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74,025,176 | https://en.wikipedia.org/wiki/Haworthiopsis%20%C3%97%20lisbonensis | Haworthiopsis × lisbonensis, formerly Haworthia lisbonensis, is an ornamental succulent plant, considered a hybrid of unknown parentage.
History
Haworthiopsis × lisbonensis is named after Lisbon, as the original plant was discovered by António Gomes Amaral in the collection of the Botanical Garden of the University of Lisbon. Gomes Amaral brought it to the attention of Flávio Resende, a Portuguese botanist, who described it as Haworthia lisbonensis in 1946. It has since been moved to the genus Haworthiopsis, and it is currently considered a hybrid, rather than a true species.
Flávio Resende shared living material with several of his correspondents around the world, and the plant is still found in cultivation.
References
lisbonensis
Hybrid plants | Haworthiopsis × lisbonensis | [
"Biology"
] | 162 | [
"Hybrid plants",
"Plants",
"Hybrid organisms"
] |
74,025,383 | https://en.wikipedia.org/wiki/Haldane%27s%20sieve | Haldane's sieve is a concept in population genetics named after the British geneticist J. B. S. Haldane. It refers to the fact that dominant advantageous alleles are more likely to fix in the population than recessive alleles. Haldane's sieve is particularly relevant in situations where the effects of natural selection are strong and the beneficial mutations have a significant impact on an organism's fitness.
According to Haldane's sieve, when a new advantageous mutation arises in a population, it initially occurs as a single copy (a de novo mutation), borne by an heterozygous individual.
This way, genetic dominance is important to estimate the fate of new mutations, that is, if new mutations are going to fix or go extinct.
Dominant alleles are more readily exposed to directional selection since the moment they are rare, and thus they are more likely to fix as a result of a "hard sweep".
The term "sieve" in Haldane's sieve metaphorically represents this filtering effect of natural selection.
When adaptation stems from the species pool of standing genetic variation, a "soft sweep", the rationale does not apply, because the allele is no longer rare in the beginning of the sweep. In fact, recessive alleles are more likely to sweep than dominant sweeps when alleles are previously maintained in the population.
Limited dispersal and population structure can reduce the effects of Haldane's sieve. In subdivided populations, limited dispersal increases inbreeding and homozygosity, allowing recessive alleles to express their beneficial effects more frequently and thus accelerate their fixation. This effect is most pronounced when dispersal is strongly limited (e.g., ).
Haldane's sieve has important implications for understanding the dynamics of adaptation and evolution in diploid populations. It highlights the role of natural selection in driving genetic changes in the presence of genetic dominance.
See also
Population genetics
Selective sweep
Natural selection
Adaptive evolution
References
Population genetics
Genetics concepts
Classical genetics
Selection
Evolutionary processes
Evolutionary biology | Haldane's sieve | [
"Biology"
] | 423 | [
"Evolutionary biology",
"Evolutionary processes",
"Selection",
"Genetics concepts"
] |
74,025,450 | https://en.wikipedia.org/wiki/Trevor%20Lawley | Trevor Lawley FMedSci is a Faculty member and Senior Group Leader in the Host-Microbiota Interactions Lab at the Wellcome Sanger Institute (WSI). He is also co-founder and Chief Scientific Officer of the biotech company Microbiotica.
During his career, Lawley has pioneered the application of high throughput genomic and culturing approaches to characterise enteric pathogens and investigate the microbiomes contained on and within host organisms, during periods of health and disease.
Education and career
Lawley received his bachelor's degree in Biology in 1997 from Acadia University. He then studied for a PhD at the University of Alberta, in the laboratories of Diane Taylor and Laura Frost, where he studied the mechanisms that pathogenic bacteria use to disseminate antibiotic resistance genes. After his PhD, Trevor was awarded a Canadian Institutes of Health Research post-doctoral fellowship to work in the Laboratories of Stanley Falkow and Denise Monack at Stanford University, where he studied the impact of antibiotic treatment on Salmonella disease and transmission.
In 2007 Lawley received a Royal Society of London Award to start a research programme on Clostridioides difficile disease and transmission at the Wellcome Sanger Institute. In 2010, he was appointed as a Career Development Fellow in the Sanger Institute Faculty and was promoted to Faculty Group Leader in 2014 and a Senior Group Leader in 2021. Lawley chairs the Wellcome Sanger Institute International Fellows programme, which focuses on empowering scientists from Low- and Middle-Income Countries through access to cutting-edge genomic technologies and training.
In December 2016, Lawley, together with Gordon Dougan and Mike Romanos, co-founded the biotech company Microbiotica through £12M seed funding from Cambridge Innovation Capital, IP Group and Seventure. Microbiotica develops Live Biotherapeutic Products, biomarkers and microbiome-based technologies focused on autoimmune diseases and cancers. In 2018, Microbiotica entered into a collaboration with Genentech to discover, develop and commercialise inflammatory bowel disease (IBD)biomarkers, targets and medicines. In 2020, Microbiotica entered into a partnership with Cambridge University Hospitals and Cancer Research UK to discover and develop biomarkers and medicines for cancer immunotherapy patients with melanoma, renal cell carcinoma or lung cancer. In March 2022, Microbiotica secured Series B funding to perform two phase 1 clinical studies for treatment of patients with melanoma (MELODY-1, NCT06540391) or ulcerative colitis (COMPOSER-1, NCT06582264). The two clinical trials started in 2024 and clinical readouts are expected in Q2 2026.
Research
Lawley leads the Host-Microbiota Interactions Lab at the Sanger Institute, which explores the relationship between humans and the bacteria and viruses that collectively form their microbiome.
Lawley and his team use a range of methods and tools, including large scale metagenomic analysis, genetics, mouse and cellular models, state-of-the art microbial culturing, transcriptomics, proteomics and machine learning, to investigate the microbial communities associated with human health and a range of developmental disorders, diseases and poorly understood syndromes. They have a particular interest the roles of the microbiome in infectious disease, autoimmune disease, cancer and childhood developmental disorders. Their work has pioneered concepts, analytical tools and methodologies that, through data- and hypothesis-driven approaches, have led to foundational discoveries and enabled translation of medicines and diagnostics from the human microbiome.
Lawley and his team overturned the "great plate count anomaly dogma", long held in microbial ecology, by demonstrating the majority of the human gut microbiota is culturable. This breakthrough involved bacterial culturing, biobanking and genome sequencing at scale, leading to the development of fast, affordable, yet sophisticated, high-resolution gut microbiome analysis.. A major outcome of biobanking pure cultures has been experimental testing of biological hypotheses derived from metagenomic analysis, which moves the field towards studies of causation and enables the realisation of microbiome derived medicines.
They focus on several key areas including:
Characterising the evolution of taxonomic and functional diversity in the human microbiome.
Investigating the early-life microbiome, and how birth-mode and clinical interventions, impact microbiome acquisition and assembly.
Understanding host-microbiome interactions and drivers of inflammatory disease and cancer.
Studying the fundamental biology, transmission and pathogenesis of C. difficile.
Lawley’s group has authored over 100 papers. Their work is regularly covered in the scientific and popular press.
Awards and honours
Lawley was elected as a Fellow of the Academy of Medical Sciences in 2023. In 2015 Lawley received the Peggy Lillis Foundation “Innovator Award” for Pioneering Work on Live Biotherapeutics.
References
Year of birth missing (living people)
Living people
Canadian microbiologists
Wellcome Trust
Biotechnologists
Acadia University alumni
University of Alberta alumni
Stanford University staff
Fellows of the Academy of Medical Sciences (United Kingdom)
Canadian geneticists | Trevor Lawley | [
"Biology"
] | 1,076 | [
"Biotechnologists"
] |
74,026,151 | https://en.wikipedia.org/wiki/Molybdenum%20oxytetrafluoride | Molybdenum oxytetrafluoride is the inorganic compound with the formula MoOF4. It is a white, diamagnetic solid. According to X-ray crystallography, it is a coordination polymer consisting of a linear chain of alternating Mo and F atoms. Each Mo center is octahedral, the coordination sphere being defined by oxide, three terminal fluorides, and two bridging fluorides. In contrast to this motif, tungsten oxytetrafluoride crystallizes as a tetramer, again with bridging fluoride ligands.
Reactions
The acetonitrile adduct of molybdenum oxytetrafluoride can be prepared by treating molybdenum hexafluoride with hexamethyldisiloxane in acetonitrile:
Molybdenum oxytetrafluoride is susceptible to hydrolysis to give molybdenum difluoride dioxide.
References
Metal halides
Molybdenum(VI) compounds
Oxyfluorides
Coordination polymers | Molybdenum oxytetrafluoride | [
"Chemistry"
] | 230 | [
"Inorganic compounds",
"Metal halides",
"Salts"
] |
74,026,474 | https://en.wikipedia.org/wiki/Fostering%20%28falconry%29 | Fostering, in falconry and reintroduction of birds, is a method of breeding birds for their introduction into the wild that consists of placing chicks in the nest of a couple that has others of a similar age and size. Sometimes it can also be used when the chicks have already left the nest but continue to be fed by their parents.
This method can be used in those species that do not have siblicide behaviors and that are capable of carrying out this adoption without rejecting the new chicks. In addition, the parents must have previously been assessed to find out if they are capable of feeding more chicks.
See also
Cross-fostering
Hack (falconry)
Hand-rearing
Human-guided migration
Puppet-rearing
References
Falconry
Animal reintroduction
Conservation biology | Fostering (falconry) | [
"Biology"
] | 156 | [
"Conservation biology"
] |
74,027,431 | https://en.wikipedia.org/wiki/Marcel%20Froissart | Marcel Froissart (20 December 1934, 6th arrondissement of Paris – 21 October 2015, 14th arrondissement of Paris) was a French theoretical physicist, specializing in particle physics. He is known for the Froissart bound and the Froissart–Stora equation.
Biography
After secondary study at the Lycée Louis-le-Grand, Marcel Froissart matriculated in 1953 at the École polytechnique, where he graduated in 1955. He then entered in October 1956 Mines ParisTech, now known as École nationale supérieure des mines de Paris (Mines Paris - PSL). After completing only one semester of a four-semester technical curriculum, he was sent in civil cooperation with the French Navy to Algeria (during the Algerian War, which lasted from 1954 to 1962). He was reassigned in 1957 to the Commissariat à l'énergie atomique (CEA), for which he worked in Geneva from 1957 to 1958 at CERN. Again in civil cooperation with the French military, he was reassigned to work at the University of Algeria from 1958 to 1959. He completed his study at Mines ParisTech in 1959. He held a temporary appointment from 1960 to 1961 at the University of California, Berkeley, where he worked on S-matrix theory under the leadership of Geoffrey Chew and collaborated with, among others, Marvin "Murph" Goldberger and Kenneth M. Watson. At Princeton University, he held temporary positions for the academic years 1961–1962 and 1965–1966. In the 1960s, he collaborated with the mathematician Bernard Morin.
In 1964 Froissart received the Prix Paul Langevin awarded by the Société Française de Physique (SFP) . He contributed to the 13th International Conference on High-Energy Physics held in Berkeley from the 1st of August to the 7th of September 1966. In January 1967 his paper with John R. Taylor was published. In October 1967 in Brussels, Froissart was an invited participant at the 14th Solvay Conference. In 1973 he was appointed a professor at the Collège de France in the particle physics chair, which he held until he retired as professor emeritus in 2004.
Froissart consolidated into a single laboratory, dependent on his professorial chair, two laboratories — one headed by Francis Perrin and the other by Louis Leprince-Ringuet. At the time of the consolidation, those laboratories were the two largest of the Collège de France. The immediate task was to unify those two laboratories, whose members generally considered the two as competing organizations. A longer-term task was to reduce the size of the laboratory, while maintaining significant activity on the international scene. At the consolidated laboratory, the policy followed by the Collège de France was to only host small, easily mobile units — in case that the professor directing the consolidated laboratory was replaced by a new director pursuing different research goals in physics. Thus, in the consolidated laboratory, the physicists who wanted to work on the LHC, which was not to enter service until after the departure of Professor Froissart, were jointly requested by the Institut national de physique nucléaire et de physique des particules (IN2P3) and the Collège de France to leave the consolidated laboratory and to join LHC-oriened laboratories. Of those researchers who remained in the consolidated laboratory, a majority turned to research on astroparticles (to be in line with Froissart's expertise and leadership in high energy physics). The laboratory then took the name Physique corpusculaire et cosmologie (PCC). When Marcel Froissart retired, the laboratory formed the core of the new Astroparticle and Cosmology Laboratory (APC, AstroParticule et Cosmologie), created in 2006 by Pierre Binétruy. The new laboratory had researchers from Paris Diderot University (Paris 7), the Observatoire de Paris and the Commissariat à l'énergie atomique (CEA).
Froissart, as laboratory director, found himself at the center of a controversy over the rubbiatron. He was one of the main developers of the Groupement des scientifiques pour l'information sur l'énergie nucléaire (GSIEN, Association of Scientists for Information on Nuclear Energy).
The famous photographer Martine Franck made a portrait of Froissart. Marcel Froissart was a grandson of the glassmaker and a nephew of , who was in the 1930s one of the designers of the wooden construction technique called froissartage.
Upon his death in 2015, Marcel Froissart was survived by his widow, 3 sons, 2 daughters, and 10 grandchildren.
Selected research achievements
Study of the polarization stability of polarized relativistic protons in a synchrotron, showing the existence of resonance energies leading to polarization reversal
Work on the theory of particle collisions, within the framework of the Mandelstam representation
Research of a possible axiomatic justification of the Mandelstam representation
Generalization of Bell's inequalities to various systems
Research on the application of the theory of analytic functions to the localization of a point on a plane surface (Patent 1988)
Studies of various properties of light mesons
Selected publications
Texts on line
1970 : Modèles théoriques, basse énergie, Le Journal de physique, vol. 31, no. C5 (novembre-décembre), pp. C5-88
1974 - 2004 : Cours publics et rapports de Marcel Froissart, Collège de France (Chaire de physique corpusculaire)
Patent
1988 : A device for two-dimensional localization of current-generating events on a resistive surface, U.S. patent US4788384A (in collaboration with Roger Bruère-Dawson, Bernard M. Maréchal et Marcio N. DeSouza)
References
1934 births
2015 deaths
20th-century French physicists
21st-century French physicists
French theoretical physicists
Particle physicists
French astrophysicists
Lycée Louis-le-Grand alumni
École Polytechnique alumni
ParisTech alumni
Academic staff of the Collège de France
People associated with CERN | Marcel Froissart | [
"Physics"
] | 1,288 | [
"Particle physicists",
"Particle physics"
] |
74,028,272 | https://en.wikipedia.org/wiki/Puppet-rearing | Puppet-rearing is a method of breeding birds in captivity for their reintroduction into the wild that consists of feeding chicks with puppets that simulate adults of their species to avoid direct contact with humans.
Through imprinting, birds associate the first care images with their parents. In artificial incubation of eggs or orphaned chicks it is necessary to feed them by hand as long as they cannot do it themselves. For this reason, puppets are used to guarantee that the birds can be released later, having generated links with their own species and remaining distrustful of the human being.
See also
Artificial incubation
Cross-fostering
Fostering (falconry)
Hack (falconry)
Hand-rearing
Human-guided migration
Falconry
References
Falconry
Animal reintroduction
Conservation biology | Puppet-rearing | [
"Biology"
] | 156 | [
"Conservation biology"
] |
74,028,513 | https://en.wikipedia.org/wiki/Symphytum%20peregrinum | Symphytum peregrinum may refer to the following comfrey species:
Symphytum peregrinum auct.: Symphytum × uplandicum, the Russian or Quaker comfrey
Symphytum peregrinum Ledeb.: Symphytum officinale subsp. officinale
References | Symphytum peregrinum | [
"Biology"
] | 69 | [
"Set index articles on plants",
"Set index articles on organisms",
"Plants"
] |
74,029,102 | https://en.wikipedia.org/wiki/Action%20tendency | Action tendency is a psychological term in behavioral science which refers to an individual's urge to carry out a particular behavior, particularly as a component of emotion. In behavioral science, an individual's emotions direct their response to current circumstances or relationships; thus, the action tendency, as a constituent factor of the individual's overall emotional response, is a temporary and immediate impulse.
Cognitive Scope
Action tendency is the motivational component of emotional decision making which is responsible for the preparation and direction of motor responses. Under the emotional framework, motivation can be thought of as the state of readiness to engage in a certain action with the goal of achieving a desired result. The action tendency is distinct from cognitive, physiological, and expressive components, which likewise determine an individual's behavior.
Because action tendency is, essentially, an immediate suggestion for a response in a particular set of circumstances, it is informed by an individual's set of preferences at the current point in time, which are supplied elsewhere within the emotion. Action tendency, therefore, changes as an individual moves between emotional states, and is modified by the individual's present cognitive and physiological abilities.
Conditioning
Several theories and experiments support the notion that action tendencies can be primed to produce a desired result before the onset of emotion. In 2010, an experiment which trained addicts to either approach or avoid alcohol found that the subjects' action tendency towards alcohol was positively affected in accordance with the training condition.
Perceived action tendency may also play a role in social conditioning and self-esteem which is observable at an early developmental stage. In 1979, experimental data demonstrated that children who self-reported more frequent tendencies towards assertiveness and aggression experienced poor self-image and negative social stigma. These findings suggest that the observation of behavioral tendencies by oneself or others plays a significant role in the construction of identity.
See also
Determination
References
Social sciences terminology
Motivation
Behavioral concepts | Action tendency | [
"Biology"
] | 379 | [
"Behavior",
"Behavioral concepts",
"Motivation",
"Behaviorism",
"Ethology",
"Human behavior"
] |
74,029,187 | https://en.wikipedia.org/wiki/Sohini%20Kar-Narayan | Sohini Kar-Narayan is a British–Indian materials scientist, professor at the University of Cambridge and the editor-in-chief of the journal APL Electronic Devices, published by the American Institute of Physics. Her research considers polymer based materials for energy harvesting. She was awarded the 2023 Royal Society of Chemistry Peter Day Prize.
Early life and education
Kar-Narayan was born and raised in Nigeria before moving to India to earn her undergraduate degree at the Presidency University, Kolkata. She was a graduate student at the Indian Institute of Science. After earning her doctorate in 2009, she moved to the University of Cambridge, where she was awarded a Dorothy Hodgkin Fellowship.
Research and career
Kar-Narayan was made a lecturer at the University of Cambridge in 2015, and then a professor in 2018. Her research considers the development of nanomaterials for sensing, biomedical applications and energy. She was awarded a European Research Council Starting Grant to develop piezoelectric nanogenerators.
In 2022, Kar-Narayan was awarded the Armourers and Brasiers' Venture Prize for ArtioSense, a smart sensor that can help orthopaedic surgeons provide personalised care following surgical implants. Kar-Narayan developed microfluidic force sensors that facilitate soft tissue balance and help to precisely place implants. She created the sensor in partnership with surgeons, recognising that they needed to complement the surgical process without changing the workflow.
Awards and honours
2015 World Economic Forum Young Scientist Award
2021 Top 50 Influential Women in Engineering
2022 Armourers and Brasiers' Venture Prize
2022 Elected Fellow of the Institute of Materials, Minerals and Mining
2023 Royal Society of Chemistry Peter Day Prize
2023 European Research Council Consolidator Grant
2024 AFM and SPM Award, Royal Microscopical Society
2024 Innovator of the Year, Women Leaders in Electronics awards (Electronics Weekly)
2024 Elected a fellow of the Royal Academy of Engineering
Selected publications
References
Living people
Year of birth missing (living people)
Presidency University, Kolkata alumni
Indian Institute of Science alumni
Academics of the University of Cambridge
Indian emigrants to the United Kingdom
Women materials scientists and engineers
Indian materials scientists
21st-century British women scientists
21st-century Indian women scientists
British materials scientists
21st-century British scientists
21st-century Indian scientists
Fellows of the Institute of Materials, Minerals and Mining
Fellows of the Royal Academy of Engineering
Female fellows of the Royal Academy of Engineering | Sohini Kar-Narayan | [
"Materials_science",
"Technology"
] | 495 | [
"Women materials scientists and engineers",
"Materials scientists and engineers",
"Women in science and technology"
] |
74,030,115 | https://en.wikipedia.org/wiki/Strobilurus%20trullisatus | Strobilurus trullisatus is a species of agaric fungus in the family Physalacriaceae. It is native to the Pacific Northwest, where it grows on Douglas-fir cones.
Description
The fruiting bodies of S. trullisatus grow in clusters on the cones of the Douglas-Fir. They feature a thin, white cap ranging from wide. It has gills that are adnate to adnexed, close, and white to pinkish-tan. The stipe ranges from with a diameter ranging from .
References
Physalacriaceae
Fungi described in 1916
Fungi of North America
Strobilurins
Taxa named by William Alphonso Murrill
Fungus species | Strobilurus trullisatus | [
"Biology"
] | 143 | [
"Fungi",
"Fungus species"
] |
74,030,194 | https://en.wikipedia.org/wiki/High%20explosive%20violent%20reaction | A high explosive violent reaction (HEVR) includes reactions ranging from a fast deflagration of the high explosive (HE), up to and including a detonation of the high explosive. The explosive wave may be subsonic or supersonic.
Discussion
In the mid-1990s, scientists and engineers working at the United States Department of Energy's National Security Laboratories began applying Probabilistic Risk Assessment methodologies to understand and enhance nuclear-weapon-safety over a life cycle. Probabilistic Risk Assessment (PRA) generally address three basic questions:
What can go wrong, or what are the initiators or initiating events (undesirable starting events) that lead to adverse consequence(s) (e.g., a nuclear-weapon accident, incident or off-normal event)?
What and how severe are the potential detriments, or the adverse consequences from the initiating event?
What is the likelihood of these adverse consequences, or what are the probabilities or frequencies of occurrence?
Addressing questions two and three required weapon-scientists and engineers to develop methods and terminologies to estimate and describe warhead-response to abnormal environments (e.g., identified initiating events) with a focus on the potential for release or dispersal of special nuclear material (SNM). Nuclear yield from abnormal environments was not part of the PRA focus because all of the United States' nuclear weapons are required to adhere to strict one-point-safety standards. To describe PRA warhead-response possibilities, weaponeers categorized SNM dispersal outcomes into three possible categories:
Mechanical dispersal due to breach of the pit (localized scatter with no aerosolization);
Combustion dispersal due to burning of the HE and SNM (approximately 0.1% aerosolization); and
HEVR dispersal defined as an explosion or "violent" reaction that outside of a laboratory or test-range environment can only be described as a continuum from violent deflagration to detonation (assumed 100% aerosolization).
Since the advent of applying PRA methodologies to nuclear-weapon safety in the mid-1990s, the term HEVR has gained wide usage among scientists and engineers working in the fields of explosive science, safety, and surety.
References
Explosives
Nuclear weapon safety
External links
Related topical areas
National Security Laboratories - NNSA Nuclear Security Enterprise
DOE Nuclear Weapons Safety and Surety
Plutonium pit production | High explosive violent reaction | [
"Chemistry"
] | 491 | [
"Explosives",
"Explosions"
] |
74,030,200 | https://en.wikipedia.org/wiki/Non-invertible%20symmetry | In physics, a non-invertible symmetry is a symmetry of a quantum field theory that is not described by a group, and which in particular does not have an inverse.
Non-invertible symmetries were first studied in 2-dimensional conformal field theory, where fusion categories govern the fusion rules, rather than a group.
Four-dimensional examples of non-invertible symmetries can be obtained from Maxwell theory with topological theta term, via a combination of its SL(2,Z) duality and a discrete subgroup of its electric or magnetic 1-form symmetry.
References
External links
"A New Kind of Symmetry Shakes Up Physics" by Kevin Hartnett, Quanta Magazine
"Non-Invertible Symmetries and their Representations", video lecture by Sahand Seifnashri at Institute for Advanced Study
Quantum field theory
Quantum mechanics
Mathematical physics | Non-invertible symmetry | [
"Physics",
"Mathematics"
] | 178 | [
"Quantum field theory",
"Applied mathematics",
"Theoretical physics",
"Quantum mechanics",
"Theoretical physics stubs",
"Mathematical physics"
] |
74,030,853 | https://en.wikipedia.org/wiki/Radium%20iodate | Radium iodate is an inorganic compound, a salt of radium and iodic acid with the chemical formula .
Synthesis
Radium iodate is obtained by the reaction of a soluble radium salt and potassium iodate:
Physical properties
Radium iodate forms colorless crystals. It is poorly soluble in water.
References
Iodates
Radium compounds | Radium iodate | [
"Chemistry"
] | 70 | [
"Iodates",
"Oxidizing agents"
] |
74,031,057 | https://en.wikipedia.org/wiki/David%20M.%20Post | David M. Post is a research scientist and academic administrator. He is currently a professor of Ecology and Evolutionary Biology at Yale University and the Vice President (Academic Affairs)., Dean of Faculty, and Visiting Wong Ngit Liong Professor at Yale-NUS College, the first liberal arts college in Singapore. Post is an aquatic ecologist who studies food webs, evolution, and stable isotopes in lakes and rivers in Connecticut and Kenya.
He obtained his B.S. in Wildlife Ecology in 1992 and his M.S. in zoology in 1996 from University of Wisconsin-Madison, and his Ph.D. in Ecology and Evolutionary Biology from Cornell University in 2000.
Academic career
Post's academic career at Yale University began in 2002 as assistant professor at the Department of Ecology and Evolutionary Biology. He was promoted to associate professor in 2008 and full Professor in 2014. During his tenure at Yale University, he served as the Director of Graduate Studies for E&EB (2010–2013), Chair of the University Wide Committee on Sexual Misconduct (2014–2018), Chair of the Head of college review committee for Timothy Dwight College (2019–2020) and chair, Natural Science Subcommittee of the Off-Campus Research and Fieldwork Review Committee (COVID oversight) (2020–2021).
He became Dean of Faculty at Yale-NUS College in 2021 and Vice President (Academic Affairs) in 2022. As part of the college's senior leadership team, Post oversees all academic programming within the college with a key focus on sustaining its curriculum, enabling faculty and student research, and encouraging student and faculty development. His priorities include maintaining excellence in teaching and research, supporting faculty, mentoring, and developing areas of distinction among the divisions and majors.
Research
Post's research tests long-standing questions about food web structure and dynamics, the influence of environmental change on community structure and ecosystem function, spatial linkages among ecosystems, and the importance of interactions between ecology and evolution for community and ecosystem processes.
Post is known for his work on food-chain length and development and application of stable isotopes methods. His recent work has explored the implications of intraspecific variation and rapid evolution for ecological communities and ecosystems; and the role of widlife in moving organic matter among ecosystems in the Maasai Mara, Kenya
In 2014, The New York Times featured his study on alewives in Connecticut lakes where he is tracking the outcome of the species' restoration at Rogers Lake. One of his notable research was the study in 2017 on how the annual mass drownings of Serengeti wildebeest can have positive impacts on the Mara River ecosystem.
Awards and honours
Post received the R.H. Whittaker Award for outstanding oral presentation and Cole Award for outstanding publication from the Department of Ecology and Evolutionary Biology, Annual Symposium, Cornell University.
He earned the 2002 Raymond L. Lindeman Award from the Association for the Sciences of Limnology and Oceonography for his 2000 publication "Ecosystem size determines food-chain length in lakes" and the 2003 IRPE Prize for publishing uniquely independent, original and/or challenging research representing an important scientific breakthrough at a young age (<40 years).
Post was elected a Fellow of the American Association for the Advancement of Science (AAAS) in 2019 and a member of The Connecticut Academy of Science and Engineering in 2020.
Notable publications
Source:
Post, D.M., M.L. Pace, and N.G. Hairston Jr. 2000. Ecosystem size determines food-chain length in lakes. Nature 405:1047–1049. doi: 10.1038/35016565
Post, D.M., M.E. Conners, and D.S. Goldberg. 2000. Prey preference by a top predator and the stability of linked food chains. Ecology 81:8–14. doi: 10.1890/0012- 9658(2000)081[0008:PPBATP]2.0.CO;2
Post, D.M. 2002. Using stable isotopes to estimate trophic position: models, methods, and assumptions. Ecology, 83:703-718. doi: 10.1890/0012-9658(2002)083[0703:USITET]2.0.CO;2
Post, D.M. 2003. Individual variation in the timing of ontogenetic niche shifts in largemouth bass. Ecology 84:1298–1310. doi:10.1890/0012-9658(2003)084[1298:IVITTO]2.0.CO;2
Post, D.M., D.A. Arrington, C.A. Layman, G. Takimoto, J. Quattrochi, and C. G. Montaña. 2007. Getting to the fat of the matter: models, methods and assumptions for dealing with lipids in stable isotope analyses. Oecologia 152:179–189. doi:10.1007/s00442-006-0630-x
Post, D.M., E.P. Palkovacs, E.G. Schielke, and S.I. Dodson. 2008. Intraspecific phenotypic variation in a predator affects zooplankton community structure and cascading trophic interactions. Ecology 89:2019–2032. doi:10.1890/07-1216.1
Post, D.M., and E.P. Palkovacs. 2009. Eco-evolutionary feedbacks in community and ecosystem ecology: interactions between the ecological theater and the evolutionary play. Philosophical Transactions of the Royal Society B 364: 1629–1640.
Sabo, J.L., J.C. Finlay, T. Kennedy, and D.M. Post. 2010. The role of discharge variation in scaling of drainage area and food chain length in rivers. Science 330:965–967. doi:10.1126/science.1196005
Walsh, M.R., DeLong, J.P., Hanley, T.C., and D.M. Post. 2012. A cascade of evolutionary change alters consumer-resource dynamics and ecosystem function. Proc. R. Soc. B. 279:3184–3192 doi:10.1098/rspb.2012.0496
Subalusky, A.L., C.L. Dutton, E.J. Rosi-Marshall, and D.M. Post. 2015. The Hippopotamus conveyor belt: vectors of carbon and nutrients from terrestrial grasslands to aquatic systems in sub-Saharan Africa. Freshwater Biology 60:512–525. doi:10.1111/fwb.12474
Subalusky, A.L. C.L. Dutton, E.J. Rosi, and D.M. Post. 2017. Annual mass drownings of the Serengeti wildebeest migration influence nutrient cycling and storage in the Mara River. Proceedings of the National Academy of Sciences 114:7647–7652. Doi:10.1073/pnas.1614778114
Des Roches, S., D.M. Post, N.E. Turley, J.K. Bailey, A.P. Hendry, M.T. Kinnison, J.A. Schweitzer,E.P. Palkovacs. 2018. Ecological effects of intraspecific variation. Nature Ecology and Evolution 2:57–64. Doi:10.1038/s41559-017-0402-5
Subalusky, A.L., and D.M. Post. 2019. Context dependency of animal resource subsidies. Biological Reviews 94:517–538. doi:10.1111/brv.
References
Yale_University_faculty
Academic staff of Yale-NUS College
Year of birth missing (living people)
Living people
American evolutionary biologists
American ecologists
American limnologists
Ecologists
Cornell University alumni
University_of_Wisconsin–Madison_alumni
Fellows_of_the_American_Association_for_the_Advancement_of_Science | David M. Post | [
"Environmental_science"
] | 1,699 | [
"Ecologists",
"Environmental scientists"
] |
74,031,801 | https://en.wikipedia.org/wiki/Thymic%20mimetic%20cells | Thymic mimetic cells are a heterogeneous population of cells located in the thymus that exhibit phenotypes of a wide variety of differentiated peripheral cells. They arise from medullary thymic epithelial cells (mTECs) and also function in negative selection of self-reactive T cells.
History
Some subsets of these cells were observed as early as the mid-1800s because of their distinct, seemingly misplaced, phenotype. The most readily observed subsets were those accumulating and forming microscopic structures, most notably Hassall's corpuscles resembling skin keratinocytes. Many subsets with a more dispersed distribution were found later. Substantial progress has been made in recent years owing to the rapid development of single cell sequencing methods, such as scRNA-seq or scATAC-seq.
Diversity
Although thymic mimetic cells exhibit transcriptional programmes of cells from other tissues, they are not identical to them and share a part of their gene expression with mTECs from which they arise. The entire range of phenotypes as well as the pathways that lead to them are still in need of further research. A recent review recognizes (based on expression of lineage specific transcription factors and cell products) the following subtypes: Basal (skin/lung) mTEC, Enterocyte/hepatocyte mTEC, Ciliated mTEC, Ionocyte mTEC, Keratinocyte mTEC, Microfold mTEC, Muscle mTEC, Neuroendocrine mTEC, Parathyroid mTEC, Secretory mTEC, Thyroid mTEC, Tuft mTEC.
Function
Since its discovery in 2001, AIRE (Autoimmune regulator) has been the main focus of studies of thymic (central) immune tolerance. AIRE induces the expression of many antigens specific to differentiated cells not found in the thymus (termed peripheral tissue antigens or tissue restricted antigens) thus helping to detect and remove T cells that react with these antigens. The mechanism of AIRE is complicated and there are reasons to believe that it is not the sole mechanism of TRA (tissue restricted antigen) expression. AIRE is not sequence specific making its action stochastic and not well targeted, TRAs can also be detected in cells with AIRE knocked out and patients with AIRE deficiency (APS-1) share some autoimmune symptoms but can have other symptoms which are not shared by most.
The expression of peripheral antigens in mimetic cells strongly implies a function in establishing central immune tolerance. This has been reported but further studies are needed. It is unknown what prompts the mTECs to differentiate into mimetic cells, the lineage specific transcription factors could be induced by AIRE or perhaps other signals. Lineage specific transcription factors expressed by some mimetic cell subtypes have been associated with autoimmune disorders.
In addition, some mimetic cells can shape the environment and function of the thymus by producing cytokines.
References
Immunology
Immune system
Thymus
Epithelial cells | Thymic mimetic cells | [
"Biology"
] | 636 | [
"Organ systems",
"Immunology",
"Immune system"
] |
74,032,572 | https://en.wikipedia.org/wiki/Molybdenum%20difluoride%20dioxide | Molybdenum difluoride dioxide is the inorganic compound with the formula MoF2O2. It is a white, diamagnetic, volatile solid.
Structure
Gaseous molybdenum difluoride dioxide is a tetrahedral molecule. According to X-ray crystallography, the solid is a coordination polymer consisting of trigonal primatic chains of made by linking monomers. The fluoride and oxide positions are disordered. A similar motif is adopted by titanium tetrafluoride.
Synthesis and reactions
The compound can be obtained by thermal decomposition of the dioxotetrafluoride, which in turn is obtained from sodium molybdate:
Heating sodium dioxotetrafluoride to 400 °C gives monomeric difluoride dioxide, which polymerizes upon condensation:
The compound also arises by hydrolysis of molybdenum oxytetrafluoride:
The compound dissolves in dimethylformamide to give a bis(adduct):
Further reading
References
Metal halides
Molybdenum(VI) compounds
Oxyfluorides | Molybdenum difluoride dioxide | [
"Chemistry"
] | 235 | [
"Inorganic compounds",
"Metal halides",
"Salts"
] |
74,033,110 | https://en.wikipedia.org/wiki/Kim%20Guldstrand%20Larsen | Kim Guldstrand Larsen R (born 1957) is a Danish scientist and professor of computer science at Aalborg University, Denmark. His field of research includes modeling, validation and verification, performance analysis, and synthesing of real-time, embedded, and cyber-physical systems utilizing and contributing to concurrency theory and model checking. Within this domain, he has been instrumental in the invention and continuous development of one of the most widely used verification tools, and has received several awards and honors for his work.
Education
Larsen has an MSc in mathematics from Aalborg University, 1982. In 1986, he received his PhD in Computer Science from University of Edinburgh, advised by Robin Milner.
Career
Since 1993, Larsen has been a professor in Computer Science at Aalborg Universitet. He has also been a visiting professor at several places around the world, including the National Institute for Research in Digital Science and Technology (INRIA) (as an international chair 2016-2020).
Larsen heads the Center for Embedded Software Systems (CISS). From 2007 to 2011, he was director of the university-industry consortium Danish Network of Embedded Systems (DaNES), and from 2011 to 2017, he was the Danish co-lead of the Danish-Chinese Center for IDEA4CPS: Foundations for Cyber-Physical Systems, established by the and the Natural Science Foundation of China (NSFC).
In addition, he was director of the Danish ICT Innovation Network (InfinIT) from 2009 to 2020, director of the Center for Data-Intensive Cyber-Physical Systems (DiCyPS) funded by from 2015 to 2021, and head of project on the Learning, Analysis, Synthesis, and Optimization of Cyber-Physical Systems (LASSO) project from 2015 to 2020, funded by an ERC Advanced Grant.
Larsen is one of the key figures behind the award-winning tool UPPAAL, which is one of the most widely used tools for the verification of real-time models. "UPPAAL in a Nutshell," written by Larsen and colleagues, is one of the most cited papers in The Journal Software Tools for Technology Transfer, published by Springer (citation rank in the 99th percentile).
He is a member of Royal Danish Academy of Sciences and Letters and elected fellow and digital expert (vismand) in the . He has served as the national expert for the Information and Communication Technology theme under the EU's 7th Framework Programme (FP7-ICT), and currently he is a member of the Digital, Industry, and Space referencegroup that serves the Danish Ministry of Higher Education and Science in connection to the EU Horizon Europe program.
