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75,250,402 | https://en.wikipedia.org/wiki/Resigratinib | Resigratinib (KIN-3248) is an experimental anticancer medication which acts as a fibroblast growth factor receptor inhibitor (FGFRi) and is in early stage human clinical trials.
See also
Enbezotinib
Pralsetinib
Rebecsinib
Selpercatinib
Zeteletinib
References
Enzyme inhibitors
Experimental monoclonal antibodies
Benzimidazoles
Pyrazolecarboxamides
Pyrrolidines
Enols
Methoxy compounds
Secondary amines
Fluoroarenes
Cyclopropyl compounds | Resigratinib | [
"Chemistry"
] | 119 | [
"Enols",
"Pharmacology",
"Functional groups",
"Medicinal chemistry stubs",
"Pharmacology stubs"
] |
75,251,055 | https://en.wikipedia.org/wiki/Poultry%20microbiome | The poultry microbiome is an understudied, yet extremely impactful part of the poultry industry. Poultry is defined as any avian species used for production purposes such as food or down feathers. The United States consumes more poultry, specifically broiler meat, than any other type of protein. Worldwide, poultry makes up 33% of consumed meat. This makes poultry extremely valuable and the impact of the poultry microbiome on health and production even more valuable. Antonie van Leeuwenhoek was the first to notice microbes inside animals through stool samples giving light to further research into the gut microbiome. His discovery lead to the ever evolving study of the microbiota and microbiome. The microbiota is the entirety of living organisms including bacteria, viruses, fungi, and archaea in an environment. The microbiome is the combination of the microbiota and the additional activities in that system including metabolites and chemicals in a habitat. Much of the work done to characterize the poultry microbiome has been accomplished over the past decade and was done through the use of 16s rRNA sequencing.
Production impacts
The poultry microbiome includes all living microbes found in and on the bird as well as in the environment. However, studies of the microbes that are important to production have concentrated heavily within the digestive tract. Increased amounts of Lactobacillus, Cornyebacterium, Coprobacillus and Slakia found in the ceca of chickens has been shown to increase feed conversion ratios in broiler chickens. The opposite can be said for Akkermansia muciniphila and cecal Parabacteriocides which have been shown to have negative effects on feed conversation. In addition, correlations in gut microbiota variance and feed conversion rates have been shown in laying hens. The study on laying hens found that Anaerosporobacter, Candidatus Stoquefichus, and Fournierella are negatively associated with feed conversion in regards to egg production and body weight maintenance. Although understudied, turkeys and ducks are assumed to have very similar feed conversion correlations to microbiome.
Alternatively, the importance of the microbiome in regards to duck hatching egg production has been studied. Evidence shows that ducks with more diverse microbiota in their bedding or litter, specifically containing large amounts of Staphylococcus, Corynebacterium, and Brevibacterium have worse egg quality and hatching rates. The environment that poultry are raised in can have a significant impact on their production because it can significantly impact the microbes that they are exposed to and that ultimately colonize inside and on the birds.
Pathogen colonization
Pathogen colonization is one of the most important parts of the poultry microbiome because it affects both the birds health as well as consumers health. The most well known bacterial pathogen in regards to poultry in Salmonella because of its risk to human health and high prevalence. Salmonella can easily colonize in the intestines of poultry, however some studies are working with targeted phages to remove salmonella from the microbiome of broiler chickens. Salmonella Typhimurium is a human pathogen, that poses a risk to consumers because of its ability to colonize the poultry digestive tract without harming the bird. Fortunately, researchers are studying different microbial interactions, such as probiotics, and metabolite influences on preventing Salmonella colonization and restoring healthy gut microbiota after infection. Another pathogen that can colonize the gut of poultry is Clostridium perfringens. Types A and C of this bacterium can cause necrotic enteritis, characterized by decaying and inflamed intestinal tissue. However this is only under certain dietary conditions and in combination with the parasite coccidia. In a study conducted in 2021 where researchers worked to characterize the bacterial make-up of the turkey respiratory tract they found that the presence of Ornithobacterium and Mycoplasma, puts turkeys at a higher risk for respiratory infections. It has also been shown in turkeys that domesticated turkeys have less microbial diversity and more pathogenic and antibiotic resistant strains of bacteria persistent in their gut than their wild counterparts.
Anatomical areas
Feathers and skin
The exterior of poultry is covered in some combination of feathers and skin that has a unique microbiome based on its metabolites and exposure to the environment. Skin and feather bacteria are often aerobic due to the exposer to oxygen. There appears to be no difference in flagellated vs non flagellated bacteria being present on or attaching to the exterior of the chicken. The microbiome of the exterior of the chicken is of extreme concern to the poultry processing industry because of avoiding pathogen presence for food consumption.
Digestive tract
The digestive tract of the avian species is different than all other animals. The avian digestive system includes the esophagus, crop, proventriculus, gizzard, duodenal loop, jejunum, ileum, ceca, large intestine and cloaca. Each on these sections has a unique pH and microbiota living inside it. In ducks Bacteroidetes have been found to be the prominent phyla found in the ceca. Where as, the other regions of the digestive tract were more diverse supporting Firmicutes, Proteobacteria, Bacteroidetes, Cyanobacteria, and Actinobacteria. It is also noted that the digestive tract increases in abundance and diversity of bacteria as you move from the proventriculus to the cloaca or rectum of the bird.
Reproductive tract
The reproductive tract, also known as the oviduct, is equally as diverse as the digestive tract in differentiated areas and differences in chemical and physiological properties. The female poultry reproductive tract consists of the ovary, infundibulum, magnum, isthmus, shell gland, vagina, and cloaca. Meanwhile, the male chicken and turkeys reproductive tract consists of the testis, ductus deferens, ejaculatory duct, and cloaca. In ducks the male anatomy is slightly different due to the presence of a penis. The microbiome in the oviduct of turkeys has been characterized with 19 phyla, including several pathogenic species and has been linked to juvenile turkey health. In addition, researchers have found that there is a strong correlation between Bacteroides fragilis, Bacteroides salanitronis, Bacteroides barnesiae, and Clostridium leptum being present in the vagina and reproductive tract of a laying hen and her producing a higher quantity and quality of eggs.
References
Wikipedia Student Program
Microbiomes
Poultry | Poultry microbiome | [
"Environmental_science"
] | 1,401 | [
"Microbiomes",
"Environmental microbiology"
] |
66,541,188 | https://en.wikipedia.org/wiki/Bovista%20paludosa | Bovista paludosa is a species of fungus belonging to the family Lycoperdaceae.
It is native to Eurasia.
References
Lycoperdaceae
Taxa named by Joseph-Henri Léveillé
Fungi of Europe
Fungi of Asia
Fungi described in 1846
Fungus species | Bovista paludosa | [
"Biology"
] | 57 | [
"Fungi",
"Fungus species"
] |
66,541,220 | https://en.wikipedia.org/wiki/Bohlmann%E2%80%93Rahtz%20pyridine%20synthesis | In organic chemistry, the Bohlmann–Rahtz pyridine synthesis is a reaction that generates substituted pyridines in two steps, first a condensation reaction between an enamine and an ethynylketone to form an aminodiene intermediate, which after heat-induced E/Z isomerization undergoes a cyclodehydration to yield 2,3,6-trisubstituted pyridines.
References
Name reactions
Pyridine forming reactions | Bohlmann–Rahtz pyridine synthesis | [
"Chemistry"
] | 103 | [
"Name reactions",
"Chemical reaction stubs",
"Ring forming reactions",
"Organic reactions"
] |
66,541,277 | https://en.wikipedia.org/wiki/Sack%E2%80%93Schamel%20equation | The Sack–Schamel equation describes the nonlinear evolution of the cold ion fluid in a two-component plasma under the influence of a self-organized electric field. It is a partial differential equation of second order in time and space formulated in Lagrangian coordinates. The dynamics described by the equation take place on an ionic time scale, which allows electrons to be treated as if they were in equilibrium and described by an isothermal Boltzmann distribution. Supplemented by suitable boundary conditions, it describes the entire configuration space of possible events the ion fluid is capable of, both globally and locally.
The equation
The Sack–Schamel equation is in its simplest form, namely for isothermal electrons, given by
is therein the specific volume of the ion fluid, the Lagrangian mass variable and t the time (see the following text).
Derivation and application
We treat, as an example, the plasma expansion into vacuum, i.e. a plasma that is confined initially in a half-space and is released at t=0 to occupy in course of time the second half.
The dynamics of such a two-component plasma, consisting of isothermal Botzmann-like electrons and a cold ion fluid, is governed by the ion equations of continuity and momentum, and , respectively.
Both species are thereby coupled through the self-organized electric field , which satisfies Poisson's equation, . Supplemented by suitable initial and boundary conditions (b.c.s), they represent a self-consistent, intrinsically closed set of equations that represent the laminar ion flow in its full pattern on the ion time scale.
Figs. 1a, 1b show an example of a typical evolution. Fig. 1a shows the ion density in x-space for different discrete times, Fig. 1b a small section of the density front.
Most notable is the appearance of a spiky ion front associated with the collapse of density at a certain point in space-time . Here, the quantity becomes zero. This event is known as "wave breaking" by analogy with a similar phenomenon that occurs with water waves approaching a beach.
This result is obtained by a Lagrange numerical scheme, in which the Euler coordinates are replaced by Lagrange coordinates , and by so-called open b.c.s, which are formulated by differential equations of the first order.
This transformation is provided by , , where is the Lagrangian mass variable. The inverse transformation is given by and it holds the identity: . With this identity we get through an x-derivation or . In the second step the definition of the mass variable was used which is constant along the trajectory of a fluid element: . This follows from the definition of , from the continuity equation and from the replacement of by . Hence . The velocity of a fluid element coincides with the local fluid velocity.
It immediately follows: where the momentum equation has been used as well as , which follows from the definition of and from .
Replacing by we get from Poisson's equation: . Hence . Finally, replacing in the expression we get the desired equation:. Here is a function of : and for convenience we may replace by . Further details on this transition from one to the other coordinate system can be found in.
Note its unusual character because of the implicit occurrence of . Physically V represents the specific volume. It is equivalent with the Jacobian J of the transformation from Eulerian to Lagrangian coordinates since it holds
Wave-breaking solution
An analytical, global solution of the Sack–Schamel equation is generally not available. The same holds for the plasma expansion problem. This means that the data for the collapse cannot be predicted, but have to be taken from the numerical solution. Nonetheless, it is possible, locally in space and time, to obtain a solution to the equation. This is presented in detail in Sect.6 "Theory of bunching and wave breaking in ion dynamics" of. The solution can be found in equation (6.37) and reads for small and t
where are constants and stand for . The collapse is hence at . is V-shaped in and its minimum moves linearly with towards the zero point (see Fig. 7 of ). This means that the density n diverges at when we return to the original Lagrangian variables.
It is easily seen that the slope of the velocity, , diverges as well when . In the final collapse phase, the Sack–Schamel equation transits into the quasi-neutral scalar wave equation: and the ion dynamics obeys Euler's simple wave equation: .
Generalization
A generalization is achieved by allowing different equations of state for the electrons. Assuming a polytropic equation of state, or with : where refers to isothermal electrons, we get (see again Sect. 6 of ):
The limitation of results from the demand that at infinity the electron density should vanish (for the expansion into vacuum problem). For more details, see Sect. 2: "The plasma expansion model" of or more explicitly Sect. 2.2:
"Constraints on the electron dynamics".
Fast Ion Bunching
These results are in two respects remarkable. The collapse, which could be resolved analytically by the Sack–Schamel equation, signalizes through its singularity the absence of real physics. A real plasma can continue in at least two ways.
Either it enters into the kinetic collsionless Vlasov regime and develops multi-streaming and folding effects in phase space or it experiences dissipation (e.g. through Navier-Stokes viscosity in the momentum equation
) which controls furtheron the evolution in the subsequent phase.
As a consequence the ion density peak saturates and continues its acceleration into vacuum maintaining its spiky nature. This phenomenon of fast ion bunching being recognized by its spiky fast ion front has received immense attention in the recent past in several fields. High-energy ion jets are of importance and promising in applications such as in the laser-plasma interaction, in the laser irradiation of solid targets, being also referred to as target normal sheath acceleration, in future plasma based particle accelerators and radiation sources (e.g. for tumor therapy) and in space plasmas.
Fast ion bunches are hence a relic of wave breaking that is analytically completely described by the Sack–Schamel equation. (For more details especially about the spiky nature of the fast ion front in case of dissipation see http://www.hans-schamel.de or the original papers ). An article in which the Sack-Schamel's wave breaking mechanism is mentioned as the origin of a peak ion front was published e.g. by Beck and Pantellini (2009).
Finally, the notability of the Sack–Schamel equation is clarified through a recently published molecular dynamics simulation. In the early phase of the plasma expansion a distinct ion peak could be observed, emphasizing the importance of the wave breaking scenario as predicted by the equation.
References
External links
www.hans-schamel.de further information by Hans Schamel
Partial differential equations
Laser applications
Plasma physics equations | Sack–Schamel equation | [
"Physics"
] | 1,460 | [
"Equations of physics",
"Plasma physics equations"
] |
66,542,085 | https://en.wikipedia.org/wiki/European%20Vaccine%20Initiative | The European Vaccine Initiative (EVI) is a non-profit Product Development Partnership (PDP) with the goal of supporting and accelerating the development of effective and affordable vaccines for global health. Since its inception in 1998, EVI has operated as an independent non-profit organisation that works closely with academic researchers, the private sector, governments, and other organisations to spearhead vaccine development. Headquartered in Heidelberg, Germany, EVI collaborates with partners across the world to pursue its mission.
Background
The predecessor of EVI, the European Malaria Vaccine Initiative (EMVI) was established in 1998 with the specific aim of accelerating malaria vaccine development in Europe. Initially hosted by the University of Bergen in Norway, EMVI later moved to Copenhagen, Denmark where it was hosted by the Statens Serum Institute (SSI). In 2010, the name of the organisation was changed to EVI to reflect a broader scope of activities. At the same time, the headquarter of the organisation was moved to Heidelberg, Germany and the legal status was changed to a European Economic Interest Grouping (EEIG) with Stockholm University and Heidelberg University as the founding institutions. Although malaria vaccine development remains an important activity for EVI, today EVI is dedicated to support and accelerate the development of effective, accessible, and affordable vaccines for other diseases of importance for global health.
Organisation and governance
EVI is established as an Association (e.V) under German law, with a recognised status as a non-profit organisation. The founding institutions of EVI were Stockholm and Heidelberg Universities, and the current members of the Association are the Biomedical Primate Research Centre, Rijswijk; Heidelberg University, Heidelberg; the Jenner Vaccine Foundation, Oxford; Pasteur Institute, Paris, and the Royal College of Surgeons in Ireland, Dublin. Each of the constituent members is represented on the Board of Directors, which approves policies, organisational strategy and budget. The Chairman of EVI's Board is Dr Clemens Kocken, while EVI has been led since 2020 by Executive Director Ole F. Olesen.
Each constituent member is represented in the General Assembly, which approves policies, organisational strategy and budget. The Chairman of EVI's General Assembly is Dr Clemens Kocken, the vice-chair is Samuel McConkey, while EVI has been led since 2020 by Executive Director Ole F. Olesen.
Funding
EVI's work is funded by donors including Coalition for Epidemic Preparedness Innovations (CEPI), European & Developing Countries Clinical Trials Partnership (EDCTP), European Union (EU), Global Health Innovative Technologies Fund (GHIT), Innovative Medicines Initiative (IMI), Nobelpharma Co., Ltd., World Health Organization - Special Programme for Research and Training in Tropical Diseases (TDR), the Dutch Ministry of Foreign Affairs, the Danish International Development Agency (Danida), the Department of Foreign Affairs (Irish Aid), the Dutch Research Council, the German Federal Ministry of Education and Research (BMBF) through KfW, and the Swedish Ministry of Foreign Affairs, Swedish International Development Cooperation Agency (Sida).
Research and development activities
EVI operates in three complementary areas:
Translational vaccine development and early clinical testing: this area is dedicated to supporting and coordinating pre-clinical research, clinical testing and development of individual vaccine candidates, for diseases of poverty and emerging infectious diseases. EVI has supported the development of vaccine candidates for diseases such malaria, zika fever, nipah infection, diarrheal diseases, dengue fever, and leishmaniasis. It has supported the testing and development of 40 different vaccine formulations that have progressed into clinical development.
Cross-cutting activities: this area is focused on tackling the gaps in vaccine research and development (R&D) through overarching initiatives such as supporting the implementation of a vaccine R&D infrastructure in Europe, harmonization, knowledge sharing, development and standardisation of assays, development of human challenge models, and capacity building and advocacy.
Improving vaccine uptake and knowledge-sharing: dedicated to extending the benefits of vaccines by improving knowledge access and uptake of vaccines. EVI has also engaged in the strengthening of research capacity in low- and middle-income countries, particularly in sub-Saharan Africa.
References
External links
Official website
Heidelberg
Scientific organizations established in 1998
1998 establishments in Germany
International medical and health organizations
Vaccines
Organisations based in Baden-Württemberg | European Vaccine Initiative | [
"Biology"
] | 894 | [
"Vaccination",
"Vaccines"
] |
66,542,773 | https://en.wikipedia.org/wiki/Odysee | Odysee is an American decentralized video hosting platform built on the LBRY blockchain. It positions itself as an alternative to mainstream services like YouTube, but with a focus on free speech and decentralization.
The platform enables users to upload, share, and monetize videos through crypto currency, while maintaining content persistence through a peer-to-peer network.
History
Odysee was founded in 2020 by Julian Chandra.
In June 2024, Odysee was acquired by Forward Research. The acquisition took place after Odysee's former parent company LBRY lost a lawsuit from the U.S. Securities and Exchange Commission in July 2023.
Technology
Odysee is driven by blockchain, a decentralized protocol that allows digital content to be distributed and stored without a central authority. This blockchain network supports a peer-to-peer infrastructure, which allows users to upload and share videos. The metadata of uploaded content is stored on the blockchain, while the videos themselves are hosted across a distributed network of users, referred to as nodes.
Moderation
Since its launch in September 2020, Odysee has been at the center of several controversies, primarily due to its content moderation policies and decentralized structure, which critics argue have allowed harmful content to flourish. The platform's approach to content moderation, which is significantly less restrictive compared to mainstream platforms like YouTube, has attracted a range of users, including far-right groups, conspiracy theorists, and individuals banned from other platforms.
In addition to allegations of facilitating hate speech, Odysee has also been criticized for hosting disinformation, particularly around topics such as the COVID-19 pandemic, vaccines, and political issues. The platform's decentralized nature makes it difficult for content to be effectively moderated or removed, allowing misinformation and disinformation to spread without significant resistance. This has raised concerns about the proliferation of conspiracy theories related to elections, public health, and other widely debunked claims.
Odysee has faced geo-blocking restrictions in regions such as the European Union, where governments have raised concerns about content deemed harmful or disinformation.
Arweave
Arweave is a decentralized network for permanent data storage, meant to ensure long-term availability of data. It uses a Proof of Access mechanism providing an incentive to store the data that has been uploaded to the network. The native cryptocurrency of the Arweave network is called AR, which is used to pay for data storage.
Forward Research, the company developing Arweave acquired Odysee in 2024. Odysee is in the process of transitioning to Arweave's technology.
Blockweave
The Arweave network utilizes a blockchain-like technology called the "blockweave", focusing on data storage.
SmartWeave
SmartWeave is a smart contract protocol that operates on Arweave. Contract state is computed on-demand by the caller, reducing network load.
Permaweb
The Permaweb is Arweave's decentralized, permanent web of webpages, apps, and files stored on top of the Arweave network.
See also
Online video platform
Comparison of video hosting services
List of online video platforms
References
Social media
Video hosting
Video search engine
Companies based in Las Vegas
American companies established in 2020
Blockchains
Freedom of speech
Cryptocurrencies
Free and open-source software
Internet properties established in 2020
Social networking services | Odysee | [
"Technology"
] | 722 | [
"Computing and society",
"Social media"
] |
66,543,604 | https://en.wikipedia.org/wiki/Conservation%20welfare | Conservation welfare is a proposed discipline which would focus on establishing the commonalities between conservation and animal welfare and the formation of a foundation upon which the two disciplines can collaborate to further their respective objectives. It would be based on the principles of Peter Singer's utilitarianism and similarly to compassionate conservation, its focus would diverge from environmental ethics in that it concentrates on the welfare of individual animals, rather than species, ecosystems or populations. It has been argued that conservation welfare would be distinct from compassionate conservation because the two disciplines have differing conceptions of the harms experienced by wild animals and that while conservation welfare would seek to engage with conservation scientists and integrate animal welfare into existing conservation practices, compassionate conservation may lack the capacity to "guide decision-making in complex or novel situations."
See also
Relationship between animal ethics and environmental ethics
References
Animal welfare
Environmental conservation
Environmental ethics | Conservation welfare | [
"Environmental_science"
] | 176 | [
"Environmental ethics"
] |
66,544,639 | https://en.wikipedia.org/wiki/Sequence%20analysis%20of%20synthetic%20polymers | The methods for sequence analysis of synthetic polymers differ from the sequence analysis of biopolymers (e. g. DNA or proteins). Synthetic polymers are produced by chain-growth or step-growth polymerization and show thereby polydispersity, whereas biopolymers are synthesized by complex template-based mechanisms and are sequence-defined and monodisperse. Synthetic polymers are a mixture of macromolecules of different length and sequence and are analysed via statistical measures (e. g. the degree of polymerization, comonomer composition or dyad and triad fractions).
NMR-based sequencing
Nuclear magnetic resonance (NMR) spectroscopy is known as the most widely applied and “one of the most powerful techniques” for the sequence analysis of synthetic copolymers. NMR spectroscopy allows determination of the relative abundance of comonomer sequences at the level of dyads and in cases of small repeat units even triads or more. It also allows the detection and quantification of chain defects and chain end groups, cyclic oligomers and by-products. However, limitations of NMR spectroscopy are that it cannot, so far, provide information about the sequence distribution along the chain, like gradients, clusters or a long-range order.
Example: Copolymer of PET and PEN
Monitoring the relative abundance of comonomer sequences is a common technique and is used, for example, to observe the progress of transesterification reactions between polyethylene terephthalate (PET) and polyethylene naphthalate (PEN) in their blends.
During such a transesterification reaction, three resonances representing four diads can be distinguished via 1H NMR spectroscopy by different chemical shifts of the oxyethylene units: The diads -terephthalate-oxyethylene-terephthalate- (TET) and -naphthalate-oxyethylene-naphthalate- (NEN), which are also present in the homopolymers polyethylene naphthalate und polyethylene terephthalate, as well as the (indistinguishable) diads -terephthalate-oxyethylene-naphthalate- (TEN) and -naphthalate-oxyethylene-terephthalate- (NET), which are exclusively present in the copolymer. In the spectrum of a 1:1 physical PET/PEN mixture, only the resonances corresponding to the diads TET and NEN are present at 4.90 and 5.00 ppm, respectively. Once a transesterification reaction occurs, a new resonance at 4.95 ppm emerges that increases in intensity with the reaction time, corresponding to the TEN / NET sequences.
The example of polyethylene naphthalate and polyethylene terephthalate is relatively simple, as only the aromatic part of the polymers differ (naphthalate vs. terephthalate). In a blend of polyethylene naphthalate and polytrimethylene terephthalate, already six resonances can be distinguished, since both, oxyethylene and oxypropylene, form three resonances. The sequence patterns can become even more complex, when triads can be distinguished spectroscopically. The extractable information is limited by the difference in chemical shift and the resonance width. In addition to 1H NMR spectroscopy, also 13C NMR spectroscopy is a common method for the sequencing shown above, which is characterized in particular by a very narrow resonance width.
Deconvolution and assignment of these triad-based resonances allows a quantitative determination of the degree of randomness and the average block length via integration of the distinguishable resonances. In a 1:1 mixture of two linear two-component 1:1 polycondensates (A1B1)n and (A2B2)n (with molecular weight high enough to neglected chain-ends), the following two equations are valid:
[ Ai] = [Bi], wherein (i = 1,2) (1)
[ A1B2 ] = [ A2B1] (2)
Equation 1 states that the molar ratio of all four repeat units is identical and equation 2 states that both types of copolymer are of identical concentration. In this case, the degree of randomness χ is calculated as given by equation 3:
, wherein (i, j = 1, 2) (3)
In the beginning of a transreaction process (e. g. transesterification or transamidation), the degree of randomness χ ≈ 0 as the system comprises a physical mixture of homopolymers or block copolymers. During the transreaction process χ increases up to χ = 1 for a fully random copolymer. If χ > 1 it indicates a tendency of the monomers to form alternating structure, up to χ = 2 for a completely alternating copolymer. The degree of randomness χ gives thereby statistical information about the polymer sequence. The calculation can be modified for three-component and four-component polycondensates.
Application
NMR spectroscopy is used in industrially relevant systems to study the sequence distribution of copolymers or the occurrence of transesterification in polyester blends. A change in sequence distribution can effect the crystallinity, and transesterification can affect the compatibility of two otherwise incompatible polyesters. Depending on their degree of randomness, copolyesters can show different thermal transitions and behaviours.
Other sequencing
Other options besides traditional NMR spectroscopy for sequence analysis are listed here; these include Kerr-effect for characterization of polymer microstructures, MALDI-TOF mass spectrometry, depolymerization (controlled chemical degradation of macromolecules) via chain-end depolymerization (i.e., unzipping) and nanopore analysis (most of such reported studies, however, have focused on poly(ethylene glycol), PEG).
References
Polymer chemistry | Sequence analysis of synthetic polymers | [
"Chemistry",
"Materials_science",
"Engineering"
] | 1,275 | [
"Materials science",
"Polymer chemistry"
] |
66,546,481 | https://en.wikipedia.org/wiki/HALO%20Urban%20Regeneration | HALO Urban Regeneration is a Scottish business innovation park, urban regeneration and business start-up support company, founded, based and headquartered in Kilmarnock, East Ayrshire, Scotland. The HALO Urban Regeneration was founded by entrepreneur Marie Macklin CBE in 2006 as HALO Urban Regeneration Company Ltd., having announced the project a few years prior to official funding and creation of the HALO Kilmarnock.
The HALO building on Hill Street, Kilmarnock, is a £63 million brownfield urban regeneration project constructed on a 23-acre site, formerly the home of Johnnie Walker, the world’s leading Scotch whisky brand that was founded in Kilmarnock in 1820 and operated on the site until Diageo closed the Kilmarnock plant in 2012.
HALO is projected to generate £205 million to the Economy of Scotland and stimulate 1,500 jobs.
History
HALO Scotland
Following the 2009 announcement of the closure of the Johnnie Walker whisky bottling unit and production factory in Kilmarnock, owners Diageo began seeking proposals for future leasing of the Hill Street site that occupied that 32-acre site at that time. Diageo gifted eight acres to Kilmarnock College (a campus of Ayrshire College since 2013) in 2012 to allow the construction of a new multi-million pound campus to replace the ageing building that was constructed during the 1960s. Marie Macklin CBE, Chief Executive of The KLIN Group at the time, who had already undertaken numerous projects in and around Kilmarnock to restore derelict buildings in the town centre, submitted a proposal for a new, innovative hub to provide office space for startup companies and opportunities to enhance Kilmarnock's urban regeneration work.
A planning application for permission for construction work on the new project was submitted to the planning advisory board of East Ayrshire Council, was planning permission granted by the council in 2018. The cost of the development was estimated to be £65 million, with the Scottish Government announcing a £5.3 million investment in the HALO Project in August 2017, with £1.8 million to be focused on low carbon emissions which was ultimately unused.
Morrison Construction was appointed as main contractors for the construction of the complex in September 2019, with construction work initially scheduled to be completed by January 2021, however this was delayed as a result of the halt on construction works in Scotland due to the COVID-19 pandemic and phase one opened March 2022
The HALO Urban Regeneration benefitted as part of the Ayrshire Growth Deal, an economic recovery agreement between the Scottish Government, UK Government and the councils of East Ayrshire, North Ayrshire and South Ayrshire, with the Scottish Government and UK Government both providing £3.5 million of investment for the company and the regeneration of the former Johnnie Walker site. Diageo who owned the land when occupied by the former Johnnie Walker bottling and production plant facility donated the land for a cost of £1 and under the Ayrshire Growth Deal has been committed to a contribution of £2 million to support planning and design of the HALO development as well as long-term sustainability of the Hill Street site as a consequence for closing the Johnnie Walker facility.
The building in Kilmarnock is a 4-storey mixed used structure and constructed from three main materials - dark brick, curtain wall glazing and a perforated aluminium screen at roof level, features a round LED dome on the roof which illuminates at nighttime. Phase 1 of the complex was completed in July 2021 (the HALO Enterprise & Innovation Hub), with future phases of the sites development consisting of a series of live and work units, a leisure facility, nursery, and over 200 houses. The building has become a symbol of regeneration in Kilmarnock, both in terms of redevelopment of land as well as economic regeneration and recovery.
Expansion
A second HALO project is scheduled to begin planning and construction in Northern Ireland.
