
Nion
Ondrej Krivanek and Niklas Dellby founded Nion in the late 1990s, initially as a collaboration with IBM. Their first products were correctors of spherical aberration correctors for existing STEMs. Later on, they designed an ACTEM from scratch, UltraSTEM 1.
CEOS
The approach to aberration correction used by Rose and Haider formed the basis of the company CEOS. They produced modular correctors which could be incorporated into microscopes produced by other vendors, which led to commercial products from FEI, JEOL, Hitachi, and Zeiss.
TEAM Project
The Transmission Electron Aberration-Corrected Microscope (TEAM) project was a collaborative effort between Lawrence Berkeley National Laboratory (LBNL), Argonne National Laboratory (ANL), Brookhaven National Laboratory, Oak Ridge National Laboratory, and the University of Illinois, Urbana-Chamaign with the technical goal of reaching spatial resolution 0.05 nanometers, smooth sample translation and tilt, while allowing for a variety of in-situ experiments.
The TEAM project resulted in several microscopes, the first was the ACAT at Argonne National Laboratory in Illinois which had the first chromatic aberration corrector, then the TEAM 0.5 and TEAM I at the Molecular Foundry in California, and concluded in 2009. Both the TEAM microscopes are S/TEMs (they can be used in both TEM mode and STEM mode) that correct for both spherical aberration and chromatic aberration. The TEAM microscopes are managed by the National Center for Electron Microscopy, a facility of the Molecular Foundry at LBNL, and ACAT by the Center for Nanoscale Materials at ANL.
Other
Several other aberration correctors have been designed and used in electron microscopes such as one by Takanayagi. Similar correctors have also been used at much lower energies such as for LEEM instruments.
Present State
In their modern state, resolutions of about 0.1 nm are fairly routine in microscopes around the world. This is true for both standard higher-voltage electron microscopes as well as a few ones specially designed to operate at lower electron energies. An important offshoot of the improved optical resolution is a companion improvement in the mechanical stability. Exploiting these improvements, significantly better identification of chemical contents of materials has become possible, as well as their atomic structure. This has had a major impact on our understanding across multiple fields of study.
Applications
There is a significant difference in the usage of AC-TEM across various fields. Despite aberration correction for electron microscopes existing in the case of STEMs, the amount of electrons needed to form useful images is far greater than biological samples can handle before being destroyed by radiation damage. Life science studies still heavily rely on conventional TEMs, which form a full image with their electron beam (similar to a conventional light microscope).
Physical Sciences
AC-TEM has been used extensively in physical sciences, in part due to the imperviousness of samples to radiation damage. This has ranged across chemistry, materials science and physics.
Life Sciences
Aberration correction have yet to be significantly used in the life sciences, due to generally low atomic weight contrast in biological systems and also the increased radiation damage. However, the side benefits such as improved mechanical stability and detectors have significantly improved data collection quality.
References
Crystallography
Electron microscopy | Aberration-Corrected Transmission Electron Microscopy | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 1,652 | [
"Electron",
"Electron microscopy",
"Materials science",
"Crystallography",
"Condensed matter physics",
"Microscopy"
] |
77,761,591 | https://en.wikipedia.org/wiki/Ammonium%20hexafluoroantimonate | Ammonium hexafluoroantimonate is an inorganic chemical compound with the chemical formula .
Synthesis
Also, a reaction of antimony pentafluoride and ammonium hexafluoromanganate:
Physical properties
It is soluble in water. It can form needle-shaped or columnar crystals.
Uses
The compound is used in fine chemistry and organic synthesis, for example as a catalyst, and can replace organic fluorides.
References
Fluoro complexes
Antimonates
Ammonium compounds
Fluorometallates
Hexafluorides | Ammonium hexafluoroantimonate | [
"Chemistry"
] | 112 | [
"Ammonium compounds",
"Salts"
] |
77,762,966 | https://en.wikipedia.org/wiki/Butylamphetamine | Butylamphetamine (code name PAL-90; also known as N-butylamphetamine or NBA) is a psychostimulant of the substituted amphetamine family which was never marketed.
It is the N-butyl analogue of amphetamine and is approximately 6-fold less potent than amphetamine in rats. The drug has been found to be inactive as a dopamine reuptake inhibitor or releasing agent ( and > 10,000nM, respectively). With regard to structure–activity relationships, the potency of N-substituted amphetamine derivatives decreases with increasing chain length in terms of both in vitro and in vivo activity.
The pharmacokinetics of butylamphetamine have been studied in humans. It can be metabolized by CYP2D6 via ring hydroxylation similarly to amphetamine. In addition, butylamphetamine can be N-dealkylated into amphetamine (6–9% excreted in urine after 24hours).
See also
Methamphetamine
Ethylamphetamine
Propylamphetamine
Isopropylamphetamine
References
Abandoned drugs
Butyl compounds
Norepinephrine-dopamine releasing agents
Prodrugs
Stimulants
Substituted amphetamines | Butylamphetamine | [
"Chemistry"
] | 271 | [
"Chemicals in medicine",
"Drug safety",
"Prodrugs",
"Abandoned drugs"
] |
62,393,372 | https://en.wikipedia.org/wiki/HElib | Homomorphic Encryption library or HElib is a free and open-source cross platform software developed by IBM that implements various forms of homomorphic encryption.
History
HElib was primarily developed by Shai Halevi and Victor Shoup, shortly after Craig Gentry was a researcher at IBM, with the initial release being on May 5, 2013.
Features
The library implements the Brakerski-Gentry-Vaikuntanathan (BGV) fully homomorphic encryption scheme, as well as optimizations such as Smart-Vercauteren ciphertext packing techniques.
HElib is written in C++ and uses the NTL mathematical library.
References
Homomorphic encryption
Cryptographic software
Free and open-source software
IBM software
Software using the Apache license
Free software programmed in C++ | HElib | [
"Mathematics"
] | 156 | [
"Cryptographic software",
"Mathematical software"
] |
62,394,573 | https://en.wikipedia.org/wiki/GRB%20190114C | GRB 190114C was an extreme gamma-ray burst explosion from a galaxy 4.5 billion light years away
(z=0.4245; magnitude=15.60est) near the Fornax constellation, that was initially detected in January 2019. The afterglow light emitted soon after the burst was found to be tera-electron volt radiation from inverse Compton emission, identified for the first time. According to the astronomers, "We observed a huge range of frequencies in the electromagnetic radiation afterglow of GRB 190114C. It is the most extensive to date for a gamma-ray burst." Also, according to other astronomers, "light detected from the object had the highest energy ever observed for a GRB: 1 Tera electron volt (TeV)—about one trillion times as much energy per photon as visible light"; another source stated, "the brightest light ever seen from Earth [to date]."
Significance
Recent publications following the event indicate that inverse Compton scattering is the mechanism responsible for producing TeV photons. X-ray photons are scattered off of the GRB's polar jets of electrons, which move at 0.9999c. In a scattering event, much of the energy of a relativistic electron is transferred to a photon. Researchers "have been trying to observe such very high energy emission from GRB's for a long time, so this detection is considered a milestone in high-energy astrophysics".
The most recent studies propose, in summary, a model of binary system of hypernova (BdHN I) with two neutron stars, where one of them collapses in a black hole, surrounded by an accretion disk and from whose poles the GRB is launched.
See also
GRB 020813
GRB 080916C
GRB 130427A
List of gamma-ray bursts
References
Further reading
External links
"GRB 190114C" – Hubble Space Telescope
"GRB 190114C" – University of Chicago/tevcat
20191119
Articles containing video clips
Delphinus
January 2019
190114C | GRB 190114C | [
"Astronomy"
] | 434 | [
"Delphinus",
"Constellations"
] |
62,395,197 | https://en.wikipedia.org/wiki/Independent%20safety%20officer | An independent safety officer (ISO) is a clinician or researcher who is independent of the clinical study team and helps to monitor a clinical trial for research participant (patient) safety, adverse events, trial progress, and data quality. An ISO has relevant experience with clinical trials as well as with the patient population and intervention being studied. Clinical trials using an ISO are usually smaller, single-site trials with a moderate to minimal risk intervention.
Need for an ISO
Safety surveillance of a clinical trial should be in proportion to the risk and complexity of the trial. Large, multi-site clinical trials are commonly overseen by a Data Monitoring Committee or Data and Safety Monitoring Board (DSMB) consisting of expert clinicians, biostatisticians, and ethicists or patient advocates. Small, minimal risk studies may be monitored by the principal investigator according to the data and safety monitoring plan (DSM plan) approved by the institutional review board (IRB).
For clinical trials with intermediate complexity or risk, the use of an ISO can be very helpful to monitor the trial for research participant safety, adherence to the protocol, and collection of good data. Examples of studies monitored by an ISO might include a trial involving Food and Drug Administration (FDA) approved drugs used in unapproved indications, non-significant risk medical devices, nutritional products used as a drug, research-only interventions such as an insulin clamp, or behavioral interventions with the possibility of psychological adverse events. Monitoring by an ISO may also be appropriate for higher risk single-site studies of short duration, such as pilot studies, for which convening a full DSMB is not feasible.
Job characteristics
An ISO is usually a physician or investigator with experience and training in both the disease and the intervention being studied. This allows the ISO to assess the safety of the research participants throughout the course of the trial. In addition, an ISO has experience with clinical trials so that they can monitor the progress of the trial for adequate enrollment, appropriate follow-up, adherence to protocol, and good data collection. Finally, the ISO is independent of the clinical trial they are monitoring. They are not a part of the study team and have no financial or scientific conflicts of interest with the clinical trial or the principal investigator.
Responsibilities
The DSM plan, which is approved by the IRB before a trial begins, will stipulate the use of an ISO for monitoring. In addition, the specific responsibilities of the ISO for that trial are defined by the ISO charter written by the principal investigator and the ISO. The charter typically sets out the aspects of the trial that will be reviewed, the frequency of data review and written reports, a plan for adverse event identification and reporting, a plan for monitoring of data quality and accuracy, and the criteria for decision-making regarding continuation, modification or termination of individual participants or the clinical trial.
An ISO meets regularly with the principal investigator and study team to review the progress of the trial. In these meetings, the ISO discusses: 1) a review of any adverse safety events; 2) protocol deviations and exclusions; 3) enrollment and follow-up of participants; 4) missing data and data quality controls; 5) any new medical advances that may require changes in the study protocol. The timing of the meetings depends on the risk to the participants as well as the degree of oversight needed for a particular trial.
If a clinical trial has regulatory lapses, excessive adverse events linked to the trial intervention, or fails to recruit adequate numbers of participants, the ISO may recommend that the clinical trial protocol be modified or the trial terminated.
Occasionally, additional expertise beyond the ISO is needed to accomplish a comprehensive review. With additional personnel, this is considered a Safety Committee. Most frequently a biostatistician will be the additional reviewer. Other additions can include a content expert for nonclinical issues, a methodology consultant, or another clinician that has additional specific expertise.
References
External links
Data and Safety Monitoring Board Training Manual for Investigator-Initiated Studies
Medical research
Research ethics
Clinical trials | Independent safety officer | [
"Technology"
] | 812 | [
"Research ethics",
"Ethics of science and technology"
] |
62,395,217 | https://en.wikipedia.org/wiki/Helopeltis%20antonii | Helopeltis antonii, also known as the tea mosquito bug, are heteropterans found within the Miridae family. They have a relatively large geographical distribution and are a known pest of many agricultural “cash” crops such as cocoa, cashew, and tea. Subsequently, their impact negatively influences economic growth within the regions in which they inhabit. Thus, their impact on humans has caused them to be of great interest biologically, resulting in significant environmental implications.
Distribution
Helopeltis antonii are found in a region known as the old-world tropics which encompasses places such as India, Northern Australia, Guinea, Vietnam, Tanzania, Nigeria, and Indonesia. More specifically, they are more concentrated in the agricultural regions of the old-world tropics. In India their distribution is primarily found within the “cashew belt” which is located along the western coast and central regions of the country due to its high affinity for these plants. However, different nations grow certain crops in various locations within their borders. Crops that H. antonii prefer will ultimately determine their specific distribution within a country.
Identification of distribution
H. antonii are often mistaken and misidentified with other Helopeltis species. Thus, identifying the exact geographical range of H. antonii has become a difficult process. However, recent advances in species identification though DNA barcoding has made it much easier. DNA barcoding is a rapid and relatively inexpensive identification technique that locates unique genetic markers in their DNA allowing for the accurate identification of not only H. antonii, but other species as well.
Mating
Reproduction for H. antonii occurs in 4 stages—arousal, mounting, copulation, and termination of copulation—and occurs year-round. Mounting, arousal, and termination of copulation occurs within a short time frame; copulation is much longer and more variable in length. Mating typically occur in shaded, covered areas
Arousal
Arousal consists of both chemical and tactile stimuli. Pheromones play an important role in the chemical attraction of females for mating. Although these chemical cues are important, physical cues comprise the bulk of mate attraction and arousal. Males are the sole initiators for reproductive encounters. This first done through sexual identification of a female partner. Sexual identification is only possible when in close proximity of each other. Once a female is located, the male makes contact with the female by gently probing her body with his antennae. Receptive females remain passive, permitting the male to proceed. In contrast, non-receptive females move to escape any further male interaction.
Mounting
Following the initial arousal, the process of mounting ensues. Males mount females on the posterior region of her body allowing the erect male rostrum to stroke the dorsal side of the female, just below the thoracic shield. This stroking behaviour quiets the female and allows for easier insertion of the male aedeagus into the female genital aperture. If insertion is not achieved the male begins a left to right stroking motion to aid in its insertion. Females can also kick or shake males off to prevent further progression of mating. When this occurs, males are quick to remount and re-attempt insertion of their aedeagus into the female genital aperture. Successful insertion leads to copulation.
Copulation
Once insertion has been established the male twists around in an end-to-end fashion to allow for copulation. Once in this end-to-end position, both the male and female remain still until copulation has completed. This can last anywhere from 10 minutes to 2 hours.
Termination of copulation
Following copulation, they abruptly disjoin, however, detachment can be often difficult due to the males' twisted position. Once separated both the male and female begin to feed and clean their own genitals and antenna—this feeding and cleaning behaviour typically occurs within a few steps from the site of copulation. Females do not respond to any other mating advances immediately following copulation. However, females typically reproduce more than once during their lifetime. Interspecific mating has been known to occur between Helopeltis species, specifically between H. antonii and H. theivora. However, their mating results in the production of unviable eggs. The production of eggs following interspecific mating between H. antonii and H. bradyi has not been observed. This ability and inability to engage in interspecific mating is due to the difference in genital structure between females. Females of both H. antonii and H. theivora have sclerotized rings that are not fused, whereas, the females of H. bradyi have fused sclerotized rings in its genitalia. This difference acts like a “lock and key” model for genitalia.
Oviposition
Males and females are able to reproduce and lay viable eggs after their first day of sexual maturity. Unmated females are capable of laying eggs; however, they are sterile. The sex ratio of males to females does not influence the number of eggs a female can lay but environments with a high ratio reduces female longevity due to mating exhaustion. Females that reproduce more than once lay a larger number of eggs during oviposition. Females probe plant tissues with the tip of their rostrum to find a suitable site for the deposition of their eggs. The exact reason behind site choice is unknown, but once found the female bends her abdomen to establish contact between her ovipositor and the plant tissue. The ovipositor is then inserted into the plant tissue and the eggs are deposited, below the epidermis and parenchymatous tissue of the plant, via abdominal contractions. The eggs are ovo-elongate and silvery-white in colour and are approximately 1.0x0.3mm in size. Abundance of eggs laid is also weather dependent. Conditions that yield higher temperatures and increased sun exposure result in a higher abundance; whereas cooler temperatures, less available sunlight, and increased rain exposure reduces abundance.