Awards and honors (selected)
Honorary Doctor (Honoris causa), Uppsala University, 1999
Honorary Doctor (Honoris causa), École normale supérieure Paris-Saclay (formerly École normale supérieure de Cachan), Paris, 2007
Thomson Scientific Award as the most cited Danish computer scientist 1990-2004
Knight of the Order of the Dannebrog, 2007
Member of Academia Europaea
CAV Award 2013
ERC Advanced Grant, 2015
2016
Foreign Expert of China, Distinguished Professor, Northeastern University, 2018
Villum Investigator 2021 (30 M DKK) from Villum Foundation
CONCUR Test of Time award 2022
Selected works
Larsen has published six books (monographs) and more than 400 peer-reviewed papers and he has been cited many times (Google Scholar Citation Tracker). Selected works:
UPPAAL in a Nutshell, 1997
References
External links
Profile at Aalborg University
UPPAAL an integrated tool environment for modeling, validation and verification of real-time systems modeled as networks of timed automata
Living people
1957 births
Danish computer scientists
Software engineering
Formal methods
Automata (computation)
Embedded systems
Real-time computing
Systems theory
Concurrency (computer science)
Model checkers
Aalborg University alumni
Members of the Royal Danish Academy of Sciences and Letters | Kim Guldstrand Larsen | [
"Mathematics",
"Technology",
"Engineering"
] | 793 | [
"Systems engineering",
"Real-time computing",
"Computer engineering",
"Embedded systems",
"Computer systems",
"Model checkers",
"Software engineering",
"Computer science",
"Information technology",
"Formal methods",
"Mathematical software"
] |
74,033,193 | https://en.wikipedia.org/wiki/Abietatriene | Abietatriene is a diterpene, C20H30, that is abietane having three double bonds located at the positions 8, 11, and 13. It has a role as a plant metabolite and derives from a hydride of an abietane.
References
Diterpenes | Abietatriene | [
"Chemistry"
] | 69 | [
"Pharmacology",
"Medicinal chemistry stubs",
"Organic compounds",
"Pharmacology stubs",
"Organic compound stubs",
"Organic chemistry stubs"
] |
74,035,291 | https://en.wikipedia.org/wiki/Markov%20operator | In probability theory and ergodic theory, a Markov operator is an operator on a certain function space that conserves the mass (the so-called Markov property). If the underlying measurable space is topologically sufficiently rich enough, then the Markov operator admits a kernel representation. Markov operators can be linear or non-linear. Closely related to Markov operators is the Markov semigroup.
The definition of Markov operators is not entirely consistent in the literature. Markov operators are named after the Russian mathematician Andrey Markov.
Definitions
Markov operator
Let be a measurable space and a set of real, measurable functions .
A linear operator on is a Markov operator if the following is true
maps bounded, measurable function on bounded, measurable functions.
Let be the constant function , then holds. (conservation of mass / Markov property)
If then . (conservation of positivity)
Alternative definitions
Some authors define the operators on the Lp spaces as and replace the first condition (bounded, measurable functions on such) with the property
Markov semigroup
Let be a family of Markov operators defined on the set of bounded, measurables function on . Then is a Markov semigroup when the following is true
.
for all .
There exist a σ-finite measure on that is invariant under , that means for all bounded, positive and measurable functions and every the following holds
.
Dual semigroup
Each Markov semigroup induces a dual semigroup through
If is invariant under then .
Infinitesimal generator of the semigroup
Let be a family of bounded, linear Markov operators on the Hilbert space , where is an invariant measure. The infinitesimal generator of the Markov semigroup is defined as
and the domain is the -space of all such functions where this limit exists and is in again.
The carré du champ operator measuers how far is from being a derivation.
Kernel representation of a Markov operator
A Markov operator has a kernel representation
with respect to some probability kernel , if the underlying measurable space has the following sufficient topological properties:
Each probability measure can be decomposed as , where is the projection onto the first component and is a probability kernel.
There exist a countable family that generates the σ-algebra .
If one defines now a σ-finite measure on then it is possible to prove that ever Markov operator admits such a kernel representation with respect to .
Literature
References
Probability theory
Ergodic theory
Linear operators | Markov operator | [
"Mathematics"
] | 502 | [
"Functions and mappings",
"Mathematical objects",
"Linear operators",
"Ergodic theory",
"Mathematical relations",
"Dynamical systems"
] |
74,036,252 | https://en.wikipedia.org/wiki/Daniela%20Blanco | Daniela Blanco is a Venezuelan-born chemical engineer and co-founder and CEO of Sunthetics. Sunthetics is a sustainable materials startup company that is seeking to move the chemical industry away from its reliance on fossil fuels, such as gas and oil. Sunthetics focuses on electrochemical processes and utilizes its own proprietary Artificial Intelligence software to increase the efficiency of reactions that are powered using electricity. These chemical reactions are driven by "complex pulses of electrical current" using renewable energy as opposed to the traditional method requiring heat, which is dependent on the use of fossil fuels. In 2020, Blanco was named a Top Innovator under 35 in Latin America by MIT Technology Review.
Early life and education
Blanco initially wanted to study medicine after high school and become a neurosurgeon. However, she decided against this path after witnessing a surgery during a vocational internship and having a negative reaction to the sight of blood. She chose to pursue chemical engineering after shadowing a chemical engineer at a Venezuelan chemical company.
Blanco earned her bachelor's degree in chemical engineering from Universidad Simón Bolívar in Venezuela.
She moved to the United States in 2017 to attend New York University. Blanco has discussed initially feeling "so behind and so out of place" at NYU because, due to a lack of funding, the university she previously attended in Venezuela didn't have the up-to-date laboratory equipment and technology that the NYU research labs had.
Blanco earned her PhD in chemical engineering from New York University in 2020.
Career and contributions
Blanco has received numerous prizes throughout her career so far, including the following: the $100,000 Technology Venture Prize at the NYU Stern $300K Entrepreneurship Challenge, the $20,000 top prize in the InnoVention Competition at Tandon, a $20,000 Stage II VentureWell grant, the title of 2019 Global Student Entrepreneur of the Year, and the Lemelson-MIT Student Prize in 2020.
Blanco was featured in the 2021 documentary Own the Room co-directed by Cristina Costantini and Darren Foster. The film follows five student entrepreneurs competing in the 2019 Global Student Entrepreneur Awards with the finals taking place in Macau, China. Blanco, representing the United States, won the title of Global Champion with its accompanying $100,000 grand prize.
Blanco has contributed to research papers, including these:
Sunthetics
Blanco co-founded Sunthetics, along with fellow NYU graduate, Myriam Sbeiti, and NYU professor of Chemical and Biomolecular Engineering, Miguel Modestino.
The idea for Sunthetics was born while Blanco was a PhD student at NYU working on her PhD thesis. Her goal was to find a way to efficiently power chemical reactions using electricity rather than heat which relies on the burning of fossil fuels. She was initially focused on applying this idea to part of the development process for the widely used material, nylon. When faced with a lack of interest from Nylon manufacturing companies, the Sunthetic's co-founders decided to pivot their companies focus to the Artificial Intelligence (AI) algorithms behind the process. The AI tools that had been developed were the key to making the renewable energy driven chemical reactions as efficient as possible. Blanco also found there was significantly more interest in the AI technology she and the Sunthetics team had developed and it was this technology that could be applied to many different industries. Sunthetics now focuses on further developing and perfecting that AI-driven machine learning platform. As of 2022, Sunthetics has six employees.
Recognition
2021, Forbes 30 Under 30 on its Energy list
2020, MIT Technology Review award for Top Innovator under 35 in Latin America
2019, Global Champion at Global Student Entrepreneur Awards
2019, named Brightest AI-CI Mind by the MIT Center for Collective Intelligence
Personal life
Blanco was raised in Venezuela by her mother, Maria Eugenia Blanco.
She credits her resiliency and motivation, in part, to her Venezuelan upbringing stating: "...Venezuelans are always incredibly optimistic. They focus on what is going right. They laugh at the things that are not going so well."
Blanco credits a science experiment she witnessed during her preschool class as being the source of her initial inspiration to become a scientist.
She currently lives in Temple, Texas.
References
Living people
New York University alumni
Venezuelan engineers
Chemical engineers
Hispanic and Latino American scientists
Hispanic and Latino American women scientists
American technology company founders
American women company founders
21st-century women scientists
Year of birth missing (living people)
21st-century American women scientists | Daniela Blanco | [
"Chemistry",
"Engineering"
] | 903 | [
"Chemical engineering",
"Chemical engineers"
] |
74,037,011 | https://en.wikipedia.org/wiki/Tsippy%20Tamiri | Tsippy Tamiri (1952 – 2017) was an Israeli mass spectrometrist, specialized in the analysis of explosives, drugs, and poisons.
Early life and education
Tsippy Tamiri grew up in Rishon LeZion. She enlisted in the Israel Defense Forces at eighteen. After discharge, she obtained a bachelor's degree in pharmacy from the Hebrew University of Jerusalem. She received a master's degree in chemistry from the Hebrew University of Jerusalem and a PhD in chemistry from Technion – Israel Institute of Technology.
Career
Tamiri worked at the forensic laboratory of the Israel Police, where she was the head of the mass spectrometry department. She conducted research in the analysis of explosives, drugs and poisons. She published on the preparation, characterization, and analysis of urea nitrate.
Tamiri served as the president of the Israeli Society of Mass Spectrometry. She served on the organizing committee of the second Middle Eastern and Mediterranean Sea Region Countries Mass Spectrometry – MASSA 2013 Workshop in 2013.
Selected publications
Book chapter
Analysis of Explosives by Mass Spectrometry, Tsippy Tamiri and Shmuel Zitrin, in Forensic Investigation of Explosions, A. Beveridge (Ed), 2011.
GC/MS Analysis of PETN and NG in Post-Explosion Residues, T. Tamiri, S. Zitrin, S. Abramovich-Bar, Y. Bamberger and J. Sterling, in Advances in Analysis and Detection of Explosives, J. Yinon (Ed), 1993.
Awards
Tamiri received the Yehuda Yinon Award in 2011.
References
Mass spectrometrists
Hebrew University of Jerusalem alumni
Technion – Israel Institute of Technology alumni
Israeli women scientists
Forensic scientists | Tsippy Tamiri | [
"Physics",
"Chemistry"
] | 361 | [
"Biochemists",
"Mass spectrometry",
"Spectrum (physical sciences)",
"Mass spectrometrists"
] |
74,037,099 | https://en.wikipedia.org/wiki/Mariagrazia%20Pizza | Mariagrazia Pizza is an Italian vaccine researcher who is a professor at Imperial College London. She worked as Senior Scientific Director for Bacterial Vaccines at GSK plc. She was involved with the development of the first pertussis vaccine. In 2023, she was awarded the IVI-SK bioscience Park MahnHoon Award.
Early life and education
Pizza was born in Eboli, Italy and lived there until 1980. She studied chemistry and pharmaceutical science at the University of Naples Federico II. Her dissertation used nuclear magnetic resonance to explore the structure of opioid peptides. When a family member became ill, she decided to learn more about pharmaceutical design. She moved to the European Molecular Biology Laboratory in Heidelberg, where she learnt molecular biology and engineering.
Research and career
Pizza has focused on the design and development of new vaccines. In 1986, she joined Sclavo, a vaccine research centre in Siena. She spent six years there, contributing to the development of the first pertussis vaccine, which was able to protect infants, and was safer and more immuno-active than other pertussis vaccines on the market. Sclavo was sold to Chiron, which was eventually acquired by Novartis. Motivated by their success and advances in whole genome sequencing, Pizza started working on a Meningococcal vaccine. She joined GSK plc in 2016.
In 2023, Pizza joined the faculty at Imperial College London. She is an Honorary Visiting Professor at the University of Leicester.
Awards and honours
2000 Elected a member of the European Molecular Biology Organization (EMBO)
2018 Elected a Member of the Academia Europaea (MAE)
2023 IVI-SK bioscience Park MahnHoon Award
Selected publications
Personal life
Pizza has two children.
References
Year of birth missing (living people)
Living people
Vaccinologists
20th-century Italian women scientists
20th-century Italian scientists
21st-century Italian women scientists
21st-century Italian scientists
People from Eboli
GSK plc people
University of Naples Federico II alumni
Academics of Imperial College London
Members of the European Molecular Biology Organization
Members of Academia Europaea | Mariagrazia Pizza | [
"Biology"
] | 427 | [
"Vaccination",
"Vaccinologists"
] |
72,602,031 | https://en.wikipedia.org/wiki/List%20of%20Argentine%20provinces%20and%20territories%20by%20life%20expectancy | This is a list of provinces of Argentina by life expectancy. Life expectancy is the average number of years of age that a group of infants born in the same year can expect to live, if maintained, from birth. The data is from a 2020 report by the Pacific Disaster Center.
Life expectancy in 2018
See also
List of South American countries by life expectancy
References
Ranked lists of country subdivisions
Argentina | List of Argentine provinces and territories by life expectancy | [
"Biology"
] | 83 | [
"Senescence",
"Life expectancy"
] |
72,603,954 | https://en.wikipedia.org/wiki/Penicillium%20tealii | Penicillium tealii is a species of fungus in the genus Penicillium. It was discovered at Rowlands Creek near Uki in far northeastern New South Wales in April 2021 on the body of a dead spider. Citizen scientist Donovan Teal accidentally discovered the fungus while collecting samples of insect-eating fungi and it was subsequently named after him.
See also
List of Penicillium species
References
tealii
Fungi described in 2022
Fungus species
Fungi of Australia | Penicillium tealii | [
"Biology"
] | 97 | [
"Fungi",
"Fungus species"
] |
72,604,342 | https://en.wikipedia.org/wiki/Harold%20Herzlich%20Distinguished%20Technology%20Achievement%20Medal | The Harold Herzlich Distinguished Technology Achievement Medal is an award conferred that recognizes "innovators, who through persistence and dedication, have advanced a paradigm shift in tire manufacturing, tire reliability or performance". It is awarded as a part of the biennial ITEC tire show. Prior to 2012, it had been known by the name ITEC Distinguished Technology Achievement Award.
Recipients
2012 - Marion Pottinger
2014 - Bernhard Blümich
2016 - Andreas Limper
2018 - Steven M. Cron
2020 - Walter H. Waddell
2022 - William V. Mars
2024 - Brendan Rogers
References
Tire industry
Tire industry people | Harold Herzlich Distinguished Technology Achievement Medal | [
"Technology"
] | 126 | [
"Science and technology awards",
"Science award stubs"
] |
72,605,515 | https://en.wikipedia.org/wiki/Sara%20Garc%C3%ADa%20Alonso | Sara García Alonso (born 1989) is a Spanish cancer researcher and reserve ESA astronaut. Since 2019, she has been a postdoctoral researcher at the Spanish National Cancer Research Centre. In 2022, she was chosen as a reserve astronaut in the European Astronaut Corps.
Education and academic career
García attended University of León, where she earned a bachelor's degree in biotechnology in 2012 and a master's degree in biomedical and biological research in 2013.
As a doctoral candidate at University of Salamanca, García conducted research on cancer medicine as a university research assistant for the Spanish National Research Council. She earned a doctorate cum laude in the nuclear biology of cancer and translational medicine in the university's in 2018, advised by Atanasio Pandiella Alonso. Her doctoral dissertation focused on mechanisms of resistance to antibody-drug conjugates in ErbB receptors and it won her the university's Outstanding Doctorate Award the following year.
Since 2019, she has been working as a postdoctoral researcher on drug discovery and experimental oncology at the Spanish National Cancer Research Centre, where she has led a project to discover drugs for lung cancer and pancreatic cancer in the laboratory of Mariano Barbacid. Her research has focused on RAF1 selective degraders as a therapeutic target, in order to combat certain forms of cancers. She participated in a 6-month training programme at IE Business School, in Madrid, in 2021. She has volunteered for the , a nonprofit organisation.
Astronaut career
The European Space Agency (ESA) selected García as a reserve astronaut for the 2022 selection of astronauts of the European Astronaut Corps. García and fellow astronaut candidate Pablo Álvarez Fernández, both natives of León, Spain, are the first Spaniards selected by the ESA since Pedro Duque joined the European Astronaut Corps in 1992. They were selected from more than 22,500 candidates across Europe. As a reserve astronaut, García will continue her current job, and will begin training if found to be an ideal candidate for a future space mission.
Personal life
García was born in León, Spain, in 1989. In addition to her biomedical research, she has worked as a personal trainer and a nutrition coach.
Notes
References
Living people
1989 births
21st-century Spanish scientists
21st-century Spanish women
21st-century Spanish women scientists
People from León, Spain
Cancer researchers
Spanish biologists
Molecular biologists
Spanish astronauts
Women astronauts
University of Salamanca alumni
European Space Agency personnel
Spanish women academics
Women molecular biologists | Sara García Alonso | [
"Chemistry"
] | 485 | [
"Biochemists",
"Molecular biology",
"Molecular biologists"
] |
72,605,704 | https://en.wikipedia.org/wiki/AZ%20Cygni | AZ Cygni (BD+45 3349) is a large red supergiant (M3 Iab) in the constellation of Cygnus. Located 2,090 parsecs (6,800 ly) from Earth, it has been studied by the CHARA array in order to understand the surface variations of red supergiants.
Observation history
AZ Cygni first observed in the observations used to produce the Bonner Durchmusterung catalogue, published by Friedrich Argelander in the mid 19th century. Thomas William Backhouse showed that BD +45°3349 (the 19th century name for AZ Cygni) is a variable star, based on observations from 1894 to 1904. It was given the variable star designation AZ Cygni, in 1912. It has since then been included in many star surveys and catalogues, including the Two-Micron Sky Survey, 2MASS, Tycho-2 Catalogue and Gaia (DR2 and DR3).
From 2011 to 2016, it was observed using the Michigan Infra-Red Combiner (MIRC) at the six-telescope Center for High Angular Resolution Astronomy Array (CHARA array) to investigate the evolution of surface features on red supergiants. These observations were used to derive the fundamental stellar parameters of the star, reconstruct images of the star and test models of 3D radiative hydrodynamics in red supergiants.
Physical parameters
Luminosity
The Gaia DR2 catalogue estimated AZ Cygni's absolute bolometric magnitude at , corresponding to a luminosity of approximately . Although the distance is potentially unreliable due to a very high amount of astrometric noise, rated at a significance of 47.4, anything above a rating of 2 is 'probably significant'.
A paper in 2019 calculated the luminosity of AZ Cygni using the Gaia distance and a bolometric magnitude of -7.58, which would result in a luminosity of around . Another paper in 2019 estimated three luminosity values of , and with an average of . According to a 2021 paper, the best fitting atmosphere models would correspond to luminosities of , and .
Radius
The radius of AZ Cygni was first determined to be around in a 2019 paper based on the Gaia-derived distance, although it is potentially unreliable due to a high amount of astrometric noise.
By using the angular diameter and Gaia parallax-derived distance in the 2019 Mid-infrared stellar Diameters and Fluxes compilation Catalogue (MDFC), a radius between and can be derived. Another paper in 2019 estimated five different radii from observations between 2011 and 2016 based on the MDFC angular diameter and Gaia parallax: (2011), (2012), (2014), (2015) and (2016). The same paper also approximated AZ Cygni's radius based on model spectra, in which three values of , and were estimated with an average of .
The radius of AZ Cygni was again estimated at based on its angular diameter and Gaia parallax in a 2021 study. A separate paper in 2021 calculated a radius of , an average value after using the star's angular diameter and Gaia parallaxes. Based on the best fitting atmosphere models, three different radii were calculated: , and .
Temperature and spectral type
In a 1989 paper it was estimated that AZ Cygni would have spectral types of between M2Iab and M4Iab. A study in 2000 estimated that the spectral type of AZ Cygni is M3.1Iab. The spectral type of AZ Cygni was estimated at M3 Iab in a 2002 paper.
A paper in 2004 estimated that the effective temperature of AZ Cygni is 3,200 K with a spectral type of M3 Iab. AZ Cygni had 3 different effective temperature estimates in a paper in 2019 derived from model spectra: 4,000 K, 4,100 K and 3,867 K with an average of K. In another study in 2021 AZ Cygni would have three effective temperature estimates based on the best fitting atmosphere models: 4,000 K, 4,000 K and 3,972 K and also mentions that it is an M2–4.5 Iab star. The RSG and Close Stars Catalog (2024) features an adopted mean spectral type of M3 for AZ Cygni based on previous spectral types.
Mass
The mass of AZ Cygni was first determined based on the best fitting model spectra, which would correspond to three mass estimates: , and with an average of . A paper in 2021 estimated three mass estimates equal to based on the best fitting atmosphere models.
Surface features
AZ Cygni has a complex surface, with large and small features that vary over different timescales. Patterns of large convection cells, varying over periods of more than a year, are combined with smaller hot granules of rising gas that vary over shorter timescales. The size of the larger surface features is in line with models of 3D radiative hydrodynamics in red supergiants.
Notes
See also
References
M-type supergiants
Cygnus (constellation)
Cygni, AZ
TIC objects
J20575942+4628004
Semiregular variable stars
Durchmusterung objects | AZ Cygni | [
"Astronomy"
] | 1,077 | [
"Cygnus (constellation)",
"Constellations"
] |
72,605,768 | https://en.wikipedia.org/wiki/Aeroclub%20Barcelona-Sabadell | Aeroclub Barcelona-Sabadell is a major aeroclub founded in 1953, as a result of the union of two aviation clubs in Catalonia, Barcelona and Sabadell. The AeroClub Barcelona Sabadell carries out its activities at the Sabadell Airport (Barcelona) at the La Cerdaña Aerodrome (Gerona) and at the Seo de Urgell Airport (Lleida). Although it is at the Sabadell Airport where its headquarters are located, and where most of the activity of powered flight takes place.
Fleet
AeroClub Barcelona-Sabadell fleet is made up of a total of 43 aircraft: 27 single-engine aircraft, 4 multi-engine aircraft, 3 helicopters, 3 aerobatic aircraft and 6 gliders.
See also
Aero Club Milano
Letalski center Maribor
Flying club
External links
Aeroclub Barcelona-Sabadell web page
Facebook
References
Flying clubs
Organizations established in 1953
Civil aviation in Spain
Flight training
Aviation schools
Aircraft maintenance
Organisations based in Barcelona
1953 establishments in Catalonia | Aeroclub Barcelona-Sabadell | [
"Engineering"
] | 208 | [
"Aircraft maintenance",
"Aerospace engineering"
] |
72,606,747 | https://en.wikipedia.org/wiki/International%20Bathymetric%20Chart%20of%20the%20Southern%20Ocean | The International Bathymetric Chart of the Southern Ocean (IBCSO) is a regional mapping initiative of the General Bathymetric Chart of the Oceans (GEBCO). IBSCO receives support from the Nippon Foundation – GEBCO Seabed 2030 Project.
Background
IBCSO is a joint project by the International Hydrographic Organization, the Scientific Committee on Antarctic Research, the General Bathymetric Chart of the Oceans and the Seabed 2030 Project. The project aims to identify and pool all Bathymetry data in the Southern Ocean and use that data to produce gridded bathymetric maps of the seafloor.
The extent of the project is bound by 50°S, stretching from the southern tip of South America to the coastal waters of Antarctica. The IBCSO project is currently hosted by the bathymetry department at the Alfred Wegener Institute for Polar and Marine Research in Bremerhaven.
Description
Bathymetric data from all data holders are reviewed and pooled at 1 meter resolution to form the basis of the bathymetric data set. This includes all seafloor mapping sources from modern echo sounding methods such as multibeam echosounders and singlebeam echosounders to historic lead line measurements. A weighted blockmedian filter is run across the pooled data set to create a spatial map of high and low quality data.
The low quality data is processed using a spline interpolation algorithm and used as a background layer. The high quality data from e.g. modern multibeam echosounder data is then added on top and incorporated in the background surface using a bending algorithm. Regions with no data coverage are padded by bathymetric data from the dataset collected by the Shuttle Radar Topography Mission.
The gridded product is made available to the public at a 500m x 500m resolution in a polar stereographic projection (EPSG: 9354) with either bedrock data of the Antarctic continent based on BedMachine and data for the ice surface topography derived from various sources such as REMA. The most recent version is also incorporated into the annual release of the General Bathymetric Chart of the Oceans grid.
The first version of IBCSO was published in 2013, covering the Southern Ocean south of 60°S. More than 4,200 million ocean soundings of diverse types and quality were incorporated.
IBCSO became associated with and is supported by the Nippon Foundation – Seabed 2030 Project since 2017. IBCSO version 2 was published in 2022 and increased the extent of the bathymetric map to 50°S, increasing the area covered by 2.5 compared to IBCSO version 1. 92.7% of map data originate from multibeam data, 6.7% originate from singlebeam data, and the remaining ~1% comes from mixed sources (seismic reflection, lidar, etc.).
Versions
IBCSO Version 1
500x500 meter resolution
coverage up to 60°S
IBCSO version 2
500x500 meter resolution
coverage up to 50°S
References
External links
IBCSO Version 1
IBCSO version 2
IBCSO Products
SCAR website of the IBCSO project
Current coverage of the world's oceans by SEABED2030 Project (hosted by the University of Stockholm, Sweden)
Oceanography
World maps
Hydrography | International Bathymetric Chart of the Southern Ocean | [
"Physics",
"Environmental_science"
] | 673 | [
"Hydrography",
"Oceanography",
"Hydrology",
"Applied and interdisciplinary physics"
] |
72,606,989 | https://en.wikipedia.org/wiki/Virivore | Virivore (equivalently virovore) comes from the English prefix viro- meaning virus, derived from the Latin word for poison, and the suffix -vore from the Latin word vorare, meaning to eat, or to devour; therefore, a virivore is an organism that consumes viruses. Virivory is a well-described process in which organisms, primarily heterotrophic protists, but also some metazoans consume viruses.
Viruses are considered a top predator in marine environments, as they can lyse microbes and release nutrients (i.e. the viral shunt). Viruses also play an important role in the structuring of microbial trophic relationships and regulation of carbon flow.
Discovery
The first described virovore was a small marine flagellate that was shown to ingest and digest virus particles. Subsequently, numerous studies directly and indirectly demonstrated the consumption of virions. In 2022, DeLong et al. showed that over the course of two days the ciliates Halteria and Paramecium reduced chlorovirus plaque-forming units by up to two orders of magnitude, supporting the idea that nutrients were transferred from the viruses to consumers.
Furthermore, the Halteria population grew with chlorovirus as the only source of nutrition, and grew minimally in the absence of chlorovirus. The Paramecium population, however, did not differ in growth when fed chloroviruses compared to the control group. Since the Paramecium population size remained constant in the presence of only cholorviruses, this indicated that Paramecium is capable of maintaining its population size, but not growing using chlorovirus as the sole carbon source. These data showed that some grazers can grow on viruses, but it does not apply to all grazers. It was estimated that Halteria consumed between 10,000 and 1,000,000 viruses per day. It's known that small protists, such as Halteria and Paramecium, are consumed by zooplankton indicating the movement of viral-derived energy and matter up through the aquatic food web. This contradicts the idea that the viral shunt limits the movement of energy up food webs by cutting off the grazer-microbe interaction. The amount of energy and matter passed up would depend on virion size and nutritional content, which would vary depending on the strain.
Biogeochemical impact
Viruses are the most abundant biological entities in the world's oceans. The life cycle of a lytic virus is an important process within the worlds oceans for the cycling of dissolved organic matter and particulate organic matter, i.e. the viral shunt. Viral particles themselves also make up a large proportion of the nitrogen and phosphorus rich particles within the dissolved organic matter pool, as they are made up of lipids, amino acids, nucleic acids, and likely carbon incorporated from host cells. It's considered that viruses can complement a grazers diet if ingested, and the microbe is not infected.
General grazing on viruses is widespread throughout the marine environment, with grazing rates as high as 90.3 mL−1 day−1. When both bacteria and viruses are present, viruses can be ingested at rates comparable to bacteria.
Using Oikopleura dioica and Equid alphaherpesvirus 1 (EhV) as a model, scientists estimated the nutritional gain from viruses;
24.2 ng C individual−1 day−1
2.8 ng N individual−1 day−1
0.2 ng P individual−1 day−1
It's suggested that in smaller grazers, viruses could potentially have a more significant impact on host nutrition. For example, in nanoflagellates, the estimated contribution is 9% carbon, 14% nitrogen, and 28% phosphorus.
While smaller bacteria are the ideal food source for grazers due to their size and carbon content, viruses are small, non-motile, and extremely abundant for grazers making them an alternative nutritional choice. For general grazers, to obtain the same amount of carbon from viruses that they get from bacteria, they would need to consume 1000 times more viruses. This does not make viruses the ideal carbon source for grazers. However, there are other benefits to consuming viruses besides growth. Studies show that digested viral particles release amino acids that the grazer can then utilize during their own polypeptide synthesis.
The viral sweep
Trophic interactions between grazers, bacteria, and viruses are important in regulating nutrient and organic matter cycling. The viral sweep is a mechanism in which grazers cycle carbon back into the classical food web by ingesting viral particles. Infection of host cells leads to the release of viral progeny, which are subsequently consumed by grazers. Grazers are then consumed by higher trophic organisms, therefore cycling carbon from viruses back into the classical food web and to higher trophic levels.
The viral sweep could be affected by many factors such as the size and abundance of the viral particles. The size of the virus will effect the elemental content of the virus particles. For example, a virus with a larger capsid will contribute more carbon, and viruses with larger genomes will contribute more nitrogen and phosphorus as a result of the increased nucleic acids. Additionally, the impact of the viral sweep could be more significant if grazers preying on bacteria infected with viruses are also considered. Overall, by consuming bacteria and viruses, grazers play an important role in cycling carbon.
Viral grazing
The consumption of viruses is largely based on the feeding behaviour of the organism.
Filter feeding
Filter feeding is a type of suspension feeding. Filter feeders usually actively capture single food particles on cili, hairs, mucus, or other structures. Researchers used Salpingeoca as a model filter feeder to observe change in viral abundance. Salpingeoca produce lorica to help them attach to the substrate. They also have one flagellum to create a water current which transports small particles towards them where tiny pseudopodia engulf the prey particles. When viruses were co-incubated with Salpingeoca, viral abundances decreased steadily over 90 days, showing that filter feeding is an effective mechanism for feeding on viruses.
Grazing on sediment particles
Grazers move over surfaces to gather and ingest food as they go. Researchers used Thaumatomonas coloniensis as a model grazer to observe changes in viral abundances. T. coloniensis glides along the substrate and produce filopodia, which are used to engulf particles associated with the substrate. Over the 90 days, viral abundances steadily decreased when co-incubated with T. coloniensis, showing that grazing is an effective mechanism for feeding on viruses.
Raptorial feeding
Raptorial feeding is a form of active feeding, in which the organism seeks out its prey. Researchers used Goniomonas truncata as a model of raptorial feeding. G. truncata is a cryptomonad that has two flagella which are used to swim close to the substrate searching for food, and they have vacuoles to aid in food uptake. In the presence of G. truncata, viral abundances did not significantly decrease over the course of 90 days. However, this does not exclude the possibility that viral particles are taken up, and then released back into the environment. This data shows that raptorial feeding may not be a method of viral grazing, but it may have other ecological implications in terms of viral transmission.
Selective grazing
Grazing on viruses differs between viruses, and therefore it is subject to selective feeding. Flagellates are capable of ingesting many viruses of different sizes, with the smallest viruses having the lowest ingestion rate. There is huge diversity amongst marine viruses, including size, shape, morphology, and surface charge that may influence the selection, and therefore ingestion rates. Additionally, digestion rates of different viruses by the same flagellate were variable. This implies selection when grazing on viruses. For example, significant differences in virus removal by Tetrahymena pyriformis was observed when the protist was co-incubated with 13 different types of viruses. Additionally, the removal rates for the specific viruses were maintained when the protist was co-incubated with multiple viruses at once. T. pyriformis were able to identify viruses as food, which drives their movement and consumption of certain viruses over others, supporting the idea that some protists are capable of selective grazing.
Impact of viral infection on grazing
Viruses have the capacity to influence the grazing of their host cells during infection, showing that viral infection plays a role in selective grazing.
Copepods are a key link in marine food webs as they connect primary and secondary production with higher trophic levels. When phytoplankton Emiliania huxleyi were infected with the coccolithovirus EhV-86, ingestion of the infected cells by the calanoid copepod Acartia tonsa was significantly reduced compared to non-infected cells, indicating selective grazing against infected cells. These results suggest that viral infections reduce grazing, and may potentially reduce food web efficiency by keeping the carbon within the viral shunt-microbial loop, and inhibiting the movement of carbon to higher trophic levels. This emphasizes the importance of the viral sweep for cycling carbon into higher trophic levels.
Conversely, Oxyrrhis marina had a grazing preference for virally infected Emiliania huxleyi. It's suggested that the preference of infected cells over non-infected cells is due to physiological changes or change in size of the host cell. O. marina prefer to graze on larger cells as they could potentially get a greater nutritional value from them compared to a smaller cell, which would require the same amount of energy to consume. Infected E. huxleyi exhibit increased cell size compared to non-infected, making them an ideal prey for O. marina. Infected E. huxleyi may also be selected for their palatability as a result of physiological changes during infection. For example, infected cells will have higher nucleic acid content compared to non-infected cells which could improve the nutritional gain to the grazers. Additionally, grazing activity of O. marina has been linked to prey with lower dimethylsulfoniopropionate lyase (DMSP lyase) activity, as they would produce less of the potentially toxic compound acrylate. Virally infected E. huxleyi show reduced levels of DMSP lyase activity, which makes them appealing to O. marina by reducing their exposure to harmful compounds. Lastly, chemical cues such as the release of dimethyl sulfide and hydrogen peroxide during infection likely generate a gradient, making it easier for O. marina to locate the infected E. huxleyi. Preferential grazing on infected cells would make the carbon available to higher trophic levels by sequestering it in particulate form.
Overall, grazing on virus particles and virally infected cells are subject to selective grazing.
Ecological significance
Studies have shown that viruses may be ingested and digested, or ingested and released back into the environment by grazers. The observation that grazers could potentially release viruses back into the environment after ingestion could have significant ecological impacts.
Mode of transmission
The ingestion and release of viruses could mediate the transmission and dispersal of viruses in the marine environment. Using copepods as the model transmission vector, and EhV as the model virus, Frada et al. identified a potential mechanism of viral dispersal in marine environments.
EhV particles can be consumed by copepods either as individual virion particles or via host cell infection (in this case, infected Emiliania huxleyi). When infected E. huxleyi was co-incubated with copepods, the fecal pellets produced by the copepods contained an average of 4500 EhVs per pellet. These virion containing pellets were then co-incubated with a fresh culture of E. huxleyi, and rapid viral-mediated lysis of the host cells was observed. When EhV particles alone were co-incubated with copepods, i.e. no E. huxleyi, the fecal particles collected did not contain any virion particles. However, when they fed copepods EhV and Thalassiosira weissflogii, a diatom outside the host range of EhV, the fecal pellets collected contained 200 EhVs per pellet. These pellets when co-incubated with a fresh E. huxleyi culture were highly infectious and completely killed the culture. The absence of virion particles in the fecal pellets produced from sole EhV incubation supports the idea that grazers exhibit selective grazing for viruses. EhV can still be taken up by copepods through host cell infection and when in the presence of an ideal food source. Since viral abundance follows bacterial abundance, it is unlikely that there will be a marine environment where viruses will be the sole nutrient source for grazers.
The results of this experiment have significant ecological impacts. Copepods are capable of moving up and down the water column, and migrating short distances between feeding zones. Specifically, for copepods and EhV, the movement of copepods can transport viruses into new and non-infected populations of E. huxleyi, promoting bloom demise. Additionally, fecal pellets can sink from the mixed layer into deeper parts of the ocean, where they can be assimilated multiple times. These two scenarios represent potential mechanisms in which viruses can be introduced into new marine environments.
Non-host organisms
Grazers are not the only organisms capable of removing viruses from the water column. Non-host organisms such as anemones, polychaeta larvae, sea squirts, crabs, cockles, oysters, and sponges are all capable of significantly reducing the viral abundance. Sponges were found to have the greatest potential for removing viruses.
The method in which non-host organisms disrupt the viral-host contact is known as transmission interference. Non-host organisms can either have a direct impact by removing the host-organisms, or an indirect one by removing the viruses. These mechanisms cause a reduction in the virus-host contact rates which could significantly impact local microbial population dynamics.
Non-host organisms are capable of removing viruses at rates comparable to natural food particles, bacterial cells, and algal cells, which is higher when compared to grazers that have a viral clearance rate around 4%. In regions of high sponge densities, such as coastal and tropical regions, it is likely that the virus removal rate has been underestimated. The effective removal of viruses likely has global ecological impacts that have gone unrecognized.
References
Further reading
Viruses
Microbiology
Ecology terminology | Virivore | [
"Chemistry",
"Biology"
] | 3,044 | [
"Viruses",
"Ecology terminology",
"Tree of life (biology)",
"Microbiology",
"Microscopy",
"Microorganisms"
] |
72,607,033 | https://en.wikipedia.org/wiki/Stormvloedkering%20Hollandse%20IJssel | The (English: Hollandse IJssel Storm Surge Barrier), (Hollandse IJssel Barrier) or (Algera Barrier) is a storm surge barrier located on the Hollandse IJssel, at the municipal boundary of Capelle aan den IJssel and Krimpen aan den IJssel, east of Rotterdam in The Netherlands. The construction of the works comprised the first project of the Delta Works, undertaken in response to the disastrous effects of the North Sea flood of 1953. Prior to 1954, the spelling was used in the official name.