The HALO is scheduled to begin planning and construction of new premises to focus on urban regeneration projects in both Wales and England. The timescale for completion on these projects in England, Wales and Northern Ireland have still to be announced.
Services
Key services
The Halo Urban Regeneration is founded with a particular focus on:
Urban regeneration of Kilmarnock and Ayrshire
Providing business and financial support for small startup businesses
Office space for companies
Residential houses
Live Work Studios (#RockMe)
Education and employment programmes
Urban Park, including entrepreneurial businesses from computer technology, cyber research, engineering, fashion, financial services and light manufacturing
A Fashion Foundry for small businesses designing, producing and retailing fashionwear and providing training skills for the new digital age will complement the digital retail boutique shopping arcade.
A Children's Innovation Centre will engage with young people of all ages, from eco-nursery through to higher education, working in partnership with local schools, colleges and universities.
Leisure and community amenities will include a WAVE Surf water feature built to Olympic training standards, as well as a skateboard park and other activity areas for all ages.
Business intentions
The HALO Urban Regeneration has a particular focus on, and intention to:
Provide flexible, affordable workspace in an inspiring environment for entrepreneurs with spin-out, start-up and step-up businesses.
Produce an informed and skilled supply of employment-ready young people to sharpen the technical and commercial competitive edges of businesses, especially in the retail and business service sectors.
Create and sustain leading-edge learning facilities and opportunities to support widening access and inclusive growth for all communities, but particularly raising aspirations of children and young adults.
Business partnerships
The HALO Urban Regeneration has established business partnerships with various companies and organisations to support the business in its key business strategy. Most notably, HALO Urban Regeneration focuses on education and youth employment opportunities and includes partners such as:
East Ayrshire Council
The Scottish Government
The UK Government
Diageo
Scottish Power
CGI
Onecom
Scottish Business Resilience Centre
Barclays
A business partnership in association with Scottish Power makes the energy company the main HALO Platinum Partner and Sponsor. Scottish Power launched a £5 million, five-year programme, with a focus on building and enhancing the companies focus and vision of “Utility of the Future” vision. The Halo Urban Regeneration claim that the company will be a leader in the HALO Innovation and Enterprise Centre and the Digital and Cyber Zone. HALO and Scottish Power have committed to working together to create a cyber and digital training and learning facility, at the forefront of the ‘Fourth Industrial Revolution’.
The HALO Urban Regeneration developed a partnership with Barclays in order to enhance HALO's employability initiatives for individuals in Ayrshire, seeks to eradicate barriers those facing unemployment of any age many experience, through Barclays LifeSkills, allowing individuals to access education and digital technology. Additionally, the Barclays-HALO partnership seeks to help start-up and scale-up entrepreneurial businesses to capitalise on growth opportunities, as well as enhancing connectivity and collaboration with other businesses locally and across the UK. In 2019, Barclays launched their first Thriving Local Economies initiative in Kilmarnock as a result of their partnership with The Halo Urban Regeneration, with a particular focus on strategies to boost and enhance the economy of Kilmarnock.
Economic performance
The HALO Urban Regeneration company aims to create and sustain over 1,500 jobs within Kilmarnock as well as a projected contribution of £205 million in Gross Domestic Product revenue to the Economy of Scotland.
PRA Group
Ayrshire College
As part of the sale of the 32-acre site by Diageo, Ayrshire College was granted part of the site which neighbours the HQ and office space of The Halo Urban Regeneration. Due to the close proximity and sharing the site, the company has formed an ambitious partnership with Ayrshire College to ensure the integration of the college with The HALO Urban Regeneration to progress a deep range of practical learning experiences for students, as well as developing new qualifications for Ayrshire College students, ranging from qualifications within the construction section, digital skills market, as well as social care and design.
The HALO Urban Regeneration seeks to create a skilled workforce within Kilmarnock and Ayrshire as a result of its educational and business partnership with Ayrshire College.
In 2020, an NPA qualification was founded in collaboration with The HALO Urban Regeneration, Ayrshire College and construction contractors Morrisons Construction, with students able to access work placements on site during the construction process site.
Board of management
Marie Macklin CBE, founder and executive chair
The current board composition of the HALO Urban Regeneration consists of:
Marie Macklin CBE, Founder and executive chair
Derek Weir, Managing director
Drew Macklin, Project director
Gary Deans, Financial and enterprise director
Bill Stafford, non-executive director
Jim McMahon, non-executive director
See also
Kilmarnock
East Ayrshire
Johnnie Walker, the site on which the HALO Urban Regeneration has been constructed
Economy of Scotland
Kilmarnock College
Ayrshire College
References
Buildings and structures in Kilmarnock
Companies of Scotland
Organisations based in East Ayrshire
2015 establishments in Scotland
Economy of Scotland
Business organisations based in Scotland
Urban renewal
Redevelopment
Government aid programs
Entrepreneurship organizations
Buildings and structures completed in 2021 | HALO Urban Regeneration | [
"Engineering"
] | 1,846 | [
"Construction",
"Redevelopment"
] |
66,549,184 | https://en.wikipedia.org/wiki/Buchetta%20shop | A buchetta shop or sportello shop is a shop which sells goods through a small hole in the wall; the hole is called a buchetta or sportello (literally, a small opening or window). Such shops are typical of Tuscany, Italy. Many buchettas are found in the historic center of Florence. In English, if they sell wine, they may be called wine windows; food and gelato are also sold in this way.
Buchettas are typically of similar dimensions, about tall and wide, and arched at the top, but are otherwise very diverse in style. They were usually built into the streetside walls of the palaces of aristocrats, usually near the main entrance, and may be quite ornate. They were closed outside of opening hours with a hatch, which might be painted various colours, or with a still life or religious painting. Many hatches are now missing, and some buchettas are disused and have been sealed off.
History
In 1559, Cosimo I de' Medici, Grand Duke of Tuscany, permitted agriculturalists to sell their wine directly to consumers at their residences. As a result, the servants of the rich Florentine houses sold wine from the lord's estates through tiny windows, just large enough to pass a flask through, which came to be called s. In 1759, the Bando Granducale solidified the concept of (sportello shops). This significantly weakened the power of the wine guilds.
At the beginning of the 1900s, the laws on selling wine changed, the palaces were subdivided, and many buchettas were bricked up, or converted to doorbells or mailboxes or niches. A flood in 1966 destroyed many wooden components, but exposed at least one buchetta which had been plastered over, leading to its restoration.
During the plagues of the Renaissance, the sportellos were used as a low-contagion-risk way of conducting commerce. In the COVID-19 pandemic, a few buchettas were reopened to serve that function again. Food, drinks, and gelato were sold. As of 2023, about seven buchettas in Florence are open serving wine and other drinks, with many more visible but blocked or bricked up.
In 2014, Robbin Gheesling completed and extensive street photography project of the Wine Doors of Florence.
References
Further reading
(The Wine Windows Association) maps and seeks protection for buchettas.
Architectural elements
Shops in Italy
Infection-control measures
Renaissance architecture
Arches and vaults
Florence
Windows | Buchetta shop | [
"Technology",
"Engineering"
] | 520 | [
"Building engineering",
"Architectural elements",
"Components",
"Architecture"
] |
66,549,427 | https://en.wikipedia.org/wiki/AB%20Bo%C3%B6tis | AB Boötis, also known as Nova Boötis 1877 and occasionally Nova Comae Berenices 1877, is an object that may have undergone a nova outburst in 1877. It was discovered by Friedrich Schwab at Technische Universität Ilmenau in 1877. He reported observing the star as a 5th magnitude object, visible to the naked eye, on 14 nights during the period from 30 May 1877 through 14 July 1877. During that time interval, his estimate of the star's brightness only changed by 0.42 magnitudes. The star was lost (Schwab noticed its absence on January 9, 1878), and despite several searches in subsequent years, no other 19th century observations of the nova were reported. Downes et al. estimate that Schwab's reported coordinates for the star may have had a precision no better than 1/2 degree. In 1971, A. Sh. Khatisov suggested that the star Schwab saw was BD +21°2606 (whose visual magnitude is 10.64 in the Tycho-2 Catalogue, roughly 100 times fainter than the object Schwab reported), but that identification may be incorrect.
In 1988 Downes and Szkody imaged the area around AB Boötis' reported position, to try to identify the nova in its quiescent state based on its color, but their search was unsuccessful. In 2000, Liu et al. published a spectrum of AB Boötis, which they describe as a cataclysmic variable (a class which includes novae), but they did not publish the coordinates of the star they examined, so exactly which star they observed is unclear. In 2020, Hoffmann and Vogt suggested that AB Boötis might be a re-appearance of a guest star that Chinese astronomers saw near Arcturus in 203 BCE.
References
Novae
Boötes
1877 in science
Boötis, AB
18770530 | AB Boötis | [
"Astronomy"
] | 394 | [
"Novae",
"Astronomical events",
"Boötes",
"Constellations"
] |
66,551,997 | https://en.wikipedia.org/wiki/Shamir%20Optical%20Industry | Shamir Optical Industry Ltd. is an international company headquartered in Kibbutz Shamir, Israel that develops and manufactures optical lenses for eyeglasses . In 2005, the company issued dual listings, on the Tel Aviv Stock Exchange and NASDAQ, becoming the first company from the kibbutz industry to be listed on NASDAQ.
History
The optics factory was established in Kibbutz Shamir in 1972 to meet the need of kibbutz members for non-agricultural work. To this end, the kibbutz signed an agreement with the American company "KMS Industries" (owned by Kip Siegel), to establish a bi-focal lens factory in Israel, with production intended entirely for export.
As part of the agreement, the company, which produced optics for televisions, agreed to provide know-how to the factory and even to buy all its products for the first two years. In 1972, about two years after signing the agreement, Shamir Optical Industry Ltd was established, and the kibbutz optics factory for the production of bi-focal lenses was inaugurated by Pinchas Sapir, Israel Minister of Trade and Industry.
The company expanded its production and started manufacturing progressive lenses in addition to its existing line of lenses in 1984. During that year, the factory's turnover was half a million dollars, and about 20% of the country's optics industry sector originated in the Kibbutz Shamir factory.
In 1990, the company gained a foothold in the United States, with the establishment of its subsidiary, Shamir USA. Eleven years later, Shamir set up a distribution center to supply semi-finished lenses to laboratories across the United States, and for that purpose it set up another company called Shamir Insight Inc.
In 2005, Shamir Optics became a public company, issued on both the Tel Aviv Stock Exchange and NASDAQ at a value of $225.4 million, making it the first kibbutz company to be issued on NASDAQ, and was the only company which has been listed on the American stock exchange that develops multifocal lenses.
In 2008, Shamir strengthened its position in Europe by making the German distribution company, Altra Trading, a wholly owned subsidiary following the acquisition of 49% of its shares, adding to the 51% already held.
The company merged with the French optics company Essilor in 2011. The merger was carried out through the purchase of 37% of shares from the public and another 13% of shares from Shamir Optical Industry Ltd., totaling 50% of the company, for $130 million. Upon completion of the merger with Essilor, Shamir was delisted from NASDAQ and became a private company.
In 2011, Dymotech Ltd filed a $28 million lawsuit against Shamir and its partly owned subsidiary Inray Ltd. Dymotech Ltd. alleged that Shamir and Inray were illegally used Technion's intellectual property, and requested restraining order against them to prevent future use of its alleged intellectual property.
In May 2021, Shamir completed acquisition of Lenstec Optical Group on behalf of its owner Essilor.
In August 2022, EssilorLuxottica completed acquisition of 100% Shamir.
References
Multinational companies headquartered in Israel
Israeli brands
Science and technology in Israel
Life sciences industry | Shamir Optical Industry | [
"Biology"
] | 672 | [
"Life sciences industry"
] |
68,059,192 | https://en.wikipedia.org/wiki/Acetyleugenol | Acetyleugenol is a phenylpropanoid compound found in cloves. It is the second in abundance to the related compound eugenol in certain extract preparations. Like eugenol, its found in several plants such as Acacia nilotica and Piper betle and has similar antibacterial and antifungal properties on C. albicans and S. mutans. It inhibits aggregation of platelets and has partial agonistic activity on AhR.
Uses
Acetyleugenol has characteristic odor reminiscent of cloves and thus used as fragrance.
See also
Methyleugenol
References
Phenylpropanoids
Phenylpropenes
Acetate esters
Methoxy compounds | Acetyleugenol | [
"Chemistry"
] | 149 | [
"Biomolecules by chemical classification",
"Phenylpropanoids"
] |
68,060,170 | https://en.wikipedia.org/wiki/Delgocitinib | Delgocitinib, sold under the brand name Corectim among others, is a medication used for the treatment of autoimmune disorders and hypersensitivity, including inflammatory skin conditions. Delgocitinib was developed by Japan Tobacco and approved in Japan for the treatment of atopic dermatitis. In the United States, delgocitinib is in Phase III clinical trials and the Food and Drug Administration has granted delgocitinib fast track designation for topical treatment of adults with moderate to severe chronic hand eczema.
Delgocitinib works by blocking activation of the JAK-STAT signaling pathway which contributes to the pathogenesis of chronic inflammatory skin diseases.
Society and culture
Legal status
In July 2024, the Committee for Medicinal Products for Human Use of the European Medicines Agency adopted a positive opinion, recommending the granting of a marketing authorization for the medicinal product
Anzupgo, intended for the treatment of chronic hand eczema. The applicant for this medicinal product is LEO Pharma A/S. Anzupgo was approved for medical use in the European Union in September 2024.
References
Dermatologic drugs
Non-receptor tyrosine kinase inhibitors
Pyrrolopyrimidines
Spiro compounds
Nitriles
Amides | Delgocitinib | [
"Chemistry"
] | 262 | [
"Amides",
"Functional groups",
"Organic compounds",
"Nitriles",
"Spiro compounds"
] |
68,060,317 | https://en.wikipedia.org/wiki/Sarolaner | Sarolaner, sold under the brand name Simparica, is an ectoparasiticide veterinary medication for the treatment of flea and tick infestations in dogs. It is also used off-label to control sarcoptic mange and demodectic mange.
Sarolaner is also a component of the combination drug Simparica Trio, which contains sarolaner, moxidectin, and pyrantel. It is used for prevention of heartworm disease caused by Dirofilaria immitis; treat and prevent flea infestations; treat and control tick infestations with the lone star tick, Gulf Coast tick, American dog tick, black-legged tick, and brown dog tick; and treat and control roundworm and adult hookworm infections.
Sarolaner is also an ingredient in feline combination antiparasitic Revolution Plus (or Stronghold Plus), which contains sarolaner and selamectin and is used for prevention of sarcoptic mange, feline hookworms, feline roundworms, ear mites, and heartworms, as well as treating and preventing fleas and ticks.
In November 2024, the FDA approved a supplement that provides for the addition of the indication for the treatment and control of Haemaphysalis longicornis (Asian longhorned tick) infestations for one month in dogs six months of age or older and weighing or greater.
References
Acaricides
Azetidines
Cat medications
Chloroarenes
Dog medications
Fluoroarenes
Insecticides
Isoxazolines
Spiro compounds
Sulfones
Trifluoromethyl compounds
Veterinary medicine | Sarolaner | [
"Chemistry"
] | 341 | [
"Organic compounds",
"Sulfones",
"Functional groups",
"Spiro compounds"
] |
68,062,718 | https://en.wikipedia.org/wiki/Acyl%20cyanide | In organic chemistry, an acyl cyanide is a functional group with the formula and structure . It consists of an acyl group () attached to cyanide (). Examples include acetyl cyanide, formyl cyanide, and oxalyl dicyanide. Acyl cyanides are reagents in organic synthesis.
Synthesis
Classically acyl cyanides are produced by the salt metathesis reaction of acyl chlorides with sodium cyanide:
Alternatively, they can be produced by dehydration of acyl aldoximes:
Acetyl cyanide is also prepared by hydrocyanation of ketene:
Reactions
They are mild acylating agents. With aqueous base, acyl cyanides break down to cyanide and the carboxylate:
With azides, acyl cyanides undergo the click reaction to give acyl tetrazoles.
References
Functional groups
Organic compounds | Acyl cyanide | [
"Chemistry"
] | 200 | [
"Organic compounds",
"Functional groups"
] |
68,063,156 | https://en.wikipedia.org/wiki/Halococcaceae | Halococcaceae is a family of halophilic and mostly chemoorganotrophic archaea within the order Halobacteriales. The type genus of this family is Halococcus. Its biochemical characteristics are the same as the order Halobacteriales.
The name Halococcaceae is derived from the Latin term Halococcus, referring to the type genus of the family and the suffix "-ceae", an ending used to denote a family. Together, Halococcaceae refers to a family whose nomenclatural type is the genus Halococcus.
Current Taxonomy and Molecular Signatures
As of 2021, Halococcaceae contains a single validly published genus, Halococcus. This family can be molecularly distinguished from other Halobacteria by the presence of 23 conserved signature proteins (CSPs) and nine conserved signature indels (CSIs) present in the following proteins: DNA gyrase subunit B, chaperone protein DnaK, HAD-superfamily hydrolase, glycosyltransferase, 2-Succinyl-6-hydroxy-2,4-cyclohexadiene-1-carboxylate synthase, iron-regulated ABC transporter, glycine dehydrogenase subunit 2, GMP synthase and a hypothetical protein.
References
Halobacteria
Taxa described in 2016
Monotypic archaea taxa | Halococcaceae | [
"Biology"
] | 290 | [
"Archaea",
"Archaea stubs"
] |
68,063,646 | https://en.wikipedia.org/wiki/Theta%20Mensae | θ Mensae, Latinized to Theta Mensae, is a star located in the southern circumpolar constellation Mensa. It has an apparent magnitude of 5.45, making it faintly visible to the naked eye if viewed under ideal conditions. Based on parallax measurements from Gaia Data Release 3, the object is estimated to be 385 light years distant. The value is horribly constrained, but it appears to be receding with a heliocentric radial velocity of .
This is a solitary, B-type main-sequence star with a stellar classification of B9.5 V. Houk and Cowley (1975) give it a class of B9.5/A0 III/IV, indicating that it is a B9.5-A0 star with the blended luminosity class of a giant star and a subgiant. Nevertheless, Theta Mensae has 2.87 times the Sun’s mass and a enlarged radius of . It radiates 124 solar luminosities from its photosphere and it has an effective temperature of 9,938 K, giving it a bluish-white hue. It is estimated to be 266 million years old, having completed 85.2% of its main sequence lifetime, hence the large radius. Like most hot stars, it spins rapidly, having a projected rotational velocity of .
Data from the Transiting Exoplanet Survey Satellite suggests that Theta Mensae may be a slowly pulsating B-type star plus a variable star with rotation modulations
References
54239
2689
Mensae, Theta
PD-79 00238
Mensa (constellation)
033384
B-type main-sequence stars
Mensae, 42 | Theta Mensae | [
"Astronomy"
] | 353 | [
"Mensa (constellation)",
"Constellations"
] |
68,064,150 | https://en.wikipedia.org/wiki/NGC%204643 | NGC 4643 is a lenticular galaxy located in the constellation Virgo. It is a member of the NGC 4753 Group of galaxies, which is a member of the Virgo II Groups, a series of galaxies and galaxy clusters strung out from the southern edge of the Virgo Supercluster.
References
External links
Virgo (constellation)
4643
Barred lenticular galaxies
042797 | NGC 4643 | [
"Astronomy"
] | 81 | [
"Virgo (constellation)",
"Constellations"
] |
68,064,532 | https://en.wikipedia.org/wiki/HD%2071863 | HD 71863 (HR 3346) is a solitary star in the southern circumpolar constellation Volans. It is faintly visible to the naked eye with an apparent magnitude of 5.94 and is located 408 light-years away based on parallax measurements. However, it is receding with a radial velocity of .
HD 71863 has a classification of G8/K0 III — intermediate between a G8 and K0 giant star. It has 2.65 times the mass of the Sun but has expanded to 11 times it's girth. It shines at 72 times the luminosity of the Sun and rotates slowly, with a projected rotational velocity of . With an effective temperature of , it has a yellowish-orange hue. HD 71863 metallicity – elements heavier than helium – is at solar level.
HD 71863 is located near a group of stars moving with a Carinae, but is just moving with them by coincidence, and has no relation to the group.
References
71863
3346
41321
Durchmusterung objects
G-type giants
K-type giants
Volans
Volantis, 28 | HD 71863 | [
"Astronomy"
] | 239 | [
"Volans",
"Constellations"
] |
68,065,196 | https://en.wikipedia.org/wiki/Percolation%20surface%20critical%20behavior | Percolation surface critical behavior concerns the influence of surfaces on the critical behavior of percolation.
Background
Percolation is the study of connectivity in random systems, such as electrical conductivity in random conductor/insulator systems, fluid flow in porous media, gelation in polymer systems, etc. At a critical fraction of connectivity or porosity, long-range connectivity can take place, leading to long-range flow. The point where that connectivity takes place is called the percolation threshold, and considerable amount of work has been undertaken in finding those critical values for systems of various geometries, and the mathematical behavior of observables near that point. This leads to the study of critical behavior and the percolation critical exponents. These exponents allow one to describe the behavior as the threshold is approached.
The behavior of the percolating network near a surface will be different from that in the main part of a system, called the "bulk." For example, exact at the percolation threshold, the percolating network in the system is a fractal with large voids and a ramified structure. The surface interrupts this structure, so the percolating cluster is less likely to come in contact to the surface. As an example, consider a lattice system of bond percolation (percolation along the bonds or edges of the lattice). If the lattice is cubic in nature, and is the probability that a bond is occupied (conducting), then the percolation threshold is known to be . At the surface, the lattice becomes a simple square lattice, where the bond threshold is simply 1/2. Therefore, when the bulk of the system is at its threshold, the surface is way below its threshold, and the only way to have long-range connections along the surface is to have a path that goes from the surface to the bulk, conduction through the fractal percolation network, and then a path back to the surface again. This occurs with a different critical behavior as in the bulk, and is different from the critical behavior of a two-dimensional surface at its threshold.
In the most common model for surface critical behavior in percolation, all bonds are assigned with the same probability , and the behavior is studied at the bulk , with a value of 0.311608 in this case. In an other model for surface behavior, the surface bonds are made occupied with a different probability , while the bulk is kept at the normal bulk value. When is increased to a higher value, a new "special" critical point is reached , which has a different set of critical exponents.
Surface phase transitions
In percolation, we can choose to occupy the sites or bonds at the surface with a different probability to the bulk probability . Different surface phase transitions can then occur depending on the values of the bulk occupation probability and the surface occupation probability . The simplest case is the ordinary transition, which occurs when is at the critical probability for the bulk phase transition. Here both the bulk and the surface start percolating, regardless of the value of , since there will typically be a path connecting the surface boundaries through the percolating bulk. Then there is the surface transition, where the bulk probability is below the bulk threshold, but the surface probability is at the percolation threshold for percolation in one lower dimension (i.e. the dimension of the surface). Here the surface undergoes a percolation transition while the bulk remains disconnected. If we enter this region of the phase diagram where the surface is ordered while the bulk is disordered, and then increase the bulk probability, we eventually encounter the extraordinary transition, where the bulk undergoes a percolation transition with the surface already percolating. Finally, there is the special phase transition, which is an isolated point where the phase boundaries for the ordinary, special, and extraordinary transitions meet.
In general the different surface transitions will be in distinct surface universality classes, with different critical exponents. Given an exponent, say , we label the relevant exponent at the ordinary, surface, extraordinary, and special transitions by , , , and respectively.
surface percolation thresholds
Surface critical exponents
The probability that a surface sites connected to the infinite (percolating) cluster, for an infinite system and , is given by
with where is the bulk exponent for the order parameter.
As a function of the time in an epidemic process (or the chemical distance), we have at
with , where is the bulk dynamical exponent.
Scaling relations
The critical exponents the following scaling relations:
(Deng and Blöte)
See also
Percolation
Percolation theory
Percolation critical exponents
References
Percolation theory
Critical phenomena | Percolation surface critical behavior | [
"Physics",
"Chemistry",
"Materials_science",
"Mathematics"
] | 971 | [
"Physical phenomena",
"Phase transitions",
"Critical phenomena",
"Percolation theory",
"Combinatorics",
"Condensed matter physics",
"Statistical mechanics",
"Dynamical systems"
] |
68,065,349 | https://en.wikipedia.org/wiki/Salicornia%20pacifica | Salicornia pacifica, also known as pickleweed, sea asparagus, Pacific swampfire, or glasswort, is a species of low-growing perennial succulent halophyte in the genus Salicornia found in the Pacific coast of North America and California.
Description
S. pacifica grows as erect shrubs possessing a well-developed primary central root system with few or no adventitious roots. It tends to flower between July and November.
Distribution
The species is native to salt marshes and alkaline soils throughout coastal California. It is occasionally found in Alaska and the East Coast. It occurs below 100 meters (330 feet) elevation. The genus is distributed globally.
Ecology
Pickleweed is specially adapted to use saltwater as its main source of water. When the saltwater is taken up, the salt is removed and stored in specialized vacuoles in the terminal segments. As the vacuoles become full of brine, they turn red and drop off the plant, removing the salt. Although pickleweed can withstand short periods of flooding, it will die under prolonged immersion, as when the estuary mouth closes and the salt marsh floods.
Pickleweed is an important nesting habitat for migrating birds. It is also an important food source for the endangered salt marsh harvest mouse.
Uses
Pickleweed is edible and has a salty flavor.
Gallery
References
pacifica
Halophytes | Salicornia pacifica | [
"Chemistry"
] | 285 | [
"Halophytes",
"Salts"
] |
68,065,457 | https://en.wikipedia.org/wiki/Nickel%28III%29%20fluoride | Nickel(III) fluoride is the chemical compound with the formula NiF3. It is an ionic compound of nickel and fluorine.
Preparation
Nickel(III) fluoride can be prepared by the reaction of potassium hexafluoronickelate(IV) with arsenic pentafluoride in hydrofluoric acid.
References
Nickel compounds
Fluorides
Metal halides | Nickel(III) fluoride | [
"Chemistry"
] | 82 | [
"Inorganic compounds",
"Salts",
"Inorganic compound stubs",
"Metal halides",
"Fluorides"
] |
68,066,476 | https://en.wikipedia.org/wiki/Carbonate%20oxalate | The carbonate oxalates are mixed anion compounds that contain both carbonate (CO3) and oxalate (C2O4) anions. Most compounds incorporate large trivalent metal ions, such as the rare earth elements. Some carbonate oxalate compounds of variable composition are formed by heating oxalates.
Formation
One method to form carbonate oxalates is to heat a metal salt with ascorbic acid, which decomposes to oxalate and carbonate and combines with the metal.
Reactions
When heated, oxalate carbonates decompose to carbon monoxide and carbonates, which form oxides at higher temperatures.
List
References
Carbonates
Mixed anion compounds
Oxalates | Carbonate oxalate | [
"Physics",
"Chemistry"
] | 141 | [
"Ions",
"Matter",
"Mixed anion compounds"
] |
68,066,590 | https://en.wikipedia.org/wiki/Frank%20B.%20Mallory%20%28chemist%29 | Frank B. Mallory (March 17, 1933 - November 7, 2017) was a professor of organic chemistry at Bryn Mawr College. He was on faculty at Bryn Mawr for 54 years, the longest-serving faculty member in the school's history. His work focused on photochemistry, NMR spectroscopy, and solid-state chemistry. The Mallory reaction is an organic name reaction he discovered while a graduate student. Mallory's professional honors include a John Simon Guggenheim Memorial Foundation fellowship and a Sloan Research Fellowship.
References
Bryn Mawr College faculty
American organic chemists
Photochemists
1930s births
2017 deaths
Year of birth uncertain | Frank B. Mallory (chemist) | [
"Chemistry"
] | 127 | [
"Organic chemists",
"Photochemists",
"Physical chemists",
"American organic chemists"
] |
68,067,905 | https://en.wikipedia.org/wiki/Oxalate%20phosphate | The oxalate phosphates are chemical compounds containing oxalate and phosphate anions. They are also called oxalatophosphates or phosphate oxalates. Some oxalate-phosphate minerals found in bat guano deposits are known. Oxalate phosphates can form metal organic framework compounds.
Related compounds include the arsenate oxalates, and phosphite oxalates, oxalatomethylphosphonate, and potentially other oxalate phosphonates.
List
References
Oxalates
Phosphates
Mixed anion compounds | Oxalate phosphate | [
"Physics",
"Chemistry"
] | 116 | [
"Matter",
"Mixed anion compounds",
"Salts",
"Phosphates",
"Ions"
] |
68,069,906 | https://en.wikipedia.org/wiki/Hidden%20Disabilities%20Sunflower | Hidden Disabilities Sunflower is a British scheme and company created to help people with hidden disabilities navigate and find help in public places, by providing sunflower lanyards to provide for people with hidden disabilities to signal their need for extra help in public.
History
The scheme was created in 2016 by Gatwick Airport and various charities.
In April 2019, London North Eastern Railway became the first railway company to recognize the scheme. By July 2020, all British railway companies had adopted the sunflower lanyard scheme as a means for passengers to let staff members know they may need more assistance, and that they may be medically exempt from wearing a face covering.