Development
H. antonii experiences partial metamorphosis, otherwise known as hemimetabolous development, which is characterized by it transition from an egg to nymph and eventually into a matured adult. This developmental pattern takes about 25 days from the time the eggs are laid to adulthood. The eggs take eggs 12–13 days to hatch followed by 12–13 days of progressive nymph instars. H. antonii experience 5 instars in total before reaching adulthood. During the first instar, the body appears light orange in colour and progresses to a deep orange in the second instar. During the third instar, the body beings to develop wing buds and a scutellar horn. Wing pads become visibly prominent as the fourth instar emerges. Finally, in the fifth instar, the wing pads cover half of the abdomen—with the wings being transparent—and the body is light brown in colour but darkens via sclerotization. Additionally, in the fifth instar, the dorsum of the thorax appears red in colour, the tergum of the abdomen a dull white, the dorsal abdominal segment a deep orange colour, and overlapped hemi-elytra covers over the abdomen with its distal end containing a triangular blackish-brown colouration.
The less-matured first, second and third instars tend to group close to each other and remain in proximity of their hatch site for feeding. In contrast, the more matured fourth and fifth instars tend to be more dispersed and feed in areas farther from their hatch site as a result. Matured females have a characteristic white patch present on their fifth abdominal segment.
Environmental influence
Although colouration is an important identifying feature of H. antonii it is subject to variation due to variations in temperature and sunlight exposure. Red colour morphs tend to peak in abundance during October and reach their minimum abundance during February (for males) and June (for females). Black colour morphs peak during June for both sexes. A brownish-black colour morph is also seen within the population, but its abundance is low, and its frequency remains constant throughout the year.
Diet and feeding
H. antonii are herbivorous insects that have been known to feed on more than 100 different plant species. The sites of feeding, on these plant hosts, are not localized. Rather, both adult and nymphs feed on various sites ranging from tender shoots, buds, stems, and even their fruiting bodies to obtain sap. H. antonii possess modified mouthparts which work to form a long straw-like structure known as a “stylet”. This modified mouth part enables them to suck up sap from deep within the plant tissues that would not otherwise be as easily accessible.
Seasonal Consumption
H. antonii feed on both native plants as well as agriculturally grown crops. However, their availability changes with the seasons. This change in availability is due to the different growth cycles host plants experience throughout the year. As host plants enter their fruiting or flushing stages, they begin to have a higher rates of sap production and as a result become targeted by H. antonii. In native, non-cultivated, habitats there appears to be a preference for certain types of host plants even when many others are present. During January to February Annona is preferred, from March to April neem is preferred, from May to August papaya is preferred, and from September to December Singapore cherry is preferred. In addition to the consumption of native plant species, agricultural “cash crops” such black pepper, cashew, cocoa, and tea as are often at high risk for consumption and damage due to their large-scale cultivation and ease of accessibility. However, their feeding schedule on these is agricultural crops are more restricted based due to growing and harvest seasons.
Plant preference
Like the seasonal preference of plants, preference is also seen in consumption habits of fruits with respect to different plants. For example, in custard apples the immature fruits are preferred over the matured fruits. Whereas in the Singapore cherries there is no observed feeding preference for immature or mature fruits.
Biological mechanics
Feeding requires the insertion of their stylet into the plant tissues. This insertion results in the secretion of saliva. Present within their saliva are toxic substances that cause death of plant tissues following feeding. However, the biochemical understanding of the toxin's toxicology and function within the saliva is poorly understood and is a site of current research.
Predators
Being a pest to many agricultural crops, resulting in severe destruction of plants following their consumption, have since made H. antonii a major target in hopes to reduce their prevalence in the agricultural industry. The use of insecticides and pesticides have long been used in an attempt to manage and reduce the damaging effects of H. antonii feeding. However, the effectiveness of these chemicals are concentration and volume dependent with respect to the type being used. Some of these pesticides have a prevalence of 500 liters per hectare at concentrations ranging from 50g/L-500g/L. The use of such chemical agents poses a risk not only to the environment but to humans as well—as exposure and administration levels continue to increase so too does its level of toxicity. Additionally, many countries that import these crops do not import those that have traces of pesticides. Thus, natural predators and parasitoids have been looked to for their biological control properties to prevent the use of these harmful chemicals.
Biological control
H. antonii are subject to both predation and parasitism via parasitoids. Parasitoids of both nymph and adult morphs include Hymenoptera (Braconidae, Platygastridae) and Diptera (Sarcophagidae). Predators are more extensive in diversity and consist of Hymenoptera (Formicidae, Vespidae), Coleoptera, Mantodea, and Odonata.
Of specific interest and use are hymenopteran parasitoids, specifically, Telenomus cupis due to their high specificity and specialization on H. antonii eggs. The employment of these parasitoid specialists has significantly decreased the abundance of H. antonii eggs to effectively reduce their devastating impact on agricultural crops. Additionally, these hymenopteran parasitoids are one of the few parasitoids that are active year-round.
The combined use of pesticides and biological control agents are less effective in reducing the number of H. antonii within agricultural systems. This is because these pesticides also act against biological control agents—reducing their effectiveness. Additionally, the biological control agents tend to be more affected by pesticides than H. antonii. Biological predators and parasitoids are more affected than H. antonii due to their increase locomotory abilities causing them to be exposed to larger amounts of the synthetic pesticides found on crops. The extensive and prolonged use of pesticides and its lesser effect on H. antonii, when compared to its biological control agents, raises concerns regarding pesticide resistance. However, such evidence has yet to suggest the acquisition of pesticide resistance in H. antonii.
Ecological and economic damage
H. antonii foraging behaviour, especially on commercially produced crops, has devastating impacts on overall crop yields showing yield reduction of as much as 35-75 percent. As more of the native landscape becomes converted into agricultural lands it provides an increased food supply for them. This increased food supply allows for an increase in population. As their population increases more plant tissues are subject to damage and injury. Thus, injured plants are no longer able to allocate their desired resources into fruit/seed production, rather, they are forced to allocate resources and energy into damage control and repair. This alternative allocation of resources is what causes the observed yield reductions. Poor yields result in poor economic outcomes for producers which also has adverse consequences for consumers such as increased prices, as well as an overall reduction in the number and overall quality of available products.
Foraging behaviour of H. antonii causes necrotic lesions to develop on plant tissues at feeding sites which can cause the death to new plant buds. Bud death inhibits plants from producing fruit—decreasing yield. Similarly, feeding on premature and mature fruits causes fruit desiccation resulting in a reduction in size and quality—as seen in cashew plants.
Fungal contribution
Although feeding results in necrotic lesioning and desiccation, it is not the only factor that impacts yield. Following foraging, fungal pathogens can enter the wound tissues more readily and cause die-back of shoots and is the primary cause of inflorescence blight. Even though fungal blight is a common occurrence in various plants, the wounds caused by H. antonii in plant tissues exacerbates and accelerates its effects. Die-back from blight also limits the plant's ability to produce products and grow—further perpetuating yield loss.
External links
http://www.yourarticlelibrary.com/zoology/helopeltis-antonii-distribution-life-cycle-and-control/24068
http://www.nbair.res.in/insectpests/Helopeltis-antonii.php
DropData cocoa pest guide
References
Bryocorinae
Pests (organism)
Hemiptera of Asia | Helopeltis antonii | [
"Biology"
] | 3,118 | [
"Pests (organism)"
] |
62,395,628 | https://en.wikipedia.org/wiki/Mycetome | A mycetome is a specialized organ in a variety of animal species which houses that animal's symbionts, isolating them from the animal's natural cellular defense mechanisms and allowing sustained controlled symbiotic growth. In several species, such as bed bugs and certain families of leech, these symbionts are attached to the gut and aid in the production of vitamin B from ingested meals of blood. In insects, the organisms that inhabit these structures are either bacteria or yeasts.
In bed bugs, it has been found that heat stress can cause damage to the mycetome, preventing the symbionts from being successfully passed from the adult female to her eggs at the time of oogenesis, causing the resulting nymphs to develop abnormally or to die prematurely.
References
Insect biology
Symbiosis
Animal anatomy | Mycetome | [
"Biology"
] | 176 | [
"Biological interactions",
"Behavior",
"Symbiosis"
] |
62,396,034 | https://en.wikipedia.org/wiki/CUX1 | CUX1 is an animal gene. The name stands for Cut like homeobox 1. The term "cut" derives from the "cut wing" phenotype observed in a mutant of Drosophila melanogaster. In mammals, a CCAAT-displacement activity was originally described in DNA binding assays. The human gene was identified following purification of the CCAAT-displacement protein (CDP) and has been successively been called CDP, Cut-like 1 (CUTL1), CDP/Cut and finally, CUX1. (Consequently, a literature search for CUX1 fails to bring up many of the earlier studies). Cut homeobox genes are present in all metazoans. In mammals, CUX1 is expressed ubiquitously in all tissues. A second gene, called CUX2, is expressed primarily in neuronal cells.
Reviews on CUX1
Multiple reviews have detailed the tissue-specific functions and genetic interactions in Drosophila and the early characterization of the CDP in mammalian cells, expression and activity of CUX1 in the myeloid cell lineage, multiple CUX1 isoforms, modes of DNA binding, early mouse models and cell-based assays, roles of CUX1 in kidney development and homeostasis, mechanisms by which CUX1 stimulates cell migration and invasion, roles of CUX1 and CUX2 in neurons of the cortex upper layer and the paradoxical implications of CUX1 in cancer. In addition, a number of commentaries present more specific views and speculations.
Genomic structure
The human CUX1 gene is large, encompassing more than 440,000 base pairs with two alternative first exons and an additional 23 exons. The last exon has a weak polyadenylation site allowing RNA polymerase II often to continue transcribing until it reaches an additional 10 exons. Splicing of this longer transcript from exon 14 to exon 25 generates a mature mRNA that codes for a protein that was called CASP (Cut alternatively spliced product). CASP localizes to the Golgi and does not seem to impact at all on CUX1 function. However, because of the complex structure of the gene, most oligos in microarrays were derived from the most 3' exons that are unique to CASP. Thus, until the advent of RNA sequencing CUX1 expression data has been essentially limited to immunohistochemical analyses. Similarly, many guide RNAs in CRISPR-Cas screening studies target the CASP-specific exons and do not affect CUX1.
CUX1 protein isoforms, evolutionarily conserved domains and functional regions
The use of two transcription start sites, alternative splicing of some exons and proteolytic processing combine to generate several CUX1 protein isoforms (reviewed) The full-length protein, often referred to as p200 CUX1, contains five evolutionarily conserved domains: a coiled-coil (CC), three Cut domains (C1, C2 and C3), originally called Cut repeats (CRs), and a Cut homeodomain (HD). The coiled-coil's function remains to be defined. The three Cut domains and the Cut homeodomain were originally characterized as DNA binding domains, and were later found to be involved also in protein-protein interactions. In addition to these conserved domains, the n-terminal 100 amino acids contains an autoinhibitory domain, while the carboxy-terminal region downstream of the homeodomain was shown to function as an active repression domain. In mid to late G1, the full-length protein is proteolytically processed to generate a shorter isoform, p110 CUX1 that lacks approximately the n-terminal 747 amino acids and thus contains only 3 DNA binding domains: CUT domains 2 and 3 and the Cut homeodomain (C2C3HD).
DNA binding assays with histidine-tagged fusion proteins showed that one Cut domain is not sufficient for DNA binding, while several combination of domains were found to bind to DNA with distinct affinities and kinetics: CR1CR2, CR3HD and CR2CR3HD. The C1C2 protein displayed very rapid "on" and "off" DNA binding rates, whereas any combination of a Cut domain with the Cut homeodomain exhibited slower binding kinetics. Interestingly, the full-length CUX1 protein purified from insect cells exhibited DNA binding kinetics similar to that of CR1CR2, suggesting that the Cut homeodomain may not be active in the context of the full-length protein.
Biochemical and cellular activities of p200 CUX1
p200 CUX1 is a very abundant protein that binds to DNA with extremely fast kinetics (rapid "on" and "off" rates). This is not consistent with a role as a classical transcription factor that binds stably to DNA and recruits a co-activator or a co-repressor, however, the p200 CUX1 protein may still be able to repress transcription by competition for binding site occupancy. Indeed, CUX1 was originally purified as the CCAAT-displacement protein (CDP). In addition to this potential role in transcriptional repression, recent studies revealed that p200 CUX1 functions as an auxiliary factor in base excision repair. In vitro, CUT domains of CUX1 stimulate the enzymatic activities of the 8-oxoguanine DNA glycosylase (OGG1) and the apurinic/apyrimidinic endonuclease 1 (APE1). In agreement with results from in vitro DNA repair assays, a p200 CUX1-GFP fusion protein is rapidly recruited to DNA damage generated by laser microirradiation, while CUX1 knockdown in human cells causes a delay in the repair of oxidative DNA damage and mono-alkylated bases in genomic DNA, and sensitizes cancer cells to treatments with H2O2, ionizing radiation and the mono-alkylating agent temozolomide. Conversely, p200 CUX1 overexpression increases the resistance of cancer cells to the same treatments. Structure/function analysis established that a fusion protein containing Cut domains 1 and 2 linked to a nuclear localization signal (C1C2-NLS) is rapidly recruited to DNA damage and is sufficient to accelerate the repair oxidative DNA damage and mono-alkylated bases in genomic DNA. Since the C1C2-NLS protein is devoid of transcription activation potential, these results suggest that Cut domains are directly involved in DNA repair.
Transcriptional and cellular activities of p110 CUX1
The shorter p110 CUX1 isoform stably interacts with DNA and can function as transcriptional repressor or activator depending on promoter context. Transcription and cell-based assays demonstrated a role for p110 CUX1 in stimulating cell cycle progression and cell proliferation, strengthening of the spindle assembly checkpoint, ensuring an efficient DNA damage response, promoting cell migration and invasion, and increasing resistance to apoptotic signals. Of note, the p200 CUX1 protein was inactive in all these transcriptional and cell-based assays.
p110 CUX1 has been demonstrated to bind the protective allele of FTO single nucleotide polymorphisms (SNPs) rs8050136 or rs1421085 highly associated with human obesity, and promote the expression of RPGRIP1L. RPGRIP1L hypomorphism in mice results in obesity, suggesting an important role of CUX1 in body weight regulation.
CUX1 overexpression in human cancers
CUX1 is overexpressed in many cancers. The comprehensive molecular characterization of human colon and rectal cancer performed by The Cancer Genome Atlas (TCGA) ranked CUX1 as the fifth gene on a scale showing a correlation between tumour aggressiveness and gene expression/somatic copy number alterations. TCGA and REMBRANDT data also show shorter survival of glioblastoma patients with high CUX1 mRNA expression (reviewed). In smaller scale studies, immunohistochemical analyses on breast, pancreas and glioblastoma cancers reveal that CUX1 expression inversely correlates with relapse-free and overall survival. An alternative CUX1 transcript that is initiated within intron 20 and codes for a p75 isoform is expressed specifically in the testis and thymus. This transcript was found to be aberrantly expressed in many breast tumour cells lines and breast tumours. Transgenic mice expressing this transcript in mammary epithelial cells were shown to develop mammary tumours with metastasis to the lung.
Tumors in CUX1 transgenic mice
CUX1 transgenic mice develop tumors in multiple organs and tissues after a long latency period. Transgenic mice expressing either p75, p110 or p200 CUX1 in mammary epithelial cells develop mammary tumours with a low penetrance (~20%) and with a long latency period. Metastasis to the lung was observed in three cases of mammary tumors expressing p75 CUX1.
The mechanisms of action differ widely between p110 CUX1 and p200 CUX1. Transgenic mice expressing p110 CUX1 in mammary epithelial cells develop mammary tumors that exhibit a sub-tetraploid chromosome number, suggesting passage through tetraploidy resulting from cytokinesis failure. Cells do not usually survive as tetraploid with multiple centrosomes. Overexpression of p110 CUX1 was shown to activate a transcriptional program that reinforces the spindle assembly checkpoint and delays mitosis until extranumerary centrosomes have clustered to two poles, thereby enabling bipolar mitosis and survival of tetraploid cells. Yet, passage through a multipolar intermediate enriches for merotelic chromosome attachments, leading to chromosome mis-segregation and the rapid generation of aneuploid populations from which tumorigenic cells emerge.