The Hollandse IJssel is a low-lying river, and during the 1953 flood, the river dikes were exposed to dangerously high water levels, placing around 1.5 million people in the Randstad at risk from flooding. A dike at Ouderkerk aan den IJssel failed, and a dike in Nieuwerkerk aan den IJssel was almost breached, being sealed only after the local mayor ordered sailor Arie Evegroen to navigate his barge into the hole which had been formed in it. The body in charge of the Delta Works, the , therefore prioritised the construction of a storm surge barrier, and in January 1954, less than a year after the flood, dredging works were undertaken to start the project.
On May 6, 1958, the first sluice gate was lowered as a test, with the storm surge barrier made operational on 22 October 1958. The barrier is often referred to colloquially as the , but has never been officially known by that name. The name arises as the adjacent bridge carrying the N210 road is officially named the (Algera Bridge), after Jacob Algera, who resigned as Minister of Transport and Water Management for health reasons on 10 October 1958, only twelve days before the opening of the project. The architect was J.A.G. van der Steur Jr., and the project was designed by the department of Rijkswaterstaat, with H.G. Kroon as construction engineer.
The barrier is classified as a Rijksmonument. The four towers of the barrier are lit to act as aids to navigation, with blue lighting indicating an open barrier and red lighting indicating that the barrier is closed.
Design and planning
As the Hollandse IJssel is an important shipping route, the option of permanently closing the river with a dam was not taken forward. However, the potential advantages of a closure included increased supply security of drinking water for large parts of South Holland, by reducing the inflow of seawater into the polders. A storm surge barrier with two movable sluice gates, suspended between concrete towers, was chosen as the solution. The sluices are only closed at periods of very high water, with shipping able to sail underneath the raised gates at other times.
The , a 23.9 metre wide, 139 metre long control lock located north-west of the barrier, permits ships up to CEMT Class Va to navigate beyond the barrier at times of closure. A bascule bridge is located within the structure, having a closed clearance height of 7.11 metres.
The project was designed such that the two gates could be operated independently, minimising the risks from failure and permitting regular maintenance. Due to budgetary constraints, the second sluice gate did not come into operation until 1976, by which time the barrier had operated with a single sluice gate for almost 18 years. The gates were designed for different load cases and water levels on both sides of the barrier, as shown in the table below.
Construction and operation
The towers are 45 metres high, and the barrier gates are 12 metres high, 80 metres in width, and 135 metres apart. The total weight of each gate is 480 tonnes. Construction of the foundations involved steel sheet piles being installed in pairs, with ground anchors welded to the bottom of the piles to transfer loads to the foundation concrete. The towers are constructed of reinforced concrete with precast concrete slabs forming two floors at the top of each structure, one containing the cable wheels for the sluice counterweight, and the other housing the mechanical parts of the lifting mechanism.
Eight galvanised wire rope lifting and lowering cables with steel cores were used, guided over two 4.8 metre diameter cable wheels at the top of each tower, mounted on a forged steel axle with two self-aligning spherical roller bearings. The mechanism allowed the gates to be moved at a rate between 2 and 3 centimetres per second. The gates were fabricated and assembled in Dordrecht before being transported to site on barges, via Rotterdam, for installation.
The total construction cost of the Hollandse IJssel Storm Surge Barrier amounted to approximately forty million guilders. One barrier is closed at an anticipated water level of 2.25 metres above Amsterdam Ordnance Datum (NAP). Closure of the barrier takes between 20 and 60 minutes. The barrier is closed four to five times per year on average, and is also closed once per month on a test basis during the storm season between October and April.
The Algera Bridge
The Algera Bridge, the first major fixed cross-river connection between Krimpenerwaard and the mainland of South Holland, consists of a fixed bridge over the river and a bascule bridge over the lock. The fixed bridge is supported on two piers, one of which forms the transition to a viaduct on the east side, with the other forming a support for the bascule bridge. West of the bridge, there is an underpass designed to allow north–south traffic to pass uninterrupted.
The effects of the construction of the Maeslantkering
The construction of the Maeslant barrier in 1997 resulted in a higher factor of safety from flooding for the areas behind it, including areas protected by the Hollandse IJsselkering. The Maeslant barrier is designed for very extreme floods (when the water level is predicted to be 3 metres or more above NAP in Rotterdam). On average, this occurs once every 10 years. When the Maeslant barrier is closed, the entrance to the old port of Rotterdam at is closed to all shipping for at least 24 hours. The dikes behind the Hollandse IJsselkering can only cope with water levels up to 2.25 metres above NAP, and therefore it is closed more often than the Maeslant barrier - around 3 to 4 times per year.
Although it would be technically possible to abandon the Hollandse IJsselkering and close the Maeslantkering more frequently, the undesirable economic effects arising from the associated shipping disruption mean that the Hollandse IJsselkering remains in operation. In addition, the operation to close the Maeslant barrier takes much longer than the Hollandse IJsselkering, which can be completely closed in around 4 hours. Closure of the Maeslantkering is therefore reserved only for extreme high water levels and the Hollandse IJsselkering remains essential to Rijkswaterstaat's overall flood management strategy.
Media
See also
Delta Works
Flood control in the Netherlands
Rijkswaterstaat
References
External links
Hollandse IJssel Storm Surge Barrier details at the Watersnoodmuseum Knowledge Centre Information on the Hollandse IJssel storm surge barrier from the official Watersnoodmuseum website
Deltawerk Hollandse IJsselkering Official information page about the barrier on the Rijkswaterstaat website
Dams in South Holland
Dams completed in 1958
Delta Works | Stormvloedkering Hollandse IJssel | [
"Physics"
] | 1,537 | [
"Physical systems",
"Hydraulics",
"Delta Works"
] |
72,607,666 | https://en.wikipedia.org/wiki/Hallucination%20%28artificial%20intelligence%29 | In the field of artificial intelligence (AI), a hallucination or artificial hallucination (also called bullshitting, confabulation or delusion) is a response generated by AI that contains false or misleading information presented as fact. This term draws a loose analogy with human psychology, where hallucination typically involves false percepts. However, there is a key difference: AI hallucination is associated with erroneous responses rather than perceptual experiences.
For example, a chatbot powered by large language models (LLMs), like ChatGPT, may embed plausible-sounding random falsehoods within its generated content. Researchers have recognized this issue, and by 2023, analysts estimated that chatbots hallucinate as much as 27% of the time, with factual errors present in 46% of generated texts. Detecting and mitigating these hallucinations pose significant challenges for practical deployment and reliability of LLMs in real-world scenarios. Some researchers believe the specific term "AI hallucination" unreasonably anthropomorphizes computers.
Term
Origin
In 1995, Stephen Thaler demonstrated how hallucinations and phantom experiences emerge from artificial neural networks through random perturbation of their connection weights.
In the early 2000s, the term "hallucination" was used in computer vision with a positive connotation to describe the process of adding detail to an image. For example, the task of generating high-resolution face images from low-resolution inputs is called face hallucination.
In the late 2010s, the term underwent a semantic shift to signify the generation of factually incorrect or misleading outputs by AI systems in tasks like translation or object detection. For example, in 2017, Google researchers used the term to describe the responses generated by neural machine translation (NMT) models when they are not related to the source text, and in 2018, the term was used in computer vision to describe instances where non-existent objects are erroneously detected because of adversarial attacks.
The term "hallucinations" in AI gained wider recognition during the AI boom, alongside the rollout of widely used chatbots based on large language models (LLMs). In July 2021, Meta warned during its release of BlenderBot 2 that the system is prone to "hallucinations", which Meta defined as "confident statements that are not true". Following OpenAI's ChatGPT release in beta-version in November 2022, some users complained that such chatbots often seem to pointlessly embed plausible-sounding random falsehoods within their generated content. Many news outlets, including The New York Times, started to use the term "hallucinations" to describe these model's occasionally incorrect or inconsistent responses.
In 2023, some dictionaries updated their definition of hallucination to include this new meaning specific to the field of AI.
Criticism
The term "hallucination" has been criticized by Usama Fayyad, executive director of the Institute for Experimental Artificial Intelligence at Northeastern University, on the grounds that it misleadingly personifies large language models, and that it is vague.
In natural language processing
In natural language processing, a hallucination is often defined as "generated content that appears factual but is ungrounded". There are different ways to categorize hallucinations. Depending on whether the output contradicts the source or cannot be verified from the source, they are divided into intrinsic and extrinsic, respectively. Depending on whether the output contradicts the prompt or not they could be divided into closed-domain and open-domain respectively.
Causes
There are several reasons for natural language models to hallucinate data.
Hallucination from data
The main cause of hallucination from data is source-reference divergence. This divergence happens 1) as an artifact of heuristic data collection or 2) due to the nature of some NLG tasks that inevitably contain such divergence. When a model is trained on data with source-reference (target) divergence, the model can be encouraged to generate text that is not necessarily grounded and not faithful to the provided source.
Hallucination from modeling
Hallucination was shown to be a statistically inevitable byproduct of any imperfect generative model that is trained to maximize training likelihood, such as GPT-3, and requires active learning (such as reinforcement learning from human feedback) to be avoided. Other research takes an anthropomorphic perspective and posits hallucinations as arising from a tension between novelty and usefulness. For instance, Teresa Amabile and Pratt define human creativity as the production of novel and useful ideas. By extension, a focus on novelty in machine creativity can lead to production of original but inaccurate responses, i.e. falsehoods, whereas a focus on usefulness can result in ineffectual rote memorized responses.
Errors in encoding and decoding between text and representations can cause hallucinations. When encoders learn the wrong correlations between different parts of the training data, it could result in an erroneous generation that diverges from the input.
The decoder takes the encoded input from the encoder and generates the final target sequence. Two aspects of decoding contribute to hallucinations. First, decoders can attend to the wrong part of the encoded input source, leading to erroneous generation. Second, the design of the decoding strategy itself can contribute to hallucinations. A decoding strategy that improves the generation diversity, such as top-k sampling, is positively correlated with increased hallucination.
Pre-training of models on a large corpus is known to result in the model memorizing knowledge in its parameters, creating hallucinations if the system is overconfident in its hardwired knowledge. In systems such as GPT-3, an AI generates each next word based on a sequence of previous words (including the words it has itself previously generated during the same conversation), causing a cascade of possible hallucination as the response grows longer. By 2022, papers such as The New York Times expressed concern that, as adoption of bots based on large language models continued to grow, unwarranted user confidence in bot output could lead to problems.
Examples
On 15 November 2022, researchers from Meta AI published Galactica, designed to "store, combine and reason about scientific knowledge". Content generated by Galactica came with the warning "Outputs may be unreliable! Language Models are prone to hallucinate text." In one case, when asked to draft a paper on creating avatars, Galactica cited a fictitious paper from a real author who works in the relevant area. Meta withdrew Galactica on 17 November due to offensiveness and inaccuracy. Before the cancellation, researchers were working on Galactica Instruct, which would use instruction tuning to allow the model to follow instructions to manipulate LaTeX documents on Overleaf.
OpenAI's ChatGPT, released in beta-version to the public on November 30, 2022, is based on the foundation model GPT-3.5 (a revision of GPT-3). Professor Ethan Mollick of Wharton has called ChatGPT an "omniscient, eager-to-please intern who sometimes lies to you". Data scientist Teresa Kubacka has recounted deliberately making up the phrase "cycloidal inverted electromagnon" and testing ChatGPT by asking it about the (nonexistent) phenomenon. ChatGPT invented a plausible-sounding answer backed with plausible-looking citations that compelled her to double-check whether she had accidentally typed in the name of a real phenomenon. Other scholars such as Oren Etzioni have joined Kubacka in assessing that such software can often give "a very impressive-sounding answer that's just dead wrong".
When CNBC asked ChatGPT for the lyrics to "Ballad of Dwight Fry", ChatGPT supplied invented lyrics rather than the actual lyrics. Asked questions about New Brunswick, ChatGPT got many answers right but incorrectly classified Samantha Bee as a "person from New Brunswick". Asked about astrophysical magnetic fields, ChatGPT incorrectly volunteered that "(strong) magnetic fields of black holes are generated by the extremely strong gravitational forces in their vicinity". (In reality, as a consequence of the no-hair theorem, a black hole without an accretion disk is believed to have no magnetic field.) Fast Company asked ChatGPT to generate a news article on Tesla's last financial quarter; ChatGPT created a coherent article, but made up the financial numbers contained within.
Other examples involve baiting ChatGPT with a false premise to see if it embellishes upon the premise. When asked about "Harold Coward's idea of dynamic canonicity", ChatGPT fabricated that Coward wrote a book titled Dynamic Canonicity: A Model for Biblical and Theological Interpretation, arguing that religious principles are actually in a constant state of change. When pressed, ChatGPT continued to insist that the book was real. Asked for proof that dinosaurs built a civilization, ChatGPT claimed there were fossil remains of dinosaur tools and stated "Some species of dinosaurs even developed primitive forms of art, such as engravings on stones". When prompted that "Scientists have recently discovered churros, the delicious fried-dough pastries ... (are) ideal tools for home surgery", ChatGPT claimed that a "study published in the journal Science found that the dough is pliable enough to form into surgical instruments that can get into hard-to-reach places, and that the flavor has a calming effect on patients.
By 2023, analysts considered frequent hallucination to be a major problem in LLM technology, with a Google executive identifying hallucination reduction as a "fundamental" task for ChatGPT competitor Google Bard. A 2023 demo for Microsoft's GPT-based Bing AI appeared to contain several hallucinations that went uncaught by the presenter.
In May 2023, it was discovered that Stephen Schwartz had submitted six fake case precedents generated by ChatGPT in his brief to the Southern District of New York on Mata v. Avianca, a personal injury case against the airline Avianca. Schwartz said that he had never previously used ChatGPT, that he did not recognize the possibility that ChatGPT's output could have been fabricated, and that ChatGPT continued to assert the authenticity of the precedents after their nonexistence was discovered. In response, Brantley Starr of the Northern District of Texas banned the submission of AI-generated case filings that have not been reviewed by a human, noting that:
On June 23, judge P. Kevin Castel dismissed the Mata case and issued a $5,000 fine to Schwartz and another lawyer—who had both continued to stand by the fictitious precedents despite Schwartz's previous claims—for bad faith conduct. Castel characterized numerous errors and inconsistencies in the opinion summaries, describing one of the cited opinions as "gibberish" and "[bordering] on nonsensical".
In June 2023, Mark Walters, a gun rights activist and radio personality, sued OpenAI in a Georgia state court after ChatGPT mischaracterized a legal complaint in a manner alleged to be defamatory against Walters. The complaint in question was brought in May 2023 by the Second Amendment Foundation against Washington attorney general Robert W. Ferguson for allegedly violating their freedom of speech, whereas the ChatGPT-generated summary bore no resemblance and claimed that Walters was accused of embezzlement and fraud while holding a Second Amendment Foundation office post that he never held in real life. According to AI legal expert Eugene Volokh, OpenAI is likely not shielded against this claim by Section 230, because OpenAI likely "materially contributed" to the creation of the defamatory content.
Scientific research
Problems
AI models can cause problems in the world of academic and scientific research due to their hallucinations. Specifically, models like ChatGPT have been recorded in multiple cases to cite sources for information that are either not correct or do not exist. A study conducted in the Cureus Journal of Medical Science showed that out of 178 total references cited by GPT-3, 69 returned an incorrect or nonexistent digital object identifier (DOI). An additional 28 had no known DOI nor could be located in a Google search.
Another instance was documented by Jerome Goddard from Mississippi State University. In an experiment, ChatGPT had provided questionable information about ticks. Unsure about the validity of the response, they inquired about the source that the information had been gathered from. Upon looking at the source, it was apparent that the DOI and the names of the authors had been hallucinated. Some of the authors were contacted and confirmed that they had no knowledge of the paper's existence whatsoever. Goddard says that, "in [ChatGPT's] current state of development, physicians and biomedical researchers should NOT ask ChatGPT for sources, references, or citations on a particular topic. Or, if they do, all such references should be carefully vetted for accuracy." The use of these language models is not ready for fields of academic research and that their use should be handled carefully.
On top of providing incorrect or missing reference material, ChatGPT also has issues with hallucinating the contents of some reference material. A study that analyzed a total of 115 references provided by ChatGPT documented that 47% of them were fabricated. Another 46% cited real references but extracted incorrect information from them. Only the remaining 7% of references were cited correctly and provided accurate information. ChatGPT has also been observed to "double-down" on a lot of the incorrect information. When asked about a mistake that may have been hallucinated, sometimes ChatGPT will try to correct itself but other times it will claim the response is correct and provide even more misleading information.
These hallucinated articles generated by language models also pose an issue because it is difficult to tell whether an article was generated by an AI. To show this, a group of researchers at the Northwestern University of Chicago generated 50 abstracts based on existing reports and analyzed their originality. Plagiarism detectors gave the generated articles an originality score of 100%, meaning that the information presented appears to be completely original. Other software designed to detect AI generated text was only able to correctly identify these generated articles with an accuracy of 66%. Research scientists had a similar rate of human error, identifying these abstracts at a rate of 68%. From this information, the authors of this study concluded, "[t]he ethical and acceptable boundaries of ChatGPT's use in scientific writing remain unclear, although some publishers are beginning to lay down policies." Because of AI's ability to fabricate research undetected, the use of AI in the field of research will make determining the originality of research more difficult and require new policies regulating its use in the future.
Given the ability of AI generated language to pass as real scientific research in some cases, AI hallucinations present problems for the application of language models in the Academic and Scientific fields of research due to their ability to be undetectable when presented to real researchers. The high likelihood of returning non-existent reference material and incorrect information may require limitations to be put in place regarding these language models. Some say that rather than hallucinations, these events are more akin to "fabrications" and "falsifications" and that the use of these language models presents a risk to the integrity of the field as a whole.
Benefits
Scientists have also found that hallucinations can serve as a valuable tool for scientific discovery, particularly in fields requiring innovative approaches to complex problems. At the University of Washington, David Baker's lab has used AI hallucinations to design "ten million brand-new" proteins that don't occur in nature, leading to roughly 100 patents and the founding of over 20 biotech companies. This work contributed to Baker receiving the 2023 Nobel Prize in Chemistry, although the committee avoided using the "hallucinations" language.
In medical research and device development, hallucinations have enabled practical innovations. At California Institute of Technology, researchers used hallucinations to design a novel catheter geometry that significantly reduces bacterial contamination. The design features sawtooth-like spikes on the inner walls that prevent bacteria from gaining traction, potentially addressing a global health issue that causes millions of urinary tract infections annually. These scientific application of hallucinations differs fundamentally from chatbot hallucinations, as they are grounded in physical reality and scientific facts rather than ambiguous language or internet data. Anima Anandkumar, a professor at Caltech, emphasizes that these AI models are "taught physics" and their outputs must be validated through rigorous testing. In meteorology, scientists use AI to generate thousands of subtle forecast variations, helping identify unexpected factors that can influence extreme weather events.
At Memorial Sloan Kettering Cancer Center, researchers have applied hallucinatory techniques to enhance blurry medical images, while the University of Texas at Austin has utilized them to improve robot navigation systems. These applications demonstrate how hallucinations, when properly constrained by scientific methodology, can accelerate the discovery process from years to days or even minutes.
Terminologies
In Salon, statistician Gary N. Smith argues that LLMs "do not understand what words mean" and consequently that the term "hallucination" unreasonably anthropomorphizes the machine. Journalist Benj Edwards, in Ars Technica, writes that the term "hallucination" is controversial, but that some form of metaphor remains necessary; Edwards suggests "confabulation" as an analogy for processes that involve "creative gap-filling".
In the scientific community, some researchers avoid the term "hallucination" as potentially misleading. Some see the AI outputs not as illusory but as prospective—having (some chance of being true), similar to early-stage scientific conjectures. The term has also been criticized for its association with psychedelic drug experiences. In July 2024, a White House report on fostering public trust in AI research mentioned hallucinations only in the context of reducing them. Notably, when acknowledging David Baker's Nobel Prize-winning work with AI-generated proteins, the Nobel committee avoided the term entirely, instead referring to "imaginative protein creation."
A list of uses of the term "hallucination", definitions or characterizations in the context of LLMs include:
"a tendency to invent facts in moments of uncertainty" (OpenAI, May 2023)
"a model's logical mistakes" (OpenAI, May 2023)
"fabricating information entirely, but behaving as if spouting facts" (CNBC, May 2023)
"making up information" (The Verge, February 2023)
"probability distributions" (in scientific contexts)
In other artificial intelligence use
The concept of "hallucination" is applied more broadly than just natural language processing. A confident response from any AI that seems erroneous by the training data can be labeled a hallucination.
Object detection
Various researchers cited by Wired have classified adversarial hallucinations as a high-dimensional statistical phenomenon, or have attributed hallucinations to insufficient training data. Some researchers believe that some "incorrect" AI responses classified by humans as "hallucinations" in the case of object detection may in fact be justified by the training data, or even that an AI may be giving the "correct" answer that the human reviewers are failing to see. For example, an adversarial image that looks, to a human, like an ordinary image of a dog, may in fact be seen by the AI to contain tiny patterns that (in authentic images) would only appear when viewing a cat. The AI is detecting real-world visual patterns that humans are insensitive to.
Wired noted in 2018 that, despite no recorded attacks "in the wild" (that is, outside of proof-of-concept attacks by researchers), there was "little dispute" that consumer gadgets, and systems such as automated driving, were susceptible to adversarial attacks that could cause AI to hallucinate. Examples included a stop sign rendered invisible to computer vision; an audio clip engineered to sound innocuous to humans, but that software transcribed as "evil dot com"; and an image of two men on skis, that Google Cloud Vision identified as 91% likely to be "a dog". However, these findings have been challenged by other researchers. For example, it was objected that the models can be biased towards superficial statistics, leading adversarial training to not be robust in real-world scenarios.
Text-to-audio generative AI
Text-to-audio generative AI more narrowly known as text-to-speech (TTS) synthesis, depending on the modality are known to produce inaccurate and unexpected results.
Text-to-image generative AI
Text-to-image models, such as Stable Diffusion, Midjourney and others, while impressive in their ability to generate images from text descriptions, often produce inaccurate or unexpected results.
One notable issue is the generation of historically inaccurate images. For instance, Gemini depicted ancient Romans as black individuals or Nazi German soldiers as people of color, causing controversy and leading Google to pause image generation involving people in Gemini.
Text-to-video generative AI
Text-to-video generative models, like Sora, can introduce inaccuracies in generated videos. One example involves the Glenfinnan Viaduct, a famous landmark featured in the Harry Potter film series. Sora mistakenly added a second track to the viaduct railway, resulting in an unrealistic depiction.
Mitigation methods
The hallucination phenomenon is still not completely understood. Researchers have also proposed that hallucinations are inevitable and are an innate limitation of large language models. Therefore, there is still ongoing research to try to mitigate its occurrence. Particularly, it was shown that language models not only hallucinate but also amplify hallucinations, even for those which were designed to alleviate this issue.
Ji et al. divide common mitigation method into two categories: data-related methods and modeling and inference methods. Data-related methods include building a faithful dataset, cleaning data automatically and information augmentation by augmenting the inputs with external information. Model and inference methods include changes in the architecture (either modifying the encoder, attention or the decoder in various ways), changes in the training process, such as using reinforcement learning, along with post-processing methods that can correct hallucinations in the output.
Researchers have proposed a variety of mitigation measures, including getting different chatbots to debate one another until they reach consensus on an answer. Another approach proposes to actively validate the correctness corresponding to the low-confidence generation of the model using web search results. They have shown that a generated sentence is hallucinated more often when the model has already hallucinated in its previously generated sentences for the input, and they are instructing the model to create a validation question checking the correctness of the information about the selected concept using Bing search API. An extra layer of logic-based rules was proposed for the web search mitigation method, by utilizing different ranks of web pages as a knowledge base, which differ in hierarchy. When there are no external data sources available to validate LLM-generated responses (or the responses are already based on external data as in RAG), model uncertainty estimation techniques from machine learning may be applied to detect hallucinations.
According to Luo et al., the previous methods fall into knowledge and retrieval-based approaches which ground LLM responses in factual data using external knowledge sources, such as path grounding. Luo et al. also mention training or reference guiding for language models, involving strategies like employing control codes or contrastive learning to guide the generation process to differentiate between correct and hallucinated content. Another category is evaluation and mitigation focused on specific hallucination types, such as employing methods to evaluate quantity entity in summarization and methods to detect and mitigate self-contradictory statements.
Nvidia Guardrails, launched in 2023, can be configured to hard-code certain responses via script instead of leaving them to the LLM. Furthermore, numerous tools like SelfCheckGPT, the Trustworthy Language Model, and Aimon have emerged to aid in the detection of hallucination in offline experimentation and real-time production scenarios.
See also
AI alignment
AI effect
AI safety
Artifact
Artificial stupidity
Turing test
Uncanny valley
References
Communication of falsehoods
Computational linguistics
Computational neuroscience
Deep learning
Disinformation
Language modeling
Machine learning
Misinformation
Software bugs
Generative artificial intelligence
Philosophy of artificial intelligence
Unsupervised learning | Hallucination (artificial intelligence) | [
"Technology",
"Engineering"
] | 5,100 | [
"Generative artificial intelligence",
"Machine learning",
"Computational linguistics",
"Artificial intelligence engineering",
"Natural language and computing"
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72,608,669 | https://en.wikipedia.org/wiki/Calcareous%20nannofossils | Calcareous nannofossils are a class of tiny (less than 30 microns in diameter) microfossils that are similar to coccoliths deposited by the modern-day coccolithophores. The nannofossils are a convenient source of geochronological data due to the abundance and rapid evolution of the single-cell organisms forming them (nannoplankton) and ease of handling of the sediment samples. The practical applications of calcareous nannofossils in the areas of biostratigraphy and paleoecology became clear once the deepwater drilling took off in 1968 with the Deep Sea Drilling Project, and they have been extensively studied ever since. Nannofossils provide one of the most important paleontological records with the contiguous length of 220 million years.
History of research
Christian Gottfried Ehrenberg, while examining the chalk from Ruegen, recorded in 1836 an observation of what was later termed "coccolith" and had pictured the coccoliths and Discoasters in his Mikrogeologie (1854), erroneously classifying these discs as a kind of complex spheric concretion. T. H. Huxley coined the term coccoliths in 1858 (due to their shape resembling the Protococcus), while agreeing with their inorganic nature. In 1861 George Charles Wallich and, independently, Henry Clifton Sorby, figured out the organic nature of coccoliths after observing their aggregations, coccospheres. Huxley then changed his views and declared that coccoliths are skeletal elements of an unknown organism, Bathybius haeckelii, a primordial form of organic life. One of the goals of the Challenger expedition was to understand the nature of the Bathybius, but the scientists aboard the ship reached the conclusion that the gel-like substance apparently holding the disks in a coccosphere together was a result of processing the samples and later declared the coccoliths to constitute the defensive armor of tiny nannoplankton algae (the term was coined in 1909 by to identify the tiniest plankton, less than 60 microns in size, that passed through the regular phytoplankton nets).
Research of the nannoplankton systematics in the early 20th century (Erwin Kamptner, , and Trygve Braarud) enabled M. N. Bramlette and W. R. Riedel to successfully use the nannofossils for biostratigraphy (1954). The Deep Sea Drilling Project (DSDP, 1968) revealed the power of the technique: stratigraphic positions were found within minutes after the drilling core was hauled aboard the ship. At the same time, the continuous DSDP cores provided a solid foundation for setting up the nannofossil biozones. It took decades to establish comprehensive chronological schemes (e.g. Martini 1971; Sissingh 1977; Roth 1978; Okada & Bukry 1980).
The researchers started to use the transmission electron microscopes in the mid-1950s, switching to scanning electron microscopes in the 1960s and 1970s. Optical microscopes with cross-polarization and phase-contrast illumination, techniques introduced in 1952 by Kamptner and Braarud & Nordli respectively, are still used for routine field work.
Terminology
The terminology in the field evolved over time and nannofossils are also sometimes called "nannoplankton" and "coccoliths" as well as some other names, especially in the literature published in 1950s and 1960s. The term "calcareous nannofossil" was chosen in the DSDP publications (although it was rarely used prior to that) and gained popularity afterwards, in the early 1970s. "Calcareous" is derived from , "lime", and means "containing lime".
Siesser & Haq describe the general use as follows:
coccolith is restricted by some authors to designate round-shaped elements similar to the ones produced by the living coccolithophores. For differently-shaped objects (e. g., stars and horseshoes), nanolith is being used. Some other authors, however, use coccolith in a broader sense for all calcareous nanofossils;
nannoplankton is sometimes used to identify the living organisms, with nannofossils referring to the now-extinct species. Other researchers use the nannoplankton for all forms, both living and extinct arguing that even though the true taxonomy of the extinct ones might never be known, their planktic way of living is subject to little doubt.
Siesser & Haq themselves use nannoplankton as a generic way to refer to all organisms, whether living or extinct and nannofossils when describing specifically the fossil forms.
Biostratigraphy
Multiple characteristics of the calcareous nannofossils make them a valuable tool of biostratigraphy and biochronology:
continuous record from 220 million years ago to present;
abundance in marine sediments;
worldwide distribution due to the planktonic nature;
rapid evolution (with diverse morphology) that provides hundreds of points of appearance and extinction;
tiny size allows the work to be performed with small samples (less than 1 gramm).
The calcareous nannofossils can be found in the deposits that stretch from the Late Triassic to the modern times. The calcareous nannoplankton biodiversity grew in the Jurassic and Cretaceous periods peaking at about 150 species in the Late Cretaceous.
The boundaries of the biozones in stratigraphy are defined by the biohorizons, points in strata where significant changes in fossil content and distribution occur. Typical events used for biohorizons are: first occurrence, last occurrence, change in abundance of taxons. A combination of biozones arranged in stratigraphical order results in a zonation (or scheme).
The first Cenozoic biozonation with 21 biozones for Neogene and 25 biozones for Palaeogene was published in 1971 by Martini, it used alphanumeric notation starting with NN for the Neogene and NP for the Palaeogene (first N stands for Nannoplankton), the enumeration increased from the deepest stratigraphic layer. Okada & Bukry introduced their schemes in 1980 with zones code-numbered with letters CN and CP (C stands for Coccolith). Agnini et al. in 2017 had combined the scales, reintroducing the new biohorizons for the unreliable ones, resulting in schemes coded with CNP for Palaeocene, CNE for Eocene, CNO for Oligocene, CNM for Miocene, CNPL for Pliocene/Pleistocene (CN stands for Calcareous Nannofossils).
The agreed upon stratification reference is codified as Global Boundary Stratotype Section and Point (GSSP) by the International Commission on Stratigraphy. The calcareous nannofossils, with very few exceptions, provide clear biohorizons indicating the positions of the GSSP boundaries in Cenozoic.
Other uses
Calcareous nannofossils are being used in archaeology to establish the provenance of various artefacts: ceramics, tesserae, grounds of paintings, statues, and masonry.
References
Sources
Microfossils
Biostratigraphy | Calcareous nannofossils | [
"Chemistry"
] | 1,550 | [
"Microfossils",
"Microscopy"
] |
72,610,476 | https://en.wikipedia.org/wiki/Cable-stayed%20suspension%20bridge | A cable-stayed suspension bridge or CSS bridge merges the designs of cable-stayed bridges and suspension bridges. The suspension bridge's architecture is better at handling the load in the middle of the bridge, while the cable stayed bridge is better suited to handle the load closest to the tower. Combining these two architectural engineering ideas into a hybrid has been done in Istanbul with the Yavuz Sultan Selim Bridge, and in New York City with the Brooklyn Bridge. A bridge over the Krishna River in India has been approved in October 2022 that will be a CSS bridge design.
Yavuz Sultan Selim Bridge
In Turkey the Yavuz Sultan Selim Bridge over the Bosporus Strait opened in August 2016. The main span is long and is the 13th-longest bridge span in the world.
See also
List of longest cable-stayed bridge spans
List of longest suspension bridge spans
List of cable-stayed bridges in the United States
List of bridge types
Floating cable-stayed bridge
Floating suspension bridge
References
Structural engineering
Building engineering | Cable-stayed suspension bridge | [
"Engineering"
] | 207 | [
"Structural engineering",
"Building engineering",
"Construction",
"Civil engineering",
"Architecture"
] |
72,612,198 | https://en.wikipedia.org/wiki/NGC%204200 | NGC 4200 is a lenticular galaxy located in the constellation Virgo.
References
External links
Virgo (constellation)
4200
Lenticular galaxies | NGC 4200 | [
"Astronomy"
] | 30 | [
"Virgo (constellation)",
"Constellations"
] |
72,612,865 | https://en.wikipedia.org/wiki/X%20Cygni | X Cygni is a variable star in the northern constellation of Cygnus, abbreviated X Cyg. This is a Delta Cephei variable that ranges in brightness from an apparent visual magnitude of 5.85 down to 6.91 with a period of 16.386332 days. At it brightest, this star is dimly visible to the naked eye. The distance to this star is approximately 3,690 light years based on parallax measurements. It is drifting further away with a radial velocity of 8.1 km/s. This star is a likely member of the open cluster Ruprecht 173.
The variable luminosity of this star was discovered by S. C. Chandler, Jr. in 1886. In 1907, E. B. Frost showed that X Cyg is an F-type star with a varying radial velocity, behaving analogous to a Delta Cephei variable. M. Luizet in 1912 found a cyclical pulsation period of 16.38543 days for the variation. In 1919, F. C. Jordan determined that the color index of the star changed over the course of each cycle, becoming redder as the star grew fainter. It came to be identified as a member of the benchmark class of stars termed Classical Cepheid variables that satisfy a simple period-luminosity relation.
In 1954, R. P. Kraft found a stellar classification of F7 Ib at peak brightness, matching the spectrum of an F-type supergiant star. The class of the star varies over the course of a pulsation cycle, ranging down to G8 Ib at minimum brightness. R. P. Kraft in 1956 identified a doubling of certain spectral lines, which he explained as the result of a falling shell of matter from a prior pulsation cycle that is colliding with the photosphere. Unlike most cepheid variables that undergo a single shock per cycle, X Cyg has been found to undergo a double shock.
No orbiting companion has been identified with a period of ten years or less. The star shows cirrus with tentative evidence for extended emission of infrared.
References
Further reading
F-type supergiants
Classical Cepheid variables
Cygnus (constellation)
7932
Durchmusterung objects
197572
102276
Cygni, X | X Cygni | [
"Astronomy"
] | 477 | [
"Cygnus (constellation)",
"Constellations"
] |
72,613,506 | https://en.wikipedia.org/wiki/Hexafluorotitanic%20acid | Hexafluorotitanic acid (systematically named oxonium hexafluoridotitanate(2-)) is an inorganic compound with the chemical formula (H3O)(H5O2)[TiF6]. According to X-ray crystallography, the salt consists of [TiF6]2- octahedral and two kinds of oxonium cations, (H3O)+ and (H5O2)+.
As with most oxonium salts, it is only stable in acidic solution. Under basic conditions, closely related salts hydrolyse to a hydrated titanium dioxide:
A related salt is the anhydrous fluoronium hexafluoridotitanate(2-) or (H2F)2[TiF6].
References
Fluorine compounds
Titanium(IV) compounds
Fluorometallates | Hexafluorotitanic acid | [
"Chemistry"
] | 188 | [
"Inorganic compounds",
"Inorganic compound stubs"
] |
72,614,183 | https://en.wikipedia.org/wiki/Permutationally%20invariant%20quantum%20state%20tomography | Permutationally invariant quantum state tomography (PI quantum state tomography) is a method for the partial determination of the state of a quantum system consisting of many subsystems.
In general, the number of parameters needed to describe the quantum mechanical state of a system consisting of subsystems is increasing exponentially with For instance, for an -qubit system, real parameters are needed to describe the state vector of a pure state, or
real parameters are needed to describe the density matrix of a mixed state. Quantum state tomography is a method to determine all these parameters from a series of measurements on many independent and identically prepared systems. Thus, in the case of full quantum state tomography, the number of measurements needed scales exponentially with the number of particles or qubits.
For large systems, the determination of the entire quantum state is no longer possible in practice and one is interested in methods that determine only a subset of the parameters necessary to characterize the quantum state that still contains important information about the state. Permutationally invariant quantum tomography is such a method. PI quantum tomography only measures the permutationally invariant part of the density matrix. For the procedure, it is sufficient to carry out local measurements on the subsystems. If the state is close to being permutationally invariant, which is the case in many practical situations, then is close to the density matrix of the system.
Even if the state is not permutationally invariant, can still be used for entanglement detection and computing relevant operator expectations values. Thus, the procedure does not assume the permutationally invariance of the quantum state. The number of independent real parameters of for qubits scales as The number of local measurement settings scales as Thus, permutationally invariant quantum tomography is considered manageable even for large . In other words, permutationally invariant quantum tomography is considered scalable.
The method can be used, for example, for the reconstruction of the density matrices of systems with more than 10 particles, for photonic systems, for trapped cold ions or systems in cold atoms.
The permutationally invariant part of the density matrix
PI state tomography reconstructs the permutationally invariant part of the density matrix, which is defined as the equal mixture of the quantum states obtained after permuting the particles in all the possible ways
where denotes the kth permutation. For instance, for we have two permutations. leaves the order of the two particles unchanged. exchanges the two particles. In general, for particles, we have permutations.
It is easy to see that is the density matrix that is obtained if the order of the particles is not taken into account. This corresponds to an experiment in which a subset of particles is randomly selected from a larger ensemble. The state of this smaller group is of course permutationally invariant.