The scheme has now been adopted by airports in the United States, including Tulsa International Airport and Central Illinois Regional Airport. It has now been adopted by airports in Australia, Bahamas, Belgium, Caribbean, Columbia, Croatia, Cyprus, Denmark, Germany, Iceland, Ireland, India, Italy, Japan, Lithuania, New Zealand, Peru, Poland, Singapore, Sweden, Turkey, The Netherlands, UAE, UK and USA.
In Hong Kong, it has been adopted by the HSBC Bank.
In July 2023, Brazil sanctioned Law No. 14,624, which recognizes the Hidden Disabilities Sunflower as the national symbol for hidden disabilities. This law amends the Brazilian Law for the (13.146/15) to provide for the use of the Sunflower lanyard by people with hidden disabilities.
Distribution
Sunflower lanyards and badges can be obtained for free at participating venues or purchased directly from the Hidden Disabilities Sunflower company website. Hidden Disabilities Sunflower have criticized the resale of their products at inflated costs, and the sale of counterfeit products on websites including Amazon and eBay.
Usage
The sunflower lanyards are intended to let staff members know that the wearer has a hidden disability and as a result may take longer or need extra assistance. Staff members are trained to spot the lanyards and help the wearer.
During the COVID-19 pandemic, concerns were raised that the lanyards were being abused by non-disabled people for the purposes of avoiding wearing a face covering. Such usage has been criticized by Hidden Disabilities Sunflower, who have stated that only people who consider themselves to have a hidden disability (whether diagnosed or not) should wear the lanyard.
In 2024, Lego announced that they have partnered with Hidden Disabilities Sunflower to produce minifigures with the sunflower lanyard.
References
External links
Official website
Disability in the United Kingdom
Disability culture
Accessible transportation | Hidden Disabilities Sunflower | [
"Physics"
] | 515 | [
"Physical systems",
"Transport",
"Accessible transportation"
] |
68,070,972 | https://en.wikipedia.org/wiki/Straight%20Outta%20Nowhere%3A%20Scooby-Doo%21%20Meets%20Courage%20the%20Cowardly%20Dog | Straight Outta Nowhere: Scooby-Doo! Meets Courage the Cowardly Dog is a 2021 American animated mystery film produced by Warner Bros. Animation, and is the 36th entry in the direct-to-video series of Scooby-Doo films. The film also serves as a crossover between Scooby-Doo and the Cartoon Network show Courage the Cowardly Dog. The film was released on DVD and Digital on September 14, 2021.
Plot
While unmasking a bank-robbing clown, Scooby-Doo hears a strange noise and is driven to dance before he runs off. Meanwhile, Courage appears to be having the same problem, though Muriel and Eustace don't seem to notice. The gang rushes after Scooby, only to find that they have ended up in Nowhere, Kansas, where many hostile cicadas are surrounding Courage and Scooby. After they killed the cicadas, Muriel calls them over to the Bagge household, where they properly meet her and Eustace.
Both the Scooby gang and the Bagge family are invited to dinner with the Mayor of Nowhere. On the way there, Scooby and Courage are attacked by a giant Cicada Queen, resulting in the destruction of Eustace's truck. Arriving at the Mayor of Nowhere's mansion, they are offered a tour of an attached museum detailing Nowhere's bizarre history of attracting weirdness to the town. Shaggy, Scooby and Courage look for something to eat, while Eustace heads back to the Bagge residence. Shaggy, Scooby and Courage are attacked by the Cicada Queen, whose brood knocks Fred, Daphne, Velma and Muriel into a hidden cave. There, they discover a strange machine randomly sending out cellphone calls; Shaggy, Scooby and Courage destroy it while escaping the Cicada Queen. At the Bagge residence, Eustace makes a Shaggy-esque sandwich when he gets guests at the door. Each visitor is one of the call recipients and they leave large amounts of money.
Attempting to return to the Bagge residence to unravel the mystery, the group is once again attacked by the Cicada Queen, which kidnaps most of them, leaving only Scooby and Courage behind. Plugging Velma's personal tablet into Courage's computer, they discover that the cicada's unnatural size and every other strange encounter Courage dealt with was the result of a dark matter meteor, the one presumably to have wiped out the dinosaurs, which is buried under the spot where the Bagge residence is. Courage and Scooby retrieve the meteor and rescue the gang. Their attempt to escape is thwarted by the Cicada Queen, who takes the meteor and holds Muriel hostage, forcing Courage to face his fears and confront it. After a long battle, the Cicada Queen is trapped under scraps from the Bagge windmill.
The General and the Lieutenant soon arrive to apprehend the Cicada Queen, which is revealed to be a mech piloted by Katz and Le Quack. After discovering the meteor's existence, they teamed up to take over Nowhere's political facilities and to use the resources to dig up the meteor to hypnotize and rob several well-off locals, stashing it at the Bagge residence. When they learned that the Scooby gang was in the area, they used the meteor to brainwash the local cicada population to scare them off in an attempt to "up their game". The General attempts to secure the meteor to be used ostensibly as a weapon, but at Courage's suggestion, it is turned into a disco ball so the group can celebrate.
Voice cast
Production
John R. Dilworth, the original creator of Courage the Cowardly Dog, was not involved with the film's production. Marty Grabstein and Thea White reprised their roles as Courage and Muriel Bagge, while voice actor Jeff Bergman voiced Eustace Bagge, taking over from actors Lionel Wilson and Arthur Anderson, due to the latter dying in 2003 and 2016, respectively. Bergman had previously voiced Eustace prior in a commercial advert for Cartoon Network's 20th anniversary in 2012.
The crossover marks the final acting credit of Thea White, who died during surgery on July 30, 2021, due to liver cancer, and the film was dedicated to her memory.
Release
The film was released on DVD and Digital HD by Warner Bros. Home Entertainment on September 14, 2021.
Reception
Dillon Gonzales, writing for Geek Vibes Nation, gave the film a positive review, saying "there are moments that feel a bit padded to justify a feature-length effort, but it is easy to give them a pass as you enjoy spending time with these characters". Becky O'Brien of Cinelinx also gave a positive review, saying the film "exceeded all of my expectations. This is a movie fans of both series will enjoy. It is literally a love letter to everything that makes both Scooby-Doo and Courage the Cowardly Dog fun to watch".
Common Sense Media gave the film 2 out of 5 stars.
Boca do Inferno said, "it's worth it for the opportunity to see them again on stage, fighting monsters with fear, sympathy and a lot of voracity."
References
External links
2021 American animated direct-to-video films
2020s children's animated films
2020s supernatural films
2021 adventure films
2021 comedy films
2021 films
Animated films based on animated series
American children's animated adventure films
American children's animated comedy films
American children's animated mystery films
American comedy horror films
American monster movies
American mystery films
Animated crossover films
Animated films about dogs
Animated films about insects
Courage the Cowardly Dog
2020s English-language films
Films about curses
Films based on television series
Films directed by Cecilia Aranovich
Films produced by Sam Register
Animated films set in Kansas
Hanna-Barbera animated films
Scooby-Doo direct-to-video animated films
Warner Bros. Animation animated films
Warner Bros. direct-to-video animated films
English-language adventure films | Straight Outta Nowhere: Scooby-Doo! Meets Courage the Cowardly Dog | [
"Physics",
"Astronomy"
] | 1,240 | [
"Dark matter",
"Unsolved problems in astronomy",
"Concepts in astronomy",
"Unsolved problems in physics",
"Exotic matter",
"Physics beyond the Standard Model",
"Matter"
] |
68,071,223 | https://en.wikipedia.org/wiki/Malayalam%20numerals | Malayalam numerals are the numeral system of the Malayalam script used by Malayalam in Kerala. It is one of several Indian numeral systems. This system is archaic and nowadays the Hindu–Arabic numeral system is used commonly. However it is still found in many documents of cultural or historical importance.
Base numbers
Below is a list of Malayalam numerals with their Hindu–Arabic equivalents as well as their respective Malayalam translations and transliterations.
Originally, a number like "11" would have been written as "൰൧" and not "൧൧" to match the Malayalam word for 11 and "10,00,000" as "൰൱൲" similar to the Tamil numeral system. Later on this system got reformed to be more similar to the Hindu–Arabic numerals so 10,00,000 in the reformed numerals it would be .
Old system
Suppose the number is "2013". It is read in Malayalam as "രണ്ടായിരത്തി പതിമൂന്ന്" (raṇḍāyiratti padimūnnŭ). It is split into:
രണ്ട് (raṇḍŭ) : 2 - ൨
ആയിരം (āyiram) : 1000 - ൲
പത്ത് (pattŭ) : 10 - ൰
മൂന്ന് (mūnnŭ) : 3 - ൩
Combine them together to get the Malayalam number ൨൲൰൩.
Fractions
In Malayalam you can transcribe any fraction by affixing () after the denominator followed by the numerator, so a fraction like would be read as () 'out of ten, seven' but fractions like and have distinct names (, , ) and () 'half quarter'.
References
Malayalam language
Numerals | Malayalam numerals | [
"Mathematics"
] | 330 | [
"Numeral systems",
"Numerals"
] |
63,769,835 | https://en.wikipedia.org/wiki/Zombie%20satellite | A zombie satellite is a satellite that begins communicating again after an extended period of inactivity. It is a type of space debris, which describes all defunct human-made objects in outer space. At the end of their service life, the majority of satellites suffer from orbital decay and are destroyed by the heat of atmospheric entry. Zombie satellites, however, maintain a stable orbit but are either partially or completely inoperable, preventing operators from communicating with them consistently.
History
Transit 5B-5
One of the oldest known zombie satellites is Transit 5B-5.
It was launched in 1965 as part of the Transit system, one of the first satellite navigation systems.
Transit 5B-5 is solar powered and still in a stable polar orbit, though operators are unable to control it.
LES-1
LES-1, also known as Lincoln Experimental Satellite 1, was a communications satellite launched by the United States Air Force on February 11, 1965, to study the use of Super High Frequency radio transmissions. It never achieved optimal orbit and was out of contact for more than 40 years before spontaneously resuming transmissions in 2012.
AMSAT-OSCAR 7
AMSAT-OSCAR 7 is an amateur-radio communications satellite which was launched into Low Earth Orbit on November 15, 1974, and remained operational until a battery failure in 1981. Then after 21 years of apparent silence, the satellite was heard again on June 21, 2002 – 27 years after launch.
Galaxy 15
Galaxy 15 is a U.S. telecommunications satellite launched in 2005. In April 2010, only five years into a planned 15-year mission, its operator, Intelsat, lost control of the satellite and it drifted out of its orbital slot. Several months later, on December 27, 2010, the satellite rebooted itself and began responding to commands again. Intelsat re-positioned it back to its original orbital slot in April 2011.
IMAGE
Launched in 2000, IMAGE (Imager for Magnetopause-to-Aurora Global Exploration), a NASA spacecraft studying the Earth's magnetosphere, unexpectedly ceased operations in December 2005. It was a zombie satellite until Scott Tilley, an amateur radio operator living in Canada tracked it down in January 2018. On February 25, contact with IMAGE was again lost. It was reestablished in March but lost again in August. NASA is currently evaluating a recovery mission.
LES-5
On March 24, 2020, contact with another lost Lincoln Experimental Satellite, LES-5, was made by Scott Tilley. The satellite is only in operation when its solar panels are receiving sunlight.
See also
Space debris
Skylab 4
Space Liability Convention
List of spaceflight-related accidents and incidents
Laser broom
Kessler syndrome
References
Satellites
Space debris | Zombie satellite | [
"Astronomy",
"Technology"
] | 542 | [
"Satellites",
"Space debris",
"Outer space"
] |
63,770,785 | https://en.wikipedia.org/wiki/Construction%20robots | Construction robots are a subset of industrial robots used for building and infrastructure construction at site. Despite being traditionally slow to adopt new technologies, 55% of construction companies in the United States, Europe, and China now say they use robots on job sites. Most of the robots working on jobsites today are designed to remove strains on humans, e.g., excavating and lifting heavy objects. Robots that survey and layout markers, tie rebar, and install drywall are also now on the market.
Other robots are being developed to perform tasks such as finishing the exterior, steel placement, construction of masonry wall, reinforcement concrete, etc. The main challenge to use robots in site is due to limitation in workspace.
Features
General features include:
It must be able to move.
It must be able to handle components of variable size and weight.
It must be able to adjust with changing environment.
It must be able to interact with its surroundings.
It must be able to perform multiple tasks.
Capabilities
Construction robots have been tested to carry out the followings:
Building walls
Monitor the construction progress
Inspection robots are used to investigate the infrastructures, mainly at dangerous locations
Notable construction by robots
30 storied Rail City Building at Yokohama, Japan was constructed by an automated system.
Concrete floor finish robot was used by Kajima and Tokimec companies in Japan.
Obayashi Corporation in Japan has developed and used a system to lay concrete layers in dam construction.
Social impact
Use of the construction robots in the USA is rare, mainly due to opposition from labour unions. However, in Japan, these robots are taken positively.
See also
Industrial robots
References
Robotics | Construction robots | [
"Engineering"
] | 330 | [
"Robotics",
"Automation"
] |
63,770,815 | https://en.wikipedia.org/wiki/Duplodnaviria | Duplodnaviria is a realm of viruses that includes all double-stranded DNA viruses that encode the HK97 fold major capsid protein. The HK97 fold major capsid protein (HK97 MCP) is the primary component of the viral capsid, which stores the viral deoxyribonucleic acid (DNA). Viruses in the realm also share a number of other characteristics, such as an icosahedral capsid, an opening in the viral capsid called a portal, a protease enzyme that empties the inside of the capsid prior to DNA packaging, and a terminase enzyme that packages viral DNA into the capsid.
Duplodnaviria was established in 2019 based on the shared characteristics of viruses in the realm. There are two groups of viruses in Duplodnaviria: tailed bacteriophages of the order Caudovirales, which infect prokaryotes, and herpesviruses of the order Herpesvirales, which infect animals. Tailed bacteriophages are very diverse and ubiquitous worldwide, and they may be the oldest lineage of viruses. Herpesviruses either share a common ancestor with tailed bacteriophages or are a breakaway group from within Caudovirales.
Tailed bacteriophages are important in marine ecology by recycling nutrients in organic material from their hosts and are the focus of much research, and herpesviruses are associated with a variety of diseases in animals, including humans. A common feature among viruses in Duplodnaviria is that many are able to persist in their host for long periods of time without replicating while still being able to resurface in the future. Examples of this include the herpes simplex virus, which causes recurring infections, and the varicella zoster virus, which initially causes chickenpox early in life then shingles later in life.
Etymology
The name Duplodnaviria is a portmanteau of duplo, the Latin word for double, dna, from deoxyribonucleic acid (DNA), referencing that all members of the realm at founding had double-stranded DNA genomes, and -viria, which is the suffix used for virus realms. Duplodnaviria is monotypic, having only one kingdom, Heunggongvirae, so both the realm and kingdom have the same definition. Heunggongvirae takes the first part of its name from Cantonese 香港 [Hēunggóng], meaning and approximately pronounced "Hong Kong", which is a reference to Escherichia virus HK97, the founding member of the HK97 (Hong Kong 97) fold MCP viruses, and the suffix -virae, which is the suffix used for virus kingdoms.
Characteristics
All viruses in Duplodnaviria contain a distinct icosahedral capsid that is composed of a major capsid protein that contains a unique folded structure, called the HK97 fold, named after the folded structure of the MCP of the bacteriophage species Escherichia virus HK97. Despite having significant variation across Duplodnaviria, the base structure of the protein is retained among all species in the realm. Other shared proteins that involve the structure and assembly of capsids include a portal protein that the opening of the capsid is made of, a protease that empties the capsid before DNA is inserted, and the terminase enzyme that inserts the DNA into the capsid.
After HK97 MCPs have been synthesized by the host cell's ribosomes, the viral capsid is assembled from them with the proteins bonding to each other. The inside of the capsid contains scaffold proteins that guide the geometric construction of the capsid. In the absence of separate scaffolding proteins, the delta domain of HK97 MCP, which faces toward the inside of the capsid, acts as a scaffold protein.
A cylindrical opening in the capsid, called a portal, that serves as the entrance and exit for viral DNA is created with portal proteins at one of the 12 vertices of the capsid. The scaffold protein, which may be the delta domain of HK97 MCP, is removed from the inside of the capsid by the capsid maturation protease, which may also be a part of the scaffolding, breaking it and itself down to smaller molecules in a process called proteolysis that leaves the inside of the capsid empty.
At the same time as capsid assembly, replication of the viral DNA occurs, creating concatemers, long molecules of DNA containing numerous copies of the viral genome. The enzyme terminase, made of two subunits, large and small, finds the viral DNA inside of the cell via the small subunit, cuts the concatemers, and creates the termini, or endings, of the genomes. Terminase recognizes a packaging signal in the genome and cuts the nucleic acid, creating a free end that it binds to.
The terminase, now bound to the concatemer, attaches itself to the capsid portal and begins translocating the DNA from outside the capsid to the inside, using energy generated from ATP hydrolysis by the large subunit. As more DNA is inserted into the capsid, the capsid expands in size, becomes thinner, and its surface becomes flatter and more angular. Once the genome is completely inside, terminase cuts the concatemer again, completing packaging. Terminase then detaches itself from the portal and proceeds to repeat this process until all genomes in the concatemer have been packaged.
For tailed bacteriophages, after DNA packaging, the tail of the virion, which was assembled separately, is attached to the capsid, commonly called the "head" of tailed bacteriophages, at the portal. Tailed bacteriophages also sometimes have "decoration" proteins that attach to the capsid's surface in order to reinforce the capsid's structure. After the virion is fully assembled inside the host cell, it leaves the cell. Tailed bacteriophages leave the cell via lysis, rupturing of the cell membrane, that causes cell death, and herpesviruses leave by budding from the host cell membrane, using the membrane as a viral envelope that covers the capsid.
Phylogenetics
Tailed bacteriophages are potentially the oldest lineage of viruses in the world because they are ubiquitous worldwide, only infect prokaryotes, and have a high level of diversity. Their highly divergent virion structures may point to this or may indicate separate origins. The origin of Herpesvirales is unclear, but there are two likely scenarios. First, ancestral lineages of Caudoviricetes may have produced clades at various times that were capable of infecting eukaryotes, and the strong similarity that Herpesvirales has with Caudoviricetes may indicate that it is a more recent descendant of one such lineage. The second likely scenario is that Herpesvirales is a breakaway clade from within Caudoviricetes, which is supported by one of the Caudoviricetes subfamilies, Tevenvirinae, showing a relatively high genetic relation to herpesviruses based on certain protein amino acid sequences. It has been suggested that Duplodnaviria predates the last universal common ancestor (LUCA) of cellular life and that viruses in the realm were present in the LUCA.
The HK97 fold MCP appears to have been created from a DUF1884 protein family domain that was inserted into a strand-helix-strand-strand (SHS2) fold protein related to the dodecin protein family. The resulting protein was then acquired by a mobile genetic element, leading to the creation of duplodnaviruses. Outside of Duplodnaviria, an HK97-like fold is only found in encapsulins, a type of prokaryotic nanocompartment that encapsulate a variety of cargo proteins related to the oxidative stress response. Encapsulins assemble into icosahedrons like the capsids of duplodnaviruses, but the HK97 MCP in viruses is much more divergent and widespread than in encapsulins, which form a narrow monophyletic clade. As such, it is more likely that encapsulins are derived from viruses than vice versa. Archaea of the phylum Thermoproteota (formerly Crenarchaeota) contain encapsulins but are not known to be infected by tailed bacteriophages though, so the relation between encapsulins and Duplodnaviria remains unresolved.
The ATPase subunit of Duplodnaviria terminases that generates energy for packaging viral DNA has the same general structural design of the P-loop fold as the packaging ATPases of double jelly roll fold MCP viruses in the realm Varidnaviria but are otherwise not directly related to each other. While viruses in Duplodnaviria make use of the HK97 fold for their major capsid proteins, the major capsid proteins of viruses in Varidnaviria instead are marked by single or double vertical jelly roll folds.
Classification
Duplodnaviria contains only one kingdom, and this kingdom is subdivided into two phyla. This taxonomy can be visualized as follows:
Realm: Duplodnaviria
Kingdom: Heunggongvirae
Phylum: Peploviricota
Class: Herviviricetes
Order: Herpesvirales – the herpesviruses, which infect animals (eukaryotes)
Phylum: Uroviricota
Class: Caudoviricetes – the tailed bacteriophages, which infect archaea and bacteria (prokaryotes)
As all viruses in the realm are double-stranded DNA (dsDNA) viruses, the realm belongs to Group I: dsDNA viruses of Baltimore classification, a classification system based on a virus's manner of messenger RNA (mRNA) production, often used alongside standard virus taxonomy, which is based on evolutionary history. Realms are the highest level of taxonomy used for viruses and Duplodnaviria is one of six, the other five being Adnaviria,Monodnaviria, Riboviria, Ribozyviria and Varidnaviria.
Interactions with hosts
Viral shunt
Tailed bacteriophages are ubiquitous worldwide and are a major cause of death among prokaryotes. Infection may lead to cell death via lysis, the rupturing of the cell membrane. As a result of lysis, organic material from the killed prokaryotes is released into the environment, contributing to a process called viral shunt. Tailed bacteriophages shunt nutrients from organic material away from higher trophic levels so that they can be consumed by organisms in lower trophic levels, which has the effects of recycling nutrients and promoting increased diversity among marine life.
Disease
Herpesviruses are associated with a wide range of diseases in their hosts, including a respiratory tract illness in chickens, a respiratory and reproductive illness in cattle, and tumors in sea turtles. In humans, herpesviruses usually cause various epithelial diseases such as herpes simplex, chickenpox and shingles, and Kaposi's sarcoma. Initial infection causes acute symptoms and leads to lifelong infection via latency. Herpesviruses may emerge from their latency to cause illnesses, which may have severe symptoms such as encephalitis and pneumonia.
Latency
Viruses in Duplodnaviria have two different types of replication cycles, called the lytic cycle, whereby infection leads directly to virion formation and exit from the host cell, and the lysogenic cycle, whereby a latent infection retains the viral DNA inside of the host cell without virion formation, either as an episome or via integration into the host cell's DNA, with the possibility of returning to the lytic cycle in the future. Viruses that can replicate through the lysogenic cycle are called temperate or lysogenic viruses. Tailed bacteriophages vary in their temperateness, whereas all herpesviruses are temperate and able to avoid detection by the host's immune system, causing lifelong infections.
History
Tailed bacteriophages were discovered independently by Frederick Twort in 1915 and Félix d'Hérelle in 1917, and they have been the focus of much research since then. Diseases in humans caused by herpesviruses have been recognized for much of recorded history, and person-to-person transmission of the herpes simplex virus, the first herpesvirus discovered, was first recognized in 1893 by Émile Vidal.
Over time, the two groups were increasingly found to share many characteristics, and their genetic relation was formalized with the establishment of Duplodnaviria in 2019. The creation of the kingdom, phyla, and classes of the realm in the same year has also created a framework to more easily allow major reorganization of Caudovirales, which is growing in size significantly and which may require tailed bacteriophages to be promoted to the rank of class or higher.
See also
List of higher virus taxa
References
Further reading
Viruses
Virus realms | Duplodnaviria | [
"Biology"
] | 2,789 | [
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,770,837 | https://en.wikipedia.org/wiki/Sequences%20%28book%29 | Sequences is a mathematical monograph on integer sequences. It was written by Heini Halberstam and Klaus Roth, published in 1966 by the Clarendon Press, and republished in 1983 with minor corrections by Springer-Verlag. Although planned to be part of a two-volume set, the second volume was never published.
Topics
The book has five chapters, each largely self-contained and loosely organized around different techniques used to solve problems in this area, with an appendix on the background material in number theory needed for reading the book. Rather than being concerned with specific sequences such as the prime numbers or square numbers, its topic is the mathematical theory of sequences in general.
The first chapter considers the natural density of sequences, and related concepts such as the Schnirelmann density. It proves theorems on the density of sumsets of sequences, including Mann's theorem that the Schnirelmann density of a sumset is at least the sum of the Schnirelmann densities and Kneser's theorem on the structure of sequences whose lower asymptotic density is subadditive. It studies essential components, sequences that when added to another sequence of Schnirelmann density between zero and one, increase their density, proves that additive bases are essential components, and gives examples of essential components that are not additive bases.
The second chapter concerns the number of representations of the integers as sums of a given number of elements from a given sequence, and includes the Erdős–Fuchs theorem according to which this number of representations cannot be close to a linear function. The third chapter continues the study of numbers of representations, using the probabilistic method; it includes the theorem that there exists an additive basis of order two whose number of representations is logarithmic, later strengthened to all orders in the Erdős–Tetali theorem.
After a chapter on sieve theory and the large sieve (unfortunately missing significant developments that happened soon after the book's publication), the final chapter concerns primitive sequences of integers, sequences like the prime numbers in which no element is divisible by another. It includes Behrend's theorem that such a sequence must have logarithmic density zero, and the seemingly-contradictory construction by Abram Samoilovitch Besicovitch of primitive sequences with natural density close to 1/2. It also discusses the sequences that contain all integer multiples of their members, the Davenport–Erdős theorem according to which the lower natural and logarithmic density exist and are equal for such sequences, and a related construction of Besicovitch of a sequence of multiples that has no natural density.
Audience and reception
This book is aimed at other mathematicians and students of mathematics; it is not suitable for a general audience. However, reviewer J. W. S. Cassels suggests that it could be accessible to advanced undergraduates in mathematics.
Reviewer E. M. Wright notes the book's "accurate scholarship", "most readable exposition", and "fascinating topics". Reviewer Marvin Knopp describes the book as "masterly", and as the first book to overview additive combinatorics. Similarly, although Cassels notes the existence of material on additive combinatorics in the books Additive Zahlentheorie (Ostmann, 1956) and Addition Theorems (Mann, 1965), he calls this "the first connected account" of the area, and reviewer Harold Stark notes that much of material covered by the book is "unique in book form". Knopp also praises the book for, in many cases, correcting errors or deficiencies in the original sources that it surveys. Reviewer Harold Stark writes that the book "should be a standard reference in this area for years to come".
References
Additive combinatorics
Integer sequences
Mathematics books
1966 non-fiction books
1983 non-fiction books
Clarendon Press books | Sequences (book) | [
"Mathematics"
] | 794 | [
"Sequences and series",
"Integer sequences",
"Mathematical structures",
"Recreational mathematics",
"Additive combinatorics",
"Mathematical objects",
"Combinatorics",
"Numbers",
"Number theory"
] |
63,770,854 | https://en.wikipedia.org/wiki/Monodnaviria | Monodnaviria is a realm of viruses that includes all single-stranded DNA viruses that encode an endonuclease of the HUH superfamily that initiates rolling circle replication of the circular viral genome. Viruses descended from such viruses are also included in the realm, including certain linear single-stranded DNA (ssDNA) viruses and circular double-stranded DNA (dsDNA) viruses. These atypical members typically replicate through means other than rolling circle replication.
Monodnaviria was established in 2019 and contains four kingdoms: Loebvirae, Sangervirae, Trapavirae, and Shotokuvirae. Viruses in the first three kingdoms infect prokaryotes, and viruses in Shotokuvirae infect eukaryotes and include the atypical members of the realm. Viruses in Monodnaviria appear to have come into existence independently multiple times from circular bacterial and archaeal plasmids that encode the HUH endonuclease. Eukaryotic viruses in the realm appear to have come into existence multiple times via genetic recombination events that merged deoxyribonucleic acid (DNA) from the aforementioned plasmids with capsid proteins of certain RNA viruses. Most identified ssDNA viruses belong to Monodnaviria.
The prototypic members of the realm are often called CRESS-DNA viruses. CRESS-DNA viruses are associated with a wide range of diseases, including diseases in economically important crops and a variety of diseases in animals. The atypical members of the realm include papillomaviruses and polyomaviruses, which are known to cause various cancers. Members of Monodnaviria are also known to frequently become integrated into the DNA of their hosts as well as experience a relatively high rate of genetic mutations and recombinations.
Etymology
Monodnaviria is a portmanteau of mono, from Greek μόνος [mónos], meaning single, DNA from deoxyribonucleic acid (DNA), referencing single-stranded DNA, and the suffix -viria, which is the suffix used for virus realms. The prototypic members of Monodnaviria are often called CRESS-DNA, or CRESS DNA, viruses, which stands for "circular Rep-encoding ssDNA" viruses.
Characteristics
Endonuclease-initiated replication
All prototypical viruses in Monodnaviria encode an endonuclease of the HUH superfamily. Endonucleases are enzymes that can cleave phosphodiester bonds within a polynucleotide chain. HUH, or HuH, endonucleases are endonucleases that contain a HUH motif made of two histidine residues separated by a bulky hydrophobic residue and a Y motif that contains one or two tyrosine residues. The HUH endonuclease of ssDNA viruses is often called the replication initiation protein, or simply Rep, because its cleavage of a specific site in the viral genome initiates replication.