Tumors that develop in p200 CUX1 transgenic mice reveal a different mode of action, as 44% of these tumors harboured a spontaneous mutation activating the Kras gene. The cooperation between RAS and p200 CUX1 was confirmed by lentiviral infections in the lung. RAS oncogenes do not transform primary cells, but instead cause cellular senescence. This results from the elevated production of reactive oxygen species (ROS) that lead to oxidative DNA damage. Biochemical and cell-based assays demonstrated that the CUT domains within CUX1 and other Cut domain proteins stimulate the enzymatic activities of some enzymes of the base excision repair pathway and accelerate the repair of oxidative DNA damage. Hence, human and primary rodent fibroblasts that are transfected with KRAS and CUX1 exhibit similar ROS levels as cells that receive only KRAS but show much reduced DNA damage. In agreement with these findings, CUX1 knockdown is synthetic lethal in all cancer cells exhibiting high levels of ROS as a consequence of activating mutations in either KRAS, HRAS, BRAF or EGFR.
Genetic studies defining CUX1 as a haploinsufficient tumor suppressor
Loss-of-heterozygosity (LOH) of the 7q22.1 chromosomal region, where CUX1 resides, was reported in 8–22% of various cancer, and in close to 50% in therapy-associated leukemias. As no inactivating mutations were found in the remaining allele, the notion that CUX1 could be the tumor suppressor gene on 7q22.1 was dismissed for some time. However, refined mapping in leiomyomas and myeloid leukemias eventually pointed to CUX1 as the sole tumor suppressor gene in this region. These genetic data suggest that CUX1 may be a haploinsufficient tumor suppressor gene. In addition to LOH events, large scale DNA sequencing identified inactivating point mutations in 1–5% of cancers where both alleles are present. There is no tumor case where both CUX1 allele are inactivated.
What is the tumor suppressor function of CUX1?
While the biochemical activities of CUX1 that explain its role in tumor maintenance and progression have been well defined, the biochemical functions of CUX1 involved in tumor suppression have yet to be firmly established. Two mechanisms have been proposed.
One study reported that CUX1 functions as a transcriptional activator of PIK3IP1, a gene that codes for the phosphoinositide-3-kinase interacting protein 1 (PIK3IP1), a direct inhibitor of the PI3K p110 catalytic subunit. CUX1 knockdown caused a decrease in PIK3IP1 expression that was associated with an increase in PI3K signaling and AKT signaling. A separate study, however, argued that CUX1 is itself a target of AKT signaling. Activation of the PI3K–AKT signaling pathway by insulin-like growth factor 1 (IGF1) or by AKT2 overexpression led to the upregulation of CUX1 and was associated with resistance to apoptosis, whereas treatment of cells with the PI3K inhibitor LY294002 decreased CUX1 expression and increased apoptosis. Whether the discrepancies in the results and conclusions from these two studies can be explained by differences in cell-types or other reasons remains to be verified.
The auxiliary role of CUX1 in base excision repair has raised the possibility that its tumor suppressor function may be linked to its function in DNA repair. CUX1 knockdown delays DNA repair in multiple cell lines. Mouse embryo fibroblasts (MEFs) derived from a Cux1-/- knockout mouse exhibit increased genomic instability23, moreover Cux1+/−- heterozygous MEFs are haploinsufficient for DNA repair18. Yet, whether CUX1 hemizygosity augments the risk of cancer by increasing the frequency of mutations and/or genomic rearrangements remains to be formally tested.
References
Developmental genes and proteins
Gene clusters
Evolutionary developmental biology | CUX1 | [
"Biology"
] | 3,007 | [
"Induced stem cells",
"Developmental genes and proteins"
] |
62,396,576 | https://en.wikipedia.org/wiki/Hypergraph%20removal%20lemma | In graph theory, the hypergraph removal lemma states that when a hypergraph contains few copies of a given sub-hypergraph, then all of the copies can be eliminated by removing a small number of hyperedges. It is a generalization of the graph removal lemma. The special case in which the graph is a tetrahedron is known as the tetrahedron removal lemma. It was first proved by Nagle, Rödl, Schacht and Skokan and, independently, by Gowers.
The hypergraph removal lemma can be used to prove results such as Szemerédi's theorem and the multi-dimensional Szemerédi theorem.
Statement
Let be -uniform (every edge connects exactly r vertices) hypergraph with vertices. The hypergraph removal lemma states that for any exists such that for any -uniform, -vertices hypergraph with fewer than subhypergraphs isomorphic to it is possible to remove all copies of by removing at most edges.
An equivalent formulation is that, for any hypergraph with copies of , we can eliminate all copies of from by removing hyperedges.
Graph removal lemma is a special case with .
Proof idea of the hypergraph removal lemma
The high level idea of the proof is similar to that of graph removal lemma. We prove a hypergraph version of Szemerédi's regularity lemma (partition hypergraphs into pseudorandom blocks) and a counting lemma (estimate the number of hypergraphs in an appropriate pseudorandom block). The key difficulty in the proof is to define the correct notion of hypergraph regularity. There were multiple attempts to define "partition" and "pseudorandom (regular) blocks" in a hypergraph, but none of them are able to give a strong counting lemma. The first correct definition of Szemerédi's regularity lemma for general hypergraphs is given by Rödl et al.
In Szemerédi's regularity lemma, the partitions are performed on vertices (1-hyperedge) to regulate edges (2-hyperedge). However, for , if we simply regulate -hyperedges using only 1-hyperedge, we will lose information of all -hyperedges in the middle where , and fail to find a counting lemma. The correct version has to partition -hyperedges in order to regulate -hyperedges. To gain more control of the -hyperedges, we can go a level deeper and partition on -hyperedges to regulate them, etc. In the end, we will reach a complex structure of regulating hyperedges.
Proof idea for 3-uniform hypergraphs
For example, we demonstrate an informal 3-hypergraph version of Szemerédi's regularity lemma, first given by Frankl and Rödl. Consider a partition of edges such that for most triples there are a lot of triangles on top of We say that is "pseudorandom" in the sense that for all subgraphs with not too few triangles on top of we have
where denotes the proportion of -uniform hyperedge in among all triangles on top of .
We then subsequently define a regular partition as a partition in which the triples of parts that are not regular constitute at most an fraction of all triples of parts in the partition.
In addition to this, we need to further regularize via a partition of the vertex set. As a result, we have the total data of hypergraph regularity as follows:
a partition of into graphs such that sits pseudorandomly on top;
a partition of such that the graphs in (1) are extremely pseudorandom (in a fashion resembling Szemerédi's regularity lemma).
After proving the hypergraph regularity lemma, we can prove a hypergraph counting lemma. The rest of proof proceeds similarly to that of Graph removal lemma.
Proof of Szemerédi's theorem
Let be the size of the largest subset of that does not contain a length arithmetic progression. Szemerédi's theorem states that, for any constant . The high level idea of the proof is that, we construct a hypergraph from a subset without any length arithmetic progression, then use graph removal lemma to show that this graph cannot have too many hyperedges, which in turn shows that the original subset cannot be too big.
Let be a subset that does not contain any length arithmetic progression. Let be a large enough integer. We can think of as a subset of . Clearly, if doesn't have length arithmetic progression in , it also doesn't have length arithmetic progression in .
We will construct a -partite -uniform hypergraph from with parts , all of which are element vertex sets indexed by . For each , we add a hyperedge among vertices if and only if Let be the complete -partite -uniform hypergraph. If contains an isomorphic copy of with vertices , then for any . However, note that is a length arithmetic progression with common difference . Since has no length arithmetic progression, it must be the case that , so .
Thus, for each hyperedge , we can find a unique copy of that this edge lies in by finding . The number of copies of in equals . Therefore, by the hypergraph removal lemma, we can remove edges to eliminate all copies of in . Since every hyperedge of is in a unique copy of , to eliminate all copies of in , we need to remove at least edges. Thus, .
The number of hyperedges in is , which concludes that .
This method usually does not give a good quantitative bound, since the hidden constants in hypergraph removal lemma involves the inverse Ackermann function. For a better quantitive bound, Leng, Sah, and Sawhney proved that for some constant depending on . It is the best bound for so far.
Applications
The hypergraph removal lemma is used to prove the multidimensional Szemerédi theorem by J. Solymosi. The statement is that any for any finite subset of , any and any large enough, any subset of of size at least contains a subset of the form , that is, a dilated and translated copy of . Corners theorem is a special case when .
It is also used to prove the polynomial Szemerédi theorem, the finite field Szemerédi theorem and the finite abelian group Szemerédi theorem.
See also
Graph removal lemma
Szemerédi's theorem
Problems involving arithmetic progressions
References
Hypergraphs
Graph theory | Hypergraph removal lemma | [
"Mathematics"
] | 1,338 | [
"Theorems in graph theory",
"Theorems in discrete mathematics"
] |
62,396,988 | https://en.wikipedia.org/wiki/X17%20particle | The X17 particle (X17 boson) is a hypothetical subatomic particle proposed by Attila Krasznahorkay and his colleagues to explain certain anomalous measurement results; these anomalous measurements are known as ATOMKI anomaly or beryllium (8Be) anomaly or X17 anomaly. The particle has been proposed to explain wide angles observed in the trajectory paths of particles produced during a nuclear transition of beryllium-8 nuclei and in helium nuclei. The X17 particle could be the force carrier for a postulated fifth force, possibly connected with dark matter, and has been described as a protophobic (i.e., ignoring protons) vector boson with a mass near .
History
In 2015, Krasznahorkay and his colleagues at ATOMKI, the Hungarian Institute for Nuclear Research, posited the existence of a new, light boson with a mass of about (i.e., 34 times heavier than the electron). In an effort to find a dark photon, the team fired protons at thin targets of lithium-7, which created beryllium-8 nuclei in an excited state, which then decayed to the ground state and produced pairs of electrons and positrons. Excess decays were observed at an opening angle of 140° between the and particles and a combined energy of approximately . This indicated that a small fraction of the excited beryllium-8 might shed its excess energy in the form of a new particle. The result was successfully repeated by the team.
Feng et al. (2016) proposed that a "protophobic" X boson, with a mass of , suppressed couplings to protons relative to neutrons and electrons at femtometre range, could explain the data. The force may explain the − 2 muon anomaly and provide a dark matter candidate. , several research experiments are underway to attempt to validate or refute these results.
Krasznahorkay (2019) posted a preprint announcing that he and his team at ATOMKI had successfully observed the same anomalies in the decay of stable helium atoms as had been observed in beryllium-8, strengthening the case for the existence of the X17 particle.
This was covered in science journalism, focusing largely on the implications that the existence of the X17 particle and a corresponding fifth force would have in the search for dark matter.
In 2021 the workshop "Shedding light on X17" was held at Centro Enrico Fermi in Rome, Italy. The workshop discussed the ATOMKI anomaly and its theoretical interpretation and future experiments to confirm and explain it. One of the experiments that plans to repeat the original ATOMKI lithium–beryllium experiment is MEG II at PSI institute; the measurement was planned (in 2021) to be completed in 2022. Also Universite de Montreal's 6 MV (6 megavolt) Tandem Van de Graaff Facility in Montreal has an experiment that attempts to reproduce the ATOMKI measurement; data taking should take place in early 2023.
In 2022, another preprint was published by Krasznahorkay et al. supporting the X17 particle hypothesis.
CERN's NA64 experiment and NA62 experiment have reported in 2021 and 2023 respectively results of conducted searches that have put stringent limits for the existence of the X17 particle.
In early 2023 the MEG II experiment performed its replication of the ATOMKI lithium–beryllium experiment; as of January 2024 the results have not yet been published (although the measurements were made in early 2023). As of September 2024, the analysis of measurement results has been done but an article has not been published.
Skepticism
, the ATOMKI paper describing the particle has not been peer reviewed and should therefore be considered preliminary. In late 2019, a follow-up paper was published in Acta Physica Polonica B. Efforts by CERN and other groups to independently detect the particle have been unsuccessful so far.
The ATOMKI group had claimed to find various other new particles earlier in 2016 but abandoned these claims later, without an explanation of what caused the spurious signals. The group has also been accused of cherry-picking results that support new particles while discarding null results.
The X17 particle is not consistent with the Standard Model, so its existence would need to be explained by another theory.
See also
Axion
List of particles
750 GeV diphoton excess
References
Bosons
Dark matter
Hypothetical elementary particles
Force carriers | X17 particle | [
"Physics",
"Astronomy"
] | 918 | [
"Dark matter",
"Matter",
"Physical phenomena",
"Unsolved problems in astronomy",
"Concepts in astronomy",
"Force carriers",
"Unsolved problems in physics",
"Bosons",
"Fundamental interactions",
"Exotic matter",
"Hypothetical elementary particles",
"Physics beyond the Standard Model",
"Subato... |
62,398,551 | https://en.wikipedia.org/wiki/International%20Society%20for%20Sexual%20Medicine | The International Society for Sexual Medicine (ISSM) is a medical society devoted to the study of the medicine of human sexuality. It publishes two journals, The Journal of Sexual Medicine, and the open-access Sexual Medicine Reviews. It was founded in 1978 and was formerly known as the ISIR/ISSIR.
References
Medical associations
Sexuality
Medical and health organisations based in the Netherlands | International Society for Sexual Medicine | [
"Biology"
] | 76 | [
"Behavior",
"Sexuality",
"Sex"
] |
62,398,563 | https://en.wikipedia.org/wiki/Sexual%20Medicine%20Reviews | Sexual Medicine Reviews is an open access peer-reviewed journal of the medicine of sexuality. It is abstracted and indexed by Scopus.
References
Sexology journals
Elsevier academic journals
Open access journals | Sexual Medicine Reviews | [
"Biology"
] | 40 | [
"Behavior",
"Sexuality stubs",
"Sexuality"
] |
62,398,615 | https://en.wikipedia.org/wiki/OpenFHE | OpenFHE is an open-source cross platform software library that provides implementations of fully homomorphic encryption schemes. OpenFHE is a successor of PALISADE and incorporates selected design features of HElib, HEAAN, and FHEW libraries.
History
PALISADE
Development began with the OpenFHE precursor PALISADE (software).
PALISADE adopted the open modular design principles of the predecessor SIPHER software library from the DARPA PROCEED program.
SIPHER development began in 2010, with a focus on modular open design principles to support rapid application deployment over multiple FHE schemes and hardware accelerator back-ends, including on mobile, FPGA and CPU-based computing systems.
PALISADE began building from earlier SIPHER designs in 2014, with an open-source release in 2017 and substantial improvements every subsequent 6 months. Much of the development was done at Raytheon BBN and NJIT.
PALISADE development was funded originally by the DARPA PROCEED and SafeWare programs, with subsequent improvements funded by additional DARPA programs, IARPA, the NSA, NIH, ONR, the United States Navy, the Sloan Foundation and commercial entities such as Duality Technologies. PALISADE has subsequently been used in commercial offerings, such as by Duality Technologies who raised funding in a Seed round and a later Series A round led by Intel Capital.
OpenFHE
PALISADE authors along with selected authors of HElib, HEAAN, and FHEW libraries released a new library in July 2022.
The initial release of the library included all features of PALISADE v1.11 and added several new design features, such as Hardware Acceleration Layer for multiple hardware acceleration backends and new bootstrapping procedures.
OpenFHE is used as an FHE backend for the Google Transpiler project.
Features
OpenFHE includes the following features:
Post-quantum public-key encryption
Fully homomorphic encryption (FHE)
Brakerski/Fan-Vercauteren (BFV) scheme for integer arithmetic with approximate bootstrapping and RNS optimizations
Brakerski-Gentry-Vaikuntanathan (BGV) scheme for integer arithmetic with RNS optimizations
Cheon-Kim-Kim-Song (CKKS) scheme for real-number arithmetic with RNS optimizations
Ducas-Micciancio (FHEW) scheme for Boolean circuit evaluation with optimizations
Chillotti-Gama-Georgieva-Izabachene (TFHE) scheme for Boolean circuit evaluation with extensions
Multiparty extensions of FHE
Threshold FHE for BGV, BFV, and CKKS schemes
Proxy re-encryption for BGV, BFV, and CKKS schemes
References
External links
Official Website
Homomorphic encryption
Cryptographic software
Free and open-source software
Software using the BSD license | OpenFHE | [
"Mathematics"
] | 578 | [
"Cryptographic software",
"Mathematical software"
] |
62,400,348 | https://en.wikipedia.org/wiki/Huawei%20Honor%206 | The Honor 6 and Honor 6 Plus are the mid-range Android smartphones produced by Huawei. It was released in August 2014.