The number of degrees of freedom of scales polynomially with the number of particles. For a system of qubits (spin- particles) the number of real degrees of freedom is
The measurements needed to determine the permutationally invariant part of the density matrix
To determine these degrees of freedom,
local measurement settings are needed. Here, a local measurement settings means that the operator is to be measured on each particle. By repeating the measurement and collecting enough data, all two-point, three-point and higher order correlations can be determined.
Efficient determination of a physical state
So far we have discussed that the number of measurements scales polynomially with the number of qubits.
However, for using the method in practice, the entire tomographic procedure must be scalable. Thus, we need to store the state in the computer in a scalable way. Clearly, the straightforward way of storing the -qubit state in a density matrix is not scalable. However, is a blockdiagonal matrix due to its permutational invariance and thus it can be stored much more efficiently.
Moreover, it is well known that due to statistical fluctuations and systematic errors the density matrix obtained from the measured state by linear inversion is not positive semidefinite and it has some negative eigenvalues. An important step in a typical tomography is fitting a physical, i. e., positive semidefinite density matrix on the tomographic data. This step often represents a bottleneck in the overall process in full state tomography. However, PI tomography, as we have just discussed, allows the density matrix to be stored much more efficiently, which also allows an efficient fitting using convex optimization, which also guarantees that the solution is a global optimum.
Characteristics of the method
PI tomography is commonly used in experiments involving permutationally invariant states. If the density matrix obtained by PI tomography is entangled, then density matrix of the system, is also entangled. For this reason, the usual methods for entanglement verification, such as entanglement witnesses or the Peres-Horodecki criterion, can be applied to . Remarkably, the entanglement detection carried out in this way does not assume that the quantum system itself is permutationally invariant.
Moreover, the expectation value of any permutaionally invariant operator is the same for and for Very relevant examples of such operators are projectors to symmetric states, such as the Greenberger–Horne–Zeilinger state, the W state and symmetric Dicke states. Thus, we can obtain the fidelity with respect to the above-mentioned quantum states as the expectation value of the corresponding projectors in the state
The quantum fidelity of and can be bounded from below as
where is the projector to the symmetric subspace. For symmetric states, holds. This way, we can lower bound the difference knowing only
Links to other approaches
There are other approaches for tomography that need fewer measurements than full quantum state tomography. As we have discussed, PI tomography is typically most useful for quantum states that are close to being permutionally invariant. Compressed sensing is especially suited for low rank states. Matrix product state tomography is most suitable for, e.g., cluster states and ground states of spin models. Permutationally invariant tomography can be combined with compressed sensing. In this case, the number of local measurement settings needed can even be smaller than for permutationally invariant tomography.
Experiments
Permutationally invariant tomography has been tested experimentally for a four-qubit symmetric Dicke state, and also for a six-qubit symmetric Dicke in photons, and has been compared to full state tomography and compressed sensing. A simulation of permutationally invariant tomography shows that reconstruction of a positive semidefinite density matrix of 20 qubits from measured data is possible in a few minutes on a standard computer. The hybrid method combining permutationally invariant tomography and compressed sensing has also been tested.
References
Quantum mechanics
Tomography | Permutationally invariant quantum state tomography | [
"Physics"
] | 1,412 | [
"Theoretical physics",
"Quantum mechanics"
] |
72,615,273 | https://en.wikipedia.org/wiki/Weather%20of%202023 | The following is a list of weather events that occurred on Earth in the year 2023. The year saw a transition from La Niña to El Niño, with record high global average surface temperatures. There were several natural disasters around the world from various types of weather, including blizzards, cold waves, droughts, heat waves, wildfires, floods, tornadoes, and tropical cyclones. The deadliest weather event of the year was Storm Daniel, which killed over 5,900 people, with most of the fatalities coming from Libya. The costliest weather event of the year was Typhoon Doksuri, which caused $28.5 billion in damages in China, the Philippines and Taiwan. Another significant weather event was Cyclone Freddy, which became the longest lasting tropical cyclone on record, beating the previous mark of Hurricane John in 1994. The storm caused 1,434 fatalities, with most of the deaths coming from Malawi.
Deadliest events
Worst events
This is a list of weather events considered to be the most significant during 2023, in which reliable sources, surveys or academic assessments consider criteria such as, but not limited to: how impactful the event was, how deadly the event was, the impact on science, or other specific criteria. These events may be referred to as most important, most iconic, most signficiant, or the worst—but they are all considered key events in meteorology during the year.
Types
The following listed different types of special weather conditions worldwide.
Cold snaps and winter storms
In January, a cold snap in Afghanistan killed at least 166 people and more than 80,000 livestock. A national low temperature was set in Mohe City, China at , on January 23. Two days later, snow fell in Algeria for the first time in ten years.
Heat waves and droughts
Starting in April 2023, a record-breaking heat wave in Asia has affected multiple countries, including India, China, Laos and Thailand.
Tornadoes
An early-season tornado outbreak in the Southern United States was responsible for eight deaths and 53 injuries. On January 24, an EF3 tornado struck Deer Park, Texas, causing a tornado emergency. A storm complex in late February caused several tornadoes including a tornado that hit Cheyenne, Oklahoma, that killed one. A rare tornado near Taif, Saudi Arabia killed one person and injured one more. Two separate tornado outbreaks between March 24–March 27 and March 31–April 1 caused 58 deaths and two EF4 tornadoes in the US.
Tropical and subtropical cyclones
The first named tropical cyclone of the year was Cyclone Hale, which caused minimal damage and one death in New Zealand as an extratropical cyclone. Later in January, Cyclone Cheneso killed at least 33 people in Madagascar and left 20 missing. In addition, it damaged over 13,000 houses and 18 medical centers.
In February, Cyclone Freddy formed on February 4 and lasted until March 14, making it the longest lived tropical cyclone on record, surpassing Hurricane John of 1994, tracking across the entire Indian Ocean, the first to do so since Hudah and Leon-Eline in 2000. In addition, Freddy also recorded the highest accumulated cyclone energy of any tropical cyclone worldwide, at 87.01, surpassing the previous record of 85.26 by Hurricane Ioke in 2006. Freddy killed at least 1,434 people, and left 19 missing. In May, Cyclone Mocha formed and made landfall in Myanmar, killing 438 people and more than 101 missing. In June, Cyclone Biparjoy formed over the Arabian Sea and intensified into an extremely severe tropical cyclone, and made landfall in India, leaving at least 12 people dead.
Extratropical cyclones and European windstorms
Cyclone Helios which formed in early February brought recorded rain and humidity to Malta from 80 years. Luqa recorded rain with a total of 140.4 millimeters. meteo.it defined it as a Mediterranean tropical-like cyclone as it dissipated on February 11. Storm Otto, also known as Storm Ulf, brought high winds to the United Kingdom, Norway, and Germany. The highest wind gust was recorded in Cairngorms, UK, at 193 km/h (120 mph).
Wildfires
Over 100 wildfires have been confirmed in Alberta, Canada, and 13,000 people have been evacuated. The 2023 Hawaii wildfires killed over 110 people in the town on Lahaina, Hawaii.
Timeline
This is a timeline of weather events during 2023.
January
In January 2023, the National Oceanic and Atmospheric Administration documented 30 weather-related fatalities and 162 weather-related injuries in the United States and Territories of the United States.
November 2022–January 2023 – The rainy season in Malawi resulted in 42 fatalities from various severe weather incidents.
December 26–January 25 — 2022–2023 California floods: A series of atmospheric rivers impacts California, killing 22 people and causing at least 200,000 power outages in the state.
January 1 – A weather station in Abed, Denmark, measured the hottest temperature ever nationwide in the month of January, measuring , breaking the previous record of from January 10, 2005.
December 18, 2022 – February 5, 2023 — A shear line system caused flooding and landslides across the Philippines, killing 97 people with 25 more missing.
January 4 — Heavy rains caused a house to collapse in Matala, Angola, with two people being killed.
January 4–5 — Flooding and landslides in Buvaku, Democratic Republic of the Congo kills five people.
January 6–8 — Flooding and landslides in Indonesia kills five people.
January 10 — Flooding and landslides in Minas Gerais, Brazil kill six people.
January 10–17 — A cold snap in Afghanistan kills at least 166 people and more than 80,000 livestock. The coldest temperature recorded was in the province of Ghor.
January 12 — An early season tornado outbreak causes at least nine deaths in the Southern United States and several tornado emergencies.
January 12 — A lightning strike in HaOgen, Israel kills a person walking their dog.
January 13–16 — Heavy rains in Tijuana, Mexico, cause extreme flooding and a mudslide which killed two people.
January 14 — A flash flood in Medellín, Colombia killed two people and injured 25 others.
January 15 — Fatehpur, Rajasthan records a temperature of from a cold wave.
January 16 – Two EF1 tornadoes touch down in Iowa, the first tornadoes in the state in January since 1967.
January 16 — A landslide in Locroja District, Peru kills three people and leaves three others injured.
January 17 — An avalanche strikes Nyingchi, Tibet, killing 28.
January 18–19 — Flooding and landslides in Brazil kill 3 and leave 2 missing.
January 20 — Cyclone Cheneso leaves 33 dead and 20 missing in Madagascar.
January 27–February 6 — Heavy amounts of rain struck Auckland and the upper North Island in New Zealand causing massive flooding resulting in 4 deaths and 3 injuries
January 31 – Denmark had its wettest January on record, with a measurement of through the month, which beat the in January 2007 that previously held the record.
January 31–February 2 — An ice storm kills 10 people and causes 500,000 power outages across the Southern United States.
February
February 1 – of snow falls in New York City, becoming the latest date for first measurable snow there. Despite the minimal snow, a ground stop was still issued at LaGuardia Airport.
February 2 – Avalanche has buried a tourist near Mały Kościelec in Tatra Mountains, Poland. After a few days the men died.
February 3–4 – A cold wave briefly hit New England and Canada. The wind chill on Mount Washington, New Hampshire, drops to , marking the coldest wind chill ever recorded in the United States. The next day, the temperature of in Boston became the coldest day in the city since 1957.
February 5–7 – In the Mariano Nicolás Valcárcel District, 15 died from landslides that occurred after heavy rains.
February 4 – March 14 – Cyclone Freddy forms in the eastern Indian Ocean and makes landfall in Madagascar and Mozambique, becoming only the fourth storm to cross the entire Indian Ocean. Additionally, it was the longest lasting tropical cyclone on record with a duration of 5 weeks and 3 days, and holds the record for the highest accumulated cyclone energy (ACE) of any tropical cyclone of 87.01. 238 people die in Madagascar and Mozambique and over 1,200 people were killed in Malawi from extreme flooding and mudslides.
February 10 – Widespread record highs were broken across the Eastern United States, ranging from in Saint Johnsbury, Vermont, to in portions of North Carolina.
February 11–15 – Cyclone Gabrielle struck New Zealand particularly in the Gisborne and Hawkes Bay areas leaving 11 people dead while +3 are currently missing. Making it the most destructive cyclone in New Zealand since 1988.
February 16 – Record warm temperatures occur in the Eastern United States. Islip, New York, Bridgeport, Connecticut, Bedford, Massachusetts, and Newport, Rhode Island, all set record highs for the month of February. The record in Newport was broken by 6 °F (4 °C). At LaGuardia Airport, the low of tied for the warmest low on record, while Central Park observed a low of , the second warmest February low on record.
February 18–23 – Floods and mudslides kill at least 65 people across the state of São Paulo in Brazil.
February 21–28 – A major storm complex caused almost a million power outages throughout the United States, with Michigan being the most affected, with an ice storm that left at least one dead in Michigan when a power line fell on a volunteer firefighter.
March
March 1–3 – A storm complex containing both severe thunderstorms and heavy snowfall killed at least 13 people across the United States, including five in Kentucky, three in Alabama, two in Tennessee, one in Arkansas, and one in Mississippi.
March 6 – A landslide in Natuna Regency, Indonesia kills at least 50 people and four others remain missing.
March 7–20 – At least eight people were killed by Cyclone Yaku in Peru and Ecuador.
March 9–10 – Two people were killed and 9,400 were under evacuation orders as continuing atmospheric rivers brought heavy rains and flooding to parts of California.
March 15 – 16 deaths were reported as massive flash floods struck the Turkish provinces of Adiyaman and Sanliurfa, turning streets into rivers. These areas had been particularly hit hard by the past earthquakes.
March 21–22 – 5 died in California from high winds by a bomb cyclone that also caused two tornadoes, including one in Montebello.
March 22–25 – 14 died in the town Baardhere, Jubaland state, Somalia, when flash floods hit the area.
March 24–26 – 26 people were killed in a tornado outbreak in the Southern United States.
March 26 – 11 were killed and 67 were left missing by a landslide caused by heavy rains that occurred in Alausí, Ecuador.
March 31–April 1 – At least 26 people are killed in a tornado outbreak in the United States.
April
April 3 – Casper, Wyoming, saw its snowiest day on record, with of snow falling.
April 5 – An EF2 tornado hits the town of Glen Allen, Missouri, killing five people.
April 12–13 – Heavy rains affected Fort Lauderdale and South Florida, causing significant flooding.
April 14 – A temperature of at Windsor Locks, Connecticut, tied the state record for warmest April temperature. Additionally, a temperature of in Worcester, Massachusetts, became the earliest date for a ninety degree day.
April 19 – Tornadoes struck throughout the U.S. central plains, including a fatal EF3 tornado in Cole, Oklahoma. The outbreak lead to 3 fatalities.
April 21 – A significant tornado struck the Aung Myin Kone and Tadau villages near Myanmar's capital Naypyitaw, killing at least 8 people and injuring at least 128. At least 232 homes were also destroyed by the tornado.
April 22 - Gusty and strong winds in Pennsylvania lead to falling trees that killed 2 people.
April 27 — The hottest April temperature in Europe occurred, with the temperature in Córdoba, Spain at .
April 29 — A microburst in Texas caused “tens of millions of dollars” in damage.
May
May 3 – present — Floods in East Africa, especially in the DRC and Rwanda killed 440 and 129 respectively.
May 9 – Flooding caused a state of emergency in Auckland. 1 person was swept away by floodwaters in the Abbey Caves.
May 14–15 — Cyclone Mocha impacted Myanmar and Bangladesh, killing 438 people in total.
May 15 – Lightning kills one person and injured another in Texas.
May 16 – While in Cyclone Fabien, the Lu Peng Yuan Yu fishing vessel capsizes in the Indian Ocean. 16 of the 39 people on board have been confirmed dead.
May 16 – 17 — 17 people died and ten of thousands were left homeless in devastating floods in the Emilia-Romagna region of northern Italy.
May 18 –- Many daily record lows were set across the Northeastern United States, including Trenton, New Jersey, at , Montpelier, Vermont, at , Lebanon, New Hampshire, at , Bridgeport, Connecticut, at , Providence, Rhode Island, at , and Akron, Ohio, at . A temperature of became the coldest temperature so late in the year in Saranac Lake, New York, while Allentown, Pennsylvania, recorded their third latest freeze on record. This cold snap lead to several damaging frosts and freezes in Upstate New York.
May 19 – June 3 – Typhoon Mawar kills two people in Guam, one person in the Philippines, one person in Taiwan and two people in Japan.
May 23 – Two people were killed in a storm in Texas.
May 28 – A tourist boat sinks on Lake Maggiore in northern Italy, killing four.
May 29 – Shanghai records its hottest ever May temperature, at .
May 29 – Wildfires in Nova Scotia cause 16,000 to evacuate.
May 30 – A landslide in the southwestern Sichuan province, China, kills 19.
June
June 1–2 – Record heat affects portions of the Northeastern United States, with Burlington, Vermont, seeing a high of , the warmest temperature so early in the season there. The next day, daily records were set in Hartford and Philadelphia.
June 1 - Temperatures in Lapland, Finland reached , the coldest June temperature in the country.
June 2–4 – Floods in Haiti cause 51 deaths and injure 140 people. Additionally, over 13,500 homes were flooded and 820 were destroyed.
June 6–19 – Cyclone Biparjoy becomes the longest-lived cyclone in the Arabian Sea and kills 12 people in Gujarat.
June 8–9 – Windstorms and floods in Iran kill seven and leave 59 injured.
June 10 – Heavy rains in northeast Pakistan kills 25 and leaves 145 injured.
June 14–19 – A widespread tornado outbreak sequence leaves five dead and 120 injured
A low-end EF3 tornado damages or destroys nearly 200 homes in Perryton, Texas.
In Jasper County, Mississippi, over a dozen buildings were destroyed and one person was killed by an EF3 tornado.
June 17–18 – Floods and landslides in Nepal kill at least six and leave 28 missing.
June 20 – Two Texas cities broke all-time record high temperatures, with San Angelo reaching and Del Rio reaching . Air conditioning pushed ERCOT power demand to a record 81.2 GW.
June 20–26 – A second widespread tornado outbreak sequence across the United States leaves over 100 injured and eight dead.
An EF3 tornado in Matador, Texas, kills four people and destroys over ten buildings.
An EF2 tornado in Martin and Dubois County, Indiana, leaves one dead and another person injured.
At George Bush Intercontinental Airport, a record gust of was observed, surpassing the airport's previous highest gust of during Hurricane Ike.
June 22 – July 6 – Monsoon rains in Pakistan kill 55 people, including at least eight children.
June 25 – Ten people are killed from lightning strikes in Punjab province, Pakistan.
June 27 – Flash flood induced landslides in the Miansi and Weizhou townships in Sichuan province, China, result in four deaths and three missing people.
June 29 – Authorities in Mexico have said that within the past two weeks, over 100 people have died from heat related deaths as temperatures have came close to .
June 30 – Heavy rain and a tornado in KwaZulu-Natal, South Africa leaves at least seven people dead another seven missing.
July
July 1–7 – The World Meteorological Organization find that the first week of July was the hottest week recorded during an El Niño which was worsened by climate change. The record was broken twice and equaled once in that week.
{| class="wikitable"
! Date !! Average global temperature
|-
| align="right"|Monday, July 3 ||
|-
| align="right"|Tuesday, July 4 ||
|-
| align="right"|Wednesday, July 5 ||
|-
| align="right"|Thursday, July 6 ||
|}
July 3–present – Monsoon rains cause record-breaking and destructive floods in North India, killing over 100.
July 9 – The capital of India, New Delhi, receives its wettest July day in over 40 years, receiving of rain.
July 19 – A landslide in Raigad kills at least 16 people with another 100 feared dead under debris.
July 9–16 – Flash flooding in the Northeastern United States kills at least eight people and leaves two children missing.
July 10 – Torrential rain in southern Japan cause landslides that kill three people.
July 13–18 – Tropical Storm Talim leaves three dead across the Philippines and Southern China.
July 16 - Monsoon flooding in South Korea kill at least 41 people and 9 missing.
July 17 – Torrential rains cause a landslide in Quetame, Colombia leaves 14 dead.
July 18 – Phoenix recorded their warmest ever low temperature on record, at .
July 19 – A severe storm sweeps through the western Balkans, killing five people.
July 19–29 – Typhoon Doksuri causes at least 87 deaths and over $2 billion in damages.
July 27 – The MB Aya Express capsizes in the Philippines, killing 27.
July 27–29 – Record-breaking floods in China result in 30 deaths and $2 billion in damages.
July 22 – Another severe storms hits Serbia killing three.
July 24- Lightning in Upstate New York kills one person.
July 25 – A nighttime storm in Lombardy, Italy leaves four dead.
July 27 – August 11 – Typhoon Khanun kills at least two people in Okinawa.
July 30 – In Mari El, Russia, severe storms leave ten dead at a campsite.
August
August 3–23 – Floods in Carinthia and Slovenia kill seven people.
August 3 – 32 people are killed and one is left missing after a landslide in Shovi, Georgia.
August 4-8 - Severe storms, mainly in the Eastern United States kill two people and result in over a million power outages.
August 11 – Floods in Myanmar kills five.
August 12 – A landslide in Xi'an, China, kills 21 people and leaves six missing.
August 12 – Four people are killed by lightning strikes in separate incidents in Yemen.
August 16–22 – Hurricane Hilary kills two people in Mexico and becomes the first tropical cyclone to bring tropical storm force winds to California since 1997. Additionally, four states in the United States break tropical cyclone rainfall records.
August 20 – September 1 – Hurricane Franklin kills two people and leaves one missing in the Dominican Republic.
August 22 – September 3 – Typhoon Saola kills one person in the Philippines.
August 24–31 – Hurricane Idalia kills nine people in the Eastern United States after landfall in Florida.
August 27 – September 6 – Typhoon Haikui leaves two dead in Taiwan and China.
August 28–30 – Heavy rains in Tajikistan kills 21 people.
August 28 – Severe wind gusts strikes a thermal spa in Podhájska, Slovakia, injuring one person. Wooden booths at the spa were obliterated and swept away, trees were uprooted, and a camper was overturned. Tomas Pucik, a meteorologist and forecaster with the European Severe Storms Laboratory (ESSL) conducted a scientific study on the wind gusts. The study rated the damage caused IF1.5 on the International Fujita scale, with winds estimated between .
September
In September 2023, 20% of the earth's surface experienced new record high temperatures, the highest percentage of any month since the start of records in 1951.
September 2 - Flooding in the Southwestern United States kills one person at the Burning Man festival.
September 6 – A cyclone in Rio Grande do Sul causes floods that kill 21 people.
September 7–8 – The remnants of Typhoon Haikui combined with a low pressure trough cause widespread flooding in Hong Kong, killing four and injuring nearly 150.
September 4–11 – Storm Daniel causes catastrophic flooding across Libya and Southeast Europe, killing near 7,000 people and leaving 10,000 missing. Additionally, flooding in Greece is responsible for $2.14 billion in damages.
September 11 - September 2023 northeastern U.S. floods - The city of Leominster, Massachusetts, declares a state of emergency after rain up to brought unprecidented flash flooding.
September 19 – Three tornadoes, one rated as an EF3 tornado, hits Jiangsu in China. 10 people were killed.
September 21–22 – Flooding hits New Zealand South Island causing a state of emergency in Queenstown and Southland with Queenstown recording its wettest day in 24 years and Wānaka recording its wettest day in 17 years.
September 25 – Floods in Mexico and Guatemala kill 13 people and leave 22 missing.
September 24–25 — Floods in the Western Cape province of South Africa kill at least 11 and leave over 80,000 without electricity.
September 28–30 - New York City declares a state of emergency during major flooding in the city.
October
The month of October was the warmest October ever recorded.
October 4 – Monthly record highs were set in Burlington, Vermont, and Syracuse, New York, with temperatures of and .
October 4–5 – Heavy rains in Sikkim causes the South Lhonak Lake to outburst, killing at least 74 people in Sikkim and West Bengal.
October 6 – Six people are killed from rain-induced mudslides in Sri Lanka.
October 8 – Landslides in Yaoundé, Cameroon leaves 27 dead and left 50 injured.
October 8 – Bush fires in Darling Downs, Australia kills two people.
October 17–23 – Hurricane Norma kills three people in Sinaloa, Mexico.
October 19–27 – Cyclone Lola becomes the earliest Category 5 cyclone in the South Pacific region and kills two in Vanuatu.
October 22–25 – Hurricane Otis makes a devastating landfall near Acapulco, Mexico, as a Category 5, the strongest ever Pacific hurricane at landfall. At least 50 people are killed, with some estimates going up to 350, and $16 billion in damages are done.
October 28 – November 6 – Tropical Storm Pilar leaves two dead in El Salvador.
November
November 19 – Flooding in the Dominican Republic kills 21 people.
November 20 – Flooding in Turkey and Bulgaria kills nine people and leaves eleven crew members on the Kafkametler missing.
November 24-28 - A winter storm in the United States kills 4.
November 27 – A snowstorm in Ukraine and Moldova kills eight people and injures another 29.
December
December 2–18 – Cyclone Jasper becomes the wettest tropical cyclone in Australian history, with of rain falling in Northern Queensland.
December 3 – Flooding and landslides in Tanzania kills 47 people and injures another 85.
December 5 – An atmospheric river in the Pacific Northwest kills one person.
December 9-10 - A tornado outbreak kills 6 people in Tennessee.
December 14 – Over 500 people are injured in a subway collision in Beijing, partially due to slippery tracks in a winter storm.
December 16 – A severe thunderstorm in Bahía Blanca, Argentina kills 13 people.
December 18 – A storm in the Northeastern United States kills four people and causes over 600,000 power outages.
December 26 – 22 people are killed in floods in the Kasaï-Central provence of the Democratic Republic of the Congo.
December 27 – Thunderstorms in Eastern Australia kills 10 people.
December 29 – 20 people are killed in landslides in the South Kivu region of the Democratic Republic of the Congo.
December 30 - Flash flooding in KwaZulu-Natal, South Africa, kills 21.
December 31 - Tropical Storm Alvaro forms west of Madagascar, bringing heavy rain and strong winds to the island, then persisting into 2024.
Space weather
January 9 – An X1.9-class solar flare causes a widespread radio blackout across South and Central America. The active region that produced the solar flare also produced an X1.2-class solar flare on January 5.
December 14 – An X2.8-class solar flare, the largest since September 2017, causes an R2 radio blackout across South and Central America.
December 31 – An X5.0-class solar flare causes an R3 radio blackout over the Pacific.
Events in meteorology
January 9 – Perseverance provides the first ever detailed weather report on Mars.
See also
Weather of 2022
Weather of 2021
Notes
References
Weather by year
Weather-related lists
2023-related lists
2023 meteorology | Weather of 2023 | [
"Physics"
] | 5,171 | [
"Weather",
"Physical phenomena",
"Weather by year",
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63,955,669 | https://en.wikipedia.org/wiki/Universal%20Stylus%20Initiative | The Universal Stylus Initiative (USI) is a non-profit alliance of companies promoting a technical standard for interoperable active pen styluses on touchscreen devices such as phones, tablets, and computers.
It defines a two-way communication protocol between the stylus and the computer and allows the stylus to remember user preferences for ink color and stroke. It support 9-axis inertial measurement.
Products started coming to market in 2019 including one stylus and several Chromebooks from different manufacturers. By 2019, there were over 30 members, including Google and 3M, but some major players like Apple and Microsoft had not joined. As of 2022, the promoters include Google, Intel, Lenovo, Samsung, and Synaptics. Dell, Sharp, and Wacom are contributors.
While USI promotes itself as an open standard, access to detailed specifications is restricted to paying members.
History
USI was launched on April 23, 2015, by a group of prominent OEMs, stylus and touch controller manufacturers.
September 22, 2016: Release of the USI 1.0 Stylus and Device Specification
September 26, 2019: Announcement of the first 14 companies with products using the USI 1.0 Specification
June 10, 2020: Launch of the USI active stylus certification program
February 28, 2022: Release of USI Version 2.0 specification
Features
USI 1.0
Two-way communication protocol
Support for multiple simultaneous styluses on a single device
Pressure sensitivity (up to 2048 levels in USI 1.0)
Button presses and eraser functionality
Tilt detection
USI 2.0
NFC wireless charging capability
Support for in-cell display panels
Expanded tilt functionality
See also
Stylus (computing)
Digital pen
Pen computing
Active pen
Wacom
Surface Pen
Apple Pencil
Computer mouse
Human–computer interaction
References
External links
Non-profit organizations based in Massachusetts | Universal Stylus Initiative | [
"Technology"
] | 378 | [
"Computing stubs",
"Computer hardware stubs"
] |
63,957,187 | https://en.wikipedia.org/wiki/North%20American%20Numbering%20Council | The North American Numbering Council is an advisory committee of the Federal Communications Commission (FCC) of the United States, chartered in 1995. Its function is to develop and recommend efficient and fair administrative procedures in the administration of the North American Numbering Plan (NANP), including telephone numbering plan policy and technical implementation. The council is headed by a Designated Federal Officer appointed by the FCC. It is renewed on a two-year term schedule pursuant to the Federal Advisory Committee Act, and meets approximately four times per year. Its work is structured and conducted in working groups. The committee reports to the FCC via the Wireline Competition Bureau.
Founding
The original charter of the North American Numbering Council was filed with the United States Congress on October 5, 1995. The charter is renewed periodically in accordance with the provisions of the Federal Advisory Committee Act (FACA). The council held its first meeting on October 1, 1996.
Purpose
The North American Numbering Council advises the Federal Communications Commission in an oversight capacity over telephone numbering plan issues. Through consensus decisions of its members, the council recommends procedures, policies, and technical means for efficient numbering administration, impartial to any telecommunication industry interest group. The council develops policy for numbering issues and initially resolves disputes. It provides guidance to the North American Numbering Plan Administrator (NANPA).
Working groups
The North American Numbering Council conducts several working groups in assistance of its advisory function to the FCC.
As of 2020, the following working groups are established.
Numbering Administration Oversight
Call Authentication Trust Anchor
Toll Free Assignment Modernization
Nationwide Number Portability
Interoperable Video Calling
See also
Number Portability Administration Center
Telecommunications Act of 1996
Communications Act of 1934
References
External links
North American Numbering Council website
Wireline Competition Bureau
Federal Communications Commission
North American Numbering Plan
Telephone numbers | North American Numbering Council | [
"Mathematics"
] | 351 | [
"Mathematical objects",
"Numbers",
"Telephone numbers"
] |
63,960,019 | https://en.wikipedia.org/wiki/Hosh%20%28architecture%29 | A hosh (), or hawsh, is a courtyard in some traditional residential complexes in the Arab world. It represents the center of the housing structure.
References
Courtyards
Islamic architecture
Islamic architectural elements
Arabic architecture
Ottoman architecture
House types
Architecture in Syria
Architecture in the State of Palestine
Architecture in Lebanon | Hosh (architecture) | [
"Engineering"
] | 61 | [
"Architecture stubs",
"Architecture"
] |
63,960,965 | https://en.wikipedia.org/wiki/Serum%20B-cell%20maturation%20antigen | Serum B-cell maturation antigen (sBCMA) is the cleaved form of B-cell maturation antigen (BCMA), found at low levels in the serum of normal patients and generally elevated in patients with multiple myeloma (MM). Changes in sBCMA levels have been found to correlate with a MM patient’s clinical status in response to treatment.
Role in biology
BCMA is a member of the tumor necrosis factor receptor family, expressed on the cell surface of maturing plasma cells and is involved in supporting normal survival of long-lived plasma cells, production of antibodies, and class switching of immunoglobulins. In MM, BCMA promotes the proliferation and survival of MM cells and is associated with the immunosuppression which is the hallmark of MM. The BCMA molecule is the receptor for APRIL (a proliferation-inducing ligand) and BAFF (B-cell activating factor, also known as BLyS). The binding of APRIL and BAFF to the membrane bound form of BCMA stimulates B-cell proliferation and antibody production. The membrane bound BCMA can be cleaved by gamma secretase, resulting in sBCMA, and released into the blood.
Clinical significance
Serum BCMA is found at low levels in the serum or plasma of normal patients and is generally elevated in patients with MM. sBCMA levels have been found to correlate with the severity of myeloma disease and shown to be predictive of response to therapy. Progression free survival (PFS) and overall survival (OS) in MM patients have also correlated with levels of sBCMA. Changes in sBCMA also correlate with changes in disease status among MM patients. In addition to MM, sBCMA also appears to correlate with disease progression in monoclonal gammopathy of undetermined significance (MGUS), smoldering myeloma (SMM) and in chronic lymphocytic leukemia (CLL).
As a biomarker
When BCMA is cleaved from the cell membrane of plasma cells by gamma secretase, a ubiquitous intramembranous protease enzyme, it is solubilized in the serum, where it can accumulate and bind to various targets including BAFF and APRIL. Patients with MM generally have higher levels of sBCMA. Solubilized BCMA can sequester BAFF, preventing it from signaling B cells, resulting in reduced polyclonal antibody levels in patients with MM. In multiple studies, sBCMA levels have been found to correlate with the severity of myeloma. Notably, sBCMA levels are predictive of response to therapy, PFS and OS. In addition, changes in sBCMA predict changes in clinical status more rapidly than conventional markers that are used to track MM patients. For this reason, the biomarker has been used in diagnostic evaluation of myeloma and other B-cell disorders.
In therapeutics
sBCMA can bind to anti-BCMA antibodies used as therapeutics in treating MM. It has been shown that the high levels of BCMA present in the serum of MM patients can inhibit the effectiveness of BCMA-directed therapy. For this reason, the gamma secretase enzyme has been the target of some recent drug therapies. These drugs aim to inhibit the action of the gamma secretase enzyme, thus both increasing the density of BCMA on the MM cell while at the same time lowering the levels of sBCMA in the blood and allowing anti-BCMA antibodies to more effectively bind to the target cells.
In diagnostics
sBCMA has been measured and evaluated using enzyme-linked immunosorbent assays (ELISAs) in numerous investigational studies of MM related B-cell diseases. Although still investigational, sBCMA appears to be a novel biomarker to track MM such as M-protein and serum Free Light Chain (FLC). All three biomarkers are generally elevated on initial evaluation of MM, tend to increase as the severity of disease increases, and decrease as patients respond to therapy.
Because levels of the biomarkers appear to correlate with disease severity, they have been used in diagnostics as a way to monitor patients’ disease and evaluate response to therapy. Preliminary investigations have indicated that sBCMA, unlike M protein or FLC, is independent of the patient’s kidney function, and may offer an advantage to monitoring those patients.
Additionally, sBCMA is expressed in non-secretory MM, a subset of MM in which patients do not express high enough levels of M protein or SFLC to be accurately followed using these two biomarkers. These patientsgenerally need to undergo bone marrow biopsies frequently to evaluate their status. The sBCMA biomarker may offer an alternative means to evaluate this subset of patients.
In related diseases
Levels of sBCMA appear to progressively increase along the spectrum of plasma cell-related disorders. Serum BCMA is increased in patients with active MM compared with healthy controls. Levels of sBCMA were determined in 196 healthy subjects and showed a right-tailed distribution with a median value of 37.51 ng/mL with a standard deviation of 22.54 ng/mL (range 18.78 -180.39 ng/mL). Among patients with MM, sBCMA levels correlated with the percentage of malignant cells, giving rise to the concept that sBCMA may reflect a patient’s tumor burden.
Levels of sBCMA among patients with MM were elevated when compared with healthy controls (P<0.0001) and those with monoclonal gammopathy of undetermined significance (MGUS) (P=0.0157). Furthermore, sBCMA levels were significantly higher among patients with smoldering multiple myeloma (SMM) and untreated active MM patients than healthy donors (P<0.0001).
In a retrospective study of MGUS and SMM patients, the highest levels of sBCMA were observed among patients with SMM who progressed to MM, intermediate levels were seen in patients with MGUS who progressed to MM, and lowest baseline levels were found among patients with MGUS who did not progress to MM. The change in sBCMA over time was lowest in the non-progressing patients with MGUS.
Sometimes, MM patients show undetectable levels of monoclonal immunoglobulin (M protein) in the serum or urine. For this reason, these patients are generally monitored using bone marrow biopsies and PET CT scans. It has been found, however, that sBCMA can be reliably measured in these patients, and correlates well with disease activity and changes in their PET scans and the percentage of bone marrow plasma cells during the course of disease.
In response to treatment
sBCMA has been investigated among MM patients undergoing numerous treatment regiments. Changes in sBCMA levels were found to correlate with changes in an individual patient’s clinical status in response to treatment for MM.
Additionally, sBCMA levels were significantly higher among patients with progressive disease than in patients with disease responsive to treatment (P=0.0038). Interestingly, sBCMA levels correlated with response to treatment, independent of the type of treatment.
Among patients starting new treatment, changes in sBCMA levels from baseline to one week later (cycle 1 day 8) were found to predict PFS, with >25% increase or decrease in serum BCMA levels on cycle 1 day 8 indicating a much shorter or longer time on treatment, respectively.
As predictor of progression free survival and overall survival
Serum BCMA levels have been reported to predict both PFS and overall survival (OS) in MM.
In a study by Ghermezi et al., sBCMA levels were predictive of PFS and OS among patients with MM. PFS was significantly longer for patients with sBCMA levels below the median (326.4 ng/mL) versus those with levels above the median (median, 9.0 vs 3.6 months; P=0.0006). Similarly, OS was significantly longer among those with sBCMA levels below the median compared with those above (median, 155 vs 96 months; P =0.0108).
MM patients with sBCMA levels above the median had significantly shorter survival compared with patients with levels below the median concentration (P=0.0014). Patients in the highest quartile showed a markedly shortened survival compared with the remainder of the patients (P=0.0003).
In a prospective Phase 1 trial of sBCMA to predict clinical outcomes among patients with relapsed or refractory MM treated with lenalidomide, ruxolitinib and methylprednisolone, baseline sBCMA levels were found to be predictive of PFS. Specifically, patients with a baseline sBCMA level in the highest quartile (range, 414.7 – 1655.1 ng/mL) had a significantly shorter PFS than those in the lowest three quartiles (range, 10.3 – 318.2 ng/mL; median PFS: 1.12 vs. 6.64 months; P=0.006). In the same prospective Phase 1 trial, changes in sBCMA during the first cycle study treatment accurately predicted patients later best response. Notably, changes in sBCMA occurred more rapidly than changes in either M-protein or FLC.
Studies to further investigate the role of sBCMA in predicting OS and PFS are ongoing.
References
Genes on human chromosome 16
Protein domains | Serum B-cell maturation antigen | [
"Biology"
] | 1,989 | [
"Protein domains",
"Protein classification"
] |
63,962,424 | https://en.wikipedia.org/wiki/Lutetium%28III%29%20fluoride | Lutetium(III) fluoride is an inorganic compound with a chemical formula LuF3.