Once the viral ssDNA is inside of the host cell, it is replicated by the host cell's DNA polymerase to produce a double-stranded form of the viral genome. Rep then recognizes a short sequence on the 3'-end ("three prime end") at the origin of replication. Upstream {description needed} from the recognition site, Rep binds to the DNA and nicks the positive-sense strand, creating a nick {description needed} site. In doing so, Rep binds to the 5'-end (five prime end) via a tyrosine residue that covalently bonds {source for covalent bonds needed} to the phosphate backbone of DNA, creating a phosphotyrosine molecule that connects Rep to the viral DNA.
The 3'-end of the nicked strand remains as a free hydroxyl (OH) end that acts as a signal for the host DNA polymerase to replicate the genome. Replication commences at the 3'-OH end and is performed by extending the 3'-end of the positive strand using the negative strand as a template for replication. {refer to DNA replication} Synthesis of the new positive strand uses the negative strand as a template, and so synthesizes a newly connected strand of DNA which displaces the nicked positive strand to reform double-stranded DNA. The 3'-OH end of the displaced positive strand disrupts the original phosphotyrosine bond which releases and circularizes the displaced positive strand as its own circular copy of viral DNA. After one cycle of replicating the genome, Rep is able to recognize the newly replicated recognition site {recognize the recognition site?} on the reformed double-stranded viral DNA and nick it, which starts the whole process again.
Rep may nick the positive strand a second time, doing so with a second tyrosine residue, or a new Rep may nick the DNA. Multiple copies of the genome may be produced in a single strand. After the positive strand is completely detached from the negative strand and nicked, the 3'-OH end bonds to the phosphotyrosine of the 5'-end, creating a free circular ssDNA genome that usually is either converted into dsDNA for transcription or further replication or is packaged into newly constructed viral capsids. The replication process can be repeated numerous times on the same circular genome to produce many copies of the original viral genome.
Atypical members
While the prototypical viruses in Monodnaviria have circular ssDNA genomes and replicate via RCR, some have linear ssDNA genomes with different replication methods, including the families Parvoviridae and Bidnaviridae, assigned to the phylum Cossaviricota of the kingdom Shotokuvirae. Parvoviruses use rolling hairpin replication, in which the ends of the genome have hairpin loops that repeatedly unfold and refold during replication to change the direction of DNA synthesis to move back and forth along the genome, producing numerous copies of the genome in a continuous process. Individual genomes are then excised from this molecule by the HUH endonuclease. In place of the HUH endonuclease, bidnaviruses encode their own protein-primed DNA polymerase that replicates the genome, which is bipartite and packaged into two separate virions, instead of using the host cell's DNA polymerase for replication.
Additionally, some viruses in the realm are dsDNA viruses with circular genomes, including Polyomaviridae and Papillomaviridae, also assigned to the phylum Cossaviricota. Instead of replicating via RCR, these viruses use theta bidirectional DNA replication. This begins by unwinding the dsDNA at a site called the origin to separate the two DNA strands from each other. Two replication forks are established that move in opposite directions around the circular genome until they meet at the side opposite of the origin and replication is terminated.
Other characteristics
Apart from the aforementioned replication methods, ssDNA viruses in Monodnaviria share a number of other common characteristics. The capsids of ssDNA viruses, which store the viral DNA, are usually icosahedral in shape and composed of either one type of protein or, in the case of parvoviruses, multiple types of proteins. All ssDNA viruses that have had the structure of their capsid proteins analyzed in high resolution have shown to contain a single jelly roll fold in their folded structure.
Nearly all families of ssDNA viruses have a positive-sense genome, the sole exception being viruses in the family Anelloviridae, unassigned to a realm, which have a negative-sense genome. In any case, ssDNA viruses have their genomes converted to a dsDNA form prior to transcription, which creates the messenger RNA (mRNA) needed to produce viral proteins from ribosomal translation. CRESS-DNA viruses also have similar genome structures, genome lengths, and gene compositions.
Lastly, ssDNA viruses have a relatively high rate of genetic recombinations and substitution mutations. Genetic recombination, or mixture, of ssDNA genomes can occur between closely related viruses when a gene is replicated and transcribed at the same time, which may cause the host cell's DNA polymerases to switch DNA templates (negative strands) during the process, causing recombination. These recombinations usually occur in the negative strand and either outside of or at the peripheries of genes rather than toward the middle of genes.
The high substitution rate seen in ssDNA viruses is unusual since replication is performed primarily by the host cell's DNA polymerase, which contains proofreading mechanisms to prevent mutations. Substitutions in ssDNA viral genomes may occur because the viral DNA may become oxidatively damaged while the genome is inside the capsid. The prevalence of recombinations and substitutions among ssDNA viruses means that eukaryotic ssDNA viruses can emerge as threatening pathogens.
Phylogenetics
Comparison of genomes and phylogenetic analyses of the HUH endonucleases, superfamily 3 helicases (S3H), and capsid proteins of viruses in Monodnaviria have shown that they have multiple, chimeric origins. HUH endonucleases of CRESS-DNA viruses are most similar to those found in small, RCR bacterial and archael plasmids, extra-chromosomal DNA molecules inside bacteria and archaea, and appear to have evolved from them at least three times. HUH endonucleases of prokaryotic CRESS-DNA viruses seem to have originated from plasmid endonucleases that lacked the S3H domain, whereas eukaryotic CRESS-DNA viruses evolved from ones that had S3H domains.
The capsid proteins of eukaryotic CRESS-DNA viruses are most closely related those of various animal and plant positive-sense RNA viruses, which belong to the realm Riboviria. Because of this, eukaryotic CRESS-DNA viruses appear to have emerged multiple times from recombination events that merged DNA from bacterial and archaeal plasmids with complementary DNA (cDNA) copies of positive-sense RNA viruses. CRESS-DNA viruses therefore represent a notable instance of convergent evolution, whereby organisms that are not directly related evolve the same or similar traits.
Linear ssDNA viruses, specifically parvoviruses, in Monodnaviria are likely to have evolved from CRESS-DNA viruses via loss of the joining activity used by CRSS-DNA viruses to create circular genomes. In turn, the circular dsDNA viruses in Monodnaviria appear to have evolved from parvoviruses through inactivation of the endonuclease's HUH domain. The HUH domain then became a DNA-binding domain, changing these viruses' manner of replication to theta bidirectional replication. The capsid proteins of these circular dsDNA viruses are highly divergent, so it is unclear if they evolved from parvovirus capsid proteins or through other means. Bidnaviruses, which are linear ssDNA viruses, appear to have been created as a result of a parvovirus genome becoming integrated into the genome of a polinton, a type of self-replicating genomic DNA molecule, which replaced the HUH endonuclease with a polinton's DNA polymerase.
Classification
Monodnaviria has four kingdoms: Loebvirae, Sangervirae, Shotokuvirae, and Trapavirae. Loebvirae is monotypic down to the rank of order, and Sangervirae and Trapavirae are monotypic down to the rank of family. This taxonomy is described further as follows:
Kingdom: Loebvirae, which only infect bacteria, have filamentous or rod-shaped virions formed from an alpha-helical capsid protein, and encode a morphogenesis protein that is an ATPase of the FtsK-HerA superfamily
Phylum: Hofneiviricota
Class: Faserviricetes
Order: Tubulavirales
Family: Inoviridae
Family: Paulinoviridae
Family: Plectroviridae
Kingdom: Sangervirae, which only infect bacteria, have a capsid protein that contains a single jelly roll fold, and have a pilot protein required for transferring DNA across the cell envelope. The endonuclease of Sangervirae may also be a unifying trait since it appears to be monophyletic.
Phylum: Phixviricota
Class: Malgrandaviricetes
Order: Petitvirales
Family: Microviridae
Kingdom: Shotokuvirae, which encode an endonuclease containing an endonuclease domain, or a derivative of one, at the start of the protein's amino acid sequence and a superfamily 3 helicase domain at the end of the protein's amino acid sequence. Shotokuvirae notably includes linear ssDNA and circular dsDNA viruses, assigned to its phylum Cossaviricota, that are descended from CRESS-DNA viruses, assigned to the kingdom's other phylum Cressdnaviricota.
Phylum: Cossaviricota
Class: Mouviricetes
Order: Polivirales
Family: Bidnaviridae
Class: Papovaviricetes
Order: Sepolyvirales
Family: Polyomaviridae
Order: Zurhausenvirales
Family: Papillomaviridae
Class: Quintoviricetes
Order: Piccovirales
Family: Parvoviridae
Phylum: Cressdnaviricota
Class: Arfiviricetes
Order: Baphyvirales
Family: Bacilladnaviridae
Order: Cirlivirales
Family: Circoviridae
Family: Vilyaviridae
Order: Cremevirales
Family: Smacoviridae
Order: Mulpavirales
Family: Amesuviridae
Family: Metaxyviridae
Family: Nanoviridae
Order: Recrevirales
Family: Redondoviridae
Order: Rivendellvirales
Family: Naryaviridae
Order: Rohanvirales
Family: Nenyaviridae
Class: Repensiviricetes
Order: Geplafuvirales
Family: Geminiviridae
Family: Genomoviridae
Kingdom: Trapavirae, which only infect archaea and which have a viral envelope that contains a membrane fusion protein
Phylum: Saleviricota
Class: Huolimaviricetes
Order: Haloruvirales
Family: Pleolipoviridae
Monodnaviria includes the vast majority of identified ssDNA viruses, which are Group II: ssDNA viruses in the Baltimore classification system, which groups viruses together based on how they produce mRNA, often used alongside standard virus taxonomy, which is based on evolutionary history.. Of the 16 ssDNA virus families, three are not assigned to Monodnaviria, all three being unassigned to a realm: Anelloviridae, Finnlakeviridae, a proposed member of the realm Varidnaviria, and Spiraviridae. The dsDNA viruses in Monodnaviria are assigned to Baltimore Group I: dsDNA viruses. Realms are the highest level of taxonomy used for viruses and Monodnaviria is one of four, the other three being Duplodnaviria, Riboviria, and Varidnaviria.
Although Anelloviridae is currently unassigned to a realm, it is a potential member of Monodnaviria since it appears to be morphologically similar to circoviruses. It has been suggested that anelloviruses are essentially CRESS-DNA viruses with negative sense genomes, unlike the typical positive sense genomes.
Interactions with hosts
Disease
The eukaryotic CRESS-DNA viruses are associated with a variety of diseases. Plant viruses in the families Geminiviridae and Nanoviridae infect economically important crops, causing significant damage to agricultural productivity. Animal viruses in Circoviridae are associated with many diseases, including respiratory illness, intestinal illness, and reproductive problems. Bacilladnaviruses, which primarily infect diatoms, are thought to have a significant role in controlling algal blooms.
The atypical members of the realm are also associated with many widely known diseases. Parvoviruses are most widely known for causing a lethal infection in canids as well as causing fifth disease in humans. Papillomaviruses and polyomaviruses are known to cause different types of cancers and other diseases. A polyomavirus is responsible for Merkel-cell carcinoma, and papillomaviruses cause various genital and other cancers as well as warts.
Endogenization
The Rep protein lacks homologues in cellular organisms, so it can be searched for within an organism's genome to identify if viral DNA has become endogenized as part of the organism's genome. Among eukaryotes, endogenization is most often observed in plants, but it is also observed in animals, fungi, and various protozoans. Endogenization can occur through several means such as the integrase or transpose enzymes or by exploiting the host cell's recombination machinery.
Most endogenized ssDNA viruses are in non-coding regions of the organism's genome, but sometimes the viral genes are expressed, and the Rep protein may be used by the organism. Because viral DNA can become a part of an organism's genome, this represents an example of horizontal gene transfer between unrelated organisms that can be used to study evolutionary history. By comparing related organisms, it is possible to estimate the approximate age of ssDNA viruses. For example, comparison of animal genomes has shown that circoviruses and parvoviruses first integrated into their hosts' genomes at least 40–50 million years ago.
History
The earliest reference to a virus in Monodnaviria was made in a poem written in 752 by Japanese Empress Shotoku, describing a yellowing or vein clearing disease of Eupatorium plants that was likely caused by a geminivirus. Centuries later, a circovirus infection that caused balding in birds was observed in Australia in 1888, marking the first reference to ssDNA viruses in modern times. The first animal CRESS-DNA virus to be characterized was the porcine circovirus in 1974, and in 1977, the first genome of an ssDNA virus, the Bean golden mosaic virus, was detailed. Beginning in the 1970s, the families of related members in Monodnaviria began to be organized, Parvoviridae becoming the first ssDNA family recognized with additional families being continually discovered.
In recent years, analyses of viral DNA in various contexts such as fecal matter and marine sediments have shown that ssDNA viruses are widespread throughout nature, and the increased knowledge of their diversity has helped to greater understand their evolutionary history. The relation between CRESS-DNA viruses was resolved from 2015 to 2017, leading to the establishment of Monodnaviria in 2019 based on their shared relation, including viruses descended from them. Despite appearing to have polyphyletic origins, the similar genome structure, genome length, and gene compositions of CRESS-DNA viruses provided the justification to unite them under a realm.
See also
List of higher virus taxa
Notes
References
Further reading
Monodnaviria
Virus realms
Polyphyletic groups | Monodnaviria | [
"Biology"
] | 4,005 | [
"Phylogenetics",
"Polyphyletic groups"
] |
63,770,870 | https://en.wikipedia.org/wiki/Tubulavirales | Tubulavirales is an order of viruses.
Taxonomy
The following families are recognized:
Inoviridae
Paulinoviridae
Plectroviridae
References
Virus orders | Tubulavirales | [
"Biology"
] | 35 | [
"Virus stubs",
"Viruses"
] |
63,770,939 | https://en.wikipedia.org/wiki/Shotokuvirae | Shotokuvirae is a kingdom of viruses.
Nomenclature
The kingdom, Shotokuvirae, was named after Japan's Empress Shotoku (718-770 AD), who reigned over Japan twice, first as Empress Koken and later as Empress Shotoku, and who created the world's earliest written record of a plant virus disease, which was a poem to her followers about a geminivirus eupatorium yellow vein virus infection of a eupatorium plant, which she had described as having turned yellow.
Taxonomy
The following phyla are recognized:
Cossaviricota
Cressdnaviricota
References
Viruses | Shotokuvirae | [
"Biology"
] | 127 | [
"Virus stubs",
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,770,960 | https://en.wikipedia.org/wiki/Cossaviricota | Cossaviricota is a phylum of viruses.
Classes
The following classes are recognized:
Mouviricetes
Papovaviricetes
Quintoviricetes
References
Viruses | Cossaviricota | [
"Biology"
] | 40 | [
"Virus stubs",
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,770,985 | https://en.wikipedia.org/wiki/Papovaviricetes | Papovaviricetes is a class of viruses. The class shares the name of an abolished family, Papovaviridae, which was split in 1999 into the two families Papillomaviridae and Polyomaviridae. The class was established in 2019 and takes its name from the former family.
Orders
The following orders are recognized:
Sepolyvirales
Zurhausenvirales
See also
Bandicoot papillomatosis carcinomatosis virus
References
Viruses | Papovaviricetes | [
"Biology"
] | 99 | [
"Virus stubs",
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,771,045 | https://en.wikipedia.org/wiki/Cressdnaviricota | Cressdnaviricota is a phylum of viruses with small, circular single-stranded DNA genomes and encoding rolling circle replication-initiation proteins with the N-terminal HUH endonuclease and C-terminal superfamily 3 helicase domains. While the replication-associated proteins are homologous among viruses within the phylum, the capsid proteins are very diverse and have presumably been acquired from RNA viruses on multiple independent occasions. Nevertheless, all cressdnaviruses for which structural information is available appear to contain the jelly-roll fold.
Taxonomy
The following classes are recognized:
Arfiviricetes
Repensiviricetes
References
External links
Viruses
Single-stranded DNA viruses | Cressdnaviricota | [
"Biology"
] | 143 | [
"Virus stubs",
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,771,069 | https://en.wikipedia.org/wiki/Arfiviricetes | Arfiviricetes is a class of viruses.
Orders
The following orders are recognized:
Baphyvirales
Cirlivirales
Cremevirales
Mulpavirales
Recrevirales
Rivendellvirales
Rohanvirales
References
External links
Single-stranded DNA viruses | Arfiviricetes | [
"Biology"
] | 58 | [
"Virus stubs",
"Viruses"
] |
63,771,088 | https://en.wikipedia.org/wiki/Mulpavirales | Mulpavirales is an order of viruses.
Taxonomy
The following families are assigned to the order:
Metaxyviridae
Nanoviridae
References
Virus orders
Single-stranded DNA viruses | Mulpavirales | [
"Biology"
] | 38 | [
"Virus stubs",
"Viruses"
] |
63,771,107 | https://en.wikipedia.org/wiki/Geplafuvirales | Geplafuvirales is an order of viruses.
Families
The following families are recognized:
Geminiviridae
Genomoviridae
References
Single-stranded DNA viruses | Geplafuvirales | [
"Biology"
] | 34 | [
"Virus stubs",
"Viruses"
] |
63,771,142 | https://en.wikipedia.org/wiki/Pleolipoviridae | Pleolipoviridae is a family of DNA viruses that infect archaea.
Taxonomy
The following genera are recognized:
Alphapleolipovirus
Betapleolipovirus
Gammapleolipovirus
References
Monodnaviria
DNA viruses | Pleolipoviridae | [
"Biology"
] | 49 | [
"Virus stubs",
"Viruses",
"DNA viruses"
] |
63,771,242 | https://en.wikipedia.org/wiki/Bamfordvirae | Bamfordvirae is a kingdom of viruses. This kingdom is recognized for its use of double jelly roll major capsid proteins. It was formerly known as the PRD1-adenovirus lineage. The kingdom is named after Dennis H. Bamford who first promoted the evolutionary unity of all viruses encoding double jelly-roll major capsid proteins.
Taxonomy
Source:
The following phyla are recognized:
Nucleocytoviricota
Preplasmiviricota
There also exists an unassigned family:
Yaraviridae
References | Bamfordvirae | [
"Biology"
] | 110 | [
"Virus stubs",
"Viruses"
] |
63,771,247 | https://en.wikipedia.org/wiki/PET%20for%20bone%20imaging | Positron emission tomography for bone imaging, as an in vivo tracer technique, allows the measurement of the regional concentration of radioactivity proportional to the image pixel values averaged over a region of interest (ROI) in bones. Positron emission tomography is a functional imaging technique that uses [18F]NaF radiotracer to visualise and quantify regional bone metabolism and blood flow. [18F]NaF has been used for imaging bones for the last 60 years. This article focuses on the pharmacokinetics of [18F]NaF in bones, and various semi-quantitative and quantitative methods for quantifying regional bone metabolism using [18F]NaF PET images.
Use of [18F]NaF PET
The measurement of regional bone metabolism is critical to understand the pathophysiology of metabolic bone diseases.
Bone biopsy is considered the gold standard to quantify bone turnover; however, it is invasive, complex and costly to perform and subject to significant measurement errors.
Measurements of serum or urine biomarkers of bone turnover are simple, cheap, quick, and non-invasive in measuring changes in bone metabolism, but only provide information on the global skeleton.
The functional imaging technique of dynamic [18F]NaF PET scans can quantify regional bone turnover at specific sites of clinical importance such as the lumbar spine and hip and has been validated by comparison with the gold standard of bone biopsy.
Pharmacokinetics of [18F]NaF
The chemically stable anion of Fluorine-18-Fluoride is a bone-seeking radiotracer in skeletal imaging. [18F]NaF has an affinity to deposit at areas where the bone is newly mineralizing. Many studies have [18F]NaF PET to measure bone metabolism at the hip, lumbar spine, and humerus. [18F]NaF is taken-up in an exponential manner representing the equilibration of tracer with the extracellular and cellular fluid spaces with a half-life of 0.4 hours, and with kidneys with a half-life of 2.4 hours. The single passage extraction of [18F]NaF in bone is 100%. After an hour, only 10% of the injected activity remains in the blood.
18F- ions are considered to occupy extracellular fluid spaces because, firstly, they equilibrate with transcellular fluid spaces and secondly, they are not entirely extracellular ions. Fluoride undergoes equilibrium with hydrogen fluoride, which has a high permeability allowing fluoride to cross the plasma blood membrane. The fluoride circulation in red blood cells accounts for 30%. However, it is freely available to the bone surface for uptake because the equilibrium between erythrocytes and plasma is much faster than the capillary transit time. This is supported by studies reporting 100% single-passage extraction of whole-blood 18F- ion by bone and the rapid release of 18F- ions from erythrocytes with a rate constant of 0.3 per second.
[18F]NaF is also taken-up by immature erythrocytes in the bone marrow, which plays a role in fluoride kinetics. The plasma protein binding of [18F]NaF is negligible. [18F]NaF renal clearance is affected by diet and pH level, due to its re-absorption in the nephron, which is mediated by hydrogen fluoride. However, large differences in urine flow rate are avoided for controlled experiments by keeping patents well hydrated.
The exchangeable pool and the size of the metabolically active surfaces in bones determines the amount of tracer accumulated or exchanged with bone extracellular fluid, chemisorption onto hydroxyapatite crystals to form fluorapatite, as shown in Equation-1:
Equation-1
Fluoride ions from the crystalline matrix of bone are released when the bone is remodelled, thus providing a measure of the rate of bone metabolism.
Measuring SUV
Definition
The standardized uptake value (SUV) is defined as tissue concentration (KBq/ml) divided by activity injected normalized for body weight.
Appropriateness
The SUV measured from the large ROI smooths out the noise and, therefore, more appropriate in [18F]NaF bone studies as the radiotracer is fairly uniformly taken up throughout the bone. The measurement of SUV is easy, cheap, and quicker to perform, making it more attractive for clinical use. It has been used in diagnosing and assessing the efficacy of therapy. SUV can be measured at a single site, or the whole skeleton using a series of static scans and restricted by the small field-of-view of the PET scanner.
Known Issues
The SUV has emerged as a clinically useful, albeit controversial, semi-quantitative tool in PET analysis. Standardizing imaging protocols and measuring the SUV at the same time post-injection of the radiotracer, is necessary to obtain a correct SUV because imaging before the uptake plateau introduces unpredictable errors of up to 50% with SUVs. Noise, image resolution, and reconstruction do affect the accuracy of SUVs, but correction with phantom can minimize these differences when comparing SUVs for multi-centre clinical trials. SUV may lack sensitivity in measuring response to treatment as it is a simple measure of tracer uptake in bone, which is affected by the tracer uptake in other competing tissues and organs in addition to the target ROI.
Measuring Ki
The quantification of dynamic PET studies to measure Ki requires the measurement of the skeletal time-activity curves (TAC) from the region of interest (ROI) and the arterial input function (AIF), which can be measured in various different ways. However, the most common is to correct the image-based blood time-activity curves using several venous blood samples taken at discrete time points while the patient is scanned. The calculation of rate constants or Ki requires three steps:
Measurement of the arterial input function (AIF), which acts as the first input to the mathematical model of tracer distribution.
Measurement of the time-activity curve (TAC) within the skeletal region of interest, which acts as the second input to the mathematical model of tracer distribution.
Kinetic modelling of AIF and TAC using mathematical modelling to obtain net plasma clearance (Ki) to the bone mineral.
Spectral method
The method was first described by Cunningham & Jones in 1993 for the analysis of dynamic PET data obtained in the brain. It assumes that the tissue impulse response function (IRF) can be described as a combination of many exponentials. Since A tissue TAC can be expressed as a convolution of measured arterial input function with IRF, Cbone(t) can be expressed as:
where, is a convolution operator, Cbone(t) is the bone tissue activity concentration of tracer (in units: MBq/ml) over a period of time t, Cplasma(t) is the plasma concentration of tracer (in units: MBq/ml) over a period of time t, IRF(t) is equal to the sum of exponentials, β values are fixed between 0.0001 sec−1 and 0.1 sec−1 in intervals of 0.0001, n is the number of α components that resulted from the analysis and β1, β2,..., βn corresponds to the respective α1, α2,..., αn components from the resulted spectrum. The values of α are then estimated from the analysis by fitting multi-exponential to the IRF. The intercept of the linear fit to the slow component of this exponential curve is considered the plasma clearance (Ki) to the bone mineral.
Deconvolution method
The method was first described by Williams et al. in the clinical context. The method was used by numerous other studies. This is perhaps the simplest of all the mathematical methods for the calculation of Ki but the one most sensitive to noise present in the data. A tissue TAC is modelled as a convolution of measured arterial input function with IRF, the estimates for IRF are obtained iteratively to minimise the differences between the left- and right-hand side of the following Equation:
where, is a convolution operator, Cbone(t) is the bone tissue activity concentration of tracer (in units: MBq/ml) over a period of time t, Cplasma(t) is the plasma concentration of tracer (in units: MBq/ml) over a period of time t, and IRF(t) is the impulse response of the system (i.e., a tissue in this case). The Ki is obtained from the IRF in a similar fashion to that obtained for the spectral analysis, as shown in the figure.
Hawkins model
The measurement of Ki from dynamic PET scans require tracer kinetic modelling to obtain the model parameters describing the biological processes in bone, as described by Hawkins et al. Since this model has two tissue compartments, it is sometimes called a two-tissue compartmental model. Various different versions of this model exist; however, the most fundamental approach is considered here with two tissue compartments and four tracer-exchange parameters. The whole kinetic modelling process using Hawkins model can be summed up in a single image as seen on the right-hand-side. The following differential equations are solved to obtain the rate constants:
The rate constant K1 (in units: ml/min/ml) describes the unidirectional clearance of fluoride from plasma to the whole of the bone tissue, k2 (in units: min−1) describes the reverse transport of fluoride from the ECF compartment to plasma, k3 and k4 (in units min−1) describe the forward and backward transportation of fluoride from the bone mineral compartment.
Ki represents the net plasma clearance to bone mineral only. Ki is a function of both K1, reflecting bone blood flow, and the fraction of the tracer that undergoes specific binding to the bone mineral k3 / (k2 + k3). Therefore,
Hawkins et al. found that the inclusion of an additional parameter called fractional blood volume (BV), representing the vascular tissue spaces within the ROI, improved the data fitting problem, although this improvement was not statistically significant.
Patlak method
Patlak method is based on the assumption that the backflow of tracer from bone mineral to bone ECF is zero (i.e., k4=0). The calculation of Ki using Patlak method is simpler than using non-linear regression (NLR) fitting the arterial input function and the tissue time-activity curve data to the Hawkins model. The Patlak method can only measure bone plasma clearance (Ki), and cannot measure the individual kinetic parameters, K1, k2, k3, or k4.
The concentration of tracer in tissue region-of-interest can be represented as a sum of concentration in bone ECF and the bone mineral. It can be mathematically represented as
where, within the tissue region-of-interest from the PET image, Cbone(T) is the bone tissue activity concentration of tracer (in units: MBq/ml) at any time T, Cplasma(T) is the plasma concentration of tracer (in units: MBq/ml) at time T, Vo is the fraction of the ROI occupied by the ECF compartment, and is the area under the plasma curve is the net tracer delivery to the tissue region of interest (in units: MBq.Sec/ml) over time T. The Patlak equation is a linear equation of the form
Therefore, linear regression is fitted to the data plotted on Y- and X-axis between 4–60 minutes to obtain m and c values, where m is the slope of the regression line representing Ki and c is the Y-intercept of the regression line representing Vo.
Siddique–Blake method
The calculation of Ki using arterial input function, time-activity curve, and Hawkins model was limited to a small skeletal region covered by the narrow field-of-view of the PET scanner while acquiring a dynamic scan. However, Siddique et al. showed in 2012 that it is possible to measure Ki values in bones using static [18F]NaF PET scans. Blake et al. later showed in 2019 that the Ki obtained using the Siddique–Blake method has precision errors of less than 10%. The Siddique–Blake approach is based on the combination of the Patlak method, the semi-population based arterial input function, and the information that Vo does not significantly change post-treatment. This method uses the information that a linear regression line can be plotted using the data from a minimum of two time-points, to obtain m and c as explained in the Patlak method. However, if Vo is known or fixed, only one single static PET image is required to obtain the second time-point to measure m, representing the Ki value. This method should be applied with great caution to other clinical areas where these assumptions may not hold true.
SUV vs Ki
The most fundamental difference between SUV and Ki values is that SUV is a simple measure of uptake, which is normalized to body weight and injected activity. The SUV does not take into consideration the tracer delivery to the local region of interest from where the measurements are obtained, therefore, affected by the physiological process consuming [18F]NaF elsewhere in the body. On the other hand, Ki measures the plasma clearance to bone mineral, taking into account the tracer uptake elsewhere in the body affecting the delivery of tracer to the region of interest from where the measurements are obtained. The difference in the measurement of Ki and SUV in bone tissue using [18F]NaF are explained in more detail by Blake et al.
It is critical to note that most of the methods for calculating Ki require dynamic PET scanning over an hour, except, the Siddique–Blake methods. Dynamic scanning is complicated and costly. However, the calculation of SUV requires a single static PET scan performed approximately 45–60 minutes post-tracer injection at any region imaged within the skeleton.