It is the second mid-range phone series of Huawei's sub-brand Honor. Honor 6 has a 5.0-inch in-plane switching liquid crystal display and runs on Android 6.0, paired with EMUI 3.1 after latest update, while Honor 6 Plus has a 5.5-inch display and bigger size dimensions.
Honor 6 is the second phone by Honor which uses HiSilicon Kirin 920 chipset, while the Honor 6 Plus uses Kirin 925.
Specifications
The 2 phones has 3 GB of random access memory, 16 or 32 gigabytes of internal storage and is connectable using Bluetooth 4.0, Wifi 802.11 a/b/g/n and 2G/3G/4G LTE.
It also has global positioning system function. Honor 6 has a 13 MP rear camera with autofocus, and 5 MP front camera. However, the Honor 6 Plus has a 8 MP rear camera with autofocus, paired with 2 MP depth sensor and a 8 MP front camera.
Source
https://www.gsmarena.com/honor_6-6461.php
Android (operating system) devices
Mobile phones introduced in 2014
Honor 6
Discontinued smartphones
Mobile phones with infrared transmitter
Huawei Honor | Huawei Honor 6 | [
"Technology"
] | 290 | [
"Discontinued flagship smartphones",
"Flagship smartphones"
] |
62,400,361 | https://en.wikipedia.org/wiki/Huawei%20Honor%203X | The Honor 3X is an Android midrange smartphone produced by Honor, a sub brand of Huawei. It was released in December 2013.
Honor 3X comes with Android 4.2 out of box and runs on Android 4.4 KitKat OS after latest update.
Specifications
Saying about storage, the phone has 2 GB RAM, and has 8GB or 16GB of internal storage. It is connectable using Bluetooth and Wi-Fi. On the display side, it features a 5.5-inch 720x1280 pixels LCD display.It also features Mediatek MT6592 processor.This phone is now discontinued.
References
Android (operating system) devices
Mobile phones introduced in 2013
Honor 3X
Huawei Honor
Discontinued smartphones | Huawei Honor 3X | [
"Technology"
] | 151 | [
"Crossover devices",
"Phablets"
] |
62,401,003 | https://en.wikipedia.org/wiki/Cell%20cycle%20regulated%20Methyltransferase | CcrM (or M.CcrMI) is an orphan DNA methyltransferase, that is involved in controlling gene expression in most Alphaproteobacteria. This enzyme modifies DNA by catalyzing the transference of a methyl group from the S-adenosyl-L methionine substrate to the N6 position of an adenine base in the sequence 5'-GANTC-3' with high specificity. In some lineages such as SAR11, the homologous enzymes possess 5'-GAWTC-3' specificity. In Caulobacter crescentus Ccrm is produced at the end of the replication cycle when Ccrm recognition sites are hemimethylated, rapidly methylating the DNA. CcrM is essential in other Alphaproteobacteria but its role is not yet determined. CcrM is a highly specific methyltransferase with a novel DNA recognition mechanism.
CcrM role in cell cycle regulation
Methylations are epigenetic modification that, in eukaryotes, regulates processes as cell differentiation, and embryogenesis, while in prokaryotes can have a role in self recognition, protecting the DNA from being cleaved by the restriction endonuclease system, or for gene regulation. The first function is controlled by the restriction methylation system while the second by Orphan MTases as Dam and CcrM.
CcrM role have been characterized in the marine model organism Caulobacter crescentus, which is suitable for the study of cell cycle and epigenetics as it asymmetrically divides generating different progeny, a stalked and a swarmer cell, with different phenotypes and gene regulation. The swarmer cell has a single flagellum and polar pili and is characterized by its mobility, while the stacked cell has a stalk and is fixed to the substrate. The stacked cell enters immediately in S-phase, while the swarmer cell stays in G1-phase and will differentiate to a stacked cell before entering the S-phase again.
The stacked cell in S phase will replicate its DNA in a semiconservative manner producing two hemimethylated DNA double strands that will be rapidly methylated by the Methyltransferase CcrM, which is only produced at the end of the S phase. The enzyme will methylate more than 4 thousand 5'-GANTC-3' sites in around 20 minutes, and then it will be degraded by the LON protease. This fast methylation plays an important role in the transcriptional control of several genes and controls the cell differentiation. CcrM expression is regulated by the CtrA master regulator, and in addition various 5'-GANTC-3' sites methylation sites regulate CcrM expression, which will only occur at the end of the S phase when this sites are hemimethylated. In this process CtrA regulates the expression of CcrM and more than 1000 genes in the pre-divisional state, and SciP prevents the activation of CcrM transcription in non replicative cells.
CcrM role in Alphaproteobacteria
Orphan MTases are common in bacteria and archea CcrM is found in almost every group of Alphaproteobacteria, excepting in Rickettsiales and Magnetococcales, and homologs can be found in Campylobacterota and Gammaproteobacteria. Alphaproteobacteria are organisms with different life stages from free living to substrate associated, some of them are intracellular pathogens of plants, animal and even human, in those groups the CcrMs must have an important role in cell cycle progression.
CcrM miss regulation have shown to produce severe miss control of cell cycle regulation and differentiation in various Alphaproteobacteria; C. crescentus , the plant symbiont Sinorhizobium meliloti and in the human pathogen Brucella abortus. Also CcrM gene has proven to be essential for the viability of various Alphaproteobacteria.
Structure and DNA recognition mechanism
CcrM is a type II DNA Methyltransferase, that transfer a methyl group from the methyl donor SAM to the N6 of an adenine in a 5'-GANTC-3' recognition sites of hemimethylated DNA. Based on the order of the conserved motifs that form the SAM binding, the active site and the target recognition domain in the sequence of CcrM it can be classified as a β-class adenine N6 Methyltransferase. CcrM homologs in Alphaproteobacteria have an 80 residues C terminal domain, with non well characterized function.
CcrM is characterized by a high degree of sequence discrimination, showing a very high specificity for GANTC sites over AANTC sites , being able to recognize and methylate this sequence in both double and single strand DNA. CcrM in complex with a dsDNA structure was resolved, showing that the enzyme presents a novel DNA interaction mechanism, opening a bubble in the DNA recognition site (The concerted mechanism of Methyltransferases relies in the flip of the target base), the enzyme interacts with DNA forming an homodimer with differential monomer interactions.
CcrM is a highly efficient enzyme capable of methylating a high number of 5'-GANTC-3' sites in low time, however if the enzyme is processive (the enzyme binds to the DNA and methylate several methylation sites before dissociation) or distributive (the enzyme dissociates from DNA after each methylation) it is still in discussion. First reports indicated the second case, however more recent characterisation of CcrM indicate that it is a processive enzyme.
References
DNA
Gene expression
Alphaproteobacteria | Cell cycle regulated Methyltransferase | [
"Chemistry",
"Biology"
] | 1,184 | [
"Gene expression",
"Molecular genetics",
"Cellular processes",
"Molecular biology",
"Biochemistry"
] |
62,401,268 | https://en.wikipedia.org/wiki/Cubic%20fathom | A cubic fathom or intaken piled fathom (IPF) was a measure of volume used for the shipment of pit props. A fathom was six feet and so this was equivalent to 216 cubic feet.
See also
Board foot
Standard (timber unit)
References
Customary units of measurement
Units of volume | Cubic fathom | [
"Mathematics"
] | 62 | [
"Units of volume",
"Quantity",
"Customary units of measurement",
"Units of measurement"
] |
62,401,574 | https://en.wikipedia.org/wiki/Providence%2C%20Rhode%20Island%20Combined%20Sewer%20Overflow%20Abatement%20Program | The Providence, Rhode Island Combined Sewer Overflow Abatement Program is a public works project in Rhode Island.
Background
A combined sewer system is a sewer system that is designed to carry both wastewater and stormwater. In the United States, there are around 860 communities with combined sewer systems, totaling to a population of around 40 million people served. During normal operation of a combined sewer system, the sewage from commercial, industrial, and residential sources flow into the combined system. Water from surface runoff and storm drains join the sewer flow and the combined water and sewage travel to a treatment plant. This is normally not too much of a problem as long as the infrastructure can handle the flow. The issues arise when there is an excess of stormwater. When there is an excess of stormwater, the combined sewer is no longer able to handle the flow and it backs up and drains, usually into the nearest body of water.
Providence, Rhode Island is a place that has had a particular issue when it came to the effects of its combined sewer system. Prior to the start of the project to expand the storage capacity of the combined sewer system, each year the combined sewer overflows would release approximately 2.2 billion gallons of untreated combined sewage. This overflow contained many pollutants that heavily polluted many parts of the Narraganset Bay. This caused many areas to be considered a health risk. This caused there to be certain areas that are permanently closed to shellfishing and over 11,000 acres that would be closed when there was more than an inch of rainfall.
History
In March 1993, the Narragansett Bay Commission approved a comprehensive Combined Sewer Overflow Abatement Program. This three-part plan proposed the construction of seven underground storage facilities and three deep rock tunnel segments. The proposed cost, adjusted for inflation, was $844 million. The plan was eventually approved in 2001, with Phase I completed in 2008. The completion of Phase I diverted around 1.1 billion gallons to a treatment facility at Fields Point. The Phase II facilities were completed in 2014. Due to the high cost of the project, costing around $1.5 billion there was a reevaluation of the project in 2013 with final approval for continuation of Phase III, with additional federal funding in 2019.
Since the construction of Phase I and II, the system is able to capture around 60% of the stormwater that passes through the system. Additionally, it has captured around 11 billion gallons of untreated stormwater. Due to this improvement, the bacteria levels in the Narragansett have dropped by around 50%. The Providence Combined Sewer Overflow Abatement Program is the largest public-works project in Rhode Island History and is working to make the Narragansett Bay cleaner and healthier.
References
Providence, Rhode Island
Sewerage infrastructure | Providence, Rhode Island Combined Sewer Overflow Abatement Program | [
"Chemistry"
] | 575 | [
"Water treatment",
"Sewerage infrastructure"
] |
62,401,582 | https://en.wikipedia.org/wiki/H4K20me | H4K20me is an epigenetic modification to the DNA packaging protein Histone H4. It is a mark that indicates the methylation at the 20th lysine residue of the histone H4 protein. This mark can be mono-, di-, or tri-methylated. It is critical for genome integrity including DNA damage repair, DNA replication and chromatin compaction.
H4K20me2 is the most common methylation state on histone H4 and was one of the earliest modified histone residues to be identified back in pea and calf extracts in 1969. It is one of only two identified methylated lysine residues on the H4 histone, the other being monomethylated H4K12.
Each degree of methylation at H4K20 has a very different cellular process. The loss of H4K20me3 along with a reduction of H4K16ac is a strong indicator of cancer.
Nomenclature
H4K20me indicates monomethylation of lysine 20 on histone H4 protein subunit:
Lysine methylation
This diagram shows the progressive methylation of a lysine residue. The mono-methylation (second from left) denotes the methylation present in H4K20me.
H4K20me exists in three distinct states as mono-, di- and trimethylation.
H4K20me1
H4K20me1 is associated with transcriptional activation.
H4K20me2
H4K20me2 is similar to H4K20me1 but has a different distribution and this dimethylation controls the cell cycle and DNA damage response.
H4K20me3
H4K20me3 is very different. H4K20me3 represses transcription when present at promoters. H4K20me3 also silences repetitive DNA and transposons. The loss of H4K20me3 defines cancer along with a reduction of H4K16ac.
H4K20me3 is involved in Hutchinson-Gilford Progeria syndrome where patients have premature and very rapid aging caused by de novo mutations that occurs in a gene that encodes lamin A. Lamin A is made but isn't processed properly. This poor processing creates a really abnormal nuclear morphology and disorganized heterochromatin. Patients also don't have appropriate DNA repair, and they also have increased genomic instability.
Cancer marker
The loss of the repressive H4K20me3 mark defines cancer along with a reduction of activating H4K16ac mark. It is not clear how the loss of a repressive and an activating mark is an indicator of cancer. It is not clear exactly how but this reduction happens at repetitive sequences along with general reduced DNA methylation.
Histone modifications
The genomic DNA of eukaryotic cells is wrapped around special protein molecules known as histones. The complexes formed by the looping of the DNA are known as chromatin. The basic structural unit of chromatin is the nucleosome: this consists of the core octamer of histones (H2A, H2B, H3 and H4) as well as a linker histone and about 180 base pairs of DNA. These core histones are rich in lysine and arginine residues. The carboxyl (C) terminal end of these histones contribute to histone-histone interactions, as well as histone-DNA interactions. The amino (N) terminal charged tails are the site of the post-translational modifications, such as the one seen in H3K36me3.
Epigenetic implications
The post-translational modification of histone tails by either histone modifying complexes or chromatin remodelling complexes are interpreted by the cell and lead to complex, combinatorial transcriptional output. It is thought that a Histone code dictates the expression of genes by a complex interaction between the histones in a particular region. The current understanding and interpretation of histones comes from two large scale projects: ENCODE and the Epigenomic roadmap. The purpose of the epigenomic study was to investigate epigenetic changes across the entire genome. This led to chromatin states which define genomic regions by grouping the interactions of different proteins and/or histone modifications together.
Chromatin states were investigated in Drosophila cells by looking at the binding location of proteins in the genome. Use of ChIP-sequencing revealed regions in the genome characterised by different banding. Different developmental stages were profiled in Drosophila as well, an emphasis was placed on histone modification relevance. A look in to the data obtained led to the definition of chromatin states based on histone modifications.
The human genome was annotated with chromatin states. These annotated states can be used as new ways to annotate a genome independently of the underlying genome sequence. This independence from the DNA sequence enforces the epigenetic nature of histone modifications. Chromatin states are also useful in identifying regulatory elements that have no defined sequence, such as enhancers. This additional level of annotation allows for a deeper understanding of cell specific gene regulation.
History
H4K20 was one of the earliest modified histone residues to be identified back in pea and calf extracts in 1969.
Genome integrity
H4K20me is important for DNA damage repair, DNA replication and chromatin compaction.
There are a set of H4K20-specific histone methyltransferases (SET8/PR-Set7, SUV4-20H1 and SUV4-20H2). Without these enzymes there is a disruption of genomic instability.
Methods
The histone mark H4K20me can be detected in a variety of ways:
1. Chromatin Immunoprecipitation Sequencing (ChIP-sequencing) measures the amount of DNA enrichment once bound to a targeted protein and immunoprecipitated. It results in good optimization and is used in vivo to reveal DNA-protein binding occurring in cells. ChIP-Seq can be used to identify and quantify various DNA fragments for different histone modifications along a genomic region.
2. Micrococcal Nuclease sequencing (MNase-seq) is used to investigate regions that are bound by well positioned nucleosomes. Use of the micrococcal nuclease enzyme is employed to identify nucleosome positioning. Well positioned nucleosomes are seen to have enrichment of sequences.
3. Assay for transposase accessible chromatin sequencing (ATAC-seq) is used to look in to regions that are nucleosome free (open chromatin). It uses hyperactive Tn5 transposon to highlight nucleosome localisation.
See also
Histone methylation
Histone methyltransferase
Methyllysine
References
Epigenetics
Post-translational modification | H4K20me | [
"Chemistry"
] | 1,446 | [
"Post-translational modification",
"Gene expression",
"Biochemical reactions"
] |
62,401,725 | https://en.wikipedia.org/wiki/Taxon%20cycle | Taxon cycles refer to a biogeographical theory of how species evolve through range expansions and contractions over time associated with adaptive shifts in the ecology and morphology of species. The taxon cycle concept was explicitly formulated by biologist E. O. Wilson in 1961 after he surveyed the distributions, habitats, behavior and morphology of ant species in the Melanesian archipelago.
Stages of the taxon cycle
Wilson categorized species into evolutionary "stages", which today are commonly described in the outline by Ricklefs & Cox (1972). However, with the advent of molecular techniques to construct time-calibrated phylogenetic relationships between species, the taxon cycle concept was further developed to include well-defined temporal scales and combined with concepts from ecological succession and speciation cycle theories. Taxon cycles have mainly been described in island settings (archipelagos), where the distributions and movements of species are readily recognized, but may also occur in continental biota.
Stage I: Young, rapidly expanding, undifferentiated, widely and continuously distributed species in the initial colonization stage inhabiting small island, coastal or disturbed (marginal) habitat. Such species are hypothesized to include very good dispersers, ephemeral species and ecological "supertramps".