Production
Lutetium(III) fluoride can be produced by reacting lutetium oxide with hydrogen fluoride, or reacting lutetium chloride and hydrofluoric acid:
It can also be produced by reacting lutetium sulfide and hydrofluoric acid:
(x = 0.9)
Lutetium oxide and nitrogen trifluoride react at 240 °C to produce LuOF. A second step happens below 460 °C to produce LuF3.
References
Lutetium compounds
Fluorides
Lanthanide halides | Lutetium(III) fluoride | [
"Chemistry"
] | 132 | [
"Inorganic compounds",
"Fluorides",
"Inorganic compound stubs",
"Salts"
] |
63,964,488 | https://en.wikipedia.org/wiki/Rapid%20voltage%20change | A rapid voltage change or RVC is one of the power-quality (PQ) issue related to voltage disturbance. "According to IEC 61000-4-30, Ed. 3 standard, RVC is defined as "a quick transition in root means square (r.m.s.) voltage occurring between two steady-state conditions, and during which the r.m.s. voltage does not exceed the dip/swell thresholds." Switching processes such as motor starting, capacitor bank on/off, load switching, or transformer tap-changer operations can all create RVCs. Moreover, they can also be induced by sudden load variations or by disturbance in power output from distributed energy sources such as solar or wind power system. The main known effect of rapid voltage changes is light flicker, but other non-flicker effects also have been reported.
Rapid voltage change effect
The RVC voltage disturbance level is not as big as sag / dip and swell. While RVC events generally are not destructive for electronic equipment, it can be annoying for final users as they may influence light flicker.
References
Electronics
Voltage stability
Electric power | Rapid voltage change | [
"Physics",
"Engineering"
] | 232 | [
"Physical quantities",
"Electrical engineering",
"Power (physics)",
"Electric power",
"Voltage",
"Voltage stability"
] |
63,965,880 | https://en.wikipedia.org/wiki/Zero%20dynamics | In mathematics, zero dynamics is known as the concept of evaluating the effect of zero on systems.
History
The idea was introduced thirty years ago as the nonlinear approach to the concept of transmission of zeros. The original purpose of introducing the concept was to develop an asymptotic stabilization with a set of guaranteed regions of attraction (semi-global stabilizability), to make the overall system stable.
Initial working
Given the internal dynamics of any system, zero dynamics refers to the control action chosen in which the output variables of the system are kept identically zero. While, various systems have an equally distinctive set of zeros, such as decoupling zeros, invariant zeros, and transmission zeros. Thus, the reason for developing this concept was to control the non-minimum phase and nonlinear systems effectively.
Applications
The concept is widely utilized in SISO mechanical systems, whereby applying a few heuristic approaches, zeros can be identified for various linear systems. Zero dynamics adds an essential feature to the overall system’s analysis and the design of the controllers. Mainly its behavior plays a significant role in measuring the performance limitations of specific feedback systems. In a Single Input Single Output system, the zero dynamics can be identified by using junction structure patterns. In other words, using concepts like bond graph models can help to point out the potential direction of the SISO systems.
Apart from its application in nonlinear standardized systems, similar controlled results can be obtained by using zero dynamics on nonlinear discrete-time systems. In this scenario, the application of zero dynamics can be an interesting tool to measure the performance of nonlinear digital design systems (nonlinear discrete-time systems).
Before the advent of zero dynamics, the problem of acquiring non-interacting control systems by using internal stability was not specifically discussed. However, with the asymptotic stability present within the zero dynamics of a system, static feedback can be ensured. Such results make zero dynamics an interesting tool to guarantee the internal stability of non-interacting control systems.
References
Differential equations | Zero dynamics | [
"Mathematics"
] | 407 | [
"Mathematical objects",
"Differential equations",
"Equations"
] |
63,966,025 | https://en.wikipedia.org/wiki/Polar%20diagram%20%28sailing%29 | A polar diagram, or polar plot, is a graph that shows a sailboat's potential speed over a range of wind speeds and relative wind angles. It normally consists of the right side of a line chart with the radius representing the yacht speed and the angle representing the wind direction blowing from top to bottom. Several lines are normally drawn on the chart representing wind speed. To identify how fast a yacht could potentially go you select a particular wind speed curve and particular wind angle. Refer to the graph to the right for an example.
Polar diagrams are normally specific to a particular sailboat design and are created by the yacht designer. Polar diagrams can also be created using a velocity prediction program or by a range of computer programs including iPolar and iRegatta.
See also
Forces on sails
External links
ORC Sailboat Data a large database of polar diagrams maintained by the Offshore Racing Congress
References
Naval architecture
Sailing | Polar diagram (sailing) | [
"Engineering"
] | 181 | [
"Naval architecture",
"Marine engineering"
] |
63,966,709 | https://en.wikipedia.org/wiki/Computus%20clock | A computus clock is a clock equipped with a mechanism that automatically calculates and displays, or helps determine, the date of Easter (and other dependent dates of moveable Church feasts). A computus watch carries out the same function.
Background
The movement of a computus clock provides and/or calculates astronomical and calendar information according to the tradition that Easter Sunday is the first Sunday after the first full moon (Paschal or ecclesiastical full moon) on or after the spring equinox (21 March), and Easter Sunday should not occur on the same day as the Jewish calendar date Nisan 15th, the first day of Passover week. In early Christianity, the Easter date was calculated each year and announced by the Pope. The later need for Christian clergy living in different territories to be able to calculate the Easter date for themselves forced attempts to establish clear rules for the Easter date calculation and finally the algorithms for this.
The determination of the Easter date requires calculating astronomical and calendar cycles – the annual motion of the Sun round the celestial sphere, the evolution of the phases of the Moon, the cycle of the days of the week, particularities of calendars and some agreements like the date of the so-called ecclesiastical equinox., designated as March 21, irrespective of the actual astronomical observation by the Church of Alexandria in the beginning of the 4th Century.
Specific astronomical data which may be incorrect, misinterpreted or location dependent, were eliminated from the Easter date calculation by the invention of special paschal functions – “letters” and “numbers”. They include the “golden number” (which gives the dates of all the new moons for the year in a 19-year Metonic cycle), the solar cycle (the 28-year cycle of the Julian calendar and 400-year cycle of the Gregorian calendar with respect to the week), the epact (the age of the Moon in days on a certain date), the dominical letter (used to determine the day of the week for particular dates) and the indiction (the number of a given year in a fifteen-year period). The computations after the Gregorian reform of 1582 should also take into account additional corrections necessary due to particularities of the Gregorian calendar, notably the solar equation (taking into account some non-leap century years) and the lunar equation (for correction of the Metonic cycle)
The term “computus” as the description of the Easter date computation was proposed in 725 by the English Benedictine monk Bede in his treatise “De temporum ratione” (“The Reckoning of Time”).
Alexandrian computus, based on rules established by the Church of Alexandria, was universally used from the beginning of the 8th century until the Gregorian calendar reform of 1582. The Roman Catholic Church has used the Gregorian calendar, and accordingly Gregorian computus, to calculate the dates of Easter since 1583. The Gregorian computus was later adopted by most Protestant churches – between 1753 and 1845 – while most Eastern Churches, including the majority of Eastern Orthodox Churches and Non-Chalcedonian Churches continued to produce the Easter date computation based on the Julian calendar (Alexandrian computus), although both had and indeed still have some complications, described in detail in dedicated studies.
The Alexandrian computus gives a 532-year period of Easter dates. Given that all possible dates on which Easter can occur lie within a 35-day period – from March 22 to April 25 (old style dates) or from April 4 to May 8 (new style dates) – the Alexandrian Easter algorithm is equivalent to 18620 options (532 x 35), showing the complexity of computus implementation in a compact clockwork. The Gregorian Easter algorithm gives even more options due to the fact that the duration of the period is 5,700,000 years (70,499,183 lunar months or 2,081,882,250 days).
The German mathematician Karl Gauss presented a computus algorithm in 1800 and finalized it in 1807 and 1811. Gauss’ algorithm is considered to be the most commonly used and although it was intended for calculating the Easter date for the Gregorian calendar, it is also valid for the calculation of the Easter date for the Julian calendar.
The indication of the date of the upcoming Easter is one of the rarest astronomical functions of mechanical clocks and watches due to the high levels of complexity involved. Moreover, there is significant discrepancy in computus algorithms due to the differences of the Julian and Gregorian calendars (Easter controversy).
The obvious difficulties in implementing computus algorithms in clockwork explain the fact that in the entire history of mechanical clocks and watchmaking, just a few examples of computus clocks and watches have been made.
Computus clock types
Tabular computus clocks
Clocks with a tabular computus provide the indication of special paschal (ecclesiastical) functions without the automatic counting of the date of Easter, so the date should be determined by the paschal table with the use of indications - the golden number, the solar cycle, the epact, the dominical letter, and the indiction – all or some of which, may be with the addition of other indications.
It is believed the first Easter function in a mechanical clock was created by the Italian physician, astronomer and mechanical engineer Giovanni Dondi dell'Orologio from Padua. He built his complicated astronomical clock “Astrarium” from 1348 to 1364. The clock has not survived, but the design and construction were described in detail by Dondi in his manuscripts and provided enough material for modern clockmakers to build reconstructions. While few reconstructions have been made, one example of Dondi's computus can be found in the Smithsonian Institution (Washington DC, USA).
Dondi's computus was based on a device with a wheel drive and three chain indicators of the 7980-year Julian period. The first chain with 28 links was used to indicate the dominical letter and the 28-year solar cycle, the second chain with 19 links was used to indicate the golden number, and the third chain was used for the 15-year cycle of indiction. The computus was set under the date display ring, which was designed for a 365-day year (in the leap year, Giovanni de Dondi intended to stop the clock for one day).
A tabular computus with indications of the dominical letter, the epact, the 28-year solar cycle, the golden number and the indiction was made by the French clockmaker Auguste-Lucien Vérité in his monumental astronomical pendulum clock of Besançon Cathedral (France). Built from 1858 to 1860, the clock's epact dial has an additional indication of Easter dates for a period of 19 years on cartouches, which should be replaced or repainted every 19 years by the keeper of the clock.
Ecclesiastical functions of the 28-year solar cycle, the Julian epact, the Gregorian epact, the Julian dominical letter, the Gregorian dominical letter, the golden number and the indiction were implemented by the Swiss watchmaker Albert Billeter in his supercomplicated monumental “Ivanovo” Universal Clock, which he made in 1873 in Paris and which is kept in Ivanovo Museum of Industry and Arts (also known as the D.G.Burylin Museum, Ivanovo, Russia).
The French clockmaker Paul Pouvillon included a computus module in his complicated astronomical clock with orrery, made from 1918 to at least 1939 (and probably into the 1960s). The module has a single indicator of the Gregorian Easter date in a window with a disc underneath, stamped with the Easter dates for the 19-year period from 1946 to 1964. The moveable feast's indicator is set on the tellurium dial, and its adjustment to correct the dates should be made manually. The computus module has 6 ecclesiastical functions – the 28-year solar cycle, the Gregorian epact, the Gregorian dominical letter, the golden number, the indiction and the indication of the day of the week of January 1 of the next year, so the computation of the Easter date may be provided with the help of the ecclesiastical functions even for the years after 1964, when the original Easter date disc is no more valid, as noted during restoration works in 2011–2012.
Indications of the 28-year solar cycle, golden number and indiction were used by the Norwegian clockmaker and inventor Rasmus Jonassen Sørnes in his complicated astronomical pendulum clock No.4 (Sørnes No.4), built from 1958 to 1966.
Computus clocks with automatic mechanical counting devices
The most complicated type of computus clock is rather a kind of mechanical computer making automatic Easter calculations based on ecclesiastical indications at the beginning of a given year.
The first computus clock with a fully automatic action was made by the French clockmaker and inventor Jean-Baptiste Schwilgué, the author of the third astronomical clock of Strasbourg Cathedral (Strasbourg astronomical clock), between 1838 and 1843. In 1816 he invented and built the first prototype of his mechanical computus “Comput ecclésiastique”, and in 1821 he made the final calculations and design of his device, acting as a Gregorian computus. Schwilgué embedded his computus into the astronomical clock of Strasbourg Cathedral, where it continues to operate to this day. It includes 5 ecclesiastical functions – the 28-year solar cycle, the Gregorian epact, the Gregorian dominical letter, the golden number and the indiction, with the addition of a 4-digit Gregorian year indicator. At the start of each year, the computus changes the indications of the dates of Easter and moveable feasts on the annual calendar ring of the main dial in the central lower part of the clock.
The Danish clockmaker Jens Olsen, while visiting Strasbourg in 1897, was inspired by Jean-Baptiste Schwilgué's astronomical clock of Strasbourg Cathedral and in 1924 he completed a separate computus module (“Comput ecclésiastique”), that has certain similarities to Schwilgué's “Comput ecclésiastique”. Later, in 1928, Jens Olsen made the calculations of a supercomplicated astronomical computus clock. The clock, known as “World Clock” (in Danish, “Verdensuret”), was finished in 1955, 10 years after his death, by his colleague Otto Mortensen, who took over the project. The clock is displayed in Copenhagen's Rådhus (City Hall). The computus of Jens Olsen's World Clock has 5 ecclesiastical functions – the Gregorian dominical letter, the Gregorian epact, the 28-year solar cycle, the indiction and the golden number, while the clock is also equipped with a Gregorian perpetual calendar indicating the date, day of the week, month and the year in four digits. Beneath the ecclesiastical dials there is an unparalleled tabular calendar showing the dates and days of the week of all 12 months of the year, the phases of the Moon for every date, and the dates of Easter and other moveable feasts. The computus and Gregorian perpetual calendar automatically switch at midnight at New Year to calculate the calendar for the following year.
The French clockmaker also took his inspiration from the works of Jean-Baptiste Schwilgué and his astronomical clock of Strasbourg Cathedral. Vachey spent thirty years – from 1938 to 1968 – building his supercomplicated astronomical computus clock. The computus of the clock has 5 ecclesiastical functions – the Gregorian dominical letter, the Gregorian epact, the 28-year solar cycle, the indiction and the golden number. The clock is also equipped with a dial for 6 moveable feasts and a perpetual calendar with date, day of the week, month and bissextile year indicators.
Computus clock with opto-mechanical indication
The Easter date in a computus clock with an opto-mechanical indication is shown by the superposition of the matching holes of perforated discs. This type of display has also been used to indicate the date of Orthodox Easter. An opto-mechanical Easter date display was built into this “Easter of Christ Computus Clock” clock of 2005, the first computus clock of this type invented and made by Russian watch- and clockmaker Konstantin Chaykin.
Orthodox computus clocks
A mechanical Orthodox computus was developed by Konstantin Chaykin using a novel computus algorithm, that differs from Carl Friedrich Gauss's algorithm. The computus mechanism mechanically calculates the Orthodox Easter date at midnight at New Year and sets the calendar for the following year by means of three cam wheels, springs, levers, racks and three differential gears. In total, the computus mechanism consists of more than 300 parts. The Orthodox computus has been used in a series of Chaykin's astronomical desk clocks – the “Resurrection Computus Clock” (2007), the “Northern Computus Clock” (2015) and the supercomplicated “Moscow Computus Clock” (2016).
Computus clock/watch with a program cam wheel mechanism
This type of computus mechanism does not provide a mechanical calculation of the Easter date, but shows it by means of a program cam wheel, since the complicated design of a counting computus makes it difficult to integrate into the compact movement of a pocket watch and, in particular, a wristwatch. The only known example of a pocket watch with an indication of the Easter date according to the Gregorian calendar is the supercomplication “Calibre 89” pocket watch by the Swiss company Patek Philippe. Four copies of the “Calibre 89” and one functioning prototype were made in 1989 (the prototype is stored in the Patek Philippe Museum in Geneva, Switzerland). The Easter date display uses a program cam wheel valid for 28 years. It is assumed that this will be replaced as each term for its correct operation expires.
An extended program cam wheel mechanism was used in the display of the Easter date in the monumental astronomical clock of Beauvais Cathedral (France), built by the French clockmaker Auguste-Lucien Vérité from 1865 to 1868. The cam wheel is calculated for a period of 300 years, and the computus also has dials for indications of the dominical letter, the epact, the 28-year solar cycle, the golden number and the indiction.
A separated computus module
Separated computus module is produced to demonstrate the principal action of a computus device of a clock, to try and check the complicated mechanism. Separated modules are quite remarkable because just a few examples have ever been produced. The world's first computus module, realizing the Gregorian computus algorithm, was invented, designed and made by the French clockmaker Jean-Baptiste Schwilgué (“Comput ecclésiastique”, 1821, which was stolen from Strasbourg Cathedral in 1944, with the present location unknown). Subsequently, separated computus modules were made by the Danish clockmaker Jens Olsen (also called “Comput ecclésiastique”; 1924), and by the French watchmaker Frédéric Klinghammer, who reproduced Schwilgué's “Comput ecclésiastique” in a reduced scale (“Comput de Klinghammer”; 1977). The Russian watchmaker Konstantin Chaykin made an Orthodox computus module (“Comput Orthodoxe”) in 2007 to demonstrate the principal action of the mechanical Orthodox computus he had invented.
References
External links
Easter date algorithms by Henk Reints
Watches
Clocks
Calendars
Date of Easter | Computus clock | [
"Physics",
"Technology",
"Engineering"
] | 3,238 | [
"Machines",
"Calendars",
"Physical quantities",
"Time",
"Clocks",
"Measuring instruments",
"Physical systems",
"Spacetime"
] |
63,967,034 | https://en.wikipedia.org/wiki/Nuclear%20groove | A nuclear groove is an invagination of the nuclear envelope, in the longitudinal axis. It can be present in:
Thyroid neoplasms: It is a characteristic feature of papillary thyroid carcinoma, but has also been seen in other types of thyroid neoplasms, as well as in non-neoplastic thyroid lesions.
Ovarian tumors including Brenner tumors, adult granulosa cell tumors, and transitional cell tumors.
Breast carcinomas
Vaginal, cervical and/or endometrial neoplasms
Papillary neoplasms of several organs: papillary transitional cell carcinoma of the urinary bladder, papillary renal cell carcinoma, papillary endometrioid carcinoma of the prostate, in thymic carcinomas, and in non-epithelial tumors.
References
Histopathology | Nuclear groove | [
"Chemistry"
] | 185 | [
"Histopathology",
"Microscopy"
] |
63,967,046 | https://en.wikipedia.org/wiki/Chemistry%20Federation | The Chemistry Federation (, Fédéchimie) is a trade union representing workers in chemical and related industries in France.
The union was established on 24 January 1948, as the National Federation of the Chemical and Glass Industries. Its members had formerly belonged to the National Federation of Chemical Industries or the Glass Federation, both affiliated to the General Confederation of Labour, but objected to the influence of the French Communist Party in those unions. The new union affiliated to Workers' Force (FO).
In 1971, the union's general secretary, Maurice Labi, argued unsuccessfully for the union to merge with the Federation of Chemical Industries, an affiliate of the French Democratic Confederation of Labour. Defeated, Labi resigned and joined the CFDT with a few hundred supporters.
By 2002, the union claimed 15,000 members. In 2011, FO Textiles was dissolved, and the majority of its members transferred to the Chemistry Federation.
External links
References
Chemical industry in France
Chemical industry trade unions
Trade unions established in 1948
Trade unions in France | Chemistry Federation | [
"Chemistry"
] | 205 | [
"Chemical industry trade unions"
] |
63,967,359 | https://en.wikipedia.org/wiki/Peninsular%20Malaysian%20rain%20forests | The Peninsular Malaysian rain forests is an ecoregion on the Malay Peninsula and adjacent islands. It is in the tropical and subtropical moist broadleaf forests biome.
Geography
The ecoregion covers most of the southern Malay Peninsula in Malaysia and southern Thailand, and extends southwards to Singapore, the Riau Archipelago, and Lingga Islands, and east to the Anamba Islands.
The peninsula is fringed with mangroves, including the Indochina mangroves on the eastern shore, and the Myanmar coast mangroves on the western shore. The ecologically distinct Peninsular Malaysian peat swamp forests ecoregion are found in waterlogged lowlands on the east and west sides of the peninsula. The Titiwangsa Mountains form the mountainous backbone of the peninsula, and the range's higher elevations are home to the Peninsular Malaysian montane rain forests ecoregion.
Flora
The predominant trees are Cinnamomum cassia, Durio zibethinus, Garcinia mangostana, Artocarpus heterophyllus, Ficus benghalensis, Gnetum gnemon, Mangifera indica, Toona ciliata, Toona sinensis, Cocos nucifera, Tetrameles nudiflora, Ginkgo biloba, Shorea robusta, Prunus serrulata, Camphora officinarum, Tsuga dumosa, Ulmus lanceifolia, Tectona grandis, Terminalia elliptica, Terminalia bellirica, Quercus acutissima, and dipterocarps, including species of Anisoptera, Dipterocarpus, Dryobalanops, Hopea, and Shorea. The forests are home to over 15,000 tree species, and trees of the families Burseraceae and Sapotaceae are also common. Trees form a canopy 24-36 meters high, with emergent trees rising up 45 meters or more. The tallest emergent is Koompassia excelsa, known as tualang, which can grow more than 76 meters high.
Fauna
The ecoregion home to 195 mammal species, including several large and endangered species – Asian elephant (Elephas maximus), gaur (Bos gaurus), tiger (Panthera tigris), Malayan tapir (Tapirus indicus), and clouded leopard (Neofelis nebulosa). The Sumatran rhinoceros (Dicerorhinus sumatrensis) once inhabited the forests, but Malaysia's last rhinoceroses died in 2019, and the species' few remaining members survive only in Sumatra.
Conservation
A 2017 assessment found that 20,113 km2, or 16%, of the ecoregion is in protected areas. Protected areas in the ecoregion include Endau Rompin National Park (1191.59 km²), Endau-Kota Tinggi (West) Wildlife Reserve (805.49 km²), Endau-Kota Tinggi (East) Wildlife Reserve (106.5 km²), Krau Wildlife Reserve (623.96 km²), Mersin Wildlife Reserve (74.13 km²), and Ulu Muda Wildlife Reserve (1152.57 km²). Taman Negara National Park (4524.54 km²) and Royal Belum State Park (2072.0 km²) include portions of the ecoregion along with portions of the Peninsular Malaysian montane rain forests.
References
External links
Biota of Singapore
Ecoregions of Asia
Ecoregions of Indonesia
Ecoregions of Malaysia
Ecoregions of Malesia
Ecoregions of Thailand
Environment of Singapore
Flora of Malaya
Indomalayan ecoregions
Tropical and subtropical moist broadleaf forests | Peninsular Malaysian rain forests | [
"Biology"
] | 750 | [
"Biota by country",
"Biota of Singapore"
] |
75,433,719 | https://en.wikipedia.org/wiki/Dronabinol/acetazolamide | Dronabinol/acetazolamide (investigational name IHL-42X) is a combination therapy under investigation for sleep apnea. It is developed by Incannex Healthcare.
References
Combination drugs | Dronabinol/acetazolamide | [
"Chemistry"
] | 45 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
75,433,738 | https://en.wikipedia.org/wiki/Mufemilast | Mufemilast (Hemay005) is a small-molecule inhibitor of phosphodiesterase 4. It is developed by Hemay Pharmaceutical for psoriasis.
References
PDE4 inhibitors
Imides
Thiophenes
Acetamides
Sulfones
Small-molecule drugs
Ethoxy compounds
Methoxy compounds
Phenol ethers | Mufemilast | [
"Chemistry"
] | 74 | [
"Imides",
"Sulfones",
"Functional groups"
] |
75,434,340 | https://en.wikipedia.org/wiki/Protein%20therapeutics | Protein therapeutics are proteins used as experimental or approved therapies for disease states. They include "monoclonal antibodies (mAbs), peptide hormones, growth factors, plasma proteins, enzymes, and hemolytic factors" While proteins can be more specific and flexible in their mechanism of action compared to small-molecule drugs, duration of action and drug delivery can be a challenge.
References
Further reading
Proteins | Protein therapeutics | [
"Chemistry"
] | 83 | [
"Biomolecules by chemical classification",
"Pharmacology",
"Medicinal chemistry stubs",
"Molecular biology",
"Proteins",
"Pharmacology stubs"
] |
75,436,957 | https://en.wikipedia.org/wiki/NGC%20665 | NGC 665 is a Lenticular galaxy 236 million light-years away in the constellation Pisces. NGC 665 was discovered in 1786 by William Herschel, and is 100,000 light-years across. In the center of NGC 665, a small halo of dust and gas can be seen, indicating some small star-forming regions. NGC 665 is not known to have an active galactic nuclei, as seen in the SDSS image.
Nearby and satellite galaxies
Like other galaxies, NGC 665 has a satellite galaxy (MCG 02-05-022), a dwarf elliptical galaxy, as seen in the SDSS image of NGC 665. Its nearby cluster of stars is NGC 663.
According to A.M. Garcia, NGC 665 is a member of the NGC 673 Group (also known as LGG 31). This group contains at least 17 galaxies, including IC 156, IC 162, NGC 673, NGC 677, NGC 683, and 11 galaxies from the UGC catalogue.
References
External links
Lenticular galaxies
Pisces (constellation)
0665
6415
1223
+02-05-019 | NGC 665 | [
"Astronomy"
] | 236 | [
"Pisces (constellation)",
"Constellations"
] |
75,438,151 | https://en.wikipedia.org/wiki/HD%20110067 | HD 110067 is a star with six known sub-Neptune exoplanets (b, c, d, e, f, g) with radii ranging from 1.94 to 2.85 . The planets orbit the host star in a rhythmic orbital resonance. The star, and related planetary system, is located 105 light-years away in the constellation Coma Berenices.
HD 110067 is part of a wide triple star system, along with the spectroscopic binary system HD 110106.
Description
HD 110067, located 105 light-years away in the constellation Coma Berenices, is orbited by six known sub-Neptune exoplanets (b, c, d, e, f, g) with radii ranging from 1.94 to 2.85 , and with densities (and solid cores) similar to that of gas giants in the Solar System. None of the planets in the planetary system were found to be in the habitable zone for life as we know it.
Discovery
The two innermost exoplanets orbiting HD 110067, a bright K0-type star, were first detected by the TESS (NASA) space telescope, using the transit method, in 2020. The remaining four exoplanets were later confirmed in 2023 as a result of additional observations using the CHEOPS (European Space Agency) space telescope.
Scientific importance
On 29 November 2023, an international team of astronomers, led by Rafael Luque, astronomer from the University of Chicago, published a review of the discovery in the journal Nature entitled, "A resonant sextuplet of sub-Neptunes transiting the bright star HD 110067". According to Luque, "It’s like looking at a fossil: The orbits of the planets today are the same as they were a billion years ago."
Further study of the HD 110067 planetary system may provide a better understanding of how the pattern of the planetary orbits in the Solar System arose, which once may have begun harmoniously, but later turned chaotic. The result, possibly, of a passing star or planet or some other astronomical object capable of disrupting the nascent harmonic orbital dynamics. Additionally, further studies of the system, including compositional studies of the planetary interiors and atmospheres, may also provide a better understanding of the conditions that potentially may support life.
Planetary system
Six known sub-Neptune exoplanets (b, c, d, e, f, g) with planetary radii ranging from 1.94 to 2.85 from HD 110067, the host star. All planets are smaller than Neptune and have large atmospheres. The star and related planetary system are located 105 light years away, in the constellation Coma Berenices. Masses of all six of the planets in the system range from 3.9 (mass of Earth) to 8.5 . All of the planetary orbits in the HD 110067 system are closer to their star than distance between the planet Mercury and the Sun.
The planets orbit the host star in synchronized rhythms of orbital resonance (a rare 1 percent of such systems in the Milky Way galaxy have this symmetry): the innermost planet orbits three times for every two times for the next planet out – a so-called 3:2 resonance; this same 3:2 resonance also applies to the second and third planet, as well as to the third and fourth planet; whereas the fourth planet orbits four times for every three times for the fifth planet out – in a so-called 4:3 resonance; additionally, the penultimate fifth planet orbits the sixth planet out in this same 4:3 resonance. Further, the innermost planet completes six orbits in exactly the same time the outermost planet completes one orbit.
The resonance ratio for the entire system is 54:36:24:16:12:9. The resonance period is ~492 (Earth-days).
See also
HD 10180 – star with six known planets
Kepler-11 – star with six Neptune-like planets
LHS 1140 – star with a system of planets having an atmosphere
List of potentially habitable exoplanets
LP 890-9 – second known coolest star with planets
Tabby's Star – star with notable transit data
TRAPPIST-1 – star with a resonant chain of Earth-sized planets
References
Further reading
External links
2023 in outer space
Coma Berenices
BD+20 2748
110067
K-type main-sequence stars
Planetary systems with six confirmed planets
1835
347332255
Triple star systems | HD 110067 | [
"Astronomy"
] | 933 | [
"Coma Berenices",
"Constellations"
] |
75,438,211 | https://en.wikipedia.org/wiki/Stellar%20influences%20on%20an%20origin%20of%20life%20setting | The origin of life is an ongoing field of research that requires the study of interactions of many physical and biological processes. One of these physical processes has to do with the characteristics of the host star of a planet, and how stellar influences on an origin of life setting can dictate how life evolves, if at all. Life required an energy source at its origin, and scientists have long speculated that this energy source could have been the ultraviolet radiation that rains down on Earth. Though it may potentially be harmful to life, UV has also been shown to trigger important prebiotic reactions that might have taken place on a younger Earth.
Main sequence M dwarf stars are generally the focus of studies that investigate the role of UV in prebiotic chemistry and an origin of life setting, given that the potential habitability of planets in these systems is a big field of research, and the lifecycles and characteristics of these stars are relatively well known. Furthermore, in the context of biosignatures, M dwarfs are considered one of the better places to look to find life for various reasons (see: habitability of M dwarfs). In order to experimentally investigate the effects of UV on the origin of life, studies make use of UV sources such as mercury lamps, and computational simulations of radiative transfer that model how UV interacts with different atmospheric compositions with different levels of shielding. Altogether, these methods allow scientists to test how different aspects of prebiotic chemistry operate under conditions of UV (so called 'light chemistry') versus how they operate in conditions with reduced UV or none at all ('dark chemistry').
This work is helpful for understanding the conditions under which life might have started on a prebiotic Earth and can also be used to identify exoplanets that may have the right conditions for life. Since the first discovery in 1992, more than 5000 exoplanets have been found, and a subset of these exist within the liquid water habitable zone of their host star. By experimentally estimating how much light is needed for UV photochemistry based on reaction rates for light chemistry versus dark chemistry, scientists have designated another zone around a star, called the 'abiogenesis zone'. This is based on an understanding of how proximity to a host star changes the flux of UV, and how that influences prebiotic chemistry. A planet existing within overlap of the habitable zone with the abiogenesis zone of a given star would theoretically provide the right conditions for life to evolve there.
UV and abiogenesis
UV light is considered a key component of prebiotic chemistry on an early Earth. Because of their short wavelengths (10-400 nanometers), UV photons carry enough energy to effect the electronic structure of molecules by interacting with molecular bonds by breaking them (photolysis), ionizing them (photoionization), or exciting their electrons (photoexcitation). This can sometimes lead to degradation of biologically important molecules, causing subsequent environmental stress and providing a barrier to abiogenesis. In 1973, Carl Sagan first suggested that UV might pose a selection threat against abiogenesis because early biological repair mechanisms would have been more primitive than now, and early prebiotic chemistry would have faced intense selection pressure to shield against UV.
Conversely, these potentially destructive properties are also what makes UV an ideal candidate for a source of energy, similar to the Miller-Urey experiment that synthesized prebiotic molecules using simulated lightning. Across many different studies of prebiotic chemistry, UV light has been incorporated to explain the origin of chirality, the synthesis of amino acids, and the formation of ribonucleotides. Due to a lack of biogenic UV-shielding O2 and O3 present in the prebiotic atmosphere, and the fact that a younger Sun at the time had a higher fractional output of UV (see: the young sun paradox), UV is expected to have been common in the prebiotic environment. One study suggested that in the absence of O3, UV light with at wavelengths < 300 nm contributed 3 orders of magnitude more energy than electrical discharge to the surface of an early Earth.
Experimental methods
Given that UV may have been the most available source of energy for prebiotic chemistry, many experiments aim to deduce and quantify the effects of UV irradiance on synthesis pathways. A fraction of these studies deal with the formation of prebiotic molecules on interstellar ices and cometary surfaces. For this, UV is sourced from lamps or synchrotrons in ultrahigh vacuum conditions, and the UV output is generally below a wavelength of 160 nm. Other studies are interested in prebiotic chemistry that occurred in aqueous solution, and also make use of UV lamps. UV lamps are a good source because they are safe, stable, and affordable. However their output is generally narrowband, and real solar UV output is broadband.
Many UV-dependent prebiotic reactions are wavelength dependent, so research using the narrowband UV lamps may not reach the same conclusions as those conducted under more realistic conditions. There are many studies that include UV as a key component of their prebiotic synthesis pathways. In particular, a ribonucleotide synthesis and a sugar synthesis pathway both rely on irradiation from a mercury UV lamp. For all studies, and the se two in particular, early Solar UV irradiation and variability would have heavily influenced the availability of prebiotically important feedstock gases like CH4 and HCN (hydrogen cyanide). And although the effects are difficult to constrain due to lack of a full understanding of what the prebiotic Earth environment looked like, understanding how prebiotic chemistry might have proceeded in the presence of solar UV is one step towards a better understanding of abiogenesis.
Ribonucleotide synthesis
A key issue facing the RNA world hypothesis, and the eventual pathway to abiogenesis, is how the comparatively complex RNA molecules actually came to be. One proposed pathway to RNA synthesis under plausible prebiotic conditions used irradiation from UV light at 254 nm. The UV here plays two roles: first, it destroys competing molecules that are generated along the synthesis pathway, and secondly, it was required to promote the synthesis via photoactivation.
Simple sugar synthesis
A proposed companion synthesis reaction of two- and three-carbon sugars glycolaldehyde and glyceraldehyde from hydrogen cyanide (HCN) and formaldehyde also requires UV irradiation. Previously, the mechanism used to explain the prebiotic synthesis of sugars was the formose reaction, wherein formaldehyde polymerizes to form longer sugars. This polymerization tends to run away, and leads to an insoluble tar, effectively terminating the reaction. The UV-driven synthesis, however, is much more selective and generates a smaller number of products that are useful for further chemical reactions. This synthesis relies of production of solvated electrons and protons via photoionization of a photocatalytic transition metal complex under UV light at 254 nm.
Stellar influence
Further considerations of environments conducive to prebiotic chemistry extend beyond how the Sun influenced Earth, and are interested in how other stars and their different characteristics might affect abiogenesis on other planets as well. Stars are not stagnant; from when they first start fusing hydrogen on the main sequence, to when they reach the end stages of their lifetimes, they are outputting energy in the form of radiation and high energy particles. Radiation can be, for example, x-ray coronal emissions or flares. The high energy particles emitted come in the forms of winds, and coronal mass ejections (CMEs). As stars evolve, so do their emissions; younger stars tend to be the most active, meaning they have stronger winds, larger flaring events, and an increased frequency of CMEs. This means that planets orbiting younger stars would endure more volatile stellar events that impact their habitable and abiogenesis zones, perhaps even making them transient.
M dwarf stars range in temperature from 2,000 to 3,500 K, and they exhibit variable activity over both short and long timescales. For example, in one study of 177 M dwarfs of varying spectral times, 75% of them exhibited long-term variability. Stellar activity is linked to rotation, so the fraction of active stars tends to be much higher amongst M dwarfs compared to solar-type stars (G type). This is because they tend to have longer rotational braking times (timescale for stellar rotation to slow), and show stronger activity based on their period of rotation. Deducing the right balance of stellar activity required to help prebiotic chemistry along without completely sterilizing the surface of a planet is complicated. It depends on multiple stellar and planetary factors, such as frequency of stellar events, intensity of stellar events, planetary atmosphere composition (radiation shielding effects), and the existence and strength of a planetary magnetic field (can provide further shielding).
M dwarf UV shortage
Although M dwarfs exhibit high variability, because of their low luminosities they emit less prebiotically relevant near-UV (NUV) radiation, which can lead to a shortage thereof. Additionally, planetary atmospheres of specific compositions can further increase this shortage by functioning as UV shields due to the absorption features of their constituent molecules. This acts to reduce the amount of stellar UV reaching the surface, and can act as a barrier to UV-driven prebiotic chemistry. For example, planets orbiting M dwarfs with inefficient atmospheric sinks of O2 and CO, combined with a CO2 rich atmosphere are more likely to built up UV shields such as O3 that can block the already low NUV flux reaching the surface from the star.
Potential solutions
Effects like this can be theoretically overcome in a number of ways, both to do with characteristics of the star and the planet in question. Firstly, this issue could be overcome simply by having a thinner atmosphere that blocks less of the impinging UV. This kind of situation could arise in the case where elevated UV emission from the M dwarf strips the atmosphere of habitable zone planets orbiting close enough in. Relative dose rates of UV to the surface would then increase. However, it is likely that the increased UV only served to promote destructive reactions such as photolysis of a prebiotically relevant RNA monomer. This is because the thinner atmosphere was admitting destructive far-UV (FUV) wavelengths and making the environment inclement to abiogenesis. Thus, atmospheric stripping is not deemed an effective way to solve the M dwarf UV shortage problem.