Many researchers have shown a high correlation between SUV and Ki values at various skeletal sites. However, SUV and Ki methods can contradict for measuring response to treatment. Since SUV has not been validated against the histomorphometry, its usefulness in bone studies measuring response to treatment and disease progression is uncertain.
See also
Bone
Positron emission tomography
Time-activity curve
Arterial input function
Medical Imaging
Radiology
Molecular Imaging
Medical Imaging
Bone scintigraphy
References
American inventions
Antimatter
Neuroimaging
Radiation therapy
3D nuclear medical imaging
Medical physics
Medicinal radiochemistry
Armenian inventions | PET for bone imaging | [
"Physics",
"Chemistry"
] | 3,042 | [
"Antimatter",
"Applied and interdisciplinary physics",
"Medicinal radiochemistry",
"Positron emission tomography",
"Medical physics",
"Medicinal chemistry",
"Matter"
] |
63,771,285 | https://en.wikipedia.org/wiki/Megaviricetes | Megaviricetes is a class of viruses. The class contains giant viruses, all of which are nucleocytoplasmic large DNA viruses that are assigned to the phylum Nucleocytoviricota. Members of the Megaviricetes typically have genomes that are much larger than viruses assigned to other taxa, and also encode genes involved in DNA repair, DNA replication, transcription, translation, and other processes that viruses in other taxa usually lack. As well, the virus particles (virions) of some members of Megaviricetes are much larger in size than for other viruses, and can be larger than some bacteria.
Orders
The following orders are recognized:
Algavirales
Imitervirales
Pimascovirales
References
Virus classes | Megaviricetes | [
"Biology"
] | 159 | [
"Virus stubs",
"Viruses"
] |
63,771,377 | https://en.wikipedia.org/wiki/Pimascovirales | Pimascovirales is an order of viruses. The term is a portmanteau of a portmanteau of pitho-, irido-, marseille-, and ascoviruses.
Families
The following families are recognized:
Ascoviridae
Iridoviridae
Marseilleviridae
References
Viruses | Pimascovirales | [
"Biology"
] | 65 | [
"Virus stubs",
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,771,405 | https://en.wikipedia.org/wiki/Pokkesviricetes | Pokkesviricetes is a class of viruses.
Orders
The following orders are recognized:
Asfuvirales
Chitovirales
References
Viruses | Pokkesviricetes | [
"Biology"
] | 31 | [
"Virus stubs",
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,771,427 | https://en.wikipedia.org/wiki/Preplasmiviricota | Preplasmiviricota is a phylum of viruses. Its name means "precursor of certain plasmids".
Taxonomy
The phylum contains the following classes:
Ainoaviricetes
Maveriviricetes
Polintoviricetes
Tectiliviricetes
References
Viruses | Preplasmiviricota | [
"Biology"
] | 64 | [
"Virus stubs",
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,771,669 | https://en.wikipedia.org/wiki/Revtraviricetes | Revtraviricetes is a class of viruses that contains all viruses that encode a reverse transcriptase. The group includes all ssRNA-RT viruses (including the retroviruses) and dsDNA-RT viruses. It is the sole class in the phylum Artverviricota, which is the sole phylum in the kingdom Pararnavirae. The name of the group is a portmanteau of "reverse transcriptase" and -viricetes which is the suffix for a virus class.
Orders
The following orders are recognized:
Blubervirales (e.g. hepatitis B virus)
Ortervirales (retroviruses, Caulimoviridae and various LTR retrotransposons)
References
Viruses
Virus classes | Revtraviricetes | [
"Biology"
] | 157 | [
"Virus stubs",
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,771,705 | https://en.wikipedia.org/wiki/Sound%20scenography | Sound scenography (also known as acoustic scenography) is the process of staging spaces and environments through sound. It combines expertise from the fields of architecture, acoustics, communication, sound design and interaction design to convey artistic, historical, scientific, or commercial content or to establish atmospheres and moods.
Definition
Initially developed as a sub-discipline of scenography, it is now primarily used in the context of exhibitions, museums, media installations and trade fairs, as well as shops, adventure parks, spas, reception areas, and open-plan offices.
Distinct from other applications in sound design, spatial localisation plays a central role in sound scenography. Sound in contexts such as film soundtracks has a synchronised and standardised listening experience. The sound experience should be the same for every visitor at every position (and in every cinema). Because exhibition spaces are freely traversable and show audio-visual content at various stations across the room, sound scenography aims at providing every visitor with an individual listening experience with distinct start and end points as well as a distinct progression. Thus, the dramaturgy of the sound experience is no longer determined by the timeline of the soundtrack, but by the position and movement of the visitor.
Methods of Sound Scenography
Spaces can be staged with sound in various ways. Rooms have different tonal properties and acoustics depending on their architecture and interior design. Live musicians can spread across the room or play in motion, which is especially common in spatial music. The reproduction of sounds via loudspeakers, offers a wide range of possibilities for integrating sound into spaces and is therefore the most commonly used method. In that context, sound scenography is influenced from various practices in the wider field of sound design and composition, such as generative music, sonic interaction design, and sound masking. Loudspeaker systems used to distribute sound range from standard spatial audio setups to the more customised distributions common in sound installation, such as the Acousmatic Room Orchestration System. The spatial integration of sound delivered via headphones is a defining feature of interactive soundwalks. Leveraging technologies such as geolocation and head tracking, sounds are used to augment real environments in what the BBC's R&D department calls "Audio AR". In the more controlled environment of an exhibition, this approach has been used to create fully virtual sound environments.
Functions of Sound Scenography
Sound scenography performs many of the established functions of sound in film soundtracks. It gives emotional connotations to spaces, exhibits or even individual interactions through the use of sound. Soundscapes are used to establish atmospheres and moods with varying degrees of realism. Sound content is also used to evoke memories and associations. Soundscapes and musical accents clarify visual content or re-contextualise it. Content can also be conveyed purely sonically without accompanying visual media. Especially in connection with large-scale video projection, sound is used to direct the viewer's attention. In all these application areas, sound scenography relates the different sonic components of an exhibition to one another in order to create a coherent overall soundscape.
See also
Spatial music
Exhibit design
Sound Art
Acoustical engineering
References
Further reading
Franinović, K. & Serafin, Stefania (2013) Sonic Interaction Design, Cambridge: Massachusetts Institute of Technology
Atelier Brückner (2010) Scenography / Szenografie – Making spaces talk / Narrative Räume, Stuttgart: avedition
Minard, Robin (1993) Sound Environments – music for public spaces, Berlin: Akademie der Künste
Kiefer, Peter (2010) Klangräume der Kunst, Heidelberg: Kehrer Verlag
Cancellaro, Joseph (2006) Sound Design for Interactive Media, New York: Thomson Delmar Learning
Metzger, Christoph (2015) Architektur und Resonanz, Berlin: jovis Verlag GmbH
Plot #10 The Power of Sound, 2013
Design
Sound production
Film sound production | Sound scenography | [
"Engineering"
] | 811 | [
"Design"
] |
63,771,723 | https://en.wikipedia.org/wiki/Orthornavirae | Orthornavirae is a kingdom of viruses that have genomes made of ribonucleic acid (RNA), including genes which encode an RNA-dependent RNA polymerase (RdRp). The RdRp is used to transcribe the viral RNA genome into messenger RNA (mRNA) and to replicate the genome. Viruses in this kingdom share a number of characteristics which promote rapid evolution, including high rates of genetic mutation, recombination, and reassortment.
Viruses in Orthornavirae belong to the realm Riboviria. They are descended from a common ancestor that may have been a non-viral molecule that encoded a reverse transcriptase instead of an RdRp for replication. The kingdom is subdivided into five phyla that separate member viruses based on their genome type, host range, and genetic similarity. Viruses with three genome types are included: positive-strand RNA viruses, negative-strand RNA viruses, and double-stranded RNA viruses.
Many of the most widely known viral diseases are caused by members of this kingdom, including coronaviruses, the Ebola virus, influenza viruses, the measles virus, and the rabies virus, as well as the first virus ever discovered, tobacco mosaic virus. In modern history, RdRp-encoding RNA viruses have caused numerous disease outbreaks, and they infect many economically important crops. Most eukaryotic viruses, including most human, animal, and plant viruses, are RdRp-encoding RNA viruses. In contrast, there are relatively few prokaryotic viruses in the kingdom.
Etymology
The first part of Orthornavirae comes from Greek ὀρθός [orthós], meaning straight, the middle part, rna, refers to RNA, and -virae is the suffix used for virus kingdoms.
Characteristics
Structure
RNA viruses in Orthornavirae typically do not encode many proteins, but most positive-sense, single-stranded (+ssRNA) viruses and some double-stranded RNA (dsRNA) viruses encode a major capsid protein that has a single jelly roll fold, so named because the folded structure of the protein contains a structure that resembles a jelly roll. Many also possess an envelope, a type of lipid membrane that typically surrounds the capsid. In particular, the viral envelope is near-universal among negative-sense, single-stranded (-ssRNA) viruses.
Genome
Viruses in Orthornavirae have three different types of genomes: dsRNA, +ssRNA, and -ssRNA. Single-stranded RNA viruses have either a positive or negative sense strand, and dsRNA viruses have both. This structure of the genome is important in terms of transcription to synthesize viral mRNA as well as replication of the genome, both of which are carried out by the viral enzyme RNA-dependent RNA polymerase (RdRp), also called RNA replicase.
Replication and transcription
Positive-strand RNA viruses
Positive-strand RNA viruses have genomes that can function as mRNA, so transcription is not necessary. However, +ssRNA will produce dsRNA forms as part of the process of replicating their genomes. From the dsRNA, additional positive strands are synthesized, which may be used as mRNA or for genomes for progeny. Because +ssRNA viruses create intermediate dsRNA forms, they have to avoid the host's immune system in order to replicate. +ssRNA viruses accomplish this by replicating in membrane-associated vesicles that are used as replication factories. For many +ssRNA viruses, subgenomic portions of the genome will be transcribed to translate specific proteins, whereas others will transcribe a polyprotein that is cleaved to produce separate proteins.
Negative-strand RNA viruses
Negative-strand RNA viruses have genomes that function as templates from which mRNA can be synthesized directly by RdRp. Replication is the same process but executed on the positive sense antigenome, during which RdRp ignores all transcription signals so that a complete -ssRNA genome can be synthesized. -ssRNA viruses vary between those that initiate transcription by the RdRp creating a cap on the 5'-end (usually pronounced "five prime end") of the genome or by snatching a cap from host mRNA and attaching it to the viral RNA. For many -ssRNA viruses, at the end of transcription, RdRp stutters on a uracil in the genome, synthesizing hundreds of adenines in a row as part of creating a polyadenylated tail for the mRNA. Some -ssRNA viruses are essentially ambisense, and have proteins encoded by both the positive and negative strand, so mRNA is synthesized directly from the genome and from a complementary strand.
Double-stranded RNA viruses
For dsRNA viruses, RdRp transcribes mRNA by using the negative strand as a template. Positive strands may also be used as templates to synthesize negative strands for the construction of genomic dsRNA. dsRNA is not a molecule produced by cells, so cellular life has evolved mechanisms to detect and inactivate viral dsRNA. To counter this, dsRNA viruses typically retain their genomes inside of viral capsid in order to evade the host's immune system.
Evolution
RNA viruses in Orthornavirae experience a high rate of genetic mutations because RdRp is prone to making errors in replication since it typically lacks proofreading mechanisms to repair errors. Mutations in RNA viruses are often influenced by host factors such as dsRNA-dependent adenosine deaminases, which edit viral genomes by changing adenosines to inosines. Mutations in genes that are essential for replication lead to a reduced number of progeny, so viral genomes typically contain sequences that are highly conserved over time with relatively few mutations.
Many RdRp-encoding RNA viruses also experience a high rate of genetic recombination, though rates of recombination vary significantly, with lower rates in -ssRNA viruses and higher rates in dsRNA and +ssRNA viruses. There are two types of recombination: copy choice recombination and reassortment. Copy choice recombination occurs when the RdRp switches templates during synthesis without releasing the prior, newly created RNA strand, which generates a genome of mixed ancestry. Reassortment, which is restricted to viruses with segmented genomes, has segments from different genomes packaged into a single virion, or virus particle, which also produces hybrid progeny.
For reassortment, some segmented viruses package their genomes into multiple virions, which produces genomes that are random mixtures of parents, whereas for those that are packaged into a single virion, typically individual segments are swapped. Both forms of recombination can only occur if more than one virus is present in a cell, and the more alleles are present, the more likely recombination is to occur. A key difference between copy choice recombination and reassortment is that copy choice recombination can occur anywhere in a genome, whereas reassortment swaps fully-replicated segments. Therefore, copy choice recombination can produce non-functional viral proteins whereas reassortment cannot.
The mutation rate of a virus is associated with the rate of genetic recombinations. Higher mutation rates increase both the number of advantageous and disadvantageous mutations, whereas higher rates of recombination allows for beneficial mutations to be separated from deleterious ones. Therefore, higher rates of mutations and recombinations, up to a certain point, improve viruses' ability to adapt. Notable examples of this include reassortments that enable cross-species transmission of influenza viruses, which have led to numerous pandemics, as well as the emergence of drug-resistance influenza strains via mutations that were reassorted.
Phylogenetics
The exact origin of Orthornavirae is not well established, but the viral RdRp shows a relation to the reverse transcriptase (RT) enzymes of group II introns that encode RTs and retrotransposons, the latter of which are self-replicating DNA sequences that integrate themselves into other parts of the same DNA molecule. A larger study (2022) where new lieneages (phyla) were described, has suggested that RNA viruses descend from the RNA world, suggesting that retroelements (retrotransposons and group II introns) originated from an ancestor related to the phylum Lenarviricota and that members of a newly discovered Taraviricota lineage (phylum) would be the ancestors of all RNA viruses. According to this study the genomes of both dsRNA, +ssRNA and -ssRNA evolved independently and were altered several times in evolution.
Classification
RNA viruses that encode RdRp are assigned to the kingdom Orthornavirae, which contains six official phyla, six unofficial phyla and several taxa that are unassigned to a phylum due to lack of information. The five phyla are separated based on the genome types, host ranges, and genetic similarity of member viruses.
Phylum: Duplornaviricota, which contains dsRNA viruses that infect prokaryotes and eukaryotes, which do not cluster with members of Pisuviricota, and which encode a capsid composed of a 60 homo- or heterodimers of capsid proteins organized on a lattice with pseudo T = 2 symmetry
Phylum: Kitrinoviricota, which contains +ssRNA viruses that infect eukaryotes and which do not cluster with members of Pisuviricota
Phylum: Lenarviricota, which contains +ssRNA viruses that infect prokaryotes and eukaryotes and which do not cluster with members of Kitrinoviricota
Phylum: Negarnaviricota, which contains -ssRNA viruses that infect eukaryotes.
Phylum: Pisuviricota, which contains +ssRNA and dsRNA viruses that infect eukaryotes and which do not cluster with other phyla.
Phylum: Ambiviricota, which contains -ssRNA viruses of ambisense that infect fungi and enconding self-cleaving RNA ribozymes found in viroids.
(proposed) Phylum: Taraviricota, which contains basal dsRNA or +ssRNA viruses that most likely infect prokaryotes with deficient cell walls and eukaryotic mitochondria similar to mitoviruses (specif and is the first phylum discovered by the Tara Oceans expedition ("tara").
(proposed) Phylum: Artimaviricota, which contains dsRNA viruses that infect thermoacidophilic bacteria.
(proposed) Phylum: Arctiviricota, which contains an -ssRNA viruses abundant in the arctic ("arcti") that probably infects algae
(proposed) Phylum: Paraxenoviricota, which contains +ssRNA viruses which contain strange ("paraxeno") RdRp domain sequences and morphology
(proposed) Phylum: Pomiviricota, which contains two +ssRNA viruses which infect ambiguous hosts
(proposed) Phylum: Wamoviricota
The unassigned taxa are listed hereafter (-viridae denotes family and -virus denotes genus).
Birnaviridae
Permutotetraviridae
The kingdom contains three groups in the Baltimore classification system, which groups viruses together based on their manner of mRNA synthesis, and which is often used alongside standard virus taxonomy, which is based on evolutionary history. Those three groups are Group III: dsRNA viruses, Group IV: +ssRNA viruses, and Group V: -ssRNA viruses.
Disease
RNA viruses are associated with a wide range of disease, including many of the most widely known viral diseases. Notable disease-causing viruses in Orthornavirae include:
Coronaviruses
Crimean-Congo hemorrhagic fever orthonairovirus
Dengue virus
Ebolavirus
Hantaviruses
Hepatitis A virus
Hepatitis C virus
Hepatitis E virus
Human orthopneumovirus
Influenza viruses
Japanese encephalitis virus
Lassa mammarenavirus
Measles morbillivirus
Mumps orthorubulavirus
Norovirus
Poliovirus
Rabies lyssavirus
Rhinoviruses
Rift Valley fever phlebovirus
Rotavirus
Rubella virus
West Nile virus
Yellow fever virus
Zika virus
Animal viruses in Orthornavirae include orbiviruses, which cause various diseases in ruminants and horses, including Bluetongue virus, African horse sickness virus, Equine encephalosis virus, and epizootic hemorrhagic disease virus. The vesicular stomatitis virus causes disease in cattle, horses, and pigs. Bats harbor many viruses including ebolaviruses and henipaviruses, which also can cause disease in humans. Similarly, arthropod viruses in the Flavivirus and Phlebovirus genera are numerous and often transmitted to humans. Coronaviruses and influenza viruses cause disease in various vertebrates, including bats, birds, and pigs.
Plant viruses in the kingdom are numerous and infect many economically important crops. Tomato spotted wilt virus is estimated to cause more than US$1 billion in damages annually, affecting more than 800 plant species including chrysanthemum, lettuce, peanut, pepper, and tomato. Cucumber mosaic virus infects more than 1,200 plant species and likewise causes significant crop losses. Potato virus Y causes significant reductions in yield and quality for pepper, potato, tobacco, and tomato, and Plum pox virus is the most important virus among stone fruit crops. Brome mosaic virus, while not causing significant economic losses, is found throughout much of the world and primarily infects grasses, including cereals.
History
Diseases caused by RNA viruses in Orthornavirae have been known throughout much of history, but their cause was only discovered in modern times. As a whole, RNA viruses were discovered during a time period of major advancements in molecular biology, including the discovery of mRNA as the immediate carrier of genetic information for protein synthesis. Tobacco mosaic virus was discovered in 1898 and was the first virus to be discovered. Viruses in the kingdom that are transmitted by arthropods have been a key target in the development of vector control, which often aims to prevent viral infections. In modern history, numerous disease outbreaks have been caused by RdRp-encoding RNA viruses, including outbreaks caused by coronaviruses, ebola, and influenza.
Orthornavirae was established in 2019 as a kingdom within the realm Riboviria, intended to accommodate all RdRp-encoding RNA viruses. Prior to 2019, Riboviria was established in 2018 and included only RdRp-encoding RNA viruses. In 2019, Riboviria was expanded to also include reverse transcribing viruses, placed under the kingdom Pararnavirae, so Orthornavirae was established to separate RdRp-encoding RNA viruses from reversing transcribing viruses.
Gallery
Notes
References
RNA
RNA viruses
Viruses
Kingdoms (biology)
Riboviria | Orthornavirae | [
"Biology"
] | 3,142 | [
"Viruses",
"Riboviria"
] |
63,771,745 | https://en.wikipedia.org/wiki/Duplornaviricota | Duplornaviricota is a phylum of RNA viruses, which contains all double-stranded RNA viruses, except for those in phylum Pisuviricota. Characteristic of the group is a viral capsid composed of 60 homo- or heterodimers of capsid protein on a pseudo-T=2 lattice. Duplornaviruses infect both prokaryotes and eukaryotes. The name of the group derives from Italian duplo which means double (a reference to double-stranded), rna for the type of virus, and -viricota which is the suffix for a virus phylum.
Classes
The following classes are recognized:
Chrymotiviricetes
Resentoviricetes
Vidaverviricetes
References
Viruses | Duplornaviricota | [
"Biology"
] | 163 | [
"Virus stubs",
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,771,768 | https://en.wikipedia.org/wiki/Ghabrivirales | Ghabrivirales is an order of double-stranded RNA viruses. It is the only order in the class Chrysmotiviricetes. The name of the class is a portmanteau of member families: chrysoviridae, megabirnaviridae, and totiviridae; and -viricetes which is the suffix for a virus class. The name of the order derives from Said Ghabrial, a pioneering researcher who studied viruses in this order, and -virales which is the suffix for a virus order.
Taxonomy
The following families are recognized:
Chrysoviridae
Megabirnaviridae
Quadriviridae
Totiviridae
References
Viruses | Ghabrivirales | [
"Biology"
] | 142 | [
"Virus stubs",
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,771,874 | https://en.wikipedia.org/wiki/Kitrinoviricota | Kitrinoviricota is a phylum of RNA viruses that includes all positive-strand RNA viruses that infect eukaryotes and are not members of the phylum Pisuviricota or Lenarviricota. The name of the group derives from Greek κίτρινος (kítrinos), which means yellow (a reference to yellow fever virus), and -viricota, which is the suffix for a virus phylum.
Classes
The following classes are recognized:
Alsuviricetes
Flasuviricetes
Magsaviricetes
Tolucaviricetes
References
Viruses | Kitrinoviricota | [
"Biology"
] | 132 | [
"Virus stubs",
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,771,890 | https://en.wikipedia.org/wiki/Alsuviricetes | Alsuviricetes is a class of positive-strand RNA viruses which infect eukaryotes. The name of the group is a syllabic abbreviation of "alpha supergroup" with the suffix -viricetes indicating a virus class.
Taxonomy
The following orders are recognized:
Hepelivirales
Martellivirales
Tymovirales
References
Tymovirales
Viruses | Alsuviricetes | [
"Biology"
] | 79 | [
"Virus stubs",
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,771,902 | https://en.wikipedia.org/wiki/Hepelivirales | Hepelivirales is an order of viruses.
Taxonomy
The following families are recognized:
Alphatetraviridae
Benyviridae
Hepeviridae
Matonaviridae
References
Viruses | Hepelivirales | [
"Biology"
] | 39 | [
"Virus stubs",
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,771,951 | https://en.wikipedia.org/wiki/Martellivirales | Martellivirales is an order of viruses.
Taxonomy
The following families are recognized:
Bromoviridae
Closteroviridae
Endornaviridae
Kitaviridae
Mayoviridae
Togaviridae
Virgaviridae
References
Viruses | Martellivirales | [
"Biology"
] | 50 | [
"Virus stubs",
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,771,982 | https://en.wikipedia.org/wiki/Nodamuvirales | Nodamuvirales is an order of positive-strand RNA viruses which infect eukaryotes. The name of the group is a contraction of "Nodamura virus" and -virales which is the suffix for a virus order.
Taxonomy
The following families are recognized:
Nodaviridae
Sinhaliviridae
References
Viruses | Nodamuvirales | [
"Biology"
] | 70 | [
"Virus stubs",
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,772,005 | https://en.wikipedia.org/wiki/Tolivirales | Tolivirales is an order of RNA viruses which infect insects and plants. Member viruses have a positive-sense single-stranded RNA genome. The virions are non-enveloped, spherical, and have an icosahedral capsid. The name of the group is a syllabic abbreviation of "tombusvirus-like" with the suffix -virales indicating a virus order.
Taxonomy
The following families are recognized:
Carmotetraviridae
Tombusviridae
References
Viruses | Tolivirales | [
"Biology"
] | 101 | [
"Virus stubs",
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,772,022 | https://en.wikipedia.org/wiki/Lenarviricota | Lenarviricota is a phylum of RNA viruses that includes all positive-strand RNA viruses that infect prokaryotes. Some members also infect eukaryotes. Most of these viruses do not have capsids, except for the genus Ourmiavirus. The name of the group is a syllabic abbreviation of the names of founding member families "Leviviridae and Narnaviridae" with the suffix -viricota, denoting a virus phylum.
Phylogenetics
Lenarviricota is the first branch of RNA viruses to emerge, since they are the most basal branch. Most of its members, the leviviruses (class Leviviricetes), only infect prokaryotes, and their known level of diversity has grown dramatically in recent years, which suggests that the RNA viruses may be more widespread in prokaryotes than previously believed.
It has been suggested that the origin of Lenarviricota may predate that of the last universal common ancestor (LUCA). Lenarviricota viruses appear to have arisen from a primordial RdRP of the RNA-protein world that gave rise to leviviruses (class Leviviricetes). It has also been suggested that the retroelements of cellular life (group II introns and retrotransposons) evolved from a shared ancestor with Lenarviricota.
The eukaryotic RNA viruses without capsids, Mitoviridae, Narnaviridae and Botourmiaviridae, arose from the leviviruses with the loss of the capsid during the time that eukaryogenesis occurred, when the bacterial endosymbiont became the mitochondria. The genus Ourmiavirus arose by recombination between a non-capsid botourmiavirus and a virus from the family Tombusviridae, which inherited its capsid proteins.
Taxonomy
The following classes are recognized:
Amabiliviricetes
Howeltoviricetes
Leviviricetes
Miaviricetes
References
Viruses | Lenarviricota | [
"Biology"
] | 420 | [
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,772,093 | https://en.wikipedia.org/wiki/Botourmiaviridae | Botourmiaviridae is a family of positive-strand RNA viruses which infect plants and fungi. The family includes four genera: Ourmiavirus, Botoulivirus, Magoulivirus and Scleroulivirus. Members of genus Ourmiavirus infect plants and the other genera infect fungi. The member viruses have genomes which range from 2900 to 4800 nucleotides.
Structure
Ourmiaviruses are the only members of the family that have a viral structure. The other members are naked and have no viral envelope or capsid. Ourmiaviruses are plant viruses that have a bacilliform virion composed of a single capsid protein. The virions have a series of discrete lengths from 30 to 62 nm.
Genome
Members of the family Botourmiaviridae have positive-sense, single-stranded RNA genomes. Contrary to the hosts they infect (plants and fungus), their genome is concise and has few redundancies. The genome of the genus Ourmiavirus has three segments that encode the capside protein (CP), movement protein (MP), and RNA-dependent RNA polymerase (RdRp). The length of the genome is around 4800 nucleotides. The genomes of the other three genera of the family are nonsegmented and have lengths which range from 2000 to 3200 nucleotides. The genomes of these fungal viruses only encode an RNA-dependent RNA polymerase and have no structural proteins.
Taxonomy
The family has six genera:
Botoulivirus
Magoulivirus
Ourmiavirus
Penoulivirus
Rhizoulivirus
Scleroulivirus
References
Viruses
Virus families | Botourmiaviridae | [
"Biology"
] | 348 | [
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,772,134 | https://en.wikipedia.org/wiki/Fish%20coloration | Fish coloration, a subset of animal coloration, is extremely diverse. Fish across all taxa vary greatly in their coloration through special mechanisms, mainly pigment cells called chromatophores. Fish can have any colors of the visual spectrum on their skin, evolutionarily derived for many reasons. There are three factors to coloration, brightness (intensity of light), hue (mixtures of wavelengths), and saturation (the purity of wavelengths). Fish coloration has three proposed functions: thermoregulation, intraspecific communication, and interspecific communication. Fishes' diverse coloration is possibly derivative of the fact that "fish most likely see colors very differently than humans".
Mechanisms
Fish coloration is produced through specialized cells called chromatophores. The dermal chromatophore is a basic color unit in amphibians, reptiles, and fish which has three cell layers: "the xanthophore (contains carotenoid and pteridine pigments), the iridophore (reflects color structurally), and the melanophore (contains melanin)". The pigments in the chromatophores are generally classified into two groups: melanin (makes browns, grays, and blacks), and carotenoids (makes reds, oranges, and yellows). Xanthophores, iridophores, and melanophores "originate from neural crest‐derived stem cells associated with the dorsal root ganglia of the peripheral nervous system".
Specific mechanisms by color
Black: produced by melanin granules dispersing inside the melanophore
Gray and brown: produced by melanin granules concentrating inside the melanophore
White: appears from light reflected by crystals of guanine in iridophores and leucophores
Red, orange, yellow: produced by carotenoids that come from fish's diet
Green, blue, violet: (generally) structural colors produced by the reflection and refraction of light by the skin and scale layers
An example of a family of fish that is widely known for their highly varied and bright coloration are the Labridae (wrasses) and Scaridae (parrotfish). These fishes are known to possess all of the above pigments in different ratios depending on where they live in relation to the coral reef environment. Different wavelengths, and thus different colors, travel differently and therefore appear differently depending on the depth of the water and the things on which they are reflecting.
Evolutionary function
Signalling
One way that fish coloration can be categorized is into "static" or "dynamic" coloration/displays. Static coloration often serves as an "identification badge" for information such as species, reproductive condition, sex, or age. An example of a type of static coloration that conveys clear information to predators of different species is aposematic coloration. An example of aposematic coloration is in the lionfish (Pterois sp.). Dynamic displays consist of either changes of color or "rapid exposure of colored, previously hidden structures" such as colored fins that can be erected at will, colored mouth opening and closing, or flaring gills with bright coloration on the gill margins. For example, grunts have a bright red lining on their mouth that they can show by opening it in a head-to-head encounter. Another common example is the betta fish, or Siamese fighting fish, that will flare its gills as an aggressive behavior. These gills have brightly colored margins that contrast the rest of the body.