Stage II: Species that are generally widespread across many islands, but where geographical expansion has slowed, population differentiation has generated subspecies or incipient species, and local extinction on small islands may have created gaps in the distribution. This stage includes species that have maintained a relatively good dispersal ability such as "great speciators". Early-stage "species complexes" may consist of stage II species.
Stage III: Older, well-differentiated and well-defined species that have moved to habitats inland (and uphill) and where reduced dispersal ability and extinctions have fragmented the distribution to fewer and larger islands. These species may be niche specialists, but novel adaptations or accidental dispersal may restart the taxon cycle.
Stage IV: Old, relictual, endemic species in the "final" stage are restricted to island interiors (mountains) on a few, large islands. This stage includes sedentary high‐elevation specialists with limited dispersal abilities and small range sizes. These species are evolutionary distinctive, as closely related species (and subspecies) have gone extinct.
The ecology and evolution of the Melanesian ants that originally inspired Wilson's hypothesis have since been shown to be consistent with the taxon cycle predictions using modern methods. Ricklefs & Bermingham (2002) estimated that taxon cycles take place over periods of 0.1-10 million years in different bird groups of the Lesser Antilles islands. Pepke et al. (2019) used the difference in mean age of late- and early-stage species as a lower estimate (4.7 million years) of the tempo of taxon cycling in an Indo-Pacific bird family.
References
Biogeography | Taxon cycle | [
"Biology"
] | 581 | [
"Biogeography"
] |
62,401,854 | https://en.wikipedia.org/wiki/Free%20disposal | In various parts of economics, the term free disposal implies that resources can be discarded without any cost. For example, a fair division setting with free disposal is a setting where some resources have to be divided fairly, but some of the resources may be left undivided, discarded or donated.
Examples of situations with free disposal are allocation of food, clothes jewels etc. Examples of situations without free disposal are:
Chore division - since all chores must be done.
Allocation of land with an old structure - since the structure may have to be destructed, and destruction is costly.
Allocation of an old car - since the car may have to be carried away to used cars garage, and moving it may be costly.
Allocation of shares in a firm that may have debts - since the firm cannot be disposed of without paying its debts first.
The free disposal assumption may be useful for several reasons:
It enables truthful cake-cutting algorithms: The option to discard some of the cake gives the players an incentive to reveal their true valuations.
It enables fast envy-free cake-cutting algorithms, and more economically-efficient envy-free allocations: Discarding some of the cake helps to reduce envy.
It enables online assignment algorithms.
References
Fair division | Free disposal | [
"Mathematics"
] | 252 | [
"Recreational mathematics",
"Game theory",
"Fair division"
] |
62,402,078 | https://en.wikipedia.org/wiki/Viral%20strategies%20for%20immune%20response%20evasion | The mammalian immune system has evolved complex methods for addressing and adapting to foreign antigens. At the same time, viruses have co-evolved evasion machinery to address the many ways that host organisms attempt to eradicate them. DNA and RNA viruses use complex methods to evade immune cell detection through disruption of the Interferon Signaling Pathway, remodeling of cellular architecture, targeted gene silencing, and recognition protein cleavage.
Interferon system
The human immune system relies on a plethora of cell-cell signaling pathways to transmit information about a cell's health and microenvironment. Many of these pathways are mediated by soluble ligands, cytokines, that fit like a lock-and-key into adjacent cell surface receptors. This language of cell communication imparts both specificity and spatiotemporal control for the transmission of data.
The Interferon System is composed of a family of cytokines. Type-I Interferons, IFN-α/β, and Type-III Interferons, IFN-λ play key roles in adaptive immunity, acting as communication highways between cells infected with foreign double stranded DNA or double stranded RNA. Mammalian cells utilize specialized receptors known as Pattern Recognition Receptors(PRRs) to detect viral infection; these receptors are able to recognize pathogen-associated molecular patterns (PAMPs) inscribed in viral DNA and RNA. These pattern recognition receptors, often localized to either the cytosol or the nucleus, are responsible for notifying infected cells and initiating the secretion of interferon cytokines.
Double-stranded RNA mediated immune response
The precise role of double-stranded (ds)RNA is still widely investigated as a central player in the Interferon System. Groups have found that positive-strand RNA viruses and dsRNA viruses produced significant amounts of dsRNA, but the precise methods mammalian cells leverage to distinguish between self vs. non-self dsRNA have yet to be uncovered. Studies suggest that recognition must extend beyond simple identification of dsRNA structure and likely relies on other epigenetic markers.
Double-stranded RNA recognition
Protein kinase activation
dsRNA has been implicated in the activation of the interferon system through the activation of Protein Kinase R, PKR. Cytoplasmic PKR is often associated with the ribosome in mammalian cells where it is able to recognize double-stranded and single-stranded RNA and subsequently phosphorylate varies substrates, arresting protein synthesis. The activation of PKR subsequently triggers interferon signaling, initiating cell death in response to viral dsRNA recognition. While the PKR The roles of PKR activation have been deeply studied with groups finding that it is insensitive to the presence of short dsRNA and siRNA but showing significant affinity for dsRNA and ssRNA with secondary structure.
2'-5'- Oligoadenylate synthetase
Groups have found that the Interferon Signaling promotes the activation of a 2'-5'-oligoadenylate synthetase, sensitive to the presence of dsRNA longer than 15 base pairs. Because this mechanism is not sensitive to self vs. non-self dsRNA binding, results indicate overall reduction in protein synthesis but indicated no specificity for a sole reduction of viral protein synthesis.
Viral evasion strategies
In recent years, studies have focused on how viruses evade Pattern Recognition Receptors, target adaptor proteins and their kinases, inhibit transcription factors for Interferon induction, and evade Interferon Stimulated Genes.
Pattern recognition receptor evasion
Viruses of the flaviviridae Family, such as hepatitis C virus, have developed complex viral mechanisms to rearrange the cell membrane, creating a membranaceous web designed to house viral replication machinery. These viruses utilize endogenous host cell nuclear pore complex proteins to shield viral RNA from Pattern Recognition Receptors by excluding PRRs from the interior of the viral membrane compartment. By utilizing architectural rearrangement of the membrane, viruses have developed a method to evade cytoplasm localized pattern recognition proteins such as RIG-I. In order to evade pattern recognition, other viruses such as Enterovirus have evolved multi-functional proteins that not only help in viral protein processing but also cleave cytoplasmic recognition proteins MDA5 and RIG-I, further demonstrating the extent to which viruses can reduce Interferon Signaling through various pathways. Other viruses have been reported to target upstream activators of pattern recognition proteins, antagonizing upstream proteins that removed inhibitory post-translational modifications.
Nucleic acid shielding
Other viruses utilize host cell proteins to shield viral DNA until it has reached the nucleus. Upon entry into the host cell cytoplasm, the HIV-1 capsid is recognized and bound by cyclophilin A (CypA); this affinity interaction stabilizes the capsid and prevents exposure of the HIV-1 cDNA to pattern recognition receptors in the cytoplasm. This shielding allows the HIV-1 cDNA to translocate to the nucleus where it may begin replication.
References
Virology
Evolutionary biology | Viral strategies for immune response evasion | [
"Biology"
] | 1,026 | [
"Evolutionary biology"
] |
62,402,446 | https://en.wikipedia.org/wiki/International%20Journal%20of%20Geomechanics | The International Journal of Geomechanics is a monthly peer-reviewed scientific journal published by the American Society of Civil Engineers that focuses on geomechanics, emphasizing theoretical aspects, to include computational and analytical methods, and related validations.
Abstracting and indexing
The journal is indexed in Ei Compendex, ProQuest databases, Civil Engineering Database, Inspec, Science Citation Index Expanded, and EBSCO databases.
References
External links
American Society of Civil Engineers academic journals
Mining journals
Geotechnical engineering
Engineering geology journals | International Journal of Geomechanics | [
"Engineering"
] | 109 | [
"Civil engineering",
"Geotechnical engineering"
] |
62,403,302 | https://en.wikipedia.org/wiki/Functional%20ultrasound%20imaging | Functional ultrasound imaging (fUS) is a medical ultrasound imaging technique for detecting or measuring changes in neural activities or metabolism, such as brain activity loci, typically through measuring hemodynamic (blood flow) changes. It is an extension of Doppler ultrasonography.
Background
Brain activation can be directly measured by imaging electrical activity of neurons using voltage-sensitive dyes, calcium imaging, electroencephalography, or magnetoencephalography. It can also be indirectly measured hemodynamically, that is, by detecting changes in blood flow in the neurovascular systems through functional magnetic resonance imaging (fMRI), positron emission tomography (PET), Functional near-infrared spectroscopy (fNIRS), or Doppler ultrasonography, etc.
Optics-based methods generally provide the highest spatial and temporal resolutions; however, due to scattering, they are limited to measuring regions close to the surface. Thus, they are often used on animal models after partially removing or thinning the skull to allow light to penetrate into brain tissue.
fMRI and PET, which measure the blood-oxygen level dependent (BOLD) signal, were the only techniques capable of imaging brain activation in depth. BOLD signal increases when neuronal activation exceeds oxygen consumption, where blood flow increases significantly, resulting in cerebral blood volume (CBV) changes. This relationship between neuronal activity and blood flow is called neurovascular coupling. In fact, in-depth imaging of cerebral hemodynamic responses by fMRI, being noninvasive, paved the way for major discoveries in neurosciences in the early stage, and is applicable on humans.
However, fMRI also suffers limitations. First, the cost and size of MRI machines can be prohibitive. Second, for fMRI to achieve a high spatial resolution necessarily decreases its time resolution and/or signal-noise ratio. As a result, it is hard to image fine spatial details of transient events such as epilepsy. Finally, fMRI is not appropriate for all clinical applications. For example, fMRI is rarely performed on infants, because infants do not stay still inside MRI machines.
Like fMRI, Doppler-based functional ultrasound is based on the neurovascular coupling and are thus limited by the spatiotemporal features of neurovascular coupling, specifically cerebral blood volume (CBV) changes. CBV is a pertinent parameter for functional imaging that is already used by other modalities such as intrinsic optical imaging or CBV-weighted fMRI. The spatiotemporal extent of CBV response was extensively studied. The spatial resolution of sensory-evoked CBV response can go down to cortical column (~100 μm). Temporally, the CBV impulse response function was measured to typically start at ~0.3 s and peak at ~1 s in response to ultrashort stimuli (300μs), which is much slower than the underlying electrical activity.
Conventional Doppler based approaches
Hemodynamic changes in the brain are often used as a surrogate indicator of neuronal activity to map the loci of brain activity. Major part of the hemodynamic response occurs in small vessels; however, conventional Doppler ultrasound is not sensitive enough to detect the blood flow in such small vessels.
Functional transcranial Doppler (fTCD)
Ultrasound Doppler imaging can be used to obtain basic functional measurements of brain activity using blood flow. In functional transcranial Doppler sonography, a low frequency (1-3 MHz) transducer is used through the temporal bone window with a conventional pulse Doppler mode to estimate blood flow at a single focal location. The temporal profile of blood velocity is usually acquired in main large arteries such as the middle cerebral artery (MCA). The peak velocity is compared between rest and task conditions or between right and left sides when studying lateralization.
The temporal window is the thinnest lateral area of the skull, and it is mostly hairless. It is often used for fTCD.
Power Doppler
Power Doppler is a Doppler sequence that measures the ultrasonic energy backscattered from red blood cells in each pixel of the image. It provides no information on blood velocity but is proportional to blood volume within the pixel. However, conventional power Doppler imaging lacks sensitivity to detect small arterioles/venules and thus is unable to provide local neurofunctional information through neurovascular coupling.
Ultrasensitive Doppler imaging
Functional ultrasound imaging was pioneered at ESPCI by 's team following work on ultrafast imaging and ultrafast Doppler.
Principles
Ultrasensitive Doppler relies on ultrafast imaging scanners able to acquire images at thousands of frames per second (~1 kHz), thus boosting the SNR of power Doppler without any contrast agents. Instead of the line by line acquisition of conventional ultrasound devices, ultra-fast ultrasound takes advantage of successive tilted plane wave transmissions that afterward coherently compounded to form images at high frame rates. Coherent Compound Beamforming consists of the recombination of backscattered echoes from different illuminations achieved on the acoustic pressure field with various angles (as opposed to the acoustic intensity for the incoherent case). All images are added coherently to obtain a final compounded image. This very addition is produced without taking the envelope of the beamformed signals or any other nonlinear procedure to ensure a coherent addition. As a result, coherent adding of several echo waves leads to cancellation of out-of-phase waveforms, narrowing the point spread function (PSF), and thus increasing spatial resolution. A theoretical model demonstrates that the gain in sensitivity of the ultrasensitive Doppler method is due to the combination of the high signal-to-noise ratio (SNR) of the gray scale images, due to the synthetic compounding of backscattered echoes and the extensive signal samples averaging due to the high temporal resolution of ultrafast frame rates. The sensitivity was recently further improved using multiple plane wave transmissions and advanced spatiotemporal clutter filters for better discrimination between low blood flow and tissue motion. Ultrasound researchers have been using ultrafast imaging research platforms with parallel acquisition of channels and custom sequences programming to investigate ultrasensitive Doppler/fUS modalities. A custom real-time high-performance GPU beamforming code with a high data transfer rate (several GB/s) must then be implemented to perform imaging at high frame rate. Acquisitions can also typically easily provide gigabytes of data depending on acquisition duration.
Ultrasensitive Doppler has a typical 50-200 μm spatial resolution depending on the ultrasound frequency used. It features temporal resolution ~10 ms, can image the full depth of the brain, and can provide 3D angiography.
functional ultrasound imaging
This signal boost enables the sensitivity required to map subtle blood variations in small arterioles (down to 1mm/s) related to neuronal activity. By applying an external stimulus such as a sensory, auditory or visual stimulation, it is then possible to construct a map of brain activation from the ultrasensitive Doppler movie.
Functional ultrasound (fUS) measures indirectly cerebral blood volume which provides an effect size close to 20% and as such is quite more sensitive than fMRI whose BOLD response is typically only a few percents. Correlation maps or statistical parametric maps can be constructed to highlight the activated areas. fUS has been shown to have a spatial resolution on the order of 100 μm at 15 MHz in ferrets and is sensitive enough to perform single trial detection in awake primates. Other fMRI-like modalities such as functional connectivity can also be implemented.
Commercial scanners with specialized hardware and software are enabling fUS to rapidly expand behind ultrasound research labs to the neuroscience community.
4D functional ultrasound imaging
4D functional ultrasound imaging (4D fUS) means fUS imaging of a 3D region of the brain over time.
Some researchers conducted 4D fUS of whole-brain activity in rodents. Currently, two different technological solutions are proposed for the acquisition of 3D and 4D fUS data, each with its own advantages and drawbacks. The first is a tomographic approach based on motorized translation of linear probes. This approach proved to be a successful method for several applications such as 3D retinotopic mapping in the rodent brain and 3D tonotopic mapping of the auditory system in ferrets. The second approach relies on high frequency 2D matrix array transducer technology coupled with a high channel count electronic system for fast 3D imaging. To counterbalance the intrinsically poor sensitivity of matrix elements, they devised a 3D multiplane-wave scheme with 3D spatiotemporal encoding of transmit signals using Hadamard coefficients. For each transmission, the backscattered signals containing mixed echoes from the different plane waves are decoded using the summation of echoes from successive receptions with appropriate Hadamard coefficients. This summation enables the synthetic building of echoes from a virtual individual plane wave transmission with a higher amplitude. Finally, they perform coherent compounding beamforming of decoded echoes to produce 3D ultrasonic images and apply a spatiotemporal clutter filter separating blood flow from tissue motion to compute a power Doppler volume, which is proportional to the cerebral blood volume.
Applications
Preclinical
fUS can benefit in monitoring cerebral function in the whole brain which is important to understanding how the brain works on a large scale under normal or pathological conditions. The ability to image cerebral blood volume at high spatiotemporal resolution and with high sensitivity using fUS could be of great interest for applications in which fMRI reaches its limits, such as imaging of epileptic-induced changes in blood volume. fUS can be applied for chronic studies in animal models through a thinned-skull or smaller cranial window or directly through the skull in mice.