Alternatively, researchers considered whether M dwarf flaring might play a role in providing the requisite UV for abiogenesis. Typically, these kinds of flaring events are deemed fatal for life, because of the increase in output of NUV. Given that flaring is cyclical, there exists a possible scenario whereby photosensitive prebiotic chemistry is promoted during the flares, and ceases in the intervening periods. This kind of situation is analogous to terrestrial day/night cycles, and is proposed as the best mechanism to solve the shortage problem around particularly active M dwarfs. That being said, further work is needed in order to constrain whether shorter duration/higher intensity UV flux from a flare is even sufficient to promote prebiotic chemistry. Additionally, intense flaring events run the risk of completely ablating a planetary atmosphere, which would sterilize the surface, and effectively counteract this proposed solution.
Alternative stellar classes
Main sequence M dwarfs are not the only stellar host considered in studies of UV prebiotic chemistry. Younger M dwarfs, such as the pre-main sequence ones emit more of their bolometric luminosity in the NUV range. Depending on how low their mass is, some of these stars remain in this state for up to 1 Gyr (billion year). From here, it is possible to begin assessing whether planets orbiting a star in these conditions might receive NUV insolation that is actually comparable to solar-like stars (G type). That being said, earlier type M dwarf stars have higher bolometric luminosity, which increases the likelihood of their orbiting habitable zone planets undergoing a runaway greenhouse state if they are orbiting closer in. Temperatures under these conditions would reach > 1000 K and easily vaporize any water on the surface. Consequently, aqueous-phase (in water) prebiotic chemistry is unlikely to proceed which is a definite barrier to aqueous prebiotic chemistry.
For planets further from the star in the habitable zone during this pre-main sequence phase, they may achieve habitable conditions and even abiogenesis for up to Gyr timescales. The caveat to this is that once their host star exits the pre-main sequence phase, the total bolometric luminosity will decrease, and the planets will no longer exist within the habitable zone. Unless clement temperatures are maintained by some intrinsic planetary mechanism such as greenhouse warming liquid water will freeze, and if life is not immediately killed off it would be confined to volcanic or subsurface reservoirs. All the cons aside, planets in the habitable zones of these late-type, low mass pre-main sequence M dwarfs are still an area of focus for researchers interested in UV-driven prebiotic chemistry.
K-type
Going beyond M dwarf stars, main sequence K dwarf stars are also considered as possible hosts of habitable and abiogenetic planets. Based on a chemical pathway for photochemically building up prebiotic reservoirs, it is possible that hotter stars, such as spectral type K are better at powering prebiotic chemistry. A main sequence K star (spectral class: K5), has a temperature of around 4400 K. For stars cooler than this, and in the absence of cyclical stellar activity, the incident flux is too low for the planets that exist within the habitable zone to also exist within the abiogenesis zone. This consequently sets a potential boundary on what kinds of stars are most likely to have sufficient overlap in their habitable and abiogenesis zones.
Prebiotic Earth UV conditions
Just as understanding the UV flux of different stars can somewhat constrain favorable conditions for abiogenesis, so does understanding what the UV environment would have looked like on a prebiotic Earth. Given certain atmospheric compositions, UV surface fluence is generally a function of albedo, and solar zenith angle (SZA). In experimental situations where atmospheric composition is left as a free variable, it also heavily dictates not only the bolometric surface flux of UV, but also what particular wavelengths are transmitted that may or may not be harmful to prebiotic chemistry and abiogenesis. This presents the need for experiments to reduce the uncertainty still surrounding the planetary conditions and the surface UV at abiogenesis.
For consideration of the surficial UV conditions of a prebiotic Earth, there are 7 atmospheric gases that can influence UV attenuation and hence prebiotic chemistry: CO2, SO2, H2S, CH4, H2O, O2, and O3. For each of these gases, different constraints provide different estimates for their effect on UV transmission. Depending on the amount of transmission, different biologically effective doses (BEDs) of UV will be delivered to the surface; too little prohibits prebiotic chemistry, and too much is harmful. Additionally, solar UV input shapes the overall photochemistry of Earth's atmosphere which impacts the availability of chemical reactants.
Carbon dioxide (CO2)
One study showed that high levels of atmospheric CO2 can suppress UV-relevant prebiotic chemistry, due to the argument that atmospheric CO2 would cut off UV fluence for wavelengths shorter than 204 nm. This reduces the surface flux of photons at energies useful for prebiotic chemistry. At lower levels of atmospheric CO2 however, the transmitted UV can moderately enhance prebiotic chemistry. This study found the overall effects of CO2 on the BED of UV to be minimal, in the absence of other absorbers. For the range of CO2 values evaluated, the variation of the biologically effective dose of radiation was <2 orders of magnitude.
However, given the significant presence of other absorbers (below) that have absorption cross sections from 100-500 nm, they could have influenced the surface UV environment of an early Earth.
Sulfur dioxide (SO2)
SO2 strongly absorbs over a much wider range than CO2, but is conversely more vulnerable to loss via photolysis and oxidation reactions. Volcanos are a significant source of SO2, and assuming levels of volcanic outgassing at abiogenesis (around 3.9 Ga) were comparable to today, the build-up of SO2 would not significantly influence the surface UV environment. However, during transiently high levels of volcanic outgassing SO2 would build-up, and under these conditions could have heavily modified surface UV irradiance. Higher levels of SO2 reduce BEDs by over 60 orders of magnitude, which implies that UV-driven prebiotic chemistry might not have been sustained.
Hydrogen sulfide (H2S)
Like SO2, H2S is a strong and broad absorber of UV, and is primarily generated through volcanic outgassing. As a result of its vulnerability to atmospheric loss through photolysis and oxidation reactions, it is not expected that H2S would have been a significant constituent of a prebiotic environment, let alone that it might have had an impact on prebiotic chemistry. As with SO2, higher levels of H2S as a result of a transient increase in volcanic activity, may have affected the surface UV irradiation. The lower expected BEDs might have reduced the ability of some prebiotic chemical pathways to proceed.
Methane (CH4)
In the presence of trace amounts of CO2, UV absorption by CH4 is considered negligible. This is because CH4 absorbs UV below 165 nm. As a result, CH4 is not very useful for constraining surface UV in the presence of CO2.
Water (H2O)
Primordial atmospheric water content is hard to constrain, but it is a strong UV absorber for wavelengths below 198 nm. For plausible levels of H2O, UV flux is blocked below around 201 nm even without attenuation from CO2. This means that regardless of the level of CO2 present at a given time, UV more energetic than around 200 nm would have probably been unavailable for prebiotic chemistry.
Molecular oxygen (O2)
O2 is a strong shield for UV, but at levels expected from photochemical models, O2 does not provide strong constraints on the surface UV environment. However, given that O2 is a stronger absorber than CO2, it is possible that O2 might have an effect in situations where CO2 is a smaller constituent in the atmosphere. At such high levels, O2 may start to have a noticeable effect on UV transmission, but at abiogenesis it is unlikely that high levels were achieved given a strong reducing sink from volcanogenic gases, and a lack of a strong source.
Ozone (O3)
Ozone is a well known greenhouse gas that acts as a shield for UV. It is generated in the atmosphere via photolysis of O2, hence its abundance is linked to that of O2. At nominal O2 values expected for around abiogenesis, O3 is not expected to have a huge influence on the surface UV.
Considerations for biosignatures
Prebiotic chemistry is heavily linked to UV irradiation from the host star of the planet. In particular, frequency flaring from M dwarf stars might be enough to drive prebiotic photochemistry on terrestrial planets within their habitable zone. This does require that the atmosphere can survive the flaring and not be fully ablated thus sterilizing the surface. But under those conditions, flaring rates for stars, and particularly M dwarfs early in their evolution is relevant to biosignature detection.
Detecting a biosignature requires finding a planet where life has existed long enough to noticeably change the planet in detectable ways either through its surface or atmosphere (see: biosphere). Given that UV impacts prebiotic chemistry, understanding stellar UV variations is an important step on the way to finding potential candidates for biosignature searches, as well as understanding more about abiogenesis on Earth.
References
Origin of life
Astrobiology | Stellar influences on an origin of life setting | [
"Astronomy",
"Biology"
] | 4,128 | [
"Origin of life",
"Speculative evolution",
"Astrobiology",
"Biological hypotheses",
"Astronomical sub-disciplines"
] |
75,438,680 | https://en.wikipedia.org/wiki/Lithium%20permanganate | Lithium permanganate is an inorganic compound with the chemical formula LiMnO4. It can be produced by the reaction of lithium sulfate and barium permanganate, and the trihydrate LiMnO4·3H2O can be crystallized from the solution. It decomposes violently at 199 °C:
However, later research found that the thermal decomposition products of lithium permanganate are more complex, with products such as Li2MnO3 and LiMn2O4 being generated.
References
Lithium compounds
Permanganates | Lithium permanganate | [
"Chemistry"
] | 113 | [
"Salts",
"Lithium salts",
"Oxidizing agents",
"Permanganates"
] |
75,438,735 | https://en.wikipedia.org/wiki/Cadmium%20permanganate | Cadmium permanganate is an inorganic compound with the chemical formula Cd(MnO4)2. It can form the hexahydrate Cd(MnO4)2·6H2O.
Preparation
Cadmium permanganate can be obtained by reacting cadmium sulfate and barium permanganate. After removing the barium sulfate precipitate, the solution is crystallized in the dark:
Cadmium permanganate can also be produced by reacting manganese heptoxide with cadmium oxide or cadmium hydroxide.
Properties
Cadmium permanganate hexahydrate loses water of crystallisation at 61~62 °C, and anhydrate can be obtained at a constant temperature of 90 °C. The anhydrous form begins to decompose at 108 °C:
References
Cadmium compounds
Permanganates | Cadmium permanganate | [
"Chemistry"
] | 179 | [
"Oxidizing agents",
"Permanganates"
] |
75,439,206 | https://en.wikipedia.org/wiki/Sirius%20%28mythology%29 | In Greek and Roman mythology and religion, Sirius (, ; ) is the god and personification of the star Sirius, also known as the Dog Star, the brightest star in the night sky and the most prominent star in the constellation of Canis Major (or the Greater Dog). In ancient Greek and Roman texts, Sirius is portrayed as the scorching bringer of the summer heatwaves, the bright star who intensifies the Sun's own heat.
Etymology
The ancient Greek word and proper noun has been connected to the verb (seíō), meaning to 'sparkle, to gleam' and has thus an Indo-European etymology; Furnée on the other hand compared it to the word (tírios), the Cretan word for summer, which, if correct, would mean that the word is pre-Greek instead. From this name an ancient phrase was derived, (literally "sirian passion", meaning burning passion).
Description
Sirius's divine parentage is not made entirely clear in ancient texts; in the Theogony the poet Hesiod names Eos (the dawn goddess) and her husband Astraeus (a star god) as the parents of all stars, although this usually referred to the 'wandering stars', that is the five planets.
Sirius is first mentioned by name in Hesiod's Works and Days, although he is also strongly alluded to in Homer's Iliad, with his brilliance used as a metaphor for the shiny bronze armors of the soldiers, and in another point he is presented as an ominous death star foreshadowing the fate of the doomed Hector in his fight against Achilles. Apollonius of Rhodes calls him "brilliant and beautiful but full of menace for the flocks," and both Aratus and Quintus of Smyrna speak of his rise in conjunction to that of the Sun (the god Helios). The Roman poet Statius says:
In addition to that, "Sirius" was sometimes used as an epithet of Helios himself due to the Sun's great heat and warmth.
Sirius and his appearance in the sky in July and August was associated with heat, fire and fever by the ancient Greeks from early on, as was his association with dogs; as the chief star in the constellation Canis Major, he was referred to as 'the Dog', which also referred to the entire constellation. The arrival of Sirius in the sky was seen as the cause behind the hot, dry days of summer; dogs were thought to be the most affected by Sirius's heat, causing them rapid panting and aggressive behaviour towards humans, who were in danger of contacting rabies from their bites.
Sirius, a luminous star brighter than the Sun, is very often described as red in some ancient Greek and Roman texts, put in the same category as the red-shining Mars and Antares, although in reality it is a white-blue star.
Mythology
Romance with Opora
In a lesser known narrative, back when the stars walked the earth, Sirius was sent on a mission on land. There he met and fell madly in love with Opora, the goddess of fruit as well as the transition between summer and autumn. He was however unable to be with her, so in anger he began to burn even hotter. The mortals started to suffer due to the immense heat, and pleaded to the gods. Then the god of the north wind, Boreas, ordered his sons to bring Opora to Sirius, while he himself cooled off the earth with blasts of cold, freezing wind. Sirius then went on to glow and burn hot every summer thereafter during harvest time in commemoration of this event and his great love, explaining the heat of the so-called dog days of summer, which was attributed to this star in antiquity.
The story is generally believed to have originated from a lost play entitled Opora, by the Athenian playwright of Middle Comedy Amphis, and a work of the same name by Amphis's contemporary Alexis. It also parallels the tale of young Phaethon, the son of the sun-god Helios who drove his father's sun chariot for a day and ended up burning the earth with it, prompting the entire nature to beg Zeus for salvation. In Euripides's version of the story, Helios accompanies Phaethon in his journey riding on a steed named Sirius.
Orion
After the mortal hunter Orion was killed by the scorpion the earth-goddess Gaia sent to punish him, he was transported by the gods (usually either Artemis or Zeus) in the stars as the homonymous constellation, where he was ever accompanied by his faithful dog, who was represented by Sirius (and Canis Major) in their new celestial lives. This belief seems to originate from the fact that the Dog forms a sky-picture with Orion, as the two hunt Lepus (the Hare) or the Teumessian fox through the sky.
Maera
Sirius is also identified with Maera (), which was another name for the dog star in antiquity. In mythology Maera was the hound of Icarius, an old Athenian an who was taught the art of wine-making by Dionysus. When Icarius shared the wine with the other Athenians he was accused of poisoning them (due to the wine's intoxicating properties which made them pass out) and he was thus killed in vengeance; his daughter Erigone, after being led to his corpse by Maera, took her own life by hanging. Dionysus then transferred all three in the sky, with Maera becoming the star Canicula, which was the Romans' name for Sirius, although Hyginus himself claimed that the Greeks used Procyon for Canicula.
Other works
In second-century author Lucian's satire work A True Story, the people of Sirius, here presented as an inhabited world, send an army of Cynobalani (dog-faced men mounting gigantic winged acorns) to assist the Sun citizens in their war against the inhabitants of the Moon. Sirius, associated with heat, is an appropriate ally for the kingdom of the Sun.
Cult
Not much evidence on Sirius' ancient cult is preserved. In antiquity, Sirius might have been venerated on the island of Kea with summer sacrifices to his honour during the Hellenistic period, though certain doubts have been cast on whether such cult did exist indeed; at any point, that cult surely did not predate the third century BC. Keans would observe Sirius's rising from a hilltop; if the star rose clear and brilliant it was a good sign of health, but if it appeared faint or misty it was seen as ominous. Sirius was also represented on coinage from Kea.
Genealogy
See also
Orithyia of Athens
Hou Yi and the Ten Suns
Pyroeis, the star of Mars
References
Bibliography
Apollonius Rhodius, The Argonautica translated by E. V. Rieu, Penguin Classics, April 1959. .
Aratus Solensis, Phaenomena translated by G. R. Mair. Loeb Classical Library Volume 129. London: William Heinemann, 1921. Online version at the Topos Text Project.
Gaius Julius Hyginus, De Astronomica from The Myths of Hyginus translated and edited by Mary Grant. University of Kansas Publications in Humanistic Studies. Online version at the Topos Text Project.
Hesiod, Theogony, in The Homeric Hymns and Homerica with an English Translation by Hugh G. Evelyn-White, Cambridge, MA., Harvard University Press; London, William Heinemann Ltd. 1914. Online version at the Perseus Digital Library.
Hesiod, Works and Days, in The Homeric Hymns and Homerica with an English Translation by Hugh G. Evelyn-White, Cambridge, MA., Harvard University Press; London, William Heinemann Ltd. 1914. Online version at the Perseus Digital Library.
Homer, The Iliad with an English Translation by A.T. Murray, Ph.D. in two volumes. Cambridge, MA., Harvard University Press; London, William Heinemann, Ltd. 1924. Online version at perseus.tufts Library.
Online version at Perseus.tufts project.
Quintus Smyrnaeus, Quintus Smyrnaeus: The Fall of Troy, translated by Arthur S. Way, Cambridge, Massachusetts, Harvard University Press, 1913. Internet Archive.
Statius, Silvae, translated by John Henry Mozley, London, W. Heinemann, Ltd.; New York, G. P. Putnam's Sons, 1928. Available on Internet Archive.
External links
SIRIUS on the Theoi Project
Stellar gods
Greek gods
Personifications in Greek mythology
Summer deities
Children of Eos
Fire gods
Light gods
Dog gods
Kea (island)
Epithets of Helios
Astronomical myths
Canis Major | Sirius (mythology) | [
"Astronomy"
] | 1,830 | [
"Astronomical myths"
] |
75,439,302 | https://en.wikipedia.org/wiki/Power%20cone | In linear algebra, a power cone is a kind of a convex cone that is particularly important in modeling convex optimization problems. It is a generalization of the quadratic cone: the quadratic cone is defined using a quadratic equation (with the power 2), whereas a power cone can be defined using any power, not necessarily 2.
Definition
The n-dimensional power cone is parameterized by a real number . It is defined as:
An alternative definition is
Applications
The main application of the power cone is in constraints of convex optimization programs. There are many problems that can be described as minimizing a convex function over a power cone.
References
Convex optimization | Power cone | [
"Mathematics"
] | 133 | [
"Geometry",
"Geometry stubs"
] |
75,442,022 | https://en.wikipedia.org/wiki/Garfield%27s%20proof%20of%20the%20Pythagorean%20theorem | Garfield's proof of the Pythagorean theorem is an original proof the Pythagorean theorem discovered by James A. Garfield (November 19, 1831 – September 19, 1881), the 20th president of the United States. The proof appeared in print in the New-England Journal of Education (Vol. 3, No.14, April 1, 1876). At the time of the publication of the proof Garfield was not the President, he was only the Congressman from Ohio. He assumed the office of President on March 4, 1881, and served in that position only for a brief period up to September 19, 1881 when he was assassinated. Garfield was the only President of the United States to have contributed anything original to mathematics. The proof is nontrivial and, according to the historian of mathematics, William Dunham, "Garfield's is really a very clever proof." The proof appears as the 231st proof in The Pythagorean Proposition, a compendium of 370 different proofs of the Pythagorean theorem.
The proof
In the figure, is a right-angled triangle with right angle at . The side-lengths of the triangle are . Pythagorean theorem asserts that .
To prove the theorem, Garfield drew a line through perpendicular to and on this line chose a point such that . Then, from he dropped a perpendicular upon the extended line . From the figure, one can easily see that the triangles and are congruent. Since and are both perpendicular to , they are parallel and so the quadrilateral is a trapezoid. The theorem is proved by computing the area of this trapezoid in two different ways.
.
From these one gets
which on simplification yields
References
Articles containing proofs
Theorem
Euclidean plane geometry
History of geometry
Theorems in plane geometry
James A. Garfield | Garfield's proof of the Pythagorean theorem | [
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75,443,931 | https://en.wikipedia.org/wiki/Fauna%20of%20Guyana | The fauna of Guyana comprises all the animal species inhabiting the country of Guyana, which is part of the neotropical realm. Guyana has many endemic species and one of the highest biodiversity rates in the world as a result of the majority of the country being part of the Amazon rainforest, and as a result a large amount of the species being types of frogs or spiders. Guyana's has three distinct main biomes are tropical rainforests, wetlands, and savannas, and each biome has unique fauna associated.
There are 47,677 unique species classified as part of Guyana, of which 17,291 (36.27%) are classified as an endangered species. As part of conservation efforts, parts of Guyana have been designated as national parks.
Rainforest fauna
Being part of the Amazon rainforest, a lot of Guyana's rainforest fauna is not exclusively native. Its high biodiversity also means that a significant variety of creatures exist within the country.
Mammals
Guyana's rainforests have a wide variety of mammals, the most notable being the Jaguar as it is featured on the coat of arms. Most mammals in Guyana are shared with other countries via the Amazon rainforest. Examples of shared mammals include the three-toed sloth and the capuchin monkey, the latter of which has protection in the form of the Iwokrama Forest Reserve.
Reptiles and amphibians
Amphibians and reptiles make up another significant portion of the habitat. Snakes are a common reptile in the tall grass of the rainforest. As such, notable examples include the heaviest snake in the world, the green anaconda, the rainbow boa, and the bushmaster.
Birds
Guyana is additionally home to many species of birds. The national bird is the Hoatzin, found in the rainforest along the Berbice River. Other common native birds include the horned screamer and the great tinamou.
Conservation
The largest threats to conservation of species in Guyana is pollution and habitat destruction arising from increased industrialisation, and poaching. An additional threat is invasive species which disrupt the local ecosystem. To help with conservation, the Protected Areas Commission was formed, which designates certain parts of the country as national parks and protected areas, preventing development.
Articles by Region
References
Fauna of Guyana
wildlife by country | Fauna of Guyana | [
"Biology"
] | 457 | [
"Biota by country",
"Wildlife by country"
] |
75,444,149 | https://en.wikipedia.org/wiki/Apadamtase%20alfa | Apadamtase alfa, sold under the brand name Adzynma, is an enzyme replacement therapy used for the treatment of thrombotic thrombocytopenic purpura. Apadamtase alfa is a human recombinant a disintegrin and metalloproteinase with thrombospondin motifs 13. It is given by injection into a vein.
The most common side effects include headache, diarrhea, migraine, abdominal pain, nausea, upper respiratory tract infection, dizziness and vomiting. During the clinical studies, no adverse events, including allergic reactions, were observed during the administration of Adzynma.
Apadamtase alfa was approved for medical use in the United States in November 2023, and in the European Union in August 2024.
Medical uses
Apadamtase alfa is indicated for prophylactic (preventive) or on demand enzyme replacement therapy in people with congenital thrombotic thrombocytopenic purpura.
History
The efficacy of apadamtase alfa in the prophylactic treatment of participants with congenital thrombotic thrombocytopenic purpura was evaluated in 46 participants who were randomized to receive six months of treatment with either apadamtase alfa or plasma based therapies (Period 1), then crossed over to the other treatment for six months (Period 2). The efficacy was demonstrated based on the incidence of thrombotic thrombocytopenic purpura events, and thrombotic thrombocytopenic purpura manifestations, as well as the incidence of the need for supplemental doses.
The efficacy of on demand enzyme replacement therapy was evaluated based on the proportion of acute thrombotic thrombocytopenic purpura events responding to apadamtase alfa in both the prophylactic and the on-demand cohorts throughout the duration of the study. All acute and subacute thrombotic thrombocytopenic purpura events resolved after treatment with either apadamtase alfa or plasma based therapies.
The US Food and Drug Administration (FDA) granted the application for apadamtase alfa priority review, fast track, and orphan drug designations. The FDA granted approval of Adzynma to Takeda Pharmaceuticals U.S.A. Inc.
Society and culture
Legal status
In May 2024, the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) adopted a positive opinion, recommending the granting of a marketing authorization under exceptional circumstances for the medicinal product Adzynma, indicated for the treatment of ADAMTS13 deficiency in people with congenital thrombotic thrombocytopenic purpura (cTTP). The applicant for this medicinal product is Takeda Manufacturing Austria AG. The active substance of Adzynma is recombinant ADAMTS13 (rADAMTS13). Apadamtase alfa was approved for medical use in the European Union in August 2024.
References
External links
Medical treatments
Orphan drugs
Recombinant proteins
Drugs developed by Takeda Pharmaceutical Company | Apadamtase alfa | [
"Biology"
] | 649 | [
"Recombinant proteins",
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75,445,295 | https://en.wikipedia.org/wiki/Spider-Boy | Spider-Boy (Bailey Bartholomew Briggs) is a superhero appearing in American comic books published by Marvel Comics. Created by writer Dan Slott and artist Humberto Ramos, the character first appeared in Spider-Man vol. 4 #7 (April 2023). He is a child superhero with spider-like abilities. He was erased from existence and forgotten by everyone who knew him before being brought back. The character is also an ally of the superhero Peter Parker / Spider-Man and Gwen / Kidpool, and the main character of the comic book series Spider-Boy and Kidpool & Spider-Boy.
Development
Concept and creation
Spider-Boy creator Dan Slott stated "So, the idea came from when we were writing. I said to my editor, "Wouldn't it be funny if there was one more guy? And now, no one remembers him." And we started talking about who that [could] be, what kind of character they would be. I was pitching really hard for it to be Spider-Boy. Why? This all-new character would be the youngest spider character we'd ever done because both Miles and Peter, when they got bit, were teenagers. I thought it would be really fun to see the adventures of a preteen Spider-Man character, someone Spider-Man won't want running around. It's child endangerment [laughs]. If you're Spider-Man, you're all about responsibility, and what kind of responsible hero would you be if you let this nine or ten-year-old kid run around and fight crime? So that's kind of where that came from." Slott later said Spider-Boy was created to be an entertaining Spider-Man supporting character, but became popular enough to get his own comic series.
Publication history
Spider-Boy debuted in Spider-Man vol. 4 #7 (April 2023), created by Dan Slott and Humberto Ramos. He later appeared in the 2023 Edge of Spider-Verse series, and in the 2023 Spider-Boy series, his first solo comic book series. The first issue was released on November 1, 2023. The second issue was released on December 20, 2023. The third issue was released on January 31, 2024. He appeared in the 2023 Superior Spider-Man series, and in the 2023 Marvel Unlimited exclusive Infinity Comic series. The fourth issue of Spider-Boy was released on February 21, 2024.
Fictional character biography
Bailey Briggs was originally a normal boy before being kidnapped by Madame Monstrosity. He and fellow prisoner Eli Hartman are respectively fused with a spider and an elephant and rhinoceros, with Eli being dubbed "Hellifino". Eventually, Bailey managed to escape and, after training with Daredevil to gain more control over his powers became Spider-Boy, Spider-Man's sidekick, getting his costume from Mister Fantastic.
In "End of the Spider-Verse", following the defeat of Shathra and Morlun, Bailey is among their victims who are resurrected. After realizing that nobody remembers his existence, he leaves and ends up living at a F.E.A.S.T. building after saving a young girl named Christina Wu from Mister Negative's Inner Demons.
After helping Spider-Man and the Gold Golbin defeat Elektro after Spider-Man overloaded his spider-sense, Bailey managed to convince him that he was his sidekick while reminiscing about his previous encounters with Killionaire and Big Wheel before going out to fight the bowling bandit Gutterball.
As Spider-Man and Spider-Boy fight Gutterball, Madame Monstrosity sees a newspaper talking about the latter and decides to recapture him, sending her elephant/rhinoceros henchman Hellifino to do so. Spider-Boy tries to get through to him, knowing that he was previously his friend Eli. This causes Hellifino to reconsider his actions and let Spider-Boy go, telling Madame Monstrosity that he escaped. Later, during a Thanksgiving parade, Spider-Boy takes Christina up a building where they meet Squirrel Girl and battle Balloon Man.
At the F.E.A.S.T. building, Bailey and Christina Wu help set up for Christmas before battling Taskmaster. They stop him, but he manages to obtain the Super-Adaptoid's left hand for Killionaire's use. On Christmas Day, Christina gives Bailey a picture of him and his mother.
Spider-Boy later battles Toy Soldier, a sentient action figure that Killionaire had Shannon Stillwell create by reverse-engineering the Super-Adaptoid technology and can replicate the powers of the Avengers. However, Spider-Boy convinces him to turn against Killionaire and become a hero after he proves to be worthy of wielding Mjolnir. Sometime later, Spider-Boy and Thor battle the Asgardian spider Klöpp before learning that it is Ulik's pet and reuniting the two.
During the "Gang War" storyline, Spider-Boy saves a police officer from the Inner Demons by using his paralyzing venom on him. Then he works to defend the F.E.A.S.T. building from Vermin and his clones. Spider-Boy is among the heroes who assist Spider-Man, Miles Morales, Spider-Woman, She-Hulk, and Daredevil in fighting Madame Masque.
It's movie night at the F.E.A.S.T. Center. Aunt May states that her movie choice is Fast Car Family Five, which is a favorite of Peter Parker. Spider-Boy and Christina Wu head to Lucky Lane's Bowling Alley to go bowling. Then he later goes on patrol where he finds Spider-Man and Miles Morales fighting the Vulturions. Spider-Boy later encounters Boy-Spider, a clone of him created by Madame Monstrosity who is more spider than human. After fleeing, Boy-Spider is calmed down by Monstrosity's servant Tabby, who is revealed to be Bailey's mother Tabitha Briggs.
While out of webs, Spider-Boy encounters Spider-Woman while dodging some drones. While Spider-Woman does not remember the day when she helped Spider-Boy defeat Red Heron, she was surprised that Spider-Boy remembered Gerry. Both of them discover that the drones were being controlled by Screwball. who combines them into one giant robot. Spider-Woman defeats the giant robot and uses one of the drones to track down Screwball. When Screwball tries to flee, Spider-Woman and Spider-Boy subdue Screwball and leave her for the police.
As Bailey tries to have lunch at PS 41 Greenwich Village, he gets surprised by a teacher and knocks him down causing Bailey to flee while apologizing. While going over the previous PS locations, his spider-senses on the pen he's holding reveals to him that Christina will be targeted by Madame Monstrosity and Hellifino. Despite his efforts, Madame Monstrosity and Hellifino succeed in kidnapping Christina and fusing her with a pigeon.
While fighting Madame Monstrosity to rescue Christina, Spider-Boy learns that Tabitha is his mother and that she does not remember him. He is later kidnapped by Monstrosity, who plans to further experiment on him to improve her Humanimals. However, Christina manages to contact Miles Morales, Squirrel Girl, Captain America, Thor, and Toy Soldier to rescue them. Madame Monstrosity transforms into a Chimera of different animal specimens and attacks the heroes before being taken away by the High Evolutionary who plans to experiment on her.
After Madame Monstrosity is defeated, her husband Jeremy Stillwell, her former henchmen Squeakerton and Mr. Cricket, Spider-Man, and Toy Soldier, modify the transformation chamber to successfully undo the Humanimal transformations. However, Boy-Spider, Jeremy, and Hellifino are unable to be restored, so they choose to live on the Farm with Tabitha. After heading to the F.E.A.S.T. building and getting a picture of him with his mother, Spider-Boy is ambushed by Puzzle Man who puts Spider-Boy through a maze. After Spider-Boy solves a crossword puzzle and Puzzle Man accidentally erases another part of the picture, Spider-Boy transforms and goes after him. With help from the readers, Spider-Boy catches up to Puzzle Man and breaks his pencil. As Spider-Boy wonders if he did something to cause everyone to not remember him as he sees the Simms Tower, Madame Web, Silk, and Lady Araña are working on how to deal with their new Spider-Friend. Spider-Boy shows up to tell Lady Araña that he brought him back wrong and that he needs her help to fix it.
Lady Araña, Silk, and Madame Web attempt to restore the universe's memories of Spider-Boy, but accidentally cast a spell that sends him through the Web of Life and Destiny. As Bailey travels the universe, visiting Earth-67, Earth-51778, Earth-51914, Earth-982, and Earth-92131 in the process, Lady Araña and Silk begin to remember his existence which led to him accidentally getting sucked into the Web of Life and Destiny. Spider-Man is informed of what happened and donates "threads" to rescue Spider-Boy. This also restores the universe's memories of him, with Madame Web stating that there will be a price for this.
Afterwards, Bailey returns to school and begins learning everything that happened while he was missing. Tabitha also joins the F.E.A.S.T. staff and learns of Bailey's secret identity, but allows him to continue being a superhero. Meanwhile, Bullseye and an unnamed female ninja take interest in him and obtain Daredevil's Golden Fang Trophy. In response, Spider-Boy and Daredevil pursue Bullseye to Madripoor. Arriving in Madripoor, Spider-Boy and Daredevil had to obtain a Golden Fang Trophy by defeating the sumo wrestler Enormo and his student Hulkette. Then they head to the location where the Challenge of the Jade Dragon tournament is where their appearance surprises Bullseye and Spider-Girl. Despite the claims of Enormo and Hulkette, the Gaping Maw will only allow them to enter if Spider-Boy and Daredevil are defeated. Spider-Boy and Daredevil make plans to make sure they stay in the tournament. They are paired up against El Gigante and La Mota where Spider-Boy's bite on La Mota caused El Gigante to yield. After Bullseye and Spider-Girl's victory, Spider-Boy goes out to buy some ramen before the next match and ends up dining with Spider-Girl. Spider-Boy then recalls that Spider-Girl is actually Funhouse, a shapeshifting villain of his. In a flashback, Spider-Girl and Ms. Marvel had subdued Stegron who was in the middle of stealing dinosaur bones when Bullseye dispatched Funhouse to attack. Spider-Boy finds her able to get a good look at Ms. Marvel and Stegron enough to copy their abilities. When she tries to copy the abilities of Spider-Boy, Funhouse lost control. Back in the present, Spider-Boy compared the incident to when Rogue copied the abilities of Ms. Marvel and that he can hook her up with Rogue and the X-Men when the tournament is over. After checking in with Tabitha, Spider-Boy finds that Hulkette has arrived as she tells Spider-Boy and Funhouse that they are needed back at the arena. Spider-Boy receives a new costume from Daredevil as they are paired up against Bengal and Tigris.
Spider-Boy then meets Gwen / Kidpool, a girl the same age as him who falls in love at first sight with him, the two fighting Archon and Stegron the Dinosaur Man.
Powers and abilities
Spider-Boy possesses superpowers similar to those of Spider-Man. He can transform into a spider hybrid at will, gaining paralyzing venom, enhanced vision, and the ability to communicate with spiders. Additionally, he has a variety of the Spider-Sense that manifests as psychometry.
Supporting characters
Enemies
Spider-Boy has his own rogues gallery:
Other versions
An alternate future timeline variant of Spider-Boy appears during the Venom War event.
Reception
Critical response
Casey Donahue of Screen Rant named Bailey Briggs one of the best new heroes of 2023. D. R. Bickham of Comic Book Resources called Bailey Briggs one of the most interesting incarnations of Spider-Man, writing, "While his youth, quirkiness, and awkward similarities to his mentor make him immediately endearing to fans, another contributing factor to Spider-Boy's newfound popularity and staying power lies in his unique rogues gallery." George Marston of Newsarama referred to Bailey Briggs as a one of Marvel's newest breakout characters.
Impact
In 2023, the introduction of Bailey Briggs as Spider-Boy in Spider-Man vol. 4 #7 was credited as one of the main reasons the comic book sold out. Matt Devoe of ComicBook.com ranked the comic book 1st in their "Top 10 Comic Books Rising in Value in the Last Week Include Midnight Sons and Tons of Spider-Verse" list. His appearance in Edge of Spider-Verse #3 was also credited as one of the key reasons the comic book sold out.
Literary reception
Volumes
Spider-Boy (2023)
Diamond Comic Distributors reported that Spider-Boy #1 was the 3rd top advance-reordered comic book by retailers between November 20 to November 6, 2023. ComicHub reported that Spider-Boy #1 was the best-selling comic in November 2023. The ComicHub Top 200 Comics sales chart reflects sales data collected from the ComicHub system at comic shops across the globe that sell American comics. This report was created based on information from more than 125 stores that used the ComicHub system during the reporting period.
Sayantan Gayen of Comic Book Resources called Spider-Boy #1 a "positive debut issue," asserting that it offers the freshest take on an old formula from Marvel in recent history. He praised the potential for the character, noting that Bailey's future looks bright if the creators invest the necessary love to help him grow. Matthew Aguilar of ComicBook.com gave Spider-Boy #1 a score of 4 out of 5 stars, praising the emotional depth of Bailey's origin story and the poignant reunion that unfolds, calling it a "heartfelt" experience. He noted that the villains in the series have an appealing absurdity, which adds to its charm, with artist Paco Medina and colorist Erick Arciniega effectively embracing this whimsical style in their artwork and character designs. Aguilar also highlighted the entertaining second story, "Balloonacy," by Ty Templeton and Dee Cunniffe, appreciating the inclusion of Squirrel Girl and Tippy-Toe. He remarked that when Spider-Boy takes center stage, the series evokes a unique quality that feels special, leaving him eager to see where the story goes next.
References
Characters created by Dan Slott
Comics characters introduced in 2023
Fictional characters with precognition
Fictional genetically engineered characters
Fictional hybrids
Genetically engineered characters in comics
Marvel Comics characters who can move at superhuman speeds
Marvel Comics characters with accelerated healing
Marvel Comics characters with spider powers
Marvel Comics characters with superhuman senses
Marvel Comics characters with superhuman strength
Marvel Comics male superheroes
Marvel Comics mutates
Marvel Comics teenage superheroes
Spider-Man characters
Spiders in popular culture
Superheroes with alter egos
Teenage characters in comics | Spider-Boy | [
"Biology"
] | 3,220 | [
"Fictional hybrids",
"Hybrid organisms"
] |
75,446,479 | https://en.wikipedia.org/wiki/Collar%20neighbourhood | In topology, a branch of mathematics, a collar neighbourhood of a manifold with boundary is a neighbourhood of its boundary that has the same structure as .
Formally if is a differentiable manifold with boundary, is a collar neighbourhood of whenever there is a diffeomorphism such that for every , .