Camouflage
Some fish are famous for their camouflage, and it comes in many forms. Camouflage is when a fish is trying to blend in with its background, or not look obvious. Some major forms of camouflage in fish include protective resemblance, disruptive coloration, countershading, mirror-siding, and transparency.
Protective resemblance
Protective resemblance is blending in, or resembling an object that is not of interest to a predator and is thus inconspicuous. One example is the juvenile Platax orbicularis that resembles a leaf floating in the water. Another example is the Hippocampus bargibanti that resembles the coral it hooks to.
Disruptive coloration
Disruptive coloration in fish functions to break up the fishlike outline. This can be done with stripes, bars, or spot patterns on the fish. Bars are lines that go dorsal to ventral, for example in the blackbanded sunfish. Stripes are lines that go from the snout to the tail, such as in Aeoliscus strigatus. Stripes and bars often continue through the eye to break up the easily recognized vertebrate eye.
Countershading
Countershading (dark on top and light on the bottom) in fish works well in conjunction with how light comes into the water from above. Looking from below up at a countershaded fish, the light belly will blend in with the light surface of the water. Looking from above down at a countershaded fish, the dark back will blend with the dark water below. An example of countershading in fish is the Atlantic bluefin tuna. Some fish are even known to have reverse countershading, being light on the dorsal side and dark on the ventral side. An example of this is Tyrannochromis macrostoma, which turns upside-down right before it strikes, essentially disappearing.
Mimicry
Mimicry is defined as an animal resembling a different animal that is avoided or not commonly preyed upon and is thus conspicuous. There are two types of mimicry: Müllerian mimicry and Batesian mimicry. An example of Batesian mimicry in fishes are the Centrogeniidae (false scorpionfishes), that resemble the Scorpaenidae (scorpionfishes). Another example of Batesian mimicry is the ringed snake eel (Myrichthys colubrinus) that mimics the venomous sea snake Laticauda colubrina. An example of Müllerian mimicry is in saber-toothed blennies. The Meiacanthus atrodorsalis and the Plagiotremus laudandus, both venomous, resemble each other and the Meiacanthus oualanensis and the Plagiotremus laudandus flavus, also both venomous, resemble each other.
Color change
Color change in fishes can be roughly divided into two categories: physiological color change and morphological color change. Physiological color change is considered to be more rapid and consist of motile chromatophore responses, while morphological color change consists of the density and morphology of chromatophores changing. Overall, morphological color changes are considered to be a "physiological phenomena involved in the balance between differentiation [of melanophores] and apoptosis of chromatophores" but are still being studied; that is to say it has to do with the synthesis of pigment. The genetic factors behind natural morph variants of color in fish are still mostly undiscovered. Some hormonal factors of morphological color change in fish include α-MSH, prolactin, estrogen, noradrenaline, MCH, and possibly melatonin. Some of these are also involved in physiological color change. In physiological color change, there is also neurohumoral regulation of chromatophores in fish. Additionally, there have been found to be "differences at the intracellular level where fish chromatophores show smaller, better coordinated, and higher speed of the pigment organelles" in comparison to color-changing frogs.
An example of physiological color change is found in the black-spotted rockskipper (Entomacrodus striatus). They are known to change color rapidly using their chromatophores, which is thought to enhance their crypsis in the "high-contrast environment of the rock wall". Another example of physiological color change is in the body and the eyes of guppy juveniles and Nile tilapia.
An example of morphological color change is in the Midas cichlid (Amphilophus citrinellus), that has "normal" and "gold" polymorphisms. Most of these cichlids maintain a "normal" grayish color pattern from juvenile to adult. However some of these species undergo morphological color change over their lifetimes, growing to be a gold or white color pattern as an adult. Another example of a fish that undergo morphological color change is the Hyphessobrycon myrmex sp. nov.. Juveniles are pale yellow and females maintain that color as adults. Males undergo morphological color change and become red or orange
References
External links
https://reefci.com/2013/10/31/significance-of-colors-and-patterns-of-coral-reef-fishes-an-overview/
https://www.jstor.org/stable/2407979
https://doi.org/10.1111/ele.13180
Enhance Guppy Color
https://onlinelibrary.wiley.com/doi/full/10.1111/pcmr.12040
Evolution of vertebrates
Mimicry
Warning coloration
Camouflage
Articles containing video clips | Fish coloration | [
"Biology"
] | 1,887 | [
"Camouflage",
"Mimicry",
"Biological defense mechanisms"
] |
63,772,144 | https://en.wikipedia.org/wiki/Pisuviricota | Pisuviricota is a phylum of RNA viruses that includes all positive-strand and double-stranded RNA viruses that infect eukaryotes and are not members of the phylum Kitrinoviricota, Lenarviricota or Duplornaviricota. The name of the group is a syllabic abbreviation of “picornavirus supergroup” with the suffix -viricota, indicating a virus phylum. Phylogenetic analyses suggest that Birnaviridae and Permutotetraviridae, both currently unassigned to a phylum in Orthornavirae, also belong to this phylum and that both are sister groups. Another proposed family of the phylum is unassigned Polymycoviridae in Riboviria.
Classes
The following classes are recognized:
Duplopiviricetes
Pisoniviricetes
Stelpaviricetes
References
Viruses | Pisuviricota | [
"Biology"
] | 194 | [
"Virus stubs",
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,772,166 | https://en.wikipedia.org/wiki/Durnavirales | Durnavirales is an order of double-stranded RNA viruses which infect eukaryotes. The name of the group derives from Italian duplo which means double (a reference to double-stranded), rna for the type of virus, and -virales which is the suffix for a virus order.
Families
The following families are recognized:
Amalgaviridae
Curvulaviridae
Hypoviridae
Partitiviridae
Picobirnaviridae
References
Viruses | Durnavirales | [
"Biology"
] | 100 | [
"Virus stubs",
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,772,180 | https://en.wikipedia.org/wiki/Pisoniviricetes | Pisoniviricetes is a class of positive-strand RNA viruses which infect eukaryotes. A characteristic of the group is a conserved 3C-like protease from the PA clan of proteases for processing the translated polyprotein. The name of the group is a portmanteau of member orders "picornavirales, sobelivirales, nidovirales" and -viricetes which is the suffix for a virus class.
Orders
The following orders are recognized:
Nidovirales
Picornavirales
Sobelivirales
References
Viruses | Pisoniviricetes | [
"Biology"
] | 123 | [
"Virus stubs",
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,772,189 | https://en.wikipedia.org/wiki/Sobelivirales | Sobelivirales is an order of RNA viruses which infect eukaryotes. Member viruses have a positive-sense single-stranded RNA genome. The name of the group is a portmanteau of member orders "sobemovirus-like" and -virales which is the suffix for a virus order.
Taxonomy
The following families are recognized:
Alvernaviridae
Barnaviridae
Solemoviridae
References
Viruses | Sobelivirales | [
"Biology"
] | 90 | [
"Virus stubs",
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,772,201 | https://en.wikipedia.org/wiki/Stelpaviricetes | Stelpaviricetes is a class of non-enveloped, positive-strand RNA viruses which infect plants and animals. Characteristic of the group is a VPg protein attached to the 5'-end of the genome and a conserved 3C-like protease from the PA clan of proteases for processing the translated polyprotein. The name of the group is a syllabic abbreviation of member orders "stellavirales, patatavirales" with the suffix -viricetes denoting a virus class.
Orders
The following orders are recognized:
Patatavirales
Stellavirales
References
Viruses | Stelpaviricetes | [
"Biology"
] | 125 | [
"Virus stubs",
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,772,953 | https://en.wikipedia.org/wiki/Otolin | Otolin is a glycoprotein found in the vertebrate inner ear.
Modifications
Otolin is modified after it is translated, with hydroxylated prolines and two glycosylated lysines with glucosyl-galactosyl groups.
Substructure
The gene for otolin in mice is on chromosome 3E12. In humans it is located at 3q26.1
At the N-terminal end there is a signal peptide. The N-terminal end has four cysteine residues. Adjacent to this is a stiff collagen domain with 75 Gly-X-Y repeats. It also contains a cysteine residue, and in human otolin, there are four cystein residues in this domain. At the opposite end is the C1q domain. The otolin gene in mammals contains four introns and five exons.
Superstructure
Otolin combines with several other otolin molecules to form an oligomer, probably a trimer. It also binds to otoconin-90 and cerebellin-1.
Production
Otolin is produced by the vestibular support cells in the utricle, saccule, the three semicircular canal cristae, and the tectorial membrane. In teleosts (fish), otolin is found in the otolith and it is required to anchor the otolith in position.
References
Glycoproteins | Otolin | [
"Chemistry"
] | 296 | [
"Glycoproteins",
"Glycobiology"
] |
63,773,649 | https://en.wikipedia.org/wiki/The%20Tower%20of%20Hanoi%20%E2%80%93%20Myths%20and%20Maths | The Tower of Hanoi – Myths and Maths is a book in recreational mathematics, on the tower of Hanoi, baguenaudier, and related puzzles. It was written by Andreas M. Hinz, Sandi Klavžar, Uroš Milutinović, and Ciril Petr, and published in 2013 by Birkhäuser, with an expanded second edition in 2018. The Basic Library List Committee of the Mathematical Association of America has suggested its inclusion in undergraduate mathematics libraries.
Topics
Although this book is in recreational mathematics, it takes its subject seriously, and brings in material from automata theory, computational complexity, the design and analysis of algorithms, graph theory, and group theory, topology, fractal geometry, chemical graph theory, and even psychology (where related puzzles have applications in psychological testing).
The 1st edition of the book had 10 chapters, and the 2nd edition has 11. In both cases they begin with chapter zero, on the background and history of the Tower of Hanoi puzzle, covering its real-world invention by Édouard Lucas and in the mythical backstory he invented for it. Chapter one considers the Baguenaudier puzzle (or, as it is often called, the Chinese rings), related to the tower of Hanoi both in the structure of its state space and in the fact that it takes an exponential number of moves to solve, and likely the inspiration for Lucas. Chapter two introduces the main topic of the book, the tower of Hanoi, in its classical form in which one must move disks one-by-one between three towers, always keeping the disks on each tower sorted by size. It provides several different algorithms for solving the classical puzzle (in which the disks begin and end all on a single tower) in as few moves as possible, and for collecting all disks on a single tower when they begin in other configurations, again as quickly as possible. It introduces the Hanoi graphs describing the state space of the puzzle, and relates numbers of puzzle steps to distances within this graph. After a chapter on "irregular" puzzles in which the initial placement of disks on their towers is not sorted, chapter four discusses the "Sierpiński graphs" derived from the Sierpiński triangle; these are closely related to the three-tower Hanoi graphs but diverge from them for higher numbers of towers of Hanoi or higher-dimensional Sierpinski fractals.
The next four chapters concern additional variants of the tower of Hanoi, in which more than three towers are used, the disks are only allowed to move between some of the towers or in restricted directions between the towers, or the rules for which disks can be placed on which are modified or relaxed. A particularly important case is the Reve's puzzle, in which the rules are unchanged except that there are four towers instead of three. An old conjecture concerning the minimum possible number of moves between two states with all disks on a single tower was finally proven in 2014, after the publication of the first edition of the book, and the second edition includes this material.
Some of the definitions and proofs are extended into the book's many exercises. A new chapter in the second edition provides hints and partial solutions, and the final chapter collects open problems and (in the second edition) provides updates to previously-listed problems. Many color illustrations and photographs are included throughout the book.
Audience
The book can be read both by mathematicians working on topics related to the tower of Hanoi puzzle, and by a general audience interested in recreational mathematics. Reviewer László Kozma describes the book as essential reading for the first type of audience and (despite occasional heavy notation and encyclopedic detail) accessible and interesting to the second type, even for readers with only a high school level background in mathematics. On the other hand, reviewer Cory Palmer cautions that "this book is not for a casual reader", adding that a good understanding of combinatorics is necessary to read it, and reviewer Charles Ashbacher suggests that it has enough depth of content to be the topic of an advanced undergraduate elective course.
Although generally positive, reviewer S. V. Nagaraj complains about a "significant number of errors" in the book. Reviewer Andrew Percy calls it "an enjoyable adventure", "humorous, and very thorough". Reviewer Martin Klazar calls the book "wonderful", recommending it to anyone interested in recreational mathematics or mathematics more generally.
References
External links
Home page
Mechanical puzzles
Mathematics books
2013 non-fiction books
2018 non-fiction books
Birkhäuser books | The Tower of Hanoi – Myths and Maths | [
"Mathematics"
] | 916 | [
"Recreational mathematics",
"Mechanical puzzles"
] |
63,774,269 | https://en.wikipedia.org/wiki/NGC%20861 | NGC 861 is a spiral galaxy in the constellation Triangulum. It is estimated to be 360 million light-years from the Milky Way and has a diameter of approximately 165,000 light-years. The object was discovered on September 18, 1865 by Heinrich d'Arrest.
See also
List of NGC objects (1–1000)
References
0861
Spiral galaxies
Triangulum
008652 | NGC 861 | [
"Astronomy"
] | 81 | [
"Triangulum",
"Constellations"
] |
63,774,288 | https://en.wikipedia.org/wiki/Metallurgical%20furnace | A metallurgical furnace, often simply referred to as a furnace when the context is known, is an industrial furnace used to heat, melt, or otherwise process metals. Furnaces have been a central piece of equipment throughout the history of metallurgy; processing metals with heat is even its own engineering specialty known as pyrometallurgy.
One important furnace application, especially in iron and steel production, is smelting, where metal ores are reduced under high heat to separate the metal content from mineral gangue. The heat energy to fuel a furnace may be supplied directly by fuel combustion or by electricity. Different processes and the unique properties of specific metals and ores have led to many different furnace types.
Air blast furnaces
Many furnace designs for smelting combine ore, fuel, and other reagents like flux in a single chamber. Mechanisms, such as bellows or motorized fans, then drive pressurized blasts of air into the chamber. These blasts make the fuel burn hotter and drive chemical reactions.
Furnaces of this type include:
The blast furnace, used to produce pig iron from iron ore. These can be subdivided into:
Cold blast furnaces
Hot blast furnaces
The bloomery, a precursor to the blast furnace that produces sponge iron from ore
The blowing house, a traditional furnace for smelting tin
The smeltmill, a traditional furnace for smelting lead
Blowing in
Even smaller, pre-industrial bloomeries possess significant thermal mass. Raising a cold furnace to the necessary temperature for smelting iron requires a significant amount of energy, regardless of modern technology. For this reason, metallurgists will try their best to keep blast furnaces running continuously, and shutting down a furnace is seen as an unfortunate event.
Conversely, starting up a new furnace, or one that had been temporarily shut down, is often a special occasion. In traditional bloomeries, several rounds of fuel would need to be burnt away before the furnace was ready to accept a charge of ore. In English, this process became known as "blowing in" the furnace, while a furnace that had to be shut down and went cold had been "blown out", terms that are still applied to contemporary blast furnaces.
Reverberatory furnaces
A reverberatory furnace still exposes the reaction chamber, where metal or ore is combined with reagents, to a stream of exhaust gases. However, no fuel is directly added to the chamber, and combustion occurs in a separate chamber. Furnaces of this type include:
The open hearth furnace, a 19th-20th century steelmaking method for refining pig iron into steel
The puddling furnace, a 18th-19th century method for refining pig iron into wrought iron
Refining converters
In metallurgy, furnaces used to refine metals further, particularly iron into steel, are also often called converters:
Steelmaking converters
The basic oxygen furnace
The Bessemer converter
The Manhès–David converter for refining copper matte into pure "blister" copper
Electric furnaces
Just as other industries have trended towards electrification, electric furnaces have become prevalent in metallurgy. However, while any furnace can theoretically use an electrical heating element, process specifics mostly limit this approach to furnaces with lower power demands.
Instead, electric metallurgical furnaces often apply an electric current directly to batches of metal. This is particularly useful for recycling (still relatively pure) scrap metal, or remelting ingots for casting in foundries. The absence of any fuel or exhaust gases also makes these designs versatile for heating all kinds of metals. Such designs include:
Electric arc furnaces (EAFs), which apply current to the metal via electrodes over an electric arc
The Flodin furnace is an early EAF, specially designed to smelt iron from ore through the direct addition of carbon
Electric induction furnaces, which heat the metal through eddy currents, requiring metal mostly free of gangue and corrosion
Other furnaces
Other metallurgical furnaces have special design features or uses. One function is heating material short of melting, in order to perform heat treatment or hot working. Basic furnaces used this way include:
A forge is the traditional metalsmith's hearth for heating metal while forging
Soaking pits are large heated chambers, typically in-ground, where steel slabs are reheated before rolling
Another class of furnaces isolate the material from the surrounding atmosphere and contaminants, enabling advanced heat treatments and other techniques:
Muffle furnaces enclose the material to keep out contaminants and divert any exhaust away from the area
Autoclaves are reinforced, seal airtight, and can expose material to heat and elevated pressure
Vacuum furnaces are similar to autoclaves, but expose the material to a vacuum instead
Notes
References
Industrial furnaces | Metallurgical furnace | [
"Chemistry"
] | 978 | [
"Metallurgical processes",
"Industrial furnaces"
] |
63,774,442 | https://en.wikipedia.org/wiki/NGC%20862 | NGC 862 is an elliptical galaxy located in the constellation of Phoenix about 241 million light years from the Milky Way. It was discovered by the British astronomer John Herschel in 1834.
See also
List of NGC objects (1–1000)
References
Elliptical galaxies
0862
Phoenix (constellation)
008487 | NGC 862 | [
"Astronomy"
] | 63 | [
"Phoenix (constellation)",
"Constellations"
] |
63,775,150 | https://en.wikipedia.org/wiki/NGC%202014 | NGC 2014 is a red emission nebula surrounding an open cluster of stars in the Large Magellanic Cloud, at a distance of about 163,000 light-years.
The nebula was discovered on 3 August 1826 by Scottish astronomer James Dunlop. Together with NGC 2020 it makes up what is called the Cosmic Reef.
References
External links
Emission nebulae
Large Magellanic Cloud
Dorado
2014 | NGC 2014 | [
"Astronomy"
] | 77 | [
"Nebula stubs",
"Dorado",
"Astronomy stubs",
"Constellations"
] |
63,775,376 | https://en.wikipedia.org/wiki/Terbium%28IV%29%20oxide | Terbium(IV) oxide is an inorganic compound with a chemical formula TbO2. It can be produced by oxidizing terbium(III) oxide by oxygen gas at 1000 atm and 300 °C.
Decomposition
Terbium(IV) oxide starts to decompose at 340 °C, producing Tb5O8 and oxygen:
5 TbO2 → Tb5O8 + O2
References
See also
Terbium(III) oxide
Terbium(III,IV) oxide
Terbium compounds
Oxides | Terbium(IV) oxide | [
"Chemistry"
] | 108 | [
"Oxides",
"Salts"
] |
63,775,573 | https://en.wikipedia.org/wiki/PGC%2013809 | PGC 13809 is a spiral, almost edge-on galaxy in the constellation Fornax. It was discovered by the European Southern Observatory and it is a member of the Fornax Cluster.
PGC 13809 has a Hubble classification of Sc, indicating it is an unbarred spiral galaxy with loose spiral arms. It is also seen nearly edge-on, with an angle of about ≈80 degrees (≈80°). Its size on the night sky is 4.8' x 0.8', indicating a real size of about 90,000 light-years, so PGC 13809 is slightly smaller than the Milky Way. It is also one of the larger galaxies in the Fornax Cluster, a cluster of 200 galaxies. Its magnitude is 12.6.
With a redshift of 1838 km/s, it is one of the faster moving galaxies in the Fornax Cluster, but it is close to the central giant elliptical galaxy NGC 1399, so gravitational reaction is possible.
References
Fornax Cluster
Spiral galaxies
Fornax | PGC 13809 | [
"Astronomy"
] | 221 | [
"Fornax",
"Constellations"
] |
63,780,293 | https://en.wikipedia.org/wiki/Tire-derived%20aggregate | Tire-derived aggregate (TDA) is a building material made of recycled tires, which are shredded into pieces of varying sizes. It is commonly used in construction projects because it is sustainable and lightweight, along with being less expensive than many competing available materials. In 2007, an estimated 561.6 thousand tons (about 509 metric tons) of TDA were produced. This accounted for about 12 percent of the total recycled tire material used. Particle sizes less than 12mm are considered crumb rubber.
Applications:
stormwater management due to high permeability
road fill and parking lots improves weak soil and for frost heave reduction in cold climates
landfilling due to permeability for leachate collection, gas collection
sight, slope, landslide stabilization due to lower hydrostatic pressure than soil
vibration mitigation due to absorption capacity
backfill for driveways, septic tanks, sidewalks, basements, etc.
soft surfaces for walking paths, playgrounds, etc.
References
Tire industry
Building materials | Tire-derived aggregate | [
"Physics",
"Engineering"
] | 201 | [
"Building engineering",
"Construction",
"Materials",
"Building materials",
"Matter",
"Architecture"
] |
63,780,788 | https://en.wikipedia.org/wiki/Katalin%20Karik%C3%B3 | Katalin "Kati" Karikó (, ; born 17 January 1955) is a Hungarian-American biochemist who specializes in ribonucleic acid (RNA)-mediated mechanisms, particularly in vitro-transcribed messenger RNA (mRNA) for protein replacement therapy. Karikó laid the scientific groundwork for mRNA vaccines, overcoming major obstacles and skepticism in the scientific community. Karikó received the Nobel Prize in Physiology or Medicine in 2023 for her work, along with American immunologist Drew Weissman.
Karikó co-founded and was CEO of RNARx from 2006 to 2013. From 2013 to 2022, she was associated with BioNTech RNA Pharmaceuticals, first as a vice president and promoted to senior vice president in 2019. In 2022, she left BioNTech to devote more time to research. In 2021, she received an honorary doctorate from the University of Szeged in Hungary, where she has since become a professor. While Karikó has also been associated with the University of Pennsylvania, which would benefit financially from her eventual discovery, the university had actively discouraged her from pursuing research by underfunding and deprioritizing work on mRNA. After being demoted by the University of Pennsylvania in 1995, Karikó was never granted tenure and joined BioNTech in 2013 after the university had declined to reinstate her.
Karikó's work includes scientific research on RNA-mediated immune activation, resulting in the co-discovery with Drew Weissman of the nucleoside modifications that suppress the immunogenicity of RNA. This is seen as a further contribution to the therapeutic use of mRNA. Together with Weissman, she holds United States patents for the application of non-immunogenic, nucleoside-modified RNA. This technology has been licensed by BioNTech and Moderna to develop their protein replacement technologies, but it was also used for their COVID-19 vaccines.
The messenger RNA-based technology developed by Karikó and the two most effective vaccines based on it, BioNTech/Pfizer and Moderna, have formed the basis for the effective and successful fight against SARS-CoV-2 virus worldwide and have contributed significantly to the containment of the COVID-19 pandemic. For their work, Karikó and Weissman have received numerous other awards besides the Nobel, including the Lasker–DeBakey Clinical Medical Research Award, Time Magazine's Hero of the Year 2021, and the Tang Prize Award in Biopharmaceutical Science in 2022.
Early life and education
Katalin Karikó was born in Szolnok, and grew up in Kisújszállás, Hungary, in a small home without running water, a refrigerator, or television. Her father János was a butcher, and her mother was a bookkeeper. Her father was punished for participating in the revolt of 1956. She excelled in science during her primary education, earning third place in Hungary in a biology competition.
Karikó obtained a BSc degree in biology in 1978 and her PhD in biochemistry in 1982, both from the University of Szeged. She worked with Jenő Tomasz and continued her postdoctoral research at the Institute of Biochemistry, Biological Research Centre (BRC) of Hungary. From 1978 until 1985, she was listed as an intelligence asset by the Communist Hungarian secret police, something she says she was blackmailed into out of fear of repercussions on her career or reprisals against her father. She claims that she did not provide them with information nor was she active as an agent.
In 1985, her lab at the BRC lost its funding, and Karikó sought work at institutions in other countries. After being offered a research position by Robert J. Suhadolnik of Temple University, Karikó left Hungary for the United States with her husband and two-year-old daughter, carrying her daughter's teddy bear stuffed with £900 that they had received from selling their car and exchanging currency on the black market.
Career
Between 1985 and 1988, Karikó was a postdoctoral fellow at Temple University in Philadelphia. Karikó participated in a clinical trial in which patients with AIDS, hematologic diseases, and chronic fatigue syndrome were treated with double-stranded RNA (dsRNA). At the time, this was considered groundbreaking research, as the molecular mechanism of interferon induction by dsRNA was not known, although the antiviral and antineoplastic effects of interferons were well-documented.
In 1988, Karikó accepted a job at Johns Hopkins University without first informing her lab advisor Suhadolnik of her intention to leave Temple, as recounted in Gregory Zuckerman's 2021 book A Shot to Save the World. Suhadolnik told her that if she went to Johns Hopkins, he would have her deported, and subsequently reported her to U.S. immigration authorities, claiming that she was "illegally" in the United States. In the time it took her to successfully challenge the resulting extradition order, Johns Hopkins withdrew the job offer. Suhadolnik "continued bad-mouthing Karikó, making it impossible for her to get a new position" at other institutions, until she met a researcher at Bethesda Naval Hospital who "had his own difficult history with Suhadolnik". Karikó subsequently confirmed that the incident had happened as Zuckerman described, but emphasized that "more importantly I was always grateful to [Suhadolnik for] sending me the IAP66 form in 1985, for the opportunity he gave me to work in his lab", noting that "when I gave a lecture [at Temple, a] couple of years later, I thanked him for the science I learned from him." From 1988 to 1989, she worked at the Uniformed Services University of the Health Sciences in Bethesda, Maryland where she worked with signal protein interferons.
In 1989, she was hired by the University of Pennsylvania to work with cardiologist Elliot Barnathan on messenger RNA (mRNA). In 1990, while an adjunct professor at the Perelman School of Medicine at the University of Pennsylvania, Karikó submitted her first grant application in which she proposed establishing mRNA-based gene therapy. Ever since, mRNA-based therapy has been Karikó's primary research interest. However, in the 1990s, mRNA fell out of favor as many researchers, biotechs, and pharmaceutical companies doubted its potential. Though supported by Elliot Barnathan (who left UPenn in 1997) and David Langer (who then hired her), Karikó found it difficult to gain funding. She was initially on track to become a full professor, but after repeated grant rejections the university demoted her in 1995. Nevertheless, she chose to remain and continue her mRNA research.
In 1997, she met Drew Weissman, a professor of immunology who had recently arrived at the University of Pennsylvania. They began to exchange ideas and then to collaborate. Weissman's funding was critical in helping Karikó to continue and extend her research and the combination of Weissman's immunology and Karikó's biochemistry was extremely effective. They began to move the technology forward, solving problems one at a time, and eventually gaining recognition. Weissman has commented "We had to fight the entire way." Karikó's persistence was noted as exceptional against the norms of academic research work conditions.
Before 2005, a major problem with the proposed therapeutic use of mRNA was that in vivo use led to inflammatory reactions. A key insight came about when Karikó focused on why transfer RNA (tRNA), used as a control in an experiment, did not provoke the same immune reaction as mRNA. A series of landmark studies beginning in 2005 demonstrated that while synthetic mRNA was highly inflammatory, tRNA was noninflammatory. Karikó and Weissman determined how specific nucleoside modifications in mRNA led to a reduced immune response: by replacing uridine with pseudouridine. Their key finding of a chemical modification of mRNA to render it non-immunogenic was rejected by the journals Nature and Science, but eventually accepted by the publication Immunity.
Another important achievement by the researchers was the development of a delivery technique to package the mRNA in lipid nanoparticles, a novel pharmaceutical drug delivery system for mRNA. The mRNA is injected into tiny fat droplets (lipid nanoparticles) which protect the fragile molecule until it can reach the desired area of the body. They demonstrated its effectiveness in animals.
Karikó and Weissman founded a small company, RNARx, and in 2006 and 2013 received patents for the use of several modified nucleosides to reduce the antiviral immune response to mRNA. Soon afterward, the University of Pennsylvania sold the intellectual property license to Gary Dahl, the head of a lab supply company that eventually became Cellscript. Weeks later, Flagship Pioneering, the venture capital company backing Moderna, contacted her in an attempt to license the patent, at which point Karikó had to tell them it was no longer available.
In 2006, Katalin Karikó reached out to biochemist Ian MacLachlan to work with him on the chemically altered mRNA. Initially, MacLachlan and Tekmira turned away from the collaboration. Karikó wanted to team up with Ian MacLachlan because he was the leader of a team that helped advance mRNA technology. Karikó was working on establishing the formulated lipid nanoparticle delivery system that encapsulates mRNA in a dense particle through a mixing process.