Brain activity mapping
Tonotopics or retinotopics maps can be constructed by mapping the response of frequency-varying sounds or moving visual targets.
Functional connectivity / resting state
When no stimulus is applied, fUS can be used to study functional connectivity during resting state. The method has been demonstrated in rats and awake mice and can be used for pharmacological studies when testing drugs. Seed-based maps, independent component analysis of resting states modes or functional connectivity matrix between atlas-based regions of interests can be constructed with high resolution.
Awake fUS imaging
Using dedicated ultralight probes, it is possible to perform freely-moving experiments in rats or mice. The size of the probes and electromagnetic-compatibility of fUS means it can also be used easily on head-fixed setups for mice or in electrophysiology chambers in primate.
Clinical
Neonates
Thanks to its portability, fUS has also been used in clinics in awake neonates. Functional ultrasound imaging can be applied to neonatal brain imaging in a non-invasive manner through the fontanel window. Ultrasound is usually performed in this case, which means that the current procedures does not have to be changed. High quality angiographic images could help diagnose vascular diseases such as perinatal ischemia or ventricular hemorrhage.
Adults / intraoperative
For adults, this method can be used during neurosurgery to guide the surgeon through the vasculature and to monitor the patient's brain function prior to tumor resection
See also
functional magnetic resonance imaging (fMRI)
Functional neuroimaging
References
Ultrasound
Magnetic resonance imaging | Functional ultrasound imaging | [
"Chemistry"
] | 2,373 | [
"Nuclear magnetic resonance",
"Magnetic resonance imaging"
] |
62,404,339 | https://en.wikipedia.org/wiki/Headless%20engine | A headless engine or fixed head engine is an engine where the end of the cylinder is cast as one piece with the cylinder and crankcase. The most well known headless engines are the Fairbanks-Morse Z and the Witte Headless hit and miss engine
See also
Monobloc engine
References
Engines | Headless engine | [
"Physics",
"Technology",
"Engineering"
] | 62 | [
"Machines",
"Engines",
"Physical systems",
"Mechanical engineering",
"Mechanical engineering stubs"
] |
62,404,586 | https://en.wikipedia.org/wiki/List%20of%20construction%20methods | The list of construction methods covers the processes and techniques used in the construction process. The construction method is essential for civil engineers; utilizing it appropriately can help to achieve the desired results. The term building refers to the creation of physical structures such as buildings, bridges or railways. One of the four types of buildings is residential and building methods are easiest to study in these structures.
Background
Construction involves the creation of physical structures such as buildings, bridges or railways.
Bricks are small rectangular blocks that can be used to form parts of buildings, typically walls. Before 7,000 BC, bricks were formed from hand-molded mud and dried by the sun. During the Industrial Revolution, mass-produced bricks became a common alternative to stone. Stone was typically more expensive, less predictable and more difficult to handle. Bricks remain in common use. They are small and easy to handle, strong in compression, durable and low maintenance. They can be formed into complex shapes, providing ample opportunity for the construction of aesthetic designs.
The four basic types of structure are residential, institutional and commercial, industrial, and infrastructure/heavy.
Residential
Residential buildings go through five main stages, including foundations, formwork, scaffolding, concrete work and reinforcement.
Foundation
Foundations provide support for structures, transferring their load to layers of soil or rock that have sufficient bearing capacity and suitable settlement characteristics to support them. There are four types of foundation depending on the bearing capacity. Civil engineers will often determine what type of foundation is suitable for the respective bearing capacity.
The foundation construction method depends on considerations such as:
The nature of the load requiring support
Ground conditions
The presence of water
Space availability
Accessibility
Sensitivity to noise and vibration
Shallow foundation
Shallow foundations are used where the loads forced by a structure are low relative to the bearing capacity of the surface soils. Deep foundations are needed where the bearing capacity of the surface soils is insufficient. Those loads need to be transferred to deeper layers with higher bearing capacity.
Raft or mat foundation
Raft foundations are slabs that cover a wide area, often the entire building footprint. They are suitable where ground conditions are too poor to create individual strip or pad foundations for a large number of individual loads. Raft foundations may combine beams to add support for specific loads.
Pile foundation
Pile foundations are rectangular or circular pads used to support loads such as columns.
Strip foundation
Strip foundations provide a continuous line of support to a linear structure such as a wall. Trench fill foundations are a variation of strip foundations. The trench excavation is almost completely filled with concrete. Rubble trench foundations are a further variation of trench fill foundations and are a traditional construction method that uses loose stone or rubble to minimise the use of concrete and improve drainage.
Formwork
Formwork is used for the process of creating a mold into which concrete is poured and solidified. Traditional formwork is fabricated using wood, but it can employ steel, glass fibre, reinforced plastics and other materials.
Formwork for beams takes the form of a box that is supported and propped in the correct position and level. The removal time for the formwork will vary with air temperature, humidity and consequent curing rate. Typical striking times are as follows (using air temperature of 7-16 °C):
Beam sides: 9–12 hours.
Beam soffits: 8–14 days.
Beam props: 15–21 days.
This consists of a vertical mold of the desired shape and size matching the column to be poured. To keep the material thickness to a minimum, horizontal steel or timber clamps (or yokes) are used for batch filling and at varying centers for filling that is completed in one pour.
The head of the column can provide support for the beam formwork. Even though this gives good top lateral restraint, it can make the formwork complex. The column can be cast to the underside of the beams. A collar of formwork can be held around the cast column to complete the casting and support the incoming beam.
Falsework
Falsework consists of temporary structures used to support a permanent structure. Falsework need to have accurate calculation.
Bar bending
Rebar is a steel bar or mesh of steel wires used in reinforced concrete and masonry structures to strengthen and hold the concrete in tension. The surface of rebar is often patterned to improve the quality of the bond with the concrete. Rebar is necessary to add tensile strength, while concrete is strong in compression. It can support tensile loads and increase overall strength by casting rebar into concrete.
Concrete
Concrete is typically used in commercial buildings and civil engineering projects, for its strength and durability. Concrete is a mix of cement and water plus an aggregate such as sand or stone. Its compression strength means it can support heavy weights.
Insulating concrete forms (ICFs) cam be used for home construction. They are made by pouring concrete between rigid panels, often made out of polystyrene foam. Rebar can provide additional strength internally, and the exterior panels can remain in place once the concrete sets. It is essential to check the levels of foundation before pouring.
Brick
Bricks are laid with a mortar joint bonding them. The profile of the mortar can be varied depending on exposure or to create a specific visual effect. The most common profiles are flush (rag joint), bucket handle, weather struck, weather struck and cut and recessed.
The bonding pattern describes the alignment of the bricks. Many standard bond patterns have been defined, including stretcher bond. Each stretcher (brick laid lengthwise) is offset by half a brick relative to the courses above and below of English bond. Stretchers and headers are laid with alternating courses aligned to one another. American common bond is similar to the English bond but with one course of headers for every six stretcher courses. English cross bond has courses of stretchers and headers, but with the alternating stretcher courses offset by half a brick.
Flemish bond consists of alternating stretchers and headers in each course. Header bond has courses of headers offset by half a brick. Stack bond consists of bricks laid directly on top of one another with joints aligned. This is a weak bond and is likely to require reinforcement. Garden wall bond has three courses of stretchers then one course of headers. Sussex bond has three stretchers and one header in each course.
References
Construction | List of construction methods | [
"Engineering"
] | 1,262 | [
"Construction"
] |
62,405,231 | https://en.wikipedia.org/wiki/Peter%20Kee%20Lin%20Ng | Peter Kee Lin Ng (born 1960) is a Singaporean carcinologist and ichthyologist at the National University of Singapore, concurrently working as Director of both the Lee Kong Chian Natural History Museum and the Tropical Marine Science Institute. He has written extensively with over 510 technical papers, mostly in international journals - his research is primarily on the diversity and biology of marine and freshwater crabs in the Indo-West Pacific. He has many awards, the Singapore National Youth Award (Excellence in Science and Technology), National Youth Movement, People's Association (1993); the National Science Award 1995, National Science & Technology Board, Ministry of Trade and Development; and the ASEAN Young Science and Technologist Award, ASEAN Science and Technology Ministers, 4th ASEAN Science Ministers Meeting, Bangkok (1995).
Taxa described by him
See :Category:Taxa named by Peter Kee Lin Ng
References
Living people
Taxon authorities
Singaporean ichthyologists
1960 births | Peter Kee Lin Ng | [
"Biology"
] | 189 | [
"Taxon authorities",
"Taxonomy (biology)"
] |
62,405,866 | https://en.wikipedia.org/wiki/Cereceda%27s%20conjecture | In the mathematics of graph coloring, Cereceda’s conjecture is an unsolved problem on the distance between pairs of colorings of sparse graphs. It states that, for two different colorings of a graph of degeneracy , both using at most colors, it should be possible to reconfigure one coloring into the other by changing the color of one vertex at a time, using a number of steps that is quadratic in the size of the graph. The conjecture is named after Luis Cereceda, who formulated it in his 2007 doctoral dissertation.
Background
The degeneracy of an undirected graph is the smallest number such that every non-empty subgraph of has at least one vertex of degree at most . If one repeatedly removes a minimum-degree vertex from until no vertices are left, then the largest of the degrees of the vertices at the time of their removal will be exactly , and this method of repeated removal can be used to compute the degeneracy of any graph in linear time. Greedy coloring the vertices in the reverse of this removal ordering will automatically produce a coloring with at most colors, and for some graphs (such as complete graphs and odd-length cycle graphs) this number of colors is optimal.
For colorings with colors, it may not be possible to move from one coloring to another by changing the color of one vertex at a time. In particular, it is never possible to move between 2-colorings of a forest (the graphs of degeneracy 1) or between -colorings of a complete graph in this way; their colorings are said to be frozen. Cycle graphs of length other than four also have disconnected families of -colorings.
However, with one additional color, using colorings with colors, all pairs of colorings can be connected to each other by sequences of moves of this type. It follows from this that an appropriately designed random walk on the space of -colorings, using moves of this type, is mixing. This means that the random walk will eventually converge to the discrete uniform distribution on these colorings as its steady state, in which all colorings have equal probability of being chosen. More precisely, the random walk proceeds by repeatedly choosing a uniformly random vertex and choosing uniformly at random among all the available colors for that vertex, including the color it already had; this process is called the Glauber dynamics.
Statement
The fact that the Glauber dynamics converges to the uniform distribution on -colorings naturally raises the question of how quickly it converges. That is, what is the mixing time? A lower bound on the mixing time is the diameter of the space of colorings, the maximum (over pairs of colorings) of the number of steps needed to change one coloring of the pair into the other. If the diameter is exponentially large in the number of vertices in the graph, then the Glauber dynamics on colorings is certainly not rapidly mixing. On the other hand, when the diameter is bounded by a polynomial function of , this suggests that the mixing time might also be polynomial. In his 2007 doctoral dissertation, Cereceda investigated this problem, and found that (even for connected components of the space of colors) the diameter can be exponential for -colorings of -degenerate graphs. On the other hand, he proved that the diameter of the color space is at most quadratic (or, in big O notation, ) for colorings that use at least colors. He wrote that "it remains to determine" whether the diameter is polynomial for numbers of colors between these two extremes, or whether it is "perhaps even quadratic".
Although Cereceda asked this question for a range of colors and did not phrase it as a conjecture, by 2018 a form of this question became known as Cereceda's conjecture. This unproven hypothesis is the most optimistic possibility among the questions posed by Cereceda: that for graphs with degeneracy at most , and for -colorings of these graphs, the diameter of the space of colorings is .
If true, this would be best possible, as the space of 3-colorings of a path graph has quadratic diameter.
Partial and related results
Although Cereceda's conjecture itself remains open even for degeneracy , it is known that for any fixed value of the diameter of the space of -colorings is polynomial (with a different polynomial for different values of ). More precisely, the diameter is . When the number of colors is at least , the diameter is quadratic.
A related question concerns the possibility that, for numbers of colors greater than , the diameter of the space of colorings might decrease from quadratic to linear. suggest that this might be true whenever the number of colors is at least .
The Glauber dynamics is not the only way to change colorings of graphs into each other. Alternatives include the Kempe dynamics in which one repeatedly finds and swaps the colors of Kempe chains, and the "heat bath" dynamics in which one chooses pairs of adjacent vertices and a valid recoloring of that pair. Both of these kinds of moves include the Glauber one-vertex moves as a special case, as changing the color of one vertex is the same as swapping the colors on a Kempe chain that only includes that one vertex. These moves may have stronger mixing properties and lower diameter of the space of colorings. For instance, both the Kempe dynamics and the heat bath dynamics mix rapidly on 3-colorings of cycle graphs, whereas the Glauber dynamics is not even connected when the length of the cycle is not four.
References
Conjectures
Graph coloring
Reconfiguration | Cereceda's conjecture | [
"Mathematics"
] | 1,166 | [
"Unsolved problems in mathematics",
"Graph coloring",
"Reconfiguration",
"Graph theory",
"Computational problems",
"Conjectures",
"Mathematical relations",
"Mathematical problems"
] |
62,406,548 | https://en.wikipedia.org/wiki/Aidoc | Aidoc Medical is an Israeli technology company that develops computer-aided simple triage and notification systems. Aidoc has obtained FDA and CE mark approval for its stroke, pulmonary embolism, cervical fracture, intracranial hemorrhage, intra-abdominal free gas, and incidental pulmonary embolism algorithms.
Aidoc algorithms are in use in more than 900 hospitals and imaging centers, including Montefiore Nyack Hospital, LifeBridge Health, LucidHealth, Yale New Haven Hospital, Cedars-Sinai Medical Center, University of Rochester Medical Center, and Sheba Medical Center.
History
Aidoc was founded in 2016 by Elad Walach as the CEO, Michael Braginsky as the CTO and Guy Reiner as the VP. In April 2017, the company raised $7M, led by TLV Partners, and in April 2019, the company raised another $27M, led by Square Peg capital.
In August 2018, Aidoc gained FDA clearance for its intracranial hemorrhage system, and in May 2019 it received clearance for the pulmonary embolism system.
In January 2020, the system for detecting large-vessel occlusions (LVOs) in head CTA examinations obtained FDA clearance.
Products and market
Aidoc has developed a suite of artificial intelligence products that flag both time-sensitive and time-consuming (for the radiologist) abnormalities across the body. The algorithms are developed with large quantities of data to provide diagnostic aid for a broad set of pathologies. The company offers an array of algorithms that span across the body, including for intracranial hemorrhage, spine fractures (C, T & L), free air in the abdomen, pulmonary embolism, and more. It developed "Always-on AI", a term coined by Elad Walach that refers to a type of artificial intelligence that is "Always-on—constantly running in the background and automatically analyzing medical imaging data, identifying urgent findings, and sparing radiologists from "drowning" in vast amounts of irrelevant data.
Aidoc's solutions cover medical conditions prevalent in all settings (ED/inpatient/outpatient), including level 1 trauma centers, outpatient imaging centers, teleradiology groups and, are set up in over 200 medical centers worldwide. Notable customers include the University of Rochester Medical Center and Global Diagnostics Australia.
Clinical Research
A clinical study on Aidoc’ accuracy of deep convolutional neural networks for the detection of pulmonary embolism (PE) on CT pulmonary angiograms (CTPAs) was performed by the University Hospital of Basel and presented at the European Congress of Radiology, showing that the Aidoc algorithm reached 93% sensitivity and 95% specificity. Clinical research has also been performed to test the diagnostic performance of Aidoc's deep learning-based triage system for the flagging of acute findings in abdominal computed tomography (CT) examinations. Overall, the algorithm achieved 93% sensitivity (91/98, 7 false negatives) and 97% specificity (93/96, 3 false-positive) in the detection of acute abdominal findings.
Additional clinical research on Aidoc's Intracranial hemorrhage algorithm accuracy was presented at the European Congress of Radiology by Antwerp University Hospital, evaluating the use of its deep learning algorithm for the detection of intracranial hemorrhage on non-contrast enhanced CT of the brain. The University of Washington completed a study on the accuracy of Aidoc's intracranial hemorrhage algorithm.