Every differentiable manifold has a collar neighbourhood.
References
Differential topology
Manifolds | Collar neighbourhood | [
"Mathematics"
] | 75 | [
"Space (mathematics)",
"Topology stubs",
"Topological spaces",
"Topology",
"Differential topology",
"Manifolds"
] |
75,446,547 | https://en.wikipedia.org/wiki/Caltongate | Caltongate (now known as New Waverley Square) is the largest city centre redevelopment project in Edinburgh since the 18th century. First proposed in 2005, it took 9 years to be given the go-ahead by Edinburgh Council, after disruption caused by the 2007–2008 financial crisis. The name Caltongate combines Canongate and Calton Hill, as the area lies on Canongate, and faces directly onto Calton Hill. Caltongate lies within the Old Town, Edinburgh, which was recognised as a UNESCO World Heritage site in 1994. Construction began in 2014 and is yet to be completed.
History
Context
This section refers to the post-18th-century context relevant to the Caltongate development. If looking for a more comprehensive review of the history of this region, section 3 of this article is recommended.
In 1817, the site of the Caltongate development on New Street was initially built up as the New Street Gasworks along with the rise of coal gas alongside the industrial revolution. Due to a subsequent rise in coal pollution as well as the absence of a Scottish Monarchy and the dissolution of the Parliament of Scotland after the Acts of Union 1707, the status of Canongate was reduced and it became a primarily working-class neighbourhood. This is reflected by the high level of investment in social housing in Canongate in the first half of the 20th century.
By 1928 the New Street Gasworks had been demolished, and this area was turned into a Bus Depot. By 1996, the bus depot was no longer in use and was the host of The Bongo Club run by the arts charity Out of the Blue. In December 2003, full planning permission was granted to redevelop the former New Street Bus Depot. In September 2006, demolition of the bus depot began.
The construction of the modern Scottish Parliament Building down the road in Holyrood Palace and the neighbouring £50 million City of Edinburgh Council headquarters set a precedent for modern development in the Canongate area. A questionnaire directed to members of the public in 2006 identified that 89% of people agreed that the area around the Caltongate site needed generation.
Development timeline
The New Street Bus Depot was purchased by Mountgrange Capital PLC for £20m in 2004, and in November 2005 the Council disposed of the Canongate Venture building, the Council Depot building and the Jeffrey Street arches to Mountgrange, which then proposed "Caltongate". Allan Murray Architects (also responsible for the controversial construction of St James Quarter) won the contract to design the development. There was a series of pre-planning activities which took place across the years 2004-2005 that consulted "key stakeholders, "advisors" and "various interest groups". A masterplan was also written to "maximise the opportunity for the area" This led to the proposed inclusion of a more detailed planning process and other physical elements to Caltongate such as affordable housing. This would supposedly be a £300 million scheme.
Details of the proposal were first publicised in the Edinburgh Evening News on 3 October 2005, and promised to link the Council Headquarters, Scottish Parliament, Holyrood North and the Moray House Campus. It envisioned an "increased population", "a major new public square" and a regeneration of Canongate. There was a "four-year battle with heritage groups" until it secured planning on the 6th February 2008. However, as an aftermath of the 2007–2008 financial crisis, Mountgrange went into administration after a withdrawal of support from the Bank of Scotland and a slump in the property market, leading to a halt in the construction of Caltongate.
The project was taken over by Artisan Real Estate Investors in 2009, and went through a series of adaptations and was only narrowly voted through by the council on the 29th January 2014 on an 8:6 split. The proposal diverted from its original form, offering 40% less housing and the intended larger commercial buildings had been 'broken up into more intimate individual units, improving the overall look and feel of the area'. By 2014 it had been reduced from a £300 million to a £150 million plan. At this point, the project was rebranded from 'Caltongate' to 'New Waverley'.
The construction of 'New Waverley' began in late 2014. The Waverley arches under Jeffrey Street started to host businesses in early 2016. Arches Artisan Real Estate Investors were legally entitled to demolish the listed buildings Sailors' Ark and Canongate Venture, but they were instead into hotels, with the former opened by Adagio city in 2016 and the latter by BrewDog in 2021. This is indicative of the efforts of the heritage campaigners. The UK Government Hub 'Queen Elizabeth House' opened in Spring 2020. The Queensberry Apartment complex was completed in 2021 and can be found on the east side of the Caltongate development, hosting 66 new homes, mews houses and maisonettes, along with first-class retail and commercial space.
As of December 2023, there is still an empty building site where there was supposed to be a residential building. Rather than matching the original plans of 87 residential units, there have been plans set forward by Vita Group to build new purpose-built student accommodation made up of shared flats for 65 individuals as well as 224 studio bedrooms. Additionally, there have been 3 affordable housing units allocated as well as 277 sqm of ground floor space for a commercial or community unit.
Controversy
The development proposal was met with backlash by some members of the community. Since the 1980s, the threat of Thatcher's Housing Act 1980 as well as other neighbouring modern developments such as the City of Edinburgh Council headquarters in 2006 has meant that the historically working-class community is sceptical of modern development.
Pre-2008 economic crisis
Anti-Canongate Organisations
As an initial reaction to the proposal in 2005, there were organisations, both newly established and pre-existing, that campaigned as well as made statements or reports against the proposal. Expressed concerns often encompassed the following:
Aesthetic concerns
Class-based concerns
Heritage concerns
Save Our Old Town Campaign (SOOT)
Also known as the Canongate Community Forum (CCF), SOOT was formed in 2005 as a response to the Caltongate development proposal, after approval from the Scottish Community Action Research Fund (SCARF). The primary aim expressed in their report was their requirement for "genuine community consultation". Notably, The SOOT campaigners used "highly moralised language to challenge Caltongate's supporters and demand their rights to consultation." Programmes were funded by SCARF for public remembrance: walking tours, lectures, films on the history of Canongate, along with public forums where citizens could discover their "intangible heritage".
The Cockburn Association
The Cockburn Association, an independent charity dedicated to architectural conservation issued a statement addressing their primary concerns. Notably, they criticised:
The choice of materials, predominantly horizontal roofscapes, demolition of listed buildings, lack of Waverly Valley form and excessively high development.
The demolition of the Canongate Venture.
The loss of a panoramic view.
The lack of attempt to balance the requirements of investors with local and heritage concerns.
UNESCO mission 2008
The Edinburgh World Heritage trust lobbied UNESCO in 2008, leading to their sending of a mission to the Caltongate site. In their subsequent report, UNESCO reported that Edinburgh's heritage sites were not in danger and that the World Heritage Committee was concerned about the demolition of the two listed buildings. They also asked for a buffer zone around the World Heritage Site, which has not been taken into action either by the planning committee and Edinburgh World Heritage.
Andrew Holmes, the director of development for the city of Edinburgh Council from the years 2000–2008, criticised UNESCO for its communication only within its "own coterie" via "a self-appointed elite".
Historic Scotland
Despite expressing earlier concerns over the scheme, Historic Scotland was supportive of the scheme by 2008, under the condition that they would work closely with the developers to ensure that the proposals were sensitive to the historic environment and the World Heritage property.
Response to controversy
One universal criticism expressed by all organisations was their lack of communication with the local community. In response to this, the council led programmes of community engagement including an invitation-only Planning Stakeholders Workshop in March 2006, preceding an open-door Community Planning Day in April 2006. The Caltongate Liaison Group was also organised by Mountgrange to act as a forum for residents to share their concerns. Mountgrange met with Historic Scotland, Edinburgh World Heritage, Cockburn Association, Old Town Association and Architecture and Design Scotland to discuss the heritage implications of the Caltongate proposals.
This video was also handed out in DVD form to residents and organisations in 2007 to convince them of the benefits of the Caltongate development.
Post-2008 economic crisis
After Mountgrange went into administration, the construction of Caltongate was paused, which provided a second lease of life to the anti-Caltongate campaign.
Post 2008 Anti-Caltongate campaigns
By March 2017, 5985 people had signed a petition which had begun in 2014, challenging the council's decision to approve the "Caltongate/New Waverley development". In the spirit of collaboration and innovation, there was even an alternative proposal put forward by ANTA architecture, that kept the interests of "citizens, investors and future occupants" at heart. This employed an aesthetic similar to what is already seen in Edinburgh's Old Town and readopted arcades.
UNESCO Decision 2011
After the economic crash, UNESCO issued a new decision, urging the State Party to do all it can to ensure that revised plans are produced for any future development of the Caltongate site that respects the spatial layout of the Old Town.
Canongate Venture
Canongate Venture (North Canongate Infant School) was due to be replaced as part of a hotel and conference centre complex. New research emerged indicating the historical significance of this school in shaping the Children's Act of 1908. Due to this, there was pressure to keep the building in order to preserve its cultural significance. Sean Bradley, chairman of the Edinburgh Old Town Development Trust, proposed that the building should become a publishing hub combined with a literacy centre. The building was ultimately not demolished and in December 2021, it re-opened as a hotel owned by pub chain BrewDog.
The role of class
The topic of class also sparked scholarly debate on Caltongate. Scholar Tooley argues that the upper-class heritage supporters fought in the name of 'aesthetic defence', whilst the working-class urban residents fought to keep their area working class. This divide based on class is also seen in the media. In the Scotsman, non-residents are "heavily critical of the design", whilst local residents criticise the "provision for housing".
Caltongate proponents
Artisan managing director Lukas Nakos said the development marked "a significant milestone in the evolution of one of the most challenging city centre developments anywhere in the UK." Donald Anderson, city council leader from 1999 to 2007, commented that the area had been "intended for regeneration", especially when considering the context of the recently built neighbouring Parliament building.
Councillor Joanna Mowat also famously said that the plans were "not hideous enough to reject." This was a quote used across news articles from various sources to comment on the mood surrounding the Caltongate project.
Notable figures
Edinburgh Greens councillor Nigel Bagshaw described the development as 'alien' to the character of the Old Town.
A letter was written in March 2014, addressed to readers of The Scotsman by writers Irvine Welsh, Alexander McCall Smith and Janice Galloway, sculptor Alexander Stoddart, artist John Byrne (playwright), and architect James Simpson. This letter criticises the development's "assault on its heritage" and registers "no confidence in the City Planning Department in its current form and membership".
Design
Masterplan design
The main changes published in Mountgrange's masterplan included:
A new walkway between Calton Road and Regent Walk called Parliament Way.
A landmark office block between Jeffrey Street and Cranston Street and a conference centre for Parliament Way.
Construction of a five star hotel using the Old Sailor's Ark as a façade.
A major new square Connecting Canongate, East Market Street and Calton Hill.
Redevelopment of East Market Street and the arches below Jeffrey Street.
Residential flatted accommodation stretching from Canongate to Calton Road on the Eastern side of the new square.
The masterplan also promised to allocate 25% of its housing options as affordable housing. To substitute the gap left by the demolished New Street bus depot, there was a proposal for a £100,000 arts project to temporarily occupy the given space. This however was never realised.
The exterior of Waverley square features natural sandstone, metal and brick. The design would "create new buildings and spaces of the highest architectural and urban design quality that conserve and reinforce the existing historic and landscape context."
Awards
The New Waverley (Caltongate) development won three place-making awards in 2017 - including best regeneration project for both the Scottish Property Awards and the Royal Institution of Chartered Surveyors.
Criticism
The design has been criticised for having adopted "aesthetic governmentality": legitimising social hierarchies and forms of exclusion. Tooley argues that the aesthetic transformation led to 'spatialised forgetting', where the Caltongate communal identity was overridden by a frame of neoliberal urbanism. In other words, the newfound modern aesthetic can be seen as a political attack on a working-class neighbourhood.
The design was also criticised for its modernity, for instance, it was described as a "massive, stale, sterile modernist confection of concrete". which contradicts the historical image of Edinburgh Old Town. As a response, the design features sandstone-coloured cladding, referencing the natural red sandstone prominently found in the architecture of Edinburgh. Anti-Caltongate campaigners also critiqued the design of Caltongate as a direct response to Caltongate leaders' denigration of the neighbourhood's former "dingy" appearance.
Sustainability
The Caltongate masterplan proposed a ground source heating and cooling system. This would reduce carbon emissions by 30%. Additionally, 30% of materials would be sourced within a 45-mile radius and a Construction Waste Minimisation Plan targeted to divert 80% or more of waste away from ultimate disposal by landfill through promoting the reduction, reuse and recycling of waste.
Aftermath
The Caltongate/New Waverley development moved out existing tenants of Canongate, with the tenements of 221-229 Canongate demolished after 2014. The promised 25% of affordable housing has yet to be built along with the five-star hotel as of 2023. There is an empty lot of land that will supposedly host student accommodation in the future.
Queen Elizabeth House, the Government hub, is said to have moved almost 3000 civil service jobs into New Waverley Square.
References
Redevelopment
Buildings and structures in Edinburgh | Caltongate | [
"Engineering"
] | 3,025 | [
"Construction",
"Redevelopment"
] |
75,446,827 | https://en.wikipedia.org/wiki/Volga%20149.200 | According to Snopes, an American myths and rumors factcheck website analysis, Russian-owned websites copy-paste pro-Russian propaganda about Russia's alleged aims "to prevent pointless bloodshed among by Ukrainian soldiers", mentioning 149.200 'Volga', a frequency which is said to offer Ukrainian soldiers a chance to surrender to Russian forces. In 2024 when French President Emmanuel Macron made statements about the possibility of French troops being deployed to Ukraine, posters began to appear near the French Embassy in Moscow and public transport stations around the embassy. The posters depicted an image of the commander of the French SS division Charlemagne, Edgar Puaud and text in both French and Russian which read: "Frenchmen, do not repeat the mistakes of your ancestors; their fate is well-known" followed by "Call Volga 149.200".
References
Radio spectrum
Russian invasion of Ukraine
Ukrainian prisoners of war | Volga 149.200 | [
"Physics"
] | 182 | [
"Radio spectrum",
"Spectrum (physical sciences)",
"Electromagnetic spectrum"
] |
75,447,097 | https://en.wikipedia.org/wiki/Vacuum%20%28journal%29 | Vacuum is a quarterly peer-reviewed scientific journal published by the Elsevier. Founded in 1951, the journal covers the fundamental research and technical advances in vacuum engineering, materials science and surface science. Its editor-in-chief is Lars Hultman (Linköping University).
According to the Journal Citation Reports, the journal has a 2023 impact factor of 3.8.
References
External links
Vacuum
Elsevier academic journals
English-language journals
Academic journals established in 1951
Quarterly journals
Plasma science journals | Vacuum (journal) | [
"Physics",
"Materials_science"
] | 99 | [
"Materials science stubs",
"Plasma science journals",
"Plasma physics",
"Materials science journals",
"Vacuum",
"Materials science journal stubs",
"Matter"
] |
75,448,042 | https://en.wikipedia.org/wiki/Brigimadlin | Brigimadlin (BI-907828) is a small molecule MDM2-TP53 inhibitor developed for liposarcoma.
References
Small-molecule drugs
Drugs developed by Boehringer Ingelheim
Fluoroarenes
Chloroarenes
Cyclopropyl compounds
Lactams
Indazoles
Heterocyclic compounds with 4 rings
Spiro compounds
Carboxylic acids | Brigimadlin | [
"Chemistry"
] | 86 | [
"Organic compounds",
"Carboxylic acids",
"Functional groups",
"Spiro compounds"
] |
75,448,147 | https://en.wikipedia.org/wiki/Mikhail%20Marov | Mikhail Marov (28 July 1933 – 30 November 2023) was a Russian astronomer. He was born in Moscow on 28 July 1933, and died on 30 November 2023, at the age of 90.
Awards and honors
Lenin Prize (1970)
Prix Galabert der Société Française d'astronautique (1973)
USSR State Prize (1980)
Alvin Seiff Award (2013)
Demidov Prize (2015)
Order of Honour (2015)
Order of Friendship (2015)
Keldysch-Goldmedaille der RAN (2016)
References
1933 births
2023 deaths
Soviet astronomers
Russian astronomers
Members of the USSR Academy of Sciences
Members of the Russian Academy of Sciences
Recipients of the USSR State Prize
Recipients of the Lenin Prize
Recipients of the Order of Honour (Russia)
Demidov Prize laureates
Bauman Moscow State Technical University alumni
Scientists from Moscow | Mikhail Marov | [
"Astronomy"
] | 171 | [
"Astronomers",
"Astronomer stubs",
"Astronomy stubs"
] |
75,448,824 | https://en.wikipedia.org/wiki/Mavorixafor | Mavorixafor, sold under the brand name Xolremdi, is a medication used for the treatment of WHIM syndrome. It is a CXC chemokine receptor 4 antagonist. It is taken by mouth. It was developed by X4 Pharmaceuticals.
The most frequently reported adverse reactions include thrombocytopenia (low platelet counts), rash, rhinitis (stuffy nose), epistaxis (nosebleed), vomiting, and dizziness.
Mavorixafor was approved for medical use in the United States in April 2024. The US Food and Drug Administration (FDA) considers it to be a first-in-class medication.
Medical uses
Mavorixafor is indicated in people twelve years of age and older with WHIM syndrome (warts, hypogammaglobulinemia, infections and myelokathexis) to increase the number of circulating mature neutrophils and lymphocytes.
Adverse effects
Mavorixafor is expected to cause harm to the baby.
History
The effectiveness of mavorixafor was evaluated in a 52-week, randomized, double-blind, placebo-controlled trial that enrolled 31 adolescents and adults with WHIM syndrome (NCT03995108). Mavorixafor improved absolute neutrophil counts and absolute lymphocyte counts, assessed over a 24-hour period four times throughout the study. Absolute neutrophil counts below 500 cells/μL and absolute lymphocyte counts below 1000 cells/μL are associated with an increased risk of infections. The average length of time over 24 hours that counts were above these levels was significantly longer with mavorixafor compared to the placebo group (15.0 hours compared to 2.8 hours for absolute neutrophil counts; 15.8 hours compared to 4.6 hours for absolute lymphocyte counts).
Society and culture
Names
Mavorixafor is the international nonproprietary name.
Research
Mavorixafor is in clinical trials for melanoma and renal cell carcinoma.
References
External links
Benzimidazoles
Tetrahydroquinolines
Amines | Mavorixafor | [
"Chemistry"
] | 466 | [
"Amines",
"Bases (chemistry)",
"Functional groups"
] |
75,448,891 | https://en.wikipedia.org/wiki/DA-1241 | DA-1241 is an experimental GPR119 receptor agonist developed by the South Korean company Dong-A ST for non-alcoholic steatohepatitis and type 2 diabetes.
References
Receptor agonists
Experimental drugs developed for non-alcoholic fatty liver disease
Experimental diabetes drugs
Pyrimidines
Piperidines
Phenol ethers
Fluoroarenes
Oxadiazoles
Isopropyl compounds | DA-1241 | [
"Chemistry"
] | 84 | [
"Receptor agonists",
"Neurochemistry"
] |
75,449,058 | https://en.wikipedia.org/wiki/INZ-701 | INZ-701 is a recombinant ENPP1 enzyme developed to treat some genetic disorders that prevent normal production of ENPP1. It is developed by Inozyme Pharma.
References
Enzymes used as drugs | INZ-701 | [
"Chemistry"
] | 48 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
75,449,237 | https://en.wikipedia.org/wiki/LB54640 | LB54640 is a small molecule melanocortin 4 receptor agonist developed by LG Chem Life Sciences for hypothalamic obesity. Unlike the older drug with the same mechanism of action, setmelanotide, it can be taken by mouth.
References
Melanocortin receptor agonists | LB54640 | [
"Chemistry"
] | 67 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
75,449,252 | https://en.wikipedia.org/wiki/Locally%20recoverable%20code | Locally recoverable codes are a family of error correction codes that were introduced first by D. S. Papailiopoulos and A. G. Dimakis and have been widely studied in information theory due to their applications related to distributive and cloud storage systems.
An LRC is an linear code such that there is a function that takes as input and a set of other coordinates of a codeword different from , and outputs .
Overview
Erasure-correcting codes, or simply erasure codes, for distributed and cloud storage systems, are becoming more and more popular as a result of the present spike in demand for cloud computing and storage services. This has inspired researchers in the fields of information and coding theory to investigate new facets of codes that are specifically suited for use with storage systems.
It is well-known that LRC is a code that needs only a limited set of other symbols to be accessed in order to restore every symbol in a codeword. This idea is very important for distributed and cloud storage systems since the most common error case is when one storage node fails (erasure). The main objective is to recover as much data as possible from the fewest additional storage nodes in order to restore the node. Hence, Locally Recoverable Codes are crucial for such systems.
The following definition of the LRC follows from the description above: an -Locally Recoverable Code (LRC) of length is a code that produces an -symbol codeword from information symbols, and for any symbol of the codeword, there exist at most other symbols such that the value of the symbol can be recovered from them. The locality parameter satisfies because the entire codeword can be found by accessing symbols other than the erased symbol. Furthermore, Locally Recoverable Codes, having the minimum distance , can recover erasures.
Definition
Let be a linear code. For , let us denote by the minimum number of other coordinates we have to look at to recover an erasure in coordinate . The number is said to be the locality of the -th coordinate of the code. The locality of the code is defined as
An locally recoverable code (LRC) is an linear code with locality .
Let be an -locally recoverable code. Then an erased component can be recovered linearly, i.e. for every , the space of linear equations of the code contains elements of the form , where .
Optimal locally recoverable codes
Theorem Let and let be an -locally recoverable code having disjoint locality sets of size . Then
An -LRC is said to be optimal if the minimum distance of satisfies
Tamo–Barg codes
Let be a polynomial and let be a positive integer. Then is said to be (, )-good if
• has degree ,
• there exist distinct subsets of such that
– for any , for some , i.e., is constant on ,
– ,
– for any .
We say that {} is a splitting covering for .
Tamo–Barg construction
The Tamo–Barg construction utilizes good polynomials.
• Suppose that a -good polynomial over is given with splitting covering .
• Let be a positive integer.
• Consider the following -vector space of polynomials
• Let .
• The code is an -optimal locally coverable code, where denotes evaluation of at all points in the set .
Parameters of Tamo–Barg codes
• Length. The length is the number of evaluation points. Because the sets are disjoint for , the length of the code is .
• Dimension. The dimension of the code is , for ≤ , as each has degree at most , covering a vector space of dimension , and by the construction of , there are distinct .
• Distance. The distance is given by the fact that , where , and the obtained code is the Reed-Solomon code of degree at most , so the minimum distance equals .
• Locality. After the erasure of the single component, the evaluation at , where , is unknown, but the evaluations for all other are known, so at most evaluations are needed to uniquely determine the erased component, which gives us the locality of .
To see this, restricted to can be described by a polynomial of degree at most thanks to the form of the elements in (i.e., thanks to the fact that is constant on , and the 's have degree at most ). On the other hand , and evaluations uniquely determine a polynomial of degree . Therefore can be constructed and evaluated at to recover .
Example of Tamo–Barg construction
We will use to construct -LRC. Notice that the degree of this polynomial is 5, and it is constant on for , where , , , , , , , and : , , , , , , , . Hence, is a -good polynomial over by the definition. Now, we will use this polynomial to construct a code of dimension and length over . The locality of this code is 4, which will allow us to recover a single server failure by looking at the information contained in at most 4 other servers.
Next, let us define the encoding polynomial: , where . So, .
Thus, we can use the obtained encoding polynomial if we take our data to encode as the row vector . Encoding the vector to a length 15 message vector by multiplying by the generator matrix
For example, the encoding of information vector gives the codeword .
Observe that we constructed an optimal LRC; therefore, using the Singleton bound, we have that the distance of this code is . Thus, we can recover any 6 erasures from our codeword by looking at no more than 8 other components.
Locally recoverable codes with availability
A code has all-symbol locality and availability if every code symbol can be recovered from disjoint repair sets of other symbols, each set of size at most symbols. Such codes are called -LRC.
Theorem The minimum distance of -LRC having locality and availability satisfies the upper bound
If the code is systematic and locality and availability apply only to its information symbols, then the code has information locality and availability , and is called -LRC.
Theorem The minimum distance of an linear -LRC satisfies the upper bound
References
Cryptography
Information theory
Error detection and correction | Locally recoverable code | [
"Mathematics",
"Technology",
"Engineering"
] | 1,263 | [
"Cybersecurity engineering",
"Cryptography",
"Telecommunications engineering",
"Reliability engineering",
"Applied mathematics",
"Error detection and correction",
"Computer science",
"Information theory"
] |
75,449,638 | https://en.wikipedia.org/wiki/CRISPR-associated%20transposons | CRISPR-associated transposons or CASTs are mobile genetic elements (MGEs) that have evolved to make use of minimal CRISPR systems for RNA-guided transposition of their DNA. Unlike traditional CRISPR systems that contain interference mechanisms to degrade targeted DNA, CASTs lack proteins and/or protein domains responsible for DNA cleavage. Specialized transposon machinery, similar to that of the well characterized Tn7 transposon, complexes with the CRISPR RNA (crRNA) and associated Cas proteins for transposition. CAST systems have been characterized in a wide range of bacteria and make use of variable CRISPR configurations including Type I-F, Type I-B, Type I-C, Type I-D, Type I-E, Type IV, and Type V-K. MGEs remain an important part of genetic exchange by horizontal gene transfer and CASTs have been implicated in the exchange of antibiotic resistance and antiviral defense mechanisms, as well as genes involved in central carbon metabolism. These systems show promise for genetic engineering due to their programmability, PAM flexibility, and ability to insert directly into the host genome without double strand breaks requiring activation of host repair mechanisms. They also lack Cas1 and Cas2 proteins and so rely on other more complete CRISPR systems for spacer acquisition in trans.
Natural structure and function
CRISPR-associated transposons are similar to the Tn7 transposon which functions with a cut and paste mechanism. It contains a heteromeric transposase consisting of TnsA and TnsB proteins, and a regulator protein TnsC. Structural analysis has shown binding of the TnsB protein and sequence specific motifs on the ends of the transposon which allows for excision and mobility. Targeting for integration is done by the TnsD or TnsE proteins which preferentially target safe sites within the host chromosome or mobile elements (plasmids or bacteriophages), respectively. TnsE is not found in CASTs but a TnsD homolog, TniQ, is present and functions to bridge the gap between the transposase and CRISPR-Cas. Multiple CRISPR types have been found to associate with transposons with two of the most studied being Type I-F, which makes use of a multi-subunit effector (Cascade), and Type V-K, which makes use of a single Cas12k effector. In both cases, Tn7 transposons have evolved to make use of these effectors to create R loops for site-specific integration. While TnsA is present in Type I-F systems, it is notably absent in Type V-K systems which showed higher off-target integrations during initial characterization.
Type IF-3
A Type IF-3 CAST (Tn6677) was initially identified in Vibrio Cholerae and has been extensively studied. This system contains proteins TnsA, TnsB, and TnsC that complex with Cas6, Cas7, and a Cas5-Cas8 fusion through interactions with TniQ. Initial integration steps include TniQ-Cascade binding at the target site and TnsA and TnsB excision of the transposon, which is followed by TnsC binding to TniQ and transposase binding to TnsC. There can be off-targeting prior to this final step, but TnsB and TnsC binding leads to a final proofreading step to maintain a high on-target percentage. Tn6677 integration has been validated at near 100% on-target efficiency at site specific locations in multiple points in the host genome. Other systems have also been characterized and validated in this class with varying ranges of efficiency, and include orthogonal systems for multiplexed insertions up to 10kb.
A unique characteristic of Type IF-3 systems is the presence of self-targeting guide RNA that are used to target the host chromosome. These systems have privatized the corresponding spacers through the use of atypical crRNA that prevent endogenous Type 1F systems from using the guides and their interference mechanisms to degrade the host. Another privatization mechanism is the use of mismatch tolerance allowing only CAST systems to target locations in the genome without an exact match to the spacer.
Type V-K
A Type V-K system was originally characterized from a cyanobacteria, Scytonema hofmanni, and contains a single Cas effector, Cas12k, that functions with a tracrRNA. This system functions similarly to Tn7 but does not have a TnsA protein which can result in off-targeting and chimera formation during over-expression. The Cas12k and tracrRNA complex bind to the target site and TnsC is polymerized directly adjacent prior to TniQ attachment and TnsB recognition and integration. While these systems use traditional tracrRNA characteristic of Type II CRISPR systems, they can also target with short crRNA located adjacent to the transposon end. Type V-K spacers preferentially target locations near tRNA genes, but other sites have been observed in these short crRNA guides which have been acquired by non-traditional means.
Applications in genetic engineering
CRISPR-associated transposons have been harnessed for in vitro and in vivo gene editing at different targets, in different hosts, and with different payloads. All CAST components of the Tn6677 system from Vibrio cholerae have been combined into a single plasmid and confirmed to deliver up to 10kb transposons at near 100% efficiency. This has also been shown in a community context with conjugative delivery of suicide vectors to provide antibiotic resistance or enhanced metabolic function to only a single microbe. Much of the initial characterization of these systems has been done in E. coli, but functionality has been confirmed in beta- and gammaproteobacteria with high efficiency, and in alphaproteobacteria at somewhat lower efficiency. A single plasmid Tn677 has also been shown to function in human HEK293T cells showing potential therapeutic use in the future.
References
Wikipedia Student Program
Biotechnology
Molecular biology | CRISPR-associated transposons | [
"Chemistry",
"Biology"
] | 1,249 | [
"Biochemistry",
"Biotechnology",
"nan",
"Molecular biology"
] |
66,796,669 | https://en.wikipedia.org/wiki/Katja%20Schenke-Layland | Katja Schenke-Layland (born Eisenach, Germany, March 21, 1977) is the Professor of Medical Technologies and Regenerative Medicine, Institute of Biomedical Engineering, Department for Medical Technologies and Regenerative Medicine at the University of Tübingen. She is the Director of the NMI Natural and Medical Sciences Institute at the University Tübingen in Reutlingen, Study Dean of Medical Technologies at the University of Tübingen, and Founding Director of the Institute of Biomedical Engineering at the Medical Faculty of the University Tübingen. She is also the Founding Director of the 3R Center for In Vitro Models and Alternatives to Animal Testing Tübingen.
Early research
Katja Schenke-Layland began her doctoral work in the area of heart valve tissue engineering and non-invasive imaging at the University of Jena, Germany. Her specific interest was the effect of cryopreservation, decellularization/recellularization and biomechanical forces on heart valve extracellular matrix (ECM) structures and cells. She helped develop the use of multiphoton laser-based confocal microscopy and second harmonic generation as non-invasive tissue imaging tools. For her post-doctoral work, she focused on cardiac stem cell biology and biomaterials. Here, her seminal work was to be the first scientist to demonstrate that induced pluripotent stem cells (iPSCs) differentiate towards the cardiovascular and hematopoietic lineages, showing that beating cardiomyocytes could be derived from iPSCs. She then returned to Germany to join the Fraunhofer IGB in Stuttgart, Germany as a group leader, which was then followed by her appointment as Professor in the Medical Faculty of the University of Tübingen, and promotion to Department Head and later Director of the Fraunhofer IGB. She remained focused on cardiovascular development and biomaterials, and moved into the areas of in vitro test systems and Raman microspectroscopy, with a focus on ECM proteins.
Awards
Best Young Researcher Award/ Family Klee Prize, German Society for Biomedical Engineering
Young Investigator Morphological Sciences Award, American Association of Anatomists
Academia.net top female scientists in Germany
Tissue Engineering and Regenerative Medicine International Society (TERMIS)-EU Young Investigator Award
CyberOne Business Plan Competition Finalist
RPB Harold F. Spalter International Scholar Award
Germany's Top 100 Innovators
German Stem Cell Network GSCN 2021 Hilde Mangold Award
Research focus
Currently, her research lab at the University Tübingen focuses on the translation of human development into clinically relevant biomaterials and regenerative therapies, and the development of diagnostic tools to assess (stem) cell states, discover therapeutic candidates and diagnose diseases. She leverages her appointments to bridge the gaps between science and industry to drive viable health care solutions, particularly at the NMI where they focus on supporting local SMEs
Editorial work
Katja Schenke-Layland is currently the Co-Editor-In-Chief of Tissue Engineering Part B (Mary Ann Liebert) and Executive Editor of Advanced Drug Delivery Reviews (Elsevier), as well as on the editorial boards of Matrix Biology (journal) (Elsevier), Current Opinion in Biomedical Engineering (Elsevier), Journal of 3D Printing in Medicine (Future Medicine) and Scientific Reports (Nature Research). She is a fellow/ board member of the German National Academy of Science and Engineering, German Central Ethics Committee for Stem Cell Research, International and German Societies of Matrix Biology and the European Alliance for Medical and Biological Engineering and Science.
References
1977 births
Living people
Stem cell researchers
Cardiovascular researchers
Biomedical engineers
University of Jena alumni | Katja Schenke-Layland | [
"Biology"
] | 745 | [
"Stem cell researchers",
"Stem cell research"
] |
66,796,710 | https://en.wikipedia.org/wiki/Symposium%20on%20Experimental%20Algorithms | The International Symposium on Experimental Algorithms (SEA), previously known as Workshop on Experimental Algorithms (WEA), is a computer science conference in the area of algorithm engineering.
Notes
Computer science conferences | Symposium on Experimental Algorithms | [
"Mathematics",
"Technology"
] | 40 | [
"Algorithms",
"Mathematical logic",
"Computer science conferences",
"Applied mathematics",
"Computer science"
] |
66,797,211 | https://en.wikipedia.org/wiki/Blondel%27s%20experiments | Blondel's experiments are a series of experiments performed by physicist André Blondel in 1914 in order to determine what was the most general law of electromagnetic induction. In fact, noted Blondel, "Significant discussions have been raised repeatedly on the question of what is the most general law of induction: we should consider the electromotive force (e.m.f.) as the product of any variation of magnetic flux () surrounding a conductor or of the fact that the conductor sweeps part of this flux?".
In the first case Blondel referred to Faraday-Neumann law, which is often considered the most general law, while in the second case he referred to Lorentz force.
Normally experiments to verify the first case consist of measuring the induced current in a closed conducting circuit, concatenated to the magnetic induction field of a magnet, with varying in time, while for the verification of the second case usually we measure the induced current in a closed circuit of variable shape or moving by cutting perpendicularly a field constant.
The second case, however, is due to a variation of the magnetic flux , not so much because the intensity of varies, but because the surface crossed by the field varies.
Blondel, on the other hand, devised "a new device which consists in varying the total magnetic flux passing through a coil, by a continuous variation of the number of turns of this coil". In this way and are constant for each coil, but the total flux varies with the number of coils affected by the field .
It follows that, given the flux concatenated to a single loop and the total number of loops, by Faraday-Neumann's law, the resulting electromotive force is:
i.e. dependent on the variation of the number of turns in time.
Blondel tested four configurations of his apparatus in which he demonstrates that a change in flux does not always generate an e.m.f. in a circuit concatenated to it, concluding that the Faraday-Neumann law cannot be the general law.
Apparatus description
The apparatus consists of an electromagnet E, whose U-shaped core terminates in two large parallel plates P and P' . Two induction coils B generate the magnetic field in E. Between the two plates there is a rotating wooden drum T on which an insulated electric wire is wound. The wire exits from the center of the drum and connects with a ring b integral with the drum and of negligible diameter with respect to the drum itself. A sliding contact f electrically connects the wire to a galvanometer G, by means of a resistor R so that current can flow even when the drum is rotating.
To the galvanometer is connected, in a specular way to the first, another drum T' which is connected to a motor M, able to rotate the drum T' at adjustable speed.
Finally, the electric wire passing through the center of both drums, after a certain number of windings around one of them, reaches the other drum, closing the circuit. When motor M starts up, it can increase the number of coils wrapped around T' by decreasing those around T or vice versa.
Blondel connects the wire through f to the wire wound on T in four different ways, making equally distinct experiments.
The four experiments
First experiment
The wire wound on T is connected directly to the rotation shaft on which rests the sliding contact f, through the conducting ring b, of negligible diameter, as shown in the figure.
Connecting the drum T' to the motor M it quickly reaches a constant speed and so does the other drum T. Maintaining this speed for about a minute, the galvanometer needle moves, indicating the presence of an electromotive force (e.m.f.).
Second experiment
The wire wound on T is connected to a conducting ring of diameter equal to that of the drum T and integral with it. The contact f runs along the edge of the ring which turns with the drum.
So compared to the previous experiment f, instead of being connected with the center of the coil is connected at a point as far from the center as the radius of the coil itself.
In this case the galvanometer shows that e.m.f. induced during drum rotation is zero, unlike what could be expected having in mind Faraday's original experiment.
Since Blondel feared that it could be objected that the result is due to the fact that, during rotation, the circuit between f and the point of attachment of the coil wire to the ring may follow two different paths that partially neutralize each other, he makes a third experiment.
Third experiment
The wire wound on T is connected, by means of a sliding contact coming out from the edge of the drum, to the edge of a solid conducting disk, having a diameter equal to that of the drum T and parallel to it but detached, so as to remain stationary while the drum turns. The contact f rests directly on the central part of the disk.
Also in this case the e.m.f. measured by the galvanometer is zero.
From the last two results Blondel concludes that the e.m.f. measured in the first experiment was not caused by the progressive decrease of the flux but by the sweeping of the flux by the wire joining the center of the coil with the brush f.
To further confirm this he performs a fourth experiment.
Fourth experiment
The wire wound on T is connected to the edge of a solid disk of diameter equal to that of the drum T and integral with it. The contact f strips against the center of the disk.