In early 2013, Karikó heard of Moderna's $240 million deal with AstraZeneca to develop a Vascular endothelial growth factor mRNA. Karikó realized that she would not get a chance to apply her experience with mRNA at the University of Pennsylvania, so she took a role as vice president at BioNTech RNA Pharmaceuticals (and subsequently became a senior vice president in 2019), while maintaining an adjunct professorship at the University.
As of October 2023, Karikó is a professor at University of Szeged in Hungary.
Scientific contributions
Karikó's research and its specializations have a broad impact with potential implications for areas such as the generation of pluripotent stem cells, and messenger RNA-based gene therapy, as well as "a new class of drugs".
Karikó's work laid the foundation for BioNTech and Moderna to create therapeutic mRNAs that do not induce an immune response. In 2020, Karikó and Weissman's technology was used in vaccines for COVID-19 produced by BioNTech and its partner Pfizer and by Moderna. The mRNA vaccines were developed and approved for use at unprecedented speed, and demonstrated over 90% efficacy. In addition to vaccines for infectious diseases, mRNA has potential applications in treatment of cancer, cardiovascular and metabolic diseases including ischemia. However, in May 2024, a review on the main modification of messengers to lower the immunogenicity of mRNA therapies, i.e. the introduction of N1-methylpseudouridine, a solution that made possible the development of mRNA vaccines against COVID-19, reports that at least in the case of the melanoma vaccine, the introduction of 100% of methylpseudouridines resulted in cancer growth and metastases compared to the unmodified mRNA vaccine.
Awards and honors
Karikó has received more than 130 international awards and honors for her pioneering and globally significant work in biochemistry.
The Nobel Assembly at the Karolinska Institute announced on 2 October 2023 that the 2023 Nobel Prize in Physiology and Medicine was awarded to Katalin Karikó and Drew Weissman for the development of mRNA technology.
Katalin Karikó donated the more than half a million dollars she received from her Nobel Prize to her former alma mater, the University of Szeged on 16 April 2024.
In 2022, Karikó was awarded The Novo Nordisk Prize along with Drew Weissman for their pioneering forces for more than a decade in discovering a nucleoside-modified form of mRNA.
In 2023, Karikó was inducted into the National Inventors Hall of Fame for her research into messenger RNA.
Karikó was named in the 2024 Time 100 influential people in health.
In December 2024, Katalin Karikó was included on the BBC's 100 Women list.
Personal life
Karikó is married to Béla Francia, and they are the parents of two-time Olympic gold medalist rower Susan Francia. Their grandson was born in the U.S. in February 2021 to their daughter and son-in-law, architect Ryan Amos.
Media visibility and memoir
In April 2021, The New York Times featured her career, which laid the groundwork for mRNA vaccines to fight the COVID-19 pandemic.
On 10 June 2021, The Daily podcast from The New York Times highlighted Karikó's career, emphasizing the many challenges she had to overcome before her work was recognized.
In November 2021, the US online publication Glamour named her a Woman of the Year.
In 2023, two children's books were released about her: Never Give Up: Dr. Kati Karikó and the Race for the Future of Vaccines, by Debbie Dadey and Juliana Oakley, and Kati's Tiny Messengers: Dr. Katalin Karikó and the Battle Against COVID-19, by Megan Hoyt and Vivien Mildenberger.
Katalin Karikó's autobiography was published by Crown Publishing Group on 10 October 2023, just days after she won the Nobel Prize. It is titled Breaking Through: My Life in Science. The book became the best-selling non-fiction book in Hungary in 2023, and was awarded the Libri Literary Prize in June 2024. By this time, her memoir had been translated into 9 languages.
Selected publications
See also
Tozinameran – COVID-19 vaccine from Pfizer BioNTech, sold under the brand name Comirnaty
, co-founder of BioNTech
, co-founder of BioNTech
References
External links
1955 births
American Nobel laureates
BioNTech
Hungarian biochemists
Hungarian emigrants to the United States
Hungarian Nobel laureates
Living people
Nobel laureates in Physiology or Medicine
People from Kisújszállás
Recipients of the Lasker–DeBakey Clinical Medical Research Award
Temple University faculty
University of Pennsylvania faculty
University of Szeged alumni
Women biochemists
Women Nobel laureates
Benjamin Franklin Medal (Franklin Institute) laureates
Members of the National Academy of Medicine | Katalin Karikó | [
"Chemistry",
"Technology"
] | 2,950 | [
"Women Nobel laureates",
"Biochemists",
"Women in science and technology",
"Women biochemists"
] |
72,464,813 | https://en.wikipedia.org/wiki/Leticia%20Carigi | María Leticia Carigi Delgado is a Venezuelan astronomer specializing in cosmochemistry, including the overall metallicity of galaxies and galactic halos, and the evolution of galaxies. She works in Mexico as a researcher and professor in the Institute of Astronomy of the National Autonomous University of Mexico (UNAM).
Education and career
Carigi earned master's and doctoral degrees in astronomy through research in Venezuela's Centro de Investigaciones de Astronomia. She completed her Ph.D. in 1994, at the Central University of Venezuela, with the dissertation Evolución química de la vecindad solar con rendimientos químicos estelares dependientes de la metalicidad [Chemical evolution of the solar neighborhood with stellar chemical yields dependant on metallicity], supervised by Gustavo Ramón Bruzual Alfonso.
She came to the UNAM Institute of Astronomy as a postdoctoral researcher, working with Manuel Peimbert, and has been a research professor there since 1995.
Recognition
Carigi is a member of the Mexican Academy of Sciences. In 2010 UNAM gave her their Sor Juana Ines de la Cruz prize.
References
Year of birth missing (living people)
Living people
Astronomers
21st-century Venezuelan scientists
21st-century Venezuelan women scientists
Venezuelan women scientists
Women astronomers
Central University of Venezuela alumni
Academic staff of the National Autonomous University of Mexico
Members of the Mexican Academy of Sciences
Venezuelan chemists
Venezuelan physicists | Leticia Carigi | [
"Astronomy"
] | 293 | [
"Women astronomers",
"Astronomers",
"People associated with astronomy"
] |
72,464,979 | https://en.wikipedia.org/wiki/Amanita%20carneiphylla | Amanita carneiphylla is a species of Amanita found in Western Australia growing among Eucalyptus, Banksia, and Allocasuarina
References
External links
carneiphylla
Fungi of Australia
Fungus species | Amanita carneiphylla | [
"Biology"
] | 46 | [
"Fungi",
"Fungus species"
] |
72,465,013 | https://en.wikipedia.org/wiki/Amanita%20marmorata | Amanita marmorata is a species of Amanita found in South Australia
References
External links
marmorata
Fungi of Australia
Fungus species | Amanita marmorata | [
"Biology"
] | 30 | [
"Fungi",
"Fungus species"
] |
72,465,140 | https://en.wikipedia.org/wiki/GG%20Lupi | GG Lupi is an eclipsing binary star in the southern constellation of Lupus. Most of the time it is a magnitude 5.6 object, making it faintly visible to the naked eye, but during the primary eclipse its brightness falls to 6.1. GG Lupi is located 1/2 degree (one full moon diameter) west of the 3rd magnitude star Delta Lupi.
This star was found to be a spectroscopic binary in 1930, and its eclipses were detected in observations during 1964. Its location in the sky, distance (~490 light years) and proper motion make it a likely member of the Scorpius–Centaurus Association within the Gould's Belt star formation region.
The two stars comprising this binary are both very young main sequence stars of spectral type B. They are estimated to be about 20 million years old, placing them near the zero-age main sequence. Their orbit is somewhat eccentric (e=0.15) and the period of apsidal precession is 102 years.
References
Spectroscopic binaries
Algol variables
135876
74950
Lupi, GG
B-type main-sequence stars
5687
Lupus (constellation) | GG Lupi | [
"Astronomy"
] | 249 | [
"Constellations",
"Lupus (constellation)"
] |
72,466,368 | https://en.wikipedia.org/wiki/Zhang%20Rujing | Zhang Rujing (), alternatively known as Richard Chang Ru-gin, is a Taiwanese businessman and entrepreneur known for founding the largest contract chip manufacturer in mainland China, the Semiconductor Manufacturing International Corporation (SMIC). In mainland China, Zhang is known as "the father of China's foundry industry" and China's "godfather of semiconductors".
Early life and education
Zhang Rujing was born in 1948 in the city of Nanjing, Jiangsu Province (then in the Republic of China) to a steelworker, Zhang Xilun, and his wife Liu Peijin. Less than a year old, Zhang and his family fled with the retreating Kuomintang aboard a boat to Kaohsiung on the southern coast of Taiwan in 1949. Growing up in Kaohsiung, Zhang excelled in his studies and was admitted to study at National Taiwan University (NTU) in the capital, Taipei. After graduating from NTU's Mechanical Engineering Department in 1970, Zhang moved to the United States where he earned his master's degree in engineering from University at Buffalo's School of Engineering and moved to Southern Methodist University in Texas to earn his doctorate in electrical engineering.
Career
In 1977, at 29 years old, Zhang began working at the semi-conductor giant Texas Instruments alongside experts in integrated circuits with his first boss, Nobel Prize in Physics laureate Jack Kilby. Starting as a design engineer, Zhang would then develop under the mentorship of Shao Zifan, and help establish large-scale microchip factories including four in Texas, and others in Italy, Japan, Singapore, and Taiwan. Zhang would bring his then retired parents to the United States from Taiwan. In 1996, leaders from a visiting delegation from the now-defunct Chinese Ministry of Electronics Industry approached Zhang in the United States and, noting China's twenty-year gap in semiconductor manufacture, encouraged Zhang to return to mainland China and help his birth nation establish their own chip fabrication industry. In 1997, after twenty years of work at Texas Instruments, Chang returned to China.
Establishment of SMIC
Returning first to mainland China at age 50, Zhang began searching for locations for a Chinese semiconductor factory. He decided to travel back to Taiwan and founded Shida Semiconductor with the help of his contacts at Texas Instruments. As TSMC expanded in Taiwan, its head, Zhang Zhongmou, convinced TSMC shareholders in 2000 to acquire Shida Semiconductor for $5 billion USD. Zhang Zhongmou, reportedly appreciative of Zhang Rujing's talent and expertise, requested that Zhang Rujing continue to lead Shida Semiconductor, a deal Zhang Rujing accepted on the purported condition that a factory one day be built in mainland China. Learning that Zhang Zhongmou did not intend to establish a factory in mainland China, in 2000, Zhang Rujing resigned, gave up his shares of TSMC, and travelled to the PRC capital of Beijing. Finding neither the city's mayor or vice mayor for science and technology who weren't in the city at that time, Zhang met with Deputy Directory of the Shanghai Economic Commission Jiang Shangzhou who brought Zhang south to Shanghai and introduced him to Zhangjiang Hi-Tech Park. That year, on 3 April 2000, Zhang founded the Semiconductor Manufacturing International Corporation (SMIC). By May, Zhang had recruited hundreds of engineers to Shanghai and construction of the plant began in August 2000. Zhang also moved both his mother (then over 90 years of age) and his American wife to mainland China. Zhang also reportedly built a 1,500 unit housing area for his employees and a bilingual K-12 school for children of employees.
Resignation
Already experienced in the establishment of semiconductor factories, Zhang continued to expand SMIC by building three 8 inch wafer factories in Shanghai, two 12 inch factories in Beijing, and purchased an 8 inch factory in Tianjin from Motorola. In 2002, the Taiwanese government, allegedly feeling pressure from SMIC's primary competitor, TSMC, ordered Zhang to withdraw his investment. After Zhang's refusal, the government fined him 15 million Taiwanese dollars threatening to bring more fines should Zhang not desist. In August 2003, as SMIC planned to launch an IPO in Hong Kong, TSMC sued SMIC in the United States courts for intellectual property theft and patent infringement. In 2005, SMIC was ordered to pay US$175 million to TSMC in damages, surrender TSMC documents, and halt the use of TSMC technology and processes in SMIC's fabrication. Later, in a separate lawsuit, a California jury would find that SMIC breached the terms of the 2005 settlement by not returning documents and disclosing TSMC trade secrets in patent applications. Along with a compensation of $200 million USD and 10% equity given by SMIC to TSMC in 2009, Zhang, then 61, was prohibited from operating in the chip industry for a period of three years.
Later life
In 2014, having passed his three-year prohibition from the semiconductor industry, a 66-year-old Zhang founded Shanghai Xinsheng, the first 300 mm large silicon wafer company in mainland China. In 2018, Zhang established SiEn (Qingdao) Integrated Circuits which, in 2021, began producing 8 inch silicon wafers and was testing 12 inch production. Zhang has continued to play an active role in the advocacy of the People's Republic of China's chip industry. Zhang has expressed his confidence that China would catch up to global leaders in the industries of third-generation gallium nitride (GaN) and silicon carbide (SiC) semiconductors. SiEn, meanwhile, has discussed potential partnerships with Huawei Technologies to allow access to semiconductor development services in what the Japanese Financial Newspaper Nikkei asserts is an attempt "to plug holes in its semiconductor supply chain caused by the U.S. crackdown on the tech giant".
References
1948 births
Businesspeople from Nanjing
Texas Instruments people
Living people
Taiwanese company founders
20th-century Taiwanese businesspeople
21st-century Taiwanese businesspeople
Businesspeople from Jiangsu
University at Buffalo alumni
Southern Methodist University alumni
National Taiwan University alumni
Electrical engineers | Zhang Rujing | [
"Engineering"
] | 1,234 | [
"Electrical engineering",
"Electrical engineers"
] |
72,468,219 | https://en.wikipedia.org/wiki/Bexagliflozin | Bexagliflozin, sold under the brand name Brenzavvy, is an antidiabetic medication used to improve glycemic control in adults with type 2 diabetes. It is a sodium-glucose cotransporter 2 (SGLT2) inhibitor that is taken by mouth.
The most common side effects include genital yeast infections, urinary tract infections, and increased urination.
Bexagliflozin was approved for medical use in the United States in January 2023.
Medical uses
Bexagliflozin is indicated to improve glycemic control in adults with type 2diabetes in combination with diet and exercise.
Adverse effects
Bexagliflozin may cause ketoacidosis, a serious, potentially life-threatening complication that occurs when the body produces high levels of acids in the blood. Bexagliflozin may also cause serious side effects such as an increased incidence for surgery to remove parts of the legs or feet, decreases in blood pressure due to excessive loss of water and sodium from the body, serious infections in the genital region (Fournier’s gangrene), very low blood sugar levels when used in combination with insulin or medications that increase insulin in the body, and serious urinary tract infections.
History
The US Food and Drug Administration (FDA) approved bexagliflozin based on evidence from nine clinical trials that enrolled 4,462 adults (2,578 of these participants received bexagliflozin). The nine trials were conducted at 428 sites in 16 countries including the United States, Mexico, Colombia, Japan, the Czech Republic, Poland, Spain, Hungary, France, Canada, Netherlands, Denmark, South Korea, Taiwan, Russia, and Germany. All nine trials were used to assess safety and six of these trials (enrolling 3,346 participants of the 4,462 participants) were used to assess the efficacy of bexagliflozin. The efficacy of bexagliflozin was evaluated in six clinical trials, while the safety of bexagliflozin was evaluated in nine clinical trials of adults with type2 diabetes whose blood sugar was not well controlled. All participants were required to follow diet and exercise recommendations, but the trials differed with respect to which other drugs participants were allowed to use for diabetes treatment. In four trials, participants were randomly assigned to receive either bexagliflozin or placebo by mouth once daily. In two trials, they received either bexagliflozin or a different diabetes medicine. Neither the participants nor the healthcare providers knew which treatment participants received until after the trial was completed. The benefit of bexagliflozin was evaluated by the change in hemoglobin A1c (HbA1c) between the bexagliflozin and the comparator (either placebo or another diabetes medicine) at the end of the treatment period.
Society and culture
Legal status
Bexagliflozin was approved for medical use in the United States in January 2023.
Research
A 96-week phase II clinical study of adults with type2 diabetes showed that bexagliflozin monotherapy provided a durable, clinically meaningful improvement of glycemic control, with a substantial reduction in weight and blood pressure, but no increase in the rate of significant adverse events. In a clinical study of patients with type 2 diabetes and stage 3a/3b chronic kidney disease, bexagliflozin was well tolerated and shown to reduce hemoglobin A1c levels, body weight, systolic blood pressure and albuminuria.
Veterinary uses
The data from two six-month field studies and an extended use field study demonstrated that bexagliflozin was over 80% effective in improving glycemic control in cats with diabetes mellitus.
Bexagliflozin, sold under the brand name Bexacat, is an antidiabetic medication used to improve glycemic control in cats with diabetes. Bexacat is the first sodium-glucose cotransporter 2 (SGLT2) inhibitor new animal drug approved by the US Food and Drug Administration (FDA) in any animal species. It was approved for medical use in the United States in December 2022. Bexacat is sponsored by Increvet Inc., based in Boston, Massachusetts. Elanco licensed development and commercialization rights for bexagliflozin from Bexcafe, an affiliate of Increvet.
References
Further reading
External links
Cat medications
SGLT2 inhibitors
Chloroarenes
Cyclopropyl compounds
Ethers
Phenol ethers
Glucosides | Bexagliflozin | [
"Chemistry"
] | 960 | [
"Organic compounds",
"Functional groups",
"Ethers"
] |
72,471,531 | https://en.wikipedia.org/wiki/Insectoid%20robot | An insectoid robot is a, usually small, robot featuring some insect-like features. These can include the methods of locomotion (including flying), methods of navigation, and artificial intelligence based on insect models. Many of the problems faced by miniature robot designers have been solved by insect evolution. Researchers naturally look to insects for inspiration and solutions.
Locomotion
Walking
Robot locomotion has frequently been inspired by insect physiology. These robots typically take the form of a hexapod. Research has become multidisciplinary, involving not only robotics engineers, but also biologists, especially neurobiologists. Engineers gain from thisrelationship by acquiring a better understanding of the functioning of the insects they have used to model their robots. Biologists in turn, gain a platform on which they can test their theories of insect motor control.
Building a robot that can walk on a flat surface in the laboratory is a fairly straightforward task. A hexapod robot with mechanically linked simple pegs for legs will achieve this task. Then again, a wheeled robot might be even simpler, but may be entirely unable to solve the much more difficult problem of crossing rough terrain with unpredictable obstacles. For this, articulated joints in legs like a real insect, with sensor-motor control like the neurology of a real insect are needed. A simple rhythmic cycle of the legs will not do. The legs and joints must be controlled individually and in combination according to information received from limb position and load sensors.
The gait of insects changes with desired speed. Research has shown that these gait patterns can still be generated locally in many insects even when completely disconnected from the central nervous system. In some insects, for instance the cockroach, the gait changes in a running insect partly because the nervous system of the insect cannot respond rapidly enough. A running cockcroach changes its gait to pushing with all three legs on one side together. The characteristic side-to-side motion of the animal is at the biomechanical resonant frequency set by the insect's weight and spring stiffness of the combined legs. This mode needs no input from an external controller and it is both efficient and stable. Researchers recognise the advantages of features of real insects, but as of 2004, "they have only rarely come together in a robot..."
Flying
For a very small aircraft, fixed-wing flight becomes impractical due to rapidly decreasing lift-to-drag ratio with size. Insect flight, on the other hand, is always ornithopteric which suggests an approach for insectoid robots. Ma et al. for instance, developed a tethered robot fly with flapping wings constructed of piezoelectric material. Ma chose to model the robot on the fly because, according to their paper, it is the most agile creature alive, and therefore the most difficult to emulate as a robot.
Artificial intelligence
Insects have very little resource to devote to intelligence in the human sense of brain processing power. The number of neurons in an insect varies by species from one million to as few as ten thousand. By comparison, humans have 86 billion neurons. Further, large brains are extremely energy hungry. Insects must therefore find other methods of developing intelligence such as embodying intelligence in hardware, local sensor-motor connections, and swarm intelligence. At one time it was hoped that robots would avoid the need for such solutions because of the rapidly increasing processing power and decreasing size of computers according to Moore's law. However, this process seems to be reaching its limit and insect solutions look increasingly attractive.
Walking rhythms independent of the central nervous system in cockroaches have already been mentioned. A major breakthrough in flying insectoid robots came by applying the same principles to the wings. Attempts to control the angle of attack of the wings with a central processor were not successful because a lift to weight ratio greater than unity could not be achieved. Removing the processor and allowing the wings to rotate passively at the natural frequency of the mechanical system reduced the weight sufficiently to allow controlled insectoid flight for the first time in 2008 with a fly-like robot. However, the robot was externally powered through an umbilical rather than completely free flight.
Swarms of robots can solve problems that are not possible to solve with the limited processing resource of a single robot. They are particular useful in exploration tasks. They can be used to find the shortest route to a destination, and have been proposed to search for gas sources in dangerous environments. Another proposal is robots that self-assemble into a structure to allow the swarm to cross a gap in the manner of ants.
Navigation
Flying insects have poor visual spatial resolution, must respond rapidly, and have little to no advanced neural processing power. Due to limitations of space and weight, flying insectoid robots have a very similar set of problems. In 2003, Franceschini et al. investigated the possibility of using insect solutions to solve robot navigation problems. Franceschini built a research robot based on the neural physiology of a fly. The robot was not actually a flying robot, rather, it was a wheeled vehicle. The aim of the research was to show that simple sensor-motor control using only visual motion detection could navigate a course.
Using insect intelligence in robot navigation has been going on since 1986, but initially was not taken up by engineers building robots. It was felt that because insects lack a visual cortex, and hence cannot perform advanced visual processing and image formation, a robot based on such technology would not be very successful. Franceschini argues that it is not necessary to possess a visual cortex for the navigation task, and it would in fact be an unnecessary burden on an insect robot (both weight and processing time would be issues). Franceschini points out that many of the visual systems in humans do not pass through the visual cortex either. It is not always necessary to form images and identify objects.
See also
Materially engineered artificial pollinators
RoboBee
References
Bibliography
G.C.H.E. de Croon, J.J.G. Dupeyroux, S.B. Fuller, J. A. R. Marshall, "Insect-inspired AI for autonomous robots", Science Robotics, vol. 7, no. 67, 2022 .
Fred Delcomyn, "Insect walking and robotics", Annual Review of Entomology, vo. 49, pp. 51–70, 2004.
N. Franceschini, J. M. Pichon, C. Blanes, "From insect vision to robot vision", Philosophical Transactions of the Royal Society B, vol. 337, iss. 1281, 29 September 1992 .
Kevin Y. Ma, Pakpong Chirarattananon, Sawyer B. Fuller, and Robert J. Wood, "Controlled flight of a biologically inspired, insect-scale robot", Science, vol. 340, iss. 6132, pp. 603–607, 3 May 2013 .
Bradley Voytek, "Are there really as many neurons in the human brain as stars in the Milky Way?", Scitable, 20 May 2013.
Robert J. Wood, "The first takeoff of a biologically inspired at-scale robotic insect", IEEE Transactions on Robotics, vol. 24, iss. 2, pp. 341–347, April 2008 .
Robots
Insects and humans | Insectoid robot | [
"Physics",
"Technology"
] | 1,491 | [
"Physical systems",
"Machines",
"Robots"
] |
72,472,311 | https://en.wikipedia.org/wiki/NGC%207454 | NGC 7454 is an elliptical galaxy in the constellation Pegasus. It was discovered on October 15, 1784 by William Herschel. This object has an apparent visual magnitude of 11.8, a visual size of , and a morphological classification of E4. J. L. E. Dreyer described the galaxy as F, cS, lE, lbM, *11 p 1', which indicates it is faint, considerably small, a little extended, with a little brighter middle, and an 11th magnitude star is located 1 arcmin to west.
References
External links
Pegasus (constellation)
7454
Elliptical galaxies
12305
70264
Astronomical objects discovered in 1784
Discoveries by William Herschel | NGC 7454 | [
"Astronomy"
] | 138 | [
"Pegasus (constellation)",
"Constellations"
] |
72,473,286 | https://en.wikipedia.org/wiki/Pseudotricholoma%20metapodium | Pseudotricholoma metapodium is a species of agaric (gilled mushroom) in the family Tricholomataceae. It has been given the recommended English name of mealy meadowcap. The species has a European distribution, occurring mainly in agriculturally unimproved grassland. Threats to its habitat have resulted in the mealy meadowcap being assessed as globally "endangered" on the IUCN Red List of Threatened Species.
Taxonomy
The species was first described by Swedish mycologist Elias Magnus Fries in 1818 as Agaricus metapodius. Rolf Singer transferred it to Porpoloma in 1973, but subsequent molecular research, based on cladistic analysis of DNA sequences, found that the latter genus was polyphyletic with species belonging either to Porpoloma sensu stricto or the new genus Pseudotricholoma.
Description
Basidiocarps are agaricoid, up to 90 mm (3.5 in) tall, the cap convex then flat, up to 100 mm (4 in) across. The cap surface is smooth, pale to dark grey-brown to reddish brown, often splitting at margin. The lamellae (gills) are very pale grey to brownish, bruising red then black. The stipe (stem) is smooth, finely fibrillose, similarly coloured to the pileus or paler, slowly bruising red then black, lacking a ring. The smell is mealy when cut. The spore print is white, the spores (under a microscope) ellipsoid to oblong, amyloid, measuring about 6 to 8 by 3 to 4 μm.
Similar species
In grassland, the common Lepista luscina can look similar, but is typically paler, does not change colour when bruised, and is microscopically distinct. The rare Neohygrocybe ovina does bruise red, but is typically blacker and is also microscopically distinct.
Distribution and habitat
The mealy meadowcap is rare but widespread in northern and central Europe. It occurs in old, agriculturally unimproved, short-sward grassland (pastures and lawns).
Conservation
Pseudotricholoma metapodium is typical of waxcap grasslands, a declining habitat due to changing agricultural practices. As a result, the species is of global conservation concern and is listed as "endangered" on the IUCN Red List of Threatened Species.
References
Fungi described in 1818
Fungi of Europe
Tricholomataceae
Taxa named by Elias Magnus Fries
Fungus species | Pseudotricholoma metapodium | [
"Biology"
] | 506 | [
"Fungi",
"Fungus species"
] |
72,475,009 | https://en.wikipedia.org/wiki/Mycena%20indigotica | Mycena indigotica is a species of fungus. It was described for the first time in 2018 by Chia Ling Wei and Roland Kirschner after its discovery on the North-western Pacific Island of Taiwan. The genus Mycena is most famous for containing the majority of described bioluminescent fungi. However, M. indigotica is one of the many non-bioluminescent species within the genus. Nonetheless, this mushroom is aesthetically striking, with a petite and novel morphology.
Taxonomy and phylogeny
Mycena indigotica was first described by Wei and Kirschner from Taiwan in 2019, making it a relatively newly described species. The specific epithet “indigotica” is a homage to the historical industry of indigo dying in Taiwan. The closet relative is purported to be Mycena illuminans. This is interesting and worth consideration, as M. illuminans possesses bioluminescence traits while M. indigotica does not. It is possible that the species exhibits cryptic bioluminescent traits, something that has been noted in other Mycena species before. What is more likely to have occurred however, is a loss of function within the luciferase producing genes of the species. This is supported in a recent study where M. indigotica was used in a to describe the origin of bioluminescence in fungal species. M. indigotica was selected for its lack of apparent bioluminescent features. Results from the study support the idea that M. indigotica lost the entirety of the luciferase gene cluster from its genome.
Morphology
Morphologically the species is quite striking. The following is an excerpt from the descriptive paper on the species:
"Basidiomata gregarious, not luminescent. Pileus 1.5-3.5 mm diam, at first semiglobose, then convex to flattened, non-striate, pale blue… to blue…when young, gradually with black tints with age, totally black when old or in dried specimens, slightly pruinose when young, glabrous with age, context white, margin entire, crenulate. Hymenophore consisting of 70-120 pores, pores circular, usually oval near stipe, concolorous with surface of pileus, 8-12 pores per mm. Stipe 2e4 x 0.5e1 mm, blue…to dark blue…gradually with black tints with age, pruinose when young, glabrous with age, cylindrical, central, basally bulbous".
Additionally, the basidiospore morphology is globose to ellipisoid. Multiple cystidia cell types are reported (cheilo-, pleuro-, and caulo-), which is an important feature for identification of many Mycena individuals to species. Exceptional illustrations of microscopic features can be found within the descriptive paper. From available pictures, the species seems to invert the pilus and expose the hymenium, possibly a method for more efficient spore dispersal.
Ecology
Ecologically, the species seems to be a saprotrophic wood decaying fungus, which is in concordance with the majority of other species in the genus. The species was observed on a substrate of fallen Calamus sp. These were located within the lowland valleys of Taiwan near the city of New Taipei. The fungus was observed in all seasons except for the winter. This may suggest the utilization of survival structures by the genus that have not yet been noted or that this species fruits preferentially during warm weather. This species is currently only known from Northern Taiwan. The closest purported relative M. illuminans was originally collected on the Indonesian island of Java, a significant distance away from Taiwan (> 2000 miles).