References
External links
Official website
Medical technology companies of Israel
Medical expert systems
Radiology
Technology companies established in 2016
Applications of artificial intelligence
Health informatics
Israeli companies established in 2016 | Aidoc | [
"Biology"
] | 757 | [
"Health informatics",
"Medical technology"
] |
62,407,042 | https://en.wikipedia.org/wiki/Centre%20for%20Development%20and%20Environment%20%28Switzerland%29 | The Centre for Development and Environment (CDE) is an interdisciplinary research centre specializing in sustainability science and land systems at the University of Bern, Switzerland. It conducts research in many countries worldwide, with a particular focus on the Eastern Africa, Southeast Asia, South America, Europe, and Switzerland. In terms of teaching, CDE offers courses in the field of sustainable development at the bachelor’s, master’s, doctoral, and postdoctoral level.
History
CDE was established in 2009 as a strategic research centre of the University of Bern, under the direction of Peter Messerli and Thomas Breu. Its origins date back to the Group for Development and Environment, founded in 1988 at the Institute of Geography of the University of Bern. This research group was headed by two professors, Hans Hurni and Urs Wiesmann, and initially based on two international research programmes, the Soil Conservation Research Programme in Ethiopia (1981–1998) and the Laikipia Research Programme in Kenya (1984–1997). Other major international research programmes followed. These included Terre Tany (1989–2000) in Madagascar, the Eastern and Southern Africa Partnership Programme (1999–2015), and programmes in Central Asia, the Mekong region, and the Andes. From 2001 to 2013, CDE was the lead institution of the National Centre of Competence in Research (NCCR) North-South, a Swiss-based international research programme on global change and sustainable development.
In 2016, UN Secretary-General Ban Ki-moon appointed then CDE Director Peter Messerli to co-chair the independent group of scientists drafting the Global Sustainable Development Report (GSDR) 2019 on the UN Sustainable Development Goals. Peter Messerli oversaw completion of the milestone report together with co-chair Endah Murniningtyas, former Deputy Minister for Natural Resources and Environment in Indonesia.
Research
CDE conducts research on sustainable development in the context of global change and related impacts on natural resources (soils, water, biodiversity), land systems, and the living conditions of different population groups. It employs researchers from the natural sciences, social sciences, human sciences, humanities, law, and economics. The four main areas of research of CDE’s interdisciplinary teams are:
Land resources: use of natural resources (water, soil, vegetation); importance of land (access, distribution, rights) and changes and adjustments in management (cultivation techniques, conservation, commodification) for sustainable development.
Socio-economic transitions: global change; measuring poverty and inequality; social and technological innovations in the fields of labour, production, and consumption.
Sustainability governance: interaction of global and local regulatory systems; GIS-based methods to identify different claims to water, land, or food; policy support.
Education for sustainable development: building competencies for transformations to sustainable development; supporting the University of Bern in implementing sustainability in teaching, research, and operations.
Teaching
CDE offers a full master's in Sustainabiltiy Transformations and minors in sustainable development at the bachelor’s and master’s level, with currently over 400 students enrolled in these programmes.
The International Graduate School (IGS) North-South was created in 2009 as part of the above-mentioned NCCR North-South programme. The IGS North-South is a doctoral programme based on an inter-university agreement between the Universities of Basel, Bern, Lausanne, and Zurich, as well as selected cooperation agreements with universities in countries of the global South and East. CDE coordinates the IGS North-South, which currently has around 100 doctoral students.
Organization
Administratively, CDE is part of the Faculty of Science of the University of Bern. The university’s Executive Board issues a performance mandate to CDE.
Networks
CDE maintains a broad national and international network with academic institutions such as ProClim, the Swiss Commission for Research Partnerships with Developing Countries KFPE, td-net the Swiss Academic Society for Environmental Research and Ecology (SAGUF), and scnat; global scientific programmes; civil society organizations; and the public sector. It hosts
the coordination office of the Mountain Research Initiative (MRI)
the coordination office of the World Overview of Conservation Approaches and Technologies (WOCAT);
the editorial office of the international peer-reviewed journal Mountain Research and Development (MRD); and
together with Biovision, the Sustainable Development Solutions Network (SDSN) Switzerland.
References
External links
CDE's website
International Graduate School (IGS) North-South
University of Bern
Environmental research institutes | Centre for Development and Environment (Switzerland) | [
"Environmental_science"
] | 910 | [
"Environmental research institutes",
"Environmental research"
] |
67,616,173 | https://en.wikipedia.org/wiki/Bailey%20Nelson | Bailey Nelson (registered as Ben Buckler Eyewear Limited) is an Australian multinational optical retail chain, which operates mainly in Australia, New Zealand and Canada. Bailey Nelson is, as of 2021, a privately held company.
The chain offers optician services for eyesight testing and sells glasses, sunglasses, and contact lenses.
The company has more than 100 branches in Australia, New Zealand and Canada.
History
Bailey Nelson was founded in 2012 by Nick Perry and Peter Winkle in the Bondi Beach area of Sydney, NSW. Perry says they received no outside funding at the start, investing $80,000 of their own savings.
The company started with offering glasses and ventured into contact lenses (including their own store brand) in 2016, if not earlier. They introduced optometry services in their stores in 2014.
Bailey Nelson entered the Canadian market in 2014, but Canadian stores closed in 2017 after a licensing agreement ended. They have since re-entered the Canadian market. In 2019, the brand continued expanding in Canada, with 15 stores as of November 2019, with the plan to "open seven to eight locations (in the 2019 financial year)". In 2015, they had 4 branches in the UK. Also in 2015, they opened up shop in Wellington, New Zealand.
The company ceased operations in the United Kingdom in May 2023, closing their two shops in London and their online store.
Business strategy and partnerships
Part of the way in which Bailey Nelson, and other companies like them, are able to stay competitive is by changing suppliers, and likely working with more independent producers . High level, Bailey Nelson states their purpose is to bypass the "unfair and overpriced" eyewear market with direct-to-consumer alternatives. The product is vertically integrated, with acetate frames designed in-house in Sydney and produced in factories overseas. They also focus strongly on a luxury in-store experience, with the aim to turn a "clinical" optician and glasses purchase process into "one of life’s pleasures."
At a product level, Bailey Nelson started with optical glasses and sunglasses, later expanding to contact lenses. They also offer blue light filters, though some doubt their efficacy. By default their optical and sunglasses have anti-glare and scratch resistant coatings included in the price.
All frames are designed in house and produced by manufacturers in China. The acetate they source is from the company Mazzucchelli 1849, based in Italy. Mazzuchhelli also assisted them in choosing factories to partner with.
Bailey Nelson have reentered the partnership opportunity space, this time in New Zealand and Australia. It's a co-investment model that allows optometrists to own a portion of a Bailey Nelson location, while Bailey Nelson manages the overhead costs like systems, training, supply chain and other support systems.
In Australia, they collaborated with Eugene Tan, the founder and photographer of Aquabumps, in 2015 to launch a capsule sunglasses collection available for a limited time.
In 2019, 2020 and 2021, Bailey Nelson participated in "Afterpay day", also known as AfterYAY day. In many of the countries they operate in, they also offer student discounts or limited-time offers, including Black Friday deals.
In 2020, they responded to COVID-19 by shutting all stores globally, by 27 Mar. By 21 Nov 2020, stores in Australia were re-opening in line with individual state guidelines. Each individual region has had different and staggered responses to COVID-19 protocol.
Business Future
Co-founder Nick Perry stated in 2019 that in the Canadian market, their longer term goal was to be at 50 locations in Canada. With this comes a three-part strategy: focus on optometry, build engaged, passionate staff, and deliver quality differentiating product. This strategy is in part due to the differing medicare coverages of eyecare in Canada versus Australia, the market they started in.
They also have private advisors, including Delaney Schweitzer. As of March 2021, there have been reports of a new investment funding round via Goldman Sachs to help support reportedly aggressive growth plans in all markets in the coming years.
References
Opticians
Companies based in Sydney
Retail companies established in 2012 | Bailey Nelson | [
"Astronomy"
] | 851 | [
"Opticians",
"History of astronomy"
] |
67,618,180 | https://en.wikipedia.org/wiki/Hay%20hood | A hay hood is a roof extension which projects from the ridge of a barn roof, usually at the top of a gable. It provides shelter over a window or door used for passing hay into the attic or loft of the barn; it may hold a pulley for hoisting hay or hay bales up to the loft, or a fork or grapple and track system (or hay carrier) where hay can be lifted and then moved throughout the barn. A barn may have the ridge beam extended past the wall with a lifting mechanism but no hay hood.
This simplest hay hood includes a tapered roof extension providing some protection from the weather. A non-tapered extension provides more protection. A hay hood with partial or full walls underneath the extension on two sides is more protective, while an extension with three sides, allowing hay to be brought into the barn only through its "floor" keeps virtually all rain or snow out of the barn.
A hay hood can be built on a barn with any roof type. The type of hood is generally determined by the weather of a particular region. A barn in a semi-arid region may have no hood or just a simple pointed one. A barn in a region with frequent driving rain may have a completely enclosed hay hood. This is common in an area of western Oregon in the United States, centered on the town of Monroe in the Willamette Valley, where it is called a hay cupola. Most gambrel roofed barns in the western U.S. have pointed hay hoods. Hay hoods have been built on round barns.
It may also be known as a hay bonnet, hay gable, widow's peak, crow's beak, or hanging gable.
To prevent small gaps around the closed doors at the beam penetration that would allow birds to enter the barn, one farmer in Reasnor, Iowa, designed a hay hood with a "bunker door" that when closed, was an angled floor on the hay hood, completely enclosing the hood and keeping birds such as sparrows and pigeons out of the barn.
Other uses
A little catshead (alternatively cat's head or cats head) is an architectural feature commonly found on multi-storied mills, agricultural buildings, and factories, composed of a small extension protruding from the gable end of a larger roof.
A grist mill with a single main roof and catsheads at each end vaguely resembles a cat's head in sillohuette, with the catsheads forming the "ears" of the imaginary feline; this may be the origin of the name.
Catsheads originally existed to protect the ropes and pulleys associated with lifting equipment (such as the block and tackle rigs used to shift multi-ton milling equipment and the simple wheel pulleys used to lift fodder into haylofts) from ice and the corrosion caused by rain. In driest climates, if they had an opening to the building which lacked a door or window, this may have been adequate to prevent the goods from deteriorating.
Adding the protective catshead to the gable end of a roofline makes roofing tasks such as taking and removing tiles/panels simpler, and was an economy as obviates the flashing (weatherproofing) of a completely separate roof.
Whimsical architectural styles (such as New World Queen Anne Revival architecture) may also sport catsheads as non-functional decorative features.
Gallery
Notes
References
Architectural elements | Hay hood | [
"Technology",
"Engineering"
] | 698 | [
"Building engineering",
"Architectural elements",
"Components",
"Architecture"
] |
67,619,277 | https://en.wikipedia.org/wiki/Ethernet%20consist%20network | Ethernet Consist Network (ECN) is a train communication network based on Ethernet technology standardised with IEC-61375-3-. This is a vehicle (consist) communication like Multifunction Vehicle Bus (MVB) in train communication network (TCN).
ECN provides an Internet Protocol (IP) interface to TCMS (train control and management system) and other systems within a vehicle (consist).
The Ethernet technology's large bandwidth (typically 100 Mbit/s) is particularly suitable for data-intensive systems like video surveillance or passenger information systems.
See also
Ethernet Train Backbone (ETB)
References
External links
Industrial Ethernet
Network topology
Networking standards
Ethernet standards | Ethernet consist network | [
"Mathematics",
"Technology",
"Engineering"
] | 138 | [
"Networking standards",
"Network topology",
"Computer standards",
"Computer networks engineering",
"Topology",
"Industrial Ethernet"
] |
67,619,861 | https://en.wikipedia.org/wiki/TEOS-10 | TEOS-10 (Thermodynamic Equation of Seawater - 2010) is the international standard for the use and calculation of the thermodynamic properties of seawater, humid air and ice. It supersedes the former standard EOS-80 (Equation of State of Seawater 1980). TEOS-10 is used by oceanographers and climate scientists to calculate and model properties of the oceans such as heat content in an internationally comparable way.
History
TEOS-10 was developed by the SCOR(Scientific Committee on Oceanic Research)/IAPSO(International Association for the Physical Sciences of the Oceans) Working Group 127 which was chaired by Trevor McDougall. It has been approved as the official description of the thermodynamic properties of seawater, humid air and ice in 2009 by the Intergovernmental Oceanographic Commission (IOC) and in 2011 by the International Union of Geodesy and Geophysics (IUGG).
Physical basis
TEOS-10 is based on thermodynamic potentials. Fluids like humid air and liquid water in TEOS-10 are therefore described by the Helmholtz energy F(m,T,V)=F(m,T,m/ρ) or the specific Helmholtz-energy f(T,ρ)=F(m,T,m/ρ)/m. The Helmholtz energy has a unique value across phase boundaries. For the calculation of the thermodynamic properties of seawater and ice, TEOS-10 uses the specific Gibbs potential g(T,P)=G/m, G=F+pV, because the pressure is a more easily measurable property than density in a geophysical context. Gibbs energies are multivalued around phase boundaries and need to be defined for each phase separately.
The thermodynamic potential functions are determined by a set of adjustable parameters which are tuned to fit experimental data and theoretical laws of physics like the ideal gas equation. Since absolute energy and entropy cannot be directly measured, arbitrary reference states for liquid water, seawater and dry air in TEOS-10 are defined in a way that
internal energy and entropy of liquid water at the solid-liquid-gas triple point are zero,
entropy and enthalpy of seawater are zero at SA (Absolute Salinity) = 35.16504 g/kg, T (Temperature) = 273.15 K, p (pressure) = 101325 Pa,
entropy and enthalpy of dry air are zero at T (Temperature) = 273.15 K, p (pressure) = 101325 Pa.
Included thermodynamic properties
TEOS-10 covers all thermodynamic properties of liquid water, seawater, ice, water vapour and humid air within their particular ranges of validity as well as their mutual equilibrium composites such as sea ice or cloudy (wet and icy) air.
Additionally, TEOS-10 covers derived properties, for example the potential temperature and Conservative Temperature, the buoyancy frequency, the planetary vorticity and the Montgomery and Cunningham geostrophic streamfunctions. A complete list of featured properties can be found in the TEOS-10 Manual.
The handling of salinity was one of the novelties in TEOS-10. It defines the relationship between Reference Salinity and Practical Salinity, Chlorinity or Absolute Salinity and accounts for the different chemical compositions by adding a regionally variable 𝛿SA (see Figure). TEOS-10 is valid for Vienna Standard Mean Ocean Water which accounts for different hydrogen- and oxygen-isotope compositions in water which affects the triple point and therefore phase transitions of water.
Software packages
TEOS-10 includes the Gibbs Seawater (GSW) Oceanographic Toolbox which is available as open source software in MATLAB, Fortran, Python, C, C++, R, Julia and PHP. While TEOS-10 is generally expressed in basic SI-units, the GSW package uses input and output data in commonly used oceanographic units (such as g/kg for Absolute Salinity SA and dbar for pressure p).
In addition to the GSW Oceanographic Toolbox, the Seawater-Ice-Air (SIA) Library is available for Fortran and VBA (for the use in Excel), and covers the thermodynamic properties of seawater, ice and (moist) air. In contrast to the GSW Toolbox, the SIA-Library exclusively uses basic SI-units.
Differences between TEOS-10 and EOS-80
EOS-80 (Equation of State of Seawater -1980) uses Practical Salinity measured on the PSS-78 (Practical Salinity Scale of 1978) scale that itself is based on measurements of temperature, pressure and electrical conductivity. Thus, EOS-80 did not account for different chemical compositions of seawater.
EOS-80 consisted of separate equations for density, sound speed, freezing temperature and heat capacity but did not provide expressions for entropy or chemical potentials. Therefore, it was not a complete and consistent description of the thermodynamic properties of seawater. Inconsistencies in EOS-80 appear for example in the heat content at high pressure, depending on which equation is used for the calculation. Furthermore, EOS-80 was not consistent with meteorological equations while TEOS-10 is valid for humid air as well as for seawater.
EOS-80 provided expressions for potential temperature, which removes the effect of pressure on temperature but not for Conservative Temperature, which is a direct measure for potential enthalpy and therefore heat content.