In this case the galvanometer records a e.m.f. exactly equal to that of the first experiment. Not only that, but if you rotate the disc keeping the drums still, it still records the same e.m.f. that is caused only by the fact that a part of the circuit sweeps the flow. Moreover, by varying the point of contact of the coil from the outer edge to the center of the disc, the induced e.m.f. is proportional to the area of the circle having as radius the distance between the two points of attachment.
The result is analogous to the Faraday disk.
Conclusions
From here Blondel deduces that:
1) When the magnetic field is constant, there is an e.m.f. only if the circuit cuts through the lines of force of the field, as in the first experiment (rotational axis-drum edge section). If this does not happen, even varying the total flux through the circuit, there is no e.m.f., as in the second experiment.
2) The case in which the closing line of the circuit (axis-edge section) moves within a solid conductor (but the conductor remains stationary), as in the third experiment, is not equivalent to the case in which the entire conductor moves, as in the fourth experiment (in this case the Lorentz force acts).
Thus "one must reject as inaccurate the too general statements of the law of induction" and to the statement that "An electromotive force originates in a closed circuit when the number of magnetic lines passing through it varies...." should be added "and when the variation is produced either by the conductor sweeping the lines of force or by a variation in the field of the inductor itself".
Basically experiments show how Faraday's basic law, that is the one that takes into account only flux variation, cannot be the general law of induction. In fact it is necessary to include also the contribution due to Lorentz force to obtain the general formula.
See also
Carl Hering
Maxwell–Lodge effect
Riccardo Felici
References
Further reading
Physics experiments
Electrodynamics | Blondel's experiments | [
"Physics",
"Mathematics"
] | 1,572 | [
"Electrodynamics",
"Experimental physics",
"Physics experiments",
"Dynamical systems"
] |
66,800,271 | https://en.wikipedia.org/wiki/LHS%201815%20b | LHS 1815 b (also TOI-704 b) is a thick disk exoplanet, discovered in 2020 by TESS. The planet is located outside the galactic plane.
Characteristics
LHS 1815 b is a terrestrial planet (super-Earth) with a mass of 0.0132 and a radius of 0.09707 and was discovered by TESS in 2020. The planet is the first discovered example of a "thick-disk planet" located within a thick disk, one of the galactic structures much higher, than the positions of other planetary systems discovered by TESS.
Orbit
The orbital period is 3.81433 days and the semimajor axis is 0.0404 au.
Other designations
LHS 1815 b is also known as TOI-704 b and TIC 260004324 b.
References
Exoplanets discovered in 2020
Pictor
Exoplanets discovered by TESS | LHS 1815 b | [
"Astronomy"
] | 186 | [
"Pictor",
"Constellations"
] |
66,800,695 | https://en.wikipedia.org/wiki/NGTS-1 | NGTS-1, also designated as TOI-551 is a solitary star located in the southern constellation Columba, the dove. With an apparent magnitude of 15.52, NGTS-1 can only be seen through a powerful telescope. Gaia DR3 parallax measurements imply a distance of 710 light-years and it is drifting away rapidly with a heliocentric radial velocity of .
Properties
NGTS-1 has a stellar classification of M0.5, indicating that is an early M-type star. It has 61% of the mass of the Sun and over half of its radius. Since red dwarfs are fully convective, they do not burn as much as more massive stars. As a result, NGTS-1 only radiates 7.02% of the luminosity of the Sun from its photosphere at an effective temperature of . There was difficulty determining the metallicity of the object due to its faintness, but NGTS-1 is assumed to be around solar metallicity. In addition, this also provided some uncertainty about the star's properties since red dwarfs properties are dependent on their metallicity. It spins too slowly for it to be measured accurately, having a projected rotational velocity lower than .
Planetary system
The discovery of a hot Jupiter orbiting the star was reported in 2017 as part of the Next Generation Transit Survey. The media also dubbed NGTS-1b as "monstrous" since the planet is relatively large compared to its host star.
References
Columba (constellation)
M-type main-sequence stars
Planetary systems with one confirmed planet | NGTS-1 | [
"Astronomy"
] | 323 | [
"Columba (constellation)",
"Constellations"
] |
66,800,872 | https://en.wikipedia.org/wiki/Teruaki%20Mukaiyama | was a Japanese organic chemist. One of the most prolific chemists of the 20th century in the field of organic synthesis, Mukaiyama helped establish the field of organic chemistry in Japan after World War II.
Education
Mukaiyama studied chemistry at the Tokyo Institute of Technology, earning his BSc in synthetic organic chemistry in 1948. He became assistant professor at Gakushuin University in 1953, where he stayed until he received his Ph.D. in synthetic organic chemistry from the University of Tokyo in 1957.
Research and career
Early work
Mukaiyama became an assistant professor at the Tokyo Institute of Technology in 1958 and earned his full professorship in 1963. During this time, his main focus was on organophosphorus chemistry. While examining deoxygenation reactions involving phosphines, Mukaiyama found that the mercury(II) acetate employed as a catalyst would react with phosphorus(III) compounds to produce acetic anhydride. This initial example expanded into the concept of the redox condensation reaction, in which a weak acid and weak base catalyze a condensation by means of a redox reaction – this would become a primary research focus for Mukaiyama for much of his career. In the original reaction, the phosphine served as the reducing agent by accepting oxygen, while the mercury(II) was the oxidation agent that accepted hydrogens, resulting in the condensation of carboxylic acids with the loss of a molecule of water.
This framework was expanded to include the formation of a variety of other functional groups, including esters and amides, but the most significant was the synthesis of phosphoric esters using DEAD and an alcohol in 1967. The same year that paper was published, Mukaiyama's co-author and former student Oyo Mitsunobu attacked the products of the reaction with a carboxylic acid in the presence of triphenylphosphine to yield an ester, creating what is now known as the Mitsunobu reaction.
Modifications to the aldol reaction
The aldol reaction is an essential tool for synthetic chemists. At its simplest, the aldol reaction involves two carbonyl compounds which join, forming a carbon-carbon bond. Depending on whether it is performed in acidic or basic conditions, the reaction proceeds by one of the carbonyls attacking the other, which has tautomerized into either an enol or enolate. However, when both carbonyls are similar in pKa they may both function as either the nucleophile or the electrophile, meaning the reaction may form either cross-products or self-products.
While investigating sulfur-boron compounds in 1971, Mukaiyama reported that the reaction of ketene with thioboronite produced a beta-hydroxyalkanethioate via a vinyloxyborane intermediate that would perform an aldol reaction with formaldehyde leftover from the synthesis of ketene. These vinyloxyboranes proved straightforward to synthesize directly from the desired ketones using DBBT, which has a more electron-withdrawing triflate group in place of the sulfur. Boron enolates provide an alternative to metal enolates for performing cross-aldol reactions.
As an extension of his earlier research with trivalent phosphorus as an oxygen acceptor, Mukaiyama began to examine the role of metallic catalysts for the dehydrative Friedel-Crafts alkylation and in particular titanium(IV) tetrachloride. In 1973, he reported that titanium(IV) chloride treated with zinc powder catalyzed a pinacol coupling of carbonyls in THF which formed an alkene after reflux with 1,4-dioxane. This is what is now known as the McMurry reaction - McMurry published a year later and cited both Mukaiyama and the group of Tyrlik in Poland in his paper, but Japan's position in the international organic chemistry community was not yet fully developed and the naming persists.
Mukaiyama again turned to titanium(IV) chloride while seeking an appropriate Lewis acid to activate aldehydes for reaction with silyl enol ethers in what became known as the Mukaiyama aldol reaction. Published in 1973 as Mukaiyama was in the process of migrating to the University of Tokyo, it is a cross-aldol reaction between a silyl enol ether (typically derived from a carbonyl of choice using the method of Stork) and an aldehyde of choice in the presence of a Lewis acid like titanium(IV) chloride. The reaction is a landmark case on how activating aldehydes can allow even electronically neutral and weakly nucleophilic compounds like silyl enol ethers to be used as reagents.
A Lewis acid must be added to use silyl enol ethers but not boron enolates because boron has an empty orbital but silicon does not, allowing boron to act as an electron acceptor. Tin(II) goes a step further by having multiple empty orbitals, allowing it to coordinate chiral ligands and induce enantioselectivity. In 1982 Mukaiyama showed that tin(II) enolates formed from tin(II) triflate could produce aldol products that were over 95% stereospecific. In a time when asymmetric reactions largely relied on chiral auxiliaries to be covalently bound to the reactants, tin(II) enolates formed from chiral diamine ligands derived from L-proline could achieve over 90% ee.
Namesake reagent
In 1975, Mukaiyama reported that N-methyl-2-chloropyridinium iodide (also called 2-chloro-1-methylpyridinium iodide) allowed for a dehydration condensation between a carboxylic acid and an alcohol or similar functional groups to form an ester linkage. In the initial stage of the process, the carboxyl displaces the halogen atom on the reagent in the presence of a base. The resulting pyridyl ester is an activated electrophile and also serves as a good leaving group in a subsequent nucleophilic acyl substitution reaction with the alcohol reactant as nucleophile. Thus, the family of 2-halo-N-alkylpyridinium salts are named the Mukaiyama reagents. The reaction gives low yields if there are sterically large groups adjacent to the site of the reaction, such as tertiary carbons, but can be improved by using bromine as the halogen. In the years since its discovery, a number of different onium salts of aza-arenes have been used to catalyze a number of different dehydration reactions, including a macrolactonization. In 1994, Isamu Shiina developed his namesake macrolactonization in the Mukaiyama lab, making use of an aromatic carboxylic acid anhydride in the presence of a Lewis acid catalyst.
Taxol synthesis
In the early 1990s, at least thirty separate groups were working on the total synthesis of the chemotherapy medicine paclitaxel (Taxol), culminating with the groups of Robert A. Holton and K. C. Nicolaou publishing nearly simultaneously in 1994. By then, Mukaiyama had retired from the University of Tokyo after reaching the mandatory age of 60 and set up an academic lab at the Tokyo University of Science. The Mukaiyama taxol total synthesis was published between the years of 1997 and 1999 after five years of research, making the Mukaiyama lab the sixth group to report results.
This total synthesis is largely a linear synthesis which forms the four rings of taxol in the order C, B, A, D. It is differentiated from the others from its use of L-serine as a starting material and for being the only total synthesis not to use the Ojima lactam to create the amide tail. Instead, the tail is created from scratch by converting benzyloxyacetic acid into a silyl enol ether, joining it with benzaldehyde with a Mukaiyama aldol addition, and creating the amide from the alcohol via a Mitsunobu reaction followed by benzoylation.
The synthesis also made use of three Swern oxidations during the synthesis of the C ring. This reaction is typically performed at very low temperatures (< -50 °C) to stabilize its activated DMSO intermediate and constantly evolves the strong-smelling DMS, making it very difficult to work with at large scales. The difficulties encountered during their total synthesis prompted Mukaiyama to pursue an alternative method, and in 2001 a room-temperature oxidation involving N-chlorosuccinimide and a catalytic amount of N-t-butylbenzenesulfenamide was developed. The more electronegative nitrogen adjacent to the sulfur in the sulfenamide increased the stability of the intermediate relative to that formed from the sulfur-carbon bond of DMSO and was inspired by his earlier work with sulfenamides while still at the Tokyo Institute of Technology.
Legacy
Mukaiyama had a scientific career spanning over sixty years, during which he published over 900 papers. After its founding in 1972, Mukaiyama only published in the Japanese journal Chemistry Letters, citing a belief that "the results of one's chemistry should be published in journals of one's country." The combination of the high quality of his work and the over 600 papers that he published in Chemistry Letters played an important role in its spread to other nations.
A total of 145 people earned their doctorates under Mukaiyama, with 54 eventually becoming professors in various institutions.
Honors and awards
Mukaiyama has been recognized for his achievements in the form of seven honorary degrees and membership in the national academies of four nations. He is the namesake of the Mukaiyama Award, awarded by the Society of Synthetic Organic Chemistry, Japan since 2005. His major awards include:
Chemical Society of Japan Award in 1973
Imperial Prize and Academy Prize from the Japan Academy in 1983
Nicholaus Copernicus Medal from the Polish Academy of Sciences in 1986
Person of Cultural Merit from Japan in 1992
Chevalier de l’Ordre National du Mérite from France in 1994
ACS Award for Creative work in Synthetic Organic Chemistry from the American Chemical Society in 1996
Order of Culture from Japan in 1997
Tetrahedron Prize for Creativity in Organic Chemistry from Elsevier in 1998
Sir Derek Barton Gold Medal from the Royal Society of Chemistry in 1998
References
1927 births
2018 deaths
People from Nagano (city)
Tokyo Institute of Technology alumni
University of Tokyo alumni
Academic staff of Tokyo Institute of Technology
Japanese organic chemists
20th-century Japanese chemists
21st-century Japanese chemists | Teruaki Mukaiyama | [
"Chemistry"
] | 2,229 | [
"Organic chemists",
"Japanese organic chemists"
] |
66,804,473 | https://en.wikipedia.org/wiki/ROXs%2012 | ROXs 12 is a binary system of pre-main-sequence stars. It belongs to the Rho Ophiuchi cloud complex. The surface temperature of the primary star is 3900 K. ROXs 12 is much younger than the Sun with an age of 7.6 million years.
A multiplicity survey detected a stellar companion to ROXs 12 in 2017, named 2MASS J16262774–2527247, at a projected separation of 5100 AU.
Planetary system
In 2005, one planet was discovered on a wide orbit by direct imaging, was confirmed in 2013 and named ROXs 12 b. The planet's measured temperature is 3100 K. The spectroscopy of the planet was obtained with Keck and Gemini, revealing a low surface gravity and a spectral type of L0 ±2, making this object either a late M-dwarf or an early L-dwarf. The signs of low gravity includes weak alkali absorption and a triangular H-band spectrum shape. The study also found misalignment between the line-of-sight inclinations of ROXs 12A and 2MASS J16262774–2527247. ROXs 12 B is also likely misaligned with its host star. This was interpreted as either formation similar to fragmenting binary stars or ROXs 12B formed in an equatorial disk that was torqued by 2MASS J16262774–2527247. This study also found strong signs of accretion around 2MASS J16262774–2527247 from emission lines, including strong H-alpha emission.
The primary star is surrounded by a protoplanetary disk, although it is not very massive, being less than 4 . The secondary star also has a protoplanetary disk, and it is much more massive, equal to 10-1.07. The disk is inclined to the equatorial plane of the star.
References
Scorpius
Pre-main-sequence stars
Planetary systems with one confirmed planet
J16262803-2526477
Circumstellar disks
Binary stars | ROXs 12 | [
"Astronomy"
] | 438 | [
"Scorpius",
"Constellations"
] |
66,805,270 | https://en.wikipedia.org/wiki/Engineered%20cellular%20magmatic | Engineered cellular magmatics (ECMs) are synthetic stone of glass and ceramic. ECMs replicate rare, naturally occurring volcanic materials, and exhibit useful structural and chemical properties of those materials. The US Department of Energy has recognized ECMs as an advanced material, funding further research into the manufacture and application of ECMs through ARPA-E and Savannah River National Laboratory.
Properties
ECMs can be engineered to include a broad range of silicate species, with various reactivity. Their physical structure can range from closed to open cell, resembling pumice or porous ceramic. They can be composed of internal pore and vesicular structures with individual cross sections that can measure from millimeter down to nanometer scale. Open cell varieties exhibit extensive surface areas which amplify ion exchange capabilities (both cationic and anionic). These features make them well suited for various cement construction filtration and remediation applications. They typically contain both amorphous and crystalline structures.
Application
Known uses for ECMs include air and water filtration, biological and chemical remediation, microbial habitat, soil and cementitious amendments. They can also be used in the manufacture of various forms of zeolite due to the resulting silicate lattice, and in various reactors for chemical separation. They meet and exceed the ASTM Standard Specification for Lightweight Aggregates for Structural Concrete, and exceed ASTM standards for vegetative green roof media.
History
ECMs share a history with foam glass, but are engineered for specific chemical reactivity and structural properties not generally considered the domain of foam glass. The term engineered cellular magmatic was adopted to describe the material in late 2019 by inventor Robert Hust. Other named inventors include Gene Ramsey, Cory Trivelpiece, Gert Nielsen, and Philip Galland.
Manufacture
ECMs can be manufactured from raw materials (minerals with high silica content) and a range of waste and recycled materials that, by their utilization, represent significant savings in both energy and carbon emissions. ECMs have been successfully created utilizing various waste streams, upcycling glass waste, municipal incinerator waste ash, carbon fiber waste, and wastes from various types of mining. The production process is similar to that of sintered foam glass or ceramics, consisting of 1) grinding the input materials to a powder, 2) firing the material at various levels of thermal exposure (500º - 2000 °C) as it 3) travels through a 36-meter (120 ft.) long furnace.
See also
Silicate
Ceramic foam
Foam glass
High Performance Concrete
Materials science
Environmental technology
Upcycling
References
Materials science | Engineered cellular magmatic | [
"Physics",
"Materials_science",
"Engineering"
] | 533 | [
"Applied and interdisciplinary physics",
"Materials science",
"nan"
] |
66,807,070 | https://en.wikipedia.org/wiki/Cotadutide | Cotadutide is an experimental drug for the treatment of type 2 diabetes mellitus. It lowers blood glucose levels by mimicking the human hormones glucagon-like peptide 1 and glucagon, which play a role in blood sugar regulation. The drug is a peptide that is injected under the skin.
Cotadutide is in Phase II clinical trials . Cotadutide, a therapeutic agent, was undergoing Phase II clinical trials. This stage of trials typically involves evaluating the drug's effectiveness and further assessing its safety in a larger group of participants, compared to earlier phases.
See also
Glucagon (medication)
References
GLP-1 receptor agonists
Experimental diabetes drugs
Peptide therapeutics
Peptides | Cotadutide | [
"Chemistry"
] | 149 | [
"Biomolecules by chemical classification",
"Peptides",
"Molecular biology"
] |
66,807,151 | https://en.wikipedia.org/wiki/Nitryl%20chloride | Nitryl chloride is a volatile inorganic compound with formula ClNO2. At standard conditions it is a gas.
Formation
Nitryl chloride can be formed in the reaction of dinitrogen pentoxide with chlorides or hydrogen chloride:
N2O5 + 2HCl → 2ClNO2 + H2O
N2O5 + NaCl → ClNO2 + NaNO3
Reactions
Nitryl chloride adds to olefins in a radical reaction.
References
Nitro compounds
Nitrogen oxohalides
Nitrogen(V) compounds
Oxychlorides
Inorganic chlorine compounds | Nitryl chloride | [
"Chemistry"
] | 119 | [
"Inorganic chlorine compounds",
"Inorganic compounds"
] |
66,807,167 | https://en.wikipedia.org/wiki/HD%20110113 | HD 110113, also known as TOI-755, is a star with a pair of orbiting exoplanets in the Centaurus constellation. With an apparent visual magnitude of 10.063, it is much too faint to be viewed with the naked eye. The system is located at a distance from the Solar System of about . It is drifting further away with a heliocentric radial velocity of 17 km/s. A planetary system was discovered orbiting this star in 2021.
The spectrum of HD 110113 presents as a G-type main-sequence star, or yellow dwarf, with a stellar classification of G8V. It has an estimated age of four billion years and is spinning slowly with a rotation period of 20.8 days. The star is considered a solar analog, having nearly the same mass and size as the Sun. It radiating 91% of the Sun's luminosity from its photosphere at an effective temperature of 5,732 K. The star displays rotationally-modulated variability that is indicative of star spots.
Planetary system
The two candidate planets orbiting TOI-755 – TOI-755b and TOI-755c – were announced in 2021. TOI-755b's temperature is over and TOI-755c's temperature is cooler at around , which means they are Hot Neptunes.
References
G-type main-sequence stars
Planetary systems with two confirmed planets
Centaurus
Durchmusterung objects
110113
061820
0755 | HD 110113 | [
"Astronomy"
] | 314 | [
"Centaurus",
"Constellations"
] |
66,807,765 | https://en.wikipedia.org/wiki/Sydney%20Leach | Sydney Leach FRS (11 April 1924—24 December 2019) was a British scientist based in France whose research areas included the fields of spectroscopy, photophysics and photochemistry. His work studying molecular ions led to new areas of interest, including planetary and atmospheric science, as well as the newly developing field of astrobiology.
His scientific career was based in Paris, including his founding Directorship at Laboratoire de Photophysique Moléculaire Orsay, and his later move to L'Observatoire de Meudon where he was based for the remainder of his career.
Leach was elected Fellow of the Royal Society in 1993.
References
British physicists
Fellows of the Royal Society
1924 births
2019 deaths
Spectroscopists
Fellows of the American Physical Society | Sydney Leach | [
"Physics",
"Chemistry"
] | 155 | [
"Physical chemists",
"Spectrum (physical sciences)",
"Analytical chemists",
"Spectroscopists",
"Spectroscopy"
] |
66,810,834 | https://en.wikipedia.org/wiki/Extended%20natural%20numbers | In mathematics, the extended natural numbers is a set which contains the values and (infinity). That is, it is the result of adding a maximum element to the natural numbers. Addition and multiplication work as normal for finite values, and are extended by the rules (), and for .
With addition and multiplication, is a semiring but not a ring, as lacks an additive inverse. The set can be denoted by , or . It is a subset of the extended real number line, which extends the real numbers by adding and .
Applications
In graph theory, the extended natural numbers are used to define distances in graphs, with being the distance between two unconnected vertices. They can be used to show the extension of some results, such as the max-flow min-cut theorem, to infinite graphs.
In topology, the topos of right actions on the extended natural numbers is a category PRO of projection algebras.
In constructive mathematics, the extended natural numbers are a one-point compactification of the natural numbers, yielding the set of non-increasing binary sequences i.e. such that . The sequence represents , while the sequence represents . It is a retract of and the claim that implies the limited principle of omniscience.
Notes
References
Further reading
External links
Number theory | Extended natural numbers | [
"Mathematics"
] | 260 | [
"Discrete mathematics",
"Number theory"
] |
66,810,877 | https://en.wikipedia.org/wiki/Emily%20S.%20C.%20Ching | Emily Shuk Chi Ching () is a Hong Kong theoretical physicist based at the Chinese University of Hong Kong. She researches fluid turbulence and has been elected as a fellow of the Institute of Physics and American Physical Society.
Education
Emily Shuk Chi Ching attended the University of Hong Kong for her bachelor's degree and the Chinese University of Hong Kong for her master's degree. She graduated from the University of Chicago with a PhD in physics in 1992. She then completed a post-doctoral research appointment at the Kavli Institute for Theoretical Physics, which is part of the University of California, Santa Barbara.
Career
After finishing her post-doc, Ching returned to Hong Kong, accepting a position at the Chinese University of Hong Kong in 1995. Her research interests include scaling and structures as they relate to fluid turbulence, polymers in turbulence, boundary layers in Rayleigh–Bénard convection, and network reconstruction from dynamics.
She has been involved as an associate editor or editorial board member for several journals, including Physical Review E, Annual Review of Condensed Matter Physics, and Journal of Turbulence.
Awards and honours
In 1999 she received the Achievement in Asia Award from the Overseas Chinese Physics Association. Ching was elected as a fellow of the Institute of Physics in 2004 and the American Physical Society in 2005.
Personal life
She speaks Cantonese and English.
References
Living people
Alumni of the University of Hong Kong
University of Chicago alumni
Hong Kong physicists
Chinese women physicists
Theoretical physicists
Fellows of the American Physical Society
Fellows of the Institute of Physics
Year of birth missing (living people)
Alumni of the Chinese University of Hong Kong | Emily S. C. Ching | [
"Physics"
] | 318 | [
"Theoretical physics",
"Theoretical physicists"
] |
66,811,463 | https://en.wikipedia.org/wiki/Crescent%20Farm | The Crescent Farm, near Canton, Georgia on Georgia State Route 5 southeast of Georgia State Route 140, is a historic property that was listed on the National Register of Historic Places in 1989. The listing includes two contributing buildings (the house and the barn/stable) and a non-contributing structure, on .
Description
The farm's two-story Georgian Revival house, built in 1922 and known as Edgewater Hall or A.L. Coggins House, is situated on Mt. Etowah and overlooks the Etowah River, which forms a crescent shape around the original property. The house was designed by Atlanta architect Francis P. Smith (1886–1971). The house was renovated considerably in 1986 when it was converted for use by the Cherokee Federal Savings Bank.
Separated from the house by Georgia State Route 5 is the associated rock and brick barn, built in 1906 as a stable for race horses. The barn was built after a fire destroyed its wooden predecessor, killing valuable race horses. The barn was built from rock quarried by the Etowah River, and with bricks in its gable level; it has a stepped gable at the front. The property also had a one-mile track used for harness racing. Crescent Farm was known for its racehorses raised by A.L. Coggins. Abbedale (1917–1950) was the farm's most famous racehorse, and went on to sire six pacers with two-minute mile records.
References
External links
rockbarn.org
Georgia History
National Register of Historic Places in Cherokee County, Georgia
Buildings and structures completed in 1906
Stepped gables
Farms on the National Register of Historic Places in Georgia (U.S. state)
Horse farms in the United States
Georgian Revival architecture in Georgia (U.S. state) | Crescent Farm | [
"Engineering"
] | 362 | [
"Stepped gables",
"Architecture"
] |
66,811,571 | https://en.wikipedia.org/wiki/Long%C3%A8re | A longère is a type of longhouse typical of the regions of Brittany and Normandy in northwestern France. It is a long, narrow dwelling, developing along the axis of its peak, typically inhabited by farmers and artisans.
Longère also means a "long wall" or "gutter wall" of a building, whether for a church or house, in Lower Brittany.
See also
Quistinic
Manoir de Mézarnou
Moulin d'Olivet
References
House types
Buildings and structures in Normandy
Buildings and structures in Brittany | Longère | [
"Engineering"
] | 107 | [
"Architecture stubs",
"Architecture"
] |
66,812,531 | https://en.wikipedia.org/wiki/The%20Hidden%20City%20%28film%29 | The Hidden City () is a 2018 documentary film directed by Víctor Moreno. The film explores the underground infrastructure beneath Madrid, Spain, including sewers, pipes, train tunnels, and man-made corridors, with appearances by maintenance workers, animals, and commuters.
An international co-production between Spain, Germany and France, The Hidden City premiered at the Seville European Film Festival in November 2018.
Synopsis
The Hidden City consists primarily of footage of subterranean structures and systems beneath Madrid, Spain, both filmed by director of photography José Ángel Alayón and by surveillance cameras. Elements presented include train tracks and tunnels; sewer pipes and dripping brick walls; underground workers; animals—such as an owl, cockroaches, rats, and feral cats; human commuters travelling by metro; and microscopic views of microorganisms in sewage water. The film features no dialogue aside from occasional commands received by portable communicators.
Production
In a 2019 interview with Variety, Víctor Moreno stated: "There were three particularly significant difficulties [with filming underground]. The first was obtaining permits that were delayed for about a year as they involved many institutions. The second was the long process of searching for locations since it was a very large space, of which there are hardly any references, and which is as big as the above-ground city. And the third was the filming itself, because it involved shooting in spaces with very difficult access, with heavy equipment and little or no mobility."
Reception
On Rotten Tomatoes, the film has a score of based on reviews, with an average rating of .
Javier Ocaña of El País praised the film for its "formidable photographic and sound work", and wrote that "Víctor Moreno has created an unusual and identifiable style, of extreme solidity and beauty". Cinemanías Carlos Marañón gave the film a score of four-and-a-half out of five stars, calling it "an underground space odyssey".
Jonathan Holland, writing for The Hollywood Reporter, commended the film's audio as "extraordinary, a detailed and carefully worked symphony of engineering noises", and called the film as a whole "a mood piece that's as much an experience as a movie — [which] has the rare and impressive virtue of slightly rearranging our perspective as we emerge afterwards, blinking." Varietys Jamie Lang wrote that "Moreno goes deep into the unseen tunnels, metros and sewers that support life for the millions above, juxtaposing that world with the one seen every day. Lack of light or color, otherworldly sounds and machinery and nocturnal animals inhabit the dark corridors in a cinematic experience that begs to be enjoyed in a pitch-black theater with high-quality speakers."
References
External links
2018 documentary films
2018 films
Films shot in Spain
Sewerage infrastructure
Subterranea (geography) | The Hidden City (film) | [
"Chemistry"
] | 573 | [
"Water treatment",
"Sewerage infrastructure"
] |
66,812,671 | https://en.wikipedia.org/wiki/Iota%20Mensae | Iota Mensae is a single star about away in the faint constellation Mensa. It has a very slightly variable apparent magnitude of 6.0, making it visible with the naked eye under good skies.
Iota Mensae has a spectral type of B8III, indicating that it has exhausted hydrogen at its core and expanded away from the main sequence. It is about 3.6 times the mass (), 301 times as luminous, and has swollen to 9.5 times the radius of the Sun (). It is calculated to be 314 million years old.
It has been catalogued as a chemically peculiar star with abnormally strong lines of silicon in its spectrum but this classification is now considered doubtful. Its brightness varies by a few hundredths of a magnitude. Its period was initially measured at 2.6 days, but this is now considered to be a period of 5.3 days with primary and secondary minima of a similar depth. The variability is thought to be due to the rotation of the star.
References
Mensa (constellation)
Iota, Epsilon
026264
1991
038602
B-type giants
Rotating ellipsoidal variables
Durchmusterung objects | Iota Mensae | [
"Astronomy"
] | 244 | [
"Mensa (constellation)",
"Constellations"
] |
78,397,671 | https://en.wikipedia.org/wiki/Ainuovirine | Ainuovirine is a non-nucleoside reverse transcriptase inhibitor (NNRTI) being developed by Kainos Medicine for the treatment of HIV infections. Ainuovirine was approved in China in 2021 for the treatment of HIV-1 infection.
References
Alkylbenzenes
Isopropyl compounds
Benzonitriles
Ketones
Pyrimidinediones | Ainuovirine | [
"Chemistry"
] | 79 | [
"Pharmacology",
"Ketones",
"Functional groups",
"Medicinal chemistry stubs",
"Pharmacology stubs"
] |
78,399,080 | https://en.wikipedia.org/wiki/Las%20Cabezas%20de%20San%20Juan%20%28Puerto%20Rico%29 | Las Cabezas de San Juan (Spanish for 'the San Juan capes' or 'headlands'), officially Cabo San Juan (Cape San Juan in English), is a coastal area and nature reserve located in the northeastern corner of the main island of Puerto Rico, particularly in the Cabezas barrio of the municipality of Fajardo. The reserve is famous for its biodiversity, with its bioluminescent lagoon (Laguna Grande, one of the three year-round bioluminescent bodies of water in the territory and one of seven in the Caribbean), its coral reefs, and its subtropical dry and mangrove forests, and for its history, particularly for its lighthouse and its role during the Puerto Rico campaign of the Spanish–American War.
Geography
Cabezas de San Juan Nature Reserve consists mainly of a large peninsula located in the north-westernmost corner of Puerto Rico and its surrounding bodies of water. The reserve is connected to the west to Seven Seas State Park (Parque Nacional Seven Seas) and the Northeast Ecological Corridor, and by sea in the east to La Cordillera Reef Nature Reserve, a large protected marine area consisting of a small chain of cays, reefs, and islets, collectively known as La Cordillera (''the mountain range'') or Cayos de la Cordillera (Cordillera Cays). To the north it is bound by the Atlantic Ocean and in the south it borders the fishing community of Las Croabas.
Toponymy
Las Cabezas de San Juan obtains its name from the rocky headlands found at the northernmost point of a peninsula located in the northwestern-most point of the main island of Puerto Rico, which formerly known as San Juan Bautista until early in the 18th century. While the name for the island (San Juan Bautista) and its capital city (Ciudad de Puerto Rico) were officially exchanged by 1746, the name "Cabezas de San Juan" rather than "Cabezas de Puerto Rico" kept being used to the describe this extremity of the island despite the change of name of the island colloquially and in official documents.
Ecology
Bioluminescence
Laguna Grande (Spanish for 'big lagoon'), located within the nature reserve, is one of the three bodies of water in Puerto Rico with year-round bioluminescence, and one of seven in the Caribbean. The other three bioluminescent bodies of water in Puerto Rico are Puerto Mosquito in Vieques and Bahía Fosforescente at La Parguera Nature Reserve in Lajas.
History
The area of Las Cabezas de San Juan was inhabited by the indigenous Taino people at the time of the Spanish arrival to the Americas in 1492. Archaeological findings in the area suggest it was a prominent entry point into the island for Pre-Columbian trade. Although the town of Fajardo was founded in 1760 close to the south around the river of the same name, the area of the peninsula was not settled at the time. Throughout the 18th century these headlands were a hotspot for smuggling, which later prompted the establishment of a port to regulate trade and commerce in the area in 1820. A lighthouse was built in the summit of the highest point of Cabezas de San Juan in 1880, and inaugurated on May 2, 1882. The peninsula and the lighthouse itself played a role later at the Battle of Fajardo in the Puerto Rico campaign of the Spanish–American War when Spanish troops under the command of Captain Pedro del Pino successfully repelled a US landing under the command of Rear Admiral Frederick Rodgers in August of 1898, who only managed to capture the lighthouse.
The peninsula itself became a wildlife refuge in 1975 when it was acquired by the Conservation Trust of Puerto Rico, it was later proclaimed a nature reserve in 1986. Hurricane Hugo made landfall in the cape and crossed the reserve as a strong Category 3 storm on September 18, 1989, after having devastated the island of Vieques earlier that same day.
Recreation
Cabezas de San Juan Nature Reserve today is owned and managed by the Conservation Trust of Puerto Rico, and it is open to the public. The lighthouse operates now as a museum, also managed by the Conservation Trust of Puerto Rico.
See also
Protected areas of Puerto Rico
References
IUCN Category V
Bioluminescence
Fajardo, Puerto Rico
Protected areas established in 1975
Protected areas established in 1986
Protected areas of Puerto Rico
Tourist attractions in Puerto Rico
1975 establishments in Puerto Rico
1986 establishments in Puerto Rico
Spanish–American War | Las Cabezas de San Juan (Puerto Rico) | [
"Chemistry",
"Biology"
] | 913 | [
"Biochemistry",
"Luminescence",
"Bioluminescence"
] |
78,400,292 | https://en.wikipedia.org/wiki/Marina%20Iliopoulou | Marina Iliopoulou () is a Greek mathematician. Her main research focus is harmonic analysis, but she has also published research in discrete geometry including new results on the Erdős–Anning theorem. She is a professor of mathematics at the National and Kapodistrian University of Athens.
Education and career
Iliopoulou did her undergraduate studies in mathematics at the National and Kapodistrian University of Athens, finishing in 2009. She received a Ph.D. in 2013 from the University of Edinburgh in Scotland, with the dissertation Discrete analogues of Kakeya problems supervised by Tony Carbery.
After postdoctoral research at the University of Birmingham in England and the Mathematical Sciences Research Institute and University of California, Berkeley in the US, she became an assistant professor at the University of Kent in England in 2019. In 2022 she took an associate professorship at the University of Birmingham, and in 2023 she returned to the University of Athens as a full professor.
Recognition
Iliopoulou is one of three recipients of the 2024 L'Oréal-UNESCO Greek Awards for Women in Science.
References
External links
Home page
Year of birth missing (living people)
Living people
21st-century Greek mathematicians
Greek women mathematicians
Mathematical analysts
National and Kapodistrian University of Athens alumni
Alumni of the University of Edinburgh
Academics of the University of Kent
Academics of the University of Birmingham
Academic staff of the National and Kapodistrian University of Athens | Marina Iliopoulou | [
"Mathematics"
] | 291 | [
"Mathematical analysis",
"Mathematical analysts"
] |
78,400,335 | https://en.wikipedia.org/wiki/David%20B.%20Weiner | David B. Weiner is an American Biomedical researcher at The Wistar Institute in Philadelphia, where he serves as executive vice president and director of the Vaccines and Immunotherapy Center. Weiner also holds the titles of WW Smith Distinguished Chair in Cancer Research and professor emeritus, Perelman School of Medicine at the University of Pennsylvania.
Biography
Weiner is from Brooklyn, NY, and graduated with a B.S. in biology from SUNY at Stony Brook, NY. He earned both his M.S. in Biology and Ph.D. in development biology from the University of Cincinnati.
Weiner is regarded as one of the founders of the field of DNA vaccines and detailed many of the initial properties of the technology. His laboratory described DNA vaccine technology as an approach to HIV vaccine development and for the immune therapy of cancer, and in 1998, Weiner and his associates were the first to move DNA vaccines into human clinical trials. The Weiner laboratory also reports on adjuvant effects in vaccination protocols by targeting the checkpoint inhibitor pathways, among others.
Weiner has served as the president of International Society for Vaccines (2018-2020), and as chair of the Gene Therapy and Vaccine Training Program at the University of Pennsylvania from 2004-2016, before joining the Wistar Institute. He and his lab had a cameo appearance in the 1993 movie Philadelphia starring Tom Hanks.
Research
Weiner’s research focuses on translational applications of molecular immunology. His early work developed monoclonal antibodies as therapeutics targeting tumors and infections, and the lab continues to pursue nucleic acid vaccines and immunotherapies. The lab has been involved in several clinical trials.
References
External links
Research articles on Pubmed
Clinical trials on Pubmed
American medical researchers
Living people
Year of birth missing (living people)
Vaccinologists | David B. Weiner | [
"Biology"
] | 370 | [
"Vaccination",
"Vaccinologists"
] |
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