References
indigotica
Fungi described in 2018
Fungi of Asia
Fungus species | Mycena indigotica | [
"Biology"
] | 787 | [
"Fungi",
"Fungus species"
] |
72,476,496 | https://en.wikipedia.org/wiki/Hegerfeldt%27s%20theorem | Hegerfeldt's theorem is a no-go theorem that demonstrates the incompatibility of the existence of spatially localized discrete particles with the combination of the principles of quantum mechanics and special relativity. A crucial requirement is that the states of single particle have positive energy. It has been used to support the conclusion that reality must be described solely in terms of field-based formulations. However, it is possible to construct localization observables in terms of positive-operator valued measures that are compatible with the restrictions imposed by the Hegerfeldt theorem.
Specifically, Hegerfeldt's theorem refers to a free particle whose time evolution is determined by a positive Hamiltonian. If the particle is initially confined in a bounded spatial region, then the spatial region where the probability to find the particle does not vanish, expands superluminarly, thus violating Einstein causality by exceeding the speed of light. Boundedness of the initial localization region can be weakened to a suitably exponential decay of the localization probability at the initial time. The localization threshold is provided by twice the Compton length of the particle. As a matter of fact, the theorem rules out the Newton-Wigner localization.
The theorem was developed by Gerhard C. Hegerfeldt and first published in 1974.
See also
Wave–particle duality
Local realism
References
No-go theorems
Quantum field theory
Theory of relativity
Theorems in quantum mechanics | Hegerfeldt's theorem | [
"Physics",
"Mathematics"
] | 291 | [
"Theorems in quantum mechanics",
"Quantum field theory",
"No-go theorems",
"Equations of physics",
"Quantum mechanics",
"Theorems in mathematical physics",
"Theory of relativity",
"Physics theorems"
] |
72,477,621 | https://en.wikipedia.org/wiki/Diversity%20%28mathematics%29 | In mathematics, a diversity is a generalization of the concept of metric space. The concept was introduced in 2012 by Bryant and Tupper,
who call diversities "a form of multi-way metric". The concept finds application in nonlinear analysis.
Given a set , let be the set of finite subsets of .
A diversity is a pair consisting of a set and a function satisfying
(D1) , with if and only if
and
(D2) if then .
Bryant and Tupper observe that these axioms imply monotonicity; that is, if , then . They state that the term "diversity" comes from the appearance of a special case of their definition in work on phylogenetic and ecological diversities. They give the following examples:
Diameter diversity
Let be a metric space. Setting for all defines a diversity.
L diversity
For all finite if we define then is a diversity.
Phylogenetic diversity
If T is a phylogenetic tree with taxon set X. For each finite , define
as the length of the smallest subtree of T connecting taxa in A. Then is a (phylogenetic) diversity.
Steiner diversity
Let be a metric space. For each finite , let denote
the minimum length of a Steiner tree within X connecting elements in A. Then is a
diversity.
Truncated diversity
Let be a diversity. For all define
. Then if , is a diversity.
Clique diversity
If is a graph, and is defined for any finite A as the largest clique of A, then is a diversity.
References
Metric spaces | Diversity (mathematics) | [
"Mathematics"
] | 303 | [
"Mathematical structures",
"Space (mathematics)",
"Metric spaces"
] |
72,480,205 | https://en.wikipedia.org/wiki/J%C3%BCrgen%20Kirschner | Jürgen Kirschner (born April 18, 1945) is a German solid state physicist and a director at the Max Planck Institute of Microstructure Physics. Kirschner is known for his research in electron spectroscopy, including instrument development and the study of magnetic materials.
Education and career
Kirschner was born in Arendsee (Altmark) and studied physics at Technical University of Munich, where he obtained his PhD in 1974. He followed with research position at Forschungszentrum Jülich and obtained his habilitation at RWTH Aachen University in 1982. From 1988 to 1991, he was a professor in experimental physics at the Free University of Berlin. From 1992 to 2015, he was at the Max Planck Institute of Microstructure Physics in Halle, where he also became a professor at the University of Halle since 1993. He retired in 2015.
Honors and awards
Kirschner is a member of the German National Academy of Sciences Leopoldina since 2002. He has led several programs from the German Research Foundation.
Bibliography
References
1945 births
People from Altmarkkreis Salzwedel
Technical University of Munich alumni
Academic staff of RWTH Aachen University
Academic staff of the Free University of Berlin
Academic staff of the University of Halle
Max Planck Institute directors
Max Planck Society people
German experimental physicists
Condensed matter physicists
German materials scientists
Members of the German National Academy of Sciences Leopoldina
Living people | Jürgen Kirschner | [
"Physics",
"Materials_science"
] | 282 | [
"Condensed matter physicists",
"Condensed matter physics"
] |
72,480,760 | https://en.wikipedia.org/wiki/Nissim%20Benvenisty | Nissim Benvenisty is Professor of Genetics, the Herbert Cohn Chair in Cancer Research and the Director of “The Azrieli Center for Stem Cells and Genetic Research” at the Alexander Silberman Institute of Life Sciences, Hebrew University.
Benvenisty earned his M.D. and Ph.D. degrees from the Hebrew University, and conducted postdoctoral fellowship at Harvard University. He is a member of the steering committee of the International Stem Cell Initiative (ISCI), the Programme Board of the UK-RMP, and serves as the academic advisor for the International Society for Stem Cell Research (ISSCR). He is a founding member of the Israel Stem Cell Society, and he is the Founder and CSO of NewStem Ltd.
Research
Benvenisty’s research projects focus on pluripotent stem cell biology, human genetic disorders, tissue engineering, genetic and epigenetic aberrations and cancer research. His laboratory made several contributions in these fields of research:
Differentiation and genetic manipulation of human embryonic stem cells: In 2000, his laboratory pioneered the first demonstration of both spontaneous differentiation of human embryonic stem cells into embryoid bodies and direct differentiation into more than ten cell types. In addition, his laboratory was the first to demonstrate genetic manipulation of human embryonic stem cells. These discoveries where highlighted by a Focus article in “Science”.
Disease modelling using human pluripotent stem cells: Benvenisty’s laboratory was the first to show a model for a human disease using human pluripotent stem cells. Since then he has demonstrated six methodologies to generate models for genetic disorders, generating more than a dozen models for studying mainly neural diseases (such as Fragile X syndrome) and imprinting disorders (such as Prader-Willi syndrome).
Tumorigenicity and immunogenicity of human pluripotent stem cells: Immunogenicity and tumorigenicity of human pluripotent stem cells are very relevant for the safe and efficient use of these cells in regenerative medicine. Benvenisty’s laboratory was the first to study the immunogenicity of the cells, and to analyze the basis of their tumorigenicity.
Genetic and epigenetic stability of human pluripotent stem cells: The genetic and epigenetic instability of human pluripotent stem cells is a major characteristic of the cells affecting their tumorigenicity and their use in disease modeling. Benvenisty’s lab was the first to study the chromosomal stability of human induce pluripotent stem cells, and developed methodologies to analyze genetic and epigenetic aberrations.
Haploid human embryonic stem cells and genome-wide screenings: Benvenisty’s lab was the first to generate haploid human embryonic stem cells (having half of the chromosomes). His laboratory utilized these cells for genome-wide genetic screenings to analyze human development and disease.
Benvenisty's lab serves as an incubator for excellent students, and over ten of his former students hold principal investigator positions in the Israeli academia (Hebrew University, Weizmann Institute, Tel-Aviv University, Bar-Ilan University, Technion).
Awards and honors
The Rappaport Prize for excellence in the field of biomedical research (2023)
The Katzir Prize (2020) for exceptional achievements in life sciences, given triennial by FISEB/ILANIT.
Awarded Member of Academia Europaea (2018).
The ACTO Prize (Japan) (2018) for “Best Innovation in Stem Cell Research”.
Milken Prize for Excellent Teachers, Hebrew University (2016).
Awarded the “Azrieli Center for Stem Cells and Genetic Research” by the Azrieli Foundation (Canada) (2014).
Kaye Prize for best innovation (2010).
Awarded the “Legacy-Heritage Stem Cell Center” (USA) (2006).
Yamagiwa-Yoshida Memorial International Cancer Study Fellowship (Japan) (2000).
Hestrin Prize in Biochemistry and Molecular Biology (1997).
Senta Foulkes Prize (London).
References
External links
Benvenisty lab's website
Benvenisty's lab at the Alexander Silberman Institute of Life Sciences
Nissim Benvenisty publications indexed by Google Scholar
Academic staff of the Hebrew University of Jerusalem
Harvard University faculty
Stem cell researchers
Year of birth missing (living people)
Living people | Nissim Benvenisty | [
"Biology"
] | 908 | [
"Stem cell researchers",
"Stem cell research"
] |
72,481,180 | https://en.wikipedia.org/wiki/NGC%203435 | NGC 3435 is a barred spiral galaxy located about 235 million light-years from the Milky Way, and is about 125 000 light-years across. It can be found in the constellation Ursa Major. It was discovered on 9 April 1793 by astronomer William Herschel.
The galaxy has the surface brightness equal to 14.04 mag/Minute and second of arcam², which classifiers it as low surface brightness galaxy (LSB).
Supernova
On 29 March 1999, in the galaxy was observed the type Ia supernova, designated as SN 1999bh. It was discovered by W. Li, as part of the Lick Observatory Supernova Search (LOSS) program by the Lick Observatory.
References
External links
Barred spiral galaxies
Ursa Major
3454
6025
32786
Astronomical objects discovered in 1793
Interacting galaxies | NGC 3435 | [
"Astronomy"
] | 164 | [
"Ursa Major",
"Constellations"
] |
72,482,500 | https://en.wikipedia.org/wiki/Subdivision%20%28simplicial%20complex%29 | A subdivision (also called refinement) of a simplicial complex is another simplicial complex in which, intuitively, one or more simplices of the original complex have been partitioned into smaller simplices. The most commonly used subdivision is the barycentric subdivision, but the term is more general. The subdivision is defined in slightly different ways in different contexts.
In geometric simplicial complexes
Let K be a geometric simplicial complex (GSC). A subdivision of K is a GSC L such that:
|K| = |L|, that is, the union of simplices in K equals the union of simplices in L (they cover the same region in space).
each simplex of L is contained in some simplex of K.
As an example, let K be a GSC containing a single triangle {A,B,C} (with all its faces and vertices). Let D be a point on the face AB. Let L be the complex containing the two triangles {A,D,C} and {B,D,C} (with all their faces and vertices). Then L is a subdivision of K, since the two triangles {A,D,C} and {B,D,C} are both contained in {A,B,C}, and similarly the faces {A,D}, {D,B} are contained in the face {A,B}, and the face {D,C} is contained in {A,B,C}.
Subdivision by starring
One way to obtain a subdivision of K is to pick an arbitrary point x in |K|, remove each simplex s in K that contains x, and replace it with the closure of the following set of simplices:where is the join of the point x and the face t. This process is called starring at x.
A stellar subdivision is a subdivision obtained by sequentially starring at different points.
A derived subdivision is a subdivision obtained by the following inductive process.
Star each 1-dimensional simplex (a segment) at some internal point;
Star each 2-dimensional simplex at some internal point, over the subdivision of the 1-dimensional simplices;
... Star each k-dimensional simplex at some internal point, over the subdivision of the (k-1)-dimensional simplices.
The barycentric subdivision is a derived subdivision where the points used for starring are always barycenters of simplices. For example, if D, E, F, G are the barycenters of {A,B}, {A,C}, {B,C}, {A,B,C} respectively, then the first barycentric subdivision of {A,B,C} is the closure of {A,D,G}, {B,D,G}, {A,E,G}, {C,E,G}, {B,F,G}, {C,F,G}.
Iterated subdivisions can be used to attain arbitrarily fine triangulations of a given polyhedron.
In abstract simplicial complexes
Let K be an abstract simplicial complex (ASC). The face poset of K is a poset made of all nonempty simplices of K, ordered by inclusion (which is a partial order). For example, the face-poset of the closure of {A,B,C} is the poset with the following chains:
{A} < {A,B} < {A,B,C}
{A} < {A,C} < {A,B,C}
{B} < {A,B} < {A,B,C}
{B} < {B,C} < {A,B,C}
{C} < {A,C} < {A,B,C}
{C} < {B,C} < {A,B,C}
The order complex of a poset P is an ASC whose vertices are the elements of P and whose simplices are the chains of P.
The first barycentric subdivision of an ASC K is the order complex of its face poset. The order complex of the above poset is the closure of the following simplices:
{ {A} , {A,B} , {A,B,C} }
{ {A} , {A,C} , {A,B,C} }
{ {B} , {A,B} , {A,B,C} }
{ {B} , {B,C} , {A,B,C} }
{ {C} , {A,C} , {A,B,C} }
{ {C} , {B,C} , {A,B,C} }
Note that this ASC is isomorphic to the ASC {A,D,G}, {B,D,G}, {A,E,G}, {C,E,G}, {B,F,G}, {C,F,G}, with the assignment: A={A}, B={B}, C={C}, D={A,B}, E={A,C}, F={B,C}, G={A,B,C}.
The geometric realization of the subdivision of K is always homeomorphic to the geometric realization of K.
Simplicial sets
References | Subdivision (simplicial complex) | [
"Mathematics"
] | 1,170 | [
"Basic concepts in set theory",
"Families of sets",
"Simplicial sets"
] |
72,482,510 | https://en.wikipedia.org/wiki/Poecilobothrus%20majesticus | Poecilobothrus majesticus is an extinct species of fly in the family Dolichopodidae that was endemic to Great Britain. The species is known from a single male specimen collected near the Essex coast in Walton-on-the-Naze in 1907, and it was formally described by E. C. M. d'Assis-Fonseca in 1976. It has not been recorded for over 100 years, so it is therefore considered to be extinct.
History of research
The holotype and only known specimen of P. majesticus, an adult male, was collected from Walton-on-the-Naze in 1907. Many years later, D'Assis-Fonseca rediscovered this specimen deposited in the Oxford University Museum of Natural History, in the Verrall-Collin collection of the Hope Department. In 1976, D'Assis-Fonseca published a formal description of a new species based on the specimen, named Poecilobothrus majesticus. He reported that it had a label identifying it as Poecilobothrus bigoti, but stated that it didn't fit Josef Mik's original description of that species. He also stated that the only Palaearctic species of Poecilobothrus that the specimen resembled was Poecilobothrus basilicus, but that it differed enough from it to be considered a distinct species.
A 2018 report reviewing the conservation status of Dolichopodidae in Great Britain concluded that P. majesticus was "Regionally Extinct", justifying the status by stating that the species had not been recorded for over 100 years despite the recording effort within the Essex coast. In 2022, the species was classified on the IUCN Red List as extinct.
References
Dolichopodinae
Insects described in 1976
Extinct insects since 1500
Endemic fauna of England
Extinct animals in the United Kingdom
Species known from a single specimen | Poecilobothrus majesticus | [
"Biology"
] | 392 | [
"Individual organisms",
"Species known from a single specimen"
] |
72,482,743 | https://en.wikipedia.org/wiki/Toilets%20in%20New%20York%20City | New York City contains approximately 1,100 publicly managed toilets, as well as an unknown number of privately owned toilets. As of 2017, there were around 3.5 million housing units in New York City (many with toilets), while private toilets also exist in offices and other non-residential establishments.
Compared to other big cities, public bathrooms in New York City are rare, as the 1,100 public restrooms result in a rate of 16 per 100,000 residents. Most public restrooms are located in parks; comparatively few other public spaces, including New York City Subway stations, have public restrooms. There have been several attempts to install pay toilets in New York City since the 1990s, and five pay toilets have been installed as part of a program launched in 2006. The cost to build public toilets varies widely, but they averaged $3.6 million .
During the mid-19th century, prior to the advent of indoor plumbing and flush toilets, buildings and homes used outhouses and chamber pots as toilets. Proper plumbing was only mandated under the New York State Tenement House Act of 1901.
Types
Flush toilets in New York City private residences are commonplace, though urinals are also common throughout New York City bathrooms, typically in the modern design. There are a number of bars in New York City, including McSorley's Old Ale House, that feature large vintage urinals. The oldest urinal in the city is allegedly located at the Old Town Bar in the Flatiron District.
History
As flush toilets were rarely used in Europe before the 19th century, New Amsterdam's first settlers instead brought with them the outhouse custom. During the mid-19th century, prior to the advent of indoor plumbing and flush toilets, buildings and homes were equipped with outhouses and chamber pots. In addition, both poor and rich residents used privy vaults. In the late 19th century, many tenements in New York City, particularly on the Lower East Side, lacked toilets or running water.
Proper plumbing was only mandated by the New York State Tenement House Act of 1901. At that point, New York City's tenements had more than 9,000 privy vaults, euphemistically referred to as "school sinks", in their courtyards. The school sinks were only flushed into the city's primitive sewerage system occasionally and were major vectors for diseases. The 1901 law banned these school sinks and required landlords to replace them with toilets. Afterward, many landlords began installing toilets and bathtubs for their tenants. By 1914, there were only 375 remaining school sinks.
The average New York City resident did not have indoor toilets until the late 19th century. Advancements in plumbing technology allowed for the affordability and installation of toilets in middle-class homes.
As part of the 1968 Building Code of the City of New York, buildings were required to have at least one bathroom per sex per 100 people. This was changed to one bathroom per sex per 150 people in the 2008 Building Code.
In 2012, mayor Michael Bloomberg signed legislation that permitted small restaurants with a capacity of up to 30 people to provide one restroom, rather than the two restrooms required in most establishments. The administration of mayor Eric Adams modified the city's building code in 2022 so that restaurants were no longer obligated to open their restrooms to the general public.
Public access
Finding a public bathroom in New York City is notoriously difficult. A report issued by the New York City Comptroller's Office in 2019 noted that, of the 100 largest cities in the United States, New York ranked 93rd in the number of comfort stations per 100,000 residents. This equated to only 16 public restrooms per 100,000 residents, compared to 210 in Saint Paul, Minnesota, and 140 in Jacksonville, Florida. The dearth of public toilets has prompted residents to create maps of public restrooms in New York City. Clyde Haberman wrote for The New York Times in 2000: "The fact remains that this is one of the few great world cities that make no attempt to help people cope with so basic a need, a situation that constantly amazes residents and visitors alike." According to Aaron Elstein of Crain's New York, the shortage of public restrooms dates to the 1975 New York City fiscal crisis, when the city government attempted to save money by shutting public restrooms. Homeless New Yorkers reported that the COVID-19 pandemic made it even more difficult to find bathrooms.
, the New York City Subway has 472 stations, 69 of which have public bathrooms. Several homeless people sued the New York City government and the Metropolitan Transportation Authority (MTA) in 1990, claiming that the city and MTA created a "public nuisance" by failing to provide public toilets. A report by the Legal Action Center for the Homeless, who represented the plaintiffs, noted that of 526 public comfort stations surveyed in parks, almost three-quarters were "either closed, filthy, foul-smelling or without toilet paper and soap." In 2010, there were 133 open restrooms in 81 of the system's 468 stations.
According to Bloomberg News, there are about 1,103 public bathrooms in New York City, while The New York Times cites the city as having 1,160 public restrooms. Most are in parks, with municipal facilities such as libraries and swimming pools also being common locations. The public bathrooms in Bryant Park, located between 40th and 42nd streets in Manhattan, are noted for their particular beauty and architectural significance. There have also been temporary public bathrooms. For example, toilet paper brand Charmin sponsored a set of public restrooms at 1540 Broadway in Times Square during 2006 and 2007; these toilets were used more than 500,000 times in 2006 alone.
Construction costs
The cost to build public toilets varies widely. A bathroom in Ferry Point Park in the Bronx cost $4.7 million in 2018 and, at the time, was the most expensive public restroom ever built in New York City. Another bathroom on Aqueduct Walk, also in the Bronx, cost approximately $1 million. On average, in 2019, a public toilet cost $3.6 million to construct. By contrast, in 2011, the Parks Department was spending an average of $1.3 million per project. According to a 2022 report by local television station NY1, existing restrooms cost between $1.4 million and $2.2 million to renovate, while new restrooms cost $3.5 million on average. , a restroom under construction in Seaside Wildlife Nature Park in Staten Island is estimated to cost $6.8 million at completion.
The construction costs of public toilets in New York City have sometimes been the subject of controversy. When a $2.3 million public toilet opened at Elmhurst Park in Queens in 2012, community leader Robert Holden stated: "It's just a tremendous waste of space and, especially, money." Another bathroom at Gravesend Park in Brooklyn, which was completed in 2017 for $2 million, also elicited complaints. Following a controversy over the cost of the Ferry Point Park bathroom, in 2019, the New York City government proposed constructing movable trailers with portable toilets to save money.
Pay toilet programs
Earlier attempts
Under the administration of mayor David Dinkins, French company JCDecaux placed several pay toilets across New York City in 1992. As part of the program, JCDecaux was to operate one toilet for handicapped users and four toilets for able-bodied users for four months. If the pilot program was successful, 95 more toilets would be installed across the city. After a successful pilot of the toilets, in early 1993, the New York City Council mandated that JCDecaux provide a single design for handicapped and able-bodied users. JCDecaux objected to the condition, saying that it wished to construct special toilets for handicapped users that required magnetic cards for access. The City Council withdrew its demand for a single restroom design. JCDecaux quit the project anyway in October 1993 because of disputes over the number of ads that would be placed on the restrooms.
In 1994, the New York City Department of Parks and Recreation and the New York City Department of Transportation separately began testing wheelchair-accessible toilets. The New York City Council had planned to award a contract for the toilets the same year, but this contract was delayed because of disputes over the sizes of advertisements on the proposed restrooms. By late 1994, the city had only one automated pay toilet in front of New York City Hall; this toilet was removed in 1997. The New York City government again planned to award a contract for 30 pay toilets in 1996, as part of a larger plan that also included redesigning the city's newsstands and bus stops. If the program had been implemented, the toilets would have been installed starting in 1998. However, mayor Rudy Giuliani halted the program in 1998 following major controversies. Among the complaints was the cost of each toilet, the number of accessible toilets, the presence of advertising on the restrooms, and opposition to the toilets in many neighborhoods.
In January 2001, the city opened automated self-cleaning pay toilets at Herald and Greeley Squares. The toilets worked about 90 percent of the time. The toilets were managed by a local business improvement district, 34th Street Partnership. According to the partnership, the toilets were unsatisfactory for a variety of reasons including the 2-minute clean time between users, cost of maintenance, and declining of popularity. By 2008, the automated self-cleaning pay toilets at Herald and Greeley Squares were shut down and replaced with manually cleaned ones.
Cemusa agreement
When Michael Bloomberg became mayor of New York City in 2002, he announced plans to install pay toilets in the city. Many newsstand owners opposed the project as it allowed the private company managing the toilets to manage their newsstands as well. In 2005, as part of a $1 billion, 20-year agreement with Spanish company Cemusa, the firm planned to place 20 public toilets around New York City. Prototypes of the toilets were announced in early 2006; these toilets cost 25 cents to use for 15 minutes. The first toilet was installed in Madison Square Park in March 2008 and was extremely popular. Despite the city's plan to install five toilets by the end of 2008, only one other toilet had been installed by mid-2009, in Corona, Queens. By the mid-2010s, only three toilets had been installed. Two additional toilets were installed by 2018, over halfway through the agreement with Cemusa (which had since merged with JCDecaux), while the other fifteen toilets were in storage. The program faced several obstacles, including community opposition in several neighborhoods, as well as the city's refusal to install pay toilets in flood-prone neighborhoods. The 5 public toilets accommodated between 15 and 50 visitors a day on average.
the New York City 311 website described the toilets as "climate-controlled and include a toilet, a wash basin with running warm water, and a mirror". They are open from 8am to 8pm, cost $0.25 to use, and are ADA compliant. The site also accepts complaints about existing facilities and requests for new ones.
Expansion of free toilets
All subway restrooms were closed in 2020 due to the COVID-19 pandemic and remained shuttered for over two years. The MTA reopened eighteen restrooms at nine subway stations in January 2023, with plans to reopen restrooms at an additional twelve stations that May. , there were 58 open bathrooms throughout the subway system.
The city's lack of public restrooms was especially noticeable during the COVID-19 pandemic, when many restrooms were closed. In early 2022, city councilmember Rita Joseph introduced a bill that would mandate the construction of public restrooms in every neighborhood in New York City. On October 27, 2022, the New York City Council passed local law 2022/114. The bill directs a report to be prepared which identifies the currently available public bathrooms, and feasible locations for new ones in most Zip Code Tabulation Areas in the city. In 2023, the City Council introduced legislation that would require one public toilet per 2,000 residents, thereby increasing the number of public toilets in the city to 4,000 by 2035. The city government announced in June 2024 that, as part of the "Ur In Luck" program, it would construct 46 restrooms and renovate another 36 restrooms citywide.
See also
New York City water supply system
America (Cattelan) – functioning gold toilet sculpture created in 2016 for the Solomon R. Guggenheim Museum by Italian artist Maurizio Cattelan
References
External links
Toilets
Infrastructure in New York City
Restrooms in the United States | Toilets in New York City | [
"Biology"
] | 2,590 | [
"Excretion",
"Toilets"
] |
72,483,634 | https://en.wikipedia.org/wiki/Trichoglossum%20walteri | Trichoglossum walteri is a species of fungus in the family Geoglossaceae. In its current sense, it is considered to be cosmopolitan and as such represents a complex of species worldwide. In the UK, it has been given the recommended English name of short-spored earthtongue. The European species occurs mainly in agriculturally unimproved grassland and threats to this habitat have resulted in the short-spored earthtongue being assessed as globally "vulnerable" on the IUCN Red List of Threatened Species.
Taxonomy
The species was first described by English mycologist Miles Joseph Berkeley in 1875 as Geoglossum walteri. His description was based on an Australian collection and in its strict sense Trichoglossum walteri may be restricted to the southern hemisphere. The name was, however, adopted for collections with similar microscopic features in North and South America, Europe, and Asia. It seems probable that some of these collections represent distinct species. Initial molecular research, based on cladistic analysis of DNA sequences, supports this conclusion and also indicates that Trichoglossum walteri sensu lato is not closely related to the type species of Trichoglossum, but belongs in a separate genus as yet not formally named.
Description
Ascocarps are club-shaped, up to 35 mm (1.5 in) tall, black to dark brown, with a swollen, spore-bearing head, up to half the ascocarp height, and a finely hirsute, cylindrical stipe (stem). Microscopically, dark, thick-walled, acute setae are present. The asci are 8-spored, the ascospores 90–100 × 4.5–5.5 μm, becoming 7-septate at maturity. North temperate collections differ in being larger, up to 100 mm (4 in) tall, and in having shorter ascospores, 75–85 × 4.5–5.5 μm.
Similar species
All Trichoglossum species appear similar in the field and can only be identified by microscopic examination. In European grassland, the short-spored earthtongue is most easily confused with the much commoner Trichoglossum hirsutum which has longer spores that become 15-septate at maturity.
Conservation
In Europe the short-spored earthtongue is typical of waxcap grasslands, a declining habitat due to changing agricultural practices. As a result, the species is of global conservation concern and is listed as "vulnerable" on the IUCN Red List of Threatened Species.
References
Geoglossaceae
Fungi of North America
Fungi described in 1875
Fungi of Australia
Fungi of Europe
Taxa named by Miles Joseph Berkeley
Fungus species | Trichoglossum walteri | [
"Biology"
] | 555 | [
"Fungi",
"Fungus species"
] |
72,484,054 | https://en.wikipedia.org/wiki/HD%2059640 | HD 59640 is a solitary white hued star located in the southern circumpolar constellation Volans. It has an apparent magnitude of 6.48, placing it near the limit for naked eye visibility. Gaia DR3 parallax measurements place the object at a distance of 262 light years and it is receding with a heliocentric radial velocity of . At its current distance, HD 59640's brightness is diminished by three tenths of a magnitude due to interstellar dust.
This is an ordinary A-type main-sequence star with a stellar classification of A3 V. It has 1.82 times the mass of the Sun and 1.77 times its radius. It radiates 13.7 times the luminosity of the Sun from its photosphere at an effective temperature of . HD 59640 has an iron abundance 63% that of the Sun, making it metal deficient. In 2020, Maximillian N. Günther and colleagues found the object to be an eruptive variable star with flares lasting up to 10 minutes. However, they are rather small, with the maximum being only two hundredths of a magnitude.
References
A-type main-sequence stars
Eruptive variables
Suspected variables
Volans
Volantis, 11
CD-71 00402
059640
035946 | HD 59640 | [
"Astronomy"
] | 274 | [
"Volans",
"Constellations"
] |
75,251,847 | https://en.wikipedia.org/wiki/HD%207977 | HD 7977 (also designated as TYC 4034-1077-1 or USNO-A2 1500-01356484) is a G-type main-sequence star located in the constellation of Cassiopeia, around 246.9 light-years away from Earth. HD 7977 is notable for its close flyby of the Solar System 2.8 million years ago. Its flyby may have taken it close enough to the Sun that it penetrated deep into the Oort Cloud and disturbed the population of Oort Cloud bodies and long-period comets there. Its mass is equivalent to 1.07 times the Sun's mass.
References
Cassiopeia (constellation)
7977 | HD 7977 | [
"Astronomy"
] | 147 | [
"Cassiopeia (constellation)",
"Constellations"
] |
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