In TEOS-10 the current standard for temperature scales, ITS-90 (International Temperature Scale of 1990) is used, while EOS-80 used the IPTS-68 (International Practical Temperature of 1968). In the SIA-Library of TEOS-10 implementations to convert outdated into current scales are included.
TEOS-10 was derived using absolute pressure P while EOS-80 used the pressure relative to the sea surface 𝑝sea. They can be converted by: P/Pa = 101325 + 10000 ∙ 𝑝sea/dbar (see Atmospheric Pressure).
External links
TEOS-10 Website
The Gibbs-Seawater (GSW) Oceanographic Toolbox functions
TEOS-10 Primer
TEOS-10 Manual
References
International standards
Thermodynamics | TEOS-10 | [
"Physics",
"Chemistry",
"Mathematics"
] | 1,326 | [
"Thermodynamics",
"Dynamical systems"
] |
67,620,089 | https://en.wikipedia.org/wiki/PG5%20%28molecule%29 | PG5 is the largest stable synthetic molecule ever made. PG5 was designed by the organic chemistry research group working at the Federal Institute of Technology in Zürich.
Properties
PG5 has a molecular mass of about 200 MDa or 200,000,000 g/mol. It has roughly 20 million atoms and a diameter of roughly 10 nm. Its length is up to a few micrometers. It is similar in size to a tobacco mosaic virus with comparable length and diameter. PG5 was shown to be resistant against attempts to flatten its structure.
References
Polymers
Dihydroxybenzoic acids
Amides
Dendrimers | PG5 (molecule) | [
"Chemistry",
"Materials_science"
] | 128 | [
"Functional groups",
"Dendrimers",
"Polymer chemistry",
"Polymers",
"Amides"
] |
67,623,165 | https://en.wikipedia.org/wiki/Julia%20Rozanska | Iulia Antonivna Rozhanska (; ; 1901 – 23 April 1967), also spelt Julia Różańska, was a Soviet topologist. After studying under Pavel Aleksandrov, she was an associate professor at Moscow State University. She was a member of the Moscow Mathematical Society. She attended the First International Topological Conference, Moscow, 1935.
Works
.
. The paper she presented at the Moscow Conference, 1935.
References
1901 births
1967 deaths
Topologists
Place of birth missing
Academic staff of Moscow State University
Soviet mathematicians
Soviet women mathematicians
Ukrainian women mathematicians | Julia Rozanska | [
"Mathematics"
] | 113 | [
"Topology stubs",
"Topologists",
"Topology"
] |
67,624,499 | https://en.wikipedia.org/wiki/Time%20in%20Abkhazia | Time in Abkhazia, a partially recognised state largely recognised by most countries as part of Georgia, is given by Moscow Standard Time (MST; UTC+03:00). Abkhazia does not observe daylight saving time.
As Abkhazia is not an internationally recognised sovereign state, it is not granted a zone.tab entry on the IANA time zone database.
See also
Time in Europe
Time in South Ossetia
List of time zones by country
List of time zones by UTC offset
References
External links
Current time in Abkhazia at Time.is
Time by country
Time in Europe
Geography of Abkhazia | Time in Abkhazia | [
"Physics"
] | 126 | [
"Spacetime",
"Physical quantities",
"Time",
"Time by country"
] |
67,626,151 | https://en.wikipedia.org/wiki/Oosporein | Oosporein is a toxic, bronze colored dibenzoquinone with the molecular formula C14H10O8. Oosporein was first extracted from various molds and has antibiotic, antiviral, cytotoxic, antifungal, and Insecticide properties.
References
Further reading
Mycotoxins | Oosporein | [
"Chemistry"
] | 71 | [
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
67,626,578 | https://en.wikipedia.org/wiki/QX39 | QX39 (Compound A, CA39) is a synthetic compound that activates chaperone-mediated autophagy (CMA) by increasing the expression of the lysosomal receptor for this pathway, LAMP2A lysosomes. It showed potent activity in vitro but has poor pharmacokinetic properties and was not suitable for animal research. Subsequent research led to the development of CA77.1, a CMA activator suitable for in vivo use.
References
Oxazines
Chloroarenes | QX39 | [
"Chemistry"
] | 110 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
67,628,319 | https://en.wikipedia.org/wiki/Cellular%20beam | Cellular beam is a further development of the traditional castellated beam. The advantage of the steel beam castellation process is that it increases strength without adding weight, making both versions an inexpensive solution to achieve maximum structural load capacity in building construction.
The difference between cellular beam and castellated beam is the visual characteristic. A cellular beam has round openings (circular pattern) while the castellated beam has hexagonal openings (hexagonal pattern), both of which are achieved by a cutting and welding process. Cellular beams are usually made of structural steel, but can also be made of other materials. The cellular beam is a structural element that mainly withstands structural load laterally applied to the axis of the beam, and influences the overall performance of steel framed buildings. The type of deflection is mainly done by bending.
Introduction
In 1987, Westok Structural Services Ltd of Wakefield invented and patented the structural steel cellular beam.
In 2009, the Steel Construction Institute developed software to assist engineers evaluating the dynamic behaviour of composite floors supported by cellular beams.
Since 1940, civil engineers have endeavoured to find solutions to reduce the cost and weight of steel frame construction. Due to the restrictions with regard to the maximum permissible deflections, the high-strength properties of structural steel cannot always be optimally used. As a result, several new steel mixtures have been identified to increase the stiffness of steel components without significantly increasing the required steel weight. The use of steel girders with web openings (SBWOs) for structures such as industrial buildings has proven to be extensive. Civil engineers came up with a solution to use a composite design of ultra-shallow floor joists together with concrete used on the Douala Grand Mall in Cameroon. Since the 2010s, further investigations into steel construction and fire protection have been carried out, which led to innovations in the field of passive fire protection that could save lives and assets.
See also
Castellated beam
Open web steel joist
Steel design
Weld access hole
References
Structural engineering
Structural steel | Cellular beam | [
"Engineering"
] | 409 | [
"Structural engineering",
"Civil engineering",
"Structural steel",
"Construction"
] |
67,628,503 | https://en.wikipedia.org/wiki/Komei%20Fukuda | Komei Fukuda (, born 1951) is a Japanese mathematician known for his contributions to optimization,
polyhedral computation and oriented matroid theory. Fukuda is a professor in optimization and computational geometry
in the Department of Mathematics and in the Institute of Theoretical Computer Science at ETH Zurich.
Education and career
Fukuda studied administration engineering at Keio University, graduating in 1974 and earning a master's degree in 1976. He began doctoral work in the same field, but in 1976 transferred to the University of Waterloo to their PhD program in combinatorics and optimization. He completed his PhD in 1982, with Jack Edmonds as his doctoral advisor.
After completing his PhD, he returned to Japan as an assistant professor at the Tokyo Institute of Technology. He moved to the University of Tsukuba as an associate professor in 1989. After visiting the École Polytechnique Fédérale de Lausanne and ETH Zurich in 1993–1994 and 1995–1996 respectively, as an invited professor, he took a joint position as a professor in the departments of mathematics at both universities in 1996. He also held a tenured professorship at McGill University in 2002–2003. In 2008 he gave up his position at the École Polytechnique Fédérale de Lausanne, becoming affiliated only with ETH Zurich, and since 2012 he has held a joint appointment in mathematics and computer science at ETH Zurich.
Contributions
Fukuda has studied finite pivot algorithms in various settings, including linear programming,
linear complementarity and their combinatorial abstractions in oriented matroids.
With Tamás Terlaky, Fukuda worked on a particular class of pivot algorithms, known as
the criss-cross method.
With David Avis, Fukuda proposed a reverse-search algorithm for the
vertex enumeration problem; their algorithm generates all of the vertices of a convex polytope or, dually, of an arrangement of hyperplanes.
Selected publications
References
External links
Home page at ETH Zurich
1951 births
Living people
Combinatorialists
Researchers in geometric algorithms
Keio University alumni
University of Waterloo alumni
Academic staff of Tokyo Institute of Technology
Academic staff of the University of Tsukuba
Academic staff of ETH Zurich
20th-century Japanese mathematicians
21st-century Japanese mathematicians | Komei Fukuda | [
"Mathematics"
] | 453 | [
"Combinatorialists",
"Combinatorics"
] |
67,628,525 | https://en.wikipedia.org/wiki/1-Nonene | 1-Nonene is particular structural isomer of nonene where the double bond is located at the primary, or alpha, position making it a linear alpha olefin. It is used in the production of surfactants and lubricants, usually by way of nonylphenol. Its more branched analogue, tripropylene, is also used in this way.
References
Alkenes | 1-Nonene | [
"Chemistry"
] | 83 | [
"Organic compounds",
"Alkenes"
] |
73,417,008 | https://en.wikipedia.org/wiki/Enbezotinib | Enbezotinib (TPX-0046) is an experimental anticancer medication which acts as a RET inhibitor, as well as an inhibitor of SRC kinase.
See also
Pralsetinib
Rebecsinib
Resigratinib
Selpercatinib
Zeteletinib
References
Enzyme inhibitors
Experimental drugs | Enbezotinib | [
"Chemistry"
] | 73 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
73,418,221 | https://en.wikipedia.org/wiki/Propionigenium | Propionigenium is a genus of bacteria in the family Tissierellales.
See also
List of bacteria genera
List of bacterial orders
References
Fusobacteriota
Taxa described in 1983 | Propionigenium | [
"Biology"
] | 40 | [
"Bacteria stubs",
"Bacteria"
] |
73,418,856 | https://en.wikipedia.org/wiki/Osmium%28II%29%20chloride | Osmium(II) chloride or osmium dichloride is an inorganic compound composed of osmium metal and chlorine with the chemical formula .
Synthesis
Osmium(II) chloride can be prepared by disproportionation of osmium(III) chloride at 500 °C in vacuum.
Physical properties
Osmium(II) chloride is a hygroscopic dark brown solid that is insoluble in water.
It is soluble in ethanol and ether.
Chemical properties
Osmium(II) chloride does not react with hydrochloric acid and sulfuric acid.
It reacts with CO at 220 °C:
Uses
Osmium(II) chloride can be used for the catalytic production of trialkylamines.
References
Osmium compounds
Chlorides
Platinum group halides | Osmium(II) chloride | [
"Chemistry"
] | 158 | [
"Chlorides",
"Inorganic compounds",
"Salts"
] |
73,419,158 | https://en.wikipedia.org/wiki/Osmium%20octafluoride | Osmium octafluoride is an inorganic chemical compound of osmium metal and fluorine with the chemical formula . Some sources consider it to be a still hypothetical compound. An early report of the synthesis of was much later shown to be a mistaken identification of . Theoretical analysis indicates would have an approximately square antiprismatic molecular geometry.
Potential synthesis
Rapid cooling of fluorine and osmium reaction products:
References
Osmium compounds
Fluorides
Metal halides
Hypothetical chemical compounds | Osmium octafluoride | [
"Chemistry"
] | 98 | [
"Inorganic compounds",
"Hypotheses in chemistry",
"Salts",
"Inorganic compound stubs",
"Theoretical chemistry",
"Metal halides",
"Hypothetical chemical compounds",
"Fluorides"
] |
73,420,346 | https://en.wikipedia.org/wiki/Concrete%20frame | A concrete frame, also known as a concrete skeleton, is a structure composed of interconnected beams, columns, and slabs that is used to support larger structures. Due to the low cost of producing them, concrete frames are often used when building damns, bridges, and buildings. Reinforced concrete frame structures are commonly used when making concrete frames, as steel rebar's stronger tensile strength makes up for concretes tensile weakness.
Concept
Connected by rigid joints, reinforced concrete frames consist of beams and columns. With the beams and columns cast in a single operation to act in unison, reinforced concrete frames provide resistance to lateral loads and gravity due to the bends in the beams and columns. Common subtypes of this frame include: Nonductile reinforced concrete frames with or without infill walls, ductile reinforced concrete frames with or without infill walls, and nonductile reinforced concrete frames with reinforced infill walls.
Masonry infills
Most prevalent type are these: RC frames with concrete infill walls, commonly referred to as dual systems, are typically used in earthquake prone areas like Turkey, Colombia, and Greece.
Advantages
While being the most fire resistant material around, concrete frames are stronger, safer, less costly, and more energy efficient than steel buildings.
See also
Steel frame
Reinforced concrete
Framing (construction)
References
Reinforced Concrete Frame Sector. https://www.citb.co.uk/media/aycpantr/rc-skills-pathway-schools-brochure.pdf
Yakut Ahmet. Reinforced Concrete Frame Construction. Retrieved 3/20/23. https://www.world-housing.net/wp-content/uploads/2011/06/RC-Frame_Yakut.pdf
Bertagnoli, Gabriele. (2016). Reinforced Concrete Frame Structures. Procedia Engineering, 161, 1013–1017. https://doi.org/10.1016/j.proeng.2016.08.841
Concrete | Concrete frame | [
"Engineering"
] | 417 | [
"Structural engineering",
"Concrete"
] |
73,421,000 | https://en.wikipedia.org/wiki/Polymeridium%20neuwirthii | Polymeridium neuwirthii is a species of corticolous (bark-dwelling) lichen in the family Trypetheliaceae. Found in Venezuela, it was formally described as a new species in 2014 by Dutch lichenologist André Aptroot. This lichen has a pinkish-grey thallus that does not fluoresce under ultraviolet light. P. neuwirthii is similar to Polymeridium quinqueseptatum but can be differentiated by its with large oil droplets and consistently 7-septate, rough . The ascomata are 0.4–0.6 mm in diameter, with a spherical that is and solitary. The ostiole is apical, and the contains large oil droplets. There are eight ascospores per ascus, which are iodine-negative, 7-septate, and measure 30–33 by 9–10 μm. The ascospore wall is roughly ornamented. No chemical substances have been detected in this lichen. The type specimen was collected in Puerto Ayacucho, Venezuela, on a twig of a shrub. The species is named in honour of the collector of the type and only specimen, Gerhard Neuwirth.
References
neuwirthii
Lichen species
Lichens described in 2013
Lichens of Venezuela
Taxa named by André Aptroot
Species known from a single specimen | Polymeridium neuwirthii | [
"Biology"
] | 286 | [
"Individual organisms",
"Species known from a single specimen"
] |
73,421,071 | https://en.wikipedia.org/wiki/Pertusaria%20archeri | Pertusaria archeri is a rare species of corticolous (bark-dwelling), crustose lichen in the family Pertusariaceae. Found in Thailand, it was formally described as a new species in 2005 by Sureeporn Jariangprasert. The type specimen was collected by the author from Doi Khun Tan National Park (Lamphun-Lampang provinces) at an altitude of , where it was found in an evergreen forest growing on the bark of Styrax. The species epithet honours Australian lichenologist Alan W. Archer, an authority of Pertusaria taxonomy. The main distinguishing characteristics of Pertusaria archeri are its two-spored asci, and the presence of depside methyl esters as lichen products.
See also
List of Pertusaria species
References
archeri
Lichen species
Lichens described in 2005
Lichens of Indo-China
Species known from a single specimen | Pertusaria archeri | [
"Biology"
] | 191 | [
"Individual organisms",
"Species known from a single specimen"
] |
73,421,105 | https://en.wikipedia.org/wiki/Pertusaria%20bokluensis | Pertusaria bokluensis is a rare species of corticolous (bark-dwelling), crustose lichen in the family Pertusariaceae. Found in Thailand, it was formally described as a new species in 2005 by Sureeporn Jariangprasert. The type specimen was collected from the Bo Kluea Nhuea community (Bo Kluea district) at an altitude of , where it was found growing on the bark of Dalbergia. It is only known from the type specimen. The species epithet combines the name of the type locality with the Latin adjective -ensis, meaning "place of origin". The main distinguishing characteristics of Pertusaria bokluensis are the eight-spored asci, and the presence of the lichen products 4,5-dichlorolichexanthone and 2,2'-di-O-methylstenosporic acid.
See also
List of Pertusaria species
References
bokluensis
Lichen species
Lichens described in 2005
Lichens of Indo-China
Species known from a single specimen | Pertusaria bokluensis | [
"Biology"
] | 227 | [
"Individual organisms",
"Species known from a single specimen"
] |
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